description stringlengths 2.98k 3.35M | abstract stringlengths 94 10.6k | cpc int64 0 8 |
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TECHNICAL FIELD
The present invention generally relates to a net, and more specifically to an expandable knitted net comprising a plurality of fill yarns with elastomeric properties that allows the net to expand in the cross-direction, or a plurality of chain yarns with dissimilar elongation performance.
BACKGROUND OF THE INVENTION
Netting is often prepared either by knitting, weaving, or extrusion. Knitted netting typically comprises a plurality of threads oriented in a first direction and being essentially equal spaced from one another, and having wefts oriented in a second direction which is perpendicular to the first direction, the threads and wefts being interlocked and secured. Nets may be prepared by a Raschel knitting method, a process in which the threads are attached to knitting elements that comprise two needles and knock-over comb bars positioned opposite to one another, and comprising ground guide bars, pattern guide bars and stitch comb bars. An example of such a knitted net is described in European Patent No. 0 723 606, to Fryszer, et al., incorporated herein by reference.
Knitted netting has a variety of end use applications, including but not limited to hay bale wrap, cargo wrap, netted bags, and drainage nets. Raschel knitted nets have been used for round hay bale wrapping as disclosed in U.S. Pat. No. 4,569,439 and U.S. Pat. No. 4,570,789, both hereby incorporated by reference. Twines and films have also been used to tie up hay bales; however the twine usually cuts in the bale and doesn't provide ample support to keep the bale tidy and neat. Further, the twining of the rolled bales with the binding yarn is relatively time-consuming and requires substantial manual labor. Film covers don't allow the rolled bale enough air circulation, which lead to the growth of mold and eventually rotting. The Raschel knitted net doesn't cut into the hay bale and allows ample amount of air to circulate through the bale. Although Raschel knitted netting has several advantages over twine and plastic film, the netting tends to shrink in overall width when pulled lengthwise. Due to the shrinkage in the width, the outer most edges of the hay bale are left exposed, which can cause the bale to become disheveled during pick-up and transport.
There is an unmet need for a net that will provide maximum coverage to a rounded bale maintaining the rolled bale compact shape during pick-up and transport, as well as during storage.
SUMMARY OF THE INVENTION
The present invention is directed to a knitted net, and more specifically to an expandable knitted net. In one form, the net comprises a plurality of fill yarns with an elastomeric performance, which allows the net to expand in the cross-direction. In another form, the present invention is directed to a netting, and more specifically to a knitted netting comprising a plurality of chain yarns with dissimilar elongation performance oriented in a first direction, and a plurality of fill yarns oriented in a second direction, wherein the yarns oriented in the second direction secure the yarns oriented in the first direction in position within the netting.
In accordance with the present invention, the netting is used as bale wrap. In one form, the bale wrap comprises a plurality of chain yarns orientated in a first direction and a plurality of fill yarns orientated in a second direction. The elastomeric performance of the fill yarns provide for optimal coverage of the bale upon stretching of the netting. When stretched in the cross-direction, the netting easily conforms about the shape of a rolled bale, hugging the surface so as to maintain the compact nature of the rolled bale. In another form of the present invention, the netting is used as bale wrap. The bale wrap comprises a plurality of chain yarns oriented in a first direction, wherein the yarns have dissimilar elongation performances. The dissimilar elongation performances of the yarns provide for optimal coverage of the bale upon stretching of the netting. In order to achieve the desired necking performance when stretching the netting, the yarns located proximal to either edge have a higher elongation performance than those located distal to the outer edges Upon stretching, those yarns located proximal the outer edges stretch further than those located distal to the outer edges. This causes the outer edge of the net to flair, allowing the net to fold over the edges of the hay bale, maintaining the compact nature of the rolled bale.
The yarns of the present invention may comprise flat filaments, such as tapes, mono-filaments, or a combination thereof. The filaments may be of similar or dissimilar polymeric compositions. Suitable filaments, which may be blended in whole or part with natural or synthetic polymeric compositions, include polyamides, polyesters, polyolefins, polyvinyls, polyacrylics, and the blends or coextrusion products thereof. The synthetic polymers may be further selected from homopolymers; copolymers, conjugates and other derivatives including those thermoplastic polymers having incorporated melt additives or surface-active agents.
It is within the purview of the present invention that the fill yarns comprise a varying degree of elasticity. For instance, it has been contemplated that the fills yarns located proximal to the outer edges comprise greater elasticity than those fill yarns located distal to the outer edges of the net. The dissimilarities in the elasticity performance of the fill yarns can establish specific zones within the netting. A zone is defined as an area within the netting that is comprised of more than one chain yarn and more than one fill yarn, whereby the fill yarns have a similar elasticity performance. The netting may be comprised of two or more zones. Further, the yarns of one zone may comprise similar or dissimilar yarns than that of a second zone. Further still, the yarns of one zone may comprise similar or dissimilar topical or internal additives than that of a second zone.
The yarns of the present invention may comprise flat filaments, such as tapes, mono-filaments, or a combination thereof. The filaments may be of similar or dissimilar polymeric compositions. Suitable filaments, which may be blended in whole or part with natural or synthetic polymeric compositions, include polyamides, polyesters, polyolefins, polyvinyls, polyacrylics, and the blends or coextrusion products thereof. The synthetic polymers may be further selected from homopolymers; copolymers, conjugates and other derivatives including those thermoplastic polymers having incorporated melt additives or surface-active agents.
It is within the purview of the present invention that the chain yarns of dissimilar elongation orientated in the first direction, establish specific zones within the netting. A zone is defined as an area within the netting that is comprised of more than one chain yarn having similar elongation performance. The netting is comprised of at least three zones, wherein the zones located proximal to the outer edges comprise a greater elongation performance than the zones located distal to the outer edges. Further, the chain yarns of one zone may comprise similar or dissimilar chain yarns than those of a second zone. Further still, the chain yarns of one zone may comprise similar or dissimilar topical or internal additives than those of a second zone.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates a view of a portion of a Raschel machine;
FIG. 2 is a representation of the zones within the net of the present invention while the net is in a relaxed state, which zones can be provided in differentially elongated netting;
FIG. 3 is a representation of the zones within the net of the present invention while the net is in a stretched state;
FIG. 4 is a diagrammatic view of the netting partially wrapped about a rounded bale; and
FIG. 5 is a diagrammatic view of differentially elongated netting.
DETAILED DESCRIPTION
While the present invention is susceptible of embodiment in various forms, there will hereinafter be described, presently preferred embodiments, with the understanding that the present disclosure is to be considered as an exemplification of the invention, and is not intended to limit the invention to the specific embodiments disclosed herein.
In accordance with the present invention, the expandable knit is formed on a Raschel knitting machine. The machine comprises a plurality of latch needles, a plurality of lapping belts, a yarn laying-in comb and a plurality of guide bars having needle guides thereon. The latch needles are mounted in the machine to carry out a reciprocating motion in a given plane while the lapping belts are spaced from the needles on one side of the plane, i.e., on a downstream side, for guiding pattern yarns to the needles. In addition, the laying-in comb is mounted on the same side of the plane of the latch needles as the lapping belts and carries out an orbital motion perpendicularly of the plane of the latch needles to penetrate between the pattern yarns. The guide bars with the needle guides serve to lay-in stitch yarns and are mounted on an opposite side of the plane of the latch needles from the lapping belts, i.e. on the upstream side, and oscillate at an angle to the pattern yarns.
FIG. 1 , is representative of a Raschel machine, whereby it is provided with a comb plate 1 in which a plurality of latch needles 3 are mounted for reciprocating motion along their axes 2 in a vertical plane, as viewed. As shown, the needles 3 are disposed on a bar 4 which is movable up and down.
In addition, the machine includes a plurality of lapping belts or guide bars 5 spaced from the needles 3 on one side, i.e. the downstream side, of the plane of the needles 3 for guiding pattern yarns to the needles 3 . A yarn laying-in comb 6 is also mounted on the same side of the plane 2 of the latch needles 3 in order to carry out an orbital motion perpendicularly of the plane 2 while penetrating between the pattern yarns. As indicated in chain-dotted line 7 , the orbital motion is a combined stroke and oscillating motion. The comb 6 is provided with a plurality of parallel sinkers 8 each of which carries a guide rod 9 and which has a deflecting edge 10 at the forward end extending towards the plane 2 . In addition, each sinker 8 has a yarn catch 11 at a lower region of the deflecting edge 10 below the guide rod 9 . A trace comb 12 is also mounted over the comb plate 1 in known manner.
The machine also has a plurality of guide bars 13 which have needle guides thereon for directing stitch yarns to the latch needles 3 . As shown, the guide bars 13 are mounted on the side of the plane 2 of the latch needles 3 opposite the lapping belts 5 , i.e., on the upstream side. Suitable means are also provided for oscillating the guide bars 13 at an angle to the pattern yarns.
As shown in FIG. 1 , the lapping belts 5 are positioned at an acute angle downstream of the plane 2 . A yarn guide 14 is also disposed between the belts 5 and the guide bars 13 for deflecting the pattern yarns upon laying-in of the stitch yarns. This yarn guide 14 is used for laying the pattern yarns in the needle lanes (not shown). The yarn guide 14 may be coupled to the guide bars 13 so as to move therewith or may be provided with an independent drive (not shown).
The netting of the present invention is knitted on such a machine, wherein in one form a plurality of chain yarns are orientated in a first direction and a plurality of elastomeric fill yarns are orientated in a second direction. Elastomeric fill yarns may be utilized in entirety or in part throughout the net. Further, the elastic fill yarns may be of varying degrees of elasticity. It is also in the purview that the net comprise zones, wherein a zone is characterized by its degree of elasticity or complete lack thereof. The chain yarns are interconnected with fill yarns orientated in a second direction on a Raschel machine forming a net, wherein the net exhibits the ability to expand in the cross-direction.
In another form of the invention, the netting of the present invention is knitted on such a machine, wherein at least three chain yarns of a first elongation performance are orientated in a first direction and at least two chain yarns of a second elongation performance orientated in said first direction. The chain yarns of a first elongation performance are arranged into two zones, wherein each zone is located proximal to an outer edge. Chain yarns of a said second elongation performance are arranged into a separate zone and the zone is located distal to the outer edges or intermediate the two proximal zones. The chain yarns are interconnected with fill yarns orientated in a second direction on a Raschel machine forming a net, wherein the net exhibits differential elongation.
Referring to FIG. 2 therein is a diagrammatic representation of the knitted net of the present invention in a relaxed state. In one form, the net of FIG. 2 comprises three zones, wherein zone one (Z 1 ) has a greater elasticity performance than zone two (Z 2 ) and zone three (Z 3 ) has a greater elasticity performance than zone two (Z 2 ). Upon stretching, the net exhibits differential expansion in the cross-direction. It's in the purview of the present invention that the yarns of one zone may comprise similar or dissimilar yarns than that of a second zone. Further still, the yarns of one zone may comprise similar or dissimilar topical or internal additives than yarns of a second zone.
In another form, the net comprises at least three zones, wherein zone one (Z 1 ) has a greater elongation performance than zone two (Z 2 ) and zone three (Z 3 ) has a greater elongation performance than zone two (Z 2 ). Preferably, the zones located most proximal to the outer edges have an elongation performance at least 110% greater, more preferably 120% greater, and most preferably 130% greater than the zone(s) located distal to the outer edges.
FIG. 3 shows the netting once it is stretched. Due to the elasticity of the fill yarns, the net is able to expand in the cross-direction, easily conforming to the shape of a rolled bale and folding over the edges of the bale so as to prevent the bale from becoming disheveled along the ends. FIG. 4 demonstrates how the expandable net fits around the bale to keep it compact and neat.
It is within the purview of the present invention that the chain yarns of one zone may comprise similar or dissimilar chain yarns than those of a second zone. Further still, the chain yarns of one zone may comprise similar or dissimilar topical or internal additives than those of a second zone. It's also in the purview of the present invention that the fill yarns of one zone may comprise similar or dissimilar fill yarns than that of a second zone. Further still, the fill yarns of one zone may comprise similar or dissimilar topical or internal additives than fill yarns of a second zone.
FIG. 3 shows the necking that occurs once the netting is stretched. Due to the increase in elongation of the yarns located along the outer edges, the final net construct is capable of wrapping over the edges of the bale so as to prevent the bale from becoming disheveled along the ends. FIG. 4 demonstrates how the differentially elongated net fits around the bale to keep it compact and neat.
Subsequent to formation, the knitted net material may optionally be subjected to various chemical and/or mechanical post-treatments. The net material is then collected and packaged in a continuous form, such as in a roll form, or alternatively, the net material may comprise a series of weak points whereby desired lengths of twine material may be detracted from the remainder of the continuous packaged form.
From the foregoing, it will be observed that numerous modifications and variations can be affected without departing from the true spirit and scope of the novel concept of the present invention. It is to be understood that no limitation with respect to the specific embodiments illustrated herein is intended or should be inferred. The disclosure is intended to cover, by the appended claims, all such modifications as fall within the scope of the claims. | The present invention is directed to a knitted net, and more specifically to an expandable knitted net. In one form, the net comprises a plurality of fill yarns with an elastomeric performance, which allows the net to expand in the cross-direction. In another form, the present invention is directed to a netting, and more specifically to a knitted netting comprising a plurality of chain yarns with dissimilar elongation performance oriented in a first direction, and a plurality of fill yarns oriented in a second direction, wherein the yarns oriented in the second direction secure the yarns oriented in the first direction in position within the netting. | 3 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates generally to beam-forming illumination systems, and more specifically to those with sufficiently narrow solid angles for the output beam to be called collimators. Examples are flashlights and searchlights. The primary limitation upon their performance is étendue-invariance, by which the angular radius θ of the beam is determined by the ratio of source diameter d to aperture diameter D: sin θ=d/D, when the source radiates into a hemisphere. The beamwidth is twice the angular radius and usually is defined as full width at half maximum (FWHM).
[0002] Light emitting diodes (LEDs) are an example of such a hemispheric source. Their small size and ever-improving luminous efficacy are propelling them into market predominance in many fields of lighting. Since their hemispheric emission is too wide for most lighting tasks, LEDs are installed in luminaires that generate narrower output angles. So far, LED flashlights are gaining market prominence, and LED downlights are being installed in ceiling receptacles. Automotive headlights in particular are and example of a field where market pressure for device compactness collides with the étendue theorem. The present luminaires can augment LED brightness, and some embodiments can achieve aperture widths only half the étendue-limited size, with only a modest sacrifice in overall output flux.
SUMMARY OF THE INVENTION
[0003] The present luminaires relate generally to collimating illumination optics, and more particularly, but not exclusively, to the small minority of optics with a beamwidth that is largely uniform across the aperture. Different parts of the output beam are generated by light emitted at different off-axis angles by the source. Collimators that suffer from comatic aberration, such as the parabola and the Fresnel lens, have a beamwidth that is wider at the center of the output aperture than at the edge. In contrast, there are several collimators with constant beamwidth across the aperture, including the compound parabolic concentrator (CPC). Three more such constant-beamwidth collimators are the subjects of the following US Patents, which have the same assignee as the present invention and are herein incorporated by reference:
1. U.S. Pat. No. 6,639,733 to Miñano et al. 2. U.S. Pat. No. 6,896,381 to Benitez et al., including the subsequent augmentations in U.S. Pat. No. 7,152,985 & U.S. Pat. No. 7,181,378) 3. U.S. Pat. No. 7,006,306 to Falicoff et al.
[0007] The present luminaires exploit the reflectivity of light emitting diodes (or other light sources) relative to external illumination. In particular, an LED will diffusely reflect illumination from the retroreflection of its own emission. In each of the listed collimators, light going towards the outside of the aperture is specularly retroreflected back to the LED. The reflectivity of a phosphor-conversion white LED at longer wavelengths can be as much as 90%. The reflectivity of a blue LED reflecting blue light may typically be around 70%. The reflection of retroreflected radiation at the source, and the consequent radiance increase, are not in contradiction with Kirchhoff's law of thermal radiation for several reasons, among which are the non-equilibrium and the non black body nature of the whole LED.
[0008] This LED diffuse-reflectivity acts to recycle the retroreflected light, so that some of the light then goes out through the restricted exit aperture and the rest is retroreflected yet again. Each cycle of retroflection adds to the LED's original luminance, albeit with decreasing returns.
[0009] LED recycling in the prior art utilizes the diffuse reflectivity of nearby surfaces, as in a white-walled cavity, with not much role for the LED's own reflectivity. The present luminaires, however, use retroreflectors, which use specular reflection or operate via total internal reflection (TIR), to return light only to the LED or other light source. In many configurations, the LED or other light source reflects this returned light in a diffusely scattering manner so that some of it scatters into the restricted aperture. The use of specular recycling in the prior art involved large specular mirrors which shined light through the source, particularly the windings of a coiled incandescent filament or the transparent gas of an arc lamp. In contrast, the much smaller size and hemispheric operation of LEDs calls for the novel configuration disclosed herein.
[0010] When a constant-beamwidth collimator is cut to half its original aperture diameter, only about ¼ of the LED's flux will be directly transmitted. Call this the transmission fraction f T , so that the amount retroreflected is 1−f T . Of course, a real collimator is not 100% efficient to start with, having instead a transmittance T, usually 85% for the listed collimators, of a ray's original energy surviving to emerge through the exit aperture. A metallic coating for the retroreflector will typically have a reflectivity of at most 88%, at least in standard commercially available second-surface mirror coatings. Call this ρ r . It is possible that more expensive multi-layer mirror coatings can be as much as 98% efficient, and their extra cost may be worth it.
[0011] Beyond the efficiency of retroreflection, various optical errors will cause some of this light to miss the LED, generating an intercept efficiency ρ I , typically of up to about 90%. In some of the preferred embodiments disclosed herein, this value is nearly 100%. An LED's diffuse reflectivity, ρ L =85% for a white LED, overlays this return light on the LED's original emission, enhancing the apparent brightness of the LED.
[0012] For each lumen produced by the LED, the fraction Tf T is emitted by the aperture in a first pass. The fraction (1−f T )ρ r ρ I is returned to the LED, whence it is reflected so that the fraction F R =(1−f T )ρ r ρ I ρ L =50.5% joins the original emission. The infinite-series summation of this recycling, in accordance with the well-known identity,
[0000]
a
∑
n
=
0
∞
r
n
=
a
1
-
r
,
[0000] results in a total emission out the aperture of F e =Tf T /(1−F R )=40%. This is a considerable sacrifice to pay for cutting the aperture diameter in half, suggesting a less ambitious reduction. For example, a 29% reduction in aperture diameter (50% area) results in f T =50% and F e =64%, a less onerous outcome.
[0013] In a more favorable case, ρ r =98% and ρ I =98%, we have F R =61% for an aperture that is 25% the original area (50% of the original diameter), giving F e =54%, and for a 50% area aperture, F R =41% and F e =71%. These improved efficiencies could justify the extra expense of the superior retroreflective efficiency.
[0014] Although each recycling piles a 9% addition on the LED's heat load, or 9%/(1−F R )=18% in all, the LED's heat load to start with is about 2.5 times its light emission, so this extra heat is not a concern. The primary concern, of course, is the cost expressed by F e . Recent trends in LED efficacy, however, have pushed from last year's 40-60 lumens per Watt (LPW) to current 100 LPW, with LED manufacturers predicting that outputs of 140 LPW will be available by the year 2009. Thus an automotive LED headlamp with half the étendue-invariant area would in spite of a one-third loss draw much less current than the larger incandescent lamp it outshines.
[0015] Many of the present luminaires can be categorized into two main types of collimator apparatus. The first type of collimator increases the source's effective luminance (and the étendue of the exit aperture of the device) but the overall size of the optic or diameter of the optical system, including the retroreflecting features, is approximately the same as a standard collimator with the same source. The second type of collimator increases the effective luminance of the source but also decreases the diameter of the optical system compared to the “standard” optic. In this case the diameter of the new optic will be smaller than the standard optic that achieves the same degree of collimation with the same source. Both these apparatus escape the classical étendue constraints, but the second type has the advantage over the first that the diameter of the overall system (not just the optical exit aperture) is reduced. Therefore the second type of apparatus should be useful for such applications as automotive forward or rear lighting, where frontal real estate on the vehicle is scarce but luminous performance cannot be compromised. Virtually all of the embodiments disclosed herein are of the second type, but the principles taught also can be applied to those of the first type.
[0016] The two types of collimator apparatus can be further divided into two sub-categories. There is the case where the retroreflection features are close to (or proximal) the source and the collimation feature is remote from the source. One example of this type of apparatus is shown in FIG. 9 , where lens 22 is farther away from the source than the retroreflectors 23 . In the second sub-category the retroreflectors are not proximate to the source and can be further away than the nearest points on the exit surface of the optic. An example of this type of collimator is illustrated in FIG. 21 .
[0017] In one embodiment, there is provided a collimating luminaire comprising a light-source with a diffuse reflectivity exceeding one half. A collimator intercepts the emitted light of the source. The collimator produces a beamwidth across its exit aperture that is preferably substantially uniform, and a system of retroreflectors returns part of the emitted light to the source. The retroreflectors allow the removal of an outer part of the exit aperture, so that the remaining exit aperture is smaller than the étendue-limited aperture for the beamwidth in question.
[0018] In another embodiment, there is provided a collimating luminaire comprising a light-source with a diffuse reflectivity exceeding one half, the luminaire defining an exit aperture and intercepting the emitted light of the source in directions outside the exit aperture. The luminaire comprises at least one at least approximately elliptically concave retroreflector that returns part of the emitted light to the source.
[0019] In a further embodiment, there is provided a collimating luminaire comprising a light-source with a diffuse reflectivity exceeding one half, and a collimator intercepting the emitted light of the source. The luminaire produces a substantially uniform beamwidth across its exit aperture, and a system of forward reflectors directs part of the emitted light to the exit aperture. The system of reflectors allowing the removal of the outer part of the exit aperture, so that the exit aperture is smaller than the étendue-limited aperture for the beamwidth.
[0020] In another embodiment, there is provided a combined collimator and retroreflector that can be combined with a suitable light source to form a luminaire embodying the invention.
[0021] At least one focus of an ellipse defining the elliptically concave retroreflector may be at least approximately at an edge of a beam of light that reaches the retroreflector from the source. At least one focus of the ellipse may then be at least approximately at an edge of the light source.
[0022] At least one focus of the ellipse may be at least approximately at an edge of an opaque object that cuts off the beam of light. If the luminaire comprises at least two said retroreflectors, at least one focus of the ellipse defining a first retroreflector may be at least approximately at an edge of a second retroreflector between the source and the first retroreflector.
[0023] The luminaire may comprise at least one forward reflector positioned to direct intercepted light through the exit aperture in such a manner as to produce a substantially uniform beamwidth across the exit aperture wherein the exit aperture is smaller than the étendue-limited aperture for the beamwidth.
[0024] At least one forward reflector may be at least approximately hyperbolically concave. At least one focus of a hyperbola defining the hyperbolically concave forward reflector may then be at least approximately at an edge of a beam of light that reaches the forward reflector from the source. At least one focus of the hyperbola may be at least approximately at an edge of the light source. At least one focus of the hyperbola may be at least approximately at an edge of at an edge of an opaque object that cuts off the beam of light, and the opaque object may then be an edge of a said retroreflector between the source and the forward reflector. The retroreflectors may operate in air. The retroreflectors may operate inside a dielectric.
[0025] The retroreflectors may reflect by micro-linear grooves. The retroreflectors may reflect by a thin film stack. The thin film stack may have an initial layer of a low index of refraction material with a thickness approximately equal to two times the nominal wavelength for stack.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] The above and other aspects, features, and advantages of the present invention will be more apparent from the following more particular description thereof, presented in conjunction with the following drawings wherein:
[0027] FIG. 1 shows for a flat Lambertian light source the hyperbolic flowlines and the elliptical “ortho-flowlines,” which are curves everywhere orthogonal to the flowlines.
[0028] FIG. 2 shows reflectors that do not alter the flowlines.
[0029] FIG. 3 shows an alternative deployment of elliptical reflectors.
[0030] FIG. 4 shows yet another alternative deployment of elliptical reflectors.
[0031] FIG. 5 shows a circular area A 1 with radius R and another circular area A 2 with radius r, a distance d apart.
[0032] FIG. 6 shows a graph of the theoretical increase in brightness for an exemplary elliptical reflector of the embodiment of FIG. 1 as a function of LED reflectivity.
[0033] FIG. 7 is a cross-sectional view of the exemplary elliptical reflector used to generate the graph of FIG. 6 .
[0034] FIG. 8 is a plan view of the position of the foci for elliptical reflector of FIG. 7 .
[0035] FIG. 9 shows a collimating lens above an array of elliptical mirrors.
[0036] FIG. 10 shows a collimating lens with a mirror-coated, externally grooved cylindrical retroreflector.
[0037] FIG. 11 shows a Fresnel lens with the retroreflector, including close-ups of reflected rays.
[0038] FIG. 12 shows a CPC with flowlines and ortho-flowlines.
[0039] FIG. 13 shows how the CPC's aperture is restricted, with étendue-limited beamwidth unchanged.
[0040] FIG. 14 shows how the CPC's width is reduced.
[0041] FIG. 15 shows a dielectric total internally reflecting concentrator (DTIRC).
[0042] FIG. 16 shows a family of flowlines and ortho-flowlines in a DTIRC showing the boundary lines for a three-tier retroreflector drawn to scale.
[0043] FIG. 17 shows a DTIRC with flowline retroreflectors having four tiers.
[0044] FIG. 18 is a perspective view of a DTIRC with three-tiers of retro-reflectors drawn to scale.
[0045] FIG. 19 shows a further embodiment with flowline retroreflectors having five tiers.
[0046] FIG. 20 shows an embodiment similar to one shown in the above-referenced U.S. Pat. No. 6,896,381 to Benitez et al.
[0047] FIG. 21 shows a device similar to that of FIG. 20 truncated by retroreflectors.
[0048] FIG. 22 shows an embodiment similar to one shown in the above-referenced U.S. Pat. No. 7,006,306 to Falicoff et al.
[0049] FIG. 23 shows the device of FIG. 22 truncated by retroreflectors.
[0050] FIG. 24 shows a further embodiment similar to one shown in the Falicoff '306 patent.
[0051] FIG. 25 shows the device of FIG. 24 truncated by V-groove retroreflectors.
[0052] FIG. 26 shows a device similar to that of FIG. 11 , but with a mushroom lens to reduce beamwidth.
[0053] FIG. 27 shows an elliptical reflector made of a micro linear retroreflector material whose grooves are curves normal to the flowlines.
[0054] FIG. 28 shows a cross section of an elliptical retroreflector with micro linear retroreflector normal to the flowlines.
[0055] FIG. 29 shows the reflectance as a function of wavelength of a second surface thin film reflector at 0° incidence angle.
[0056] FIG. 30 shows a family of flowlines and ortho-flowlines in a further embodiment of a luminaire, showing the boundary lines for a two-tier retroreflector drawn to scale.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0057] A better understanding of various features and advantages of the present luminaires will be obtained by reference to the following detailed description of the invention and accompanying drawings, which set forth illustrative embodiments. Corresponding reference characters indicate corresponding components throughout the several views of the drawings.
[0058] Flowlines are well known in the field of non-imaging optics, being defined at any point receiving light from a source. At some viewing point, rays are received from across the source, and the rays from the source's edges define the edge of the source image. In the case of the following Figures, the flowlines are everywhere tangent to the bisectors of the angle formed by the rays from the two edges of the source.
[0059] FIG. 1 is a two-dimensional view across a light source 1 , emitting upwards between point A and point B. Flowlines 2 are confocal hyperbolas with those points A and B as their foci. At every point upon the flowlines 2 , the local tangent is the bisector of the lines to points A and B. The lines 3 , referred to herein as “ortho-flowlines,” are defined as the family of lines that are everywhere orthogonal to the flowlines 2 . In FIG. 1 , the ortho-flowlines 3 are confocal ellipses. In general, the shape of the ortho-flowlines is determined by the shape and distribution of the flowlines. In particular, elliptical segments 4 of one of the confocal ellipses 3 form a light barrier extending from the plane of light source 1 , with a dotted line 5 denoting a central aperture between the barrier segments 4 .
[0060] FIG. 2 shows the source 1 extending between points A and B, with elliptical specular reflectors 6 and 8 lying on two of the confocal ellipses of FIG. 1 and joined by hyperbolic specular reflectors 7 lying on hyperbolic flowlines of FIG. 1 . Because they lie on the flowlines, the reflectors 6 , 7 , 8 do not alter the fundamental character of the light field of source 1 , but merely return some of the radiation from source 1 back to source 1 . When source 1 is reflective, and especially when source 1 is diffusely reflective, some of the returned light will be radiated upwards, missing reflectors 6 , 7 , 8 and adding to the luminance of source 1 emerging through aperture 5 . Light emitting diodes have a diffuse reflectivity, making possible the present luminaires.
[0061] FIG. 3 shows horizontal source 1 extending between points A and B, and exemplary vertical dotted line 9 proceeding upward from point. B. Elliptical arc reflector 10 has its foci on points A and B, and terminates at its inner end upon line 9 at point C. Above reflector 10 is disposed elliptical arc reflector 11 with foci on points A and C, and terminating at its inner end upon line 9 at point D. Above reflector 11 is disposed elliptical arc reflector 12 , which has foci on points A and D and terminates on line 9 at point E. This system of reflectors is less sensitive to fabrication errors than that of FIG. 2 .
[0062] FIG. 4 also shows source 1 extending between points A and B, and reflectors 13 , 14 , and 15 with terminating points and foci F, G, & H analogous to points C, D, & E in FIG. 3 . However, points F, G, & H are not collinear, unlike points C, D, & E in FIG. 3 .
[0063] FIG. 5 shows a circular area A 1 with radius R and another circular area A 2 with radius r. Circular areas A 1 and A 2 are coaxial and a distance d apart. Points A, B are diametrically opposed points on the boundary of area A 1 . Points C′, D′ are diametrically opposed points on the boundary of area A 2 , with D′ the nearest point to B and C′ the nearest point to A. If A 1 is a source of light and A 2 is an aperture through which light from A 1 escapes, the étendue of that light is given by U=n 2 (π/4)([A,D′]−[A,C′]) 2 where [X,Y] denotes the distance between X and Y and n the refractive index of the medium in which A 1 and A 2 are immersed. If A 1 is a Lambertian source, the étendue it emits is U 1 =πn 2 A 1 . An ideal optic that recirculates through A 1 the light emitted by A 1 , in such a way as to force this radiation to come out through area A 2 , will then also reduce the étendue of the radiation by a factor of U/U 1 . The luminance of the emitted light will increase accordingly.
[0064] FIG. 6 shows the theoretical brightness increase of an elliptical reflector based on embodiment of FIG. 1 . FIG. 6 shows graph 16 with horizontal axis 17 , representing the reflectivity of the LED in % varying from 0 to 100%, and vertical axis 18 , representing the fractional increase in brightness of the LED light source. It is assumed that the average reflectivity of the surfaces of the elliptical reflector is 98%. For an average LED reflectance of 70% there is an increase in brightness by a factor of just over two from the original LED. As modern LEDs have reflectivity in the visible spectrum approximately 70% this indicates that a two-fold luminance increase should be attainable.
[0065] FIG. 7 shows an axial cross-section view of the device used in the ray-tracing model that generated the results shown in FIG. 6 . The size of exit aperture for the elliptical reflector 17′ of FIG. 7 is shown by dimension d 1 . The height of the exit aperture above the LED 18′ is shown by dimension h. FIG. 8 shows in plan view the position of the foci 19 ′ for the elliptical reflector of FIG. 7 relative to the LED.
[0066] FIG. 9 shows a further embodiment of a collimating system 20 , comprising flat light source 21 , a lens 22 that may be similar to an embodiment shown in the above-referenced U.S. Pat. No. 6,639,733 to Miñano et al., and elliptical mirrors 23 that return light to source 21 , enhancing the brightness of source 21 as seen by lens 22 .
[0067] FIG. 10 shows an axially symmetric collimating system 30 , comprising flat LED source 31 , lens 32 , and cylindrical sleeve 33 with retroreflecting external facets having a mirror coating. Sleeve 33 causes light source 31 to have enhanced luminance for lens 32 .
[0068] FIG. 11 shows a similar collimating system 40 , comprising flat LED source 41 , collimating Fresnel lens 42 , and cylindrical sleeve 43 , also shown in two close-up views including edge rays 44 , which can be seen being refracted by inner surface 43 i and retroreflected by outer faceted surface 43 f , a second-surface mirror. In particular, ray 44 d proceeds outward from the edge of light source 41 and is reflected as ray 44 r back to the opposite edge.
[0069] FIG. 12 shows a compound parabolic concentrator (CPC) 50 , with flat light source 51 and flowlines 52 . Annular reflector 53 covers part of the CPC exit, returning light to source 51 . Edge rays 59 show the angular beamwidth of CPC 50 before the beamwidth is reduced by reflector 53 .
[0070] FIG. 13 shows truncated CPC 54 , with annular reflector 55 following a line normal to the flowline curves. Reflective parabolic surface 56 between light source 51 and reflector 55 in FIG. 13 corresponds to the bottom half of the parabolic surface in FIG. 12 . Edge rays 59 in FIG. 13 are at the same beamwidth angle as edge rays 59 in FIG. 12 , but bound the actual beamwidth passing through the central aperture of reflector 55 .
[0071] FIG. 14 shows more truncated CPC 57 , replacing smooth parabolic profile 56 of FIG. 13 with Fresnel retroreflector 58 . Edge rays 59 show that all three configurations have the same beamwidth as the original CPC, in spite of their smaller apertures.
[0072] FIG. 15 shows a cross-section of dielectric total internally reflecting concentrator (DTIRC) 60 , comprising immersed LED source 61 , aspheric exit surface 62 , and totally internally reflecting quasi-conical side wall 63 . Edge rays 64 are refracted at exit surface 62 into étendue-limited beamwidth 65 .
[0073] FIG. 16 shows DTIRC 60 of FIG. 15 with a family of flowlines inside its dielectric medium which are drawn to scale. Also shown are the flowlines and ortho-flowlines chosen from a family of lines to form the boundary curves for a three-tier retroreflector. The six boundary curves for the retroreflector are shown starting from the top of the cross-sectional view of the original DTIRC and are labeled 60 a (an ortho-flowline), 60 b (a flowline), 60 c (an ortho-flowline), 60 d (a flowline), 60 e (an ortho-flowline) and 60 f (a flowline). These curves are used to create the retroreflector shown in FIG. 18 . This is done by sweeping the set of boundary curves about the central axis of the DTIRC optic. Note that the boundary curves are all attached to each other. Also it is possible to create a different family of flowlines and ortho-flowlines inside the DTIRC than the ones drawn in FIG. 16 . A new retroreflector can be created from the new orthogonal sets of lines by choosing any paired set (one flowline and an attached ortho-flowline) of attached boundary curves that connect along length of the original optic. Any number of design solutions is possible using this flexible approach.
[0074] FIG. 17 shows a cross section of dielectric retroreflective collimating system 70 having four tiers, comprising immersed LED source 71 , truncated aspheric exit surface 72 , and retroreflective mirror-coated faceted sidewall 73 . Beamwidth 75 is the same as beamwidth 65 of FIG. 15 , in spite of the reduced aperture of exit surface 72 compared with exit surface 62 .
[0075] FIG. 18 is a perspective view of a three tier retroactive collimating system 77 based on the flowlines and ortho-flowlines for DTIRC 60 of FIG. 16 . The boundary curves for an axial section of collimating system 77 are marked in bold line on FIG. 16 The coordinates for the boundary curves for this design are provided in the following Table 1 and Table 2). Table 1 gives the x,y (the y-value is the vertical measurement) coordinates for boundary curves 60 a , 60 b and 60 c , respectively from left to right in the table. Table 2 gives the x,y coordinates for boundary curves 60 d , 60 e and 60 f , respectively left to right.
[0076] FIG. 19 shows a cross section of dielectric retroreflective collimating system 70 ′ having five tiers, comprising immersed LED source 71 , truncated aspheric exit surface 72 , and retroreflective mirror-coated faceted sidewall 73 ′. Beamwidth 75 is the same as beamwidth 65 of FIG. 15 , in spite of the reduced aperture of exit surface 72 . The four upper tiers are similar to the collimating system 70 shown in FIG. 17 . The tier closest to the LED source 71 is elliptical, and may be centered on the source 71 as described with reference to FIG. 1 . In the embodiment of FIG. 19 , the sidewall 73 ′ does not cross the LED edges, making easier manufacturing.
[0077] The devices shown in FIGS. 12 to 16 may be modified by adding an elliptical bottom tier similarly to FIG. 19 .
[0000]
TABLE 1
refractive surface 60a
flowline 60b
upper reflector 60c
x
y
x
y
x
y
0.005601
12.53944
1.716114
12.27004
1.210033
7.444959
0.058138
12.53914
1.667029
11.80874
1.273561
7.438215
0.11627
12.53824
1.620984
11.37481
1.384193
7.425573
0.174389
12.53673
1.577689
10.96568
1.493433
7.411949
0.232489
12.53462
1.536888
10.57912
1.601198
7.397372
0.290565
12.5319
1.498357
10.21314
1.707409
7.381869
0.348609
12.52858
1.461898
9.865984
1.81199
7.365471
0.406615
12.52466
1.427336
9.536111
1.819595
7.364233
0.464578
12.52014
1.394513
9.222134
0.52249
12.51502
1.36329
8.922821
0.580347
12.50929
1.333542
8.637066
0.63814
12.50297
1.305155
8.363878
0.695865
12.49605
1.27803
8.102362
0.753515
12.48852
1.252073
7.851712
0.811084
12.4804
1.227203
7.611197
0.868565
12.47168
1.210033
7.444959
0.925953
12.46237
0.983241
12.45246
1.040423
12.44195
1.097493
12.43086
1.154445
12.41917
1.211272
12.40689
1.267969
12.39402
1.324529
12.38057
1.380946
12.36652
1.437215
12.35189
1.493328
12.33668
1.549281
12.32089
1.605067
12.30452
1.66068
12.28757
1.716114
12.27004
[0000]
TABLE 2
flowline 60d
lower reflector 60e
flowline 60f
x
y
x
y
x
y
1.819595
7.364233
1.240887
3.830033
1.962563
3.654924
1.810273
7.307064
1.257388
3.827189
1.940394
3.585854
1.783886
7.145132
1.273825
3.824306
1.896927
3.450582
1.758331
6.98816
1.290197
3.821384
1.854616
3.319194
1.733562
6.835885
1.306502
3.818423
1.813358
3.191447
1.709536
6.688068
1.322738
3.815424
1.773065
3.067138
1.686212
6.544483
1.338905
3.812388
1.733658
2.946098
1.663553
6.404923
1.355001
3.809316
1.69507
2.828184
1.641524
6.269195
1.371025
3.806208
1.657242
2.713278
1.620093
6.137118
1.386976
3.803066
1.620121
2.60128
1.59923
6.008527
1.402852
3.799889
1.583665
2.492107
1.578906
5.883264
1.418652
3.79668
1.547832
2.385689
1.559095
5.761184
1.434374
3.793437
1.512589
2.281967
1.539771
5.642152
1.450018
3.790163
1.477906
2.180894
1.520913
5.526039
1.465582
3.786859
1.443757
2.082428
1.502496
5.412728
1.481065
3.783524
1.410119
1.986534
1.484502
5.302107
1.496465
3.78016
1.376975
1.893184
1.466911
5.194073
1.511782
3.776768
1.344307
1.802352
1.449703
5.088527
1.527014
3.773348
1.312103
1.714015
1.432863
4.985379
1.542159
3.769901
1.280352
1.628155
1.416373
4.884542
1.557218
3.766429
1.249047
1.544753
1.400219
4.785937
1.572187
3.762932
1.218181
1.463793
1.384385
4.689488
1.587067
3.759411
1.187752
1.385258
1.368857
4.595124
1.601856
3.755867
1.157757
1.309134
1.353622
4.50278
1.616552
3.752301
1.128198
1.235404
1.338668
4.412393
1.631156
3.748713
1.099078
1.164051
1.323982
4.323904
1.645664
3.745106
1.070401
1.095061
1.309553
4.23726
1.660077
3.741478
1.042174
1.028414
1.295369
4.152409
1.674393
3.737832
1.014406
0.964093
1.281421
4.069303
1.68861
3.734169
0.987107
0.902078
1.267698
3.987899
1.702729
3.730489
0.96029
0.842349
1.254189
3.908155
1.716747
3.726794
0.933969
0.784884
1.240887
3.830033
1.730663
3.723083
0.90816
0.729662
1.744477
3.71936
0.882881
0.676658
1.758187
3.715623
0.85815
0.625849
1.771792
3.711875
0.83399
0.577208
1.785291
3.708115
0.810422
0.53071
1.798683
3.704346
0.787471
0.486328
1.811967
3.700569
0.765163
0.444036
1.825142
3.696783
0.743525
0.403806
1.838206
3.692991
0.722585
0.365612
1.851159
3.689193
0.702373
0.329425
1.864
3.685391
0.682919
0.29522
1.876728
3.681584
0.664256
0.262971
1.889341
3.677775
0.646417
0.232654
1.901839
3.673965
0.629433
0.204246
1.91422
3.670154
0.613341
0.177724
1.926484
3.666343
0.598172
0.153069
1.93863
3.662534
0.583963
0.130265
1.950657
3.658727
0.570746
0.109296
1.962563
3.654924
0.558556
0.090152
0.547426
0.072823
0.537388
0.057306
0.528472
0.043601
0.520707
0.031712
0.514121
0.021647
0.508738
0.013421
0.504579
0.007054
0.501662
0.00257
0.5
8.71E−15
[0078] FIG. 20 shows a cross-section of airgap RXI collimating system 80 , similar to an embodiment shown in the Falicoff '306 patent. LED package 81 is placed at the center of collimating lens 82 . Package 81 emits ray-fan 84 , which is transformed into étendue-limited collimated beam 85 . Lens 82 comprises interior surface 82 i receiving ray-fan 84 , front surface 82 f that totally internally reflects light back downward on a folded path, and mirror-coated rear surface 82 r which sends the light back up, whence it exits surface 82 f.
[0079] FIG. 21 shows a cross-section of truncated airgap RXI collimating system 90 , operating with identical LED package 91 , and lens 92 that is truncated by vertically disposed retroreflector 96 . The part of ray-fan 94 that would strike retroreflector 96 directly is recycled by reflector coating 97 on interior surface 92 i of lens 92 , so the surface here has a different shape than does surface 82 i of FIG. 20 . Surfaces 92 f and 92 r correspond to surfaces 82 f and 82 r in FIG. 20 . Retroreflector 96 thus recycles light from the outer part of internally reflecting surface 92 f . Alternatively, the corresponding parts of the exterior surface of the LED 91 can be mirrored. Output beam 95 has the same beamwidth as beam 85 of FIG. 20 , in spite of the smaller aperture.
[0080] FIG. 22 shows collimating system 100 , similar to one shown in the Falicoff '306 patent, comprising LED source 101 and collimating lens 102 . Exemplary ray 103 proceeds to faceted interior surface 102 i in which the facets have horizontal lower surfaces and conically slanted upper surfaces. Ray 103 enters upwards through a lower surface, and is then totally internally reflected laterally by the associated conical surface, out to one of outer slanted surfaces 102 f , which totally internally reflects ray 103 upward so it exits out horizontal surface 102 e . Lens 102 also comprises refracting drum lens 102 D that directs the lower rays horizontally to the lowest slanted surface 102 f . The overall shape of lens 102 is such that source 101 subtends a nearly constant apparent angular diameter from the various positions on the interior surface 102 i.
[0081] FIG. 23 shows truncated collimating system 110 , comprising LED source 111 and collimating lens 112 . Rays striking the upper part of interior surface 102 i are directed outward and upward as in FIG. 22 . However, lower slanted surfaces 102 f are replaced by pairs of facing slanted surfaces 114 , forming retroreflective V-grooves. Exemplary rays 113 are directed outwards by interior surface 102 i , as in FIG. 22 , but retroreflective V-grooves turn them back so they can rejoin source 111 . The grooves need no reflective coating. Lens 112 has the same beamwidth as lens 102 of FIG. 22 , in spite of the smaller aperture.
[0082] FIG. 24 shows another embodiment, collimating system 120 , which is similar to one shown in the Falicoff '306 patent, and comprises LED light source 121 and collimating lens 122 , similar to lens 112 of FIG. 23 except for domed upper collimating lens 122 L.
[0083] FIG. 25 shows truncated collimating system 130 , also comprising retroreflecting lateral V-grooves 134 , which cause light to be returned to LED light source 131 .
[0084] FIG. 26 shows a luminaire similar to that of FIG. 11 , but with the addition of mushroom lens 143 , the central concavity of which acts as a negative lens to demagnify the image of LED light source 141 and thereby reduce output beamwidth from its étendue-limited value.
[0085] FIG. 27 shows elliptic reflector 150 made of micro linear retroreflectors 152 whose grooves are lines normal to the flowlines, either ridges 153 or valleys 154 . Light striking anywhere on the interior of reflector 150 is retroreflected by the two facets either side of a ridge 153 . Luminance enhanced light exits through central aperture 155 . The inner part of the retroreflectors is a dielectric with a refractive index high enough to produce retroreflection by TIR of the rays coming from the LED surface or other suitable source. The whole elliptic cavity can be filled by a dielectric or the reflector can include another elliptic cavity filled with air (n=1). In this latter case the inner surface is elliptic without micro grooves. Such micro linear retroreflectors can be used in any surface generated from curves normal to the flowlines and not only in the elliptical cavity, at least if the flowlines intersected by each such curve form a plane surface. That is the case for the meridian ellipses of FIG. 1 , where the flowlines intersecting each meridian form a radial and axial plane containing the meridian in question. The advantage of using such linear retroreflectors is that the reflectivity can increase as the metallization process can be avoided. Note that in general the reflecting surfaces containing flowlines can work by TIR.
[0086] To calculate the surface of the micro linear reflectors the following procedure can be used: Let P=C(u) be the parametric equation of the line normal to the flowlines (u is the parameter along the curve). Let t p be the unit tangent to the curve at P and let j p be the unit tangent to the flowline passing through P. Note that j p ·t p =0 (i.e., these 2 vectors are perpendicular). The 2 slopes of the groove are given by the following parametric equations: P=C(u)+v(j p ±j p ×tp) where × denotes the cross product of two vectors and where u and v are the parameters on the surface. Both vectors j p and t p depend on the parameter u. This surface coincides with the surface normal to the flowlines at least at v=0. Each side of the groove is limited by its intersection with its neighbor groove. If the surface is not too big, the local behavior of the groove is that of a linear retroreflector with axis t p .
[0087] These retroreflectors are different from those shown in FIG. 23 , the retroreflectors 114 shown in FIG. 23 having rotational symmetry.
[0088] FIG. 28 shows a cutaway view of elliptic reflector 150 , cut by a meridian plane to reveal disc source 151 , with diameter 156 revealing that the bottom of reflector 150 is coplanar with source 151 , which as previously is diffusely reflecting to recycle the light returned by reflector 150 .
[0089] It is desirable that the reflectance of the retro-reflectors be as high as possible in order to achieve a significant boost in brightness and at the same time maintain a high efficiency. It is well known in the thin film industry how to achieve high reflectance using multi-dielectric coatings or hybrid metal/dielectric coatings (where the metal is either aluminum or silver) when the reflector operates with the incident and reflected rays in air, and a solid support on the inactive side of the coating. These so-called first surface reflectors can be designed to operate within a certain range of ray incidence angles and wavelengths. However, prior art is limited with regard to high performance designs for second surface reflectors that are needed for efficient implementation of many of the embodiments in this invention, such as the design of FIG. 18 . The typical prior art design only achieve an average reflectance of 90%. The following thin film design shown in Table 3 addresses this issue and provides a formula for an omni-directional second surface reflector having a reflectance in the visible and near infrared range of over 95%.
[0090] The key principle used to design this reflector is revealed in U.S. utility application Ser. No. 11/982,492 “Wideband Dichroic-Filter Design for LED-Phosphor Beam-Combining” filed on Nov. 2, 2007 (by one of the Inventors of this invention), which is incorporated herein by reference in its entirety. In order to increase the reflectance an initial low index layer such as silicon dioxide is used as the first layer of a stack applied to the dielectric medium of the optic. The thickness of this layer should be no less than two times the shortest wavelength of light source that needs to be highly reflected. A nominal thickness of 1000 nm to 1100 nm works well for visible light sources. This thickness is later optimized using a thin film design software package such as Essential Macleod once a merit matrix is established for the design. A preferred design is shown in the following table starting from the dielectric medium (assumed to be acrylic) backwards towards air. The materials are in order of deposition on the second surface, Silicon Dioxide, Tantalum Pentoxide, Silicon Dioxide, Silver, Copper (protects silver from degradation), Inconel (a proprietary metal of Special Metals Corporation of New Hartford, New York. The last layer protects the silver and copper layers. The overall thickness of the stack is just under 1.7 microns. Note that the first Silicon Dioxide layer is slightly under 1100 nm.
[0000]
TABLE 3
Design: second surface
Reference Wavelength (nm): 530
Incident Angle (deg): 0
Optical
Physical
Packing
Refractive
Extinction
Thickness
Thickness
Geometric
Layer
Material
Density
Index
Coefficient
(FWOT)
(nm)
Thickness
Medium
Acrylic
1.49472
0
1
SiO2
1
1.46085
0
2.965255
1075.8
2.029818
2
Ta2O5
1
2.02
0
0.974106
255.58
0.482231
3
SiO2
1
1.46085
0
0.161577
58.62
0.110605
4
Ag
1
0.053
3.14
0.01925
192.5
0.363211
5
Cu
1
0.754
2.7675
0.06965
48.96
0.092375
6
Ni
1
1.821
3.211
0.171414
49.89
0.094132
Substrate
Air
1
0
Total Thickness
4.361252
1681.36
3.172371
[0091] The reflectance values (for the mean polarization state) were set to 1.0 for all wavelengths from 420 nm to 700 nm in the Macleod target matrix. FIG. 29 shows graph 160 which gives the % reflectance (vertical axis) of the second surface thin film reflector at 0° incidence angle for the wavelength (horizontal axis) band from 350 nm to 700 nm. The reflectance starts at 95% for 410 nm and is above 97% for all wavelengths from about 425 nm up to 700 nm. A slightly higher performance is possible by employing conjugate gradient optimization or other forms of optimization known to those skilled in art of thin film design. For maximum performance a range of incidence angles and wavelengths should be used as the merit function. If more alternating layers of Silicon Dioxide and Tantalum Pentoxide are added to the design, the reflectance can be further increased to above 99% reflectance for a wide range of incidence angles and wavelengths. For high incidence angles (above the critical angle) the reflectance is theoretically 100% as the thick layer of Silicon Dioxide reflects light via total internal reflection.
[0092] FIG. 30 shows, in an axial cross-section view similar to FIG. 16 , a set of flowlines and ortho-flowlines for a further embodiment of a luminaire 300 . The luminaire 300 comprises a light source 301 and a collimating and retroreflecting optic 302 , bounded by a refractive exit surface 304 and reflective side surfaces 306 , 308 , 310 . The surfaces are surfaces of revolution of the lines shown in FIG. 30 about a central axis. Reflective surface 306 extends along a flowline from the edge of the refractive exit surface 304 towards the source 301 . Retroreflective surface 308 extends along an ortho-flowline from the proximal end of the reflective surface 306 towards the axis of luminaire 300 . Reflective surface 310 extends along a flowline from the inner edge of reflective surface 308 to the periphery of source 301 .
[0093] In order to show the geometry more clearly, the flowline on which surface 310 lies and the exit surface 304 have been extended to meet. These extended lines delineate a notional conventional collimating luminaire, with which the luminaire 300 of FIG. 30 may be compared. The retroreflective surface 308 permits the size of the exit aperture 304 , and the overall size of the optic 302 to be reduced relative to the notional comparison luminaire, while maintaining the angular beamwidth 312 equal to that of the notional comparison luminaire.
[0094] The shapes of the active surfaces of optic 302 are shown in Tables 4 and 5 as a series of plots of x,y coordinates along each of the lines 304 , 306 , 308 , 310 , taking the plane of the source 301 as y=0 and the central axis as x=0.
[0000]
TABLE 4
Exit surface 304
Flowline 306
x
y
x
y
0.002843
5.581988
1.306941
5.263837
0.045264
5.581627
1.288433
5.159707
0.090516
5.580546
1.270654
5.059171
0.135746
5.578745
1.253555
4.962001
0.180941
5.576225
1.237094
4.867987
0.22609
5.572985
1.221229
4.776939
0.271182
5.569027
1.205925
4.688679
0.316206
5.564351
1.191148
4.603044
0.361149
5.55896
1.176865
4.519884
0.406
5.552853
1.163049
4.43906
0.450749
5.546034
1.149673
4.360443
0.495384
5.538503
1.136711
4.283913
0.539893
5.530262
1.124141
4.20936
0.584265
5.521314
1.111942
4.13668
0.628489
5.511661
1.100093
4.065779
0.672554
5.501305
1.088577
3.996566
0.716448
5.490249
1.077376
3.928959
0.760161
5.478496
1.066473
3.86288
0.803681
5.466048
1.055854
3.798258
0.846998
5.452909
1.045505
3.735023
0.890099
5.439082
1.035413
3.673113
0.932976
5.424571
1.025565
3.612469
0.975616
5.409379
1.01595
3.553035
1.018008
5.39351
1.006556
3.49476
1.060143
5.376969
0.997375
3.437594
1.102009
5.359758
0.988395
3.381493
1.143596
5.341884
0.979609
3.326412
1.184893
5.32335
0.971007
3.272312
1.225889
5.30416
0.962582
3.219154
1.266576
5.284321
0.954326
3.166903
1.306941
5.263837
0.946232
3.115526
0.938293
3.064991
0.930502
3.015267
0.922855
2.966327
0.915344
2.918145
0.907964
2.870695
0.900711
2.823954
0.89358
2.7779
0.886565
2.732512
0.879662
2.687769
0.872867
2.643654
0.866176
2.600149
0.859586
2.557237
0.853092
2.514903
0.84669
2.473131
0.840379
2.431908
0.834153
2.39122
0.828011
2.351055
0.82195
2.311401
0.815965
2.272247
0.810056
2.233582
[0000]
TABLE 5
Ortho-flowline 308
Flowline 310
x
y
x
y
0.810056
2.233582
1.318804
2.114914
0.821841
2.23176
1.318039
2.112537
0.833573
2.229906
1.299096
2.053679
0.845251
2.228019
1.280508
1.995877
0.856875
2.2261
1.262239
1.939055
0.868444
2.224151
1.244258
1.883153
0.879957
2.222171
1.226536
1.828115
0.891412
2.220161
1.209048
1.773899
0.90281
2.218122
1.191774
1.72047
0.914149
2.216054
1.174693
1.667798
0.925428
2.213959
1.157788
1.615861
0.936646
2.211836
1.141046
1.564641
0.947804
2.209686
1.124452
1.514124
0.958899
2.20751
1.107994
1.464301
0.969931
2.205309
1.091664
1.415165
0.980899
2.203083
1.075451
1.366713
0.991802
2.200833
1.059349
1.318943
1.00264
2.198559
1.04335
1.271858
1.013412
2.196263
1.027449
1.225458
1.024116
2.193945
1.011641
1.179749
1.034753
2.191605
0.995923
1.134734
1.045321
2.189244
0.980292
1.090421
1.055819
2.186863
0.964746
1.046815
1.066248
2.184463
0.949283
1.003925
1.076605
2.182044
0.933903
0.961757
1.086891
2.179607
0.918607
0.92032
1.097104
2.177153
0.903395
0.879622
1.107245
2.174682
0.888269
0.83967
1.117311
2.172195
0.873231
0.800472
1.127303
2.169693
0.858285
0.762036
1.13722
2.167177
0.843433
0.724369
1.14706
2.164647
0.828681
0.687479
1.156825
2.162103
0.814033
0.651372
1.166512
2.159548
0.799495
0.616055
1.176121
2.156981
0.785073
0.581534
1.185651
2.154402
0.770774
0.547814
1.195103
2.151814
0.756606
0.5149
1.204475
2.149216
0.742576
0.482797
1.213767
2.14661
0.728694
0.451508
1.222977
2.143995
0.714968
0.421039
1.232107
2.141373
0.70141
0.391391
1.241154
2.138745
0.688028
0.362567
1.250119
2.136111
0.674834
0.334571
1.259
2.133471
0.661839
0.307403
1.267798
2.130828
0.649057
0.281066
1.276512
2.12818
0.636498
0.255561
1.285142
2.12553
0.624176
0.230888
1.293686
2.122877
0.612105
0.207049
1.302145
2.120223
0.600299
0.184045
1.310517
2.117568
0.58877
0.161875
1.318804
2.114914
0.577535
0.14054
0.566607
0.120041
0.556001
0.100377
0.545734
0.081551
0.53582
0.063561
0.526274
0.04641
0.517112
0.030098
0.508349
0.014627
0.5
−1.89E−15
[0095] The preceding description of presently contemplated modes of practicing the invention is not to be taken in a limiting sense, but is made merely for the purpose of describing the general principles of the invention.
[0096] For example, the source of radiation has been described in the embodiments as a flat, square or circular, light emitting diode (LED). LED sources are described because LED sources with the desired properties, including high luminous efficiency and diffuse reflectance of light of the same frequencies as the light emitted, are readily obtainable from commercial sources. However, other light sources currently available or to become available in the future may be used instead. Flat, square or circular sources are described in the embodiments because LED sources with that configuration are readily obtainable from commercial sources, and because the resulting geometrical simplicity of the examples is believed to aid in understanding of the underlying principles. However, light sources of other shapes may be used.
[0097] For example, some embodiments have been described with reference to the orientation shown in the drawings, using relative language such as “top” and “bottom.” However, the described luminaires may be used in other orientations.
[0098] The full scope of the invention should be determined with reference to the claims.
[0099] The following additional U.S. Patent documents are believed to be relevant to understanding of the invention, and are incorporated herein by reference in their entirety.
[0100] U.S. Pat. No. 5,684,354 to Gleckman
[0101] U.S. Pat. No. 5,892,325 to Gleckman
[0102] U.S. Pat. No. 6,043,591 to Gleckman
[0103] U.S. Pat. No. 6,496,237 to Gleckman
[0104] U.S. Pat. No. 6,960,872 to Beeson & Zimmerman
[0105] U.S. Pat. No. 6,869,206 to Beeson & Zimmerman
[0106] U.S. Pat. No. 7,025,464 to Beeson & Zimmerman
[0107] U.S. Pat. No. 7,040,774 to Beeson & Zimmerman | The diffuse reflectivity of an LED source is utilized to recycle some of its emission, thereby enabling a luminaire to escape the étendue limit. Retroreflectors intercept the rays destined for the outer part of the luminaire aperture, which can then be truncated. The resulting smaller aperture has the same beam-width as the full original, albeit with lesser flux due to recycling losses. A reduction to half the original area is possible. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a method of and an apparatus for measuring and adjusting the wheel alignment of automotive vehicles.
2. Prior Art
Wheel alignment of four-wheeled automotive vehicles such as passenger cars, buses and trucks is effected conventionally with all of the four wheels mounted on respective rotary drums in a wheel alignment testing apparatus and rotated at a predetermined rate of speed, whereupon the toe-in or camber of each wheel is checked and adjusted to the manufacturer's specifications. In such instance, it is essential to see to it that the wheels are mounted on the respective drums with the center line of the vehicle axle registered with the longitudinal center line of the testing apparatus. Failing this would result in misaligned wheels and hence defective drive performance.
A prior art approach has been proposed in which a pair of oppositely disposed limiter arms are used to restrict lateral shift or displacement of each of the front and rear wheels in a direction transverse to the center line of the testing apparatus after the vehicle is mounted and brought into center-to-center registry with the apparatus. This approach however has a drawback firstly in that it is cumbersome and time-consuming to guide the vehicle as by an equalizer into proper registration with the testing apparatus and secondly in that because of coercive positioning the wheels against inherent axial movement with respect to the rotary drums, undue stress is imposed on the wheels which would hinder accurate measurement of wheel alignment approximating actual on-road performance.
SUMMARY OF THE INVENTION
With the foregoing drawbacks of the prior art in view, the object of the present invention is to provide a method and an apparatus for measuring and adjusting the wheel alignment of an automotive vehicle which will enable efficient and accurate alignment of the vehicle wheels in strict conformance with the manufacturer's specification settings.
More specifically, the invention provides such method and apparatus which will eliminate the need for mounting the vehicle in exact centering registry with an alignment testing apparatus prior to wheel alignment adjustment.
The invention further provides such method and apparatus which are capable of measuring and adjusting the vehicle wheel alignment with high precision under conditions closely approximating actual on-road running performance.
The above and other objects and features of the invention will be better understood from the following detailed description taken with reference to the accompanying drawings which illustrates by way of example a preferred embodiment which the invention may assume in practice. According to the invention, there is provided a method of measuring and adjusting the wheel alignment of a four-wheeled automotive vehicle which comprises the steps of: (a) rotating the front and rear tires of the vehicle on respective roller units which are held for free horizontal movement longitudinally of the vehicle; (b) bringing the outer side walls of both the front tires into pressure contact with a first sensor unit and restricting axial movement of the front tires; (c) measuring the pressure developed on contact of the front tires with the first sensor unit; (d) measuring the toe-in angle of each of the front and rear tires; (e) adjusting the toe-in angle of each of the rear tires to the specification until the pressure measured in step (c) becomes zero; and (f) adjusting the toe-in angle of each of the front tires.
An apparatus for carrying the above method into practice according to the invention comprises: a roller unit disposed for free horizontal movement longitudinally of the vehicle and including rollers engageable with the tread of each of the front and rear tires, a means of driving the rollers to rotate with each of the front and rear tires, a first sensor unit having means of restricting axial movement of the front tires and means of measuring the pressure developed on contact of the restricting means with the front tires, the restricting means being connected at one end to a pivotal link, and a second sensor unit movable horizontally toward and away from the center line of the apparatus and having a detecting means of detecting a toe-in angle of each of the front and rear tires, the detecting means including an optical displacement sensor, a tiltable disc member disposed in confronting relation to the displacement sensor and a plurality of rollers supported on the tiltable disc member and engageable with the side wall of each of the front and rear tires.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view of a wheel alignment testing apparatus embodying the invention with a vehicle mounted thereon as indicated in phantom lines;
FIG. 2 is a side elevational view of the same;
FIG. 3 schematically illustrates a displacement sensor unit incorporated in the apparatus of FIG. 1;
FIG. 4 schematically illustrates a toe-in or camber sensor unit incorporated in the apparatus of the invention;
FIG. 5 is a schematic plan view of the apparatus utilized to explain the operations of the displacement and toe-in or camber sensor units; and
FIGS. 6A-6C inclusive are schematic diagrams utilized to explain the method of measuring and adjusting a vehicle wheel alignment according to the invention. Like reference numerals refer to like or corresponding parts throughout the several views.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings and FIGS. 1 and 2 in particular, there is shown a wheel alignment testing apparatus 10 which comprises a machine frame 11 including an upper horizontal support frame member 12 and a lower horizontal support frame member 13 interconnected by vertical side support frame members 14, 14. The upper frame member 12 is cut out at one or front end to provide a first compartment 15 for accommodating a first or front pair of roller units 16a, 16b and at the opposite or rear end to provide a second compartment 17 for accommodating a second or rear pair of roller units 18a, 18b, the second compartment 17 being larger in spatial size than the first compartment 15 for purposes later described.
The first pair of roller units 16a , 16b, and the rear pair of roller units 18a, 18b are mounted on respective front and rear movable racks 19 and 20 which are movable horizontally slidably on and along respective guide rails 21 and 22 secured to a longitudinally extending intermediate frame member 23. Thus, each of the roller units 16, 18 is movable to and fro in parallel to a longitudinal center line CT of the testing apparatus 10 or a center line CV of a vehicle axle not shown.
In the presently illustrated embodiment of the invention, either one of the front roller units 16a, 16b is held stationary horizontally while the other front roller unit is disposed for free horizontal sliding movement as above described, although all of the front roller units 16a, 16b and the rear roller units 18a, 18b may be supported for free sliding movement for the purpose of the invention.
The rear rack 20 is connected to a third movable rack 24 which is movable horizontally slidably on and along a guide rail 25 secured to the lower frame member 13.
A first fluid-operated cylinder 26 is mounted on the lower frame member 13 with its piston rod 26a disposed in abutting engagement with the third rack 24. Actuation of the cylinder 26 causes the rack 24 to move horizontally in either direction within the second compartment 17 so as to adjust the distance between the front and rear roller units 16a, 16b and 18a, 18b to the wheel base of a given vehicle V to be tested.
Each of the roller units 16a, 16b and 18a and 18b comprises a drive roller 27 and an idler roller 28 both of which are vertically movable into and out of peripheral engagement with the treads of the corresponding front tires 29a, 29b or rear tires 30a, 30b of the vehicle V. This vertical movement of the rollers 27 and 28 is effected by a lift 31 disposed between the drive rollers 27 and the idler rollers 28 and vertically movable toward or away from the vehicle tires by means of a second fluid-operated cylinder 32 to allow the vehicle V to set in testing position or to be removed from the apparatus 10.
The drive rollers 27 are driven by respective motors M via drive belts 33 and adapted in turn to drive the vehicle tires at any predetermined rate of speed under conditions simulating actual on-road performance. Referring now to FIG. 3 in particular, there is shown a first sensor unit or a wheel displacement sensor unit 34 provided in a position corresponding to the location of each of the front roller units 16a, 16b and generally comprising a third fluid-operated cylinder 35, a fourth fluid-operated cylinder 36, a load-cell 37, and a pressure meter 38. The third cylinder 35 is connected at one end with its piston rod 35a to a sensor roller 39 and at the opposite end to a support bracket 40 through a link 41 which is pivotally interconnected therebetween. The fourth cylinder 36 has its piston rod 36a engageable with a connecting bracket 35b of the third cylinder 35. A forward stroke of the piston rod 36a causes the third cylinder 35 to move toward the center line CL of the apparatus 10 until the sensor roller 39 comes into abutting engagement with the outer side wall of the front tire 29a (29b), whereupon the third cylinder 35 is locked, thereby restricting axial movement of the front tires 29a, 29b, followed by a backward stroke or retraction of the piston rod 36a of the fourth cylinder 36. When the front tires 29a and 29b are rotated, either of them tends to drift or swerve sideways and urges the third cylinder 35 backward through the pivotal movement of the link 41 so that the opposite end of the cylinder 35 remote from the sensor roller 39 is brought into pressure engagement with the load-cell 37, the pressure developed thereat being read by the pressure meter 38.
A second sensor unit or a toe-in sensor unit 42 provided in accordance with the invention is located above and in parallel with each of the roller units 16a, 16b and 18a, 18b for measuring the toe-in of the vehicle V, as shown in FIGS. 1, 2, 4 and 5. The second sensor unit 42 comprises, as better shown in FIG. 4, a sensor frame 43 which is movable horizontally slidably on and along a guide rail 44 secured to the upper frame member 12 of the machine frame 11, a fifth fluid-operated cylinder 45 having its piston rod 45a connected to the sensor frame 43, a pair of optical displacement sensors 46 attached at the upper and lower ends of the sensor frame 43, a tiltable or deflective disc 47 connected centrally through a universal joint 48 to the sensor frame 43 in confronting relation to the sensors 46 and a plurality (three in the illustrated embodiment) of rollers 49 rotatably supported on respective brackets 50 secured at predetermined or equally spaced intervals to the disc 47.
Actuation of the fifth cylinder 45 causes the rollers 49 to move into and out of engagement with the outer side wall of the tire 29a, (29b, 30a, 30b).
The amount of horizontal movement of the rollers 49 toward and away from each of the tires 29a, 29b, 30a, 30b is measured by a pinion and rack arrangement comprising a toothed rack 51 secured to the rear end of the sensor frame 43 and a pinion 52 rotatally engaged with the rack 51 and connected to a potentiometer 53 leading to a computer unit not shown.
The alignment measuring and adjusting apparatus 10 thus constructed operates in the following manner.
The first cylinder 26 is actuated to bring the rear roller units 18a, 18b into position registering with the rear wheels of the vehicle V, so that all of the vehicle wheels are mounted in their respective proper positions corresponding to the front and rear roller units 16a, 16b, 18a, 18b. The second cylinder 32 in each roller unit is then actuated to raise the lift 31 until the rollers 27 and 28 are brought into abutting engagement with the thread of the corresponding tire, at which time the vehicle V is positioned out of alignment with the center line CT of the apparatus 10 as exemplified in FIG. 6A.
The motors M are then put into operation to drive the roller 27, 28 which in turn rotate all of the four wheels or tires 29a, 29b, 30a, 30b, during which time the front roller unit 16a and the rear roller units 18a, 18b are allowed to move slightly back and forth in parallel to the center line CT and help balance out the tire positions. The speed of the motors M is now increased so that the vehicle wheels run under actual on-road conditions as schematically shown in FIG. 6B which represents the tire positions prior to alignment adjustment. This is followed by the operation of the displacement sensor units 34 in which the fourth cylinder in each unit is actuated to move the third cylinder 35 toward the center line CT until the sensor roller 39 comes into abutting engagement with the front tire 29a (29b) as shown in FIG. 3, in which instance the third cylinder 35 is held freely movable. The pressures developed on contact of the sensor rollers 39, 39 of the two parallel units 34, 34 with the front tires 29a, 29b are transmitted through the respective load-cells 37, 37 and read by the respective meters 38, 38.
All of the four toe-in sensor units 42 now put into operation in which the fifth cylinder 45 in each unit is actuated to move the sensor frame 43 toward the center line CT until the rollers 49 are brought into abutting engagement with the corresponding tire 29a (29b, 30a, 30b). Rotating contact between the rollers 49 and the corresponding tires 29a-30b in each of the four sensor units 42 produces angular or deflective movement of the tiltable disc 47, which movement is captured through the medium of a light beam and sensed by the displacement sensor 46 leading to a computer unit. At the same time, the amount of horizontal movement of each of the sensor units 42 is measured by the potentiometer 53 leading to the computer unit.
The operator is now ready to adjust the wheel alignment of the vehicle V in a manner well known in the art by first adjusting the total toe-in angle of the rear tires 30a, 30b to the specification setting with reference to the readings of the displacement sensors 46, thus registering the thrust angle X' (FIG. 6B) with the thrust angle X (FIG. 6C). This adjustment causes either one of the rear tires 30a, 30b to shift toward or away from the center line CT and corrects any displacement of the vehicle V with respect to the apparatus 10, thus bringing the center line CV of the former into alignment or parallel relation with the center line CT of the latter. This can be confirmed by the meters 38, 38 showing "O" reading, or conveniently by observing a lamp display indicating completion of the center-to-center alignment.
The steering wheel H is then set in straight run position as shown in FIG. 6C, followed by adjusting the total toe-in angle of the front tires 29a, 29b to the specification with reference to the readings of the displacement sensors 46, thus registering the center toe-in angle Y' (FIG. 6B) with the center toe-in angle Y (FIG. 6C).
In the illustrated embodiment, the front right roller unit 16b is held horizonatlly immovable while the roller units 16a, 18a, 18b are horizontally movable. This arrangement contributes to speedy alignment of the apparatus center line CT with the vehicle center line CV as the roller unit 16b serves as a reference point.
Obviously, various modifications and variations of the present invention are possible in the light of the above teaching. It is therefore to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described. | A method of measuring and adjusting the wheel alignment of an automotive vehicle comprises bringing all of the four tires in condition for actual on-road running performance, restricting axial movement of both of the front tires alone, measuring the toe-in angles of the front and rear tires and adjusting the toe-in angle of each of the rear tires to the specification whereby the center line of an alignment adjusting apparatus is brought into alignment or parallel relation to the center line or axis of the vehicle. An apparatus is also disclosed for reducing this method to practice. | 6 |
RELATED APPLICATIONS
This application is a continuation of U.S. application Ser. No. 10/916,117, filed Aug. 11, 2004, U.S. Pat. No. 7,140,806 to Wentworth et al.
TECHNICAL FIELD
The invention relates to underground pipe bursting and replacement systems of the static type which operate by pushing or pulling a string of rods to which a bursting head or other tooling is attached.
BACKGROUND OF THE INVENTION
Pipe bursting is a well known process that brings enormous potential for the efficient and unobtrusive replacement of buried pipelines. Currently the there are two widely used but separate systems used to accomplish pipe bursting. The choice of the system is most often dependent on the type of utility being upgraded.
Gravity sanitary sewer systems are made up of interconnected pipes buried at depths from (4) to (40) foot beneath the surface. These systems make use of ‘manholes’ to provide access for maintenance and cleaning of the interiors of the pipes. It is advantageous to minimize the damage and potential need for replacement of these manholes during the bursting operation. To do that requires practicing the method described in U.S. Pat. No. 6,299,382. That method calls for use of a pneumatic actuated tool, hydraulic winch with the guide cable passed through the existing pipe, and a front-mounted bursting head. Hence, primarily for that reason, most gravity sewer pipe bursting is done with pneumatic tools.
Potable water pipes are also widely in need of replacement. These systems, by the nature of the fact that they are pressure fed and therefore independent of the effects of gravity, tend to be buried at shallow depths in moderate climates. In addition, they do not have manholes, unlike the gravity sewer systems. For these reasons, water pipes are typically burst with a machine that requires an access pit at each end of the job. In the situation where there is no manhole present, having two access pits is not necessarily disadvantageous. The machine that fits this description is called a static system. Using significant hydraulically actuated force applied through a rod string, the tooling used on a static system splits the existing pipe and expands the surrounding soil. This style of bursting has four major components:
A. Tooling. This subsystem performs the function of cracking the pipe, expanding the adjacent soil with a conical form and a lastly provides a means of attachment of the product pipe to the rear of the tooling.
B. Rod String. The rods, threaded at each end, are engaged end to end into a string. This string transmits the pull force between the hydraulic pulling unit and the tooling.
C. Hydraulic power pack. This subsystem exists purely to provide pressurized hydraulic flow for operation of the pulling unit. The power pack may even be a hydraulic excavator configured to power auxiliary equipment as needed.
D. Downhole Unit. This is generally the most complex part of the machine; it entails the greatest amount of mechanism and complication of any of the four components. Hydraulic cylinders are employed to cyclically stroke a rod engagement system. The rod engagement may be through the threaded end, or by a mechanism that grips the rod outer surface or engages features on the outer surface. The engagement system-must grip or engage the rod and apply thrust force in one direction, while sliding freely along the length of the rod in the opposite direction. This system must have the capability of being shifted relative to direction of operation so that rods may be added to, or removed from the string. An optional subsystem in downhole unit is a device to aid in the threading and unthreading of rods.
Two known pit launch static bursting machines are known commercially as the McLaughlin pit launch and the Vermeer PL8000. These are low force (10,0000 lb) pulling machines having a hole approximately 8″ in diameter in the front of the machine to accept small backreamers into the machine. When this is done, the vise floats (moves) with the spindle to allow the tooling to enter the machine. Since the pulling force was low, the hole did not present major problems with respect to soil entry or shoring area. With higher pulling forces, providing a hole in the front shore plate of the machine becomes problematic because soil will tend to enter the machine through the hole.
SUMMARY OF THE INVENTION
The present invention relates to an improved static bursting system. According to one aspect of the invention, the system provides for plain bearing pullback without rotation, while allowing rotation during payout. Rod string rotation must be a feature of this design available during rod payout. In many applications where an existing line has collapsed, the rod string or winch rope cannot be passed through the collapsed section successfully. A system that rotates the drill string makes it possible to guide the unit through the collapse as rod is added using either a non-directional drill bit or a drill head as typically used in horizontal directional drilling (HDD).
While working through this collapsed section, modest axial thrust in the range of 1000 to 40,000 lb may be applied to the bit through the drill string during rotation. This allows the bit to displace material with the option of delivering drill fluid through the hollow drill string to float the soil out of the existing pipe. The thrust must be applied to the drill string through a bearing. Roller bearings of this capacity are moderately but not excessively large and costly.
Pullback is the process wherein rod is removed from the drill string, shortening the string. The tooling is progressively pulled through the existing pipe, cracking the pipe and expanding the local soil. During the process, the rod string is not rotated. Forces applied to the drill string are in the range of 60,000 to 250,000 lb, significantly greater than during rod payout. Bearings of this capacity are very large and costly. To avoid the encumbrance of these bearings, according to the invention, a plain load bearing flange is used instead. This bearing will not support rotation during pullback and will in fact cause the rotation motor to stall should rotation be attempted when high axial pullback forces are applied. To achieve a successful design in this style, the shaft should be free to float a short distance between being loaded on the payout direction against the roller bearing and being thrust against the plain bearing load flange in the pullback direction. This float may be small in magnitude, e.g. between 0.05 and 0.25 inch.
It is advantageous but not necessary to preload the shaft against the roller bearing when no load is applied to the rod string. This preload can be modest, in the 500 to 2000 lb range. It is best achieved with a preloaded spring, the spring is depressed a short percentage of its design travel in the installed condition. This preload does not change as axial thrust in the payout direction is applied. As axial thrust in the pullback direction is applied, the modest spring force is overcome and the spring compresses further. This allows axial movement of the shaft relative to the bearings. As the shaft moves through the short distance per the design, it soon contacts the plain bearing load flange.
According to the invention, the drill string is allowed to rotate during payout to drill through obstructions within a collapsed pipe. During pullback, the unit is unable to rotate the rod string, therefore rendering tooling such as back reamers that function with rotation unusable. Pullback tooling is therefore limited to conical expanders, blades and other devices that perform hole and pipe expansion via axial movement only.
The invention further provides a “bungee vise” that aids in extending or retracting the drill string. During both the payout and pullback phases of a bursting job, the movement of the rod is stopped momentarily to add or remove the last rod of the string. During this moment, there are residual forces applying an elastic load to the rod string. During payout, that elastic load may be due to an arced path that the existing pipeline follows, or it might be due to an obstruction encountered at the front of the rod. Because the rod string is small in diameter compared to the existing host pipe, any load will cause an imperceptible buckling that will disappear should the load be released. The buckling uses up a small percentage of the length of the rod string, as little as nothing or as great as 12 inches. Unloading of the rod during the period when the rod is stopped would cause the rod to thrust back this distance, resulting in location issues for rod thread up and causing wasted travel every time the process is repeated.
During pullback, the process is similar but opposite. The elastic load applied to the tooling by the product pipe will produce residual load even when the rod string has been halted and work done by the tooling has halted. If the rod is not secured while the last rod is being removed, then the string will be pulled by the elastic pipe forces back into the bore. This distance can be anywhere from nothing to 3 feet depending on the soil conditions.
In order to overcome these potential problems with residual load, a vise of the invention is configured to grip the rod string and provide frictional force due to high hydraulically induced clamping forces. In addition to the frictional force, should the residual loads be exceptionally high, the gripping jaws are configured to encounter a shoulder on the rod after a brief amount of axial slippage. This slippage is best kept to a minimum, preferably in the range of 0.10 to 0.25 inch, in order to limit damage to the gripped surfaces on the rod and jaw.
The vise is called on to do another task, that of restraining the rod string from rotating while the last rod is being rotated with significant torque to either add it to or remove it from the drill string. While the threading operation is in process, the vise holds the residual axial load of the string while simultaneously preventing the string from rotating as torque is applied to add or remove another rod.
A further aspect of the invention relates to the thrust cylinders. In a static bursting system, the rod thrust or pullback is normally applied to the rod string via actuation of hydraulic cylinders. Normally, hydraulic cylinders are designed in a manner where flexible hydraulic hoses are plumbed to the cylinder body through ports in the cylinder wall. Pressurized hydraulic fluid is fed to the cylinders through these ports and the cylinder rod is extended or retracted relative to the cylinder body as a function of which port the fluid is supplied to.
In the commonplace configuration just described, most mobile hydraulic equipment is assembled with the cylinder body fixed or pinned to the frame of the machine. Further, the rod, not the cylinder body, is permitted to extend or retract relative to that same frame. This works well in most cases as the flexible hoses do not have to move any appreciable distance during movement of the rod. Should the rod end be pinned to the frame and the cylinder end with hoses attached be allowed to move, this would not be the case.
Moving hoses are prone to abrasive wear, leaking and pinching in machine features. Also, the slack in the hoses that must be accommodated in the retracted condition would make them prone to being snagged on other machine components and possibly torn out of the ports at either end. In the case of the machine used as an example herein, the travel of the cylinders is 46.5″ from fully retracted to fully extended. In this case, successfully accommodating moving hoses over that length would prove difficult.
Conventional cylinders as described above with a rod extending through one end of the cylinder have forces that are not equal in the extension and retraction directions. The area of the cylinder bore is always greater than the area of the cylinder bore less the cross sectional area of the rod. This is well understood in hydraulic cylinder application and allows the design of the cylinder to be tailored with variation in rod size should the retraction direction not be the primary work direction. A larger rod diameter causes the rod side of the cylinder to have a small area and therefore permits rapid retraction for a given hydraulic pump flow rate. A bursting machine using the concepts disclosed herein uses the more powerful extension direction to pull rod back, and the less powerful direction to thrust rod in the payout direction. The cylinders each have a rod that is large in comparison to the cylinder size, thus there is no compromise on performance of the machine due to either using cylinders in the ‘wrong’ direction, or using cylinders available through an industrial catalog that would have a small rod diameter.
Conventional static bursting machines are configured with the cylinder body stationary and the rod attached to the moving carriage. This carriage serves to grip or propel the rod string in the direction chosen by the operator. According to the invention, the cylinders are configured with the cylinder body attached to the carriage and the rod anchored at the front of the machine where they are loaded against the shoring plate. While the rod size in these cylinders is large in comparison to the cylinder body, it is still smaller than the cylinder body. By reversing the normal orientation, the tooling at the end of the rod string may be pulled into the machine and ‘docked’ between the cylinder rods. This would still be possible in the conventional orientation that has been described, however it should be understood that the machine would require greater overall width. This increased width has the potential to encumber operation and will require additional weight, added pit excavation, and greater difficulty in machine placement should there be other utilities located adjacent to the host pipe being burst.
The combination of the relatively large rod diameter coupled with the desire not to feed the hydraulic cylinders through flexible hoses that move with the bodies creates an opportunity to feed the cylinders through drilled longitudinal passages in the rod. The hydraulic hoses are attached to the rod at the rod end which is anchored to the frame or shore plate. These dual passages are drilled the length of the rod to provide both ingress and egress of the hydraulic fluid to the cylinder cavities. These passages eliminate any need for the hoses to move with the carriage.
Another option according to this aspect the invention that is used in the example below works with the reverse cylinder configuration to narrow the machine further. Offsetting the cylinders such that the cylinders are positioned diagonally relative to the frame of the machine, above and below the spindle shaft will orient the rods so that docked tooling may be removed from between the rods while still allowing the operator to stand close to the center line of the machine. This position close to the center line becomes important when the operator is loading or removing rods manually into/from the docking area along the centerline.
The invention further provides a collapsing rod cradle made to support and align a rod when it is added to or removed from the rod string. The design of this support or cradle becomes complicated when applied to a bursting machine such as that described previously and further having a spindle that applies the pulling or thrusting force via direct threaded attachment to the rod string. The rods are added or removed in a zone that is between the vise and the spindle frame face. Further, during this operation it is necessary for the front end of the rod to reside in the vise, the back half of the rod must sit in a cradle that is in the vicinity of the spindle face. During the cycle of traversing the spindle from right to left, the zone where the rod was added is now ‘compressed’ until the spindle frame nearly touches the vise.
While this right to left spindle frame movement is intended to move the rod string, it also results in the spindle frame occupying the volume where the rod cradle was performing its function of supporting the rod. Once the rod is tied into the rod string by making up the thread between the last and next to last rods, as well as between the last rod and the spindle, the cradle is no longer needed. It would be possible to use a cradle mechanism that collapses into the area below the spindle frame as the frame moves from right to left, and reset into position as the frame moved left to right. Such a design has been used in the past on machines such as the Vermeer PL8000 directional boring machine. In this case, spoil or contamination bound to enter into the machine and fall into the hull would impair the free movement of the device.
For the aforementioned reason, the cradle of the invention is preferably designed in not only a telescoping manner, but is also engineered to follow a path during retraction that would cause it to move away from the rod as it is retracted. This distance gained between the cradle and the rod helps prevent the rod upset from hanging up on the cradle as the relative axial movement occurs. Any entanglement between the cradle and rod could result in a damaged cradle mechanism.
In contrast to the known static pulling machines mentioned above, the machine of the invention uses a front shore plate with a slotted opening to provide good shoring area and limit soil entry into the machine. The shore plate is removed prior to entry of the tooling into the machine through a relatively large (15.5″ diameter) front hole. This is a unique feature when the floating vise is combined with a removable shore plate. These and other aspects of the invention are further described in the detailed description which follows.
BRIEF DESCRIPTION OF THE DRAWINGS
In the accompanying drawings, where like numerals denote like elements:
FIG. 1 is a perspective view of a rod pushing and pulling machine according to the invention;
FIG. 2 is a perspective view of an auxiliary shore plate used with the machine of FIG. 1 ;
FIG. 3 is a perspective view of the spindle assembly, jaw assembly and cylinders of the machine of FIG. 1 , with the cylinders extended and the jaw assembly in its front position;
FIG. 4 is the same view as FIG. 3 , with the cylinders retracted;
FIG. 5 is the same view as FIG. 3 , with the cylinders extended and the jaw assembly in its rear position (the “final docking” position);
FIG. 6 is a perspective view of the jaw assembly of the preceding figures;
FIG. 7 is a top view of the jaw assembly of FIG. 6 ;
FIG. 8 is a side view of the jaw assembly of FIG. 6 ;
FIG. 9 is a front view of the jaw assembly of FIG. 6 ;
FIG. 10 is a top view of the spindle assembly of the preceding figures with cradle extended;
FIG. 11 is a top view of the spindle assembly of the preceding figures with cradle retracted;
FIG. 12 is a side view, in section, taken along the line 12 - 12 in FIG. 10 ;
FIG. 13 is the same view as FIG. 12 , showing the cradle in its retracted position (line 13 - 13 in FIG. 11 );
FIG. 14 is a sectional view taken along the line 14 - 14 in FIG. 10 ;
FIG. 15 is a top view of a thrust cylinder of FIG. 1 , in an extended position;
FIG. 16 is a side view of the thrust cylinder of FIG. 15 ;
FIG. 17 is a sectional view taken along the line 17 - 17 in FIG. 16 ;
FIG. 18 a top view of the rod shown in FIGS. 15-17 ;
FIG. 19 is an enlarged sectional view of the seal carrier shown in FIG. 17 ;
FIG. 20 is an enlarged sectional view of rod seal shown in FIG. 17 ;
FIG. 21 is enlarged side view of the piston and seals of FIG. 18 ;
FIG. 22 is an exploded view of the cradle assembly of the machine of FIG. 1 ;
FIG. 23 is a side view of a rod section used in the invention;
FIG. 24 is a lengthwise sectional view of the rod shown in FIG. 23 ; and
FIGS. 25 and 26 are side and end views, respectively of the load flange of FIG. 14 .
DETAILED DESCRIPTION
FIG. 1 shows a downhole machine 10 of a pipe bursting machine of the invention. A spindle assembly 9 including a spindle frame 12 is shown with its sheet metal cover in place. Spindle frame 12 traverses right-to-left a distance equal to 40% of the overall length of the entire machine. The spindle shaft 115 of spindle assembly 9 is connected to a rod string 11 by a threaded joint in the end of a spindle shaft extension 20 which is made as a separate part for ease of replaceability.
Force to perform the pipe bursting operation is applied to spindle frame 12 via a pair of hydraulic cylinders 26 . A cylinder rod 14 of each cylinder 26 is attached to a front shore plate 25 . Shore plate 25 is placed against the access pit wall and the face of the existing or host pipe. A rod box 31 stores rods to add to or remove from rod string 11 . When rod box 31 is full, tabs 47 are rotated upwards and a lifting hook is engaged. Box 31 is then replaced with a box full of rods or an empty box, as the situation demands. Box 31 sits on a tray 46 . Tray 46 holds box 31 in position to facilitate easy manual rod placement into or away from a rod cradle 18 . A front access door 48 is removed to extract or replace rods. Tray 46 is removable for transport. When tray 46 is removed, the mate to eye 49 is exposed. This pair of eyes 49 facilitate lifting the entire lower unit 10 into or out of the access pit.
Tie down loops 35 are used in transport to secure the lower unit 10 to a truck bed or trailer. A storage box 53 holds the operator's manual. A cover 27 protects a large pilot-controlled hydraulic valve (not shown). This valve facilitates the high hydraulic flows required to actuate the main thrust cylinders 26 . The pilot flows that control the valve are metered at a control station 37 by the machine operator. Direction and flow rate of the main thrust cylinders 26 , as well as spindle motor direction, are controlled at station 37 .
Four height adjustment legs 34 are provided at the four corners of the machine 10 . A hydraulic cylinder 41 of each leg 34 is secured to an outer frame 33 of leg 34 . Frame 33 is bolted to main hull 23 which contains the majority of the working components of the lower unit 10 . Extension of cylinder 41 moves inner leg 45 down, forcing foot 39 against the pit bottom. Foot 39 is free to pivot about a pin 43 . Similar height adjustment legs 34 are located at all four corners of the machine 10 . The cylinders 41 are actuated by the operator at hydraulic control station 29 .
At the front of the unit, shore plate 25 has notches 55 on its upper edge for mounting an auxiliary shore plate 19 thereon ( FIG. 2 ). Auxiliary shore plate 19 doubles up over shore plate 25 with its main face forward. A downwardly opening slot 21 allows the rod string to pass through plate 19 as well as allowing the auxiliary shore plate 19 to be lifted off rod string 11 when nearing completion of the bursting job. This removal becomes necessary so that the tooling may be drawn through the large center hole 28 in shore plate 25 surrounding the rod string 11 . Tabs 24 , located on both sides of plate 19 , fit into notches 55 to assure alignment and proper height of slot 21 . A series of slots 22 near the upper edge of plate 19 allow it to be lowered into or raised out of the pit.
FIG. 3 is an isometric view from the same vantage as FIG. 1 , however it differs in that all external components of machine 10 have been removed. Spindle frame 12 is supported vertically by track rollers 17 . Two track rollers 17 are visible; they in fact exist at all four corners of the frame 12 . Track rollers 17 may be those available from Torrington Manufacturing, effectively small steel wheels with an internal needle roller bearing. In this view, cylinder body 16 is visible throughout its length. Rod cradle 18 is shown fully extended with a crotch 30 aligned with shaft extension 20 . Cylinder rod 14 is also fully extended, making the area for rod placement and removal of rods between shaft extension 20 and rod string 11 easy to see.
A vise assembly 15 is shown with rod string 11 clamped in one of two jaw sets 72 , 73 . Serrations 51 on jaws 72 , 73 can clamp on an added rod to apply torque. Vise 15 is further guided and restrained by cylinder rods 14 which pass through cylindrical sleeves 63 forming ends of the frame 36 supporting vise 15 for movement along cylinder rods 14 . Shoulders 13 at the front ends of cylinder rods 14 are mounted to and react in thrust against shore plate 25 . Hydraulic ports 57 and 61 on each rod 14 are used to connect flexible hydraulic supply hoses to feed the thrust cylinders 26 made up of rod 14 and cylinder body 16 . Hydraulic control valve 59 sequences the operation of the jaws in vise 15 .
FIG. 4 is the same set of components as FIG. 3 , however rods 14 have been fully retracted into cylinder bodies 16 . With shoulders 13 attached to shore plate 25 (such as by bolts) and the shore plate 25 further bolted to hull 23 , the result of retracting rod 14 is actually to move cylinder bodies 16 and attached spindle frame 12 closer to shore plate 25 . In this position, vise 15 is very close to spindle frame 12 , leaving no room for rod cradle 18 . Rod cradle 18 , partially visible behind vise 15 , has retracted into spindle frame 12 with its supporting arms 101 inside spindle frame 12 and crosspiece 102 against the spindle frame 12 . Rod string 11 is now in position to be threaded to spindle extension 20 . This is accomplished by clamping the forward set of jaws 72 in vise 15 against rod string 11 (operation shown completed) and rotating the spindle extension 20 in the appropriate direction.
Referring to FIG. 5 , rod 14 is then fully extended from cylinder body 16 . Vise 15 is pulled along with spindle frame 12 from its normal working position. This is accomplished by engaging jaw set 72 against rod string 11 and extending rod 14 to move the entire assembly of frame 12 and vise 15 to the right. This position is desirable when tooling must be pulled into hull 23 for final docking as explained hereafter. Vise 15 is more completely visible in FIG. 6 . Sleeves 63 are hollow, permitting them to be centered on rods 14 . This provides torque reaction when the rod string is tightened, as well as permitting sliding along rods 14 when room must be made for docking of the tooling as per FIG. 5 .
Front faces 67 of vise frame 36 are configured to rest against the back of shore plate 25 . In doing so, they react against residual elastic pipe forces that may be present. Idler rollers 69 set on spaced vertical axles 70 keep rod string 11 centered relative to the vise and therefore to the rest of the machine. Rollers 69 are engineered so that shoulders on the rod will pass freely through them. A pair of cylinders 71 actuate clamping of jaws 72 and 73 . Another cylinder 65 , while the same size as cylinder 71 , is positioned to rotate jaws 73 about the axis of rod string 11 . This is done when jaws 73 are clamped and serrated surfaces 51 of jaws 73 grip the rod securely. Cylinder 65 breaks loose the threaded joint between rod string 11 and the endmost rod, allowing the endmost rod to be removed from the string. To loosen the threaded joint between rod string 11 and the endmost joint, jaws 73 turn approximately 30°, in any case less than 360°. This feature is only used to loosen threaded rod joints, never to tighten, because jaws 73 create very high torque relative to the spindle rotation drive motor.
FIG. 7 shows all of the jaws 72 and 73 from above. In this figure, jaws 72 are clamped on the available rod, while jaws 73 are open. In FIG. 8 , a greater portion of cylinder 65 is exposed. In FIG. 9 , idler rollers 69 are fully visible in profile, shown guiding and centering rod string 11 . This view demonstrates how cylinder 71 is positioned to provide clamp load on rod string 11 .
In FIG. 10 , rod cradle 18 is shown fully extended. The four track rollers 17 are mounted at respective corners of rectangular spindle frame 12 , and a grease zerk manifold 139 is exposed through an opening in the top of frame 12 . Frame 12 includes a pair of front and rear walls 141 , 142 having pairs of aligned openings 143 , 144 therein in which cylinder bodies 16 are mounted, as well as internal structural members 146 on which various spindle assembly components are mounted as shown in FIG. 14 . Openings 143 , 144 preferably open laterally so that cylinders 26 can be removably mounted therein. Pairs of generally C-shaped holders 147 , 148 are placed over the outside of cylinder body 16 and bolted to frame 12 to hold cylinders 26 in place. To hold cylinder bodies 16 stationary relative to frame 12 , openings 143 and front holder 147 engage an annular groove 77 on the outside of cylinder body 16 , discussed further in connection with FIGS. 15-17 below.
As shown in FIG. 12 , an arm 101 is configured to slide freely through a concentrically positioned center hole in bushing 103 . A collar 105 fixed to the outside of arm 101 limits outward travel of cradle 18 by bumping against the inner face of bushing 103 . A piston 107 provides the reaction force needed to hold cradle 18 in the proper position. Piston 107 is secured near the rear end of arm 101 behind collar 105 and slides freely within a tube 113 . Piston 107 is not located concentrically on arm 101 . In this manner, the angle between the axis of arm 101 and the axis of tube 113 will vary as cradle 18 is moved away back and forth through its range of travel, urged to extend by a gas spring 112 which is attached at one end to the inside of tubular arm 101 at the position of collar 105 . Cap 109 seals tube 113 at its rear end, and optional oiler 111 provides drip lubrication to the interior of tube 113 .
The change in angle causes cradle 18 to fall away from the bottom of the rod as arms 101 of cradle 18 are retracted into their respective tubes 113 . As shown in FIGS. 12 and 13 , piston 107 biases the rear end of arm 101 downwardly relative to the opening through bushing 103 , causing the front end to which cradle 18 is attached to be lifted upwardly. This displacement lessens as the distance between piston 107 and bushing 103 becomes greater, causing cradle 18 to drop downwardly a slight distance as piston reaches the position shown in FIG. 13 . In this position, the angle between the axis of arm 101 and axis of tube 103 is smaller that as shown in FIG. 12 .
Referring to FIG. 14 , a front end portion of the spindle shaft 115 is mounted in a front plain bearing 119 . Bearing 119 is contained in a bearing housing 121 that is bolted to the front face of spindle frame 12 . Bearing 119 is designed only for handling radial forces transmitted from shaft 115 . A rear end portion of spindle shaft 115 is supported by a set of tapered roller bearings 127 located in a housing 123 that is also bolted to spindle frame 12 . Tapered roller bearings 127 support shaft 115 in both thrust and pullback directions. However, bearings 127 are sized only to handle the magnitude of thrust developed by the machine in payout, in this example about 40,000 lb. During pullback, the capacity of bearings 127 would be greatly exceeded by the 250,000 lb. of pullback force that can be produced by the main thrust cylinders 26 . For this reason, the system has been designed to allow the shaft 115 to float, unloading the tapered roller bearings 127 in the pullback direction.
Spring can 131 is loaded against taper roller bearings 127 by a coil spring 129 for small magnitudes of pullback, such as breaking or unthreading the rod joint. When the load increases above a threshold level such as 1000 lb, the spring 131 has compressed far enough that a flange 117 mounted on shaft 115 at an intermediate position along its length contacts the face of a load flange 125 . As shown in FIGS. 25 and 26 , load flange 125 is preferably in the form of a wedge with its wide end bolted to and braced against frame 12 . The narrow end of load flange 125 has a cylindrical cutaway 126 to provide clearance for the spindle shaft 115 , and a counterbore the bottom of which forms a load bearing surface 128 . When flange 117 is in substantial contact with surface 128 of flange 125 , shaft 115 will not rotate due to the high friction induced. This is desired in that the machine is intended for static pipe bursting or other non-rotating pullback operations. Use of the plain bearing 119 and load flange 125 with flange 117 avoids the size and expense of a tapered roller bearing capable of handling 250,000 lb.
A sprocket 133 is torsionally keyed to shaft 115 . A roller chain (not shown) drives sprocket 133 under the operator's control to thread or unthread rods or turn small diameter tooling during payout. A water swivel 137 allows drilling fluids to pass to the hollow drill stem while being fed by a non-rotating hose. Locknuts 135 are used to secure sprocket 133 to shaft 115 in the axial direction.
FIGS. 15-21 show the structure of cylinders 26 in detail. Hydraulic port 57 at the distal end of rod 14 communicates with a flow passage 97 inside rod 14 which opens onto the piston side of rod 14 . Connecting the hydraulic fluid pressure source to port 57 while connecting port 61 to tank fills cylinder body 16 with fluid and extends rod 14 . Port 61 communicates with another lengthwise flow passage 99 which extends almost to the rear end of rod 14 . Passage 99 communicates with an outwardly opening annular groove 94 through a radial port 87 . Fluid in groove 94 enters the space on the rod side of a piston 90 mounted at the rear end of rod 14 through a series of cutaways 89 in piston 90 , retracting rod 14 when port 57 is connected to tank.
Piston 90 is mounted on the end of rod 14 by a steel lock ring 95 . A split nylon wear ring 93 mounted in an annular groove on the outside of piston 90 slides along the inside of cylinder 16 . Leakage between piston side and rod side is prevented by a urethane umbrella-type seal 96 mounted in another groove frontwardly from wear ring 93 . A seal carrier or cap 75 is secured by threads 83 to the front end of cylinder body 16 . Cap is supported on rod 14 by a nylon split bearing ring 81 and leakage is prevented by a series of nylon seals 82 . As discussed above, rod 14 has a large diameter relative to cylinder body 16 , making the annular space 88 on the rod side thin, so that only a small flow of fluid is required retract the cylinder in FIGS. 15-17 . For this purpose, the cross section area of annular space 88 is from about 10% to 60% of the cross sectional area of the cylinder cavity. (This equates to a ratio of working surface area of from 10:1 to 1.67:1.) If annular space 88 is excessively thin (<10% of the cross sectional area of the cylinder cavity), retraction of the cylinder will not be powerful enough. On the other hand, when it is too wide (exceeds 60% of the cross sectional area of the cylinder cavity) the cylinder begins to behave like a conventional hydraulic cylinder.
FIGS. 23 and 24 show a preferred form of drill rod 100 of the type used to make rod string 11 . Multiple rods 100 are joined together end-to-end to create a string 11 as long as 500 feet or more. Male thread 116 mates into the next rod's female thread 122 . An undercut 118 is provided for jaws 72 to grip. Should the axial load be high, the rod 100 may slip until a shoulder 120 contacts jaw 72 . Jaws 73 engage the outer surface of each rod 100 outside of female thread 122 . An axial bore 124 of rod 100 is optionally used conduct fluid from the downhole machine to the front of the rod string. Bore 124 also reduces the weight of rods 100 to facilitate manual handling.
Operation of downhole machine 10 according to the invention is as follows. A typical job will involve pushing a rod string out through an existing pipeline from the exit pit (where machine 10 is) to the entry opening in the pipeline, such as in a trench or manhole. To extend a rod string 11 , the machine 10 starts in the position shown in FIG. 3 , but with no rod string 11 present. A rod 100 is removed from box 31 and placed in cradle 18 at crotch 30 with the male threaded end 116 facing shaft extension 20 , which has a female thread ( FIG. 14 ). The female end 122 is placed in rear jaws 73 , and jaws 73 are closed on it. The spindle assembly 12 is then operated to thread shaft extension 20 over male end 116 . Once this is done, jaws 73 are opened and spindle frame 12 is moved to the left by retraction of cylinders 26 to assume the position shown in FIG. 4 . Jaws 72 are then operated to grip rod 100 at undercut 118 . The spindle shaft 115 and extension 20 are then rotated in reverse to unthread extension 20 from male end 116 . Cylinders 26 are then extended to move spindle frame 12 to the right to assume the position shown in FIG. 3 , and the machine 10 is ready to accept another rod 100 .
The procedure for adding the second and subsequent rods 100 is the same as described above, except that jaws 73 are not closed on the female end 122 of the new rod 100 , and the male end 116 of the previous rod is positioned between jaws 73 as shown in FIG. 3 . Instead, the female end of rod 122 is brought over male end 116 of the previous rod held in jaws 72 . When spindle assembly 12 is then operated to thread shaft extension 20 over male end 116 of the new rod, female end 122 of the new rod is threaded onto male end 116 of the previous rod at the same time. In the process of retracting the cylinders 26 to assume the position of FIG. 4 , the entire rod string 11 is pushed forward. This process is repeated until the leading end of string 11 emerges from the entry opening.
Once the push out operation is complete, a bursting head or other tooling is mounted on the distal end of rod string 11 in preparation for pullback through the existing hole or pipeline. Such a bursting head preferably also pulls in a replacement pipe at the same time in a manner well known in the art.
Pullback starts with visel 5 closed on neck or undercut 118 as shown in FIG. 4 . Jaws 72 are opened, and cylinders 26 are extended to move spindle frame 12 to the right, pulling the rod string 11 and bursting head with it. Once spindle frame 12 has reached the position shown in FIG. 3 , jaws 72 are closed on the neck 118 of the second to last rod 100 , and jaws 73 are actuated by an automatic cycle that clamps female end 122 of the last rod 100 and rotates it a sufficient distance under the action of cylinder 65 to loosen the threaded joint; one-eighth to one-quarter turn is generally enough for this purpose. Jaws 73 are then opened and returned to their non-rotated position. Spindle shaft 115 is then rotated to unthread the last rod 100 the rest of the way from the second to last rod, with spindle frame 12 moving about an inch to the right during this process. Jaws 73 are then closed again on last rod 100 , and spindle assembly 9 is operated to unthread last rod 100 from shaft extension 20 . When this is done, jaws 73 are opened, and the last rod 100 may be manually removed and placed in storage box 31 . Rods 100 are sized to be lifted and handled by one person; in this embodiment, rods 100 weigh 52 pounds each.
The pullback steps are then repeated as required until the first rod 100 , having the bursting head attached thereto, is encountered. At this time, outer shore plate 19 is removed by attaching chains with hooks to openings 22 , exposing center hole 28 . Last rod 100 is then removed in a normal manner, resulting in a leading end portion 91 of bursting head 92 held in jaws 72 . Shaft extension 20 is then threaded onto bursting head 92 , and jaws 72 remain closed. Cylinders 26 are then extended, pulling back bursting head 92 through hole 28 into the position shown in FIG. 5 . Vise assembly 15 travels back as well because it is locked to bursting head 92 by jaws 72 . Bursting head 92 is then unthreaded from shaft extension 20 and jaws 72 are opened, allowing bursting head 92 to be lifted out of the pit.
In the foregoing manner, the machine 10 of the invention can be used for pipe bursting and replacement. During the pushing out step, it may often be desirable to mount a drill bit on the leading end of the drill string in order drill a pilot bore through the ground, if there is no existing pipeline to follow. The drill bit may of the type having an angled steering face and can be steered with machine 12 using the well known push-to-steer, push-and-spin to bore straight ahead method. The drill bit might also be needed to drill through collapsed or block portions of an existing pipeline to be replaced. The machine of these invention is capable of performing these functions as well as pull back under much higher loads, without need for expensive high capacity roller bearings.
While certain embodiments of the invention have been illustrated for the purposes of this disclosure, numerous changes in the method and apparatus of the invention presented herein may be made by those skilled in the art, such changes being embodied within the scope and spirit of the present invention as defined in the appended claims. For example, while the invention has been discussed as a static bursting system, it is also possible to use a bursting or pipe splitting head capable of deliver cyclic impacts to the pipeline being burst. | A rod pushing and pulling machine includes at least one hydraulic cylinder having a front end thereof engagable with a reaction surface at an entry opening of a existing pipeline or borehole, a spindle assembly, and a dual vise assembly. The spindle assembly includes a frame, a spindle shaft rotatably mounted in the frame, a distal end of the spindle shaft being threaded for engagement with a mating thread of a rod, a drive system for rotating the spindle shaft in threading and unthreading directions, the spindle frame being secured to a rear end of the hydraulic cylinder for pushing or pulling of a rod string engaged to the spindle shaft upon extension or retraction of the hydraulic cylinder, and a support assembly for the spindle shaft. The support assembly includes a set of roller bearings rotatably supporting the spindle shaft, a radial flange on the spindle shaft, and a load flange secured to the spindle frame positioned to engage the radial flange, whereby the radial flange comes into engagement with the load flange during pulling operation to prevent rotation of the spindle shaft during pulling operation, and leaves engagement with the load flange during pushing operation so that the spindle shaft may rotate during pushing operation supported by the roller bearings. The dual vise assembly has two pairs of separately actuable jaws positioned to grip a rod nearest the spindle shaft and a rod adjacent the rod nearest the spindle shaft. | 4 |
This case claims benefit under 35 U.S.C. § 119 of German priority document 19734438.0 filed on Aug. 8, 1997. This document, as well as German priority document 19756093.8, filed Dec. 17, 1997, are hereby incorporated by reference.
DETAILED DESCRIPTION OF THE INVENTION
The invention relates to a novel readily soluble crystal modification (hereafter referred to as "the first crystal modification") of the compound of formula I ##STR2## in which the transmission X-ray diffraction pattern obtained with a focusing Debye-Scherrer beam and Cu-K.sub.α1 -radiation, has lines at the following diffraction angles 2θ:
Lines of strong intensity: 10.65; 14.20; 14.80; 16.10; 21.70; 23.15; 24.40; 24.85; 25.50; 25.85; 26.90; and 29.85 degrees,
Lines of medium intensity: 7.40; 9.80; 13.10; 15.45; 16.80; 20.70; 21.45; 22.80; 23.85; 27.25; and 28.95 degrees,
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is the X-ray diffraction pattern of the first crystal modification.
FIG. 2 is the X-ray diffraction pattern of the second crystal modification.
FIG. 3 is the infrared spectrum of the first crystal modification.
The X-ray diffraction pattern of the first crystal modification recorded using Cu-K.sub.α1 radiation is shown in FIG. 1. The pattern was recorded using the STADI P two-circle diffractometer from Stoe (Darmstadt, Germany) and the computer-assisted single crystal diffractometer R3 mN from Siemens (radiation used: MoK.sub.α).
The infrared spectrum of the first crystal modification of the compound of formula I(1 mg in 300 mg of KBr) recorded using an infrared spectrophotometer shows the following main bands (units: cm -1 ):
______________________________________1321 1481 672 3201 1607 3355 763 701 1109 1264 908 948 1065 1384 754 511 1536 1361 592 733 1663 852 427 960 1241 1014 3111 1779 1410 3297 3065 1811 1160 877 3221 484 1691 940 974 3442 831 3274 3129 3434 1188 894 628______________________________________
The stated wavenumbers are arranged in ascending intensity. The infrared spectrum of the first crystal modification of the compound of formula I according to Example 1 is shown in FIG. 3, the transmittance in % being stated along the ordinate and the wavenumber in cm -1 along the abscissa.
The compound of formula I crystallizes in the first crystal modification in the space group P2 1 /c with 8 molecules in the unit cell. Molecules of the compound of formula I are present as dimers which originate from the individual molecules by formation of a -C═O . . . HN hydrogen bridge bond (2.938 Å), the two molecular levels being virtually perpendicular to one another (91.2°). The two molecules have very different conformations. The angles made by the five- and six-membered rings with the central carbonyl group are 5.4° and 2.1° and 23.4° and 23.1°, respectively. The latter twist creates the steric preconditions permitting the hydrogen bridge bond between the two molecules.
The compound of formula I is known per se and is also referred to as Leflunomide (HWA 486). It can be obtained in the manner described in U.S. Pat. No. 4,284,786. However, the crystals prepared by recrystallization from, for example, toluene are obtained in a crystal form called the second crystal modification. The X-ray diffraction pattern (Cu-K.sub.α1 radiation) of the second crystal modification is shown in FIG. 2 and has characteristic lines at the following diffraction angles 2θ:
Lines of strong intensity: 16.70; 18.90; 23.00; 23.65; and 29.05 degrees.
Lines of medium intensity: 8.35; 12.65; 15.00; 15.30; 18.35; 21.25; 22.15; 24.10; 24.65; 25.45; 26.65; 27.40; 28.00; and 28.30 degrees.
The compound of formula I crystallizes in the second crystal modification in the space group P2 1 /c with 4 molecules in the unit cell. The molecule is essentially planar. The angle between the planar groups of atoms is less than 2.4°. The molecules are arranged in stacks in the crystal. The molecules lie in stacks adjacent to one another and are arranged in an antiparallel manner. Very weak hydrogen bridge bonds link the dimers in the crystal (NH . . . N: 3.1444 Å). The C═O group is not involved in any hydrogen bridge bonding.
The X-ray diffraction patterns furthermore permit the determination of the amount of the first crystal modification in a mixture containing both modifications. The line at 2θ=8.35° of the second crystal modification and the line at 2θ=16.1° of the first crystal modification are suitable for the quantitative determination. If the ratio of the peak heights is calculated and is correlated with the content of the modification, a calibration line is obtained. The limit of detection of this method is about 0.3% of the first crystal modification in crystals containing the second crystal modification.
The first crystal modification has better water solubility than the second crystal modification. At 37° C., 38 mg/l of the first crystal modification can be dissolved whereas 25 mg/I of the second crystal modification go into solution. Furthermore, the first crystal modification is stable in the temperature range from -15° C. to +40° C., preferably from 20° C. to 40° C., and is not converted into the second crystal modification under these conditions.
The first crystal modification, according to the invention, of the compound of formula I is obtained, for example, by heating a suspension of crystals of the second crystal modification or mixtures of the second crystal modification and the first crystal modification of the compound of formula I in a solvent to a temperature of from about 10° C. to about 40° C., preferably from about 15° C. to about 30° C., in particular from about 20° C. to about 25° C. The preparation rate is essentially dependent on the temperature. Solvents in which the compound of formula I are poorly soluble are advantageously used. For example, it is possible to use water or aqueous solutions containing (C 1 -C 4 ) alcohols (e.g., methanol, ethanol, propanol, isopropanol, butanol or isobutanol) and/or ketones, such as acetone or methyl ethyl ketone, or mixtures thereof. As a rule, the heating is carried out in aqueous suspension, expediently while stirring or shaking. The heat treatment is carried out until through this process the second crystal modification is completely converted into the first crystal modification.
The complete conversion of the second crystal modification to the first crystal modification is dependent on the temperature and, as a rule, takes from 36 hours to 65 hours, preferably from 48 hours to 60 hours, at a temperature of 20° C. The reaction is monitored by X-ray diffraction or IR spectroscopy by means of samples taken during the treatment.
A further process for the preparation of the first crystal modification of the compound of formula I comprises dissolving the second crystal modification or mixtures of the first and second crystal modifications in a solvent and then cooling the solution abruptly to temperatures of from about -5° C. to about -25° C. The terms "solution" and "suspension" are used interchangeably throughout and are meant to include circumstances where a solid or solids is placed in a solvent or a mixture of solvents regardless of solubility. Suitable solvents are, for example, water-miscible solvents such as (C 1 -C 4 ) alcohols, as well as ketones, such as acetone or methyl ethyl ketone, or other solvents, such as ethyl acetate, toluene dichloromethane or mixtures thereof. The dissolution process takes place at room temperature of from about 20° C. to about 25° C. or at elevated temperatures up to the boiling point of the solvent under atmospheric pressure or under superatmospheric or reduced pressure. The solution obtained is, if required, filtered in order to separate off undissolved components or crystals from Leflunomide. The filtered solution is then cooled so rapidly that only crystals of the first crystal modification form. An adequate cooling process comprises, for example, introducing the filtered solution into a vessel which has been cooled to -15° C. or spraying filtered solution into a space cooled to -10° C. or cooling the solution under vacuum condensation conditions.
The preferred process comprises introducing the compound of formula I into methanol and carrying out the dissolution process at the boiling point of methanol at atmospheric pressure or reduced pressure, then filtering the hot solution and transferring the filtered solution to a vessel which has been cooled to -15° C., the transfer being effected so slowly that the temperature of the crystal suspension obtained does not increase to more than -10° C. The precipitated crystals are then washed several times with methanol and are dried under reduced pressure.
The crystallization can be carried out without seeding with crystals of the first crystal modification; however seeding with crystals of the first crystal modification is the preferred method. The seeding is effected in the cooled vessel. The amount of seed material depends on the amount of the solution and can be easily determined by a person of ordinary skill in the art. The aforementioned processes are also suitable for converting mixtures containing the first and second crystal modifications into an essentially pure the first crystal modification of the compound of formula I.
The invention also relates to novel processes for the preparation of the second crystal modification of formula I. By means of novel processes, it is also possible to convert mixtures containing the first and second crystal modifications specifically into the second crystal modification. For this purpose, for example, crystals of the first crystal modification, or mixtures of the first and second crystal modifications are dissolved in a solvent. Suitable solvents are, for example, water-miscible solvents such as C 1 -C 4 alcohols (e.g., methanol, ethanol, propanol, isopropanol, butanol or isobutanol), as well as ketones such as acetone or methyl ethyl ketone, or mixtures thereof. Mixtures of organic solvents with water, for example of about 40% to about 90% of isopropanol, have also proven useful.
The dissolution process is preferably carried out at elevated temperature up to the boiling point of the respective solvent. The hot solution is kept at the boiling point for some time in order to ensure complete dissolution of the compound of formula I. The filtered solution is then cooled so slowly that only crystals of the second crystal modification form. Cooling is preferably effected to final temperatures of about 20° C. to about -10° C., in particular to temperatures of about 10° C. to about -5° C., very particularly preferably to temperatures of from about 10° C. to about 5° C. The crystals are separated off and washed with isopropanol and then with water. The substance is dried at elevated temperature, preferably at about 60° C. under reduced pressure or at atmospheric pressure.
A preferred process for preparing the second crystal modification comprises dissolving the compound of formula I in an about 80% strength isopropanol at the boiling point of isopropanol and at atmospheric pressure or under reduced pressure and then cooling the hot solution so slowly that the crystallization takes place at temperatures of more than about 40° C., preferably from about 40° C. to about 85° C., particularly preferably from about 45° C. to about 80° C., in particular from about 50° C. to about 70° C. The precipitated crystals are then washed several times with isopropanol and are dried under reduced pressure. The crystallization can be carried out without seeding with crystals of the second crystal modification or preferably in the presence of crystals of the second crystal modification, which are introduced by seeding into the solution containing the compound of formula I. Seeding may also be carried out several times at different temperatures. The amount of the seed material depends on the amount of the solution and can be readily determined by a person of ordinary skill in the art.
A particularly preferred process for the preparation of the compound of formula I in the second crystal modification comprises
a) transferring the compound of formula I where no the second crystal modification is present or mixtures of the second crystal modification and other crystal forms of the compound of formula I into an organic solvent or into mixtures of organic solvents and water,
b) heating the mixture obtained to a temperature greater than about 40° C. to about the boiling point of the organic solvent,
c) diluting the resulting solution with water or distilling off organic solvent so that the organic solvent and the water are present in a ratio of from 4:1 to 0.3:1 and
d) carrying out the crystallization at temperatures above about 40° C. (The solution obtained is preferably filtered after process step b).
By means of the particularly preferred process, it is also possible to convert mixtures containing the first and second crystal modifications specifically into the second crystal modification. For this purpose, crystals of the first crystal modification or mixtures of the first and second crystal modifications are dissolved in a mixture containing organic solvents and water. Suitable solvents are, for example, water-miscible solvents such as C 1 -C 4 alcohols (e.g., methanol, ethanol, propanol, isopropanol, butanol or isobutanol), as well as ketones such as acetone or methyl ethyl ketone, or mixtures thereof.
Advantageous mixtures contain organic solvent and water in a ratio of from about 1:1 to about 8:1, preferably from about 2:1 to about 6:1, and in particular from about 3:1 to about 5:1.
The preparation of the solution is preferably carried out at elevated temperature, in particular at temperatures of from about 41° C. to the boiling point of the respective organic solvent. The heated solution is, for example, kept for some time at the boiling point in order to ensure complete dissolution of the compound of formula I. The dissolution process can also be carried out at superatmospheric pressure. The solution is then filtered. The filter used has a pore diameter of from about 0.1 μm to about 200 μm. Advantageously, water which has the same temperature as the filtered solution is then added to the filtered solution, or the organic solvent is distilled off. The solutions obtained advantageously contain the organic solvent and water in a ratio of from about 4:1 to about 0.3:1, preferably from about 2:1 to about 0.6:1, particularly preferably from about 1.6:1 to about 0.8:1. Cooling is then carried out slowly to a minimum temperature of about 40° C. and crystals form. The crystals are separated off and are washed with isopropanol and then with water and, advantageously, dried at elevated temperature, preferably at about 60° C., under reduced pressure or at atmospheric pressure.
A particularly preferred process comprises dissolving the compound of formula I in a mixture of isopropanol and water in a ratio of from about 4:1 to about 5:1 and at the boiling point of isopropanol under atmospheric pressure or reduced pressure and filtering the solution preferably, a filter pore of lumen diameter is used. Thereafter, water at the same temperature is added to the hot solution in an amount such that a ratio of isopropanol to water is from about 2:1 to about 0.8:1. The crystallization is then carried out at temperatures of more than about 40° C., preferably from about 40° C. to about 85° C., particularly preferably from about 45° C. to about 80° C., in particular from about 50° C. to about 70° C. The crystals are then washed several times with isopropanol and are dried under reduced pressure.
A further process for the preparation of the second crystal modification from the first crystal modification or from a mixture containing the first and second crystal modifications comprises heating the solid forms to a temperature of from above about 40° C. to about 130° C., preferably from about 50° C. to about 110° C., in particular from about 70° C. to about 105° C., very particularly preferably about 100° C. The conversion of the first crystal modification into 1 is dependent on the temperature and, for example at about 100° C., takes from 2 to 5 hours, preferably from 2 to 3 hours.
A further process for the preparation of the second crystal modification comprises preparing a suspension containing crystals of the first crystal modification or a mixture of crystals containing the first and second crystal modifications and a solvent.
The second crystal modification of the compound of formula I is obtained by heating the suspension of the crystals in a solvent to a temperature of more than about 40° C., preferably from about 41° C. to about 100° C., in particular from about 50° C. to about 70° C. The preparation is essentially dependent on temperature. Advantageous solvents are those in which the compound of formula I has poor solubility. For example, it is possible to use water or aqueous solutions containing C 1 -C 4 alcohols, ketones, such as methyl ethyl ketone or acetone, or a mixture thereof. As a rule, the heating is effected in an aqueous suspension, expediently while stirring or shaking. The heat treatment is carried out until the first crystal modification has been significantly converted into the second crystal modification.
The conversion of the first crystal modification into the second crystal modification is dependent on the temperature and, as a rule, takes from 20 hours to 28 hours, preferably 24 hours, at a temperature of 50° C. The reaction is monitored by X-ray diffraction or IR spectroscopy by means of samples taken during the treatment.
The first crystal modification, according to the invention, of the compound of formula I is suitable, for example, for the treatment of
acute immunological episodes, such as sepsis, allergies, graft-versus-host- and host-versus-graft-reactions
autoimmune diseases, in particular rheumatoid arthritis, systemic lupus erythematosus, multiple sclerosis
psoriasis, atopic dermatitis, asthma, urticaria, rhinitis, uveitis type II diabetes
liver fibrosis, cystic fibrosis, colitis
cancers, such as lung cancer, leukemia, ovarian cancer, sarcomas, Kaposi's sarcoma, meningioma, intestinal cancer, lymphatic cancer, brain tumors, breast cancer, pancreatic cancer, prostate cancer or skin cancer.
The invention also relates to drugs comprising an effective content of the first crystal modification of the compound of formula I together with a pharmaceutical excipient, additive and/or additional active ingredients and adjuvants.
The drugs according to the invention, comprising an effective content of the first crystal modification of the compound of formula I, have the same efficacy in humans who suffer from rheumatic arthritis in comparison with the treatment with a drug comprising an effective content of the second crystal modification of the compound of formula I.
The invention furthermore relates to a process for the preparation of the drug, which comprises processing the first crystal modification of the compound of formula I and a pharmaceutical excipient to give a pharmaceutical dosage form.
The drug according to the invention may be present as a dosage unit in dosage forms such as capsules (including microcapsules), tablets (including sugar-coated tablets, pills) or suppositories, the capsule material performing the function of the excipient where capsules are used and it being possible for the content to be present, for example, as a powder, gel, emulsion, dispersion or suspension. However, it is particularly advantageous and simple to prepare oral (peroral) formulations containing the first crystal modification of the compound of formula I, which contain the calculated amount of the active ingredient together with a pharmaceutical excipient. An appropriate formulation (suppository) for rectal therapy may also be used. Transdermal application in the form of ointments or creams or oral administration of tablets or suspensions which contain the formulation according to the invention is also possible.
In addition to the active ingredients, ointments, pastes, creams, and powders may contain conventional excipients, for example, animal and vegetable fats, waxes, paraffins, starch, tragacanth, cellulose derivatives, polyethylene glycols, silicones, bentonites, talc, zinc oxide, lactose, silica, aluminum hydroxide, calcium silicate, polyamide powder, or a mixture of these substances.
The tablets, pills or granules can be prepared by conventional processes, such as compression, immersion, or fluidized-bed processes, or by coating in a pan, and contain excipients and other conventional adjuvants, such as gelatine, agarose, starch (for example potato, corn or wheat starch) cellulose, such as ethyl cellulose, silica, various sugars, such as lactose, magnesium carbonate and/or calcium phosphates. The sugar-coating solution usually comprises sugar and/or starch syrup and generally also contains gelatine, gum Arabic, polyvinylpyrrolidone, synthetic cellulose esters, surfactants, plasticizers, pigments, and similar additives according to the prior art. Any conventional flow regulators, lubricants, such as magnesium stearate, and external lubricants may be used for the preparation of the formulations.
The dosage to be used is of course dependent on various factors, such as the host be treated (i.e., human or animal), age, weight, general state of health, the severity of the symptoms, the disease to be treated, the type of accompanying treatment with other drugs, or the frequency of the treatment. The doses are administered in general several times per day and preferably once to three times per day.
A suitable therapy therefore comprises, for example, administering one, two or 3 single doses of a formulation containing N-(4-trifluoromethylphenyl)-5-methylisoxazole-4-carboxamide in The first crystal modification in an amount of from 2 to 150 mg, preferably from 10 to 100 mg, in particular from 10 to 50 mg.
The amount of the active ingredients does of course depend on the number of single doses and also on the disease to be treated. The single dose may also comprise a plurality of simultaneously administered dosage units.
EXAMPLE 1
Preparation of The first crystal modification
About 40 mg of the compound of formula I, prepared according to U.S. Pat. No. 4,284,786, were shaken with 40 ml of water in bottles (volume 45 ml). The shaking of the closed bottles was carried out at 15° C.-25° C. in a water bath. After 48 hours, a sample was taken, filtered and dried and a powder X-ray diffraction pattern was prepared. The measurement was carried out using the STADI P two-circle diffractometer from Stoe (Darmstadt, Germany) with Cu-K.sub.α1 radiation by the Debye-Scherrer method under transmission conditions.
FIG. 1 shows the resulting X-ray diffraction pattern and is typical of the first crystal modification of the compound of formula I.
EXAMPLE 2
Solubility in water
______________________________________Apparatus flask, magnetic stirrer, water bath 37° C. ± 0.5° C. Medium water (+37° C.) Sampling 5 hours Preparation First and second crystal modifications according to Examples 1 and 2 were transferred to water and stirred vigorously at 37° C. Detection UV spectroscopy at a wavelength of 258 μm Result: Second crystal modification 25 mg dissolved in 1 liter of water at 37° C. First crystal modification 38 mg dissolved in 1 liter of water at 37° C.______________________________________
EXAMPLE 3
Stability of the first crystal modification
Samples of The first crystal modification were prepared as in Example 1 and were stored at various temperatures at atmospheric humidity. After the stated times, samples were taken and an X-ray diffraction pattern was prepared as in Example 1. Table 1 shows the results.
TABLE 1______________________________________Time (Months) Storage conditions Crystal modification______________________________________1 -15° C. First 3 -15° C. First 6 -15° C. First 1 +25° C. First 3 +25° C. First 6 +25° C. First 1 +40° C. First 3 +40° C. First 6 +40° C. First 1 +40° C./75% relative humidity First 3 +40° C./75% relative humidity First 6 +40° C./75% relative humidity First 1 +60° C. about 76% Second 3 +60° C. Second______________________________________ .sup.1) A calibration curve was used for the determination of the second crystal modification.
For preparing the calibration curve for the quantitative determination, the reflection at 2θ=8.35° was used for phase 1 and the reflection at 2θ=16.1° was used for phase 2. The ratios of the corresponding peak heights were calculated and were correlated with the contents of phase 2. The limit of the method is 0.3%. The sample after storage for 1 month at 60° C. contains about 76% of the second crystal modification according to this method.
EXAMPLE 4
Preparation of The second crystal modification
Water-moist crude Leflunomide is first dissolved in isopropanol/water (corresponding to 16 kg of crude, dry Leflunomide in 28 l of isopropanol plus the amount of water which, together with the water content of the moist product, gives a total amount of water of 9 l).
The mixture is then heated to 78° C. to 82° C., stirred at this temperature for 25 minutes (min) and then filtered through a pressure funnel into a vessel also already heated to the same temperature. The pressure filter is rinsed with an amount of isopropanol which, together with isopropanol used (iPrOH), gives an iPrOH/water ratio of 4:1 (in this case 4 l). Thereafter, water also preheated to 78° C. to 82° C. is added (32 l, gives iPrOH/water=0.8:1). The solution already becomes cloudy and is then cooled to about 65° C. in 20 min, kept at this temperature for about 40 min, then cooled to about 40° C. in 70 min and stirred for a further 20 min. The product is isolated by centrifuging.
Table 2 shows the results of 4 batches.
TABLE 2______________________________________ Proportion* of Initial crystals of The concen- Final first crystal tration iPrOH/H.sub.2 O concentration modification Yield Batch [g/l] ratio [g/l] [%] [%]______________________________________1 600 4:1 600 n.d. 73.2 2 600 3:1 563 <0.4 71.4 3 400 2:1 333 <0.4 70.5 4 400 0.8:1 222 <0.4 85.6______________________________________ *The determination was carried out by Xray powder diffractometry; the proportion of the first crystal modification was always below the limit o detection, which was about 0.4%. n.d. means not determined
The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope. | The invention relates to a crystal modification of the compound of the formula I ##STR1## and the processes for the preparation of and use that crystal modifications 1. The invention is used for treating acute immunological episodes, such as sepsis, allergies, graft-versus-host and host-versus-graft-reactions, autoimmune diseases, in particular rheumatoid arthritis, systemic lupus erythematosus, multiple sclerosis, psoriasis, atopic dermatitis, asthma, urticaria, rhinitis, uveitis, type II diabetes, liver fibrosis, cystic fibrosis, colitis, cancers, such as lung cancer, leukemia, ovarian cancer, sarcomas, Kaposi's sarcoma, meningioma, intestinal cancer, lymphatic cancer, brain tumors, breast cancer, pancreatic cancer, prostate cancer, or skin cancer. | 2 |
FIELD OF THE INVENTION
The present invention relates to a process and equipment for improving froth quality, in terms of water and solids content, from oil sand bitumen extraction, which are particularly useful when processing problem oil sand ores such as those that have higher fines content and/or lower bitumen grade. More particularly, conditioned oil sand slurry prepared from oil sand ore and/or problem ores is introduced into a bitumen separation vessel where hotter underwash water is injected to form a stable, hot underwash water layer between the bitumen froth and middlings.
BACKGROUND OF THE INVENTION
Oil sand generally comprises water-wet sand grains held together by a matrix of viscous heavy oil or bitumen. Bitumen is a complex and viscous mixture of large or heavy hydrocarbon molecules which contain a significant amount of sulfur, nitrogen and oxygen. Oil sand deposits are typically extracted by surface mining. The mined oil sand is trucked to crushing stations for size reduction, and fed into slurry preparation units such as tumblers, cyclofeeders, and the like where hot water and, optionally, caustic are added to form a slurry for bitumen separation. The oil sand slurry may be screened through a screening device, where additional hot water may be added to clean the rejects prior to delivery to a rejects pile. The (screened) oil sand slurry is collected in a vessel and then pumped through a hydrotransport pipeline designed to condition and carry oil sand slurry from mining to extraction facilities to ensure sufficient conditioning of the oil sand slurry. During the conditioning stage in the hydrotransport pipeline, the aeration of slurry occurred where bitumen is attached to air bubbles, creating a lower density bitumen-air aggregates.
The conditioned slurry is then fed to a primary separation vessel (“PSV”). In the PSV, the slurry is allowed to separate under quiescent conditions for a prescribed retention period into a top layer of bitumen froth, a middle layer of middlings (i.e., warm water, fines, residual bitumen), and a bottom layer of coarse tailings (i.e., warm water, coarse solids, residual bitumen).
The interface between the bitumen froth and middlings is well defined when processing ores which are relatively high in bitumen content and low in fines content. “Fines” are particles such as fine quartz and other heavy minerals, colloidal clay or silt generally having any dimension less than about 44 μM. “Good ores” are oil sand ores having high bitumen content (10-12%) and relatively low fines content (less than about 20%). In contrast, “poor ores” are oil sand ores having low bitumen content (7-10%) and relatively high fines content (greater than 30%).
Poor ores typically do not segregate properly. The problem of “sludging” in the PSV is triggered by high fines content, and is characterized by the deterioration of the interface between the bitumen froth and middlings due to an increase in the density of the middlings. Coarser mineral particles and bitumen become entrapped in the process slurry as a result of non-segregating settling. Such conditions result in lower bitumen recovery and poorer quality of bitumen froth, leading to a decrease bitumen production capacity through the froth treatment plant. Attempts to alleviate this problem include manipulating operation variables such as, for example, total water, caustic dosage, ore blending, and throughput. A further problem encountered with bitumen froth quality is low froth temperature as a result of reducing the bulk processing temperature. Hence, this may lead to production capacity restrictions in downstream froth heating equipment.
SUMMARY OF THE INVENTION
The current application is directed to a process and apparatus for separating solids and bitumen from a conditioned oil sand slurry. The present invention is particularly useful with, but not limited to, problem ores, for example, ores having high amounts of fine solids which may interfere in bitumen separation, froth treatment, and tailings management. It was surprisingly discovered that by introducing a hotter underwash layer into a primary separation vessel at a controlled rate, the underwash water layer remained intact, with a steady-state thickness of water layer maintained between the upper froth layer and the lower middlings zone. One or more of the following benefits may be realized as direct results of the hot underwash layer:
(1) producing a more distinct interface between bitumen froth and middlings when controlling the feed rate of underwash relative to the feed rate of oil sand slurry, thereby resulting in better separation of bitumen froth from solids and water and also enhanced operability of the primary separation vessel as a result of clean water layer formed between froth and middlings layers;
(2) enhancing the froth quality by reducing water and solids content while increasing the bitumen content,
(3) providing additional heat to the bitumen froth via an underwash layer may sufficiently increase the froth temperature such that less hot water may be required as compared to conventional practices of heating the entire oil sand slurry by dilution with hot water (flood water) prior to slurry addition to the separation vessel;
(4) higher froth temperature may result in better deaeration of the bitumen froth, which is generally required prior to most conventional bitumen froth treatments; and
(5) conventional froth treatment processes which use centrifuges and inclined plate settlers are generally performed at 80° C.; however, when practicing the present invention, the froth may already be sufficiently heated for subsequent froth treatment.
Thus, use of the present invention allows for the redistribution of energy input into the bitumen recovery process from mined oil sand, thus, allowing for energy savings.
In one aspect, a process for removing solids and water from bitumen froth produced from an oil sand slurry is provided, comprising:
introducing the oil sand slurry into a separation vessel; retaining the oil sand slurry within the separation vessel so that separate layers of bitumen froth, middlings and sand tailings are formed; introducing sufficient heated water having a temperature greater than about 80° C. as an evenly distributed underwash layer beneath the bitumen froth layer; and separately removing the bitumen froth, middlings and sand tailings from the separation vessel.
In one embodiment, the heated water is at a temperature between about 80° C. and about 94° C. In another embodiment, the heated water is at a temperature greater than about 94° C. In one embodiment, the heated water is introduced into the separation vessel at a water to oil sand feed ratio of about 0.04:1 to about 0.1:1. It was surprisingly discovered that if the underwash is introduced at too low of an underwash to oil sand feed ratio, i.e., less than about 0.04:1, a complete underwash layer would not be formed. Increasing the ratio resulted in an increase in the thickness of the water layer between the bitumen froth and middlings, which would provide higher quality froth, i.e., lower solids.
In another aspect, an underwash injection assembly for use in a separation vessel for evenly distributing an underwash layer into the vessel is provided, comprising:
a main header having a flow meter for supplying heated water having a temperature of at least about 80° C. to an underwash distributor system which distributes the heated water to a number of manifolds connected to an outer ring header and a number of manifolds connected to an inner ring header; and
a downcomer connected to each manifold with substantially equal lengths of tubing.
In one embodiment, the tubing comprises flexible tubing. In another embodiment, the outer ring comprises 24 manifolds and the inner ring comprises 14 manifolds.
BRIEF DESCRIPTION OF THE DRAWINGS
Referring to the drawings wherein like reference numerals indicate similar parts throughout the several views, several aspects of the present invention are illustrated by way of example, and not by way of limitation, in detail in the figures, wherein:
FIG. 1 is a graph comparing froth temperature with and without injection of hot underwash water.
FIG. 2 is a graph comparing improvements in froth quality using an oil sand ore of 8.7 wt % in bitumen grade and 38 wt % in fines solids, and an oil sand ore of 11.5 wt % bitumen grade and 19 wt % in fines solids, at different underwash water:oil sand feed ratios.
FIG. 3 is a graph showing the effect of different temperatures of underwash water on froth temperature at different underwash water:oil sand feed ratios.
FIG. 4 is a schematic of an underwash distribution system useful for distributing heated water in a underwash distribution assembly of the present invention.
FIG. 5 is a schematic showing the inner and outer rings of the underwash distribution assembly of the present invention.
FIG. 6 is a schematic of a single downcomer of the underwash distribution assembly of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The detailed description set forth below in connection with the appended drawings is intended as a description of various embodiments of the present invention and is not intended to represent the only embodiments contemplated by the inventor. The detailed description includes specific details for the purpose of providing a comprehensive understanding of the present invention. However, it will be apparent to those skilled in the art that the present invention may be practiced without these specific details.
The present invention relates generally to a process and equipment for improving extraction froth product quality from problem oil sand ores such as those that have higher fines content and/or lower bitumen grade. The quality of bitumen froth is determined not only by the relative amounts of water and solids present in the material, but also by the ease with which such components can be separated from the froth within the bitumen separation vessel (PSV).
A conventional PSV generally defines a separation chamber having a cylindrical upper portion and a conical lower portion. The upper portion comprises a feedwell having an inlet through which the conditioned slurry enters the PSV at the upper portion of the separation chamber. The inlet is generally oriented tangential to the upper portion, thereby generating a swirling flow when feeding the slurry into the separation chamber. The PSV is generally equipped with a rake rotatably mounted within the lower portion of the PSV to rake the slurry slowly in a downward motion, thereby aiding in the separation process.
The PSV includes an underwash water distributor which introduces stable underwash water beneath the layer of bitumen froth. As used herein, the term “underwash water” means relatively clean heated water which is used to warm the froth. Since the specific gravity of water (1) lies between the specific gravities of froth (0.6-0.9) and middlings (1.1-1.4), a water layer can be maintained between the froth and middlings. The ascending aerated bitumen droplets thus passes immediately through a layer of hot underwash water before joining the froth, enhancing froth quality by washing rising aerated bitumen droplets and maintaining a mild downward current which depresses the fines to the middlings, thereby reducing the solids content entrained to the froth layer. Further, if the temperature of the water layer is higher than that of the middlings, the bitumen droplets rising through the water layer are heated, resulting in a higher froth temperature. In turn, a higher froth temperature reduces bitumen viscosity and allows the formation of a tighter froth with less water and solids.
In one aspect, the present invention relates to a process of introducing conditioned oil sand slurry prepared from problem ores into a bitumen separation vessel and having an improved underwash water distribution assembly which evenly injects and distributes hotter underwash water to form a stable, hot underwash water layer between the bitumen froth and middlings.
The process involves injecting a sufficient amount of underwash water having a temperature greater than about 80° C., preferably about 94° C. or greater, beneath the bitumen froth but above the middlings. The exit velocity of the underwash water should be less than 1 ft/s to minimize the turbulence in the vessel that will disrupt the formation of a stable water layer. In one embodiment, the underwash water comprises tumbler water used in the “hot water process,” whereby the as-mined oil sand is mixed in a tumbler with hot water (approximately 80-90° C.), caustic and naturally entrained air to yield the slurry that is later conditioned. Sufficient amounts of tumbler water and flood or dilution water may also be mixed together to yield an underwash water having a temperature of at least about 80° C., preferably about 94° C. or greater.
As described in the Examples, the use of hotter underwash water contributes to higher froth temperature, better froth quality in terms of lower froth water and solids content, better separation, vessel control and operability, and operation of the bitumen separation vessel at a lower temperature by using lower temperature flood water.
Once formed, the underwash water layer between the froth and middlings can be maintained unless disrupted by turbulence. If excessive turbulence is present, the water layer may disintegrate or necessitate additional injection of underwash water. Baffles are commonly included in bitumen separation vessels, as described in U.S. Pat. No. 3,520,415 to Cymbalisty and U.S. Pat. No. 3,567,621 to Gray et al. to reduce turbulence and to create a disengaging zone to minimize entrainment of solids in the froth layer. As used herein, the term “baffle” refers to a static flow-directing or obstructing vane or panel. Using the present invention with the exit velocity of <1 ft/s at the underwash discharge ports, it was found that a stable underwash water layer can be formed between the froth and middlings in a bitumen separation vessel without baffles.
The stability of the underwash water layer may be further improved by evenly injecting and distributing the hotter underwash water between the froth and middlings. In one aspect, the present invention relates to an improved underwash water distributor or injection assembly for optimizing the distribution of underwash water beneath the froth and middlings to form the stable water layer. In one embodiment, the injection assembly comprises an inner ring header and an outer ring header which are installed on the roof of the bitumen separation vessel. The inner ring header has a smaller diameter than that of the outer ring header. Both the inner and outer ring headers feed underwash water into injection conduits equidistantly spaced in relation to adjacent conduits, and extending below the PSV interface level.
Each injection conduit comprises an upper portion and a lower portion, and defines a bore extending therethrough between its ends to allow underwash water to flow downward from the respective inner ring or outer ring header. The upper portion has a diameter greater than that of the lower portion. A horizontal, annular shoulder is thus formed by the injection conduit at the junction of the upper and lower portions, and enlarges the area of the injection conduit to reduce the speed of the underwash water flow to <1 ft/s, thereby reducing turbulence at the discharge. The injection conduits may be constructed from any suitable piping as is employed in the art. Suitable piping includes, without limitation, plastic piping, galvanized metal piping, and stainless steel piping.
A deflector plate is connected to the end of the injection conduit by fastening bars to define a gap between the deflector plate and the end of the injection conduit. In one embodiment, the deflector plate is circular-shaped to deflect the water flow horizontally in all directions, and to prevent excessive dilution of the underwash water with the middlings.
The flow of underwash water through each injection conduit may be equalized by positioning a restriction orifice within the bore of the injection conduit. In one embodiment, the restriction orifice comprises a plate defining a central opening. Upon reaching the orifice plate, the underwash water is forced to converge to pass through the opening, resulting in velocity and pressure changes.
The flow of underwash water through each injection conduit may also be equalized by using valves. In one embodiment, each of the inner and outer ring headers comprises a pair of semi-circular portions having inlets at both ends. The inlets have associated valves which may be opened and closed to control the flow of the underwash water. The valves may comprise any suitable valve employed by those skilled in the art to permit, or prevent, the flow of the underwash water through an injection conduit. Suitable valves include, but are not limited to, butterfly valves, gate valves, and ball valves. In another embodiment, the design uses an equal length of flexible hose to connect the header to each downcomer. Therefore, each downcomer would have similar resistance and achieve a more hydraulic balance system to ensure equal water distribution. This design then eliminates the use of orifice and prevent plugging issues.
An embodiment of an underwash water distribution assembly useful in the present invention is shown in FIGS. 4-6 . In this embodiment, the froth underwash water distribution assembly utilizes a cascade froth underwash distributor system as shown in FIG. 4 . In this embodiment, all branches of the distribution system are designed to have equal hydraulic resistance, so that the flow is naturally split equally among them, without requirement for flow control by valves or orifices. Hot water is delivered to the main header 102 (e.g., 12 inch diameter pipe) with flow rate controlled by venture flow meter 104 . The water is divided into two (2) 10 inch headers 106 a , 106 b and each secondary header 106 a , 106 b supplies hot underwash water to half of the separation vessel (e.g., a PSV). For each secondary header 106 a , 106 b , there are nineteen (19) manifolds 108 , with twelve (12) manifolds 108 (A+D) for the outer ring 110 (shown in FIG. 5 ) and seven (7) manifolds 108 (B+C) for the inner ring 112 (shown in FIG. 5 ). Therefore, there are nineteen (19) manifolds 108 for each half of the PSV with a total of thirty-eight (38) manifolds 108 for the entire PSV.
Each manifold 108 is connected to a downcomer through equal length of flexible hose 116 , which preferably is ˜30 ft. A schematic of a downcomer 114 useful in the present invention is shown in FIG. 6 . In this embodiment, each downcomer 114 consists of a pipe 118 connecting to the flexible hose 116 and ending approximately 18″ below a typical PSV interface level. The top portion 120 of the pipe is 2 inches in diameter. The bottom portion 122 , which is 1.5 ft in length, has a diameter of 4 inch. A 6 inch circular deflector plate 124 is welded to the bottom with three rods, allowing for a 3″ gap between the deflector plate 124 and the end of the 4″ pipe. The purpose of the pipe expansion from 2″ to 4″ is to reduce the speed of the water flow, thus reducing the turbulence at the discharge. The downward velocity of the underwash water exiting the pipe is ˜1 ft/s. The deflector plate is installed to deflect the water flow and prevent excessive underwash water dilution with the middlings' layer.
Exemplary embodiments of the present invention are described in the following Examples, which are set forth to aid in the understanding of the invention, and should not be construed to limit in any way the scope of the invention as defined in the claims which follow thereafter.
Example 1
Tests were conducted to assess the formation of a stable underwash water layer between the froth and middlings within a bitumen separation vessel without baffles. The horizontal fluid velocity at the PSV interface was estimated to be in the range of 0.7 to 1.5 ft/s. In one test, cold water was used as a tracer and confirmed that a stable underwash water layer formed between the froth and middlings.
In a further test, the temperature of the froth was sampled at different vertical distances (inches) below the surface of the separation vessel following injection of underwash water (“U/W on”) having a temperature of 94° C. The test results indicate that the froth temperature ranged from about 80-83° C. between about 7″-53″ below the surface of the separation vessel ( FIG. 1 ). The froth temperature dropped to about 73° C. between about 55″ to 60″ below the surface of the separation vessel. Without injection of underwash water (“no U/W”), the froth temperature was about 71° C., which remained relatively constant at the PSV slurry temperature. Without being bound by theory, it is expected that the use of hotter underwash water allows the bitumen separation to occur at a lower temperature, but will not have any effect on the froth temperature as the bitumen-air aggregates rising through the hot underwash water layer will be heated.
Example 2
Testing was conducted using an oil sand ore of 8.7 wt % in bitumen grade and 38 wt % in fines solids, an oil sand ore of 11.5 wt % in bitumen grade and 19 wt % in fines solids, and underwash water having different temperatures to test the effect of temperature and the underwash water to oil sand feed ratio on froth quality. The froth bitumen content increased by a maximum of 23% using an underwash water:ore feed ratio of 0.10 for the 8.7% grade oil sand, and by a maximum of 9% using an underwash water:ore feed ratio of 0.11 for the 11.5% grade oil sand at the underwash water temperature of 94° C. ( FIG. 2 ). The underwash water temperature had more impact on froth bitumen enrichment for the “poor” oil sands than for the “good” oil sands. The test results are summarized in Table 1 below.
TABLE 1
U/W
Water
Average
Average
U/W Water
to Ore
Froth Quality
Grade
Fines
Temperature
Feed
Bitumen
Water
Solids
(%)
(%)
(° C.)
Ratio
(%)
(%)
(%)
11.5
19
65
0.076
64.39
25.27
10.34
94
0.075
63.91
25.80
10.29
94
0.074
63.61
25.77
10.62
94
0.046
62.61
27.50
9.89
94
0.084
64.28
26.77
8.95
N/A
0.000
58.95
31.77
9.28
8.7
38
N/A
0.000
37.25
48.59
14.16
94
0.099
59.81
33.12
7.07
94
0.098
57.28
35.73
6.99
56
0.099
52.14
40.00
7.86
80
0.096
55.92
36.48
7.60
80
0.052
58.45
34.26
7.29
80
0.073
53.78
38.62
7.60
N/A
0.000
36.66
50.92
12.42
By comparing conditions with and without froth underwash water, the average reductions (%) in the water:bitumen ratio and the solids:bitumen ratio were calculated. Solids reduction included all size ranges including solids below 20 μm. The test results are summarized in Table 2 below. Again, the use of underwash has water to bitumen and solids to bitumen ratios reduction higher for the “poor” ores than for the “good” ores.
TABLE 2
Average Reduction (%)
Oil Sand Grade
Water to
Solids to
(wt % Bitumen)
bitumen ratio
bitumen ratio
8.7
54
62
11.5
28
17
The effect of different temperatures of underwash water on froth temperature at different underwash water:oil sand feed ratios was also determined. A maximum increase of 14° C. in froth temperature was achieved using underwash water having a temperature of 94° C. and an underwash water:ore feed ratio of 0.10 ( FIG. 3 ). The test results are summarized in Table 3 below.
TABLE 3
Froth Bitumen
Average
Average
U/W Water
U/W Water
Content
Grade
Fines
to Ore
Temperature
Enhancement
(%)
(%)
Feed Ratio
(° C.)
(%)
11.5
19
0.075
94
4.8
0.076
65
5.4
8.7
38
0.10
94
21.6
0.10
80
19.0
0.10
56
15.2
Overall, the results clearly show a significant improvement in froth quality when hotter underwash water (94° C.) was used, in particular, for the “poor” ores.
Example 3
A field test was conducted to assess the ability of a modified underwash water distributor to form a stable water layer between the froth and middlings. The water addition pipes were spaced at 8′ to 10′ apart, and oriented below inner and outer ring headers installed on the roof of the bitumen separation vessel. The smaller inner ring header fed fourteen injection points, while the larger outer ring header fed twenty-four injection points. Equal length of flexible hose is used to connect the header to each downcomer, hence each downcomer will have equal hydraulic resistance to ensure equal water distribution. Each injection point consisted of pipe originating from the header and ending 18 ″ below a typical PSV interface level. The top portion of the pipe was 2″ in diameter, while the bottom portion was 1.5° in length and 4″ in diameter. A 6″ circular deflector plate was welded to the bottom of the pipe by three rods, allowing for a 3″ gap between the deflector plate and the end of the 4″ pipe. The downward velocity of the underwash water exiting the pipe was about 1 ft/s. A stable underwash water layer was observed between the froth and middlings.
From the foregoing description, one skilled in the art can easily ascertain the essential characteristics of this invention, and without departing from the spirit and scope thereof, can make various changes and modifications of the invention to adapt it to various usages and conditions. Thus, the present invention is not intended to be limited to the embodiments shown herein, but is to be accorded the full scope consistent with the claims, wherein reference to an element in the singular, such as by use of the article “a” or “an” is not intended to mean “one and only one” unless specifically so stated, but rather “one or more”. All structural and functional equivalents to the elements of the various embodiments described throughout the disclosure that are known or later come to be known to those of ordinary skill in the art are intended to be encompassed by the elements of the claims. Moreover, nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims. | A process for enhancing the froth quality, improving vessel operability and increasing the froth temperature from an oil sand slurry in a primary separation vessel is provided, comprising introducing the oil sand slurry into a separation vessel; retaining the oil sand slurry within the separation vessel so that separate layers of bitumen froth, middlings and sand tailings are formed; introducing sufficient heated water having a temperature greater than about 80° C. as an evenly distributed underwash layer beneath the bitumen froth layer; and separately removing the bitumen froth, middlings and sand tailings from the separation vessel. | 2 |
This application is a continuation of application Ser. No. 07/256,399, filed Oct. 11, 1988, now abandoned.
BACKGROUND OF INVENTION
This invention relates to electronic musical instruments and, more particularly, to a technology for designating how a tone generator synthesizes musical tones.
Electronic musical instruments with a tone generator for synthesizing musical tones using a plurality of waveform generation modules are known in the art. Such waveform generator modules can be connected to one another in various forms, and the entirety of the resultant connected structure specifies the way of synthesizing tones.
An electronic musical instrument disclosed in U.S. Pat. No. 4,554,857 (issued on Nov. 26, 1985) incorporates a set of tone synthesis algorithms each defining a connected structure of a plurality of waveform generator modules. Each tone synthesis algorithm has a uniquely assigned numerical value representing the name of the algorithm. A tone synthesis algorithm is specified by selecting an algorithm number by an input unit. The selected tone synthesis algorithm is executed by a tone generator having a plurality of time-division multiplexed (TDM) modules for the synthesis of a tone.
With this arrangement, the user can select a tone synthesis algorithm but can not program it, i.e., assemble a connected structure of the plurality of tone generator modules. Further, with the increase of the number of tone synthesis algorithms, it becomes difficult for the user to grasp the correspondence between numbers and tone synthesis algorithms.
Further, the tone generator used in the above system is basically of the frequency modulation (FM) type. Therefore, the output of a module is usable in only two alternatives, one for partial output of the tone generator, and the other for part of a phase signal input to the same or a different module.
U.S. patent application Ser. No. 002,121, filed on Jan. 12, 1987, concerning the assignee of this application discloses a tone generator with a plurality of TDM modules, which can utilize the output of each module in various ways, for instance, as part of a synthesized tone, an envelope input to a different module or part thereof or a phase input to a different module or part thereof. Therefore, the number Of tone synthesis algOrithms executable by the tone generator is extremely large and may readily exceed 100,000 for eight modules. The application, however, does not show any technique that permits the user to select or assemble a tone synthesis algorithm.
SUMMARY OF THE INVENTION
An object of the present invention is to provide an electronic musical instrument which allows the user to easily program a configuration of tone synthesis.
Another object of the invention is to provide an electronic musical instrument in which a tone generator can synthesize tones in various ways according to selected tone synthesis algorithms.
A further object of the invention is to provide an electronic musical instrument which permits the user to make the best use of the tone synthesis capacity of a tone generator having a plurality of time-division multiplexed modules.
In accordance with the present invention, there is provided an electronic musical instrument with a tone generator for synthesizing musical tones by using a plurality of time-division multiplexed waveform generator modules, which comprises input means for designating a connection structure of each pair of modules independently of the connection structures of other module pairs such that each module pair forms a tone synthesis unit, and processing means for generating control data for each module in response to the designation by the input means and for transferring the generated control data to the tone generator.
This arrangement has an advantage that the user can readily program a tone synthesis algorithm. Further, in contrast to the prior art, there is no need for the user to confirm the correspondence between numerical values and structures of a plurality of modules.
Preferably, the input means selects each module pair connection structure from:
(a) a mode in which the output of the first or former module in the pair is added to the output of the second or latter module in the pair;
(b) a mode in which the output of the former module is used as a phase signal to the latter module; and
(c) a mode in which the output of the former module is used as part of an envelope signal to the latter module.
There may be further provided display means which visually displays a connected structure of a plurality of modules in response to the designation by the input means.
The electronic musical instrument may further comprise additional input means for independently designating a connection structure of each pair of the tone synthesis units.
With this addition, the number of programmable tone synthesis algorithms is further increased, permitting the user to take full advantage of the tone generator capacity.
Preferably, additional input means selects a connection structure of each pair of tone synthesis units from:
(a) a mode in which the output of the preceding tone synthesis unit in the pair is used as at least part of a phase signal to the latter module in the succeeding tone synthesis unit in the pair; and
(b) a mode in which the output of the preceding tone synthesis unit in the pair is used as at least part of a tone to be output from the tone generator.
Module control data may contain phase distortion control data. In this relation, each module may include means for receiving a phase signal, means for modulating the received phase signal according to the phase distortion control data, sine wave memory means, means for accessing sine wave memory means by using the modulated phase signal, means for receiving an envelope signal and means for multiplying the received envelope signal by an output signal from the sine wave memory means.
The phase signal may be selected according to the module control data from a phase signal from basic parameter generator means, an output signal from the former module, an output signal of the previous tones synthesis unit and the sum of or difference between the output signal of the former module and the output signal from the previous tone synthesis unit. The envelope signal may be selected according to the module control data from an envelope signal from the basic parameter generator means and the sum of the output of the preceding module and the envelope signal from the basic parameter generator means.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other objects, features and advantages of the invention will become more apparent from the following detailed description with reference to the accompanying drawings, in which:
FIG. 1 is a block diagram of an electronic musical instrument in accordance with the invention;
FIG. 2 is a block diagram of a tone generator LSI useful instrument;
FIG. 3 shows logical arrangement of a waveform generator for use in the tone generator;
FIG. 4 shows correspondence between operation codes and operations of the waveform generator;
FIG. 5 is a view of an input unit in a first embodiment;
FIG. 6 is a schematic diagram of the waveform generator in the first design, showing respective tone synthesis units;
FIG. 7 is a schematic diagram of the first tone synthesis unit in FIG. 6;
FIG. 8 shows correspondence between operation codes and respective modes of addition, phase and ring modulation of two consecutive modules;
FIG. 9 shows waveform synthesis registers storing instructions of tone synthesis provided by the input unit shown in FIG. 5;
FIG. 10 is a flow chart for generating operation codes for the waveform generator from the contents of the waveform synthesis registers;
FIG. 11 is a view of an input unit in a second embodiment;
FIG. 12 is a schematic diagram of the waveform generator in the second embodiment, showing respective tone synthesis units;
FIG. 13 is a schematic diagram of first two units in FIG. 12;
FIG. 14 shows correspondence between operation codes and the respective positions of the select switches in FIG. 13;
FIG. 15 shows waveform synthesis registers storing instructions of tone synthesis provided by the input unit shown in FIG. 11; and
FIG. 16 is a flow chart for generating operation codes for the waveform generator from the contents of the waveform synthesis registers shown in FIG. 15.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Now, an embodiment of the invention will be described with reference to the drawings. FIG. 1 is a block diagram of an electronic musical instrument incorporating the features of the invention. The states of a keyboard 1 and a switch section 2a, are monitored by CPU 3 to detect key-"on", key-"off", tone color selection, etc. Data concerning the selected tone color, edit, etc. are presented on a display section 2b by CPU 3. For the control of a tone generator LSI 6, the CPU 3 generates the necessary data using a ROM 4 and a RAM 5 and transfers the generated data to the tone generator LSI 6. The tone generator 6 uses an external RAM 7 as an operation buffer to generate tones. The generated tones are converted by a digital-to-analog converter (DAC) into analog signals, which are amplified by an amplifier 9 and sounded by a loudspeaker 10.
FIG. 2 shows a block diagram of the tone generator LSI 6. In this example, the tone generator LSI 6 has an 8-channel structure having 8 modules per channel. An interface/controller 11 provides an interface between CPU 3 and the tone generator LSI 6. It generates timing signals used in various parts of the tone generator LSI 6. Also, it decodes the data transferred from the CPU 3 and writes the decoded data in the external RAM 7 through an external RAM interface 16. An envelope and keycode generator 12 reads and writes data from and in the external RAM 7 via the external RAM interface 16 and generates and supplies envelope and keycode data to an exponential transformation and phase angle generation unit 13. The unit 13 performs exponential transformation of the supplied envelope and keycode data and accumulates the transformed keycode data (differential value of the phase) to generate the phase angle data. In the present example, the envelope and keycode generator 12 samples envelope and keycode data at a relatively low rate because it uses the external RAM 7. On the other hand, the waveform generator 15 samples tones at a high rate. For this reason, the exponential transformation and phase generator unit 13 carries out the rate conversion using an internal buffer (not shown). As a result, the exponential transformation and phase angle generation circuit 13 supplies the phase angle and envelope data to the waveform generator 15 at each channel and module time, maintaining synchronization with the waveform generator 15. An OC register 14 includes a memory for storing data (operation codes) for controlling the operation of the waveform generator 15 for each channel and module. The memory is updated via the interface/controller 11 every time an operation code is transferred from CPU 3. At each channel and module time of the waveform generator 15, the OC register 14 reads out a corresponding operation code from the internal memory and supplies it to the waveform generator 15. The waveform generator 15 selectively uses time-division multiplexed envelope and phase angle data supplied from the exponential transformation and phase angle generation circuit 13 according to time-division multiplexed operation code data for each channel and module provided by the OC register 14 to generate various tones.
FIG. 3 illustrates a logical arrangement of the waveform generator 15. A portion surrounded by the dashed rectangle indicates a waveform generator module 15M which operates on TDM basis. In the Figure, labeled E and ωt are time-division multiplexed envelope data and phase angle data supplied by the exponential transformation and phase angle generation circuit 13 at each channel and module time. The states of selectors XS, ES, TS and SS in the waveform module 15M are each controlled by operation codes provided from the OC register 14 at each channel and module time. The selection circuit XS is for selecting a phase angle used in the waveform module 15M. The phase angle selector XS selects the phase angle according to the operation code from:
(a) phase angle data generated by the exponential transformation and phase angle generation circuit 13;
(b) waveform output W -1 of an immediately preceding module;
(c) output R of temporary register 15-3; or
(d) sum of or difference between (b) and (c).
Designated by ES is an envelope selection circuit which selects;
(a) envelope data E generated by the exponential transformation and phase angle generation circuit 13 when the bit 3 of the operation code OC is "0", and
(b) the past or accumulated waveform R' from the temporary register 15-3 added to the envelope data E when the bit 3 of the operation code OC is "1".
Designated by PD is a phase distortion/noise selection circuit which selects:
(a) no phase distortion when the bits 2 to 0 of the operation code OC is "0",
(b) five progressive phase distortions when the value of the bits 2 to 0 is "1" to "5",
(c) white noise when the value of the bits 2 to 0 is "6", and
(d) the product of white noise and sinusoidal wave, i.e., pink noise, when the value of the bits 2 to 0 is "7".
If no phase distortion is selected the waveform module 15M converts a phase selected by the phase angle selector XS into a sinusoidal wave at that phase using a SINROM 15-1 and multiplies it by an envelope selected by the envelope selector ES using a multiplier 15-2. The output of the multiplier defines the output W of the waveform module 15M.
TS is a circuit for selecting an input to the temporary register 15-3. TS selects the input according to the operation code from:
(a) waveform output W of the current module,
(b) output R of the temporary register, or
(c) sum of or difference between (a) and (b).
SS selects an input to an accumulator 15-4 which accumulates waveforms to form a tone to be supplied to DAC 8.
The input to the accumulator is either:
(a) the result of addition or subtraction of the waveform W of the current module to or from existing accumulated waveform, or
(b) existing accumulated waveform (without change).
Thus, the accumulator input selector SS controls whether to use the waveform output W of the current module as part of a tone to be output from the waveform generator 15.
FIG. 4 shows correspondence between operation codes and operations of the waveform module 15M. A suffix 1 in the Figure indicates an ordinal module number. For example, when the operation code OC is 0X (hexadecimal notation), the input to the accumulator 15-4 is the sum of whatever is in the accumulator Σ and waveform output W i-1 of the preceding module, while the phase angle input X 1 to the current module is given by the phase data ω i t from the exponential transformation and phase angle generation circuit 13.
This invention concerns a technique of designating an operation mode of each TDM waveform module in a tone generator as exemplified by the waveform generator 15. By way of example, two embodiments will be described.
First Embodiment
In a first embodiment or design, a way of combining or interconnecting individual pairs of the modules can be designated using an input unit. There are three ways or modes of combination, i.e., addition mode, phase mode and ring modulation mode. Let E i sin ω i t, be the output waveform of module i. In the addition mode we obtain
E.sub.i sin ω.sub.i t+E(i+1) sin ω(i+1)t.
In the phase mode, the output waveform of the module i constitutes the phase of the next module i+1, so we have
E(i+1) sin (E.sub.i sin ω.sub.i t).
In the ring modulation mode, the output waveform of module i is added to the envelope E(i+1) produced by the exponential transformation and angle generation circuit 13 to define an envelope used in the waveform module i+1. Thus, we obtain
(E(i+1)1+E i sin ω i t) sin ω(i+1)t.
FIG. 5 shows an example of the input unit for designating the above three modes of combination. In the Figure, designated by 2b-1 is a display section. The waveform generator 15 synthesizes a tone using a total of eight modules. If two modules are called a line as a unit (tone synthesis unit), there are a total of four lines. The actual waveform generator 15 noted above can generate tones for eight channels each consisting of eight modules. The following description, however, assumes a single channel for the sake of brevity. Numerals 0 to 3 shown on the left side of the screen of the display 2b-1 represents line numbers. For example, line 0 is a combination of modules 0 and 1. The way of combining each pair of modules is displayed on the right side of the corresponding line number. A line is selected by a cursor key 2a-1, and the way of combination of the pair of modules (addition phase or ring modulation mode) is selected by a value key 2a-2. For example "ADD", in the Figure, means that modules 0 and 1 are added together. The display section 2b-1 is part of the display 2b shown in FIG. 1. The keys 2a-1 and 2a-2 form part of the switch section 2a.
FIG. 6 schematically shows the waveform generator 15 when eight TDM modules of the waveform generator 15 are regarded as four tone synthesis units or lines L 0 to L 3 .
FIG. 7 shows the first tone synthesis line L 0 . The functions of the waveform generator 15 described in conjunction with FIG. 3 are shown here in a simplified form for the sake of explanation of the first design. For example, designated by 15-1 0 is SINROM 15-1 in the module 0, and 15-1 1 is SINROM 15-1 in the module 1. The output of E 0 is an envelope generated by the exponential transformation and phase angle generation circuit 13 (FIG. 2) at a time of module 0, and the output of E 1 is an envelope generated by the circuit 13 at a time of module 1. The other lines L 1 to L 3 are similarly arranged. The relation between the module 0 and 1 can be selected from three modes, i.e., "addition", "phase" and "ring modulation" modes, by means of three select switches SW1 to SW3 shown in the Figure.
FIG. 8 shows correspondence between two operation codes OC0 and OC1 for the respective modules 0 and 1 and the select switches SW1 to SW3 in FIG. 7. OC0 and OC1 on the first row state that the two modules be added. In the case of OC0 and OC1 on the second row, the output of the preceding module (module 0) becomes the phase of the succeeding module (module 1). OC0 and OC1 on the third row indicates the ring modulation.
FIG. 9 shows waveform synthesis registers MD01, MD23, MD45 and MD67 set by the input unit shown in FIG. 5. These registers are provided in the RAM 5 shown in FIG. 1. The lowest two bits of each register specifies the relation between two modules. The CPU 3 in FIG. 1 generates each operation code from the contents of each register and transfers it to the OC register 14 of the tone generator LSI 6.
FIG. 10 shows a flow chart of generating operation codes OC as done by CPU 3. The CPU 3 checks the lowest two bits of each of the registers MD01, MD23, MD45 and MD67 in the steps S0, S4, S8 and S12. If the lowest two bits are "00" representing an addition, the CPU makes the operation code for the preceding module equal to "00" and the operation code for the succeeding module equal to "00" (steps S1, S5, S9 and S13). As is seen from FIGS. 4 and 8, with this combination of operation codes, the waveform generator 15 executes addition of two modules. When the lowest two bits are "01" representing a phase operation, the operation codes of the preceding and succeeding modules are respectively "00" and "A0" (steps S2, S6, S10 and S14). As a result, the waveform generator 15 selects the output of the preceding module as the phase input to the succeeding module. When the lowest two bits are "1X" (where X is a "don' t care" bit) representing a ring modulation operation the operation codes of the preceding and succeeding modules are respectively "00" and "88" (S3, S7, S11 and S15). As a result, the envelope used in the succeeding module i+1 is given by
(E.sub.(i+1) +E.sub.i)sin ω.sub.i t
and the ring modulation is achieved.
Since there are three different ways of combining two modules, a total of eight modules reside in the tone generator, and each tone synthesis line is independent of the others, there are a total of 3 4 i.e., eighty one possible tone synthesis combinations.
In this manner, the first embodiment regards the eight TDM waveform modules provided in the waveform generator 15 as four different pairs of modules, and allows the connection structure of each module pair (line) to be selected using the input unit.
Second Embodiment
A second embodiment or design allows, in addition to the requirements of the first design, the waveform output of the current line to be used as either
(a) a phase input to the latter module of the next line or part of the input, or
(b) a tone.
By adding the selection (a), the module phase input may contain a plurality of frequency components, thus enriching tones generated.
FIG. 11 shows an input unit for use in the second design. As is seen from the screen of a display section 2b-1, it is possible to select both the relation of two modules constituting a line (i.e., either addition, phase or ring modulation) and the relation of the current line with the next. "ON" shows that the current line output is supplied to the input of the next line. "OFF" shows that the line output is not supplied as the input to the next line but is used as a tone. A cursor key 2a-1 selects a line number, or a value key 2b-1 selects the line-setting data.
FIG. 12 schematically shows the waveform generator 15 in the second design. The second design is the same as the first insofar as two consecutive modules are regarded as a single tone synthesis line but is different in that each line output can be input to the next line.
FIG. 13 shows an arrangement of the first and second tone synthesis line L 0 and L 1 in FIG. 12.
Select switches SW1 to SW 3 in the unit L 0 and select switches SW5 to SW7 in the unit L 1 serve to select module relation in each line from the addition, phase and ring modulation modes. Select switches SW4 and SW8, which are additionally provided in the second design, determine whether the line output is supplied to the next line or used as a tone.
In FIG. 13, if the select switch SW4 has its pole thrown to the left, the output α 0 of the line L 0 is supplied to the next line L 1 . The line L 1 provides
E.sub.3 sin (α.sub.0)+E.sub.2 sin ω.sub.2 t,
E.sub.3 sin (α.sub.0 +E.sub.2 sin ω.sub.2 t), and
(E.sub.3 +E.sub.2 sin ω.sub.2 t) sin (α.sub.0)
when the switches SW5, SW6 and SW7 are in the center, lower and left positions, in the upper, lower and right positions and in the center, upper and right positions, respectively. Generally, when the output α i/2-1 of the line i/2-1 is supplied to the next line 1/2, the output of the latter is either
E(i+1) sin (α.sub.i/2-1)+E.sub.i sin ω.sub.i t,
E(i+1) sin (α.sub.i/2-1 +E.sub.i sin ω.sub.i t), or
(E(i+1)+E.sub.i sin ω.sub.i t) sin (α.sub.i/2-1).
FIG. 14 shows correspondence between operation codes and positions of select switches SW1 to SW8. For example, when OC0="00", OC1="80", OC2="40" and OC3="10" as seen in the first row, the output of the first line L 0 is
E.sub.0 sin ω.sub.0 t+E.sub.1 sin ω.sub.1 t.
This output constitutes the phase input to the second line L 1 . The module 3 of L 1 provides
E.sub.3 sin (E.sub.0 sin ω.sub.0 t+E.sub.1 sin ω.sub.1 t).
This output is added to the output E 2 sin ω 2 t of the module 2 of the line L 1 . More specifically, this is read from FIGS. 3 and 4. With OC="00" a waveform E 0 sin ω 0 t is generated by the module 0. This is supplied to the temporary register 15-3 in FIG. 3 (R=E 0 sin ω 0 t) with OC1 ="80". Further, with OC1="80" a waveform E 1 sin ω 1 t is generated by the module 1, and with OC2="40" this waveform is added to the previous E 0 sin ω 0 t, the sum being supplied to the temporary register 15-3 (R=E 0 sin ω 0 t+E 1 sin ω 1 t). Further, with OC2="40" a waveform E 2 sin ω 2 t is generated by the module 2, and with OC3="10" the content E 0 sin ω 0 t+E 1 sin ω 1 t of the temporary resister 15-3 is supplied as phase input to the module 3. The module 3 provides an output E 3 sin (E 0 sin ω 0 t+E 1 sin ω 1 t), and with OC3="10" the waveform E 2 sin ω 2 t from the module 2 is supplied to the accumulator 15-4 (Σ=E 2 sin ω 2 t). Although not shown in FIG. 14, the operation code OC4 of the next module is "00" (see FIG. 16 to be described later). Thus, the output of the module 3 is added to the waveform of the preceding module 2 and supplied to the accumulator 15-4 (Σ=E 2 sin ω 2 t+E 3 sin (E 0 sin ω 0 t+E 1 sin ω 1 t).
FIG. 15 shows waveform synthesis registers MD01, MD23, MD45 and MD67 which are altered by the input unit shown in FIG. 11. As in the first design, each lowest two bits designate the relation of two modules forming a line. Each bit 2 serves to determine whether the line output is to be provided as phase input to the next line or a tone. The CPU 3 generates operation codes for respective modules from these waveform synthesis registers MD01, MD23, MD45 and MD67 and transfers these codes to the OC register 14 of the tone generator.
FIG. 16 is a flow chart of generating operation codes as is done by the CPU 3. This will now be described in conjunction with some examples of tone synthesis.
The synthesis of E 2 sin ω 2 t+E 3 sin (E 0 sin ω 0 t+E 1 sin ω 1 t) has been described. In this case, MD01="04", and MD23="00". In the routine, OC0="00", OC1="80", OC2="40", OC3="10" and OC4="00" are generated through steps T1, T2, T3, T6, T33 and T34.
Now, synthesis of E 3 sin (E 2 sin ω 2 t+E 1 sin ω 1 t+E 0 sin ω 0 t) will be considered. In this case, MD01="40", and MD23="01". According to the routine, OC0="00", OC1 ="80", OC2="40", OC3="70" and OC4="00" are generated (steps T1, T2, T3, T6, T33 and T35). The synthesis operation is the same as the first example up to OC2. In the next OC3, the phase input X 3 receives
W.sub.2 +R=E.sub.2 sin ω.sub.2 t+E.sub.1 sin ω.sub.1 t+E.sub.0 sin ω.sub.0 t.
Thus, the output W 3 of the module 3 is given by
E.sub.3 sin (E.sub.2 sin ω.sub.2 t+E.sub.1 sin ω.sub.1 t+E.sub.0 sin ω.sub.0 t).
This is supplied to the accumulator with the next operation code OC4="00" stating
Σ=Σ+W.sub.3.
Now, the synthesis of (E 3 +E 2 sin ω 2 t) sin (E 1 sin ω 1 t +E 0 sin ω 0 t) will be considered. In this case, MD01="04", and MD23="02". The routine generates OC0="00", OC1="80", OC2="40", OC3="98" and OC4="00" (steps T1, T2, T3, T6, T33 and T36). This example is the same as the preceding examples up to OC2. With OC3="98", the output R (=E 1 sin ω 1 t+E 0 sin ω 0 t) of the temporary register 15-3 is selected as the phase input X 3 to the module 3, and E 3 +R' (R'=W 2 =E 2 sin ω 2 t) is selected as the envelope input. The module 3 provides (E 3 +E 2 sin ω 2 t) sin (E 1 sin ω 1 t+E 0 sin ω 0 t) which is then supplied to the accumulator 15-4 with OC4.
Now, when providing E 3 sin (E 2 sin ω 2 t+E 1 sin (E 0 sin ω 0 t)), MD01="05" and MD23="01". Thus, the routine generates OC0="00", OC1="A0", OC2="80", OC3="70" and OC4="00" (steps T1, T2, T4, T6, T33 and T35). Up to OC2 this example is the same as the preceding examples. With OC3
X.sub.3 ←R+W.sub.2
is executed, and with OC4
Σ←Σ+W.sub.3
is executed, to obtain
W.sub.3 =E.sub.3 sin (W.sub.2 +R)=E.sub.3 sin (E.sub.2 sin ω.sub.2 t+E.sub.1 sin (E.sub.0 sin ω.sub.0 t))
When providing (E 3 +E 2 sin ω 2 t) sin (E 1 sin (E 0 sin ω 0 t)), MD01="05" and MD23="02". Thus, OC0="00", OC1 ="A0", OC2="80", OC3="98" and OC4="00" are generated in the routine (steps T1, T2, T4, T6, T33 and T36). This example is the same as the preceding examples up to OC2. With OC3
X.sub.3 ←R(=E.sub.1 sin (E.sub.0 sin ω.sub.0 t)).
Then,
R'←W.sub.2 (=E.sub.2 sin ω.sub.2 t)
and then
W.sub.3 ←(E.sub.3 +R') sin X.sub.3
are executed. With OC4
Σ←Σ+W.sub.3
is executed. Here we have
W.sub.3 =(E.sub.3 +E.sub.2 sin ω.sub.2 t) sin (E.sub.1 sin (E.sub.0 sin ω.sub.0 t)).
In any of the first three examples, the line L 0 performs addition, and in the latter two examples the line L 0 uses the module 0 output as the phase to the module 1. When the line L0 is in the ring modulation mode, MD01="06", and OC0="00", OC1="88" and OC2="80" (step T4). With OC0
X.sub.0 ←ω.sub.0 t
is executive, and with OC1
X.sub.1 ←ω.sub.1 t,
R←W.sub.0 (E.sub.0 sin X.sub.0 =E.sub.0 sin ω.sub.0 t) and
W.sub.1 ←(E.sub.1 +R) sin X.sub.1
are executed. Thus, we have
W.sub.1 =(E.sub.1 +E.sub.0 sin ω.sub.0 t) sin ω.sub.1 t.
This is then stored in R with OC2. Thereafter, the line L 1 is designated in the same way as in the above examples. Thus, R i, e., contents of the temporary register 15-3 are used in one of the following:
E.sub.3 sin R+E.sub.2 sin ω.sub.2 t,
E.sub.3 sin (R+E.sub.2 sin ω.sub.2 t) or
(E.sub.3 +E.sub.2 sin ω.sub.2 t) sin R.
For example, when synthesizing E 7 sin (E 5 sin (E 3 sin (E 1 sin ω 1 +E 0 sin ω 0 t)+E 2 sin ω 2 t)+E 4 sin ω 4 t)+E 6 sin ω 6 t, MD01="04", MD23="04", MD45="04" and MD67="00". In the routine, OC0="00", OC1="80", OC2="40", OC3="90", OC4="40", OC5="90", OC6="40" and OC7="10" are generated as the operation codes (step T1, T2, T3, T6, T7, T8, T11, T12, T13, T16 and T17). Using suffix as module numbers of waveform generator 15M, respective functions of OC0 to
OC0: Σ←W.sub.7 +Σ, X.sub.0 ←ω.sub.0 t
OC1: R.sub.1 ←W.sub.0, X.sub.1 ←ω.sub.1 t
OC2: R.sub.2 ←W.sub.1 +R.sub.1, X.sub.2 ←ω.sub.2 t
OC3: R.sub.3 ←W.sub.2, X.sub.3 ←R.sub.2
OC4: R.sub.4 ←W.sub.3 +R.sub.3, X.sub.4 ←ω.sub.4 t
OC5: R.sub.5 ←W.sub.4, X.sub.5 ←R.sub.4
OC6: R.sub.6 ←W.sub.5 +R.sub.5, X.sub.6 ←ω.sub.6 t
OC7: Σ←W.sub.6, X.sub.7 ←R.sub.6
The final contents Σ of the accumulator 15-4 are Σ=W 7 +W 6 =E 7 sin X 7 +E 6 sin X 6 =E 7 sin R 6 +E 6 sin ω 6 t. Here,
R.sub.6 =W.sub.5 +R.sub.5 =E.sub.5 sin X.sub.5 +W.sub.4 =E.sub.5 sin R.sub.4 +E.sub.4 sin ω.sub.4 t,
where
R.sub.4 =W.sub.3 +R.sub.3 =E.sub.3 sin X.sub.3 +W.sub.2 =E.sub.3 sin R.sub.2 +E.sub.2 sin ω.sub.2 t,
where
R.sub.2 =W.sub.1 +R.sub.1 =E.sub.1 sin X.sub.1 +W.sub.0 =E.sub.1 sin ω.sub.1 t +E.sub.0 sin X.sub.0 =E.sub.1 sin ω.sub.1 t+E.sub.0 sin ω.sub.0 t.
Therefore, the final output is
E.sub.7 sin (E.sub.5 sin (E.sub.3 sin (E.sub.1 sin ω.sub.1 t+E.sub.0 sin ω.sub.0 t) +E.sub.2 sin ω.sub.2 t)+E.sub.4 sin ω.sub.4 t)+E.sub.6 sin ω.sub.6 t.
As has been shown, in the second design either the addition, phase or ring modulation mode can be selected for each module pair or line. It is also possible to make a selection as to whether the result of each line is used as the phase or partial phase input to the latter module of the next line or provided as a tone. The waveform generator 15 operates a total of eight TDM modules, so that 3 4 *2 3 =648 different tone synthesis combinations are possible.
While preferred embodiments of the invention have been described, various changes and modifications are obvious to a person having an ordinary skill in the art without departing from the scope of invention. For example, the display unit may provide a graphic representation of the connection structure of a plurality of modules. Thus, the scope of the invention should be defined solely by the appended claims. | An electronic material instrument includes a tone generator for synthesizing tones by using a number of time-division multiplexed (TDM) modules, an input unit for programming a connection configuration (tone synthesis algorithm) for the modules of each module pair, and a processing unit for converting the input program into control data for each module and transferring the control data to the tone generator. In one embodiment, each module pair is selectively operative in an addition mode, a phase mode or a ring modulation mode, independently of the modes selected for the other module pairs. It is thus possible to attain a tone synthesis desired by the user, and to make the best use of the capacity of the tone generator. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation-in-part of U.S. application Ser. No. 11/187,724, filed on Jul. 22, 2005, the disclosure of which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] This invention relates to a setting time indicator for acrylic bone cement. More particularly the acrylic bone cement of the invention indicates its setting point in situ by a change in its color, which change can be visually recognized.
[0003] Bone cements find wide usage in a variety of applications. For instance, they are used for cementing orthopedic implants in place, for the anchoring of endoprosthesis of the joints, for filling voids in bone, in the treatment of skull defects, and for the performance of spinal fusion. These cements are typically polymeric materials and more particularly acrylic polymers and the surgeon usually mixes the interactive components to make the cement at an appropriate stage during the surgical procedure.
[0004] Typically, the components of the bone cement comprise a powdered homopolymer or copolymer of methyl methacrylates, alkyl methacrylates and/or styrene and a suitable liquid monomer. The liquid monomer consists of esters of acrylic or methacrylic acid for example methyl methacrylate. The liquid monomer is typically provided in a glass ampoule. To accelerate the polymerization of the bone cement, a catalyst system may also be used. The catalyst, if present, is in the form of a redox catalyst system, usually containing an organic peroxy compound, such as dibenzoyl peroxide, plus a reducing component, such as p-toluidine. N, N-dimethylparatoluidine (DMPT) can also be used as a polymerization accelerator and hydroquinone (HQ) can be used as a stabilizer. The DMPT and HQ may be included with the liquid monomer. A radiopacifier such as barium sulphate may also be included.
[0005] After the bone is prepared the liquid and powdered components of the bone cement are mixed. The setting time is one of the most important characteristics of acrylic bone cement. The setting time is the point after mixing at which the cement is hardened. Although all bone cement manufacturers indicate the setting profile in their product inserts, the actual setting properties in an operating room (OR) may vary significantly due to different environmental conditions such as temperature, storage conditions and mixing methods. Therefore, it is sometimes difficult for cement users to predict when the cement sets in situ.
[0006] Surgeons or nurses have sometimes used excess cement to determine the setting point of the implanted cement by placing the cement on a surface in the OR or by holding it in their hands. The OR personnel use the time when the excess cement gets warm and hard to determine the setting point of the implanted cement. This assumes that the implanted cement behaves the same as the excess cement. Because of the different environmental factors, the setting time of the “bench” cement may be significantly different to that of the implanted cement. While it may be possible to determine the setting point in situ by monitoring the temperature rise of cemented implants during a cement setting process, such is difficult and inaccurate. It would be advantageous to have an acrylic bone cement available which indicates its setting point in situ.
[0007] One advantage for surgeons is that the recognition of the setting point of bone cement in situ prevents early loading of the joint, which may cause migration of implants. It may also eliminate unnecessary surgical site exposure time should the surgeon overestimate the setting time. Therefore, development of a cement that is able to indicate its setting point in situ would benefit both bone cement users and patients. In addition colored cements may help surgeons easily distinguish the bone cement from the surrounding tissues especially during revision surgery.
[0008] The setting process of acrylic bone cement is a free-radical polymerization reaction of methyl methacrylate (MMA) monomer. The bone cement sets when most of MMA monomer is converted to polymethyl methacrylate (PMMA) polymer through free-radical polymerization. By monitoring the free-radical polymerization of MMA monomer, one can determine the setting point of bone cement. Based on this rationale, the cement of the present invention uses color change to visually indicate the setting point in situ and also leaves a colored cement for visual identification.
[0009] Two color pigments, β-carotene (pro-vitamin A) and FDC blue No. 2 Lake, were used to formulate this colored cement. Carotene is a natural product that exist in plant and fruits and is a major source of Vitamin A. As an orange-red powder, it is soluble in organic solvents such as methyl methacrylate and gives a yellow-orange color. Carotene belongs to the category “exempt from certification” classified by FDA and is widely used in food industry as GRAS (Generally Regarded as Safe).
[0010] FDC blue No. 2 Aluminum Lake is a color additive that has been approved for use in acrylic bone cement in an amount of up to 0.1% (w/w). Methylene blue powder also may be used as we as chlophyl which changes from light. It is insoluble in most solvents including water and methyl methacrylate. It has a good thermal stability and has been used in commercial bone cement products. It is supplied as a fine powder from Sensient Inc. of St. Louis.
[0011] As discussed above, acrylic bone cements are made from combining a powder polymeric component and a liquid monomer component and a polymerization initiator. One well known system is manufactured and sold by Howmedica Osteonics Corp. as Simplex® P bone cement. Heretofore, none of these types of systems have used color to indicate setting time.
[0012] U.S. Pat. No. 6,017,983 (Gilleo) relates to the use of a diazo dye that is believed to form a salt or complex with acid anhydrides, which acts as a color indicator for particular anhydride/epoxy resin thermoset adhesives. The resulting salt or complex is reported to produce a chromophoric shift in the dye which is indicative of the amount of acid anhydride present, and hence, the degree of cure. As the epoxy resin cures, the amount of acid anhydride diminishes, thus, producing a color change. This system appears to be limited to acid anhydride hardeners used to cure epoxy resins.
[0013] U.S. Publication No. 2003/0139488 (Wojciok) relates to a (meth) acrylate composition comprising a (meth) acrylate component; and a dye substantially dissolved in the (meth) acrylate component which imparts a first color to the (meth) acrylate component, wherein upon curing, a resultant cured composition has a second color. Preferably, upon curing, the resultant cured composition is substantially free of the first color.
SUMMARY OF THE INVENTION
[0014] It is one aspect of the present invention to provide a color indicator for setting time of an acrylic bone cement. In the preferred color indicator cement, a natural product called beta-carotene (Pro-vitamin A) is the compound which colors vegetables yellow or orange and is used as a pigment. This Pro-vitamin A is a well-known free radical scavenger and antioxidant. The Pro-vitamin A used herein is obtained from Aldrich Chemical Company. The basic structure of beta-carotene is made up of isoprene units. Its carbon-carbon conjugation system is eventually attacked by a free radical to lose its C—C conjugation during the bone cement setting process, resulting in its color change. Since only a small amount of Pro-vitamin A would be present in bone cement, the Pro-vitamin would participate in the free radical reaction only when most of MMA is consumed. Since the color change is caused by radical reactions of the isoprene units of the chemicals, the chemicals consisting of isoprene units that are susceptible to free radicals could be used in this application as a color indicator. For example, the compounds in a family of carotenoids such as lycopene and zeaxanthin could be candidates for color indicators for acrylic bone cements. These compounds have a lot of isoprene units and are well-known radical scavenges.
[0015] The invention relates to a bone cement which indicates its setting time via change in color and leaves a colored cement easily distinguishable from bone tissue. The bone cement comprises a liquid acrylic monomer component and a powdered acrylic polymer component, a polymerization accelerator and a first color additive, preferably yellowish beta-carotene, mixed into at least one of the liquid or powder components prior to or concurrently with its mixing. Between 5 and 500 ppm of the beta-carotene (0.0005% to 0.05% w/w) is preferably mixed into a liquid or powdered components. Of course, the beta-carotene could be mixed into both the liquid and powdered components. Preferably the liquid monomer comprises methylmethacrylate and the powdered component comprises a methylmethacrylate polymer. The liquid component comprises a monomer of an acrylic ester which when mixed with the beta-carotene and combined with FDC blue No. 2 Lake dye powder in the polymer powder forms a greenish color prior to setting and through free radical attack the beta-carotene loses its carbon-carbon bonds resulting in the color change from greenish to bluish.
[0016] A method for determining the setting time of an acrylic bone cement is also disclosed which includes mixing a liquid acrylic bone cement precursor and a powdered acrylic bone cement precursor having a blue dye therein with an additional yellow color additive, preferably beta-carotene. The color additives impart a first color to the bone cement (greenish). The beta-carotene color additive has carbon-carbon double bonds which break during polymerization causing a color change in the additive and consequently a bone cement having a different color than its initial color. Other carotenoids may also be used. In addition, other compounds that have carbon-carbon double bonds which are attacked by free radicals during polymerization causing the compound to lose or change color can be utilized. Since the blue dye does not undergo this change the final color of the cement is bluish.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIG. 1 shows a comparison of 50, 25 and 5 ppm mixtures of beta-carotene (Pro-vitamin A) in Simplex® P Mixed Bone Cement with the sample on the left hand side showing the bone cement prior to setting and the sample on the right hand side showing the sample after setting;
[0018] FIG. 2 shows the yellowness index versus time of the samples of FIG. 1 ;
[0019] FIG. 3 shows the whiteness index verses time of the samples of FIG. 1 ; and
[0020] FIG. 4 shows the color change of two non-Simplex® P Bone Cements both before and after setting.
[0021] FIG. 5 shows images of before and after setting of colored cements having FDC blue No. 2 aluminum Lake 0.05% and 0.025% and beta-carotene 500 and 250 PPM.
[0022] FIG. 6 shows two plots of the whiteness and yellowness index of two cement formulations during setting.
DETAILED DESCRIPTION
[0023] Pro-vitamin A is a natural product that exists in plants and fruits, which are a major source of Vitamin A. It belongs to the category of “exempt from certification” classified by FDA and widely used in food industry as GRAS (Generally Regarded as Safe). Pro-vitamin is a yellow-orange fine powder that is soluble in many organic solvents such as methyl methacrylate. It can also be easily dispersed into bone cement powder.
EXAMPLE 1
[0024] The color indicator cement (color cement) was prepared based on the formulation of Simplex® P bone cement. The color pigment can be either added in the Simplex® liquid monomer or dispersed in Simplex® cement powder. Alternatively, the color additive could be added by the surgeon on site as a separate component when he mixes either two components.
[0025] Pro-vitamin A is highly soluble in the Simplex® monomer (MMA) liquid component. Solid Pro-vitamin was directly added in Simplex® P liquid monomer, which turns the MMA monomer to yellow-orange. Pro-vitamin in an amount up to 50 ppm in Simplex P liquid component was examined in terms of color change and its effect on the setting properties of Simplex P bone cement. Formulations of the liquid component of color cements tested in this study are listed in Table 1. To get a 50 ppm mixture about 12 mg of beta-carotene was added to 200 ml of monomer, for a weight percent of 0.0062% w/w. The powder component of the color cement is the same as the standard Simplex® P powder described above.
TABLE 1 formulation of the liquid component Ingredients MMA DMPT (weight (weight Cement percent) percent) HQ Pro-vitamin A 97 2.6% 75 ppm 50 ppm B 97 2.6% 75 ppm 25 ppm C 97 2.6% 75 ppm 5 ppm
[0026] The color indicator cement was examined at room temperature in terms of its color change. The cement was mixed in a mixing bowl following the Simplex® bone cement mixing instructions. The color of the cement before and after set was recorded and shown in FIG. 1 .
[0027] FIG. 1 shows the results of color profiling of the before and after setting. The images show clearly that the color cement turned to yellow at the onset of contact of the powder with the liquid component. When the bone cement set, the yellow color was gone. As the amount of Pro-vitamin A increases from 5 to about 50 ppm, the color of the cement paste got more intense and color change was more significant. It was also found that disappearance of color occurred in a short time period (less than 60 seconds). 100 ppm Pro-vitamin concentrations or even higher could be used as long as setting times are not unduly extended or physical cement properties are not greatly degraded. Mixing methods such as hand mixing and vacuum mixing did not affect the color change of the cement.
[0028] Color change of the Pro-vitamin cement A was also measured by a spectrophotometer according to ASTM E313. Yellowness and whiteness index were recorded during the setting process, which are plotted versus time as shown in FIGS. 2 and 3 . Both color indexes changed dramatically in a short time period that closely matched the clinical setting time test used by cement surgeons in the operating room. In this method a stopwatch was started at the onset of contact of the liquid monomer to the powder. The mixture is mixed at a clinical relevant temperature (usually 65° F. or 18.5° C.) and the resulting acrylic bone cement paste is held on a hand. The cement on a hand is occasionally kneaded until it gets hot. When it hardens enough to be knocked against a hard surface (wall or tables), it indicates that the cement reaches its setting point. The time at this point is the setting time of the cement. The results also show that the cement with 25 ppm and 50 ppm Pro-vitamin A changed its color more significantly than that with 5 ppm Pro-vitamin A.
[0029] FIGS. 2 and 3 show yellowness and whiteness index respectively versus the setting process of the Pro-vitamin cement. YI: Yellowness index—the degree of departure of an object color from colorless or from a preferred white toward yellow; WI: whiteness index:—the degree of departure of an object color from that of a preferred white.
[0030] Setting time, dough time and maximum temperature of the color cements were determined following the ASTM standard methods described in ASTM F451-95 and are shown in Table 2. The results demonstrated that Pro-vitamin A up to 50 ppm in Simplex® bone cement liquid component has no effect on the dough time, setting time and maximum temperature of Simplex® P bone cement.
TABLE 2 Setting properties of color indicator cement Setting Properties Color indicator Dough Setting Tmax cement (minutes) (minutes) (° C.) A 3.00 11.86 80.3 B 3.00 11.21 73.3 Control 3.00 11.84 79.4 (No beta- carotene)
[0031] Further examples were carried out to determine if the time at the disappearance of color matches the setting time of the bone cement. Both the standard ASTM method and clinical setting time method “knock” i.e. were examined. The results showed that the time when the yellow color disappeared closely matched the “knock” setting time, although it was approximately 30 seconds later than ASTM setting time.
EXAMPLE 2
[0032] Pro-vitamin A in Simplex® powder component was also tested in terms of the color change and setting properties. 50 ppm (about 2 mg) Pro-vitamin A was added to 80 g and solid was directly blended with Simplex® P powder. The mixture was shaken for about 20 minutes in a shaker-mixture. The bone cement powder containing Pro-vitamin 50 ppm was evaluated. Since the amount of Pro-vitamin A was small, it did not change the appearance of the bone cement powder. The yellow color appeared during the mixing of liquid monomer with the powder component, and disappeared or faded when the cement set. The Pro-vitamin A in the powder component behaved similar as in the liquid monomer in terms of its color change and effect of on the setting properties of the bone cement. Setting time, dough time and maximum temperatures are shown in FIG. 3 .
TABLE 3 Setting properties of color indicator cement Setting Properties Color indicator Dough Setting Tmax cement (minutes) (minutes) (° C.) A 3.00 12.5 67.5
EXAMPLE 3
[0033] Pro-vitamin A was also tested for its color change in other bone cements including Biomet Palacos ® R bone cement and DePuy® 1 bone cement. FIG. 4 shows the color change of Palacos® R and DePuy ® 1 bone cements before and after cement set. Since Palacos ® R is green, at least 50 ppm (preferably 100 ppm) Pro-vitamin A was required to demonstrate its color change. The colorant could be added to either liquid or blended in powder component. Pro-vitamin A up to 100 ppm did not show any effects on the setting properties of the cements.
[0034] Beta-carotene was added into a liquid monomer of both DePuy ® 1 (25 ppm) and Palacos ® R (100 ppm). The powdered components were then mixed with the monomer at room temperature. The cement pastes became yellow at mixing but changed to their original colors without the use of beta-carotene on setting.
[0035] FIG. 4 . Color change of the cements before and after setting: up: DePuy 1 (approximately 25 ppm); low: Palacos R (approximately 100 ppm).
[0036] These examples demonstrated that Pro-vitamin (beta-carotene) can color acrylic bone cement by adding it either in the bone cement liquid component or dispersing it into the powder component. The formed color during mixing of the bone cement disappeared at the time when bone cement set, which visually indicated the setting point of the cement. This invention can be used in other powder-liquid acrylic bone cements such as Palacos® R, and DePuy® cements.
EXAMPLE 4
[0037] Simplex P bone cement was used for preparation of the colored cement. The powder component of the colored cement was formulated by blending the blue color and powder with Simplex P powder. The formed powder became light blue. In this study, up to 0.05% (w/w) FDC blue No. 2 Lake was mixed in the powder and the powder was then sterilized via gamma irradiation at a production dose for commercial Simplex P bone cement.
[0038] The liquid component of the color cement was prepared by simply dissolving carotene powder in Simplex P monomer as discussed above. The liquid monomer solution became orange. In this study, up to 500 ppm carotene in the monomer was investigated. The powdered components were blended until the color was consistent.
[0039] Single dose of the powder component (40 grams) was mixed with 20 ml of the monomer containing carotene following the manufacturer's instruction for Simplex P bone cement. Mixing was conducted at room temperature (21° C.). In this example, the powder contained 0.05% FDC No. 2 Lake and 500 ppm carotene was present in the monomer. After mixing, the cement paste became green, a combination of blue color and orange color. The green color turned to blue at the time when the cement set. FIG. 5 shows the color of the cement before and after setting. Vacuum mixing was also tested and was found not to have an effect on the colored cement in terms of its color change.
[0040] Carotene pigment can also be blended in the Simplex P powder component. 10 mg carotene solid powder (equivalent to 500 ppm in liquid) was directly blended with 40 g Simplex P powder containing 0.05% FDC blue No. 2 Lake in a cement mixer (Mixevac III, Stryker Co). Since the amount of pro-vitamin A was small, it did not change the appearance of the light blue bone cement powder. The green color appeared during the mixing of liquid monomer with the powder component, and it turned to blue when the cement set. Adding the Carotene to the powder or the monomer component had a similar effect on color change.
[0041] The setting process of acrylic bone cement is a free-radical polymerization reaction of MMA monomer. The bone cement sets when most of the MMA monomer is converted to PMMA polymer through free-radical polymerization.
[0042] The colored cement described in this invention, changes its color due to loss of the color from the carotene pigment during the setting process. Carotene molecules consist of a conjugated carbon-carbon double bond system as its chromophore. This conjugation system is susceptible to free radicals especially oxidation radicals. The chemistry of the color change in the color cement may be more complicated since there are probably carbon and peroxide radicals involved in the polymerization process. In general, the radicals generated during the bone cement setting process may react with the C=C conjugation system in carotene, resulting in breaking down of the conjugation system. Since a small amount of carotene is present in bone cement as compared to MMA monomore, it is anticipated that the carotene would participate in the reaction when most of the MMA is consumed. This explains that the color change occurs at the time when the cement gets hard i.e. when most of the MMA monomer is consumed.
[0043] Due to the loss of the color from carotene, the balance of the combined color shifts to the blue that is contributed by FDC No. 2 Lake. Either the initial color or the final color of the colored cement could be easily modified by altering the initial ratio of FDC blue No. 2 Lake and Carotene added to the cement.
[0044] Any colorants that undergo similar reaction may be considered as a candidate of a possible color indicator.
[0045] Color change of the colored cement was measured by a spectrophotometer according to ASTM E313. Two formulations were tested in this study. The whiteness and yellowness index were recorded during the setting process of the colored cement. These are plotted in FIG. 6 .
[0046] Formula 1: 0.05% FDC blue No. 2 Lake in powder; 500 ppm carotene in the liquid monomer.
[0047] Formula 2: 0.025% FDC blue No. 2 Lake in powder; 250 ppm carotene in liquid monomer.
[0048] FIG. 6 shows the yellowness and whiteness index versus the setting process of the colored cement. YI: Yellowness Index—the degree of departure of an object color from colorless or from a preferred white toward yellow; WI: Whiteness Index—the degree of departure of an object color from that of a preferred white.
[0049] Yellowness index changed dramatically in a short time period that closely matched the setting time of the cement. Whiteness index was not sensitive to the change of color because the cement changed its color from green to blue.
[0050] A study was conducted to determine the effect of the color pigments on setting properties of the cement. The colored cement containing 0.05% (w/w) FDC blue No. 2 Lake in the powder component and 500 ppm carotene in the liquid component was tested in comparison with the same batch of Simplex P without color pigment. Setting time, dough time and maximum temperature of the colored cements were determined following the ASTM standard methods described in ASTM F451-95 and are shown in table 4. The experiment was conducted at environmental control room at 20° C., 50% RH. It was found that the colored cement containing up to 500 ppm carotene has no effect on the dough time and setting time
[0051] It was also noted that change in color for the colored cement occurred just right at the time when the temperature of the color cement dramatically rose.
TABLE 4 Setting properties of color cement Setting properties (n = 2) Dough Setting Tmax Cement Carotene (min) (min) (° C.) Color cement 1 500 ppm 4.3 15.7 67.7 Color cement 2 250 ppm 4.2 15.2 70.5 Control cement 4.4 15.7 73.2
[0052] Although the invention herein has been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present invention. It is therefore to be understood that numerous modifications may be made to the illustrative embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended claims. | A bone cement has a liquid acrylic monomer component, a powdered acrylic polymer component and yellowish beta-carotene (Pro-vitamin A) mixed into one of the liquid or powdered component and FDC blue No. 2 Lake powder mixed into the powdered component. The beta-carotene and FDC blue adds a greenish (yellow plus blue) color to the combined liquid and powdered component. The yellowish color disappears on setting of the bone cement leaving the cement blue. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to tone transmission in test call generation systems and more particularly to the automatic sending of coded tones in a particular one of several codes in order to transmit the digits comprising a telephone directory number.
2. Description of the Prior Art
In the transmission of telephone directory numbers between switching centers and between a subscriber and a switching center the use of multiple-frequency (MF) signaling and touch calling multiple-frequency signaling (TCMF) respectively, is well known. These signaling schemes employ the use of coded tone signals for the transmission of digits comprising the directory number. A collection of predetermined frequencies forms the basis for each of these signaling codes. Multiplefrequency (MF) signaling selects two out of a group of six frequencies for transmission to form a given digit, whereas touch calling multiple-frequency (TCMF) depends upon the selection of two of eight frequencies for transmission to form a particular digit comprised of a telephone directory number.
Historically, these tone codes have been generated by separate circuits in a telephone office. Heretofore, the technology employed has embodied the use of LC oscillators for the generation of these tones in call initiation systems. Such systems have utilized separate circuits for the generation of these tone frequencies. The use of separate tone generation equipment necessitates the use of separate control logic for the application of these tone signals. Such systems are necessarily complex and require extensive maintenance. In addition, these systems present a multiplicity of design problems and prohibit subsystem modularity.
U.S. Pat. No. 3,719,897 issued on Mar. 6, 1973, to L. A. Tarr, depicts a system in which a tone generator system is used to diagnose tone receiving equipment in a telephone office. In the Tarr patent a single input signal selects a single frequency of either MF or TCMF. Although in the Tarr patent the use of a crystal controlled clock is disclosed, only a single frequency of the two necessary for digit identification is generated.
Therefore, it is an objective of the present invention to provide a single source for the generation of digits comprising a telephone directory number in either the multi-frequency or touch calling multi-frequency codes. Such source provides for simulation of either line or trunk call originations and basic subsystem modularity for simple design.
SUMMARY OF THE INVENTION
The present invention consists of a tone sender system which provides in a single source the capability to originate telephone calls in either a multi-frequency (MF) or touch calling multi-frequency (TCMF) code. In each of these transmission codes, a combination of analog tone pairs is produced to represent a digit of a telephone number. Each of the tones comprising the telephone number digit is of a predetermined frequency. The tone sender described herein is connected to a telephone central office and generates simulated line or trunk originations depending upon the transmission code selected. This tone sender is designed to be controlled by digital signals applied by an appropriately timed telephone office central processor control system.
The control system consists of a central processor with memory. The central processor is connected to bistable latches via bi-directional bus. The bistable latches, in turn, are connected to the initial stage of the tone sender circuitry, the decode logic. The signals sent from the bistable latches to the decode logic comprise a binary coded decimal representation of a telephone digit to be transmitted. Four of such signals from the latches are required for this purpose. The bistable latches further provide an additional set of supervisory signals. These supervisory signals indicate to the tone sender system the particular transmission code in which the given digit is to be sent.
The decode logic provides isolation between the bistable latches and the tone sender circuitry. The signals from the bistable latches are decoded from their binary coded decimal form to a collection of binary signals each representing a particular telephone digit. In the MF signaling code, ten of these signals are required to represent the digits (0 through 9) comprising a telephone number and the remaining six of these signals are used for various supervisory signaling purposes; whereas, in the TCMF transmission code twelve of these signals are required to represent the digits (0 through 9 and special functions * and #) leaving four signals remaining for supervisory signaling purposes.
These signals are then encoded into a pair of signals in each transmission code (MF and TCMF) which represent the digit to be sent. The pair of signals thereby produced for each transmission code represents the tone frequencies associated with the given digit in that particular code, with each signal representing a particular predefined frequency. For example, the digit 0 is represented by the frequencies 1300 Hz and 1500 Hz in MF and by the frequencies 941 Hz and 1336 Hz in TCMF.
The supervisory signals supplied by the bistable latches are utilized to gate the signals representing the given digit in the selected transmission code into a frequency encode network for subsequent processing. Next, the selected pair of digit representative signals is further encoded into two sets of signals, representing the time periods of corresponding frequencies which comprise the given digit. These time period representation signals are applied to two independent counting chains along with an input signal from a 1 MHz crystal controlled clock. The clock provides a constant source of pulses; one pulse per microsecond. Each of the two counting chains produces one of the tone frequency signals comprising the given digit. The frequency signals so produced are in the form of square waves of the desired frequencies.
Lastly, these two resultant square waves are combined and converted into a single sine wave of the appropriate frequency by filtering out any undesirable frequency components. The combined output signal is amplified and now is suitable for coupling to a transmission line. This output frequency signal remains present at the output as long as the bistable latches are controlled to provide the signals to the tone sender system. Under control of the central processor, the bistable latches preserve their present signal statuses for a predetermined time period of approximately 60 ms.
Upon expiration of the above mentioned time interval, the central processor resets the bistable latches thereby creating an absence of the output frequency signal of the tone sender system. Similar to the signal application interval, a signal absence interval is timed for a period of approximately 60 ms. As a result, a pulse of tone is produced which represents the given telephone digit in the appropriate transmission code.
The complete initiation of a line or trunk call origination includes a cyclic repetition of the above process for each of the digits comprising a telephone number. In order to initiate a line origination the TCMF transmission code is utilized and in order to initiate a trunk origination the MF code is employed. The present tone sender system, although embodying TCMF and MF codes, is easily adaptable to send other tone signaling codes.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of a multiple tone code sender system in accordance with the present invention.
FIG. 2 is a schematic circuit diagram of a decode logic circuit in the present invention.
FIG. 3 is a schematic circuit diagram of a frequency encode network for the transmission of representative frequency signals in the present invention.
FIGS. 4 and 5, taken in combination, are schematic circuit diagrams of an encoding circuit for selection of time period representative signals of MF and TCMF frequencies in the present invention. FIGS. 4 and 5 represent schematic diagrams for MF and TCMF low frequencies and MF and TCMF high frequencies respectively.
FIG. 6 is a schematic circuit diagram of twin frequency divider circuits for production of frequency signals in the present invention.
FIG. 7 is a schematic circuit diagram of a mixer, low pass filter and associated amplifier in the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In FIG. 1, a block diagram of a multiple code tone sender system is shown in accordance with the present invention. The multiple tone code sender includes decode logic 100 connected to a central processor unit via a bank of bistable latching devices (not shown). The decode logic provides isolation between the remainder of the tone sender circuitry and the bistable latching devices. The central processor sends, via the latches a telephone digit to be transmitted. Input signals DB1 through DB8 which represent the digit in binary coded decimal form are decoded to form signals digit 1 through digit 16 at the output of decode logic 100.
Signals digit 1 through digit 16 are combined and coded by frequency encode network 200 to produce four groups of signals, each signal is representative of a predetermined frequency associated with each transmission code (MF and TCMF). Two frequency groups are associated with each transmission code. One frequency in each of the following groups is produced for a given digit: MF low frequency, MF high frequency, TCMF low frequency, and TCMF high frequency. Each of these frequency groups comprises a collection of predetermined frequencies. One frequency in each of the four groups is selected by the application of the telephone digit from the central processor unit.
Signals TCEN and MFEN determine which two of the four frequency groups are permitted to be processed further by high-low frequency elect network 300. High-low frequency select network 300 processes the selected two groups of frequency representative signals in the selected transmission code. These signal groups are each further coded to produce signals representing the time periods associated with each of the two selected frequencies representing the digit.
Each set of time period representative signals is respectively applied to a corresponding frequency divider 400 and 600. Furthermore, a signal from the 1 MHz crystal controlled clock 500 is applied to each frequency divider. As a result of the application of the combination of these signals, low frequency divider 400 and high frequency divider 600 produce low frequency and high frequency square waves, respectively.
These resultant square waves are applied to mixer 700, whereby a single output signal is produced representing the sum in sine wave form of the input square wave frequencies. This is accomplished by filtering out any undesirable frequency components via low pass filter 800. This combined signal is amplified through amplifier 900 and produces an output suitable to be coupled to the transmission line.
The central processor unit applies signals DB1 through DB8 and TCEN and MFEN to the bistable latches for a predetermined time period approximating 60 ms. Upon expiration of this time period a like time period of 60 ms. is timed during which the bistable latches are reset thereby producing an absence of any tone frequency signal output from the tone sender system. As a result, a pulse of tone is produced which represents in coded form the given digit to be transmitted. The complete initiation of a telephone call origination includes a repetition of the described process, thereby producing a series of tone pulses which collectively represent the telephone number to be transmitted.
Now referring to FIGS. 2 and 3, taken in combination with FIG. 2 to the left of FIG. 3, input signals DB1 through DB8 and supervisory signals TCEN and MFEN are applied to optical-couplers 110 through 115 respectively, thereby producing representative signals which are isolated from the latching circuitry. The signals thereby produced are inverted via inverters 124 through 127. The output signals of the inverters 124 through 127 are applied to the BCD to binary decoders 130 and 140. Each BCD to binary decoding device generates eight output signals. Each of these outputs indicates either a logic "0" of logic "1" state. The signals comprising the frequencies of the digit are marked by a logic "1", all other signals are marked by a logic "0".
These binary outputs are interconnected by encoding gates 210-216, 220-226, 230-233 and 240-243 to generate signals each representative of a frequency associated with one of the transmission codes. This encoding structure includes a plurality of NOR gates and inverting gates. The output signals at gates 212 through 216 and 222 through 226 represent the frequencies associated with the given digit in the multi-frequency code and the output signals at gates 230 through 233 and 240 through 243 represent the frequencies associated with the given digit in the touch calling multi-frequency code.
These representative frequency signals are combined with the enabling signals output by gates 121 and 123. The output signals of gates 121 and 123 represent the multi-frequency and touch calling multi-frequency enable signals respectively. The MF enabling signal produced by gate 121 is combined with the MF representative frequency signals at gates 250-254 and 260-264. The touch calling enable signal produced at gate 123 is combined with the TCMF representative frequency signals at gates 270-273 and 280-283. Via control of the supervisory signals of gates 121 and 123, the frequency representative signals of either the MF or the TCMF code are gated through for subsequent processing.
As shown in FIGS. 4 and 5, each of the frequency representative signals comprising the digit in the selected code is further encoded to produce a set of signals representative of the time periods associated with each of the frequencies comprising the digit. The low frequency of the selected transmission code is encoded by gates 310-315 and 300-339; whereas, the high frequency representative signals are encoded by gates 320-325 and 340-349 to produce the time period signals.
Referring now to FIG. 6, each set of time period signals is applied to the appropriate frequency divider. Also applied to each frequency divider is a signal from the 1 MHz clock 500. Each frequency divider network 400 and 600 includes three programmable divide by N 4-bit counters. These programmable divide by N counters are of a standard commercially available type. The low frequency time period signals are applied to divider 400 and the high frequency time period signals are applied to divider 600. The high and low dividers each produce a single output signal H and L respectively.
As indicated in FIG. 7, signals H and L, the high and low frequency signals respectively, are applied to flip-flop device 710 thereby producing square waves of the appropriate frequencies. The flip-flop device 710 is conventional and does not form a portion of the present invention. The flip-flop output signals are respectively applied to resistors 720 and 730. The output signals of these resistors are added together by directly connecting the two signals produced by the resistors. The signal thereby produced is applied to amplifier 750. The output signal of amplifier 750 is applied to low pass filter 800 thereby producing a single signal representative of the two predetermined frequencies which comprise a given digit. This signal is applied to amplifier 900 which includes transistors 910, 930 and 940 to produce a suitable signal for coupling to the transmission network.
Although a preferred embodiment of the invention has been illustrated, and that form described in detail, it will be readily apparent to those skilled in the art that various modifications may be made therein without departing from the spirit of the invention or from the scope of the appended claims. | A tone sender system for producing analog tone pairs for transmission of the digits comprising a telephone number. Dual codes, multi-frequency and touch calling multi-frequency, are produced to generate simulated test call originations. This tone sender system provides in a single source the capability to generate telephone call originations requiring either multi-frequency (MF) or touch calling multi-frequency (TCMF) tone pairs for the digit transmission. The tone code to be utilized is selectable. | 7 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The invention relates to a building construction method for controlling attic moisture and improving the energy efficiency of a building by the installation of a breathable membrane in order to seal the attic space and provide an active air space between the attic and the roof deck.
[0003] 2. Description of the Prior Art
[0004] In conventional building practices for construction of buildings having an attic space above the useful living space and below the roof, particularly buildings using wooden rafters and/or decking below the roof, the moisture level in the attic is typically controlled by ventilating the attic with air flow from the eaves of the building to the ridge vent at the highest point of the roof. As shown in FIG. 1 , air is allowed to flow by means of convection from open spaces along the eaves (between the walls of the building and the bottom of the roof line) to the open space along the ridge(s) at the top of the roof, i.e., the ridge vent. This flow of air purges the attic of moisture before it can build up in the attic 2 . Moisture commonly enters the attic from the living space in the form of vapor. Sources of moisture in the living space include human respiration, use of bathtubs and showers, cooking, houseplants, etc.
[0005] Typically, the attic 2 is open to the flow of air from the living space and from the exterior of the building surrounding the eaves. While this allows for good moisture control in the attic, it is often not energy-efficient since the living space 4 is not sealed and energy from the climate-controlled living space is permitted to leak to the exterior of the building through the ridge vent with the airflow.
[0006] Expandable foams have been used to insulate and seal the attic. The foams are sprayed under the roof decking and inside the roof rafters, or on the “floor” of the attic. While this can effectively seal the attic, this method does not prevent moisture from building up in the attic since the foams used are typically not breathable and do not permit air to flow through the attic, therefore this is not acceptable for many climates.
[0007] It would be desirable to provide a construction method that eliminates the exchange of air between the living space and the attic thereby providing good overall energy efficiency of the building, and that provides good control of moisture in the attic.
SUMMARY OF THE INVENTION
[0008] This invention is a method for controlling attic moisture and improving the energy efficiency of a building comprising peripheral walls and a roof comprising rafters having a ridge vent at the highest portion of the roof and eaves at the lowest portion of the roof, the method comprising:
[0009] installing a breathable membrane over the rafters,
[0010] sealing the breathable membrane to the peripheral building wrap,
[0011] installing a roof deck over the rafters, and
[0012] providing an air space between the breathable membrane and the roof deck wherein the air space is open to the exterior of the building at the eaves and at the ridge vent of the building such that air is permitted to flow freely between the eaves and the ridge vent.
[0013] This invention is also the breathable membrane.
DEFINITIONS
[0014] The term “active air space” refers to an air space in which air is allowed to freely move both within the air space and in and out of the air space in response to conditions that influence air flow, e.g., thermal gradients.
[0015] The term “roof deck” is used interchangeably with the term “roof decking” and refers to the structural board on which roofing material (e.g., shingles) is installed, such as plywood or oriented strand board (OSB).
[0016] The term “eave” herein refers generally to the intersection between the roof and the wall of a building.
[0017] The term “ridge vent” herein refers generally to the space between differing planes of roof decking along their uppermost edges, typically protected by a cap.
[0018] The term “hip” herein refers to the intersection of multiple planes of roofing wherein the line or point of intersection is at the highest point relative to the height of the intersecting planes of roofing.
[0019] The term “valley” herein refers to the intersection of multiple planes of roofing wherein the line or point of intersection is at the lowest point relative to the height of the intersecting planes of roofing.
[0020] The term “peripheral building wrap” herein refers to the use of a flexible sheet material to wrap the unfinished walls of a building, such as a weather-resistive barrier.
[0021] The term “rafters” is used herein to refer to discrete structural load-bearing elements which form the upper portion of a building's attic (also commonly referred to as joists, beams, or trusses).
[0022] The term “counter battens” refers herein to elongated strips used in the installation of roofs, typically installed directly over the roofing trusses or rafters, each counter batten extending the length of the truss or rafter.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] FIG. 1 (prior art) is a cross-sectional view of a house illustrating conventional residential construction.
[0024] FIG. 2 is a cross-sectional view of a house having a breathable membrane installed such that an active air space is provided between the membrane and the roof decking, and the attic is sealed, according to the present invention.
[0025] FIG. 3A is a cross-sectional view of a roof along the length of the roof rafters illustrating one method for installing the breathable membrane.
[0026] FIG. 3B is a cross-sectional view of a roof through the cross-section of the roof rafters illustrating the same method for installing the breathable membrane as shown in FIG. 3A .
[0027] FIG. 4A is a cross-sectional view of a roof along the length of the roof rafters illustrating one method for installing the breathable membrane.
[0028] FIG. 4B is a cross-sectional view of a roof through the cross-section of the roof rafters illustrating the same method for installing the breathable membrane as shown in FIG. 4A .
DETAILED DESCRIPTION OF THE INVENTION
[0029] The method of the invention provides an active air space directly below the roof deck for the active flow of air entering the air space at the eaves and exiting the building at the roof ridge. As shown in FIG. 2 , the active air space 6 is the space between breathable membrane 8 and roof deck 10 . The active air space 6 removes water vapor to avoid moisture building up in the wood of the rafters and roof deck. The method of the invention also seals the attic 2 , thereby minimizing air exchange between the living space 4 and the attic and providing considerable energy savings to the building owner. Some energy is still allowed to escape through the ridge vent, but less than in prior art construction methods.
[0030] In one embodiment of the invention, as shown in FIGS. 3A and 3B , a breathable membrane 8 is installed on top of the rafters 12 such that sufficient slack in the membrane drapes down between adjacent rafters to create an active air space 6 , i.e., the air gap between the membrane and the roof deck 10 between adjacent rafters. Preferably, the height of the air space, i.e., the distance between the roof deck and the membrane, is between about ½ inch (1.3 cm) and about 2 inches (5 cm). This method works well for simple roof designs such as straight, gabled roofs, having no hips or valleys. If this method is used on complex roof designs having hips and/or valleys, careful installation is required in order to provide a uniform air space.
[0031] In another embodiment of the present invention, as shown in FIGS. 4A and 4B , another method is used to create the active air space below the roof deck. A breathable membrane 8 is installed over the rafters 12 , tightly with no slack. Counter battens 14 are positioned directly over the membrane and above the rafters and fastened to the rafters through the membrane. The roof deck 10 is then installed above the counter battens. The height of the counter battens determines the distance between the roof deck and the membrane and therefore the height of the air space 6 below the roof deck. The counter battens are preferably about 0.5 inch (1.3 cm) to about 2 inches (5 cm) in height when installed wherein the distance between the roof deck and the membrane is sufficient to allow air to flow freely through the air space. This method works well with all roof types, including complex roof designs having hips and valleys.
[0032] In both of the embodiments described above, the attic is sealed around the perimeter of the building. The attic can be sealed by slitting the breathable membrane at the eave and taping it over the peripheral building wrap, or if no building wrap is used, by taping it to the exterior of the peripheral walls of the building. The breathable membrane seals the roof rafters to the exterior of the peripheral walls so that there is no open air gap between the attic and the exterior of the building. Sealing the attic in this way has been found to provide significant energy savings since the air flowing through the active air space between the membrane and the roof deck is primarily air which enters at the eaves, not air which is drawn from the attic or living space beneath the attic as occurs with conventional, unsealed attics.
[0033] In the embodiments described above, the breathable membrane is installed above the roofing rafters. The present inventor believes that the same benefits could be obtained if the breathable membrane were installed directly above the attic “floor,” however, because of conventional building practices in which wires, duct work, etc., are installed at this location, it is difficult and less desirable to seal the membrane at this location.
[0034] The breathable membrane can be any vapor permeable material, preferably having a moisture vapor transmission rate of at least about 20 US perms according to ASTM E96 Method A. The breathable membrane allows moisture to diffuse through it from the attic space into the active air space where moisture is carried by the flowing air to the exterior through the ridge vent. Preferably, the breathable membrane is durable and UV resistant. A preferred membrane has a tensile strength (according to ASTM test method D828) of at least about 34 lb/in (59 N/cm) in the machine direction and about 30 lb/in (52 N/cm) in the cross direction. More preferably, after exposure to 25 cycles of accelerated aging consisting of oven drying at 120° F. for 3 hours, immersion in water at room temperature for 3 hours and air-drying for 18 hours at room temperature (73° F.), the membrane does not lose strength. Also preferably, after exposure to UV radiation for 210 hours (10 hours/day for 21 days) with 5.0 Watts/m 2 irradiance at a wavelength of 315-400 nm, wherein the membrane is held at a distance of one meter from the UV source, at a membrane temperature of 140° F., the membrane does not lose strength and shows no visible signs of damage.
[0035] An example of a suitable breathable membrane is a two-layer composite sheet with Tyvek® HDPE (available from E. I. du Pont de Nemours and Company) as the inner layer and a durable spunbond polypropylene sheet as the outer layer. The composite sheet can be made by joining the two layers with an adhesive and subjecting them to a thermal calendering process. The temperature of the calendering process should be sufficient to melt the adhesive, and the nip pressure should be sufficient to force the molten adhesive around the fibers of the two layers to lock the two layers together mechanically and ensure high delamination strength of the composite sheet.
[0036] Other examples of materials suitable for use as the breathable membrane in the invention are spunbond polyolefin nonwoven sheets, including for instance a three-layer spunbonded polypropylene fabric such as the roofing underlayment sold under the trade name Roofshield® (available from the A. Proctor Group, Ltd., UK).
[0037] Other materials suitable for use as the breathable membrane are a nonwoven sheet comprising sheath-core bicomponent melt spun fibers, such as described in U.S. Pat. No. 5,885,909, herein incorporated by reference; and a composite sheet comprising multiple layers of sheath-core bicomponent melt spun fibers and side-by-side bicomponent meltblown fibers, such as described in U.S. Pat. Nos. 6,548,431, 6,797,655 and 6,831,025, herein incorporated by reference. For instance, the bicomponent melt spun fibers can have a sheath of polyethylene and a core of polyester. If a composite sheet comprising multiple layers is used, the bicomponent meltblown fibers can have a polyethylene component and a polyester component and be arranged side-by-side along the length thereof. Typically, the side-by-side and the sheath/core bicomponent fibers separate layers in the multiple layer arrangement.
EXAMPLES
[0038] Three residential construction sites located in Calgary, Alberta, and Prince Edward Island in Canada and Jackson, Wis. in the United States were identified for the installation of a breathable membrane according to the invention. In each house, the attic space was sealed with a DuPont Tyvek® Supro Style 2506 B breathable membrane having a basis weight of 150 g/m 2 and a moisture vapor transmission rate of 71.4 US Perms. An active air space was created above this installed membrane and below the roof deck.
[0039] In each of the three houses, the membrane was laid tightly over the top of the rafters. Wooden counter battens were then secured using nails and/or staples directly over and aligned with the rafters. In two of the three houses, the counter battens had cross-sectional dimensions of about 1⅝ in (4.13 cm) by about 1⅝ in (4.13 cm). In the other house, the counter battens had a height (perpendicular to the roof deck) of about 1⅝ in (4.13 cm) and a width (parallel to the roof deck) of about 3⅝ in (9.21 cm). The roof deck was attached over the counter battens. The counter battens created an active air space between the membrane and the decking. The counter batten was terminated about 1-2 inches (2.5-5 cm) away from the hip or valley to allow air flow to the ridge vent.
[0040] It was observed that no moisture accumulated in any of the attics of the three houses. Typically, all wooden members in the attic were inspected for mold, water, or evidence of moisture condensation. The breathable membrane was also inspected for evidence of condensation. In some cases, the breathable membrane was slit to look into the air space between the membrane and the roof deck for evidence of condensation. These inspections were typically held about 6 months after completion (in the winter months for the cold climate). | A building construction method for controlling moisture in a building attic and improving the energy efficiency of the building achieved by installing a breathable membrane directly above the roof rafters thereby providing the presence of an air gap between the breathable membrane and the roof deck and sealing the membrane to the peripheral walls of the building, such that energy that normally passes from the living space into the attic and out the top of the building is conserved. | 4 |
FIELD OF INVENTION
[0001] The present invention relates to a method for manufacturing a polymer product with super- or highly hydrophobic characteristics, preferably in the form of a film. Also methods for the manufacturing of a laminate and a polymer coated paper or board product, respectively, both having said characteristics, are disclosed.
[0002] The present invention also relates to products obtainable by said methods and uses thereof.
BACKGROUND
[0003] Superhydrophobicity as a phenomenon has been disclosed in “An introduction to superhydrophobicity” Neil J. Shirtcliffe et al, Advances in Colloid and Interface Science, 161 (2010) 124-138.
[0004] Superhydrophobic Polyolefin Surfaces are also disclosed in “Superhydrophobic Polyolefin Surfaces: Controlled Micro- and Nanostructures”, Esa Puukilainen et al, Langmuir, 2007, 23 (13), 7263-7268.
[0005] Further, self cleaning technologies are disclosed in “Self cleaning materials”, Peter Forbes, Scientific American, August, 2008, pp. 88-95.
[0006] Further production of corrugated cardboard is disclosed in FR2782291.
[0007] SE7512107 discloses a method of making paper-plastic laminates.
[0008] An image transfer belt with controlled surface topography to improve toner release is further disclosed in US2010/300604.
[0009] However none of-these documents discloses solutions how to
make it easy to empty dairy packages, reduce foaming during conveying soft drinks or beer into a cup or how to obtain a nice touch surface.
[0013] Accordingly there is a need for a solution solving one or more of the above problems.
SUMMARY OF THE INVENTION
[0014] The present invention solves one or more of the above problems, by providing according to a first aspect a method for manufacturing a polymer product with super- or highly hydrophobic characteristics, preferably in the form of a film, comprising the following step:
[0015] a) providing a polymer melt and contacting said polymer melt with a mould giving said polymer product a pattern providing a Lotus effect, and
[0016] b) optionally cooling the polymer product obtained (which is preferred).
[0017] The present invention also provides according to a second aspect a method for manufacturing a laminate comprising a polymer product with super- or highly hydrophobic characteristics, preferably in the form of a film, and a web of paper or board comprising the following step:
[0018] i) providing a polymer melt and contacting said polymer melt with a mould giving said polymer product a pattern providing a Lotus effect,
[0019] ii) optionally cooling the polymer product obtained, and
[0020] iii) providing a web of paper or board and laminating said polymer product to a web of paper or board.
[0021] The present invention also provides according to a third aspect a method for manufacturing a polymer coated paper or board product, wherein said product has super- or highly hydrophobic characteristics, comprising the following steps:
x) providing a melt of polymer and a web of paper or board, coating said web of paper/board with said melt of polymer, xi) passing said polymer coated web of paper or board over a roll whereby said roll faces the polymer coated side and wherein also said roll provides a mould giving said coated side a pattern providing a Lotus effect when in contact with said coated side of said composite, and xii) optionally cooling said product obtained (which is preferred).
[0025] The present invention also provides according to a fourth aspect a polymer product obtainable by the method according to the first aspect.
[0026] The present invention also provides according to a fifth aspect a laminate obtainable by the method according to the second aspect.
[0027] The present invention also provides according to a sixth aspect a polymer coated paper or board product obtainable by the method according to the third aspect.
[0028] The present invention also provides according to a seventh aspect use of a polymer product according to the first aspect, a laminate product according to the second aspect or a product according to the third aspect in food packages, preferably pouches, cups or beakers.
[0029] The present invention also provides according to an eighth aspect use of the laminate product according to the second aspect or a product according to the third aspect in liquid packaging board, preferably in food packages for containing beverages, dairy products (such as butter or other milk products), edible oil products (such as liquid margarine or vegetable oil), frozen food materials or dry food.
[0030] The present invention also provides according to a ninth aspect use of a polymer product according to the first aspect, a laminate product according to the second aspect or a product according to the third aspect in a disposable drinking cup.
[0031] The present invention also provides according to a ninth aspect use of a polymer product according to the first aspect, a laminate product according to the second aspect or a product according to the third aspect in a glue or tooth paste package.
[0032] The present invention also provides according to a tenth aspect use of a polymer product according to the first aspect, a laminate product according to the second aspect or a product according to the third aspect in a tray or plate.
[0033] The present invention also provides according to a eleventh aspect use of a polymer product according to the first aspect, a laminate product according to the second aspect or a product according to the third aspect in an autoclavable product package, preferably in a package autoclavable at a temperature of at least 115° C. The temperature in an autolave is typically in the range of 115-125° C. (tomato ext.) and for meat one may use 130° C.
[0034] The present invention also provides according to a twelfth aspect use of a polymer product according to the first aspect, a laminate product according to the second aspect or a product according to the third aspect, to control adhesion or friction, or control the thermal conductivity.
[0035] The present invention also provides according to a thirteenth aspect a packaging board comprising a fibrous base and one or more polymer coating layers on one or both sides of the fibrous base wherein one or both of the layers has super- or highly hydrophobic characteristics.
DETAILED DESCRIPTION OF THE INVENTION
[0036] It is intended throughout the present description that the expression “super- or highly hydrophobic characteristics” embraces that a Lotus effect® can be detected. This means that a reduced wettability is to be seen (such effect is e.g. know from leaves). Via the Young's equation the degree of wettability can be calculated. The degree of wetting is calculated by using the interfacial tension ratio of the materials. A complete wetting is indicated by a contact angle of 0° whereas complete unwettability is indicated by a contact angle of 180°. See also FIG. 1 showing a material with super- or highly hydrophobic characteristics.
[0037] It is intended throughout the present description that the expression “oleophobic wax” means a compound which enhances the lotus effect. In addition to the above meaning it also encompasses that it is repellant to water. Said compound may be selected from AKD or Calcium stearate, or combinations thereof.
[0038] According to a preferred embodiment of the second and third aspect of the invention the board is a board for use in liquid carton.
[0039] According to a preferred embodiment of the second and third aspect of the invention the board is a packaging board and the weight of the polymer coating is at least 14 g/m 2 .
[0040] According to a preferred embodiment of the second and third aspect of the invention the density of the fibrous board base is at least 575 kg/m 3 , more preferred at least 615 kg/m 3 and most preferred at least 650 kg/m 3 .
[0041] According to a preferred embodiment of the third aspect of the invention the roll is a cooling drum.
[0042] According to a preferred embodiment of the third aspect of the invention the roll has a mould essentially resembling a cup field.
[0043] According to a preferred embodiment of the first, second and third aspect of the invention the polymer is selected from the group comprising polyethylene (PE; which may e.g. be low density polyethylene—LDPE, linear low density polyethylene—LLDPE or high density polyethylene—HDPE, polypropylene (PP), ethylene vinyl alcohol (EVOH) or ethylene vinyl acetate (EVA) or a polyester such as polyethylene terephthalate (PET), polylactic acid (PLA), polyamide (PA; such as polyamide 6-PA6) or combinations thereof.
[0044] According to a preferred embodiment of the first, second and third aspect of the invention also an oleophobic wax is added on to the polymer.
[0045] According to a preferred embodiment of the first, second and third aspect of the invention, oil is added on top of the polymer, which preferably is PE, after moulding. This has the effect of making the surface totally slippery against e.g. yoghurt and such
[0046] The present invention also provides the possibility to have different colours like blue, gold and red. Further it also provides a positive touch effect.
[0047] Providing a polymer melt as set out in the first aspect of the invention may also be done so that the metal surface is heated (which melts the polymer indirectly).
[0048] The cooling step according to the first, second and third aspect may be passive (i.e. just let the cooling occur in room temperature) or active.
[0049] Preferred features of each aspect of the invention are as for each of the other aspects mutatis mutandis, The prior art documents mentioned herein are incorporated to the fullest extent permitted by law. The invention is further described in the following examples, together with the appended figures, which do not limit the scope of the invention in any way.
[0050] Embodiments of the present invention are described as mentioned in more detail with the aid of examples of embodiments, together with the appended figures, the only purpose of which is to illustrate the invention and are in no way intended to limit its extent.
FIGURES
[0051] FIG. 1 discloses a material with super- or highly hydrophobic characteristics (thus highlighting the Lotus effect®).
[0052] FIG. 2 discloses hydrophobic liquid package using Metal mould 1.
[0053] FIG. 3 discloses hydrophobic liquid package using Metal mould 2.
[0054] FIG. 4 discloses hydrophobic liquid package using Metal mould 3: 6 μm grooves cross direction, barrell lens f 25 .
[0055] FIG. 5 discloses hydrophobic liquid package using Metal mould 4: 6 μm grooves cross direction, barrel lens f 12 , 7 .
[0056] FIG. 6 discloses a material with a pattern comprising areas with higher squares.
[0057] FIG. 7 discloses a material with a pattern comprising areas with pins.
[0058] FIG. 8 discloses a material with a pattern comprising areas with linear bulges.
EXAMPLES
Example 1
[0059] Testing:
Moulded steel surface was formed with the help of laser The mould was pressed with PE-foil or Cupforma Dairy 2PE 20+255+35 (both encompass LDPEs) to achieve replica pattern on plastic and on liquid package board surface, respectively. Contact angles of liquid and surface were measured for:
Water Milk
[0065] 4 patterned metal surfaces were pressed with PE-foil or liquid package board to get patterned surfaces
[0066] Surfaces 1 and 3 had the highest contact angles as set out below
[0067] Contact angels °, with water and milk as set out below
[0000]
TABLE 1
results from the trials set out above
Ref.
Surface 1
Surface 2
Surface 3
Surface 4
PE-foil
water
83.1
104.6
100.2
96.8
97.7
milk
88.2
80.0
87.3
81.4
71.3
Cupforma Dairy
20 + 255 + 35
water
93.2
139.4
91.7
milk
71.5
71.3
Explanations:
Surface 1—hydrophobic liquid package using metal mould 1
Surface 2—hydrophobic liquid package using metal mould 2
Surface 3—hydrophobic liquid package using metal mould 3: 6 μm grooves cross direction, barrell lens f25.
Surface 4—hydrophobic liquid package using metal mould 4: 6 μm grooves cross direction, barrel lens f12,7.
[0068] Further it could also be detected a positive touch effect as follows. Same samples were creaking or squealing when scratching the surface with a human nail. Just holding the samples gave a touch effect that was nice and pleasant.
Example 2
[0069] Three different kinds of super hydrophobic surfaces were formed and top layer of surface was PE. All of surfaces had higher contact angles than 170° which means that drop of water will not stay on surface. It simply runs or floats away. These surfaces were formed with squares, lines and pins (as also reflected by FIGS. 6-8 . With squares and pins you could not predict the direction of drop movement. With lines the drop was following the line.
[0070] The surfaces were made of PE, in particular an LDPE for liquid packaging hoard. The PE was Borealis CA8200. PE coating of PE-coated board was too thin to get superhydrophobic surface. The testing temperature was 125° C. (to get melted PE). Tests were then done with PE-foil—9 layers of foil were put on each other and this stack was pressed with mould (form). A few PE-layers (bottom side) was replaced with PE-coated liquid packaging board and mould was on top. This stack was also pressed with mould. Mould and PE was heated and pressed together to copy the form to PE surface.
[0071] The surface metal mould was formed with laser as a replica (pattern). Thre different patterns were made and all three surfaces were superhydrophobic. Their contact angle with water drop was over 170°. It was difficult to add a drop on surface, it did not fix to the surface. If managing to spill a drop on the surface it rolled away.
[0072] Further the surface with lines had a special character. The drops rolled away at line direction. FIG. 6 reflects the pattern comprising areas with higher squares. FIG. 7 reflects the pattern comprising areas with pins. FIG. 8 reflects the pattern comprising areas with linear bulges. Said figures depict, as mentioned, three different superhydrophobic PE surfaces.
[0073] Various embodiments of the present invention have been described above but a person skilled in the art realizes further minor alterations, which would fall into the scope of the present invention. The breadth and scope of the present invention should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims and their equivalents. For example, any of the above-noted methods may be combined with other known methods. Other aspects, advantages and modifications within the scope of the invention will be apparent to those skilled in the art to which the invention pertains. | The present invention relates to a method for manufacturing a polymer product with super- or highly hydrophobic characteristics, preferably in the form of a film. Also methods for the manufacturing of a laminate and a polymer coated paper or board product, respectively, both having said characteristics, are disclosed.
The present invention also relates to products obtainable by said methods and uses thereof. | 1 |
BACKGROUND
The present invention relates to electrographic sensors, and particularly contact sensors.
Contact sensors, and particularly touchscreens, are becoming a popular input device for computers. Touchscreens allow people who have never used a computer before to easily interact with the computer. They are finding use in cars, airports, factories, shopping malls, hospitals, training centers, banks, grocery stores, libraries, and pharmacies. Common applications are automatic bank tellers, point of sale systems, and information systems found in airports for providing directions to various locations or information regarding local hotels.
One common type of touchscreen is an electrographic touchscreen or sensor of the type described in U.S. Pat. No. 4,220,815, which is incorporated herein by this reference. Such a screen typically comprises a first sheet of flexible material capable of being energized to establish an electrical potential. The sensor also has a second sheet capable of being energized to establish an electrical potential in juxtaposition with the first sheet. By pressing on the first sheet with a stylus or finger, selected portions of the two sheets come together, thereby generating an electrical signal corresponding to the locus of the portion of the flexible sheet pressed. In order to keep the two sheets separated when they are not pressed, a plurality of discrete insulating buttons or islands are provided. The islands are sized and located so pressure on the first sheet results in the two sheets contacting.
A problem of contact sensors is that the two sheets can occasionally remain in contact when the pressure is removed, i.e., the two sheets stick together. This sticking renders the device on which the sensor is being used inoperative. Such sticking can result from environmental conditions, such as high temperature and/or humidity, manufacturing defects, and the cohesive forces of the material selected.
Sticking is a serious and costly problem. Often the entire sensor needs to be replaced when sticking occurs. Moreover, the entire machine using the sensor is down and inoperative until the problem has been solved. Further, much user ill can occur when a computer system does not operate because of a defective touchscreen.
Much scientific effort has been directed to this problem. Among the solutions considered have been changing the size and/or material of the insulating islands, roughening the surface of the various sheets, changing the materials of the sheets, and providing special coatings on the sheets. None of these solutions has been totally satisfactory, either not working, or being expensive or difficult to implement.
Accordingly, there is a need for a touchscreen that has all the attributes of commercially available touchscreens, namely ease of use, without the sticking problem that plagues many of the touchscreens currently on the market.
SUMMARY
The present invention is directed to a touchscreen, or electrical sensor, that satisfies this need. The sensor comprises a transparent substrate sheet and a transparent cover sheet. The transparent substrate has a top face, a bottom face, and a first transparent conductive layer on the top face. The transparent cover sheet is above the first conductive layer with a gap between the cover sheet and the substrate. The cover sheet has a top surface, a bottom surface, and a second transparent conductive layer on the bottom surface. The cover sheet is sufficiently flexible that selected portions of the second conductive layer can be pressed into contact with corresponding portions of the first conductive layer of the substrate for generation of electrical signals corresponding to the portions of the cover sheet pressed.
In one version of the invention, one of the conductive layers can be more conductive than the other, with the less conductive layer being considered to be a "resistive" layer. In this version of the invention, electrical means can be provided to generate orthogonal electrical fields in one of the layers, typically the resistive layer.
In a second version of the invention, the two conductive layers can have substantially the same conductivity. In this version of the invention, means are attached to each of the layers to produce an electrical field in each layer, the two electrical fields being orthogonal to each other.
A plurality of insulation islands are distributed in the gap between the cover sheet and the substrate to maintain the gap in the absence of pressure on the cover sheet. The present invention is based on the discovery that by proper spacing of the islands, the sticking problem is significantly reduced, without an undue increase in the force required to press the two sheets together.
In particular, at least a portion of the insulation islands are distributed in an array having a repeating pattern so that the ratio of (i) the distance between each insulation island of said portion and its closest neighbor to (ii) the diameter of the repeating pattern is less than 0.65, and preferably less than 0.6. The term "diameter of the pattern" refers to the diameter of the largest circle that can be drawn in the pattern where the circle contains no insulation islands in its interior.
For example, the islands can be placed in an array with a repeating rectangular pattern, the rectangles having a length (l) and a width (w). The closest neighbor island is a distance (w) away. The diameter of the pattern is equal to the diagonal of the rectangle, a distance "d" apart. Thus, in such a configuration the ratio between the width (w) and the diameter (d) of the pattern, i.e., the diagonal of the rectangle, is less than 0.65, and preferably less than 0.6. In a rectangular configuration, preferably the ratio of the width (w) to the length (l) is less than 0.85, and more preferably less than 0.75.
The islands cannot be in a square configuration. The islands can be in configurations other than rectangular, such as any parallelogram (which includes a rectangle), or hexagonal or honeycomb.
Thus the sticking problem can be significantly reduced without increasing the cost of the touchscreen, and without unduly increasing the amount of force required to activate the touchscreen.
DRAWINGS
These and other features, aspects, and advantages of the present invention will become better understood from the following description, appended claims, and accompanying drawings where:
FIG. 1 is a partial sectional view of an improved sensor according to the present invention;
FIGS. 2-5 show various patterns for the insulator islands according to the present invention; and
FIG. 6 is a plot of the pressure to activate a touchscreen having a rectangular dot pattern (the pressure being normalized for a corresponding square dot pattern), versus the aspect ratio of the rectangle.
DESCRIPTION
The present invention is described with reference to a sensor or touchscreen 8 illustrated in FIG. 1, which dimensions are exaggerated to better show the components. The basic components of the device of FIG. 1 are similar to those described in U.S. Pat. Nos. 4,220,815; 4,659,873, and 4,661,655, all of which are incorporated herein by this reference. However, as described in detail below, this invention is applicable to touchscreens having a structure different than that of FIG. 1, and thus the present invention is not limited to sensors having the configuration of sensor 8.
With reference to FIG. 1, the electrographic contact sensor 8 comprises a base element or substrate 10 having a top surface 12, a bottom surface 14, and a resistive layer 16 on the top surface. The substrate can be planar, or can be contoured to match the face of a curved object such as a conventional video display screen or cathode ray tube 18 associated with data processing or the like. The substrate 10 can have any perimeter configuration, e.g., rectangular, to match the configuration of a video display. The substrate 10 can typically be rigid plastic, glass, various types of printed circuit board material, or a metal having a previously applied insulating layer. Furthermore, various plastic materials can be utilized in the form of a flexible sheet and supported upon a suitable hard surface material.
For a touchscreen, the substrate 10 is substantially transparent, and the resistive coating 16 on the substrate is likewise substantially transparent. As described in U.S. Pat. No. 4,071,689, a substantially transparent resistive layer 16 is typically a semiconducting metal oxide such as an indium-tin oxide, or less preferably tin oxide or tin antimony oxide. Coated substrates of indium-tin oxide are available, for example, from Liberty Mirror, Brackenridge, Pa. This resistive layer 16 has a highly uniform resistivity which can be a selected value in the range of 10 to 10,000 ohms per square.
Spaced a small distance from the resistive layer 16 is a transparent cover sheet 24 having a top surface 26 and a bottom surface 28. The bottom surface 28 has a conductive layer 30 thereon. There is a gap 32 between the conductive layer 30 and the resistive layer 16.
If the resultant device is to be transparent such as for a touchscreen, conductive layer 30 and the cover sheet 24 need to be transparent. Transparency is not required for a device that is an opaque sensor. The flexible film or cover sheet 24 can either be a rigid-like plastic such as polyester, or polycarbonate, or it can be elastomeric. The cover sheet 24 can be a thermal formable polyester plastic or polyvinylchloride, having a thickness of about 0.005 inch (0.125 mm).
The substantially transparent conductive layer or coating 30 can be a deposit of gold or gold-nickel having a resistivity typically of about 10 to 40 ohms per square. Alternatively, a conductive indium-tin oxide layer can be applied by conventional vacuum deposition techniques by, for example, Evaporated Metal Films, of Ithaca, N.Y. The cover sheet 24 can also be a fabric layer as described in U.S. Pat. No. 4,659,873.
Although the present invention is principally directed to transparent touchscreens, the invention is applicable to opaque products and translucent products. If the product is to be an opaque sensor, the resistive layer 16 can be applied by screening a resistive ink, by applying a resistive paint upon the substrate 10 by spraying or other coating technique, or the layer can be a volume conducting sheet such as rubber or plastic.
In opaque units, the resistive coating typically has a sheet resistivity from about 10 to about 10,000 ohms per square and is applied within a variation of uniformity of about 2% and 25%, dependinq upon the positional accuracy requirements of the device 8.
If transparency is not of concern, the conductive and resistive layers can be formed of silver, copper, or nickel.
The cover sheet 24 is sufficiently flexible that selected portions of the conductive layer 30 can be depressed into contact with corresponding portions of the resistive layer 16, i.e., close the gap 32, for generation of signals corresponding to the portions of the cover sheet pressed.
The terms "conductive layer" and "resistive layer" are used only with regard to the relative conductivity of layers 16 and 30. In view of the relatively low resistivities of both layers, both can be considered to be "conductive" layers, and are referred to as such in the claims. Moreover, is not necessary that the resistive layer be on the substrate and the conductive layer be on the cover. It is within the scope of the present invention for the resistive layer to be on the cover, and the conductive layer to be on the substrate.
The resistive layer 16 and the conductive layer 30 are spaced apart by a plurality of small insulator islands 40. The insulators 40 are sized and spaced to minimize the separation distances between the resistive layer 16 and conductive layer 30, to avoid inadvertent contact therebetween, and yet permit contact therebetween by small applied pressure of a fingertip or small object. Typically the islands have a height of about 0.0005 to about 0.015 inch. The islands are typically from about 0.002 to about 0.02 inch (0.05-0.5 mm) across. The spacing of the islands is critical to the present invention, as described below. All spaces between islands are measured from center to center.
These insulators islands 40 can be composed of any suitable insulating material. Once such material is ultraviolet curing ink, which can be positioned using conventional silkscreen or photographic techniques. A typical ink for this purpose is "Solex" distributed by Advance Exello, Chicago, Ill. The islands 40 can be attached to the conductive layer 30, as shown, or to the resistive layer 16.
Although not shown, electrical means are provided to apply orthogonal electric potentials to the resistive layer 16. Alternatively, the orthogonal electrical potentials can be applied to the conductive layer 30. Many such means are known in the art such as those of Talmage, et al. as described in U.S. Pat. No. 4,071,689, and of S. H. Cameron, et al., as described in U.S. Pat. No. 3,449,516. Both of these patents are incorporated herein by this reference. In general, these electrical means involve space-apart small electrodes attached to the resistive layer 16 along the edges thereof and circuits connected to each electrode so that each electrode along an edge has substantially the same potential, and the potential is switched in an orthogonal manner. The positioning of the small electrodes is such that electric field lines generated in the resistive layer, as a result of the applied potentials, project on to a planar surface so as to define a rectilinear coordinate system. The leads from the electrode (not shown) in the present device leave the sensor through a cable (not shown).
In an alternate version of the invention, the two layers 16 and 30 can have substantially the same conductivity. In this version of the invention, electrical means are provided to apply an electrical potential to each layer, the two electrical potentials being orthogonal to each other. A product having this structure is described in U.S. patent application Ser. No. 07/603,420, filed Oct. 26, 1990, for Ultralinear Touchscreen, by Elographics, Inc. In this configuration, the two conductive layers are formed of indium-tin oxide with a resistivity typically of 150 ohms per square.
It has been discovered that two important parameters relating to the effectiveness of operation of the sensor 8 relate to the spacing between the insulator islands 40. It has been discovered that the closer the islands are together, in particular the closer each island is to its nearest neighbor island, the less likely it is for the resistive (or conductive) layer 16 and the conductive layer 30 to remain stuck together when the gap is closed, i.e., the "sticky" problem. Contrarily, the farther apart each island 40 is from its nearest neighbor, the less force required to close the gap 32 between the resistive layer 16 and the conductive layer 30. Another factor that can affect the performance of the sensor 8 is the responsiveness of the sensor to "drag", i.e., does the device 8 correctly track a finger or other activating device as it is dragged across the outer surface 26 of the cover sheet 24? In general, the less force required to activate the sensor 8, the better the performance of the device 8 with regard to drag.
It has been discovered that the conflicting requirements of non-sticking and low force to activate, as well as good drag performance, can be accommodated by having a non-square configuration of the insulator islands. In particular, at least a portion of the insulator islands, and preferably all of the insulator islands, are distributed in an array having a regular repeating pattern, so that the ratio of (i) the distance between each insulation island and its closest neighbor to (ii) the diameter of the pattern is less than 0.65, and preferably less than 0.6. Preferably the insulation islands are uniformly distributed in the regularly repeating pattern across the entire sensor.
Examples of various suitable configurations for arrays of the insulator islands are shown in FIGS. 2-5. For example, FIG. 2 shows an array having a parallelogram pattern where each parallelogram has one side of length "o" and another side of length "l". With regard to island 48 (which is circled) in FIG. 2, the distance between that island and its closest neighbor is distance "s"; the distance is the diameter of the pattern, as shown by circle 49. According to the present invention, the ratio of s:d is less than 0.65, and preferably less than 0.6. As shown in FIG. 2, the circle 49 contains no islands in its interior, but is does have islands on its perimeter.
FIG. 3 shows the insulator islands in a rectangular array, each rectangle having a length "l" and a height "h". The array in FIG. 3 is a special case of the array in FIG. 2, where the corner angles of the parallelogram of FIG. 2 are all 90°. In the array of FIG. 3, the distance between the circled island 50 and its closest neighbor is "h", while the distance between island 50 and its farthest away neighbor is "d", this distance being the diagonal of the rectangle, which is the diameter of the pattern, as shown by circle 51. The ratio of h:d is less than 0.65, and preferably less than 0.6. Preferably the ratio of h:l is less than 0.85, and more preferably less than 0.75. It is believed a well-performing rectangular array has a length l of 0.180 inch and a height h of 0.130 inch.
FIG. 4 shows an array having a hexagonal or honeycomb pattern. In this configuration, the distance between the circled island 62 and its closest neighbor is "s", and the diameter of the pattern is d. According to the present invention the ratio of s:d is less than 0.65, and preferably less than 0.6.
It is believed that a honeycomb pattern with a good balance between sticking and pressure to activate can be achieved by having all of the side walls of the honeycomb be equal in length, with s equal to about 0.0885 inch.
FIG. 5 shows an array of islands in a generally rectangular configuration, with an extra insulation island in each side of the rectangle. The closest neighbor to island 66 is a distance "s" away, and the diameter of the pattern is "d". Thus, the critical ratio is s:d. For insulator island 68, the distance to the closest neighbor is "s'". The critical ratio for island 68 thus is s':d, and this ratio needs to be less than 0.65. Thus, for some patterns, the critical ratio is not the same for all islands.
In use, the device 8 can be activated with any device providing a force to close the circuit, such as a pen or such as a finger or a resistive probe.
The dimensions given with respect to distance between insulator islands is based on a center to center measurement. When the measurements are with regard to insulation islands that are placed on curved surfaces, the measurement is with regard to the dimension along the surface. Since the preferred method of forming insulation islands is with a silkscreen or similar process, when a silkscreen template is formed, it is formed as a planar element, and the measurements are actually in a plane. However, since the degree of curvature typical with electrographic sensors is generally relatively small, the difference between measuring along a planar surface and a curved surface is relatively insignificant.
The following examples demonstrate advantages of the present invention.
EXAMPLE 1
Sensors having the configuration of the sensor 8 of FIG. 1 were constructed using various rectangular dot patterns. Each sensor had a 0.125 inch thick substrate of glass film available from Donnely Company of Holland, Mich., coated with a resistive layer of indium-tin oxide. The top sheet 24 was 0.007 inch thick polyester film. The conductive layer 30 was made of nickel-gold. The insulating islands were formed from WR Grace Sm 3400 solder-mask, and applied using a screen of various spacings identified in Table 1. Each insulating island was about 0.001 inch in height and had a diameter at its base of about 0.010 inch.
With regard to each test sensor, the force to activate the device was measured, as well as the tendency of the device to stick. The force to activate was measured with an electronic force gauge mounted horizontally on a linear ball slide. The ball slide and force gauge were mounted on a common chassis. A screw mechanism was used to advance the forge gauge towards the touchscreen until the gap between the resistive layer and conductive layer was closed.
The tendency to stick was determined by aging specimens for 15 days at 35° C. and 95% relative humidity. Using a roller, the conductive layer was rolled into contact with the resistive layer, and the tendency to stick was visually observed. This roller sticking test was conducted every five days during the 15-day aging process.
The force to activate was determined for each specimen at five separate locations, and the average of the five locations was determined. These results are presented in Table 1.
TABLE 1__________________________________________________________________________ Force to ActivateEXAMPLE PATTERN h/l.sup.(3) h/d.sup.(4) % Sticking (OZ)__________________________________________________________________________1 0.16 × 0.16 square 1 0.71 100 (16/16).sup.(1) 2.662 0.16 × 0.12 rectangle 0.75 0.6 25 (3/12) 4.343 0.16 × 0.1 rectangle 0.63 0.53 0 (0/12) 4.894 0.16 × 0.08 rectangle 0.5 0.45 0 (0/14) 4.985 0.16 × 0.16 square.sup.(2) 1 0.71 0 (0/14) 7.96 0.105 × 0.189 rectangle 0.56 0.49 0 (0/11) 2.55__________________________________________________________________________ .sup.(1) Refers to number of samples, and number that stick .sup.(2) Squares with extra island at center of square .sup.(3) h/l -- ratio of height to length .sup.(4) h/d -- ratio of height to diameter of pattern, which for all these patterns is the diagonal of the pattern.
Comparison of the results of Example 1 against those of Examples 2, 3, 4, and 6 shows that by reducing the critical ratio to less than about 0.65, substantial reduction in sticking is achieved compared to an ordinary square configuration. Comparison of the results of Examples 2, 3, 4, and 6 against those of Example 5 shows that reducing the critical ratio to less than about 0.65 results in a substantially lower force to activate. Comparison of the results of Example 1 against those of Example 6 demonstrates that the present invention reduces sticking without an increase in the force to activate.
EXAMPLE 2
This Example demonstrates how to custom design a dot pattern, based on a theory developed regarding the pressure required to activate rectangular and square configurations. The custom design is based on a curve derived from these theoretical calculations. With reference to FIG. 6, there is shown a plot of the pressure to activate a rectangle versus the aspect ratio a/b of the rectangle, where: ##EQU1## The "pressure to activate" is the maximum pressure on the cover sheet to bring the conductive layer 30 into contact with the resistive layer 16. The curve of FIG. 6 is based on theoretical calculations where it has been determined that the pressure to activate a rectangle decreases with the fourth power of the height b for a rectangle with a fixed aspect ratio (b/a). In other words, as the height b of the rectangle increases, the pressure decreases with the fourth power of b.
This theory supports the following equation: ##EQU2## where P(a,b)/P(b,b) is the same as in FIG. 6;
P act is the pressure to activate for a rectangular dot pattern b,a; and
P o is a sured pressure to activate for a square dot pattern with spaces.
According to this example, it is known that an aspect ratio (b/a) of 0.72 is desired to minimize stickiness. It is also known that a square dot pattern of 0.160 inch per side has a satisfactorily low pressure to activate. From the above equation and FIG. 6, it is possible to specify a rectangular pattern that has about the same pressure to activate as the square of 0.16 inch per side, the rectangle having an aspect ratio of 0.72.
In particular, in equation (1) above, it is known that the desired pressure to activate (P act ) is equal to P o , the pressure to activate for the square dot pattern having desired aspect ratio)=1.39. From FIG. 6, this gives a P(a,b)/P(b,b) equal to about 0.43. Substituting into Equation 1 above yields:
0.43=b.sup.4 /(0.160).sup.4, which yields that b=0.13.
Since the aspect ratio is 0.72, a=0.13/0.72 which =0.18.
Therefore, the insulators should be in an array having a rectangular pattern of 0.13×0.18.
EXAMPLE 3
This example demonstrates how the "stickiness" of rectangular pattern can be determined relative to the stickiness of a different rectangular pattern. It is based upon the determination that the stickiness of a rectangular pattern is inversely proportional to the fourth power of the minimum distance between the insulation islands of the pattern, which is the width of a rectangle. Accordingly, from the results of Example 2, it can be determined that by changing from a square dot pattern of 0.16×0.16 to a rectangular dot pattern of 0.13 to 0.18, the relative amount of stickiness is decreased by a factor of (0.13/0.16) 4 =0.44, which means the stickiness is decreased by over 50 percent.
The present invention has significant advantages. It solves the problem of sticking, without increasing the force to activate so much that the device is no longer useful. Moreover, it accomplishes this in an economical way that does not require any change of materials or any change of fabrication process.
Although the present invention has been described in considerable detail with reference to certain preferred versions thereof, other versions are possible. For example, the present invention is not limited to electrographic sensors, but can be used for any sensor comprising spaced apart sheets that are intermittently pressed together. Therefore, the spirit and scope of the appended claims should not be limited to the description of the preferred versions contained herein. | A contact sensor comprises a first sheet of flexible material and second sheet. The first sheet is capable of being energized to establish an electrical potential thereon. The second sheet can be energized to establish an electrical potential in juxtaposition with the first sheet. The two sheets are formed of materials that tend to stick together. To keep the sheets apart, a plurality of substantially uniform discrete insulating islands are used. By the use of a non-square insulating island spacing pattern with the island spacing satisfying rigorous criteria, the two sheets can be prevented from sticking together without unduly increasing the amount of force required to activate the device. The sensor is particularly useful as a transparent touchscreen. | 8 |
FIELD OF THE INVENTION
The present invention relates to that type of door check which utilizes a slotted hasp hinged on a vertical axis. A slide member secured to the door slides in the slot, permitting the door to be opened to a limited extent.
REFERENCE TO DISCLOSURE DOCUMENT
Much of the subject matter of the present invention is contained in Disclosure Document No. 092771 filed by the present inventors in the United States Patent and Trademark Office July 31, 1980. To the extent of common disclosure, the priority of that document is claimed.
BACKGROUND OF THE INVENTION
Door checks which provide for limited opening of a door, by use of a hasp hinged on a vertical axis and slotted to receive a headed slide bolt which projects from a housing mounted on the door projecting across the door edge, are well known. It is conventional that the housing which bears the slide bolt may have a flat inward vertical surface against which the hasp may be folded, the housing wall having a thumb screw over which the slot of the hasp may pass, to be turned to retain the hasp against the inner surface of the housing and thus serve as an additional locking device.
That construction permits only one extent of door opening. Hasp type devices have been patented, however, which permit at least two extents of door opening, for example, a narrow opening through which the persons inside and outside the door may converse or through which a letter may be passed, and a larger opening through which a small package may be passed; but such devices involved increased complexity. For example U.S. Pat. No. 1,785,772 to Hallman makes provision for hinging the plate which mounts the hasp to the door jamb, so that the hasp axis may be rotated out of vertical; and a somewhat similar provision is made in U.S. Pat. No. 179,308 to Hill. U.S. Pat. No. 197,577 to Whipple adds an axially sliding bolt to achieve retention in more than one position along the slotted hasp. In each of these devices, the slot in the hasp has but a single width, interrupted by notches which make possible the multiplicity of positions.
SUMMARY OF THE INVENTION
The objects of the present invention are to utilize a hasp whose hinge axis is fixed in a vertical position, to provide at least two extents of opening of the door check device. Still another object is to provide for quick change in the degree of opening; and as an additional object; to provide for easy installation without cutting into the trim which ordinarily projects inward a substantial fraction of an inch beyond the inner surface of the door. Still further objects will be apparent from the disclosure which follows.
We attain these purposes by the use of a hasp, conventionally mounted with its vertical hinge axis in fixed position a substantial fraction of an inch inward of the door inner surface, by providing the hasp with a slot which continues, from a conventional large yoke-like opening at the hinge, outward first in the provision of a slot of greater width, and continuing outward therefrom in the provision of a slot of narrower width. To fit within these two different widths, we utilize an axially fixed slide member having both a greater depth slide portion, to fit slidably within the slot portion of greater width, and a lesser depth portion, to fit slidably within the outward-continuing narrower width portion of the slot.
In one embodiment of our invention, the slide member is formed integrally with the vertical sheet metal wall of the housing affixed to the door. Since the inward extent of this housing approximates the thickness of the door trim, installation of this embodiment ordinarily requires no cutting of the door trim. In another embodiment, the two depths of slider are provided by use of an oblong member, rotatable through an angle of 90° to present, at the choice of the person inside the door, either the greater or lesser dimension of the oblong for sliding in such dual-width slot of the hasp. Thus when the greater dimension is presented vertically, the door can be opened only to the minimum extent; whereas by rotating 90°, the smaller dimension of the oblong is presented vertically, so that the slider may slide to the extreme end of the slot.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view showing a preferred embodiment of the present invention installed on the inner surface of a door, shown fragmentarily, in position prior to opening to engage the check.
FIG. 2 is a view from the left end of FIG. 1 showing the slide with its deeper part engaged at the juncture of the broader and narrower parts of the hasp slot and with the door shown in minimum open position.
FIG. 3 is an elevational view of the integral housing and slide of FIG. 1.
FIG. 4 is an elevational view of alternate embodiment of the invention using a 90° rotatable oblong slide.
FIG. 5 is a cross-sectional view taken along line 5--5 of FIG. 4. The phantom lines show the position of the parts when the shallower slide is selected.
FIG. 6 is a right end view of FIG. 4. The phantom lines show the slide lever rotated up 90° to select such shallower slide.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The embodiment of invention shown in FIGS. 1-3 is to be installed preferably without disturbing the door trim/casing on its inner side. Such trim/casing normally extends about a half inch inward of the surface of a door. FIG. 1 shows fragmentarily such a door jamb 10, trim 11 and door 12.
This embodiment of the invention utilizes a hasp assembly generally designated 15 whose mounting plate 16 is mortised into the door jamb 10 by conventional one-way screws (not shown) having slots whose reverse face portions are so beveled as to make impossible removal with an ordinary screw driver. The mounting plate has a yoke-like clevis hinge portion 17 defining a fixed vertical axis.
On the clevis hinge portion 15 is mounted a swinging hasp 20 having hinge lugs 21 complementary to the clevis hinge 17. A hasp slot generally designated 25 has a somewhat yoke-like broad entrant portion 26 leading curvingly into what is herein referred to as a broader slot portion 27, which may extend roughly one-third of the length of the hasp 20. The broader slot portion 27 leads in turn to a narrower slot portion 28 terminating in a slot end 29; the narrower slot portion 28 is preferably two or more times as long as the broader slot portion 27 and meets it at a shoulder-like juncture 30.
Inasmuch as the yoke-like entrant portion 26, broader slot portion 27 and narrower slot portion 28 are all formed symmetrically about a line perpendicular to the vertical axis of the clevis hinge 17 (which is mounted to be rigidly vertical), opening the door 12 on a vertical axis will draw the slide member, to be described, smoothly along such a perpendicular line.
Spacedly forward of the shoulder-like juncture 30 but preferably fairly close to it is a vertically enlarged passage notch 31, whose function will subsequently be described.
In contrast to the axially sliding bolt arrangement of U.S. Pat. No. 197,577, we utilize in this embodiment an integral housing and slide member generally designated 35, best seen in FIGS. 1 and 3. It is formed preferably as a sheet metal stamping to have a box-like configuration, including upper and lower flanges 36 to be screwed to the inner surface of the door as shown, with upper and lower box walls 37 projecting inward therefrom to an inward vertical wall 38. An outer end wall 39, bent forward from the vertical wall 37, affords a finished appearance to the stamping.
Mounted at about the middle of the inward vertical wall 38 is a thumb latch 40 having a short cylindrical shank 41 which is headed inwardly of the vertical wall 38, so that the latch 40 may be turned from horizontal position, shown in FIG. 1, to the vertical position shown in FIG. 3. In horizontal position, the thumb latch 40 will pass through the slot 25; when the door 12 is closed the swinging hasp 20 may be folded over the latch 40 and the hasp then locked in place by turning the latch to vertical position. This affords additional security, should the door be left otherwise unlocked or its lock tampered with.
Projecting horizontally from the inward vertical wall 38 is an integral key-like slide member generally designated 45. Preferably it has a stamped central reinforcing rib 46 which extends horizontally through a substantial portion of the inward vertical wall 38, bending it slightly out of vertical as shown; this affords extra bending strength perpendicular to the original vertical plane of the sheet metal. Extending symmetrically on the upper and lower sides of the slide member 45, to the left of the vertical wall 38 as seen in FIG. 3, is a deeper slide portion 47, of such width as to fit slidably within the broader slot portion 27 of the hasp 20; and a shallower slide portion 48, whose depth is such to fit slidably within the narrower hasp slot portion 28. Between the two slide portions 47, 48 is a separator or guard portion 49, too deep to fit within the broader slot portion 27, but of slightly less depth than the total depth of the passage notch 31 in the hasp 20. Finally, at the outermost end of the integral slide member 45 is a vertically enlarged tip portion 51 whose extent is greater than such depth of the passage notch 31 but less than the height of the yoke in the mounting plate clevis hinge 17 or the height of the yoke-like entrant portion 26 of the hasp slot 25.
The components described are mounted in the manner shown in FIG. 1. The integral housing and slide member 45 is mounted adjacent to the inward-opening edge of the door 12 with the slide member 45 projecting precisely horizontally parallel to such door inner surface as there shown, to present the vertically enlarged tip portion 51 just beyond the vertical axis of the clevis hinge 17 of the mounting plate 16. Because of the inward extent of the housing vertical wall 37 from the inner surface of the door 12, the key-like slide portion 47 will normally clear the door trim 11 without any cutting away, which greatly facilitates installation as compared with conventional swinging hasp door checks. The vertical axis of the clevis hinge 17 is so positioned that when the swinging hasp 20 is folded it will fit flatwise against the housing inward wall 38 for securement; it fits about the cylindrical shank 41 of the thumb latch 40 to permit turning to the vertical locking position shown in FIG. 3. If the user wishes to open the door completely, he merely turns the thumb latch 41 horizontally and swings the hasp 20 to the left of the FIG. 1 position, so that the slide member tip portion 51 may, on opening, move without interference through the yoke-like entrant portion 26 of the hasp 20.
If the user wishes to open the door only slightly and there check its movement, as shown in FIG. 2, he swings the hasp 20 far enough to the right to utilize its broader slot portion 27 over the deeper slide portion 47, and opens the door inward as shown in FIG. 2. The upper and lower edges of the deeper slide portion 47 will thus come to a stop against the shoulder-like juncture 30 at the entrance to the narrower slot portion 28. The user will thus be secure; the extent of the door opening is too slight to permit the insertion of a tool or any other manipulation which might endanger those inside. If it were otherwise possible to deflect the hasp 20 angularly, the separator or guard portion 49 makes such angular movement impossible when the slide member 45 is engaged against the shoulder 30 as shown in FIG. 2.
Should the user desire to permit the door to be opened somewhat farther, so that a parcel may be handed through the opening, for example, he presses the door slightly toward the jamb, bringing the slide member 45 into alignment with the passage notch 31. Then, on passing the guard portion 49 through the passage notch 31, the hasp 20 may be moved angularly until stopped by the vertically enlarged slide tip portion 51. This permits the user to open the door farther inward, with the shallower slide portion 48 sliding in the hasp narrower slot portion 28 until it comes to rest against the hasp slot end 29.
The alternate embodiment, illustrated in FIGS. 4, 5 and 6 likewise affords two degrees of opening, utilizing, however, different mechanism for this purpose.
A hasp assembly 15' is identical, save for lack of a passage notch, with the hasp assembly of the prior embodiment; and it is similarly installed. The slot 25' in its swinging hasp 20' has a yoke-like entrant portion 26', a broader slot portion 27' and a narrower slot portion 28', the latter meeting at a shoulder-like juncture 30', as in the previous embodiment. The extent of the broader slot portion 27' from the yoke-like entrant portion 26' to the shoulder-like juncture 30' may be the same as in the first described embodiment; and likewise the length of the narrower slot portion 28' to the slot end 29'.
A box-like housing generally designated 55 is formed as a heavy sheet metal stamping, having upper and lower flanges 56 to be screwed to the door inner surface, inward projecting upper and lower box walls 57, a vertical inward wall 58, a partial outer end wall 59 hereinafter referred to, and a complete inner end wall 62. A thumb latch 40' having a cylindrical shank 41', identical to the corresponding parts of the prior described embodiment, is similarly mounted in the middle of the inward vertical wall 58.
Horizontally aligned bores 63 are provided in the inner end wall 62 and outer end wall 59 to receive a round selector shaft 65, having at its outer end, shown to the right in FIG. 4, a 90° bent lever portion 66. Angular movement of the selector shaft 65 in the bores 63 is limited to 90° by tab-like end stops 67, blanked and bent upward and slantingly toward each other from portions of the outer end wall 59, as shown in FIGS. 4 and 6. If desired, other 90° stop means may be utilized.
At the inner end of the selector shaft 65, opposite to the bent lever end 66, is rigidly mounted a slide member generally designated 70, designed to cooperate with the swinging hasp 20'. The slide member 70, seen in elevation in FIG. 4, has a head end 71 which may be round; it is of greater vertical extent than the broader slot portion 27' but sufficiently small to fit within the yoke-like entrant portion 26' of the hasp 20'. Between the head end 71 and the inner end wall 62 of the housing 55, the slide member 70 has an oblong slide portion 72, best seen in cross-section in FIG. 5. Specifically, its surfaces of smaller area 73, shown above and below in solid lines of FIG. 5, are so spaced apart as to effect a sliding fit within the broader slot portion 27' of the swinging hasp 20'; while its larger faces 74 are spaced more closely, at a spacing designed to fit slidably within the narrower slot portion 28'.
Rotating the selector shaft 65 by moving its lever end 66 from the lower position shown in solid lines in FIGS. 4, 5 and 6 to the upper phantom line positions of FIGS. 5 and 6 (in both cases against the bent limit stops 67), turns the oblong slide portion 72 from the solid line position shown in cross-section in FIG. 5 to the phantom line position there shown. Utilizing the phantom line position of the oblong slide portion 72, the door can open to the fullest extent permitted by the narrower slot portion 28' of the hasp 20'; whereas if the solid line position of the lever 66 is selected, after the hasp 20' is in place the oblong slide portion 72 can slide only as far as the shoulder-like juncture 30', limiting the door opening to the same extent as shown in FIG. 2 for the first embodiment.
Utilizing either of these embodiments, a selection of two extents of opening is afforded to the user without danger of tampering from the outside by someone who has induced the user to open the door slightly. For lower manufacturing cost and installation without substantially cutting the door trim, the first embodiment may be preferred.
From this disclosure, modification will be apparent. For example, door checks providing three extents of opening may be constructed in the manner of the first embodiment herein; and other variations in detailed features of construction and use will be suggested to those familiar with the door-check art.
In the claims, the terms "broader" and "narrower" as referring to portions of the slot in the hasp, are to be taken as measured vertically, as are the terms "deeper" and "shallower" in referring to portions of the slide. | A door check of the swingable slotted hasp type provides two extents of opening, utilizing a broader width of slot which continues outward in a slot of narrower width. Two different depths of slide member are provided. In one embodiment these are spaced axially along a horizontal projection from a housing on the door. In another, the slide is oblong, and is rotatable through 90° to present the two different depths. | 8 |
PRIORITY CLAIM
This is a U.S. national stage of application No. PCT/EP2204/014723, filed on Dec. 27, 2004. Priority is claimed on that application and on the following application:
Country: Europe, Application No.: 04405008.6, Filed: Jan. 6, 2004.
BACKGROUND OF THE INVENTION
Subject of the invention is an elevator installation.
Elevator installations of the kind according to the invention usually comprise an elevator cage and a counterweight, which are movable in an elevator shaft or along free-standing guide devices. For producing the movement the elevator installation comprises at least one drive with at least one respective drive pulley, which, by way of support means and/or drive means, support the elevator cage and the counterweight and transmit the required drive forces to these.
In the following, for the sake of simplicity the support means and/or drive means are termed only support means.
An elevator system without an engine room is known from WO 03/043926, in which wedge ribbed belts are used as support means for the elevator cage. These belts comprise a belt body of flat belt form which is produced from a resilient material (rubber, elastomer) and which has, on its running surface facing the drive pulley, several ribs extending in the belt longitudinal direction. These ribs co-operate with grooves, which are formed to be complementary thereto, in the periphery of driving or deflecting pulleys (termed belt pulleys in the following) in order on the one hand to guide the wedge ribbed belt on the drive pulleys and on the other hand to increase the traction capability between the drive pulley and the support means. The ribs and grooves have triangular or trapezium-shaped, i.e. wedge-shaped, cross-sections. Tensile carriers consisting of metallic or non-metallic strands are embedded in the belt body of the wedge ribbed belt and oriented in the belt longitudinal direction, which tensile carriers impart the requisite tensile strength and longitudinal stiffness to the support means.
The wedge-ribbed belts known from WO 03/043926 have certain disadvantages, i.e. they are not optimally adapted to the requirements of a support means for elevator cages. Such support means have to have a high load-bearing capability and a low longitudinal elasticity for smallest possible dimensions and smallest possible own weight and in that case be able to be guided over driving and deflecting pulleys with smallest possible diameters.
The wedge ribbed belts used as support means in accordance with WO 03/043926 exhibit, by comparison with the cross-sections of the tensile carriers, relatively large cross-sections of the belt bodies, i.e. the thickness of the belt bodies is large in relation to the diameter of the tensile carriers, and the edge regions, which face the pulleys and rollers, of the belt bodies, particularly the tips of the wedge-shaped ribs, are spaced comparatively far from the tensile carriers. In the case of the cross-section, which is given by the required load-bearing strength, of the tensile carriers this means that the disclosed wedge ribbed belts on the one hand have more than the absolutely necessary amount of material for the belt body and thus are too heavy and too expensive. On the other hand, the material of the belt body, which is relatively high in bending direction, is needlessly strongly loaded by alternating bending stresses when the support means runs around a drive pulley or a deflecting roller of small diameter, which can lead to formation of cracks and premature failure of the support means. In particular, the regions of the belt body spaced far from the tensile carriers, i.e. the tips of the wedge-shaped ribs, are exposed to strong alternating bending stresses.
SUMMARY OF THE INVENTION
The present invention is based on the task of creating an elevator installation of the afore-described kind in which the stated disadvantages are not present, i.e. that the an elevator installation comprises a support means of flat belt form with ribs, which in the case of use with minimum belt pulley diameters and for a predetermined load-bearing capability has minimum dimensions and minimum weight, wherein the tensile carriers and the belt body are exposed to the smallest possible loads so that an optimum service life is guaranteed.
Pursuant to this task, one aspect of the present invention resides in an elevator installation having a support means of flat belt form which has at least on a running surface facing the drive pulley several ribs extending parallelly in the belt longitudinal direction, wherein at least two tensile carriers oriented in the belt longitudinal direction are present per rib and the sum of the cross- sectional areas of all tensile carriers amounts to at least 25%, preferably 30% to 40%, of the total cross-sectional area of the support means. For ascertaining the total cross-sectional area of the tensile carriers, the cross-section defined by the outer diameter thereof is to be taken into account.
Through the distribution of the load to two tensile carriers (with the requisite cross-section) per rib it is achieved that the tensile means when the support means runs over belt pulleys with small diameters are exposed to smaller alternating bending stresses than if a single tensile carrier with correspondingly larger diameter were used per rib. With the indicated relationship between the sum of the cross-sectional areas of all tensile carriers and the cross-sectional area of the support means there is defined a support means which has optimally small dimensions and material quantities. The optimum small dimensions also have the consequence of correspondingly small alternating bending stresses in the material of the belt body. Materials (rubber, elastomer) can therefore be selected for production of the belt body which have a lower permissible bending stress, but tolerate higher area pressures between tensile carriers and belt body.
According to a preferred refinement of the invention there are used in the support means tensile carriers with a substantially round cross-section, the outer diameter of which amounts to at least 30%, preferably 35% to 40%, of the rib spacing. As rib spacing there is to be understood the spacing between adjacent ribs of a support means, which is usually the same between all ribs of a specific support means. In the case of a support means constructed in accordance with this rule it is ensured that the forces which are to be transmitted by the tensile carriers via the belt body to a drive pulley or a deflecting roller are optimally distributed in the belt body and the area pressures arising between tensile carriers and belt body are optimally small. The risk is thereby minimised that a loaded tensile carrier cuts through the belt body.
Advantageously the ribs have a wedge-shaped cross-section with a flank angle of 60° to 120°, wherein the range of 80° to 100° is to be preferred. The angle present between the two side surfaces (flank) of a wedge-shaped rib is termed flank angle. With flank angles of 60° to 120° it is ensured on the one hand that when the support means runs over belt pulleys no jamming between the ribs and the grooves, which are formed to be complementary thereto, of the belt pulleys arises. Running noises as also excitation of vibrations of the wedge-ribbed belt are thereby reduced. On the other hand, with such flank angles a sufficient guidance of the support means on the belt pulleys can be achieved, which prevents the lateral displacement of the support means relative to the belt pulleys.
An ideal distribution of the forces introduced from the belt body into the tensile carriers is achieved inter alia in that the spacings between the centres of tensile carriers associated with a specific rib are at most 20% smaller than the spacings between the centres of adjacent tensile carriers associated with adjoining ribs.
Optimally small dimensions and low weight of the support means are achievable if the minimum spacing of the outer contour of a tensile carrier from a surface of a rib amounts to at most 20% of the total thickness of the support means. The total thickness of the belt body with the grooves is to be understood as total thickness.
According to a preferred refinement of the invention the tensile carriers associated with a rib are so arranged that a respective outer tensile carrier lies substantially in the region of the perpendicular projection of each flank of the wedge-shaped rib. A projection oriented perpendicularly to the plane of the flat side of the support means is termed perpendicular projection and by “substantially” there is to be understood that at least 90% of the cross-sectional area of the respective tensile carrier lies within the said projection.
In the case of a particularly advantageous form of embodiment a respective outer tensile carrier is arranged entirely in the region of the perpendicular projection (P) of each flank of a wedge-shaped rib.
With the two arrangements, defined in the foregoing, of the tensile carriers in the flank region it is guaranteed that when running around a belt pulley no tensile carrier has to be supported by that point of the belt body which has the deepest notching formed by the grooves lying between the ribs.
In order to obtain support means which for a given tensile loading have a smallest possible longitudinal stretching, tensile carriers of steel wire cables are used. Steel wire cables are less stretched, for the same loading, than, for example, tensile carriers with the same cross-section of conventional synthetic fibres.
A support means with particularly low permissible bending radii, which is suitable for use in combination with belt pulleys of small diameter, can be achieved in that the steel wire cables have an outer diameter of less than 2 millimetres and are twisted from several wires which in total contain more than 50 individual wires.
BRIEF DESCRIPTION OF THE DRAWINGS
Examples of embodiment of the invention are explained by reference to the accompanying drawings, in which:
FIG. 1 shows a section, which is parallel to a lift cage front, through a lift installation according to the invention;
FIG. 2 shows an isometric view of the rib side of a support means according to the invention in the form of a wedge ribbed belt;
FIG. 3 shows a section through a first wedge ribbed belt forming the support means of the lift installation;
FIG. 4 shows a section through a second wedge ribbed belt forming the support means of the lift installation; and
FIG. 5 shows a cross-section through a steel wire tensile carrier of the wedge ribbed belt.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows a section through an elevator system according to the invention installed in an elevator shaft 1 . Essentially illustrated are:
a drive unit 2 , which is fixed in the elevator shaft 1 , with a drive pulley 4 . 1 an elevator cage 3 , which is guided at cage guide rails 5 , with cage support rollers 4 . 2 mounted below the cage floor 6 a counterweight 8 , which is guided at counterweight guide rails 7 , with a counterweight support roller 4 . 3 a support means, which is constructed as a wedge ribbed belt 12 , for the elevator cage 3 and the counterweight 8 , which support means transmits the drive force from the drive pulley 4 . 1 of the drive unit 2 to the elevator cage and the counterweight. (In the case of an actual elevator installation, at least two wedge ribbed belts arranged in parallel are present)
The wedge ribbed belt 12 serving as support means is fastened at its end below the drive pulley 4 . 1 to a first support means fixing point 10 . From this it extends downwardly to the counterweight support roller 4 . 3 , loops around this and extends out from this to the drive pulley 4 . 1 , loops around this and runs downwardly along the cage wall at the counterweight side, loops around, at both sides of the elevator cage, a respective cage support roller 4 . 2 , which is mounted below the elevator cage 3 , in each instance by 90° and runs upwardly along the cage wall remote from the counterweight 8 to a second support means fixing point 11 .
The plane of the drive pulley 4 . 1 is arranged at right angles to the cage wall at the counterweight side and its vertical projection lies outside the vertical projection of the elevator cage 3 . It is therefore important that the drive pulley 4 . 1 has a small diameter, so that the spacing between the cage wall at the left side and the wall of the elevator shaft 1 opposite thereto can be kept as small as possible. Moreover, a small drive pulley diameter enables use of a drive motor without transmission and with a relatively small drive torque as drive unit 2 .
The drive pulley 4 . 1 and the counterweight support roller 4 . 3 are provided at their periphery with grooves which are formed to be complementary to the ribs of the wedge ribbed belt 12 . Where the wedge ribbed belt 12 loops around one of the belt pulleys 4 . 1 and 4 . 3 its ribs lie in corresponding grooves of the belt pulley, whereby a perfect guidance of the wedge ribbed belt on these drive pulleys is guaranteed. Moreover, the traction capability is improved by the wedging action arising between the grooves of the belt pulley 4 . 1 serving as drive pulley and the ribs of the wedge ribbed belt 12 .
In the case of support means under-looping below the elevator cage 3 no lateral guidance is given between the cage support rollers 4 . 2 and the wedge ribbed belt 12 , since the ribs of the wedge ribbed belt are disposed on its side remote from the cage support rollers 4 . 2 . In order to nevertheless ensure lateral guidance of the wedge ribbed belt there are mounted at the cage floor 6 two guide rollers 4 . 4 provided with grooves which co-operate with the ribs of the wedge ribbed belt 12 as lateral guidance.
FIG. 2 shows a section of a wedge ribbed belt 12 . 1 , which serves as support means, of an elevator installation according to the invention. The belt body 15 . 1 , the wedge-shaped ribs 20 . 1 and the tensile carriers 22 embedded in the belt body can be recognised.
FIG. 3 shows a cross-section through a wedge ribbed belt 12 . 1 according to the present invention, which comprises a belt body 15 . 1 and several tensile carriers 22 embedded therein. The belt body 15 . 1 is produced from a resilient material. Natural rubber or a number of synthetic elastomers are, for example, usable. The flat side 17 of the belt body 15 . 1 can be provided with an additional cover layer or a fabric layer which is worked in.
The traction side, which co-operates at least with the drive pulley 4 . 1 of the drive unit 2 , of the belt body 15 . 1 has several wedge-shaped ribs 20 . 1 which extend in the longitudinal direction of the wedge ribbed belt 12 . 1 . A belt pulley 4 , in the periphery of which grooves complementary to the ribs 20 . 1 of the wedge ribbed belt 12 . 1 are formed, is indicated by means of phantom lines.
Two round tensile carriers 22 are associated with each of the wedge-shaped ribs 20 . 1 of the wedge ribbed belt 12 . 1 and are so dimensioned that they can in common transmit the belt loads arising in the wedge ribbed belt per rib. These belt loads are on the one hand the transmission of pure tensile forces in the belt longitudinal direction. On the other hand, in the case of looping around of a belt pulley 4 . 1 - 4 . 4 forces are transmitted in a radial direction from the tensile carriers via the belt body to the belt pulley. The cross-sections of the tensile carriers 22 are so dimensioned that these radial forces do not cut through the belt body 15 . 1 . In the case of looping around of a belt pulley additional bending stresses arise in the tensile carriers as a consequence of the curvature of the wedge ribbed belt resting on the belt pulley. In order to keep these additional bending stresses in the tensile carriers 22 as small as possible the forces to be transmitted per rib 20 . 1 are distributed to two tensile carriers, although a single tensile carrier arranged in the centre of the rib would enable a somewhat smaller overall thickness of the wedge ribbed belt.
Through extensive tests there has been ascertained an arrangement of belt body 15 . 1 and tensile carriers 22 which, for a given belt pulley diameter D of approximately 90 millimetres, a given tensile load and a given permissible alternating bending stress of the tensile carriers and the belt body material, a smallest possible total cross-section for a smallest possible weight of the wedge ribbed belt results. As an important criterion for a wedge ribbed belt with the stated properties it has in that case resulted that the proportion of the total cross-sectional area of all tensile carriers to the cross-sectional area of the wedge ribbed belt shall amount to at least 25%, preferably 30% to 40%.
The wedge ribbed belt illustrated in FIG. 3 fulfils this criterion. For ascertaining the total cross-sectional area of all tensile carriers the cross-section, which is defined by outer diameter DA shown in FIG. 5 , of the wire cable is to be taken into consideration.
In the case of a wedge ribbed belt 12 . 1 with two tensile carriers per rib 20 . 1 the aforesaid characteristics are achieved in particularly optimal manner if the outer diameter of a tensile carrier amounts to at least 30% of the rib spacing. The uniform pitch spacing T of the ribs is termed rib spacing.
FIG. 4 shows a variant 12 . 2 of the wedge ribbed belt, in which the wedge-shaped ribs 20 . 2 are wider than in the case of the variant 12 . 1 illustrated in FIG. 3 and each have three associated tensile carriers. All other characteristics stated in connection with the variant according to FIG. 3 are similarly present in the case of this variant. Such a wedge ribbed belt has the advantage that the corresponding belt pulleys 4 . 1 , 4 . 3 , 4 . 4 are somewhat easier to produce.
The wedge ribbed belts illustrated in FIGS. 3 and 4 and serving as support means have a preferred flank angle βof approximately 90°. The angle present between the two flanks of a wedge-shaped rib of the belt body is termed flank angle. As already explained in the description of advantages tests have shown that the flank angle has a critical influence on the development of noise and the creation of vibrations and that flank angles βof 80° to 100° are optimal, and from 60° to 120° usable, for a wedge ribbed belt provided as elevator support means.
It is also recognisable in FIGS. 3 and 4 that the spacings A between centres of the tensile carriers 22 associated with a specific rib are slightly smaller than the spacings B between centres of adjacent tensile carriers of adjoining ribs. This is caused by the maintenance of a minimum requisite spacing of the tensile carriers 22 from the edges of the ribs 20 . 1 , 20 . 2 . In that the differences in the spacings are kept as small as possible, a homogeneous distribution of the forces introduced by the belt body into the tensile carriers is guaranteed. It has proved advantageous if the spacings A are not more than 20% smaller than the spacings B.
Moreover, it can be inferred from FIGS. 3 and 4 that small dimensions and low weight of the wedge ribbed belt can be achieved in that the spacings X between the outer contours of the tensile carriers and the surfaces of the ribs are formed to be as small as possible. Tests have yielded optimum characteristics for wedge ribbed belts in which these spacings X amount to at most 20% of the total thickness s of the support means or at most 17% of the pitch spacing T present between the ribs 20 . 1 , 20 . 2 . The total thickness of the belt body 15 . 1 , 15 . 2 together with the ribs 20 . 1 , 20 . 2 is to be understood as total thickness s.
Particularly small dimensions and good running characteristics have resulted for wedge ribbed belts 12 . 1 , 12 . 2 when the tensile carriers 22 associated with a rib 20 . 1 , 20 . 2 are so arranged that a respective outer tensile carrier lies substantially or entirely in the region of the perpendicular projection P of each flank of the wedge-shaped rib 20 . 1 , 20 . 2 .
FIG. 5 shows in enlarged illustrated a cross-section through a preferred form of embodiment of a tensile carrier 22 , which is predominantly suitable for a wedge ribbed belt for use in an elevator installation according to the invention. The tensile carrier 22 is a steel wire cable which is twisted from in total 75 individual wires 23 with extremely small diameters.
In order to achieve a long service life of the support means in elevator installations with belt pulleys of small diameter it is of substantial advantage if the steel wire cables used as tensile carriers 22 consist of at least 50 individual wires. | The invention relates to a lift system wherein a drive unit ( 2 ) drives, by means of a driving disk ( 4.1 ), a flat belt-type carrier means ( 12.1, 12.2 ) which carries the lift cage ( 3 ). Said flat belt-type carrier means comprises several ribs ( 20.1, 20.2 ) which extend in a parallel manner in a longitudinal direction of the carrier means on a bearing surface which is orientated towards the driving disk ( 4.1 ) and each rib comprises at least two traction carriers ( 22 ) which are orientated in a longitudinal direction of the carrier means. The whole cross-sectional surface of all the traction carriers ( 22 ) is at least 25% of the cross-section surface of the carrier means. | 3 |
TECHNICAL FIELD
[0001] The present invention relates to a biochip for use in Raman quantitative analysis of a biological sample.
BACKGROUND ART
[0002] In order to acquire information useful in diagnosis, stage classification understanding and treatment of human diseases, it is necessary to know the sequences of human protein that are estimated in excess of 30,000 and to identify the important change in expression of protein that announces imminent crisis of the disease. It is also necessary to accurately classify the subtype of the disease on the molecular level so that the function, interrelation and activity of the protein closely related with the process of the disease can be adjusted. One of the bottommost ways to understand the function of the protein is to functionally associate the change of the level of expression with the vegetative stage, cell cycle state, stage of the disease, external stimulation, expression level or any other variable and, although DNA microarray analysis leads to mRNA expression assay method on the genome scale, no direct relation is often found between the in-vivo concentration of mRNA and the coded protein. Accordingly, the difference in speed of translation of mRNA to protein and the difference in speed of in-vivo proteolysis are considered a factor that results in disturbance to the extrapolation of mRNA to the protein expression profile.
[0003] Also, such a microarray assay referred to above often plays an important role in protein functional regulation, but is unable to detect, identify or quantitatively determine the protein modification.
[0004] Accordingly, the quantitative analysis against the detection and the analysis of analyte of a low concentration contained various biological samples generally necessitates labelling with the use of a radioactive isotope or a fluorescence reagent, and such method generally requires a substantial amount of time and is, hence, inconvenient to accomplish. For example, although various qualitative analyzing methods, two dimensional electrophoretic method and liquid chromatography have been widely used for the protein profiling, they are not adequate for use in summary survey.
[0005] Yet, in view of the solid state sensor, particularly biosensor, that is increasingly used in chemical, biological or pharmaceutical studies, such sensor is in recent years drawing unprecedented attention and makes use of a conversion structure capable of converting two elements; a recognition element of high uniqueness and a molecular recognition event, into a quantifiable signal and has been developed with the aim of detecting various biological molecular complexes including oligonucleotide pairs, antibody-antigen complex, hormone-acceptor complex, enzyme-substrate complex and lectin-glycoprotein complex interaction, but it still insufficient.
[0006] In view of the foregoing, the use of Raman scattering spectroscopy or a surface plasmon resonance has been suggested with the aim of accomplishing an objective to enable a highly accurate detection or identification of individual molecules in the biological sample. The wavelength of Raman scattering spectroscopy is characteristic of a chemical composition and structure of Raman scattering molecules in the sample and the intensity of Raman scattered light depends on the molecular concentration in the sample. In the practice of Raman scattering spectroscopy, nanoparticles of gold, silver, copper and any other plasmon metal exhibit a surface intensified Raman scattered effect in response to the applied laser beams and, using it, biological molecules of interest are characterized such that nucleotide, deoxyadenosine monophosphate, protein and hemoglobin could be detected at a single molecular level. As a result, however, SERS (surface enhanced Raman spectroscopy) could not be considered suitable for use in quantitative analysis of the protein content in the complex biological sample such as blood plasma.
[0007] In view of the foregoing, the need has arisen of a method of analyzing the protein composition of a sample of the complex organism in blood serum or the like with the use of Raman scattering spectroscopy to detect or identify the individual proteins with reliability, as well as high throughput means for quantitatively and qualitatively detecting the protein of a low concentration level in a composite sample. Accordingly, a method for analyzing the protein content in a biological sample has been suggested, in the patent document 1 listed below, which method includes isolating protein and protein segments in the sample based on chemical and/or physical characteristics of the protein, maintaining in an isolated condition the isolated proteins at the discrete positions on a solid substrate or in the flow of liquid then flowing, detecting Raman spectrum formed by the isolated proteins at the discrete positions so that through the spectrum at the discrete positions, information on the structure of one or more particular proteins at discrete positions can be provided. Also, SERS phenomenon involves some problems to be resolved in terms of repeatability and reliability because of (1) the mechanism not yet comprehended impeccably, (2) difficulties in formation of the nano-material, which is accurately and structurally defined, and in control, and (3) change in enhancement efficiency brought about by wavelength of light used in measurement of the spectrum and direction of polarization and, therefore, application of SERS including development and commercialization of the nano-biosensor is considerably affected. For this reason, a technique has been suggested, in the patent document 2 listed below, in which a hybrid structure of nanowire and nanoparticles is utilized to enhance SERS signals of such biomolecular as bio-extract and protein, DNA, repeatability of measurement and increase of sensitivity and reliability.
THE PRIOR ART
[0000]
Patent Document 1: JP Laid-open Patent Publication No. 2007-525662
Patent Document 1: JP Laid-open Patent Publication No. 2011-81001
[0010] It has, however, been found that the first mentioned conventional method has a problem in that it is difficult to isolate the protein and the protein segments in the sample and is therefore difficult to fix on the substrate, whereas in the last mentioned conventional method, no efficient utilization is made in quantitative determination of the protein in the sample. The present invention has been developed to substantially eliminate the above discussed problems and inconveniences and is intended to provide a biochip for use in SERS analysis, in which the protein in each of the samples can be easily adsorbed on the chip and in which quantitative determination of the specific protein, including DNA related substances, can be accomplished easily through laser irradiation and, also, to provide a method capable of identifying a particular disease from the profile of particular proteins including DNA related substances and analyzing the degree of progress. In the course of the present invention, the inventors of the present invention have found, as a result of studies committed with all their heats, that, where a metal complex is to be formed in an aqueous solution, the metal complex having a high complex stability constant, for example, a high complex stability constant defined by polydentate ligands, for example, two or more bidentate ligands, when it is deposited out by means of the reductive reaction taking place in the vicinity of equilibrium potential, the metal complex is deposited out on the metal substrate as a quantum crystal. The inventors of the present invention have also found that the metal complex exhibits such a physical property as to adsorb the proteins contained in a biological sample, enough to facilitate formation of a solid phased surface suitable for use in various detections. The inventors of the present invention have furthermore found that where metal of the metal complex is a plasmon metal, possibly because quantum dots in the order of nanometer (say, 5 to 20 nm) are regularly distributed to form quantum crystals (100 to 200 nm) of the internally capsulated metal complex, nanometric metal clusters so properly distributed exhibits a surface plasmon resonance enhancing effect as a metal against Raman light and, along therewith, the quantum crystals adsorb analyte to form electrical charge transfer complexes to thereby form the biochip suitable for use in SPR or SERS analysis.
[0011] The present invention has been found and then completed as a consequence that, when based on those findings as discussed above, a blood plasma is dropwise supplied onto the metal complex quantum crystal, the particular protein mass, including DNA related substances in the blood plasma, can be quantified and, yet, a significant difference is found in the particular protein masses, including DNA related substances, between normally healthy subjects and cancer affected patients and, therefore, identification of types of cancer and the degree of process of the cancer can be determined by means of the exhaustive analysis on Raman spectrum so obtained. If so required, the polarity or surface property of the quantum crystal may be adjusted, a biological sample selected from the group consisting of urea, blood, blood plasma, blood serum, saliva, seminal fluid, human waste, cerebral fluid, tear, mucin, exhaled component and so on is supplied dropwise, Raman spectrum is obtained by irradiating the protein in the biological sample, fixed on the quantum crystal, with laser light of a particular wavelength, and a biochip capable of achieving a disease analysis from the particular protein analysis including DNA related substances in the biological fluid, through analysis of the disease from exhaustive information such as, for example, the peak height of Raman spectrum so obtained, the peak integrated value, the peak representation time and so on. Accordingly, in the practice of the present invention, an aqueous solution of metal complex including a complex of plasmon metal selected from the group consisting of Au, Ag, Pt and Pd is dropwise applied onto a carrier metal having an electrode potential, which is less noble than complex metal, to thereby allow the metal complex to be precipitated on the carrier metal in the form of quantum crystal of nanometric size. The metal complex is so selected as to have a complex stability constant (log β) equal to or less noble (higher) than that expressed by the following formula which correlates with the electrode potential E of the carrier metal:
[0000] E °( RT/|Z|·F )In(β i )
[0000] (In this formula (1) above, E° represents the standard electrode potential, R represents a gas constant, T represents the absolute temperature, Z represents the ion valency, and F represents Faraday constant.)
[0012] The biochip of the present invention is preferably such that the surface property or the electric potential of the metal complex quantum crystals on the carrier metal is adjusted in dependence on an object to be detected in the aqueous solution prior to the precipitation or after the precipitation. The biochip of the present invention is preferably such that the metal complex quantum crystal in the carrier metal adjusts the surface property or the electric potential within the aqueous solution prior to precipitation or in accordance with an object to be detected subsequent to precipitation. In utilizing the antigen-antibody reaction, when the antigen or the antibody is mixed in the aqueous solution of metal complex to precipitate the quantum crystal, the quantum crystal can be dispersed in a manner similar to the ligand. It appears that the antigen or the antibody mixed in the aqueous solution of metal complex is precipitated in mixed form during the precipitation of the metal complex in a manner similar to the ligand of the metal complex. Accordingly, it can be used in detection using protein binding with blood plasma, detection using protein binding with calcium, and detection using protein binding with sugar (lectin) (infection disease and immunologic disease).
[0013] It has been found that when the alkaline treatment is carried out with the use of an aqueous solution of sodium hypochlorite used for an alkaline aqueous solution containing halogen ions after the precipitation of the quantum crystal of the metal complex, silver oxides including silver peroxide are aggregated as a result of self-assembly under the apparent influence of the electrode potential of the substrate in the case of silver thiosulfate quantum crystal and therefore meso-crystal, which is of a super structure in which they are arrayed in three dimension in neuron form when recrystallized
[0014] In the case of the metal complex being a silver complex, it has been found that the silver complex is formed as a result of the reaction between a silver complexing agent, having a stability constant (formation constant) (log β i ) which is 8 or higher, and silver halide. When the complexing agent is selected from the group consisting of thiosulfate, thiocyanate, sulfite salt, thiourea, potassium iodide, thiosalicylic acid salt and thiocyanuric acid salt, only a silver ion is not reduced, but the silver complex itself is precipitated as quantum crystals of the silver complex.
[0015] The complex has quantum dots of a nanometric size having an average particle size within the range of 5 to 20 nanometer and the size of the quantum crystals is within the range of 100 to 200 nm. The silver concentration of the metal complex in the aqueous solution is preferably within the range of 500 to 2,000 ppm.
[0016] As discussed above, it has been found that silver oxide containing silver peroxide, which is obtained by applying the alkali treatment (sodium hypochlorite) in the presence of halogen ions where the quantum crystal is silver thiosulfate, and the silver oxide meso-crystal, which is a super structure which is arrayed in three dimension in neuron form exhibit not only its structural characteristic, but also a negative charge in water, and adsorb cancer associated substances, which are positive charges, to form charge transfer complex and, also, the silver oxide meso-crystals are capable of changing into silver particles when irradiated with an exciting light, so that the surface plasmon enhancing effect can be obtained on the silver particles when irradiated with an exciting light such as laser. Accordingly, according to the present invention, the biochip provided with silver oxide meso-crystal can be used for Raman quantitative determination of the cancer associated substance.
[0017] With the biochip designed in accordance with the present invention, because of easiness of being charged with positive charge due to the characteristic of the metal complex, it is suited for use in adsorbing material propense to be charged with the negative charge in the aqueous solution. When an appropriate ligand is mixed in the aqueous solution of the metal complex at the time the metal complex is precipitated, the ligand can be mixed into the quantum crystal. By way of example, endotoxic can be detected if a limulus reagent (LAL reagent) mixed with the aqueous solution of metal complex of the present invention is precipitated onto the substrate as the quantum crystal. Also, in the utilization of properties of the quantum crystal precipitated on the substrate, a detecting regent for antibody or the like can be solid phased. On the other hand, in the biochip of the present invention, when the quantum crystal of the metal complex is treated with alkali in the presence of halogen ion, the quantum crystal can be recrystallized as a metal oxide crystal. Since when the quantum crystal of silver thiosulfate is treated with alkali in the presence of chlorine ion, mesocrystal of silver oxide including silver peroxide (AgO or Ag 2 O 3 ) is formed, it is susceptible to be charged with negative charge in the aqueous solution and, hence, quantification of the particular protein as well as DNA related substances in the biological fluid are realized to allow various diseases to be predictable and the degree of progress thereof can be affirmed. As a result of the presence of the significant difference in amount of protein in the blood plasma between the normal person and the cancer affected patient, identification of the type of cancer and the degree of progress thereof can be determined and, therefore, immediate diagnosis of the cancer, determination of the cancer treatment policy, determination of curative medicine and curative effect, determination of the metastasis of cancer, and determination of recurrence of cancer can become easily determined by means of this blood examination. Accordingly, if the biochip of the present invention is properly used and the use is made of other biological samples urea, blood, blood plasma, blood serum, saliva, seminal fluid, human waste, phlegm, cerebral fluid, tear, mucin, exhaled component and so on are used, the protein profile unique to the particular diseases is detected to give out information on the early discovery of the disease and the degree of progress of the disease through a simple examination.
[0018] The term “biological sample” referred to above and hereinafter is to be understood as meaning a sample including a sample containing an analyte containing hundreds of proteins such as biological fluid of a host. The sample may be provided for use directly in Raman analysis or may be pretreated so as to modify protein containing molecules in the sample or segmentalize, whichever the sample is prepared for each detection. Also, the analyte, which is a target to be measured, may be determined by detecting material capable of evidencing a target analyte such as, for example, particular binding pair members complemental to the analyte of the target to be measured which exists only when the analyte forming the target to be measured exists in the sample, but the disease is preferably identified by means of Raman spectrum analysis for exhaustively detecting the particular protein including DNA related substances. Accordingly, the material evidencing the analyte becomes an analyte that is detected during the assay. The biological sample may be, for example, urea, blood, blood plasma, blood serum, saliva, seminal fluid, human waste, phlegm, cerebral fluid, tear, mucin, or a exhaled component.
[0019] The term “protein” referred to above and hereinafter is to be understood as including peptide, polypeptide and a protein containing analyte such as protein, antigen, sugar protein, riboprotein and others.
[0020] In one embodiment of the present invention, a method is provided for securing information on protein composition from a composite biological sample such as, for example, a patient sample. The protein in the sample may be arbitrarily modified with the use of a medical agent selected from the group consisting of a reducing agent, a surfactant, chaotropic salt and others. Although general chemical substances that can be used to reduce the disulfide binding may include DTT, DTE, 2-mercaptoethanol and so on, in the practice of the present invention there is no reason to limit to the use thereof. Representative surfactants capable of being used to modify the protein may include dodecyl sodium sulfate (SDS), Triton X 100 (R) , Tween-20 (R) and so on, but there is no reason to limit to the use thereof in the practice of the present invention. Yet, although typical chaotropic agents that can be used to modify the protein may includes GuSCN, NaSCN, GuClO4, NaclO4 and urea, there is no reason to limit to the use thereof in the practice of the present invention. The solid protein such as segments and so on can be modified with the use of a cutting agent or chemical serine-protease such as, for example, trypsin for digesting the protein. The protein may be of a native structure (not yet modified) for the purpose of Raman analysis or SERS analysis.
[0021] The metal complex quantum crystal of the present invention is precipitated on the metal to form the biochip and, therefore, it appears that the metal nanometric dots that function as metallic nanoparticles are apt to be ionized and, therefore, it is held in contact with the reagent (target molecule) within the aqueous solution. Accordingly, the biochip suitable for use in measurement of the surface enhanced Raman scatterings (SERS) can be suitably employed since it has a surface plasmon resonance enhancing effect, which is exhibited by the metal nanoparticles that are regularly arrayed, and an ionic metal property which forms the charge transfer complex together with target molecules (the inventors of the present invention call “it “submetallic property” because of the metallic property and the ion property both possessed by the biochip of the present invention.)
[0022] Metal complex to form a quantum crystal is selected to have a complex stability constant (log β) of the formula (I) to correlate the electrode potential E of the supported metal.
[0000] E °( RT/|Z|F )ln(β i ) Formula (I)
[0000] Where E° is the standard electrode potential, R is the gas constant, T is absolute temperature, Z is the ion valence, F represents the Faraday constant.)
In case that the metal complexes can be selected from the group consisting of plasmon metals such as Au, Ag, Pt and Pd, the plasmon metals have a function of localized surface plasmon resonance enhancement effect for the Raman light. In particular, when the metal complex is a silver complex, the complex may be formed by reaction of silver complexing agent having a stability constant (formation constant) (log β i ) of 8 or more with a silver halide, where a silver chloride may be preferably selected as the halide and the complexing agent may be preferably selected from the group consisting of thiosulfate salt, thiocyanate salt, sulfite salt, thiourea, potassium iodide, thiosalicylic acid salt, and thiocyanuric acid salt.
[0023] In case of the silver complex, the resulting quantum crystal has quantum dots made of nano-cluster having average diameter of 5˜20 nm, so that the size of the quantum crystal will be in a range of 100 to 200 nm.
[0024] The concentration of the metal complex in the aqueous solution should be determined depending on the size of the quantum crystals mainly, and the concentration of a dispersing agent had better to be considered when using it, Typically, although the metal complex in the aqueous solution can be used in the range of 100 ppm to 5000 ppm, in order to prepare nano-sized particles called as the nano-cluster, it may be used preferably in a range of 500 to 2000 ppm depending on the functionality of the ligand of the metal complex
[0025] The quantum crystals formed on a metal substrate or metal particles are believed to likely have a positive polarity in an aqueous solution as a metal complex crystals. Therefore, in order to adsorb the protein in a biological sample on a solid phase, so the solid phase should be subject to an alkali treatment in the presence of halide ions and to adjust the polarity, for example it can be carried out by dropping sodium hypochlorite solution of pH11 or more thereon. After the treatment, the quantum crystals is re-crystallized not only to have a negative polarity in an aqueous solution and also to form a meso-crystalline comprising silver oxide including silver peroxides, where proteins in a sample are possible to facilitate the immobilization on the bio-chip.
[0026] Proteins caused from the disease are contained in biological samples of urine, blood, plasma, serum, saliva, semen, slops, sputum, cerebral spinal fluids, tears, mucus, breath components and so on. The samples are diluted by aqueous or hydrophilic solvents to an appropriate concentration before dipping.
[0027] The total protein concentration in a biological sample can be measured and determined from the Raman spectrum obtained by irradiating a laser beam of a specific wavelength. FIG. 3 is a Raman spectrum wherein a serum sample of each colon cancer patients is diluted 10-fold, 100-fold, 500-fold, 1000-fold and 10000-fold with pure water and measured by 633 nm laser (30 mW), so as to obtain peak rising value (PSV) and peak integration value, which value tend to change with concentration. Therefore, it is understood that it is possible to perform a quantitative analysis of the total protein in the serum.
[0028] Therefore, it is possible to analyze the identification and progress of cancer from information such as the peak height, the peak integral values and the peak onset time of the resulting Raman spectrum. FIG. 1 shows a peak calculation method of Raman waveform, wherein from the spectrum of Raman scattering by 633 nm laser of human serum samples it is confirmed to form the peak of the scattering intensity in the vicinity of 1350 cm −1 and 1550 cm −1 . Thus, on the basis of average value (m) between 800 cm −1 (a) and 2000 cm −1 (b) of scattering intensity the (p-m) peak rising value is defined as (Shifting Peak Value PSV) These peaks rise value and peak integral value are important in view of the cancer related substances in human serum, because it is possible to be an indicator of the identification and progression of cancer in conjunction with peak onset time.
BRIEF DESCRIPTION OF DRAWINGS
[0029] FIG. 1 shows a peak calculation method of the Raman wave, where spectra of the Raman scattering by 633 nm laser of human serum samples indicates the formation of a peak of scattering intensity in the vicinity of 1350 cm −1 and 1550 cm −1 .
[0030] FIG. 2A is a Raman spectral diagram of a sample by adjusting the sera obtained from 12 cases of stomach cancer patients.
[0031] FIG. 2B is a Raman spectral diagram of a sample by adjusting the sera obtained from 12 cases of colorectal cancer patients.
[0032] FIG. 2C is a Raman spectral diagram of a sample by adjusting the sera obtained from 12 cases of benign disease patients.
[0033] FIG. 2D is a graph showing a comparison of Raman scattering peak rising value of stomach cancer, colorectal cancer, and benign disease sample.
[0034] FIG. 3 is the Raman spectrum showing the relationship between diluted samples and the Raman scattering intensity where the diluted samples are obtained from 12 cases of colon cancer patients, which shows that the scattering intensity peak rising value and the sample concentration are correlative each other.
[0035] FIG. 4 is an explanatory diagram showing a making procedure of the present inventive new SERS substrate shown in Example 1, wherein an upper left photograph shows a substrate of Mytec Co. Ltd. with the SEM image.
[0036] FIG. 5 is a photograph showing various SEM images of the nano-particle aggregate (quantum crystal) prepared in Example 1.
[0037] FIG. 6 is a photograph showing an enlarged SEM image of a nanoparticle.
[0038] FIG. 7 is a photograph showing the relationship between quantum crystal shapes and standing times after dropping on the phosphor bronze substrate.
[0039] FIG. 8 is a graph showing a result of EDS spectra analysis of quantum crystals (elemental analysis).
[0040] FIG. 9 is a photograph showing SEM image of quantum crystals alkali-treated in the presence of a halogen ion (Sodium hypochlorite treatment).
[0041] FIG. 10A is a photograph showing needle-like crystals of the alkali-treated quantum crystals.
[0042] FIG. 10B is a photograph showing a rugby ball-shaped mass in the. needle-like crystals.
[0043] FIG. 10C is a graph showing a result of EDS spectra of large mass (elemental analysis).
[0044] FIG. 11 is functional illustration views showing a state of the methylated free DNA (a) and a state of acetylated DNA (b).
[0045] FIG. 12 is a view (top) of SEM image showing a re-crystallized substrate which is the quantum crystal substrate alkali treated in the presence of a halogen ion (Sodium hypochlorite treatment) (top view) and a graph (below) showing a result (elemental analysis) of the EDS spectra of the re-crystallized substrate.
[0046] FIG. 13 is a graph showing a result of XPS measurement of the alkali-treated recrystallization substrate.
[0047] FIG. 14 is a graph showing a result of XPS measurements after etching the surface of the recrystallization substrate.
DESCRIPTION OF EMBODIMENTS
[0048] Hereinafter, embodiments of the present invention will be explained, referring to the attached drawings,
Example 1
[0049] As shown in FIG. 4 , an aqueous solution containing 1000 ppm of silver thiosulfate was prepared and the 1 drop was added dropwise on a phosphor bronze plate. After standing for about 3 minutes, the solution on the plate was blown off. On the plate, quantum crystals were obtained as shown in the SEM image at the right side of FIG. 4 . FIG. 5 is a photograph showing various SEM images of the nano-particle aggregate prepared in Example 1 (quantum crystal), and FIG. 6 shows an enlarged SEM image of nano-particles where there were thin hexagonal columnar crystals of 100 nm more or less and having an unevenness surface of several nm order. We could not find out any specific facets of metal nano-crystals in the quantum crystals. FIG. 7 is a photograph showing the relationship between quantum crystal shapes and the standing time after dropping onto the phosphor bronze substrate, where it is recognized that firstly, a hexagonal quantum crystal is produced and then growing while maintaining the crystal shape.
[0050] FIG. 8 is a graph showing a result of EDS spectra (elemental analysis). of the quantum crystals where not only silver but also elements derived from complex ligands can be detected in case of the quantum crystal on the phosphor bronze substrate, while only silver can be detected in the case of the quantum crystals formed on a copper plate by using 1000 ppm of silver thiosulfate in aqueous solution and keeping it for the standing time of 3 minutes after dropping onto the copper substrates.
[0051] (Discussion on Formation of the Quantum Crystal)
[0052] In case of 1000 ppm of silver thiosulfate complex in an aqueous solution, hexagonal column crystals of 100 nm more or less, are formed for the standing time of 3 minutes after dropping it onto a phosphor bronze plate, where it is confirmed that irregularities of several nm order are found on the hexagonal column quantum crystals from the SEM images ( FIGS. 4, 5 and 6 ). and any specific facets derived from metal nano-crystals are not found, while the EDS elemental analysis shows silver and elements derived from the complexing ligand. Accordingly, it can be estimated from the above analysis, that the whole particles show nano-crystals of silver complex and also the unevenness appearance on the surface may be caused by the formation of spread quantum dots made of silver clusters in the complexes. From the aspect of phenomenon that the silver complex quantum crystals of the present invention can be formed on a phosphor bronze plate, while silver nano-particles alone can be deposited on the copper substrate, it is estimated that, as the equilibrium potential of the silver thiosulfate complexes is 0.33 which is equivalent to the copper electrode potential with 0.34, there is deposited only silvers with 0.80 on the copper substrate. On the other hand, in case of a phosphor bronze plate with the electrode potential of 0.22, which is slightly less noble than that of the copper so that silver complex crystals seem able to be precipitated. The concentration of the silver complex in the aqueous solution should be in a dilute region of 500˜2000 ppm, 2) the electrode potential of the metal substrate with respect to the equilibrium potential of the metal complex solution is slightly less noble, 3) the metal complex should be deposited by the electrode potential difference between the metal substrate and the metal complex. Further, in case of 1000 ppm of thiourea silver complex in aqueous solution, the same function can be observed.
Example 2
[0053] On a substrate of silver thiosulfate quantum crystal made by using the phosphor bronze plate in Example 1, an aqueous solution of sodium hypochlorite having pH11 is dropped. After dropping of the aqueous solution, the solution is kept on the substrate and is brown off to prepare a bio-chip for SERS. On the other hand, the sera obtained from 12 cases of gastric cancer patients, the sera obtained from 12 cases of the colorectal carcinoma patients and the sera obtained from 12 cases of benign disease patients, all of them are diluted 10 times to prepare testing samples, which are subjected to a measurement of Raman spectra with irradiated with 633 nm laser light. There are observed much correlation between the degree of progress and the peak rise values as well as the peak integral value in case of gastric cancer and colon cancer. In addition, in the case of gastric cancer, the peak became to develop in the Raman spectrum after one minute of the laser irradiation, while in the case of colon cancer the peak became to develop in the Raman spectrum after 2-3 minutes after laser irradiation. Also, FIG. 2D is a graph showing a comparison of the Raman scattering peak rising values concerning gastric cancer, colon cancer and benign disease. The peak of the gastric cancer samples and colon cancer samples are found to be significantly higher than that of the benign disease samples. While it is difficult to find the difference between the gastric cancer sample and the colon cancer samples concerning the peak rise value, it can be recognized to show a possibility to identify both cancers by considering the peak expression times and the peak integral value. Here, the free DNA to be detected is a DNA wound around the protein called histones, which wound unit structure (1 set) is called a nucleosome and the structure which comes to a string shape of nucleosome gathered is called a chromatin (fibers). And, when the cells were into a cancerous state and divided repeatedly, DNA becomes to wrap around the histone not so as to come out the genes (tumor suppressor gene) inconvenient to increase the cancer and the DNA winding onto the histone becomes more tightly by methylation not so as to make the DNA loosen from the histones easily. Usually the histones are charged as (+), while the DNA is charged as (−), so that the two are stuck like a magnet and the methylation makes the two not to loosen easily where the methylated DNA wound around the histones is charged to the (+) state (see FIG. 11( a ) ). On the other hand, acetylation makes histone changed into charge (−), so that DNA of (−) becomes to act repulsively to the histones changed into the (−) state by the acetylation, resulting in expression of genes due to the unwound mechanism of the ‘thread’ of DNA from the histones (see FIG. 11( b ) ). Therefore, in order to selectively adsorb or trap the free DNA derived from cancer cells as the DNA wound around the histones, the substrate to absorb or trap the cancer related substances (+) in the sample is considered to have preferably a state of charge (−) in the sample for analysis.
[0054] (Discussion on the Meso-Crystal of Silver Oxide Compound: Part 1)
[0055] The quantum crystal substrate is subjected to a treatment of dropping 5% sodium hypochlorite solution thereon and the dropped solution is removed off 2 minutes later to obtain crystals having structures shown in FIG. 12 , where needle-shaped crystals and large clumps such as rugby ball-like mass are observed, so that the respective compositions are subjected to analyzation at EDS spectra (elemental analysis). After a result of the analysis, the needle-like crystals are both considered to consist of a composite crystal of silver oxide and silver chloride, from the following reaction formulas and the result of FIG. 12 does not show any chlorine and shows that the silver and oxygen is dominant.
[0000] Na 2 S 2 O 3 +4NaClO+H 2 O→Na 2 SO 4 +H 2 SO 4 +4NaCl (1)
[0000] Ag + +NaCl→AgCl+Na + (2)
[0000] Ag + +3NaOCl→2AgCl+NaClO 3 +2Na + (3)
[0000] Ag + +OH—→AgOH (4)
[0000] 2Ag + +2OH→Ag 2 O+H 2 O (5)
[0000] Thus, although it is considered that silver ions and thiosulfate ions are important in the formation of meso-crystal according to the present invention by alkaline oxidation reaction in the presence of chloride ions and, although the silver oxide is formed according to a conventional reaction, it is surprisingly estimated that silver peroxide are predominantly formed from the following XPS measurement.
[0056] (Discussion of the Meso-Crystal of Silver Oxide Compound: Part 2)
XPS Measurement:
[0057] The aqueous sodium hypochlorite was added dropwise to the quantum crystal substrate prepared as the above for 2 minutes, to make a re-crystal substrate, which is subjected to a XPS analysis (using models: ULVAC-PHI (Ltd.)/PHI5000 Versa Probe II (scanning X-ray photoelectron spectroscopy) for Ag and O by XPS measurement without etching. In addition, for comparison, Ag in the powder of silver chloride and the powder of silver oxide were measured. On the other hand, the recrystallized substrate was subjected to XPS measurement of Ag and O after etching for 5 minutes with an argon gas cluster ion gun. If the XPS measurement results of FIGS. 13 and 14 will be combined with the results of EDS according to FIG. 12 , the peak in the vicinity of 529 eV is the peak derived from silver peroxide (AgO), while the peak in the vicinity of 530 eV is the peak derived from silver oxide (Ag 2 O). Further, If it is etched, the oxygen content decreases, while the 0 peak derived from the silver peroxide (AgO) in the vicinity of 529 eV is still greater than the peak derived from the silver oxide in the vicinity of 530 eV in case of etching, so that it is recognized that the silver peroxide was produced in the vicinity of the substrate. It is assumed that the electrode potential of the substrate and the catalytic action are affected. to the meso-crystal formation The EDS measurement was carried on the above-mentioned re-crystal substrate by using a JEOL Ltd,/JSM-7001F (field emission scanning electron microscope analysis). In addition, even if the aqueous solution selected from the group consisting of hypochlorous acid, 0.01 N sodium hydroxide, 0.01 N hydrochloric acid and 0.1 molar sodium carbonate would be used, any result similar to be treated with sodium hypochlorite was not obtained, Thus, it is believed that the formation of the needle-like crystals are caused by the above reaction in the presence of silver ions and thiosulfate ions. While the silver oxide is induced into negatively charged in an aqueous solution, it is reduced by the light to deposit metallic silver. Further, since silver peroxide shows more remarkable in the above tendency than silver oxide, it is possible to adsorb cancer related substances having a positive charge, resulting in occurrence of the surface plasmon enhancement effect between the trapped cancer related substance and the silver particles.
INDUSTRIAL APPLICABILITY
[0058] Thus, according to the present invention, by using the other biological sample selected from the group consisting of urea, blood, blood plasma, blood serum, saliva, seminal fluid, human waste, cerebral fluid, tear, mucin, exhaled component and so on, it is possible not only to detect protein profiles specific to the particular diseases and provide an early stage diagnosis and information of the disease progress by simple method, but also to selectively trap each of disease related substances, the judgement of each of diseases can be made by the measurement of Raman spectra. | Object: To provide a biochip for use in exhaustive analysis of a particular protein including DNA (deoxyribose nucleic acid) in a body fluid through Raman quantitative analysis.
Resolving Means: Aqueous solution of metal complexes including plasmon metal selected from the group consisting of Au, Ag, Pt and Pd is supplied dropwise onto a carrier metal having an electrode potential of metal less noble than complex metal, followed by precipitation of nanometric quantum crystals from the metal complex on the carrier metal, the metal complex being so selected as to have a complex stability constant (log β) that is expressed by the following equation (I) correlating with the electrode potential E of the carrier metal:
E °=( RT/|Z|·F )In(β i ) (I)
(wherein E° represents the standard electrode potential, R represents a gas constant, T represents the absolute temperature, Z represents the ion valency, and F represents the Faraday constant), the surface property of the metal complex quantum crystals on the carrier metal being subsequently adjusted in dependence on an object to be detected in the aqueous solution prior to the precipitation or after the precipitation. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to vehicle suspension and, in particular, is concerned with an air spring module for use with a damper.
2. Description of the Related Art
Automotive suspension struts, such as used in MacPherson-type suspensions, are commonly constructed with either coil springs or air springs mounted coaxially about the strut. A particular problem is encountered by front suspension struts which are mounted to the front steerable wheels. When the wheels are steered, the spring undergoes a twisting movement as the strut body rotates with the wheel. Such twisting undesirably changes the characteristics of the coil spring. To solve the torsional twist of coil springs, a bearing assembly is placed between the vehicle body and a mounted piston rod of the strut to allow the strut to rotate relative to the body.
Air springs also are mounted about suspension struts alone or in combination with coil springs.
It is desirable when incorporating an air suspension spring on a MacPherson strut assembly to allow for replacement of the MacPherson strut without removal or disassembly of the air spring. In order to do this, the air spring should be detachable with respect to the strut body and the vehicle body.
SUMMARY OF THE INVENTION
The present invention includes an air spring module mounted about a suspension damper. The module includes means for removably securing the air spring to the damper body and a bearing and mounting assembly for permitting the rotation of the air spring with respect to the vehicle body as the damper body rotates during steering. The module can be used with a sealed damper.
In a preferred embodiment, an air spring module is constructed and arranged to be removably mounted between a damper and a vehicular body. The module includes a bored contact piston which is slip fitted over a reciprocable piston rod of the damper. A retaining ring releasably locks the contact piston to the damper, and 0-ring seals provide a seal between the contact piston and the damper. An air sleeve is secured at its lower end to the contact piston and is secured at its upper end to a canister. A bearing assembly and mount rotationally and removably secures the canister to the body.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a longitudinal sectional view of an air spring module according to the present invention mounted at its upper end to a vehicle body and removably secured to a damper at its lower end.
FIG. 2 is an enlarged view of a portion of the assembly illustrated in the circle of FIG. 1.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
An air spring module indicated generally at 10 is illustrated in FIG. 1. As described below, the module 10 is removably mounted on a damper 100. The damper 100 includes an outer reservoir tube 102 closed at its upper end by a seal cover 104. An upstanding neck 106 of the seal cover 104 receives a reciprocable piston rod 108 extending from the damper 100. The lower end (not illustrated) of the damper 100 is mounted to a wheel assembly (not illustrated) in a conventional manner.
The module 10 includes a profiled contact piston 12 which is generally cylindrical and has an increased diameter at its lower portion. The piston 12 includes a stepped bore having a large diameter portion 14 and a small diameter portion 16. The reservoir tube 102 is received in the large diameter portion 14 and the neck 106 and piston rod 108 fit in the small diameter portion 16. A retaining sleeve 18 is press fitted into the small diameter portion 16 and includes an annular stop 20 which engages the end surface of the neck 106. A cup 22 is retained to the sleeve 18 by a crimped flange 24 and secures an elastomeric compression bumper 26 coaxially mounted about the piston rod 108.
An elastomeric air sleeve 28 is attached to the outer circumference of the contact piston 12 by a clamp or retainer 30. A rolling lobe 32 is formed in a portion of the sleeve 28 which travels along the contact piston 12 in a well-known manner. The upper portion of the sleeve 28 is secured to a partially-cylindrical canister 34 by a clamp or retainer 36. The canister 34 is welded to a lower bearing retainer 38. An elastomerically-isolated bearing assembly 40 is provided between the lower bearing retainer 38 and an upper bearing retainer 42. An elastomeric mount 44 includes a cylindrical sleeve 46 which is fitted over a stepped portion 110 of the piston rod 108. A metallic ring 48 is provided about the mount 44 and welded to the lower bearing retainer 38 to secure the mount 44. A lower rate washer 50 is secured to the sleeve 46 at a lower surface of the mount 44. A plate 52 is connected to the lower bearing retainer 38 by a retainer ring 54 received in a groove in the outer circumference of a neck portion 56 of the lower bearing retainer 38. The plate 52 includes a plurality of downwardly projecting preloaded rubber pads 58. The pads 58 rest on a plurality of thrust washers 60, preferably formed from low friction materials such as polytetrafluoroethylene. The thrust washers are concentrically mounted about the neck 56 of the lower bearing retainer 38 and are held in place by a support 62 secured to the upper bearing retainer 42.
The module 10 described above can be mounted on any type of damper, including hydraulic and pneumatic dampers. To assemble the module 10 in a vehicle, the contact piston 12 is fitted over the piston rod 108 and reservoir tube 102 via the stepped bore. A pair of O-ring seals 64, 66 are provided in a first circumferential groove 112 in the neck 106 of the seal cover 104 to provide a seal between the sleeve 18 and the neck 106. A retainer ring 68 is mounted in a second circumferential groove 114 of the neck 106 and is initially compressed as the sleeve 18 is slid over the neck 106. A complementary groove 70 is provided in an inner surface of the sleeve 18 so that the retainer ring 68 springs outwardly and fits snugly into the groove 70 when the contact piston 12 is in its proper position. This construction provides a quick and removable connection between the lower end of the module 10 and the damper 100.
A fastener 72 removably mounts the contact piston 12 to a support plate 116 welded to an outer surface of the reservoir tube 102. The damper 100 and air spring module 10 are then inserted upwardly through an opening 118 in a vehicle body 120. Fasteners 122, 124 are inserted through openings in the body 120 and threaded into complementary nuts 74, 76 welded to a lower surface of the upper bearing retainer 42. In this manner, the upper end of the air spring module 10 is removably connected to the body 120. A conduit assembly 126 and a washer 128 are secured to the upper end of the piston rod 108 by a nut 130. The conduit assembly 126 is in fluid communication with a compressor (not illustrated) to operate the air spring module 10 as desired. The compressor can include valving to control the flow of fluid into and out of the conduit assembly 126.
An axial bore 132 is provided in the piston rod 108 beginning at its upper end to a point below the lower rate washer 50. A plurality of radial bores 134 are provided at the lower end of the axial bore 132 to provide a fluid flow path from the conduit assembly 126 to an air chamber 78 formed by the air sleeve 28. During use, a control system (not illustrated) can add air to the air chamber 78 through the axial and radial bores 132, 134 as desired. The module 10 is effectively sealed from the damper 100.
As the damper 100 is turned at its lower end from a steering input, the contact piston 12 and attached air sleeve 28 and lower bearing retainer 38 rotate with the damper 100. The bearing assembly 40 permits relative rotation of the lower bearing retainer 38 with respect to the upper bearing retainer 42 and the vehicle body 120. The preloaded rubber pads 58 provide isolation and support against the thrust washers 60 for the module 10 as the lower bearing retainer 38 rotates.
It will be appreciated that the air spring module 10 can be used with any type of damper, including shock absorbers and struts. The module 10 is easily removed from the damper 100 by removing the fastener 72 and forcing the contact piston 12 upwardly away from the reservoir tube 102. At this point, the retainer ring 68 is compressed into the groove 114 until the sleeve 18 clears the neck 106 of the seal cover 104. Removing fasteners 122, 124 from the body 120 frees the upper end of the air module 10. Therefore, if a damper 100 becomes defective, it will be necessary only to replace the damper 100, and the air spring module 10 can be retained. On the other hand, if the air spring module 10 is damaged, e.g., if the air sleeve 28 becomes punctured, the damper 100 can be easily removed, permitting the air spring module 10 to be replaced.
Although the present invention has been described with reference to preferred embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention. | An air spring module is constructed and arranged to be removably mounted between a damper and a vehicular body. The module includes a bored contact piston which is slip fitted over a reciprocable piston rod of the damper. A retaining ring releasably locks the contact piston to the damper, and O-ring seals provide a seal between the contact piston and the damper. An air sleeve is secured at its lower end to the contact piston and is secured at its upper end to a canister. A bearing assembly and mount rotationally and removably secures the canister to the body. | 1 |
REFERENCE TO RELATED APPLICATIONS
[0001] This application is a national stage application under 35 USC 371 of International Application No. PCT/GB06/004681, filed Dec. 14, 2006, which claims the priority of United Kingdom Application No. 0602075.4, filed Feb. 2, 2006, the contents of both of which prior applications are incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to drying apparatus. Particularly, the invention relates to drying apparatus including a filter unit for removing particulates and bacteria from a waste liquid such as water.
BACKGROUND OF THE INVENTION
[0003] Conventional arrangements for collecting and removing waste water from drying apparatus such as hand dryers are well known from, for example, U.S. Pat. No. 5,459,944. Waste water is collected via a duct or similar and transferred to a drip collector for subsequent manual removal. Such storage of waste water is unhygienic, may lead to the spread of bacteria and requires regular maintenance to empty the drip collector and maintain a sanitary environment.
[0004] The addition of an antibacterial water absorption sheet with a large surface area to encourage evaporation is known from JP 11-18999 A. This counters some of the problems of bacterial infestation and results in less frequent emptying of a water collector. However, particulate matter will be deposited on the sheet, and this will affect the performance of the machine over time and require frequent cleaning.
SUMMARY OF THE INVENTION
[0005] It is an object of the present invention to provide drying apparatus which is capable of filtering and sterilising liquid more efficiently and reliably than prior art apparatus.
[0006] The invention provides drying apparatus comprising an outer case, a portion of the outer case defining a cavity in which articles can be dried, an outlet disposed at the lower end of the cavity and a filter unit arranged downstream of the outlet, wherein the filter unit comprises a particulate filter and a sterilising filter. By providing a filter unit comprising a particulate filter and a sterilising filter, solid matter and bacteria can be removed from the waste liquid. This results in a hygienic and sanitary waste liquid output from the filter unit.
[0007] Preferably, the sterilising filter is located downstream of the particulate filter. By this arrangement, the particulate filter can remove some solid material and larger particulates from the waste liquid to prevent the sterilising filter from clogging.
[0008] Preferably, the filter unit further comprises flow directing means for guiding liquid through the filter unit. By providing flow directing means, the liquid can be directed to flow through the sterilising filter. The flow directing means allow efficient use of the sterilising filter ensuring that the water leaving the filter unit has been sufficiently treated.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] An embodiment of the invention will now be described with reference to the accompanying drawings, in which:
[0010] FIG. 1 a is a perspective view of a hand dryer according to the present invention;
[0011] FIG. 1 b is a side view of the hand dryer of FIG. 1 a;
[0012] FIG. 2 is a section through the hand dryer of FIG. 1 a showing a filter unit;
[0013] FIG. 3 is an enlarged version of part of FIG. 2 showing the internal workings of the hand dryer and the filter unit in greater detail;
[0014] FIG. 4 is a perspective view of a liquid treatment module including the filter unit removed from the hand dryer of FIG. 1 a;
[0015] FIG. 5 a is perspective view from above of the hand dryer of FIG. 1 a showing the liquid treatment module partially removed from the hand dryer; and
[0016] FIG. 5 b is a perspective view from below of the hand dryer of FIG. 1 a showing the liquid treatment module partially removed from the hand dryer.
DETAILED DESCRIPTION OF THE INVENTION
[0017] FIGS. 1 a and 1 b show a hand dryer 10 according to the present invention. The hand dryer 10 includes an outer case 12 , a front wall 14 a , a rear wall 14 b , two side walls 14 c , 14 d and a cavity 16 . The rear wall 14 b may include elements suitable for attaching the hand dryer 10 to a wall surface or other suitable fixture. Elements for connecting the hand dryer 10 to a power source may also be included.
[0018] The cavity 16 is defined by opposing arcuate front and rear walls 16 a , 16 b . The cavity 16 is open at its upper end 18 , and the dimensions of the opening are sufficient to allow a user's hands (not shown) to be inserted easily into the cavity 16 for drying. A high-speed airflow is generated by a motor unit having a fan (not shown). The motor unit and fan are located inside the outer case 12 . The high-speed airflow is expelled through two slot-like openings 20 disposed at the upper end 18 of the cavity 16 to dry the user's hands. These features are not material to the present invention and will not be described any further here. The cavity 16 is open at the sides as can be seen in FIGS. 1 a and 1 b.
[0019] As can be seen from FIG. 2 , a drain channel 22 is located at the lower end 24 of the cavity 16 . The drain channel 22 is delimited by the lower edges of the front wall 16 a and the rear wall 16 b of the cavity 16 and slopes downwardly towards one side of the cavity 16 . An outlet 26 is located in the drain channel 22 . The outlet 26 can take any suitable form. In this embodiment, it comprises a circular aperture with a central plug 26 a . The outlet 26 and plug 26 a delimit a narrow, annular opening.
[0020] Referring to FIGS. 2 and 3 , a chamber 40 is formed in a lower part of the outer case 12 below the cavity 16 . The chamber 40 is delimited by a plurality of chamber walls 40 a and has an open lower end. A liquid treatment module 30 is located in the chamber 40 and is held in place by clips, quarter turn fastenings or other fastening means (not shown).
[0021] Referring to FIGS. 3 and 4 , the liquid treatment module 30 includes a filter unit 200 . The filter unit 200 is designed to filter particulates and impurities from the water, and to kill bacteria in the water. A filter inlet 202 is located at the upper end of the filter unit 200 and communicates with the outlet 26 . A sump 204 is located downstream of the filter inlet 202 . The sump 204 has a base 204 a . A wall 206 of the sump forms a weir 206 a . The height of the weir 206 a determines the maximum level of liquid that can be contained within the sump 204 . A filter outlet 208 is delimited by the weir 206 a , the wall 206 of the sump 204 and the outer walls 210 of the filter unit 200 . The filter outlet 208 provides an outlet for water flowing over the weir 206 a.
[0022] A partition 212 extends from the upper portion of the filter unit 200 adjacent the filter inlet 202 into the sump 204 . The partition 212 extends partially into the sump 204 such that the distal end 212 a of the partition 212 is spaced from the base 204 a of the sump 204 . The partition 212 is arranged such that the volume of a first region 204 b of the sump 204 beneath the filter inlet 202 is greater than a second region 204 c of the sump 204 adjacent the weir 206 a.
[0023] A sterilising filter 214 is located at the base 204 a of the sump 204 . The sterilising filter 214 consists of particles of an iodine-loaded resin. The resin is loaded at a concentration of 500 g/l. In this embodiment, the volume of the sterilising filter 214 is 50 ml. The iodine-loaded resin acts as a sterilising compound to kill any bacteria present in the water. The particles of the sterilising filter 214 are substantially spherical and have dimensions in the range of 0.1 to 2 mm (average particle size 0.8 mm). The sterilising filter 214 is dimensioned such that the distal end 212 a of the partition 212 extends partially into the sterilising filter 214 .
[0024] A particulate filter 216 is located above the sterilising filter 214 and comprises glass beads with diameters of 4 mm. The particulate filter 216 is located on top of the sterilising filter 214 in the first region 204 b beneath the filter inlet 202 which is bounded by the partition 212 and the sump 204 . The particulate filter 216 has a volume of 10 ml. Further, the particulate filter 216 operates as a pre-filter, preventing larger particles of solid matter (in particular soap) from blocking the sterilising filter 214 . In order to improve performance, the area of the bed of the particulate filter 216 and sterilising filter 214 is maximised. A large bed area reduces the pressure drop across the filters and increases the resistance of the filters to fouling and becoming blocked.
[0025] Both the sterilising filter 214 and the particulate filter 216 are located in the sump 204 below the maximum level of liquid that can be contained in the sump 204 . This means that, once the level of liquid in the sump 204 has reached the maximum, operational, level, the sterilising filter 214 and the particulate filter 216 are completely submerged in the water. This is beneficial because the sterilising filter 214 is prone to cracking and forming air pockets if it is permitted to dry out once it has become wetted. By keeping the sterilising filter 214 continuously wetted, this problem is avoided. In addition, this configuration ensures that the water flow is well distributed. Further, the maximum level of liquid should be far enough above particulate filter 216 to allow the head of water to apply pressure on the bed of the filters.
[0026] The liquid treatment module 30 further includes a liquid dispersion unit 35 located below the filter unit 200 . The liquid dispersion unit 35 is arranged to receive water from the filter outlet 208 . An exhaust conduit 37 located within the liquid dispersion unit 35 provides a communication path from the liquid dispersion unit 35 to the outside of the outer case 12 of the hand dryer 10 . The liquid dispersion unit 35 further includes a collector 100 for collecting water from the filter outlet 208 . The collector 100 has a base 100 a . A high frequency agitator in the form of a piezo-electric device 102 is located at the base 100 a . A fan 104 is supported on one of the chamber walls 40 a . The fan 104 is located outside the chamber 40 separate from the liquid treatment module 30 . The fan 104 is configured to direct an airflow into the collector 100 through an aperture 38 provided in the liquid treatment module 30 .
[0027] In use, the water removed from a user's hands during the drying process flows down the front wall 16 a and the rear wall 16 b of the cavity 16 and into the drain channel 22 disposed at the lower end 24 of the cavity 16 . The drain channel 22 collects and guides the water towards the outlet 26 .
[0028] Upon entering the outlet 26 , the water passes into the filter unit 200 through the filter inlet 202 (see arrow A). The water falls onto the particulate filter 216 (arrow B) and spreads evenly across the surface of the particulate filter 216 . As the water moves down through the beads of the particulate filter 216 under the influence of gravity, larger particles of dirt and debris will be left behind in the particulate filter 216 . When the water reaches the sterilising filter 214 (arrow C), the majority of the solid particulates in the water will have been removed by the particulate filter 216 .
[0029] The sterilising filter 214 sterilises the water by deactivating bacteria in the water. The iodine-loaded resin releases iodine into the water at a rate of 1 to 5 parts per million (ppm). Iodine is a strong oxidant and hence acts as broad spectrum antimicrobial. The water flows down through the sterilising filter 214 , is sterilised and is then deposited in the bottom of the sump 204 . This process continues and the volume of water collected in the sump 204 increases until it reaches the maximum level permitted by the weir 206 a . Up until this point, the water levels either side of the partition 212 experience an equal force due to atmospheric pressure. However, if more water is introduced through the filter inlet 202 , the increased head of water in the first region 204 b will cause an imbalance in the forces acting on the water levels either side of the partition 212 . The effect of this is for the mass of the added water to apply a force downwardly on the water in the sump 204 . This causes a net movement of water in the direction shown by the arrow D. The partition 212 directs the flow of water down towards the base 204 a of the sump 204 , down through a part of the sterilising filter 214 located in the first region 204 b of the sump 204 , and back up through another part of the sterilising filter 214 located in the second region 204 c of the sump 204 to the weir 206 a . Therefore, the partition 212 forces the water to follow a convoluted path from the filter inlet 202 to the weir 206 a . In this embodiment, the convoluted path is in the form of a U-shaped path. If the partition 212 were not present, then water entering the sump 204 would tend to flow over the weir 206 a without passing through the sterilising filter 214 , and sterilisation would not take place.
[0030] The excess water, now sterilised, spills over the weir 206 a (arrow E) and flows down the filter outlet 208 . The water collects at the base 100 a of the collector 100 which is in communication with the piezo-electric device 102 . The piezo-electric device 102 is set to oscillate at a pre-determined frequency and magnitude such that sufficient vibrational energy is imparted to water molecules on the surface of the water in the collector 100 to overcome surface tension effects. Therefore, the water is turned into a fine mist in the interior space of the collector 100 .
[0031] The fan 104 directs an airflow downwardly into the collector 100 . This directs the fine mist towards, and down, the exhaust conduit 37 which leads to the outside of the outer case 12 . This process continues until all the water contained within the collector 100 is efficiently and hygienically removed from the collector 100 .
[0032] FIGS. 5 a and 5 b illustrate the removal of the liquid treatment module 30 from the outer case 12 for maintenance or replacement. The liquid treatment module 30 is removed downwardly from the hand dryer 10 . In this embodiment, the filter 200 forms part of the liquid treatment module 30 and is removable from the outer case 12 with the liquid treatment module 30 .
[0033] It will be understood that the invention is not to be limited to the precise details described above. Other variations and modifications will be apparent to the skilled reader.
[0034] For example, the drying apparatus need not take the form of a hand dryer. The drying apparatus could be a condenser-type laundry dryer. In such a laundry dryer, water evaporated from wet textiles in the drum (cavity) of the laundry dryer can be condensed, filtered by a filtration unit and then removed by agitation or evaporation.
[0035] Further, the invention could be utilized in other forms of drying apparatus; for example, other forms of domestic or commercial drying apparatus such as washer-dryers, ventilation-type laundry dryers or full-length body dryers.
[0036] Additionally, other forms of liquid dispersion unit can be used to disperse the collected liquid; for example, an ultrasonic generator, a fan, a heating element or electrolysing apparatus. Any of these devices could be used in place of a piezo-electric device to agitate, evaporate or electrolyse the water (or other liquid) as required.
[0037] The liquid treatment module need not be located inside a chamber present in the drying apparatus. Other arrangements are possible; for example, the module could form a part of the outer case, or could be mounted on or outside the outer case of the drying apparatus.
[0038] Further, the liquid treatment module need not be removed from the lower part of the drying apparatus. The liquid treatment module may form part of the upper side or top of the drying apparatus, and be removed sideways or upwardly depending upon the requirements of the drying apparatus. Additionally, it need not be removable and could remain fixed inside the drying apparatus.
[0039] As a further variation, other forms of airflow generator are possible. For example, an air bleed or exhaust airflow could be taken from a motor unit. For example, the motor unit for driving the drying process of the hand dryer has a fan. This fan could be used to generate an airflow to vent the evaporated water to the outside of the drying apparatus rather than using an additional fan.
[0040] Additionally, the dimensions of the glass beads need not be 4 mm. They may be varied in size from 1 mm to 6 mm. Additionally, other types of particulate filter media could be used; for example, glass-fibre brushes, plastic brushes, porous ceramics, plastic beads or small stones. What is important is that the particulate filter is formed from an inert material with a density greater than 1 g/l. The size of the particulate filter may be varied and may be any size suitable to ensure that the majority of the particulates are filtered and removed from the water to prevent the sterilising filter from clogging and becoming blocked.
[0041] As an additional variation, a number of particulate filters may be provided. They may be located outside of the sump, for example in the filter inlet to pre-filter water before it reaches the sump.
[0042] The sterilising filter need not be formed of a resin with substantially spherical particles with dimensions in the range of 0.1 to 2 mm. Other particle shapes or sizes could be used, for example by grinding. Alternatively, a single, porous block of resin could be used. Further, the sterilising filter need not be formed from a resin. Other inorganic host media could be used; for example, inorganic polymers, metal chelates, metal complexes or crystal structures.
[0043] The loading of iodine need not be 500 g/l and may be within a preferred range of 300 g/l to 600 g/l. Further, the concentration of iodine released into the water may also be outside the range of 1 to 5 ppm. What is important is that the concentration is high enough to kill the bacteria in the water whilst low enough to avoid discolouring the water. Further, the volume of the sterilising filter can be varied, provided it is sufficient to sterilise the water.
[0044] Additionally, the anti-bacterial agent in the sterilising filter need not be iodine and could include alternative bacteria-killing media; for example, a halogen-containing material or a precursor to a halogen-containing material. Typical, non-exhaustive, examples of these are materials including: Chlorine, Bromine, Iodine, Hypochlorite or Hypobromide. Alternatively, other methods of sterilising bacteria may be implemented; for example, Titanium dioxide or UV-radiation activated silver nanoparticles.
[0045] Further, the particulate filter and sterilising filter need not be located wholly in the sump. They could be located above the sump, out of the water in the sump, or partially submerged in the water in the sump.
[0046] As a further variation, the particulate-filtering media and the bacteria-killing media need not form separate stages in the filter and may be combined to form a single unit.
[0047] As a further variation, the filter need not be removable from the drying apparatus. The filter could remain inside the casing of the drying apparatus when the liquid treatment module is removed. The filter could either be removable separately from the liquid treatment module or be fixed permanently inside the casing of the drying apparatus. | A drying apparatus includes an outer case, a portion of the outer case defining a cavity in which articles can be dried, an outlet disposed at the lower end of the cavity and a filter unit arranged downstream of the outlet, wherein the filter unit includes a particulate filter and a sterilising filter. By providing this filter unit including both a particulate filter and a sterilising filter, solid matter and bacteria can be removed from the waste liquid. This results in a hygienic and sanitary waste liquid output from the filter unit. | 0 |
BACKGROUND OF THE INVENTION
This invention relates to the disposal of highly toxic chemicals such as chemicals used in chemical weapons. The Department of Defense Appropriation Act of 1986 (Public Law 99-145) has directed the Secretary of Defense to destroy the chemical weapons stockpile of highly toxic chemicals in a safe and effective manner. Further, bilateral agreements between Russia and the United States direct both countries to reduce their respective chemical weapons stockpile by year 2002.
Such chemical weapons include: 1) nerve gases such as ethyl-N, N dimethyl phosphoramino cyanidate (common name Tabun or agent GA), isopropyl methyl phosphonofluoridate (common name Sarin or agent GB), o-ethyl-S-(2 -diisopropyl aminoethyl) methyl phosphono-thiolate (agent VX), and 2) vesicants including bis(2-chloro ethyl) sulfide (mustard gas, agent H or agent HD), dichloro (2-chlorovinyl) arsine (Lewisite or agent L), bis(2(2-chloro ethylthio)ethyl)ester (agent T) or their combinations with each other or with other liquids. Nerve gases are highly toxic in both liquid and vapor form. Exposure of humans to sufficient concentrations of nerve gases leads to convulsions caused by uncontrolled stimulation of nerves, and death within minutes caused by respiratory failure. Exposure to vesicants leads to the blistering of exposed tissue, eye injuries and damage to the respiratory tracts from inhalation of the chemical. In addition to causing these immediate short term injuries, which can be fatal, some highly toxic chemicals are carcinogens.
It is clear that such toxic chemicals cannot be disposed of using traditional chemical disposal techniques because of the inherent dangers involved to human workers from the threat of contact with these chemicals. Further, they cannot be moved safely from one location to another because of the threat of an accidental release of the chemical during transport. In fact, U.S. Army studies have indicated that accidents occurring during the transportation of such highly toxic chemicals cannot be mitigated. However, existing stockpiles of such highly toxic substances cannot be left at their current storage locations indefinitely. Today, at least eight locations in mainland United States and Johnston Island in the Pacific, as well as seven or more locations in Russia contain storage sites for these highly toxic chemicals either in bulk storage containers or enclosed in weapons such as rockets, land mines, mortars or cartridges. It is estimated that there are 25,000 tons of such chemicals in the United States and 40,000 tons in Russia.
Since there currently does not exist a method of transporting such toxic substances, a need has arisen to dispose of these substances at their storage locations. However, complete disposal on site requires that a disposal plant be built at every site. Five technologies are currently being developed and may, in the future, provide the principal methods for disposal of such highly toxic chemicals. These are incineration, chemical neutralization, super critical water oxidation, steam gasification and plasma arc pyrolysis. All these methods incur tremendous costs in implementation. These costs, when multiplied by the number of plants which store these chemical weapons, become prohibitive.
Thus, a need exists for a disposal system that will enable the safe disposal of such highly toxic chemicals at reasonable cost.
SUMMARY OF THE INVENTION
The improved disposal method of the present invention involves the conversion of highly toxic chemical substances including chemical munitions to safely transportable inert products. The method includes the continuous chemical neutralization of the highly toxic chemicals and the continuous encapsulation of the neutralized products.
A preferred embodiment of the disposal method of the invention includes a neutralization process which is accomplished by mixing the highly toxic chemicals along with any wash solution used to clean out the chemical storage containers or weapons with a neutralization agent specifically chosen to neutralize the particular chemical. The mixing occurs in both a mixing head and in a twin screw extruder designed to ensure thorough mixing.
After neutralization, the neutralized chemical substance is encapsulated in a polymeric base substance via a twin screw extrusion process which is designed to separate the neutralized chemical substance into discrete, small sized particles (or droplets), and surround them with the polymeric base so that the chemical is not exposed to the surface of the encapsulated composition. The encapsulated composition is then coated with a layer of polymeric material to ensure total encapsulation, and the encapsulated neutralized chemical is injected into a sealed storage compartment that can be safely transported to a disposal site and disposed via one of the known disposal methods (e.g. incineration), or can be disposed of in a landfill. Further, mobile plants can be built according to the teachings of this invention and can be moved from one chemical weapons site to another, or from one chemical waste dumping site to another to dispose of the chemical weapon agents or toxic waste chemicals found at each site.
The main advantage of the invention is that the need for multiple disposal sites is eliminated because the neutralized and encapsulated products are capable of safe transport to a single disposal site. Accordingly, the costs are many times less expensive than any disposal system known today. The method of the invention ensures sufficient detoxification of the highly toxic chemicals at the plant at which they are being stored, to permit safe transport to the disposal site. Without the detoxification and encapsulation ability achieved with this inventive process, such transport would be impossible because of the danger to humans of transporting highly toxic chemicals. Further cost saving during disposal can be achieved by forming a mobile neutralization and encapsulation station. By using a mobile station, costs of building duplicative stations are eliminated.
BRIEF DESCRIPTION OF THE FIGURES
These and other objects, features, elements and advantages of the invention will be more readily apparent from the following description of the invention in which:
FIG. 1 is a flowchart of the overall disposal system;
FIG. 2 is a diagrammatic representation of a preferred embodiment of the disposal technology;
FIG. 3 is a diagrammatic representation of various twin screw extruder elements;
FIG. 4 is a diagrammatic representation of the cross-sectional view of the encapsulated, neutralized chemicals produced from the preferred embodiment of the invention described in FIG. 2;
FIG. 5 is a depiction of a magnified micrograph of an encapsulated, neutralized chemical substance;
FIG. 6a illustrates experimental and actual interfacial area growth at the nip region of the regular flighted screw sections of the twin screw extruder;
FIG. 6b illustrates experimental and actual interfacial growth away from the nip region of the regular flighted screw sections of the twin screw extruder; and
FIG. 7 illustrates the inter-relationships between variables and parameters used in twin screw extrusion.
FIG. 8 is a scanning electron micrograph of encapsulated simulant chemical using twin screw extrusion.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The overall method of the present invention is illustrated in the flowchart of FIG. 1. The method involves the application of chemical neutralization and encapsulation technologies to produce a readily transportable product which is safe with respect to human contact.
According to the invention, storage vessels or weapons containing highly toxic chemicals are drained of the chemicals 10 and mixed with a purge solution which has been specifically selected to chemically neutralize the particular highly toxic chemical being drained. Also neutralized at this time is a wash solution which is used to wash the storage vessels or weapons to rid them of the chemical. Next, the purge solution, chemical and wash solutions are further chemically neutralized and concomitantly encapsulated via encapsulating polymer 12. The neutralized and encapsulated solution is covered by a sleeve formation 14 of polymer which is formed around the solution and designed to ensure complete coverage of the encapsulated polymer which provides protection from the neutralized chemical. The fully encapsulated, neutralized chemical is then encased in sealed containers 16. It is now ready for safe shipping to a disposal plant such as an incinerator where it can be destroyed.
FIG. 2 illustrates a diagrammatic representation of a preferred embodiment of the apparatus involved in the inventive method. In a first stage of the apparatus, the highly toxic chemical munitions liquids are mixed in a sealed mixing head 20 with a chemical neutralizing solution of an alkaline aqueous solution selected for its neutralizing properties on the particular toxic chemical. Neutralization occurs via a hydrolysis process which results from the mixture of the chemical and the aqueous solution which alters the chemical composition of both substances and detoxifies the chemical. Examples of the process include hydrolization of GB with aqueous sodium hydroxide to remove a fluoride ion, or hydrolization of VX with aqueous sodium hydroxide so that the VX molecule experiences cleavage. Both hydrolization examples yield chemical compounds which have been detoxified. Advantageously, a caustic wash solution used to neutralize any residual toxic agents remaining in drained containers is also fed into the mixing head 20 to be detoxified. One embodiment of mixing head 20 comprises a chamber which allows for the impingement of the chemical and the aqueous solution, both comprising liquid streams. To provide sufficient mixing, the impingement velocity values of the streams should be in the regime where the Reynolds number is equal to or greater than 200-500.
The first mixing stage is followed by a second mixing stage wherein the contents of the mixing head are emptied into a second mixing head 22 which is used to incorporate polymeric thickener into the neutralized solution. The thickener is generally soluble in water and increases the viscosity of the aqueous phase so that it will be suitable for processing. One example of a thickening agent is carboxy polymethylene, which is hydrophilic and water swellable. Experiments have demonstrated that a water solution of 3% NaOH and 0.5% thickener by weight, for example Carbopol 934 available from BF Goodrich, was sufficient to result in a suitably viscous solution. The mixture of chemical munitions, neutralization agents and thickener is then injected into a continuous processor 24.
Continuous processors can comprise single screw extruders, twin screw extruders, single shaft kneaders or co-rotating disk extruders. In comparison to batch mixers which can only accommodate one "batch" at a time, continuous processors can accommodate a continuous flow. Further, in comparison to batch mixers, they have interchangeable parts, are versatile, facilitate better heat transfer and better control of product quality, and hold only a fraction of the lot of a batch mixer at any time while producing at the same production rate. Thus, a continuous processor can work a material more efficiently and with better, and more closely-tailored, results.
Any of the above-described continuous types of processor can be used in the implementation of this invention. However, the invention will be described with respect to a fully-intermeshing, co-rotating twin screw extrusion process. The twin screw extruder can provide mixing, pressurization and devolatilization in a single operation. The co-rotating twin screw extruder 24 is a continuous processor having two screws 28 which work concurrently to ensure sufficient mixing, and therefore sufficient neutralization and encapsulation to ensure safety to handlers. The screws rotate in the same direction and are self-wiping. The screws are enclosed in a tightly fitting cylindrical barrel. Thus, a small clearance exists between the barrel and rotating screw elements which prevents buildup of the materials to be mixed at the wall of the extruder. A heat transfer medium is circulated within the barrel and/or screw to maintain a constant temperature in the twin screw extruder.
The twin screw extruder is equipped with a feed port 30 for feeding the mixture comprising the highly toxic chemical, the alkaline aqueous liquid used for neutralization, the wash solution and the thickener into the twin screw extruder.
There are many methods of controlling the processing in the extruders to ensure proper chemical neutralization and encapsulation of the toxic chemical. The following provides a brief description of these methods. The screw elements of the twin screw extruder are modular and are chosen to accomplish the specific tasks required with respect to a particular chemical. Various screw elements are illustrated in FIG. 3 and include regular flighted screw sections 32 and lenticular kneading disc "paddles" 34. Also available are neutral disks and devolatilization elements. The elements are each utilized to accomplish specific processing functions, and are configured in an order particular to the required processes needed to neutralize and encapsulate a particular chemical. The configuration of the various elements is determined from an analysis of a variety of system parameters which are dependent on the particular chemical to be neutralized.
Each particular element can be oriented in a manner to accomplish the task at hand. For example, the screw elements can be oriented in a forward stagger 40 or reverse stagger 42 (see FIG. 2) depending on the results desired. When the stagger is in the reverse direction a pressure drop is created in the reverse section which requires a sufficient pressure rise in the mixture in order to continue the processing of the material in the extruder. Thus, the stagger of the elements create a means of controlling the pressurization of the mixture in the extruder. In addition to the element orientation, screw geometry is variable with respect to screw pitch size, angle and flight size. Thus, geometry selection is another method of controlling the flow of the material so that it will be properly processed.
In the following section, the operational principles of the extruder will be illustrated as well as the methodologies for proper selection of the screw configuration and the screw geometry. The results of the neutralization and encapsulation process depend on the extruder variables as well as the properties of the chemicals being processed. Also important in the chemical neutralization and encapsulation are the operating conditions of the system. The operating conditions are monitored via various sensors including temperature thermocouples, pressure transducers, and torque and rotational speed sensors located at various points along the twin screw extruder.
The extruder can include characterization equipment such as analytical characterization apparatus which can detail the particular toxic substance to be neutralized and encapsulated, and provide suggestions in the selection of screw elements, screw geometry, operating conditions and any other parameter of the system which will best accomplish the task with respect to the particular chemical at issue.
FIG. 2 depicts an embodiment of a suitable screw geometry for accomplishing chemical neutralization and encapsulation which generally comprises three zones: 1) the neutralization zone 44, 2) the modification zone 48, and 3) the encapsulation zone 52. The neutralization zone 44 provides a sealed region whereas the channel is completely full at both ends, in which the hydrolysis reaction achieves sufficiently high conversions (i.e., conversion from toxic chemical to detoxified chemical) of the chemical munitions to ensure a high degree of chemical neutralization. The mean residence time in the neutralization zone necessary to achieve a sufficiently high conversion of the chemical munition liquid depends on the pH and temperature of the reaction. For example, based on the published first order rate constant for the hydrolysis reaction of GB with caustic at 25° C. having a pH of 10 without any catalyst, the estimated residence time for 90% conversion is 40 minutes. [Gustafson and Martell, J. Am. Chem. Soc., 82:2309 (1962)]. The weight ratios of GB to caustic (1N solution) used was 1 to 10. This is higher than the stoichiometric ratio of 1 to 7 and assures an alkaline environment throughout the reaction. It is possible to decrease this residence time by a factor of one half for each 10° C. increase in temperature. Thus, only a residence time of 5 minutes is necessary at 55° C. to achieve 90% conversion. Various catalysts can be incorporated to increase the neutralization rate even further thus decreasing the residence times.
The residence time of the chemical in the neutralization zone is controlled by varying the screw geometry. For example, in FIG. 2, the reverse staggered screw elements are included at the beginning and end of the neutralization zone to provide a pressure decrease in the flow which results in a longer residence in the zone. Further, these fully-flighted reverse screw sections are provided to form melt seals around the zone so as to enclose the chemical within the zone and ensure a greater degree of neutralization. However, the neutralization process continues throughout the length of the extruder during the modification and encapsulation zones.
An example of the screw configuration and orientation of the neutralization zone is depicted in FIG. 2. The zone begins with a fully flighted reverse staggered screw element 42 to provide sealing of the extruder from the outside. Sealing is provided by the reverse drag created in the flow by the reverse stagger element 42. This element comprises a helix angle of -5.9° with respect to the vertical axis. The diameter of the screw root is 27 mm and the pitch (i.e. axial distance between flights) of the flighted section is 12.7 mm. The channel depth of the screw is 11.9 mm and the flight width at the tip of the screw is 2.9 mm. The element comprises two screw turns. Screw elements such as kneading disks can be incorporated into the neutralization zone to generate better mixing.
The reverse stagger element 42 is followed by a forward flighted element 43 having a helix angle of 5.9° with respect to the vertical axis. The diameter of the screw root is 27 mm, the pitch is 12.7 mm, and the channel depth is 11.9 mm. The flight width at the tip of the screw is 2.3 mm. The element comprises 4 screw turns. Following elements 43, three double channel forward stagger elements 40 provide mixing and pressurization. The pitch of each element is 25.4 mm (i.e., one inch) and the channel depth is 11.5 mm. The screw root diameter is 27.9 mm, the helix angle is 22.4° from the vertical, and the flight width is 1.5 mm at the tip of the screw. Each element comprises one screw turn. Following the three forward stagger elements 40, another reverse stagger element 46 is included to create a similar seal to the reverse element 42 prior to the modification zone. The specifications of the reverse stagger element are identical to those of element 42. Thus, the mixture is maintained in the neutralization zone via the screw element geometry for the time necessary to neutralize the highly toxic chemical.
In the modification zone 48, a polymeric matrix, e.g., thermoset for relatively low temperatures, thermoplastic for higher temperatures, and various modifiers including curing agents and catalysts for thermosetting polymers, are injected into the extruder and mixed with the neutralization products emerging from the neutralization zone. The screw configuration and orientation of the modification zone generally includes only three forward stagger elements 50 for conveying and premixing the neutralization products with the polymeric matrix. The forward elements 50 have a helix angle of 5.9° with respect to the vertical axis. The diameter of the screw root is 27 mm, the pitch is 12.7 mm, and the channel depth is 11.9 mm. The flight width at the tip of the screw is 2.9 mm. Each element comprises 2 turns. These elements 50 are followed by a set of ball wing type screw elements 51, at which the encapsulating polymer and other additives are fed into the extruder through a second feed port. The ball wings are included to scrape the surface of the extruder barrel to eliminate stagnant regions.
The encapsulation zone 52, encapsulates the neutralization products in the polymeric matrix by controlling the configuration and operating conditions of the extruder. The encapsulation zone 52 continues to mix and pressurize the detoxified mixture and the polymeric matrix until the detoxified mixture is reduced to small droplets which are embedded in the polymeric matrix. The orientation and configuration of elements in this zone include the following specifications. One forward stagger element 53 having the same configuration as elements 50 and two forward stagger elements 54 having the same configuration and orientation of the element 43 in the neutralization zone are positioned at the beginning of the encapsulation zone. They continue the mixing process of the detoxified mixture and the polymer matrix and pressurize the melt. The forward stagger elements are followed by a two inch long kneading disc block 55 configured to be staggered at a 60° reverse angle. The kneading discs are used to create better dispersive mixing and to improve the distributive mixing capability, the merits of which will be discussed below. This is followed by two reverse stagger elements 56 which pressurize the preceding portions to ensure proper mixing of the detoxified mixture and the polymer matrix and provide a melt seal to the encapsulation zone. The reverse stagger element configuration is identical to those discussed with respect to elements 42 and 46 (above). The reverse stagger elements are followed by two forward stagger elements 58 with a total length of 6". These elements both pressurize the mixture and accomplish the final mixing which encapsulates the small particles of the detoxified mixture in the polymer matrix. Further they allow sufficient pressurization of the encapsulated solution to be shaped into a strand at a die 62. The forward elements 58 have a helix angle of 22.4° with respect to the vertical axis. The diameter of the screw root is 27.9 mm, the pitch is 25.4 mm and the channel depth is 11.5 mm. The flight width at the tip of the screw is 1.5 mm. Each element comprises 1.5 turns. The combination and order of the screw elements results in separating the neutralized chemical into small droplets. Other variables such as screw rotational speed, volumetric flow rate and temperature are selected to sufficiently process the mixture as well. Specifically, these parameters are selected so that encapsulation will occur without premature curing of the thermosetting matrix.
The die 62 geometry is important and must be of a length to allow for sufficient curing and shaping of the thermosetting polymer within the die and to ensure encapsulation as well as cooling and solidification of the polymer outside the die. Additionally, the die entry geometry is an important part of the twin screw extrusion technology. It is designed with care primarily to allow for the smooth transition of the material from the exit of the twin screw extrusion section into the die. The die entry should be designed to eliminate dead spots, i.e., stagnant regions where the melt could circulate indefinitely.
The extruder sections also must be designed to provide a flowable matrix to the die. For example, for thermosetting matrices, an extruder geometry which results in an improper increase of the residence time in the modification and encapsulation zone may lead to premature curing and gelation of the thermosetting matrix thus leading to stagnation at various locations at the die entry.
Stress distribution must be maintained within acceptable limits and is dependent on the amount of separation between the tips of the screws and the walls of the approach region into the die. Especially for viscoplastic materials, the stress magnitudes at every location in the entry to the die geometry should be controlled by selecting the distance of separation between the conical tips of the screws and the die.
The die is interfaced to a second extruder 64, which generally comprises a single screw extruder of a type well known in the art. This extruder provides a pressurized polymeric melt to coat the outer surface of the encapsulated mixture as it emerges from the twin-screw extruder (the emerging mixture is commonly referred to as a "strand"). This process is, thus, a co-extrusion process. Additional extruders depositing additional layers onto the strand can be included as well. For example, an adhesive layer can be deposited between the outer polymeric sleeve and the strand to ensure that the polymeric sleeve remains in place.
Once all layers have been deposited on the strand, the ends of the resultant strand are capped with the second extruder and cut. This involves halting the feeding of the chemical and neutralization agents from the twin screw extruder to allow for polymer from the single screw extruder to fill end sections of the strand thus forming seals. The encapsulated strand is then cooled outside the die and fed into sealed container 66 which can be removed safely from the disposal site. Upon the completion of a run, the extruder is purged entirely by running only the polymeric matrix for a sufficient duration of time to eliminate traces of the previous mixture. Any volatiles which are generated by the process are recycled back to mixing heads 20, 22, after being cooled in condenser 68 thus providing an additional safety feature to ensure a safe product.
FIG. 4 illustrates a cross section of a co-extruded and encapsulated strand. This strand comprises a neutralized chemical 80 that has been broken down into small droplets which are encapsulated in polymer 82. The droplets of chemical and polymer are then coated with additional polymer 84 to ensure that the encapsulation is complete. The ends 86 are capped with polymer as described above. As is evident, the neutralized and encapsulated chemical is completely isolated and safe for transport to a disposal plant. FIG. 5 illustrates a magnified micrograph which demonstrates the desired morphological distribution of the neutralization products 90 in the encapsulating polymer 92.
Although the toxic chemical is not neutralized one hundred percent in accordance with this process, there is little fear of toxic chemical diffusion through the polymeric encapsulation layer. Because the neutralization rate is faster than the diffusion rate, all the remaining toxic chemical will be neutralized before it has an opportunity to diffuse through the polymeric barrier sleeve. For example, with respect to the hydrolysis reaction described above from Gustafson and Martell, 10% of the GB remains in toxic form after a neutralization time of 5 minutes at 55° C. Assuming that the rate of neutralization in the more viscous stagnant encapsulating region is an order of magnitude lower than in the neutralization section at the entrance, it would take approximately thirteen hours for 99% of the remaining 10% GB to hydrolyze. On the other hand, based on a typical permeability coefficient of chlorinated materials in polyethylene or polystyrene, the permeation time through a 9 mm polystyrene barrier layer is in the order of years. Thus, diffusion presents no threat of harming those in contact with the neutralized, encapsulated products.
However, there is a threat of toxic leakage through the encapsulation layer if the neutralization and encapsulation processes are not performed correctly. The transport and mixing in an extruder is essential, and, when complete, ensures sufficient neutralization and encapsulation. The following is a description of how the workings of a twin screw extruder neutralizes and encapsulates these highly toxic chemicals. Fully flighted screw sections of the twin screw extruders are efficient in accomplishing the necessary transportation and pressurization in the forward mode, but their transport capability depends on their geometry. Generally, small helix angles and shallow channels give rise to greater conveying and pressurization capabilities in the forward mode.
When fully flighted screw sections are incorporated in the reverse direction they provide effective melt seals which capture the contents to be mixed in one area of the extruder until the pressure from the melt seal is overcome. Thus, effective mixing takes place in these "sealed" regions. In this situation, the drag direction opposes the direction of flow which generates a pressure drop over the reversely configured screw section. To overcome this pressure drop and maintain transport, the screw elements preceding this section need to provide sufficient pressurization. Thus, forward flighted sections should precede the reversely configured screw sections. Further, the total helical length of the forward section should be greater than the total helical length of the reversely configured section which follows it. The loss of pressure over the reversely configured screw sections also necessitates that the extruder be completely full at that section. Degree of fill analysis will be discussed below.
Distributive mixing is necessary for encapsulation and occurs when the various components of the solution and the polymer are moved with respect to one another so that the resultant positions of these components are different from what they were relative to one another prior to any mixing. The elements of the various components are interspersed with one another so as to form a homogenous composition of different ingredients. In the present case, distributive mixing occurs when the chemical solution and the polymer used for encapsulation are moved relative to one another so as to encapsulate the solution in the polymer.
To achieve the desired mixing, an interface orientation is introduced to the polymer and the chemical solution as they flow from one screw to the other at the nip region, i.e., where the two screws intermesh. The interface orientation occurs on the basis of the reorganization of the geometrical area of interface between the polymer and chemical solution. Such interface changes as the two ingredients become mixed. For fully-flighted screw sections, high strain values can be introduced into the materials during the entire length of the flights, and the further reorientation of the interface occurs largely at the nip region. This results in substantial encapsulation of the neutralized chemical before reaching the end of the extruder.
FIG. 6 illustrates the distributive mixing capability of the extruder. The encapsulation of a colored tracer fluid 70 in another fluid 72 is illustrated both experimentally and theoretically. The tracer fluid is initially placed at two different configurations to illustrate the encapsulation mechanisms associated with the system: FIG. 6a illustrates distributive mixing at the nip region, and FIG. 6b illustrates distributive mixing away from the nip region in the fully-flighted conveying and pressurization elements of the twin screw extruder. At the nip region, the growth of the reorientation occurs as a function of the relative velocity of the nip region and the width of the screw flights. A greater screw flight width results in a greater change in the fluid's path and a greater reorientation of the interfacial area between the components at the nip region. This reorientation results in better encapsulation of the detoxified chemical. Thus, by altering the screw flight width, the extent of distributive mixing at the nip can be controlled. Distributive mixing can also occur at a region along the extruder away from the nip region. For this scenario, tracer fluid 74 is positioned in one half of the channel width of a flight at an area removed from the nip region. As the extruder is operated, the fluid interface redistributes over the entire channel width resulting in encapsulation.
Dispersive mixing, which is necessary to introduce changes in the physical properties of the components of the mixture, requires a high shear stress to be applied to the mixture by passing the mixture repeatedly through small gaps at high velocities. As stated above, the dispersive mixing ability of the fully flighted screw sections is very small. Thus, to achieve dispersive mixing in the instant system, kneading discs 34 (see FIG. 3) are used. Kneading discs create large shear stresses at the interface between the sets of kneading discs by squeezing the solution and polymer mixture through the small gap between the kneading discs. This motion creates excellent dispersive mixing.
Depending on the stagger angle of the kneading discs, neutral, forward or reverse screw sections can be used to generate different stress, temperature and velocity profiles. By calendering the mixture (i.e., squeezing and pressurizing locally) at the intermesh between the two kneading discs and between the kneading discs and barrel of the extruder, axial velocities are created which can be negative or positive, depending on the direction of least resistance. This controlled back and forth motion also gives rise to flow and deformation in the kneading discs section which results in additional flow stress generating additional dispersive mixing which is very effective in rupturing large liquid drops to form small droplets.
In addition to mixing, another requirement for proper encapsulation is a proper degree of fill in the extruder cavity. Degree of fill is defined as the ratio of the volume of the solution in the extruder divided by the total volume available in the extruder, both determined over a constant axial length. The degree of fill varies with the stagger angle of the screw flights. Generally, the degree of fill and the distance over which the fully-flighted screw channel and kneading discs remain full are greater with stagger angles having negative orientations. With such reverse stagger angles there is pressure loss over the entire section. This necessitates that the entire section, and a portion of any preceding section, be completely full. This is suggested by experimental results wherein a fully flighted screw section preceding a series of kneading discs of a 30° reverse stagger angle has a higher degree of fill than that preceding a 60° reverse stagger angle section or a 90° neutral stagger angle section. Similarly, the degree of fill at a 60° forward stagger angle section is greater than that found in a 30° forward stagger section.
Finally, the third important consideration for this system (after geometry and configuration) is operating conditions. System operating conditions are selected to process at an optimum rate with respect to throughput and safety and to accommodate a particular toxic chemical so as to optimize the neutralization and encapsulation of that chemical. The primary operating conditions include mass flow rate, screw speed, and temperature of the die, barrel and screw sections. These parameters will affect the extent of mixing by controlling the residence time and distribution of the material, and the strain, stress and temperature distributions imposed on the mixture in the extruder. Under improper conditions, degradation and premature curing may occur. The amount of air incorporated into the suspension and the amount of solvents remaining in the suspension at the exit from the die will also be affected by the selection of operating conditions. The overall relationships between the different system variables and operating condition parameters are shown in FIG. 7.
The above-described disposal technology is safe due to the continuous nature of the operation. Only a small quantity of highly toxic chemical is found in the twin screw extruder at any given time. Other advantages include excellent heat transfer from the high surface to volume ratio in the extruder. The self-wiping action of the twin screw extruder elements provide self-cleaning to avoid formation of stagnant regions. The twin screw extrusion machine is equipped with computerized process control and remote operation and it does not require any manual handling. Thus, the workers are not exposed to the highly toxic chemicals. The barrel of the twin screw extruder has a splitable "clam shell" design with hydraulic actuators to allow for quick release and instantaneous flooding of the contents of the extruder with aqueous alkaline solution.
The process area is continuously monitored for possible contamination with sensors such as broad based solid state sensors. In the event of detection of any chemical warfare agent, the process will automatically shut down. In the neutralizationen-capsulation process, samples are to be withdrawn towards the end of the neutralization zone. At this location, there will be a flange, probe and solenoid valve assembly with the valve activated remotely. The extent of neutralization can be monitored by determining the total quantity of halogen ions formed during the hydrolization process of GB. Alternatively, in the neutralization of VX, the extent of reaction can be monitored by determining the pH of the sample (pH decreases as hydrolysis proceeds) and comparing it to the estimated pH of the feed. A more accurate (but also more expensive) approach for monitoring the progress of the reaction is to analyze the parent molecule, i.e., GB, HD or VX through the liquid chromatography/mass spectrometry (LC/MS) technique. LC/MS is used as a technique for the identification and quantification of the highly toxic chemical and its products after hydrolysis. Thus, LC/MS can be used to determine both the required system for neutralization and encapsulation of the highly toxic chemical and the stage of the hydrolysis reaction (i.e., determining whether the chemical has been neutralized). The output can be compared with predetermined values to be used as feedback for computerized process control.
Further, the disposal technology is mobile so that the plant can be taken from site to site thereby greatly decreasing costs as only one of these processing stations need be built.
While it is apparent that the invention herein disclosed fulfills the objects above stated, it is recognized that numerous embodiments and modifications may be devised by those skilled in the art and it is intended that the appended claims cover all such modifications and embodiments as fall within the true spirit and scope of the present invention. Other types of processors may be used to concomitantly neutralize and encapsulate the neutralization products. Other continuous processors include continuous kneaders, counter-rotating twin screw extruders, and single screw extruders. Batch processors can also be used, but are less efficient. The preferred embodiment assumes that the toxic chemicals will be in containers or in weapons, which can be disassembled so that the toxic chemical can be removed therefrom. In the event that the weapons cannot be disassembled, they can be cryogenically broken into small pellets, which can be fed together with the toxic chemicals into the continuous processor for concomitant neutralization and encapsulation.
The disposal method of this invention applies equally to any chemical or other hazardous solution which cannot be handled by humans in its present state. These include but are not limited to chemically contaminated soil and groundwater, industrial chemicals or chemical waste, such as halogenated organic chemicals other than chemical warfare agents, found in major dump sites such as the Superfund locations. With minor modifications to the feeding mechanisms, processing configuration and geometry, encapsulation materials and operating conditions, these chemicals can be disposed of using the neutralization and encapsulation method of the invention.
The process can be automated by equipping it with robotics-based sample collection systems which would collect samples from individual storage containers and analyze them for precise chemical content. The composition of the sample can also be determined with LC/MS analysis. The analysis of the chemical nature of the sample can then be carried out (with or without human intervention) to determine the chemical treatment necessary to neutralize the chemical targeted for treatment. Upon the findings of this analysis, a computerized menu can select the proper neutralization agent, the optimal encapsulating polymers, the configuration and geometry of the various extruder elements, the necessary quantities of elements of the process and the proper operating conditions for the neutralization and encapsulation of the particular chemical. Various sections of the extruder can be modified by employing remotely activated adjustable screw elements. The sampling system can also be installed directly in the feed line leading to the extruder.
EXAMPLE
The following example describes the result of a series of neutralization and encapsulation experiments performed on the twin-screw extruder apparatus described in detail above. The experiments concerned neutralizing a simulant with NaOH, and encapsulating the simulant with a twin screw extruder in a thermosetting polymer.
Specifically, the simulant comprised an aqueous solution of 200 ppm (w/w) trichloroethylene. Neutralization was performed by mixing 2 ml batches of 10N NaOH solution with 700 ml of simulant in a well stirred vessel at 100° C. for two hours. This resulted in 95% neutralization. The neutralization products were mixed with 0.5% by weight crosslinked acrylic acid polymer to form a hydrogel. To achieve encapsulation, the hydrogel was fed into the twin screw extruder at a constant mass flow rate of 5.6 lb per hour. An epoxy polymer of a diglycidyl ether of bisphenol-A was used as the encapsulating polymer and was fed into the extruder at 8.4 lb. per hour. A curing agent of precatalyzed trifunctional mercaptan based hardener with tertiary amine was also fed into the extruder at 8.4 lb per hour. The extruder was maintained at 57° F. with a screw speed of 30 rpm.
Upon completion of the screw operations the formulation was well mixed, as is evident from FIG. 8 which is a reproduction of a photograph 80 of the extruder products of the above-described example taken by a scanning electron microscope and magnified 2,000 times. The hydrogel 82 was thoroughly and uniformly mixed with the epoxy polymer 84 and finely dispersed in the polymer. Specifically, the mean diameter of the hydrogel deposits was approximately 2.4 micrometers and the mean distance of epoxy polymer between hydrogel deposits was approximately 4.4 micrometers. Thus, hydrogel deposits were well encapsulated in the epoxy polymer. With the use of a second extruder to cover the formulation with a 1-5 mm coating of encapsulating polymer (as described above), the formulation would be sufficiently encapsulated so that it would be safe for transport. | An apparatus and method for disposing of highly toxic chemicals including the steps of chemical neutralization of the highly toxic chemical so as to substantially detoxify the chemical and encapsulation of the neutralized highly toxic chemical in a material which shields the neutralized highly toxic chemical from contact with anything outside of the encapsulation substance. | 0 |
BACKGROUND OF THE INVENTION
[0001] 1. Statement of the Technical Field
[0002] The present invention relates to applications level security and more particularly to password processing in a computing application.
[0003] 2. Description of the Related Art
[0004] Applications level security has been of paramount concern for applications administrators for decades. While access to an application, its features and data can be of no consequence for the most simple of computing tools such as a word processor or spreadsheet, for many applications, access must be restricted. For example, in financial applications and other such applications processing sensitive data, as well as in computing administration type applications, protecting both confidentiality and access to important and powerful computing functions can be so important so as to require access control.
[0005] Generally, applications level security incorporates authentication logic for retrieving or otherwise obtaining unique data such as a pass-phrase, key, PIN, code, biometric data, or other such personally identifying information (collectively referred to as a “password”). Once retrieved, the password along with a user identifier can be compared to a known password for the user. If the comparison can be performed favorably, the password can be validated and access can be granted to the user as requested. In contrast, if the comparison cannot be performed favorably, access to the user can be denied. Moreover, protective measures such as invalid attempt logging can be activated.
[0006] Conventional password processing involves the one-way hashing of the known password and the storage of the hash in a data structure. When a user provides a password as part of an attempt to access an application, an application function, or application data, the password can be compared to the hash through a call to logic managing the data structure to determine whether access ought to be granted. Though the encrypted content of the hash can remain safely hidden from prying eyes, one able to access the hash can randomly compare a large number of possible passwords against the hash in what is known as a “dictionary attack”.
[0007] To circumvent the possibility of a dictionary attack, several password authentication techniques have been proposed. For instance, some have attempted to secure the password hash itself through a common technique known as “salting”. Salting ultimately results in dictionary attacks becoming substantially more time and computing intensive. Salting, however, does not secure a single password against brute force guessing. Other techniques include introducing real time delays within the authentication logic in reporting failed attempts. Alternatively, the requestor can be locked out of the authentication logic after a pre-determined number of failed password guessing attempts.
[0008] Finally, some have suggested replacing local authentication logic with a remote procedure call to a trusted server providing the password. In this way, the hash can become inaccessible to an attacker as the actual authentication can be performed remotely based upon a communicated request. Of course, to implement the latter would require all authentication logic within the application itself to be located and rewritten. Accordingly, implementing a remote authentication procedure can disrupt the structure of existing applications and can result in the undesirable breaking of the source code of the application.
SUMMARY OF THE INVENTION
[0009] The present invention addresses the deficiencies of the art in respect to access control and provides a novel and non-obvious method, system and apparatus for user authentication and password validation. In a password validation method, a user authentication request can be received which can include at least a password and a user identifier for the password. Subsequently, authentication data can be retrieved for the user identifier. In this regard, a hash value for a password corresponding to the user identifier can be retrieved. Notably, responsive to detecting an extended password string in the authentication data, password validation can be outsourced to a remote authentication process. Otherwise the password validation can be processed locally. Consequently, as the extended password string contains an encrypted value, the password string will have been rendered impervious to password guessing or dictionary attack. Yet, in accordance with the preset invention, an existing interface to the password validation logic can be maintained for the benefit of existing applications utilizing the validation logic.
[0010] In a preferred aspect of the invention, the detecting step can include detecting an extension header in the authentication data. For instance, the detecting step can include detecting a character in the extension header not available for use in a hash of a password. Consequently, the outsourcing step can include forwarding at least the password and an encrypted form of a hash value extracted from the extended password string to the remote authentication process. In particular, the outsourcing step can include executing a remote procedure call to the remote authentication process. In any case, the forwarding step additionally can include forwarding at least one of a hash type, a canonical user name, and an expiration indicator along with the encrypted form of the hash value.
[0011] A system for secure password validation can include a local authentication process configured for coupling both to local authentication data and to a remote authentication process. The system also can include a comparator disposed in the local authentication process and programmed to detect an extended password string in the local authentication data. Finally, the system can include a remote authentication handler disposed in the local authentication process and programmed to outsource password validation to the remote authentication process responsive to the comparator detecting an extended password string retrieved for a supplied user identifier. Preferably, the remote authentication handler can be a remote procedure call to the remote authentication process.
[0012] Additional aspects of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The aspects of the invention will be realized and attained by means of the elements and combinations particularly pointed out in the appended claims. 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.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The accompanying drawings, which are incorporated in and constitute part of this specification, illustrate embodiments of the invention and together with the description, serve to explain the principles of the invention. The embodiments illustrated herein are presently preferred, it being understood, however, that the invention is not limited to the precise arrangements and instrumentalities shown, wherein:
[0014] FIG. 1 is a schematic illustration of a password verification system which has been configured in accordance with a preferred aspect of the inventive arrangements;
[0015] FIG. 2 is a pictorial illustration the composition of exemplary password extension strings configured for use in the system of FIG. 1 ; and,
[0016] FIGS. 3A and 3B , taken together, are a flow chart illustrating a process for validating a password in the system of FIG. 1 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0017] The present invention is a method, system and apparatus for remotely validating a password. In accordance with the present invention, an extended password string can be formed to include a header indicating the presence of an extended password string along with a network address for a validation process and an encrypted form of a password. Moreover, the hash value or password can be encrypted using a key such that only the validation process can decrypt the hash value. In this regard, the key can be a public portion of a public-private key pairing associated with the validation process. In any case, the extended password string subsequently can be stored in association with a specific user identity.
[0018] When a user claiming the specific user identity provides a password for validation, the extended password string can be retrieved and the encrypted form of the password can be forwarded to the validation process along with the claimed user identity and the provided password. In particular, the password, claimed user identity and the extended password string can be provided to the validation processor by way of a remote procedure call. In any event, the validation processor can decrypt the password and, where the decrypted form of the password is a hash value, the hashing function known to the validation processor can be applied to the provided password. The decrypted hash value and hash value produced for the provided password can be compared and the result can be provided to the calling process.
[0019] In further illustration, FIG. 1 schematically depicts a password verification system which has been configured in accordance with a preferred aspect of the inventive arrangements. The system can include a local authentication server 110 configured for use by an application 140 . The local authentication server 110 further can be coupled to a remote authentication server 120 over a computer communications network 130 . The local authentication server 110 can host a local authentication process 160 , while the remote authentication server 120 can host a remote authentication process 170 .
[0020] The local authentication process 160 can be communicatively linked to local authentication data 150 A, for instance where the local authentication data 150 A is stored in the local authentication server 110 . Similarly, the remote authentication process 170 can be communicatively linked to remote authentication data 150 B, for instance where the remote authentication data 150 B is stored in the remote authentication server 120 . Importantly, the local authentication process 160 can include a local handler 160 C programmed to authenticate a user ID/password combination 190 provided through the application 140 based upon the provided password, a known hash function and a pre-stored hash value for a password associated with the user ID as stored in the local authentication data 150 A.
[0021] Unlike conventional password validation technologies, the system of the invention also can include a remote handler 160 B and a comparator 160 A. Specifically, when processing a provided user ID/password combination 190 , it can be determined in the comparator 160 A whether data retrieved for the user ID from the local authentication data 150 A includes an extended password string 180 . If so, the remote handler 160 B can pass the extended password string 180 along with the password and user ID extracted from the combination 190 to the remote authentication process 170 for remote password validation. Otherwise, the validation of the user ID and password can be performed by the local authentication process 160 .
[0022] The extended password string 180 advantageously can be configured so as to be storable in the local authentication data 150 A as would be the case with password information not packaged as an extended password string. For instance, where the extended password string 180 is stored in a field in a database, the format of the extended password string 180 can be such that the storage of the extended password string 180 in the field of the database can be accommodated without modifying logic arranged to access and retrieve data from the field in the database. As an example, FIG. 2 is a pictorial illustration the composition of exemplary password extension strings configured for use in the system of FIG. 1 .
[0023] Referring to FIG. 2 , an extended password string 200 can include an extension header 210 , a password domain 220 and a hash value of a password 230 which has been encrypted according to encryption key 240 . Specifically, the extension string 200 can include data which can be distinguished from an encoded password sufficient to indicate the presence of an extended password string. For example, where the password data ordinarily stored in a local authentication data structure is Base64 encoded data utilizing hexadecimal values, the extension header 210 can include non-hexadecimal data, such as the letter “G” so as to indicate the presence of the extended password string.
[0024] The password domain 220 can be mapped to a network address for a remote server or remote process address space hosting the remote authentication process of the present invention. Utilizing the password domain 220 , a local authentication process can properly transmit the user ID, password and extended password string to the remote authentication process for validation. Finally, the hash value of the password 230 can be a hash computed value which further has been encrypted using a key 240 such as the public key associated with the remote authentication process.
[0025] In an alternative aspect of the invention, the extended password string 200 can include a key identifier 250 suitable for indicating to the remote authentication process which key to utilize in decrypting the encrypted portion of the extended password string 200 . Moreover, in the alternative aspect of the invention, the hash value 260 can include a hash of the password 230 (or possibly multiple hash values) along with an indication of the hash type 270 such as “legacy”, “digest-md5”, “cram-md5” and the like, a canonical user name 280 which can be used for monitoring and logging password attempts on a per use basis, and an expiration date or time 290 beyond which the password is considered no longer valid. Once again, the hash 260 can be encrypted using the key 240 such as the public key associated with the remote authentication process.
[0026] In accordance with the present invention, the local authentication process can discriminately outsource password validation to a remote authentication process based upon the presence of an extended password string for a specified user. In this regard, FIGS. 3A and 3B , taken together, are a flow chart illustrating a process for validating a password in the system of FIG. 1 . First considering FIG. 3A , beginning in block 310 , a request for authentication can be received in the form of a password validation request. In block 320 , authentication data associated with a user ID provided with the authentication request can be retrieved and inspected to determine in decision block 330 if the retrieved authentication data is an extended password string. If in decision block 330 it is determined that the retrieved authentication data is not an extended password string, in block 340 the password can be processed normally, for example by comparing a hash of the provided password with a hash value stored in the retrieved authentication data.
[0027] If in decision block 330 it is determined that an extended password string is present in the retrieved authentication data, in block 350 the password domain can be extracted or otherwise read from the extended password string and in block 360 , the process of validating the received password can be deferred to the remote authentication process. Turning now to FIG. 3B , in block 370 in the remote authentication process the extended password string can be decoded and in block 380 the hash value for the password can be decrypted using a key known to the authentication process. Finally, in block 390 , the password can be validated against the decrypted hash value. Notably, in an alternative embodiment, a hash value stored for the user in association with the remote authentication process can be retrieved by the remote authentication process and validated against a hash of the supplied password.
[0028] Optionally, one or more post-processing functions can be applied subsequent to the password validation process in block 400 . Such post-processing functions can include logging log-in attempts and the application of password policies such as lock out on a certain number of failed attempts. Finally, in block 410 the validation can be reported to the local authentication process which in turn can report the result of the authentication request to the requesting process or application.
[0029] Several advantages to the present arrangement will be recognized by the skilled artisan. First, given the backwards-compatible structure of the extended password string, the interface to the local authentication process need not be changed as the structure of the extended password string will not break a method processing the extended password string unknowingly. Second, by encrypting the has using a key known only to the remote authentication process, even brute-force methods cannot successfully resolve a multiplicity of provided passwords against the encrypted and thereby protected hash. Most, importantly, only the logic of the local authentication process need be changed while all other application logic accessing the local authentication process can remain unaware of the possible outsourcing of password validation duties.
[0030] The present invention can be realized in hardware, software, or a combination of hardware and software. An implementation of the method and system of the present invention can be realized in a centralized fashion in one computer system, or in a distributed fashion where different elements are spread across several interconnected computer systems. Any kind of computer system, or other apparatus adapted for carrying out the methods described herein, is suited to perform the functions described herein.
[0031] A typical combination of hardware and software could be a general purpose computer system with a computer program that, when being loaded and executed, controls the computer system such that it carries out the methods described herein. The present invention can also be embedded in a computer program product, which comprises all the features enabling the implementation of the methods described herein, and which, when loaded in a computer system is able to carry out these methods.
[0032] Computer program or application in the present context means any expression, in any language, code or notation, of a set of instructions intended to cause a system having an information processing capability to perform a particular function either directly or after either or both of the following a) conversion to another language, code or notation; b) reproduction in a different material form. Significantly, this invention can be embodied in other specific forms without departing from the spirit or essential attributes thereof, and accordingly, reference should be had to the following claims, rather than to the foregoing specification, as indicating the scope of the invention. | A method, system and apparatus for secure password validation can include a local authentication process configured for coupling both to local authentication data and to a remote authentication process. The system also can include a comparator disposed in the local authentication process and programmed to detect an extended password string in the local authentication data. Finally, the system can include a remote authentication handler disposed in the local authentication process and programmed to outsource password validation to the remote authentication process responsive to the comparator detecting an extended password string retrieved for a supplied user identifier. Preferably, the remote authentication handler can be a remote procedure call to the remote authentication process. | 6 |
BACKGROUND OF THE INVENTION
Labels for bearing various marketing information or other indicia are customarily supplied on a backing strip or tape with the adhesive side of the labels being in contact with the tape and detachable therefrom. When separated from the backing tape the labels must be transported and/or retained with the adhesive side out for application to the desired article or package. The retaining means must be capable of releasing the label at a predetermined time or position. A typical apparatus for carrying out these functions is shown and described in U.S. Pat. No. 3,885,705 wherein a perforated grid for receiving such a label has a plurality of openings through which a vacuum may be "drawn" (or more effective) so as to retain the label. Other openings in this grid are connected to air "blast" tubes so that at the appropriate time relatively high velocity air may be blown there-through to blow the label from the grid into the article. It will be appreciated that in supplying successive labels to successive articles each succeeding article must await the placement of its intended label onto the grid and then moved into position over the grid and label for application of the label to the article. A somwhat similar grid arrangement is also shown and described in U.S. Pat. No. 3,645,832 but with a different arrangement for supplying the label-ejecting air blast thereto. In U.S. Pat. No. 3,655,492 a label-printing and applicating system is shown wherein the labels are held onto a sponge-faced bridge or head by means of vacuum operative through openings in the fixed position bridge and sponge member. The sponge member, being resilient, is able to deform sufficiently to assume a shape conforming to the shape of the package when pressed there against.
It will be appreciated that in all these prior art arrangements the label is transferred to and held by a fixed position head or bridge, the package is then moved into position adjacent to or in contact with the label-retaining head and thereafter the label is applied to the package which must be then removed before this sequence can be recommenced for the next package. Because of this sequential operation such systems are inherently limited in the speed at which labels may be applied to packages by the time required to perform each sequential step.
SUMMARY OF THE INVENTION
The present invention provides improved label applying means which permits packages or articles to be moved rapidly along a conveyor system and receive the proper labels therefore. The labels are retained on the label applicator of the invention by maintaining less than atmospheric air pressure on one side of the label and then applied to the intended article by providing a greater than atmospheric pressure on the aforesaid side to "blow" it onto the article so that the adhesive side of the label contacts and adheres to the package.
With the present invention the applicator rotates from one position where it receives and retains the label, adhesive side out, to a second position at which the label is blown off the applicator into contact with the article. The applicator head of the invention is provided with diametrically opposed perforated portions each of which portions are capable of retaining the label in a first position and then ejecting the label therefrom when the applicator head is rotated to a second position. Hence a label may be delivered to the applicator head for retention thereby while the preceding label is being applied to the article.
The rotatable applicator head of the invention is internally provided with less than atmospheric pressure on the inside of one of the perforated portions in the label-receiving position and to greater than atmospheric pressure again on the inside of this same perforated portion upon rotation of the head to the label applying position. The air pressure, either lesser or greater than atmospheric, is established through the perforations in the head so as to be operative on the label surface on the outside of the perforated portions.
In the label-receiving position of the applicator head the first perforated portion communicates by an internal channel to a source of sub-atmospheric air pressure. When the applicator head is rotated, this perforated portion is brought into communication by a second internal channel with a source of super-atmospheric air pressure. The second perforated portion of the head is likewise alternately brought into communication with the aforementioned differential air sources upon rotation of the head. Rotation of the applicator head is caused by drive means which is actuated in response to the movement of an article or package to or past a predetermined point on the conveyor system.
Thus, as rapidly as packages move along the conveyor system respective labels intended therefore are continuously supplied to the applicator head and applied to the packages.
Another feature of the label-printing and application system of the invention is a label transporter for transferring printed labels from the printing operation to the label applicator. Transporting such labels after they have been removed or stripped from their backing or carrier tape has been troublesome in the past because of the adhesive on the back of the labels which is exposed after stripping. The transporter of the invention provides a series of guide rollers which contact the adhesive-coated backs of the labels but do not adhere to or pick-up the adhesive. These rollers cooperate with a moving belt which contacts the front or printed side of the labels so as to move the labels along between the belt and the rollers.
The invention will be described in greater detail by reference to the following description taken in connection with the accompanying illustrative drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front elevational view in perspective of an automatic selective label printing and applying apparatus employing the present invention;
FIG. 2 is a right side view of the apparatus shown in FIG. 1;
FIG. 3 is a partially schematic front elevational view of the label printing apparatus employed in conjunction with present invention;
FIG. 4 is a partially schematic front elevational view of the local transport and applicator apparatus of the invention;
FIG. 5 is a left side view of the apparatus shown in FIG. 4;
FIG.6 is a sectional view of the applicator assembly of the invention;
FIG. 7 is a bottom view of the core member of the applicator assembly shown in FIG. 6;
FIG. 8 is a plan view of the core member of the applicator assembly shown in FIG. 6;
FIG. 9 is a side view of the core member of the applicator assembly shown in FIG. 6; and
FIG. 10 is a sectional view of the core member shown in FIG. 9 taken along the line x--y thereof.
DESCRIPTION
FIG. 1 shows a complete label printing and applying system embodying the invention including an article or package feed or supply chute and conveyor means. The parts and components of this system may be assembled and mounted on a basic support or frame structure 1 which comprises a lower horizontally extending shelf member 3 supported on legs 5, 5' and provided with vertical support members 7, 7' on which is mounted an upper horizontally extending frame member 9. The upper horizontally extending frame member 9 may be mounted on the vertical support members 7, 7' at an angle of less than 90° with respect thereto to facilitate the mounting of a V-shaped conveyor system 11 with trough extending downwardly. There may be four vertical support members 7, 7' two each being mounted on each end of the lower shelf member 3, one of each pair being higher than the other to facilitate the angular disposition and mounting of the conveyor 11 as best shown in FIG. 2. Also mounted on the horizontally extending frame member 9 is a printer console 13 including a manual keyboard and control apparatus for selecting the indicia to be printed on labels and for electrically controlling the printing mechanism 15 (which is also shown schematically in FIG. 3). It will be understood that this label printing apparatus is considered as a complete unit which includes the printing mechanism 15, and the keyboard and the electrical control system 13 (console) therefor. Such printers may be of any commerically available type as exemplified by those manufactured and sold by Interface Mechanisms Company of Mountlake Terrace, Wash.
The conveyor system 11 comprises a continuous belt 17 adapted to be driven in one direction such as left to right as viewed in FIG. 1. The belt 17 is disposed at an angle to the horizontal (i.e., 45° ) so that it forms one side of a V-shaped trough which facilitates the transport of articles of various sizes and shapes and presents them properly and in the desired position to receive the label. The other side of the V-shaped trough is formed by a stationary plate member 19 which is co-extensive with the belt 17. The plate member 19 is provided with an opening 21 at a predetermined position therealong through which labels may be applied to the surface of packages of articles as they are carried along by the conveyor belt 17 across this opening. The conveyor belt is driven by an electric motor 23 and pulley system 25 and further description thereof is not provided herein in view of the highly developed and well known state of the art with respect to such conveyor belt drive systems.
Mounted below the conveyor belt system 11 is a printer mechanism 15 which includes a printer drum 26 on which is embossed in relief form a plurality of characters such as alphabetical letters, numerals, and symbols of any desired nature including those capable of forming or printing bar codes.
Adjacent and below the printer drum 26 is a supply reel 28 of pre-cut labels and backing tape 27 the labels being adhesively temporarily secured to the backing tape. The pre-cut labels and backing tape 27 is threaded up between a carbon ribbon 32 which passes around and is backed up by the printer drum 26 and printer hammers 29 with the blank surface of the labels facing the carbon ribbon 32. The labels are thus positioned to be impressed against the carbon ribbon 32 and the embossed characters on the printer drum 26 when the printer hammers 29 strike the back of the pre-cut labels and backing tape 27.
The character or symbol to be printed onto a label is selected by depressing the appropriate key on the console 13 which causes the take-up reel motor 31 to rotate and move the pre-cut labels and backing tape 27 until the selected label is between the carbon ribbon 32 and the printer hammers 29 which are then automatically actuated so as to forcibly drive a label that is between the hammers 29 and the carbon ribbon 32 (backed up by the printer drum 26) into contact with the selected character or symbol embossing on the drum 26 thereon so as to print the character on the label. The pre-cut labels and backing tape 27 move so as to successively position each selected character or symbol embossing at the proper place on the label. It will be understood that the printer drum 26 and the printer hammers 29 move extremely rapidly and are synchronized so that the printer hammers 29 strike the appropriate character embossing when it is properly positioned on the printer drum 26. By employing a printer drum 26 having one or more rows of character embossing labels may be printed having one or more rows of indicia, the rows being printed almost simultaneously.
After the label has been printed with the desired indicia it is then stripped from the backing tape 27 as this tape travels over the edge of stripping shoe 30 and changes its direction of travel by an angle in excess of 75°, for example, in a very small radius turn. As the tape 27 makes this turn it pulls away from the label whose upper end now freely extends upwardly the label being urged by continued travel of the backing tape 27 to move upwardly and enter the transport mechanism 40 for ultimate delivery to label applicator 41 of the invention to be described in greater detail hereinafter. The backing tape 27 minus the labels is then wound up on a take-up reel 31. It will be understood that the backing tape take-up reel 31 is adapted to be rotatably driven as is well known in the art of unwinding tape or film from a supply reel and winding the same up on a take-up reel. It will also be understood that movement of the backing tape 27 and the labels thereon is synchronized with the printer mechanism so that the printing operation does not start until a label is in proper position between the printer drum 26 and the printer hammers 29. Upon completion of the printing operation for each label, the backing tape take-up reel 31 rotates to move the printed label from the print position and place the next label to be printed at this position at which occurence rotation of the backing tape take-up reel 31 ceases.
Referring now to FIG. 4, the label transport system 40 is mounted on a plate member 43 which is adapted and designed to be secured to a base plate 45 which is secured at its lower end to the lower support shelf 3 and at its upper end to the upper horizontally extending support member 9. The plate member 43 is mounted on the base plate 45 as shown in FIG. 3 so that the lower end of the belt and roller wheel assembly of the transport system 40 shown in FIG. 4 is adjacent the point at which labels separate from the backing tape 27 and extend upwardly.
The transport system or assemblage 40 comprises a label transport belt 47 which passes around a first guide roller 49 and then upwardly at angle from the vertical to and around a second grooved guide roller 51. The belt 47 then passes downwardly and around a third roller 53 of larger diameter than that of the guide rollers 49 and 50 and fixedly mounted on its shaft for a purpose to be explained hereinafter. The belt 47 then travels upwardly around a fourth guide roller 55 and downwardly to the first guide roller 49. It will be understood that the label transport belt 47 is fabricated from any suitable material possessing frictional properties such as rubber, for example. This belt 47 may be substantially round in cross-section and of about 3/32 inch in diameter. The guide rollers 49, 51, 53, and 55 are also provided with similar grooves in which the label transport belt 47 travels and is retained in proper position on the guide rollers. The belt 47 and the guide rollers 49 and 51 are positioned and arranged so that the belt 47 will engage substantially only the middle portions of the labels which came into contact with the belt. Peripheral engagement of the labels by the transport belt 47 causes the labels to tip or tilt and results in jamming or erratic operation.
The transport mechanism 40 also includes an elongated flat guide bar member 57 which extends between the guide rollers 49 and 51 and acts as a firm backing and positioning plate for the label transport belt 47 during that portion of belt travel when the belt is engaging and moving the labels from the printer assembly 15 to the label applicator assembly 75 to be described in greater detail hereinafter. Associated with the label transport belt 47 and forming a part of the label transport assembly 40 is a series of label guide and retaining rollers 59 which are positioned along the path of the label transport belt 47 between the guide rollers 49 and 51. The label guide rollers 59 have lip portions at their upper and lower ends much like those of sewing thread spools. The distance between these lip portions is less than the width of the labels themselves and are equally spaced from the centerline of the belt 47. The label guide rollers 59 are of a material which does not adhere to or pick-up the adhesive on the back sides of the labels. A satisfactory material for this purpose is a fluorocarbon resin, for example, commercially available and sold as "teflon" which is a registered trademark of the manufacturer, E. I. Dupont de Nemours and Co., Wilmington, Del.
Coaxial with and fixedly mounted on the same shaft as the belt guide roller 53 is a pulley wheel 53' adapted to be driven bythe belts 63, 63' and 63" and the drive roller 65 which is one of a plurality of rollers which are driven by the pulley belt 67 as this belt drives the conveyor belt system 11 (not shown in FIG. 4). This is but one of several options available for driving the label transport belt 47 which could be driven by a separate electric motor, for example, provided for that purpose.
As shown the label transport system 40 comprising the label guide rollers 59 and the belt guide rod 57 may be mounted on a separate base plate 69 secured to the plate member 43 by means of quick mounting bolts 71 and 73, for example. This arrangement also allows adjustment for traction on labels and easy assembly and dis-assembly of the label transport system 40 for servicing and maintenance. The base plate 69 may be of the same material as the label guide rollers 59 so as to minimize the likelihood of picking-up the adhesive on the labels or sticking thereto.
As explained previously, as a label is separated from its backing tape 27, it moves vertically and its upper end extends through the space between the label transport belt 47 and the first of the label guide rollers 59. It is then carried upwardly between the belt 47 and the label guide rollers 59 with the adhesive coated surface of the label facing and being in contact with the label guide rollers 59. As the label makes its exit from the label transport mechanism 40, its upper end contacts a final label guide roller 76 which is spaced from the series of guide rollers 59 and positioned so that the label is forced to one side (i.e., the left side as shown in FIG. 4) and is drawn onto and retained by the label applicator head assembly 75 by means of a partial vacuum established at the lateral surface 78 of the applicator head 85.
Referring now to FIGS. 6 through 9, the applicator head assembly 75 comprises an external cylindrical cup-like member 85 mounted on a shaft 86 and over a cylindrical core member 87. The cylindrical member 85 (hereinafter called the applicator head) is provided on its surface with oppositely positioned flat portions 76 and 78, the area of these flat surfaces being of a size and shape conforming to the size and shape of the labels. These flat portions 76 and 78 may be referred to as label receiving-ejecting grids since each portion is gridded or perforated and, in operation is alternately internally connected to sources of sub-atmospheric and super-atmospheric air pressures as the applicator head 85 rotates from a label-receiving position to a label-ejecting position. At the label-receiving position a region of sub-atmospheric air pressure is established internally within and on one side of the applicator head 85 and is operative through the perforations in the grid surface (i.e., at portion 78) to receive and retain labels thereat. Upon 180° rotation of the applicator head 85, this grid portion (i.e., 78) is connected to a source of super-atmospheric air pressure which is internally established within the applicator head 85 and which is now operative through the aforesaid perforations to blow the label from this grid portion onto a package or article which has moved on the conveyor belt system 11 immediately adjacent and above the applicator head 85. It will be understood that labels are received and retained on the applicator head 85 with the indicia-bearing surface of the label being in contact with the gridded portion of the applicator head 85 and the adhesive-coated side of the label facing outwardly for impingement onto the article.
Upon 180° rotation of the applicator head 85 the opposite gridded portion 76 moves from the label-ejecting position to the label-receiving and retaining position so that the next label may be immediately supplied thereto. The applicator head 85 is caused to rotate by means of a drive motor 77 and pulley belt 79 with the belt 79 being in contact with the applicator head 85. The applicator head 85 is normally prevented from rotation by means of a ratchet-pawl combination 91, 81. The ratchet 91 is a cylindrical plate fixedly mounted on a shaft 95 which may be an integral hollow tubular extension on the end of the applicator head 85. The ratchet 91 is provided with two detents 91', 91". The pawl 81 rides against the ratchet 91 and prevents rotation of the applicator head by having its tip alternately engaging oppositely disposed detents 91', 91" in the ratchet 91. The pawl 81 is adapted to be partially rotated and momentarily swung out of engagement with the ratchet 91 by means of an electrical solenoid 83 as is well known in the art. The pawl 81 is momentarily withdrawn from and returned to engagement with the ratchet 91. Upon withdrawal of the pawl 81, it clears one of the detents (i.e., detent 91') so that the applicator head drive belt 79 and motor 77 are effective to cause the applicator head 85 to rotate until the second detent (i.e., 91") on the ratchet 91 comes into contact with the tip of the pawl 81 which again prevents further rotation of the applicator head 85. It will be understood that the solenoid 83 includes a spring-loaded shaft 82 pivotally secured to the pawl 81. Upon momentary application of current to the solenoid coils, the shaft 82 is drawn into the solenoid against spring resistance. Movement of the shaft 82 causes the pawl 81 to rotate slightly and out of contact with the ratchet 91. Upon cessation of the current application to the coils of the solenoid 83, the solenoid springs (not shown) immediately return the pawl 81 to its position of contact with the ratchet 91.
Referring now to FIGS. 6 through 10, the applicator assembly 75 includes, in addition to the applicator head member 85, a relatively solid core member 87, the ratchet 91 and a belt-driven pulley 93. As described herein before, the ratchet plate 91 is mounted on the end portion of the applicator head 85 and around the integral shaft extension 95 thereof. Mounted on top of the ratchet 91 is the pulley wheel 93 which is likewise mounted around the shaft portion 95 of the applicator head 85. The entire applicator assembly 75 is affixed to the base plate member 43 by means of a shaft or bolt 97 which extends through the hollow shaft 85 of the member 85 and is threaded into the base 43. Rotatable members comprising the applicator head 85, the ratchet 91, and the pulley 93 are rotatably retained in position around the shaft portion 95 by means of a nut 97' while the core member 87 is fixedly mounted against the base plate 43 so that it does not rotate.
The core member 87 is provided with a pair of ports 99 and 99' in the bottom thereof as shown in FIGS. 7 and 10. Each of the ports 99 and 99' is disposed over and in airtight communication with the conduits 96 and 96' (see FIG. 1) which are connected to a motor-driven air compressor or pump 107 which is mounted on the base shelf 3. The air compressor or pump 107 is of the type which is capable of establishing air under pressure greater than atmospheric as well as air at a pressure less than atmospheric. Hence, the air pressure at port 99 in the core member 87 is less than atmospheric while the air pressure at port 99' is greater than atmospheric.
The core member 87 is also supplied with two external channels 89 and 89' which extend circumferentially around its lateral side. These channels 89 and 89' are hermetically separated from communicating with each other by integral extensions 101 and 101' extending radially from the core member 87. When the rotatable cup member 85 is in place around the core member 87, the internal surface of the cup member 85 is substantially in hermetic contact with the radial extensions 101 and 101'. The channels 89 and 89' each communicate to whatever grid portion (76 or 78) of the applicator head 85 which is disposed thereover. Ports 99 and 99' in the bottom of the core member 87 communicate respectively to channels 89 and 89' by means of the internal channels 103, 103' provided in the core member 87. Thus, the channels 89 and 89' are always maintained at different air pressures, one being greater than atmospheric and one being less than atmospheric. One channel may thus be spoken of as the low pressure channel and the other channel may be referred to as the high pressure channel. When the grid portions 76 and 78 of the applicator head 85 are over these channels 89 and 89', the air pressure at the grid portion will be that of the channel beneath it and to which that grid portion communicates by and through the perforations therein. As the applicator head 85 rotates as described hereinbefore, each grid portion (76 and 78) thereof alternately communicates with the channels 89 and 89' so that the requisite air pressure condition may be established at the grid portions 76 and 78 depending upon whether that portion is in the label receiving-retaining position or in the label-ejecting position.
In operation, articles or packages are placed on the conveyor belt 17 and the operator selects the indicia desired for the first package by means of the console keyboard 13. When the package arrives at the photo-electric sensor 103 it interrupts a light beam which produces a signal which actuates the printing mechanism as described hereinbefore. The label for that package is printed, separated from the backing strip 27, and transferred by the label transport mechanism 40 to the label retaining surface 78 on the applicator 75. The package continues along the path of travel of the conveyor belt, its arrival at the photo-electric sensor 105 again interrupts a light beam which results in the production of an electrical pulse which is applied to the coils of the solenoid 83 so as to draw the shaft 82 down therein thus swinging the pawl 81 out of contact with the applicator 75. This permits the applicator head to rotate 180° or until the pawl 81 stops rotation thereof by contacting and abutting the succeeding detent on the ratchet 91. Actuation of the solenoid 83 is appropriately timed to permit applicator head 75 to rotate and present the label on the label retaining portion 78 in proper position as the package travels over an opening 21 in the package transport system 11. At this position of the applicator head, the label is blown onto the package.
There, thus, has been described a novel system for rapidly printing labels with any desired information thereon and applying these labels to the appropriate package or article. | A label printer and applicator including conveyor for continuously moving packages of different sizes and shapes from a loading point to a discharge point. Labels are selectively printed to bear any desired indicia such as pricing information, contents, or quantitites which may be uniquely applicable to any given package moving on the conveyor. Upon arrival of the package at a predetermind point along the conveyor the label, which may be uniquely applicable to that package, is affixed thereto by a novel label applicator. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to seatbelt systems and more particularly to seatbelt systems for automatically fastening a passenger restraining belt about a passenger.
2. Prior Art
Since seatbelt systems protect the passenger by restraining him in times of vehicular emergency, the safety of the passenger is good. However, because of the complexity, etc. of wearing belts, the proportion of seatbelt wearers is very low. For this reason, various types of systems which automatically fasten the belt about the passenger after he has seated himself are presently proposed.
Among these types of systems, those seatbelt systems which utilize a sprocket wheel turned by a motor and which drives a thick tape which engages with the sprocket wheel to automatically fasten the belt about the passenger are compact and are considered to be the most reliable. In these automatically fastened seatbelt systems, it is desirable that the sound level be controlled and the sprocket wheel and motor be provided in the lower portion of the front pillar or center pillar so that pleasant operation of the automatic fastening seatbelt system is possible.
SUMMARY OF THE INVENTION
Accordingly, it is a general object of the present invention to provide a seatbelt system wherein the thick tape extruded from the sprocket wheel is appropriately disposed so as to not be exposed to the interior of the vehicle.
It is also another object of the present invention to provide a seatbelt system whose assembly is easy and whose automatic fastening operation of the belt is not interfered with.
In accordance with the principles of the present invention, the objects are accomplished by a unique seatbelt system wherein the thick tape extruded by the sprocket wheel is extruded into a receiver space formed in the space between the top of the vehicle rocker panel and the interior lining.
BRIEF DESCRIPTION OF THE DRAWINGS
The above-mentioned features and objects of the present invetion will become more apparent with reference to the following description taken in conjunction with the accompanying drawings wherein like reference numerals denote like elements and in which:
FIG. 1 is a side view of the interior of the vehicle illustrating a first embodiment of the seatbelt device in accodance with the teachings of the present invention;
FIG. 2 is a cross sectional view along the line II--II in FIG. 1;
FIG. 3 is a partial close-up view illustrating a thick tape utilized in the present invention;
FIG. 4 is a partial close-up view illustrating the lower end of the front pillar;
FIG. 5 is an exploded close-up view illustrating the sprocket wheel and the sprocket housing;
FIG. 6 is a cross sectional view along the line VI--VI in FIG. 4;
FIG. 7 is a side view analogous to FIG. 1 which shows a second embodiment of the present invention; and
FIG. 8 is an interior close-up view illustrating the central pillar region.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIG. 1, shown therein is a seatbelt system in accordance with the teachings of the present invention. In FIG. 1, the seatbelt system includes a passenger restraining belt 10 which is brought diagonally into contact with the passenger 14 seated on a passenger seat 12 to thereby bring the passenger into a fastened in condition. The inner end 16 of the belt 10 is wound up by a retractor 20 which is fastened to the floor 18 of the vehicle. This retractor 20 retracts the inner end 16 of the belt 10 by its own power and is fitted with an inertial locking mechanism which can instantly stop the unwinding of the belt 10 in times of a vehicular emergency.
The outer end 22 of the belt 10, as shown in FIG. 2, is fastened to a runner piece 24. Wheels 26 are provided on the runner piece 24 and the automatic fastening and unfastening operation of the belt 10 is accomplished by the forward and backward motion of the runner piece 24 in a guide rail 28 which is fastened to a roof side panel 27. As is shown in FIG. 2, slide rail 30 is fastened to guide rail 28 and thick tape 34, as shown in FIG. 3, is provided in a slide groove 32 of the slide rail 30. The thick tape 34 is made from synthetic resin and since it is inserted into slide groove 32 with only minimal clearance, it is extensible and compressible, i.e. it may transmit either extensive or compressive forces longitudinally. Also, a plurality of openings 36 are formed at appropriate intervals along the length of the tape 34. A slide block 38 is fastened to one end and engages with the runner piece 24 so that the motive force of the thick tape 34 is transmitted to the runner piece 24.
As is shown in FIG. 1, a front end of a thin belt 40 is fastened to runner piece 24 and the back end of the thin belt 40 is wound onto retractor 42, fastened to roof side panel 27 at the rear end of guide rail 28. In the same manner as retractor 20, which winds up the inner end 16, the retractor 42 contains inertial lock mechanism which can instantly stop the unwinding of the belt 10 in times of the vehicular emergency.
As is shown in FIG. 1, the slide rail 30 extends towards the front of the vehicle further than the guide rail 28 and descends along the front pillar 44 of the vehicle. As is shown in detail in FIGS. 4 and 5, the slide rail is connected to a sprocket housing 48 which is fastened to the lower end of front pillar 44 and contains sprocket wheel 46. Furthermore, thick tape 34, which moves in the slide rail 30, engages sprocket wheel 46 within sprocket housing 48 by means of the openings 36.
Sprocket wheel 46 is caused to move by a reversible motor 50 mounted within the front pillar 44 and the output of motor 50 passes through the sprocket housing lid 52 to transmit motive power to the sprocket wheel 46 within.
Motor 50 is arranged to operate by detecting the entrance or exit of a passenger. For example, if the door is opened to allow the passenger to board or alight, the sprocket wheel 46 turns in a counterclockwise direction in FIG. 1; however, if the door is closed after the passenger is seated, it turns in a clockwise direction. In each of the above described instances, the motor revolves a fixed number of revolutions to cause the runner piece 24 to move forward or backward in the vehicle via the thick tape 34. As is shown in FIG. 4, one end of a second slide rail 54 is fastened to the sprocket housing 48. As is shown in FIG. 6, the other end of the second slide rail 54 is coupled to wire harness receiver 56. The wire harness receiver 56 is a space formed by a rectangular groove 62 formed by the top of rocker inner panel 60 which togethe with the rocker outer panel 58 forms a rocker panel assembly. Carpet 64 is the interior lining cover for the rocker inner panel 60. Wire harness 66, which supplies electricity to the tail lights, etc., power window wire harness 68, trunk opener cable 70 and fuel tank cap opener 72, etc. pass through the wire harness receiver 56.
Also, protector 74 is fastened over the wire harness receiver 56 before it is covered with carpet 64. The protector 74 is made up of a vertical piece 76 which separates carpet 64 from the sides of the wire harness, a horizontal divider piece 78 integral with the vertical piece 76 and a hook shaped lid 82 which is connected via one-piece hinge 80 of thin material to the top side of the vertical piece 76. It is desirable that these pieces be formed from one piece and fron synthetic resin. Furthermore, the hook shaped plate 82 is fastened from above the vertical weld shaped region 84 which is formed when the tops of the rocker outer panel 58 and the rocker inner panel 60 are welded together and as shown in the double-dotted interrupted line in FIG. 6, before assembly this may be bent perpendicular to divider piece 78 so that the thick tape 34 may be mounted on top of the divider piece 78.
When the hook-shaped lid 82 is fastened to the vertical joint 84, hook-shaped lid 82 and the vertical piece 76 form the boundary between the wire harness receiver 56 and the carpet 64 and wire harness receiver 56 is divided horizontally by the divider piece 78. The wire harnesses are inserted into the lower compartment and the thick tape 34 into the upper compartment. Here, it is best that the upper compartment be made with a cross-section greater than that of the thick tape 34 so that the thick tape 34 may freely slide longitudinally, i.e. towards the front or rear of the vehicle.
As shown in FIG. 6, one side of carpet 64 is pressed onto the top of hook-shaped lid 82 by scuff-plate 88 which is fastened to the outer rocker panel 58 by screws 86. In this way, by fastening a protector over the wire harness receiver 56 thick tape 34 may be securely and easily attached to the wire harness receiver. An interior roof lining 90 as shown in FIG. 2 and door panel 92 as shown in FIG. 6 are also provided.
For the purposes of description of the operation of the first embodiment, the position indicated by the solid lines in FIG. 1 shows the condition where the passenger 14 is seated in seat 12 and the belt 10 has been automatically fastened and under normal operating conditions, by belt 10 unwinding from the retractor 20 the passenger can easily change his driving position. Also, in emergency conditions such as a vehicular collision, retractors 20 and 42 instantly stop the unwinding of the inner end 16 and narrow belt 40 and the passenger is maintained in a securely restrained position by the belt 10 and his safety is guaranteed. Now, when the passenger exits and opens the door, motor 50 turns in a counterclockwise direction in FIG. 1 and causes sprocket wheel 46 to turn. The turning of sprocket wheel 46 causes thick tape 34 to move which in turn causes the outer end 22 of the belt 10 to move in the direction indicated by the arrow A via runner piece 24, i.e. as shown in the double-dotted interrupted line. Therefore, belt 10 is moved towards the front of the vehicle and separates from the passenger seat 12 to provide a passenger sufficient space to exit. One end of thick tape 34 is extruded from sprocket housing 48 into the second slide rail 54 by the rotation of the sprocket wheel. As is shown in FIG. 6, the extruded thick tape 34 moves to the rear of the vehicle through wire harness receiver 56 on top of divider piece 78. Since the thick tape 34 in wire harness receiver 56 is separated from the outside by divider piece 78 and hook-shaped lid 82, the passenger does not come into contact with the thick tape. Furthermore, since dust cannot enter the wire harness receiver 56, smooth operation of the thick tape 34 is quaranteed. Also, since thick tape 34 is protected by divider piece 78 and hook-shaped lid 82, even when wire harness receiver 56 is stepped on by a passenger, the movement of thick tape 34 is not affected.
When a passenger reenters and closes the door after sitting down, motor 50 reverses and thick tape 34 moves the outer end 22 towards the rear of the vehicle via sliding block 38 and runner piece 24. As a result, the belt 10 automatically fastens itself about the passenger as shown by the solid lines of FIG. 1. In this case, the thick tape 34 which is extruded into the wire harness receiver 56 from the sprocket housing 48 once more reverses and is extruded into slide rail 30 and passes through sprocket housing 48. As a result of the above described construction, the motion of the thick tape 34 is smooth.
Referring to FIGS. 7 and 8, shown therein is a second embodiment of the present invention. In this second embodiment the sprocket housing is fastened to the lower part of the center pillar 94. In addition, the center part of guide rail 96 runs horizontally along the roof side panel 27 but the front part descends towards the front of the car along the front pillar 44 and the rear end descends turning through a right angle down center pillar 94. Furthermore, in this second embodiment there is no retractor for moving runner piece 24 towards the rear of the vehicle or for stopping the motion of the runner piece 24 in a vehiclular emergency. The vertical part of guide rail 96 which runs down the center pillar 94 prevents the forward motion of the outer end 22 in a vehicular emergency. Furthermore, in this embodiment an anchor plate 98 is rotatably fastened to the runner piece 24 between the outer end 22 and runner piece 24. A slide rail 30, similar to that of the previously described embodiment, descends from the vertical part of guide rail 96 and is connected to the sprocket wheel 46 and a second slide rail 54, similar to that of the previous embodiment, descends from the sprocket wheel 46 and is connected to the wire harness receiver 56 such that, as in the previous embodiment, the thick tape extruded from the sprocket housing 48 can be received therein.
The remaining elements of the second embodiment are similar to that described above and a description of the operation and their interconnection of operation will be omitted. Furthermore, it should be apparent that this second embodiment operates and gives similar results to those obtained in the first embodiment.
As described above, in the seatbelt system of the present invention, since the remaining part of the thick tape passes into a wire harness receiver formed from the upper part of the inner rocker panel of the vehicle, the remaining portion of the thick tape 34 is appropriately disposed inside the body panel. Therefore, assembly is simplified and exposure of thick tape to the interior of the vehicle does not occur and deterioration and damage to the thick tape does not occur. Furthermore, since smooth motion of the thick tape is maintained by present invention, the reliability of the seatbelt system of the present invention is improved and excellent results are obtained.
It should be apparent to those skilled in the art that the above described embodiments are merely illustrative of but a few of the many possible specific embodiments which represent the application of the principles of the present invention. Numerous and varied other arrangements can be readily devised by those skilled in the art without departing from the spirit and scope of the invention. | A seatbelt system including a passenger restraining belt, a plastic tape coupled to one end of the passenger restraining belt which has a plurality of openings formed along its length, a sprocket wheel which engages with the plurality of openings in the plastic tape for moving the plastic tape and a motor for rotating the sprocket wheel whereby when the belt is moved, it is automatically fastened or unfastened. In addition, the seatbelt system includes a receiving space provided between the vehicle's rocker panel and an inner lining for receiving the remainder of the plastic tape after engagement with the sprocket wheel whereby the plastic tape will not project into the interior of the vehicle. | 1 |
BACKGROUND OF THE INVENTION
This invention relates to a shock-isolating, movable mounting device, for textile machine spindles, for instance for coiling and twisting machines and similar ones.
DESCRIPTION OF PRIOR ART
At present textile machine spindles are supported in pre-established positions along special frames without it being possible to move or shift the spindle itself relative to the textile machine frame.
The fixed upright arrangement of the spindles makes it hard to replace the cops by means of automatic mechanisms which require considerable headroom for the doffing of the cops themselves; this entails not just a machine of greater dimensions, but greater manufacturing costs too.
The fixed arrangement of the spindles renders their replacement also difficult in view of the proximity of the tangential control belt; the stopping of the spindle for its replacement or in order to replace the cop causes some trouble to the near-by spindles too since the disjunction of the tangential belt from a spindle alters the belt contact pressure and hence the control velocity for the adjoining spindles.
It is furthermore desirable to insulate each spindle to the utmost possible degree in order to absorb or reduce the vibrations which otherwise would be transmitted to the structure or frame of the textile machine.
In the past it has been suggested to provide a spindle mounting capable of rotating towards the outside of the machine upon an axis which is vertical and parallel to the axis of the spindle itself. Such an arrangement only partially solves the problem relative to the replacement of spindles and cops, since the upright position of the spindles still entails headroom problems; moreover the adoption of said mounting causes some difficulty in maintaining the right pressure of the tangential control belt. Finally the adoption of normal metal hinges has not solved entirely the problem relative to the complete insulation of the spindles, but rather it has worsened it due to the continuous wear which the metal hinge was subjected to over a length of time.
SUMMARY OF THE INVENTION
The object of this invention is therefore to supply a mounting for the spindles of a textile machine, by means of which it is possible to solve simultaneously both the problem relating to the complete dampening of vibrations, and the problem relating to the replacement of the spindles and cops themselves without influencing the adjoining spindles.
In accordance with the invention one has therefore provided a shock-isolating mounting for textile machine spindles which comprises: a mobile spindle bearing and the components which are necessary to hinge the bearing to the frame of the machine in order to turn the spindle over from an upright working position, where the spindle is in contact with a tangential control belt, to an inclined standing position, where the spindle is disengaged from the belt and is in contact with a braking device; said hinging components comprise at least a first hinging unit, made of elastomeric material, which defines a fixed horizontal axis, as well as at least a second hinging unit, made of elastomeric material, which defines a mobile horizontal axis which is parallel to the aforementioned one; a thrust unit which is hinged on the one side to the machine frame and which is toggle-jointed on the other side to the second above-mentioned hinging unit; one or more shock-isolating components, made of elastomeric material, which are interposed between one part of the mounting device and a fixed stopping surface in order to insulate the spindle completely in its working position.
Thanks to the above-mentioned shock-isolating bearing device one achieves the total insulation of the spindle vibrations from the spindle-carrying frame, and in general from the frame of the textile machine; hence the vibrations produced by possible unbalances of a spindle and/or a cop are no longer transmitted to the other spindles. Furthermore the movable resting device permits one to solve, in an extremely simple manner according to this invention, both the problem relating to the replacement of the cop in a limited amount of space available due to the inclined position which may be taken by the spindle, and the problem relating to the replacement of the spindle itself since the pulley of the latter detaches itself considerably from the tangential control belt without affecting the stretch of the belt itself.
BRIEF DESCRIPTION OF THE DRAWINGS
These as well as other characteristics of the shock-isolating, movable spindle bearing, according to this invention, shall be further illustrated hereinafter with reference to the figures of the drawings enclosed, of which:
FIG. 1 is a side view of a first way of realizing the supporting device according to this invention, the spindle being in its upright working position.
FIG. 2 is a plan top view of the supporting device of FIG. 1.
FIG. 3 is a side view, similar to that of FIG. 1, partly cutaway, and with the spindle inclined or moved in one of its resting positions.
FIG. 4 is a partially cutaway side view of a second form of realization of the movable supporting device for spindles according to this invention.
FIG. 5 is a partial view of a variation of the hinge.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
With reference to FIGS. 1 to 3 there is described a first form of realization of the spindle-supporting device according to this invention.
As shown, the supporting device comprises a mobile block or ring 1 which is hinged to a spindle frame 2 of a textile machine, in order to support a spindle 3 which is controlled by a tangential belt 4; a yarn cop 5 is carried by spindle 3 as indicated.
On the side of the spindle which is opposite the one in contact with the tangential belt 4, there is a brake shoe 6 supported by an elastic bearing 7 fastened to the spindle-supporting frame 2 of the machine.
In particular, as shown in the figures, the spindle-supporting block 1 is placed beneath the spindle-carrying frame 2 and is hinged to the latter upon a fixed horizontal axis which is defined, in this specific case, by two hinging components 8, made of elastomeric material; the hinging components 8 are coaxial and lie on a plane which is parallel to and behind the plane of tangential belt 4.
Two further hinging units 9, made of elastomeric material, define a second mobile hinging axis on the opposite side of the previous one.
The supporting device also comprises one or more thrust units, indicated globally by 10, each of which is hinged in 11 to a fixed point of the spindle-supporting frame 2, while on the other side it is toggle-jointed to a respective hinging component 9 made of elastomeric material which defines the aforementioned mobile horizontal hinging axis.
The drawing comprises finally a control lever 12, secured, for instance, to spindle-carrying block 1 in order to control manually, or by means of an automatic device, the turnover of the spindle from its upright working position shown in FIG. 1, to its inclined idle position shown in FIG. 3. Such turnover is made possible by the toggle-jointed movement in relation to the mobile axis, thus making the hinging axes 8,9,11 switch from the arrangement shown in FIG. 1 where the mobile or intermediate axis 9 is at one side of the plane passing through axes 8 and 11, to the arrangement shown in FIG. 3 where the three axes lie on the same plane, namely, the intermediate axis 9 is to be found on the opposite side of the plane relative to the one previously defined.
In the case of FIGS. 1-3 one has pointed out a manual control for supporting one spindle only but, it is nevertheless apparent that one will be able to design a manual or automatic control for several spindles simultaneously according to one's requirements.
If the position of FIG. 3 is again examined, it will be observed that each hinging component 8 and 9, made of elastomeric material, is made up in this specific case by a cylindrical body which is partially fitted into a half-cylindrical housing produced on one side of the spindle-carrying block or ring 1. Similarly, each hinging component 9, made of elastomeric material, is constituted by a cylindrical body which is partly fitted into a half-cylindrical housing produced at one end of thrust component 10 and respectively on one side of spindle-carrying block 1 which is placed opposite the previous one.
In both cases it is to be observed that the opposing surfaces of bracket 13, of spindle-carrying block 1, and respectively of thrust component 10, are never in direct contact but rather diverge with respect to each other in both upward and downward directions, relative to said hinging axes; such gauge is indispensible in order to maintain some clearance between the opposing surfaces, which clearance is sufficient to avoid their direct contact which, otherwise, would produce the propagation of the vibrations caused by the rotation of the spindle. Therefore, the vibrations produced by spindle 3 which is rotating by means of tangential belt 4 are totally dampened or absorbed by the elastomeric material hinging components 8 and 9, as well as by shock-isolating buffers or bearings 15 made of elastomeric material which intervene between a part of the supporting device, for instance, between spindle-carrying block 1 to which the aforementioned buffers are secured (FIG. 3) and a corresponding stop surface 16 of spindle-carrying frame 2 or of the textile machine.
In FIG. 3, the cutaway shows a particularly profitable form of realizing the thrust device 10; in this case thrust device 10 is elastically stressed by helical spring 17 against hinging component 9; each thrust component 10 is made up of a bush 18 hinged in 11 to frame 2, which may run telescopically relative to a bush 19 which is articulated to a respective component 9 of elastomeric material which defines the mobile hinging axis of the spindle bearing; it is obvious that, by adopting a spring 17 of suitable value and arranging the hinging axes at suitable pre-established distances, it is possible to obtain a thrust on supporting block 1, against surface 16 of the frame, which thrust is sufficient to keep spindle 3 firmly immobile in its upright working position shown in FIG. 1.
Briefly, the operation of the support device is as follows: in FIG. 1, the supporting device is shown during the spindle's working condition, namely, with spindle 3 standing upright in contact with tangential control belt 4. In this position, spindle 3 is made to rotate by belt 4 in order to uncoil the yarn off cop 5; it is readily apparent that under these conditions spindle 3 is supported in a totally insulated way from the rest of the machine since all possible vibrations of the spindle, produced for instance by unbalances of the yarn mass on cop 5, are dampened by elastomeric material hingings 8 and 9, as well as by the above mentioned insulating buffers 15. In the event of spindle 3 having to be stopped in order to replace it, or for ordinary servicing operations, as well as for the replacement of cop 5, it is sufficient to operate control lever 12 so as to press it downwards in order to turn the spindle over to the inclined position shown in FIG. 3. In fact, a downward pressure on lever 12 determines the rotation of the spindle-carrying block 1 around the fixed axis of the elastomeric material hinging components 8; such rotation takes place by overcoming the elastic reaction of the thrust component 10 as long as spindle 3 rests on brake 6 which stops it. In this position the spindle is considerably detached from the tangential control belt 4 having an inclined or fixed stop position since the three hinging axes supplied by components 8,9 and 11 are now coplanar, that is to say, the intermediate axis 9 is to be found on the opposite side of the aforementioned plane with respect to the previous position. It is obvious that the inclined arrangement of spindle 3 makes it easier to operate in order to disassemble and replace the spindle itself; it is also apparent that the arrangement of the spindle allows an inclined and front withdrawing of yarn cop 5 without interfering with possible overhead structures of the textile machine, for instance with a frame of overhead spindles.
FIG. 4 shows a simplified variation of the supporting device. In FIG. 4, one has employed the same numerical references as in previous figures to indicate similar or operationally equivalent components. Hence, also in the case of FIG. 4, the supporting block or ring 1 of spindle 3 is hinged, by means of a cylindrical component 8 made of elastomeric material, on the basis of a first fixed hinging axis. Furthermore, by means of another elastomeric material hinging component 9 which defines the mobile axis, it is toggle-jointed to thrust component 10 in the form of a lever which has its fulcrum 11 in the spindle-carrying frame 2 or a component which is integral with the latter. Number 1 again indicates a control lever, which in this case is integral with thrust lever 10. A shock-isolating bearing 20 is interposed between thrust lever 10 and a clasping component 21 which is above it. In the case of FIG. 4, unlike the previous case, the elastomeric material components 8 and 9, besides acting as a hinge and as shock-isolating components for the spindle's mounting, also supply the necessary elastic reaction in order to maintain block 1 with the spindle in a working position.
In the case of previous figures, the elastomeric material hinging components 8 and 9 were made of cylindrical bodies capable of producing a rotational type of hinge, that is to say, a hinge capable of allowing a relative rotation between the mounting components and the cylindrical components themselves.
Instead of the cylindrical components 8 and 9 made of elastomeric material, one may however use another type of hinging component, always made in elastomeric material; one may adopt, for instance, a component shaped like the one shown in FIG. 5, which would allow a flexing type of hinging, namely, one wherein the elastic flexing of the material itself is exploited in order to bring about a relative rotation, for instance of spindle-carrying block 1 in respect of supporting bracket 13, in the manner shown.
It is however apparent that what has been said and shown in the drawings enclosed has been supplied in order to exemplify the idea of the general solution entailed by this invention, which solution consists of a shock-isolating and overturning mounting for the spindles of a textile machine on the basis of which a spindle-supporting mobile block is hinged, with a toggle movement, by means of elastomeric material hinging components such as synthetic rubber or other similar materials, which are capable of acting as dampening or shock-isolating components, thus preventing any direct contact whatsoever between the spindle-supporting block 1 and the other clamping components of the textile machine. | Disclosed herein is a shock-isolating mounting for textile machinery spindles, which comprises a mobile resting block for the spindle with hinging components designed in order to move the spindle from an upright position, in which the spindle is in contact with a control belt, to an inclined position, in which the spindle is in contact with a brake; the above hinging components comprise some hinging units made of elastomeric material and a toggle-jointed thrust element connected in said manner to one of the aforementioned hinging components. | 3 |
BACKGROUND
[0001] When a formation is drilled under normal conditions, the well is almost always filled with drilling fluid that serves to carry rock cuttings to the surface, lubricate the drill bit, and provide an overpressure in the borehole to prevent the flow of formation fluids into the wellbore (i.e., a blow out). The overpressure provided by the drilling fluid also plays a key role in stabilizing the formation. As a result of the overpressure, the liquid part of the drilling fluid enters the formation (filtering) while the solid part accumulates at the formation surface (borehole wall). The accumulated solid contains materials (such as bentonite, for example) that act to form a hydraulic seal. The sealing layer is called “mudcake” and, once formed, prevents any further filtering of the drilling fluid into the formation. Thus, although a relatively small volume of the drilling fluid filters into the formation, the process is normally self-limiting.
[0002] Mudcake is able to form and sealing occurs because the pore size in the subsurface formation is smaller than the particle sizes in the drilling fluid. As a result, the bulk of those particles cannot pass through the pore entrance (though a small portion of very fine particles can pass and produce what is known as “fine invasion”). The bulk of the solid drilling fluid material is pressed against and sticks to the pore entrance and gradually builds the impermeable layer of mudcake. However, this process fails to occur when the size of the pore entrance is larger than the solid particles in the mud (drilling fluid). One common example is when fractures are encountered. Some natural fractures have apertures larger than the particles in the mud. This results in a fluid loss problem wherein a large volume of drilling fluid is lost into the formation, with its consequential economic and safety issues.
[0003] Fluid loss in fractures is manageable and remedial actions exist. One such remedy is to use solid materials in the drilling fluid that are proportionally larger. With this approach pore sizes of up to 2.5 millimeters have been sealed. More recently, the use of water swellable materials has been proposed. In this case, smaller, water swellable materials are used in the formulation of the mud. These materials enter the fracture, absorb water, and increase their volume, thereby forming a seal. Certain water swellable materials are capable of increasing their weight by over ten-fold in the course of a few hours. The rate and extent of swelling depends on the type of water available. The best results are obtained with fresh water.
[0004] A “super k layer”, also known as a “cavernous formation”, is a source of huge permeability and, when encountered during drilling, can take in large volumes of drilling fluid, even to the point there is not enough drilling fluid left in the borehole to reach the surface. This is referred to as “circulation loss”. Because super k layers have very large pores (on the order of tens of centimeter), there is no possibility of forming a mudcake at the borehole wall. As a result, the fluid loss can continue indefinitely so long as the fluid pressure in the borehole is higher than the fluid pressure in the formation.
SUMMARY
[0005] Sealing particles are used to stop or reduce undesired fluid loss. The sealing particles may be swellable or have effective cross-sectional areas greater than five square millimeters or are both swellable and have effective cross-sectional areas greater than five square millimeters. The sealing particles are disposed in one or more locations in which there is undesired fluid flow and, once lodged therein, stop or at least reduce the undesired fluid loss. A tubular having a bypass flow path may be used to deploy the sealing particles. The bypass flow path may use a biased or unbiased sleeve that is selectably movable to expose or block exit ports in the tubular. A retrievable sealing disk may be deployed to move the sleeve. The sealing particles may be made of a bi-stable material with extenders and may be actuated using swellable material. The sealing particles may extend in multiple dimensions.
[0006] This summary is provided to introduce a selection of concepts that are further described below in the detailed description. This summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used as an aid in limiting the scope of the claimed subject matter.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] The present disclosure is best understood from the following detailed description when read with the accompanying figures. It is emphasized that, in accordance with the standard practice in the industry, various features are not drawn to scale. In fact, the dimensions of the various features may be arbitrarily increased or reduced for clarity of discussion. Embodiments of determining are described with reference to the following figures. The same numbers are generally used throughout the figures to reference like features and components.
[0008] FIG. 1 is a schematic drawing showing a drilling operation in which a super k layer is encountered.
[0009] FIG. 2 is a schematic drawing showing a bottom hole assembly (BHA) having a bypass section or bypass opening, in accordance with the present disclosure.
[0010] FIG. 3 a is a schematic drawing, in end view, of a particle in a pore space, in accordance with the present disclosure.
[0011] FIG. 3 b is a schematic drawing, in cross-sectional view, of the particle in the pore space shown in FIG. 3 a , in accordance with the present disclosure.
[0012] FIG. 4 a is a schematic drawing, in side view, of a drill collar (or pipe) with exit ports, in accordance with the present disclosure.
[0013] FIG. 4 b is a schematic drawing, in cross-sectional view, of the drill collar shown in FIG. 4 a and a sleeve disposed therein, in accordance with the present disclosure.
[0014] FIG. 5 is a schematic drawing, in cross-sectional view, showing a sealing disk disposed in the sleeve of FIG. 4 b , in accordance with the present disclosure.
[0015] FIG. 6 is a schematic drawing, in cross-sectional view, showing an alternative embodiment of a sealing disk disposed in the sleeve of FIG. 4 b , in accordance with the present disclosure.
[0016] FIG. 7 a is a schematic drawing showing a short length of a bi-stable material in its straight form, in accordance with the present disclosure.
[0017] FIG. 7 b is a schematic drawing showing the short length of bi-stable material in FIG. 7 a in its curved shape, in accordance with the present disclosure.
[0018] FIG. 7 c is a schematic drawing showing the short length of bi-stable material in FIG. 7 b with other material added to the ends of the bi-stable material, in accordance with the present disclosure.
[0019] FIG. 7 d is a schematic drawing showing the short length of bi-stable material and other additional material in FIG. 7 c in its open or extended configuration, in accordance with the present disclosure.
[0020] FIG. 8 a is a schematic drawing showing the short length of bi-stable material and other additional material in FIG. 7 c with swellable material disposed in the interior region, in accordance with the present disclosure.
[0021] FIG. 8 b is a schematic drawing showing the short length of bi-stable material and other additional material with swellable material disposed in its interior region with the swellable material at least partially swelled, in accordance with the present disclosure.
[0022] FIG. 8 c is a schematic drawing showing the short length of bi-stable material and other additional material with swellable material disposed in its interior region with the swellable material completely swelled and the structure completely open, in accordance with the present disclosure.
[0023] FIG. 9 a is a schematic drawing showing an embedding object having at least two-dimensions in its closed configuration, in accordance with the present disclosure.
[0024] FIG. 9 b is a schematic drawing showing the embedding object of FIG. 9 a in its open configuration, in accordance with the present disclosure.
[0025] FIG. 10 is a workflow diagram for an embodiment to stop or reduce an undesired fluid flow using sealing particles, in accordance with the present disclosure.
[0026] FIG. 11 a is a schematic drawing showing two short lengths of bi-stable material in its curved shape joined to a common normal material, in accordance with the present disclosure.
[0027] FIG. 11 b is a schematic drawing showing the short lengths of bi-stable material in FIG. 11 a in their straight form, in accordance with the present disclosure.
[0028] FIG. 12 a is a schematic drawing showing a short length of a bi-stable material in its curved shape with normal material joined at different angles, in accordance with the present disclosure.
[0029] FIG. 12 b is a schematic drawing showing the short length of bi-stable material in FIG. 12 a in its straight form and the resulting non-linear structure, in accordance with the present disclosure.
DETAILED DESCRIPTION
[0030] It is to be understood that the following disclosure provides many different embodiments, or examples, for implementing different features of various embodiments. Specific examples of components and arrangements are described below to simplify the present disclosure. These are, of course, merely examples and are not intended to be limiting. In addition, the present disclosure may repeat reference numerals and/or letters in the various examples. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed. Moreover, the formation of a first feature over or on a second feature in the description that follows may include embodiments in which the first and second features are formed in direct contact, and may also include embodiments in which additional features may be formed interposing the first and second features, such that the first and second features may not be in direct contact.
[0031] Some embodiments will now be described with reference to the figures. Like elements in the various figures may be referenced with like numbers for consistency. In the following description, numerous details are set forth to provide an understanding of various embodiments and/or features. However, it will be understood by those skilled in the art that some embodiments may be practiced without many of these details and that numerous variations or modifications from the described embodiments are possible. As used here, the terms “above” and “below”, “up” and “down”, “upper” and “lower”, “upwardly” and “downwardly”, and other like terms indicating relative positions above or below a given point or element are used in this description to more clearly describe certain embodiments. However, when applied to equipment and methods for use in wells that are deviated or horizontal, such terms may refer to a left to right, right to left, or diagonal relationship, as appropriate. It will also be understood that, although the terms first, second, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another.
[0032] The terminology used in the description herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used in the description and the appended claims, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will also be understood that the term “and/or” as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items. It will be further understood that the terms “includes,” “including,” “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 or more other features, integers, steps, operations, elements, components, and/or groups thereof.
[0033] As used herein, the term “if” may be construed to mean “when” or “upon” or “in response to determining” or “in response to detecting,” depending on the context. Similarly, the phrase “if it is determined” or “if [a stated condition or event] is detected” may be construed to mean “upon determining” or “in response to determining” or “upon detecting [the stated condition or event]” or “in response to detecting [the stated condition or event],” depending on the context.
[0034] A system and method to prevent fluid loss from a pressurized region are described herein. A water swellable material may be used to seal a source of fluid loss such as a super k layer in a subsurface formation while drilling. The system and method may also apply to leaky tubing (i.e., tubulars) such as a pipe in which a leak has developed. As stated above, super k layers may have pore sizes on the order of tens of centimeters, which is very large. For such large pore sizes, the use of normal size water swellable materials becomes ineffective. However, larger particles (made from water swellable materials or not) may be constructed that are well-suited for sealing super k layers. Those larger particles can be delivered to the site of super k layers to provide a sealing surface.
[0035] FIG. 1 shows a scenario in which a drilling operation has encountered a super k layer 140 . The drill bit 120 has penetrated formation 150 in which layer 140 has large enough pores to qualify as a super k layer. Because of the extremely high permeability of layer 140 , the drilling fluid filling well 130 will flow into layer 140 until the pressure in well 130 equals (or drops below) the pressure in layer 140 . Since the pores in layer 140 are too large to be blocked by the solids in the conventional mud, no mudcake is formed to counteract this extreme invasion process.
[0036] To stop the flow of mud into the super k layer 140 , one may introduce materials into the drilling fluid that are on the order of or bigger than the pore sizes in the super k layer. During the normal operation of drilling, the drilling fluid containing the (typically-sized) solid particles are pumped through the central passageway 170 of the drill pipe 110 . The drilling fluid travels to the drill bit 120 in which special orifices (jets) 180 are cut, allowing the mud to leave passageway 170 and enter the annular region between the inner diameter of the wellbore 130 and the outer diameter of drill pipe 110 . For a six inch drill pipe, for example, the passageway 170 is about four inches in diameter, while the orifices 180 in the drill bit are generally less than one centimeter. The jets 180 are intentionally made small to create a jetting action. As a result, although larger particles could be introduced in the formulation of the mud and carried through central passageway 170 in drill pipe 110 , the orifices 180 in the drill bit 120 would prevent them from entering the annulus and coming into contact with the formation wall 130 . Currently there is no apparatus available that can deliver such large particles (i.e., greater than approximately one cm) to the bottom of the well. Thus, using existing technology, the largest particle sizes that can be delivered to the super k layer are limited by orifices 180 in drill bit 120 rather than the large central passageway 170 in drill pipe 110 .
[0037] To circumvent this limitation, one may choose from at least two possible courses of action. One is to use larger particles, but avoid sending those particles through the jetting holes (orifices) 180 . Another is to send smaller particles that can grow and become large on site, after they pass through orifices 180 . A possible third course of action may involve some combination of the first two.
[0038] FIG. 2 shows a bottom hole assembly (BHA) similar to that of FIG. 1 , but to which a bypass section or bypass opening 230 has been added. Bypass section 230 may employ many different mechanical designs that are conventionally used to stop or start a flow. Bypass section 230 has one or more holes 235 in the wall of drill pipe 110 that are large enough to allow desired large particles to pass into the annular region, thus bypassing jets 180 in drill bit 120 . In the embodiment of FIG. 2 , two holes 235 are shown that are diametrically opposed. The holes 235 open and close by rotating a cylindrical sleeve 210 that has matching holes 250 , but in which the remaining part of its cylindrical structure is solid. Under normal drilling operations, holes 235 are blocked by sleeve 210 , rotated to have its solid body facing holes 235 . When a super k layer or any layer with large pore or aperture size is encountered, the drilling process is stopped, the rotatable sleeve 210 is rotated (using, for example, a motor (not shown)) so that its holes 250 align with holes 235 in drill pipe 110 . This provides a new (temporary) flow path that offers much less resistance to flow, especially for large particles. The drilling fluid thus passes through the flow path formed by aligned holes 235 and 250 and enters the annulus. Under these conditions the drilling fluid may contain sealing particles that are only slightly smaller than the diameter of holes 250 or 235 , whichever is smaller. Those larger particles then serve to block the large pores in super k layer 140 and build a mudcake. Once a mudcake forms and the super k layer is sealed, the fluid loss is controlled and sleeve 210 may be rotated back to the closed position. That allows the mud to once again pass through the drill bit and, at this point, normal drilling operations can proceed.
[0039] FIGS. 3 a and 3 b show an example pore in the super k layer 140 that has been invaded by a particle that is sufficiently large that it can not move past a certain length into the super k layer 140 . The large particles may be constituents of a special drilling fluid that contains particles with sizes ranging from the size of particles found in normal drilling fluid up to the maximum size that the downhole equipment (such as one having a bypass section 230 ) can handle. A pore 310 has an aperture 340 . If the size of the large particle 320 is larger than aperture 340 , large particle 320 will at least partially block the aperture 340 , thereby reducing the effective aperture size, but not necessarily sealing the aperture, as smaller openings may still exist between aperture 340 and the blocking large particle 320 . That is, large particle 320 serves to at least reduce the flow into the super k layer dramatically, but may not stop it completely. However, with large particle 320 at least partially blocking aperture 340 , other, smaller particles in the mud can fill the resulting smaller effective aperture and particles can act in concert to form a seal and stop the undesired flow.
[0040] In some cases the size of aperture 340 near the wellbore may be larger than particle 320 , but a pore's size is generally not uniform and can reduce as one moves farther into the pore space, away from the borehole. A reduced pore size 350 , some distance into the formation, is conceptually illustrated in FIGS. 3 a and 3 b . Particle 320 may be small enough to initially pass through aperture 340 , but as the rush of the mud invasion into the super k layer 140 continues, particle 320 will be carried deeper into the super k layer 140 , where it eventually encounters a reduced aperture (pore throat) 350 . If the reduced aperture 350 is smaller than the size of particle 320 , particle 320 cannot pass beyond that point. While the entrapped particle 320 effectively further reduces the size of reduced aperture 350 , there may still be gaps 360 around particle 320 that remain unobstructed to fluid flow, similar to that described above. However, since the drilling fluid contains a distribution of particles having sizes ranging from small to large, the smaller particles can, as above, enter and seal off gaps 360 . Thus, when the large particle 320 is introduced to the super k layer 140 and gets stuck either at the pore face or in the pore throat at some point slightly removed from the borehole wall, it reduces the effective pore size and restricts the flow so that the remainder of the particles in the drilling fluid can seal the flow path, thereby stopping the invasion. In the example of FIGS. 3 a and 3 b , one large particle 320 is shown, but in practice there will be more. The combined effect of all will be more effective in sealing the super k layer 140 than the single particle shown.
[0041] In the embodiment just discussed, one delivers the large particles 320 to the super k layer 140 via the bypass section 230 . FIGS. 4 a and 4 b show an alternative embodiment of a bypass section 230 . Drill collar (or pipe) 110 in FIG. 4 a is provided with exit ports 410 to allow large particles 320 to pass through the drill collar 110 and enter the annulus. In FIG. 4 a one exit port 410 is shown, but, in general, more exit ports are possible and they can be located at various locations along the length of drill pipe 110 . The size and shape of exit ports 410 are selected to be larger than the largest particle 320 that is expected to be delivered to the formation. FIG. 4 b shows a cross-section of a drill collar 110 having two exit ports 410 . During normal drilling operation, those exit ports 410 are closed so that mud can pass down to and through the drill bit (as shown in FIG. 1 ). A sleeve 210 having no holes is provided that, during normal operations, forms a barrier to prevent the drilling fluid from exiting through exit ports 410 . Sleeve 210 is supported by a spring 420 that, during normal drilling operations, is maintained in a compressed, neutral, or elongated state that keeps exit ports 410 closed. When a super k layer 140 is encountered, sleeve 210 may be forced in a direction that compresses or elongates spring 420 . As a result, sleeve 210 moves past exit ports 410 , allowing the pumped fluid to enter the annulus. Once the pumping-to-seal operation is completed, sleeve 210 is returned to its normal operational position by the spring 420 , as shown in FIG. 4 b , whereupon normal drilling operations may resume.
[0042] One possible mechanism for displacing sleeve 210 is shown in FIG. 5 . In this embodiment, a sealing disk 510 is sent down from the surface. Disk 510 is attached to a cable 520 , enabling its retrieval once the pumping-to-seal operation is terminated. In operation, once a super k layer 140 is encountered, a rapid fluid loss reduces the fluid level in the well or at least reduces the fluid pressure. Once those symptoms are observed, disk 510 and cable 520 may be deployed through central passageway 170 of drill pipe 110 . Disk 510 has a diameter that is slightly smaller than the inner diameter of drill pipe 110 or sleeve 210 , according to particular embodiments. As a result, it forms a loose piston, pushing the old drilling fluid located below (i.e., ahead of) it through the drill bit. Behind (i.e., above) disk 510 , the fluid containing the large particles 320 is pumped into the well. The pumping pressure acts to push disk 510 down until it reaches bypass section 230 . Restriction dogs 430 may be located somewhere along sleeve 210 to reduce the effective diameter of drill pipe 110 or sleeve 210 . Restriction dogs 430 provide a surface on which disk 510 can seat and make a seal. The seal causes the pumping pressure to bear on sleeve 210 , forcing it downward and compressing (in this embodiment) spring 420 . Once sleeve 210 passes by exit ports 410 , the drilling fluid takes the less restrictive path into the wellbore and, from there, enters the adjacent super k layer 140 .
[0043] While this operation is in progress, drilling operations are stopped and the pressure is monitored. As the super k layer becomes more and more sealed by the large particle mud, the pressure in the mud column climbs until it reaches an expected level. At this point, some volume of normal drilling fluid is pumped into the well to flush the heavy particles 320 that did not get deposited in the super k layer out of the well. Cable 520 is then used to pull disk 510 up, breaking the disk 510 /restriction dog 430 seal. To facilitate the movement of disk 510 in the uphole direction, drilling fluid may be pumped into the annulus from the surface and withdrawn from central passageway 170 (this is the opposite flow direction from normal pumping operations). That helps prevent any cavitation effect caused by drawing disk 510 upward through the drilling fluid. Note in this embodiment disk 510 forms an effective barrier between the different fluids being pumped, similar to a plug. That is, it separates the “large particle drilling fluid”, having a full distribution of particle sizes, from the normal drilling fluid being used before a super k layer was encountered. This allows a metered volume of the large particle drilling fluid to be pumped into the well.
[0044] In an alternative embodiment (shown in FIG. 6 ), the length of disk 510 is chosen to be large to facilitate the downward motion of sleeve 210 . In particular, the length of disk 510 can be as long as sleeve 210 . If disk 510 is made of a dense material such as metal and the spring constant is chosen appropriately, disk 510 will weigh enough to compress spring 420 and expose exit ports 410 . In this embodiment, pumping pressure is not needed or at least is not the only mechanism available to compress spring 420 . Also in this embodiment, the large particle drilling fluid filling the volume above disk 510 can be delivered to the super k layer at pressures that are not excessive since the fluid is not used to compress the spring. That helps reduce further fluid loss.
[0045] In another embodiment sleeve 210 is attached to a motor that can be activated to slide the sleeve up or down to open exit ports 410 . The motor can be activated using mud pressure coding, for example, as is commonly used in directional drilling. The motor can also be connected to a flow or pressure sensor that senses, for example, the rapid loss of mud or a pressure drop.
[0046] In yet another embodiment, smaller particles are pumped into the fluid loss layer, such as a super k layer, but the particles are able to absorb another material, such as water, for example, and expand to increase their size. This is a common practice in fluid loss layers that have fractures with moderate aperture sizes. In this case, in a fashion similar to that shown in FIGS. 3 a and 3 b , the particles enter the pore space and, upon expanding, form a seal. Water swellable materials have been successfully used for fractures having aperture sizes on the order of one or two millimeters. In super k layers, however, the aperture is on the order of centimeters and the existing practice of using smaller particle swelling material does not work well. The time required for the water swellable particles to enter the fluid loss layer is much shorter than the time it takes them to swell and form an effective seal. For this scenario, it is preferable that the aperture of the fluid loss layer decreases as one moves away from the borehole wall to the point that its size becomes comparable to the size of the particles before swelling. If this is not the case, then the common practice is to allow a certain amount of the particles to enter the fluid loss zone and then shut off the well for a few hours, allowing time for the swellable particles to swell. Sealing apertures of up to 2.5 millimeters in diameter (i.e., pores having effective cross-sectional areas less than five square millimeters) has been accomplished in this manner.
[0047] In another embodiment, large water swelling particles are delivered to the super k layer using a by-pass apparatus such as is described above. In practice, a known volume of drilling fluid containing a distribution of larger particles is placed slightly above disk 510 , forming a first band of fluid, and delivered to a depth of interest. When ports 410 open, this fluid flows out of the drill pipe and into the super k layer. A second band can be a buffer layer of normal drilling fluid, followed by an activating band, which in most cases will be fresh water. The water swelling particles are known to absorb the fresh water and swell rather quickly. Delivering the fresh water to the super k layer having large swellable particles already in the pore structure expedites the swelling and causes a pressure seal to develop. Note that during this operation, the fluid pressure in the inner diameter of the drill pipe has to be higher than in the annulus to prevent the drilling fluid in the annulus from entering the interior region of the drill pipe. The pressure can be regulated by a combination of drilling fluid density and pumping speed.
[0048] Using (water) swellable particles allows the pre-swollen particles to be smaller and pass more freely through small passages than particles that are not swellable and of comparable size to the swollen particles. Smaller water swellable particles (e.g., 1-3 centimeters) can be delivered to the super k layer as described above. Those particles subsequently swell when they come in contact with fresh water and grow four to ten times in length. Thus, the effective particle size is on the order of ten to thirty centimeters. These particles are also more flexible and can form a better seal than conventional, non-swellable particles. The swellable materials not only are able to increase their size, but can also grow to conform to the inner diameter and shape of the pore in which they are disposed.
[0049] In yet another embodiment, use is made of bi-stable materials to fill up the pore space and create a hydraulic seal. Bi-stable structures are mechanical objects that are stable in two different shapes or configurations. A common and illustrative example of a bi-stable structure is a “snap” bracelet. That is, a straight piece of bi-stable material is gently struck against a person's wrist and the material “snaps” into its second stable form—an open loop that wraps around the wrist. Bi-stable materials are stable in both configurations, but retain residual stresses that can be used to trigger transitions to their alternate forms. In an embodiment contemplated to seal off freely flowing structures, the bi-stable particles initially resemble closed umbrellas. Those closed-configuration particles are pumped into the high permeability (freely flowing) structure. The particles are then triggered to open up like umbrellas, causing a large restriction in the flow path.
[0050] FIG. 7 a shows a short length of a bi-stable material 710 in its straight form. When the straight material of FIG. 7 a is pressed on its two ends, it is triggered and snaps to a curved shape 720 , shown in FIG. 7 b . The transition is reversible and if the two ends of the curved shape 720 are pushed open, the material snaps back to the linear shape 710 . In the example of FIGS. 7 a and 7 b , the length of the material is intentionally chosen to be short enough so that the object in FIG. 7 b does not form a complete or closed loop. If two pieces of normal material 730 are attached to the two ends of the object in FIG. 7 b , the object of FIG. 7 c is formed. The object of FIG. 7 c has rather large length but small width and behaves similar to the linear “closed umbrella” structure of FIG. 7 a . Note that the curvature of curved shape 720 has caused the distal ends of 730 pieces to come close to one another and may even be touching. If these two ends are pulled apart by some force, the curved shape 720 will snap to its straight form 710 and the structure 740 of FIG. 7 d is formed. This shape may have, for example, twice as much length as the object of FIG. 7 c , and despite its still small width may therefore behave similar to the “open umbrella” referred to above due to its increased length.
[0051] The triggering mechanism for the transition from bent (curved) to straight forms can be provided by (water) swellable materials. FIG. 8 a shows a composite structure 800 similar to that of FIG. 7 c , with water swellable materials 810 added to the interior region of the structure. Once this object comes into contact with water, the swelling of material 810 causes the two ends of normal material 730 to separate, forming the configuration shown in FIG. 8 b . The swelling continues until the two ends of curved shape 720 pass a transition zone and curved shape 720 snaps to the linear shape 710 of FIG. 7 a or 7 d.
[0052] Composite structures 800 can be made with small enough width to be pumped through inner passageway 170 of drill pipe 110 and pass through orifices 180 of drill bit 120 . Once these composite structures 800 are in the annulus, the rush caused by the invasion into the formation (rapid fluid loss) will convey them into the super k layer, where they will form random conglomerates by compaction. The band (volume) of mud containing composite structures 800 can be followed by a band of fresh water that will be absorbed by the water swellable particles 810 , causing them to expand and, in turn, causing curved shape 720 to snap to the increased length linear structure 815 ( FIG. 8 c ). This structure has large length and, depending on its orientation relative to the flow direction, can lodge inside the pore and restrict or even stop the flow.
[0053] When the increased length linear structure 815 is aligned with the flow direction, it may be carried by the flow deep into the super k layer. The deeper those particles invade the super k layer, the more fluid is lost. FIGS. 9 a and 9 b show another embodiment in which the embedding object is not linear and, once snapped open, will lodge in the pore. An example of a closed embedding object 910 is shown in FIG. 9 a in which two curved shape structures 720 are attached together to form a cross (when snapped to their linear forms). Four legs made of normal material 730 (three legs are shown in FIG. 9 a ) are attached to the four ends of the curved shapes 720 (ends of the cross). When the water swellable material 810 expands, it causes closed embedding object 910 to snap into open embedding object 920 ( FIG. 9 b ). The open embedding object 920 has four legs in a cross shape; thus, as soon as it snaps open and encounters a pore space of corresponding dimensions, it lodges in the pore, independent of its orientation relative to the fluid flow direction. This embodiment is not limited to four legs and structures with more than two cured shapes 720 attached together can be made that, when expanded, form a plurality of legs. Since the water swellable material expands in all directions, its unexpanded volume can be chosen such that when it swells, not only does it snap closed embedding object 910 open, but it also fills the entire cross section of open embedding object 920 and forms a very effective seal.
[0054] In the alternative embodiment shown in FIG. 11 a , curved shapes (i.e., bi-stable materials) 721 and 722 share (i.e., each connect to opposite ends of) a common piece of normal material 732 . In this case, the other ends of the curved shapes 721 , 722 attach to ends of normal material 731 , 732 , respectively. In this embodiment, the snapping point is not in the middle of the structure as it is for the open embedding object 920 . Rather, there are two snapping points offset from the middle of shared piece 732 . The curved configuration of FIG. 11 a is roughly the same length as that of FIG. 9 a , but, once in its snapped configuration ( FIG. 11 b ), it can be as much as one and a half times longer. Although an embodiment having two bi-stable material sections is shown in FIGS. 11 a , 11 b , other embodiments may have more bi-stable material sections joined to corresponding normal materials.
[0055] In the embodiments shown thus far, the straight (i.e., normal) materials are connected in line with the two ends of the curved material. These embodiments lead to straight structures when they are snapped open. In another set of embodiments, exemplified by that shown in FIGS. 12 a and 12 b , it is possible to connect the pieces 720 , 735 , 736 at different angles. In that case, the resulting snapped structure will not lie along a straight line. FIG. 12 b shows a snapped form in its non-linear configuration.
[0056] It is easy to see if the embodiments of FIGS. 12 a and 11 a are combined, it is possible to obtain three dimensional snapped forms that can be more effective in sealing large pores. That is, the embodiments shown in FIGS. 11 a , 11 b , 12 a , and 12 b may be extended to other dimensions, similar to that shown in FIGS. 9 a and 9 b , by joining, for example, multiple bi-stable materials together. The added dimensions may be more effective in trapping the structure within the pore space of the rock and facilitate the build up of a plug that can serve to block the fluid loss into the formation. In addition, the joining can be done using a normal material in addition to or instead of a bi-stable material.
[0057] FIG. 10 shows a flowchart or workflow to stop or reduce undesired fluid flow using sealing particles. Sealing particles that are swellable or have effective cross-sectional areas greater than five square millimeters or are both swellable and have effective cross-sectional areas greater than five square millimeters are provided ( 1002 ). The sealing particles are disposed in one or more locations in which there is undesired fluid loss ( 1004 ) and thereby stop or reduce the undesired fluid loss ( 1006 ).
[0058] The foregoing outlines features of several embodiments so that those skilled in the art may better understand the aspects of the present disclosure. Those skilled in the art should appreciate that they may readily use the present disclosure as a basis for designing or modifying other processes and structures for carrying out the same purposes and/or achieving the same advantages of the embodiments introduced herein. Those skilled in the art should also realize that such equivalent constructions do not depart from the scope of the present disclosure, and that they may make various changes, substitutions, and alterations herein without departing from the scope of the present disclosure.
[0059] The Abstract at the end of this disclosure is provided to comply with 37 C.F.R. §1.72(b) to allow the reader to quickly ascertain the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.
[0060] While only certain embodiments have been set forth, alternatives and modifications will be apparent from the above description to those skilled in the art. These and other alternatives are considered equivalents and within the scope of this disclosure and the appended claims. Although only a few example embodiments have been described in detail above, those skilled in the art will readily appreciate that many modifications are possible in the example embodiments without materially departing from this disclosure. Accordingly, all such modifications are intended to be included within the scope of this disclosure as defined in the following claims. In the claims, means-plus-function clauses are intended to cover the structures described herein as performing the recited function and not only structural equivalents, but also equivalent structures. Thus, although a nail and a screw may not be structural equivalents in that a nail employs a cylindrical surface to secure wooden parts together, whereas a screw employs a helical surface, in the environment of fastening wooden parts, a nail and a screw may be equivalent structures. It is the express intention of the applicant not to invoke 35 U.S.C. §112, paragraph 6 for any limitations of any of the claims herein, except for those in which the claim expressly uses the words ‘means for’ together with an associated function. | Sealing particles are used to stop or reduce undesired fluid loss. The sealing particles may be swellable or have effective cross-sectional areas greater than five square millimeters or are both swellable and have effective cross-sectional areas greater than five square millimeters. The sealing particles are disposed in one or more locations in which there is undesired fluid flow and, once lodged therein, stop or at least reduce the undesired fluid loss. A tubular having a bypass flow path may be used to deploy the sealing particles. The bypass flow path may use a biased or unbiased sleeve that is selectably movable to expose or block exit ports in the tubular. A retrievable sealing disk may be deployed to move the sleeve. The sealing particles may be made of a bi-stable material with extenders and may be actuated using swellable material. The sealing particles may extend in multiple dimensions. | 2 |
FIELD OF THE INVENTION
The present invention relates to a connection component designed to be mounted on a tubing assembly for connecting the tubing assembly to a prefilled, foil-sealed container, and in particular to a connection component which includes a spike for penetrating the foil seal and an air vent having a flexible membrane therein. The present invention is also generally related to a copending application filed on Aug. 30, 1988, Ser. No. 239,044 now U.S. Pat. No. 4,888,008 granted Dec. 19, 1989, which is a continuation of an application filed on Mar. 3, 1987, Ser. No. 021,181 entitled "Vented Spike Connection Component" assigned to Sherwood Medical Company.
BACKGROUND OF THE INVENTION
In an enteral fluid delivery system for a patient, there is a need to provide a connecting component which will effect a quick connection of the fluid delivery set to a prefilled, foil-sealed container containing enteral fluid. In these fluid delivery systems, the connecting component is preferably a cap, which replaces the shipping cap on the prefilled container when the container is connected to the fluid delivery set for administration of the enteral fluid to the patient. The connecting component preferably includes a means for perforating the foil diaphragm on the container during attachment of the fluid delivery set to the container to simplify the assembly of the delivery system. It is further desireable that the connecting component provide a means to allow air to vent into the container as the enteral fluid flows from the container. This venting means should be designed to allow filtered air to flow into the container while preventing the air from flowing into and through the fluid passageway. Additionally, the venting means must prevent the passage of enteral fluid from the container through the air passageway.
One approach is illustrated in U.S. Pat. No. 3,542,240, issued to Solowey on Nov. 24, 1970. The first embodiment of Solowey illustrates the use of a single, centrally positioned projection designed to puncture the diaphragm of the container. The projection includes parallel air and liquid passageways therein to allow vented air to flow into the container while the fluid is administered to the patient. Additionally, Solowey illustrates the use of a check valve consisting of a steel ball and coil spring moveably positioned within the air passageway. Finally, the Solowey device includes a circular flange on the bottle which engages a flexible sleeve on the cap to prevent the removal of the cap during the operation of the administration set. Another embodiment of Solowey illustrates the use of a pair of parallel, spaced apart air and liquid passageways therein.
The present invention seeks to provide a connection component for effecting a quick and reliable coupling between the fluid delivery set and the prefilled, sealed container. The present invention minimizes the potential for contamination of the container by providing an efficient means for puncturing the foil diaphragm of the container while simultaneously tearing the diaphragm to create a passageway therein to allow for the flow of vented filtered air therethrough.
SUMMARY OF THE INVENTION
An advantage of the present invention is that the connection component will puncture the protective diaphragm on the enteral fluid containing container as the connection component is being attached to the top of the container.
Another advantage of the present invention is that the air passageway is spaced apart from the liquid passageway to prevent the vented air from flowing into the liquid passageway.
Another advantage of the present invention is that the air passageway includes a flexible membrane therein to allow filtered air to flow into the enteral fluid container while preventing enteral fluid from leaking out of the container through the air passageway.
Another advantage of the present invention is that the spike member is offset from the center of the cap so that as the cap is attached to the container, the spike member will tear the diaphragm to create a passageway therein for the vented air.
Another advantage of the present invention is that the opening of the air passageway is recessed from the diaphragm on the container to ensure that the diaphragm does not obstruct the flow of air from the air passageway.
The present invention provides a connection component which consists primarily of a cap specifically designed for attachment to the top opening of an enteral fluid containing container. The cap includes a spike member which extends inwardly from the body of the cap toward the container. The spike member is offset from the center of the cap body and includes a fluid passageway therein to allow for fluid communication between the container and the fluid delivery set. The cap further includes an air vent offset from the center of the cap body and oriented opposite the opening of the spike member. A flexible membrane is positioned adjacent to the inner opening of the air vent to allow the passage of air into the container while preventing enteral fluid from leaking out of the container through the air vent.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an enlarged cross-sectional view of the connection component of the present invention;
FIG. 2 is an enlarged cross-sectional view of the flexible disk and air passageway of the present invention shown in FIG. 1;
FIG. 3 is a top view of the foil diaphragm of the prefilled container after the diaphragm has been penetrated by the connection component of the present invention;
FIG. 4 is an exploded perspective view, partly in section taken along lines 4--4 of FIG. 6;
FIG. 5 is a partial cut-away view illustrating the connection component attached to the container and tubing of the present invention; and
FIG. 6 is a bottom view of the connection component of the present invention.
FIG. 7 is a partial cut-away view illustrating the connection component piercing the foil diaphragm of the prefilled container.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
One form of the present invention is illustrated in the drawings and is described generally herein as a connection component or cap 10. The cap 10 includes a top surface 12, a bottom inside surface 14 and a rim 16 adapted to be removably mounted on the neck 18 of a prefilled container 20. The cap 10 is preferably of a one-piece construction formed from a molded plastic such as styrene.
The top surface 12 includes a pair of cylindrically shaped first and second members, 22 and 24, respectively, extending outwardly from the top surface 12 of the cap 10. Both members, 22 and 24, are offset from the central axis C1 of the cap 10, with the second member 24 being positioned midway between the central axis C1 of the cap 10 and one side of the cap 10, while the first member 22 is offset slightly from the central axis C1 of the cap 10. The first member 22 includes an internal liquid passageway 26 and is adapted to be attached to a plastic tubing 28 which, along with the cap 10, forms part of the fluid delivery set. The second member 24 includes an internal air passageway 30 and a standard filter (not shown) which allows filtered air to flow into the prefilled container 20.
The bottom inner surface 14 of the cap 10 includes a spike member 32 which is formed by truncating the cylindrically shaped first member 22 at an angle starting at a location near the bottom inside surface 14 of the cap 10 and extending to an apex 34. The apex 34 of the spike member 32 extends beyond the bottom edge of the rim 16. The apex 34 is aligned on the bottom inside surface 14 of the cap 10 adjacent to the central axis C1 of the cap 10 while the opposing side 36 of the spike member 32 is positioned away from the central axis C1 of the cap 10 and in alignment with the apex 34 and central axis C1. The liquid passageway 26 in the first member 22 extends through spike member 32 to allow fluid communication between the tubing 28 and the container 20.
The bottom inside surface 14 of the cap 10 further includes first and second recesses, 42 and 44 respectively, and a flexible disk 38. The first recess 42 extends along nearly the entire bottom inside surface 14 of the cap 10 to provide a spaced apart relationship between the bottom inside surface 14 of the cap 10 and the diaphragm 46 on the container 20. The second recess 44 is positioned generally between the apex 34 of the spike member 32 and the rim 16 of the cap 10. The air passageway 30 of the second member 24 opens into the second recess 44 between the center of the second recess 44 and the rim 16 of the cap 10. The flexible disk 38 is retained in the second recess 44 by a spike shaped retainer 40. The retainer 40 is melted thermally or ultrasonically to retain the flexible disk 38 in the second recess 44. The flexible disk 38 is preferably constructed of a soft plastic or elastomeric, non-porous, material and is designed to overlap the rim of the second recess 44.
As illustrated in the drawings, the cap 10 has a central axis designated as C1, about which the cap 10 is rotated for attachment to the container 20. As further illustrated in the drawings, first and second members 22 and 24, respectively, are both offset from the central axis C1 and extend upwardly from the top surface 12 of the cap 10. Additionally, the apex 34 of spike member 32 on the bottom inside surface 14 of the cap 10 is oriented so that the opening of the liquid passageway 26 faces away from the opening of the second member 24. The center of the liquid passageway 26 in the first member 22 is designated in the drawings as axis C2. Axis C2 of the liquid passageway 26 is offset from the central axis C1 by approximately 0.1 inch (2.5 mm). The center of the air passageway 30 in the second member 24 is designated in the drawings as axis C3. Axis C3 of the air passageway 30 is offset from the axis C2 of the liquid passageway 26 by approximately 0.5 inch (12.7 mm). This aligned separation of the respective passageways, along with the orientation of the apex 34 on the spike member 32 effectively prevents air bubbles from flowing directly into the liquid passageway 26 of the first member 22.
With this preferred orientation of the spike member 32 and the first and second recesses, 42 and 44 respectively, of the present invention, air is drawn into the air passageway 30 of the second member 24 without significant obstruction by the diaphragm 46. As illustrated in FIG. 3, the diaphragm 46 is deformed and torn by the offset spike member 32 to provide an opening in the diaphragm 46 which is sufficiently extended to permit fluid to flow freely through the liquid passageway 26 in the first member 22 into the tubing 28 and to allow air to flow freely through the second member 24 into the container 20. The first recess 42 ensures that the flexible disk 38 will be spaced apart from the diaphragm 46 a sufficient distance so that the flexible disk 38 is allowed to flex in response to the passage of air from the air passageway 30 into the container 20. The second recess 44 causes the flexible disk 38 to be biased slightly towards the inside of the container 20 and ensures that the air bubbles are deflected away from the liquid passageway 26.
The cap 10 of the present invention forms an integral part of an improved fluid delivery set. The enteral fluid containing container 20 is typically delivered with a specially designed shipping cap which must be removed prior to the attachment of the cap 10 on the container 20. In the preferred embodiment, the cap 10 is threaded onto the neck 18 of the container 20. As the cap 10 is threaded onto the container 20, the spike member 32 pierces the protective diaphragm 46 in the manner illustrated in FIG. 3. Next, the tubing 28 is attached to the first member 22 on the top surface 12 of the cap 10. The container 20 is then inverted and the air is removed from the tubing 28. Finally, the safety cap 48 is removed from the second member 24 to allow the air passageway 30 to communicate through a filter (not shown) between the atmosphere and the interior of the container 20. The delivery set is now ready to administer the enteral fluid to the patient.
In operation, the enteral fluid flows from the container 20 through the liquid passageway 26 into the tubing 28. As this occurs, filtered air is drawn into the air passageway 30 through the second member 24. The air will flow through the air passageway 30 and bubble past the flexible disk 38. By extending the flexible disk 38 beyond the perimeter of the second recess 44, the flexible disk 38 operates as a flexible barrier against the bottom inside surface 14 of the cap 10 to direct the air bubbles away from the opening of the liquid passageway 26 in the container 20. The flexible disk 38 also prevents the loss of enteral fluid from the container 20 through the air passageway 30 by pressing against the second recess 44 whenever the pressure inside the container 20 is greater than the atmospheric pressure.
The detailed description of the preferred embodiment of the invention having been set forth herein for the purpose of explaining the principles thereof, it is known that there may be modifications, variations or changes in the invention without departing from the proper scope of the invention as defined by the claims attached hereto. | A connection component suitable for use with an enteral fluid delivery set wherein the connection component consists of a threaded cap having a projecting spike thereon to penetrate and deform a foil diaphragm on the fluid container and further including an air passageway having a flexible member therein to allow filtered air to flow into the fluid container while preventing the flow of fluid from the fluid container through the air passageway. | 0 |
TECHNICAL FIELD
[0001] Embodiments described herein generally relate to reduction of the overall detectable unrecoverable FIT rate of a cache in microprocessor-based systems.
BACKGROUND
[0002] As cache memory sizes increase, cache structures tend to be more vulnerable to soft errors (SER) and detectable unrecoverable errors (DUE), due to the cache retaining modified data for a longer length of time. If a soft error corrupts a modified cache line, the line's data cannot be retrieved or correctly written back. First level cache is the largest contributor to the DUE FIT rate in a cache memory system. What is needed is a cache replacement policy that addresses reducing the residency time of dirty lines in a cache in order to achieve a reduced DUE FIT rate.
BRIEF DESCRIPTION OF THE DRAWINGS
[0003] FIG. 1 illustrates a multiprocessor system used in conjunction with at least one embodiment;
[0004] FIG. 2A illustrates a multi-core processor used in conjunction with at least one embodiment;
[0005] FIG. 2B illustrates a multi-core processor used in conjunction with at least one embodiment;
[0006] FIG. 3 illustrates a cache controller used in conjunction with at least one embodiment;
[0007] FIG. 4 illustrates one embodiment of a method of modifying an algorithm in order to reduce DUE FIT rate;
[0008] FIG. 5 illustrates one embodiment of a method of modifying an algorithm at core level to guarantee DUE FIT rate; and
[0009] FIG. 6 illustrates a representation for simulation, emulation and fabrication of a design implementing the disclosed techniques.
DESCRIPTION OF EMBODIMENTS
[0010] At least one embodiment includes a processor including a core data cache and cache control logic to receive a hit/miss signal from the core cache and initiate a core cache eviction in response. The cache control logic may receive a read/write signal from a load store unit or address generation unit, and an eviction policy signal indicative of a detectable unrecoverable error failure in time (DUE FIT) rate of the core data cache. In at least one embodiment, the eviction policy signal influences the selection of a line to evict in response to a cache miss. Responsive to a relatively high DUE FIT rate, the eviction policy may be modified to encourage the eviction of modified lines from the cache. When DUE FIT rate is low, the eviction policy may be relaxed so that modified lines are effectively to remain in the cache longer. The eviction policy may be implemented in stages with an intermediate stage attempting to prevent an increase in the number of modified lines in the core data cache and an aggressive stage to decrease the number of modified lines.
[0011] In at least one embodiment, the processor includes age modification logic to influence the cache eviction policy to preferentially evict modified lines based at least in part on the current estimated DUE FIT rate. The cache replacement policy may include multiple levels of aggressiveness with respect to evicting modified data from the core data cache. In at least one embodiment, an aggressive eviction policy is employed when the DUE FIT rate exceeds a specified threshold. The aggressive policy preferentially evicts modified lines for all cache miss events. If the DUE FIT rate is below the first threshold, but exceeds a lower threshold, one embodiment triggers and intermediate eviction policy under which modified lines are preferentially evicted when a cache write miss occurs, but employs a preexisting eviction policy, including but not limited to a least recently used policy, a pseudo LRU policy, a least recently filled policy, and a pseudo least recently filled policy. If the DUE FIT rate is below both thresholds, a relaxed policy may be invoked under which the recency based eviction policy is unmodified.
[0012] In at least one embodiment, modified lines are preferentially evicted by age modification logic that appends one or more most significant bits to an age field or age attributed employed by the recency based eviction logic. In these embodiments, the age modification logic may force the age-appended bits to 1 under and aggressive policy for all modified lines, while asserting the age-appended bits for modified lines only in response to a write miss under the intermediate eviction policy. The intermediate eviction policy effectively ensures that the number of modified lines on average does not increase. The eviction policies, age modifications, and DUE FIT estimates may be made on a per-core basis in a multicore cache. In these embodiments, a first core may operate under a first eviction policy if its DUE FIT rate is low or its DUE FIT target is high, while another core operates under a more aggressive policy if its DUE FIT rate is high or its target is lower.
[0013] In at least one embodiment, a cache eviction method includes obtaining DUE FIT data indicative of a DUE FIT rate, comparing the DUE FIT rate to a first threshold, and responsive to the DUE FIT rate exceeding the first threshold, evicting modified lines preferentially in response to all cache miss events. In some embodiments, the DUE FIT rate not exceeding the first threshold, but exceeding a second threshold, evicting modified lines in response to write miss events and evicting based on a recency policy otherwise. In one embodiment, a relaxed eviction policy, wherein lines are evicted based on a recency policy in response to cache miss events is set in response to the DUE FIT rate not exceeding the second threshold. further comprising, estimating the DUE FIT RATE based on an estimate of the number of modified lines.
[0014] In the following description, details are set forth in conjunction with embodiments to facilitate discussion of the disclosed subject matter. It should be apparent to a person of ordinary skill in the field, however, that the disclosed embodiments are exemplary and not exhaustive of all possible embodiments.
[0015] Throughout this disclosure, a hyphenated form of a reference numeral refers to a specific instance of an element and the un-hyphenated form of the reference numeral refers to the element generically or collectively. Thus widget 12-1 refers to an instance of a widget class, which may be referred to collectively as widgets 12 and any one of which may be referred to generically as a widget 12.
[0016] Embodiments may be implemented in many different system types and platforms. FIG. 1 illustrates a multi-core processor used in conjunction with at least one embodiment. In at least one embodiment, system 100 includes a multi-processor system that includes a first processor 170 - 1 and a second processor 170 - 2 . While some embodiments, include two processors 170 , other embodiments may include more or fewer processors. In at least one embodiment, each processor 170 includes a core region 178 and an uncore region 180 . In some embodiments, core region 178 includes one or more processing cores 174 . In at least one embodiment, uncore region 180 includes a memory controller hub (MCH) 172 , a processor-hub point-to-point interface 176 , and a processor-processor point-to-point interface 173 .
[0017] In at least one embodiment, MCH 172 supports bidirectional transfer of data between a processor 170 and a system memory 120 via a memory interconnect 182 . In some embodiments, system memory 120 may be a double-data rate (DDR) type dynamic random-access memory (DRAM) while memory interconnect 182 and MCH 172 may comply with a DDR interface specification. In at least one embodiment, system memory 120 - 1 may include a bank of memory interfaces populated with corresponding memory devices or boards.
[0018] In at least one embodiment, system 100 is a distributed memory embodiment in which each processor 170 communicates with a local portion of system memory 120 . In some embodiments, system memory 120 - 1 is local to processor 170 - 1 and represents a portion of the system memory 120 as a whole, which is a shared memory space. In some embodiments, each processor 170 can access each portion of system memory 120 , whether local or not. While local accesses may have lower latency, accesses to non-local portions of system memory 120 are permitted in some embodiments.
[0019] In some embodiments, each processor 170 also includes a point-to-point interface 173 that supports communication of information with a point-to-point interface 173 of one of the other processors 170 via an inter-processor point-to-point interconnection 151 . In some embodiments, processor-hub point-to-point interconnections 152 and processor-processor point-to-point interconnections 151 are distinct instances of a common set of interconnections. In other embodiments, point-to-point interconnections 152 may differ from point-to-point interconnections 151 .
[0020] In at least one embodiment, processors 170 include point-to-point interfaces 176 to communicate via point-to-point interconnections 152 with a point-to-point interface 194 of an I/O hub 190 . In some embodiments, I/O hub 190 includes a graphics interface 192 to support bidirectional communication of data with a display controller 138 via a graphics interconnection 116 , which may be implemented as a high speed serial bus, e.g., a peripheral components interface express (PCIe) bus, or another suitable bus.
[0021] In some embodiments, I/O hub 190 also communicates, via an interface 196 and a corresponding interconnection 156 , with a bus bridge hub 118 that supports various bus protocols for different types of I/O devices or peripheral devices. In at least one embodiment, bus bridge hub 118 supports a network interface controller (NIC) 130 that implements a packet-switched network communication protocol (e.g., Gigabit Ethernet), a sound card or audio adapter 132 , and a low bandwidth bus 122 (e.g., low pin count (LPC), I2C, Industry Standard Architecture (ISA)), to support legacy interfaces referred to herein as desktop devices 124 that might include interfaces for a keyboard, mouse, serial port, parallel port, and/or a removable media drive. In some embodiments, low bandwidth bus 122 further includes an interface for a nonvolatile memory (NVM) device such as flash read only memory (ROM) 126 that includes a basic I/O system (BIOS) 131 . In at least one embodiment, system 100 also includes a peripheral bus 123 (e.g., USB, PCI, PCIe) to support various peripheral devices including, but not limited to, one or more sensors 112 and a touch screen controller 113 .
[0022] In at least one embodiment, bus bridge hub 118 includes an interface to a storage protocol bus 121 (e.g., serial AT attachment (SATA), small computer system interface (SCSI)), to support persistent storage 128 , including but not limited to magnetic core hard disk drives (HDD), and a solid state drive (SSD). In some embodiments, persistent storage 128 includes code 129 including processor-executable instructions that processor 170 may execute to perform various operations. In at least one embodiment, code 129 may include, but is not limited to, operating system (OS) code 127 and application program code. In some embodiments, system 100 also includes nonvolatile (NV) RAM 140 , including but not limited to an SSD and a phase change RAM (PRAM).
[0023] Although specific instances of communication busses and transport protocols have been illustrated and described, other embodiments may employ different communication busses and different target devices. Similarly, although some embodiments include one or more processors 170 and a chipset 189 that includes an I/O hub 190 with an integrated graphics interface, and a bus bridge hub supporting other I/O interfaces, other embodiments may include MCH 172 integrated in I/O hub 190 and graphics interface 192 integrated in processor 170 . In at least one embodiment that includes integrated MCH 172 and graphics interface 192 in processor 170 , I/O hub 190 and bus bridge hub 118 may be integrated into a single-piece chipset 189 .
[0024] In some embodiments, persistent storage 128 includes code 129 executable by processor 170 to perform operations. In at least one embodiment, code 129 includes code for an OS 127 . In at least one embodiment, OS 127 includes a core performance scalability algorithm 142 and an uncore performance scalability algorithm 144 to determine or estimate a performance scalability of processor 170 . In some embodiments, OS 127 also includes core power scalability algorithm 146 and uncore power scalability algorithm 148 to determine or estimate a power scalability of processor 170 .
[0025] In at least one embodiment, OS 127 also includes a sensor API 150 , which provides application program access to one or more sensors 112 . In at least one embodiment, sensors 112 include, but are not limited to, an accelerometer, a global positioning system (GPS) device, a gyrometer, an inclinometer, and an ambient light sensor. In some embodiments, OS 127 also includes a resume module 154 to reduce latency when transitioning system 100 from a power conservation state to an operating state. In at least one embodiment, resume module 154 may work in conjunction with NV RAM 140 to reduce the amount of storage required when system 100 enters a power conservation mode. Resume module 154 may, in one embodiment, flush standby and temporary memory pages before transitioning to a sleep mode. In some embodiments, by reducing the amount of system memory space that system 100 is required to preserve upon entering a low power state, resume module 154 beneficially reduces the amount of time required to perform the transition from the low power state to an operating state.
[0026] In at least one embodiment, OS 127 also includes a connect module 152 to perform complementary functions for conserving power while reducing the amount of latency or delay associated with traditional “wake up” sequences. In some embodiments, connect module 152 may periodically update certain “dynamic” applications including, email and social network applications, so that, when system 100 wakes from a low power mode, the applications that are often most likely to require refreshing are up to date.
[0027] FIG. 2A illustrates a processor used in conjunction with at least one embodiment. In at least one embodiment, processor 170 includes a core region 178 and an uncore region 180 . In some embodiments, core region 178 includes processing cores 174 - 1 and 174 - 2 . Other embodiments of processor 170 may include more or fewer processing cores 174 .
[0028] In some embodiments, each processing core 174 includes a core or level 1 (L1) instruction cache 203 , a front-end 204 , execution pipes 206 , a core or L1 data cache 208 , and an intermediate or level 2 (L2) cache 209 . In at least one embodiment, front-end 204 receives or generates program flow information including an instruction pointer and branch predictions, fetches or prefetches instructions from core instruction cache 203 based on the program flow information it receives, and issues instructions to execution pipes 206 . In some embodiments, front-end 204 may also perform instruction decoding to identify operation codes, identify source and destination registers, and identify any memory references. In at least one embodiment, execution pipes 206 may include multiple parallel execution pipelines including one or more floating point pipelines, one or more integer arithmetic logic unit pipelines, one or more branch pipelines, and one or more memory access pipelines, also referred to herein as load/store pipelines. In some embodiments, execution pipes 206 may generate micro code to process the instructions from core instruction cache 203 , route instructions through the appropriate execution pipeline, and store any results in destination registers. In some embodiments, execution pipes 206 may encompass a register file that may support features including register renaming, speculative execution, and out-of-order execution of instructions.
[0029] In at least one embodiment, uncore region 180 includes a last level (L3) cache (LLC) 275 and cache control logic 222 . In this embodiment, LLC 275 is a shared resource for all of processing cores 174 of processor 170 . In some embodiments, as suggested by its name, LLC 275 represents, from the perspective of processor 170 , the last available hierarchical tier of cache memory. In at least one embodiment, if a memory access instruction that is presented to LLC 275 generates a cache miss, the requested data must be retrieved from system memory 120 .
[0030] In some embodiments, processing core 174 and/or uncore region 180 may include one or more levels of a cache hierarchy between core caches 203 , 208 , intermediate cache 209 , and LLC 275 . In some embodiments, each of the cache memories of processing core 174 may have a unique architectural configuration. In at least one embodiment, core data cache 208 , intermediate cache 209 and LLC 275 are multiple-way, set associative caches. In some embodiments, LLC 275 is inclusive with respect to intermediate cache 209 while, in other embodiments, LLC 275 may be exclusive or non-inclusive with respect to intermediate cache 209 . Similarly, in some embodiments, intermediate cache 209 may be either inclusive or non-inclusive with respect to core data cache 208 , core instruction cache 203 , or both.
[0031] In at least one embodiment, cache control logic 222 controls access to the cache memories, enforces a coherency policy, implements a replacement policy, and monitors memory access requests from external agents, including but not limited to, other processors 170 or I/O devices. In at least one embodiment, LLC 275 , intermediate cache 209 , and core caches 203 , 208 comply with the MESI protocol or a modified MESI protocol. The four states of the MESI protocol are described in Table 1.
[0000]
TABLE 1
Description of Cacheline States in the MESI Protocol
MESI State
Description
Modified
The cache line contains valid data that is modified from the system
memory copy of the data. Also referred to as a ‘dirty’ line.
Exclusive
The line contains valid data that is the same as the system memory copy
of the data. Also indicates that no other cache has a line allocated to this
same system memory address. Also referred to as a ‘clean’ line.
Shared
The line contains valid and clean data, but one or more other caches have
a line allocated to this same system memory address.
Invalid
The line is not currently allocated and is available for storing a new entry.
[0032] In some embodiments, the cache memories of processor 170 may implement a modified MESI protocol, which might include, in one embodiment, an “F” state identifying one of a plurality of “S” state lines, where the “F” state line is designated as the line to forward the applicable data should an additional request for the data be received from a processor that does not have the data.
[0033] In at least one embodiment, uncore region 180 of processor 170 also includes power control unit 230 to control power provided to the various resources of processor 170 . In some embodiments, power control unit 230 provides unique power supply levels to core region 178 and uncore region 180 . In other embodiments, power control unit 230 may be further operable to provide unique power supply levels to each processing core 174 and/or provide clock signals at unique frequencies to processing cores 174 . In addition, in some embodiments, power management unit 230 may implement various power states for processor 170 and define or respond to events that produce power state transitions.
[0034] In some embodiments, uncore region 180 includes graphics adapter 291 to support low latency, high bandwidth communication with a display device (not depicted). In some embodiments, the integration of graphics adapter 291 into processor 170 represents an alternative embodiment, in which graphics interface 192 is implemented in the I/O hub 190 .
[0035] In at least one embodiment, uncore region 180 includes a bus interface unit 226 to support communication with one or more chipset devices, discreet bus interfaces, and/or individual I/O devices. In some embodiments, bus interface unit 226 provides one or more point-to-point interfaces such as the interfaces 176 and 173 . In other embodiments, bus interface unit 226 may provide an interface to a shared bus to which one or more other processors 170 may also connect.
[0036] FIG. 2B illustrates an out-of-order execution core. In one embodiment, execution core 205 includes all or some of the elements of front end 204 and execution engine 206 of processing core 174 . In at least one embodiment, pending loads may be speculatively issued to a memory address before other older pending store operations according to a prediction algorithm, such as a hashing function. In at least one embodiment, execution core 205 includes a fetch/prefetch unit 251 , a decoder unit 253 , one or more rename units 255 to assign registers to appropriate instructions or micro-ops, and one or more scheduling/reservation station units 260 to store micro-ops corresponding to load and store operations (e.g., STA micro-ops) until their corresponding target addresses source operands are determined. In some embodiments an address generation unit 262 to generate the target linear addresses corresponding to the load and stores, and an execution unit 265 to generate a pointer to the next operation to be dispatched from the scheduler/reservation stations 260 based on load data returned by dispatching load operations to memory/cache are also included. In at least one embodiment, a memory order buffer (MOB) 263 , which may contain load and store buffers to store loads and stores in program order and to check for dependencies/conflicts between the loads and stores is included. In one embodiment, loads may be issued to memory/cache before older stores are issued to memory/cache without waiting to determine whether the loads are dependent upon or otherwise conflict with older pending stores. In other embodiments, processor 170 is an in-order processor.
[0037] Referring now to FIG. 3 , an illustration of an embodiment of a cache control logic is illustrated. In at least one embodiment, cache control logic 222 is used to determine if a memory request is cacheable. In some embodiments, cache control logic 222 includes cache replacement policy 223 and a replacement policy selector (RPS) 302 . In some embodiments, cache replacement policy 223 includes three different replacement policies: normal replacement policy 312 , aggressive replacement policy 314 and less aggressive replacement policy 316 . In some embodiments, aggressive replacement policy 314 enforces evictions to remove dirty lines in the cache for write and read misses while less aggressive replacement policy 316 enforces evictions to only remove dirty lines in the cache for write misses. In some embodiments, RPS 302 is checked for bits that are set to select the replacement policy and the selection 304 is sent to the cache replacement policy block 223 . In at least ones embodiment, block 330 represents a key to a MESI protocol.
[0038] In at least ones embodiment, multiplexor 336 selects a signal based on the output of R/W selector block 334 , where a selection is made of a read or write miss based on read/write signal 332 , and on the cache replacement policy selection 223 made by RPS 302 . In some embodiments, the selected signal from 336 is sent to multiplexor 338 where a signal selection is made based on the cache replacement policy selection 223 made by RPS 302 . In some embodiments, the selected signal from 338 is sent to multiplexor 354 . When a replacement occurs, the MESI protocol ( 352 - 1 , 352 - 2 , 352 - 3 , 352 - 4 ) and two additional bits ( 353 - 1 , 353 - 2 , 353 - 3 , 353 - 4 ) are, in some embodiments, checked in blocks 350 - 1 , 350 - 2 , 350 - 3 and 3 - 354 . In some embodiments, respective signals from 350 - 1 , 350 - 2 , 350 - 3 and 350 - 4 are sent to multiplexors 354 , 355 , 356 and 357 . In some embodiments, the multiplexors based on the input signals selects a signal to be sent to 358 - 1 , 358 - 2 , 358 - 3 and 358 - 4 respectively and stores the information in bits 359 - 1 , 359 - 2 , 359 - 3 and 359 - 4 respectively.
[0039] In some embodiments, the way-select values are chosen in the following manner by the cache control logic 222 . Way-select 340 uses comparator 342 to compare the values of 358 - 1 and 358 - 2 to select the larger value to send to comparator 346 and to multiplexor 348 . While comparator 344 compares the values of 358 - 3 and 358 - 4 to select the larger value to send to comparator 346 and multiplexor 348 . Comparator 346 compares the values from comparator 342 and 344 to select the larger value to result in a way value 362 , while multiplexor 348 uses the outputs of comparator 342 and 344 and selects based on the way value output of comparator 346 a select value 364 .
[0040] Referring now to FIG. 4 , one embodiment of a method of modifying an algorithm in order to reduce a DUE FIT rate is illustrated. In some embodiments, method 400 begins with estimating a DUE FIT rate in block 402 . In some embodiments, the estimated DUE FIT rate is tracked (block 404 ) and then a determination is made if the estimated DUE FIT rate exceeds a target DUE FIT rate in decision block 406 . In some embodiments, if the estimated DUE FIT rate does not exceed the target DUE FIT rate, then the flow resumes tracking of the estimated DUE FIT rate (block 404 ). In some embodiments, if the estimated DUE FIT rate does exceed the target DUE FIT rate, a determination must be made in decision block 408 if the estimated DUE FIT rate exceeds a DUE FIT rate threshold. In some embodiments, if the estimated DUE FIT rate exceeds the DUE FIT rate threshold, an aggressive replacement policy is set (block 410 ) and evictions are enforced to remove dirty lines in a cache for write and read misses (block 412 ). In some embodiments, if the estimated DUE FIT rate does not exceed the DUE FIT rate threshold in block 408 , a less aggressive replacement policy is set (block 414 ) and evictions are enforced to only remove dirty lines in a cache for write misses (block 416 ).
[0041] Referring now to FIG. 5 , one embodiment of a method of modifying an algorithm at core level to guarantee a DUE FIT rate is illustrated. In at least one embodiment, method 500 emphasizes per core determinations of DUE FIT rate and maintaining per core eviction policies that are influenced by DUE FIT rates so that one core may be enforcing an aggressive eviction policy to reduce the number of modified lines while another core may be operating under a relaxed policy. In some embodiments, method 500 begins with estimating a DUE FIT rate in block 502 . In some embodiments, the estimated DUE FIT rate is tracked (block 504 ) and then a determination is made if the estimated DUE FIT rate exceeds a target DUE FIT rate in decision block 506 . In some embodiments, if the estimated DUE FIT rate does not exceed the target DUE FIT rate, then the flow resumes tracking of the estimated DUE FIT rate (block 504 ). In some embodiments, if the estimated DUE FIT rate does exceed the target DUE FIT rate, a replacement policy is selected for each core using the RPS (block 508 ). Based on the replacement policy selection for each core, in some embodiments, either a normal replacement policy is implemented (block 514 ), an aggressive replacement policy is set (block 510 ) enforcing evictions to remove dirty lines from write and read misses (block 512 ), or a less aggressive replacement policy is set (block 516 ) enforcing evictions to only remove dirty lines for write misses (block 518 ). It is possible for all cores to select the same replacement policy or have each core select different replacement policies based on the particular application.
[0042] Referring now to FIG. 6 , a representation for simulation, emulation and fabrication of a design implementing the disclosed techniques is illustrated. Data representing a design may represent the design in a number of manners. First, as is useful in simulations, the hardware may be represented using a hardware description language or another functional description language which basically provides a computerized model of how the designed hardware is expected to perform. In at least one embodiment, the hardware model 614 may be stored in a storage medium 610 such as a computer memory so that the model may be simulated using simulation software 612 that applies a particular test suite to the hardware model 614 to determine if it indeed functions as intended. In some embodiments, the simulation software 612 is not recorded, captured or contained in the medium.
[0043] Additionally, a circuit level model with logic and/or transistor gates may be produced at some stages of the design process. This model may be similarly simulated, sometimes by dedicated hardware simulators that form the model using programmable logic. This type of simulation, taken a degree further, may be an emulation technique. In any case, re-configurable hardware is another embodiment that may involve a tangible machine readable medium storing a model employing the disclosed techniques.
[0044] Furthermore, most designs, at some stage, reach a level of data representing the physical placement of various devices in the hardware model. In the case where conventional semiconductor fabrication techniques are used, the data representing the hardware model may be the data specifying the presence or absence of various features on different mask layers for masks used to produce the integrated circuit. Again, this data representing the integrated circuit embodies the techniques disclosed in that the circuitry or logic in the data can be simulated or fabricated to perform these techniques.
[0045] In any representation of the design, the data may be stored in any form of a tangible machine readable medium. In some embodiments, an optical or electrical wave 640 modulated or otherwise generated to transmit such information, a memory 630 , or a magnetic or optical storage 620 such as a disc may be the tangible machine readable medium. Any of these mediums may “carry” the design information. The term “carry” (e.g., a tangible machine readable medium carrying information) thus covers information stored on a storage device or information encoded or modulated into or on to a carrier wave. The set of bits describing the design or the particular part of the design are (when embodied in a machine readable medium such as a carrier or storage medium) an article that may be sold in and of itself or used by others for further design or fabrication.
[0046] The following pertain to further embodiments.
[0047] Embodiment 1 is a processor comprising: a core data cache; cache control logic to receive: a hit/miss from the core cache; a read/write signal from a load store unit; and an eviction policy signal indicative of a detectable unrecoverable error failure in time (DUE FIT) rate of the core data cache; age modification logic to: modify an age attribute of a modified cache line based on the read/write signal and the eviction policy signal.
[0048] In embodiment 2, the eviction policy signal included in the subject matter of embodiment 1 can optionally include an aggressive policy value, an intermediate policy value, and a relaxed policy value.
[0049] In embodiment 3, the age modification logic included in the subject matter of embodiment 1 can optionally increase the age attribute of all modified lines in the way responsive to assertion of the aggressive policy value.
[0050] In embodiment 4, the age modification logic included in the subject matter of embodiment 1 can optionally increase the age attribute of modified lines responsive to assertion of the intermediate policy value and the assertion of the write signal;
[0051] In embodiment 5, the subject matter of embodiment 1 can optionally include DUE FIT estimation logic to estimate the DUE FIT rate.
[0052] In embodiment 6, the DUE FIT estimation logic included in the subject matter of embodiment 5 can optionally estimate DUE FIT based on a number of modified lines in the core data cache.
[0053] In embodiment 7, the processor included in the subject matter of embodiment 1 can optionally include
[0054] multiple processing cores and wherein each core includes the cache control logic and the age modification logic to influence eviction policy based on an estimate of the DUE FIT rate for the core.
[0055] Embodiment 8 is a cache eviction method comprising: obtaining DUE FIT data indicative of a DUE FIT rate; comparing the DUE FIT rate to a first threshold; responsive to the DUE FIT rate exceeding the first threshold, evicting modified lines preferentially in response to all cache miss events.
[0056] In embodiment 9, the subject matter of embodiment 8 can optionally include responsive to the DUE FIT rate not exceeding the first threshold but exceeding a second threshold, evicting modified lines in response to write miss events and evicting based on a recency policy otherwise.
[0057] In embodiment 10, the subject matter of embodiment 8 can optionally include responsive to the DUE FIT rate not exceeding the second threshold, setting a relaxed eviction policy wherein lines are evicted based on a recency policy in response to cache miss events.
[0058] In embodiment 11 the subject matter of embodiment 8 can optionally include the processor including a plurality of cores and the method includes performing for each core: the obtaining of DUE FIT data indicative of a DUE FIT rate; the comparing of the DUE FIT rate to a first threshold; and responsive to the DUE FIT rate exceeding the first threshold, the evicting of modified lines preferentially in response to all cache miss events.
[0059] In embodiment 12, the subject matter of embodiment 8 can optionally include estimating the DUE FIT RATE based on an estimate of the number of modified lines.
[0060] Embodiment 13 is a computer system comprising: a processor comprising: a core data cache; cache control logic to receive: a hit/miss from the core cache; a read/write signal from a load store unit; and an eviction policy signal indicative of a detectable unrecoverable error failure in time (DUE FIT) rate of the core data cache; age modification logic to: modify an age attribute of a modified cache line based on the read/write signal and the eviction policy signal.
[0061] In embodiment 14, the subject matter of embodiment 13 can optionally include wherein the eviction policy signal includes an aggressive policy value, an intermediate policy value, and a relaxed policy value.
[0062] In embodiment 15, the subject matter of embodiment 13 can optionally include wherein the age modification logic increases the age attribute of all modified lines in the way responsive to assertion of the aggressive policy value.
[0063] In embodiment 16, the subject matter of embodiment 13 can optionally include wherein the age modification logic increases the age attribute of modified lines responsive to assertion of the intermediate policy value and the assertion of the write signal;
[0064] In embodiment 17, the subject matter of embodiment 13 can optionally include wherein further comprising DUE FIT estimation logic to estimate the DUE FIT rate.
[0065] In embodiment 18, the subject matter of embodiment 17 can optionally include wherein the DUE FIT estimation logic estimates DUE FIT based on a number of modified lines in the core data cache.
[0066] In embodiment 19, the subject matter of embodiment 13 can optionally include wherein the processor includes multiple processing cores and wherein each core includes the cache control logic and the age modification logic to influence eviction policy based on an estimate of the DUE FIT rate for the core.
[0067] In embodiment 20, the subject matter of any one of embodiments 1-6 can optionally include wherein the processor includes multiple processing cores and wherein each core includes the cache control logic and the age modification logic to influence eviction policy based on an estimate of the DUE FIT rate for the core.
[0068] In embodiment 21, the subject matter of any one of embodiments 8-11 can optionally include estimating the DUE FIT RATE based on an estimate of the number of modified lines.
[0069] In embodiment 22, the subject matter of any one of embodiments 13-18 can optionally include wherein the processor includes multiple processing cores and wherein each core includes the cache control logic and the age modification logic to influence eviction policy based on an estimate of the DUE FIT rate for the core.
[0070] To the maximum extent allowed by law, the scope of the present disclosure is to be determined by the broadest permissible interpretation of the following claims and their equivalents, and shall not be restricted or limited to the specific embodiments described in the foregoing detailed description. | A system, processor and method to reduce the overall detectable unrecoverable FIT rate of a cache by reducing the residency time of dirty lines in a cache. This is accomplished through selectively choosing different replacement policies during execution based on the DUE FIT target of the system. System performance and power is minimally affected while effectively reducing the DUE FIT rate. | 8 |
This non-provisional application claims priority based upon prior U.S. Provisional Patent Application Ser. No. 60/342,031 filed Dec. 18, 2001 in the names of Shawn Thomas, Gregory Gray, Michael Woodfin, Warner Mizell and Brian Thomas, entitled “Method and System for Deploying, Tracking and Managing Technology-Related Resources.”
BACKGROUND
Technical Field of the Invention
In most cases, a physical inventory is taken to determine what assets the company has in inventory and the current status of those assets. Typically, a computer technician would access the existing asset and make either handwritten notes of the user's setting and preferences or input the information into a computer and save it to a diskette. This process is expensive and time consuming and yields a static result in which the data becomes stale as soon as the asset returns to service.
Effective asset management using existing methods is further limited because the information that is collected is not collected in such a manner that it is can be compiled, managed and updated in the future. Under existing methods, once the computer technician re-installs the information on a new machine, he destroys any records that he may have kept relating, for example, to the specific versions of software installed, the serial number of the computer on which it was installed or the date of installation and, if the information is saved, it is usually not accessible in an organized, easily-accessible manner. Consequently, when the new machine is ready to be upgraded, relocated or decommissioned, the computer technician must start anew to gather information about it and the user's settings and preferences.
There is a need, therefore, for an improved method and system for integrated asset management.
SUMMARY
Various embodiments provide a method for asset management in which information concerning the asset and the user are aggregated from a variety of sources into a computerized centralized database. Thereafter, asset transition events are scheduled. Information from the centralized computerized database is used in the performance of the asset transition events and information relating to the asset transition events is added to the centralized computerized database. Subsequent changes to the asset are also recorded into the centralized computerized database. As a result, a plethora of information is available within said database for the purpose of managing future asset transition events.
BRIEF DESCRIPTION OF THE DRAWINGS
The disclosed invention will be described with reference to the accompanying drawings, which show important sample embodiments of the invention and which are incorporated in the specification hereof by reference, wherein:
FIG. 1 is a flow diagram of a typical asset management workflow process;
FIG. 2 is a workflow diagram showing the preferred method for asset management according to the present invention;
FIG. 3 is a screen display showing user information aggregated during the method for integrated asset management;
FIG. 4 is a screen display showing current asset information aggregated during the method for integrated asset management;
FIG. 5 is a screen display showing new asset information aggregated during the method for integrated asset management;
FIG. 6 is a screen display showing software application information aggregated during the method for integrated asset management;
FIG. 7 is a workflow diagram showing the application management process;
FIG. 8 is a screen display showing system inventory information collected during the application management process;
FIG. 9 is a screen display showing the application dictionary; and
FIG. 10 is a screen display showing user software information collected during the application management process.
FIG. 11 is a system for integrated asset management.
DETAILED DESCRIPTION
The numerous innovative teachings of the present application will be described with particular reference to the present embodiments. However, it should be understood that these embodiments provide only a few examples of the many advantageous uses of the innovative teachings herein. In general, statements made in the specification of the present application do not necessarily delimit any of the various claimed inventions. Moreover, some statements may apply to some inventive features, but not to others.
FIG. 1 illustrates a typical asset management workflow. The initial step is to aggregate information 120 . Information can be derived from a number of different sources. For example, information necessary in the asset transition may include ownership information 101 , usage information 102 , user information 103 , legacy asset information 104 , new asset information 105 , software application information 106 , financial information 107 , site information 108 , event history information 109 , and logistical information 110 . The initial assessment of available data sources dictates the process that will be used to acquire this information. In general, it may be desirable to utilize existing data sources provided by the user. Because of the volume of information required, it is often difficult to obtain thorough information regarding the assets in question. In such cases, it may be necessary to proceed with an asset transition without all available information or to delay the asset transition until such time as the information is available.
Once information regarding the assets in question has been aggregated, a company will typically schedule an asset transition 130 , such as an asset installation, asset relocation, asset disposition or asset maintenance activity. The scheduling activity is typically conducted on an ad hoc user by user basis, with little thought given to sequencing the asset transition services occurring between individual users and between individual assets. This results in a costly and inefficient asset transition.
The next step is to perform the asset transition 140 . Even though great effort may have been expended in order to aggregate the information, little effort is typically made to retain, manage, or update that information for future use. Generally, records may be kept of the asset transition activities, but no effort is made to keep the information current on an ongoing basis.
A method for integrated asset management according to one embodiment is shown in FIG. 2 . The first step is to aggregate information 220 . Once again, the type of information aggregated includes ownership information 201 , usage information 202 , user information 203 , legacy asset information 204 , new asset information 205 , software application information 206 , financial information 207 , site information 208 , event history information 209 , and logistical information 210 . Once aggregated, the information is stored, for example, in a relational database.
Under this embodiment, it may be desirable to obtain accurate information in each of the foregoing instances. When accurate, up-to-date information is available, that information may be included within the information that is aggregated. If accurate and up-to-date information is not available, it may be necessary to match multiple data sources and utilize discovery technology to build an accurate information repository. Although additional time is required to gather information anew, it may be desirable to have accurate and complete information in the repository. This information can be acquired in a number of ways. For example, the typical sources for user information are either the human resource system or e-mail. Typical sources for legacy asset information include fixed asset schedules and legacy asset management systems. Software application information may be found through an electronic discovery process and site information can be derived from the human resource system, fixed asset system, facilities information, IP address schemes, or internal address books.
It is instructive to examine the type of information aggregated as part of this embodiment. For example, user information 203 provides details about each end user who will be involved from a service delivery standpoint. Such information includes the user's name, contact phone numbers, mail addresses, e-mail addresses and organizational information, such as manager, department and cost center. User information 203 may also include information regarding the user's role in the organization, if they have the IP status and if they are a remote user.
Legacy asset information 204 includes such information as configuration, serial numbers, manufacturer, make, model, internal components, and attached devices. This information is typically gathered through use of an electronic discovery technology. Other legacy asset information 204 includes details about the physical location of an asset within a building, cube number, office number, jack number and IP address.
New asset information 205 is the information used for procurement or order placement. The details for each new asset are derived from an integrated configuration catalogue. The catalogue contains the basic system information as well as details about specific configuration options for each new asset. This information is then sent to the manufacturers to acquire the appropriate new assets for the technology implementation. New asset information may include such information as scheduled install date, new workstation type, workstation description, workstation costs, and attached devices. For application information 206 identifies which software applications are being used by, or are resident on, a given asset. For application information 206 can be obtained by scanning the shortcuts or an in-depth scan of all executable files on the computer. The results of the scan are then filtered against an application dictionary. The application dictionary contains a profile of each application in it, its current status, ownership and readiness for deployment. The application filtering process yields a definitive list of the applications that need to be installed on the new device. A detailed description of the preferred embodiment for collection of software application information is described later.
Site information 208 includes information about each individual site where a service will be performed. Site information 208 includes basic information, such as address and type of site, as well as detailed information about the logistics of the site, such as network infrastructure, special considerations regarding accessing the site, and contact resources.
The foregoing examples are intended to illustrate the types of information to be collected as part of the initial step of aggregating information 220 . The information is stored on a storage medium distinct from the asset in question. Information may be stored on the remote storage medium in a centralized computerized database. Information may be transmitted to this centralized computerized database, for example, through the Internet or through a local area network. Also, it may be desirable to transmit such information by means of a secure, encrypted transmission. Alternatively, it may be desirable to change the file into formatted data files prior to transmission or to incorporate a means for removing unwanted or redundant information prior to transmission.
After all information has been aggregated, the next step is to schedule the asset transition 230 . Assets involved in the asset transition may be, for example, desktop computers, laptop computers, handheld computers, printers, scanners, networking devices and storage devices. In the preferred embodiment, users are grouped together by site and proximity that will be the makeup of a scheduled implementation. Scheduling is facilitated through a series of automated processes that reconcile the activities of software, labor and equipment components necessary for the asset transition. As the transition activities are scheduled, a series of readiness checks are performed to ensure that the new assets and applications are ready for deployment. If certain assets or applications are not ready, the schedule is instantaneously modified in order to minimize activity disruptions during the asset transition process.
The next step is to perform the asset transition 240 . Depending upon the specific transition to be performed, a tailored web page or series of web pages to guide the technician through the process. The use of automated functions simplifies and streamlines the transition process. Examples of the types of automated processes used to perform asset transition 240 include a central repository of the aggregated information, an auto discovery agent that detects all relevant aspects of a networked device and its resident applications, an automated application to backup and restore user data from an old device to a new device, an automated application to backup and restore personality settings from an old device to a new device, an automated application to detect an asset's serial number, an application dictionary as previously described, and an automated application that invokes the downloading of a user's application from a remote database. These integrated technologies are inherent in the preferred embodiment and are critical to support an efficient workflow process, maintain an up-to-date central repository, reduce technician time, reduce technician error, capture and track the results of a technician's work as he performs tasks and make accurate information available to interested parties.
The specific process performed by the technician as he performs asset transition 240 may have multiple steps. Use of the web page system allows the ability to capture information about each step such as time, number of units installed and increments. This information is used for ongoing asset management. For example, the information captured during the process notify the actual minutes required to perform a task, the actual number of data files and sizes backed up and restored, and the duration of time involved.
The next step is to engage in continuously monitoring asset events 250 . This step is critical to maintain a vibrant and robust repository of information. As new asset transition events occur, information from those events must be added to the information repository in order to keep the most current information available to interested parties.
The final step in the process is the management of asset inventory 260 . As the information repository contains accurate, up-to-date information regarding the assets, those assets can be managed in on a real-time basis. Assets may be managed at a very high level, for example, in an executive summary, down to a detailed task level. Information available to assist in asset management may include, for example, status by location, status by group, hardware mix by site, user detailed software reports, warehouse status by group, technical status, asset reconciliation, asset disposition and user survey satisfaction. Management may include project management, installation management, relocation management, lease management, exception management, scheduling management, workflow management and resource management. In addition reports may be generated based on the aforementioned management activities, including such reports as project reports, asset reports, lease reports, activity reports, exception reports and consumer satisfaction reports. As part of the overall management function, a means may also be provided for monitoring, updating and controlling versions of the software installed on different devices or a means for translating information in the centralized computerized database into a common language.
FIG. 3 illustrates a screen display in which the technician is prompted to impute user information. User information will provide detail about each end user who will be involved in the process. User information includes new names, contact phone numbers, e-mail addresses and organizational information, such as the manager's name, user's department and cost center. Other user information may include the user's role in the organization, whether or not the user has VIP status and whether or not they use the system remotely.
FIG. 4 illustrates a screen display which the technician may use to impute Legacy Asset information. This may include such information as the configuration, serial numbers, manufacturer, make, model, internal components and attached devices. Other Legacy Asset information may include details regarding the physical location of the asset within a building, office number, cube number, jack number and IP address.
FIG. 5 illustrates screen display which a technician may use to impute new asset information. Such information is primarily used for the procurement of the new asset. Details for each new asset are generally derived from integrated configuration catalog. Such catalog contains basic information, as well as specific details, regarding specific configuration options for each asset. Such information is then forwarded to the selected manufacturer acquisition.
FIG. 6 illustrates a screen display which a technician may use to impute software application information. Such information may include the name of the application, the status of the application, whether the application has been registered or not, whether the license for the application is an enterprise license, the order in which the application should be installed, and the version of the application.
FIG. 7 illustrates a work flow diagram showing the application management process. Initially, an electronic auto discovery tool identifies applications on the desktop. The equipment is scanned to identify the application used, information such as the names of executable files, manufacturer, version and path are captured, and the auto discovery results 701 are sent to the data dictionary 700 in the form of an XML package. The auto discovery results 701 are then processed against the data dictionary 700 . The data dictionary 700 was created from electronic auto discovery processes with previous updates of non-discovered information. The data dictionary 700 therefor contains details about all available applications. Such as, for example, the status, the media on which it was installed, and authorized installers. The auto discovery results 701 are processed against the data dictionary 700 in order to control the discovery process, rationalize the results, control the installation process and control the quality of the installation.
A user software page 702 is then created based on the information in the data dictionary 700 . During the creation of the user software page 702 , the system will analyze the software page 703 against the information contained in the data dictionary 700 . During this analysis, an assessment will be made of whether the applications discovered or selected are contained within the data dictionary and whether the applications are available in the image. The analysis will determine the difference between the applications on the user's software page 702 and those in the data dictionary 700 . A report can then be generated of the differences. In addition, a mechanism can be incorporated to define an import missing applications into the dictionary. Once the user's software pages 702 have been established, the next step is to update the software status 704 . Each software application can be classified as just for example “discovered” in which it doesn't appear in the technician's installation or quality control pages, “install” in which it appears on technicians and quality control pages, “do not install” in which it doesn't appear in technician or quality control pages or “install later” in which it doesn't appear in technician or quality control pages. In addition, non-packaged applications can be identified and installed or marked for later installation. Once the software status has been updated, 704 , those software applications designated for installation will be installed 706 . Thereafter, there will be a quality control function performed on the software 707 . During this step, the applications are quality controlled against the intended list.
FIG. 8 illustrates a screen display showing system inventory information which may be generated from the Auto Discovery results. System inventory information contains such information as the names of executable files, the manufacturer of the product, the internal name of the product and the path. This information is subsequently forwarded to the data dictionary.
FIG. 9 illustrates the information contained in the data dictionary. The data dictionary contains information from the auto discovery results such as the software applications discovered and the applications available in the image.
FIG. 10 illustrates a screen display showing user software information. User software information includes such information as the name of the software application, where the application was installed and the status of the application.
FIG. 11 illustrates the preferred embodiment for a system for integrated asset management. In this system, assets 1101 , 1102 and 1103 connected to a centralized, computerized data base 1100 . The system provides a means, 1111 , 1112 and 1113 for aggregating information from the assets, 1101 , 1102 and 1103 into the centralized, computerized data base 1100 .
Once information has been received from the assets 1101 , 1102 and 1103 , asset transition events can be scheduled information relating to those asset transition events can be stored in the centralized, computerized data base 1100 . Thereafter, the assets 1101 , 1102 and 1103 can be tracked on an on-going basis so that information regarding future activities effecting the assets are recorded in the centralized, computerized data base 1100 . Accordingly, future asset transition events can be scheduled using information contained in the centralized, computerized data base 1100 .
It should be noted that the centralized, computerized data base 1100 may reside in a remote location separate from the assets. Information may be stored in the centralized, computerized data base 1100 in a relational data base. Information may be transmitted from the assets 1101 , 1102 and 1103 through the centralized, computerized data base 1100 through, for example, the Internet or a local area network. Moreover, it may be desirable to make such transmissions in a secure, encrypted manner.
The assets in the system may, for example, be desktop computers, laptop computers, hand-held computers, printers, scanners, networking devices or storage devices. Information transmitted between the assets 1101 , 1102 and 1103 through the centralized, computerized data base may include such information as user information, legacy asset information, new asset information, software application information, financial information, site information, event history information, logistical information, ownership information and usage information.
The previously described asset transition events may include such events as asset installation, asset relocation, asset disposition and asset maintenance. When information is conveyed from the assets 1101 , 1102 and 1103 to the centralized, computerized data base 1100 the information may be first converted to a formatted data file for ease of storage and transmission and transfer. In addition, certain information may be filtered prior to transmission in order to remove unwanted or redundant information.
Information has been incorporated into the centralized, computerized data base and the assets 1101 , 1102 and 1103 , are being monitored, it may be desirable to manage activities of the assets. Management activities may include project management, installation management, relocation management, lease management, exception management, scheduling management, work flow management and resource management. In addition, it may be desirable to generate reports from the information contained in the centralized, computerized data base 1100 . These reports may include project reports, asset reports, lease reports, activity reports, exception reports and consumer satisfaction reports. It may also be desirable to use the foregoing system to monitor, update and control versions of software resident on the assets 1101 , 1102 and 1103 . The system can also accommodate the translation of information in the centralized, computerized data base 1100 to a standard language. | The method and system of the present invention provides an improved technique for integrated asset management. Information is aggregated from a variety of sources into a centralized computerized database. Thereafter, asset transition events are scheduled. Information from the centralized computerized database is used in the performance of the asset transition events and information relating to the asset transition events is added to the centralized computerized database. Subsequent changes to the asset are also recorded into the centralized computerized database. As a result, a plethora of information is available within said database for the purpose of managing future asset transition events. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to polyamide molding compounds.
2. Description of the Background
Molding compounds based on aromatic polyamides which have the basic structure: ##STR2## are generally known (Ger. OS 36 09 011). Also known are polyamide molding compounds which have an amorphous structure (Eur. Pat. 0,053,876, Eur. OS 0,271,308; and Ger. OS 36 00 015). These amorphous molding compounds in particular have unsatisfactory heat resistance and unsatisfactory endurance temperature. A need therefore continues to exist for aromatic polyamides which provide for molding compounds of improved properties.
SUMMARY OF THE INVENTION
Accordingly, one object of the present invention is to provide a molding polyamide compound which exhibits improved thermal properties.
Briefly, this object and other objects of the present invention are hereinafter will become more readily apparent can be attained in a molding compound which comprises (I) an aromatic polyamide having the formula: ##STR3## where ##STR4## designates an aromatic dicarboxylic acid, n is a number between 5 and 500; X represents --SO 2 -- or --CO--, and
Y represents --O-- or --S--; and (II) an amorphous polyamide.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The preferred molding compounds of the present invention have a ratio b weight of component I to component II in the range 99:1 to 1:99, preferably in the range 90:10 to 10:90. The polyamides (component I) are prepared from aromatic dicarboxylic acids which include isophthalic acid, terephthalic acid, 1,4-, 1,5-, 2,6- and 2,7-naphthalenedicarboxylic acid, 4,4'-diphenyl ether dicarboxylic acid, 4,4'-benzophenonedicarboxylic acid, 4,4'-diphenylsulfone dicarboxylic acid, 2-phenoxyterephthalic acid, 4,4'-biphenyldicarboxylic acid and mixtures thereof. Preferred is isophthalic acid alone or a mixture of isophthalic acid and another of the above-mentioned acids. In the case of a mixture, up to 45 mol % of the isophthalic acid is replaced by the other acid.
Suitable examples of aromatic diamines include 4,4'-bis(4-amino-phenoxy)diphenylsulfone, 4,4'-bis(3-aminophenoxy)diphenylsulfone, 4,4'-bis(4-aminophenoxy)benzophenone, 4,4'-bis(3-aminophenoxy)benzophenone, 4,4'-bis(p-aminophenylmercapto)benzophenone, 4,4'-bis(p-aminophenylmercapto)diphenylsulfone, and mixtures thereof. Preferred is 4,4'-bis(4-aminophenoxy)diphenylsulfone.
The molar ratio of dicarboxylic acid to diamine employed is in the range of c. 0.9:1 to 1:0.9.
In order to achieve improved hydrolysis resistance of the aromatic polyamide (component I), an additional 0.01-10 mol %, based on the sum of the dicarboxylic acid and the diamine, of a low molecular weight aliphatic, araliphatic, or aromatic carboxylic acid amide may be added to the compound. The aromatic group here may contain halogen substituents or C 1 -C 4 alkyl group substituents. These measures are described in Ger. OS 38 04 401.
The hydrolysis resistance of the compound can also be improved by employing the dicarboxylic acid in slight excess (Ger. OS 39 35 467), or, with the dicarboxylic acid and diamine present in approximately equimolar amounts, by further adding a monocarboxylic acid (Ger. OS 39 35 468) to the reacting ingredients.
The basic method of manufacturing aromatic polyamides is known. It is described, among other places, in Ger. OS 36 09 011.
Preferably a phosphorus-containing catalyst is employed in the manufacture of the aromatic polyamides. Suitable catalysts include, particularly, acids of the formula: H 3 PO 4 , where a=2 to 4, or derivatives of such acids. Examples include, in particular, phosphoric acid, phosphorous acid, hypophosphorous acid, phosphonic acids such as methanephosphonic acid and phenylphosphonic acid, phosphonous acids such as benzenephosphonous acid, and phosphinic acids such as di-phenylphosphinic acid. Salts of the acids may be used instead of the pure acids. Suitable cations include alkali metal ions, alkaline earth metal ions, zinc ions, and the like.
The catalyst is employed in the amount of 0.01-4.0 mol %, preferably 0.2-2.0 mol %, based on the sum of the dicarboxylic acid and the diamine.
A preferred method for manufacturing the aromatic polyamides is to employ dialkylaminopyridines as co-catalysts along with the catalyst. Particularly suitable dialkylaminopyridines include those with 1-10 C atoms in the alkyl group such as, preferably, 4-dimethylaminopyridine, 4-dibutylaminopyridine, and 4-piperidinylpyridine, with the possibility that a pyrrolidine or piperidine ring can be formed with the amine nitrogen of the pyridine compound.
If a co-catalyst is employed, the amount used is 0.05-4 mol %, preferably 0.2-2 mol %, based on the sum of the dicarboxylic acid and the diamine. Particularly preferred is the use of a co-catalyst in an amount equivalent to that of the catalyst in the reaction mixture.
The reaction is carried out in the melt at temperatures in the range 200°-400° C., preferably 230°-360° C.
Ordinarily, an inert gas atmosphere is used, with normal pressure. Less than atmospheric to superatmospheric pressures may be used, however. To increase the molecular weight, the aromatic polyamides can be subjected to a solid phase post-condensation, also in an inert gas atmosphere.
The glass temperature (Tg) of the aromatic polyamides is in the range 190°-270° C. Viscosity index (J-value) is about 30-250 cc/g, preferably 60-120 cc/g.
The amorphous polyamides (component II) are basically known (Elias, H. G., 1975, "Neue Polymere Werkstoffe", pub. C. Hansser Verlag, Munich/Vienna).
Suitable examples of amorphous polyamides are those produced either from a diamine and a dicarboxylic acid or from α,Ω-aminocarboxylic acids and their corresponding lactams. These polyamides are amorphous if they have no measurable distance-ordering in the absence of component I (Elias, H. G., "Makromolekuele", 5th Ed., pub. Verlag Huethig und Wept, pp. 725-729).
Suitable diamine reactants include those of 2-15 C atoms in the carbon skeleton such as 1,4-butanediamine, 1,6-hexanediamine, 1,8-octanediamine, 1,10-decanediamine, 1,12-dodecanediamine, trimethyl-1,6-hexanediamine, bis(4-aminocyclohcxyl)methane, bis(4-amino-3-methylcyclohexyl)methane, isophoronediamine, and the like. Mixtures of diamines may also be used.
The dicarboxylic acids have 4-40 C atoms in their carbon skeletons and include, e.g., succinic acid, adipic acid, suberic acid, sebacic acid, undecanedicarboxylic acid, dodecanedicarboxylic acid, cyclohexanedicarboxylic acid, terephthalic acid, isophthalic acid, and the like. Mixtures of dicarboxylic acids may also be used.
Suitable compounds for use as α,Ω-aminocarboxylic acids and their lactams are those with 5-14 C atoms in their carbon skeletons, e.g., caprolactam, laurolactam, and the like.
Examples of preferred polyamides are those comprised of units of:
terephthalic acid and trimethyl-1,6-hexanediamine, in which the terephthalic acid may be substituted to the extent of up to 40 mol % with other dicarboxylic acids, and the trimethyl-1,6-hexanediamine may be substituted to the extent of up to 60 mol % with other aliphatic diamines;
isophthalic acid and 1,6-hexanediamine, in which the 1,6-hexanediamine may be substituted to the extent of up to 40 mol % with other aliphatic diamines; and
isophthalic acid, bis(4-amino-3-methylcyclohexyl) methane, and laurolactam, in which the dicarboxylic acid and the diamine are used in approximately equimolar amounts, and the proportion of the laurolactam is 25-45 mol %, based on the entire mixture.
The method of manufacturing the amorphous polyamides is known, e.g., from Eur. OSs 0,053,876 and 0,271,308; Ger. OS 36 00 015; and 1985 Polymer News, 11, 40 ff.
The amorphous polyamides employed in the present molding compounds have a glass transition temperature (Tg) in the range 70°-220° C., preferably 30°-170° C., and viscosity indices (J-values) in the range 30-300 cc/g, preferably 60-200 cc/g.
Components I and II may be intermixed in conventional apparatus, by injection molding or extrusion, and may be processed in conventional apparatus to form molding compounds.
The molding compounds may also contain fillers such as talc or reinforcing materials such as fibers of glass, Aramid®, or carbon, as well as other customary additives, such as, e.g., pigments and stabilizers.
The present molding compounds are processed to produce molded parts, fibers, sheets, films and the like, by the usual processes such as injection molding, extrusion, and the like. It is also possible to use the materials as coatings based on a powder, e.g., by whirl sintering techniques or a liquid dispersion, or a solution.
It has been found that the present molding compounds have clearly better hot-forming stability and endurance temperatures than molding compounds comprised solely of aromatic polyamides.
Having generally described this invention, a further understanding can be obtained by reference to certain specific examples which are provided herein for purposes of illustration only and are not intended to be limiting unless otherwise specified.
The parameters referred to in the following Examples and elsewhere herein were determined by the following methods:
The glass point (Tg) and melting point (Tm) were determined with a DSC (differential scanning calorimeter) (Mettler TA 3000), at a heating rate of 20° C. per minute.
The viscosity index (J) was determined using 0.5 wt.% solutions of the polyamides in a 1:1 (by wt.) phenol/o-dichlorobenzene mixture at 25° C. (DIN 53 728).
Hot-forming stability (Vicat A/50) was determined according to the procedure of DIN 53 460.
Water uptake was determined gravimetrically according to the procedure of DIN 53 495 (ISO 150 62).
Example A is a comparison example.
EXAMPLES
Example 1
A 4 g amount of an aromatic polyamide comprised of units of isophthalic acid and 4,4'-bis(4-aminophenoxy)diphenylsulfone in a molar ratio of 1:1 (Tg=252° C., J-value=65 cc/g) and 36 g of an amorphous polyamide comprised of units of terephthalic acid and trimethyl-1,6-hexanediamine in a molar ratio of 1:1 (Tg=152° C., J-value=14.2 cc/g) were intermixed in a laboratory kneader (supplied by the firm Haake) for 15 min at 320° C. under a nitrogen atmosphere. The result was a homogeneous blend. Only one Tg value could be determined according to DSC. ##EQU1##
Examples 2-9
Examples 2-9 were carried out analogously to Example 1, but the mixing ratio of aromatic polyamide to amorphous polyamide was varied. The proportions of the individual components and the properties of the resulting molding compounds are indicated in Table 1.
TABLE 1______________________________________ PA* APA** J-value T.sub.gExample (wt %) (wt %) (cm.sup.3 /g) (°C.)______________________________________1 10 90 84 1552 20 80 103 1583 30 70 97 1644 40 60 74 1825 50 50 49 1966 60 40 61 2057 70 30 57 2148 80 20 43 2229 90 10 50 238______________________________________ PA* Aromatic polyamide APA** Amorphous polyamide
Examples 10-12
Granular mixtures corresponding to each of Examples 1-3, respectively, were mixed in the melt on a dual-screw kneader (type ZSK 30 supplied by Werner and Pfleiderer) at 340° C. housing temperature and a throughput of 7 kg/hr, followed by granulation. Under these conditions a transparent blend was obtained which was processed to form test bodies. The properties of these test bodies are indicated in Table 2.
TABLE 2______________________________________Ex- PA* APA** T.sub.g VICAT Water VICATample (wt %) (wt %) (°C.) A/50 (°C.) uptake A/50 (°C.)______________________________________10 10 90 155 149 5.26 9011 20 80 158 153 4.78 9812 30 70 164 160 4.37 108A 0 100 154 147 5.77 87______________________________________ PA* Aromatic polyamide APA** Amorphous polyamide
Having now fully described the invention, it will be apparent to one of ordinary skill in the art that many changes and modifications can be made thereto without departing from the spirit or scope of the invention as set forth herein. | 1. A polyamide molding compound, comprised of:
(I) an aromatic polyamide having the structure ##STR1## where n is a number between 5 and 500; X represents --SO 2 -- or --CO--, and
Y represents --O-- or --S--; and (II) an amorphous polyamide. | 2 |
CROSS-REFERENCE TO RELATED APPLICATION(S)
[0001] This application claims priority to U.S. Provisional Application No. 61/063,632, filed Feb. 5, 2008 and entitled “Weight Activated Restraining Pillow”.
BACKGROUND
[0002] The present invention relates to pillows or cushions for adults, children, infants, or animals. More specifically, the present invention relates to pillows having peripheral guards for restraining adults, children, infants, or animals.
[0003] Pillows have a wide variety of uses. For example, pillows are used almost universally when sleeping to support the head. Pillows may also be used to support other things as well. A variety of cushions, pillows, and pads have been used by both infants and adults which can be conveniently transported and placed on the ground or on a bed to provide a comfortable resting. Because small infants and even toddlers tend to roll off the edge of a bed or other surface without some kind of guard around the periphery, pillows designed especially for use by infants preferably include a raised edge which will block the baby from rolling off the pillow and onto the floor. Rolled up blankets, towels, or pillows are often placed around a small child to prevent the child from falling off a bed unequipped with rails, or similar surface. Traditional adult pillows used singularly are ill suited for such a task and are not recommended for use with babies.
SUMMARY
[0004] An embodiment of the present invention is a weight activated restraining pillow including a peripheral cushion area, fill material located within the peripheral cushion area, and a central sling holding area located inside of the peripheral area. The cushion has a top, a bottom, a first side, and a second side. The first side and the second side are substantially parallel and extend between the top and the bottom. The sling is defined in part by a first seam extending substantially parallel to the first side and a second seam extending substantially parallel to the second side. The first seam and the second seam separate the sling from the cushion so that when a weighted object is received into the sling, the first side and the second side of the cushion area draw inward toward the weighted object within the sling.
[0005] Another embodiment of the present invention is weight activated restraining pillow including a cushion having a padded region and an unpadded region. The padded region generally surrounds the unpadded region. A first longitudinal seam defines a first side of the unpadded region and a second longitudinal seam defines a second side of the unpadded region. When a weighted object is placed centrally within the unpadded region, it draws the first longitudinal seam and second longitudinal seam inwards toward one another.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] FIG. 1 is a perspective view of a weight activated restraining pillow with an infant placed on its back therein.
[0007] FIG. 2 is a perspective view of a weight activated restraining pillow with an infant placed on its stomach therein.
[0008] FIG. 3 is a perspective view of the top of a weight activated restraining pillow.
[0009] FIG. 4 is a perspective view of the pillow illustrated in FIG. 3 covered with a case.
[0010] FIG. 5 is a plan view of the bottom of the pillow illustrated in FIG. 3 .
[0011] FIG. 6 is an elevation view of a side of the pillow illustrated in FIG. 3 .
[0012] FIG. 7 is an elevation view of an end of the pillow generally perpendicular to the side illustrated in FIG. 6 .
[0013] FIGS. 8A and 8B are a cross-sectional views of an alternative embodiment of a weight activated restraining pillow.
DESCRIPTION
[0014] FIG. 1 is a perspective view of weight activated restraining pillow 12 with infant B placed on its back therein. Depicted in FIG. 1 are: infant B, pillow 12 having cushion 14 and sling 16 . When infant B is placed on its back in sling 16 , cushion 14 moves inward such that pillow 12 gently contacts and comforts infant B.
[0015] In the embodiment depicted, infant B is lying on its back on top of weight activated restraining pillow 12 . Together, peripheral cushion area 14 and central sling area 16 form pillow 12 , which can be used as a positioning device and/or a sensory stimulant for infant B. Peripheral cushion area 14 is approximately oval shaped, although the invention is not so limited. In FIG. 1 , pillow 12 is sized for an infant such that sling 16 is located mainly beneath infant B and cushion 14 is drawn slightly inward and surrounding infant B. Cushion or padded area 14 is stuffed with fill material such as but not limited to poly fill. In an alternate embodiment, cushion 14 is a vinyl tube that is inflated with air or filled with common pillow contents such as feathers or Styrofoam beads, which may be flame retardant. Sling or unpadded area 16 is not stuffed with fill and therefore, provides a relatively flat holding area for placement of infant B. When infant B is placed on top of pillow 12 , the weight of infant B causes sling 16 to deform downwards and cushion 14 to move centrally to contact infant B. As depicted in FIG. 1 , pillow 12 promotes spinal alignment of infant B and can also provide physical comfort through light touch of cushion 14 to infant B.
[0016] FIG. 2 is a perspective view of weight activated restraining pillow 12 , with infant B placed on its stomach therein. Depicted in FIG. 2 are: infant B, pillow 12 , cushion 14 and sling 16 . When infant B is placed on its stomach in sling 16 , cushion 14 is pulled inwards toward infant B such that pillow 12 gently contacts and comforts infant B.
[0017] Cushion 14 and sling 16 remain in the arrangement described above with reference to FIG. 1 where peripheral cushion area 14 surrounds central sling area 16 . Infant B, however, is now depicted on its stomach, otherwise known as “tummy time” position. When placed on its stomach, a portion of infant B extends over a top of cushion 14 while a remaining portion of infant B is located on top of sling 16 . Less weight is centrally located over sling 16 and therefore, sling 16 deforms less than when infant B is placed completely within sling 16 . Since infant B extends over cushion 14 , cushion 14 also deforms or compresses slightly under infant B. Compression of cushion 14 keeps back of infant B at an angle less than about 45 degrees and therefore, not strained or compressed. Deformation of cushion 14 also keeps infant B close to a surface or floor located beneath pillow 12 , which can be less frightening than being elevated at a great distance above a surface.
[0018] FIG. 3 is a plan view of the top of weight activated restraining pillow 12 . Depicted in FIG. 3 are components of pillow 12 as seen from the top: cushion 14 , sling 16 , top 18 , bottom 20 , first side 22 , second side 24 , first seam 26 , second seam 26 and third seam 30 . Pillow 12 is configured to cradle an infant, child, adult, or non-human animal such as a pet.
[0019] Pillow 12 includes peripheral cushion 14 and center sling 16 . For descriptive purposes, pillow 12 can be divided into top 18 , bottom 20 , first side 22 and second side 24 . As depicted, first side 22 and second side 24 are substantially parallel to each other yet spaced apart and extending between top 18 and bottom 20 . Sling 16 is surrounded by cushion 14 and at least partially defined by first seam 26 extending substantially parallel to first side 22 and second seam 28 extending substantially parallel to second side 24 . First seam 26 and second seam 28 separate sling 16 from cushion 14 so that the fill located within cushion 14 does not significantly spread out into sling 16 . In the embodiment depicted, no seaming separates top 18 and bottom 20 from sling 16 , thereby ensuring that the fill forms a gentle slope between cushion 14 and sling 16 at top 18 and bottom 20 . Located in a center of sling, in between and substantially parallel to first seam 26 and second seam 28 , is third seam 30 . In the depicted embodiment, third seam 30 is slightly longer than first seam 26 and second seam 30 , which have similar lengths. In other embodiments, first seam 26 , second seam 28 , and third seam 30 can have approximately equal lengths.
[0020] When a weighted object is placed approximately over third seam 30 , first seam 26 and second seam 28 draw inward toward third seam 30 . Depending on the size and weight of the object placed in sling 16 , first side 22 and second side 24 of cushion 14 can be pulled centrally or horizontally such that they hug, cuddle, or cradle the weighted object located in sling 16 . The sensory stimulation provided by contact with cushion 14 can be a source of comfort to fussy and/or premature infants, humans with autism or dementia, and even household pets. Furthermore, the cradling effect or U-shaped nature of sling 16 restricts movement such that objects placed within sling 16 cannot easily turn over or roll out of pillow 12 onto a surrounding surface. The amount of pressure exerted on an object by the sling effect is proportional to the size and weight of the object.
[0021] FIG. 4 is a plan view of weight activated restraining pillow 12 covered with case 24 . Case 24 completely surrounds and encloses pillow 12 , thereby protecting pillow 12 from spills and stains. Case 24 is easily removed for cleaning. Both pillow 12 and case 24 are washable. Furthermore, case 24 can provide a desired surface texture or design for pillow 12 .
[0022] FIG. 5 is a plan view of the bottom of weight activated restraining pillow 12 . Depicted in FIG. 5 are components of pillow 12 as seen from the bottom: cushion 14 B, sling 16 B, top 18 B, bottom 20 B, first side 22 B, second side 24 B, first seam 26 B, second seam 26 B and third seam 30 B. Pillow 12 is configured to place slight peripheral pressure on an infant, child, adult, or non-human animal such as a pet located on top of pillow 12 .
[0023] Bottom of pillow 12 is similar to top of pillow 12 and thus, cushion 14 B, sling 16 B, top 18 B, bottom 20 B, first side 22 B, second side 24 B, first seam 26 B, second seam 26 B and third seam 30 B are arranged as described above. Pillow 12 can be constructed from a singular piece of cloth material, or alternately two pieces of material such as a top sheet and bottom sheet that are mirror patterns of one another. The cloth or textile material is stitched to create perimeter cushion area 14 and seams 26 , 28 and 30 . In the embodiment depicted, first seam 26 and second seam 28 have similar lengths between about 10 inches and about 15 inches, more preferably between about 12 inches and 14 inches. Third seam 30 is longer than first seam 26 and second seam 28 . Third seam 30 has a length between about 15 inches and about 20 inches, more preferably between about 16 inches and about 18 inches. A space between third seam 30 and first seam 28 , as well as a space between third seam 30 and second seam 26 , is between about 2 inches and about 5 inches, more preferably between about 3 inches and 4 inches. A small gap is left to stuff perimeter 14 with appropriate fill. Alternately, fill is placed in position and then the material is stitched to create the desired shape. The construction of pillow 12 is described further below with reference to FIGS. 6-8 .
[0024] FIG. 6 is an elevation view of first side 22 of pillow 12 and FIG. 7 is an elevation view of top 18 of the pillow generally perpendicular to the first side 22 . Depicted in FIG. 6 are: pillow 12 , top 18 , bottom 20 , first side 22 and fourth seam 32 . Depicted in FIG. 7 are: pillow 12 , top 18 , first side 22 , second side 24 and fourth seam 32 . Pillow 12 cradles objects that are placed centrally on a top surface of pillow 12 .
[0025] Described below are dimensions of pillow 12 preferable for use with infants, although the invention is not so limited. Top 18 and bottom 20 are substantially parallel to each other and have similar lengths between about 15 inches and about 20 inches, more preferably between about 16 inches and about 18 inches. Since top 18 is similar to bottom 20 , only top 18 is shown in FIG. 7 although the below discussion relates similarly to bottom 20 . First side 22 and second side 24 are substantially parallel to each other and have similar lengths between about 20 inches and about 30 inches, more preferably between about 24 inches and about 28 inches. Since first side 22 is similar to second side 24 , only first side 22 is shown in FIG. 6 although the below discussion relates similarly to second side 24 . As shown in FIG. 6 , fourth seam 32 extends around an approximate center of first side 22 from top 18 to bottom 20 . As shown in FIG. 7 , fourth seam 32 continues around top 18 . In fact, forth seam 32 extends the length of second side 24 from top 18 to bottom 20 and continues around bottom 20 , such that fourth seam 32 is continuous around an entire perimeter of pillow 12 . Stitching pattern, including fourth seam 32 , keeps filling within cushion 14 and out of sling 16 . In alternative embodiments, fourth seam 32 is partially or wholly omitted. Fourth seam 32 is substantially parallel to a surface on which pillow 12 is resting and maintains fill within cushion 14 . Together, top 18 , bottom 20 , first side 22 and second side 24 are continuous and defined at the periphery by fourth seam 32 , which aids in formation of cushion 14 or the “guard rail” portion of pillow 12 .
[0026] FIG. 8A is a cross section of pillow 12 in an un-weighted position. FIG. 8B is a cross section of pillow 12 in a weight activated position. Depicted in FIGS. 8A and 8B are pillow 12 , cushion 14 , sling 16 , first side 22 , second side 24 , first seam 26 , second seam 28 , third seam 30 and fill 34 . Additionally depicted in FIG. 8B is weight W.
[0027] As described above, pillow 12 includes cushion region 14 surrounding sling region 16 . Cushion 14 is stuffed with fill 34 and is approximately circular in cross section. When pillow 12 is sized for use with infant B, the following dimensions are preferable, although the invention is not so limited and pillow 12 can be sized differently depending on intended use. Cushion 14 can have a diameter between about 3 inches and about 6 inches, more preferably between about 4 inches and about 5 inches. In contrast, sling 16 is not stuffed and is substantially flat. In FIG. 8A , sling 16 is un-weighted and suspended above a surface on which cushion 14 is resting. Without weight activation from weight W, sling 16 is between about 1 inch and about 4 inches above a surface, more preferably between about 2 inches and about 3 inches. In FIG. 8B , sling is weighted by weight W, and since weight W is sufficient to deform sling 16 into contact with a surface upon which cushion 14 is resting, there is no longer any vertical distance between sling 16 and the surface. The amount which sling 16 is deformed toward the surface is proportional to the size and weight of weight W.
[0028] When weight W is placed into and deforming sling 16 , cushion 14 moves centrally or horizontally inwards toward weight W. Usually, weight W is centrally located approximately over third seam 30 such that first seam 26 and second seam 28 place approximately equal tension on first side 22 and second side 24 , respectively. Sling 16 dips in the center when weighted by weight W such that it forms a U-shape. The vertical location of an intersection between first seam 26 and first side 22 , as well as the vertical location of an intersection between second seam 28 and second side 24 , are essentially unchanged between FIG. 8A and FIG. 8B . Maintaining vertical location of first seam 26 and second seam 28 regardless of weight activation ensures that cushion 14 is not moving vertically and therefore, not smothering weight W. The distance that is changed between FIGS. 8A and 8B , however, is the horizontal distance between first side 22 and second side 24 . In FIG. 8A , the horizontal distance between first seam 26 and second seam 28 is between about 5 and about 10 inches, more preferably between about 6 and about 8 inches. In contrast, FIG. 8B shows a substantially reduced horizontal distance between first seam 26 and second seam, which is between about 2 inches and about 8 inches, more preferably between about 4 inches and about 6 inches. Thus, weight W causes sling 16 to deform downwardly toward a surface on which cushion 14 is resting, thereby bringing first side 22 and second side 24 horizontally closer to one another. Lowering of sling 16 and inward movement of cushion 14 produces a sensory stimulus similar to cuddling, snuggling, or cradling within sling 16 .
[0029] Pillow 12 can be sized to cradle anyone from a premature infant to a full-sized adult. Furthermore, pillow 12 can be configured to provide the same sensory stimulation to non-human animals such as, but not limited, household pets. Although the present invention has been described with reference to preferred embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention. | Weight restraining pillow has a filled outer perimeter area encompassing a central sling area. The sling is defined in part by two generally parallel outer seams adjacent the outer perimeter, and an inner seam located between the outer seams which help hold the fill of the perimeter in place. When a weighted object is placed on the sling, the perimeter is drawn inward toward the object placed therein. | 0 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of U.S. Provisional Application No. 61/611,863, filed Mar. 16, 2012, having the same title, and having the same inventors, and which is incorporated herein by reference in its entirety.
FIELD OF THE DISCLOSURE
[0002] The present disclosure relates generally to synthetic jet ejectors, and more particularly to systems and methods for the augmentation of fan-based thermal management systems with synthetic jet ejectors.
BACKGROUND OF THE DISCLOSURE
[0003] A variety of thermal management devices are known to the art, including conventional fan based systems, piezoelectric systems, and synthetic jet ejectors. The latter type of system has emerged as a highly efficient and versatile thermal management solution, especially in applications where thermal management is required at the local level.
[0004] Various examples of synthetic jet ejectors are known to the art. Earlier examples are described in U.S. Pat. No. 5,758,823 (Glezer et al.), entitled “Synthetic Jet Actuator and Applications Thereof”; U.S. Pat. No. 5,894,990 (Glezer et al.), entitled “Synthetic Jet Actuator and Applications Thereof”; U.S. Pat. No. 5,988,522 (Glezer et al.), entitled Synthetic Jet Actuators for Modifying the Direction of Fluid Flows”; U.S. Pat. No. 6,056,204 (Glezer et al.), entitled “Synthetic Jet Actuators for Mixing Applications”; U.S. Pat. No. 6,123,145 (Glezer et al.), entitled Synthetic Jet Actuators for Cooling Heated Bodies and Environments”; and U.S. Pat. No. 6,588,497 (Glezer et al.), entitled “System and Method for Thermal Management by Synthetic Jet Ejector Channel Cooling Techniques”.
[0005] Further advances have been made in the art of synthetic jet ejectors, both with respect to synthetic jet ejector technology in general and with respect to the applications of this technology. Some examples of these advances are described in U.S. 20100263838 (Mahalingam et al.), entitled “Synthetic Jet Ejector for Augmentation of Pumped Liquid Loop Cooling and Enhancement of Pool and Flow Boiling”; U.S. 20100039012 (Grimm), entitled “Advanced Synjet Cooler Design For LED Light Modules”; U.S. 20100033071 (Heffington et al.), entitled “Thermal management of LED Illumination Devices”; U.S. 20090141065 (Darbin et al.), entitled “Method and Apparatus for Controlling Diaphragm Displacement in Synthetic Jet Actuators”; U.S. 20090109625 (Booth et al.), entitled Light Fixture with Multiple LEDs and Synthetic Jet Thermal Management System”; U.S. 20090084866 (Grimm et al.), entitled Vibration Balanced Synthetic Jet Ejector”; U.S. 20080295997 (Heffington et al.), entitled Synthetic Jet Ejector with Viewing Window and Temporal Aliasing”; U.S. 20080219007 (Heffington et al.), entitled “Thermal Management System for LED Array”; U.S. 20080151541 (Heffington et al.), entitled “Thermal Management System for LED Array”; U.S. 20080043061 (Glezer et al.), entitled “Methods for Reducing the Non-Linear Behavior of Actuators Used for Synthetic Jets”; U.S. 20080009187 (Grimm et al.), entitled “Moldable Housing design for Synthetic Jet Ejector”; U.S. 20080006393 (Grimm), entitled Vibration Isolation System for Synthetic Jet Devices”; U.S. 20070272393 (Reichenbach), entitled “Electronics Package for Synthetic Jet Ejectors”; U.S. 20070141453 (Mahalingam et al.), entitled “Thermal Management of Batteries using Synthetic Jets”; U.S. 20070096118 (Mahalingam et al.), entitled “Synthetic Jet Cooling System for LED Module”; U.S. 20070081027 (Beltran et al.), entitled “Acoustic Resonator for Synthetic Jet Generation for Thermal Management”; U.S. 20070023169 (Mahalingam et al.), entitled “Synthetic Jet Ejector for Augmentation of Pumped Liquid Loop Cooling and Enhancement of Pool and Flow Boiling”; U.S. 20070119573 (Mahalingam et al.), entitled “Synthetic Jet Ejector for the Thermal Management of PCI Cards”; U.S. 20070119575 (Glezer et al.), entitled “Synthetic Jet Heat Pipe Thermal Management System”; U.S. 20070127210 (Mahalingam et al.), entitled “Thermal Management System for Distributed Heat Sources”; U.S. 20070141453 (Mahalingam et al.), entitled “Thermal Management of Batteries using Synthetic Jets”; U.S. Pat. No. 7,252,140 (Glezer et al.), entitled “Apparatus and Method for Enhanced Heat Transfer”; U.S. Pat. No. 7,606,029 (Mahalingam et al.), entitled “Thermal Management System for Distributed Heat Sources”; U.S. Pat. No. 7,607,470 (Glezer et al.), entitled “Synthetic Jet Heat Pipe Thermal Management System”; U.S. Pat. No. 7,760,499 (Darbin et al.), entitled “Thermal Management System for Card Cages”; U.S. Pat. No. 7,768,779 (Heffington et al.), entitled “Synthetic Jet Ejector with Viewing Window and Temporal Aliasing”; U.S. Pat. No. 7,784,972 (Heffington et al.), entitled “Thermal Management System for LED Array”; and U.S. Pat. No. 7,819,556 (Heffington et al.), entitled “Thermal Management System for LED Array”.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] FIGS. 1A-1C are illustrations depicting the manner in which a synthetic jet actuator operates.
[0007] FIG. 2 is an illustration of a server chassis equipped with a fan-based thermal management system.
[0008] FIG. 3 is an illustration of a server chassis equipped with a fan-based thermal management system augmented by synthetic jet cooling.
[0009] FIG. 4 is an illustration of the air flow in the vicinity of a heat sink and heat source (microprocessor) construct in a fan-based thermal management system.
[0010] FIG. 5 is an illustration of the air flow in the vicinity of a heat sink and heat source (microprocessor) construct in a fan-based thermal management system which is augmented by a synthetic jet ejector.
[0011] FIG. 6 is an illustration of an experimental set-up for measuring the effect of augmenting a fan-based thermal management system with a synthetic jet ejector.
[0012] FIG. 7 is a graph of thermal resistance (in C/W) as a function of mean fan flow (measured in LFM) which illustrates the improvement in thermal resistance due to augmentation of a fan-based thermal management system with a synthetic jet ejector.
[0013] FIG. 8 is a graph of % improvement in thermal performance as a function of the ratio of jet LFM to mean LFM which illustrates the percent improvement in heat dissipation as a function of jet/fan LFM ratio for the augmentation of a fan-based thermal management system with a synthetic jet ejector.
[0014] FIG. 9 is an illustration of a particular, non-limiting embodiment of a server equipped with a fan-based thermal management system which is augmented by a synthetic jet ejector thermal management system.
[0015] FIG. 10 is a graph of % improvement in heat dissipation as a function of baseline fan LFM for both predicted and measured values, which illustrates the improvements in heat dissipation provided by synthetic jet ejectors at low mean flow rates.
[0016] FIG. 11 is a graph of thermal resistance (in C/W) as a function of baseline fan RPM for a thermal management system featuring only fan-based cooling, and a thermal management system featuring both fan-based cooling and synthetic jet ejector cooling.
[0017] FIG. 12 is a table showing the power consumption and acoustical footprint for a thermal management system featuring only fan-based cooling, and a thermal management system featuring both fan-based cooling and synthetic jet ejector cooling.
[0018] FIG. 13 is an illustration of the effect on cooling system reliability (as measured by estimated lifetimes) for thermal management systems featuring fan cooling only, fan-assisted augmentation, and synthetic jet ejector assisted augmentation.
[0019] FIG. 14 is an illustration of a first embodiment of a synthetic jet ejector equipped with pipes for remote cooling.
[0020] FIG. 15 is an illustration of a second embodiment of a synthetic jet ejector equipped with pipes for remote cooling.
SUMMARY OF THE DISCLOSURE
[0021] In one aspect, a computing device is provided which comprises (a) a chassis having an array of printed circuit boards (PCBs) disposed therein, wherein said chassis has a first wall with a first opening therein, and a second wall with a second opening therein, wherein each PCB is equipped with a microprocessor and a heat sink, and wherein each heat sink comprises a plurality of heat fins that define a plurality of longitudinal channels; (b) a fan which creates a fluidic flow that enters through said first opening and exits through said second opening, said fluidic flow being essentially parallel the longitudinal axes of said plurality of longitudinal channels; and (c) a synthetic jet ejector which directs at least one synthetic jet through at least one of said plurality of channels.
[0022] In another aspect, a system for testing the effect of synthetic jet cooling in a thermal management system is provided. The system comprises (a) a conduit having a heat sink disposed therein which is in thermal contact with a heat source; (b) a heat source in thermal contact with said heat sink; (c) a synthetic jet ejector which directs a synthetic jet onto or across a surface of said heat sink; (d) a fan which creates an air flow through said conduit from a direction upstream from said heat sink to a direction downstream from said heat sink; and (e) a velocity probe.
DETAILED DESCRIPTION
[0023] The systems, devices and methodologies disclosed herein utilize synthetic jet actuators or synthetic jet ejectors. Prior to describing these systems, devices and methodologies, a brief explanation of a typical synthetic jet ejector, and the manner in which it operates to create a synthetic jet, may be useful.
[0024] FIG. 1 illustrates the operation of a typical synthetic jet ejector in forming a synthetic jet. As seen therein, the synthetic jet ejector 101 comprises a housing 103 which defines and encloses an internal chamber 105 . The housing 103 and chamber 105 may take virtually any geometric configuration, but for purposes of discussion and understanding, the housing 103 is shown in cross-section in FIG. 1 to have a rigid side wall 107 , a rigid front wall 109 , and a rear diaphragm 111 that is flexible to an extent to permit movement of the diaphragm 111 inwardly and outwardly relative to the chamber 105 . The front wall 109 has an orifice 113 therein which may be of various geometric shapes. The orifice 113 diametrically opposes the rear diaphragm 111 and fluidically connects the internal chamber 105 to an external environment having ambient fluid 115 .
[0025] The movement of the flexible diaphragm 111 may be achieved with a voice coil or other suitable actuator, and may be controlled by a suitable control system 117 . The diaphragm 111 may also be equipped with a metal layer, and a metal electrode may be disposed adjacent to, but spaced apart from, the metal layer so that the diaphragm 111 can be moved via an electrical bias imposed between the electrode and the metal layer. Moreover, the generation of the electrical bias can be controlled by any suitable device including, but not limited to, a computer, logic processor, or signal generator. The control system 117 can cause the diaphragm 111 to move periodically or to modulate in time-harmonic motion, thus forcing fluid in and out of the orifice 113 .
[0026] Alternatively, a piezoelectric actuator could be attached to the diaphragm 111 . The control system would, in that case, cause the piezoelectric actuator to vibrate and thereby move the diaphragm 111 in time-harmonic motion. The method of causing the diaphragm 111 to modulate is not particularly limited to any particular means or structure.
[0027] The operation of the synthetic jet ejector 101 will now be described with reference to FIGS. 1 b - 1 c . FIG. 1 b depicts the synthetic jet ejector 101 as the diaphragm 111 is controlled to move inward into the chamber 105 , as depicted by arrow 125 . The inward motion of the diaphragm 111 reduces the volume of the chamber 105 , thus causing fluid to be ejected through the orifice 113 . As the fluid exits the chamber 105 through the orifice 113 , the flow separates at the (preferably sharp) edges of the orifice 113 and creates vortex sheets 121 . These vortex sheets 121 roll into vortices 123 and begin to move away from the edges of the orifice 109 in the direction indicated by arrow 119 .
[0028] FIG. 1 c depicts the synthetic jet ejector 101 as the diaphragm 111 is controlled to move outward with respect to the chamber 105 , as depicted by arrow 127 . The outward motion of the diaphragm 111 causes the volume of chamber 105 to increase, thus drawing ambient fluid 115 into the chamber 105 as depicted by the set of arrows 129 . The diaphragm 111 is controlled by the control system 117 so that, when the diaphragm 111 moves away from the chamber 105 , the vortices 123 are already removed from the edges of the orifice 113 and thus are not affected by the ambient fluid 115 being drawn into the chamber 105 . Meanwhile, a jet of ambient fluid 115 is synthesized by the vortices 123 , thus creating strong entrainment of ambient fluid drawn from large distances away from the orifice 109 .
[0029] It has now been found that synthetic jet ejectors may be utilized advantageously in some applications to augment the fluidic flow provided by fan-based thermal management systems. This is especially so in applications involving the thermal management of computing devices, such as servers, where the turbulent, localized flow provided by synthetic jet ejectors complements the global fluidic flow provided by fans by enhancing heat transfer through boundary layer disruption along the surfaces of a heat sink.
[0030] FIG. 2 is an illustration of a prior art server chassis which relies on fan cooling alone for the thermal management thereof. As seen therein, the server chassis 201 depicted comprises a housing 203 having an inlet portion 205 and an outlet portion 207 . A fan 209 is disposed adjacent to the outlet portion 207 .
[0031] The housing 203 has a plurality of PCB boards 211 disposed therein. Each PCB board 211 is equipped with the circuitry needed to operate the server or a portion thereof, which typically includes a microprocessor 213 . Each PCB board 211 is further equipped with a heat sink 215 which is in thermal contact with said microprocessor 213 .
[0032] In operation, the fan 209 creates a flow of air which enters the housing 203 by way of the inlet portion 205 and exits the housing 203 by way of the outlet portion 207 . In doing so, the flow of air traverses the PCB boards 211 and the heat sinks 215 disposed thereon, thus cooling the heat sinks 215 and hence the microprocessors 213 .
[0033] Although systems of the type depicted in FIG. 2 have been used extensively in the art, the limitations of these systems have become apparent over time. In particular, as the size of microelectronic devices has continued to decrease, newer generations of servers have been introduced with increasingly greater circuit densities. This has significantly increased the thermal load within server chassis to the point where fan-based thermal management systems can no longer provide adequate thermal management to enable these devices to operate at optimal conditions.
[0034] The problem is especially problematic with older servers. In particular, while it is frequently desirable to retrofit existing servers with improved PCB boards offering greater performance, the thermal footprint associated with these devices often severely taxes the thermal management system of the server, which may have been designed to handle significantly smaller thermal loads.
[0035] It has now been found that synthetic jet ejectors provide an efficient and effective solution to these problems. In particular, the performance of fan-based thermal management systems is often hindered by boundary layer conditions, which limit the ability of a heat sink to transfer heat to the ambient environment. However, the synthetic jets associated with a synthetic jet ejector may be used to effectively disrupt such boundary layers, thus providing a more efficient transfer of heat to the ambient environment. Hence, the suitable placement of synthetic jet ejectors in a fan-based thermal management system may be used to efficiently augment the performance of such a system, thus allowing it to handle a larger thermal load. Moreover, synthetic jet ejectors are small enough to be mounted in a sever chassis near a heat source, or may utilize a distribution system to distribute synthetic jets to the location of one or more heat sources. Consequently, thermal management systems are especially useful in retrofitting existing server chassis which are equipped with only a fan-based thermal management system.
[0036] FIG. 3 is an illustration of a particular, non-limiting embodiment of a server chassis made in accordance with the teachings herein which relies on a fan-based thermal management system, in conjunction with a synthetic jet based thermal management system, for the thermal management thereof. As seen therein, the server chassis 301 depicted comprises a housing 303 having an inlet portion 305 and an outlet portion 307 . A fan 309 is disposed adjacent to the outlet portion 307 .
[0037] The housing 303 has a plurality of PCB boards 311 disposed therein. Each PCB board 311 is equipped with the circuitry needed to operate the server or a portion thereof, which typically includes one or more microprocessors 313 . Each PCB board 311 is further equipped with one or more heat sinks 315 which are in thermal contact with said microprocessors 313 .
[0038] The server chassis 301 in this embodiment is further equipped with one or more synthetic jet ejectors 317 which emit one or more synthetic jets. These synthetic jets may be directed onto, across or near the surfaces of the heat sinks 315 , either directly or through the use of a synthetic jet distribution system.
[0039] In operation, the fan 309 creates a global flow of air which enters the housing 303 by way of the inlet portion 305 and exits the housing 303 by way of the outlet portion 307 . In doing so, the flow of air traverses the PCB boards 311 and the heat sinks 315 disposed thereon. Meanwhile, the synthetic jets create a localized, turbulent flow of fluid which disrupts the boundary layer over the surfaces of the heat sinks 315 , thus cooling the heat sinks 315 and hence the microprocessors 313 and facilitating the transfer of heat to the external environment. The highly directional flow of fluid attendant to the creation of a synthetic jet also moves the heated fluid a significant distance away from the heat source, where it may be readily rejected to the external environment by the fan-based thermal management system.
[0040] A further advantage of the system of FIG. 3 may be appreciated with respect to FIGS. 4-5 which illustrate, respectively, the flow characteristics of the systems of FIGS. 2 and 3 . As seen therein, in the system of FIG. 2 (depicted in FIG. 4 ), the fluidic flow provided by the fan-based thermal management system only partially penetrates the channels and spaces between adjacent fins of the heat sink. By contrast, as seen in the system of FIG. 3 (depicted in FIG. 5 ), the use of a synthetic jet ejector causes the fluidic flow to more efficiently penetrate the channels and spaces between adjacent fins of the heat sink, thus resulting in more efficient transfer of heat to the external environment.
[0041] The improved heat transfer provided by the system of FIG. 3 over the system of FIG. 2 provides other advantages as well. In particular, such a system enables the use of smaller fans which can operate at slower speeds. This, in turn, reduces the noise attendant to the use of a fan, reduces the cost of the system, and improves the reliability of the system. Moreover, the improved heat transfer coefficients and flow rates attendant to the system of FIG. compared to the system of FIG. 2 ) enables the use in the server chassis of PCB boards having higher processor power. In addition, the synthetic jet ejector system may be provided as a retrofit solution which is hot swappable.
[0042] FIG. 6 illustrates a particular, non-limiting embodiment of an experimental set-up that may be used to determine the improvements achievable with a system of the type depicted in FIG. 3 . The experimental set-up 601 depicted therein comprises a housing 603 having an inlet 605 and an outlet 607 which are in fluidic communication with each other by way of a test section 609 . The outlet 607 is equipped with a fan 611 which creates a global flow of fluid through the test section 609 . The area of the test section 609 may be varied from one experiment to another, but may be, for example, an 8×8 region.
[0043] The test section 609 is further equipped with a heat source 613 , a heat sink 615 and a synthetic jet ejector 617 which directs a synthetic jet into each of the channels formed by adjacent fins of the heat sink 615 . The heat source 613 will typically be instrumented to provide a known output of heat so the ability of the system to transfer heat may be readily measured. The test section 609 is further equipped with a velocity probe 619 to measure fluid velocity upstream of the heat sink 615 .
[0044] The experimental set-up 601 depicted in FIG. 6 is particularly useful for measuring the improvements in heat transfer and efficiency in a system of the type depicted in FIG. 3 as compared to a system of the type depicted in FIG. 2 . Advantageously, the experimental set-up 601 allows the wind tunnel cross-section may be varied to achieve different bypass ratios. Moreover, the synthetic jet ejector 617 is placed upstream of the heat sink 615 , thus efficiently directing fluidic flow into the heat sink 615 . In addition, the flow velocities and heat sink thermals may be readily measured.
[0045] FIGS. 7-8 depict results achieved with the experimental setup of FIG. 6 in comparing the relative performances of the systems of FIGS. 2 and 3 . Thus, FIG. 7 shows the improvement in thermal jet resistance due to jet augmentation in the form of thermal resistance (in C/W) as a function of mean fan flow (in linear feet per minute, or LFM). As seen therein, jet augmentation significantly decreases the thermal resistance of the heat sink.
[0046] FIG. 8 illustrates the percentage improvement in heat dissipation as a function of jet/fan LFM ratio achievable with a system of the type depicted in FIG. 3 . The graph shown therein is of the percent improvement in thermal performance as a function of the ratio of jet LFM to mean LFM. As seen therein, thermal performance increases significantly with the ratio of jet LFM to mean LFM, though the effect begins to taper off as the ratio of jet LFM to mean LFM increases. It will be appreciated from the foregoing that the ratio of jet velocity to free stream flow velocity is a key metric for determining the performance improvement due to jet augmentation.
[0047] FIG. 9 depicts a server utilized for a series of synthetic jet augmentation studies in accordance with the teachings herein. The server is an 800 W Newisys 4300 quad-socket, 3U, AMD OPTERON™ rack mounted model. The device was utilized in conjunction with the experimental set-up depicted in FIG. 6 , and using an inlet speed which varied from 560 LFM (5500 RPM) to 800 LFM (9000 RPM). The results of this experiment are depicted in FIGS. 10-12 .
[0048] FIG. 10 illustrates the percent improvement in system heat dissipation achievable with the foregoing setup, and includes both measured and predicted values for the percent improvement in heat dissipation as a function of baseline fan flow (in LFM). As seen therein, the use of a synthetic jet ejector provides improvements in heat dissipation at low mean flow rates.
[0049] FIG. 11 shows the thermal resistance (in C/W) as a function of baseline fan flow (in RPM), and illustrates the improvement in thermal performance achievable with the foregoing setup when used with synthetic jet augmentation as compared to fan-only thermal management. FIG. 12 shows the equivalent thermal performance, and hence illustrates the cooling system power consumption and acoustics.
[0050] As seen by the results of FIGS. 11-12 , the use of synthetic jets helped to reduce the speed of system fans from 9000 RPM to 6500 RPM. This resulted in a drop in cooling system power consumption from 108 W to 62 W. This also resulted in a drop in system acoustics from 75 dBA to 65 dBA. Hence, the augmented system was both more energy efficient and quieter than the corresponding fan-only system.
[0051] FIG. 13 illustrates the calculated effect of synthetic jet augmentation on cooling system reliability. The calculations assume a server of the type depicted in FIG. 9 , a fan reliability of about 40,000 hours (L10 or 58 ppm), a synthetic jet ejector reliability of 250,000 hours (L10 or 10 ppm), a single main fan, and an augmentation performed with a single additional fan (in the case of the fan assisted augmentation) or with a single synthetic jet ejector (in the case of the synthetic jet augmentation).
[0052] In the fan cooling only case, the fan was operated at 9000 rpm in order to maintain a chip temperature of 80° C. The reliability of the chip was 34 ppm and the reliability of the fan under these conditions was 58 ppm, thus giving a system reliability of 92 ppm and an expected life of 25,000 hours.
[0053] In the fan assisted augmentation, the addition of a second fan allowed both fans to be operated at 6000 rpm in order to maintain a chip temperature of 80° C. This improved fan reliability to 39 ppm, but gave rise to a system reliability of 112 ppm and an expected life of only 20,000 hours.
[0054] In the synthetic jet assisted augmentation, the addition of a synthetic jet ejector allowed the fan to be operated at 6000 rpm in order to maintain a chip temperature of 80° C. This not only improved fan reliability to 39 ppm, but gave rise to a system reliability of 83 ppm and increased the expected life of the system to 28,000 hours. These results thus demonstrate the improvements in system performance and reliability achievable with synthetic jet augmentation.
[0055] FIGS. 14 and 15 depict particular, non-limiting embodiments of synthetic jet ejectors that can be used in synthetic jet augmentation in accordance with the teachings herein. In the synthetic jet ejector 1401 depicted in FIG. 14 , a single synthetic jet actuator 1403 is equipped with a plurality of conduits 1405 from which synthetic jets are emitted. In the synthetic jet ejector 1501 depicted in FIG. 15 , a single synthetic jet actuator 1503 is equipped with a plurality of conduits 1505 , each of which is further divided into a plurality of sub-conduits 1507 from which synthetic jets are emitted.
[0056] The synthetic jet ejectors of FIGS. 14-15 may be utilized to create synthetic jets at large distances from their respective synthetic jet actuators. Thus, for example, tests have shown that conduits of up to 2 m in length may be utilized to produce synthetic jets. Hence, synthetic jet ejectors of the type depicted in FIGS. 14-15 may be utilized to allow a synthetic jet actuator to be placed anywhere in a system where room exists, while still allowing synthetic jets to be created locally at hot spots. This approach represents a significant improvement over conventional approaches such as fan-based thermal management systems, which require large flow rates at a single spot.
[0057] The above description of the present invention is illustrative, and is not intended to be limiting. It will thus be appreciated that various additions, substitutions and modifications may be made to the above described embodiments without departing from the scope of the present invention. Accordingly, the scope of the present invention should be construed in reference to the appended claims. | A computing device is provided which comprises (a) a chassis having an array of printed circuit boards (PCBs) disposed therein, wherein said chassis has a first wall with a first opening therein, and a second wall with a second opening therein, wherein each PCB is equipped with a microprocessor and a heat sink, and wherein each heat sink comprises a plurality of heat fins that define a plurality of longitudinal channels; (b) a fan which creates a fluidic flow that enters through said first opening and exits through said second opening, said fluidic flow being essentially parallel the longitudinal axes of said plurality of longitudinal channels; and (c) a synthetic jet ejector which directs at least one synthetic jet through at least one of said plurality of channels. | 6 |
BACKGROUND
[0001] The field of the disclosure relates generally to air management systems and, more particularly, to an integrated air management system having reduced weight and optimized performance.
[0002] At least some known aircraft air management systems (AMS) include supply sources for high-pressure (HP), low-pressure (LP). Typically, the HP and LP flows are supplied directly from a respective bleed port on an engine on the aircraft. Various pressure and flow requirements may not be met on some engines for all ranges of operation of the aircraft. For these cases, a mixed mode bleed may be supplied through a jet pump. The jet pump receives both HP and LP air flow, mixes the flows in selectable proportions and delivers the mixed mode bleed air to the AMS. Various pressure and flow requirements may not be met on some engines for all ranges of operation of the aircraft. Moreover, newer engines tend to have constrained space requirements that do not permit the use of standard architecture jet pump components and simply scaling the standard architecture jet pumps will not be able to mix the HP and LP flows adequately. Moreover, bleeding large quantities of highly compressed air from an engine compressor tends to reduce the efficiency and/or increase the specific fuel consumption of the engine. Such a tendency can affect the overall performance of the gas turbine engine associated with the compressor and/or the entire aircraft. In addition, the use of mixed mode jet pump operation provides air at temperatures/pressure closer to the aircraft needs, allowing for a smaller pre-cooler (heat exchanger), providing an additional weight savings for the aircraft.
BRIEF DESCRIPTION
[0003] In one embodiment, an AMS includes a jet pump assembly including a motive air inlet, a plurality of suction inlets, and a single outlet. The AMS also includes a supply piping arrangement including a conduit configured to channel relatively higher pressure air from a compressor to the motive air inlet, a conduit configured to channel relatively higher pressure air from the compressor to at least one of the plurality of suction inlets through a shutoff valve, and a conduit configured to channel relatively lower pressure air from the compressor to at least one of the plurality of suction inlets. The AMS further includes an outlet piping arrangement configured to channel outlet air from the jet pump assembly to a distribution system.
[0004] In another embodiment, a method of operating an integrated air management system (AMS) is provided. The AMS includes a supply system coupled to a compressor of a gas turbine engine and an air distribution system. The method includes generating a flow of distribution air using at least one of a flow of relatively higher pressure air and a flow of relatively lower pressure air in a jet pump assembly, channeling the flow of distribution air to the air distribution system, and controlling a relative flow of the relatively higher pressure air with respect to the flow of relatively lower pressure air to maintain an efficiency of the integrated AMS at a first efficiency level. The method further includes receiving a demand signal and controlling the relative flow of the relatively higher pressure air flow with respect to the flow of relatively lower pressure air to maintain an efficiency of the integrated AMS at a second efficiency level based on the received demand signal.
[0005] In yet another embodiment, an aircraft includes an air management system (AMS) that includes a jet pump assembly configured to operate in a plurality of selectable modes, each of the selectable modes selected using a demand signal from an engine, each of the plurality of selectable modes associated with an efficiency of operation of the AMS. The AMS also includes a an outlet piping arrangement coupled to an outlet of the jet pump assembly and an inlet piping arrangement configured to couple the jet pump assembly to a relatively higher pressure source of air and a relatively lower pressure source of air, the inlet piping arrangement including a plurality of controlled operation valves and configured to receive automatic command signals that command the operation of the plurality of controlled operation valves to align the inlet piping arrangement into the selectable modes.
DRAWINGS
[0006] These and other features, aspects, and advantages of the present disclosure will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:
[0007] FIG. 1 is a schematic illustration of an exemplary gas turbine engine in accordance with an example embodiment of the present disclosure.
[0008] FIG. 2 is a perspective view of an aircraft including a fuselage and a wing.
[0009] FIG. 3 is a three dimensional (3D) isometric piping view of an aircraft air management system (AMS) supply source.
[0010] FIG. 4 is a graph of engine bleed pressure at various engine power settings.
[0011] FIG. 5 is a graph of engine bleed temperature at various engine power settings.
[0012] FIG. 6 is a graph of engine specific fuel consumption (SFC) at various engine power settings.
[0013] FIG. 7 is a flow chart of a method of operating an integrated air management system (AMS) that includes a supply system coupled to a compressor of a gas turbine engine and an air distribution system.
[0014] Unless otherwise indicated, the drawings provided herein are meant to illustrate features of embodiments of this disclosure. These features are believed to be applicable in a wide variety of systems including one or more embodiments of this disclosure. As such, the drawings are not meant to include all conventional features known by those of ordinary skill in the art to be required for the practice of the embodiments disclosed herein.
DETAILED DESCRIPTION
[0015] In the following specification and the claims, reference will be made to a number of terms, which shall be defined to have the following meanings.
[0016] The singular forms “a”, “an”, and “the” include plural references unless the context clearly dictates otherwise.
[0017] “Optional” or “optionally” means that the subsequently described event or circumstance may or may not occur, and that the description includes instances where the event occurs and instances where it does not.
[0018] Approximating language, as used herein throughout the specification and claims, may be applied to modify any quantitative representation that could permissibly vary without resulting in a change in the basic function to which it is related. Accordingly, a value modified by a term or terms, such as “about”, “approximately”, and “substantially”, are not to be limited to the precise value specified. In at least some instances, the approximating language may correspond to the precision of an instrument for measuring the value. Here and throughout the specification and claims, range limitations may be combined and/or interchanged, such ranges are identified and include all the sub-ranges contained therein unless context or language indicates otherwise.
[0019] Embodiments of an Air Management System (AMS) as described herein provide air to aircraft system at various flow rates and pressures to fulfill the operational and environmental requirements of the aircraft. Such requirements define considerations of piping optimization for using a light weight and compact integrated AMS. In the example embodiment, one pump body and associated valves permits three operating modes: a) bleed air extraction from low-pressure (LP) port of a compressor only, b) bleed air extraction from a high-pressure (HP) port of the compressor only, and mixed bleed air extraction from the HP and LP ports. One set of downstream piping serves all three operating modes. The example embodiment include packaging benefits, such as, but, not limited to reduced weight, smaller bi-fi, and fuel-driven valves confined to the core fire-zone. The selected compressor bleed ports are also able to be optimized for an engine efficiency improvement. The cycle efficiency penalty for aircraft bleed is minimized by designing ports on the lowest compressor stage that meets aircraft bleed requirements. Typically, the set low port is based on pressure available to the turbine at an end-of-cruise (non-icing operation). The energy requirements for icing tend to drive LP ports into higher stages of the compressor. However, mixing the HP and LP flows simulates a variable intermediate stage port, allowing a lower port to be selected for efficiency while still providing capability in icing and increasing efficiency. The example embodiment facilitates covering gaps in the temperature/pressure profile where HP air is too hot and LP pressure is too low. The example embodiment provides for power management optimization based on a component and engine efficiency improvement. The HP pressure is regulated and is variable using a Jet Pump Shut Off Valve (JPSOV) and a downstream pressure sensor feedback to provide feedback for improved jet pump efficiency at each operational point. The JPSOV regulation strategy of constant pressure output reduces the contribution of HP flow at high power. Embodiments of the present disclosure also permit higher rated thrust at the same engine turbine temperatures as traditional designs. At low power, the regulated HP/LP pressure ratio increases, which results in greater HP flow contribution. In addition, the use of mixed mode jet pump operation provides air at temperatures/pressure closer to the aircraft demand, allowing for a smaller pre-cooler (heat exchanger), providing an additional weight savings for the aircraft.
[0020] FIG. 1 is a schematic illustration of an exemplary gas turbine engine 10 . Engine 10 includes a low pressure compressor 12 , a high pressure compressor 14 , and a combustor assembly 16 . Engine 10 also includes a high pressure turbine 18 , and a low pressure turbine 20 arranged in a serial, axial flow relationship. Compressor 12 and turbine 20 are coupled by a first shaft 21 , and compressor 14 and turbine 18 are coupled by a second shaft 22 .
[0021] During operation, air flows along a central axis 15 , and compressed air is supplied to high pressure compressor 14 . The highly compressed air is delivered to combustor 16 . Airflow (not shown in FIG. 1 ) from combustor 16 drives turbines 18 and 20 , and turbine 20 drives low pressure compressor 12 by way of shaft 21 . Gas turbine engine 10 also includes a fan containment case 40 .
[0022] FIG. 2 is a perspective view of an aircraft 100 including a fuselage 102 and a wing 104 . A gas turbine engine 106 is coupled to wing 104 and is configured to supply propulsive power to aircraft 100 and may be a source of auxiliary power to various systems of aircraft 100 . For example, gas turbine engine 106 may supply electrical power and pressurized air to the various systems. In one example, gas turbine engine 106 supplies pressurized air to an aircraft air management system (AMS) 108 . In various embodiments, gas turbine engine 106 supplies a relatively higher pressure air through a first high-pressure conduit 110 and relatively lower pressure air through a second low-pressure conduit 112 . In other embodiments, the relatively higher pressure air, the relatively lower pressure air, and a combination of the relatively higher pressure air and the relatively lower pressure air is generated proximate gas turbine engine 106 and channeled to AMS 108 through a single conduit, for example, first high-pressure conduit 110 or second low-pressure conduit 112 .
[0023] FIG. 3 is a three dimensional (3D) isometric piping view of an aircraft air management system (AMS) supply source 200 . AMS supply source 200 includes a high-pressure (HP) source, such as, but not limited to one or more compressor 10 th stage bleed ports 202 , low-pressure (LP) source, such as, but not limited to one or more compressor 4 th stage bleed ports 204 . Air from various combinations of ports 202 and 204 provide high-pressure, low-pressure, and mixed mode flows to a jet pump 205 , which is supplied through a jet pump outlet 207 to a downstream AMS. Typically, the HP and LP flows are supplied directly from bleed ports 202 and 204 from a respective engine. A mixed mode bleed is supplied through a jet pump 205 . Jet pump 205 receives both HP and LP air flow, mixes the flows in selectable proportions in a pre-mixing bowl 206 and delivers the mixed mode bleed air to the AMS through a mixing tube 209 . Upstream duct bends 211 promote a non-uniform flow field between the multiple inlets, promoting swirl in the low-pressure flows without the use of swirl vanes.
[0024] A jet pump shutoff valve (JPSOV) 208 modulates to supply high-pressure air to a throat 210 of jet pump 205 . A pressure sensor 213 between JPSOV 208 and throat 210 provides pressure feedback to control a position of JPSOV 208 to provide substantially constant selected pressure to throat. A controller 215 may be communicatively coupled to JPSOV 208 and pressure sensor 213 . Controller 215 may include a memory and a processor in communication so that instructions programmed in the memory control the processor to receive a pressure signal from pressure sensor 213 and a threshold value to generate a position command, which is transmitted to JPSOV 208 . A high-pressure shutoff valve (HPSOV) 212 opens and closes to supply high-pressure air from 10 th stage ports 202 to a first inlet 214 . Check valves 216 and 218 prevent back flow from 10 th stage ports 202 to 4 th stage bleed ports 204 .
[0025] AMS supply source 200 operates in three modes where outlet 207 is supplied from low-pressure 4 th stage bleed ports 204 , from high-pressure bleed ports 202 , and a mixed supply from both low-pressure 4 th stage bleed ports 204 and high-pressure bleed ports 202 . In a first mode, outlet 207 is supplied from low-pressure 4 th stage bleed ports 204 with both JPSOV 208 and HPSOV 212 in a closed position. In a second mode, outlet 207 is supplied from high-pressure bleed ports 202 with JPSOV 208 in a closed position and HPSOV 212 in an open position. A third mode is a jet pump mode where HPSOV 212 is in a closed position and JPSOV 208 is in an open position. When in the open position, JPSOV 208 modulates to adjust flow from a single leg of the high-pressure supply portion 220 of AMS supply source 200 .
[0026] A flow sensor 222 is configured to measure an amount of the extracted flow from the 10 th stage that is directed to AMS supply source 200 . The 10 th stage bleed measurement is used to maintain the engine operation according to a predetermined air management schedule. Bleeding air from the 10 th stage may affect other stages of the engine. A map of a range of 10 th stage flow rates is used to determine an impact for the various flow rates on the engine. The 10 th stage bleed flow rate is accounted for in thrust schemes and fielding schemes that affect the engine performance.
[0027] FIG. 4 is a graph 300 of engine bleed pressure at various engine power settings. Graph 300 includes an x-axis 302 graduated in units of net thrust of engine (lbf) 106 and a y-axis 304 graduated in units of bleed total pressure (psig). A trace 306 illustrates a lower stage pressure, such as a fourth stage pressure of engine 106 . A trace 308 illustrates an upper stage pressure, such as a tenth stage pressure of engine 106 . Traces 306 and 308 represent the bounds of supply pressure to jet pump 205 . A trace 310 illustrates a thrust versus bleed pressure curve for jet pump operation regulated to maintain approximately 225 psig pressure at throat 210 of jet pump 205 . A trace 312 illustrates a thrust versus bleed pressure curve for jet pump operation regulated to maintain approximately 200 psig pressure at throat 210 . A trace 314 illustrates a thrust versus bleed pressure curve for jet pump operation regulated to maintain approximately 175 psig pressure at throat 210 . A trace 316 illustrates a thrust versus bleed pressure curve for jet pump operation regulated to maintain approximately 150 psig pressure at throat 210 . A trace 318 illustrates a thrust versus bleed pressure curve for jet pump operation regulated to maintain approximately 125 psig pressure at throat 210 . A trace 320 illustrates a thrust versus bleed pressure curve for jet pump operation regulated to maintain approximately 100 psig pressure at throat 210 . A trace 322 illustrates a thrust versus bleed pressure curve for jet pump operation regulated to maintain approximately 75 psig pressure at throat 210 .
[0028] FIG. 5 is a graph 400 of engine bleed temperature at various engine power settings. Graph 400 includes an x-axis 402 graduated in units of net thrust of engine (lbf) 106 and a y-axis 404 graduated in units of bleed total temperature (° C.). A trace 406 illustrates a lower stage temperature, such as a fourth stage temperature of engine 106 . A trace 408 illustrates an upper stage temperature, such as a tenth stage temperature of engine 106 . Traces 406 and 408 represent the bounds of supply temperature to jet pump 205 . A trace 410 illustrates a thrust versus bleed temperature curve for jet pump operation regulated to maintain approximately 225 psig pressure at throat 210 of jet pump 205 . A trace 412 illustrates a thrust versus bleed temperature curve for jet pump operation regulated to maintain approximately 200 psig pressure at throat 210 . A trace 414 illustrates a thrust versus bleed temperature curve for jet pump operation regulated to maintain approximately 175 psig pressure at throat 210 . A trace 416 illustrates a thrust versus bleed temperature curve for jet pump operation regulated to maintain approximately 150 psig pressure at throat 210 . A trace 418 illustrates a thrust versus bleed temperature curve for jet pump operation regulated to maintain approximately 125 psig pressure at throat 210 . A trace 420 illustrates a thrust versus bleed temperature curve for jet pump operation regulated to maintain approximately 100 psig pressure at throat 210 . A trace 422 illustrates a thrust versus bleed temperature curve for jet pump operation regulated to maintain approximately 75 psig pressure at throat 210 .
[0029] FIG. 6 is a graph 500 of engine specific fuel consumption (SFC) at various engine power settings. Graph 500 includes an x-axis 502 graduated in units of net thrust of engine (lbf) 106 and a y-axis 504 graduated in units of specific fuel consumption (SFC) (lbm/hr/lbf). A trace 506 illustrates an engine SFC curve versus engine net thrust when using only a lower compressor stage air for AMS 108 , such as a fourth stage of compressor 12 of engine 106 . A trace 508 illustrates an engine SFC curve versus engine net thrust when using only an upper compressor stage air for AMS 108 , such as a tenth stage of compressor 12 . Traces 506 and 508 represent the bounds of SFC of engine 106 based on AMS demand. A trace 510 illustrates a thrust versus SFC curve for jet pump operation regulated to maintain approximately 225 psig pressure at throat 210 of jet pump 205 . A trace 512 illustrates a thrust versus SFC curve for jet pump operation regulated to maintain approximately 200 psig pressure at throat 210 . A trace 514 illustrates a thrust versus SFC curve for jet pump operation regulated to maintain approximately 175 psig pressure at throat 210 . A trace 516 illustrates a thrust versus SFC curve for jet pump operation regulated to maintain approximately 150 psig pressure at throat 210 . A trace 518 illustrates a thrust versus SFC curve for jet pump operation regulated to maintain approximately 125 psig pressure at throat 210 . A trace 520 illustrates a thrust versus SFC curve for jet pump operation regulated to maintain approximately 100 psig pressure at throat 210 . A trace 522 illustrates a thrust versus SFC curve for jet pump operation regulated to maintain approximately 75 psig pressure at throat 210 .
[0030] Traces 506 - 522 illustrate the benefit of jet pump 205 for improving SFC during operations that demand an output greater than that which only the fourth stage can provide but, that does not demand as much AMS output as the tenth stage can provide. These intermediate ranges are supplied by using tenth stage air to provide motive air to jet pump 205 while the fourth stage supplies air to the suction of jet pump 205 .
[0031] It can be seen that using different levels of intermediate air pressures from jet pump 205 , a SFC can be selected, which can aid engine 106 overall performance or performance during particular maneuvers.
[0032] FIG. 7 is a flow chart of a method 700 of operating an integrated air management system (AMS) that includes a supply system coupled to a compressor of a gas turbine engine and an air distribution system. In the example embodiment, method 700 includes generating 702 a flow of distribution air using at least one of a flow of relatively higher pressure air and a flow of relatively lower pressure air in a jet pump assembly, channeling 704 the flow of distribution air to the air distribution system, and controlling 706 a relative flow of the relatively higher pressure air with respect to the flow of relatively lower pressure air to maintain an efficiency of the integrated AMS at a first efficiency level. Method 700 also includes receiving 708 a demand signal and controlling 710 the relative flow of the relatively higher pressure air flow with respect to the flow of relatively lower pressure air to maintain an efficiency of the integrated AMS at a second efficiency level based on the received demand signal.
[0033] Method 700 optionally includes controlling the relative flow of the relatively higher pressure air flow with respect to the flow of relatively lower pressure air to maintain a predetermined temperature of the distribution air. Method 700 may also include generating a flow of distribution air using one of a first operating mode, a second operating mode, and a third operating mode, the first operating mode generates the flow of distribution air using the flow of relatively lower pressure air in the jet pump assembly, the second operating mode generates the flow of distribution air using the flow of relatively higher pressure air in the jet pump assembly, and the third operating mode generates the flow of distribution air using a mixed flow of relatively lower pressure air and of relatively higher pressure air. Additionally, method 700 may further include channeling the flow of relatively higher pressure air from a high pressure bleed port of the compressor to a suction inlet of the jet pump assembly. Optionally, method 700 may include modulating the flow of relatively higher pressure air using a modulating valve coupled between the high pressure bleed port of the compressor and a supply inlet of the jet pump assembly. Further, method 700 may include modulating the flow of relatively higher pressure air based on a pressure feedback from a pressure sensor positioned between the modulating valve and the supply inlet of the jet pump assembly. Method 700 may also include channeling the flow of relatively higher pressure air from at least one high pressure bleed port of the compressor to a supply inlet of the jet pump assembly and channeling the flow of relatively lower pressure air from at least one low pressure bleed port of the compressor to at least one suction inlet of the jet pump assembly. Optionally, method 700 may also include channeling the flow of relatively lower pressure air to a first suction inlet of the jet pump assembly and to a second suction inlet of the jet pump assembly, an opening of the first suction inlet of the jet pump assembly including a first area, an opening of the second suction inlet of the jet pump assembly including a second area, the first area being larger than the second area. Method 700 may also include channeling the flow of relatively lower pressure air to a first suction inlet of the jet pump assembly and to a second suction inlet of the jet pump assembly, the flow of relatively lower pressure air to first suction inlet of the jet pump assembly including a first velocity, the flow of relatively lower pressure air to the second suction inlet of the jet pump assembly including a second velocity, the first velocity being less than the second velocity.
[0034] Although specific features of various embodiments of the disclosure may be shown in some drawings and not in others, this is for convenience only. In accordance with the principles of the disclosure, any feature of a drawing may be referenced and/or claimed in combination with any feature of any other drawing.
[0035] This written description uses examples to disclose the embodiments, including the best mode, and also to enable any person skilled in the art to practice the embodiments, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the disclosure 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 method and system for an air management system (AMS) is provided. The AMS includes a jet pump assembly including a motive air inlet, a plurality of suction inlets, and a single outlet. The AMS also includes a supply piping arrangement including a conduit configured to channel relatively higher pressure air from a compressor to the motive air inlet, a conduit configured to channel relatively higher pressure air from the compressor to at least one of the plurality of suction inlets through a shutoff valve, and a conduit configured to channel relatively lower pressure air from the compressor to at least one of the plurality of suction inlets. The AMS further includes an outlet piping arrangement configured to channel outlet air from said jet pump assembly to a distribution system. A pressure regulation strategy of the motive jet pump flow allows optimization of engine fuel burn and/or thrust, depending on which is most important to the aircraft during any flight phase. | 8 |
This application claims priority under 35 USC §119(e)(1) of provisional application Nos. 60/070,223 filed Dec. 31, 1997.
CROSS-REFERENCE TO RELATED APPLICATION
The present application has some Figures in common with, but is not necessarily otherwise related to, the following applications, which have common ownership and common effective filing dates with the present application: “Fast Frame Readout Architecture for Array Sensors with Integrated Correlated Double Sampling System” Serial No. 60/070,083 filed Dec. 31, 1997; and “Sequential Correlated Doubling Sampling Technique for CMOS Area Array Sensors” Serial No. 60/070,082 filed Dec. 31, 1997, now U.S. Pat. No. 6,248,991; both of which are herein incorporated by reference.
BACKGROUND AND SUMMARY OF THE INVENTION
The present application relates to CMOS imagers.
Background: CMOS Imagers
For the past 20 years or so, the field of optical sensing has been dominated by the charged couple device (“CCD”). However, CCD sensors have a number of problems associated with their manufacture and use. CCD imagers require a special manufacturing process which is incompatible with standard CMOS processing. Thus CCD imagers cannot be integrated with other chips that provide necessary support functions, but require independent support chips to perform, for example, CCD control, A/D conversion, and signal processing. The operation of a CCD imager also requires multiple high voltage supplies varying from, e.g. 5V to 12V. The higher voltages produce higher power consumption for CCD devices. Consequently, costs for both the CCD image sensor and ultimately the system employing the sensor, remain high.
The recent advances in CMOS technology have opened the possibility of imagers offering significant improvements in functionality, power, and cost of, for example, digital video and still cameras. Advances in chip manufacturing processes and reductions in supply voltages have encouraged revisitation of CMOS technology for use in image sensors. The advent of sub-micron CMOS technology allows pixels which contain several FETs, and are circuits in their own right, to be comparable in size to those existing on commercial CCD imagers. Fabrication on standard CMOS process lines permits these imagers to be fully integrated with digital circuitry to create single-chip camera systems. A CMOS area array sensor (or CMOS imager) can be fabricated with other system functions, e.g. controller, A/D, signal processor, and DSP. Hence, the cost of the CMOS process is more economical than that of the CCD process. CMOS imagers can operate with a single low supply voltage, e.g. 3.3V or 5V. This provides lower power consumption than CCD imagers.
Background: Fixed Pattern Noise
One significant disadvantage with CMOS imagers has previously limited their widespread application—Fixed Pattern Noise (“FPN”). FPN is a built-in characteristic of X-Y addressable devices and is particularly an issue with any sort of CMOS imaging chips. FPN is noise that appears in a fixed pattern because the noise level is related to the position of the pixel in the array, the geometry of the column bus, and the proximity of other noise sources. (In addition, there is purely random noise not correlated to the pixel position, but due to inherent characteristics of the detector.) The effect of FPN is like viewing a scene through a window made of photo negatives. FPN occurs when process limitations produce device mismatches and/or non-uniformities of the sensor during fabrication on a wafer. FPN consists of both pixel FPN and column FPN. Each pixel circuit comprises at least a photodiode and a sensing transistor (operating as source-follower) as shown in FIG. 3 . Mismatches of the sensing transistor between pixels may produce different output levels for a given input optical signal. The variations of these output levels is called pixel FPN. Additionally, each column (or row) has separate read circuitry. Driver mismatches between different columns (or rows) produce column FPN. Most device mismatches are caused by threshold voltage (V T ) mismatches among CMOS transistors across the wafer.
A conventional solution for FPN suppression is to use a memory block to store the signal data for a whole frame and to subtract the FPN by sampling a reset voltage for the whole frame. The subtraction is done on a frame-by-frame basis which results in very slow frame rates.
Background: Correlated Double Sampling
Correlated Double Sampling (“CDS”) plays an important role in removing several kinds of noise in high-performance imaging systems. Basically, two samples of the sensor output are taken. First, a reference sample is taken that includes background noise and noise derived from a device mismatch. A second sample is taken of the background noise, device mismatch, and the data signal. Subtracting the two samples removes any noise which is common (or correlated) to both, leaving only the data signal. However, sensing the threshold voltage (V T ) of the sensing transistor, is a problem. CDS is discussed in greater detail in a paper by Chris Mangelsdorf, Analog Devices, Inc., 1996 IEEE International Solid-State Circuits Conference, and is hereby incorporated by reference.
Mismatch Effects of a Non-ideal Pixel Reset Switch
No solutions currently exist for suppressing FPN caused by the mismatch effects of an NMOS reset switch in CMOS imagers. In silicon fabrication, an NMOS switching device with minimum size is normally used as the reset switch in order to obtain minimum pixel size for good image resolution, and to minimize parasitic capacitances. Variations in the device threshold voltages, V T , and sizes of the NMOS switching devices when fabricated in a wafer can be a large source of FPN. The effects are similar to the FPN caused by the variations of pixel-sensing NMOS transistors in a CMOS imager, without a Sequential CDS implementation (“SCDS”).
Mismatch-Independent Reset Sensing for CMOS Imagers
The present application discloses a technique for suppressing fixed pattern noise derived from a pixel reset switch. The Mismatch Independent Reset Sensing (“MIRS”) technique disclosed in this application enables reset-switch sensing in SCDS or CDS architectures to be independent of NMOS switching device variations. This is achieved by ensuring that the reset switch always operates in its linear region when turned ON. Therefore, even if mismatch effects exist in an NMOS reset switching device, the mismatch effect will not produce FPN on the pixel readout.
An advantage is that the reset switch mismatch effects in a CMOS area array sensor will not produce FPN at the output by using MIRS technique. Another advantage is that the MIRS, together with the SCDS technique, can suppress FPN from {fraction (1/25)} to {fraction (1/20)} the level when not implementing the innovative technique. Therefore, wide-spread application of CMOS imagers can be realized by using the SCDS/MIRS technique. Another advantage is that the technique can be easily integrated with other CDS techniques. Another advantage is that the innovative method provides a fully-integrated and low-cost solution to where a single chip incorporates all the necessary digital circuits for the CMOS imager system.
BRIEF DESCRIPTION OF THE DRAWING
The disclosed inventions will be described with reference to the accompanying drawings, which show important sample embodiments of the invention, wherein:
FIG. 1 shows a first embodiment for suppressing FPN from a non-ideal reset switch.
FIG. 2 shows a second embodiment for suppressing FPN from a non-ideal reset switch.
FIG. 3 shows a typical pixel circuit configuration.
FIG. 4 shows an integrated circuit imaging chip using the innovative readout architecture.
FIG. 5 shows a camera using an integrated circuit imaging chip using with the innovative readout architecture.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The numerous innovative teachings of the present application will be described with particular reference to the presently preferred embodiment. However, it should be understood that this class of embodiments provides only a few examples of the many advantageous uses of the innovative teachings herein. In general, statements made in the specification of the present application do not necessarily delimit any of the various claimed inventions. Moreover, some statements may apply to some inventive features but not to others.
Conventional Pixel Sampling Using CDS
Two different types of sensors can be realized in CMOS technology. These are passive and active pixel sensors. The difference between these two types is that a passive pixel does not perform signal amplification whereas an active pixel does. A passive-pixel sensor is simply a photodiode (MOS or p-n junction diode) with a transistor that passes photoelectrically generated signal charge to an amplifier outside the pixel array. FIG. 3 shows a typical active-pixel sensor circuit. The gate of transistor N 1 is connected to a reset switch RES and the cathode of a photodiode PD. Initially, the reset switch RES is open and the voltage at node IN approximates the voltage generated by the photodiode, V PD . A finite charge exists at node IN which is dependent on both the capacitances of the photodiode PD and gate of the NMOS transistor N 1 . When select switch SEL is closed, the voltage at node IN is read from the pixel circuit, less a threshold voltage V T . When reset switch RES is closed, the voltage at node IN rises to approximately V dd . The voltage at node IN is again read from the pixel circuit. Subtracting the two samples removes any noise which is common (or correlated) to both, leaving only the data signal. However, this approach does not suppress the mismatch effect caused by a non-ideal reset switch RES since the switch is outside of the double-sampling path.
MIRS Technique: V RES below V dd
Two approaches to solving this problem are disclosed in this application. The basic concept of MIRS is to force the NMOS reset switching device RES to always operate in its linear region when it turns ON. FIG. 1 shows a first embodiment for suppressing FPN from a non-ideal reset switch. The drain of the transistor reset switch RES is connected to a reset voltage source, V RES , which is independent of V dd . Voltage V RES should be set less than V dd by at least one V T , the threshold voltage, (including backgate bias effect) plus delta(V T ) (the maximum V T variation for a given process), for all operational conditions (for example, a wide temperature range, bright-light sensing, and dark sensing).
Thus,
V RES <V dd −( V T +delta( V T )).
During normal switching operations, the gate of the reset transistor RES is switched between a low voltage and V dd to turn transistor RES OFF and ON, respectively. When the gate voltage of transistor RES is approximately V dd , transistor RES is operating in its linear region (the difference of V dd and V RES is at least one V T , which is sufficient to operate transistor RES in its linear region). In linear mode, the source or gate voltage of the pixel-sensing transistor N 1 can be pulled up to the transistor RES drain voltage, V RES . The drain voltage is equal to V RES , no matter what the fabricated size of transistor RES, or the associated V T voltage variation. Therefore, all pixel-sensing NMOS transistors N 1 in a CMOS imager are able to sense the exact same V RES voltage during the reset phase, regardless of the wide variations in threshold voltages inherent across the large number of reset switches fabricated in the pixel circuits of the imager. Therefore the mismatch effect of the reset switching transistor RES is significantly reduced and hence FPN on the pixel readout is also significantly reduced.
MIRS Technique: Reset Switch Gate Voltage V gh Above V dd
FIG. 2 shows a second embodiment for suppressing FPN from a non-ideal reset switch. This approach connects the drain of the reset switching transistor RES to V dd (which is also connected to the drain of pixel-sensing transistor N 1 ). To ensure that the reset transistor RES operates in its linear region, the gate voltage V g of transistor RES is set higher than the V dd ; at least one V T (including backgate bias effect) plus delta(V T ) (the maximum V T variation for a given process), for all operational conditions (for example, a wide temperature range, bright-light sensing, and dark sensing). Thus the higher gate voltage, V gh , of the reset transistor RES is derived as follows,
V gh >V dd +( V T +delta( V T )).
To eliminate the need for another voltage supply for such an implementation, a charge pump circuit 200 is added to obtain the higher gate voltage level, V gh . A level-shift circuit 204 is connected between the charge pump 200 and pixel circuits 204 to increase the input gate voltage level of transistor RES from V dd to V gh . With this implementation, all pixel-sensing transistors N 1 in a CMOS imager are able to sense the exact same V dd voltage during the reset phase. Therefore the mismatch effect of the reset transistor RES will not produce FPN during readout of the pixel.
In the first approach, the reset voltage V RES is derived independently of the supply voltage V dd , and consequently, an additional line is needed for the pixel circuit. Therefore the area of the pixel in the first approach is slightly larger than the area of the pixel in the second approach. Hence the optical fill factor (the percentage of area in the array actually used for sensing) in the first approach will be smaller than that in the second approach for pixels of equal size.
In the second approach, both the charge pump 200 and level shift 204 circuits are implemented outside of the pixel circuit. Therefore a higher optical fill factor can be achieved than that of the first approach. Additionally, the charge pump circuit 200 may not be required in a dual 3.3V/5V power supply CMOS process. For such a process, the higher gate voltage, V gh , can be set directly to be 5V while the V dd is 3.3V.
Imaging Chip
FIG. 4 shows an imager chip comprising the innovative sampling architecture. The chip 400 incorporates a row select circuitry 404 and column select circuitry 402 to read the array sensor 401 . The output circuitry 403 receives pixel data from the column circuitry 402 and presents it to the output terminal OUT. Additional support circuitry may be fabricated in the peripheral region 405 . The chip 400 also has connections for supply voltage VDD, ground GND, and clocking signals CLOCK.
Camera Imaging System
FIG. 5 shows a camera using an integrated circuit imaging chip using with the innovative readout architecture. The camera 500 has a lens 501 which focuses an image onto the image sensor chip 502 . A processor 503 receives the data from the image chip 503 and sends it to a storage and output system 504 .
According to a disclosed class of innovative embodiments, there is provided: A method for operating a pixel circuit in a photosensing integrated circuit, comprising the steps of: turning on a reset transistor, using a reset gate voltage which is more in magnitude than any source/drain voltage of said reset transistor by a value of at least the sum of one threshold voltage plus the maximum threshold variation of the given process; and, after turning off said reset transistor, allowing a photosensing device to apply a illumination-dependent current to one of said source/drain terminals of a sensing transistor for a desired integration time; and thereafter sensing the voltage on said one source/drain terminal of said reset transistor.
According to another disclosed class of innovative embodiments, there is provided: A method for operating a photosensing device, comprising the steps of: providing a first supply voltage to a reset transistor, and turning on said reset transistor with a reset gate voltage which is approximately equal to a second supply voltage which exceeds in magnitude said first supply voltage; wherein said first supply voltage is always less in magnitude than said second supply voltage by at least the sum of one threshold voltage plus the maximum threshold variation of the given process; and wherein said reset transistor is connected to apply an initial voltage, which is precisely equal to said first supply voltage, regardless of the threshold voltage of said reset transistor, to the gate of a sensing transistor; and allowing a photosensing device to apply a illumination-dependent current to said gate of said sensing transistor for a desired integration time; and sensing current passed by said sensing transistor.
According to another disclosed class of innovative embodiments, there is provided: A pixel circuit, comprising: a photosensing subcircuit; and a plurality of active devices per said pixel circuit, comprising a reset transistor, a sensing transistor, and a selecting transistor; wherein said reset and sensing transistors receive first and second supply voltages, respectively; wherein said reset transistor intermittently receives a reset gate voltage which is equal to said second supply voltage; wherein said first supply voltage is always less in magnitude than said second supply voltage by at least the sum of one threshold voltage plus the maximum threshold variation of the given process; wherein said reset circuit operates in either a linear mode or an off mode, in dependence on said reset gate voltage; wherein said selecting transistor switches to either select a photosensing voltage or said first supply voltage.
According to another disclosed class of innovative embodiments, there is provided: A photosensing imaging system, comprising:a focusing element; an integrated imager circuit, comprising: a plurality of pixel circuits comprising active devices; said active devices comprising a reset transistor, a sensing transistor, and a selecting transistor; wherein said reset and sensing transistors receive first and second supply voltages, respectively; wherein said reset transistor intermittently receives a reset gate voltage which is equal to said second supply voltage; wherein said first supply voltage is always less in magnitude than said second supply voltage by at least the sum of one threshold voltage plus the maximum threshold variation of the given process; wherein said reset circuit operates in either a linear mode or an off mode, in dependence on said reset gate voltage; wherein said selecting transistor switches to either select a photosensing voltage or said first supply voltage; and pixel readout circuitry; a processor connected to control said imager; and a storage medium for receiving and storing data from said imager.
According to another disclosed class of innovative embodiments, there is provided: A pixel circuit, comprising: a photosensing subcircuit; and a plurality of active devices per said pixel circuit, comprising a reset transistor, a sensing transistor, and a selecting transistor; wherein said reset and sensing transistors receive a common supply voltage; wherein said reset transistor turns on with a reset gate voltage which exceeds said common supply voltage in magnitude by at least the sum of one threshold voltage plus the maximum threshold variation of the given process; wherein said reset transistor operates in either a linear mode or an off mode, in dependence on said reset gate voltage; wherein said selecting transistor switches to select either a photosensing voltage or said common supply voltage.
Modifications and Variations
As will be recognized by those skilled in the art, the innovative concepts described in the present application can be modified and varied over a tremendous range of applications, and accordingly the scope of patented subject matter is not limited by any of the specific exemplary teachings given.
For example, as will be obvious to those of ordinary skill in the art, other circuit elements can be added to, or substituted into, the specific circuit topologies shown.
For another example, within the constraints well-known to those of ordinary skill, nonlinear devices can be added in series with (or used to replace) resistors, to increase the impedance of load devices.
For another example, within the constraints well-known to those of ordinary skill, a variety of well-known current mirror configurations can be substituted for those shown.
For another example, within the constraints well-known to those of ordinary skill, a variety of well-known amplifier configurations can be substituted for those shown.
For another example, within the constraints well-known to those of ordinary skill, the innovative technique can be used in reduced voltage array architectures. | Two methods for suppressing the fixed pattern noise effects of a pixel reset switch by ensuring that the reset NMOS device operates in its linear region. The first approach uses a separate reset switch supply voltage, V RES , set to at least one threshold voltage below the sensing switch supply voltage, V dd . The second approach uses a charge pump and level shifter to push the reset gate voltage at least one threshold voltage higher than a supply voltage common to both the reset and sense transistors. | 7 |
CROSS-REFERENCE TO RELATED APPLICATION
This application is a continuation of U.S. patent application Ser. No. 12/551,664, filed on Sep. 1, 2009, which is a continuation of International Application No. PCT/CN2009/070517, filed on Feb. 24, 2009. The International Application claims priority to Chinese Patent Application No. 200810065734.2, filed on Feb. 28, 2008. The aforementioned patent applications are hereby incorporated by reference in their entireties.
FIELD OF THE INVENTION
The present invention relates to network communications, and in particular, to a method and apparatus for crosstalk channel estimation.
BACKGROUND OF THE INVENTION
Digital Subscriber Line (DSL) is a data transmission technology using telephone twisted pairs as the transmission medium. xDSL is a combination of DSL technologies including High-speed Digital Subscriber Line (HDSL), Single-pair High-Speed Digital Subscriber Line (SHDSL), and Asymmetrical Digital Subscriber Line (ADSL). SHDSL is based on baseband transmission. Other xDSL technologies, which are based on passband transmission and use the Frequency-Division Multiplexing (FDM) technology, may coexist with Plain Old Telephone Service (POTS) in the same twisted pairs.
As higher and higher bands are used by xDSL based on passband transmission, the highband crosstalk has become a severe problem. FIG. 1 shows a method for solving the crosstalk between xDSL lines by using a Vectored Digital Subscriber Line (Vectored-DSL) technology in the prior art. In the downlink direction, x indicates signal vectors sent by Nx1 coordinated transceiver devices such as a Digital Subscriber Line Access Multiplexer (DSLAM); y indicates signal vectors received by Nx1 opposite devices such as a subscriber-side device; and n indicates Nx1 noise vectors. The following channel transmission matrix indicates a shared channel:
H
=
[
h
11
h
12
⋯
h
1
M
h
21
h
22
⋯
h
2
M
⋮
⋮
⋱
⋮
h
N
1
h
N
2
⋯
h
NN
]
h ij (1≦i≦N,1≦j≦N) indicates a crosstalk transfer function of pair j to pair i; h ii (1≦i≦N) indicates the channel transfer function of pair i; and N indicates the number of pairs, that is, the number of subscribers. If a vector pre-encoder (represented by W) is used in a coordinated transceiver device, the signal vectors that an opposite device receives are calculated according to the following formula:
{tilde over (y)}=HWx+n
If the vector pre-encoder can make HW a diagonal matrix, for example, diag(H), the crosstalk may be cancelled. To cancel the crosstalk, channel estimation needs to be performed to obtain a channel transmission matrix.
While developing the present invention, the inventor found that signal errors are used to estimate channels in the prior art and devices are required to provide signal errors. Many devices running on a network, however, do not support this function. As a result, signal errors are not available for channel estimation and thus the crosstalk cannot be cancelled.
SUMMARY OF THE INVENTION
Embodiments of the present invention provide a method and apparatus for crosstalk channel estimation based on a measured signal-to-noise (SNR) of a loaded line.
One embodiment of the present invention provides a method for crosstalk channel estimation, including: loading, on a newly added line K, a combination of K−1 signals sent on lines 1 to K−1; obtaining a measured a signal-to-noise ratio (SNR) of the line K loaded with the combination of the K−1 signals sent on the lines 1 to K−1; and calculating crosstalk channels of the line K according to K−1 combination coefficients of the K−1 signals sent on the lines 1 to K−1 and the measured SNR.
Another embodiment of the present invention provides an apparatus comprising a transceiver configured to: load, on a newly added line K, a combination of K−1 signals sent on lines 1 to K−1; obtain a measured signal-to-noise ratio (SNR) of the line K loaded with the combination of the K−1 signals sent on the lines 1 to K−1; and calculate crosstalk channels of the line K according to K−1 combination coefficients of the K−1 signals sent on the lines 1 to K−1 and the measured SNR.
Yet another embodiment of the present invention provides a method for crosstalk channel estimation, comprising: receiving, at a transceiver corresponding to a newly added line K, a signal comprising a combination of K−1 signals sent on lines 1 to K−1; obtaining, at the transceiver, a signal-to-noise ratio (SNR) of the line K in response to the reception of the signal; and calculating, at the transceiver, crosstalk channels of the line K according to K−1 combination coefficients associated with the K−1 signals sent on the lines 1 to K−1 and the SNR.
A further embodiment of the present invention provides an apparatus comprising a transceiver configured to: receive, on a newly added line K, a signal comprising a combination of K−1 signals sent on lines 1 to K−1; obtain a signal-to-noise ratio (SNR) of the line K in response to the reception of the signal; and calculate crosstalk channels of the line K according to K−1 combination coefficients associated with the K−1 signals sent on the lines 1 to K−1 and the SNR.
The benefits of at least some embodiments of the present invention may include the following: no devices need to be redesigned (e.g., to provide signal errors); the measurement time is short; the precision is high; and the robustness is good.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a method for solving the crosstalk between xDSL lines by using a vectored-DSL technology in the prior art;
FIG. 2 shows a method for channel estimation in a first embodiment of the present invention;
FIG. 3 shows a system for channel estimation in a second embodiment of the present invention;
FIG. 4 shows a structure of a loading unit of a coordinated transceiver device in the second embodiment of the present invention;
FIG. 5 shows a system for channel estimation in a third embodiment of the present invention; and
FIG. 6 shows a structure of the loading unit of the coordinated transceiver device in the third embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention may be used to estimate crosstalk channels when new subscribers get online and may be further used to trace crosstalk channels. The following describes the present invention with an example of adding a new subscriber to a vector group. Suppose that there are K−1 lines in a vector group. When line K needs to be added to the vector group, the crosstalk between line K and other K−1 lines may be estimated respectively according to the SNR measured on line K.
FIG. 2 shows a method for channel estimation in a first embodiment of the present invention. The method includes the following steps:
Step 101 : The combination of signals sent on other lines is loaded over a line of a channel.
In this step, the coordinated transceiver device loads the combination of all or part of signals sent on line 1 to line K−1 over a sub-band in the downlink direction of line K. In this way, the lines whose signals are loaded and the lines that cause crosstalk to line K may be estimated. Various sub-bands are processed concurrently.
The embodiment describes how to load the combination of all signals sent on line 1 to line K−1. Suppose that the SNR of line K needs to be measured for N times, each lasting L symbols, and that other K−1 lines already enter the show-time state. If the signal to be sent on line i at the 1 th symbol during SNR measurement n is s i (n) (l), the signal actually sent on the line is x i (n) (l). When line K is added to the vector group, other lines continue to send original signals. In this case,
x i (n) ( l )= s i (n) ( l ),∀ i<K.
After the combination of signals sent on line 1 to line K−1 are added to the signals sent on line K, the signals sent on line K may be calculated according to the following formula:
x
K
(
n
)
(
l
)
=
s
K
(
n
)
(
l
)
+
ɛ
∑
i
=
1
K
-
1
z
i
(
n
)
s
i
(
n
)
(
l
)
.
where, z i (n) indicates the combination coefficient of line i during SNR measurement n and meets the following condition:
∑
i
=
1
K
-
1
|
z
i
(
n
)
|
2
=
1.
In an exemplary embodiment, the quadratic sum of the absolute value of the combination coefficient is 1 but may be any other value.
ε indicates a step, which is designed to avoid extra bit errors on line K due to the loaded signals. In this embodiment, the SNR tolerance at the receive end of line K must not be less than zero after the loaded signals are included. In general, the SNR tolerance of a line is 6 dB. For safety, the SNR at the receive end of line K after signal loading should not exceed 3.5 dB. In this embodiment, to meet the preceding requirements, ε is set according to the following formula:
ɛ
=
min
i
1
2
1
SNR
K
(
0
)
σ
K
σ
i
,
In the preceding formula, σ i 2 indicates the transmit power of line i (the coordinated transceiver device has known the transmit power of each line) and SNR K (0) indicates the SNR at the receive end of line K when no signals are loaded.
Step 102 : The SNR of the loaded line is measured.
In this step, the opposite device measures the SNR of the same sub-band in the downlink direction of line K. The SNR is directly measured.
Step 3 : Crosstalk channels of the loaded line are calculated according to the combination coefficient of signals sent on other lines and the measured SNR.
In this step, the coordinated transceiver device calculates the crosstalk channels of line K according to the returned SNR after line K is loaded from the opposite device and the combination coefficient of signals sent on other lines; or the coordinated transceiver device sends the combination coefficient of signals sent on other lines to the opposite device and the opposite device calculates the crosstalk channels of line K according to the measured SNR after line K is loaded and the received combination coefficient.
The deduction process of calculating the crosstalk channels of the loaded line is as follows:
According to the formula for calculating the signals sent after line K is loaded in step 101 , the signals received by the opposite device of line K are as follows:
y
k
(
n
)
(
l
)
=
∑
i
=
1
K
h
K
,
i
x
i
(
n
)
(
l
)
+
w
K
(
n
)
(
l
)
=
h
K
,
K
s
K
(
n
)
(
l
)
+
∑
i
=
1`
K
-
1
(
h
K
,
i
+
ɛ
z
i
(
n
)
h
K
,
K
)
s
i
(
n
)
(
l
)
+
w
K
(
n
)
(
l
)
The received signal power is as follows:
signal
K
=
1
L
∑
l
=
1
L
|
h
K
,
K
s
K
(
n
)
(
l
)
|
2
≈
|
h
K
,
K
|
2
σ
K
2
The received noise power is as follows:
noise
K
=
1
L
∑
l
=
1
L
|
y
K
(
n
)
(
l
)
-
h
K
,
K
s
K
(
n
)
(
l
)
|
2
≈
∑
i
=
1
K
-
1
|
h
K
,
i
+
ɛ
z
i
(
n
)
h
K
,
K
|
2
+
σ
i
2
+
σ
W
K
2
,
where, σ W K 2 , indicates the power of the background noise.
According to the preceding two formulas, when the transmit power of each line is the same, that is, σ i 2 =σ K 2 , the SNR measured by the opposite device of line K may be represented by the following formula:
1
SNR
K
(
n
)
=
noise
K
signal
K
≈
1
σ
K
2
(
∑
i
=
1
K
-
1
|
h
K
,
i
h
K
,
K
σ
i
+
ɛ
z
i
(
n
)
σ
i
|
2
+
σ
W
K
2
|
h
K
,
K
|
2
)
=
∑
i
=
1
K
-
1
|
h
K
,
i
h
K
,
K
+
ɛ
z
i
(
n
)
|
2
+
σ
W
K
2
|
h
K
,
K
|
2
σ
K
2
=
||
a
_
+
ɛ
b
_
(
n
)
||
2
+
σ
W
K
2
|
h
K
,
K
|
2
σ
K
2
In the case of σ i 2 =σ K 2 , the step is as follows:
ɛ
=
min
i
1
2
1
SNR
K
(
0
)
,
Supposing ā=[ā 1 . . . ā K-1 ] T , b (n) =[ b 1 (n) . . . b K-1 (n) ] T ,
a _ i = h K , i h K , K ,
and b i (n) =z i (n) , then according to the Pythagorean Proposition,
∥ā+ε b (n) ∥ 2 =∥ā∥ 2 +∥ε b (n) ∥ 2 +2 εRe{ b (n)H ā}
If ā and b (n) are decomposed into a real part and an imaginary part respectively, that is, a R,i =Re{ā i }, a I,i =Im{ā i }, b R,i (n) =Re{ b i (n) }, and b I,i (n) =Im{ b i (n) }, then
Re
{
b
_
(
n
)
H
a
_
}
=
∑
i
=
1
K
-
1
[
a
R
,
i
b
R
,
i
(
n
)
+
a
I
,
i
b
I
,
i
(
n
)
]
=
b
(
n
)
H
a
,
where, a=[a R,1 . . . a R,K-1 a I,1 . . . a I,K-1 ] T , and b (n) =[b R,1 (n) . . . b R,K-1 (n) b I,1 (n) . . . b I,K-1 (n) ] T .
For convenience, suppose a i =[a] i and b i (n) =[b (n) ] i . According to ∥ā+ε b (n) ∥ 2 =∥ā∥ 2 +∥ε b (n) ∥ 2 +2εRe{ b (n)H ā} and
Re { b _ ( n ) H a _ } = ∑ i = 1 K - 1 [ a R , i b R , i ( n ) + a I , i b I , i ( n ) ] = b ( n ) H a , , ∥ā+ε b (n) ∥ 2 =∥ā∥ 2 +∥ε b (n) ∥ 2 +2 εb (n)H a
According to the preceding formula and the SNR expression,
||
a
_
||
2
+
||
ɛ
b
_
(
n
)
||
2
+
2
ɛ
b
(
n
)
H
a
+
σ
W
K
2
|
h
K
,
K
|
2
σ
K
2
=
1
SNR
K
(
n
)
Therefore,
ɛ
b
(
n
)
H
a
+
1
2
||
a
_
||
2
+
1
2
σ
W
K
2
|
h
K
,
K
|
2
σ
K
2
=
1
2
1
SNR
K
(
n
)
-
1
2
||
ɛ
b
_
(
n
)
||
2
Due to b i (n) =z i (n) ,
ɛ
b
(
n
)
H
a
+
1
2
||
a
_
||
2
+
1
2
σ
W
K
2
|
h
K
,
K
|
2
σ
K
2
=
1
2
1
SNR
K
(
n
)
-
1
2
ɛ
2
∑
i
=
1
K
-
1
|
z
i
(
n
)
|
2
Supposing
c ( n ) = 1 2 1 SNR K ( n ) - 1 2 ɛ 2 ∑ i = 1 K - 1 | z i ( n ) | 2 ,
then
ɛ
b
(
n
)
H
a
+
1
2
||
a
_
||
2
+
1
2
σ
W
K
2
|
h
K
,
K
|
2
σ
K
2
=
c
(
n
)
,
∀
n
An M×N matrix P is defined, where p m,n =[P] m,n meets the following condition:
∑
n
=
1
N
p
m
,
n
=
0
,
∀
m
P is used as the combination matrix of the SNR. Then,
Σ
n
p
m
,
n
c
(
n
)
=
ɛ
Σ
n
p
m
,
n
b
(
n
)
H
a
+
(
1
2
||
a
_
||
2
+
1
2
σ
W
K
2
|
h
K
,
K
|
2
σ
K
2
)
Σ
n
p
m
,
n
,
∀
m
Due to
∑
n
=
1
N
p
m
,
n
=
0
,
∀
m
,
Σ
n
p
m
,
n
c
(
n
)
=
ɛ
Σ
n
p
m
,
n
b
(
n
)
H
a
,
∀
m
A formula in the preceding format is available for each n. Combine all these formulas into a matrix. Then,
P
[
c
(
1
)
⋮
c
(
N
)
]
=
ɛ
P
[
b
(
1
)
H
⋮
b
(
N
)
H
]
a
Supposing c=[c (1) . . . c (N) ] T and B=[b (1) . . . b (N) ] H , then
ε PBa=Pc
According to the preceding formula, the least square solution of a is as follows:
a=ε −1 pinv( PB ) Pc,
where, pinv(.) indicates a pseudo-inverse operation.
After the value of a is obtained, the crosstalk channels normalized by direct channels may be obtained according to
a _ i = h K , i h K , K
and a=[a R,1 . . . a R,K-1 a I,1 . . . a I,K-1 ] T .
The obtained crosstalk channels are represented by the following formula:
h
K
,
i
h
K
,
K
=
a
i
+
ja
K
-
1
+
i
According to the preceding deduction, the specific steps of calculating crosstalk channels are: selecting a proper combination matrix and perform calculation according to G=pinv(PB)P and the combination coefficient of signals sent on each line; performing calculation according to
c ( n ) = 1 2 1 SNR K ( n ) - 1 2 ɛ 2 ∑ i = 1 K - 1 | z i ( n ) | 2 ,
the combination coefficient of signals sent on each line, and the measured SNR; performing calculation according to a=ε −1 Gc and the preceding calculation results; and calculating the crosstalk channels normalized by direct channels according to
h
K
,
i
h
K
,
K
=
a
i
+
j
a
K
-
1
+
i
,
∀
i
.
When the transmit power of each line is different, the SNR measured by the opposite device of line K may be represented by the following formula:
1
SNR
K
(
n
)
=
noise
K
signal
K
≈
1
σ
K
2
(
∑
i
=
1
K
-
1
h
K
,
i
h
K
,
K
σ
i
+
ɛ
z
i
(
n
)
σ
i
2
+
σ
W
K
2
h
K
,
K
2
)
=
1
σ
K
2
(
a
_
+
ɛ
b
_
(
n
)
2
+
σ
W
K
2
h
K
,
K
2
)
,
Supposing ā=[ā 1 . . . ā K-1 ] T , b (n) =[ b 1 (n) . . . b K-1 ] T ,
a _ i = h K , i h K , K σ i ,
and b i (n) =z i (n) σ i , according to the Pythagorean Proposition,
∥ā+ε b (n) ∥ 2 =∥ā∥ 2 +∥ε b (n) ∥ 2 +2 εRe{ b (n)H ā}
If ā and b (n) are decomposed into a real part and an imaginary part respectively, that is, a R,i =Re{ā i }, a I,i =Im{ā i }, b R,i (n) =Re{ b i (n) }, and b I,i (n) =Im{ b i (n) }, then
Re
{
b
_
(
n
)
H
a
_
}
=
∑
i
=
1
K
-
1
[
a
R
,
i
b
R
,
i
(
n
)
+
a
I
,
i
b
I
,
i
(
n
)
]
=
b
(
n
)
H
a
,
where, a=[a R,1 . . . a R,K-1 a I,1 . . . a I,K-1 ] T , and b (n) =[b R,1 (n) . . . b R,K-1 (n) b I,1 (n) . . . b I,K-1 (n) ] T .
For convenience, suppose a i =[a] i and b i (n) =[b (n) ] i . According to ∥ā+ε b (n) ∥ 2 =∥ā∥ 2 +∥ε b (n) ∥ 2 +2εRe{ b (n)H ā} and
Re { b _ ( n ) H a _ } = ∑ i = 1 K - 1 [ a R , i b R , i ( n ) + a I , i b I , i ( n ) ] , = b ( n ) H a , ∥ā+ε b (n) ∥ 2 =∥ā∥ 2 +∥ε b (n) ∥ 2 +2 εb (n)H a
According to the preceding formula and the SNR expression,
a
_
2
+
ɛ
b
_
(
n
)
2
-
2
ɛ
b
(
n
)
H
a
+
σ
W
K
2
h
K
,
K
2
=
σ
K
2
SNR
K
(
n
)
Therefore,
ɛ
b
(
n
)
H
a
+
1
2
a
_
2
+
1
2
σ
W
K
2
h
K
,
K
2
=
1
2
σ
K
2
SNR
K
(
n
)
-
1
2
ɛ
b
_
(
n
)
2
Due to b i (n) =z i (n) ,
ɛ
b
(
n
)
H
a
+
1
2
a
_
2
+
1
2
σ
W
K
2
h
K
,
K
2
=
1
2
σ
K
2
SNR
K
(
n
)
-
1
2
ɛ
2
∑
i
=
1
K
-
1
z
i
(
n
)
2
σ
i
2
Supposing
c ( n ) = 1 2 σ K 2 SNR K ( n ) - 1 2 ɛ 2 ∑ i = 1 K - 1 z i ( n ) 2 σ i 2 ,
then
ɛ
b
(
n
)
H
a
+
1
2
a
_
2
+
1
2
σ
W
K
2
h
K
,
K
2
=
c
(
n
)
,
∀
n
An M×N matrix P is defined, where p m,n =[P] m,n meets the following condition:
∑
n
=
1
N
p
m
,
n
=
0
,
∀
m
P is used as the combination matrix of the SNR. Then
∑
n
p
m
,
n
c
(
n
)
=
ɛ
∑
n
p
m
,
n
b
(
n
)
H
a
+
(
1
2
a
_
2
+
1
2
σ
W
K
2
h
K
,
K
2
)
∑
n
p
m
,
n
,
∀
m
Due to
∑
n
=
1
N
p
m
,
n
=
0
,
∀
m
,
∑
n
p
m
,
n
c
(
n
)
=
ɛ
∑
n
p
m
,
n
b
(
n
)
H
a
,
∀
m
A formula in the preceding format is available for each n. Combine all these formulas into a matrix. Then
P
[
c
(
1
)
⋮
c
(
N
)
]
=
ɛ
P
[
b
(
1
)
H
⋮
b
(
N
)
H
]
a
Supposing c=[c (1) . . . c (N) ] T and B=[b (1) . . . b (N) ] H , then
ε PBa=Pc
According to the preceding formula, the least square solution of a is as follows:
a=ε −1 pinv( PB ) Pc,
where, pinv(.) indicates a pseudo-inverse operation.
After the value of a is obtained, the crosstalk channels normalized by direct channels may be obtained according to
a _ i = h K , i h K , K σ i ,
and a=[a R,1 . . . a R,K-1 a I,1 . . . a I,K-1 ] T . The obtained crosstalk channels are represented by the following formula:
h
K
,
i
h
K
,
K
=
1
σ
i
(
a
i
+
j
a
K
-
1
+
i
)
,
According to the preceding deduction, the specific steps of calculating crosstalk channels are as follows: selecting a proper combination matrix and perform calculation according to G=pinv(PB)P, the transmit power of each line, and the combination coefficient of signals sent on each line; performing calculation according to
c ( n ) = 1 2 σ K 2 SNR K ( n ) - 1 2 ɛ 2 ∑ i = 1 K - 1 z i ( n ) 2 σ i 2 ,
the transmit power of each line, the combination coefficient of signals sent on each line, and the measured SNR; performing calculation according to a=ε −1 Gc and the preceding calculation results; and calculating the crosstalk channels normalized by direct channels according to
h
K
,
i
h
K
,
K
=
(
a
i
+
j
a
K
-
1
+
i
)
/
σ
i
,
∀
i
.
Matrixes P and B may be selected in advance so as to realize optimal performance in most cases. Particularly, the following selections are required:
The normalized coefficient of discrete cosine transform is defined as follows:
u
n
,
m
=
{
2
N
cos
(
π
(
n
+
0.5
)
m
N
)
t
>
1
,
n
>
1
,
1
N
otherwise
The preceding coefficient is converted into a matrix and the direct current component is deleted from the first row. Then
U
=
[
u
2
,
1
…
u
2
,
N
⋮
⋱
⋮
u
2
K
-
1
,
1
…
u
2
K
-
1
,
N
]
U H is selected as the probe signal matrix, that is, B=U H . Thus, B =U row 1:K-1 H +jU row K:2(K-1) H . Suppose the combination matrix of the SNR is P=U. On the one hand, this matrix may ensure a minimum channel estimation error when the returned SNR is affected. On the other hand, this matrix may avoid calculating the pseudo-inversion of the product of matrixes P and B. In an algorithm, to reduce the operation complicity, matrix G may be directly obtained through matrix P, as shown in the following formula:
G
=
pinv
(
PB
)
P
=
pinv
(
UU
H
)
P
=
P
In addition, if the number of subscribers is 2 to the power of n, the Walsh-Hadamard sequence may be selected to generate matrix B. The Walsh-Hadamard sequence includes positive 1 and negative 1. Thus, multiplication operations during calculation may be replaced by simple addition and subtraction operations. For any matrix B that meets the requirements in the method, the channel matrix may be correctly calculated. The method is not limited to the preceding selection methods.
Different combination coefficients are used and steps 101 and 102 are repeated for at least 2K−1 times to calculate the crosstalk of other K−1 lines to line K. The times of repeating steps 101 and 102 depends on the number of other loaded lines, that is, the number of crosstalk channels to be measured.
The preceding process may be repeated for multiple times to continuously update crosstalk channels so as to improve the precision or trace lines.
In addition, according to the calculated crosstalk channels, a similar crosstalk cancellation and compensation filter may be designed, as shown in the following formula:
F
=
I
K
-
offdiag
(
[
h
1
,
1
h
1
,
1
…
h
1
,
K
h
1
,
1
⋮
⋱
⋮
h
K
,
1
h
K
,
K
…
h
K
,
K
h
K
,
K
)
]
,
where, offdiag(X)=X−diag(X).
The method for channel estimation in this embodiment includes: calculating the crosstalk feature of a loaded line according to the measured SNR of the loaded line and the combination of signals sent on other loaded lines. Thus, in this embodiment, no devices need to be redesigned; the measurement time is short; the precision is high; and the robustness is good.
FIG. 3 shows a system for channel estimation in a second embodiment of the present invention. The system includes at least a coordinated transceiver device 1 and an opposite device 2 .
The coordinated transceiver device 1 includes a loading unit 11 , a receiving unit 12 , and a calculating unit 13 . The loading unit 11 is configured to load a combination of signals sent on other lines over a line of a channel. The receiving unit 12 is configured to receive an SNR measured on the loaded line by an opposite device. The calculating unit 13 is configured to calculate crosstalk channels of the loaded line according to a combination coefficient of signals sent on other lines and the received SNR.
The opposite device 2 includes a measuring unit 21 and a sending unit 22 . The measuring unit 21 is configured to measure the SNR of the loaded line. The sending unit 22 is configured to send the measured SNR to the coordinated transceiver device.
FIG. 4 shows a structure of the loading unit of the coordinated transceiver device in this embodiment. The loading unit 11 of the coordinated transceiver device further includes a first calculating unit 111 and a first loading unit 112 . The first calculating 111 is configured to calculate the product of the combination of signals sent on other lines and the step. The first loading unit 112 is configured to load the product of the combination of signals sent on other lines and the step over the loaded line.
The first calculating unit 111 may further include a second calculating unit 1111 . The second calculating unit 1111 is configured to calculate the step according to the transmit power of each line and the SNR before the line is loaded.
The calculating unit 13 of the coordinated transceiver device in this embodiment is also configured to calculate crosstalk channels of the loaded line according to the step and the transmit power of each line.
The system and device for channel estimation in this embodiment calculate the crosstalk feature of a loaded line according to the measured SNR of the loaded line and the combination of signals sent on other loaded lines. Thus, in this embodiment, no devices need to be redesigned; the measurement time is short; the precision is high; and the robustness is good.
FIG. 5 shows a system for channel estimation in a third embodiment of the present invention. The system includes at least a coordinated transceiver device 3 and an opposite device 4 .
The coordinated transceiver device 3 includes a loading unit 31 , a sending unit 32 , and a receiving unit 33 . The loading unit 31 is configured to load a combination of signals sent on other lines over a line of a channel. The sending unit 32 is configured to send a combination coefficient of signals sent on other lines to an opposite device. The receiving unit 33 is configured to receive crosstalk channels calculated for the loaded line by the opposite device.
The opposite device 4 includes a measuring unit 41 , a receiving unit 42 , a calculating unit 43 , and a sending unit 44 . The measuring unit 41 is configured to measure the SNR of the loaded line. The receiving unit 42 is configured to receive the combination coefficient of signals sent on other lines from the coordinated transceiver device. The calculating unit 43 is configured to calculate crosstalk channels of the loaded line according to the combination coefficient of signals sent on other lines and the measured SNR. The sending unit 44 is configured to send the calculated crosstalk channels to the coordinated transceiver device.
FIG. 6 shows a structure of the loading unit of the coordinated transceiver device in this embodiment. The loading unit 31 of the coordinated transceiver device may further include a first calculating unit 311 and a first loading unit 312 . The first calculating 311 is configured to calculate the product of the combination of signals sent on other lines and the step. The first loading unit 312 is configured to load the product of the combination of signals sent on other lines and the step over the loaded line.
The first calculating unit 311 may further include a second calculating unit 3111 . The second calculating unit 3111 is configured to calculate the step according to the transmit power of each line and the SNR of the line before being loaded.
The sending unit 32 of the coordinated transceiver device 3 in this embodiment is also configured to send the step and the transmit power of each line to the opposite device.
Accordingly, in this embodiment, the receiving unit 42 of the opposite device 4 is also configured to receive the step and the transmit power of each line from the coordinated transceiver device; and the calculating unit 43 is also configured to calculate the crosstalk channels of the loaded line according to the received step and transmit power.
The system and device for channel estimation in this embodiment calculate the crosstalk feature of a loaded line according to the measured SNR of the loaded line and the combination of signals sent on other loaded lines. Thus, in this embodiment, no devices need to be redesigned; the measurement time is short; the precision is high; and the robustness is good.
Those skilled in the art may understand that all or part of the steps in the preceding embodiments may be implemented by hardware following instructions of a program. The program may be stored in a computer readable storage medium such as a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or a compact disk.
The preceding embodiments are exemplary embodiments of the present invention only and not intended to limit the protection scope of the invention. It is apparent that various modifications and variations may be made to these embodiments without departing from the scope of the invention. The invention is intended to cover such modifications and variations provided that they fall in the scope of protection defined by the following claims. | A method and apparatus for crosstalk channel estimation based on a measured signal-to-noise (SNR) of a loaded line. The method for channel estimation includes: loading, on a newly added line K, a combination of K−1 signals sent on lines 1 to K−1; obtaining a measured SNR of the line K loaded with the combination of the K−1 signals sent on the lines 1 to K−1; and calculating crosstalk channels of the line K according to K−1 coefficients of the K−1 signals sent on the lines 1 to K−1 and the measured SNR. Embodiments of the present invention may be used for relevant network communications systems such as xDSL systems. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a contact-type image sensor assembly, and, more particularly to a contact-type image sensor assembly for projecting an image of an original document on an image sensor via an imaging lens.
2. Related Background Art
Image sensors for equipment such as facsimile machines and image scanners for use to input images are classified into contraction-type image sensors which contract the image of an original document to be read so as to project it on the sensor and equal-magnification-type image sensors which have an optical system of a 1:1 image focusing type and receiver an image having the same dimension as that of the original document, that is, the same width. An equal-magnification-type image sensor further may have a structure which includes an image focusing lens or may be of a closed contact type which does not include it. Examples of an image sensor which includes an equal magnification imaging lens have been disclosed in Japanese Patent Laid-Open No. 60-230616, Japanese Patent Laid-Open No. 61-25360, Japanese Patent Laid-Open No. 61-25362, U.S. Pat. No. 4,737,654, U.S. Pat. No. 4,724,323, U.S. Pat. No. 4,763,189, U.S. Pat. No. 4,680,644, U.S. Pat. No. 4,920,431, U.S. Pat. No. 4,733,098 and U.S. Pat. No. 4,791,493.
Examples of a closed contact-type image sensor have been disclosed in U.S. Pat. No. 4,924,282, U.S. Pat. No. 4,886,977 and U.S. Pat. No. 4,982,079.
FIG. 1 illustrates an example which uses an equal magnification imaging lens represented by a Selfoc Lens Array (trade name which will be hereinafter called an "SLA") manufactured by Nippon Sheet Glass Co., Ltd. Referring to FIG. 1, reference numeral 1 represents a semiconductor line sensor, 2 represents the aforesaid SLA, 3 represents an LED array for illuminating an original document 5, 4 represents a protection glass on which the original document is placed while being brought into contact with the same, 6 represents a case in which the aforesaid elements are integrally accommodated as a unit and 8 represents a cover for the case 6. Usually, the focal points of the optical system and the other electric characteristics are adjusted in a state where the line sensor 1, the SLA 2, and the LED array 3, and the like, are assembled in the case 6 before delivery to a market as a unit.
Next, the focal point adjustment operation will now be described.
The focal point adjustment operation and the like are performed by vertically moving the SLA 2 by a small quantity. Reference numeral 9 represents a setting screw for securing the SLA 2 to a support wall 6D of the case 6 while pressing the SLA 2 to the support wall 6D after the focal point has been adjusted. The focal point is, as shown in FIG. 2, adjusted by setting a chart (which usually is a white and black stripe chart) 10 for adjusting a lens on the protection glass 4 at a position on which the original document will be placed. Then, the front portion of a focal point adjusting screw 12 is brought into contact with the SLA 2 which is elastically supported by a leaf spring 11 toward a supporting wall 6D, and the SLA 2 is vertically moved by a small quantity while operating the screw 12. Thus, an output obtained from a line sensor (omitted from illustration) is observed by an oscilloscope or the like and the SLA 2 is secured by the setting screw 9 at the moment at which the optimum focal point adjustment is secured. In order to further reliably secure it, an adhesive agent may be used.
Then, the reason why the focal point adjustment must be performed will now be described with reference to FIGS. 3A to 3D.
In general, the optical system, which uses the SLA, must be arranged in such a manner that the distance A from an original document surface 5A to the SLA 2 and the distance B from the SLA 2 to a light receiving surface 1A of the line sensor are the same (that is B=A) (where the distance means an optical distance obtained by dividing the mechanical dimension by the refraction factor of the space medium).
In the process of manufacturing the SLA, the conjugate length Tc which is one of the imaging characteristics is maintained at a guaranteed predetermined value by adjusting the length Z in the direction of an optical axis 31 of the SLA 2 (where the length Z is a mechanical dimension). Therefore, the guaranteed value of the dimension Z of the SLA 2 supplied from an SLA manufacturer is allowed to have a tolerance ΔZ of, for example, about ±0.33 mm. However, if the position of the SLA 2 is, as show in FIG. 3B, deviated from the center of the distance between the original document surface 5A and the light receiving surface 1A of the line sensor 1 while maintaining the relative position between them, the focal point is excessively deviated and the SLA cannot be used practically. Accordingly, it has been necessary to perform a focal-point adjustment operation to, as shown in FIG. 3C, always position the SLA 2 at the optical center between the original document surface 5A and the sensor light receiving surface 1A by realizing a state A'=B' by finely moving the SLA 2 in a direction of the optical axis 31 to change the distance A to A' and change the distance B to B'.
In the contact-type line sensor unit assembly thus adjusted, the original document 5 placed on the protection glass 4 is, as shown in FIG. 1, irradiated with light emitted from the LED array 3 and thereby its image is projected on the line sensor 1 via the SLA 2, so that the original document 5 can be accurately read.
However, it takes an excessively long time to complete the focal-point adjustment operation in the process of assembling the conventional contact-type line sensor assembly, causing the overall cost to be increased excessively.
Furthermore, a gap 12 is formed around the SLA 2 because the SLA 2 must be moved along its supporting wall 6D in the direction of the optical axis for the purpose of adjusting the focal point, causing stray light, which has not passed through the SLA 2, to reach the portion around the line sensor 1 through the gap 12. Therefore, there sometimes arises a problem in that the quality of the image read by the line sensor 1 deteriorates.
In addition, if the SLA 2 is tightened strongly by the setting screw 9 in order to secure the SLA 2 to a predetermined position while withstanding shocks given at the time of transportation or during the operation, another problem takes place in that the SLA 2 will be broken by a concentrated load given through the front portion of the setting screw 9 as shown in FIG. 4.
SUMMARY OF THE INVENTION
Accordingly, an object of the present invention is to overcome the aforesaid problems experienced with the conventional structures by providing an assembly capable of always maintaining the relative positional relationship between a member to be read and the light receiving surface of a line sensor at a state in which focusing is achieved and as well as eliminating a fear of deterioration in the quality of the image due to stray light.
Another object of the present invention is to provide a contact-type image sensor assembly comprising:
an image sensor;
a light source for illuminating an original document which has image information;
an optical lens for imaging light reflected by the original document onto the image sensor; and
a supporting means for supporting the image sensor, the light source and the optical lens, wherein
the supporting member includes:
a first supporting member for maintaining the distance from the surface of the original document and the light incidental side of the optical lens at a predetermined distance;
a second supporting member disposed individually from the first supporting member and acting to maintain the distance from the light emission side of the optical lens to the light receiving side of the image sensor; and
a third supporting member for supporting the first and second supporting members at predetermined positions and
the third supporting member supports the first and second supporting members in this way that their positions can be altered.
Another object of the present invention is to provide a contact-type image sensor assembly comprising:
an image sensor;
a light source for illuminating an original document which has image information;
an optical lens for imaging light reflected by the original document onto the image sensor; and
a supporting member, wherein
the supporting member includes:
a first supporting portion for locating the light incidental side of the optical lens;
a second supporting portion for locating the light emission side of the optical lens; and
a third supporting portion for supporting the first and second supporting portions in this way that the relative position between the first and second supporting portions can be altered.
These and other further objects, features and advantages of the invention will be appear more fully from the following description.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic cross sectional view which illustrates a conventional contact-type image sensor;
FIG. 2 is a schematic perspective view which illustrates the conventional contact-type image sensor;
FIGS. 3a, 3b, 3c, and 3d are schematic views which illustrate a method of adjusting a lens of a contact-type image sensor;
FIG. 4 is a partial enlarged view which illustrates the conventional contact-type image sensor shown in FIG. 1;
FIG. 5 is a schematic cross sectional view which illustrates an embodiment of a contact-type image sensor according to the present invention;
FIG. 6 is a schematic cross sectional view which illustrates another embodiment of the contact-type image sensor according to the present invention;
FIG. 7 is a circuit diagram which illustrates one pixel of the image sensor according to the present invention; and
FIG. 8 is a schematic cross sectional view which illustrates an information processing apparatus on which the contact-type image sensor according to the present invention is mounted.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Preferred embodiments of the present invention will now be described with reference to the drawings. Although the invention has been described in its preferred embodiments, it is understood that the present disclosure of the preferred embodiments may have other details of construction and various combinations and arrangement of parts may be resorted to without departing from the spirit and the scope of the invention as hereinafter claimed.
An embodiment of a contact-type image sensor assembly will now be described which is capable of reading a received image of a subject of the reading operation positioned in contact with the surface of an original-document retainer via an equal magnification imaging lens, the contact-type image sensor being characterized in that: a first supporting member for maintaining the distance from the top surface of the original-document retainer to the surface of the incidental side of the equal magnification imaging lens at a predetermined distance, and a second supporting member positioned in contact with the surface of the emission side of the equal magnification imaging lens and capable of maintaining the distance from the surface of the emission side to the light receiving surface of the line sensor at the aforesaid distance can be integrally coupled to each other while positioning the light receiving surface of the line sensor on the optical axis of the equal magnification imaging lens.
According to this embodiment, if the length of the SLA is changed due to a dimensional error, an image forming relationship can be realized so, and that both the distance from the surface of the original document to the SLA and the distance from the SLA to the light receiving surface of the line sensor are not changed and are always made to be optically the same. Therefore, the necessity of performing the focal point adjustment can be eliminated. Although the distance from the surface of the original document to the light receiving surface (the surface of the line sensor) is changed according to the dimensional error of the SLA, it does not considerably affect the imaging performance. Furthermore, since the dimensional errors of the thickness of the protection glass and the retaining member and the like are sufficiently small (for example, ±0.1 mm or less) as compared with the tolerance of the SLA, it does not affect the imaging performance.
FIG. 5 illustrates an embodiment of the present invention. Referring to FIG. 5, reference numeral 6B represents a retaining member (hereinafter called an "SLA retaining member") for retaining an SLA 2 in the direction of the optical axis and as well as maintaining the distance 1 1 from the top surface of the protection glass 4 and the top surface of the SLA 2 at a predetermined distance. Reference numeral 6C represents a member (hereinafter called a "sensor supporting member") for maintaining the distance 1 2 from the top surface of a line sensor 1 and the lower surface of the SLA 2 at a predetermined distance. Reference numeral 6A represents a case for accommodating the aforesaid elements. Reference numeral 7 represents an elastic member disposed between a supporting frame 21 of the line sensor 1 and a case bottom portion 6E, the elastic member 7 acting to enable the line sensor 1, the sensor supporting member 6C and the SLA 2 to be supported on the surface of the SLA supporting member 6B under the pressure of the supporting frame 21.
The thus arranged contact-type line sensor is assembled in this way that the elastic member 7 is temporarily fastened in the bottom portion 6E of the case 6A. Then, the supporting frame 21 having the line sensor 1, the sensor retaining member 6C, the SLA 2 and the SLA supporting member 6B are, in this sequential order, inserted and placed on the elastic member 7. The case 6A and the SLA supporting member 6B respective have a fastening groove 6F and a fastening claw G which can be fastened to each other so as to strongly press the member 6B to the case 6A, causing the aforesaid two elements to be coupled and integrated with each other by the elasticity of the case 6A. After the aforesaid assembling process has been completed, an LED array 3 and a protection glass 4 are fastened to the member 6B by adhesion or the like and thus the assembling operation is completed.
By employing the contact-type line sensor assembly thus arranged, the required assembling process can be significantly simplified and the complicated focal-point adjustment work taking an excessively long time can be eliminated. Therefore, the assembling cost can be significantly reduced.
Furthermore, a large gap 12 formed between the SLA 2 and the supporting member 6B and that between the SLA 2 and the member 6C and required in the conventional structure can be omitted, causing an effect to be obtained in that the deterioration in the image due to stray light can be prevented.
In addition, since the setting screw 9 for securing the SLA 2 is not used, the breakage of the SLA 2 by the screw 9 can be prevented.
The contraction/extension of the SLA 2 can be compensated by a margin MG between the two retaining member 6B and 6C and the elastic member 7, causing an effect to be obtained that the intervals 1 1 and 1 2 to be always be maintained at a constant value.
That is, the reference surface of a projection 6BB of the supporting member 6B is positioned in contact with the light incidental surface of the SLA 2, causing the movement of the SLA 2 toward a glass 4 to be restricted.
Furthermore, a reference surface 6CC of the supporting member 6C and the light emitting surface of the SLA 2 are positioned in contact with each other, causing the movement of the SLA 2 toward the sensor 1 to be restricted.
As described above, the compensating operation is performed in the case where the SLA 2 is extended. In another case where the SLA 2 is contracted, the retaining members 6B and 6C are brought closer to each other by the pressure of the elastic member 7. The margin MG compensates the contraction of the SLA.
FIG. 6 illustrates another embodiment of the present invention. In this embodiment, the case 6A is omitted, through holes 23 are formed in the sensor supporting frame 21 and the sensor supporting member 6C, thread holes 24 are formed in the SLA supporting member 6B at positions corresponding to the positions of the through holes 23 and fixing screws 25 are inserted to secure the aforesaid elements. According to this embodiment, the number of the required elements can be decreased as compared with the first embodiment.
Also in this embodiment, 11 and 12 can be maintained at a constant distance. That is, the contraction/extension of the SLA 2 can be compensated by adjusting the screw 25.
As described above, according to this embodiment, the first supporting member for maintaining the distance from the top surface of the original-document retainer to the surface of the incidental side of the equal magnification imaging lens at a distance, and a second supporting member positioned in contact with the surface of the emission side of the equal magnification imaging lens and capable of maintaining the distance from the surface of the emission side to the light receiving surface of the line sensor at the aforesaid distance can be integrally coupled to each other while positioning the light receiving surface of the line sensor on the optical axis of the equal magnification imaging lens. Therefore, even if the dimension of the equal magnification imaging lens in the direction of its optical direction is changed in each manufacturing lot, the focal point adjustment operation for making the distance from the surface of the original document to the surface of the incident side of the equal-magnification imaging lens and the distance from the surface of the emission side of the equal-magnification imaging lens and the top surface of the line sensor to be the same can be eliminated. Furthermore, the assembling process can be simplified significantly and the deterioration in the quality of the image due to stray light and the breakage of the equal magnification imaging lens due to the setting screw can be prevented.
As the light sensor 1, it is preferable that a long photosensor of a type disclosed in U.S. Pat. No. 4,461,956 granted to Hatanaka and others, inventors, and comprising a photoelectric conversion layer made of amorphous silicon be employed because of its low price and excellent resolution.
It is preferable to use a photosensor of a type disclosed in U.S. Pat. No. 4,791,469 granted to Ohmi and others, inventors, and U.S. Pat. No. 4,810,896 granted to Tanaka and others, inventors, and arranged to provide a capacitive load connected with the emitter of a bipolar transistor to read an output signal from the emitter with voltage across the capacitive load.
FIG. 7 illustrates an equivalent circuit which corresponds to one pixel of the sensor 1 according to the present invention.
Referring to FIG. 7, symbol PS represents a bipolar transistor which forms a pixel, SW 1 represents an nMOS transistor serving as a switch means for performing a resetting operation by connecting the emitter to a reference voltage source V ES . Symbol SW 2 represents a pMOS transistor serving as a switch means for performing a resetting operation by connecting the base to a reference voltage source V BB . Symbol SW 3 represents an nMOS transistor serving as a switch means for transferring the change of the signal and C T represents a capacitive load in which the voltage of the signal is generated.
Resetting Operation:
First, negative pulse voltage is applied to the gate of the pMOS transistor SW 2 , so that the base is clamped to the voltage V BB .
Although the aforesaid first and second embodiments are described about the charge storage and amplifying type image sensor which uses the bipolar transistor, the present invention may preferably be embodied in sensors of a type which has a light receiving portion made of light diode and in which the charge of the signal is transferred by an MOS switch or a charge coupled device (CCD) or the like.
FIG. 8 illustrates an example of a facsimile machine serving as the image processing processing apparatus formed by using the contact-type image sensor assembly and having a communicating function. Referring to FIG. 8, reference numeral 102 represents a feeding roller serving as a feeding means for feeding original document PP to a reading position. Reference numeral 104 represents a separating member for reliably separating an individual original document PP to feed it. Reference numeral 106 represents a platen roller disposed to correspond to the position at which the sensor assembly reads the original document PP to restrict the surface of the original document PP to be read and serving as a conveying means for conveying the original document PP.
Symbol P represents a recording medium formed into a roll paper on which image information read by the sensor assembly or, in a case of the facsimile apparatus or the like, image information transmitted from outside, is reproduced. Reference numeral 110 represents a recording head serving as a recording means for use to form the aforesaid image and may be a thermal head, or an ink jet recording head, or the like. The aforesaid recording head may be either a serial type recording head or a line type recording head. Reference numeral 112 represents a platen roller serving as a conveying means for conveying the recording medium P to a position at which the recording head 110 records image information and restricting the surface of the recording medium P to be recorded.
Reference numeral 120 represents an operation panel having switches serving as input/output means for receiving input operations, and display portion for displaying messages and the status of the apparatus, and the like.
Reference numeral 130 represents a system control substrate serving as a control means having a control portion (controller) for controlling each unit, a drive circuit (a driver) for driving a photoelectrically converting device, an image information processing portion (a processor) and an information transmitting/receiving portion and the like. Reference numeral 140 represents a power source of the apparatus.
It is preferable that the recording means for use in the information processing apparatus according to the present invention be a recording means of a type the
Then, Positive pulse voltage is applied to the gate of the nMOS transistor SW 1 , so that the emitter is connected to the voltage source V ES and thereby an electric current flows between the base and the emitter. As a result, a light generating carrier stored in the base is extinguished.
Storage Operation:
Both of the nMOS transistors SW 1 and SW 3 are turned off, causing both of the emitter and the base to be brought into the floating state. As a result, the storage operation is commenced.
Reading Operation:
Then, positive pulse voltage is applied to the gate of the nMOS transistor SW 3 , so that SW 3 is switched on, causing the emitter and the capacitance CT to be connected to each other. As a result, the portion between the base and the emitter are biased forward and the voltage of the signal is read out in the capacitance CT.
The basic structure of an image sensor of the aforesaid type has been disclosed in U.S. Pat. No. 4,686,554 granted to Ohmi and Tanaka, inventors, and arranged as an excellent sensitive and low noise photoelectrically converting apparatus of a charge storage type in which the emitter of a bipolar transistor is connected to an output circuit including a capacity load. typical structure and the principle of which have been disclosed in U.S. Pat. No. 4,323,129 and U.S. Pat. No. 4,740,796. The aforesaid structure is arranged in this way that electrothermal converting members disposed to correspond to a sheet or a liquid passage which holds liquid (ink) are applied with one or more drive signal which rapidly raise the temperature of the electrothermal converting members to a level higher than the nuclear boiling level. As a result, heat energy is generated in the electrothermal converting member to cause the film boiling to take place in the surface of the recording head which receives heat. Therefore, an effect can be obtained in that bubble can be formed in liquid (ink) corresponding to each drive signal. When the bubble is enlarged and contracted, liquid (ink) is discharged through a discharge port, so that one or more droplets are formed.
As the full line type recording head having a length which is the same as the width of the maximum recording medium adapted to the recording apparatus, a structure may be employed which has the length realized by combining a plurality of the recording heads disclosed in the aforesaid specifications or an integrated type single recording head may be employed.
The present invention may be effectively embodied in a structure which uses an interchangeable chip type recording head which is mounted on the apparatus body and which enables, in this state, an electrical connection with the apparatus body to be established and ink to be supplied or a structure which uses a cartridge type recording head formed by integrally forming an ink tank with the recording head. | A contact-type image sensor assembly including: an image sensor; a light source for illuminating an original document which has image information; an optical lens for imaging light reflected by the original document onto the image sensor; and a supporting member for supporting the image sensor, the light source and the optical lens, wherein the supporting member includes: a first supporting member for maintaining the distance from the surface of the original document and the light incidental side of the optical lens at a predetermined distance; a second supporting member disposed individually from the first supporting member and acting to maintain the distance from the light emission side of the optical lens to the light receiving side of the image sensor; and a third supporting member for supporting the first and second supporting members at predetermined positions and the third supporting member supports the first and second supporting members in this way that their positions can be adjusted. | 7 |
TECHNICAL FIELD
The present invention relates to a lamination station for laminating film to a web of paperboard or cardboard material.
BACKGROUND ART
In the lamination of packaging materials, for example for liquid packages, it is normal practice to start from a web of paperboard or cardboard, one or both sides of the web being coated with different types of films or material layers in order for the finished packaging material to attain the desired properties. Those layers which are employed for coating the paperboard or cardboard material are principally different types of plastic films, but different types of metal foils (e.g. Alifoil) may be employed. The plastic layers and the possible metal foil fulfil the purpose of preventing action between the product which is to be packed and the packaging material. Another purpose is to prevent e.g. oxygen from penetrating into the package.
Most generally, the web of paperboard or cardboard is delivered in the form of a magazine reel. The magazine reel is applied in one end of a lamination machine, which comprises a number of rollers which together form a path for the web. In order to realise the compressive force necessary for the lamination, generally two rollers are applied close to one another, so that a nip is formed between the rollers. In order to obtain a satisfactory adhesion between, for example, a plastic film and the paperboard/cardboard, the pressure in the nip should be maintained for a certain time at a given pressure. In general, it may be said that if the pressure is low, the time should be long, and vice versa.
One problem occurs if the web of paperboard or cardboard is of low density, i.e. is “fluffy”; if the intention is to maintain the low density also after the nip between the rollers, the pressure should be low (i.e. the clearance between the rollers should be large), otherwise the web will be compressed by the pressure in the nip. As was mentioned previously, the adhesion between the web and the film which is to be laminated depends upon the time during which the web is exposed to pressure as well as the pressure at which the web is exposed. If the pressure is low, the time spent in the nip should thus be long in order to reach the same level of adhesion.
There are two ways of extending the time during which a nip between two rollers subjects a web to pressure: the first method is to reduce the web speed, but from the viewpoint of production economics this is less suitable. The other possibility is to increase the diameter of the rollers, but the point is soon reached where the size of the rollers becomes unreasonable.
Moreover, the prior art lamination machines are designed for a given lamination pressure. This implies that the rollers may have a slightly convex form, which compensates for the outward flexing of the rollers, and at a certain compressive force between the rollers gives a uniform pressure throughout the entire width of the rollers. If the force between the rollers is increased or reduced, the convexity of the rollers will not correspond to the outward flexing of the rollers, for which reason the range within which it is possible to modify the compressive force between the rollers is limited.
EP 1 345 756 describes a roller comprising an inner, rigid core surrounded by two layers of resilient material. If one such roller is employed there will, granted, be a slightly longer nip, but the major reason for using such a roller is that there will be obtained a nip which is relatively insensitive to variations in the thickness of the web.
BRIEF SUMMARY OF THE INVENTION
The problem in obtaining a long press time in the nip is solved according to the present invention in that the nip roller consists of a shoe-press type pressure roller.
In order to realise adhesion between a material layer or a film and a web of paperboard or cardboard, an interjacent molten polymer layer or adhesive layer may be provided between the film and the web of paperboard.
In order to obtain superior properties relating to liquid and air tightness, the film may consist of a polymer film or an aluminium foil (Alifoil). The material layer may also be a molten polymer which is applied on the web of paperboard by means of extrusion coating.
In order to obtain the requisite length of the nip, the pressure roller includes a press web, the press web running parallel with and at the same speed as the web of paperboard, the press web being urged against the cooling roller by means of one or more pressure bars, extending along the roller, provided for this purpose.
In order to be able to regulate the compressive force during operation, the pressure bar may be an elongated member having a profile resembling a kind of “shoe”, which is pressed against the press webb, normally by hydraulic pressure mechanisms acting upon the shoe-shaped member. This technology is known in the field of paper calendaring as the conventional type of shoe-press technology. Alternatively and according to more modern shoe-press technology, the pressure bar may include a battery of hydraulically activated elements for creating the pressure against the press web and the pressure profile within the nip.
One preferred application of a lamination station including a shoe press roller nip may be the manufacture of packaging materials.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
The present invention will now be described in greater detail hereinbelow, with reference to the accompanying Drawings. In the accompanying Drawings:
FIG. 1 is a schematic side elevation of a lamination station according to the present invention; and
FIG. 2 is a schematic side elevation which shows a nip between a shoe-press type roller and a cooling roller according to one embodiment of the invention.
FIG. 3 is a schematic side elevation which shows a nip between a shoe-press type roller and a cooling roller according to an alternative embodiment of the invention.
DESCRIPTION OF PREFERRED EMBODIMENTS
FIGS. 1 , 2 and 3 show a part of a lamination machine intended for coating a web of paperboard 110 with a film 120 . In order to fix the film 120 to the paperboard 110 , there is provided a thin layer 130 in the form of a molten polymer or an adhesive between the paperboard 110 and the film 120 . In order to generate the pressure and temperature reduction requisite for lamination, the paperboard 110 , the film 120 and the polymer melt 130 are pressed together between a press or nip roller 150 and a cooling roller 160 . That region which is put under pressure between these rollers is generally entitled the nip, and its extent in the longitudinal direction of the web 110 is determined on the one hand by the force between the cooling roller and the nip roller, and on the other hand by how resilient the material in the nip roller and the cooling roller is. Not seldom, the cooling roller 160 is cooled, e.g. by means of an inner water cooling device (not shown).
In another embodiment of the present invention, it is possible to dispense with the thin layer 130 and instead employ a film 120 which is coated with an adhesive or hot melt layer (not shown), this layer facing towards the web of paperboard 110 . It is then also possible to obtain in the nip such a pressure and temperature that the film 120 adheres to the paperboard 110 by wholly or partly melting (so-called “hot cylinder lamination”).
In lamination machines according to prior art technology, both the cooling roller 160 and the nip roller 150 are largely cylindrical. This entails that the nip will be relatively short, unless a large force urges the rollers together. However, there are a plurality of drawbacks in employing a large force, e.g. that the paperboard 110 will be subjected to a compression which reduces its rigidity or stiffness. The short nip according to the prior art technology entails that the stay-time in the nip will be short, which limits the speed at which the web can pass through the nip. Moreover, the high pressure in the nip makes it difficult to employ economical paperboard types as the paperboard 110 , since low price paperboard types generally possess low density, with the result that their tendency to be compressed together by the nip is manifest. If a paperboard is compressed together, its thickness will be reduced and a reduced thickness implies that the rigidity of the material is reduced, which in turn implies that a package manufactured from the material runs the risk of losing its shape.
According to the present invention, the nip roller 150 is a so-called shoe roller; the function of such a shoe roller will be explained hereinbelow with reference to FIG. 2 and FIG. 3 .
A nip roller 150 according to one embodiment of the present invention includes a press web 155 , which in operation runs at the same speed as the cooling roller 160 , the web of paperboard 110 and the film 120 . The pressure requisite for the lamination is generated in that the press web 155 is urged by at least one pressure bar 157 against the cooling roller 160 . The bar 157 is positioned stationarily in relation to the cooling roller 160 , which implies that the press web 155 will slide against a front surface 158 of the bar 157 .
By using a nip roller 150 of the shoe roller type, it will be possible to distribute the nip over a greater area, which in turn makes it possible either to increase the lamination speed while maintaining a long press time, or to have a lower pressure and longer press time.
There is a plurality of different types of shoe rollers; a feature common to them however is that they are provided with a press web 155 which has the same speed as a counter roller (according to the present invention a cooling roller) and which slides against a pressure-generating bar provided to create a pressure between the press web 155 and the counter roller. Shoe rollers for the paper industry are commercially available (for example Metso paper Karlstad sells shoe rollers under the trademarks Optidwell and Symbelt). Shoe rollers intended for the paper industry differ however from rollers suitable for lamination in that the shoe rollers suitable for the paper industry give a considerably higher compression pressure; it is not uncommon that the compression pressure within the paper industry is 3 to 4 times higher than that required for lamination.
The pressure bar 157 according to FIG. 2 is provided with a battery, or number, e.g. three, of individually governable pressure elements 157 ′ 157 ″ and 157 ′″. In certain embodiments of the present invention, the pressure elements 157 ′, 157 ″ and 157 ′″ extend throughout the entire length of the shoe roller, with the result that the compression pressure will be uniformly distributed throughout the entire length. In other embodiments, it may be desirable that some of the pressure elements do not extend throughout the entire length, with the result that the nip may be varied over the width of the web.
In this embodiment of the present invention, the pressure elements 157 ′, 157 ″ and 157 ′″ consist of an elongate flexible die having multiple chambers containing a hydraulic liquid, each chamber representing a pressure element. There may be several pressure elements, from 2 up to what is practically feasible, but normally from 2 to 6. The die is pressed against the press web by means of a hydraulic pressure provided beneath the die from the chambers, the force being transferred from the die to the press web 155 and via the web 110 to the cooling roller 160 .
The hydraulic pressure also affords the major advantage that the compression pressure will be uniform along the entire width of the web, since the hydraulic pressure equalizes out any possible outward flexing of the nip- and cooling rollers.
According to an alternative embodiment of the present invention, as shown in FIG. 3 , multiple press devices 157 , 157 ′ (there may be several further press devices, however not shown) are disposed as elongate bars, strips or beads of a rigid material. The bars, strips or beads extend over substantially the entire width of the press web 155 and may be urged against it by means of hydraulic cylinders.
Yet a further advantage inherent in the present invention is that the press web 155 may be coated with a material displaying a certain resilient yieldability, e.g. in order to realise a nip similar to that described in EP 1 345 756. This provides the property that the compression pressure will be more “elastic”, which implies that the compression pressure reaches into regions where the paperboard is perforated, in order e.g. to realise an indication for the penetration of a drinking straw.
In both of the above-described embodiments, it is possible to regulate the pressure in the nip during operation, by increasing or reducing the hydraulic pressure.
Yet a further advantage inherent in the present invention is that the long nip between the nip roller and the cooling roller may improve lamination of e.g. porous paperboard or porous plastic layers without at the same time damaging these layers. | A lamination station for laminating a film to a web of paperboard includes a nip roller and a cooling roller. Between the rollers there is formed a nip which presses together the film and the web of paperboard with an interjacent molten polymer layer or adhesive layer disposed between the film and the web of paperboard. The film, the paperboard and the molten polymer lie, after the nip, in abutment against the cooling roller for a certain angle interval. The nip roller is a shoe-press type roller, either comprising a pressure bar having several hydraulically operated pressure elements, or comprising one or several rigid pressure bars. | 8 |
This application is a divisional of U.S. application Ser. No. 11/209,752, filed Aug. 24, 2005 now U.S. Pat. No. 7,745,900, the entire disclosure of which is hereby incorporated by reference.
FIELD OF THE INVENTION
The invention relates to solid state imagers, display devices, and more particularly to optical paths used in solid state imagers and display devices.
BACKGROUND OF THE INVENTION
Solid state imagers generate electrical signals in response to light reflected by an object being imaged. Complementary metal oxide semiconductor (CMOS) imagers are one of several different known types of semiconductor-based imagers, which include for example, charge coupled devices (CCDs), photodiode arrays, charge injection devices and hybrid focal plane arrays.
Some inherent limitations in CCD technology have promoted an increasing interest in CMOS imagers for possible use as low cost imaging devices. A fully compatible CMOS imager technology enabling a higher level of integration of an image array with associated processing circuits would be beneficial to many digital image capture applications. CMOS imagers have a number of desirable features, including for example low voltage operation and low power consumption. CMOS imagers are also compatible with integrated on-chip electronics (control logic and timing, image processing, and signal conditioning such as A/D conversion). CMOS imagers allow random access to the image data, and have lower manufacturing costs, as compared with conventional CCDs, since standard CMOS processing techniques can be used to fabricate CMOS imagers. Additionally, CMOS imagers have low power consumption because only one row of pixels needs to be active at any time during readout and there is no charge transfer (and associated switching) from pixel to pixel during image acquisition. On-chip integration of electronics is particularly desirable because of the potential to perform many signal conditioning functions in the digital domain (versus analog signal processing) as well as to achieve reductions in system size and cost.
Nevertheless, demands for enhanced resolution of CCD, CMOS and other solid state imaging devices, and a higher level of integration of imaging arrays with associated processing circuitry, are accompanied by a need to improve the light sensing characteristics of the pixels of the imaging arrays. For example, it would be beneficial to minimize, if not eliminate, the loss of light transmitted to individual pixels during image acquisition and the amount of crosstalk between pixels caused by light being scattered or shifted from one pixel to a neighboring pixel.
A significant source of photon reflection can occur at the junction of different media, each having a different refractive index. Photon reflection between two different media can be expressed by the following formula:
R = ( n 1 - n 2 ) 2 ( n 1 + n 2 ) 2
where n 1 and n 2 are the refractive indices of the two media and R is the percentage of photons reflected at the junction of the two media.
Silicon and silicon oxide layers are required in many conventional CMOS photosensor structures because of the limitations of conventional CMOS technology and the high quantum efficiency of a crystallized silicon based photodiode.
With reference to FIGS. 1( a )-( c ), which respectively illustrate a top-down view, a partial cross-sectional view and electrical circuit schematic of a conventional CMOS pixel sensor cell 100 , when incident light 187 strikes the surface of a photosensor (photodiode) 120 , electron/hole pairs are generated in the p-n junction of the photosensor (represented at the boundary of n-type accumulation region 122 and p-type surface layer 123 [ FIG. 1( b )]). The generated electrons (photo-charges) are collected in the n-type accumulation region 122 of the photosensor 120 . The photo-charges move from the initial charge accumulation region 122 to a floating diffusion region 110 via a transfer transistor 106 . The charge at the floating diffusion region 110 is typically converted to a pixel output voltage by a source follower transistor 108 and then output on a column output line 111 via a row select transistor 109 .
Conventional CMOS imager designs, such as that shown in FIGS. 1( a )-( c ) for pixel cell 100 , include a substrate 101 having a photosensor 120 and isolation regions 102 . The floating diffusion region 110 is coupled to a transfer transistor gate 106 ′ of the transfer transistor 106 . Source/drain regions 115 are provided for reset 107 , source follower 108 , and row select 109 transistors which have respective gates 107 ′, 108 ′, and 109 ′. A silicon dioxide layer 150 is typically formed over the substrate 101 to form a silicon-silicon dioxide stack, for example, as a protective layer.
A silicon/silicon dioxide stack 20 is shown in FIG. 2( a ). A first layer 22 having a first refractive index, which corresponds to silicon dioxide layer 150 of FIG. 1( b ), is formed on a second layer 21 having a second refractive index, corresponding to silicon substrate 101 of FIG. 1( b ). However, formation of silicon dioxide on top of a silicon photodiode can lead to significant reflection at the junction of the two layers. Where the first layer is silicon dioxide (at or about n=1.45) and the second layer is silicon (at or about n=4), the stack 20 produces reflection R of about 22% of photons at the junction 23 of the first and second layers.
FIG. 2( b ) shows a plot of the refractive index n of the stack of FIG. 2( a ) relative to depth d. At the depth of junction 23 , the refractive index n rises sharply from 1.5 to 4.0. FIG. 2( c ) shows a plot of the total reflection R within the stack of FIG. 2( a ) relative to depth d. At the junction 23 , where n jumps from 1.5 to 4.0, the percentage reflection R spikes to 22%, which is undesirable. Referring back to FIG. 1( b ), a significant quantity of photons is reflected at the junction between substrate 101 and silicon dioxide layer 150 , and thus are not detected by the imager.
Accordingly, there is a need and desire for an improved solid state imaging device, capable of receiving and propagating light with minimal loss of light transmission to a photosensor. There is also a need and desire for improved fabrication methods for imaging devices that provide a high level of light transmission to the photosensor and reduce the light scattering drawbacks of the prior art, such as crosstalk and photon reflection.
There is also a need for improved display devices which utilize an array of photoemitters for light emission which also have improved light propagating properties.
BRIEF SUMMARY OF THE INVENTION
Exemplary embodiments of the invention provide a transient index stack having an intermediate transient index layer, for use in an imaging device or a display device, that reduces reflection between layers having different refractive indexes by making a gradual transition from one refractive index to another. Other embodiments include a pixel array in an imaging or display device, an imager system having improved optical characteristics for reception of light by photosensors and a display system having improved optical characteristics for transmission of light by photoemitters. Enhanced reception of light is achieved by reducing reflection between a photolayer, for example, a photosensor or photoemitter, and surrounding media by introducing an intermediate layer with a transient refractive index between the photolayer and surrounding media such that more photons reach the photolayer. The surrounding media can include a protective layer of optically transparent media.
Methods for forming an imaging device, in accordance with exemplary embodiments of the invention, include forming one or more intermediate transient index layers between media layers, having different indexes of refraction, disposed over focal plane arrays of photosensors. The exemplary methods include the acts of forming photosensors on a wafer, providing an intermediate transient index layer, and providing an optically transparent medium over the intermediate transient index layer, for example, as a protective layer. A color filter layer may also be fabricated with an individual color filter over a respective photosensor/intermediate transient index layer stack and a microlens structure layer can be fabricated over the color filter layer.
Also disclosed are structures and fabrication methods for optical paths used in display devices which have improved optical characteristics for transmission of light from photoemitters.
These and other features and advantages of the invention will be more apparent from the following detailed description that is provided in connection with the accompanying drawings illustrating exemplary embodiments of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1( a ) is a top-down view of a conventional four transistor CMOS pixel cell.
FIG. 1( b ) is a cross-sectional view of the pixel cell of FIG. 1( a ), taken along line 1 - 1 ′.
FIG. 1( c ) is a circuit diagram of the conventional CMOS pixel of FIGS. 1( a ) and ( b ).
FIG. 2( a ) is a cross sectional view of an optical stack having a silicon dioxide layer formed on a silicon layer according to the prior art.
FIG. 2( b ) is a plot of the transient index n of the stack of FIG. 2( a ) relative to depth d.
FIG. 2( c ) is a plot of the total reflection R within the stack of FIG. 2( a ) relative to depth d.
FIG. 3( a ) is a cross sectional view of a stack having a silicon dioxide layer formed on a silicon layer and also having an intermediate transient index stack in accordance with a first exemplary embodiment of the invention.
FIG. 3( b ) is a plot of the transient index n of the stack of FIG. 3( a ) relative to depth.
FIG. 3( c ) is a plot of the percentage reflection R within the stack of FIG. 3( a ) relative to depth d.
FIG. 4( a ) is a cross sectional view of a stack having a silicon dioxide layer formed on a silicon layer and also having an intermediate transient index stack in accordance with a second exemplary embodiment of the invention.
FIG. 4( b ) is a plot of the transient index n of a stack of FIG. 4( a ), relative to depth.
FIG. 4( c ) is a plot of the percentage reflection R within the stack of FIG. 4( a ) relative to depth d.
FIG. 4( d ) is a plot of the total percentage reflection of all light passing through the stack according to the second exemplary embodiment in relation to the number of discrete transient index layers.
FIG. 5( a ) is a cross sectional view of a stack having a silicon dioxide layer formed on a silicon layer and also having an intermediate transient index stack in accordance with a third exemplary embodiment of the invention.
FIG. 5( b ) is a plot of the transient index n of a stack of FIG. 5( a ), relative to depth.
FIG. 5( c ) is a plot of the percentage reflection R within the stack of FIG. 5( a ) relative to depth d.
FIG. 6 is a cross-sectional view of a CMOS pixel cell comprising an intermediate transient layer according to the invention.
FIG. 7 depicts a block diagram of an imager device constructed in accordance with an embodiment of the invention.
FIG. 8 depicts a processor system incorporating at least one imager device constructed in accordance with an embodiment of the invention.
DETAILED DESCRIPTION
In the following detailed description, reference is made to various specific embodiments which exemplify the invention. These embodiments are described with sufficient detail to enable those skilled in the art to practice the invention, and it is to be understood that other embodiments may be employed, and that structural and logical changes may be made without departing from the spirit or scope of the invention.
The term “substrate” used in the following description may include any semiconductor-based structure. The structure should be understood to include silicon, silicon-on insulator (SOI), silicon-on-sapphire (SOS), doped and undoped semiconductors, epitaxial layers of silicon supported by a base semiconductor foundation, and other semiconductor structures. The semiconductor need not be silicon-based. The semiconductor could be silicon-germanium, germanium, or gallium arsenide. When reference is made to the substrate in the following description, previous process steps may have been utilized to form regions or junctions in or over the base semiconductor or foundation.
An intermediate layer having a transient refractive index is particularly advantageous when formed between a silicon photosensor layer and a protective silicon dioxide layer such as those found in, e.g., CMOS imager pixel cells. The intermediate layer may be formed by different methods, for example, by silicon quantum dot formation, by reactive physical vapor deposition (“PVD”), or by chemical vapor deposition (“CVD”).
Silicon quantum dot formation creates silicon “dots” each having a diameter smaller than the wavelength of visible light in an intermediate silicon dioxide layer. By forming dots such that the size and/or distribution density of the dots decreases uniformly from the silicon layer to the silicon dioxide layer, the reflection is minimized at the junctions of the intermediate layer and the respective silicon and silicon dioxide layers, and throughout the intermediate layer.
Reactive PVD and CVD deposition can also generate an intermediate layer having reduced photon reflection by gradually increasing oxygen flow during deposition of silicon. By controlling the oxygen flow as a function of deposition time, the resultant intermediate transient layer has a smooth transition from pure silicon to silicon dioxide.
FIG. 3( a ) is a cross sectional view of an optical stack 30 formed in accordance with a first exemplary embodiment of the invention. The stack 30 comprises a silicon base layer 31 , a silicon dioxide layer 32 and an intermediate transient layer 33 between layers 31 and 32 . The intermediate transient layer 33 has a refractive index at or about n=4.0 at the junction 34 between the silicon base layer 31 and the intermediate transient layer 33 and a refractive index at or about n=1.5 at the junction 35 between the silicon dioxide layer 32 and the intermediate transient layer 33 . The refractive index n of the intermediate transient layer gradually transitions from at or about n=1.5 at junction 34 to at or about n=4.0 at junction 35 , thereby reducing reflection at the junctions 34 , 35 and throughout the intermediate transient layer 33 .
The intermediate transient layer may be formed on a silicon substrate, for example, by adding silicon dioxide in increasing proportion during layer formation until a pure silicon dioxide layer is achieved. More specifically, an intermediate transient index may be formed on a silicon substrate by using reactive sputter PVD deposition of silicon; by gradually increasing flow of oxygen during the reactive sputter deposition, the refractive index n of the intermediate transient index layer would gradually increase from at or about n=1.5 to at or about n=4.0 for example. Similarly, CVD deposition can achieve the same results, by increasing the proportion of precursors as a function of layer depth.
FIG. 3( b ) is a plot of the transient refractive index n of the stack of FIG. 3( a ) relative to depth d. Unlike the plot shown in FIG. 2( b ), FIG. 3( b ) shows a change in refractive index n relative to depth d that is more gradual and less abrupt than at the junction 23 in FIG. 2( b ).
FIG. 3( c ) shows a plot of the total reflection R within the stack of FIG. 3( a ) relative to depth d. Here, the reflection increases with the change in n shown in FIG. 3( b ), but to a lesser extent than in the conventional stack 20 , as shown in FIGS. 2( a ) and 2 ( c ). Fewer photons are reflected at junction, and many photons can be recovered once they enter the intermediate transient layer because the same change in refractive index n will re-reflect a percentage of the reflected photons back in the correct direction. This photon recovery is not possible with the conventional stack 20 of FIG. 2( a ), which has no way to re-reflect photons that have been reflected at junction 23 .
FIG. 4( a ) is a cross sectional view of a stack 40 having a silicon dioxide layer 42 formed over a silicon layer 41 and with an intermediate transient index stack 43 in accordance with a second exemplary embodiment of the invention formed therebetween. In this embodiment, discrete layers 43 ( a )-( f ) having incrementally larger refractive indexes in the direction of the substrate are formed over the silicon substrate 41 . In the illustrated embodiment, beginning with a silicon substrate 41 , each discrete intermediate layer 43 ( a )-( f ) has an incrementally higher proportion of silicon dioxide than the prior layer, ultimately reaching pure silicon dioxide concentration in the final layer 43 ( a ). A uniform silicon dioxide layer 42 may then be formed over the intermediate transient index stack 43 .
FIG. 4( b ) is a plot of the transient refractive index n of the stack of FIG. 4( a ) relative to depth d. Here, the change in refractive index n relative to depth d takes place incrementally and reduces overall reflection. FIG. 4( c ) is a plot of the percentage reflection R within the stack of FIG. 4( a ) relative to depth d. The percentage reflection R is dispersed into a series of smaller spikes at the junction between each layer 43 ( a )-( f ) than the single large spike of FIG. 2( c ). The spikes at each junction may also re-reflect and thereby recover reflected photons.
The embodiment shown in FIG. 4( a ) uses 6 discrete layers 43 ( a )-( f ), but any number of layers may be used with varying results, as discussed below with respect to FIG. 4( d ).
One advantage of the embodiment illustrated in FIG. 4( a ) over the embodiment illustrated in FIG. 3( a ) is reduced cost of fabrication. In situations where a tradeoff between fabrication cost and percentage of photon reflection is permitted, fabrication cost can be dramatically reduced by employing fewer discrete layers during fabrication. FIG. 4( d ) is a plot of the total reflection percentage of an optical stack according to the second exemplary embodiment in relation to the number of discrete transient index layers, illustrating the cost/benefit tradeoff between the number of discrete layers and overall reflection. With a greater number of discrete layers, the change in refractive index n at each junction is less drastic, and produces a smaller series of spikes in reflection percentage R.
FIG. 5( a ) is a cross sectional view of a stack 50 having a silicon dioxide layer 52 formed on a silicon layer 51 and also having an intermediate transient index stack in accordance with a third exemplary embodiment of the invention. FIG. 5( a ) shows an intermediate silicon dioxide transient layer containing silicon quantum dots 53 formed therein. By using quantum dots 53 smaller than the wavelength of visible light (<0.2 um) and by adjusting the distribution density of the dots 53 in the intermediate transient index layer, the layer can be made optically equivalent to the optimum intermediate transient index layer 33 of FIG. 3( a ).
FIG. 5( b ) is a plot of the transient refractive index n of the stack of FIG. 5( a ) relative to depth d. Like FIG. 3( b ), FIG. 5( a ) shows a change in refractive index n relative to depth d that is smoother and less abrupt than at the junction 23 in FIG. 2( b ). FIG. 5( c ) is a plot of percentage reflection relative to depth d which, like FIG. 3( c ), produces less total reflection than the optical stack of FIG. 2( a ).
The methods of forming the intermediate transient index layer are flexible and can be adjusted according to the tolerances and desired optical characteristics of the imaging or display device.
FIG. 6 illustrates the use of an optical stack, e.g., stacks 30 , 40 , 50 , according to the invention in an imager pixel cell 100 ′, with layer 151 corresponding to an intermediate transient layer according to any one of the embodiments described above. The remainder of the cell 100 ′ may be the same as the conventional cell 100 ( FIG. 1( b )).
FIG. 7 illustrates a block diagram of an exemplary CMOS imager 108 having a pixel array 140 comprising a plurality of pixel cells 100 ′ arranged in a predetermined number of columns and rows, with each pixel cell being constructed as illustrated and described above with respect to FIG. 6 . Other known pixel architectures may be used, but all will include intermediate transient layer 151 as described above with respect to FIG. 6 . Attached to the pixel array 140 is signal processing circuitry for controlling the pixel array 140 , as described herein, at least part of which may be formed in the substrate. The pixel cells of each row in array 140 are all turned on at the same time by a row select line, and the pixel cells of each column are selectively output by respective column select lines. A plurality of row select and column select lines are provided for the entire array 140 . The row lines are selectively activated by a row driver 145 in response to row address decoder 155 . The column select lines are selectively activated by a column driver 160 in response to column address decoder 170 . Thus, a row and column address is provided for each pixel cell.
The CMOS imager 108 is operated by a timing and control circuit 152 , which controls address decoders 155 , 170 for selecting the appropriate row and column lines for pixel readout. The control circuit 152 also controls the row and column driver circuitry 145 , 160 such that they apply driving voltages to the drive transistors of the selected row and column lines. The pixel column signals, which typically include a pixel reset signal V rst and a pixel image signal V sig , are output to column driver 160 , on output lines, and are read by a sample and hold circuit 161 . V rst is read from a pixel cell 100 ′ immediately after the floating diffusion region 110 is reset. V sig represents the amount of charges generated by the photosensitive element of the pixel cell 100 ′ in response to applied light during an integration period. A differential signal (V rst −V sig ) is produced by differential amplifier 162 for each readout pixel cell. The differential signal is digitized by an analog-to-digital converter 175 (ADC). The analog to digital converter 175 supplies the digitized pixel signals to an image processor 180 , which forms and outputs a digital image.
FIG. 8 illustrates a processor-based system 1100 includes an imaging device 108 constructed in accordance with an embodiment of the invention, CPU 1102 , RAM 1110 , I/O device 1106 , and removable memory 1115 . As discussed above, the imaging device 108 contains a pixel array 140 having a plurality of pixel cells 100 ′, each having a transient index stack formed and used as described herein. The processor-based system 1100 is exemplary of a system having digital circuits that could include image sensor devices. Without being limiting, such a system could include a computer system, camera system, scanner, machine vision, vehicle navigation, video phone, surveillance system, auto focus system, star tracker system, motion detection system, image stabilization system, and other image sensing and/or processing system.
The processor-based system 1100 , for example a camera system, generally comprises a central processing unit (CPU) 1102 , such as a microprocessor, that communicates with an input/output (I/O) device 1106 over a bus 1104 . Imaging device 308 also communicates with the CPU 1102 over the bus 1104 . The processor-based system 1100 also includes random access memory (RAM) 1110 , and can include removable memory 1115 , such as flash memory, which also communicates with CPU 1102 over the bus 1104 . Imaging device 308 may be combined with a processor, such as a CPU, digital signal processor, or microprocessor, with or without memory storage on a single integrated circuit or on a different chip than the processor. The above techniques, structure and system can be applied to display devices employing photoemitters as well. For example, a pixel array similar to the array 140 of FIG. 7 , but employing photoemitters employing the present invention rather than photosensors, may be used in a display device to reduce internal reflection and to emit a more accurate signal.
The above description and drawings are only to be considered illustrative of exemplary embodiments which achieve the features and advantages of the invention. Modification of, and substitutions to, specific process conditions and structures can be made without departing from the spirit and scope of the invention. Accordingly, the invention is not to be considered as being limited by the foregoing description and drawings, but is only limited by the scope of the appended claims. | A transient index stack having an intermediate transient index layer, for use in an imaging device or a display device, that reduces reflection between layers having different refractive indexes by making a gradual transition from one refractive index to another. Other embodiments include a pixel array in an imaging or display device, an imager system having improved optical characteristics for reception of light by photosensors and a display system having improved optical characteristics for transmission of light by photoemitters. Enhanced reception of light is achieved by reducing reflection between a photolayer, for example, a photosensor or photoemitter, and surrounding media by introducing an intermediate layer with a transient refractive index between the photolayer and surrounding media such that more photons reach the photolayer. The surrounding media can include a protective layer of optically transparent media. | 7 |
BACKGROUND AND SUMMARY OF THE INVENTION
The present invention relates generally to an improved fishing reel, and more particularly to a spincast fishing reel having an improved feathering assembly.
In fishing, it is desirable to be able to selectively control the discharge of line from the spool during a cast to permit accurate placement of the line or bait. Control over such line feed or discharge is typically effected by applying a drag or frictional force to the line as it uncoils from the reel line spool. The contact with the uncoiling line is termed "feathering" and such feathering permits the fisherman to control the horizontal extent of his cast.
In an open face spinning reel, feathering is conventionally achieved by contacting the fishing line with one or more fingers of his casting hand. The fisherman gradually brings his finger(s) toward the line spool so that the line rubs against the finger and spool to apply a selective drag force to the uncoiling line. Similarly, in a bait casting fishing reel, where the line runs perpendicular to the axis of the reel and is exposed to the fisherman, he can feather his cast by applying his thumb to the spool as the line unwinds from it. This direct contact with the line permits the fisherman to "feel" the amount of pressure he applies to the line for feathering to control the horizontal extent of his cast.
However, spincast fishing reels are fishing reels in which a fishing line spool is contained within a reel housing. These reels typically having a thumb, or pushbutton, mechanism by which the fisherman can cast line from the reel. Direct contact between the fisherman and the line is impractical in a spincast fishing reel, largely because the reel cover which encloses the line spool is remote from the fisherman's hand. Additionally, the reel construction does not allow a fisherman to directly contact the line with his fingers to feather the line in the manner permitted by the spinning and bait casting reels described above.
Feathering has been previously accomplished in spincast reels by forcing the fishing line into contact with an object located on the rotor as the line unwinds from the line spool. The simplest spincast feathering devices have included a circular rubber friction ring affixed to the front face of the reel rotor. This friction ring is displaced with the rotor forwardly toward the reel cover when the spincast reel pushbutton is depressed. As it is displaced, the friction ring nears the inner surface of the reel cover and the line is captured between the friction ring and the interior surface of the reel cover. Contact with either or both of these elements induces a drag on the line by frictional contact which slows down the line during casting. However, this structure can often result in a sudden interruption of the travel of the line off of the line spool which causes the bait or line to be "jerked" rearwardly in flight. Accurate control is not possible using the braking ring above.
There have been some attempts to produce a reel structure having a feathering device which gives a greater degree of control of feathering during casting. One such structure is described in U.S. Pat. No. 3,185,405, issued May 25, 1965, to R. D. Hull which utilizes a wire loop protruding forwardly from the rotor to provide a single contact surface which contacts the line as it unwinds spirally from the line spool. However, because only one contact surface or point is presented in such a construction, the friction applied is not continuous and thus the feathering effect obtained is, at best, an intermittent one.
Another known feathering device is one manufactured by the Brunswick Corporation on its "Positive Pick Up System" closed face spinning reel. The feathering device consists of a circular rubber ring having a thin rubber skirt extruding forwardly of the rotor. The rotor is brought toward the reel housing by actuating a lever and the thin skirt engages the unwinding line and applies friction to it. Although this type of feathering device is continuous, there is not much "give" in the skirt and thus jerking of the line or bait still may occur.
The present invention is directed to providing a line feathering assembly for a spincast fishing reel having an improved feathering capability and which overcomes the disadvantages of the prior art feathering devices detailed above. The present invention utilizes a base member with a plurality of elongated, discrete, line engaging members axially affixed to the front surface of a rotor and thereby moves in unison with the rotor, either backwardly or forwardly, when the reel pushbutton is depressed. The line engaging members may include a plurality of fibers, hairs or bristles embedded in the base member in a circular pattern and extending angularly out from the base member to provide a circular interference profile to the fishing line as it unwinds from the line spool. The line engaging members are selectively brought into contact with the uncoiling line when the reel pushbutton is pressed to advance the rotor toward the reel cover. Rather than a single interference surface being presented to the fishing line, the bristles provide a plurality of discrete interference surfaces which cooperate to provide a continuous frictional contact to the line each of which deflects under contact with the line.
Accordingly, it is a general object of the present invention to provide an improved spincast fishing reel which includes a feathering device that selectively applies drag to the fishing line as it unwinds from the line spool.
Another object of the present invention is to provide a spincast fishing reel with a feathering device attached to the rotor thereof wherein the feathering device includes a plurality of fibers or bristles extruding outwardly from the rotorhead and which provide a plurality of contact surfaces circumferentially disposed around the rotor which provide interruptions with the line as it exits from the reel housing.
It is yet another object of the present invention to provide a feathering assembly for a spincast fishing reel wherein the assembly includes a rotor having a plurality of elongated discrete line engaging members extending outwardly therefrom toward the reel housing whereby, when the reel pushbutton is depressed, the discrete line engaging members approach the reel housing inner surface and present a series of sequential interference surfaces which frictionally interfere with the line as it unwinds from the line spool and exits from the reel.
It is still another object of the present invention to provide a feathering device for converting an existing spincast fishing reel without a feathering device into a spincast fishing reel having a means for feathering the line cast from it.
These and other objects, features and advantages of the present invention will be clearly understood through a consideration of the following detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
In the course of the following detailed description, reference will be frequently made to the accompanying drawings in which:
FIG. 1 is a perspective view of a spincast fishing reel exemplary of known spincast fishing reels;
FIG. 2 is a sectional view of the fishing reel of FIG. 1;
FIG. 3 is a perspective view of a rotor component having a feathering device exemplary of the prior art;
FIG. 4 is a sectional view of a portion of a conventional spincast fishing reel utilizing the feathering device assembly of FIG. 3;
FIG. 5 is a perspective view of a rotor component having a feathering device constructed in accordance with the principles of the present invention;
FIG. 5A is a sectional view of the rotor-feathering device assembly of FIG. 5 taken along lines 5--5;
FIG. 6 is a sectional view of the fishing reel of FIG. 2 with the rotor-feathering device assembly of FIG. 5 in place within the fishing reel of FIG. 1;
FIG. 7 is the same as FIG. 6 showing the position of the rotor-feathering device assembly when it is advanced within the reel housing;
FIG. 8 is a top sectional view of the fishing reel of FIG. 7; and
FIG. 9 is a diagrammatic view of the fishing reel of FIG. 7 as seen from the front of the reel with the reel housing removed.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIGS. 1 and 2, a conventional spincast fishing reel, generally designated 10, is shown. The reel 10 is conventional in that it contains a reel body member 12 and a removable reel cover member 14 which engages the reel body 12. The reel body 12 has a foot 16 for mounting the reel to a fishing rod. When assembled, the reel body 12 and cover 14 define an overall reel cavity 18 which contains the various mechanical components of the reel 10. A wall, or abutment 24, divides this cavity 18 into two separate smaller cavities, a reel rear gear cavity 26 and a forward spool cavity 28.
A shaft 20 extends through the wall 24 and is supported therein by a sleeve bearing 22. The bearing 22 permits both axial and rotatable movement of the shaft 20. A coil spring 30 is coaxially located on a rear portion of the shaft 20 and extends between a shaft enlarged end portion 32 and the rear face of between the rear face of a pinion gear 35. The coil spring 30 maintains the shaft 20 in an axial rearwardmost position. A rotor component 38 is affixed to the front end 21 of the shaft 20 by way of a nut 21. The rotor 38 has a front face 39 which opposes the inner surface 15 of the reel cover 14 as well as the reel line opening 13 associated therewith. A circular skirt portion 40 extends axially rearwardly from the rotor front face 39 and includes a line pickup pin 46 extending therefrom.
A reel drive gear 34 is rotatably mounted in the gear cavity 26 and is operatively connected to a reel handle assembly 36. The drive gear 34 drivingly engages the pinion gear 35 mounted on the shaft 20. Rotation of the drive gear 34 by the handle assembly 36 rotates the pinion gear 35 and shaft 20 which causes the rotor 38 to rotate around a line spool 40. Similarly, when the reel pushbutton 11 is pressed, a pushbutton engagement surface 17 bears against the shaft end 32 and causes displacement of the shaft 20 and its connected rotor 38 forwardly within the spool cavity 28.
The line spool 41 is mounted on the shaft 20 in the spool cavity 28, but is fixed in place within the cavity so as to prevent any rotation thereof. The line spool 41 has an annular channel 45 located between two opposing spool flanges 42, 43. This channel stores a desired length of fishing line 44 which is coiled around it. As is conventional, after the line is cast from the reel, the handle is turned to rotate the rotor and the line pick-up pin 46 engages the line 44 and coils it around the line spool 40 in the channel 45 during retrieval of the lure or bait. The rotor 38 may also include a rubber braking ring 48 located in its forward face 49 which can be urged forwardly with the rotor 38 against the reel housing inner surface 15 during casting to stop the line 44 from unwinding and stop the cast.
The foregoing structure has been previously known and is summarized to indicate the environment in which the present invention is intended to operate. As mentioned above, attempts in the past to provide a feathering device for such a spincast reel have included the use of a skirt extending from the rubber braking ring. Such a structure is shown in FIGS. 2 and 4, wherein the rotor 38 has a rubber braking ring 48 mounted thereon. The braking ring 48 has an axially extending skirt portion 60 which encircles the inner portion of the braking ring 48. In operation, when the line is cast by the fisherman, he can depress the pushbutton 11 which engages the reel shaft end portion 32 to move the rotor 38 forward, which permits line 44 to exit from the reel line opening 13. As the line 44 flies through the air, the fisherman may depress the pushbutton 11 further to move the rotor 38 and feathering skirt 60 closer to the inner surface 15 of the reel housing 44, as represented by the dotted line of FIG. 4. Theoretically, the line 44 rubs against the feathering skirt 60 which applies friction, or a drag to the line 44 and slows down the cast and reduces the length of the cast. However, because the skirt 60 is a continuous structure, the skirt 60 is not able to deflect in the direction of unwinding of the line 44 and jerking of the line or bait may result from an abrupt stopping of the line 44.
Turning now to FIG. 5, a feathering device, generally designated 100, constructed in accordance with the principles of the present invention, is shown in place upon a rotor 38. The feathering device 100 includes a generally circular base member 102 preferably constructed from a pliable material, such as rubber. The base member 102 has an interference means 104, having a plurality of discrete, elongated line engaging members 105, illustrated as bristles 106 axially extending outwardly from the rotor face 39 and base member 102 toward the inner surface 15 of the reel cover 14. The base member may have a generally conical configuration and preferably a frustoconical configuration, either of which are generally complementary to the contour of the reel cover inner surface 15.
The bristles 106 extend away from the base member 102 and, as such, the bristles 106 move forwardly and rearwardly in unison with the rotor 38 when pressure applied to or withdrawn from the pushbutton 11. As best shown in FIGS. 7 and 8, when the pushbutton 11 is depressed, the rotor 38 is moved forward within the spool cavity 28 and the bristles 106 are extended toward the reel cover inner surface 15. As the distance between the reel cover 14 and the rotor front face 39 closes, each bristle 106 presents a discrete line engagement or interference surface to the fishing line 44. As the line 44 uncoils from the line spool 41, the line 44 contacts the bristles 106, sequentially.
Because of the spacing between adjacent bristles 106, each bristle 106 applies a slight amount of friction or drag to the line 44. The spacing between bristles further permits each bristle 106 to deflect when it is contacted by the line 44 and thus the likelihood of abruptly stopping or snagging the uncoiling line 44 is reduced. The deflection of the bristles 106 by the line 44 will be greatest at the bristle tips 107 and will be less near the base 108 of the bristles 106. Thus, as the rotor 38 is moved closer to the reel cover inner surface 15, the amount of friction applied to the bristles 106 is increased. Thus, a fisherman can selectively control the feathering device 100 by increasing or decreasing the pressure on the reel pushbutton 11.
Preferred results have been obtained from the bristle arrangement of FIG. 9 where the bristles 106 are angled toward the center of the feathering device 100 as shown by θ 1 in FIG. 5A. Additionally, the bristles 106 can be arranged on the base member with a compound angle where they are not only angled toward the center of the base member 102 but also are angled at a second angle θ 2 (FIG. 8) in the direction in which the line 44 uncoils, shown clockwise in FIG. 9. The line engaging members 105 may be formed in a variety of ways. For example, they may be inserted individually into the base member 102 from either the front or rear faces thereof by way of a needle device, they may be molded in place with the base member 102, they may be inserted as pairs of individual strands or bristles or electrostatically flocked onto the base member 102. The bristles 106 may be formed from a variety of suitable resilient materials which have the ability to deflect when engaged by the fishing line 44. Such materials include rubber, natural fibers such as hemp and the like, synthetic materials such as plastic or even natural hair. Fine metal wire strands may also be used for the bristles provided they are resilient enough to deflect when contacted by the line and return to their original shape after the contact.
The configuration of the base member 102 may also define a braking surface 110 interior of the bristles 106. This braking surface 110 is similar in function to the conventional braking ring 48 described above in that it will contact the reel opening 13 when the pushbutton is completely depressed and the rotorhead 38 is displaced fully forwardly. To assist in the braking action of the base member 102, a frustoconical insert 112 (FIG. 7) may be present on the reel housing inner surface 15.
It has been found through use of the feathering device of the present invention that one is able to exert a greater degree of control on the feathering action during a cast than with the prior art device shown in FIGS. 3 and 4. This greater control is believed to be the result of the feathering device providing a plurality of discrete line engaging members each of which is free to deflect under contact by the fishing line, which mimics the application of friction by hand on a conventional spinning or baitcasting reel. The present invention virtually eliminates any occurrence of the line or bait "jerking" backward in flight when applied.
The preferred embodiments of the present invention have been shown and described for the purpose of illustration, not limitation. It will be understood that various changes and modifications may be made without departing from the true spirit and scope of the invention. | An improved spincast fishing reel includes a feathering assembly attached to the fishing reel rotor. The feathering assembly includes a plurality of line engaging members in the form of fibers or bristles angularly extending outwardly from the rotor into the space between the reel housing and the rotor. Each of these bristles present a surface which interferingly contacts the fishing line and are deflected by contact with the fishing line. When the line is cast, the fibers or bristles are moved into this contact with the line by actuation of the pushbutton on the reel. When so contacted, a feathering action is effected on the fishing line which may be selectively controlled by actuation of the thumb button. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application is a continuation of U.S. patent application Ser. No. 12/250,188, filed Oct. 13, 2008, now U.S. Pat. No. 8,220,457, which is a continuation of U.S. patent application Ser. No. 11/237,278, filed Sep. 28, 2005, which is a continuation of U.S. Pat. No. 6,988,498, issued Jan. 24, 2006, which is a continuation of U.S. Pat. No. 6,817,361, issued Nov. 16, 2004, which is a continuation of U.S. Pat. No. 6,502,572, issued Jan. 7, 2003, which is a continuation-in-part of U.S. Pat. No. 6,367,474, issued Apr. 9, 2002, which claims priority from Australian Application No. PP0269, filed Nov. 7, 1997, the disclosure of which is incorporated herein by reference.
FIELD OF THE INVENTION
This invention relates to the administration of continuous positive airway pressure (CPAP) treatment for partial or complete upper airway obstruction.
BACKGROUND OF THE INVENTION
In the Sleep Apnea syndrome a person stops breathing during sleep. Cessation of airflow for more than 10 seconds is called an “apnea”. Apneas lead to decreased blood oxygenation and thus to disruption of sleep. Apneas are traditionally (but confusingly) categorized as either central, where there is no respiratory effort, or obstructive, where there is respiratory effort. With some central apneas, the airway is open, and the subject is merely not attempting to breathe. Conversely, with other central apneas and all obstructive apneas, the airway is closed. The occlusion is usually at the level of the tongue or soft palate. The airway may also be partially obstructed (i.e., narrowed or partially patent). This also leads to decreased ventilation (hypopnea), decreased blood oxygenation and disturbed sleep.
The common form of treatment of these syndromes is the administration of Continuous Positive Airway Pressure (CPAP). The procedure for administering CPAP treatment has been well documented in both the technical and patent literature. An early description can be found in U.S. Pat. No. 4,944,310 (Sullivan). Briefly stated. CPAP treatment acts as a pneumatic splint of the airway by the provision of a positive pressure usually in the range 4-20 cm H 2 0. The air is supplied to the airway by a motor driven blower whose outlet passes via an air delivery hose to a nose (or nose and/or mouth) mask sealingly engaged to a patient's face. An exhaust port is provided in the delivery tube proximate to the mask. The mask can take the form of a nose and/or face mask or nasal prongs, pillows or cannulae.
Various techniques are known for sensing and detecting abnormal breathing patterns indicative of obstructed breathing. U.S. Pat. No. 5,245,995 (Sullivan et al.), for example, generally describes how snoring and abnormal breathing patterns can be detected by inspiration and expiration pressure measurements made while a subject is sleeping, thereby leading to early indication of preobstructive episodes or other forms of breathing disorder. Particularly, patterns of respiratory parameters are monitored, and CPAP pressure is raised on the detection of pre-defined patterns to provide increased airway pressure to, ideally, subvert the occurrence of the obstructive episodes and the other forms of breathing disorder.
Automatic detection of partial upper airway obstruction and pre-emptive adjustment of nasal CPAP pressure works to prevent frank obstructive apneas in the majority of subjects with obstructive sleep apnea syndrome. However, some subjects with severe disease progress directly from a stable open upper airway to a closed airway apnea with complete airway closure, with little or no intervening period of partial obstruction. Therefore it is useful for an automatically adjusting CPAP system to also respond to a closed airway apnea by an increase in CPAP pressure. However, it is not desirable to increase CPAP pressure in response to open airway apneas, firstly because this leads to an unnecessarily high pressure and secondly because the high pressure can reflexly cause yet further open airway apneas, leading to a vicious circle of pressure increase.
One method for distinguishing open airway apneas (requiring no increase in pressure) from closed airway apneas (requiring a pressure increase) is disclosed in commonly owned European Publication No. 0 651 971 A1 (corresponding to U.S. Pat. No. 5,704,345). During an apnea, the mask pressure is modulated at 4 Hz with an amplitude of the order of 1 cmH 2 0, the induced airflow at 4 Hz is measured, and the conductance of the airway is calculated. A high conductance indicates an open airway. This ‘forced oscillation method’ requires the ability to modulate the mask pressure at 4 Hz, which increases the cost of the device. Furthermore, the method does not work in the presence of high leak, and can falsely report that the airway is closed if the subject has a high nasal or intrapulmonary resistance.
The present invention is directed to overcoming or at least ameliorating one or more of the foregoing disadvantages in the prior art.
BRIEF SUMMARY OF THE INVENTION
Therefore, the invention discloses a method for the administration of CPAP treatment pressure comprising the steps of:
supplying breathable gas to the patient's airway at a treatment pressure;
determining a measure of respiratory airflow; and
determining the occurrence of an apnea from a reduction in the measure of respiratory airflow below a threshold, and, if having occurred
(i) determining the duration of the apnea; and
(ii) increasing the treatment pressure by an amount which is an increasing function of the duration of the apnea, and a decreasing function of the treatment pressure immediately before the apnea.
The invention further discloses CPAP treatment apparatus comprising:
a controllable flow generator operable to produce breathable gas at a pressure elevated above atmosphere;
a gas delivery tube coupled to the flow generator;
a patient mask coupled to the tube to receive said breathable gas from the flow generator and provide said gas, at a desired treatment pressure, to the patient's airway;
a controller operable to receive input signals and to control operation of said flow generator and hence the treatment pressure; and
sensor means located to sense patient respiratory airflow and generate a signal input to the controller from which patient respiratory airflow is determined;
and wherein said controller is operable to determine the occurrence of an apnea from a reduction in said respiratory airflow below a threshold, and if having occurred, to determine the duration of said apnea and cause said flow generator to increase CPAP treatment pressure by an amount that is an increasing function of said apnea duration, and a decreasing function of the treatment pressure immediately prior to said apnea.
The invention yet further provides CPAP treatment apparatus comprising:
a controllable flow generator operable to produce breathable gas to be provided to a patient at a treatment pressure elevated above atmosphere; and
a controller operable to receive input signals representing patient respiratory airflow, and to control operation of said flow generator and hence the treatment pressure;
and wherein said controller is operable to determine the occurrence of an apnea
from a reduction in said respiratory airflow below a threshold, and, if having occurred,
to determine the duration of said apnea and cause said flow generator to increase CPAP
treatment pressure by an amount that is an increasing function of said apnea duration, and a decreasing function of the treatment pressure immediately prior to said apnea.
Preferably, the increase in treatment pressure is zero if the treatment pressure before the apnea exceeds a pressure threshold. The increase in pressure below the pressure threshold can be an increasing function of the duration of the apnea, multiplied by the difference between the pressure threshold and the current treatment pressure. Further, the increasing function of apnea duration is linear on apnea duration. Advantageously, said increasing function of apnea duration is zero for zero apnea duration, and exponentially approaches an upper limit as apnea duration goes to infinity.
The occurrence of an apnea can be determined by calculating the RMS respiratory airflow over a short time interval, calculating the RMS respiratory airflow over a longer time interval, and declaring an apnea if the RMS respiratory airflow over the short time interval is less than a predetermined fraction of the RMS respiratory airflow over the longer time interval. There also can be the further step or action of reducing the treatment pressure towards an initial treatment pressure in the absence of a further apnea.
In a preferred form, said sensor means can comprise a flow sensor, and said controller derives respiratory airflow therefrom.
In one preferred form said initial treatment pressure is 4 cmH 2 O, said measure of respiratory airflow is the 25% of the RMS airflow over the preceding 5 minutes. In this preferred form no increase in pressure is made for apneas of less than 10 seconds duration, or for apneas where the treatment pressure immediately prior to the apnea is more than cmH 2 O, but otherwise, the lower the treatment pressure immediately prior to the apnea, and the longer the apnea, the greater the increase in treatment pressure, up to a maximum of 8 cmH 2 O per minute of apnea. In this preferred form, if there is no apnea the treatment pressure is gradually reduced towards the initial minimum pressure with a time constant of 20 minutes.
The method and apparatus can advantageously be used in concert with one or more other methods for determining the occurrence of partial upper airway obstruction, such that either complete or partial upper airway obstruction can lead to an increase in pressure, but once there is no longer either complete or partial obstruction, the pressure will gradually reduce towards the initial minimum pressure.
In one particularly preferred form, partial obstruction is detected as either the presence of snoring, or the presence of characteristic changes in the shape of the inspiratory flow-vs-time curve indicative of inspiratory airflow limitation.
The method and apparatus can also advantageously be used in concert with the ‘forced oscillation method’ for measuring airway patency (referred to above as European Publication No. 0 651 971 A1, U.S. Pat. No. 5,704,345 whose disclosure is hereby incorporated by reference), in which the CPAP pressure is modulated with an amplitude of for example 1 cm H 2 O at 4 Hz, the induced airflow at 4 Hz is measured, the conductance of the airway calculated by dividing the amplitude of the induced airflow by the pressure modulation amplitude, and the additional requirement imposed that the treatment pressure is only increased if said conductance is greater than a threshold.
Closed airway apneas are most likely to occur at low CPAP pressures, because high CPAP pressures splint the airway partially or completely open whereas pressure-induced open airway apneas are most likely to occur at high CPAP pressures, at least partially because high CPAP pressures increase lung volume and thereby stimulate the Hering-Breuer reflex, leading to inhibition of breathing. Therefore, the lower the existing CPAP pressure, the more likely an apnea is to be of the closed airway variety, and the more appropriate it is to increase the treatment pressure, whereas the higher the existing CPAP pressure, the more likely an apnea is to be of the open airway variety, and the more appropriate it is to leave the CPAP pressure unchanged. Generally apneas of less than 10 seconds duration are regarded as non-pathological, and there is no need to increase CPAP pressure, whereas very long apneas require treatment. The present invention will correctly increase the CPAP pressure for most closed airway apneas, and correctly leave the CPAP pressure unchanged for most open airway apneas.
The present invention can be combined with an independent pressure increase in response to indicators of partial upper airway obstruction such as snoring or changes in shape of the inspiratory flow-time curve. In this way it is possible in most subjects to achieve pre-emptive control of the upper airway, with pressure increases in response to partial upper airway obstruction preventing the occurrence of closed airway apneas. In the minority of subjects in whom pre-emptive control is not achieved, this combination will also correctly increase the CPAP pressure in response to those closed airway apneas that occur at low CPAP pressure without prior snoring or changes in the shape of the inspiratory flow-time curve. Furthermore, the combination will avoid falsely increasing the CPAP pressure in response to open airway apneas induced by high pressure.
Some open airway apneas can occur at low pressure. By combining the forced oscillation method with the present invention, with the additional requirement that there be no increase in pressure if the forced oscillation method detects an open airway, false increases in pressure in response to open airway apneas at low pressure will be largely avoided.
BRIEF DESCRIPTION OF THE DRAWINGS
Embodiments of the invention will now be described with reference to the accompanying drawings, in which:
FIG. 1 shows, in diagrammatic form, apparatus embodying the invention;
FIG. 2 shows an alternative arrangement of the apparatus of FIG. 1 ;
FIG. 3 shows a plot of two pressure change characteristics as a function of apnea duration;
FIG. 4 shows a plot of the apnea duration function;
FIG. 5 shows a graph of CPAP treatment pressure versus time for a preferred embodiment of the invention; and
FIG. 6 shows a graph of scaled (normalized) air flow with time for normal and partially obstructed inspiration.
DETAILED DESCRIPTION
FIG. 1 shows, in diagrammatic form, CPAP apparatus in accordance with one embodiment. A mask 30 , whether either a nose mask and/or a face mask, is sealingly fitted to a patient's face. Breathable gas in the form of fresh air, or oxygen enriched air, enters the mask 30 by flexible tubing 32 which, in turn is connected with a motor driven turbine 34 to which there is provided an air inlet 36 . The motor 38 for the turbine is controlled by a motor-servo unit 40 to commence, increase or decrease the pressure of air supplied to the mask 30 as CPAP treatment. The mask 30 also includes an exhaust port 42 that is close to the junction of the tubing 34 with the mask 30 .
Interposed between the mask 30 and the exhaust 42 is a linear flow-resistive element 44 . In practice, the distance between mask 30 and exhaust 42 , including flow resistive element 44 is very short so as to minimize deadspace volume. The mask side of the flow-resistive element 44 is connected by a small bore tube 46 to a mask pressure transducer 48 and to an input of a differential pressure transducer 50 . Pressure at the other side of the flow-resistive element 44 is conveyed to the other input of the differential pressure transducer 50 by another small bore tube 52 .
The mask pressure transducer 48 generates an electrical signal in proportion to the mask pressure, which is amplified by amplifier 53 and passed both to a multiplexer/ADC unit 54 and to the motor-servo unit 40 . The function of the signal provided to the motor-servo unit 40 is as a form of feedback to ensure that the actual mask static pressure is controlled to be closely approximate to the set point pressure.
The differential pressure sensed across the linear flow-resistive element 44 is output as an electrical signal from the differential pressure transducer 50 , and amplified by another amplifier 56 . The output signal from the amplifier 56 therefore represents a measure of the mask airflow. The linear flow-resistive element 44 can be constructed using a flexible-vaned iris. Alternatively, a fixed orifice can be used, in which case a linearization circuit is included in amplifier 53 , or a linearization step such as table lookup included in the operation of controller 62 .
The output signal from the amplifier 56 is low-pass filtered by the low-pass filter 58 , typically with an upper limit of 10 Hz, in order to remove non-respiratory noise. The amplifier 56 output signal is also bandpassed by the bandpass filter 60 , and typically in a range of 30-100 Hz to yield a snoring signal. The outputs from both the low-pass filter 58 and the bandpass filter 60 are provided to the digitizer (ADC) unit 54 . The digitized respiratory airflow (FLOW), snore, and mask pressure (P.sub.mask) signals from ADC 54 are passed to a controller 62 typically constituted by a micro-processor based device also provided with program memory and data processing storage memory.
The controller 62 outputs a pressure request signal which is converted to a voltage by DAC 64 , and passed to the motor-servo unit 40 . This signal therefore represents the set point pressure P.sub.set(t) to be supplied by the turbine 34 to the mask 30 in the administration of CPAP treatment. The controller 62 is programmed to perform a number of processing functions, as presently will be described.
As an alternative to the mask pressure transducer 48 , a direct pressure/electrical solid state transducer (not shown) can be mounted from the mask with access to the space therewithin, or to the air delivery tubing 32 proximate the point of entry to the mask 30 .
Further, it may not be convenient to mount the flow transducer 44 at or near the mask 30 , nor to measure the mask pressure at or near the mask. An alternative arrangement, where the flow and pressure transducers are mounted at or near the air pressure generator (in the embodiment being the turbine 34 ) is shown in FIG. 2 .
The pressure p.sub.g(t) occurring at the-pressure generator 34 outlet is measured by a pressure transducer 70 . The flow f.sub.g(t) through tubing 32 is measured with flow sensor 72 provided at the output of the turbine 34 . The pressure loss along tubing 32 is calculated in element 74 from the flow through the tube f.sub.g(t), and a knowledge of the pressure-flow characteristic of the tubing, for example by table lookup. The pressure at the mask p.sub.m is then calculated in subtraction element 76 by subtracting the tube pressure loss from p.sub.g(t).
The pressure loss along tube 32 is then added to the desired set pressure at the mask p.sub.set(t) in summation element 78 to yield the desired instantaneous pressure at the pressure generator 34 . Preferably, the controller of the pressure generator 34 has a negative feedback input from the pressure transducer 70 , so that the desired pressure from step 78 is achieved more accurately. The flow through the exhaust 42 is calculated from the pressure at the mask (calculated in element 76 ) from the pressure-flow characteristic of the exhaust in element 80 , for example by table lookup. Finally, the mask flow is calculated by subtracting the flow through the exhaust 42 from the flow through the tubing 32 , in subtraction element 82 .
The methodology put into place by the controller 62 will now be described. In a first embodiment, there is a pressure response to apneas, but not to indicators of partial obstruction, and therefore snore detection bandpass filter 60 is not required.
An initial CPAP treatment pressure, typically 4 cmH.sub.2O, is supplied to the subject. The FLOW signal is processed to detect the occurrence of an apnea (as will presently be discussed) and, at the same time the P.sub.mask signal is recorded. When it is determined that an apnea has occurred its duration is recorded. At the same time P.sub.mask is compared against a pressure threshold, P.sub.u. If P.sub.mask is at or above P.sub.u the controller will act to maintain or reduce that pressure. If, on the other hand, P.sub.mask is below P.sub.u, the controller will act to increase the treatment pressure by an amount .DELTA.P.
In a preferred form, .DELTA.P is determined as follows
.DELTA. P=[P .sub. u−P]f ( t .sub. a ) (1)
where .DELTA.P is the change in pressure (cmH.sub.2O) P.sub.u is the pressure threshold, which in an embodiment can be 10 cmH.sub.2O P is the current treatment pressure immediately before the apnea (cmH.sub.2O) t.sub.a is the apnea duration(s)
f(t.sub.a) is a function that is a monotonically increasing function of t.sub.a, zero for t.sub.a=0
FIG. 3 is a graphical representation of equation (1), showing a region below P.sub.u where it is taken that an apnea is obstructive and demonstrating two cases of the .DELTA.P characteristic as a function of apnea duration (i.e., short and longer) such that .DELTA.P is an increasing function of apnea duration and a decreasing function of the current treatment pressure. Above P.sub.u, it is taken that the apnea is non-obstructive, and .DELTA.P is held to be zero for all values of the current treatment pressure.
One form of the function f(t.sub.a) is:
1 f ( ta )= rtaP max (2)
In one embodiment the parameters can be:
r=0.13 cmH.sub.2O.s.sup.−1
.DELTA.P.sub.max=6 cmH.sub.2O
Another form of the function f(t.sub.a) is:
f ( t .sub. a )=1−exp(− kt .sub. a ) (3)
In one embodiment the parameter can be k=0.02 s.sup.−1
FIG. 4 is a graphical representation of equation (3) for the parameters given above.
The controller 62 implements the foregoing methodology using the following pseudo-code.
Set apnea duration to zero
Clear “start of breath” flag
Set initial CPAP pressure to 4 cmH.sub.2O.
Set maximum delta pressure due to apnea to 6 cmH.sub.2O.
Set top roll-off pressure to initial CPAP pressure plus maximum delta pressure due to apnea.
REPEAT
Sample mask airflow (in L/sec) at 50 Hz.
Calculate mask leak as mask airflow low pass filtered with a time constant of 10 seconds.
Check for presence and duration of any apnea
Check for start of breath.
IF start of breath flag set:
IF apnea duration greater than 10 seconds AND current CPAP pressure less than top roll-off pressure:
Set delta pressure for this apnea to (top roll-off pressure—current CPAP pressure)/maximum delta pressure due to apnea times 8 cmH.sub.2O per minute of apnea duration.
Add delta pressure for this apnea to total delta pressure due to apnea, and truncate to maximum delta pressure due to apnea.
Reset apnea duration to zero.
ELSE
Reduce total delta pressure due to apnea with a time constant of 20 minutes.
End
Set CPAP pressure to initial CPAP pressure plus total delta pressure due to apnea.
Clear start of breath flag.
END
END
This implementation is suitable for subjects in whom obstructive apneas are controlled at a CPAP pressure of less than 10 cmH.sub.2O. Increasing the maximum delta pressure due to apnea from 6 cmH.sub.2O to 10 cmH.sub.2O would permit the prevention of obstructive apneas in the majority of subjects, in exchange for an increase in undesirable pressure increases due to open airway apneas.
The procedure “Check for presence and duration of any apnea” can be implemented using the following pseudocode:
Calculate 2 second RMS airflow as the RMS airflow over the previous 2 seconds.
Calculate long term average RMS airflow as the 2 second RMS airflow, low pass filtered with a time constant of 300 seconds.
IF 2 second RMS airflow is less than 25% of long term average RMS airflow:
Mark apnea detected and increment apnea duration by 1/50 second.
END
The procedure, “Check for start of breath” is implemented by the following pseudocode:
IF respiratory airflow is inspiratory AND respiratory airflow on previous sample was not inspiratory.
Set “start of breath” flag.
END
FIG. 5 shows the above method and apparatus in operation. The mask 30 was connected to a piston driven breathing simulator set to a normal respiratory rate and depth, and programmed to introduce a 20 second apnea once per minute from the 2nd minute to the 20th minute. In operation, the pressure remained at the initial pressure of 4 cmH.sub.2O until the first apnea, which led to a brisk increase in mask pressure. The pressure then decayed slightly during the subsequent 40 seconds of normal breathing.
Subsequent apneas produced smaller increments, and the mask pressure settled out to approximately 9.5 cmH.sub.2O. In most actual patients, the number of apneas would reduce as the pressure increased. Because the pressure due to repetitive apneas cannot exceed 10 cmH.sub.2O, and most pressure-induced open airway apneas occur at very high pressures typically above 10 cmH.sub.2O, this algorithm will not falsely or needlessly increase pressure in response to most pressure-induced open airway apneas, thus avoiding a vicious cycle of high pressure leading to open airway apneas leading to yet further pressure increase.
The above embodiment can be considerably improved by the addition of independent pressure increases in response to partial upper airway obstruction indicated by the presence of snoring or changes in the shape of the inspiratory flow-vs-time curve. In the majority of subjects, in whom substantial periods of snoring or flow limitation exist prior to any closed airway apneas, the CPAP pressure will increase in response to said snoring and/or changes in the shape of the inspiratory flow-vs-time curve, to a sufficient level to largely eliminate severe partial obstruction, without any apneas of any kind occurring. In those subjects in whom closed airway apneas appear with little or no prior period of partial obstruction, the first few apneas will produce a brisk increase in CPAP pressure as previously discussed, and in general this will provide sufficient partial support to the airway to permit periods of detectable partial obstruction, preventing any further apneas from occurring.
This second embodiment is implemented using the following pseudocode.
Set initial CPAP pressure to 4 cmH.sub.2O.
Set apnea duration to zero
Clear “start of breath” flag
REPEAT every 1/50 of a second
Sample mask pressure (in cmH.sub.2O), mask airflow (in L/sec), and snore (1 unit corresponds loosely to a typical snore).
Calculate mask leak as mask airflow low pass filtered with a time constant of 10 seconds.
Adjust snore signal for machine noise.
Check for presence and duration of any apnea.
Check for start of breath.
IF start of breath flag set:
IF apnea duration greater than 10 seconds AND current CPAP pressure less than 10 cmH.sub.2O:
Set delta pressure for this apnea to (10—current CPAP pressure)/6 times 8 cmH.sub.2O per minute of apnea duration.
Add delta pressure for this apnea to total delta pressure due to apnea, and truncate to 16 cmH.sub.2O
Reset apnea duration to zero.
ELSE
Reduce total delta pressure due to apnea with a time constant of 20 minutes.
END
Calculate flow limitation index.
Calculate flow limitation threshold.
IF flow limitation index is less than said threshold:
Set flow limitation delta pressure for this breath to 3 cmH.sub.2O times (threshold-flow limitation index).
Add flow limitation delta pressure for this breath to total delta pressure due to flow limitation, and truncate to 16 cmH.sub.2O.
ELSE
Reduce total delta pressure due to flow limitation with a time constant of 10 minutes.
END
Calculate mean snore for breath.
Calculate snore threshold.
IF mean snore exceeds said threshold: set delta pressure due to snore for this breath to 3 cmH.sub.2O times (mean snore for this breath—threshold).
Add delta pressure due to snore for this breath to total delta pressure due to snore, and truncate to 16 cmH.sub.2O.
ELSE
Reduce total delta pressure due to snore with a time constant of 10 minutes.
END
Set CPAP pressure to 4 cmH.sub.2O plus total delta pressure due to apnea plus total delta pressure due to snore plus total delta pressure due to flow limitation, and truncate to 20 cmH.sub.2O.
Clear start of breath flag.
END
END
In the above implementation, apneas can only cause the CPAP pressure to rise as far as 10 cmH.sub.2O, but subsequently, indicators of partial obstruction can increase the CPAP pressure to 20 cmH.sub.2O, which is sufficient to treat the vast majority of subjects.
The procedure “Adjust snore for machine noise” is described by the following pseudocode
Machine noise=K1*mask pressure+K2*mask pressure squared+K3*mask flow+K4*time derivative of mask flow+K5*time derivative of mask pressure.
Adjusted snore signal=raw snore signal-machine noise.
where the constants K1 to K5 are determined empirically for any particular physical embodiment, and for a particular machine may be zero. In other embodiments, blower fan speed measured with a tachometer or pressure at the blower may be used instead of mask pressure.
The procedure “Calculate flow limitation index” is described by the following pseudocode:
Identify the inspiratory portion of the preceding breath
Note the duration of inspiration.
Calculate the mean inspiratory airflow.
For each sample point over said inspiratory portion, calculate a normalized inspiratory airflow by dividing the inspiratory airflow by the mean inspiratory airflow.
Identify a mid-portion consisting of those sample points between 25% and 75% of the duration of inspiration.
Calculate the flow limitation index as the RMS deviation over said mid-portion of (normalized inspiratory airflow-1)
The logic of the above algorithm is as follows: partial upper airway obstruction in untreated or partially treated Obstructive Sleep Apnea syndrome, and the related Upper Airway Resistance syndrome, leads to mid-inspiratory flow limitation, as shown in FIG. 6 , which shows typical inspiratory waveforms respectively for normal and partially obstructed breaths after scaling (normalizing) to equal mean amplitude and duration.
For a totally flow-limited breath, the flow amplitude vs. time curve would be a square wave and the RMS deviation would be zero. For a normal breath, the RMS deviation is approximately 0.2 units, and this deviation decreases as the flow limitation becomes more severe.
In some patients, it is not possible to prevent all upper airway obstruction, even at maximum pressure. In addition, there is a trade-off between the possible advantage of increasing the pressure in response to snoring and the disadvantage of increased side effects. This trade-off is implemented in procedure “calculate snore threshold” by looking up the snore threshold in the following table:
1 Pressure Threshold (cmH.sub.2O) (snore units) Description <10 0.2 very soft 10-12 0.25 12-14 0.3 soft 14-16 0.4 16-18 0.6 moderate >18 1.8 loud
For similar reasons, the procedure “calculate flow limitation threshold” sets the flow limitation threshold to a lower value corresponding to more severe flow limitation, if the pressure is already high or if there is a large leak:
IF mask leak is greater than 0.7 L/sec
set leak roll-off to 0.0
ELSE if mask leak is less than 0.3 L/sec
set leak roll-off to 1.0
ELSE
set leak roll-off to (0.7-mask leak)/0.4
END
Set pressure roll-off to (20-mask pressure)/16
Set flow limitation threshold to 0.15 times pressure roll-off times leak roll-off
Some subjects will have occasional open airway apneas at sleep onset during stage 1 sleep and therefore at low pressure, and the above algorithm will incorrectly increase CPAP pressure in response to these events. However, such apneas are not usually repetitive, because the subject quickly becomes more deeply asleep where such events do not occur, and furthermore, the false pressure increments become smaller with repeated events. Once the subject reaches deeper sleep, any such falsely increased pressure will diminish. However, it is still advantageous to avoid falsely or needlessly increasing pressure in response to such sleep onset open airway apneas.
As previously discussed, one prior art method for avoiding unnecessary increases in pressure in response to open airway apneas is to determine the conductance of the airway during an apnea using the forced oscillation method, and only increase mask pressure if the conductance is less than a threshold. However, if the nasal airway is narrow or if the subject has lung disease, the airway conductance may be low even in the presence of an open airway and the forced oscillation method may still falsely increase pressure in response to open airway apneas. Conversely, the combination of the forced oscillation method with embodiments of the present invention has the added advantage that in most cases open airway apneas are correctly detected by the ‘forced oscillation method’, but in those cases where the forced oscillation method falsely reports a closed airway, the mask pressure will not increase above 10 cmH.sub.2O, thus preventing run-away increases in pressure. This is demonstrated in a third embodiment using the following pseudo-code:
Set apnea duration to zero
Clear “start of breath” flag
REPEAT every 1/50 of a second
Sample mask pressure (in cmH20), mask airflow (in L/sec), and snore (1 unit corresponds loosely to a typical snore).
Calculate mask leak as mask airflow low pass filtered with a time constant of 10 seconds.
Adjust snore signal for machine noise.
Check for presence and duration of any apnea.
IF apnea in progress:
measure conductance of airway using forced oscillation method.
END
Check for start of breath.
IF start of breath flag set:
IF apnea duration greater than 10 seconds AND current CPAP pressure less than 10 cmH.sub.2O AND airway conductance measured using forced oscillation method is less than 0.05 cmH.sub.2O/L/sec:
Set delta pressure for this apnea to (10—current CPAP pressure)/6 times 8 cmH.sub.2O per minute of apnea duration.
Add delta pressure for this apnea to total delta pressure due to apnea, and truncate to 16 cmH.sub.9O
Reset apnea duration to zero.
ELSE
Reduce total delta pressure due to apnea with a time constant of 20 minutes.
END
Calculate flow limitation index.
Calculate flow limitation threshold.
IF flow limitation index is less than said threshold:
Set flow limitation delta pressure for this breath to 3 cmH.sub.2O times (threshold-flow limitation index).
Add flow limitation delta pressure for this breath to total delta pressure due to flow limitation, and truncate to 16 cmH.sub.2O.
ELSE
Reduce total delta pressure due to flow limitation with a time constant of 10 minutes.
END
Calculate mean snore for breath.
Calculate snore threshold.
IF mean snore exceeds said threshold:
set delta pressure due to snore for this breath to 3 cmH.sub.2O times (mean snore for this breath—threshold).
Add delta pressure due to snore for this breath to total delta pressure due to snore, and truncate to 16 cmH.sub.2O.
ELSE
Reduce total delta pressure due to snore with a time constant of 10 minutes.
END
Set CPAP pressure to 4 cmH.sub.2O plus total delta pressure due to apnea plus total delta pressure due to snore plus total delta pressure due to flow limitation, and truncate to 20 cmH.sub.2O.
Clear start of breath flag.
END
END
The procedure, “measure airway conductance using the forced oscillation method” can be implemented using the following pseudocode:
Modulate airway pressure with an amplitude of 1 cmH.sub.2O peak to peak at 4 Hz.
Measure amplitude of airflow signal at 4 Hz.
Measure component of mask pressure signal at 4 Hz.
Set conductance equal to said airflow amplitude divided by said mask pressure amplitude.
An alternate expression of the combination of an embodiment of the invention and the forced oscillation method is:
IF
(a) the current pressure is low AND (b) the alternative method scores the airway as closed, THEN score the airway as closed.
ELSE IF
(a) the current pressure is high AND (b) the alternative method scores the airway as open, THEN score the airway as open.
ELSE
score the apnea as of unknown type.
A further possible arrangement is to substitute the ‘cardiogenic method’ for determining airway patency for the ‘forced oscillation method’, also disclosed in European Publication No. 0 651 971 A1 (and U.S. Pat. No. 5,704,345).
More complex variants of CPAP therapy, such as bi-level CPAP therapy or therapy in which the mask pressure is modulated within a breath, can also be monitored and/or controlled using the methods described herein.
Although the invention herein has been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present invention. It is therefore to be understood that numerous modifications may be made to the illustrative embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended claims. | CPAP treatment apparatus is disclosed having a controllable flow generator ( 34, 38, 40 ) operable to produce breathable gas at a treatment pressure elevated above atmosphere to a patient by a delivery tube ( 32 ) coupled to a mask ( 30 ) having connection with a patient's airway. A sensor ( 44, 50, 56, 58 ) generates a signal representative of patient respiratory flow, that is provided to a controller ( 54, 62, 64 ). The controller ( 54 , pressure. In one preferred form the increase in pressure is zero if the treatment pressure before the apnea exceeds a pressure threshold. Below the pressure threshold the increase in pressure is an increasing function of the duration of the apnea multiplied by the difference between the pressure threshold and the current treatment pressure. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
Not Applicable
STATEMENT RE: FEDERALLY SPONSORED RESEARCH/DEVELOPMENT
Not Applicable
BACKGROUND
1. Technical Field
The present invention generally relates to concrete structures and the methods for forming the same. More particularly, the present invention relates to concrete structures and forming methods that enhance the replenishment of underground water in aquifers.
2. Description of Related Art
As is generally understood, a common source of fresh water for irrigation, human consumption, and other uses is groundwater. Usable groundwater is contained in aquifers, which are subterranean layers of permeable material such as sand and gravel that channel the flow of the groundwater. Other forms of groundwater include soil moisture, frozen soil, immobile water in low permeability bedrock, and deep geothermal water. Among the methods utilized to extract groundwater include drilling wells down to the water table, as well as removing it from springs where an aquifer intersects with the curvature of the surface of the earth.
While groundwater extraction methods are well known, much consideration has not been given to the replenishment thereof. It is not surprising that many aquifers are being overexploited, significantly depleting the supply. The most typical method of aquifer replenishment is through natural means, where precipitation on the land surface is absorbed into the soil and filtered through the earth before reaching the aquifer. However, in arid and semi-arid regions, the supply cannot be renewed as rapidly as it is being withdrawn because the natural process takes years, even centuries, to complete. It is well understood that in its equilibrium state, groundwater in aquifers support some of the weight of the overlying sediments. When aquifers are depressurized or depleted, the overall capacity is decreased, and subsidence may occur. In fact, such subsidence that occurs because of depleted aquifers is partially the reason why some cities, such as New Orleans in the state of Louisiana in the United States, are below sea level. It is well recognized that such low-lying and subsided areas have many attendant public safety and welfare problems, particularly when flooding or other like natural disasters occur.
The problem of rapid depletion is particularly compounded in developed areas such as cities and towns, where roads, buildings, and other man-made structures block the natural absorption of precipitation through permeable soil. Generally, building and paving materials such as concrete and asphalt are not porous, in that water cannot move through the material and be absorbed into the soil. In fact, porous material would be unsuitable for construction of buildings, where internal moisture is desirably kept to a minimum. Thus, these developed areas are typically engineered with storm drainage systems whereby precipitation is channeled to a central location, marginally cleaned of debris, bacteria, and other elements harmful to the environment which were picked up along the drainage path, and carried out to the sea. Instead of allowing precipitation to absorb into the ground, modern developed areas transport almost all surface water elsewhere.
One of the methods for replenishing aquifers is described in U.S. Pat. No. 6,811,353 to Madison, which teaches a valve assembly for attachment to aquifer replenishment pipes. However, the use of such replenishment systems required frequent human intervention. Furthermore, in order for the water in the aquifer to remain clean, existing clean water had to be pumped in. Additionally, the volume of water that was able to be carried to these re-charging locations was limited, thus limiting the replenishment capacity.
Changes to paving materials have also been considered. As is well known in the art, concrete is a composite material made from aggregate and a cement binder, the most common form of concrete being Portland cement concrete. The mixture is fluid in form before curing, and after pouring, the cement begins to hydrate and gluing the other components together, resulting in a relatively impermeable stone-like material. By eliminating the aggregate of gravel and sand, the concrete formed miniature holes upon curing, resulting in porous concrete. This form of concrete, while allowing limited amounts of water to pass through, was unsuitable for paving purposes because of its reduced strength. Additionally, the aforementioned drainage systems were still required because the porous concrete was unable to handle all of the water in a typical rainfall. Structures designed to increase the strength while maintaining porosity have been attempted, whereby reinforcement in the form of rods, rebar, and/or fibers were incorporated into the structure. Nevertheless, the strength of the structure was insufficient because of the reduced internal bonding force of the concrete due to the lack of an aggregate.
Therefore, there is a need in the art for an aquifer replenishment system for collecting precipitation and absorbing the same into the pavement and the soil in the immediate vicinity. There is also a need for aquifer replenishment system that are capable of withstanding environmental stresses such as changes in temperature, as well as structural stresses such as those associated with vehicle travel. Furthermore, there is a need for an aquifer replenishment system that can be retrofitted into existing pavement structures.
BRIEF SUMMARY
In light of the foregoing problems and limitations, the present invention was conceived. In accordance with one embodiment of the present invention, an aquifer replenishing pavement is provided, which lies above soil having a sand lens above an aquifer, and a clay layer above the sand lens. The structure is comprised of: an aggregate leach field abutting the subgrade (typically comprised of clay); and a layer of suitable surface paving material such as reinforced concrete or asphalt, abutting the aggregate leach field. Additionally, one or more surface drains extend through the concrete layer, and one or more aggregate drains extend from the aggregate leach field to the sand lens. The surface drains have a higher porosity than the paving layer, and is filled with rocks. According to another aspect of the invention, leach lines having a higher porosity than the surrounding leach field are provided. The surface drains are in direct fluid communication with the leach lines, and the leach lines are in direct fluid communication with the aggregate drains.
An aquifer replenishing concrete paving method is also provided, comprising the steps of: (a) clearing and removing a top soil layer until reaching a clay layer; (b) forming one or more aggregate drains through the clay layer to a sand lens; (c) forming an aggregate leach field above the clay layer; (d) forming a pavement layer above the aggregate leach field; and (e) forming surface drains extending the entire height of the pavement layer. Additionally, forming of the aggregate leach field also includes the step of forming one or more leach lines therein.
In accordance with another embodiment of the present invention, an aquifer replenishing concrete gutter for use on a road surface with an elevated curb section is provided. The gutter is comprised of a porous concrete section having an exposed top surface in a co-planar relationship with the road surface, supported by the elevated curb section and the side surface of the road. According to another aspect of the present invention, a cut-off wall is provided to further support the porous concrete section. A bore extending from the porous concrete down to the aquifer is also provided, and is filled with rocks.
An aquifer replenishing concrete gutter formation method is provided, comprising the steps of: (a) forming a gutter section between an elevated curb section and a road surface; (b) boring a hole in the gutter section into the aquifer; (c) filling the hole with rocks; (d) filling the gutter section with porous concrete; and (e) curing the porous concrete. In accordance with another aspect of the present invention, step (a) includes removing a section of the road surface adjacent to the elevated curb section. Finally, step (a) also includes forming a cut off wall extending downwards from the road surface and offset from the elevated curb section.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other features and advantages of the various embodiments disclosed herein will be better understood with respect to the following description and drawings, in which like numbers refer to like parts throughout, and in which:
FIG. 1 is a cross-sectional view of the surface of the earth;
FIG. 2 is a perspective cross-sectional view of a road surface aquifer replenishment system in accordance with an aspect of the present invention;
FIG. 3 is a cross-sectional view of a gutter aquifer replenishment system in accordance with an aspect of the present invention;
FIG. 4 is a cross-sectional view of a conventional road;
FIG. 5 is a cross-sectional view of a conventional road excavated for retrofitting an aquifer replenishment system in accordance with an aspect of the present invention;
FIG. 6 is a cross-sectional view of conventional road after excavation and formation of a cut-off wall in accordance with an aspect of the present invention; and
FIG. 7 is a cross sectional view of a road after excavating a bore reaching an aquifer and filling the same with rocks, and depicts the pouring of concrete into the gutter section in accordance with an aspect of the present invention.
DETAILED DESCRIPTION
The detailed description set forth below in connection with the appended drawings is intended as a description of the presently preferred embodiment of the invention, and is not intended to represent the only form in which the present invention may be constructed or utilized. It is to be understood, however, that the same or equivalent functions may be accomplished by different embodiments that are also intended to be encompassed within the spirit and scope of the invention.
With reference now to FIG. 1 , a cross sectional view of the earth's surface is shown. Atmosphere 30 is shown with clouds 32 releasing precipitation 34 , falling towards the ground 50 . As is well understood, ground 50 is comprised of top soil layer 52 . Underneath top soil layer 52 is clay layer 54 , and underneath that is sand lens 56 . Aquifer 60 is a layer of water, and can exist in permeable rock, permeable mixtures of gravel, and/or sand, or fractured rock 58 . Precipitation 34 falls on top soil layer 52 , and is gradually filtered of impurities by the varying layers of sand, soil, rocks, gravel, and clay as it moves through the same by gravitational force, eventually reaching aquifer 60 . In the context of the above natural features, the present invention will be described.
Referring now to FIG. 2 , a first embodiment of the present inventive concrete paving system 100 is shown. Situated above clay layer 54 is an aggregate leach field 82 comprised of sand and gravel particles. Above aggregate leach field 82 is a pavement layer 80 , which by way of example only and not of limitation, is concrete composed of Portland cement and an aggregate. Pavement layer 80 may be reinforced with any reinforcement structures known in the art such as rebar, rods and so forth for increased strength. Preferably, the reinforcement structure has the same coefficient of thermal expansion as the pavement material, for example, steel, where concrete is utilized, to prevent internal stresses in increased temperature environments. By way of example only and not of limitation, pavement layer 80 has reinforcement bars 90 . It will be appreciated by one of ordinary skill in the art that the pavement layer 80 need not be limited to architectural concrete, and asphalt and other pavement materials may be readily substituted without departing from the scope of the present invention.
Extending from the top surface to the bottom surface of pavement layer 80 are one or more surface drains 84 . Due to the fact that non-porous concrete, that is, concrete having aggregate mixed into the cement, permits little water to seep through, surface drains 84 expedite the water flow into aggregate leach field 82 . Typically, by way of example only and not of limitation, surface drains 84 are filled with rocks to prevent large debris such as leaves and trash from clogging the same.
Within aggregate leach field 82 are one or more leach lines 86 , which assist the transfer of fluids arriving through surface drains 84 . By way of example only, leach lines 86 are in direct fluid communication with surface drains 84 . Leach lines 86 have a higher porosity than the surrounding leach field 82 to enable faster transmission of fluids. Leach field 82 is also capable of absorbing water, and in fact, certain amounts are absorbed from leach lines 86 . Additional water flowing from surface drains 84 is also absorbed into leach field 82 . In this fashion, water is distributed across the entire surface area of leach field 82 , resulting in greater replenishment of the aquifer. A person of ordinary skill in the art will recognize that the leach field 82 acts as a filter by gradually removing particulates from precipitation, and resulting in cleaner water in the aquifer.
As is well understood in the art, clay has a lower porosity as compared to an aggregate of, for example, sand, gravel, or soil. In order to expedite the transmission of water into the aquifer, aggregate drains 88 extend from aggregate leach field 82 , through clay layer 54 , and into sand lens 56 . Therefore, a minimal amount of water is absorbed into the clay layer 54 , and the replenishment process is expedited.
After the water flows from leach field 82 into sand lens 56 via aggregate drains 88 , it is dispersed throughout sand lens 56 , trickling through to the aquifers in the vicinity. The water in the aquifer is thus replenished through largely natural means, namely the filtration process involved in absorbing precipitation through aggregate leach field 82 and sand lens 56 , despite the existence of a non-porous material such as concrete overlying the ground surface in the form of pavement layer 80 .
The aquifer replenishment system as described above is generally formed over previously undeveloped land, or any land that has been excavated to a clay layer 54 . Thus, surfaces that have been previously paved by other means must first be removed so that the natural water absorption mechanisms of the earth are exposed. After this has been completed, aggregate drains 88 are drilled from the exposed clay surface 54 into sand lens 56 . After filling the aggregate drains 88 with aggregate, a generally planar aggregate leach field 82 is formed. Contemporaneously, leach lines 86 are formed, and is encapsulated by the aggregate which constitutes leach field 82 . After leach field 82 is constructed, concrete reinforcements 90 are placed, and uncured concrete is poured to create pavement layer 80 .
With respect to the formation of surface drains 84 , any conventionally known methods of creating generally cylindrical openings in concrete may be employed. For example, before pouring the uncured concrete, hollow cylinders may be placed and inserted slightly into leach field 82 to prevent the concrete from flowing into the opening. Yet another example is pouring the concrete and forming a continuous layer, and drilling the concrete after curing to form surface drain 84 . It is to be understood that any method of forming surface drain 84 is contemplated as within the scope of the present invention.
With reference to FIG. 3 , a second embodiment of the aquifer replenishing system 200 is shown, including an elevated curb section 192 , a gutter section 196 , and a road pavement section 190 . Road pavement section 190 is comprised of a pavement surface 195 , which by way of example only and not of limitation, is architectural concrete, asphalt concrete, or any other paving material known in the art, and is supported by base course 194 . Base course 194 is generally comprised of larger grade aggregate, which is spread and compacted to provide a stable base. The aggregate used is typically ¾ inches in size, but can vary between ¾ inches and dust-size.
In accordance with the present invention, gutter section 196 has a porous concrete gutter 184 in which the top surface thereof is in a substantially co-planar relationship with the top surface of pavement surface 195 . Optionally, porous concrete gutter 184 is supported by base 185 which is composed of similar aggregate material as base course 194 . Furthermore, extending from optional base 185 into aquifer 60 is a rock filled bore 188 . As a person of ordinary skill in the art will recognize, a bore filled with rocks will improve the channeling of water due to its increased porosity as compared with ordinary soil. Optional base 185 and porous concrete gutter 184 is laterally reinforced by cut off walls 183 and elevated curb section 192 . The cut off walls 183 are disposed on opposing sides of the porous concrete gutter 184 and the base 185 between the elevated curve section 192 and the pavement surface 195 . It is expressly contemplated that the cut off walls 183 may be pre-cast or cast in place.
When precipitation falls upon road pavement section 190 , the water is channeled toward gutter section 196 . Porous concrete gutter 184 permits the precipitation to trickle down to aquifer 60 . When optional base 185 and rock filled bore 188 is in place, there is an additional filter effect supplementing that of the porous concrete gutter 184 . A similar result can be materialized where the water drains from the upper surface of elevated curb section 192 , or precipitation directly falls upon porous concrete gutter 184 . Please note a large surface drain may be used in lieu of the porous concrete gutter.
This embodiment is particularly beneficial where retrofitting the gutter is a more desirable solution rather than re-paving the entire road surface. In a conventional road pavement as shown in FIG. 4 , pavement surface 195 and base course 194 extend to abut elevated curb section 192 . In preparation for retrofitting gutter section 196 , a section of pavement surface 195 and base course 194 is excavated as shown in FIG. 5 , leaving a hole 197 defined by the exposed surfaces of elevated curb section 192 , base course 194 , and pavement surface 195 . This is followed by the optional step of pouring and curing a cut-off wall 183 as illustrated in FIG. 6 , which, as discussed above, serves to reinforce the gutter section 196 . One or more bores 188 are drilled down to aquifer 60 , and filled with rocks, as shown in FIG. 7 . An optional base of aggregate 185 is formed above rock filled bore 188 , and compacted by any one of well recognized techniques in the art. Finally, a volume of porous concrete mixture, that is, a concrete without sand or other aggregate material, is poured and cured, forming porous concrete gutter 184 . While recognizing the disadvantages of using porous concrete, namely, the reduced strength of the resultant structure, a person of ordinary skill in the art will also recognize that gutter section 196 sustains less stress thereupon in normal use as compared to road pavement section 190 .
The above description is given by way of example, and not limitation. Given the above disclosure, one skilled in the art could devise variations that are within the scope and spirit of the invention disclosed herein. Further, the various features of the embodiments disclosed herein can be used alone, or in varying combinations with each other and are not intended to be limited to the specific combination described herein. Thus, the scope of the claims is not to be limited by the illustrated embodiments. | A concrete structure for replenishing an aquifer and a method for constructing the same is provided. The structure is comprised of a pavement layer with surface drains that extend through the pavement layer and into an aggregate leach field. The leach field includes leach lines spanning the leach field. An aggregate drain extends from the leach field into a sand lens. Precipitation which falls upon the structure thus flows through the surface drain, absorbed into the aggregate leach field, and transported to the aggregate drains by way of aggregate leach lines. The water is then absorbed into the sand lens, ultimately replenishing the aquifer. Existing conventional pavement structures are retrofitted by the removal of a section of the pavement, and filling the same with porous concrete. | 4 |
RELATED APPLICATION
This application is a continuation-in-part of Ser. No. 08/310,473, filed Sep. 22, 1994, now abandoned.
BACKGROUND OF INVENTION
The present invention relates generally to a central processor unit ("CPU") that supports an integer-multiply instruction and determines an overflow trap without reference to the high order bits of the intermediate result.
Microprocessors typically include arithmetic logic units ("ALU") for performing common arithmetic functions. These functions are available to the programmer through a software instruction. One such function is "integer-multiply."
A typical integer-multiply instruction causes two n-bit operands to be multiplied, thereby producing a 2n-bit intermediate result, where n commonly equals 8, 16, or 32. The low order bits of the intermediate result are returned as the multiplication result, while the high order bits are used for calculating the overflow trap of the instruction, which is signaled if the result of the multiplication is too big to be represented using an n-bit number.
CPU's which support integer-multiply instructions are well known. For example, National Semiconductor's 32000 series of microprocessors provide the MULi instruction, which causes the CPU to signal an overflow trap when the result of the MULi operation cannot be represented using an n-bit result. As shown in FIG. 1, the MULi instruction calculates the overflow trap by multiplying n-bit operand A (stored in register 10) together with n-bit operand B (stored in register 12) in multiply unit 14. A 2n-bit intermediate result C is produced by the multiplication and stored in register 16. The low order n bits of the intermediate result register 16 are the multiplication result D and are stored in register 18. The high order n+1 bits of the intermediate result register 16 are then examined by overflow logic unit 20 to determine whether an overflow occurred according to one of two known methods.
First, if the sign-bit of the result register 18 is 0 (indicating a positive signed result), then the n high order bits of the intermediate result register 16 are logically combined in an OR gate (not shown). If the sign-bit of the result register 18 is 1 (indicating a negative result), then the n high order bits of the intermediate result register 16 are logically combined together in an AND gate (not shown). If the result of the selected operation above is 1, i.e., at least one of the high order bits is not equal to the sign bit, then an overflow condition is signaled.
Second, the n high order bits of the intermediate result register 16 are added with the value 0 using an arithmetic logic unit ("ALU") of the CPU. The sign bit is used as a carry-in bit for the ALU. If the result of the ALU operation is not 0, i.e., at least one of the high order bits is not equal to the sign-bit, which is indicated by a zero-flag of the ALU, then an overflow is signaled.
It would be desirable if the overflow trap of the integer-multiply instruction could be performed without reference to the high order n-bits of the intermediate result, and the present invention provides a method for doing so.
SUMMARY OF THE INVENTION
The present invention signals an overflow trap for an integer-multiply instruction without reference to the high order n bits of the intermediate result. Instead, the multiply unit multiplies 2n-bit operands and produces a n+1 bit result. The low order n-bits are returned as the multiplication result. A first overflow logic unit examines the leading bits of both operands and counts the number of leading bits which are equal to the respective sign bits. If the count is smaller than n, an overflow trap is signalled.
If not, then a second logic unit examines bits n and n-1 of the intermediate result and signals an overflow trap if these bits are not equal.
A better understanding of the features and advantages of the present invention will be obtained by reference to the following detailed description of the invention and accompanying drawings which set forth an illustrative embodiment in which the principles of the invention are utilized.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates the basic block diagram for conventional overflow calculation logic for the MULi instruction.
FIG. 2 illustrates the basic block diagram for overflow calculation logic for the MULi instruction according to the present invention.
FIG. 3 is a flow chart illustrating the method for overflow calculation according to the present invention.
FIG. 4 illustrates a specific embodiment of the overflow logic blocks shown in FIG. 2.
DETAILED DESCRIPTION OF THE INVENTION
The present invention provides a method and apparatus for calculating the overflow for an integer-multiply instruction performed in a CPU. Implementation of the method requires little additional hardware and does not reduce the performance of the CPU. The CPU should be capable of manipulating integer data operands of 8, 16, and 32 bits, and floating-point operands of 32 and 64 bits. Many such CPU's are known, such as National Semiconductor's 32000 series of microprocessors. The CPU must support various arithmetic and logic operations, including multiply operations. CPU's typically support two types of multiply operations, namely a floating-point multiply operation and an integer-multiply operation. National's 32000 series of microprocessors implement these operations with the mnemonic instructions MULf and MULi, respectively.
Referring now to FIG. 2, the CPU (not shown) includes an arithmetic logic unit (ALU) 114 which performs both types of multiply operations. The ALU 114 is typically capable of very high performance, e.g., 50 MHz clock cycles, such that a MULf instruction can be initiated once every two clock cycles, and a MULi instruction can be initiated once every clock cycle if overflow signaling is disabled and once every two clock cycles if overflow signaling is enabled.
According to the present invention, the CPU responds to the MULi instruction by latching the two n-bit operands A and B, stored in n-bit registers 110 and 112, respectively, into the ALU 114 and then multiplying the operands together to produce an n+1 bit result C which is stored in register 116.
In parallel with the multiply operation of ALU 114, a first overflow logic unit 120 counts the total number of "leading sign bits" in registers 111 and 121. The phrase "leading sign bits" is defined to include the sign bit and successive bits of each operand which are equal to the sign bit. For example, if Operand A is the 4 bit signed value -4 (1100), then the number of leading sign bits associated with Operand A is two. If Operand B is the 4 bit signed value -3 (1011), then the number of leading sign bits associated with Operand B is one. Therefore, the total number of leading sign bits for these operands is three, meaning that in accord with the present invention, an overflow will be indicated.
Overflow will occur where the total count of leading sign bits is less than n. Otherwise, more information is required to determine whether an overflow will occur or not, as follows.
If the overflow logic unit 120 has determined that an overflow will occur during the first cycle, then an overflow trap is signaled. If the overflow logic unit 120 could not determine whether an overflow would occur during the first cycle, then, during a second CPU cycle, bits n and n-1 of the intermediate result register 116 are examined by a second overflow logic unit 122. If bits n and n-1 of the intermediate result register 116 are not equal, then an overflow trap is signaled. If not, then the multiplication result can be represented using a n-bit signed number and the overflow trap need not be signaled.
A simple flow chart of the present method is illustrated in FIG. 3. In step 200, the total count of "leading sign bits" is determined. In step 202, the count is compared to n, which is the number of bits in each operand. If the count of leading sign bits is less than n, then an overflow is indicated in step 204. If not, then bits n and n-1 of the multiplication result are compared to each other in step 206. If bits n and n-1 are not equal, then an overflow is indicated in step 208.
According to the present method, a CPU can implement an integer-multiply instruction supporting overflow trap signaling with a minimum of additional hardware and without impacting the performance.
For example, a 4 bit implementation for the first overflow logic unit 120 and the second overflow logic unit 122 is shown in FIG. 4. It should of course be recognized that the example could be extended to any number of bits.
A 4 bit value a 3 a 2 a 1 a 0 is loaded into register 310, wherein bit a 3 is the most significant bit and the sign bit. A 4 bit value b 3 b 2 b 1 b 0 is loaded into register 312, wherein bit b 3 is the most significant bit and the sign bit. In the preferred embodiment described herein, the value a 3 a 2 a 1 a 0 in register 310 is the two's complement value of Operand A, and the value b 3 b 2 b 1 b 0 in register 312 is the two's complement value of Operand B.
The first overflow logic unit 120 includes an XOR gate for each bit (other than the MSB) to compare each bit to the MSB. Each of the XOR gates 150, 152 and 154 has one of its inputs coupled to the most significant bit a 3 of register 310. XOR gate 150 has its second input coupled to the next successive bit a 2 . XOR gate 152 has its second input coupled to the next successive bit a 1 . XOR gate 154 has its second input coupled to the next successive (least significant) bit a 0 (although this gate is unnecessary to implement the invention). Likewise, each of XOR gates 156, 158 and 159 has one of its inputs coupled to the most significant bit b 3 of register 112. XOR gate 156 has its second input coupled to the next successive bit b 2 . XOR gate 158 has its second input coupled to the next successive bit b 1 . XOR gate 159 has its second input coupled to the next successive (least significant) bit b 0 (although this gate is unnecessary to implement the invention).
The outputs 160, 162, 164, 166, 168, 169 of XOR gates 150, 152, 154, 156, 158 and 159, respectively, are coupled to AND gates 170, 172 and 174, as follows. Outputs 160 and 162 are coupled to the input of AND gate 172. Outputs 160 and 166 are coupled to the input of AND gate 174. Outputs 166 and 168 are coupled to the input of AND gate 170.
The outputs 180, 182 and 184 from AND gates 170, 172 and 174, respectively, are coupled to inputs of a NOR gate 186. The output 188 of NOR gate 186 is coupled to one input of an OR gate 190.
The other input to OR gate 190 is from an XOR gate 192, which has two inputs coupled to bits n and n-1 of the intermediate result register 116.
The output 188 of NOR gate 186 is the output of the first overflow logic unit 120 and will be true if the total number of "leading sign bits" is less than four, indicating that an overflow condition exists. In that event, the output 194 of OR gate 190 will also be true.
If the total number of "leading sign bits" is greater than or equal to four, then output 188 will be false. In that event, an overflow will only be indicated if bit n and bit n-1 are not the same.
It should be understood that the invention is not intended to be limited by the specifics of the above-described embodiment, but rather defined by the accompanying claims. | An arithmetic logic unit includes overflow trap logic for an integer-multiply instruction. A multiply unit multiplies a pair of n-bit operands together and produces a n+1 bit result. The low order n-bits are returned as the multiplication result. A first overflow logic unit examines the leading bits of both operands and counts the number of leading bits which are equal to respective sign bits. If the count is smaller than n, an overflow trap is signalled. If not, then a second logic unit examines bits n and n-1 of the result and signals an overflow trap if these bits are not equal. | 6 |
FIELD OF THE INVENTION
This invention relates generally to the field of thermoplastic multicomponent fibers and processes for making them. More particularly, this invention relates to multicomponent fibers having additives in one or more of the components and processes for making such fibers.
BACKGROUND OF THE INVENTION
As used in this specification, the following terms have the meanings ascribed to them below. "Fiber" or "fibers" means the basic element of fabric or other textile structures which is characterized by a length at least 100 times its diameter or width and made from a synthetic polymer matrix. The term "fiber" encompasses short length fibers (i.e., staple fibers) and fibers of indefinite length (i.e., continuous filaments).
"Multicomponent fiber" or "Multicomponent fibers" means fibers having at least two longitudinally co-extensive domains or components. These domains (or components) may differ in the identity of the polymer matrix, or in the type or amount of additives present in each domain, or in both the identity of the matrix and the additive level or identity.
"Bicomponent fiber" or "bicomponent fibers" means a multicomponent fiber having only two different longitudinally coextensive domains.
"Sheath/core fiber" or "sheath/core fibers" means multicomponent fibers having one or more outer domains that substantially surround at least one or more inward domain. An outer domain that substantially surrounds an inward domain abuts more than 50% of the inner domain's periphery.
"Nonaqueous liquid" means a material which is substantially flee from water and is in the liquid state at conditions commonly found in buildings and other environments occupied by humans typically 50°-110° F.
Multicomponent fibers are known. Multicomponent fibers may be classified into one of at least three major classes. One class includes multicomponent fibers with the components differing from each other in the type of polymer matrix forming each component. Such fibers are described in, for example, U.S. Pat. No. 4,285,748 to Booker et at.
Another class of multicomponent fibers includes those with components differing in the level or type of additive in the components but where the matrix polymers are predominately the same or similar. An example of this type of multicomponent fiber is described in U.S. Pat. No. 5,019,445 to Sternlieb.
A further category of multicomponent fibers includes fibers with components differing in both the polymeric matrix material and the relative amount of additives or types of additives in each component. Examples of such multicomponent fibers are described in U.S. Pat. No. 3,803,453 to Hull; U.S. Pat. No. 4,185,137 to Kinkel; and U.S. Pat. No. 5,318,845 to Tanaka.
In certain circumstances during the manufacture of multicomponent fibers, significant concern is given to whether or not such fibers will separate at the interface between components. One reason multicomponent fibers separate is due to the incompatibility of the components. Sometimes, it is desirable that the components separate at the interface between them. For example, the incompatibility principle can be used to make microfibers by fibrillating multicomponent fibers along the component interface thereby resulting in fibers of decreased size. To make such microfibers, therefore, the incompatibility of the components might be intentionally maximized.
In other circumstances, however, it is undesirable for the components to separate from each other. For these cases, care must be taken in selecting matrix polymers and additives to assure sufficient compatibility or, rather, to prevent so much incompatibility that the fibers delaminate when subjected to post-spinning stress, e.g., bending around a godet.
Methods for adding additives to fibers are known. For example, U.S. Pat. No. 5,308,395 to Burditt describes a liquid carrier for incorporation into polymeric resins. This patent describes the use of such carriers to make fibers but does not address multicomponent fibers.
Also, U.S. Pat. No. 5,364,582 to Lilly describes the use of a certain carrier to add polyoxyethylene alkylamine antistatic agents to monocomponent fibers. The carriers may be an organic resin based composition containing surfactant and diluent.
Moreover, the ability to add additives directly to a fiber extrusion line without the necessity of storing and metering extremely dry additive-containing chip provides significant process and economic advantages. U.S. Pat. No. 5,236,645 to Jones describes an aqueous based system for adding additives directly to a fiber extrusion process. The aqueous portion is removed through a vent in the extruder so that water is not significantly present in the extruder output. However, the addition of aqueous mixes to polymer melts may sometimes significantly reduce the relative or intrinsic viscosity of the polymer. This is true, for example, with nylon 6 and, to a larger extent, with polyester. The loss in viscosity has a significant effect on yam physical properties and the ability to successfully spin fibers.
Therefore, there remains a need for methods to add additives inline during the fiber extrusion process without requiring removal of water and without leading to incompatibility problems resulting in delamination at the interface between components.
SUMMARY OF THE INVENTION
Accordingly, one embodiment of the present invention is a process for producing multicomponent fibers. The process comprises providing a dispersion of a particulate additive or chemical compound in a nonaqueous liquid carrier; forming a blend of a first thermoplastic polymer and the dispersion by injecting the dispersion into an extruder which is part of a fiber extrusion apparatus and which extruder is extruding the first thermoplastic polymer thereby forming a blend of the additive in the first thermoplastic polymer; providing a second thermoplastic polymer to the fiber extrusion apparatus; in the fiber extrusion apparatus, arranging the blend and the second thermoplastic polymer in a preselected, mutually separated relative arrangement; directing the arrangement of the blend and the second thermoplastic polymer to a spinneret which is a part of the fiber extrusion apparatus while maintaining the preselected, mutually separated relative arrangement; extruding the directed arrangement of the blend and the second molten polymer through the spinneret to form multicomponent fibers; and solidifying the multicomponent fibers.
Another embodiment of the present invention is a multicomponent fiber comprising a first longitudinally extensive domain formed from a blend of a first thermoplastic polymer with a particulate additive dispersed in a nonaqueous carrier; and a second longitudinally extensive domain of a second thermoplastic polymer arranged coextensively with the first longitudinally extensive domain and a forming an outer domain that substantially surrounds the first longitudinally extensive domain.
It is an object of the present invention to provide a process for adding additives in nonaqueous carriers directly to a multicomponent fiber extrusion line without causing incompatibility associated problems between the components of the fiber.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
To promote an understanding of the principles of the present invention, descriptions of specific embodiments of the invention follow and specific language describes the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, and that such alterations and further modifications, and such further applications of the principles of the invention as discussed are contemplated as would normally occur to one ordinarily skilled in the art to which the invention pertains.
One embodiment of the present invention concerns a process for producing multicomponent fibers. In this process, a dispersion of a particulate additive in a nonaqueous liquid carrier is provided. This dispersion is injected into an extruder. The extruder is part of an entire fiber extrusion system, i.e., apparatus. The extruder is extruding a first thermoplastic polymer and, after injection of the dispersion into the extruder, a blend of the first thermoplastic polymer with dispersion is formed.
A second thermoplastic polymer is also provided to the fiber extrusion apparatus and, in the apparatus, arranged with the blend in a preselected, mutually separated relative arrangement. This arrangement is directed to a spinneret (also part of the fiber extrusion apparatus) and extruded into multicomponent fibers which are then solidified. The fiber so formed may be subsequently processed according to conventional downstream processes depending on the intended use (e.g., carpet fiber processes for carpet fibers). Surprisingly, the presence of the nonaqueous liquid carrier does not cause incompatibility problems during such subsequent processing of the multicomponent fiber and even in the ultimate end use.
Preferred additives for incorporation into multicomponent fibers according to the present invention include a variety of particulate additives such as pigments, TiO 2 light stabilizers, heat stabilizers, flame retardants, antistatic compounds, antibacterial compounds, antistain compounds, pharmaceuticals and carbon black.
The nonaqueous liquid carrier can be any nonaqueous liquid carrier that is compatible with the polymers being extruded. Preferred carriers are based upon or derived from gum, wood and/or tall oil resin which are mainly of the fused-ring monocarboxylic acids. These preferred nonaqueous liquid carriers are described in U.S. Pat. No. 5,308,395 to Burditt et al., the specification of which is hereby incorporated by reference.
The thermoplastic polymer which is blended with the additive/carrier system may be any one of a wide variety of fiber-forming polymeric materials. For example, this thermoplastic polymer may be selected from the polyamides, polyesters, polyacrylics, polyethers, polycaprolactones and polyolefins.
The second thermoplastic polymer may also be selected from the wide variety of fiber-forming polymers. These polymers include polyamides, polyesters, polyacrylics, polyethers, polycaprolactones and polyolefins.
The particulate additive may be dispersed in the nonaqueous liquid carrier by known mixing techniques. Exemplary techniques for mixing are described in Burditt, incorporated by reference above. The concentration of additives in the dispersion will depend on the particular additive, the spinning conditions and the desired concentration of additive in the fiber end product. For example, in the case of carbon black, additive mixtures containing up to about 40 wt % of carbon black in an organic resin-based carrier have been used. Higher and lower loadings are envisioned.
The injection of the dispersion may be accomplished according to known techniques. To illustrate, conventional fiber spinning equipment may be equipped with an injection port that can be in one or more areas: 1) injection port (for a robe or nozzle-typically made of stainless steel) at the extruder feed throat can be thorugh the throat housing, or the tube may be extended through the polymer chip feed port to a point just above the extruder screw flight or flights; 2) an injection port area along the extruder barrel that allows for injection prior to a mixing area; or 3) an injection port area along the polymer distribution line prior to a mixing device such as an inline static mixer commonly used in the trade.
The injection port is equipped with a tube or nozzle that is plumbed to the outlet of a pump that has a very highly accurate rate of delivery. The pumps can be gear, piston, etc., as supplied by a host of vendors such as, Bannag, Zenith, and Feinpruef. They are linked mechanically or preferably electronically to the extruder such that the injection pump output automatically follows the polymer throughput to keep the addition rate constant. The injection pump feed is connected to a vessel that is a reservoir for the additive.
The fibers may be spun according to conventional multicomponent spinning equipment with appropriate considerations for the differing properties of the two components. One such exemplary spinning method is described in U.S. Pat. No. 5,162,074 to Hills. The patent is incorporated by reference for the spinning techniques described therein.
The fibers of the present invention can be made in a wide variety of deniers per filament (dpf). It is not currently believed that there are any limitations on denier and the desked denier depends upon the end use.
Another embodiment of the present invention is a multicomponent fiber having a first longitudinally extensive domain formed from a blend of a first thermoplastic with a particulate additive dispersed in a nonaqueous carrier and a second longitudinally extensive domain of a second thermoplastic polymer arranged coextensively with the first longitudinally extensive domain. Especially preferred arrangements of the domains are such that the second polymer forms an outer domain that substantially surrounds the first longitudinally extensive domain.
These fibers produced by the present invention may be round or nonround, eccentric or concentric sheath/core configurations, side-by-side, islands-in-the sea or any other multicomponent fiber configuration and combinations of these. Multicomponent fibers of this embodiment may be made with the materials and processes described above.
This invention will now be described by reference to the following detailed examples. The examples are set forth by way of illustration, and are not intended to limit the scope of the invention. In the following examples, the listed factors are measured as follows:
Change in pressure:
Measurement of polymer pressure in the polymer distribution system can be monitored at any given moment, or the pressure can be recorded over a period of time to calculate the amount of change. The pressure is measured using pressure transducers in contact with the molten polymer and the resulting signal converted to a digital readout using a distributive control system (DCS) such as systems available from Foxboro Company.
Polymer Throughput:
Polymer throughput is the weight (in grams) of polymer pumped through the spinneret (or one hole of the spinneret depending on which value is desired) for a given period of time (usually in one minute). The throughput is measured by weighing the polymer extruded for a given time and calculating the weight in grams per minute.
Filtration factor:
(also referred to as a Pressure Rise Index Test)
This factor is the pressure rise per gram of additive measures pressure rise based on the grams of additive (pigment only) being pumped through the spin pack consisting of a filtration medium and spinneret. In the following examples the filtration medium is a series of plates stacked from top to bottom (relative to polymeric flow) as follows:
35 mm screen (165×1420)
35 mm breaker plate 10 mm thick
12 hole spinneret (250 μ holes)
Pressure is set at 2000 psi initially and pressure measurements are made at intervals.
______________________________________Polyester intrinsic Goodyear Tire and Rubber Companyvisosity: Method R100Dry heat shrinkage ASTM D2259-87Boiling water shrinkage ASTM D2259-87 (modified to eliminate surfactants in boiling water)______________________________________
The following examples are set forth as illustrative of the present invention, to enable one skilled in the art to practice the invention. These examples are not to be read as limiting the invention as defined by the claims set forth herein.
EXAMPLE 1
(The Invention)
A liquid dispersion containing 40% by weight of carbon black is prepared by adding 40 grams of carbon black to 60 grams of a vehicle as described in U.S. Pat. No. 5,308,395. This dispersion is evaluated and produces the following results:
______________________________________Change in Pressure (psi) 890Polymer Throughput (g/min) 32.08Evaluation time (min) 240Filtration Factor 38______________________________________
A fiber melt spinning system is spinning sheath/core bicomponent fibers from poly(ethylene terephthalate) ("PET") (0.640 IV measured in 60/40 phenol/1,1,2,2, tetrachloroethane) and polycaprolactam (nylon 6) (2.80 RV measured in 90% formic add). The poly(ethylene terephthalate) forms the core and the nylon 6 forms the sheath. The core makes up 77 wt % of the fiber. The liquid dispersion of carbon black is added at the extruder throat via an injection gear pump. The addition rate is adjusted to provide 0.03% weight of carbon black in the PET core polymer. No fluctuations are noted in extruder screw speed, or pressure.
The bicomponent fiber is wound up at 3500 m/min using conventional equipment. The physical properties of this yam are measured and reported in Table 1.
The yarn is melt bonded to give a nonwoven having a weight of 175 gms/m 2 and several properties are evaluated. Table II shows these properties.
EXAMPLE 2
(Comparative Example)
(Yarn from Concentrate Chip)
Polymer chips containing about 0.6% carbon black in PET are metered to the polymer chip stream such that the extruded polymer contains 0.03 % carbon black. The crystallized chips (with and without carbon black) have an intrinsic viscosity of 0.640.
A fiber melt spinning system is spinning sheath/core bicomponent fibers from the PET with 0.03% carbon black and nylon 6. The PET forms the core and the nylon 6 forms the sheath. This bicomponent fiber is wound up into a 110 filament yarn. The physical properties of this yarn are measured and reported in Table I.
The yarn is melt bonded to give a nonwoven fabric having a weight of 175 gms/m 2 and several properties are evaluated. Table II shows these nonwoven properties.
TABLE I______________________________________ Example 1 Example 2Yarn Property (invention) (comparative)______________________________________Intrinsic Viscosity 0.584 0.604DL after Crocking 1.98 1.66DTEX 1651 1654Load at 10% Elongation (N) 27.0 27.8Load at 20% Elongation (N) 35.4 36.8Load at 45% Elongation (N) 49.2 57.7Load at Break (N) 51.6 58.2Elongation at 20N 4.1 3.9Elongation at Break (%) 49.8 60.2Boiling Water Shrinkage (%) 3.9 2.8Dry Heat Shrinkage (%) 9.1 7.9Density 1.327 1.328DSC Melt (°C.) 220/250 220/250Cool (°C.) 175/195 175/197Remelt (°C.) 211/253 209/253TGA % Weight Loss 28-320° C. 1.24 1.80TGA % Weight Loss (ISO) at 0.41 0.39210° C. 15 min______________________________________
Table I shows the yarn properties of each bicomponent yarn. Thermogravimetric analysis did not indicate that the nonaqueous liquid carrier off gassed at spinning temperatures. Lack of off-gassing supports that the carrier does not cause or tend to cause delamination of the components. Thermogravimetric analysis shows no significant differences in volatiles between the comparative yarn and yarn made according to the invention.
TABLE II______________________________________ Example 1 Example 2Nonwoven Fabric Property (invention) (comparative)______________________________________TGA % Weight Loss 28-315° C. 0.8 0.9DSC Melt Peak (°C.) 217/250 217/254DSC Remelt Peak (°C.) 217/252 217/252TGA % Weight Loss (ISO) @ 0.3 0.3215° C. 15 minTrapezoid Tear MD (N) 338 364Trapezoid Tear XMD (N) 311 313Load at Break MD 13544 13701(2 x 8 inch) N/MLoad at Break XMD (N/M) 11300 11733Elongation at Break MD (%) 32 34Elongation at Break XMD (%) 30 34Mass (G/M.sup.2) 180 178Puncture (N) 339 341Nonwoven Fabric Shrinkage 1.083 1.273MD (%)Nonwoven Fabric Shrinkage 1.187 1.205XMD (%)______________________________________ | A process for producing multicomponent fibers provides a dispersion of a particulate additive or chemical compound in a nonaqueous liquid carrier; forms a blend of a first thermoplastic polymer and the dispersion by injecting the dispersion into an extruder which is part of a fiber extrusion apparatus and which extruder is extruding the first thermoplastic polymer thereby forming a blend of the additive in the first thermoplastic polymer; provides a second thermoplastic polymer to the fiber extrusion apparatus; in the fiber extrusion apparatus, arranges the blend and the second thermoplastic polymer in a preselected, mutually separated relative arrangement; directs the arrangement of blend and the second thermoplastic polymer to a spinneret which is a part of the fiber extrusion apparatus while maintaining the preselected, mutually separated relative arrangement; extrudes the directed arrangement of the blend and the second molten polymer through the spinneret to form multicomponent fibers; and solidifies the multicomponent fibers. | 3 |
BACKGROUND OF THE INVENTION
The present invention relates to bass reflex speaker systems with ducted ports. Such speaker systems are well known in the art of loudspeaker design, and have been sold and used in the USA since 1938. A bass reflex system provides improved efficiency and lower frequency limit than a speaker with a closed cabinet. This is because it acts as a Helmholtz resonator, which supplies low frequency sound waves from the rear of the driver to the outside of the cabinet in phase with the direct sound waves from the front of the driver. The desired resonance frequency is determined by the air mass in the ducted port and the compliance of the air volume in the cabinet.
The duct alone, however, also can act as a resonator for sound waves with half-wave length equal to the length of the duct or a fraction thereof. This is an undesirable effect, because frequencies corresponding to such resonances will pass from the inside of the cabinet to the outside, and will color the midrange sound of the speaker. The audible effect of such undesirable resonances can be reduced or eliminated by forcing the sound across different parts of the cross section of the duct to travel different distances, or by adding a low-pass filter after the duct.
The first type of solution can be approximated by using a duct that is sharply bent. Another example of this type of solution is described in U.S. Pat. No. 4,933,982, which uses a straight duct containing coaxial inserts to force the sound waves to travel different distances between the input and exit openings. Both types of duct are, however, expensive to make, and the latter is quite bulky.
An example of the second type of solution is described in U.S. Pat. No. 4,953,655, where a bass reflex duct terminates in a separate chamber with a port to the outside of the cabinet. The separate chamber with its port acts as a low pass filter, which removes resonances in the duct before the sound from the duct is allowed to reach the outside of the speaker cabinet. The size, the complexity, and the cost of the speaker cabinet, however, are increased by the extra chamber.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a bass reflex type speaker system which uses a ducted port, but does not suffer from undesirable leakage of mid-frequency signals from the interior of the speaker cabinet through the ducted port, and does not require complicated, bulky, or expensive designs of the duct or the speaker cabinet.
Additional objects and advantages of the invention will be set forth in part in the description which follows, and, in part, will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out in the appended claims.
The objects of this invention are achieved by a bass reflex type speaker system comprising a cabinet, a driver mounted in the cabinet for transmitting sound waves inside the cabinet, a bass reflex port in a wall of the cabinet, a duct open at both ends mounted inside the cabinet with one end connected to the port, the duct having at least one additional opening between its ends, and a deflectable membrance covering the additional opening.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.
FIG. 1 is a vertical section through a first embodiment of a bass reflex speaker system according to the invention.
FIG. 2 is a view of the duct used in the speaker system of FIG. 1, as seen from the left side.
FIG. 3 is a graph showing sound pressure at the bass reflex port of the speaker system of FIG. 1 as a function of frequency for a duct with solid wall (solid line), and for a duct according to the invention (dotted line).
FIG. 4 is a vertical section through an inelastic membrance mounted on a duct of a second embodiment of a bass reflex speaker system according to the invention.
FIG. 5 is a front view of the membrance shown in FIG. 4 mounted on a duct.
FIG. 6 is a horizontal section through the membrance shown in FIG. 4 mounted on a cylindrical duct.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Reference will now be made in detail to the present preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings.
FIG. 1 shows a vertical section through a two-way bass reflex speaker system 10, comprising a speaker cabinet 11, a bass/midrange driver 12, a high frequency driver ("tweeter") 16, and a port 19. For the sake of clarity, components of a bass reflex speaker that do not relate to the invention, such as crossover filters for the driver 12 and tweeter 16, electrical wiring, and damping material for the speaker cabinet, are not shown in FIG. 1.
The bass/midrange driver 12 has a speaker cone 13 driven by a voice coil (not shown) in a magnet structure 14, which is supported by an acoustically open metal basket 15. The open end of the speaker cone 13 is connected to the basket 15 via a soft ring called a surround, which forms a seal between the speaker cone 13 and the outside of cabinet 11, but allows in/out movement of the speaker cone. The surround usually has the shape of a half-toroid, so the material can roll instead of stretching when the speaker cone 13 moves. The narrow end of the speaker cone 13 is connected to the magnet structure via a membrance with concentric corrugations called a spider. The surround and the spider allow a pure in/out motion of the speaker cone, so that when the voice coil of driver 12 is connected to output terminals of an audio amplifier, the front of the speaker cone 13 radiates directly to the outside of the cabinet, while the rear of the speaker cone 13 radiates 180° shifted sound through the open basket into the enclosed cabinet 11. The tweeter 16 has a dome 17 driven by a voice coil (not shown) inside a magnet structure 18. The dome 17 is supported by a surround, but usually there is no spider. When the voice coil of the tweeter is connected to output terminals of an audio amplifier, the front of the dome 17 radiates directly to the outside of the cabinet. The rear of the dome 17 radiates into a closed chamber housing the magnet structure, so the tweeter does not affect the sound pressure inside the cabinet 11.
The inside of the cabinet 11 communicates acoustically with the outside only through the port 19, via an opening 22 in a duct 20 with wall 21 made of cardboard or plastic. The duct 20 and the interior of the cabinet form a Helmholtz resonator with a resonance frequency determined by the compliance of the air volume inside the cabinet 11 and the air mass inside the duct 20. The frequency response of the Helmholtz resonator, as measured at the port 19, will be as shown in FIG. 3. Sound with frequency f 0 , equal to the resonance frequency of the Helmholtz resonator, passes through the port 19 with a phase shift of 180°, so the sound pressure at frequency f 0 from the port adds directly to the sound pressure from the front of the speaker cone 13. Sound of all other frequencies are attenuated. By selecting a resonance frequency f 0 about 1/2 actave lower than the roll-off frequency of driver 12, it is possible to get flat response to a bass frequency 1/2 octave lower than for a speaker with a closed cabinet without need for increased amplifier power, which is the object of a bass reflex speaker system.
If the duct 20 had wall 21 which was solid, as is common in the art, the frequency response curve will be as shown by the solid line in FIG. 3. Two undesirable resonance peaks appear at frequencies f 1 and f 2 in this case. In a speaker system with f 0 =42 Hz using a duct 20 with length 250 mm and an inside diameter of 35 mm, resonance peaks were measured at f 1 =550 Hz and f 2 =1200 Hz when the duct 20 had a wall 21 which was solid. The velocity of sound in air at atmospheric pressure at 20° C. is 344 m/s, so sound at 550 Hz has a half-wave length of 313 mm, and sound at 1200 Hz has a half-wave length of 143 mm. The duct 20 is 250 mm long, which is close to one half-wave length and two half-wave lengths, respectively, at the two sound peaks. The two peaks at 550 Hz and 1200 Hz are thus clearly caused by standing waves in a duct 20 with a wall 21 which is solid.
The peak sound levels from the port 19 at frequencies f 1 and f 2 are much lower than the sound pressure from the front of the driver 12 at these frequencies, but in a high fidelity speaker system discrete peaks in the midrange are audible as coloration of the sound even at very low levels.
According to the invention, the standing waves in the duct 20 can be eliminated by using a duct 20 with wall 21 provided with additional openings 31, 32 covered by deflectable membrances 35, such as an elastic film, as shown in FIGS. 1 and 2. The frequency response of the Helmholtz resonator of the system of FIG. 1, with a duct 20 with film covered openings 31, 32 in the wall 21 is shown by the dotted line in FIG. 3. The peaks at 550 Hz and 1200 Hz are eliminated, and a much smoother frequency response is obtained throughout the midrange frequencies.
The openings 31, 32 are located close to where the peak pressure variations would appear in the duct 20 at the frequencies to be attenuated. Opening 31 is thus close to the 1/4 wave location at frequency f 1 , and opening 32 is close to the 1/4 wave location at frequency f 2 . The film 35 can be in the form of a flat sheet glued to the outside of wall 21 of the duct 20, as shown in FIGS. 1 and 2, or it can be made in the form of a sleeve threaded over the wall 21, with ties to keep it in place.
The film forming the membrances 35 should be sufficiently compliant to make each membrance act as an opening in the duct at frequencies f 1 and f 2 , but stiff enough to make the membrance act as a seal at the Helmholtz resonance f 0 . The acoustic impedance of a membrance with given compliance is inversely proportional to frequency, so the large ratio between f 1 or f 2 and f 0 makes it easy to achieve this effect. A thin latex film works well, but it tends to age and become brittle. A 0.025 mm thick polyurethane film, sold under the trade name Walopur, is stable over time, and was used in the speaker system with frequency response as shown by the dotted line in FIG. 3. Other suitable film materials are available on the open market.
Latex film has very little elastic damping, so it is necessary to add damping material to avoid uncontrolled oscillations of the film covering openings 31, 32 when latex film is used. This can be achieved by wrapping loosely twisted fibers of cotton or cotton-like material around the outside of duct 20 so it lightly touches the film over openings 31, 32. Other methods for adding damping to the film can be used in cases where the film material itself is insufficiently damped. Polyurethane film has sufficient inherent damping, so no external damping is required for this type of film.
The deflectable membrances 35 can also be made from a substantially inelastic material, such as shown in FIGS. 4 through 6. FIGS. 4-6 show an inelastic membrane 35 according to the invention, mounted on a cylindrical duct 20 with walls 21 again having openings. The inelastic membrane 35 has been made deflectable by means of a surround 36, which is formed around the periphery of the membrane 35. The surround 36 allows in/out deflection of the membrane 35 in the same way as the surround for an ordinary speaker cone. The surround 36 can be formed in the same material as the membrane, or it can be made of a different material by gluing to the membrane 35. Outside the surround 36 are sections 37 for mounting and sealing the membrane 35 with surround 36 to the wall 21 of the duct 20. The function of a deflectable membrane of the type shown in FIGS. 4-6 is the same as for a deflectable membrane formed by a simple elastic film, as described above with reference to FIGS. 1 and 2.
When the duct 20 is cylindrical, as shown in FIGS. 4-6, the mounting section 37 must be formed into a relatively complicated shape as shown in FIG. 6, because the entire surround 36 must lie in a plane to function properly. In cases where the duct 20 has a flat wall section, the mounting sections can be coplanar with the membrane 35 and the surround 36, so the movable membrane 35 with surround 36 and mounting section 37 can be formed very simply from a thin sheet of plastic material, for instance by hot pressing.
A deflectable membrane made from an inelastic material, as illustrated in FIGS. 4-6, is more complicated to make than a simple elastic film, but its cost is still very low, and it makes it possible to use a wide range of materials that are not available as elastic films.
The number of openings (31, 32) required in the wall 21 of the duct 20 will vary from case to case, depending on the length of the duct 20 and upper crossover frequency for the bass/midrange driver 12. One opening will suffice in many cases, and rarely will more than three openings be required. The invention is not limited to a certain number of openings.
Thus, it is intended that the present invention cover the modifications and variations in the bass reflex type speaker system in accordance with the invention within the scope of the appended claims and their equivalents and without limitation to the different environments. | A bass reflex speaker system with a ducted port which can be made without coloration in the mid frequency band of the speaker caused by standing wave resonances in the duct. The system includes one or more openings in the wall of the duct between the ends of the duct, and covering the openings with a deflectable membrane, such as a film of latex-like material, or a rigid membrane with a flexible surround. The additional openings prevent pressure build-up at a quarter wavelength location of undesirable standing waves, and thereby cancels the standing waves, but they do not affect the operation of the duct at the Helmholtz frequency of the bass reflex system. | 7 |
BACKGROUND OF THE INVENTION
The present invention relates generally to an electric power tool, and more particularly to an electric power tool with torque-dependent speed regulation.
There are various reasons, well known to those conversant with this art, why it is in many instances desirable to be able to obtain an automatic regulation of the speed of an electric motor in a power tool in dependence upon torque of the output shaft of the tool. Tools having torque-dependent speed regulation to meet the above requirement, are already well known in the art. However, in every instance of such prior-art tools the regulation of the motor speed in dependence upon the torque is carried out by a highly complicated electronic regulator. Evidently, complicated electronic equipment of this type is expensive and as a result the overall cost of the tool is similarly high. Moreover, such electronic equipment is sensitive and this, in combination with its complexity, has a disadvantageous effect upon the operational reliability of a tool provided with such an electronic speed regulator.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to overcome the disadvantages of the prior art.
More particularly, it is an object of the present invention to provide an improved electric power tool having torque-dependent speed regulation which is not possessed of these disadvantages.
In particular, it is an object of the invention to provide such an improved electric power tool wherein a torque-dependent speed regulation is achieved in a very simple and reliable manner.
A further object of the invention is to provide such a power tool wherein the torque-dependent speed regulation is achieved mechanically, rather than electronically.
In keeping with these objects, and with others which will become apparent hereafter, one feature of the invention resides in an electric power tool with torque-dependent speed regulation which, briefly stated, comprises an electric motor having a drive shaft, a driven output shaft, and transmission means for transmitting rotary motion from the drive shaft to the driven shaft. Mechanical means is provided which is responsive to changes in the torque of one of the shafts by varying the rotational speed of the electric motor.
The construction according to the present invention thus replaces the purely electronic torque-dependent speed regulation of the prior art devices with a simple electro-mechanical arrangement which makes it possible, inter alia, to select the motor speed at load so as to be the same as, greater than or smaller than the motor speed under no load conditions, depending upon the elasticity of a spring or the thread pitch of a bolt, both of which are components of the arrangement, as will be discussed subsequently. Moreover, in the arrangement according to the present invention a built-in safety factor exists inasmuch as no moment of torque will be transmitted in the event the aforementioned spring should break, therefore eliminating the possibility that the device might operate out of control.
The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawing.
BRIEF DESCRIPTION OF THE DRAWING
The single FIGURE is a longitudinal section through those portions of a tool embodying the present invention, which are of importance for an understanding of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now in detail to the drawing it will be seen that the electric power tool illustrated therein has a housing 10 which in this embodiment is composed of a plurality of housing portions that are connected with one another in suitable manner. Located substantially at the center of the housing 10 is an electro-motor 11 of the type whose speed can be varied, that is increased or decreased. The electric-motor 11 has a driven shaft or output shaft 12 which is composed of a plurality of shaft portions and on which a gear 13 -- in this embodiment configurated as a bevel pinion -- is turnably mounted. The gear 13 meshes with a similarly bevelled gear 14 which is fixedly mounted on an output shaft or work spindle 15 that is journalled for rotation in the housing 10, so that an angle drive is obtained. It will be appreciated that the invention would also be applicable to an arrangement which does not have an angle drive and/or wherein the gears are not bevelled.
The pinion 13 is potentially freely turnable on the shaft 12, but is connected with the same by means of a helical spring 16 one end of which extends into and is secured in a recess or bore 17 formed at the left-hand axial end face of the shaft 12, whereas the other end of the spring 16 extends into and is secured in a longitudinal slot 18 formed in an extension 13' of the pinion 13. Thus, the pinion 13 is connected with the shaft 12 for rotation with the same, but has freedom of turning angularly with reference to the shaft 12 through a certain extent which is determined by the elasticity of the spring 16.
A tapped bore 20 is formed in the shaft 12, extending inwardly from the left-hand end of the same in the drawing, and a threaded bolt 21 is threaded into the tapped bore 20. The spring 16 surrounds the bolt 21 which latter extends outwardly beyond the end face of the shaft 12 by a significant amount and carries at its own end that is directed towards the spindle 15 a projection or pin 22 which extends into the same slot 18 into which one end of the spring 16 is hooked. This means that the bolt 21 turns with the pinion 13 and cannot turn relative to it, but does have freedom of axial displacement to a limited extent.
The shaft 12 is formed over its entire axial length with a bore 23 in which a rod 24 is slidably accommodated which is firmly connected with the bolt 21. It is advantageous if the rod 24 is of a synthetic plastic material, for instance nylon or the like, to facilitate its sliding since nylon has a low coefficient of friction. The rod 24 projects outwardly beyond the shaft 12 at its right-hand end, that is the end which is remote from the spindle 15, and there carries a metallic body 25 which is ring-shaped in this embodiment and is configurated of iron or is configurated of a permanently magnetic material. This ring 25 extends with clearance into the yoke 26 of an electrical winding or coil 27 which in turn is connected with a electronic control unit 28 which is very simple in its construction and well known in the art. The electronic control unit 28 comprises an output transistor 29, an amplifier 30 connected to the output of the transistor, and a potentiometer 37 which regulates the motor current. It is this control unit which in turn is connected with the motor 11 to vary the rotational speed of the same in dependence upon signals resulting from a coaction of the ring 25 and the spool 27 with its yoke 26.
In operation of the arrangement illustrated in the drawing, the torque of the motor 11 is transmitted via the shaft 12 and the spring 16 to the pinion 13. Since the pinion 13 meshes with the gear 14, the torque is transmitted to the latter and from the same to the output spindle 15. Depending upon the torque prevailing at any moment, the pinion 13 can turn angularly with reference to the driven shaft 12 to a greater or lesser degree, within a certain range, the degree being determined by the prevailing torque. This relative displacement of pinion 13 to shaft 12 causes an axial displacement of the bolt 21 with reference to the shaft 12, in that the bolt 21 is either threaded deeper into the tapped bore 20 or is threaded farther out of the same. In so doing the bolt 20 shifts the rod 24 axially of the latter, either towards the right or towards the left in dependence upon the direction in which the bolt 21 is turned, and this changes the position of the ring 25 with reference to the yoke 26 and coil 26 through which current flows. This in turn varies the magnetic flux or the induced current, and produces a signal which is used to control the speed of the motor 11 via the simple aforementioned electronic control device.
It should be understood that the ring 25 can itself be constructed as a current-carrying coil which influences the induced current in the coil 27.
In dependence upon the elasticity of the spring 26 or the pitch of the internal thread in the tapped bore 20 and the thread on the bolt 21, the actual rotational speed of the motor, beginning with the no-load speed, can be selected to be unchanged, to increase or decrease. In the event that the spring 16 should break, no torque will be further transmitted so that this acts as a safety arrangement.
It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of constructions differing from the types described above.
While the invention has been illustrated and described as embodied in an electric power tool, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.
Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention. | An electric motor of the tool has a drive shaft and in turn drives an output shaft by means of a gear transmission. A mechanical arrangement senses the torque of the drive shaft of the motor and varies the supply of electrical energy to the motor in dependence upon changes in the torque. | 8 |
BACKGROUND OF THE INVENTION
The present invention pertains to testing, diagnosing and repairing printed wiring cards and more particularly to testing the bus leads of printed wiring cards which utilize bus structured components.
In the manufacture of complex bus structured printed wiring cards (PWC), the signal leads of each bus are closely spaced and cover a considerable of such printed wiring cards have elaborate bus structures on both sides of the PWC. These bus structures often pass beneath the components of the printed wiring card.
As a result of the wave solder process in the fabrication of printed wiring cards, these buses often contain solder shorts (unintended connection between the signal leads). One previous method of detecting such solder shorts include visual inspection with the aid of high magnification. Another method of detecting the shorts employs an ohm meter to check the resistance between a particular signal lead and every other signal lead to insure that no unintended connections have been made. These manual methods are time consuming and error prone.
Some printed wiring card testing involves the generation of complex computer generated algorithms. The process of generating the software which employs these algorithms is expensive for testing small numbers of various kinds of printed wiring cards.
Accordingly, it is the object of the present invention to provide an inexpensive, quick and relatively error free apparatus for automatically testing the bus structure of various printed wiring cards for electrical shorts.
SUMMARY OF THE INVENTION
In accomplishing the objects of the present invention, there is provided a novel circuit for automatically testing the bus structure of a printed wiring card for electrical shorts.
This circuitry for testing the bus structure of a printed wiring card includes a pattern generator which is cyclically operated to produce pluralities of logic values for each lead of an address bus and a data bus. These address and data buses correspond to the bus structure of the printed wiring card which is to be tested.
This circuitry also includes a memory scheme which is connected to the pattern generator via address and data bus leads. This memory scheme is operated to store two copies of the pluralities of logic values produced by the pattern generator. The values of the data bus are stored at a location in the memory scheme corresponding to the values of the address bus. A connection arrangement connects the address and data bus structure of the printed wiring card undergoing test to the address bus and data bus leads of the memory scheme. This connection arrangement permits the logic values of the address and data buses of any shorted leads of the bus structure of the printed wiring card to affect the address bus connected to the memory scheme.
Lastly, a detection circuit is connected to the pattern generator and to the memory scheme. This detection circuit operates to compare the two stored copies of logic values and to indicate the identity of any faulty leads of the bus structure of the printed wiring card based upon an analysis of the memory contents.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of the circuit for testing the bus structure of a printed wiring card.
FIG. 2 is a physical layout view of the circuit and its associate apparatus for testing the bus structure of a printed wiring card.
DESCRIPTION OF THE PREFERRED EMBODIMENT
A two (2) mehahertz clock 10 is connected to counter 15 and generates all the signals of the bus testing circuit. Counter 15 is a 22 bit binary counter whose output lines 0-15 provide the pattern generator 25 with a set of address inputs. Output bits 17 through 20 of counter 15 are also connected to pattern generator 25. Bits 17 through 20 provide for selecting the pattern number which indicates the pattern input as data to memories 55 and 60 (See table 1).
Bits 0 through 15 output by counter 15 are also transmitted via connections to buffer register 35. In response to memory control 20, the outputs of buffer register 35, bits 0-15 of counter 15 which are buffered, are clocked to memory 55. The outputs of buffer register 35 are used as an input address to memory 55. Bits 17 through 20 of counter 15 are transmitted to memory control 20 and to pass/fail control and monitor 77. Bit 16 of the output of counter 15 is also transmitted to memory control 20.
The read/write signal is transmitted from memory control 20 to memories 55 and 60 via the R/W leads. This signal is derived from bit 16 of counter 15. The R/W bus is also connected to compare circuit 65.
Output bits 17 through 20 of counter 15 are transmitted to address drivers 40. Address drivers 40 provide additional drive for these signals. The output of address drivers 40 is connected to address select switch 30. Each of the leads of the particular bus under test is connected to low pass filter 45 and to AND gate 32. Address select switch 30 controls gate 32 to transmit the address or data from buffer register 35 to memory 60. Gate 32 also transmits the bus under test leads to memory 60. As it will be shown later, this combining of the address and data written to memory 60 with the address and data of the bus under test is the key to the fault detection.
Memories 55 and 60 are connected to compare circuit 65 via their respective DATA OUT leads. The address and data buses are transmitted from buffer register 35 to OR gate 70. OR gate 70 is connected to error N detect circuit 80. The output of compare circuit 65 is connected to both error 1 detect circuit 75 and to error N detect circuit 80.
OR gate 70 is a 16 input OR gate. The data and address buses are time multiplexed through it. OR gate 70 may be implemented with a number of standard integrated circuits including: a five input NAND gate integrated circuit part no. 74LS20; an OR gate part no. 74LS32; an AND gate part no. 74LS08; two NOR gates part no. 74LS02; and three four input NOR gates part no. 74LS25.
Compare circuit 65 is also connected to pass/fail control and monitor 77. Monitor 77 indicates whether the tests pass and whether the address or data bus has failed, if a failure occurs.
Counter 15 is connected via the 4-bit bus bits 17-20 to display 97. In addition, error 1 detect 75 is also connected to display 97. Error detect 75 detects the first bus shorting error and displays via display 97 the indication of the identity of this short.
Error N detect circuit 80 is connected to serial to parallel shift register 99. Detect circuit 80 detects errors in buses under test after the first error has been detected by error 1 detect circuit 75. Error and detect circuit 80 detects the next five errors. Therefore, six errors in total may be detected by this circuitry.
Serial to parallel shift register 99 is connected via a 5-bit bus to display 98. Display 98 is also connected to counter 15 via bits 1-20.
In response to the reset signal to counter 15, this circuit clears itself by zeroing out memories 55 and 60. During this process, bits 17 through 20 output by counter 15 are at logic 0 or low. As a result, the address drivers 40 and the address select switch 30 provide memories 55 and 60 with identical addresses. The data supplied during this initial write cycle is zero. Each of the 1024 locations of each memory are thereby cleared or set to zero.
During the test cycle, the connection of the bus under test will be "ANDed" with the values of the address select switch 30 by gate 32. The particular bus structure under test will be connected via low pass filter 45, through AND gate 32 to memory 60.
If two bus lines are shorted together, and a logic 0 (low or ground) is applied to one bus lead and logic 1 (high or voltage) is applied to the other lead, both shorted leads will experience a logic 0.
Because of the gating action of AND gate 32, words written to memory 60 via address select switch 30 and AND gate 32 will be affected by any shorts on the leads which comprise the bus under test. For example, if a short exists on two of the leads comprising the address portion of the bus under test, for a particular address pattern through gate 32 to memory 60, any shorted logic ones will become logic zeroes. As a result, the data will be written at the incorrect address. On subsequent comparison of memories 55 and 60 by compare circuit 65, the memories will miscompare at this particular address. Based upon the numeric value of the address of the miscomparison, a detection will be made as to which address leads are shorted. This detection will be transmitted to error 1 detect circuit 75, where it will be latched and displayed by display 97. Display 97 is the first segment of a multiple segment NIXI tube display.
For detecting errors 2 through 6, are detected by the error N detect circuit 80. The address and data bus leads are transmitted via OR gate 70 to error N detect 80 which detects errors subsequent to the first error. For each subsequent error, the identity of the shorted lead is transmitted to serial to parallel shift register 99. Each of the following five errors is transmitted to shift register 99. When all 5 errors have been detected shift register 99 transmits them to NIXI display 98.
In addition to displaying the identity of the shorted address or data bus leads, LEDS 92, 93 and 94 provide a visual indication of the status of a bus under test as either passing or failing the examination. In response to compare circuit 65, pass/fail control and monitor 77 will either light LED 94 via the pass signal or for a failure light either LED 92 or 93 corresponding to address and data lead failures via the corresponding address fail and data fail leads.
The bus under test lead is connected via a clip arrangement 100 to the particular bus structure to be tested. See FIG. 2. Several patterns are written into memories 55 and 60. Because of the connection to the bus under test through gate 32, shorts will be detected by the following process.
Bus leads that are shorted will produce the same logic value, if a signal is applied to one lead. When a logic 0 is applied to one of the short leads and a logic 1 is applied to the other of the shorted leads, the lead with the logic 1 will be "pulled down" by the shorted logic 0 lead to a logic 0. As a result, when this combination is gated through gate 32, the address bus of memory 60 will be affected and data will be written at an incorrect address. Subsequently, when compare circuit 65 compares the contents of memories 55 and 60, a miscomparison at this address will be detected and the appropriate error detector circuit enabled and its corresponding display turned on. In addition, the pass/fail control and monitor 77 will light the appropriate LED 92 through 94.
Table 1 depicts the contents of the memory 60 which result from a short on address bus leads A1 and A2. For purposes of illustration, only the first four address bits (A0-A3) of the address bus are shown.
TABLE 1______________________________________ Data In Data OutPattern # . . . 4 3 2 1. . .A15 . . . A3 A2 A1 A0 00 01 02 03______________________________________ 0 0 0 0 0 0 0 0 1 0 0 0 1 0 0 0 0 0 0 1 1 1 1 0 1 0 0 0 1 0 0 0 0 0 1 0 x x x x 0 0 1 1 x x x x 0 1 0 0 x x x x 0 1 0 1 x x x x 0 1 1 0 0 1 1 0 0 1 1 1 1 1 1 0 1 0 0 0 0 0 0 0 1 0 0 0 l 1 1 1 1 0 0 1 1 1 1 0 1 0 0 0 1 1 1 1 1 0 1 0 x x x x 1 0 1 1 x x x x 1 1 0 0 x x x x 1 1 0 1 x x x x 1 1 1 0 0 1 1 1 1 1 1 1 1 1 1 1______________________________________
Patterns 0 and 3 ignore any shorted type faults on bus leads 1 and 2, even though certain memory locations within memory 60 are over written. Patterns 1 and 2 will detect shorts on bus leads 1 and 2. This true for either the address or data buses.
In general, if N is the number of the shorted bus element and a pattern which is not equal to N is applied to memories 55 and 60, then the data read by compare circuit 65 will be correct and it will appear that no short exists. Therefore, short type faults will be detected on bus lead N only by pattern N. There is a one to one correspondence between a pattern number and the bus lead assignment number.
When the first fault is detected by compare i circuit 65, error 1 detect circuit 75 generates a latch signal which is transmitted to display 97. Display 97 decodes and latches the value of bits 17 through 20 of counter 15. These bits correspond to the pattern number.
For succeeding faults, OR gate 70 decodes the address. Error N detect circuit 80 then provides a clock signal to serial to parallel shift register 99. The outputs of register 99 provide signals to the display circuit 98. As a result the number of each subsequent error pattern is latched and displaced by display 98.
FIG. 2 depicts a physical view of the circuitry, its housing and interface components. Clip 100 is a 40 pin integrated circuit clip mounted at one end of a 40 conductor ribbon cable. The other end of the ribbon cable is connected to the circuitry as shown in the schematic of FIG. 1, as a bus under test. Clip 100 is mounted directly on the central processor unit of the circuit to be tested. In this way, all of the address and data leads of the circuit may be transmitted to the test circuitry from a common point. The clip may be connected to any device which has all the address and data leads connected to it. The test consists of 16 patterns and is performed in two parts. The first part is the address line verification and the second part is the data line verification. This circuit contains 24 open collector test leads. Sixteen of these test leads are used for testing the address portion and eight are used for testing the data portion. However, different size address and data buses may be tested, so long as there are no more then 24 total address and data leads. This circuitry is not restricted to the particular combination of 16 address leads and 8 data leads. It is to be noted that clip 100 may not be placed to access any circuit modes which include pull up resistors. These modes would appear as high impedance links to voltage. As a result a display would incorrectly indicate these notes as being shorted leads.
Again referring to FIG. 2, to initiate the testing procedure, the power switch is turned on. Next, the clip is attached to the microprocessor of the circuit to be tested. The clip may also be attached to another device which has all the address and data leads connected to it. Then, the CLEAR switch is pushed to reset the unit. The TEST pushbutton is depressed to begin testing.
The address testing is preformed first. Then the data leads are tested. If no faults were detected, the pass LED 94 is lighted. The hexadecimal display CHANNEL ERROR is associated with the address or data lead which failed, depending on the particular LED indicator which is lit (92 or 93).
Although the preferred embodiment of the invention has been illustrated, and that form described in detail, it will be readily apparent to those skilled in the art that various modifications may be made therein without departing from the spirit of the invention or from the scope of the appended claims. | This circuit provides for testing the bus structure (address and data buses) of a printed wiring card. This circuit provides an inexpensive means for off line detection of low impedance paths between leads of bus oriented printed wiring cards. This circuit is particularly useful for testing high lead density printed wiring cards, such as, microprocessor or memory related printed wiring cards. This circuit automatically tests all possible combinations of bus leads for a shorted fault condition. This circuit operates without the application of any power to the printed wiring card to be tested. For the detection of any shorted fault leads, the identity of the shorted leads is displayed visually. In addition, for a shorted fault lead, a determination is made as to whether the shorted leads are address bus leads or data bus leads. A visual display indicates whether the particular printed wiring card has successfully passed all the tests | 6 |
FIELD OF INVENTION
This invention relates to blocks and retaining walls suitable for gardens and other small non-construction sites.
BACKGROUND OF INVENTION
Small retaining walls for gardens and other sites of similar dimensions and requirements, are ideally constructed simply and with minimum equipment.
SUMMARY OF INVENTION
According to this invention, there is provided a block for forming a retaining wall comprising: (a) a body with front, rear, top, bottom and side surfaces and a central cavity with internal walls; (b) projecting means integrally formed on said bottom surface proximate said front surface and being laterally offset from said cavity and rearwardly offset from the front of the cavity and having a rounded front surface.
According to another aspect of this invention, there is provided a retaining wall comprising: (a) a lower row of blocks arranged side by side, each block having a body with a cavity and a rear surface; (b) an upper row of blocks arranged side by side, each block having a body with a cavity and projecting means integrally formed on said bottom surface, whereby said projecting means abut the rear surfaces of proximate block of the lower row.
BRIEF DESCRIPTION OF DRAWINGS
Advantages of the present invention will become apparent from the following detailed description taken in conjunction with preferred embodiments shown in the accompanying drawings, in which:
FIG. 1 is a plan view of a block according to the invention;
FIG. 2 is a side view of the block of FIG. 1;
FIG. 3 is a plan view of a second embodiment of the block of the invention;
FIG. 4 is a side view of the block of FIG. 3;
FIG. 5 is a perspective view of the block of FIGS. 1 and 2;
FIG. 6 is a perspective view of a wall formed of the block of FIG. 5; and
FIG. 7 is a perspective view of a variation of the wall of FIG. 6.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIGS. 1, 2 and 5 show a first embodiment of a block 2 for forming a retaining wall. Block 2 includes spaced front and rear wall portions 4 and 6 respectively. A pair of side walls 8 extend between and join the front and rear wall portions to define a central open cavity 10 through the block having internal side walls 11, internal front wall 13 and internal rear wall 17. The block has upper surface 12 and a lower surface 14. Block 2 is preferably formed from concrete and the face of front wall portion 4 is formed with a roughened pattern 16. Block 2 has a generally trapezoidal shape in plan view with the wall portion 4 wider than the rear wall portion 6.
Rear wall portion 6 of block 2 includes a frangible extension 28 that extends beyond sidewalls 8. Extensions 28 can be broken off along pre-formed fault lines 29 (e.g. by a hammer) so that block 2 is reduced to essentially an arcuate segment. Such a block 2 can then be rotated to a desired angle to form a curved retaining wall, as shown in FIG. 7 described below.
Block 2 is provided with projecting means in the form of a pair of spaced, cylindrical extensions or knobs 18. Knobs 18 are integrally formed on the lower surface 14 of side walls 8 behind the front edge of cavity 18. Although knob 18 is shown to be cylindrical, it need only have a front curved surface to be able to rotate and accommodate a desired curved configuration of retaining wall, or could have a flat front surface if non-curved configurations are sufficient. Although knob 18 is shown to be positioned proximate the front edge of cavity 18, knob 18 can be positioned farther rearwardly. The extent that knob 18 is positioned behind the front edge of cavity 18 determines the rearward offset of the wall constructed, as described below.
FIGS. 6 and 7 show retaining walls constructed with the foregoing described first embodiment of blocks 2. A first row of blocks 2 is laid on the ground or in a shallow trench dug in the ground. Blocks 2 are backfilled with soil 99 and cavities 10 are filled with soil or loose angular gravel and dirt, to anchor the row of blocks 2, to permit drainage of water therethrough, and to permit plants and flowers to be planted therein. After completion of the first row and backfilling as described, a second row of blocks 2 is laid. The blocks 2 of the second row are laterally offset from the blocks 2 of the first row. In particular, a block 2 of the second row is positioned in approximately half bond relationship to two underjacent blocks 2 of the first row (i.e. the upper block 2 is centered approximately at the plane of contact between the two underjacent blocks 2. The two knobs 18 of a block 2 of the second row abut the respective rear wall portions 6 of the two adjacent blocks 2 of the first row. One such abutment of knob 18 is shown in FIG. 6. Thus formed, the second row of blocks 2 are rearwardly offset from the first row of blocks 2. Then the blocks 2 of the second row are backfilled and filled, and the above process is continued for perhaps several more rows for a common garden setting.
FIG. 7 shows an arcuate wall of blocks 2 where the frangible extensions 28 have been removed.
FIGS. 3 and 4 show a second embodiment of block 2 having generally larger dimensions than those of the first embodiment. A reinforcing web 15 is provided between side walls 8 at substantially mid-length therealong to form front and rear internal cavities 10 and 10a. The blocks of FIGS. 3 and 4 are used for larger retaining walls because their additional size and mass allows them to support a greater bulk of soil. The method of creating retaining walls described above for the first embodiment of block 2, is applied to the second embodiment of block 2. One variation (not shown) is that knobs 18 may abut the rear wall portion 6 or be inserted into rear internal cavity 10a and abut a front surface thereof, thus allowing a variation in the rearwardly offset of superjacent rows of blocks 2. In contrast, a wall employing the first embodiment of block 2 will have a uniform rearwardly offset between superjacent rows.
Typical dimensions of the fist embodiment of block 2 are 4" high by 12" wide by 8" deep with knobs 0.5" high and 2.5" in diameter if the knob is cylindrical. It will be appreciated that the dimensions given are merely for purposes of illustration and are not limiting in any way. The specific dimensions given may be varied in practising this invention, depending on the specific application.
While the principles of the invention have now been made clear in the illustrated embodiments, there will be immediately obvious to those skilled in the art, many modifications of structure, arrangements, proportions, the elements, materials and components used in the practice of the invention, and otherwise, which are particularly adapted for specific environments and operational requirements without departing from those principles. The claims are therefore intended to cover and embrace such modifications within the limits only of the true spirit and scope of the invention. | A block useful for constructing retaining walls for gardens, has two bottom lugs or knobs, bracketing an internal cavity. The cavity may be filled with soil. In forming a wall, the upper row of blocks is rearwardly onset from the lower row of blocks, whereby the lugs of the blocks of the upper row abutting the back surfaces of the blocks of the lower row. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a liquid crystal panel, and more particularly, to a liquid crystal-on-silicon (LCoS) panel utilizing one or multiple spacer walls and one-drop-fill technology.
2. Description of the Prior Art
Liquid crystal-on-silicon (LCoS) micro-display panel is arguably the heart of the reflective LCoS projectors and rear-projection televisions. The LCoS micro-display devices are tiny, less expensive, and have high resolution. As known in the art, the difference between a LCoS micro-display and a conventional thin film transistor-liquid crystal display (TFT-LCD) is materials used for forming substrates. Both of a cover and a backplane are made of glass in a TFT-LCD, nevertheless, the cover in a LCoS display is made of glass, but the backplane in a LCoS display is a semiconductor silicon substrate. Therefore, a LCoS process combines LCD techniques and complementary metal-oxide semiconductor (CMOS) processes.
Please refer to FIG. 1 and FIG. 2 , wherein FIG. 1 is a schematic top view of a LCoS panel 10 according to the prior art and FIG. 2 is a schematic cross-sectional view of the LCoS panel 10 taken along line I-I of FIG. 1 . The prior art LCoS panel 10 comprises a silicon substrate 12 used as a backplane and a glass substrate 16 being composed of, for example, indium tin oxide (ITO) glass. The silicon substrate 12 further comprises a plurality of pixel arrays (not explicitly shown) formed on its display active region 14 . A liquid crystal layer 18 is sealed between the silicon substrate 12 and the glass substrate 16 . Spherical spacers 22 of approximately equal size are disposed between the silicon substrate 12 and the glass substrate 16 . In addition, a plurality of bonding pads 122 are formed on the longer side of the silicon substrate 12 used for soldering up the backplane and the cover in subsequent processes.
In LCD devices, the thickness of the liquid crystal layer 18 , or the cell gap (i.e., the space between a transparent conducting substrate and a semiconductor substrate) has to be precisely controlled to a specific value so as to ensure the display performance. In order to maintain the cell gap, plastic beads, glass beads or glass fibers are normally interposed between two liquid crystal display substrates and used as spacers. Thus, this cell gap is defined by the spacer height. In a conventional LCD process, the spacers are positioned by spraying, so the positions between the two liquid crystal display substrates cannot be controlled accurately. Consequently, the display performance of the liquid crystal display device is affected due to light scattering by the spacers that are present in the light transmitting regions. Furthermore, the spacers tend to be mal-distributed so that the display performance in portions of the LCD with spacers bunched is impaired, and the uniformity of the cell gap cannot be precisely maintained.
According to the prior art, seal glue 20 is applied to the periphery of the display active area 14 of the silicon substrate 10 . The seal glue 20 has a slit or break in it for liquid crystal injection in the subsequent processes. The prior art LCoS panel 10 has a drawback in that the design width of the seal glue 20 is about 2000 micrometers and the design width is about 500 micrometers, which occupy a large chip surface area. Further, in the traditional LC injection method, the cell will be vacuum filled by capillary attraction after the glass substrate 16 and the silicon substrate 12 are assembled. Such injection method has the drawbacks of wasting time and liquid crystal material.
SUMMARY OF THE INVENTION
Accordingly, it is the primary object of the present invention to provide an improved LCoS panel and method of making in order to solve the above-mentioned problems.
According to the claimed invention, a liquid crystal panel includes a first substrate having thereon a display active region; an inner spacer wall disposed on the first substrate along periphery of the display active region; an outer spacer wall disposed adjacent to the inner spacer wall on the first substrate, wherein the inner spacer wall and the outer spacer wall are of approximately equal height; a groove formed between the inner spacer wall and the outer spacer wall; a seal spread in the groove; a second substrate being supported by the inner spacer wall and the outer spacer wall and being glued to the first substrate via the seal, wherein the first substrate, the second substrate and the inner spacer wall define a chamber; and a liquid crystal layer filling the chamber by using one-drop-fill process.
According to another preferred embodiment, a method of fabricating a liquid crystal panel is disclosed. The method comprises the following steps:
(a) providing a first substrate comprising thereon a display active region;
(b) depositing a dielectric layer over the first substrate by using various deposition methods;
(c) etching a portion of the dielectric layer to expose the display active area and to form an inner spacer wall and an outer spacer wall enclosing the display active region, and a groove between the inner spacer wall and the outer spacer wall, wherein the inner spacer wall and the outer spacer wall are of approximately equal height;
(d) spreading seal in the groove;
(e) performing an one-drop-fill process to dispose drops of liquid crystal on the display active region within the inner spacer wall;
(f) placing a second substrate on the first substrate, wherein the second substrate is supported by the inner and outer spacer walls and is glued to the first substrate via the seal; and
(g) curing the seal.
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
The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention. In the drawings:
FIG. 1 is a schematic top view of a liquid crystal-on-silicon (LCoS) panel according to the prior art;
FIG. 2 is a schematic cross-sectional view of the LCoS panel taken along line I-I of FIG. 1 ;
FIG. 3 is a schematic top view of a LCoS panel according to one preferred embodiment of the present invention;
FIG. 4 is a schematic cross-sectional view of the LCoS panel taken along line II-II of FIG. 3 ; and
FIG. 5 to FIG. 9 are schematic, cross-sectional diagrams showing the method of fabricating a LCoS panel with dual spacer walls in accordance with one preferred embodiment of this invention.
DETAILED DESCRIPTION
Please refer to FIG. 3 and FIG. 4 , wherein FIG. 3 is a schematic top view of a LCoS panel 50 according to one preferred embodiment of the present invention and FIG. 4 is a schematic cross-sectional view of the LCoS panel 50 taken along line II-II of FIG. 3 . The LCoS panel 50 comprises a silicon substrate 52 used as a backplane, and a glass substrate 56 being composed of, for example, indium tin oxide (ITO) glass. The silicon substrate 52 further comprises a plurality of pixel arrays (not explicitly shown) formed on its display active region 54 . A liquid crystal layer 58 is sealed between the silicon substrate 52 and the glass substrate 56 .
It is one salient feature of the invention that the display active region 54 of the silicon substrate 52 is surrounded by dual spacer walls including an inner spacer wall 62 and an outer spacer wall 64 . According to the preferred embodiment of this invention, the inner spacer wall 62 and the outer spacer wall 64 are two parallel walls of approximately equal height. A groove 66 is provided in between the inner spacer wall 62 and the outer spacer wall 64 for accommodating seal 70 . The groove 66 also increases the effective contact area between the seal 70 and the silicon substrate 52 such that the adhesion is improved. The inner spacer wall 62 and the outer spacer wall 64 have a flat top surface 62 a and a flat top surface 64 a , respectively. In addition, the plural bonding pads 522 are disposed on the shorter side of the silicon substrate 52 .
According to this invention, the inner spacer wall 62 and the outer spacer wall 64 are fabricated at the last stage of the fabrication processes for making the silicon substrate 52 . The inner spacer wall 62 and the outer spacer wall 64 are fabricated and defined along the periphery of the display active region 54 by using standard semiconductor processes such as chemical vapor deposition (CVD) methods, chemical mechanical polish (CMP), lithography and etching. According to the preferred embodiment, the inner spacer wall 62 and the outer spacer wall 64 are made of dielectric materials such as silicon dioxide, but not limited thereto.
In typical LCD devices, as mentioned above, spherical spacers such as plastic beads or glass beads are dispersed randomly on the entire silicon substrate, even in the display active region or viewing areas, or mixed with the glue seal. However, spacers in the viewing area of a display frequently lead to the reduced contrast of the display. In the present invention, the plastic beads or glass beads are not used and are replaced with the dual spacer walls, i.e., the inner spacer wall 62 and the outer spacer wall 64 . By doing this, the cell gap is effectively controlled so as to assure the proper operation of the LCD devices. Since the conventional spherical spacers such as plastic beads or glass beads are omitted, the cost of the panel product can be reduced.
As shown in FIG. 4 , it is another salient feature of the invention that by using the dual spacer walls, the design width of the seal 70 shrinks from 2000 micrometers to about 500 micrometers. By shrinking the design width of the seal 70 , the surface area of each panel can be reduced and the number of the panels of each wafer is increased.
Please refer to FIG. 5 to FIG. 9 . FIG. 5 to FIG. 9 are schematic, cross-sectional diagrams showing the method of fabricating a LCoS panel with dual spacer walls in accordance with one preferred embodiment of this invention. As shown in FIG. 5 , a wafer or silicon substrate 152 having thereon a display active region 154 is provided. The display active region 154 has therein an integrated control circuit, electrodes connected to the integrated control circuit, and metal mirror plates for reflecting light (not explicitly shown). It is understood that the integrated control circuit may comprises an array of transistors such as MOS transistors. A chemical vapor deposition process is carried out to deposit a silicon dioxide layer 112 over the silicon substrate 152 . The thickness of the silicon dioxide layer 112 is approximately equal to the cell gap of the LCoS panel. Thereafter, a photoresist pattern 114 , which defines the position and pattern of the dual spacer walls to be etched into the underlying silicon dioxide layer 112 , is formed over the silicon dioxide layer 112 . According to another embodiment, prior to the deposition of the silicon dioxide layer 112 , a protective film or an alignment film may be deposited over the silicon substrate 152 .
As shown in FIG. 6 , using the photoresist pattern 114 as an etching hard mask, an anisotropic dry etching process is carried out to remove the silicon dioxide layer 112 that is not covered by the photoresist pattern 114 until the silicon substrate 152 is exposed, whereby forming the dual spacer walls 160 enclosing the display active region 154 . The dual spacer walls 160 includes an inner spacer wall 162 and an outer spacer wall 164 . The photoresist pattern 114 is then stripped. According to this invention, the inner spacer wall 162 and the outer spacer wall 164 are both continuous walls and have no break or slit. The inner spacer wall 162 minimizes the contact between the seal and the liquid crystal, thereby preventing potential pollution of the liquid crystal.
Since the inner spacer wall 162 and the outer spacer wall 164 are fabricated by standard semiconductor processes, the deviation of the height of the spacer walls is very small. The cell gap between the silicon substrate 152 and glass substrate is effectively controlled so as to assure the proper operation of the LCD devices. A groove 166 is formed between the inner spacer wall 162 and the outer spacer wall 164 . As previously described, the groove 166 is used to accommodate seal and to increase the contact between the silicon substrate 152 and the seal.
As shown in FIG. 7 , after the formation of the dual spacer walls 160 , one-drop-fill (ODF) process is carried out to form liquid crystal drops on the silicon substrate 152 . The ODF process is to drop the liquid crystal 158 directly on display active region 154 within the inner spacer wall 162 . The ODF Process is a technology currently developed in the LCD field. With the utilization of this state-of-the-art technology, it increases the efficiency in the manufacturing of large sized panel. The ODF Process can save a great deal of time and liquid crystal material that has a competitive edge particularly for large size panel. For example, it requires about 5 days to fill the liquid crystal for a 30 inches panel according to the traditional vacuum suction method, but it only needs 5 minutes by adoption of the ODF method. Thereby the consumption of liquid crystal material can be reduced to approximately 40% as compared to the traditional method.
As shown in FIG. 8 , seal 170 is provided in the groove 166 between the inner spacer wall 162 and the outer spacer wall 164 under vacuum environment or reduced pressure. It is noteworthy that the volume of the seal 170 spread in the groove 166 is slightly greater than the space of the groove 166 . According to the preferred embodiment of this invention, the seal 170 may be photo hardening seal, ultraviolet-type seal or thermal hardening seal.
Finally, as shown in FIG. 9 , a glass substrate 156 is glued together with the silicon substrate 152 via seal 170 to form panel assembly. The glass substrate 156 is in parallel with the silicon substrate 152 . The panel assembly is then subjected to ultraviolet to cure the seal 170 . In another case, the panel assembly is treated with thermal process to harden the seal 170 . The panel assembly is then cut into panel die by using conventional methods.
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. Accordingly, the above disclosure should be construed as limited only by the metes and bounds of the appended claims. | A liquid crystal panel includes a first substrate having thereon a display active region; an inner spacer wall disposed on the first substrate along periphery of the display active region; an outer spacer wall disposed adjacent to the inner spacer wall on the first substrate; a groove formed between the inner spacer wall and the outer spacer wall; a seal spread in the groove; a second substrate being supported by the inner spacer wall and the outer spacer wall and being glued to the first substrate via the seal, wherein the first substrate, the second substrate and the inner spacer wall define a chamber; and a liquid crystal layer filling the chamber by using one-drop-fill process. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the priority of co-pending Australian Patent No. 2003903576, entitled “Audio Path Diagnostics,” filed Jul. 11, 2003. The entire disclosure and contents of the above application is hereby incorporated by reference herein.
[0002] This application is related to U.S. Pat. Nos. 4,532,930, 6,537,200, 6,565,503, 6,575,894, and 6,697,674. The entire disclosure and contents of the above patents are hereby incorporated by reference herein.
BACKGROUND
[0003] 1. Field of the Invention
[0004] The present invention relates generally to audio signal processing and, more particularly, to audio path diagnostics.
[0005] 2. Related Art
[0006] The use of patient-worn and implantable medical devices to provide therapy to individuals for various medical conditions has become more widespread as the advantages and benefits such devices provide become more widely appreciated and accepted throughout the population. In particular, devices such as hearing aids, implantable pacemakers, defibrillators, functional electrical stimulation devices such as cochlear™ prostheses, organ assist or replacement devices, and other medical devices, have been successful in performing life saving and/or lifestyle enhancement functions for a number of individuals.
[0007] One category of such medical devices are hearing prostheses which include but are not limited to hearing aids and cochlear™ implant systems. Hearing aids are externally-worn devices which amplify sound to assist recipients who have degraded or impaired hearing due to, for example, age, injury or chronic ear or mastoid infections. Cochlear™ implant systems provide the benefit of hearing to individuals suffering from severe to profound hearing loss. Hearing loss in such individuals is due to the absence or destruction of the hair cells in the cochlea which transduce acoustic signals into nerve impulses. Cochlear™ implants essentially simulate the cochlear hair cells by directly delivering electrical stimulation to the auditory nerve fibers. This causes the brain to perceive a hearing sensation resembling the natural hearing sensation normally delivered to the auditory nerve.
[0008] Hearing prostheses usually involve the recipient having to wear various electronic components. The performance of such components, particularly those associated with the processing of audio sound, collectively and generally referred to as the audio path, can sometimes deteriorate in a very slow, almost undetectable fashion.
[0009] For example, hair and skin particles such as dandruff can settle near the port openings leading to the audio pickup devices such as microphones. These obstructing particles can adhere to the device due to the presence of natural body oils or other substances. Eventually accumulation of such particles may cause changes in the sound quality if left unchecked. There may be other reasons for gradual deterioration in the performance of the audio path, including those related to natural wear and tear as well as aging of of mechanical and electro-acoustic parts.
[0010] This gradual deterioration in performance is particularly problematic when the recipient of the hearing prosthesis is a child or infant. Such recipients are often unable to report changes in hearing prosthesis functionality, particularly if the gradual drop in performance is related to speech intelligibility. This in turn can impact on the child's speech development and their learning and communication abilities.
SUMMARY
[0011] In accordance with one aspect of the present invention, a method for detecting a change in the performance of an audio signal-processing path is disclosed. The method comprises: selecting a characteristic of a received audio signal indicative of its energy content; determining first and second predetermined values of the selected energy characteristic at respective first and second audio signal frequency bands; calculating a ratio of the first and second predetermined values for a reference time period and a test time period; and comparing the ratio at the reference time period with the ratio of the test time period to determine a performance change in the audio path.
[0012] In accordance with another aspect of the present invention, an apparatus for detecting a change in the performance of an audio signal processing path is disclosed. The apparatus comprises: means for determining first and second predetermined values of a selected characteristic at respective first and second frequency bands of a received audio signal, wherein the selected characteristic is indicative of the energy content of the audio signal; means for calculating a ratio of the first and second predetermined values for a reference time period and a test time period; and means for comparing the ratio at the reference time period with the ratio of the test time period to determine a performance change in the audio path.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is a simplified perspective view of internal and external components of an exemplary cochlear™ implant system shown in their operational position on a recipient, in accordance with one embodiment of the present invention.
[0014] FIGS. 2A-2C are perspective views of an external speech processing unit used in the cochlear™ implant system of FIG. 1 , in accordance with one embodiment of the present invention.
[0015] FIG. 3 is a functional block diagram of an audio signal processing path used in the cochlear™ implant system of FIG. 1 , in accordance with one embodiment of the present invention.
[0016] FIG. 4 is a perspective view of a conductive hearing aid, in accordance with one embodiment of the present invention.
DETAILED DESCRIPTION
[0017] Embodiments of the present invention are described below in connection with one embodiment of an exemplary hearing prosthesis, a cochlear™ prosthesis (also referred to as a cochlear™ implant system, cochlear™ prosthetic device and the like). cochlear™ implant systems use direct electrical stimulation of auditory nerve cells to bypass absent or defective hair cells that normally transducer acoustic vibrations into neural activity. Such devices generally use multi-contact electrodes inserted into the scala tympani of the cochlea so that the electrodes may differentially activate auditory neurons that normally encode differential pitches of sound. Such devices are also used to treat a smaller number of patients with bilateral degeneration of the auditory nerve. For such patients, a cochlear™ prosthetic device provides stimulation of the cochlear nucleus in the brainstem.
[0018] Exemplary cochlear™ prostheses in which the present invention may be implemented include, but are not limited to, those systems described in U.S. Pat. Nos. 4,532,930, 6,537,200, 6,565,503, 6,575,894 and 6,697,674, which are hereby incorporated by reference herein. FIG. 1 is a schematic diagram of an exemplary cochlear™ implant system 100 in which embodiments of the present invention may be implemented cochlear™ implant system 100 comprises external component assembly 142 which is directly or indirectly attached to the body of the recipient, and an internal component assembly 144 which is temporarily or permanently implanted in the recipient. External assembly 142 typically comprises audio pickup devices (not shown) for detecting sounds, a speech processing unit 116 that converts the detected sounds into a coded signal, a power source (not shown), and an external transmitter unit 106 . External transmitter unit 106 comprises an external coil 108 , and, preferably, a magnet 110 secured directly or indirectly to external coil 108 . Speech processor 116 processes the output of the audio pickup devices that may be positioned, for example, by the ear 122 of the recipient. Speech processor 116 generates a stimulation signals which are provided to external transmitter unit 106 via cable 118 .
[0019] Internal components 144 comprise an internal receiver unit 112 , a stimulator unit 126 , and an electrode array 134 . Internal receiver unit 112 comprises an internal receiver coil 124 and a magnet 140 fixed relative to internal coil 124 . Internal receiver unit 112 and stimulator unit 126 are hermetically sealed within a housing 128 . Internal coil 124 receives power and data from transmitter coil 108 . A cable 130 extends from stimulator unit 126 to cochlea 132 and terminates in an electrode array 134 . The received signals are applied by array 134 to the basilar membrane 136 thereby stimulating the auditory nerve 138 .
[0020] Collectively, transmitter antenna coil 108 (or more generally, external coil 108 ) and receiver antenna coil 124 (or, more generally internal coil 124 ) form an inductively-coupled coil system of a transcutaneous transfer apparatus 102 . Transmitter antenna coil 108 transmits electrical signals to the implantable receiver coil 124 via a radio frequency (RF) link 114 . Internal coil 124 is typically a wire antenna coil comprised of at least one and preferably multiple turns of electrically insulated single-strand or multi-strand platinum or gold wire. The electrical insulation of internal coil 124 is provided by a flexible silicone moulding (not shown). In use, implantable receiver unit 112 may be positioned in a recess of the temporal bone adjacent ear 122 of the recipient.
[0021] FIGS. 2A-2C are perspective views of an external speech processing unit 116 of cochlear™ implant system 100 , introduced above with reference to FIG. 1 . Speech processor unit 116 has, as noted, a behind-the-ear configuration. External speech processing unit 116 includes at least one directional microphone (not visible) having a front port 204 A and two rear ports 204 B and 204 C through which sound is received.
[0022] Speech processing unit 116 may experience a gradual, and at times undetectable, degradation of its ability to process sound due to the infiltration or accumulation of hair and skin particles in and through ports 204 . Also, liquid in the form of sweat or humidity may accumulate in speech processing unit 116 to slowly deteriorate components and/or component connections within the unit. Finally, the ability to process audio signals may also be compromised by component wear due to extended use.
[0023] This gradual deterioration in performance can be particularly problematic when the recipient of the hearing prosthesis is a child or infant. Such recipients are often unable to report changes in the functioning, particularly if the gradual drop in performance is related to speech intelligibility. This in turn can impact on the child's speech development and their learning and communication abilities. The present invention is directed to a system and method for diagnosing degradations in the components which are involved in the processing of the audio signals, referred to herein as the audio signal processing path or simply, audio path.
[0024] As noted, the components of a hearing prosthesis associated with the processing of audio sound are generally and collectively referred to herein as the audio path. FIG. 3 is a functional block diagram of one embodiment of an audio path 300 implemented in speech processor unit 116 . Audio path 300 comprises a microphone or other audio pickup device, analog front end 302 , a filter bank 304 , a sampling and selection stage 306 , a loudness growth function stage 308 and an RF encoder 310 . The output of audio path 300 is a stimulation signal 312 which is transmitted to implanted assembly 144 .
[0025] The audio pickup devices receive sound which is converted to an electrical signal 314 . Electrical signal 314 is sent to analog front end 302 , which is also known as an audio pre-processor. Generally, analog front end 302 amplifies electrical signal 314 received from microphone 301 . In particular, analog front end 302 amplifies the higher frequency components of electrical signal 314 to overcome the natural concentration of energy in the lower frequencies. The structure and operation of analog front end 302 is considered to be well-known to those of ordinary skill in the art and, therefore, is not described further herein.
[0026] If desired, the gain of analog front end 302 can be adjusted through an external sensitivity controller (not shown). Further, analog front end 302 may also include an automatic gain and sensitivity controller, the operation of which is well-known in the art.
[0027] Analog front end 302 generates an audio signal 316 which is received by filter bank 304 . Filter bank 304 comprises an array of band-pass filters (not shown) that process the input frequency range. As is well-known to those of ordinary skill in the art, the frequency bounds are based on critical bands, roughly linearly spaced below 1000 Hz and logarithmically spaced above 1000 Hz. It should be appreciated that other approaches now or later developed may also be utilized. Preferably, filter bank 304 is programmable since different speech coding strategies use different numbers of band-pass filters.
[0028] The output of each filter in filter bank 304 , commonly referred to as a filter bank channel 318 , is the envelope of the filtered audio signal 316 which is an estimate of the instantaneous power in the frequency range corresponding to the band of that filter. The structure and operation of filter bank 304 is considered to be well-known to those of ordinary skill in the art and, therefore, is not described further herein.
[0029] The output from each filter is then sampled at sampling & selection block 306 , and the total energy in each frequency band is determined. The structure and operation of sampling & selection block 306 is also considered to be well-known to those of ordinary skill in the art.
[0030] Thereafter, at block 308 the acoustic or electric stimulation levels are determined according to the recipient's exact response pattern requirement. The individual response pattern data, includes threshold and comfort levels for each electrode in electrode array 134 . This individual response data is stored in memory. The output signals from each channel 318 are digitized and modified by a microprocessor of loudness and growth function block 308 to reflect normal variations of hearing sensitivity with frequency. The structure and operation of loudness and growth function block 308 is considered to be well-known to those of ordinary skill in the art and, therefore, is not described further herein.
[0031] The output from some or all of these preset bands (depending on the strategy) is encoded at RF encoder block 310 , and transmitted by external coil 106 ( FIG. 1 ) to the internal components 144 of cochlear™ implant 100 .
[0032] As noted, audio path 300 can experience a gradual, and at times undetectable, degradation of its ability to process sound. The audio path diagnostic technique of the present invention detects changes in audio path performance. In particular, embodiments of the audio path diagnostic technique of the present invention detects gradual changes in performance which traditionally would not be detected until the cochlear™ implant system fails or undergoes some periodic maintenance.
[0033] The audio diagnostic technique of the present invention detects a change in audio path performance based on changes in a ratio of a selected characteristic indicative of the energy contained in selected high and low frequency bands of the audio signal. Degradation of audio path performance has been observed to manifest itself in a deterioration of the ability of the audio path to process higher frequency portions of the audio spectrum. Thus, the ratio of the energy contained in selected high- and low-frequency bands will change when such degradation of audio path performance occurs. Advantageously, such a ratio is not affected by changes in the energy content of the audio signals due to volume adjustments made by the recipient, since such adjustments affect the entire frequency range of the audio signal.
[0034] The selected energy characteristic (EC) may be any characteristic indicative of the energy content of the audio signal. For example, in one embodiment, the selected energy characteristic is the voltage of the audio signal, while in an alternative embodiment the selected energy characteristic is the current of the audio signal. In addition, the selected energy characteristic may represent the maximum energy, average energy, etc. of the audio signal. Accordingly, the measured EC value may be the mean, median, root mean square (RMS), maximum or other measured or calculated value of the selected energy characteristic.
[0035] In operation, the selected energy characteristic is obtained from filter bank 304 for, as noted, a selected high-frequency channel and a selected low-frequency channel. A ratio of the selected characteristic is then formed, such that
Q =( EC HF /EC LF ),
where,
EC HF =value of the energy characteristic at the selected high-frequency band; and EC LF =value of the selected energy characteristic at the selected low-frequency band.
[0039] As noted, audio path performance degradation is typically a gradual phenomenon. Thus, an immediate or short-term fall-off of performance cannot be relied upon as an indication of a degraded audio path. Rather, in accordance with one aspect of the invention, the change in the energy characteristic ratio, Q, is monitored. In one embodiment, a reference value, Q REF , for performance ratio Q is obtained once or periodically for comparison with a current value Q TEST , of performance ration Q. For example, the performance ratio Q may be periodically calculated over the course of a month, and then averaged or otherwise processed to derive a reference ratio value (Q REF ) which defines acceptable or normal audio path operations. The selected time intervals utilized to determine Q REF may be different for different hardware designs and settings.
[0040] The current performance ratio, Q TEST , may be a single measurement taken periodically. In one alternative embodiment, Q TEST is determined once during an immediately preceding short term period of time, for example, a single day. If more than one value is determined, the values are then averaged or otherwise numerically combined to obtain a single value, Q TEST , for comparison with Q REF .
[0041] A performance factor is then periodically calculated, using the formula:
K =( Q TEST /Q REF ),
where,
Q TEST =value of the performance ratio determined at a test time period; and Q REF =value of the performance ratio determined at a referenced time period.
The performance factor K is desirably calculated on a regular basis, for example, every 24 hours, although other suitable intervals could be used.
[0046] When the value of performance factor K is approximately one (1), then Q TEST is approximately equal to Q REF . However, as Q TEST diverges from Q REF over time, then such divergence is reflected in a change performance factor K. Such changes in performance factor K may be used to notify the recipient, and/or the carers, of a potential degradation of audio path performance. As one of ordinary skill in the art would appreciate, the degree of divergence which would be considered sufficient to generate such notification may vary according to the characteristics of the audio path. For example, in one embodiment, performance factor K must change by at least 10% for a period of three days for a notification to be broadcast.
[0047] As one of ordinary skill in the art would appreciate, any technique for notifying the recipient may be used. For example, a visible and/or audible alarm or indicator may be activated to notify the recipient that audio path 300 is not performing as desired. A person responsible for the operation of the prosthesis can then have cochlear™ implant 100 serviced to restore the specified performance levels.
[0048] The method of detecting a change in performance as described herein can alternatively be applied to the audio path of a conductive hearing aid. An example of such a hearing aid 400 is shown in FIG. 4 . Here, the implemented audio path may comprise, for example, the microphone that receives an acoustic input signal and converts it into an electrical signal, a filter which processes the signal; an amplifier which produces an amplified output signal therefrom; and an output converter.
[0049] It will be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the invention as shown in specific embodiments without departing from the spirit or scope of the invention as broadly described. For example, the audio path diagnostic techniques of the present invention have been presented in the context of hearing prosthesis such as cochlear™ implant system 100 and conductive hearing aid 400 . It should be appreciated that the audio path diagnostic techniques of the present invention can be applied to other devices implementing an audio signal processing path. As another example, the above embodiments are described in the context of a particular audio pickup device, a microphone. It should be appreciated, however, that the present invention can be used in connection with audio paths implementing other types of audio pickup devices now or later developed. Furthermore, such audio pickup devices may not be positioned in locations described above. As a further example, it should be appreciated that the teachings of the present invention can be used not only to determine degradation of an audio path but also the performance of an audio path when reconfigured. For example, the performance of the audio path implemented in cochlear™ implant system 100 above may be different if the type, size, quantity or location of the audio pickup device is changed. The audio path diagnostic techniques of the present invention can implemented to determine if such changes result in an increase or decrease in the performance of the implemented audio path. As a further example, in the above-embodiment the energy content of the high-frequency and low-frequency bands of the audio spectrum were determined and processed as described above. However, other cause of performance degradation may adversely affect certain frequency bands as compared with others. If detection of such causes are desired then the energy characteristic ratio may be obtained for other frequency bands rather then the high- and low-frequency bands noted above. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive. | In accordance with one aspect of the present invention, a method for detecting a change in the performance of an audio signal processing path is disclosed. The method comprises: selecting a characteristic of a received audio signal indicative of its energy content; determining first and second predetermined values of the selected energy characteristic at respective first and second audio signal frequency bands; calculating a ratio of the first and second predetermined values for a reference time period and a test time period; and comparing the ratio at the reference time period with the ratio of the test time period to determine a performance change in the audio path. | 7 |
FIELD OF THE INVENTION
[0001] The invention relates to a process for producing aminodiphenyl-amines, particularly 4-aminodiphenylamine (4-ADPA), by reacting nitrohalobenzenes with aromatic amines in the presence of a palladium catalyst and a base and subsequently hydrogenating the intermediate product thus obtained.
BACKGROUND OF THE INVENTION
[0002] 4-aminodiphenylamine (4-ADPA) is an important starting product for the synthesis of antioxidants and stabilizers in the rubber and polymer industry (Kirk-Othmer, Encyclopedia of Chemical Technology, 4 th Edition, 1992, Vol. 3, page 424-456; Ullmann's Encyclopedia of Industrial Chemistry, 5 th Edition, Vol. A3, 1985, pages 91-111).
[0003] 4-ADPA may be produced by various methods. One possible method of producing 4-ADPA is the two-stage reaction of aniline or aniline derivatives with p-nitrochlorobenzene in the presence of an acid acceptor or a neutralizing agent, optionally in the presence of a catalyst. Production by this method is described, for example, in DE-A 3,246,151, DE-A 3,501,698, DE-A 185663, U.S. Pat. Nos. 4,670,595, 4,187,249 and 4,187,248. The first stage is generally performed using copper catalysts, and the second stage is performed with different metal components, e.g. nickel (see for example U.S. Pat. No. 5,840,982). Reactions also of, for example, halogenated nitrobenzenes with amines in the presence of palladium catalysts are described in U.S. Pat. No. 5,576,460 and EP-A 846,676.
[0004] The disadvantage of the processes described in the above literature is frequently inadequate selectivity, in particular, during formation of the intermediate product, whereby yield losses occur as a result of more or less complex purification steps, before the 4-aminodiphenylamines may be formed by hydrogenation.
SUMMARY OF THE INVENTION
[0005] It was, therefore, desirable to provide a process for producing aminodiphenylamines, which starts from aromatic amines and, through reaction with appropriate nitrohalobenzenes and subsequent hydrogenation of the intermediate product formed, results in the desired aminodiphenylamines having good yield and elevated purity.
[0006] Therefore, the present invention provides a process for producing aminodiphenylamines by reacting nitrohalobenzenes with aromatic amines in the presence of a base and palladium catalyst and subsequently hydrogenating the product obtained with hydrogen.
DETAILED DESCRIPTION OF THE INVENTION
[0007] The nitrohalobenzenes used are preferably those in which the nitro group is in para-position relative to the halogen residue. Possible halogen residues are: fluorine, chlorine, bromine and iodine, preferably chlorine and bromine. The nitrohalobenzenes may also be substituted by one or more other residues, such as for example C 1 -C 4 alkyl residues. Naturally, the position of the nitro group relative to the halogen residues may also be other than the para-position, e.g. it may be in position 2 or 3.
[0008] Nitrohalobenzenes used in the present invention are: 4-nitro-2-methylchlorobenzene, 4-nitro-3-methylchlorobenzene, 4-nitrochloro-benzene, 3-nitrochlorobenzene and 2-nitrochlorobenzene. 4-nitrochloro-benzene is preferred.
[0009] Aromatic amines which may be used in the process according to the present invention are those aromatic amines which are known in relation to such a reaction, for example aniline, o-toluidine, m-toluidine, p-toluidine, 4-ethylaniline, 4-butylaniline, 4-isopropylaniline, 3,5-dimethyl-aniline or 2,4-dimethylaniline. Aniline is preferred. Naturally, the aromatic amines may also be used in the form of mixtures, in particular isomer mixtures.
[0010] In the process according to the invention, 1 to 10 mol, preferably 1.5 to 6 mol, and most preferably 2 to 4 mol of the aromatic amine, are generally used per mol of nitrohalobenzene.
[0011] According to the present invention, palladium catalysts, e.g. palladium/phosphine complexes, or other known palladium compounds or complexes may be used.
[0012] Suitable palladium/phosphine complex compounds are those in which the palladium has the valency 0 or II and suitable phosphine ligands are compounds such as triphenylphosphine, tri-o-toluylphosphine, tricyclohexylphosphine, tri-t-butylphosphine, bisdiphenylphosphine ethane, bisdiphenylphosphine propane, bis(diphenylphosphino)butane, bis(dicyclohexylphosphino)ethane, bis(diphenylphosphino)ferrocene, 5,5′-dichloro-6,6′-dimethoxybiphenyl-2,2′-diyl-bisdiphenylphosphine, bis-4,4′-dibenzofuran-3,3′-yl-bisdiphenylphosphine, 1,1′-bis(diphenylphosphino)diphenyl ether or bis(diphenylphosphino)binaphthyl, wherein the stated phenyl residues may be substituted by sulfonic acid residues and/or by one or more C 1 -C 12 alkyl groups or C 3 -C 10 cycloalkyl groups. In addition, polymer-bound phosphines may serve as ligands, e.g. tPP polymer (commercially available). Triphenylphosphine is preferably used as a ligand.
[0013] However, other palladium/phosphine complex compounds may also be used for the process according to the present invention, such as for example, nitrogen- or oxygen-containing ligands, such as 1,10-phenanthroline, diphenylethane diamine, [1,1′]-binaphthenyl-2,2′-diol (BINOL) and 1,1′-binaphthenyl-2,2′-dithiol (BINAS), or indeed those with two or more different heteroatoms, such as O, N, S.
[0014] Palladium compounds which may serve as catalysts include the following classes of compound, for example: palladium halides, acetates, carbonates, ketonates, nitrates, acetonates or palladacyclene, for example Pd 2 dba 3 , Pd(acac) 2 , Pd(OAc) 2 , PdCl 2 , (CH 3 CN) 2 Pd(NO 2 )Cl. Pd 2 dba 3 , Pd(acac) 2 , Pd(OAc) 2 , PdCl 2 are preferred. In addition, heterogeneous or immobilized palladium catalysts may also be used in the process according to the present invention, i.e. those which are applied to suitable inert supports, for example.
[0015] In the case of the palladium/phosphine complexes to be used according to the present invention, the molar ratio of the corresponding ligands to palladium is approximately 40:1: to 1:1, preferably 10:1 to 2:1, most preferably 8:1: to 4:1.
[0016] According to the present invention, the palladium catalysts, such as palladium/phosphine complexes and/or the other complexes or compounds which may be used, are generally used in amounts of from 0.0001 mol % to 10 mol %, preferably 0.001 mol % to 5 mol %, relative to the nitrohalobenzenes used.
[0017] Bases which may be used in the process according to the present invention are alkali and/or alkaline earth metal carbonates, alkoxides and/or hydroxides, in particular, potassium and/or sodium carbonate, cesium carbonate, sodium methanolate and barium hydroxide. Potassium and/or sodium carbonate are preferably used. The bases may be used in a substoichiometric amount or in an excess of up to ten times the equivalent amount relative to the nitrohalobenzene. The bases are preferably used in a 0.3 to 2 times equivalent amount, relative to nitrohalobenzene.
[0018] It is advantageous for the process according to the present invention for the bases used to be pretreated by grinding and/or drying.
[0019] In the process according to the invention, grinding may be performed in commercially available mills. Grinding affects a drastic increase in specific surface area, which results in a clear increase in conversion. In many cases, grinding may increase the specific surface area by a factor of 10 to 20.
[0020] After grinding, the specific areas of the bases are approx. 0.1 to 10 m 2 /g, preferably 0.2 to 1 m 2 /g (BET).
[0021] As a result of the pronounced hygroscopic properties of the bases used in the process according to the present invention, the latter have a tendency towards the more or less marked absorption of atmospheric constituents, such as water or carbon dioxide. From a level of absorption of atmospheric constituents of approx. 30 weight percent, a marked influence on achievable conversion levels may be noted. Therefore, in addition to grinding, drying of the bases is also frequently indicated.
[0022] Drying of the bases proceeds, for example, in that they are heated under a reduced pressure of approx. 0.01 to 100 mbar for several hours to temperatures of approx. 50 to 200° C., preferably 100 to 160° C.
[0023] The first stage of the process according to the present invention may be performed at temperatures in the range of from 20 to 250° C., preferably at temperatures of from 120 to 180° C. The reaction temperatures depend, in particular, on the type of starting products, the catalyst and the bases used.
[0024] The process according to the present invention may be performed both in the presence and in the absence of a suitable solvent. Examples of possible solvents are inert organic hydrocarbons, such as xylene and toluene. In addition, the aromatic amines used may themselves function as solvents.
[0025] In the process according to the present invention, the reaction water arising may, if desired (as in DE-A 26 33 811 and DE-A 32 46 151), be removed, for example, by distillation with the aid of a suitable entraining agent.
[0026] The amount of solvent used may be readily determined by appropriate preliminary tests.
[0027] The process according to the present invention may be performed continuously or discontinuously by conventional methods.
[0028] In the process according to the present invention, the reaction product obtained after reaction of the aromatic amines with the halonitroaromatics is hydrogenated with hydrogen, wherein hydrogenation may be performed in the presence of the palladium catalyst already present, optionally with the addition of a suitable inert catalyst support.
[0029] It is also possible to perform hydrogenation in the presence of additional hydrogenation catalysts, such as those on a nickel, palladium or platinum basis, optionally using a suitable catalyst support.
[0030] Suitable materials for use as catalyst support are all industrially conventional catalyst supports based on carbon, elemental oxides, elemental carbides or elemental salts in various forms. Examples of carbon-containing supports are coke, graphite, carbon black or activated carbons. Examples of elemental oxide catalyst supports are SiO 2 (natural or synthetic silicic acid, quartz), Al 2 O 3 (α, γ-Al 2 O 3 ), aluminas, natural or synthetic aluminosilicates (zeolites), phyllosilicates such as bentonite and montmorillonite, TiO 2 (rutile, anatase), ZrO 2 , MgO or ZnO. Examples of elemental carbides and salts are SiC, AlPO 4 , BaSo 4 , CaCO 3 . In principle, both synthetic materials and supports from natural sources, such as pumice stone, kaolin, bleaching earths, bauxites, bentonites, diatomaceous earth, asbestos or zeolites, may be used.
[0031] Further supports which may be used for the catalysts usable according to the present invention are elemental mixed oxides and hydrogenated oxides of elements of the groups 2 to 16 of the periodic table together with rare-earth metals (atomic numbers 58 to 71), preferably from the elements Al, Si, Ti, Zr, Zn, Mg, Ca, Sn, Nb and Ce, which may inter alia be produced by means of mechanical mixing, joint precipitation of salts or via cogels of salts and/or alkoxides, as known to the person skilled in the art.
[0032] The supports may be used both as chemically uniform pure substances and as mixtures. Materials in both lump and powder form are suited for use according to the present invention as catalyst supports. Where the supported catalyst is arranged as a fixed bed, the support is preferably used in the form of molded articles, e.g. balls, cylinders, rods, hollow cylinders or rings. Catalyst supports may optionally be further modified by extrusion, tabletting, optionally with the admixture of further catalyst supports or binders, such as SiO 2 or Al 2 O 3 , and calcining. The inner surface area of the support (BET surface area) is 1 to 2000 m 2 /g, preferably 10 to 1600 m 2 /g, most preferably 20 to 1500 m 2 /g. Preparation and further processing are well known to the person skilled in the art and are known in the prior art.
[0033] Activated carbons and Si-, Al-, Mg-, Zr- and Ti-containing materials are preferably used as support materials. Activated carbon is most preferred.
[0034] The above-mentioned supports may also be loaded with palladium with a metal content of from 0.01 to 50 wt. %, preferably 0.1 to 10 wt. %, relative to the total weight of the catalyst.
[0035] The above-mentioned support materials or the support materials loaded with palladium may be used in amounts of from 0.01 to 20 wt. %, relative to the halonitrobenzene used, preferably in amounts of from 0.01 to 10 wt. %. The use of activated carbon loaded with palladium is preferred.
[0036] Hydrogenation may also be performed using other reduction methods, as are known to the person skilled in the art and listed, for example, in “Reductions in Organic Chemistry, Second Edition, ACS Monograph 188”.
[0037] The hydrogenation temperatures range from to approx. 0 to 200° C., particularly 40 to 150° C.; the pressures (hydrogen pressure) are around 0.1 to 150 bar, particularly 0.5 to 70 bar, most preferably 1 to 50 bar.
[0038] Using the process according to the present invention, corresponding 4-aminodiphenylamines are obtained with high selectivities (>98%) and in yields of up to 99%.
EXAMPLES
Example 1
[0039] 372.0 g (4.00 mol) of aniline, 0.25 g (0.00082 mol) of palladium acetonylacetonate and 0.86 g (0.00328 mol) of triphenylphosphine are initially introduced into a multi-necked, round-bottomed flask in an inert atmosphere and stirred for 10 minutes at room temperature. 157.6 g (1.00 mol) of 4-chloronitrobenzene are added and stirring is performed for a further 10 minutes at room temperature. Then, 120.0 g (0.87 mol) of ground potassium carbonate and 40 ml of xylene are added. Refluxing with water separation is performed with vigorous stirring for 45 mins. Gas-chromatographic monitoring shows complete conversion of para-chloronitrobenzene.
[0040] The mixture is allowed to cool to 85° C. and diluted with 300 ml of water. The organic phase is hydrogenated with 1.0 g Pd/C (5% Pd/C) for 15 mins at 10 bar of hydrogen pressure, wherein the temperature reaches 110° C.
[0041] After filtration and distillation, 182 g (99% of theoretical) of 4-aminodiphenylamine are obtained.
Example 2
[0042] 372.0 g (4.00 mol) of aniline, 0.20 g (0.00066 mol) of palladium acetonylacetonate and 0.69 g (0.00263 mol) of triphenylphosphine are initially introduced into a multi-necked, round-bottomed flask in an inert atmosphere and stirred for 10 minutes at room temperature. 157.6 g (1.00 mol) of 4-chloronitrobenzene are added and stirring is performed for a further 10 minutes at room temperature. Then, 120.0 g (0.87 mol) of ground potassium carbonate and 40 ml of xylene are added. Refluxing with water separation is performed with vigorous stirring for 45 mins. Gas-chromatographic monitoring shows complete conversion of para-chloronitrobenzene.
[0043] The mixture is allowed to cool to 85° C. and diluted with 300 ml of water. The organic phase is hydrogenated with 1.0 g Pd/C (3% Pd/C) for 11 mins at 10 bar of hydrogen pressure, wherein the temperature reaches 120° C.
[0044] After filtration and distillation, 181 g (98% of theoretical) of 4-aminodiphenylamine are obtained.
Example 3
[0045] 372.0 g (4.00 mol) of aniline, 0.25 g (0.00082 mol) of palladium acetonylacetonate and 0.86 g (0.00328 mol) of triphenylphosphine are initially introduced into a multi-necked, round-bottomed flask in an inert atmosphere and stirred for 10 minutes at room temperature. 157.6 g (1.00 mol) of 4-chloronitrobenzene are added and stirring is performed for a further 10 minutes at room temperature. Then, 96.6 g (0.70 mol) of ground potassium carbonate and 50 ml of xylene are added. Refluxing with water separation is performed with vigorous stirring for 45 mins. Gas-chromatographic monitoring shows complete conversion of para-chloronitrobenzene.
[0046] The mixture is allowed to cool to 85° C. and diluted with 300 ml of water. The organic phase is hydrogenated with 1.0 g Pd/C (5% Pd/C loading) for 14 mins at 10 bar of hydrogen pressure, wherein the temperature reaches 120° C.
[0047] After gas-chromatographic investigation, 99% of 4-aminodiphenyl-amine is obtained.
Example 4
[0048] 372.0 g (4.00 mol) of aniline, 0.22 g (0.00098 mol) of palladium acetate and 1.04 g (0.00397 mol) of triphenylphosphine are initially introduced into a multi-necked, round-bottomed flask in an inert atmosphere and stirred for 10 minutes at room temperature. 157.6 g (1.00 mol) of 4-chloronitrobenzene are added and stirring is performed for a further 10 minutes at room temperature. Then, 96.6 g (0.70 mol) of ground potassium carbonate and 50 ml of xylene are added. Refluxing with water separation is performed with vigorous stirring for 45 mins. Gas-chromatographic monitoring shows complete conversion of para-chloronitrobenzene.
[0049] The organic phase is hydrogenated for 25 mins at 10 bar of hydrogen pressure, wherein the temperature reaches 140° C. After gas-chromatographic investigation, 98% of 4-aminodiphenylamine is obtained.
Example 5
[0050] 372.0 g (4.00 mol) of aniline, 0.30 g (0.00098 mol) of palladium acetonylacetonate and 1.04 g (0.00397 mol) of triphenylphosphine are initially introduced into a multi-necked, round-bottomed flask in an inert atmosphere and stirred for 10 minutes at room temperature. 157.6 g (1.00 mol) of 4-chloronitrobenzene are added and stirring is performed for a further 10 minutes at room temperature. Then, 96.6 g (0.70 mol) of ground potassium carbonate and 50 ml of xylene are added. Refluxing with water separation is performed with vigorous stirring for 45 mins. Gas-chromatographic monitoring shows complete conversion of para-chloronitrobenzene.
[0051] The mixture is allowed to cool to 85° C. and diluted with 300 ml of water. The organic phase is hydrogenated for 34 mins at 10 bar of hydrogen pressure, wherein the temperature reaches 140° C.
[0052] After gas-chromatographic investigation, 99% of 4-aminodiphenylamine is obtained.
Example 6
[0053] 372.0 g (4.00 mol) of aniline, 0.30 g (0.00098 mol) of palladium acetonylacetonate and 1.04 g (0.00397 mol) of triphenylphosphine are initially introduced into a multi-necked, round-bottomed flask in an inert atmosphere and stirred for 10 minutes at room temperature. 157.6 g (1.00 mol) of 4-chloronitrobenzene are added and stirring is performed for a further 10 minutes at room temperature. Then, 96.6 g (0.70 mol) of ground potassium carbonate and 50 ml of xylene are added. Refluxing with water separation is performed with vigorous stirring for 45 mins. Gas-chromatographic monitoring shows complete conversion of para-chloronitrobenzene.
[0054] The mixture is allowed to cool to 85° C. and diluted with 300 ml of water. The organic phase is hydrogenated after the addition of 2.0 g activated carbon for 24 mins at 10 bar of hydrogen pressure, wherein the temperature reaches 140° C.
[0055] After gas-chromatographic investigation, 99% of 4-ADPA is obtained.
Example 7
[0056] Pretreatment of Bases:
[0057] Commercially available potassium carbonate is ground, for example, for approx. 5 minutes in a kitchen or ball mill. The potassium carbonate made by Grüssing and treated in this way thereby experiences an increase in specific surface area from 0.04 m 2 /g to 0.52 m 2 /g and exhibits a primary crystallite size of 10 μm or less. The ground potassium carbonate is then dried for 5 hours at a pressure of 1 mbar and a temperature of 150° C. If other bases are used, these are pretreated in a similar manner.
[0058] Although the invention has been described in detail in the foregoing for the purpose of illustration, it is to be understood that such detail is solely for that purpose and that variations can be made therein by those skilled in the art without departing from the spirit and scope of the invention except as it may be limited by the claims. | The present invention relates to the production of aminodiphenyl-amines resulting in good yields and high purity levels when aromatic amines are reacted with nitrohalobenzenes in the presence of a palladium catalyst and a base and the product thus obtained is subsequently hydrogenated with hydrogen. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a divisional of application Ser. No. 10/338,530, filed Jan. 8, 2003, pending, which is a divisional of application Ser. No. 09/819,472, filed Mar. 28, 2001, now U.S. Pat. No. 6,545,498, issued Apr. 8, 2003, which is a divisional of application Ser. No. 09/166,369, filed Oct. 5, 1998, now U.S. Pat. No. 6,329,832, issued Dec. 11, 2001.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates in general to semiconductor manufacturing and, more specifically, to in-line testing of flip-chip semiconductor assemblies.
2. State of the Art
As shown in FIG. 1 , in a conventional process 10 for manufacturing flip-chip semiconductor assemblies, singulated dice are flip-chip attached with a conductive epoxy or solder to a printed circuit board (PCB) or other substrate to form a flip-chip semiconductor assembly. Once the dice are attached by curing of the epoxy or reflow of the solder, the dice are then encapsulated, underfilled, or both, using a nonconductive epoxy or other encapsulation material. The electrical characteristics of the flip-chip semiconductor assembly are then tested and, if the assembly passes the test, it is selected for shipping to customers.
If the flip-chip semiconductor assembly does not pass the test, then it proceeds to a repair station, where it is repaired using one or more “known-good dice” (KGD) 12 (i.e., dice that have already passed all standard electrical tests and have been through burn-in). Specifically, those dice in the assembly that are believed to have caused the assembly to fail the test are electrically disconnected from the rest of the assembly, typically using laser fuses. One or more KGD are then attached to the PCB of the assembly to replace the disconnected dice. Once the KGD are attached, the assembly is retested and, if it passes, it too is selected for shipping to customers.
The conventional KGD repair process described above generally works well to repair flip-chip semiconductor assemblies, but the process necessary to produce KGD can be an expensive one. Also, the described KGD repair process does not test for, or repair, problems with the interconnections between the dice and the PCB in a flip-chip semiconductor assembly. Rather, it only repairs problems with non-functioning dice or defective solder bumps. Finally, the KGD in the described repair process end up going through burn-in twice: a first time so they can be categorized as a KGD, and a second time when the flip-chip semiconductor assembly to which they are attached goes through burn-in. This is obviously a waste of burn-in resources and also stresses the KGD far beyond that necessary to weed out infant mortalities.
Therefore, there is a need in the art for a method of testing flip-chip semiconductor assemblies that reduces or eliminates the need for the KGD repair process described above.
BRIEF SUMMARY OF THE INVENTION
In a method for electrically testing a flip-chip semiconductor assembly in accordance with this invention, the assembly is tested using, for example, an in-line or in-situ test socket or probes after one or more integrated circuit (IC) dice and a substrate, such as a printed circuit board (PCB), are brought together to form the assembly and before the IC dice are encapsulated or otherwise sealed for permanent operation. As a result, any problems with the IC dice or their interconnection to the substrate can be fixed before sealing of the dice complicates repairs. The method thus avoids the problems associated with conventional known-good-die (KGD) repairs. Also, speed grading can be performed while the dice are tested.
The assembly may be manufactured using a “wet” conductive epoxy, such as a heat-snap-curable, moisture-curable, or radiation-curable epoxy, in which case bond pads on the IC dice can be brought into contact with conductive bumps on the substrate formed of the epoxy for the testing, which can then be followed by curing of the epoxy to form permanent die-to-substrate interconnects if the assembly passes the test. If the assembly does not pass the test, the lack of curing allows for easy repair. After curing but before sealing of the IC dice, the assembly can be tested again to detect any interconnection problems between the IC dice and the substrate.
The assembly may also be manufactured using a “dry” conductive epoxy, such as a thermoplastic epoxy, for conductive die-attach, in which case the IC dice and the substrate can be brought together and the epoxy cured to form permanent die-to-substrate interconnections, after which the testing may take place. Since the testing occurs before sealing of the IC dice, repair is still relatively easy.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
FIG. 1 is a flow chart illustrating a conventional repair method for flip-chip semiconductor assemblies using known-good dice (KGD);
FIG. 2 is a flow chart illustrating a method for in-line testing of flip-chip semiconductor assemblies in accordance with this invention;
FIG. 3 is an isometric view of a flip-chip semiconductor assembly and in-line test socket or probes implementing the method of FIG. 2 ;
FIG. 4 is a flow chart illustrating a method for in situ testing of flip-chip semiconductor assemblies in accordance with this invention; and
FIG. 5 is an isometric view of a flip-chip semiconductor assembly and in situ test socket implementing the method of FIG. 4 .
DETAILED DESCRIPTION OF THE INVENTION
As shown in FIGS. 2 and 3 , in a process 20 for manufacturing flip-chip semiconductor assemblies in accordance with this invention, a printed circuit board (PCB) 22 is indexed into a die attach station (not shown), where it is inserted into an in-line test socket 24 or contacted by probes 25 . It will be understood by those having skill in the technical field of this invention that the invention is applicable not only to PCBs, but also to a wide variety of other substrates used in the manufacture of flip-chip semiconductor assemblies.
When conductive epoxy dots 26 or “pads” deposited on the PCB 22 at the die ends of die-to-board-edge conductive traces 30 are made from a “wet” epoxy (i.e., a quick-cure epoxy such as a heat-snap-curable, radiation-curable, or moisture-curable epoxy), then integrated circuit (IC) dice 28 are pressed (active surfaces down) against the dots 26 during flip-chip attach so electrical connections are formed between the dice 28 and the in-line test socket 24 or probes 25 through the dots 26 and conductive traces 30 on the PCB 22 . Of course, it will be understood that the invention is also applicable to other flip-chip die-attach methods including, for example, solder-based methods. It will also be understood that the dice 28 may be of any type, including, for example, Dynamic Random Access Memory (DRAM) dice, Static RAM (SRAM) dice, Synchronous DRAM (SDRAM) dice, microprocessor dice, Application-Specific Integrated Circuit (ASIC) dice, and Digital-Signal Processor (DSP) dice.
Once such electrical connections are formed, an electrical test is performed on the flip-chip semiconductor assembly 32 formed by the dice 28 and the PCB 22 using the in-line test socket 24 or probes 25 . This test typically involves checking for open connections that should be closed, and vice versa, but it can also involve more, fewer, or different electrical tests as need dictates. For example, the testing may also include speed grading the dice 28 for subsequent speed sorting. Also, the testing typically occurs while the PCB 22 is singulated from its carrier (not shown).
If the assembly 32 fails the test, it is diverted to a rework station, where any dice 28 identified as being internally defective or as having a defective interconnection with the PCB 22 can easily be removed and reworked, either by repairing the failing dice 28 themselves or by repairing conductive bumps (not shown) on the bottom surfaces of the dice 28 used to connect the dice 28 to the conductive epoxy dots 26 on the PCB 22 . Once repaired, the assembly 32 returns for retesting and, if it passes, it is advanced in the process 20 for quick curing along with all assemblies 32 that passed the test the first time through.
During quick cure, the “wet” epoxy dots 26 of the assembly 32 are cured, typically using heat, radiation, or moisture. The assembly 32 is then electrically tested again to ensure that the quick curing has not disrupted the interconnections between the dice 28 and the conductive traces 30 through the conductive epoxy dots 26 and the bumps (not shown) on the bottom surfaces of the dice 28 . If quick curing has disrupted these interconnections, then the assembly 32 proceeds to the rework station, where the connections between the bumps and the dots 26 can be repaired. The repaired assembly 32 is then retested and, if it passes, it proceeds to encapsulation (or some other form of sealing) and, ultimately, is shipped to customers along with those assemblies 32 that passed this testing step the first time through. Of course, it should be understood that this invention may be implemented with only one test stage for “wet” epoxy assemblies, although two stages are preferable.
When the conductive epoxy dots 26 are made from a “dry” epoxy (e.g., a thermoplastic epoxy), then the PCB 22 is indexed and inserted into the in-line test socket 24 or connected to the probes 25 as described above, but the dice 28 are attached to the PCB 22 using heat before the assembly 32 proceeds to testing. Testing typically takes place while the PCB 22 is singulated from its carrier (not shown).
During testing, if the assembly 32 fails, then it proceeds to a rework station, where the bumps on the bottom of the dice 28 , the dice 28 themselves, or the interconnection between the bumps and the conductive epoxy dots 26 can be repaired. The repaired assembly 32 then proceeds to encapsulation (or some other form of sealing) and, eventually, is shipped to customers along with those assemblies 32 that passed the testing the first time through.
Thus, this invention provides a repair method for flip-chip semiconductor assemblies that is less expensive than the previously described known-good-die (KGD) based rework process, because it does not require the pretesting of dice that the KGD process requires. Also, the methods of this invention are applicable to testing for both internal die defects and die-to-PCB interconnection defects, and to repairing interconnections between dice and a PCB in a flip-chip semiconductor assembly, whereas the conventional KGD process is not. In addition, these inventive methods do not waste bum-in resources, in contrast to the conventional KGD process previously described. Finally, this invention allows for early and convenient speed grading of flip-chip semiconductor assemblies.
As shown in FIGS. 4 and 5 , in a process 40 for manufacturing flip-chip semiconductor assemblies in accordance with this invention, a printed circuit board (PCB) 42 is indexed into a die attach station (not shown), where it is inserted into an in situ test socket 44 . It will be understood by those having skill in the technical field of this invention that the invention is applicable not only to PCBs but also to a wide variety of other substrates used in the manufacture of flip-chip semiconductor assemblies.
When conductive epoxy dots 46 or “pads” deposited on the PCB 42 at the die ends of die-to-board-edge conductive traces 50 are made from a “wet” epoxy (i.e., a quick-cure epoxy such as a heat-snap-curable, radiation-curable, or moisture-curable epoxy), then integrated circuit (IC) dice 48 are pressed (active surfaces down) against the dots 46 during flip-chip attach so electrical connections are formed between the dice 48 and the in situ test socket 44 through the dots 46 and conductive traces 50 on the PCB 42 . Of course, it will be understood that the invention is also applicable to other flip-chip die-attach methods including, for example, solder-based methods. It will also be understood that the dice 48 may be of any type, including, for example, Dynamic Random Access Memory (DRAM) dice, Static RAM (SRAM) dice, Synchronous DRAM (SDRAM) dice, microprocessor dice, Application-Specific Integrated Circuit (ASIC) dice, and Digital Signal Processor (DSP) dice.
Once such electrical connections are formed, an electrical test is performed on the flip-chip semiconductor assembly 52 formed by the dice 48 and the PCB 42 using the in situ test socket 44 . This test typically involves checking for open connections that should be closed, and vice versa, but it can also involve more, fewer, or different electrical tests as need dictates. If the assembly 52 fails the test, it is diverted to a rework station, where any dice 48 identified as being internally defective or as having a defective interconnection with the PCB 42 can easily be removed and reworked, either by repairing the failing dice 48 themselves or by repairing conductive bumps (not shown) on the bottom surfaces of the dice 48 used to connect the dice 48 to the conductive epoxy dots 46 on the PCB 42 . Once repaired, the assembly 52 returns for retesting and, if it passes, it is advanced in the process 40 for quick curing along with all assemblies 52 that passed the test the first time through.
During quick cure, the “wet” epoxy dots 46 of the assembly 52 are cured, typically using heat, radiation, or moisture. The assembly 52 is then electrically tested again to ensure that the quick curing has not disrupted the interconnections between the dice 48 and the conductive traces 50 through the conductive epoxy dots 46 and the bumps (not shown) on the bottom surfaces of the dice 48 . If quick curing has disrupted these interconnections, then the assembly 52 proceeds to another rework station, where the connections between the bumps and the dots 46 can be repaired. The repaired assembly 52 is then retested and, if it passes, it proceeds to encapsulation (or some other form of sealing) and, ultimately, is shipped to customers along with those assemblies 52 that passed this testing step the first time through. Of course, it should be understood that this invention may be implemented with only one test stage for “wet” epoxy assemblies, although the two stages shown in FIG. 4 are preferable.
When the conductive epoxy dots 46 are made from a “dry” epoxy (e.g., a thermoplastic epoxy), then the PCB 42 is indexed and inserted into the in situ test socket 44 as described above, but the dice 48 are attached to the PCB 42 using heat before the assembly 52 proceeds to testing. During testing, if the assembly 52 fails, then it proceeds to a rework station, where the bumps on the bottom of the dice 48 , the dice 48 themselves, or the interconnection between the bumps and the conductive epoxy dots 46 can be repaired. The repaired assembly 52 then proceeds to encapsulation (or some other form of sealing) and, eventually, is shipped to customers along with those assemblies 52 that passed the testing the first time through.
Thus, this invention provides a repair method for flip-chip semiconductor assemblies that is less expensive than the previously described known-good-die (KGD) based rework process, because it does not require the pretesting of dice that the KGD process requires. Also, the methods of this invention are applicable to testing for both internal die defects and die-to-PCB interconnection defects, and to repairing interconnections between dice and a PCB in a flip-chip semiconductor assembly, whereas the conventional KGD process is not. In addition, these inventive methods do not waste burn-in resources, in contrast to the conventional KGD process previously described.
Although this invention has been described with reference to particular embodiments, the invention is not limited to these described embodiments. Rather, the invention is limited only by the appended claims, which include within their scope all equivalent methods that operate according to the principles of the invention as described herein. | Flip-chip semiconductor assemblies, each including integrated circuit (IC) dice and an associated substrate, are electrically tested before encapsulation using an in-line or in-situ test socket or probes at a die-attach station. Those assemblies using “wet” quick-cure epoxies for die attachment may be tested prior to the epoxy being cured by pressing the integrated circuit (IC) dice against interconnection points on the substrate for electrical connection, while those assemblies using “dry” epoxies may be cured prior to testing. In either case, any failures in the dice or in the interconnections between the dice and the substrates can be easily fixed, and the need for the use of known-good-die (KGD) rework procedures during repair is eliminated. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims priority from Korean Patent Application Nos. 35735/2003, filed Jun. 3, 2003 and 55048/2003, filed Aug. 8, 2003, the entire contents of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a mobile terminal, and in particular to a garbage collection system and method for deleting not needed files stored in the active memory of a mobile communication terminal.
2. Description of Related Art
With the development of mobile communication techniques and terminal fabrication techniques, an individual can use a mobile terminal to watch moving pictures, listen to music, connect to the Internet and play mobile games. In order to make a mobile terminal perform the above various functions, a high capacity flash memory is essential. To play moving pictures and music, the terminal needs to have the capacity to store large volumes of data. To maintain a sufficiently free data storage space, not needed or garbage data such as unused programs, read word-messages, and music or image files to which a user will not listen/watch need to be deleted, before new data can be stored. This can be performed by a write/delete function applied to the flash memory areas that contain the unnecessary or unwanted data (hereafter “garbage”).
In a general flash memory, data is stored by recording a byte unit or a word unit. However, data can be deleted only by deleting a designated sector in each storage device. Accordingly, in an EFS (embedded file system), in order to use characteristics of the flash memory, a region is divided/managed into blocks having a certain size, and each block has a header so as to indicate the nature of the recorded contents.
When contents of the block are changed, the block is processed as garbage, a free block is reallocated, and changed contents are recorded again. When garbage generated in deleting or changing of data is increased, the size of a usable free block is reduced. When garbage exceeds a predetermined amount, the terminal deletes the garbage automatically. This is called “garbage collection.”
In a general garbage collection method, there are two approaches, one is performing garbage collection automatically when garbage exceeding a designated reference percentage of one sector is generated, and the other is performing garbage collection forcibly according to a request from a file system when there is data to be stored and there is an insufficient number of free blocks.
Unfortunately, in performing garbage collection for lack of a storage space or when garbage exceeds a reference level, the terminal may reset or the terminal operation speed may be diminished, if system resources are utilized beyond their limits.
In addition, if garbage is unnecessarily collected too frequently, the memory processing speed may be diminished, and the life span of the memory may be adversely affected.
SUMMARY OF THE INVENTION
A garbage collection method for a mobile terminal comprises setting at least a garbage collection condition for the mobile terminal; converting a state of the mobile terminal from a first state to a second state when the at least one garbage collection condition is met; and starting a garbage collection procedure while the mobile terminal is in the first state, wherein in the first state the garbage collection procedure is not interrupted by an external event.
The method may further comprise notifying a user when garbage collection procedure starts, and notifying a user when garbage collection procedure is completed. The state of the mobile terminal is reverted from the second state back to the first state when the garbage collection procedure is completed. The first state represents an idle state for the mobile terminal. The second state represents a safe mode for the mobile terminal. In an idle state the mobile terminal can but is not performing any telephony events. In the safe mode the mobile terminal cannot perform any telephony events.
At least one garbage collection condition is met when the mobile terminal is in an idle state. At least one garbage collection condition is met when the mobile terminal comprises a clam-shell design having a flip portion, and wherein the flip portion is closed, for example. At least one garbage collection condition is met when level of garbage collected exceeds a first threshold. At least one garbage collection condition is met by way of a user interacting with the mobile terminal. The user may interact with the mobile terminal by way of at least one of a touch display, a microphone, and a keypad.
In one embodiment, a user is notified of progress of the garbage collection procedure by way of at least one of a visual alert, a voice alert, and a tactile alert. A telephony event comprises at least one of communicating a message, receiving a voice call, and making a voice call. In one embodiment, the garbage collection procedure is stopped when a telephony event occurs.
A method of managing storage space in a mobile communication device, wherein the storage space is utilized to store telephony event related data is provided. The method comprises monitoring the mobile communication device to detect an idle state, wherein no telephony events are pending; switching the mobile communication device to a safe mode, wherein no telephony event may be performed by the mobile communication terminal; and removing unwanted data from the storage space while the mobile communication device is in the safe mode.
The removing step is terminated when at least a telephony event is received by the mobile communication device. The switching step is performed when a first condition is met. The first condition is met according to a command input to the mobile communication terminal to manage the storage space. Alternatively, the first condition is met when the free space in the storage space has reached a minimum threshold.
A mobile communication terminal, in accordance with another embodiment, comprises a user interface module for controlling user interface features of the mobile communication terminal; a file system module for controlling garbage management of data stored in mobile communication terminal's storage space; and a mode control module for switching the mobile communication terminal from a first mode to a second mode, when at least one condition is met.
The first mode is an idle mode. The second mode is a safe mode. The file system module removes garbage from the mobile communication's storage space, when the mode control module switches the mobile communication terminal from the first mode to the second mode.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings are included to provide a further understanding of the invention. They 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.
FIG. 1 is a block diagram illustrating a garbage collection method for a mobile terminal in accordance with one embodiment of the invention; and
FIG. 2 is a flow chart illustrating a garbage collection method for a mobile terminal in accordance with one embodiment of the present invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Referring to FIG. 1 , a UI (user interface) module 100 is provided for setting garbage collection conditions and notifying the user of when garbage collection starts and ends. An FS (file system) module 200 is provided for generating garbage, checking whether the garbage collection conditions are satisfied, and performing garbage collection. An MC (micro-control) module 300 is provided for converting the mobile terminal into a safe mode and performing of garbage collection.
The UI, FS and MC modules may be implemented in the form of hardware, software or a combination thereof. The UI_module 100 controls operations of a display unit 10 , a speaker unit 20 , a voice input unit 30 and a key input unit 40 , for example. Garbage collection conditions of the UI_module 100 may be set by the user through key inputs.
For example, a user may select to perform the garbage collection procedure when a flip part of the mobile terminal is closed (i.e., when the mobile terminal is in an idle state) or when garbage size is greater than a threshold. The FS_module 200 notifies the UI_module 100 of the time when garbage collection starts or ends. The UI_module 100 notifies the user of garbage collection times, and accordingly the user is alerted that garbage collection is in progress.
To notify the user of start and end of the garbage collection, various methods such as displaying a character or an icon on the display unit of the mobile terminal or generating a sound through the speaker unit, or vibrating the mobile terminal may be implemented. The user can set up and change the above methods, depending on implementation.
In one embodiment, the FS_module 200 controls operation of the memory unit 50 . When conditions set up by the user are satisfied, the UI_module 100 requests the MC_module 300 to convert the terminal from an idle_state into a safe mode. When the MC_module 300 converts the terminal into the safe mode, the garbage collection is performed.
When the user sets up conditions to perform the garbage collection and when the terminal folder is closed, for example, the FS_module 200 determines if the conditions are satisfied by sensing opening/closing of the folder or determining when the mobile terminal is idle. The user may set up conditions to perform garbage collection when garbage is greater than a certain percent of a memory capacity. In that case, the FS_module 200 determines if conditions are satisfied by checking the memory use rate.
In addition, when the conditions are satisfied and the garbage collection is performed, the FS_module 200 notifies the UI_module 100 and the MC-module 300 of the garbage collection process starting or ending. The MC_module 300 controls operations of the control unit 60 . When the garbage collection process starts, FS_module 200 switches the state of the terminal from idle state to safe mode and notifies the FS_module 200 of the mode conversion, and accordingly garbage collection is performed.
Idle state refers to a condition in which the mobile terminal is not performing any telephony events, even though it can. That is, idle state represents an instance when mobile terminal is not communicating with another system or is not in the process of making or receiving a call. In the safe mode, however, the mobile device cannot perform any telephony events. The safe mode means that a message cannot be received and conversation by telephone cannot be performed. Safe mode is set in order to prevent external interruptions during the garbage collection process.
In one embodiment, because the user may have an important telephone call or message while the garbage collection is performed, in conversion of the mobile terminal into the safe mode, it may be possible to receive a message and/or communicate selectively according to user's set up. In that case, when a message is received or a telephone call is received, while the garbage collection process is being performed, it is possible to check the message or answer the telephone by stopping the garbage collection process and converting the state of the mobile terminal from the safe mode back to the idle state.
In addition, when the FS_module 200 determines that the garbage collection is finished, the MC_module 300 converts the sate of the mobile terminal from the safe mode into the idle state, in accordance with one embodiment.
Referring to FIG. 2 , a user may set up garbage collection performing conditions through the key input unit of the mobile terminal (S 10 ). Afterward, the mobile terminal determines whether the user setting conditions are satisfied (S 20 ). When the conditions are satisfied, the mobile terminal is converted from the idle state into the safe mode in order to prevent interruptions from the outside and to perform a stable garbage collection procedure (S 30 ).
In one embodiment, the garbage collection conditions comprise judging whether the garbage collection is performed when the mobile terminal is idle or when garbage is greater than a threshold, or immediately. If the user sets up a condition to perform the garbage collection when the terminal is idle, the mobile terminal determines satisfaction of the condition by sensing if the terminal is inactive, for example.
If the user sets a condition to perform the garbage collection process when garbage is greater than a threshold, satisfaction of the condition is determined by checking the memory capacity and garbage stored. In addition, if the user sets a condition to perform the garbage collection immediately, the mobile terminal generates a control signal to force the garbage collection immediately.
When the mobile terminal is switched to safe mode, garbage collection is performed (S 40 ). The mobile terminal notifies the user of the beginning of the garbage collection process through display of a character or an icon on the display unit, sound generated from the speaker unit, vibration, etc. (S 50 ). Similarly, after the garbage collection process is completed (S 60 ), the mobile terminal notifies the user that the garbage collection process has ended by displaying a character or an icon on the display unit, or a sound generated from the speaker unit, vibration of the terminal, etc. (S 70 ). Thereafter, the safe mode is switched to the idle state (S 80 ).
As described-above, in the garbage collection method for a mobile terminal in accordance with one embodiment of the invention, by performing garbage collection in the safe mode, it is possible to avoid unwanted interruptions in order to make the memory perform the garbage collection under stable conditions.
In addition, in the garbage collection method for the mobile terminal in accordance with one embodiment of the present invention, a user can set up garbage collection conditions in a file system implemented on a large capacity memory when the mobile terminal user is notified of garbage collection proceedings and the user can perform garbage collection as occasion demands.
The embodiments described above are to be considered in all aspects as illustrative only and not restrictive in any manner. Thus, other exemplary embodiments, system architectures, platforms, and implementations that can support various aspects of the invention may be utilized without departing from the essential characteristics described herein. These and various other adaptations and combinations of features of the embodiments disclosed are within the scope of the invention. The invention is defined by the claims and their full scope of equivalents. | A garbage collection method is provided. The method comprises setting at least a garbage collection condition for the mobile terminal; converting a state of the mobile terminal from a first state to a second state when the at least one garbage collection condition is met; and starting a garbage collection procedure while the mobile terminal is in the first state, wherein in the first state the garbage collection procedure is not interrupted by an external event. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
Disclosed is a stone material that has had its natural color enhanced by heating to a specific temperature. More specifically, the subject invention entails selecting a suitable stone material and heating that stone material through at least one and usually two stages of heating to produce a product that has its colors greatly enhanced over the starting shades of the stone material.
2. Description of the Background Art
Heating has been utilized in the process of thoroughly drying and curing glazes used on pottery and tiles for centuries. Depending upon the exact composition of a glaze or its equivalent and the application procedure, various colors and textures can be generated for the pottery and tiles. However, a color enhancement of the underlying material itself (clays, common stone materials, and the like) is not accomplished without the use of a glaze or similar added substance.
It is also noted that the heating of highly colored and hydrated chemicals (like copper (II) sulfate pentahydrate and many others) produces products that are much less intensely colored (bright blue to bluish-white for the change in heated copper (II) sulfate pentahydrate). Heat dehydrated or even oxidized inorganics simply are less intensely colored than the original hydrated starting materials.
Specifically, U.S. Pat. No. 5,084,909 describes color enhancement brought about in natural and synthetic gem materials by high energy gamma ray fields for extended periods of time (50 to 1000 hours). High energy radiation fields are necessary for this process. It is extremely interesting to note that disclosed in this reference the inventor utilized heat to bleach or remove unwanted colors from the gems (either before or after a well known color enhancement procedure that involved electron bombardment). Therefore, this reference clearly teaches that heat has been utilized not to enhance color but to lessen color intensity in at least gem-type materials.
U.S. Pat. No. 5,477,055 presents a thorough review of the history of coloring precious or semi-precious gem stones via single or combined radiation treatments. The color enhancement process related is a two step method that includes fast neutron irradiation at between 350° C. to 600° C. followed by gamma ray or electron bombardment. Higher temperatures tend to fragment the gem stones. The elevated temperatures (above room temperature) tend to reduce unwanted side (blue-gray) colors.
Presented in U.S. Pat. No. 4,749,869 is a process for irradiating topaz and the product resulting therefrom. A three step method of color enhancement is described in which a sample stone is: 1) exposed to high energy neutrons; 2) exposed to electrons; and 3) heated to between 250° F. (121° C.) and 900° F. (482° C.). The heating step tends to "bleach-out" or remove unwanted side colors, thereby enhancing the desired blue color.
Diamonds may be heat treated to increase desirable colorations. U.S. Pat. No. 2,945,793 illustrates this approach to coloring diamonds. Irradiation by electrons in followed by heating to about 500° C. to, once again, decrease undesirable tints within the diamond.
U.S. Pat. No. 5,568,391 shows an automated tile mosaic creation system in which one step involves heating a glazed tile. The firing of the tiles is merely to cure the glaze into the desired final shade and hardness.
The foregoing patents reflect the state of the art of which the applicant is aware and are tendered with the view toward discharging applicant's acknowledged duty of candor in disclosing information which may be pertinent in the examination of this application. It is respectfully submitted, however, that none of these patents teach or render obvious, singly or when considered in combination, applicant's claimed invention.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a stone product having an enhanced coloration over the natural material and a method of producing color enhancement.
Another object of the present invention is to supply a sandstone product that has its color enhanced by a heating process over naturally occurring colorations.
A further object of the present invention is to disclose a stone product having an enhanced color produced by a two step method requiring heating.
Disclosed is a product and a method of producing the product. More specifically, a the product is a color enhanced stone material which is generated by the series of steps. The method of producing an enhancement in the natural coloration of a sample stone material comprises the steps of selecting the sample stone material having suitable characteristics for the color enhancement method and heating the sample stone material to a first temperature for a desired period of time. Usually, the first temperature is between 1200° F. and 1800° F. and more preferably the first temperature is about 1500° F. The length of time heating occurs at the first temperature can vary from thirty minutes to several hours and is usually about two hours. Commonly, the sample stone material is sandstone shaped into a suitable form, preferably a tile (flattened and generally rectangular to square in shape), for the color enhancement method.
Often, the subject method further comprises the steps of coating the sample stone material, after heating the sample stone material to the first temperature, with a glaze and heating the glazed sample stone material to a second temperature. Usually, the second heating is to a temperature between 1800° F. and 2500° F. and more usually to a temperature of about 2000° F. The final stone product has colors that enhanced well above the colors originally present in the initial sample stone.
Other objects, advantages, and novel features of the present invention will become apparent from the detailed description that follows, when considered in conjunction with the associated drawings.
DESCRIPTION OF THE PREFERRED EMBODIMENT
A preferred embodiment of the subject invention comprises a process for creating or manufacturing stone items. Stone items may include, but not be limited to, tiles, building stones, patio stones or pavers, flag or cobble stones, and the like. For exemplary intentions only, a distinctive and brightly colored tile for decorative purposes is useful and highly desired by many individuals. Such tiles might find usage in floors, counter tops, wall decorations, artistic creations, and the like. The subject process or method produces stone products such as tiles that have dramatically increased or enhanced colors over the initial or natural colors found in the stone.
Frequently, acceptable stone is obtained from a rock quarry or similar source in various shapes, sizes, and thicknesses. For exemplary purposes only and not by way of limitation, tiles will be used as the product to be used in the subject process, but other equivalent, like, or analogous types of products are considered to be within the realm of this disclosure. For tiles, the variously shaped and sized stones are cut by saws into tiles sized according to their end usage. Typically, common floor tiles are cut to about 111/2 inches square, 111/2 by 51/2 inches, and 51/2 by 51/2 inches. Counter top and shower tiles are usually 3/8 inch thick and again sized for end usage, but mainly 3 by 3 inches.
The stone tiles can be made from any type of stone including sandstone, marble, slate, granite, and the like. For the subject method the material from which the tiles are fabricated needs to be a composition that is subject to color enhancement upon the heating steps detailed below. Sandstone appears to have suitable color enhancement properties for the subject method, but other stone materials are acceptable, as long as the color intensification occurs upon applying the subject process.
Once again, the subject process or method is utilized with any type of stone having chemical and/or physical properties that permit the stone to enhance its colors during the subject method. The exact chemical and/or physical property constraints on the stone is not entirely clear, however, a suitable sandstone composition is described below in the EXAMPLES section of this disclosure. The particular pieces of stone utilized to reduce to practice this invention were sandstone samples obtained from Oklahoma, but similar stone or sandstone materials are acceptable as long as they undergo the color enhancement as a result of the subject process.
After cutting the sandstone tiles, the tiles are usually air dried at ambient temperature before the subject heating process is initiated. The air drying may be facilitated by standard mechanical and electrical means such as heaters, blowers, vacuum equipment, heating lamps, ovens, and the like. The time for the air drying may vary from about thirty minutes to several hours or several days, with an overnight drying generally acceptable.
After the initial drying, usually, the selected and shaped stone (tile or other shape) is placed in a kiln, oven, furnace, or the equivalent and heated to a first temperature of between about 1200° F. and 1800° F., preferably about 1500° F. for between thirty minutes to several hours or days, depending upon the desired level of color enhancement. Following the first heating, the stone is cooled to ambient temperature.
The initial first heating serves at least three functions: 1) the original colors are intensified and patterns in the stone appear more pronounced (some of the original colors may not be altered, but clearly many are in acceptable stone materials); 2) it removes most, if not all, of the remaining moisture or liquids from the tile thereby reducing warping of the tile; and 3) it stresses defective tiles and any defects are usually detected at this point.
A second heating usually follows the first heating in which the previously heated stone is first glazed with glazing material such as glass glaze or its equivalent. Frequently, the glazing process coats the entire outside of the stone with glaze. Generally, each stone product that has been heated to the first temperature and wetted with glaze is placed in a tray filed with sand. A layer of sand adheres to the bottom of each stone item. The glazed first heated stone is then heated in the same or similar heating device to a second temperature. The second temperature is usually between 1800° F. and 2500° F., preferably, about 2000° F. The second heating is often for a period of time between about 30 minutes and several hours or days, more usually about one to six hours, preferably about two hours.
After the second heating the stone products or tiles are allowed to cool. When removed from the trays, the stones or tiles have a rough lower surface, due to the adhered and baked sand layer. For tiles, the rough under-surface aids in producing a good bond when the tiles are fitted and glued into position on a floor, counter-top, shower, and the like.
EXAMPLES
Type of Acceptable Sample
A typical sample of acceptable stone for the subject process (acceptable stone is stone that when heated in the subject process has its color intensified or enhanced) is analyzed below (analyzed by Nevada Bureau of Mines and Geology Laboratories, Mail Stop 178, Reno, Nev. 89557):
Sample Type: A piece of dense, fine- to very fine-grained sandstone, consisting chiefly of quartz grains with minor muscovite flakes, and all are cemented by ferruginous matter.
Sample Analysis:
TABLE 1______________________________________Elemental Part-Per Million AnalysisElement Parts per Million (ppm)______________________________________Barium 22Cobalt 2Chromium 414Gallium 6Niobium 8Nickel 16Rubidium 7Strontium 21Lead <10Vanadium 28Tungsten <10Yttrium 16Zinc 39Zirconium 351Tin <10______________________________________
TABLE 2______________________________________Compound Percentage AnalysisCompound Percentage (%)______________________________________SiO.sub.2 94.6TiO.sub.2 0.248Al.sub.2 O.sub.3 2.19Fe.sub.2 O.sub.3 1.96MnO 0.019MgO <0.2CaO 0.011Na.sub.2 O 0.325K.sub.2 O 0.147P.sub.2 O.sub.5 0.037LOI (gases) 1.15TOTAL 100.7______________________________________
Color Enhancement Process
A sample of the above described sandstone typically has a swirled pattern with brown to reddish colors. Tiles cut to various sizes were fabricated from the above sandstone. Each tile was air dried and then heated in a kiln to about 1500° F. for about two hours. Each tile was coated with traditional glass glaze and placed in trays of sand. The tiles were then heated for about two hours at about 2000° F. After cooling, the tiles had a greatly enhanced intensity of colors and the swirled patterns were much more apparent. Presumably, the pattern enhancement results from an actual gradient of individual color enhancements that intensify some colors (the original darker colors) more than other colors (the original lighter colors). Of course, depending upon the exact sandstone makeup, some initial colors may or may not be intensified.
The invention has now been explained with reference to specific embodiments. Other embodiments will be suggested to those of ordinary skill in the appropriate art upon review of the present specification.
Although the foregoing invention has been described in some detail by way of illustration and example for purposes of clarity of understanding, it will be obvious that certain changes and modifications may be practiced within the scope of the appended claims. | A method of producing an enhancement in the natural coloration of a sandstone comprises selecting a sample of sandstone having suitable characteristics for the color enhancement method, forming the sandstone sample into a tile, and then heating the tile to a first temperature of between 1200° F. and 1800° F. Additional steps is the method comprise coating the first heated tile with a glaze and heating the glazed first heated tile to a second temperature of between 1800° F. and 2500° F. | 2 |
This application claims the priority of the Chinese patent application, with the application no. 201310481837.8, filed with State Intellectual Property Office of China on 15 Oct. 2013 and entitled “LED Light Source Performance Compensation Apparatus, Device and Application Thereof”, which prior application is incorporated herein by reference in its entirety.
FIELD OF THE INVENTION
The present invention relates to a light source performance compensation apparatus, a device and an application thereof and, particularly, to an LED light source performance compensation apparatus, a device and an application thereof.
BACKGROUND
With regard to the existing light sources that generate white light for lighting, from initial incandescent lamps and fluorescent lamps to relatively new LED light sources that are currently used, these light sources mentioned above generally cause, when generating white light, that the white light generated thereby exists certain deficiency in performance due to the limitation of factors, such as the compositional design or the structural design of the light sources per se.
For example, the existing white-light LED commonly used. The LED (light-emitting diode) device, as a novel solid light source, not only has the advantages of a low power consumption, a small volume, a fast response speed, a long working life, being liable to light adjustment and colour adjustment, being energy saving and environmentally friendly, etc., but also gains significant advantages over traditional light sources, such as an incandescent lamp and a fluorescent lamp, in terms of production, manufacturing and applicability, and therefore it has obtained considerable developments since it was born in the sixties. At present, the LED device has been widely applied in a plurality of fields of lighting, such as street lamp lighting, landscape lighting, large screen display, traffic lights and interior lighting.
The existing LED light sources are mainly obtained by exciting yellow luminescent powder with blue light, or exciting red, yellow and green luminescent powder with a blue light chip, while the traditional process is to mix the yellow luminescent powder and silica gel and then coat the mixture on the blue light chip, and cure the silica gel by heating, or to make the LED device by arranging the luminescent powder and the blue chip apart.
However, it can only be determined whether an LED device formed by means of a traditional process complies with the performance requirements, i.e. whether the performances, such as a colour temperature, a colour rendering index, a colour tolerance, a fluctuation depth, light effect and an light emergent angle, are within target ranges, by testing a finished LED light source, and if the performances exceed the target ranges, the device is an unqualified product. With regard to such an unqualified product, the existing manufacturers generally cannot effectively process it.
SUMMARY OF THE INVENTION
In view of this, the present invention provides an LED light source performance compensation apparatus, which can effectively regulate light performance parameters of an LED light source, thereby remedying the defects of the secondary light emitted by an existing finished LED light source in terms of light performance parameters.
In order to solve the above-mentioned technical problem, the technical solution of a first aspect provided in the present invention is an LED light source performance compensation apparatus, comprising: a light transmissive supporting member, wherein the light transmissive supporting member is provided with a light performance parameter regulation member; and after secondary light of which the wavelength is 380 nm-780 nm and which is emitted by an LED light source passes through the performance compensation apparatus, light performance parameters are adjusted.
The technical solution of a second aspect provided in the present invention is a preparation method for the aforementioned LED light source performance compensation apparatus, the light source performance compensation apparatus comprising a light wavelength conversion component and a light transmissive binding material, the light wavelength conversion component is fluorescent powder or a fluorescent film; several grooves are provided on the light transmissive supporting member, and the light transmissive binding material is provided in the grooves; the fluorescent powder or the fluorescent film is provided in the light transmissive binding material; and the light source performance compensation apparatus is prepared by using an IMD process, wherein the IMD process is any one selected from IML, IMF and IMR.
The technical solution of a third aspect provided in the present invention is an application of the aforementioned LED light source performance compensation apparatus in regulation of light performance parameters of secondary light of which the wavelength is 380 nm-780 nm and which is emitted by an LED light source.
The technical solution of a fourth aspect provided in the present invention is a white-light LED light-emitting device, comprising: a white-light LED light source and an LED light source performance compensation apparatus, wherein the LED light source performance compensation apparatus comprises: a light transmissive supporting member, wherein the light transmissive supporting member is provided with a light performance parameter regulation member; the light performance parameter regulation member comprises a light wavelength conversion component and/or a light transmissive binding material; and after white light emitted by the white-light LED light source passes through the performance compensation apparatus, light performance parameters are adjusted.
The LED light source of the present invention is a concept relative to the existing LED chips, and light emitted by the LED chip is light directly emitted from a semiconductor constituting the chip, i.e. primary light. However, the light emitted by the LED light source of the present invention is secondary light, i.e. the secondary light generated after wavelength conversion is performed via an existing light wavelength conversion component, such as fluorescent powder, on the primary light emitted from the semiconductor of the chip, wherein the secondary light emitted by the LED light source is visible light of which the wavelength is 380 nm-780 nm.
The LED light source performance compensation apparatus of the present invention is applied to regulation of the existing LED light source in performance, and the main principle of regulation thereof is to regulate light performance parameters of secondary light emitted by an LED light source via a light performance parameter regulation member, e.g., the combination of a light wavelength conversion component and/or a light transmissive binding material with a light transmissive supporting member, for example, non-afterglow luminescent powder or afterglow luminescent powder in the light wavelength conversion component can be used to regulate an afterglow time thereof, or luminescent powder, such as fluorescent powder, with different colours can be used to regulate the light performance parameters, such as a colour temperature, the light effect, a colour rendering index, a colour tolerance, an emitted light colour, a proportion of blue light and a fluctuation depth, of the secondary light emitted by the LED light source, and thus the LED light source performance compensation apparatus is especially suitable for white light emitted by the existing finished white-light LED light source.
The present invention is to regulate light performance parameters of the existing finished LED light source product by adding the LED light source performance compensation apparatus of the present invention to the periphery of the LED light source and using the function of a light performance parameter regulation member, such as a light wavelength conversion component and/or a light transmissive binding material.
The light wavelength conversion component of the present invention can be a type of luminescent powder, which is a kind of luminescent powder for an LED. The existing luminescent powder can be divided into three kinds: fluorescent powder, phosphorescence powder and afterglow powder.
The light transmissive binding material of the present invention can be a solid glue and a semi-solid glue at normal temperature: the form of elastic gel, brittle gel and jelly; and the use of the elastic gel in a mounting process can facilitate matching and mounting a protruded LED light source lamp bead.
The light source performance compensation apparatus of the present invention can also regulate the light effect of the light emitted by the LED light source by separately providing the light transmissive binding material, and can also further preferably combine the light transmissive binding material with the light wavelength conversion component so as to realize the regulation of the combination of the above-mentioned various performances.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1-4 are structural schematic diagrams of particular embodiments of an LED light source performance compensation apparatus of the present invention in Embodiment I;
FIGS. 5-8 are structural schematic diagrams of particular embodiments of an LED light source performance compensation apparatus of the present invention in Embodiment II;
FIGS. 9-12 are structural schematic diagrams of particular embodiments of an LED light source performance compensation apparatus of the present invention in Embodiment III;
FIGS. 13-15 are structural schematic diagrams of particular embodiments of an LED light source performance compensation apparatus of the present invention in Embodiment IV;
FIGS. 16-18 are structural schematic diagrams of particular embodiments of an LED light source performance compensation mechanism of the present invention in Embodiment V; and
FIG. 19 is a measurement diagram of the performance parameter of a proportion of blue light in Embodiment VI.
DETAILED DESCRIPTION
To help those skilled in the art better understand the technical solutions of the present invention, the present invention will be further described in detail in combination with particular embodiments below.
The fluorescent film of the present invention is a film made from fluorescent powder. The present invention preferably uses the fluorescent powder or a fluorescent film as a light wavelength conversion component, which can also select different fluorescent powder or fluorescent films to regulate different performance parameters of light according to different requirements, in addition to regulating the wavelength of light. For example, when only a light transmissive binding material is used, the light effect of secondary light emitted by an LED light source can be regulated; and the refractive index of the light transmissive binding material is greater than that of the air, so that the light effect of the secondary light can be changed by changing the angle of light refraction. The light wavelength conversion component can also be used alone, which functions, by means of wavelength convention, to regulate the performance parameters, such as the colour, the proportion of blue light, the colour temperature and the colour tolerance, of the secondary light emitted by the LED light source. The combination of the light transmissive binding material and the light wavelength conversion component can also be further used, especially the fluorescent powder or the fluorescent film, etc., thereby functioning to regulate the performance parameters, such as the colour temperature, the light effect, the colour rendering index, the colour tolerance, the emitted light colour, the proportion of blue light and the fluctuation depth, of the secondary light emitted by the LED light source.
The following are only some of the preferred embodiments of the present invention, and the protection scope of the present invention is not limited to the embodiments cited in the present invention.
Embodiment I: A Light Performance Parameter Regulation Member is Located Inside a Light Transmissive Supporting Member
As shown in FIGS. 1-2 , the LED light source performance compensation apparatus comprises a light transmissive supporting member and a light performance parameter regulation member, wherein the light performance parameter regulation member is located inside the light transmissive supporting member. The LED light source performance compensation apparatus covers the periphery of an LED light source, wherein an intervening connection part between the LED light source and the LED light source performance compensation apparatus can be filled with gas, such as air, nitrogen and helium, and can also be in a vacuum state, and even the approach of completely or partially filling the above-mentioned intervening connection part with a light transmissive binding material can be used.
The light performance parameter regulation member can be a light wavelength conversion component which can be formed as a film separately or be provided inside the light transmissive supporting member in a dispersed manner, with reference to the schematic diagram of FIG. 1 or 2 .
FIG. 1 is a structural schematic diagram of an implementation in which a light wavelength conversion component is formed as a film separately and provided inside a light transmissive supporting member, comprising a light wavelength conversion component 102 , a light transmissive supporting member 101 and an LED light source 103 ; and a part 104 between the light transmissive supporting member 101 and the LED light source 103 can be gas: such as air, nitrogen and helium, and can also be in a vacuum state; and the light wavelength conversion component 102 shown in FIG. 1 can be preferably a luminescent film in luminescent powder, and can even be further preferably a fluorescent film.
FIG. 2 is a structural schematic diagram of an implementation in which a light wavelength conversion component is provided inside a light transmissive supporting member in a dispersed manner, comprising a light wavelength conversion component 202 , a light transmissive supporting member 201 and an LED light source 203 ; and a part 204 between the light transmissive supporting member 201 and the LED light source 203 can be gas: such as air, nitrogen and helium, and can also be in a vacuum state.
The LED light source in FIG. 1 or 2 can be preferably a white-light LED light source, and can even be further preferably an LED chip that emits blue light, wherein the periphery of the LED chip is provided with a white-light LED light source having yellow-light fluorescent powder or blue, green and red-light fluorescent powder.
The light performance parameter regulation member can also be a light wavelength conversion component and a light transmissive binding material, which can use the approach of mixing by film forming or being dispersedly located inside a light transmissive supporting member, with reference to the schematic diagram of FIG. 3 or 4 .
FIG. 3 is a structural schematic diagram of the implementation in which a light wavelength conversion component and a light transmissive binder are mixed by film forming and provided inside a light transmissive supporting member, comprising a light wavelength conversion component 302 , a light transmissive binder 305 , a light transmissive supporting member 301 and an LED light source 303 ; and a part 304 between the light transmissive supporting member 301 and the LED light source 303 can be gas: such as air, nitrogen and helium, and can also be in a vacuum state; and the light wavelength conversion component 302 shown in FIG. 3 can be preferably a luminescent film in luminescent powder, and can even be further preferably a fluorescent film.
FIG. 4 is a structural schematic diagram of the implementation in which a light wavelength conversion component and a light transmissive binder being mixed and provided inside a light transmissive supporting member in a dispersed manner, comprising a light wavelength conversion component 402 , a light transmissive binder 405 , a light transmissive supporting member 401 and an LED light source 403 ; and a part 404 between the light transmissive supporting member 401 and the LED light source 403 can be a gas: such as air, nitrogen and helium, and can also be in a vacuum state.
The LED light source in FIG. 3 or 4 can be preferably a white-light LED light source, and can even be further preferably an LED chip that emits blue light, wherein the periphery of the LED chip is provided with a white-light LED light source having yellow-light fluorescent powder or blue, green and red-light fluorescent powder.
The light wavelength conversion component in the present embodiment I can be fluorescent powder, phosphorescence powder and afterglow powder or any combination of the above-mentioned three powder; the light transmissive supporting member can be made from any light transmissive material, for example, a light transmissive component such as a lens and a light transmissive film, which can function to support a light performance parameter regulation member; and the light transmissive binding material can be selected from a solid and semi-solid glue or gel at normal temperature, and preferably is elastic gel.
A preparation method for the white light source performance compensation apparatus in this embodiment I can use a common existing preparation process, such as the process of injection moulding.
Embodiment II: A Light Performance Parameter Regulation Member is Located on an Outer Surface of a Light Transmissive Supporting Member
As shown in FIGS. 5-8 , the LED light source performance compensation apparatus comprises a light transmissive supporting member and a light performance parameter regulation member, wherein the light performance parameter regulation member comprises a light wavelength conversion component and a light transmissive binding material; and the light wavelength conversion component is provided on an outer surface of the light transmissive supporting member by means of a binding effect of the light transmissive binding material. The LED light source performance compensation apparatus covers the periphery of an LED light source, wherein a connection part between the LED light source and the LED light source performance compensation apparatus can be gas: such as air, nitrogen and helium, and can also be in a vacuum state, and even can use the method of completely filling or partially filling a light transmissive binding material in the above-mentioned connection part.
The light performance parameter adjustment member can also be formed as a film or provided on the outer surface of the light transmissive supporting member in a dispersed manner, with reference to the schematic diagram of FIG. 5 or 6 .
FIG. 5 is a structural schematic diagram of an implementation in which a light wavelength conversion component is formed as a film separately and provided inside an outer surface of a light transmissive supporting member by means of the binding effect of a light transmissive binding material, comprising a light wavelength conversion component 502 , a light transmissive supporting member 501 , a light transmissive binding material 505 and an LED light source 503 ; and a part 504 between the light transmissive supporting member 501 and the LED light source 503 can be gas: such as air, nitrogen and helium, and can also be in a vacuum state; and the light wavelength conversion component 502 shown in FIG. 5 can be preferably a luminescent film in luminescent powder, and can even be further preferably a fluorescent film.
FIG. 6 is a structural schematic diagram of an implementation in which a light wavelength conversion component is provided inside an outer surface of a light transmissive supporting member in a dispersed manner by means of the binding effect of a light transmissive binding material, comprising a light wavelength conversion component 602 , a light transmissive supporting member 601 , a light transmissive binding material 605 and an LED light source 603 ; and a part 604 between the light transmissive supporting member 601 and the LED light source 603 can be gas: such as air, nitrogen and helium, and can also be in a vacuum state.
The LED light source in FIG. 5 or 6 can be preferably a white-light LED light source, and can even be further preferably an LED chip that emits blue light, wherein the periphery of the LED chip is provided with a white-light LED light source having yellow-light fluorescent powder or blue, green and red-light fluorescent powder.
The LED light source performance compensation apparatus can be separately provided between the light transmissive supporting member and the LED light source using a light transmissive binding material; and the refractive index of the light transmissive binding material is generally greater than that of the gas, especially the air. This implementation can excellently improve the light effect of secondary light emitted by the LED light source. Refer to the structural schematic diagram of FIG. 7 or 8 .
What is shown in FIG. 7 comprises a light wavelength conversion component 702 , a light transmissive supporting member 701 , a light transmissive binder 705 and an LED light source 703 ; and
what is shown in FIG. 8 comprises a light wavelength conversion component 802 , a light transmissive supporting member 801 , a light transmissive binder 805 and an LED light source 803 .
The light wavelength conversion component in the present embodiment II can be fluorescent powder, phosphorescence powder and afterglow powder or any combination of the above-mentioned three powder; the light transmissive supporting member can be made from any light transmissive material, for example, a light transmissive component such as a lens and a light transmissive film, which can function to support the light wavelength conversion component; and the light transmissive binder can be selected from a solid and semi-solid glue or gel at normal temperature.
A preparation method for the white light source performance compensation apparatus in this embodiment II can use a common existing preparation process, for example, an IMD process, IMD being short for an in-mold decoration technology, can be divided into IML, IMF and IMR. The IML is in-mold labelling. The surface of a label is a layer of hardened transparent thin film, and the middle is a printed pattern layer; and by means of an injection manufacturing process, the back of the label is combined with plastic, with luminescent powder printing ink of the printed pattern layer being sandwiched, so as to prevent the surface of a product from being shaved, and can keep the colour vibrant for a long term without fading easily. In the manufacturing process, the label is not stretched with a small curve surface, and is mainly used for 2D products. The IMF is in-mold forming, and the principle thereof is the same as that of the IML. The IMF process is as follows: the luminescent powder printing ink is firstly printed on a layer of thin film (the material thereof being PC or PET) with the thickness of approximately 0.05 mm-0.5 mm, the printed thin film is punched and high-pressure shaped to obtain a trimmed label, and then the label is placed into an injection machine and formed together with plastic particles in mold after being positioned by a mould positioning mechanism. In the manufacturing process, the label is highly stretched, and is mainly used for 3D products. In addition, the IMR is in-mold roller/reprint, and the difference lies in that there is no layer of transparent protective film on the surface of a final product.
Embodiment III: A Light Performance Parameter Regulation Member is Located Between an Inner Surface of a Light Transmissive Supporting Member and a Light Source
As shown in FIGS. 9-12 , the LED light source performance compensation apparatus comprises a light transmissive supporting member and a light performance parameter regulation member; the LED light source performance compensation apparatus covers the periphery of an LED light source; and a spacial part of an intervening connection between the LED light source and the LED light source performance compensation apparatus can be completely filled with a light wavelength conversion component, a light transmissive binding material, or a mixed composition of the light wavelength conversion component and the light transmissive binding material. The spacial part of an intervening connection between the above two can also be partially filled with the light wavelength conversion component, the light transmissive binding material, or the mixed composition of the light wavelength conversion component and the light transmissive binding material, and if partial filling is adopted, a spacial part that is not filled can be gas: such as air, nitrogen and helium, and can also be in a vacuum state, etc.
The light performance parameter regulation member can comprise a light wavelength conversion component and a light transmissive binding material, wherein the light wavelength conversion component is provided between an inner surface of a light transmissive supporting member and an LED light source by means of a binding effect of the light transmissive binding material. The light wavelength conversion component can also be formed as a film or provided in a spatial part between the inner surface of the light transmissive supporting member and the LED light source in a dispersed manner, with reference to the schematic diagram of FIG. 9 or 10 .
FIG. 9 is a structural schematic diagram of an implementation in which a light wavelength conversion component is formed as a film and provided in a spatial part between an inner surface of a light transmissive supporting member and an LED light source, comprising a light wavelength conversion component 902 , a light transmissive supporting member 901 , a light transmissive binding material 905 and an LED light source 903 ; and the light wavelength conversion component 902 shown in FIG. 9 can be preferably a luminescent film in luminescent powder, and can even be further preferably a fluorescent film.
FIG. 10 is a structural schematic diagram of an implementation in which a light wavelength conversion component and a light transmissive binding material are jointly provided in a spatial part between an inner surface of a light transmissive supporting member and an LED light source in a dispersed manner, comprising a light wavelength conversion component 1002 , a light transmissive supporting member 1001 , a light transmissive binding material 1005 and an LED light source 1003 .
The LED light source in FIG. 9 or 10 can be preferably a white-light LED light source, and can even be further preferably an LED chip that emits blue light, wherein the periphery of the LED chip is provided with a white-light LED light source having yellow-light fluorescent powder or blue, green and red-light fluorescent powder.
The LED light source performance compensation apparatus of the present invention can also be provided between an inner surface of a light transmissive supporting member and an LED light source separately using a light transmissive binding material, as shown in FIGS. 11 and 12 .
FIG. 11 shows the case where a light transmissive binding material is completely filled between an inner surface of a light transmissive supporting member and an LED light source, comprising a light transmissive supporting member 1101 , a light transmissive binding material 1105 and an LED light source 1103 .
FIG. 12 shows the case where a light transmissive binding material is partially filled between an inner surface of a light transmissive supporting member and an LED light source, comprising a light transmissive supporting member 1201 , a light transmissive binding material 1205 and an LED light source 1203 ; and a part 1204 that is not filled with the light transmissive binding material can be gas: such as air, nitrogen and helium, and can also be in a vacuum state.
The LED light source in FIG. 11 or 12 can be preferably a white-light LED light source, and can even be further preferably an LED chip that emits blue light, wherein the periphery of the LED chip is provided with a white-light LED light source having yellow-light fluorescent powder or blue, green and red-light fluorescent powder.
The light wavelength conversion component in the present embodiment III can be fluorescent powder, phosphorescence powder and afterglow powder or any combination of the above-mentioned three powder; the light transmissive supporting member can be made from any light transmissive material, for example, a light transmissive component such as a lens and a light transmissive film, which can function to support the light wavelength conversion component; and the light transmissive binder can be selected from a solid and semi-solid glue or gel at normal temperature.
A preparation method for the white light source performance compensation apparatus in this embodiment III can use a common existing preparation process, such as an IMD process and a luminescent powder whitewashing process.
Embodiment IV: The Coverage Degree of an LED Light Source Performance Compensation Apparatus and an LED Light Source
The LED light source performance compensation apparatus of the present invention can use a light source plane that completely covers secondary light emitted by the LED light source, and can also use a light source plane that partially covers secondary light emitted by the LED light source. The LED light source performance compensation apparatus completely covering the light source plane can better improve the light effect and the colour temperature.
1. The LED Light Source Performance Compensation Apparatus Completely Covers the LED Light Source.
Reference can be made to FIG. 13 for the structural schematic diagram of this implementation, comprising an LED light source performance compensation apparatus 13 -A and an LED light source 1303 , wherein the LED light source performance compensation apparatus 13 -A completely covers a light source plane of light emitted by the LED light source 1303 ; the LED light source performance compensation apparatus can also contain a light transmissive supporting member and a light performance parameter regulation member, wherein the light performance parameter regulation member contains a wavelength conversion component and a light transmissive binding material; and the positional and connection relationships or compositions and the like among the light transmissive supporting member, the LED light source, the light wavelength conversion component and/or the light transmissive binding material can use any particular implementation of the aforementioned Embodiment I to Embodiment III.
2. The LED Light Source Performance Compensation Apparatus Partially Covers the Light Source Plane of the Light Emitted by the LED Light Source.
A. The LED Light Source Performance Compensation Apparatus Covers an Upper Surface Part of the Periphery of the LED Light Source.
Reference can be made to FIG. 14 for the structural schematic diagram of this implementation, comprising an LED light source performance compensation apparatus 14 -A and an LED light source 1403 , wherein the LED light source performance compensation apparatus 14 -A covers an upper surface part of the periphery of the LED light source 1403 , i.e. one of the implementations of partially covering a light source plane of light emitted by the LED light source 1403 . the LED light source performance compensation apparatus can also contain a light transmissive supporting member and a light performance parameter regulation member, wherein the light performance parameter regulation member contains a wavelength conversion component and a light transmissive binding material; and the positional and connection relationships or compositions and the like among the light transmissive supporting member, the LED light source, the light wavelength conversion component and/or the light transmissive binding material can all use any implementation of the aforementioned Embodiment I to Embodiment III.
B. The LED Light Source Performance Compensation Apparatus Covers a Side Surface Part of the Periphery of the LED Light Source.
Reference can be made to FIG. 15 for the structural schematic diagram of this implementation, comprising an LED light source performance compensation apparatus 15 -A and an LED light source 1503 , wherein the LED light source performance compensation apparatus 15 -A covers a side surface part of the periphery of the LED light source 1503 , i.e. one of the implementations of partially covering a light source plane of light emitted by the LED light source 1503 . the LED light source performance compensation apparatus can also contain a light transmissive supporting member and a light performance parameter regulation member, wherein the light performance parameter regulation member contains a wavelength conversion component and a light transmissive binding material; and the positional and connection relationships or compositions and the like among the light transmissive supporting member, the LED light source, the light wavelength conversion component and/or the light transmissive binding material can all use any implementation of the aforementioned Embodiment I to Embodiment III.
Embodiment V: The Positional Relationship Between a Light Wavelength Conversion Component and/or a Light Transmissive Binding Material and Multiple Layers of Light Transmissive Supporting Members
In the LED light source performance compensation apparatus of the present invention, a single layer of light wavelength conversion component and/or light transmissive binding material can be used to connect to a single layer of light transmissive supporting member, and a connection combination of a single layer of light wavelength conversion component and/or light transmissive binding material and multiple layers of light transmissive supporting members can also be used, and a connection combination of multiple layers of light wavelength conversion components and/or light transmissive binding materials and multiple layers of light transmissive supporting members can further be used. Reference can be made to FIG. 16 for the particular implementation, comprising: a light wavelength conversion component 1602 , a light transmissive binding material 1605 , a light transmissive supporting member 1601 and an LED light source 1603 ; and a part 1604 between two adjacent layers of light transmissive supporting members 1601 can be gas: such as air, nitrogen and helium, and can also be in a vacuum state.
The LED light source performance compensation apparatus of the present invention can be applied to a single lamp bead and multiple lamp beads, preferably to the combination of multiple lamp beads; by means of this preferred approach, the LED light source performance compensation apparatus of the present invention can use the approach of providing a plurality of connection portions with the light wavelength conversion components and/or the light transmissive binding material on an integral light transmissive supporting member; and more preferably, the connection portions can be groove structures, wherein the groove structures match the positions of lamp beads of the LED light source. Further preferably, the light wavelength conversion component and/or the light transmissive binding material can be provided at a groove, so as to reduce the manufacturing cost of the LED light source performance compensation apparatus of the present invention, and facilitate assembling of a process of combining lamp beads. Reference can be made to FIGS. 17 and 18 for the structural schematic diagram of a particular implementation. FIG. 17 shows a top view of an LED light source performance compensation apparatus in which a plurality rows of light wavelength conversion components and a plurality rows of light transmissive binding materials are provided on a light transmissive supporting member. FIG. 18 is a front view of the structure shown in FIG. 17 , comprising a light wavelength conversion component 1702 , a light transmissive binding material 1705 , a light transmissive supporting member 1701 and an LED light source 1703 , wherein the light transmissive supporting member 1701 is provided with a groove 1706 .
Embodiment VI: Assembling Effect Experiment
The structures of the lamp beads of the LED light source in the preferred implementations in the aforementioned Embodiment I to Embodiment V are used to conduct an effect experiment of performance parameters of light; and reference is made to the structures of FIGS. 17 and 18 to prepare the LED light source performance compensation apparatus for test.
Blank control 1: an LED light source, wherein the LED light source is a concept relative to the existing LED chip, and light emitted by the LED chip is light directly emitted from a semiconductor constituting the chip, i.e. primary light. However, the light emitted by the LED light source of the present invention is secondary light, i.e. the secondary light generated after wavelength conversion is performed via an existing light wavelength conversion component, such as fluorescent powder, on the primary light emitted from the semiconductor of the chip, wherein the secondary light emitted by the LED light source is visible light of which the wavelength is 380 nm-780 nm.
Control 2: The implementation represented in FIG. 12 comprises a white-light LED light source, a light transmissive supporting member and a light transmissive binding material, wherein the light transmissive supporting member completely covers a light source plane of light emitted by the white-light LED light source, and the light transmissive binding material partially fills a spatial part between an inner surface of the light transmissive supporting member and the white-light LED light source; and the light transmissive binding material can use any of the existing light transmissive binding materials (EHA 3055 of KCC corporation), and the light transmissive binding material can be preferably one of silica gel, such as Dow Corning (OE-6336).
Control 3: The implementation represented in FIG. 11 comprises a white-light LED light source, a light transmissive supporting member and a light transmissive binding material, wherein the light transmissive supporting member completely covers a light source plane of light emitted by the white-light LED light source, and the light transmissive binder completely fills a spatial part between an inner surface of the light transmissive supporting member and the white-light LED light source; and the light transmissive binding material can use any of the existing light transmissive binding materials (EHA 3055 of KCC corporation), and the light transmissive binding material can be preferably one of silica gel, such as Dow Corning (OE-6336).
Control 4: The implementation represented in FIG. 10 comprises a white-light LED light source, a light transmissive supporting member, a light transmissive binding material and a light wavelength conversion component, wherein the light transmissive supporting member completely covers a light source plane of light emitted by the white-light LED light source, and the light transmissive binding material and the light wavelength conversion component are jointly filled in a spatial part between an inner surface of the light transmissive supporting member and the white-light LED light source in a dispersed manner; the light transmissive binding material can use any of the existing light transmissive binding materials (EHA 3055 of KCC corporation), and the light transmissive binding material can be preferably one of silica gel, such as Dow Corning (OE-6336); and the light wavelength conversion component can be selected from any of the existing luminescent powder compositions, preferably fluorescent powder, particularly yellow-light fluorescent powder, red-light fluorescent powder and green-light fluorescent powder, etc.
Control 5: The implementation represented in FIG. 9 comprises a white-light LED light source, a light transmissive supporting member, a light transmissive binding material and a light wavelength conversion component, wherein the light transmissive supporting member completely covers a light source plane of light emitted by the white-light LED light source, the light transmissive binding material fills a spatial part between an inner surface of the light transmissive supporting member and the white-light LED light source, and the light wavelength conversion component is provided inside the light transmissive binding material after film forming; the light transmissive binding material can use any of the existing light transmissive binding materials (EHA 3055 of KCC corporation), and the light transmissive binding material can be preferably one of silica gel, such as Dow Corning (OE-6336); and the light wavelength conversion component can be selected from any of the existing luminescent powder compositions, preferably fluorescent powder, particularly yellow-light fluorescent powder, red-light fluorescent powder and green-light fluorescent powder, etc.
After the selection of the white-light LED light source and the selection of various compositions is performed in the implementations of the structures of the above-mentioned blank controls 1 and 2 and controls 3-6, the light performance parameters thereof are measured respectively; and the measurement method used is to use a distant DMS-80 spectrum analyser. Reference is made to Table I to Table V below for measured data.
TABLE I
Light wavelength
Type of light
Light transmissive
conversion
Light effect
source
binding material
component
(1 m/W)
Blank control 1
White-light LED
—
—
92.2
light source
Yellow-light LED
—
—
66.5
light source
Blue-light LED
—
—
7.4
light source
Green-light LED
—
—
42.0
light source
Red-light LED
—
—
30.9
light source
Control 2
White-light LED
EHA3055 of KCC
—
92.4
light source
corporation
Yellow-light LED
EHA3055 of KCC
—
66.6
light source
corporation
Blue-light LED
EHA3055 of KCC
—
7.4
light source
corporation
Green-light LED
EHA3055 of KCC
—
42.1
light source
corporation
Red-light LED
EHA3055 of KCC
—
30.9
light source
corporation
White-light LED
OE-6336 of Dow
—
94.9
light source
Corning
Yellow-light LED
OE-6336 of Dow
—
68.5
light source
Corning
Blue-light LED
OE-6336 of Dow
—
7.6
light source
Corning
Green-light LED
OE-6336 of Dow
—
43.2
light source
Corning
Red-light LED
OE-6336 of Dow
—
31.8
light source
Corning
Control 3
White-light LED
EHA3055 of KCC
—
95.0
light source
corporation
Yellow-light LED
EHA3055 of KCC
—
68.5
light source
corporation
Blue-light LED
EHA3055 of KCC
—
7.6
light source
corporation
Green-light LED
EHA3055 of KCC
—
43.3
light source
corporation
Red-light LED
EHA3055 of KCC
—
31.8
light source
corporation
White-light LED
OE-6336 of Dow
—
103.0
light source
Corning
Yellow-light LED
OE-6336 of Dow
—
74.2
light source
Corning
Blue-light LED
OE-6336 of Dow
—
8.3
light source
Corning
Green-light LED
OE-6336 of Dow
—
46.9
light source
Corning
Red-light LED
OE-6336 of Dow
—
34.5
light source
Corning
Control 4
White-light LED
EHA3055 of KCC
Red-light
90.0
light source
corporation
fluorescent powder
Yellow-light LED
EHA3055 of KCC
Red-light
64.9
light source
corporation
fluorescent powder
Blue-light LED
EHA3055 of KCC
Red-light
7.2
light source
corporation
fluorescent powder
Green-light LED
EHA3055 of KCC
Red-light
41.0
light source
corporation
fluorescent powder
Red-light LED
EHA3055 of KCC
Red-light
30.1
light source
corporation
fluorescent powder
White-light LED
OE-6336 of Dow
Yellow-light
107.0
light source
Corning
fluorescent powder
Yellow-light LED
OE-6336 of Dow
Yellow-light
77.1
light source
Corning
fluorescent powder
Blue-light LED
OE-6336 of Dow
Yellow-light
8.6
light source
Corning
fluorescent powder
Green-light LED
OE-6336 of Dow
Yellow-light
48.7
light source
Corning
fluorescent powder
Red-light LED
OE-6336 of Dow
Yellow-light
35.8
light source
Corning
fluorescent powder
Control 5
White-light LED
EHA3055 of KCC
Green-light
89.0
light source
corporation
fluorescent powder
Yellow-light LED
EHA3055 of KCC
Green-light
64.2
light source
corporation
fluorescent powder
Blue-light LED
EHA3055 of KCC
Green-light
7.1
light source
corporation
fluorescent powder
Green-light LED
EHA3055 of KCC
Green-light
40.5
light source
corporation
fluorescent powder
Red-light LED
EHA3055 of KCC
Green-light
29.8
light source
corporation
fluorescent powder
White-light LED
OE-6336 of Dow
Blue-light
92.0
light source
Corning
fluorescent powder
Yellow-light LED
OE-6336 of Dow
Blue-light
66.3
light source
Corning
fluorescent powder
Blue-light LED
OE-6336 of Dow
Blue-light
7.4
light source
Corning
fluorescent powder
Green-light LED
OE-6336 of Dow
Blue-light
41.9
light source
Corning
fluorescent powder
Red-light LED
OE-6336 of Dow
Blue-light
30.8
light source
Corning
fluorescent powder
It can be seen from the result of Table I that the use of the LED light source performance compensation apparatus in the implementations of the present invention can effectively regulate the light effect of secondary light of which the wavelength is 380 nm-780 nm and which is emitted by an LED light source with different light colours; and especially for the existing white-light LED light source, degraded products with insufficient light effect in finished white-light LED light sources can be more effectively recycled and dealt with.
Furthermore, compared with the case of not using a light transmissive binding material, the light effects of samples are significantly different when light transmissive binding materials with different performances are used, and the light effect also changes when the approaches of using the light transmissive binding material are different; when the light transmissive binding material is completely filled in the part between the inner surface of the light transmissive supporting member and the LED light source, the light effect is superior to that of partial filling; and after the light wavelength conversion component is used, the function of regulating the light effect can be realized after yellow, red and green luminescent powder is added, wherein the sequence of the magnitude of the light effect is sequentially: adding the yellow luminescent powder, the green luminescent powder and the red luminescent powder.
TABLE II
Light wavelength
Type of light
Light transmissive
conversion
Colour rendering
source
binding material
component
index
Blank control 1
White-light LED
—
—
75.9
light source
Yellow-light LED
—
—
67.3
light source
Blue-light LED
—
—
30.1
light source
Green-light LED
—
—
41.3
light source
Red-light LED
—
—
52.4
light source
Control 2
White-light LED
EHA3055 of KCC
—
76.1
light source
corporation
Yellow-light LED
EHA3055 of KCC
—
67.3
light source
corporation
Blue-light LED
EHA3055 of KCC
—
30.1
light source
corporation
Green-light LED
EHA3055 of KCC
—
41.3
light source
corporation
Red-light LED
EHA3055 of KCC
—
52.4
light source
corporation
White-light LED
OE-6336 of Dow
—
77.2
light source
Corning
Yellow-light LED
OE-6336 of Dow
—
68.2
light source
Corning
Blue-light LED
OE-6336 of Dow
—
30.5
light source
Corning
Green-light LED
OE-6336 of Dow
—
41.9
light source
Corning
Red-light LED
OE-6336 of Dow
—
53.1
light source
Corning
Control 3
White-light LED
EHA3055 of KCC
—
76.2
light source
corporation
Yellow-light LED
EHA3055 of KCC
—
67.3
light source
corporation
Blue-light LED
EHA3055 of KCC
—
30.1
light source
corporation
Green-light LED
EHA3055 of KCC
—
41.3
light source
corporation
Red-light LED
EHA3055 of KCC
—
52.4
light source
corporation
White-light LED
OE-6336 of Dow
—
77.3
light source
Corning
Yellow-light LED
OE-6336 of Dow
—
68.2
light source
Corning
Blue-light LED
OE-6336 of Dow
—
30.5
light source
Corning
Green-light LED
OE-6336 of Dow
—
41.9
light source
Corning
Red-light LED
OE-6336 of Dow
—
53.1
light source
Corning
Control 4
White-light LED
EHA3055 of KCC
Yellow-light
79.1
light source
corporation
fluorescent powder
Yellow-light LED
EHA3055 of KCC
Yellow-light
70.0
light source
corporation
fluorescent powder
Blue-light LED
EHA3055 of KCC
Yellow-light
31.2
light source
corporation
fluorescent powder
Green-light LED
EHA3055 of KCC
Yellow-light
42.9
light source
corporation
fluorescent powder
Red-light LED
EHA3055 of KCC
Yellow-light
54.5
light source
corporation
fluorescent powder
White-light LED
OE-6336 of Dow
Red-light
85.2
light source
Corning
fluorescent powder
Yellow-light LED
OE-6336 of Dow
Red-light
75.3
light source
Corning
fluorescent powder
Blue-light LED
OE-6336 of Dow
Red-light
33.6
light source
Corning
fluorescent powder
Green-light LED
OE-6336 of Dow
Red-light
46.2
light source
Corning
fluorescent powder
Red-light LED
OE-6336 of Dow
Red-light
58.6
light source
Corning
fluorescent powder
Control 5
White-light LED
EHA3055 of KCC
Green-light
81.1
light source
corporation
fluorescent powder
Yellow-light LED
EHA3055 of KCC
Green-light
71.8
light source
corporation
fluorescent powder
Blue-light LED
EHA3055 of KCC
Green-light
32.0
light source
corporation
fluorescent powder
Green-light LED
EHA3055 of KCC
Green-light
44.0
light source
corporation
fluorescent powder
Red-light LED
EHA3055 of KCC
Green-light
55.8
light source
corporation
fluorescent powder
White-light LED
OE-6336 of Dow
Blue-light
83.3
light source
Corning
fluorescent powder
Yellow-light LED
OE-6336 of Dow
Blue-light
73.5
light source
Corning
fluorescent powder
Blue-light LED
OE-6336 of Dow
Blue-light
32.8
light source
Corning
fluorescent powder
Green-light LED
OE-6336 of Dow
Blue-light
45.1
light source
Corning
fluorescent powder
Red-light LED
OE-6336 of Dow
Blue-light
57.2
light source
Corning
fluorescent powder
It can be seen from the result of Table II that the use of the LED light source performance compensation apparatus in the implementations of the present invention can effectively regulate the colour rendering index of secondary light of which the wavelength is 380 nm-780 nm and which is emitted by an LED light source with different light colours; and especially for the existing white-light LED light source, degraded products with insufficient colour rendering indexes in finished white-light LED light sources can be more effectively recycled and dealt with.
Furthermore, compared with the case of not using a light transmissive binding material, the colour rendering indexes of samples are significantly different when light transmissive binding materials with different performances are used, and the colour rendering index also changes when the approaches of using the light transmissive binding material are different; when the light transmissive binding material is completely filled in the part between the inner surface of the light transmissive supporting member and the LED light source, the colour rendering index is superior to that of partial filling; and after the light wavelength conversion component is used, the function of regulating the colour rendering index can be realized after yellow, red and green luminescent powder is added, wherein the sequence of the magnitude of the colour rendering index is sequentially: adding the red luminescent powder, the green luminescent powder and the yellow luminescent powder.
TABLE III
Peak proportion of
blue light and
Light wavelength
yellow light in
Type of light
Light transmissive
conversion
light-emitting
source
binding material
component
spectrum (%)
White-light LED
—
—
104.2
light source
Yellow-light LED
—
—
33.0
light source
Blue-light LED
—
—
321.6
light source
Green-light LED
—
—
62.7
light source
Red-light LED
—
—
76.1
light source
Control 2
White-light LED
EHA3055 of KCC
—
93.0
light source
corporation
Yellow-light LED
EHA3055 of KCC
—
29.5
light source
corporation
Blue-light LED
EHA3055 of KCC
—
287.0
light source
corporation
Green-light LED
EHA3055 of KCC
—
55.9
light source
corporation
Red-light LED
EHA3055 of KCC
—
67.9
light source
corporation
White-light LED
OE-6336 of Dow
—
87.1
light source
Corning
Yellow-light LED
OE-6336 of Dow
—
27.6
light source
Corning
Blue-light LED
OE-6336 of Dow
—
268.8
light source
Corning
Green-light LED
OE-6336 of Dow
—
52.4
light source
Corning
Red-light LED
OE-6336 of Dow
—
63.6
light source
Corning
Control 3
White-light LED
EHA3055 of KCC
—
98.9
light source
corporation
Yellow-light LED
EHA3055 of KCC
—
31.3
light source
corporation
Blue-light LED
EHA3055 of KCC
—
305.2
light source
corporation
Green-light LED
EHA3055 of KCC
—
59.5
light source
corporation
Red-light LED
EHA3055 of KCC
—
72.2
light source
corporation
White-light LED
OE-6336 of Dow
—
87.0
light source
Corning
Yellow-light LED
OE-6336 of Dow
—
29.5
light source
Corning
Blue-light LED
OE-6336 of Dow
—
287.6
light source
Corning
Green-light LED
OE-6336 of Dow
—
56.1
light source
Corning
Red-light LED
OE-6336 of Dow
—
68.1
light source
Corning
Control 4
White-light LED
EHA3055 of KCC
Yellow-light
82.0
light source
corporation
fluorescent powder
Yellow-light LED
EHA3055 of KCC
Yellow-light
11.9
light source
corporation
fluorescent powder
Blue-light LED
EHA3055 of KCC
Yellow-light
295.9
light source
corporation
fluorescent powder
Green-light LED
EHA3055 of KCC
Yellow-light
41.1
light source
corporation
fluorescent powder
Red-light LED
EHA3055 of KCC
Yellow-light
54.3
light source
corporation
fluorescent powder
White-light LED
OE-6336 of Dow
Red-light
76.0
light source
Corning
fluorescent powder
Yellow-light LED
OE-6336 of Dow
Red-light
24.1
light source
Corning
fluorescent powder
Blue-light LED
OE-6336 of Dow
Red-light
234.5
light source
Corning
fluorescent powder
Green-light LED
OE-6336 of Dow
Red-light
45.7
light source
Corning
fluorescent powder
Red-light LED
OE-6336 of Dow
Red-light
55.5
light source
Corning
fluorescent powder
Control 5
White-light LED
EHA3055 of KCC
Green-light
79.9
light source
corporation
fluorescent powder
Yellow-light LED
EHA3055 of KCC
Green-light
25.3
light source
corporation
fluorescent powder
Blue-light LED
EHA3055 of KCC
Green-light
246.6
light source
corporation
fluorescent powder
Green-light LED
EHA3055 of KCC
Green-light
48.1
light source
corporation
fluorescent powder
Red-light LED
EHA3055 of KCC
Green-light
58.3
light source
corporation
fluorescent powder
White-light LED
OE-6336 of Dow
Blue-light
116.8
light source
Corning
fluorescent powder
Yellow-light LED
OE-6336 of Dow
Blue-light
46.7
light source
Corning
fluorescent powder
Blue-light LED
OE-6336 of Dow
Blue-light
330.7
light source
Corning
fluorescent powder
Green-light LED
OE-6336 of Dow
Blue-light
75.9
light source
Corning
fluorescent powder
Red-light LED
OE-6336 of Dow
Blue-light
89.1
light source
Corning
fluorescent powder
It can be seen from the result of Table III that the use of the LED light source performance compensation apparatus in the implementations of the present invention can effectively regulate the proportion of blue light of secondary light of which the wavelength is 380 nm-780 nm and which is emitted by an LED light source with different light colours; and especially for the existing white-light LED light source, degraded products with a defective proportion of blue light in finished white-light LED light sources can be more effectively recycled and dealt with.
Furthermore, compared with the case of not using a light transmissive binding material, a peak proportion of blue light and yellow light is reduced significantly in the spectrum of the sample when light transmissive binding materials with different performances are used, and the peak proportion of blue light and yellow light also changes in the spectrum when the approaches of using the light transmissive binding material are different; when the light transmissive binding material is completely filled in the part between the inner surface of the light transmissive supporting member and the LED light source, the peak proportion of blue light and yellow light is greater than that of partial filling; and after the light wavelength conversion component is used, the function of regulating the proportion of blue light can be realized after yellow, red and green luminescent powder is added, wherein the sequence of the magnitude of the peak proportion of blue light and yellow light is sequentially: adding the yellow luminescent powder, the green luminescent powder and the red luminescent powder.
FIG. 19 shows a parameter measurement diagram when measuring the proportion of blue light in blank control 1 and control 2 and control 3 in the above-mentioned Tables, comprising two particular implementations in blank control 1 and control 2 and control 3.
TABLE IV
Light wavelength
Type of light
Light transmissive
conversion
Colour
source
binding material
component
tolerance
Blank control 1
White-light LED
—
—
6.0
light source
Yellow-light LED
—
—
9.6
light source
Blue-light LED
—
—
12.7
light source
Green-light LED
—
—
11.6
light source
Red-light LED
—
—
10.0
light source
Control 2
White-light LED
EHA3055 of KCC
—
6.2
light source
corporation
Yellow-light LED
EHA3055 of KCC
—
9.9
light source
corporation
Blue-light LED
EHA3055 of KCC
—
13.1
light source
corporation
Green-light LED
EHA3055 of KCC
—
11.9
light source
corporation
Red-light LED
EHA3055 of KCC
—
10.4
light source
corporation
White-light LED
OE-6336 of Dow
—
6.1
light source
Corning
Yellow-light LED
OE-6336 of Dow
—
9.8
light source
Corning
Blue-light LED
OE-6336 of Dow
—
13.0
light source
Corning
Green-light LED
OE-6336 of Dow
—
11.8
light source
Corning
Red-light LED
OE-6336 of Dow
—
10.2
light source
Corning
Control 3
White-light LED
EHA3055 of KCC
—
5.0
light source
corporation
Yellow-light LED
EHA3055 of KCC
—
8.0
light source
corporation
Blue-light LED
EHA3055 of KCC
—
10.6
light source
corporation
Green-light LED
EHA3055 of KCC
—
9.6
light source
corporation
Red-light LED
EHA3055 of KCC
—
8.4
light source
corporation
White-light LED
OE-6336 of Dow
—
5.2
light source
Corning
Yellow-light LED
OE-6336 of Dow
—
8.3
light source
Corning
Blue-light LED
OE-6336 of Dow
—
11.0
light source
Corning
Green-light LED
OE-6336 of Dow
—
10.0
light source
Corning
Red-light LED
OE-6336 of Dow
—
8.7
light source
Corning
Control 4
White-light LED
EHA3055 of KCC
Yellow-light
7.0
light source
corporation
fluorescent powder
Yellow-light LED
EHA3055 of KCC
Yellow-light
11.2
light source
corporation
fluorescent powder
Blue-light LED
EHA3055 of KCC
Yellow-light
14.8
light source
corporation
fluorescent powder
Green-light LED
EHA3055 of KCC
Yellow-light
13.5
light source
corporation
fluorescent powder
Red-light LED
EHA3055 of KCC
Yellow-light
11.7
light source
corporation
fluorescent powder
White-light LED
OE-6336 of Dow
Red-light
4.3
light source
Corning
fluorescent powder
Yellow-light LED
OE-6336 of Dow
Red-light
6.6
light source
Corning
fluorescent powder
Blue-light LED
OE-6336 of Dow
Red-light
8.7
light source
Corning
fluorescent powder
Green-light LED
OE-6336 of Dow
Red-light
7.9
light source
Corning
fluorescent powder
Red-light LED
OE-6336 of Dow
Red-light
6.9
light source
Corning
fluorescent powder
Control 5
White-light LED
EHA3055 of KCC
Green-light
4.2
light source
corporation
fluorescent powder
Yellow-light LED
EHA3055 of KCC
Green-light
6.8
light source
corporation
fluorescent powder
Blue-light LED
EHA3055 of KCC
Green-light
9.0
light source
corporation
fluorescent powder
Green-light LED
EHA3055 of KCC
Green-light
8.2
light source
corporation
fluorescent powder
Red-light LED
EHA3055 of KCC
Green-light
7.1
light source
corporation
fluorescent powder
White-light LED
OE-6336 of Dow
Blue-light
3.0
light source
Corning
fluorescent powder
Yellow-light LED
OE-6336 of Dow
Blue-light
4.8
light source
Corning
fluorescent powder
Blue-light LED
OE-6336 of Dow
Blue-light
6.4
light source
Corning
fluorescent powder
Green-light LED
OE-6336 of Dow
Blue-light
5.8
light source
Corning
fluorescent powder
Red-light LED
OE-6336 of Dow
Blue-light
5.0
light source
Corning
fluorescent powder
It can be seen from the result of Table IV that the use of the LED light source performance compensation apparatus in the implementations of the present invention can effectively regulate the colour tolerance of secondary light of which the wavelength is 380 nm-780 nm and which is emitted by an LED light source with different light colours; and especially for the existing white-light LED light source, degraded products with defective colour tolerance in finished white-light LED light sources can be more effectively recycled and dealt with.
Furthermore, compared with the case of not using a light transmissive binder, the colour tolerance of the sample is slightly reduced when light transmissive binding materials with different performances are used, and the colour tolerance also changes when the approaches of using the light transmissive binder are different; when the light transmissive binder is completely filled in the part between the inner surface of the light transmissive supporting member and the LED light source, the colour tolerance is superior to that of partial filling; and after the light wavelength conversion component is used, the function of regulating the colour tolerance can be realized after yellow, red and green luminescent powder is added, wherein the sequence of numerical magnitude of the colour tolerance is sequentially: adding the yellow luminescent powder, the red luminescent powder and the green luminescent powder.
TABLE V
Light wavelength
Type of light
Light transmissive
conversion
Relevant colour
source
binding material
component
temperature (K)
Blank control 1
White-light LED
—
—
5687.6
light source
Yellow-light LED
—
—
5270.6
light source
Blue-light LED
—
—
6681.9
light source
Green-light LED
—
—
6491.4
light source
Red-light LED
—
—
5102.0
light source
Control 2
White-light LED
EHA3055 of KCC
—
5712.0
light source
corporation
Yellow-light LED
EHA3055 of KCC
—
5293.2
light source
corporation
Blue-light LED
EHA3055 of KCC
—
6710.5
light source
corporation
Green-light LED
EHA3055 of KCC
—
6519.2
light source
corporation
Red-light LED
EHA3055 of KCC
—
5123.8
light source
corporation
White-light LED
OE-6336 of Dow
—
5708.0
light source
Corning
Yellow-light LED
OE-6336 of Dow
—
5289.4
light source
Corning
Blue-light LED
OE-6336 of Dow
—
6705.8
light source
Corning
Green-light LED
OE-6336 of Dow
—
6514.6
light source
Corning
Red-light LED
OE-6336 of Dow
—
5120.2
light source
Corning
Control 3
White-light LED
EHA3055 of KCC
—
5714.0
light source
corporation
Yellow-light LED
EHA3055 of KCC
—
5295.0
light source
corporation
Blue-light LED
EHA3055 of KCC
—
6712.9
light source
corporation
Green-light LED
EHA3055 of KCC
—
6521.5
light source
corporation
Red-light LED
EHA3055 of KCC
—
5125.6
light source
corporation
White-light LED
OE-6336 of Dow
—
5704.0
light source
Corning
Yellow-light LED
OE-6336 of Dow
—
5285.7
light source
Corning
Blue-light LED
OE-6336 of Dow
—
6701.1
light source
Corning
Green-light LED
OE-6336 of Dow
—
6510.1
light source
Corning
Red-light LED
OE-6336 of Dow
—
5116.7
light source
Corning
Control 4
White-light LED
EHA3055 of KCC
Yellow-light
5784.5
light source
corporation
fluorescent powder
Yellow-light LED
EHA3055 of KCC
Yellow-light
5369.9
light source
corporation
fluorescent powder
Blue-light LED
EHA3055 of KCC
Yellow-light
6773.0
light source
corporation
fluorescent powder
Green-light LED
EHA3055 of KCC
Yellow-light
6583.6
light source
corporation
fluorescent powder
Red-light LED
EHA3055 of KCC
Yellow-light
5202.2
light source
corporation
fluorescent powder
White-light LED
OE-6336 of Dow
Red-light
4853.5
light source
Corning
fluorescent powder
Yellow-light LED
OE-6336 of Dow
Red-light
4438.9
light source
Corning
fluorescent powder
Blue-light LED
OE-6336 of Dow
Red-light
5842.0
light source
Corning
fluorescent powder
Green-light LED
OE-6336 of Dow
Red-light
5652.6
light source
Corning
fluorescent powder
Red-light LED
OE-6336 of Dow
Red-light
4271.2
light source
Corning
fluorescent powder
Control 5
White-light LED
EHA3055 of KCC
Green-light
5767.5
light source
corporation
fluorescent powder
Yellow-light LED
EHA3055 of KCC
Green-light
5352.9
light source
corporation
fluorescent powder
Blue-light LED
EHA3055 of KCC
Green-light
6756.0
light source
corporation
fluorescent powder
Green-light LED
EHA3055 of KCC
Green-light
6566.6
light source
corporation
fluorescent powder
Red-light LED
EHA3055 of KCC
Green-light
5185.2
light source
corporation
fluorescent powder
White-light LED
OE-6336 of Dow
Blue-light
5861.5
light source
Corning
fluorescent powder
Yellow-light LED
OE-6336 of Dow
Blue-light
5446.9
light source
Corning
fluorescent powder
Blue-light LED
OE-6336 of Dow
Blue-light
6850.0
light source
Corning
fluorescent powder
Green-light LED
OE-6336 of Dow
Blue-light
6660.6
light source
Corning
fluorescent powder
Red-light LED
OE-6336 of Dow
Blue-light
5279.2
light source
Corning
fluorescent powder
It can be seen from the result of Table V that the use of the LED light source performance compensation apparatus in the implementations of the present invention can effectively regulate the relevant colour temperature of secondary light of which the wavelength is 380 nm-780 nm and which is emitted by an LED light source with different light colours; and especially for the existing white-light LED light source, degraded products with a defective relevant colour temperature in finished white-light LED light sources can be more effectively recycled and dealt with.
Furthermore, compared with the case of not using a light transmissive binder, the relevant colour temperature change insignificantly when light transmissive binding materials with different performances are used, and there is also no great change in the relevant colour temperature when the approaches of using the light transmissive binder are different; when the light transmissive binder is completely or partially filled in the part between the inner surface of the light transmissive supporting member and the LED light source, there is also no significant change in the relevant colour temperature of the sample; and after the light wavelength conversion component is used, the function of regulating the relevant colour temperature can be realized after yellow, red and green luminescent powder is added, wherein the relevant sequence of the magnitude is sequentially: adding the green luminescent powder, the yellow luminescent powder and the red luminescent powder.
In Tables I to V above, the luminescent powder used is as follows: the yellow fluorescent powder is Y-04 available from Intematix, the red fluorescent powder is 0763 available from GRINM, the green fluorescent powder is G2762 available from Intematix, and the blue-green fluorescent powder is LNBG490 available from RoHS.
It can be seen from Tables I to V above that by means of the LED light source performance compensation apparatus of the present invention, the performance parameters of the existing LED light source, especially light emergent from a white-light LED light source, can be effectively regulated, and a corresponding light wavelength conversion component and/or light transmissive binding material can be selected according to different performance regulations in addition to the above-mentioned performance parameters.
The above implementations are only preferred implementations of the present invention, and it should be noted that the above-mentioned preferred implementations should not be deemed as limitations to the present invention, and the protection scope of the present invention shall be subject to the scope defined in the claims. For those skilled in the art, several improvements and decorations can also be made without departing from the spirit and scope of the present invention, and these improvements and decorations shall also be deemed as the protection scope of the present invention. | An LED light source performance compensation apparatus and a white-light LED light-emitting device. The LED light source performance compensation apparatus comprises: a light transmissive supporting member ( 101 ), wherein the light transmissive supporting member ( 101 ) is provided with a light performance parameter regulation member ( 102 ); and after secondary light of which the wavelength is 380 nm-780 nm and which is emitted by an LED light source ( 103 ) passes through the performance compensation apparatus, light performance parameters are adjusted. The LED light source performance compensation apparatus can effectively regulate the light performance parameters of the LED light source, thereby remedying the defects of the secondary light emitted by an existing finished LED light source in terms of light performance parameters. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to an improved wave-damping underwater truss structure, and more particularly to an improved wave-damping underwater truss structure, in which an underwater truss includes a number of diagonal members arranged not parallel with each other and provided with one or more disc-shaped flanges (hereinafter referred to as a brim).
2. Description of the Prior Art
A wave-damping underwater truss structure is a light-weight offshore structure that substitutes for offshore structures such as a caisson breakwater and a tetrapod, whose wave-damping effects are attributable to their weight. This structure was invented by the present applicant so that it can inexpensively cope with weak ground. The principle structure of this wave-damping structure is disclosed in U.S. Pat. No. 3,864,049, and various types of improved structure of the wave-damping structure are disclosed in U.S. Pat. No. 4,074,497, Japanese Patent Publication 63(1988)-247413, Japanese Utility Model No. 1(1989)-180530 and Japanese Unexamined Patent Publication No. 2(1990)-70812.
Shafts and ball members are combined together to constitute a pyramid-shaped basic constitution such as an equilateral triangular pyramid, a square pyramid or the like. The shaft is provided with a brim or brims to increase a contact area per unit volume with which fluids come into contact, whereby the wave-damping capability of the truss structure is improved. This makes it possible to rationalize the entire size and economical efficiency of the structure to a much greater extent. The wave-damping underwater truss structure utilizes the feature wherein when waves pass through the underwater truss structure, the shape of the structure interferes with, and disturbs, the movement of the waves, so that the waves become turbulent and disappear as a result. This structure is characterized in that it serves as a wave-damping structure having a permeability for undulation.
In principle, this wave-damping structure can be expected to yield a considerable wave damping effect by changing undulation to turbulence and swirls. Because of its features, i.e., a relatively light weight, it is desired that this wave-damping underwater truss structure be put into practice. To this end, further advantageous improvements in the wave-damping structure are expected.
In the case of an existing wave-damping underwater truss structure that has been studied and developed up to the present, it is acknowledged that relatively small waves produced in a laboratory, that is, wave components having a high kinetic energy per unit spacing are damped to a significant extent. However, it came to light that such an existing wave-damping structure cannot sufficiently cope with sluggish waves such as "Tsunami", or tidal waves, and swell practically seen in the ocean. The existing wave-damping structure encounters the next problem of further improving the wave damping effect on these sluggish wave. It is considered especially difficult for a permeable wave-damping structure to dampen tsunami (tidal waves). Even a breakwater produced by the conventional gravimetoric method is also costly and technically limited. It is expected that a great depth breakwater having a truss constitution, which is eminently superior to a conventional one in reduced cost and construction period, will cope with the sluggish waves before the tsunami energy is excessively concentrated when the sluggish waves approach the seashore, so that the energy is wasted. In this point, however, this permeable wave-damping structure has an unchanging large permeability to the waves, thereby impairing the entire wave damping effect. For this reason, a drastic solution of such a problem is awaited.
SUMMARY OF THE INVENTION
In view of the foregoing observations and descriptions, the object of this invention is to facilitate the construction of a wave-damping structure and a reduction in the construction period thereof by improving the effective damping of all undulation including sluggish waves and reducing the weight of the structure to a much greater extent, and also to reduce the cost of the structure by saving members, thereby simultaneously resolving all problems.
In other words, the object of this invention is to provide a brimmed wave-damping underwater truss structure that causes the kinetic energy of "Tsunami", swell or the like to be effectively wasted, and which is reduced in weight.
To this end, according to one aspect of this invention, the present invention provides a wave-damping underwater truss structure comprising:
diagonal shaft members;
ball members provided on the vertex of the truss-shaped structure for joining together said diagonal shaft members in the form of a truss; and
one or more brims formed on at least some of said diagonal shaft members, wherein the improvement further comprises
a plurality of openings provided in said brim, said openings having rugged rim or rims.
According to a second aspect of this invention, the present invention provides a brimmed wave-damping underwater truss structure characterized in that
a plurality of openings with rugged rim or rims are formed on a brim.
These openings may be circularly formed like an oval, or rectangularly formed. More rational designing of the opening is effected by selecting the number and shape of the opening in accordance with the location where the structure is installed and also the purpose of that installation.
The rugged rim may be formed on either the front or the rear side of the periphery of the opening or on both sides of the same. Alternatively, irregularities may be formed along the internal circumferential surface of the opening. The cross-sectional view of these irregularities include a number of triangles, and the irregularities should preferably comprise a plurality of acute-angled continuous irregularities or angularities.
The wave-damping underwater truss structure according to this invention includes diagonal shaft member provided with a brim or brims, each having openings with rugged rim or rims, and hence the openings lead to the significant reduction of material used for the brim. The rugged pattern formed around the opening causes a swirl resulting from the disturbance of the brim to be divided into a number of smaller swirls when the swirl passes through that opening. The rate of smaller swirls is increased during the splitting process of eddy motion in a cascade manner. The viscous friction of the swirl promotes the conversion of kinetic energy to heat energy, thereby depleting the kinetic energy. The rim or rims formed around the opening compensate for a reduction in strength of the brim.
In this invention, the openings formed on the brim prevent the occurrence of cavitation which will be caused by a brim without openings, and hence damage to members of the structure can be advantageously suppressed.
The irregularities formed along the rim of the opening in the brim can reduce viscosity resistance of all resistance which the brim offers to a stream in an advantageous manner to a much greater extent, whereby pressure drag is reduced. Such a rugged pattern formed on the surface yields effects similar to those put forward in Japanese Unexamined Patent Publication No. 63(1988)-247413 owned by the present applicant.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view showing a brimmed constitution which is one of basic structures making up an underwater truss structure;
FIG. 2 is a perspective view showing brimmed shafts used with an underwater truss structure according to a first embodiment of this invention;
FIG. 3 is an enlarged perspective view showing an opening shown in FIG. 2;
FIG. 4 is a front view showing a brimmed shaft used with an underwater truss structure according to a second embodiment of this invention;
FIG. 5 is an enlarged perspective view showing an example of irregularities formed along the rim of the opening shown in FIG. 4;
FIG. 6 is an enlarge front view showing another example of irregularities formed along the rim of the opening; and
FIG. 7 is an enlarged perspective view showing details of the configuration of the irregularity formed along the rim of the opening shown in FIG. 6.
DETAILED DESCRIPTION OF THE INVENTION
Referring to the accompanying drawings, embodiments of a wave-damping underwater truss structure according to this invention will now be described.
FIG. 1 is a perspective view showing a brimmed underwater truss structure which is one of the basic structures making up a wave-damping underwater truss structure. This brimmed underwater truss structure is assembled by the combination of six shafts 10, each having at least one brim 30 located at the axial center thereof, with four ball members 20 in such a way that an equilateral triangular pyramid is made up with the ball member 20 positioned at the vertex thereof. FIG. 1 shows the fixed brim 30, but the brim 30 may be resiliently attached to the shaft 10. In addition, the number of brims 30 to be attached to the shaft 10 can be increased.
The resilient attaching of the brim 30 to the shaft 10 is disclosed, in detail, in Japanese Utility Model Publication 1(1989)-180530. For simplicity, openings formed on the brim 30 which are constituent elements of this invention are not shown in FIG. 1.
FIG. 2 is a schematic representation showing a brimmed shaft for use with an underwater truss structure according to a first embodiment of this invention; and FIG. 3 is an enlarged view showing the opening shown in FIG. 2.
As shown in FIG. 2, the brim 30 fixed to the shaft 10 in an integrated fashion or in a separated way is provided with openings 31 having rugged rims (where the term "rugged" is used in its definitional sense of being rough or uneven as opposed to that meaning sturdy or strongly built). These openings are circular or oval in shape, and twelve openings are formed along one brim 30.
The rugged rim may be formed along the periphery of the opening 31, and particularly formed along the inner circumferential surface of the opening 31 as shown in FIGS. 2 and 3. The rugged rim may be formed on either the front or the rear surface of the brim around the opening 31, or may be formed on both sides of the brim.
FIGS. 4, 5, 6 and 7 show an example in which the rugged rim is formed on either the front or the rear surface of the brim along the opening 31 or on both sides of the brim.
FIG. 4 is a front view showing the brim 30. Annular irregularities 31a are formed on the brim surface along the periphery of each of six openings 31. FIG. 5 is an enlarged perspective view showing the irregularities. In the case shown in FIG. 5, the irregularities are formed only on one side of the brim surface, but These irregularities may be formed on both sides of the brim. FIGS. 6 and 7 show an example in which a number of triangular pyramids are formed on both sides of the brim. FIG. 6 is an enlarged front view showing the opening 31, and FIG. 7 is an enlarged perspective view showing the same. In this example, the irregularities are formed on both sides of the brim.
These irregularities include a number of triangles, and should preferably comprise a plurality of acute-angled continuous triangles. FIGS. 6 and 7 show an example of such irregularities. For instance, a number of openings with rugged rims are formed on the surface of a plastic radish grater. These look similar to the example shown in FIG. 7.
The brim 30 having a large diameter is formed at the center in the direction of the axis of the shaft 10. This brim 30 is produced by joining together, for example, two front and rear members having the same shape, and the brim is resiliently attached to the shaft 10 with packing, which is made of a resilient material, being sandwiched between them. Japanese Patent Publication No. 1(1989)-180530 describes the constitution of the joined part between the brim 30 and the shaft 10 in detail.
Several embodiments of the invention have now been described in detail. It is to be noted, however, that these descriptions of specific embodiments are merely illustrative of the principles underlying the inventive concept. It is contemplated that various modifications of the disclosed embodiments, as well as other embodiments of the invention will, without departing from the spirit and scope of the invention, be apparent to persons skilled in the art. | A wave-damping underwater truss structure for simultaneously resolving all problems such as the damping of undulation including sluggish waves and the reduction of weight and cost of members. That truss has a number of brims, each having a plurality of openings with rugged rim or rims. The opening is circularly or rectangularly formed. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application is a continuation of U.S. patent application Ser. No. 13/478,504, filed May 23, 2012, which is a continuation of U.S. patent application Ser. No. 12/182,124, filed Jul. 29, 2008, which is a continuation of U.S. patent application Ser. No. 11/469,953, filed Sep. 5, 2006 and issued as U.S. Pat. No. 7,467,137 on Dec. 16, 2008, which is a continuation of U.S. patent application Ser. No. 10/611,077, filed Jul. 1, 2003 and issued as U.S. Pat. No. 7,103,594 on Sep. 5, 2006, which is a continuation of U.S. patent application Ser. No. 09/974,242, filed Oct. 9, 2001 and issued as U.S. Pat. No. 6,604,103 on Aug. 5, 2003, which is a continuation of U.S. patent application Ser. No. 09/620,651, filed Jul. 20, 2000, which is a continuation of U.S. patent application Ser. No. 09/083,382, filed May 22, 1998, which claims the benefit of the filing date of U.S. Provisional Application No. 60/047,554, filed May 22, 1997, entitled “Document Retrieval System Including Use of Profile Information,” the entire disclosures of which are hereby incorporated herein by reference.
FIELD OF THE INVENTION
The present invention relates to a system for retrieving from a database. More specifically, the present invention improves a system's usability and/or response time so that a user's request to view new information is serviced quickly and/or efficiently.
BACKGROUND AND SUMMARY
The recent proliferation of electronic text and multimedia databases has placed at society's fingertips a wealth of information and knowledge. Typically, a computer is employed that locates and retrieves information from the database in response to a user's input. The requested information is then displayed on the computer's monitor. Modern database systems permit efficient, comprehensive, and convenient access to an infinite variety of documents, publications, periodicals, and newspapers. Yet retrieving information from databases is often slow. Sometimes, this is caused by bandwidth limitations, such as when information is retrieved from remotely-located databases over an ordinary telephone line, a very narrow bottleneck. In other cases, slow retrieval is caused by a relatively slow local mass storage device (e.g., a CD-ROM drive).
There exists a compelling need for a database system that has better usability and/or a quicker response time so that information is displayed very soon after the user requests it. In some embodiments, the present invention takes advantage of the fact that it can be useful to have the user exercise some direct control over the retrieval of information. Some embodiments of the present invention could also take advantage of the fact that the time that the user spends viewing displayed information is often sufficient to advantageously preload a substantial amount of information.
With these and other objects, advantages, and features of the invention that may become hereinafter apparent, the nature of the invention may be more clearly understood by reference to the following detailed description of the invention, the appended claims, and to the several drawings herein.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 a is a block diagram of a general purpose computer.
FIG. 1 b is a diagram of multiple computers connected together to form a network of computers and/or networks.
FIGS. 1 c , 1 d , and 1 g are diagrams illustrating various procedures for installing and executing software.
FIGS. 1 e and 1 f are flow charts illustrating procedures for installing and executing software.
FIG. 2 is a representation of four search documents and three related documents.
FIG. 3 is a representation of four search documents and three related documents with a display view and one anticipated view designated.
FIGS. 4( a ) and 4 ( b ) are each a representation of four search documents and three related documents showing a display view and four anticipated views.
FIGS. 5( a ) and 5 ( b ) are each a representation of four search documents and three related documents showing various term views.
FIG. 6 is a representation of four search documents and three related documents showing various subdocument views.
FIG. 7 shows seven documents ordered according to four different ordering characteristics.
FIGS. 8 , 9 , and 10 are flow charts illustrating alternate embodiments of the present invention.
FIG. 11 is a diagram of the relationships between six statically-related documents.
FIG. 12 is a representation of a video display screen for a computer such as that of FIG. 1 a.
FIGS. 13 a , 13 b , 13 c , 13 d , and 13 e are flow charts illustrating the operation of embodiments of the present invention.
FIG. 14 is a chart illustrating one example of the type of profile information that may be provided in connection with a given document.
FIG. 15 is a flow chart illustrating how profile information can be used in an embodiment of the present invention.
FIG. 16 is a flow chart of the operation of a system in one embodiment of the present invention where a plurality of documents are preloaded in separate threads of execution.
FIGS. 17 a to 17 f are representations of a video display screen illustrating various features and embodiments of the present invention.
FIGS. 18 a and 18 b are flow charts illustrating the operation of various embodiments of the invention.
FIG. 19 is a flow chart illustrating how an embodiment of the present invention can effectively operate in a fee-based environment.
FIGS. 20 a , 20 b , and 20 c are flow charts of the operation of embodiments of the present invention illustrating how server demands can be reduced in some circumstances.
FIG. 21 is a flow chart that illustrates the operation of a computer program illustrating some aspects of the present invention.
FIG. 22 is a flow chart that illustrates the use of an embedded program in connection with the present invention.
FIG. 23 is a network diagram illustrating an alternate method of preloading information on a network.
DETAILED DESCRIPTION
FIG. 1 a is a block diagram of a general purpose computer 102 that can be used to implement the present invention. The computer 102 has a central processing unit (CPU) 104 , memory 113 , and input/output (i/o) circuitry 112 . The CPU 104 is connected to the memory 113 and the i/o circuitry 112 . The i/o circuitry permits the CPU 104 to access various peripheral devices, such as the display or monitor 108 , local storage 106 , and input device(s) 110 . The input device(s) 110 may include a keyboard, mouse, pen, voice-recognition circuitry and/or software, or any other input device. Some type of secondary or mass storage 106 is generally used, and could be, for example, a hard disk or optical drive. The storage 106 can also be eliminated by providing a sufficient amount of memory 113 . Either the storage 106 or the memory 113 could act as a program storage medium that holds instructions or source code. The i/o circuitry 112 is also connected to a network 114 , thereby connecting the computer 102 to other computers or devices.
FIG. 1 b is a representation of multiple computers ( 251 , 252 , 253 , 254 , 255 , 256 , and 257 ) connected together to form a network of computers and/or networks. Computers 251 , 252 , and 256 are shown connected to wide area network (WAN) 263 , whereas computers 253 , 254 , 255 , and 257 are shown interconnected by local area network (LAN) 261 . The LAN 261 is connected to the WAN 263 by connection 262 . Various network resources, such as databases of documents or other objects, are stored on one or more the computers shown in FIG. 1 b.
In a networked environment, such as that of FIG. 1 b , there are numerous ways in which software can be installed, distributed, and/or executed on the various computers on the network. FIG. 1 c illustrates a conventional way in which desktop software is installed and executed. In FIG. 1 c , a computer program 1003 is installed at the computer 1001 through some type of installation program typically started by the user of the computer 1001 , and executed on the computer 1001 . During installation, the program 1003 may need to be configured at the computer 1001 for use with the network in order to enable access to other computers on the network (e.g., 1002 and 1012 ). After installation, the computer program 1003 resides and executes at the computer 1001 , and is persistent. When the computer 1001 is shut down or restarted, the program continues to be stored at the client on non-volatile storage media. Upon restarting the computer 1001 , the program 1003 is available for use without reinstallation.
FIG. 1 d shows a different embodiment. When the network-connected computer 1001 connects to or downloads an object stored on the remote computer 1002 over the network, a program 1005 embedded within the downloaded document or object is installed on the computer 1001 and is executed on the computer 1001 . FIG. 1 e is a flow chart that illustrates one possible installation procedure that is carried out when the computer 1001 accesses the program 1005 .
The computer 1001 identifies at 1020 one or more programs embedded within the accessed object. The client computer then determines whether each embedded program has been installed previously on the computer 1001 . This can be done by searching the computer's storage or system registry for the program or for the program's identifying characteristics. In Microsoft's ActiveX/COM architecture, for example, this is done by searching the registry for an instance of the program's globally unique identifier (GUID) in the system registry.
If the embedded program has been installed on the client computer, the previously installed program is retrieved from local storage at 1030 , and executed at 1028 . However, if the program has not been already installed on the client computer, it is retrieved over the network ( 1023 ), and installed on the client computer. The installation process will typically involve updating a system registry or other persistent storage with identifying information on the computer 1001 .
Preferably the program is installed at 1024 such that it need not be downloaded again over the network when it is encountered embedded within another object. For example, if the computer 1001 were to access an object on computer 1012 that had program 1005 embedded within it, the program 1005 would not need to be installed again because it has already been installed when computer 1002 was accessed.
FIG. 1 f is a flow chart illustrating a different embodiment of the present invention. In this system, when the computer 1001 encounters an object on computer 1002 , it identifies at 1040 each program embedded within the object. It then retrieves one or more programs over the network, and then installs them at the client computer 1001 , but without the use of a persistent storage mechanism. Thus, although the program is executed on the client computer 1001 , the embedded program must be downloaded each time it is encountered because no persistent storage mechanism is used. This type of installation procedure may be more secure, and has been used in some of the early Java implementations.
A system in which software is downloaded over the network, perhaps from an untrusted server, has significant security risks associated with it, and for this reason, security restrictions may be placed on computer programs downloaded from the network. Thus, a downloaded computer program may be unable access some of the resources of a client computer or of the network generally. In some embodiments, however, a downloaded program may be tested for authenticity and safety through a code signing procedure, or through a code verifying procedure. If such a program passes such authenticity tests, it may be given more complete access to system or network resources.
In yet another embodiment, shown in FIG. 1 g , the network-connected computer 1001 connects to the remote computer 1002 over the network, but the program 1021 executes on the remote computer 1002 . Display information and/or instructions are sent from the remote computer 1002 to the computer 1001 , and this information and/or instructions are interpreted by a terminal program or a thin client program 1023 , which updates the display. Input device events (e.g., mouse clicks and keyboard events) caused by the user at the computer 1001 are sent to the remote computer 1002 so as to appropriately alter the execution of the program 1021 executing at the remote computer. In some implementations, it appears to the user of computer 1001 that the program 1021 is executing on computer 1001 , even though the program 1021 is actually executing on the computer 1002 . This scenario, or one similar to it, is employed by some of the thin-client computing environments, such as Citrix Corporation's WinFrame solution, or Microsoft's forthcoming Hydra initiative.
Each of the described techniques for installation and/or use of software can be implemented in connection with the present invention. For example, software used for carrying out one or more embodiments of the present invention may be installed and executed in accordance with the techniques described above.
In FIG. 2 , four documents that might correspond to search documents found as a result of a query are shown. The query may be formulated to find all the documents in a given database that include the phrase “Hadley v. Baxendale.” Each X in the search documents 100 A, 200 A, 300 A, and 400 A represents an occurrence of the phrase “Hadley v. Baxendale.” As can be seen, the phrase “Hadley v. Baxendale” can be found in search document 100 A at two separate locations. Document 200 A has six occurrences, and search document 300 A has three. Search document 400 A has one occurrence—the title of search document 400 A is “Hadley v. Baxendale.”
There are also “related documents” ( 500 A, 600 A, and 700 A) shown in FIG. 2 . A related document is a document that is somehow explicitly associated, linked, or otherwise connected to one of the search documents. For example, if search document 100 A is a judicial opinion, a related document might be a subsequent opinion in the same case (e.g., an decision on appeal). Other related documents might be an opinion or scholarly article that cites or discusses search document 100 A, or a list of judicial opinions that cite the search document. Any document that is usefully associated with the search document can be considered a related document. Often the related document does not satisfy the query, so it is usually not one of the search documents. In some circumstances, however, the related document might satisfy the query, so it can be a search document.
Related documents may also be related only to a particular view within a search document. For example, a search document that is a judicial opinion may have numerous other judicial opinions cited in the text of the opinion. These cited opinions may be “related documents,” but often they relate only to a particular view within the document. Depending on the implementation of the database system, they might not be considered to be “related” to the search document as a whole. Thus, they are available as related documents only when the corresponding cite is within the currently displayed view. In such an implementation, the related documents are dependent on the view shown on the monitor at any given time.
FIG. 3 shows the representation of the four search documents that satisfy the user's query. The search documents are ordered by an ordering characteristic, such as the date of publication. Other ordering characteristics can be used as appropriate for a given situation (e.g., number of query terms in a document, statistical relevance of the documents, type of document, etc.). Any ordering characteristic that permits the search documents to be distinguished from one another can be appropriate. In the example of FIG. 3 , search document 100 A is the first search document according to the ordering characteristic, and view 101 A (shaded) in search document 100 A is the display view shown on the monitor. (The view shown on the monitor at any given time is the “display view.”) Once view 101 A is displayed on the monitor, the user reads, studies or otherwise observes the displayed information. When the user wishes to change the display/view, he or she uses an input device to cause the system to display either (a) a different view in the search document 100 A, or (b) a view from one of the other documents 200 A, 300 A, 400 A, 500 A, 600 A, or 700 A.
The user uses one or more input devices to request particular views. For example, an input device might be a keyboard that includes a “next page” key and a “next document” key. The “next page” key requests the next successive view (view 102 A) within the document currently being viewed (document 100 A). The “next document” view requests the first view (view 201 A) of the next successive search document according to the ordering characteristic (document 200 A). Many database systems have “next page” and “next document” commands or keys (e.g., Westlaw, LEXIS/NEXIS, and West Publishing Company's CD-ROM products), as well as others (e.g., “previous document,” “previous page”). Westlaw also permits a user to request a particular search document or “page” by typing a command. For example, to view search document three ( 300 A), the user types “r3”; to request page 2 (i.e., view 2 ) within the currently displayed document, the user types “p2.” And in some systems, multiple commands can be executed together by separating them with a semicolon, so page two from document three (view 302 A) can be requested with a single command: “r3;p2.”
In the systems of the prior art, when the database system receives the command to display a different view, the requested view must be loaded from the database before it can be displayed on the monitor or display. Since retrieving information from the database is time-consuming, this loading process is undesirably slow. But in a system employing the present invention, the time required to respond to the user's request for a different view (the “requested view”) is reduced by taking advantage of the fact that it is often possible to predict the requested view before the user actually requests it. In the present invention, the view(s) that the user is likely to next request are preloaded while the user is reading the displayed view.
Thus, in one embodiment of the present invention, the view or views (i.e., anticipated view(s)) that are likely to be next requested by the user are “preloaded” (e.g., in the background) to the extent permitted by the time the user spends reading or studying the display view. When the user does request that a different view be displayed (i.e., the user requests a “requested view”), the requested view can be very quickly displayed on the monitor if it has already been preloaded into memory. Thus, if the requested view is one of the anticipated views, the database system is able to quickly respond to the user's request for the requested view.
As shown in FIG. 3 , while the user is reading or studying the display view 101 A, view 201 A is identified as an anticipated view (signified by the arrow from view 101 A to view 201 A). View 201 A is likely to be requested by the user because it is the first view of the “next” search document (as defined by the ordering characteristic) following search document 100 A. And while the display view 101 A is being viewed by the user, the database system will preload view 201 A from the database into memory, before it is actually requested by the user. After view 201 A is preloaded into memory, the input device is checked to see if the user has requested that another view be displayed. If the user has requested that a requested view be displayed, the database system checks to see if the requested view has been loaded into memory (e.g., as the preloaded anticipated view). If the requested view is view 201 A, it will have been loaded into memory as the anticipated view, so view 201 A is retrieved from memory and displayed on the monitor. Since loading the requested view from memory is much faster than loading the requested view from the database, the time required to respond to the user's request for the requested view is shortened dramatically. If the requested view is not in memory, however, it must be retrieved from the database.
Instead of loading the entire anticipated view before checking the input device, in other embodiments of the present invention the input device is monitored during the time the anticipated view is being preloaded into the database. If the user requests a requested view, the preloading of the anticipated view stops and the user's request is serviced. This ensures that the system is very responsive to the user's input. Such an embodiment can be implemented by checking the input device each time a segment (i.e., a portion) of the anticipated view is preloaded. If the computer retrieving information from the database is running a multitasking and/or multithreading operating system, such an embodiment can alternatively be carried out using the various techniques appropriate for such an operating system.
FIG. 4( a ) shows a situation where view 101 A (shaded) is the display view, and the retrieval system has identified four views 102 A, 501 A, 201 A, and 401 A as anticipated views. View 102 A is likely to be requested by the user when the displayed view is view 101 A because it is the next view in the document that the user is currently viewing. View 501 A is a candidate for the requested view because it is the first view from a document ( 500 A) that relates to the search document ( 100 A) that the user is currently viewing. View 401 A is also an anticipated view because the user might wish to view the document that represents the opposite extreme of the ordering characteristic (e.g., the oldest document). And as described above, view 201 A is also likely to be requested by the user.
In the embodiment of FIG. 4( a ), the retrieval system will attempt to load as many of these anticipated views as possible while the user is studying the display view 101 A. If enough time passes before the user requests a requested view, the retrieval system may preload all four of the anticipated views, thereby enhancing the likelihood that the next requested view will be in memory.
Once the user issues a request for a requested view, the requested view is loaded from memory (or from the database, if necessary) and displayed on the monitor. The process of determining and preloading anticipated views then starts over. For example, if the requested view is view 201 A, the display view will then become view 201 A (shaded) as shown in FIG. 4( b ). The anticipated views would also change, and might be identified as indicated by the arrows.
FIG. 5( a ) shows another representation of four search documents showing term views 111 , 112 , 211 , 212 , 213 , 214 , 311 A, 312 A, and 411 . In FIG. 5( a ), a term view is a view that has at least one search term from the query. And as can be seen from document 100 A in FIG. 5( a ), the boundaries of these term views may or may not correspond to the boundaries of views 101 A, 102 A, 103 A, and 104 A. Term views may also be anticipated views because the user might request as a requested view the next view having one or more of the terms in the query. Some systems provide a command for this purpose (e.g., in Westlaw, the command is “t”).
FIG. 5( b ) shows the representation of the four search documents showing other term views 171 , 271 , 272 , 371 , and 471 . These term views are made up of a small number of words surrounding each occurrence of a search term in the search documents. Since the number of words surrounding the search terms is small, more than one set of words can fit on the screen at a given time. Thus, the term view in this embodiment includes information from different parts of the document. The “KWIC” display format in the LEXIS/NEXIS system operates similarly.
FIG. 6 shows another representation of the four search documents showing subdocument views 121 , 122 , 131 , 141 , 221 , 231 , 232 , 233 , 321 , 331 , 421 , 431 , and 441 . The subdocuments are shown in FIG. 6 as 120 , 130 , 140 , 220 , 230 , 240 , 320 A, 330 A, 420 , 430 , and 440 . A subdocument is any logically separable or identifiable portion of a document. For example, if a document is a judicial opinion, there might be subdocuments for the title and citation for the case, for each of the headnotes, for the opinion itself, and for any dissenting opinions. A subdocument view is a view within a subdocument.
Subdocument views may be anticipated views because the user is often particularly interested in a particular portion of the search documents. If the search documents consist of a series of judicial opinions, for example, a user may only wish to view, for each of the search documents, the subdocument for the majority opinion (and not the headnotes, dissenting opinions, etc.). Thus, it may be appropriate for the anticipated views to be drawn primarily from a particular type of subdocument.
In other situations, however, the user may only wish to see the first subdocument view for each subdocument. It would be appropriate in these situations for the anticipated views to be primarily the first views from the various subdocuments within each document.
The retrieval system of the present invention identifies anticipated documents by focussing on the current display view. The current display view gives clues as to which view might be requested by the user because the display view identifies the user's progress in browsing the search documents. In other words, the current display view identifies which search document in the sequence of search documents is currently being viewed. This information is useful because the search document immediately following and preceding the current search document (as defined by the ordering characteristic) is often the search document next requested by the user.
The view displayed just prior to the displayed view might also be a consideration in determining the anticipated views if it tends to show a pattern that can identify the user's next requested view. For example, referring to FIG. 6 , if the user requests view 131 of search document 100 A, and then requests view 231 of search document 200 A, the retrieval system can consider these two consecutive display views and determine that an appropriate anticipated view is view 331 of search document 300 A. View 331 is the first view of subdocument 330 A, which could be the same type as subdocuments 130 and 230 , the two subdocuments previously viewed by the user. Since the goal is to accurately predict the next view, considering the views that the user requested in the past may be helpful if it tends to identify the views that the user will request in the future.
In general, any appropriate adaptive prediction scheme can be used that uses the user's history of requested views (and display views) to accurately determine which views are likely to be next requested by the user. It might be appropriate in some cases to consider many display views in determining appropriate anticipated views. Longer histories may tend to identify patterns that would not show up if only a small number of recent display views are considered.
Tendencies can even be monitored over more than one research session in situations where a particular user or group of users tend to request views in a particular pattern each time research is done. In addition, the user could be prompted to indicate the type of research being undertaken, which may give clues as to what type of anticipated views are appropriate for efficient operation. Finally, the particular databases used or type of research being done can be monitored by the database system and advantageously taken into account in determining anticipated views.
In the preferred embodiments of the present invention, the anticipated views are drawn from both related documents and search documents. A fundamental distinction between related documents and search documents is that related documents are statically-related to the search documents, whereas search documents are dynamically-related to one another. This difference is significant because unlike statically-related documents, no predefined link needs to be set up for search documents. A statically-related document is always associated with a particular document, regardless of the query (the related document is therefore statically-related). The search documents, on the other hand, are related to each other by the query. Since the query changes with each search, the search documents are considered dynamically-related to one another.
Some of the recent CD-ROM products have implemented features such as hyperlinked text, and timeline-linked text (clicking on a timeline item will take the user to a relevant article). See The Top 100 CD-ROMs, PC Magazine, Sep. 14, 1994, p. 115. Links of this nature are static because they always apply and do not depend on any particular query run by the user.
The search documents are ordered by an ordering characteristic as described previously. Thus, when a “next document” is requested, it is assumed that the search document requested by a “next document” command is the search document that is “next” according to the ordering characteristic. If the search documents are ordered by publication date, for example, the “next document” will be interpreted as a request for the search document with the next oldest publication date.
In one embodiment of the present invention, it is possible to make a number of different ordering characteristics available for use by the user in browsing the search documents. For example, FIG. 7 shows seven documents labeled “a” through “g” ordered according to four different ordering characteristics. When the display view is in document “a,” the “next document” command can be a request for four different documents (i.e., “b,” “e,” “f,” or “c”), depending on the particular ordering characteristic used. More than one ordering characteristic must therefore be considered when determining anticipated views if the user is capable of moving to a “next document” in the context of more than one ordering characteristic. This feature can be enabled by an input device command that allows the user to select the desired ordering characteristic.
The present invention is applicable to single-user, multiple-user, and many-user databases, but the present invention is most effective when used in connection with single-user databases. The efficient operation of the invention depends on being able to retrieve data from the database very frequently, perhaps continually. The present invention is quite effective with single-user databases such as those on CD-ROM or other mass storage devices (this might also include a hard drive implementation). In a single-user database, no other demands are being made on the database by the other users, so the database is often idle.
But since a many-user or multiple-user database must be shared among more than one user, such a database will often be receiving simultaneous and continual requests for data. Databases in such a system are rarely idle, so there is little time to preload anticipated views into memory. In such a situation, the present invention will not be as effective in improving the response time to users' requests for requested views. But in many-user or multiple-user database systems where the database is not as busy, the present invention can be effective in reducing response times to users' requests for information.
FIG. 8 is a flow chart of the operation of the database system in one embodiment of the present invention. A system in one embodiment of the present invention begins by executing a query to identify the search documents. This step is carried out by search logic 51 . The remaining steps shown in FIG. 8 (described below) are carried out by retrieval logic 52 .
Both the search logic 51 and the retrieval logic 52 are often software, but need not be. As one skilled in the art will recognize, in a software implementation the search logic 51 and the retrieval logic 52 may or may not be integral or intertwined parts of the same computer program.
As dictated by the retrieval logic 52 , the database system then loads into memory a view from one of the search documents. See FIG. 8 . This first display view is then displayed on the monitor. Normally the user will take a few moments to read or study the display view. During this time, one or more anticipated views are identified. The anticipated views are views that the user is likely to request be displayed on the monitor after the display view.
The database system then begins to preload these anticipated views into memory from the database, while also continually monitoring the input device to determine if the user has issued a request to display a different view (i.e., a “requested view”) on the monitor. Anticipated views are loaded into memory until the user requests a requested view.
When the user does makes such a request, the database system then determines whether the requested view is in memory. The requested view may be in memory because it could have been preloaded into memory as an anticipated view. If the requested view is in memory, the requested view becomes the new display view, and it is displayed on the monitor. But if the requested view is not in memory, the requested view must first be loaded from the database before it can be displayed on the monitor as the display view.
The anticipated views are a function of the display view because the views that the user is likely to request depend to some degree on the view the user is currently reading. In other words, those views that are anticipated views when view 101 A is the display view are not likely to be the same as the anticipated views when view 202 A is the display view. Therefore, as shown in FIG. 8 , the anticipated views are determined each time the display view changes.
When the display view is changed, the anticipated views for the prior display view can remain in memory so that they are available if they are ever requested by the user. But if memory is limited, the anticipated views for the prior display view can be deleted from memory, preferably in an efficient matter (e.g., anticipated views common to both the new display view and the prior display view are not deleted from memory). It is best to delete those views that are not likely to be requested by the user. It may also be appropriate to consider whether a view is likely to become an anticipated view in the future.
FIG. 9 shows a flow chart representing another embodiment of the present invention where anticipated views from prior display views are deleted if memory is full. The views deleted are those that are not anticipated views for the new display view. This will presumably make room for new anticipated views to be preloaded into memory (if not all of the anticipated views are already in memory).
The number of anticipated views for a given display view does not have to be a predetermined or constant number, but rather can vary depending on memory available. Typically, the number of anticipated views for a display view is a trade-off between the amount of memory available and the desired speed of retrieval. In instances where memory is plentiful, where the number of search documents is few, and/or where the search documents are small, it may be possible for all of the search documents to be completely loaded into memory. In such a situation, the number of anticipated views for a given display view could be as high as the total number of views in the search documents. At the other end of the spectrum, there might be only one or two anticipated views for each display view if memory is limited.
Embodiments of the present invention can vary as to how anticipated views are preloaded into memory. In the embodiments of FIGS. 8 and 9 , one anticipated view at a time is preloaded into memory, and the retrieval system does not begin preloading a second anticipated view into memory until the prior anticipated view is completely preloaded into memory. In other embodiments, anticipated views are simultaneously preloaded.
Simultaneous preloading of multiple anticipated views can be done in a number of ways. In a multitasking operating system, for example, an appropriate time-slicing procedure can be used to preload the anticipated views so that they are preloaded simultaneously. In another embodiment, one segment from each anticipated view is preloaded in turn, and the cycle is repeated until all the anticipated views are fully preloaded into memory (or until the user's request for a requested view interrupts the preloading process). A segment is any portion of an anticipated view, such as one or two lines or even a single byte of the anticipated view.
FIG. 10 shows a simple implementation of the simultaneous preload concept, where the database system preloads a segment of a first anticipated view into memory, and then preloads a segment of a second anticipated view into memory. These steps continue until either the user requests a requested view, or both anticipated views are fully preloaded into memory. When the user requests a requested view, the database system checks to see if that requested view is in memory. If the requested view is only partially preloaded into memory, that portion in memory can be written to the monitor and the remaining portion loaded from the database. The response time in this situation will still be better than if the entire requested view has to be loaded from the database.
In another embodiment of the invention, the use of profile information is employed to assist in the selection of views or documents to preload, as illustrated in FIGS. 11-12 , 13 a - 13 e , and 14 - 16 . For example, FIG. 11 is a diagram of the relationships between six objects or documents 301 - 306 . The six documents are linked to each other in the manner shown and hereinafter described. Document 301 contains three links ( 310 , 312 , and 314 ); one to each of the documents 302 , 303 , and 304 . Document 302 contains two links, one link 316 to document 305 , and another link 318 to document 306 . Document 305 contains a link 320 back to document 302 , and document 306 contains a link 322 to document 304 . Each of these documents is stored on a server within a network, and may incorporate or have embedded within it objects stored on other servers. The documents 301 - 306 may be stored on the same server, or may be stored on various computers distributed throughout the network.
FIG. 12 shows a representation of a video display screen 404 for a computer such as that of FIG. 1 . The area 404 represents the area on a screen within which images, text, video, and other types of data or multimedia objects can be displayed and manipulated. On the display 404 shown in FIG. 12 , a number of icons or objects 402 are arranged, along with another type of object, window 406 . The window 406 is a representation of a document retrieval, browsing, and/or viewing program that is used to view information either stored locally on the computer or retrieved over a network. The window 406 has a title area 408 that displays the title of the document being displayed. The title area 408 could also display the location or address of the document being displayed, or also the universal resource locator of the document being displayed. Alternatively, an additional area within the window could be used for displaying the universal resource locator. The contents of the document are shown in displayed within the window 406 in FIG. 12 , but it should be understood that the contents could be displayed in other ways. For example, the contents could be displayed on the entire desktop, or a portion of the desktop. In another embodiment, the contents might be scrolled on the screen, perhaps under other windows. In addition, it should be understood that where a document has only a single view, or is treated as having only a single view, the “document” essentially becomes the same as the “view.” In such a situation, a scroll bar (not shown) may be used to allow a user to effectively expand the size of the display, thereby allowing the user to see the entire document/view.
Shown within the document viewing area of the window 406 in FIG. 12 is the contents of the document 301 from FIG. 11 . The document 301 has been displayed in the window 406 in response to a user query, which might involve a key word search or might involve the user specifying the identity, address, or resource locator of document 301 . The document 301 could be also be displayed within the window 406 in response to the selection of a link in another document (not shown) that points to the document 301 .
FIG. 13 a is flow chart representing the operation of one embodiment of the present invention in which profile information is used to assist in the selection of documents to preload. In FIG. 13 a , the documents 302 and 303 are assumed to be stored on the network on a (preferably) remote database server. At 501 in FIG. 13 a , document 301 is retrieved from the server by a document retrieval program that executes on a client computer, such as, for example, the computer 257 in FIG. 1 b . The document 301 may be stored on any of the other computers shown in FIG. 1 b , including computer 257 . Along with the document 301 , the document retrieval program retrieves profile information that is preferably (but not necessarily) embedded within or is stored with document 301 . The profile information can be used to provide information about document 301 , including information about documents that are related to document 301 , as described below.
At 502 , the document viewing program renders document 301 in the window 406 , as shown in FIG. 12 a . Once document 301 is retrieved, the viewing program begins at 504 retrieving from the network the document 302 . During this time, document 301 continues to be displayed in window 406 , and the user is free to read, scroll through, or otherwise interact with the document 301 shown in the window 406 in FIG. 12 a . Thus, document 302 is retrieved over the network ( 504 ) and stored into the memory or local storage ( 505 ) while the user is viewing document 301 .
After document 302 has been retrieved, if the user has not requested (e.g., through the input device) at 506 that another document be displayed, the document viewing program at 508 retrieves document 303 over the network, and this document is then stored in memory or local storage. The document 301 is still displayed in the window 406 at this point. If the user still has not requested that another document be displayed at 510 , the document 304 is retrieved from the network and stored in memory or local storage by the document viewing program in 512 .
At 514 , the document viewing program in the embodiment of FIG. 13 a stops preloading documents, and waits until the user requests that a new document be displayed. When the user does request that a new document be displayed in the viewing program at 514 , the viewing program determines at 516 whether the requested document is one of the documents that has already been retrieved and stored in local storage. If so, then the locally-stored version of the requested document is retrieved from memory or local storage at 518 . The locally-stored version of the requested document is then checked at 519 to see if it is out of date. If the requested document has content that may change often, it may be that the version of the requested document that is stored in local storage is not sufficiently new and is out of date or “stale.” This condition can be determined by monitoring the amount of time since the document was originally preloaded, or by inspecting the time stamp on the requested document stored on the network and comparing it to the time stamp for the locally-stored version to determine whether the locally-stored version has changed.
If the locally stored version of the requested document at 519 is not out of date, then it is displayed at 524 . If the preloaded version at 519 is out of date, or if the requested document has not been preloaded at all ( 516 ), then the requested document is retrieved over the network and is displayed at 524 .
In another embodiment, the document viewing program may continue preloading additional documents at 512 in FIG. 13 a . For example, the document viewing program could begin to preload the documents that are linked to by the documents that are already preloaded (i.e., documents 302 , 303 , and 304 ). In the set of documents shown in FIG. 11 , this would mean that the document viewing program would download over the network additional documents 305 and 306 . Thus, the present invention need not be limited to the preloading of only a single level of linked documents, but rather, could extend to the preloading of two or more levels.
As described in connection with FIG. 13 a , the document viewing program retrieves over the network documents 302 , 303 , and 304 while the user is viewing document 301 . And as shown in FIG. 13 a , document 302 is preloaded first, followed by document 303 , and then by document 304 . In some embodiments, the document viewing program executing on the client computer in FIG. 13 a uses the profile information to determine the order in which the documents 302 , 303 , and 304 are to be retrieved. In other words, in some embodiments, the database server determines the order in which the document viewing program executing on the client preloads the links within document 301 . This procedure can be quite effective because the database server may have useful information that can help to predict the documents that the user will request be displayed at the client computer. For example, a server that keeps track of the frequency that users select the links within document 301 may find that one or two links are selected very often, whereas other links are selected rarely. The server can use this information to instruct the client as to the most efficient order in which to preload documents.
FIG. 14 is a chart illustrating one example of the type of profile information that could be provided with document 301 at 501 of FIG. 13 a . As shown in FIG. 14 , for each of the documents identified in the profile information, the historical percentage of users that have selected the document are identified. The first three documents ( 302 , 303 , and 304 ) are documents that are linked to by the document 301 as shown in FIGS. 3 and 4 . The fourth document (document 319 ) is not linked to or otherwise related to document 301 , but the profile information nevertheless tells us that 2% of the people request document 319 when document 301 is displayed. Thus, the profile information tells us that document 302 is, historically, the most likely document to be selected. The document viewing program can use this information to ensure that document 302 is preloaded when document 301 has been rendered in the window 406 because at least according to this statistical information, document 302 is likely to be requested by the user who is viewing (or who has at least retrieved) document 301 .
Other data that might be included in the document profile might be the server or database in which each document is stored. This information is shown in FIG. 14 , and identifies the document 302 as being from the server “gaylords.com,” and document 303 as being from the “same” database server, which means the database server from which document 301 has been retrieved. Normally, the profile information of FIG. 14 would be stored in a particular format or data structure, or even as source code, and either embedded within the document 301 , or downloaded by the document viewing program along with the document 301 .
In operation, the server sends to the document viewing program the information of FIG. 14 , and the document viewing program can choose to ignore it, or could choose to act upon it in some way. Thus, the document viewing program in one embodiment engages in some form of interpretation of the profile information and it exercises some control over how the information is used. In another embodiment, however, the profile information could simply consist of a list of documents that the document viewing program uses to select what documents to preload. The list of documents might be ordered so the document viewing program could determine relative priorities among the documents, but the document viewing program may not engage in interpretation of any statistical data or other data sent from the server. Such an embodiment may be implemented by actually programming a program embedded within a document to retrieve certain documents, thus effectively hard-coding the documents that are to be preloaded. Another embodiment may use a program embedded within an object or a document that reads a parameter list and uses the parameter list to select the documents to be preloaded. Where the profile information is not used, some type of predefined procedure could be followed for selecting documents to preload, and this procedure may involve preloading the documents that are linked to by the document 301 (the displayed document).
FIG. 15 is a flow chart which illustrates how the profile information might be used in an embodiment of the present invention. At 594 , the document 301 is retrieved over the network, and at 595 , the profile information for document 301 is retrieved over the network. The profile information is then analyzed at 596 to determine which documents to preload when document 301 is being displayed. At 597 , the profile information is further analyzed to determine the order in which the documents identified at 596 should be preloaded. Thus, in this embodiment, the profile information not only identifies the order in which to preload documents, but also identifies at 596 the documents that are to be preloaded.
FIG. 13 b is a continuation flow chart of FIG. 13 a , where the user has requested that document 302 be displayed. In other words, the requested document at 516 of FIG. 12 a is document 302 . Thus, initially in FIG. 13 b the document 302 and associated profile information associated with document 302 is retrieved at 529 and then displayed at 530 within window 406 . At 532 , the viewing program checks to see if the user has requested that another document be displayed. If not, document 305 , which is linked to by document 302 (see FIGS. 3 and 4 b ), is retrieved from the network and stored in local storage. At 536 , the viewing program checks again to determine whether the user has requested that another document be displayed, and then proceeds to preload document 306 , which is the other document linked to by document 302 . In this particular embodiment, the order in which documents 305 and 306 are preloaded is dictated by the profile information.
When the user does request that a different document be displayed in FIG. 13 b , the viewing program determines at 542 whether the requested document has been already loaded into local storage. If it has been loaded into local storage, the requested document is retrieved from the higher-speed local storage ( 544 ) and the contents of the requested document are analyzed to determine if the information in the preloaded version is out of date ( 545 ). If not, the preloaded version of the document is rendered in the window 406 ( 546 ). Otherwise, the document is retrieved over the network ( 548 ), and then rendered in the window 406 ( 546 ).
FIG. 13 c is a continuation of the flow chart of FIG. 13 b , where the user has requested in FIG. 13 b that document 306 be displayed, and at 579 the document 306 and its profile information is retrieved, and then at 580 of FIG. 13 c , document 306 is displayed. At 582 , the viewing program checks to see if the user has requested that another document be displayed. If not, another document is preloaded into the memory unit or into local storage at 584 . As can be seen in FIG. 11 , document 306 contains only link 322 , which is a link back to document 304 . Thus, at 584 , the document 306 may be preloaded into memory or local storage if it is still in memory from a preloading operation at 538 in FIG. 13 b . If it is in memory, it is not necessary to preload it, so the document viewing program can preload from the network some other document that the user may be likely to request. Such a document could be identified in the profile information for document 306 (as described above), or such a document could be a document that was linked to a previously-viewed document, but wasn't fully preloaded into local memory. For example, if in FIG. 13 a document 303 was not preloaded, this document could be preloaded at 584 because it may, at some point, be requested by the user. Alternatively, the document preloaded at 584 may be one of the bookmarked documents maintained by the document viewing program (e.g., at the client), or a document from some other popular site.
When the user requests a new document, the document viewing program checks at 586 to determine whether the requested document has been preloaded ( 586 ). If it has, the preloaded version is retrieved at 588 and analyzed to determine whether it is out of date at 589 . If the preloaded document is not out of date, it is displayed at 590 . Otherwise, the document is retrieved over the network at 592 , and displayed at 590 .
FIG. 13 d is a partial flow chart in an alternate embodiment of the present invention that can be used to replace 504 in FIG. 13 a . FIG. 13 d illustrates that each document normally contains a number of objects, and in order to retrieve from the network the entire document, each of these embedded objects must be also be retrieved. In the embodiment of FIG. 13 d , document 302 comprises a base document which is retrieved over the network at 550 . The base document 302 contains references to the embedded objects within document 302 . When the base document is retrieved from the network, it is analyzed at 552 to determine the additional embedded objects (if any) that must be retrieved to complete the document. If document 302 has three embedded objects, each is retrieved from the network as shown in FIG. 13 b in succession (steps 554 , 556 , 558 ).
In an alternate embodiment, shown in FIG. 13 e , a separate thread of execution is started for retrieving each of the embedded objects. This embodiment recognizes that it may be more efficient to download the embedded objects simultaneously, rather than one at a time as shown in FIG. 13 d . The embodiment of FIG. 13 d , however, has the advantage that it may be able to completely download at least one of the embedded objects before it is interrupted by a request to display another document. Depending on the implementation of the viewing program, a fully preloaded object may be more useful than a partially-preloaded object. Preloading documents simultaneously may increase the chance of having a large number of partially preloaded objects, and fewer fully-preloaded objects. Thus, where partially-preloaded objects are less useful than fully-preloaded objects, the embodiment of FIG. 13 d may be more efficient than FIG. 13 e . The elimination of field oxide also enables elimination of conventional active area stagger within the array, thus eliminating area consumed by word lines 96 and 99 of the FIG. 25 embodiment. Thus, the 4F lateral expanse consumed by a memory cell of FIG. 25 is capable of being reduced to 3F in the FIG. 26 embodiment (see dashed outline 240 in FIG. 26 ). This results in the area consumed by a single cell of 6F 2 , as compared to the 8F 2 of the FIG. 25 embodiment.
FIG. 16 is flow chart of the operation of a system in which document 301 and its associated profile information is retrieved at 601 , and the document 301 is displayed at 602 . The documents 302 and 303 are then preloaded in two separate threads of execution (steps 604 and 606 ) so that they are retrieved from the network substantially simultaneously. Unlike FIG. 15 , in the embodiment of FIG. 16 the document viewing program does not preload document 304 while document 301 is displayed. The decision not to preload document 304 may be based on the profile information for document 301 retrieved over the network at 601 in FIG. 16 . For example, the profile information could instruct the document retrieval program to not preload document 304 , or the profile information could indicate that the document 304 has been (historically) so rarely selected by other users that the document retrieval program decides not to retrieve document 304 .
A third thread of execution in FIG. 16 ( 610 ) monitors the user's actions (e.g., manipulation of the input device) to determine if the user has requested that a different document be displayed. When the user does request a document at 610 , the system (e.g., the document viewing program) determines ( 612 ) whether the requested document has been at least partially preloaded. Where it has not, the requested document is retrieved over the network at 618 and displayed at 616 .
However, if the requested document has been at least partially preloaded, the preloaded version is checked for staleness at 617 . At 613 the document viewing program determines whether the requested document has been partially or fully preloaded. If the requested document has been fully preloaded, it is retrieved from local storage ( 614 ) and rendered on the display ( 616 ). If it has been only partially preloaded, the partially preloaded version is retrieved from local storage ( 620 ), and any portion not in local storage is retrieved from the network ( 622 ), and then rendered on the display ( 616 ).
In some situations, it may be useful to have the user exercise some direct control over the preloading process. For example, FIG. 17 a shows a screen 704 having a window 706 , which includes a title bar 714 and an area 717 in which to visually render the contents of a document. A cursor 724 corresponding to a pointing-type input device is also shown in the embodiment of FIG. 17 a . The document shown in the window 706 includes hypertext links 718 , 720 , and 722 , and the document also comprises graphical object 707 , which includes area 709 . The graphical object 707 also acts as a link to another document. Also shown in the window 706 are buttons 708 , 710 , and 712 , which each correspond to one of the hypertext links. Button 708 corresponds to link 718 , button 710 corresponds to link 720 , and button 712 corresponds to link 722 .
In FIG. 17 b , the cursor 724 has been moved to the button 712 so that the button 712 is selected. Upon selection, the document viewing program begins preloading the document linked by the “forecast” hyperlink 722 , which corresponds to the button 712 . The “forecast” document is not yet displayed within the window 706 , however, and the “News Items” document shown in FIGS. 17 a and 17 b continues to be displayed. While the document corresponding to link 722 is retrieved over the network, the progress of the preloading operation is displayed on the button 712 . At the point shown in FIG. 17 b , the document corresponding to the “forecast” link is 7% retrieved.
FIG. 18 a is a flow chart illustrating the operation of an embodiment of the present invention that is similar to that described in connection with FIGS. 17 a and 17 b . Initially at 802 , a document is displayed by the document viewing program. The document viewing program then alternatively monitors the user's input to determine whether the user has selected a document to preload ( 804 ) or a document to be displayed ( 808 ). A document is selected to be preloaded by the user when one of the buttons 708 , 710 , or 712 is selected, or when area 709 within the graphical object 707 is selected. Upon such a selection, the document corresponding to the selected button or to the selected graphical object is retrieved over the network and stored in local storage ( 806 ).
In the embodiment of FIG. 17 a , the user requests a document to be displayed by selecting a hypertext link or by selecting the graphical object 707 . When the user has requested a document to be displayed, the viewing program determines at 810 whether the requested document has already been retrieved into local memory or storage. If it has been preloaded, it is retrieved from local storage ( 816 ), and displayed in the window 706 ( 814 ).
In some embodiments, the document may also be checked at 818 to determine whether it is sufficiently new or current. If its download date, modification date, or other information indicates that the contents of the document are not sufficiently new, or are out of date, the requested document is again retrieved over the network at 812 .
FIG. 18 b illustrates an embodiment of the present invention in which a document is displayed at 830 by the viewing program, and then one or more threads of execution begin preloading the documents that are linked to by the displayed document ( 832 ). Another thread of execution monitors the user's input to determine whether the user has selected a link to preload ( 834 ) or whether the user has selected a link to display ( 836 ).
When the user selects a link to preload at 834 , such as by selecting one or more of the buttons 708 , 710 , or 712 in FIG. 17 a , the viewing program begins preloading the selected link, and does so at a higher priority at 840 than any of the other links that are being preloaded at 832 . In other words, when the user selects a link to be preloaded, the viewing program allocates more resources to preloading the selected document at 840 than to any other preloading operations it is carrying out on any other documents at 832 .
Where more than one link has been selected by the user, each could be preloaded at a priority higher than that of the documents being preloaded at 832 . In another embodiment, the document most recently selected for preloading could be given a priority higher than any other, so that the resources of the document viewing program are being applied to the preloading of the most recently selected-document.
Once the user selects a document to be displayed, the viewing program determines at 842 whether the document has been preloaded into local storage. If so, the preloaded version is retrieved from local storage ( 848 ), and displayed ( 846 ). Otherwise, the requested document is retrieved over the network ( 844 ) and displayed ( 846 ).
In the embodiments described in FIGS. 18 a and 18 b , the user selects the document that he or she wishes to preload, and in the embodiments of FIGS. 17 a and 17 b , this is done by selecting button that corresponds to the desired link. In other embodiments, selecting the link that the user wishes to preload can be done in a number of other ways. For example, selection of a link to preload could be carried out by simply passing the mouse or pointing device cursor over the desired link or over an object that corresponds to the link. Such an action could communicate to the document viewing program the link that the user wishes to preload. In another embodiment, the user could select the desired link with a right mouse click (or some other keyboard or pointing device action), or by directing the document viewing program to preload a given link by selecting an appropriate option from a menu that is displayed when the link is selected with the pointing device.
In FIG. 17 a , selection of the document linked to by the graphical object 707 is carried out by the selection of the space 709 within the object 707 , or by passing the cursor over the area 709 in FIG. 17 a . Selection of any other portion of the object 707 constitutes a request that the document corresponding to the document to the object 707 be displayed, rather than preloaded. FIG. 17 b shows one way in which the progress of the preloading can be communicated to the user. FIGS. 17 c , 17 d , 17 e , and 17 f show other embodiments in which the progress being made in the preloading operation is communicated to the user. In FIG. 17 c , the graphical object 707 from FIGS. 17 a and 17 b has been selected for preloading, and a progress gauge 717 has a shaded area 719 which is used to show what portion of the document has been preloaded. When the shaded area 719 fills the gauge 717 entirely, the document linked to by the graphical object 707 has been preloaded.
The button 710 in FIG. 17 d operates in a manner similar to the button 712 of FIG. 17 b , but it changes colors to indicate the progress of the preloading operation. For example, the button 710 could get progressively darker (or lighter) while the linked document is being preloaded. FIG. 17 e shows a text button 760 that is used as a hyperlink. Selection of the button for preloading (e.g., by passing the cursor over the button) causes the button to change color or shade (see FIG. 17 f ) as the preloading proceeds. Any type of visual or audio progress indicator could be used to indicate progress of the preloading, and is useful to the user because he or she will know when a desired document has been preloaded. The user can continue to read or interact with the currently displayed document until the visual or audio indicator signifies that the document has been preloaded. Thus, the user can be assured that when the preloaded document is selected for display, it will be quickly displayed.
In some document retrieval systems, the user may incur a cost for each document or set of information that he or she retrieves from a database or over a network. In such a system, preloading documents before they are requested by the user could incur fees for documents that the user has never intended to see, use, or retrieve from the network. In other words, some documents may be retrieved in such a system simply because they are linked or otherwise related to one of the documents that the user did retrieve. This can undesirably increase costs for the user.
FIG. 19 is a flow chart illustrating how an embodiment of the present invention can effectively operate in an environment where the user incurs fees for each document or set of documents retrieved over the network. In this example, when a document is displayed at 902 , the document viewing program proceeds to preload one or more documents that are linked to the document that the user is viewing. However, the viewing program does not preload the version of the linked documents that incur a fee. Instead, the viewing program preloads a free (or reduced cost) encrypted version of the linked document(s). This encrypted version is distributed free or at a lower charge because it is unreadable (or at least difficult to read) to anyone that attempts to view the encrypted version. However, the encrypted version can be easily converted into the normal, readable version of the content or the document by processing the encrypted version of the document with a password or a key.
When the user selects a document to be displayed at 906 , the viewing program determines at 908 whether an encrypted version of the requested document has been preloaded. If so, the viewing program retrieves the password or key required to decrypt the encrypted version of the document, and at that time, the cost of retrieving the document is incurred at 910 . The encrypted version of the document stored locally is decrypted at 912 and then displayed at 914 .
By retrieving only the password or key over the network and then decrypting the locally-stored encrypted version of the requested document, the document will typically be displayed much more quickly than if the entire document would have to be retrieved from the network. Normally, the size of the key will be much smaller than the size of the document. Retrieving only the key, and processing the encrypted document at the client will therefore typically be much faster than retrieving the unencrypted version of the document over the network upon receiving a request for it.
The use of the procedures described herein may, in some environments, substantially increase the number of requests that are issued to network servers, and may also increase the amount of bandwidth required for a given network. This can be exacerbated where each document has embedded within it additional objects that must be separately requested from the server. Thus, it may be desirable to implement techniques to alleviate, eliminate, or avoid these effects. In one embodiment of the present invention, each time a request is issued to a network server, additional information is included within the request so that the database server (or any other network hardware or resources) is notified of the type of the request. This will allow requests to be prioritized so that server and/or other network resources are not allocated to tasks that may have less priority (e.g., a request to preload a document) than other tasks (e.g., a normal document request).
FIG. 20 a is a flow chart of a system in which the document viewing program communicates to the database server (or to the network itself) a priority for each request. At 1102 , the document viewing program issues a normal priority request to the database server for document A. The database server responds to this request, and at 1104 , document A is retrieved over the network by the document viewing program. When it is received, it is displayed by the document viewing program at 1106 .
The document viewing program then starts a thread that monitors the user input at 1108 to determine whether the user has requested a document for display. Another thread is also started, and this thread at 1120 issues a low priority request to the server for document B (one of the documents it seeks to preload). The user at this point has not requested that document B be displayed, so the retrieval of document B is done based on the expectation that the user may wish to view document B at some point. For this reason, the request for document B is issued on a low-priority basis. (Document B may be a document that is linked to document A, that is identified in profile information, or that is otherwise related to document A.) When the server responds to the request, document B is downloaded over the network at 1122 , and stored locally at 1124 .
The low-priority request allows the network server to respond to other normal or high priority requests in advance of responding to the low-priority request for document B. This can be used to ensure that when the user actually requests a document from the server, the server will service that request before other low-priority requests by either that user or by other users. This information can also be used by the network hardware (e.g., network routers) itself to prioritize the routing of the requests or the routing of packets of data.
When a request that a document be displayed is made by the user at 1108 , the document viewing program determines whether the requested document is in local storage at 1110 . If it is, it is retrieved from local storage at 1116 , and displayed at 1118 . However, if the requested document is not stored in local storage, a normal-priority request is issued to the server at 1112 . The request is a “normal” priority request because the user has actually requested a document, in contrast to the request made at 1120 of FIG. 20 a . The document is then retrieved over the network at 1114 , and then displayed at 1118 .
FIG. 20 b is another embodiment of the present invention that deals generally with the types of problems addressed in FIG. 20 a . After document A is displayed at 1130 , a thread that monitors whether the user has requested a document for display is started at 1132 . Another thread is started at 1140 to determine whether the server on which document B is stored is busy. If it is, a wait state is entered at 1141 so that requests are not issued to the server over the network. This procedure thus preserves network and/or server resources. After a period of time, the server is then checked again. When the server is not busy, document B is retrieved over the network at 1142 , and stored on the client computer at 1144 .
When the user requests a document for display, the document viewing program determines whether the requested document has already been preloaded. If necessary, the requested document is retrieved over the network at 1136 ; otherwise, it is retrieved from local storage at 1140 . After it is retrieved, it is displayed at 1138 .
FIG. 20 c is a flow chart of an embodiment of the present invention in which an anticipated document, document B, is stored in a file along with the objects that are embedded within the document B, are referenced by the document B, or are linked to by document B. By downloading such a file, the number of requests that must be issued to the server can be reduced. And if data compression is used to reduce the size of the file at the server and decompress the file at the client, the number of bits that must be downloaded to the client computer can be reduced.
Once document A is displayed at 1148 in FIG. 20 c , the document viewing program monitors the user at 1150 for a request to display a new document. At the same time (i.e., in another thread of execution), an object that contains document B and the objects embedded within it is retrieved over the network at 1160 . This object may also include one or more documents that are linked to by document B. When the object is downloaded, it is parsed at the client computer at 1162 so as to extract document B and the embedded objects, which are then stored at 1164 on the client computer. When the user requests a document for display, the document viewing program determines at 1152 whether the requested document has already been preloaded. If necessary, requested document is retrieved over the network ( 1154 ), but if possible, it is retrieved from local storage ( 1156 ). After it is retrieved, it is displayed at 1158 .
The present invention is suitable for implementation as an ActiveX or Java control, which could be downloaded as part of a web page into a browser or an operating system for execution on a client computer. In such an embodiment, there may be security restrictions placed on the downloaded control. Appendix A is an outline of a Java program or psuedocode for applet written in Java that can be inserted into a web page, and appears on the web page as a button that it is associated with an HTML link. When the button is selected, the document corresponding to the associated link is preloaded onto the client, and the base HTML document and at least some of the embedded objects are stored on the client's local file storage system. The client's file system is typically much faster than the network.
In some Java environments, the client's local file system is not accessible because of security restrictions if the applet is downloaded from a remote host. These security restrictions can be avoided by using an insecure environment, or by using a code signing technique that allows the user to verify the author of the applet. Once the code is identified as being written by a trusted author, the security restrictions can be safely eased or eliminated.
In another embodiment, a secure means of accessing the client's file system can be used to securely and safely store data on the client's file system. In such a system, the applet may only be allowed to write files to certain directories. The applet may also be limited to reading only files that it had created. One such secure file system for Java has been referred to as “protected domains,” and can be useful in implementing some embodiments of the present invention.
Appendix B is another listing of Java code/psuedocode in an implementation of the computer program or applet that does not use the local file system for storing preloaded documents. Instead, the Java program in Appendix B stores preloaded documents in memory, and implements a web server on the client to serve the documents back to the document viewing program running on the client. Thus, when the user selects a link, the link is redirected to the server running on the client, and that local server responds with the preloaded document if it is available. The document viewing program would, in effect, be retrieving preloaded documents from local memory, thereby making access to preloaded documents quite fast. Such an implementation may also avoid the security restrictions placed on accesses to the local file system in some embodiments.
FIG. 21 is a flow chart that illustrates the high-level operation of the pseudocode of Appendix B. At 1202 , a document is displayed, and a local document or object server is then set up at 1204 . Two threads of execution are started, one to retrieve an anticipated document (document B) from the network and store it as a document capable of being served by the local server (steps 1220 and 1221 ), and another to monitor the user's actions to determine when the user has selected a document for display ( 1204 ).
When the user selects a document for display at 1206 , the request is routed to the local server ( 1210 ) if the requested document had been stored locally. Otherwise, the a request for the document requested by the user is issued to the server (usually a remote server) on the network ( 1216 ). When the document is retrieved (or as it is retrieved), the document is displayed at 1214 .
Because a web page control may have to be downloaded with each page, it may be desirable to implement techniques to speed the amount of time that a user has to wait for a document to be retrieved from the network. One such procedure is to embed a small applet into the web page that is downloaded by the user, where the small applet then retrieves a larger program that carries out the remaining steps. Such a procedure will allow the user to begin interacting with the web page after the small applet is downloaded, and will not require that the user wait for a larger program to be downloaded before interacting with the web page. Once the small applet is downloaded, the larger applet is downloaded in the background while the user is viewing or interacting with the web page.
FIG. 22 is a flow chart that illustrates the use of a small embedded program that retrieves a larger embedded program, and causes the latter to execute. At 1302 , a document or object with an embedded initializing program stored within it is downloaded from the network. The document (or object) is displayed on the screen at 1304 , and in a separate thread of execution, the initializing program is started at 1316 . The initializing program retrieves supplemental program code over the network, and execution of this code is started at 1320 . As indicated in FIG. 22 , this new code retrieves anticipated documents over the network, also at 1320 .
Because the initializing program is small, it takes relatively little time to download, and the document viewing program is able to promptly start the execution of the initializing program. This may allow the display of the document at 1304 to take place more quickly. The effect is a more responsive program that does not cause the user significant delay while an applet implementing the present invention is being downloaded.
Many embodiments of the present invention have been described as storing preloaded documents into local storage at the client computer. However, the present invention need not be limited to contexts in which information is stored at the client computer or in local storage at the client computer. The present invention is useful in any environment where it is possible to store preloaded information in an area where access to the preloaded information is faster than that of the original location for the information. For example, FIG. 23 shows a network where computer 1401 is preloading ( 1412 ) a document 1440 on server 1402 while viewing another document on the network. In the embodiments described previously, the document 1440 is retrieved over the network and stored in local storage at the computer 1401 . However, other embodiments of the present invention can be performed by storing the preloaded document elsewhere, but still in a location that can be accessed quickly.
An example is shown in FIG. 23 where the computer 1401 retrieves document 1440 from the server 1402 as part of a preloading procedure. At the direction ( 1412 ) of computer 1401 , the preloaded document is retrieved ( 1410 ) and stored in the computer 1403 , which is accessible by the computer 1401 over the LAN. Information on computer 1403 can be accessed by the computer 1401 quickly because these two computers are connected over a relatively fast (local) network. This is unlike the connection between the computers 1401 and 1402 , which are connected over the lower speed WAN.
When the preloaded document 1440 is stored on the computer 1403 , it can be more quickly retrieved from computer 1403 than from computer 1410 . Thus, significant enhancements to the responsiveness of the document viewing program can be made in the present invention, even if the preloaded documents or objects are not stored directly in local storage, but instead, are stored elsewhere where they can be retrieved quickly.
Some embodiments of the present invention have been described in the context of accessing the database and identifying search documents through a search term query. The present invention can be applicable in other research-related contexts where search documents are identified using another type of entry path. For example, a time-line can be used for locating information or documents that are associated with a given time or time-frame. Another information access method uses a topic tree that permits a user to choose from successively narrowing topics until the desired topic is located. It is possible for the present invention to be applicable even in other non-research contexts where similar preloading techniques may permit efficient navigation of information and/or short response times. The present invention can also be used in combination with caching systems where previously-displayed documents or views are stored for repeated use.
The present invention has been primarily described in the context of a general purpose computer implementation. As one skilled in the art will recognize, however, it is possible to construct a specialized machine that can carry out the present invention.
The additional references listed below are hereby fully incorporated by reference to the extent that they enable, provide support for, provide a background for, or teach methodology, techniques, and/or procedures employed herein.
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Although the present invention has been shown and described with respect to preferred embodiments, various changes and modifications, even if not shown or specifically described herein, are deemed to lie within the spirit and scope of the invention and the following claims. Any specific features or aspects of the embodiments described or illustrated herein are not intended to limit the scope and interpretation of the claims in a manner not explicitly required by the claims. | An improved information retrieval system is provided that uses profile information indicating one or more possible destinations associated with a web page to assist in preloading. In one aspect, in response to detecting that the user has interacted with a display element in a first web page browser window, the system retrieves information from a second web page before the user requests that the second web page be displayed within the web browser window. This retrieval enables rapid access to various features of web pages in the web browser window. | 6 |
FIELD OF THE INVENTION
The present invention relates to maneuvering apparatus comprising a maneuvering lever and a maneuvering console and provided with at least one pivot hinge by means of which the lever is articulated relative to the maneuvering console for switching between a number of maneuvering positions intended to be converted to corresponding operational states of a device which is to be maneuvered.
BACKGROUND OF THE INVENTION
For a general type of maneuvering apparatus, namely gear controls for motor vehicles, there are a number of known arrangements. These are generally designed in principle for a specific movement pattern, such as, for example, the gear controls for manual gearboxes or for automatic transmissions.
The object of the present invention is to provide a basic design for such maneuvering apparatus which can be used for several different types of maneuvering applications and movement patterns.
SUMMARY OF THE INVENTION
In accordance with the present invention, this and other objects have now been realized by the invention of apparatus for the control of the operational states of a device comprising a maneuvering console including a maneuvering lever, a pivot hinge for the maneuvering lever whereby the maneuvering lever can be actuated into a plurality of positions corresponding to the operational states of the device, the pivot hinge being mounted to permit pivoting of the maneuvering lever with respect to the maneuvering console about an unlimited number of spatial pivot axes, a plurality of controllable units mechanically coupled to the maneuvering lever for selectively limiting the pivoting movement of the maneuvering lever, a plurality of sensors for detecting a maneuvering force applied to the maneuvering lever and the position of the maneuvering lever, whereby the pivoting movement of the maneuvering lever can be selectively limited by the plurality of controllable units based on the detections, and a controller for controlling the plurality of controllable units thereby permitting selected movement of the maneuvering lever based on control conditions set by the controller. In a preferred embodiment, the plurality of controllable units comprises at least two hydraulic pistons and cylinders, a first hydraulic line connecting the at least two hydraulic pistons and cylinders and a first flow limiter disposed in the first hydraulic line, the maneuvering lever being mechanically coupled to each of the at least two hydraulic pistons and cylinders, whereby the pivoting movement of the maneuvering lever is converted into reciprocal movement of the hydraulic pistons within the cylinders. In accordance with a preferred embodiment, the plurality of controllable units comprises four hydraulic pistons and cylinders, and includes a second hydraulic line connecting at least two other of the hydraulic pistons and cylinders, a second flow limiter disposed in the second hydraulic line, and a joint cross for mechanically coupling the maneuvering lever to the four hydraulic pistons and cylinders, the joint cross being mounted with respect to the maneuvering console for pivoting about a pair of pivot axes set at right angles with respect to each other.
In accordance with a preferred embodiment of the apparatus of the present invention, the plurality of sensors includes a plurality of position sensors for detecting the position of the maneuvering lever and a plurality of pressure sensors for detecting the hydraulic pressure in the first and second hydraulic lines on both sides of the first and second flow limiters.
In accordance with another embodiment of the apparatus of the present invention, the apparatus includes a plurality of hydraulic control cylinders coupled in parallel to each other and connected to the first hydraulic line, and a pair of spring-loaded control pistons disposed within the pair of hydraulic control cylinders in opposite directions, whereby the maneuvering lever can be switched between a first mode and a second mode wherein the maneuvering lever can be automatically set to a neutral position.
The objects of the present invention can be achieved by means of a maneuvering apparatus, which includes a pivot hinge arranged to permit pivoting of the maneuvering lever relative to the maneuvering console about an unlimited number of spatial pivot axes, and in which the maneuvering apparatus comprises, on the one hand, a number of controllable devices which are mechanically coupled to the maneuvering lever and which limit the pivoting movement of the maneuvering lever, and, on the other hand, a number of sensor members arranged to detect a maneuvering force initiated on the lever and a maneuvering position of the lever and to control the devices so as to permit a selected movement as a function of control conditions established by means of a control unit.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will be more readily understood with reference to the following detailed description which, in turn, refers to the attached drawings, in which:
FIG. 1 is a diagrammatic representation of one embodiment of the maneuvering apparatus according to the present invention;
FIG. 2 is a diagrammatic representation of the embodiment of the maneuvering apparatus shown in FIG. 1 in a different position;
FIG. 3 is a diagrammatic representation of the embodiment of the maneuvering apparatus shown in FIG. 1 in yet a different position;
FIG. 4 is a front, perspective view of one embodiment of the maneuvering apparatus of the present invention;
FIG. 5 is a front, perspective view of the embodiment of the maneuvering apparatus shown in FIG. 4 in a different position;
FIG. 6 is a top, elevational view of the embodiment of the maneuvering apparatus of the present invention shown in FIG. 4;
FIG. 7 is a front, perspective, partially cut-away exploded view of the embodiment of the maneuvering apparatus of the present invention shown in FIG. 4;
FIG. 8 is a top, elevational view of the lower portion of the embodiment of the maneuvering apparatus shown in FIG. 7; and
FIG. 9 are diagrammatical representations of four different movement patterns which can be achieved using the maneuvering apparatus of the present invention.
DETAILED DESCRIPTION
The underlying concept on which the present invention is based is that the maneuvering lever included in the maneuvering apparatus is mounted freely in the maneuvering apparatus by a pivot hinge which is of a type such that the lever can be allowed to pivot in an unlimited number of directions, i.e. about an unlimited number of pivot axes, but is limited by movement-limiting devices which are controllable, on the one hand, by means of a number of sensor members and, on the other hand, in accordance with an established movement pattern. These sensor members are arranged to detect a maneuvering force initiated on the lever and the position of the lever, and to control the movement-limiting devices in such a way that the selected movement is permitted.
FIGS. 1-3 thus show an example of an application of the principle according to the present invention, in which the movement-limiting devices are a hydraulic system with hydraulic/piston cylinders as the movement-limiting devices. The maneuvering apparatus comprises, in a known manner, a maneuvering lever 1 which in the figure is shown diagrammatically from two directions, i.e. the two levers shown in the same figure are thus one and the same lever as viewed from two directions at right angles to each other. This is done in order to better illustrate the two directions in which the maneuvering lever in the embodiment shown therein is allowed to move under certain conditions upon application of the maneuvering apparatus as a gear control for an automatic transmission of a motor vehicle. These two main directions are the so-called shift direction for shifting the gear lever between different gear change stages, shown by double arrow 2 , and the so-called select direction for selecting between different gear change types, represented by double arrow 3 .
The gear lever has, in a conventional manner, a lever head generally denoted as a lever knob 4 , intended to be gripped by the maneuvering person, i.e. the driver, in order to move the lever part 5 of the lever in the desired direction so as to obtain the desired function, i.e. the desired gear change position, in an arrangement which is maneuvered by the maneuvering apparatus, in this case the gearbox. The maneuvering lever 1 is mounted relative to the vehicle by means of a pivot hinge 6 which, in the example shown, is of the cardan suspension type with two axles set transverse to each other and arranged so that the hinge as such permits free pivoting movement of the gear lever in an unlimited number of directions or movement planes. Its practical construction will be described in more detail hereinbelow. The maneuvering lever 1 is thus rigidly connected to two lifting arms, 7 and 8 , crosslaid at right angles and arranged, in the event of a pivoting movement of the maneuvering lever, to generate forward and backward movements of the piston rods, 9 , 10 , 11 , and 12 , in a number of hydraulic piston cylinders, 13 , 14 , 15 , and 16 , or alternatively to limit or block pivoting movements of the lever. For this purpose, the piston cylinders 13 - 16 are in communication with each other in pairs by means of two hydraulically separate hydraulics systems, more precisely in such a way that the cylinder chamber 17 in the piston cylinder 13 is arranged to be in communication with the cylinder chamber 18 through hydraulic line 19 , while the cylinder chamber 20 is arranged to be in communication with the cylinder chamber 20 ′ by means of a hydraulic line 21 . The cylinder chambers, 17 and 18 and 20 and 20 ′, respectively, are identical pairs, so that one and the same volume of hydraulic fluid is transported in the closed hydraulics system between the two chambers according to the position of the respective pistons, 22 , 23 , 24 , and 25 , in the piston cylinders.
In the communication line, 19 and 21 , between the piston cylinders, 13 , 14 , 15 , and 16 , of each pair there is arranged, according to the present invention, a flow-limiting or blocking member, 26 and 27 , i.e. a valve which is electrically controlled, for example a solenoid valve. This is advantageously intended not only for on/off regulation, but also to be controlled stepwise, i.e. in analog fashion, or in small steps, in which analog or digital control can be used.
The system includes an electrical control unit 28 in the form of a computer which is arranged to control the two valves, 26 and 27 , by means of their respective control output, 29 and 30 , as a function of incoming control signals at a number of inputs to the control unit.
According to the present invention, a number of sensors are included which are arranged to detect the maneuvering person applying a force on the maneuvering lever 1 in a certain direction in order to control the system such that this selected movement can be allowed if it lies within a programmed, established movement pattern. In the example shown, this is achieved by means of a number of pressure sensors which, in the example shown, consist of two pressure sensors, 31 and 32 , for the hydraulics system for shift movements and two pressure sensors, 33 and 34 , for the hydraulics system for select movements. The pressure sensors are situated on both sides of associated flow limiters, 26 and 27 , and are arranged to detect the maneuvering force in the lever 1 in a certain direction by detecting the pressure in the respective hydraulic line, 19 and 21 , as a function of the state of the flow limiters. The control unit 28 has an input, 35 and 36 , for each sensor and controls the valves, 26 and 27 , so that the selected movement is permitted with the above-mentioned proviso, namely on condition that it lies within the established movement pattern. A further condition for permitting movement of the lever is an approved position. This is detected by position sensors which are described in more detail hereinbelow. A further control input 37 leads to the control unit 28 from a switch 38 arranged in the maneuvering lever knob 4 , which switch 38 represents a lock that can be released by the driver, for example a lock for locking against unintentional movements in a certain direction. The established movement pattern is input as a control program in the control unit 28 , which controls the flow limiters, 26 and 27 , and thereby the movements of the lever.
In the example shown, an alternative maneuvering function is included, in which the maneuvering lever can be permitted to spring back to a certain position, which represents a netrual position, from a movement forwards or backwards in the example shown in the shift direction, according to the double arrow 2 . This is acheived by means of the hydraulics system comprising two parallel circuits, 39 and 40 , each of which has double-acting piston/cylinders, 41 and 42 . These each have a piston 44 which is spring-loaded by a compression spring 45 in mutually opposite directions and which divides the cylinder into two chambers, 43 and 46 . These two parallel circuits can be coupled in simultaneously by means of a valve 47 which is closed when changing gear according to the ordinary gear change type, but which is switched to the open position by means of a signal from the control unit 28 which, for example, can be activated by a switch, at the same time as the valve 26 is closed.
In the alternative maneuvering function or maneuvering mode, when the lever 5 is situated in the neutral position, as is shown in FIG. 1, the two pistons 44 in the piston cylinders, 41 and 42 , are prestressed towards their end positions by their respective springs 45 . When the lever 5 is pushed forwards by the person maneuvering it (see FIG. 2 ), the piston 22 is pressed downwards, whereupon hydraulic fluid is forced through line 39 into the cylinder 41 and displaces the piston 44 counter to the action of the spring 45 . By way of position sensor 48 , a position signal is sent to the control unit 28 concerning the position of the lever 1 for a control command to the gearbox to change up a gear for each swing movement. The spring returns the piston to its starting position and thus the lever to the neutral position as soon as the maneuvering force on the lever ceases.
With the piston in its end position in the second piston cylinder 42 , the flow in the associated hydraulic line 40 is blocked until the lever 5 is moved from the neutral position backwards to the position shown in FIG. 3 for changing down gear. In this case, the piston 44 in the piston cylinder 42 is instead displaced counter to the action of its spring 45 , and the control unit 28 receives a position signal from the position sensor 48 which in turn gives a control command to the gearbox for changing down.
In order to create distinct maneuvering positions for the lever 1 , the control unit 28 can be pre-programmed for controlling the valve or valves, 26 and 27 , as a function of the lever position, not only for controlling the movement direction. For example, it is possible to create force thresholds for movements between all positions, and in addition higher force thresholds between certain positions, for example for a reverse position, for creating distinct lever positions and avoiding unintentional movements.
The system described above thus has the purpose of controlling the maneuvering movements of the gear lever, which is mechanically mounted in its pivot hinge 6 for an unlimited number of movement directions. For controlling the lever and the gearbox, the arrangement is thus provided with the position sensors, 48 and 49 , which consist, for example, of angle sensors on the maneuvering lever 1 , in the example shown one sensor for each movement direction. The information on the position of the lever in the selected movement pattern is fed to the inputs 50 of the control unit, which at its main output 51 emits control instructions to, on the one hand, the flow limiters, 26 , 27 and 47 , and, on the other hand, the gearbox for gear changing, suitably by means of the main computer of the vehicle.
FIGS. 4-8 show an example of a practical design of the maneuvering apparatus according to the present invention. It will be seen therefrom that the maneuvering lever 1 of the maneuvering apparatus is mounted with respect to the pivot hinge 6 so as to pivot in a maneuvering console 52 which bears the piston cylinders 13 - 16 . These are arranged with their cylinders 53 in the console and are coupled to the lifting arms, 7 and 8 , by means of their piston rods 9 - 12 . In the example shown, the pivot hinge 6 is mechanically designed as a joint cross with the lever 1 pivotably mounted about a first axle 56 , which is in turn pivotably suspended in a transverse axle 57 mounted in two console arms, 54 and 55 , in the maneuvering console 52 . The position sensors, 48 and 49 , are arranged on the two crosslaid axles of the pivot hinge 6 . The flow limiters, 26 , 27 and 47 , are mounted on one of the two console arms, 54 and 55 .
As is illustrated in FIG. 7, a portion of the joint cross is shown cut away for the sake of clarity so that, as shown in FIG. 8, the geometric configuration is clearer. It can thus be seen that the shift direction 2 and the select direction 3 extend at 45° angles relative to the two pivot axles, 56 and 57 , of the pivot hinge 6 . It will be appreciated that in this example the lifting arms, 7 and 8 , are represented by diagonally situated arm portions, 7 ′, 7 ″, 8 ′, and 8 ″, in the joint cross.
As is illustrated in FIG. 9, the arrangement according to the present invention can be used to create an unlimited number of movement patterns by programming the control unit 28 within an outer frame of movement which is shown diagrammatically in the figure by a margin line 58 around each illustrated pattern. The movement pattern can, for example, have a step ladder shape with, therefore, gear changing between shift and select movements for each gear change position including a special position for the alternative gear change type with spring return to a neutral position M from a plus position with changing up for each lever movement and a minus position for changing down for each lever movement. Alternatively, the movement pattern can have essentially an L shape, with addition of the special spring return movement or, as in manual gearboxes, a pattern similar to a double H, or alternatively a completely rectilinear movement pattern. The movement pattern does not have to be rectilinear, but instead curved movement patterns are also possible by means of controlling the flow limiters.
In the case of a maneuvering apparatus programmed for a movement pattern with an L shape, see FIG. 9, i.e. a rectilinear shift movement in a first gear change mode and a laterally directed select movement for a second mode, the following takes place. When the lever 1 is situated in the N position (neutral position) and is not activated by any maneuvering force, all of the flow limiters, 26 , 27 and 47 , are closed. A maneuvering force in the direction towards the R position (reverse) which is detected by the pressure sensors, 31 and 32 , combined with a separate activation signal initiated by the switch 38 on the lever knob 4 , sends a signal to the flow limiter 26 for opening. The driver is allowed to move the lever 1 to the R position and, when the R position has been reached, the flow limiter 26 is closed by a signal from the position sensors, 48 and 49 , as a result of which the maneuvering lever is locked against continued movement. In the case of a maneuvering force in the opposite direction, which is detected by the pressure sensors, 31 and 32 , the flow limiter 26 opens first partially and then completely, which provides a threshold effect, i.e. a resistance that has to be overcome. When the N position has been reached, which is detected by the position sensors, a signal is emitted from them to the flow limiter 26 , which is again throttled and creates a certain resistance to continued movement, which in the case of a maneuvering force for movement to the D position (drive position) is reduced by opening of the flow limiter 26 , until the D position has been reached. The position is detected by the position sensors, 48 and 49 , which by means of the control unit 28 close the flow limiter 26 , whereupon the lever 1 is locked against continued shift movement in the same direction.
In the D position, the flow limiter 27 is instead opened at first partially in the case of a maneuvering force in the select direction, by detection of the hydraulic pressure by means of the pressure sensors, 33 and 34 , which by means of the control unit 28 emit a signal to the flow limiter, and then completely in order to allow the select movement in the direction of the arrow 3 for switching to the alternative gear change mode. When the M position has been reached, the flow limiter 27 is closed, whereupon the lever is locked against continued select movement in the same direction. In the M position, the flow limiter 26 is kept continuously closed, while at the same time the flow limiter 47 is opened by means of a signal from the control unit 28 , which is controlled by the position sensors, 48 and 49 , and the pressure sensors, 31 and 32 . The flow is thus opened to the piston cylinders, 41 and 42 , arranged in parallel but the opposite way round.
With a maneuvering force in the shift direction, in this case in the direction from the M position to the − or + position, the hydraulic flow is forced into one or other of the piston cylinders, 41 and 42 , counter to the action of associated springs 45 which have been described above. In this movement too, the lever movement is limited by the position sensors.
The present invention is not limited to the illustrative embodiment described above and shown in the drawing, but instead can be varied within the scope of the attached claims. For example, the system described above can be realized by means of electrical setting devices, for example servo-controlled ball and nut bolts with position sensors which are combined with force sensors, for example strain gauges, which are applied at a suitable location, for example the maneuvering lever, in order to detect the applied maneuvering force. The force sensors should be of the analog type for analog control of the setting devices for a proportioned maneuvering movement. The term analog is in this context also meant to include the technique of simulating an analog technique using a digital technique in small steps.
Although the invention herein has been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present invention. It is therefore to be understood that numerous modifications may be made to the illustrative embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended claims. | Apparatus is disclosed for controlling the operational states of a motor vehicle comprising a maneuvering console including a maneuvering lever, a pivot hinge for the maneuvering lever so that the maneuvering lever can be actuated into a number of positions corresponding to the operational states of the motor vehicle, the pivot hinge being mounted to permit pivoting of the maneuvering lever with respect to the maneuvering console about an unlimited number of spatial pivot axes, a plurality of hydraulic pistons and cylinders mechanically coupled to the maneuvering lever for selectively limiting the pivoting movement of the maneuvering lever, a plurality of sensors for detecting a maneuvering force applied to the maneuvering lever and the position of the maneuvering lever so that the pivoting movement of the maneuvering lever can be selectively limited by the plurality of hydraulic pistons and cylinders based upon those detections, and a controller for controlling the plurality of hydraulic pistons and cylinders thereby permitting selective movement of the maneuvering lever based on control conditions set by the controller. | 8 |
BACKGROUND OF THE INVENTION
The present invention relates to a motor control apparatus for controlling the speed of a motor and, particularly, for setting the speed of the motor.
FIG. 6 is a circuit diagram of a conventional motor control apparatus disclosed in, for example, Japanese Patent Laid-Open No. 87689/1985, and FIG. 7 is a diagram showing a conventional circuit for setting the speed of a sewing machine disclosed in, for example, Japanese Patent Laid-Open No. 136093/ 1984.
In FIGS. 6 and 7, reference numeral 21 denotes a commercial power source, 22 denodes a converter for converting the commercial power source into DC electric power, and 23 denotes an inverter which inverts the DC electric power converted through the converter back to AC electric power of a desired frequency. Reference numeral 24 denotes an electric motor, 25 denotes an encoder for detecting the speed or position of the motor, and 26 denotes a waveform shaping unit for shaping the waveform of pulse signals from the encoder 25.
Reference numeral 27 denotes a speed detector circuit which detects the speed of the motor upon receiving signals from the waveform shaping unit 26, reference numeral 28 denotes a speed feedback signal, and 29 denotes a speed instruction signal that is set by and produced from a speed setting circuit of FIG. 7.
Reference numeral 30 denotes a motor control apparatus, 31 denotes a variable resistor for setting a high speed shown in FIG. 7, and reference numeral 32 denotes a variable resistor for setting a low speed shown in FIG. 7.
The conventional motor control apparatus is constituted as described above. The operation will now be described in conjunction with FIGS. 6 and 7.
Referring to FIG. 6, when the power source 21 is connected to the main circuit unit of the motor control apparatus 30, the electric power causes the motor 24 to rotate passing through the converter 22 and inverter 23 in the main circuit unit. The encoder 25 coupled to the motor 24 sends to the waveform shaping unit 26 the pulse signals of a number proportional to the rotational angle of the motor. The waveform shaping unit 26 which has received the pulse signals determines the forward rotation or the reverse rotation, shapes the waveform, and sends signals to the speed detector circuit 27. Upon receipt of the signals, the speed detector circuit 27 produces a speed feedback signal 28 for the motor 24.
The speed instruction signal 29 of FIG. 6 is obtained from the speed setting circuit of FIG. 7. By setting the variable resistor 31 or 32 of FIG. 7, the speed instruction signals 29 of a frequency corresponding to the speed are sent to the motor control apparatus 30. Upon receipt of speed instruction signals 29, the motor control apparatus 30 compares the speed instruction signals 29 with the speed feedback signals 28, and so controls the motor 24 that its number of revolutions becomes in agreement with the speed instruction signals 29.
FIG. 8 is a diagram which schematically illustrates a conventional motor control apparatus equipped with an A/D converter disclosed in, for example, Japanese Patent Laid-Open No. 97118/1982, Japanese Patent Laid-Open No. 206284/1982 and Japanese Patent Laid-Open No. 208881/1982, and FIG. 9 is a diagram of characteristics representing the speed of a motor corresponding to the voltage obtained through a variable resistor.
In FIG. 8, reference numeral 41 denotes a commercial power source, 42 denotes a motor, and 43 denotes an encoder for detecting the speed or position of the motor.
Reference numeral 44 denotes a speed feedback signal, 45 denotes a speed instruction signal, and 46 denotes a variable resistor for setting a high speed.
Reference numeral 47 denotes a variable resistor for setting a low speed, 48 denotes a motor control apparatus, and 49 denotes a first A/D converter which converts an analog quantity from the variable resistor 46 into a digital quantity.
Reference numeral 50 denotes a second A/D converter which converts an analog quantity from the variable resistor 47 into a digital quantity, and 51 denotes a switch.
The conventional motor control apparatus is constituted as described above. When the power source 41 is connected, the electric power causes the motor 42 to rotate passing through the main circuit unit in the motor control apparatus 48.
To set the speed of the motor 42, the speed instruction voltage obtained by the setting of the variable resistor 46 or 47 is applied to the first A/D converter 49 or the second A/D converter 50 in the motor control apparatus 48. The first A/D converter 49 or the second A/D converter 50 receives the speed instruction voltage and converts it into a digital quantity. The speed instruction voltage converted into a digital quantity is selected by a switch 51 and is produced as a speed instruction signal 45. The motor control apparatus 48 compares the speed instruction signal 45 with a speed feedback signal 44 from the encoder 43 that is coupled to the motor 42, and so controls the motor 42 that its number of revolutions comes into agreement with the speed instruction signal 45.
When the speed is to be set using the above-mentioned conventional motor control apparatus, the variable resistor must be manipulated while measuring the number of revolutions of the motor using a tachometer or the like. Therefore, the speed is set requiring extended periods of time and resulting in an increase in the cost.
SUMMARY OF THE INVENTION
The present invention was accomplished to solve the above-mentioned problems and its object is to provide a motor control apparatus which enables the time for setting the variable resistor to be shortened such that the cost can be decreased.
The motor control apparatus according to the present invention comprises a setter for setting a speed instruction voltage for giving a speed instruction signal to the motor, an A/D converter for converting the speed instruction voltage into a digital quantity, first storage means storing a reference voltage of either a first reference voltage region covering a range of, for example, from 0 V to a first reference voltage V1 or a second reference voltage region covering a range of from a second reference voltage V2 which is greater than the first reference voltage V1 to a maximum voltage (the first or the second reference voltage region is hereinafter simply referred to as "reference voltage region"), and second storage means storing a speed setpoint value corresponding to the reference voltage region.
The apparatus is further equipped with a central processing unit which compares the speed instruction voltage input via the A/D converter with said references voltage, which determines whether the speed instruction voltage lies in the reference voltage region of the first storage means, and which, when the speed instruction voltage lies in the reference voltage region of the first storage means, reads the corresponding speed setpoint value from the second storage means and produces it as a speed instruction signal.
In the present invention, the central processing unit that has received the speed instruction voltage converted into a digital quantity reads a reference voltage stored in the first storage means and determines whether it lies in the reference voltage region. When the speed instruction voltage lies in the reference voltage region, the central processing unit reads from the second storage means a speed setpoint value that corresponds to the reference voltage region, and produces it as a speed instruction signal to control the speed of the motor.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram illustrating the constitution of a control apparatus according to an embodiment of the present invention;
FIG. 2 is a flow chart which illustrates the operation of the control apparatus;
FIGS. 3 and 4 are diagrams of characteristics showing relationships between the reference voltage region and the speed setpoint value that represents a number of revolutions of the motor;
FIG. 5 is a flow chart illustrating means for switching the speed setpoint values;
FIG. 6 is a circuit diagram of a conventional synchronous motor control apparatus;
FIG. 7 is a circuit diagram showing a conventional speed setting circuit for a sawing machine;
FIG. 8 is a diagram which schematically illustrates a conventional motor control apparatus equipped with an A/D converter; and
FIG. 9 is a diagram of conventional characteristics representing the speed of the motor corresponding to a voltage obtained through a variable resistor.
In the drawings, the same reference numerals represent the same or corresponding portions.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 is a block diagram showing the constitution of a control apparatus for controlling the speeds of, for example, a sawing machine set at the time of shipment according to an embodiment of the present invention, FIG. 2 is a flow chart which illustrates the operation of the above-mentioned control apparatus, and FIG. 3(a) is a diagram of characteristics showing a relationship between the speed setpoint value W and the reference voltage region that is set for a speed instruction voltage V according to an embodiment of the present invention.
In FIG. 1, reference numeral 1 denotes setters for setting the speed, and 2 denotes A/D converters for converting analog quantities into digital quantities. In this embodiment, the setters 1 have five speeds, i.e., "high speed", "back tack speed", "low speed", "trim speed" and "positioning speed".
Reference numeral 3 denotes a central processing unit, 4 denotes first storage means which stores a reference voltage of a reference voltage region corresponding to a speed instruction voltage, and 5 denotes second storage means which stores a speed setpoint value corresponding to the reference voltage region.
The portion surrounded by a broken line is a speed instruction system for obtaining any speed by treading the pedal, and wherein reference numeral 61 denotes a pedal and 62 denotes a voltage that varies depending upon the treading amount of the pedal.
Operation of the thus constituted control apparatus will now be described in conjunction with a flow chart of FIG. 2.
The "high speed" can be divided into two of, for example, 2000 spm and 4000 spm depending on the model of the sewing machine. Described below is the case of setting the "high speed" of 2000 spm.
When the "high speed" setter 1 is moved to the extreme left side, the speed instruction voltage V becomes 0 V. The speed instruction voltage V is sent to the A/D converter 2 and is then read by the central processing unit 3 (S1) which also reads from the first memory means (4) a first reference voltage V1 having a maximum value (e.g., 5 V) in the first reference voltage region, and compares the speed instruction voltage V with the first reference voltage V1 (S2). Here, since the speed instruction voltage V is 0 V, a speed setpoint value (W=2000 spm) corresponding thereto is read from the second storage means (5) and is sent as a speed instruction signal W1 to a motor speed control apparatus 30 (S4). The "high speed" is thus set.
Described below is the case where the "high speed" of 4000 spm is to be set. As the "high speed" setter 1 is moved to the extreme right side, the speed instruction voltage V becomes, for example, 16 V. The speed instruction voltage V is sent to the A/D converter 2 and is read by the central processing unit 3 (S1) which also reads from the first memory means 4 the first reference voltage V1 having a maximum value (5 V) of the first reference voltage region, and compares the speed instruction voltage V with the first reference voltage V1 (S2). Here, since the speed instruction voltage V is 16 V, the program proceeds to a step (S3) where a second reference voltage V2 having a minimum value (e.g., 12 V) of the second reference voltage region is read from the first storage means (4) and is compared with the speed instruction voltage V. Here, the speed instruction voltage V is 16 V, and a speed setpoint value (W=4000 spm) corresponding thereto is read from the second storage means 5 and is sent as a speed instruction signal W2 to the motor speed control apparatus 30 (S6). The "high speed" is thus set.
The two sewing machines having the "high speed" of 2000 spm or 4000 spm are further set in regard to their other speeds (back tack speed, low speed, trim speed and positioning speed) in the same manner as the one described above, and are shipped.
When the speed instruction voltage V is greater than the first reference voltage V1 but is smaller than the second reference voltage V2, the speed setpoint value W is obtained by multiplying the speed instruction voltage V by a predetermined value K, enabling the speed to be set continuously.
When the sewing machine is of the model having two "high speeds" of 2000 spm and 4000 spm, the speed instruction signal of 2000 spm is obtained when the "high speed" setter 1 is moved to the extreme left side and the speed instruction signal of 4000 spm is obtained when it is moved to the extreme right side according to the present invention.
Though the above-mentioned embodiment has employed five setters 1, it is of course allowable to use any number of the setters 1.
Further, though the description has dealt with the case of the first reference voltage region and the second reference voltage region set to correspond to the speed instruction voltages, it is further allowable to set only one reference voltage region as shown in FIG. 3(b) to meet the speed instruction voltage.
When the setting range is greater than the first reference voltage V1 but is smaller than the second reference voltage V2, the speed setpoint value W was described to vary in proportion with the speed instruction voltage. However, the speed setpoint value W needs not necessary vary in proportion therewith but may vary according to, for example, a primary function or a secondary function, or may be set to a predetermined value between W1 and W2.
In the above-mentioned embodiment, a variable resistor was used as a setter which, however, may be replaced by any other counterpart provided it is capable of continuously setting the signals. In addition to being set continuously, the control operation is effected while changing the signals into digital signals through the A/D converter. Therefore, the speed is set maintaining high resolution and cheaply yet contributing to improving reliability.
When the motor control apparatus and the speed setting apparatus are used for the sewing machine, many setters are used in a switched manner.
The switching means is explained in a flow chart of FIG. 4.
First, it is determined whether the trim operation is being carried out or not (S11). When the trim operation is being carried out, the speed therefor is set (S16). When it is not, it is determined whether the positioning operation is being carried out or not (S12).
When it is, the positioning speed is set. When it is not, it is then determined whether the low-speed operation is being carried out or not (S21).
Thus, determination is carried out successively to determine whether the back tack operation is being carried out or not (S14) or whether the high-speed operation is being carried out or not (S15).
The setpoint values of the speeds (S16 to S21) shown in FIG. 4 vary depending upon the model of the sewing machine. When the table and the motor are to be used in combination but the sewing machine only is to be changed accompanying the change in the material that is to be sewn, it becomes necessary to change the number of revolutions of the motor.
In such a case, the setter may be so set that the speed instruction voltage lies in the reference voltage region.
The setpoint speeds (S16 to S21) of FIG. 4 can be easily adjusted using means of FIG. 2.
FIG. 5 shows relationships between the models of the sewing machines and the setpoint numbers of revolutions.
If the setpoint numbers of revolutions are all stored in the control apparatus and in the speed setting apparatus, the setters need be adjusted only roughly such that the speed instruction voltage lies in the reference voltage region in order to obtain a predetermined speed instruction signal.
Therefore, the control apparatus of one type only is required and there is no need of replacing the parts or setting the speeds consuming time.
The setting of an intermediate speed between, for example, the speeds V1 and V2 is changed continuously when a fine adjustment is required such as when the seams of back tack operation do not match or when the material to be sewn changes from a thin material to a thick material.
Though in the foregoing was described the case where the speed was set based on the voltage, it is also allowable to set the voltage based on the current, pulses or encoded pulse sequences.
According to the present invention as described above, the setters are so set that the speed instruction setpoint signals lie within a predetermined reference setpoint signal region in order to obtain predetermined speed instruction signals. Therefore, the setting time is reduced and the cost decreases. | A motor control apparatus for a sewing machine includes an adjustable speed setter for generating a speed set signal. A first memory stores a plurality of reference values each defining a reference region into which the speed set signal can fall. A second memory stores speed setpoint values corresponding to the reference regions. A central processing unit selects one of the reference regions by comparing the speed set signal with the reference values and selects the corresponding speed setpoint value from the second memory. A motor is controlled to run at the selected speed setpoint value. | 3 |
BACKGROUND
[0001] The presently disclosed embodiments relate generally to a process for producing emulsion aggregation (EA) toners suitable for electrostatographic apparatuses.
[0002] Numerous processes are within the purview of those skilled in the art for the preparation of EA toners. These toners may be formed by aggregating a colorant with a latex polymer formed by emulsion polymerization. For example, U.S. Pat. No. 5,853,943, the disclosure of which is hereby incorporated by reference in its entirety, is directed to a semi-continuous emulsion polymerization process for preparing a latex by first forming a seed polymer. Other examples of emulsion/aggregation/coalescing processes for the preparation of toners are illustrated in U.S. Pat. Nos. 5,403,693, 5,418,108, 5,364,729, and 5,346,797, the disclosures of each of which are hereby incorporated by reference in their entirety. Other processes are disclosed in U.S. Pat. Nos. 5,527,658, 5,585,215, 5,650,255, 5,650,256 and 5,501,935, the disclosures of each of which are hereby incorporated by reference in their entirety.
[0003] EA toner processes include coagulating a combination of emulsions, i.e., emulsions each including, independent of one another or meaning that they can be the same or different, a latex, wax, pigment, and the like, with a flocculent such as polyaluminum chloride and/or aluminum sulfate, to generate a slurry of primary aggregates which then undergoes a controlled aggregation process. The solid content of this primary slurry dictates the overall throughput of the EA toner process. While an even higher solids content may be desirable, it may be difficult to achieve due to high viscosity of the emulsions and poor mixing, which may lead to the formation of unacceptable primary aggregates (high coarse particle content).
[0004] Current EA toner processes require the addition of flocculent while homogenizing with an IKA homogenizer for small scale production or through an in-line cavitron homogenizer for large scale production. Regardless of scale, homogenization is necessary to ensure a well-distributed flocculent addition resulting in small particle sizes, narrow distributions, and <1% coarse (>16 micron). This then translates to a final toner product complying with <1% coarse (>16 micron) specification. Typically, at the manufacturing scale, the homogenization step requires a minimum of 60 to 90 minutes which results in an overall 8 hours to produce EA toner. Other drawbacks with the current process include flocculent addition errors when dealing with pumping in the flocculent via a homogenizer. Often, the rate of pumping in flocculent is too rapid, or there are leakages. Also the current rotor-stator homogenizer generates about 10-15° C. heat. Thus, it is desirable to reduce the homogenization time (either by not producing the large agglomerates or finding a more effective flocculent distribution method) in order to reduce the overall toner cycle time and the amount of energy used. It is also desirable to reduce production costs for such toners and seek more environmentally friendly processes by reducing leakage of flocculent.
[0005] Improved methods for producing toners, which reduce the number of stages and materials, remain desirable. Acoustic mixing is a new approach to mixing and dispersion of materials ranging from nanoparticle suspensions to viscous gels. It is distinct from conventional impeller agitation found in a planetary mixer or speed mixer as well as ultrasonic mixing. Low frequency, high-intensity acoustic energy is used to create a uniform shear field throughout the entire mixing vessel. The result is rapid fluidization (like a fluidized bed) and dispersion of material. This invention proposes a new and effective flocculent distribution method and process for breaking toner particles with acoustic mixer using low-frequency, high intensity acoustic energy. By using an acoustic mixer, the toner slurry and flocculent can be mixed together and a good distribution of flocculent can be achieved in five (5) minutes, drastically reducing toner cycle time by about 17.8%. In addition, acoustic mixers come in a variety of sizes from a bench top model (roughly 500 milliliters) to manufacturing scale (30 gallons), which enables implantation of this process for both small and large scale purposes.
[0006] Another advantage of such process is that flocculent is now added directly to the slurry before acoustic mixing which reduces the need to pump in flocculent via a homogenizer. As such, there are no leaks as there is no need for material to flow through equipment. Further, the acoustic mixer does not generate any heat and thus, this process can be utilized for heat-sensitive materials.
SUMMARY
[0007] In embodiments, there is provided a method for making a toner particles comprising: a) mixing a composition comprising an amorphous resin emulsion, an optional crystalline resin emulsion, an optional wax emulsion, at least one colorant emulsion to form a composite emulsion; b) adding an aggregating agent to the composite emulsion to form preaggregated particles by subjecting the mixture to acoustic mixing with a g force of from about 50 g to about 100 g; c) aggregating the particles; and optionally, d) forming a shell on the particles to form an emulsion aggregated toner.
[0008] Another embodiment provides a method for making a toner particles comprising: a) mixing a composition comprising an amorphous resin emulsion, an optional crystalline resin emulsion, an optional wax emulsion, at least one colorant emulsion to form a composite emulsion; b) adding an aggregating agent to the composite emulsion to form preaggregated particles by subjecting the mixture to acoustic mixing with a g force of from about 90 g to about 100 g; c) aggregating the particles; and optionally, d) forming a shell on the particles to form an emulsion aggregated toner, wherein no heat is generated during the method for making toner particles.
[0009] In yet another embodiment, there is a method for making a toner particles comprising: a) mixing a composition comprising a linear amorphous resin emulsion, an optional crystalline polyester resin emulsion, an optional wax emulsion, at least one colorant emulsion to form an emulsion; b) adding an aggregating agent to the composite emulsion to form preaggregated particles by subjecting the mixture to acoustic mixing with a g of about 90 g; c) aggregating the particles; and optionally, d) forming a shell on the particles to form an emulsion aggregated toner.
[0010] In yet a further embodiment, there is provided a method for making a toner particles that reduces the overall toner cycle time by up to 20%.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] For a better understanding of the present embodiments, reference may be made to the accompanying figures.
[0012] FIG. 1 is a graph showing particle size (number and volume) distribution of a toner produced in accordance with the present disclosure;
[0013] FIG. 2 is a graph showing particle size (number and volume) distribution of a toner produced in accordance with the present disclosure;
[0014] FIG. 3 is a graph showing particle size (number and volume) distribution of a toner produced in accordance with the present disclosure;
[0015] FIG. 4 is a graph showing particle size (number and volume) distribution of a toner produced in accordance with the present disclosure;
[0016] FIG. 5 is a graph showing particle size (number and volume) distribution of a comparative toner produced in accordance with previous processes; and
[0017] FIG. 6 is a graph showing particle size (number and volume) distribution of a comparative toner produced in accordance with previous processes.
DETAILED DESCRIPTION
[0018] In the following description, reference is made to the accompanying drawings, which form a part hereof and which illustrate several embodiments. It is understood that other embodiments may be utilized and structural and operational changes may be made without departure from the scope of the present disclosure. The same reference numerals are used to identify the same structure in different figures unless specified otherwise. The structures in the figures are not drawn according to their relative proportions and the drawings should not be interpreted as limiting the disclosure in size, relative size, or location.
[0019] Resins
[0020] Any toner resin may be utilized in the processes of the present disclosure. Such resins, in turn, may be made of any suitable monomer or monomers via any suitable polymerization method. In embodiments, the resin may be prepared by a method other than emulsion polymerization. In further embodiments, the resin may be prepared by condensation polymerization.
[0021] In embodiments, the resin may be a polyester, polyimide, polyolefin, polyamide, polycarbonate, epoxy resin, and/or copolymers thereof. In embodiments, the resin may be an amorphous resin, a crystalline resin, and/or a mixture of crystalline and amorphous resins. The crystalline resin may be present in the mixture of crystalline and amorphous resins, for example, in an amount of from 0 to about 50 percent by weight of the total toner resin, in embodiments from 5 to about 35 percent by weight of the toner resin. The amorphous resin may be present in the mixture, for example, in an amount of from about 50 to about 100 percent by weight of the total toner resin, in embodiments from 95 to about 65 percent by weight of the toner resin.
[0022] In embodiments, the amorphous resin may be selected from the group consisting of polyester, a polyamide, a polyimide, a polystyrene-acrylate, a polystyrene-methacrylate, a polystyrene-butadiene, or a polyester-imide, and mixtures thereof. In embodiments, the crystalline resin may be selected from the group consisting of polyester, a polyamide, a polyimide, a polyethylene, a polypropylene, a polybutylene, a polyisobutyrate, an ethylene-propylene copolymer, or an ethylene-vinyl acetate copolymer, and mixtures thereof. In further embodiments, the resin may be a polyester crystalline and/or a polyester amorphous resin. In embodiments, the polymer utilized to form the resin may be a polyester resin, including the resins described in U.S. Pat. Nos. 6,593,049 and 6,756,176. Suitable resins may also include a mixture of an amorphous polyester resin and a crystalline polyester resin as described in U.S. Pat. No. 6,830,860.
[0023] In embodiments, the resin may be a polyester resin formed by reacting a diol with a diacid in the presence of an optional catalyst. For forming a crystalline polyester, suitable organic diols include aliphatic diols with from about 2 to about 36 carbon atoms, such as 1,2-ethanediol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,12-dodecanediol, ethylene glycol, combinations thereof, and the like. The aliphatic diol may be, for example, selected in an amount of from about 40 to about 60 mole percent, in embodiments from about 42 to about 55 mole percent, in embodiments from about 45 to about 53 mole percent of the resin.
[0024] Examples of organic diacids or diesters selected for the preparation of the crystalline resins include oxalic acid, succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, fumaric acid, maleic acid, dodecanedioic acid, sebacic acid, phthalic acid, isophthalic acid, terephthalic acid, naphthalene-2,6-dicarboxylic acid, naphthalene-2,7-dicarboxylic acid, cyclohexane dicarboxylic acid, malonic acid and mesaconic acid, a diester or anhydride thereof, and combinations thereof. The organic diacid may be selected in an amount of, for example, in embodiments from about 40 to about 60 mole percent, in embodiments from about 42 to about 55 mole percent, in embodiments from about 45 to about 53 mole percent.
[0025] Examples of crystalline resins include polyesters, polyamides, polyimides, polyolefins, polyethylene, polybutylene, polyisobutyrate, ethylene-propylene copolymers, ethylene-vinyl acetate copolymers, polypropylene, mixtures thereof, and the like. Specific crystalline resins may be polyester based, such as poly(ethylene-adipate), poly(propylene-adipate), poly(butylene-adipate), poly(pentylene-adipate), poly(hexylene-adipate), poly(octylene-adipate), poly(ethylene-succinate), poly(propylene-succinate), poly(butylene-succinate), poly(pentylene-succinate), poly(hexylene-succinate), poly(octylene-succinate), poly(ethylene-sebacate), poly(propylene-sebacate), poly(butylene-sebacate), poly(pentylene-sebacate), poly(hexylene-sebacate), poly(octylene-sebacate), alkali copoly(5-sulfoisophthaloyl)-copoly(ethylene-adipate), poly(decylene-sebacate), poly(decylene-decanoate), poly-(ethylene-decanoate), poly-(ethylene-dodecanoate), poly(nonylene-sebacate), poly (nonylene-decanoate), copoly(ethylene-fumarate)-copoly(ethylene-sebacate), copoly(ethylene-fumarate)-copoly(ethylene-decanoate), and copoly(ethylene-fumarate)-copoly(ethylene-dodecanoate). The crystalline resin may be present, for example, in an amount of from about 5 to about 50 percent by weight of the toner components, in embodiments from about 10 to about 35 percent by weight of the toner components.
[0026] The crystalline resin can possess various melting points of, for example, from about 30° C. to about 120° C., in embodiments from about 50° C. to about 90° C. The crystalline resin may have a number average molecular weight (Mn), as measured by gel permeation chromatography (GPC) of, for example, from about 1,000 to about 50,000, in embodiments from about 2,000 to about 25,000, and a weight average molecular weight (Mw) of, for example, from about 2,000 to about 100,000, in embodiments from about 3,000 to about 80,000, as determined by Gel Permeation Chromatography using polystyrene standards. The molecular weight distribution (Mw/Mn) of the crystalline resin may be, for example, from about 2 to about 6, in embodiments from about 3 to about 4.
[0027] Examples of diacid or diesters selected for the preparation of amorphous polyesters include dicarboxylic acids or diesters such as terephthalic acid, phthalic acid, isophthalic acid, fumaric acid, maleic acid, succinic acid, itaconic acid, succinic acid, succinic anhydride, dodecylsuccinic acid, dodecylsuccinic anhydride, glutaric acid, glutaric anhydride, adipic acid, pimelic acid, suberic acid, azelaic acid, dodecanediacid, dimethyl terephthalate, diethyl terephthalate, dimethylisophthalate, diethylisophthalate, dimethylphthalate, phthalic anhydride, diethylphthalate, dimethylsuccinate, dimethylfumarate, dimethylmaleate, dimethylglutarate, dimethyladipate, dimethyl dodecylsuccinate, and combinations thereof. The organic diacid or diester may be present, for example, in an amount from about 40 to about 60 mole percent of the resin, in embodiments from about 42 to about 55 mole percent of the resin, in embodiments from about 45 to about 53 mole percent of the resin.
[0028] Examples of diols utilized in generating the amorphous polyester include 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, pentanediol, hexanediol, 2,2-dimethylpropanediol, 2,2,3-trimethylhexanediol, heptanediol, dodecanediol, bis(hydroxyethyl)-bisphenol A, bis(2-hydroxypropyl)-bisphenol A, 1,4-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, xylenedimethanol, cyclohexanediol, diethylene glycol, bis(2-hydroxyethyl)oxide, dipropylene glycol, dibutylene, and combinations thereof. The amount of organic diol selected can vary, and may be present, for example, in an amount from about 40 to about 60 mole percent of the resin, in embodiments from about 42 to about 55 mole percent of the resin, in embodiments from about 45 to about 53 mole percent of the resin.
[0029] In embodiments, polycondensation catalysts may be used in forming the polyesters. Polycondensation catalysts which may be utilized for either the crystalline or amorphous polyesters include tetraalkyl titanates, dialkyltin oxides such as dibutyltin oxide, tetraalkyltins such as dibutyltin dilaurate, and dialkyltin oxide hydroxides such as butyltin oxide hydroxide, aluminum alkoxides, alkyl zinc, dialkyl zinc, zinc oxide, stannous oxide, or combinations thereof. Such catalysts may be utilized in amounts of, for example, from about 0.01 mole percent to about 5 mole percent based on the starting diacid or diester used to generate the polyester resin.
[0030] In embodiments, suitable amorphous resins include polyesters, polyamides, polyimides, polyolefins, polyethylene, polybutylene, polyisobutyrate, ethylene-propylene copolymers, ethylene-vinyl acetate copolymers, polypropylene, combinations thereof, and the like. Examples of amorphous resins which may be utilized include alkali sulfonated-polyester resins, branched alkali sulfonated-polyester resins, alkali sulfonated-polyimide resins, and branched alkali sulfonated-polyimide resins. Alkali sulfonated polyester resins may be useful in embodiments, such as the metal or alkali salts of copoly(ethylene-terephthalate)-copoly(ethylene-5-sulfo-isophthalate), copoly(propylene-terephthalate)-copoly(propylene-5-sulfo-isophthalate), copoly(diethylene-terephthalate)-copoly(diethylene-5-sulfoisophthalate), copoly(propylene-diethylene-terephthalate)-copoly(propylene-diethylene-5-sulfoisophthalate), copoly(propylene-butylene-terephthalate)-copoly(propylene-butylene-5-sulfo-isophthalate), and copoly(propoxylated bisphenol-A-fumarate)-copoly(propoxylated bisphenol A-5-sulfo-isophthalate).
[0031] In embodiments, an unsaturated, amorphous polyester resin may be utilized as a latex resin. Examples of such resins include those disclosed in U.S. Pat. No. 6,063,827. Exemplary unsaturated amorphous polyester resins include, but are not limited to, poly(propoxylated bisphenol co-fumarate), poly(ethoxylated bisphenol co-fumarate), poly(butyloxylated bisphenol co-fumarate), poly(co-propoxylated bisphenol co-ethoxylated bisphenol co-fumarate), poly(1,2-propylene fumarate), poly(propoxylated bisphenol co-maleate), poly(ethoxylated bisphenol co-maleate), poly(butyloxylated bisphenol co-maleate), poly(co-propoxylated bisphenol co-ethoxylated bisphenol co-maleate), poly(1,2-propylene maleate), poly(propoxylated bisphenol co-itaconate), poly(ethoxylated bisphenol co-itaconate), poly(butyloxylated bisphenol co-itaconate), poly(co-propoxylated bisphenol co-ethoxylated bisphenol co-itaconate), poly(1,2-propylene itaconate), and combinations thereof.
[0032] The amorphous resin can possess various glass transition temperatures (Tg) of, for example, from about 40° C. to about 100° C., in embodiments from about 50° C. to about 70° C. The crystalline resin may have a number average molecular weight (M n ), for example, from about 1,000 to about 50,000, in embodiments from about 2,000 to about 25,000, and a weight average molecular weight (M w ) of, for example, from about 2,000 to about 100,000, in embodiments from about 3,000 to about 80,000, as determined by Gel Permeation Chromatography (GPC) using polystyrene standards. The molecular weight distribution (M w /M n ) of the crystalline resin may be, for example, from about 2 to about 6, in embodiments from about 3 to about 4.
[0033] In embodiments, a suitable amorphous polyester resin may be a poly(propoxylated bisphenol A co-fumarate) resin having the following formula (I):
[0000]
[0000] wherein m may be from about 5 to about 1000, in embodiments from about 10 to about 500, in other embodiments from about 15 to about 200. Examples of such resins and processes for their production include those disclosed in U.S. Pat. No. 6,063,827.
[0034] An example of a linear propoxylated bisphenol A fumarate resin which may be utilized as a toner resin is available under the trade name SPARII from Resana S/A Industrias Quimicas, Sao Paulo Brazil. Other propoxylated bisphenol A fumarate resins that may be utilized and are commercially available include GTUF and FPESL-2 from Kao Corporation, Japan, and EM181635 from Reichhold, Research Triangle Park, N.C. and the like.
[0035] Suitable crystalline resins which may be utilized, optionally in combination with an amorphous resin as descried above, include those disclosed in U.S. Patent Application Publication No. 2006/0222991. In embodiments, a suitable crystalline resin may include a resin formed of ethylene glycol and a mixture of dodecanedioic acid and fumaric acid co-monomers with the following formula:
[0000]
[0000] wherein b is from about 5 to about 2000 and d is from about 5 to about 2000.
[0036] For example, in embodiments, a poly(propoxylated bisphenol A co-fumarate) resin of formula I as described above may be combined with a crystalline resin of formula II to form a resin suitable for forming a toner.
[0037] Examples of other suitable toner resins or polymers which may be utilized include those based upon styrenes, acrylates, methacrylates, butadienes, isoprenes, acrylic acids, methacrylic acids, acrylonitriles, and combinations thereof. Exemplary additional resins or polymers include, but are not limited to, poly(styrene-butadiene), poly(methylstyrene-butadiene), poly(methyl methacrylate-butadiene), poly(ethyl methacrylate-butadiene), poly(propyl methacrylate-butadiene), poly(butyl methacrylate-butadiene), poly(methyl acrylate-butadiene), poly(ethyl acrylate-butadiene), poly(propyl acrylate-butadiene), poly(butyl acrylate-butadiene), poly(styrene-isoprene), poly(methylstyrene-isoprene), poly(methyl methacrylate-isoprene), poly(ethyl methacrylate-isoprene), poly(propyl methacrylate-isoprene), poly(butyl methacrylate-isoprene), poly(methyl acrylate-isoprene), poly(ethyl acrylate-isoprene), poly(propyl acrylate-isoprene), poly(butyl acrylate-isoprene); poly(styrene-propyl acrylate), poly(styrene-butyl acrylate), poly(styrene-butadiene-acrylic acid), poly(styrene-butadiene-methacrylic acid), poly(styrene-butadiene-acrylonitrile-acrylic acid), poly(styrene-butyl acrylate-acrylic acid), poly(styrene-butyl acrylate-methacrylic acid), poly(styrene-butyl acrylate-acrylonitrile), and poly(styrene-butyl acrylate-acrylonitrile-acrylic acid), and combinations thereof. The polymer may be block, random, or alternating copolymers.
[0038] In embodiments, the resins may include polyester resins having a glass transition temperature of from about 30° C. to about 80° C., in embodiments from about 35° C. to about 70° C. In further embodiments, the resins utilized in the toner may have a melt viscosity of from about 10 to about 1,000,000 Pa*S at about 130° C., in embodiments from about 20 to about 100,000 Pa*S.
[0039] One, two, or more toner resins may be used. In embodiments where two or more toner resins are used, the toner resins may be in any suitable ratio (e.g., weight ratio) such as for instance about 10% (first resin)/90% (second resin) to about 90% (first resin)/10% (second resin).
[0040] In embodiments, the resin may be formed by emulsion aggregation methods. Utilizing such methods, the resin may be present in a resin emulsion, which may then be combined with other components and additives to form a toner of the present disclosure.
[0041] The polymer resin may be present in an amount of from about 65 to about 95 percent by weight, in embodiments from about 75 to about 85 percent by weight of the toner particles (that is, toner particles exclusive of external additives) on a solids basis. Where the resin is a combination of a crystalline resin and an amorphous resin, the ratio of crystalline resin to amorphous resin can be in embodiments from about 1:99 to about 30:70, in embodiments from about 5:95 to about 25:75, in some embodiments from about 5:95 to about 15:95.
[0042] Surfactants
[0043] In embodiments, resins, colorants, waxes, and other additives utilized to form toner compositions may be in dispersions including surfactants. Moreover, toner particles may be formed by emulsion aggregation methods where the resin and other components of the toner are placed in one or more surfactants, an emulsion is formed, toner particles are aggregated, coalesced, optionally washed and dried, and recovered.
[0044] One, two, or more surfactants may be utilized. The surfactants may be selected from ionic surfactants and nonionic surfactants. Anionic surfactants and cationic surfactants are encompassed by the term “ionic surfactants.” In embodiments, the surfactant may be utilized so that it is present in an amount of from about 0.01% to about 5% by weight of the toner composition, for example from about 0.75% to about 4% by weight of the toner composition, in embodiments from about 1% to about 3% by weight of the toner composition.
[0045] Examples of nonionic surfactants that can be utilized include, for example, polyacrylic acid, methalose, methyl cellulose, ethyl cellulose, propyl cellulose, hydroxy ethyl cellulose, carboxy methyl cellulose, polyoxyethylene cetyl ether, polyoxyethylene lauryl ether, polyoxyethylene octyl ether, polyoxyethylene octylphenyl ether, polyoxyethylene oleyl ether, polyoxyethylene sorbitan monolaurate, polyoxyethylene stearyl ether, polyoxyethylene nonylphenyl ether, dialkylphenoxy poly(ethyleneoxy) ethanol, available from Rhone-Poulenc as IGEPAL CA-210™ IGEPAL CA-520™, IGEPAL CA-720™, IGEPAL CO-890™, IGEPAL CO-720™, IGEPAL CO290™, IGEPAL CA-210™, ANTAROX890™ and ANTAROX897™. Other examples of suitable nonionic surfactants include a block copolymer of polyethylene oxide and polypropylene oxide, including those commercially available as SYNPERONIC PE/F, in embodiments SYNPERONIC PE/F 108.
[0046] Anionic surfactants which may be utilized include sulfates and sulfonates, sodium dodecylsulfate (SDS), sodium dodecylbenzene sulfonate, sodium dodecylnaphthalene sulfate, dialkyl benzenealkyl sulfates and sulfonates, acids such as abitic acid available from Aldrich, NEOGEN R™, NEOGEN SC™ obtained from Daiichi Kogyo Seiyaku, combinations thereof, and the like. Other suitable anionic surfactants include, in embodiments, DOWFAX™ 2A1, an alkyldiphenyloxide disulfonate from The Dow Chemical Company, and/or TAYCA POWER BN2060 from Tayca Corporation (Japan), which are branched sodium dodecyl benzene sulfonates. Combinations of these surfactants and any of the foregoing anionic surfactants may be utilized in embodiments.
[0047] Examples of the cationic surfactants, which are usually positively charged, include, for example, alkylbenzyl dimethyl ammonium chloride, dialkyl benzenealkyl ammonium chloride, lauryl trimethyl ammonium chloride, alkylbenzyl methyl ammonium chloride, alkyl benzyl dimethyl ammonium bromide, benzalkonium chloride, cetyl pyridinium bromide, C 12 , C 15 , C 17 trimethyl ammonium bromides, halide salts of quaternized polyoxyethylalkylamines, dodecylbenzyl triethyl ammonium chloride, MIRAPOL™ and ALKAQUAT™, available from Alkaril Chemical Company, SANIZOL™ (benzalkonium chloride), available from Kao Chemicals, and the like, and mixtures thereof.
[0048] Colorants
[0049] As the colorant to be added, various known suitable colorants, such as dyes, pigments, mixtures of dyes, mixtures of pigments, mixtures of dyes and pigments, and the like, may be included in the toner. The colorant may be included in the toner in an amount of, for example, about 0.1 to about 35 percent by weight of the toner, or from about 1 to about 15 weight percent of the toner, or from about 3 to about 10 percent by weight of the toner.
[0050] As examples of suitable colorants, mention may be made of carbon black like REGAL 330®; magnetites, such as Mobay magnetites MO8029™, MO8060™; Columbian magnetites; MAPICO BLACKS™ and surface treated magnetites; Pfizer magnetites CB4799™, CB5300™, CB5600™, MCX6369™; Bayer magnetites, BAYFERROX 8600™, 8610™; Northern Pigments magnetites, NP-604™, NP-608™; Magnox magnetites TMB-100™, or TMB-104™; and the like. As colored pigments, there can be selected cyan, magenta, yellow, red, green, brown, blue or mixtures thereof. Generally, cyan, magenta, or yellow pigments or dyes, or mixtures thereof, are used. The pigment or pigments are generally used as water based pigment dispersions.
[0051] Specific examples of pigments include SUNSPERSE 6000, FLEXIVERSE and AQUATONE water based pigment dispersions from SUN Chemicals, HELIOGEN BLUE L6900™, D6840™, D7080™, D7020™, PYLAM OIL BLUE™, PYLAM OIL YELLOW™, PIGMENT BLUE 1™ available from Paul Uhlich & Company, Inc., PIGMENT VIOLET 1™, PIGMENT RED 48™, LEMON CHROME YELLOW DCC 1026™ E.D. TOLUIDINE RED™ and BON RED C™ available from Dominion Color Corporation, Ltd., Toronto, Ontario, NOVAPERM YELLOW FGL™, HOSTAPERM PINK E™ from Hoechst, and CINQUASIA MAGENTA™ available from E.I. DuPont de Nemours & Company, and the like. Generally, colorants that can be selected are black, cyan, magenta, or yellow, and mixtures thereof. Examples of magentas are 2,9-dimethyl-substituted quinacridone and anthraquinone dye identified in the Color Index as CI-60710, CI Dispersed Red 15, diazo dye identified in the Color Index as CI-26050, CI Solvent Red 19, and the like. Illustrative examples of cyans include copper tetra(octadecyl sulfonamido) phthalocyanine, x-copper phthalocyanine pigment listed in the Color Index as CI-74160, CI Pigment Blue, Pigment Blue 15:3, and Anthrathrene Blue, identified in the Color Index as CI-69810, Special Blue X-2137, and the like. Illustrative examples of yellows are diarylide yellow 3,3-dichlorobenzidene acetoacetanilides, a monoazo pigment identified in the Color Index as CI-12700, CI Solvent Yellow 16, a nitrophenyl amine sulfonamide identified in the Color Index as Foron Yellow SE/GLN, CI Dispersed Yellow 33 2,5-dimethoxy-4-sulfonanilide phenylazo-4′-chloro-2,5-dimethoxy acetoacetanilide, and Permanent Yellow FGL. Colored magnetites, such as mixtures of MAPICO BLACK™, and cyan components may also be selected as colorants. Other known colorants can be selected, such as Levanyl Black A-SF (Miles, Bayer) and Sunsperse Carbon Black LHD 9303 (Sun Chemicals), and colored dyes such as Neopen Blue (BASF), Sudan Blue OS (BASF), PV Fast Blue B2GO1 (American Hoechst), Sunsperse Blue BHD 6000 (Sun Chemicals), Irgalite Blue BCA (Ciba-Geigy), Paliogen Blue 6470 (BASF), Sudan III (Matheson, Coleman, Bell), Sudan II (Matheson, Coleman, Bell), Sudan IV (Matheson, Coleman, Bell), Sudan Orange G (Aldrich), Sudan Orange 220 (BASF), Paliogen Orange 3040 (BASF), Ortho Orange OR 2673 (Paul Uhlich), Paliogen Yellow 152, 1560 (BASF), Lithol Fast Yellow 0991K (BASF), Paliotol Yellow 1840 (BASF), Neopen Yellow (BASF), Novoperm Yellow FG 1 (Hoechst), Permanent Yellow YE 0305 (Paul Uhlich), Lumogen Yellow D0790 (BASF), Sunsperse Yellow YHD 6001 (Sun Chemicals), Suco-Gelb L1250 (BASF), Suco-Yellow D1355 (BASF), Hostaperm Pink E (American Hoechst), Fanal Pink D4830 (BASF), Cinquasia Magenta (DuPont), Lithol Scarlet D3700 (BASF), Toluidine Red (Aldrich), Scarlet for Thermoplast NSD PS PA (Ugine Kuhlmann of Canada), E.D. Toluidine Red (Aldrich), Lithol Rubine Toner (Paul Uhlich), Lithol Scarlet 4440 (BASF), Bon Red C (Dominion Color Company), Royal Brilliant Red RD-8192 (Paul Uhlich), Oracet Pink RF (Ciba-Geigy), Paliogen Red 3871K (BASF), Paliogen Red 3340 (BASF), Lithol Fast Scarlet L4300 (BASF), combinations of the foregoing, and the like.
[0052] Wax
[0053] Optionally, a wax may also be combined with the resin and optional colorant in forming toner particles. When included, the wax may be present in an amount of, for example, from about 1 weight percent to about 25 weight percent of the toner particles, in embodiments from about 5 weight percent to about 20 weight percent of the toner particles.
[0054] Waxes that may be selected include waxes having, for example, a weight average molecular weight of from about 500 to about 20,000, in embodiments from about 1,000 to about 10,000. Waxes that may be used include, for example, polyolefins such as polyethylene, polypropylene, and polybutene waxes such as commercially available from Allied Chemical and Petrolite Corporation, for example POLYWAX™ polyethylene waxes from Baker Petrolite, wax emulsions available from Michaelman, Inc. and the Daniels Products Company, EPOLENE N-15™ commercially available from Eastman Chemical Products, Inc., and VISCOL 550-P™, a low weight average molecular weight polypropylene available from Sanyo Kasei K. K.; plant-based waxes, such as carnauba wax, rice wax, candelilla wax, sumacs wax, and jojoba oil; animal-based waxes, such as beeswax; mineral-based waxes and petroleum-based waxes, such as montan wax, ozokerite, ceresin, paraffin wax, microcrystalline wax, and Fischer-Tropsch wax; ester waxes obtained from higher fatty acid and higher alcohol, such as stearyl stearate and behenyl behenate; ester waxes obtained from higher fatty acid and monovalent or multivalent lower alcohol, such as butyl stearate, propyl oleate, glyceride monostearate, glyceride distearate, and pentaerythritol tetra behenate; ester waxes obtained from higher fatty acid and multivalent alcohol multimers, such as diethyleneglycol monostearate, dipropyleneglycol distearate, diglyceryl distearate, and triglyceryl tetrastearate; sorbitan higher fatty acid ester waxes, such as sorbitan monostearate, and cholesterol higher fatty acid ester waxes, such as cholesteryl stearate. Examples of functionalized waxes that may be used include, for example, amines, amides, for example AQUA SUPERSLIP 6550™, SUPERSLIP 6530™ available from Micro Powder Inc., fluorinated waxes, for example POLYFLUO 190™, POLYFLUO 200™, POLYSILK 19™ POLYSILK 14™ available from Micro Powder Inc., mixed fluorinated, amide waxes, for example MICROSPERSION 19™ also available from Micro Powder Inc., imides, esters, quaternary amines, carboxylic acids or acrylic polymer emulsion, for example JONCRYL 74™, 89™, 130™, 837™, and 538™, all available from SC Johnson Wax, and chlorinated polypropylenes and polyethylenes available from Allied Chemical and Petrolite Corporation and SC Johnson wax. Mixtures and combinations of the foregoing waxes may also be used in embodiments. Waxes may be included as, for example, fuser roll release agents.
[0055] Toner Preparation
[0056] The toner particles may be prepared by any method within the purview of one skilled in the art. Although embodiments relating to toner particle production are described below with respect to emulsion-aggregation processes, any suitable method of preparing toner particles may be used, including chemical processes, such as suspension and encapsulation processes disclosed in U.S. Pat. Nos. 5,290,654 and 5,302,486. In embodiments, toner compositions and toner particles may be prepared by aggregation and coalescence processes in which small-size resin particles are aggregated to the appropriate toner particle size and then coalesced to achieve the final toner particle shape and morphology.
[0057] In embodiments, toner compositions may be prepared by emulsion-aggregation processes, such as a process that includes aggregating a mixture of an optional colorant, an optional wax and any other desired or required additives, and emulsions including the resins described above, optionally in surfactants as described above, and then coalescing the aggregate mixture. In embodiments, emulsions of each of the components are prepared and then combined together in a composite emulsion. A mixture may be prepared by adding a colorant and optionally a wax or other materials, which may also be optionally in a dispersion(s) including a surfactant, to the emulsion, which may be a mixture of two or more emulsions containing the resin. The pH of the resulting mixture may be adjusted by an acid such as, for example, acetic acid, nitric acid or the like. In embodiments, the pH of the mixture may be adjusted to from about 4 to about 5.
[0058] Following the preparation of the above mixture, an aggregating agent or flocculent may be added to the mixture. Any suitable aggregating agent may be utilized to form a toner. Suitable aggregating agents include, for example, aqueous solutions of a divalent cation or a multivalent cation material. The aggregating agent may be, for example, polyaluminum halides such as polyaluminum chloride (PAC), or the corresponding bromide, fluoride, or iodide, polyaluminum silicates such as polyaluminum sulfosilicate (PASS), and water soluble metal salts including aluminum chloride, aluminum nitrite, aluminum sulfate, potassium aluminum sulfate, calcium acetate, calcium chloride, calcium nitrite, calcium oxylate, calcium sulfate, magnesium acetate, magnesium nitrate, magnesium sulfate, zinc acetate, zinc nitrate, zinc sulfate, zinc chloride, zinc bromide, magnesium bromide, copper chloride, copper sulfate, and combinations thereof. In embodiments, the aggregating agent may be added to the mixture at a temperature that is below the glass transition temperature (Tg) of the resin.
[0059] The aggregating agent may be added to the mixture utilized to form a toner in an amount of, for example, from about 0.1% to about 8% by weight, in embodiments from about 0.2% to about 5% by weight, in other embodiments from about 0.5% to about 5% by weight, of the resin in the mixture. This provides a sufficient amount of agent for aggregation.
[0060] In embodiments, the aggregating agent is added to the slurry and then mixed in LabRAM ResonantAcoustic Mixers with a g force applied by the acoustic mixer to the mix load of from about 90 g to about 100 g (one g=9.81 m/S 2 ). Resonant acoustic mixing is distinct from conventional impeller agitation found in a planetary mixer or ultrasonic mixing. Low frequency, high-intensity acoustic energy is used to create a uniform shear field throughout the entire mixing vessel. The result is rapid fluidiziation (like a fluidized bed) and dispersion of material. Resonant acoustic mixing differs from ultrasonic mixing in that the frequency of acoustic energy is orders of magnitude lower. As a result, the scale of mixing is larger. Unlike impeller agitation, which mixes by inducing bulk flow, the acoustic mixing occurs on a microscale throughout the mixing volume.
[0061] In acoustic mixing, acoustic energy is delivered to the components to be mixed. An oscillating mechanical driver creates a motion in a mechanical system comprised of engineered plates, eccentric weights and springs. This energy is then acoustically transferred to the material to be mixed. The underlying technology principle is that the system operates at resonance. In this mode, there a nearly complete exchange of energy between the mass elements and the elements in the mechanical system. In a resonant acoustic mixing, the only element that absorbs energy (apart from some negligible friction losses) is the mix load itself. Thus, the resonant acoustic mixing provides a highly efficient way of transferring mechanical energy directly into the mixing materials. In the mixing of developer, the resonant frequency is the container and its contents, for example, the toner particles and the carrier particles.
[0062] In embodiments, the acoustic mixing occurs for a period of time of from about 5 minutes to about 10 minutes or for a period of time of from about 4 minutes to about 5 minutes. The mixing may be performed with various milling media, such as beads. The milling media may comprise a material selected from the group consisting of glass, steel, ceramic and mixtures of. The acoustic mixing, in embodiments, occurs at a temperature of from about 0° C. to about 50° C. or of from about 20° C. to about 30° C. The slurry may be mixed at a resonant frequency of from about 15 Hz to about 2000 Hz, or from about 20 Hz to about 1800 Hz, or from about 20 Hz to about 1700 Hz. The g force applied by the acoustic mixer to the mix load can be from about 50 g to about 100 g. In a specific embodiment, the slurry is mixed at a g force of about 90 g for about 5 minutes. In embodiments, the toner slurry has a solids content of from about 5 to about 30 percent solids by total weight of the toner slurry.
[0063] The particles may be permitted to aggregate until a predetermined desired particle size is obtained. A predetermined desired size refers to the desired particle size to be obtained as determined prior to formation, and the particle size being monitored during the growth process until such particle size is reached. Samples may be taken during the growth process and analyzed, for example with a Coulter Counter, for average particle size. The aggregation thus may proceed by maintaining the elevated temperature, or slowly raising the temperature to, for example, from about 30° C. to about 99° C., and holding the mixture at this temperature for a time from about 0.5 hours to about 10 hours, in embodiments from about hour 1 to about 5 hours, while maintaining stirring, to provide the aggregated particles. Once the predetermined desired particle size is reached, then the growth process is halted. In embodiments, the predetermined desired particle size is within the toner particle size ranges mentioned above.
[0064] In embodiments, the toner particles may have the following characteristics:
[0065] (1) Volume average diameter (also referred to as “volume average particle diameter”) of from about 1.15 microns to about 1.25 microns.
[0066] (2) Number Average Geometric Size Distribution (GSDn) of from about 1 to about 25, and/or Volume Average Geometric Size Distribution (GSDv) of from about 1.10 to about 1.28.
[0067] The characteristics of the toner particles may be determined by any suitable technique and apparatus. Volume average particle diameter D50, GSDv and GSDn may be measured by means of a measuring instrument such as a Beckman Coulter, operated in accordance with the manufacturer's instructions. Once completed a sample, quenched in 4% NaOH and DIW is taken for particle size measurement on the coulter counter.
[0068] While the description above refers to particular embodiments, it will be understood that many modifications may be made without departing from the spirit thereof. The accompanying claims are intended to cover such modifications as would fall within the true scope and spirit of embodiments herein.
[0069] The presently disclosed embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, the scope of embodiments being indicated by the appended claims rather than the foregoing description. All changes that come within the meaning of and range of equivalency of the claims are intended to be embraced therein.
EXAMPLES
[0070] The example set forth herein below is illustrative of different compositions and conditions that can be used in practicing the present embodiments. All proportions are by weight unless otherwise indicated. It will be apparent, however, that the embodiments can be practiced with many types of compositions and can have many different uses in accordance with the disclosure above and as pointed out hereinafter.
[0071] The embodiments will be described in further detail with reference to the following examples and comparative examples. All the “parts” and “%” used herein mean parts by weight and % by weight unless otherwise specified.
Example 1
[0072] An emulsion aggregation toner was prepared as follows. Briefly, about 17.5 grams of a linear amorphous resin A in an emulsion (about 35 weight % resin) and 17.9 grams of a linear amorphous resin B in an emulsion (about 34 weight % resin) were added to a 200 milliliter plastic container (with lid). The linear amorphous resins A and B were of the following formula:
[0000]
[0000] wherein m for linear amorphous resin A is from about 2 to about 10, and m for linear amorphous resin B is from about 2 to about 10; these resins were produced following the procedures described in U.S. Pat. No. 6,063,827. About 4.7 grams of a crystalline polyester resin composed of dodecanedioic acid and 1,9-Nonanediol with the following formula:
[0000]
[0000] wherein b is from about 5 to about 2000 and d is from about 5 to about 2000, in an emulsion (about 10 weight % resin), synthesized following the procedures described in U.S. Patent Application Publication No. 2006/0222991, with about 8.5 grams of a cyan pigment, Pigment Blue 15:3 (about 1 wt %), about 0.59 grams of surfactant (Dowfax), about 7.4 grams of a polyethylene wax (about 1.5 wt %), and about 84 grams of deionized water, were added to the container. The pH of the mixture was adjusted to about 4.2 by adding nitric acid (about 0.3M). About 0.12 grams of Al 2 (SO 4 ) 3 (about 27.8 weight %) was added as a flocculent to the slurry. About 83 grams of 3 millimeter stainless steel beads were added to the resulting slurry. The plastic container is then sealed with a lid and placed into an acoustic mixer (a LABRAM mixer from Resodyn Acoustic Mixers, Inc. (Butte, Mont.)) for 5 minutes and a resonant frequency of about 65 Hz. Once mixed, the particle characteristics were measured using the Coulter counter with the results shown in FIG. 1 (Coulter Trace of Toner Slurry after Resodyn mixer with 0% coarse). In this manner with a homogenizer, the flocculent addition occurs in-line drop wisely while homogenizing.
[0073] The slurry is then transferred to a 200 milliliter glass beaker with one P4 mixing blade on a hotplate. The final toner slurry has a % coarse of 0.39. The particle characteristics were once again measured using the Coulter counter with the results shown in FIG. 2 (Coulter Trace of final EA toner with 0.39% coarse).
[0074] Thereafter, the toner particles are aggregated and may optionally have a shell formed over the particles.
Example 2
[0075] An EA toner was prepared by following the same procedures and material compositions as those described in Example 1 above, but with the exception that no stainless steel beads were used. Once mixed, the particle characteristics for the toner slurry after acoustic mixing and the final toner were measured using the Coulter counter with the results shown in FIG. 3 (Coulter Trace of Toner Slurry after Resodyn mixer with 0.49% coarse) and FIG. 4 (Coulter Trace of final EA Pinot toner with 0.47% coarse.).
Comparative Example 1
[0076] Briefly, in a 2 liter plastic beaker, the two amorphous resins (about 147 grams of linear amorphous resin A in an emulsion (about 35.2 weight % resin) and about 154 grams of linear amorphous resin B in an emulsion (about 33 weight % resin) were added with 45 grams of a crystalline polyester resin emulsion, 4.89 grams of surfactant (Dowfax), 62 grams of wax (IGI), 71 grams of a cyan pigment, Pigment Blue 15:3 (about 15.6 wt %), and about 589 grams of deionized water. The pH of the mixture was adjusted to about 4.2 by adding about 5 gram of nitric acid (about 0.3M). The slurry is then homogenized for a total of 5 minutes at 3000-4000 rpm while adding in the flocculent, about 49.8 grams of Al 2 (SO 4 ) 3 (about 10 weight %). Once completed, a sample, quenched in 4% NaOH and deionized water, is drawn for particle size measurement on the Coulter Counter, with the results shown in FIG. 5 (Coulter trace after flocculent addition using IKA Homogenizer with 0% coarse) and FIG. 6 (Coulter trace after flocculent addition using IKA Homogenizer with 2.83% coarse).
[0077] Toners from this Comparative Example 1 were compared with the toners produced in Examples 1 and 2. Particle size, volume average geometric size distribution (GSD v ), number average geometric size distribution (GSD n ), and % coarseness are set forth below in Table 1.
[0000]
TABLE 1
D 50
%
(microns)
GSD v
GSD n
coarse
Example 1
2.86
1.3552
1.369
0
(K694C with
Stainless Steel
Beads)
Example 2
2.78
1.3265
1.3405
0.49
(K689C without
Stainless Steel
Beads)
Comparative
1.3268
1.3268
1.3564
0
Example 1
(KNPE529C using
IKA Homogenizer)
[0078] As shown in Table 1 above, the EA toner particles prepared by the process of the present disclosure (Examples 1 and 2) had similar properties compared with the toner of Comparative Example 1, with overall reduced toner cycle time of 17.8%. The resulting toner particles also show comparable GSD values, demonstrating that the process utilized to prepare the toner of the present disclosure had minimal impact on the final toner properties.
[0079] The present embodiments provide a method for making toner particles which provides a number of benefits over prior methods, including the ability to mix in flocculent (with or without beads) into an EA toner slurry without the use of a homogenizer, preventing pre-mature toner growth useful for heat sensitive materials (no heat generated by the mixing), a “one-pot” system with very low chance for equipment failure due to leaks or improper pumping, and a reduction of overall toner cycle time by up to 20%.
[0080] It will be appreciated that several of the above-disclosed and other features and functions, or alternatives thereof, may be desirably combined into many other different systems or applications. Also that various presently unforeseen or unanticipated alternatives, modifications, variations or improvements therein may be subsequently made by those skilled in the art which are also intended to be encompassed by the following claims. Unless specifically recited in a claim, steps or components of claims should not be implied or imported from the specification or any other claims as to any particular order, number, position, size, shape, angle, color, or material. | A process for making emulsion aggregation (EA) toners is provided. In embodiments, the process comprises aggregating a mixture comprising a latex resin, and at least one colorant in a reactor to form aggregated toner particles, adding a shell resin to form a shell over the aggregated toner particles, coalescing the aggregated toner particles, and recovering the toner particles. | 6 |
BACKGROUND OF THE INVENTION
The present invention relates to a process and device for removing an object to be cut. More particularly, the invention relates to a process for collecting an asbestos layer by suction and simultaneously cutting the same, and further carrying the asbestos to a carrier container in order to maintain a sanitary and safe operational environment for individuals engaging in removing the asbestos layer. In removing the asbestos layer, dust and waste generated exert a bad influence upon the human body, which causes serious problems.
Previously, in removing the sprayed asbestos, a work field for removing the asbestos was closely covered with a vinyl sheet in order to prevent scattering of asbestos dust. Additional load was applied to the inside thereof. Thereafter, the asbestos was scraped onto a floor by means of a scraper, brush and large aspirator for use, while spraying or sprinkling water or wetting material thereon in order to reduce the fugacity of the asbestos thus cut. Therefore, according to the conventional removing process of the asbestos, asbestos dust hangs over the work field, which caused a considerably poor operational environment. Furthermore, in employing the large aspirator, scraping and suctioning of the asbestos layer were separately carried out, complicating the operation while suspended dust density within the work field increased. As a result, a worker or any other person standing in the vicinity of said worker was thereby adversely affected. Furthermore, since no apertures in the shape of a window are perforated in the wall surface of an attachment connected to the conventional aspirator
through a hose, it is difficult to easily move or shift the face of said attachment due to close suction of a suction inlet onto the wall surface.
SUMMARY OF THE INVENTION
With the above in mind, it is an object of the present invention to provide a process for collecting sprayed asbestos by suction simultaneously with cutting the same, and further carrying the asbestos thus cut to a carrier container in order to maintain the safe and sanitary operation environment of those who are engaging in removing the asbestos.
Another object of the present invention is to provide a device for carrying out said process with an improved attachment of said device.
The aforementioned objects can be attained by a process comprising a sprayed asbestos layer being cut and suctioned simultaneously therewith by means of a scraper and a suction air duct, the asbestos thus suctioned being led into a collector through a closed conduit to collect said asbestos dust within water as a primary collecting process. A secondary collecting process is carried out by means of a wet type cyclone and by showering the air passing through said collector. Then, a tertiary collecting process is carried out to collect the air passing through the secondary process by means of a compound filter. A device is employed comprising an attachment consisting of a scraper integrally formed with a suction air duct provided with a plurality of apertures in the shape of a window perforated therein and a suction inlet. A closed conduit for carrying the asbestos dust thus suctioned is connected to said air duct through a hose, a collector, a wet type cyclone and a scrubber connected to each other within said closed conduit. A compound filter is disposed at a final position of said closed conduit.
As described above, according to the present invention, it becomes possible to suction the asbestos dust generated from cutting the asbestos layer by means of a suction air duct without scattering or dropping said dust. A collector can collect the suctioned asbestos together with the dust thereof and at the same time can dampen the same in order to prevent the asbestos from scattering in a further process. The wet type cyclone and scrubber can collect a fine asbestos dust which is rather difficult to collect by means of a primary collector. In order to enhance the collecting function of said cyclone and scrubber, a shower ring is supplementally provided. A compound filter can finally remove a fine asbestos dust which can not be collected by means of said cyclone and scrubber and then exhausts.
It is further possible to scrape the asbestos layer by means of a scraper integrally formed with the suction air duct while pressing a suction inlet thereof against a ceiling or wall surface. Since apertures in the shape of a window are perforated in said air duct, it is possible to suction air through the apertures, thereby facilitating the face shift of said suction inlet along the ceiling or wall surface and further suction asbestos dust floating outside of the suction duct thereinto.
BRIEF DESCRIPTION OF THE DRAWINGS
In the Figures,
FIG. 1 is a flow chart showing the process according to the present invention;
FIG. 2 is a front view of the device according to the
present invention;
FIG. 3 is a plan view of said device, wherein said device is loaded onto a truck;
FIG. 4 is a perspective view of a first embodiment of an attachment applied to the device according to the present invention;
FIG. 5 is a perspective view of a second embodiment of an attachment applied to the device according to the present invention;
FIG. 6 is a perspective view of a third embodiment of an attachment applied to the device according to the present invention; and
FIG. 7 is a perspective view of a fourth embodiment of an attachment applied to the device according to the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Hereinafter, embodiments according to the present invention will be described in detail with reference to the drawings.
FIG. 4 to FIG. 7 illustrate embodiments according to the present invention in which an attachment (a) is applied to the device of the invention. Said attachment consists of a scraper 1, a suction inlet 17, a suction air duct 2, and apertures 15 in the shape of a window perforated in said air duct which is connected to a hose 9.
In FIGS. 1-7, the scraper 1 is projectingly formed at an upper end of the air duct 2 in the shape of a cutter. An asbestos layer A is scraped by means of the scraper by pressing the suction inlet 17 of said air duct 2 against a ceiling or wall surface. The asbestos thus scraped is collected into a collector 4 through the hose 9. Since the apertures 15 are perforated in the air duct at a prescribed position in the vicinity of the suction inlet 17, surrounding air and floating asbestos can be suctioned into the air duct through said apertures 15. Accordingly, it is possible to avoid shifting difficulty of the air duct due to the close suction onto the ceiling or wall surface of a building.
In FIG. 2, an upper end of the scraper 1 is bent upwardly in the shape of a cutter and the asbestos layer is scraped by means of said scraper by positioning the air duct 17 directly below said scraper while pressing the same against the ceiling, etc.
In FIG. 6, a brush is mounted inside the air inlet 17 and in FIG. 7, a rotary electric brush is mounted inside the air inlet 17, which are other respective embodiments of the scraper 1.
According to the embodiment illustrated in FIG. 7, the asbestos thus scraped scatters in the tangential direction thereof. Therefore, a raised portion 16 is formed so as to completely collect the scattering asbestos.
FIG. 1 is a flow chart according to the present invention. FIG. 2 is a front view of the device according to the present invention and FIG. 3 is a plan view showing one embodiment of said device, wherein said device is loaded on a truck.
Hereinafter the process of the present invention will be described with reference to FIG. 1. As illustrated in FIG. 1, said process comprises a preliminary cleaning process and cutting process at a work field, then a primary collecting process by means of a collector, then a secondary collecting process by means of a cyclone, then a tertiary collecting process by means of a scrubber, and then a final dust removing process by means of a compound filter to exhaust. Through said secondary and tertiary processes, a closed process to a carrier container, then to another carrier container, and then a carrying-in process to a final disposable lot are carried out.
As illustrated in FIG. 2 and FIG. 3, the asbestos layer A sprayed onto the wall surface of a ceiling, etc. is scraped by means of the scraper 1 and suctioned through the suction air duct 2. The asbestos thus scraped together with the dust thereof are collected into the collector 4 through the air duct 2 and hose 9. Said collector 4 stores water 10 therewithin and an end portion of said hose 9 is open within said water 10. Accordingly, the dust of the asbestos is collected within water 10 (Primary collecting process).
The air passing through said collector 4 is let into a wet-type cyclone 6 through a closed conduit 3. Within said cyclone 6, a shower 5 is mounted so as to shower the inside of said cyclone (Secondary collecting process). Next, the air passing through the cyclone 6 is led into a scrubber 7 through the other closed conduit 3. The other shower 5 is also mounted within scrubber 7 so as to shower the inside of said scrubber 7 (Tertiary collecting process).
The air passing through said scrubber 7 is exhausted through another closed conduit 3 and further through a compound filter 8. Said compound filter 8 consists of a high efficiency filter 8a, a filter 8b and a pre-filter 8c. In the Figures, reference numeral 11 denotes a pipe (P) connecting to a carrier container 13. Reference numeral 12 denotes a blower and reference numeral 14 denotes a truck. In the above embodiment, the device according to the present invention is loaded onto a truck 14. Accordingly, it is possible to move the device easily to a work field so as to carry out the aforementioned primary, secondary and tertiary collecting processes, thereby finally obtaining clean air through the compound filter.
Furthermore, it is possible to apply the device and process to local demolition work in connection with partial repairs of a building, scavenging operation of a road, or cleaning of a construction, for the removal of the asbestos as described above.
Thus, according to the present invention, it is possible to collect the scraped asbestos together with the dust thereof simultaneously with cutting an asbestos layer by means of the scraper. It is further possible to collect floating asbestos through the apertures perforated in the suction air duct. Therefore, a collecting process of the asbestos becomes effective and further a face shift of the attachment becomes easy. Still furthermore, according to the present invention, asbestos dust concentration during the operation can be considerably reduced compared with that of the conventional technique, thereby improving the sanitary environment of those who are engaged in removing asbestos sprayed onto the ceiling, etc. At the same time, it is possible to improve operation efficiency and also reduce operation costs thereof. | A process and device for removing a sprayed asbestos layer are provided, in which the asbestos is simultaneously cut and suctioned by a scraper and a suction air duct, and then transported into a carrier container for collection through primary, secondary and tertiary collection steps, in order to maintain a safe and sanitary operational environment for those who are engaged in removing the asbestos layer. | 1 |
This invention is related to measurements made while drilling a well borehole, and more particularly toward methodology for transferring data between the surface of the earth and sensors or other instrumentation disposed below a mud motor in a drill string.
BACKGROUND OF THE INVENTION
Borehole geophysics encompasses a wide range of parametric borehole measurements. Included are measurements of chemical and physical properties of earth formations penetrated by the borehole, as well as properties of the borehole and material therein. Measurements are also made to determine the path of the borehole. These measurements can be made during drilling and used to steer the drilling operation, or after drilling for use in planning additional well locations.
Borehole instruments or “tools” comprise one or more sensors that are used to measure “logs” of parameters of interest as a function of depth within the borehole. These tools and their corresponding sensors typically fall into two categories. The first category is “wireline” tools wherein a “logging” tool is conveyed along a borehole after the borehole has been drilled. Conveyance is provided by a wireline with one end attached to the tool and a second end attached to a winch assembly at the surface of the earth. The second category is logging-while-drilling (LWD) or measurement-while-drilling (MWD) tools, wherein the logging tool is an element of a bottom hole assembly. The bottom hole assembly is conveyed along the borehole by a drill string, and measurements are made with the tool while the borehole is being drilled.
A drill string typically comprises a tubular which is terminated at a lower end by a drill bit, and terminated at an upper end at the surface of the earth by a “drilling rig” which comprises draw works and other apparatus used to control the drill string in advancing the borehole. The drilling rig also comprises pumps that circulate drilling fluid or drilling “mud” downward through the tubular drill string. The drilling mud exits through opening in the drill bit, and returns to the surface of the earth via the annulus defined by the wall of the borehole and the outer surface of the drill string. A mud motor is often disposed above the drill bit. Mud flowing through a rotor-stator element of the mud motor imparts torque to the bit thereby rotating the bit and advancing the borehole. The circulating drilling mud performs other functions that are known in the art. These functions including providing a means for removing drill bit cutting from the borehole, controlling pressure within the borehole, and cooling the drill bit.
In LWD/MWD systems, it is typically advantageous to place the one or more sensors, which are responsive to parameters of interest, as near to the drill bit as possible. Close proximity to the drill bit provides measurements that most closely represent the environment in which the drill bit resides. Sensor responses are transferred to a downhole telemetry unit, which is typically disposed within a drill collar. Sensor responses are then telemetered uphole and typically to the surface of the earth via a variety of telemetry systems such as mud pulse, electromagnetic and acoustic systems. Conversely, information can be transferred from the surface through an uphole telemetry unit and received by the downhole telemetry unit. This “down-link” information can be used to control the sensors, or to control the direction in which the borehole is being advanced.
If a mud motor is not disposed within the bottom hole assembly of the drill string, sensors and other borehole equipment are typically “hard wired” to the downhole telemetry unit using one or more electrical conductors. If a mud motor is disposed in the bottom hole assembly, the rotational nature of the mud motor presents obstacles to sensor hard wiring, since the sensors rotate with respect to the downhole telemetry unit. Several technical and operational options are, however, available.
A first option is to dispose the sensors and related power supplies above the mud motor. The major advantage is that the sensors do not rotate and can be hard wired to the downhole telemetry unit without interference of the mud motor. A major disadvantage is, however, that the sensors are displaces a significant axial distance from the drill bit thereby yielding responses not representative of the current position of the drill bit. This can be especially detrimental in geosteering systems, as discussed later herein.
A second option is to dispose the sensors immediately above the drill bit and below the mud motor. The major advantage is that sensors are disposed near the drill bit. A major disadvantage is that communication between the non rotating downhole telemetry unit and the rotating sensors and other equipment must span the mud motor. The issue of power to the sensors and other related equipment must also be addressed. Short range electromagnetic telemetry systems, known as “short-hop” systems in the art, are used to telemeter data across the mud motor and between the downhole telemetry unit and the one or more sensors. Sensor power supplies must be located below the mud motor. This methodology adds cost and operational complexity to the bottom hole assembly, increases power consumption, and can be adversely affected by electromagnetic properties of the borehole and the formation in the vicinity of the bottom hole assembly.
A third option is to dispose the one or more sensors below the mud motor and to hard wire the sensors to the top of the mud motor using one or more conductors disposed within rotating elements of the mud motor. A preferably two-way transmission link is then established between the top of the mud motor and the downhole telemetry unit. U.S. Pat. No. 5,725,061 discloses a plurality of conductors disposed within rotating elements of a mud motor, wherein the conductors are used to connect sensors below the mud motor to a downhole telemetry unit above the motor. In one embodiment, electrical connection between rotating and non rotating elements is obtained by axially aligned contact connectors at the top of the mud motor. This type of connector is known in the art as a “wet connector” and is used to establish a direct contact electrical communication link. In another embodiment, an electrical communication link is obtained using an axially aligned, non-contacting split transformer. The rotating and non rotating elements are magnetically coupled using this embodiment thereby providing the desired communication link.
SUMMARY OF THE INVENTION
This disclosure is directed toward LWD/MWD systems in which a mud motor is incorporated within the bottom hole assembly. More specifically, the disclosure sets forth apparatus and methods for establishing electrical communication between elements, such as sensors, disposed below the mud motor and a downhole telemetry unit disposed above the mud motor.
The bottom hole assembly terminates the lower end of a drill string. The drill string can comprise joints of drill pipe or coiled tubing. The lower or “downhole” end of the bottom hole assembly is terminated by a drill bit. An instrument subsection or “sub” comprising one or more sensors, required sensor control circuitry, and optionally a processor and a source of electrical power, is disposed immediately above the drill bit. The elements of the instrument sub are preferably disposed within the wall of the instrument sub so as not to impede the flow of drilling mud. The upper end of the instrument sub is operationally connected to a lower end of a mud motor. One or more electrical conductors pass from the instrument sub and through the mud motor and terminated at a motor connector assembly at the top of the mud motor. The mud motor is operationally connected to the electronics sub comprising an electronics sonde. This connection is made by electrically linking the motor connector assembly to a downhole telemetry connector assembly disposed preferably within an electronics sub. The electronics sonde element of the electronics sub can further comprise the downhole telemetry unit, power supplies, additional sensors, processors and control electronics. Alternately, some of these elements can be mounted in the wall of the electronics sub.
Several embodiments can be used to obtain the desired electrical communication link between the mud motor connector and the downhole telemetry connector assembly. As stated previously, this link connects sensors and circuitry in the instrument package with uphole elements typically disposed at the surface of the earth.
In one embodiment, a communication link is established between the mud motor connector and the downhole telemetry connector assemblies using an electromagnetic transceiver link. The axial extent of this transceiver link system is much less than a communications link between the instrument sub, and across the mud motor, to the telemetry sub, commonly referred to as a “short hop” in the industry. This, in turn, conserves power and is mush less affected by electromagnetic properties of the borehole environs. The transceiver communication link can be embodied as two-way data communication link. The transceiver link is not suitable for transmitting power downward to the sensor sub.
In another embodiment, a flex shaft is used to mechanically connect the rotor element of the mud motor to the lower end of the electronics sub. The flex shaft is used to compensate for this misalignment, with the upper end of the flex shaft being received along the major axis of the electronics sub. Stated another way, the flex shaft compensates, at the electronics sub, for any axial movement of the rotor while rotating. The one or more wires passing through the interior of the rotor are electrically connected to a lower toroid disposed around and affixed to the flex shaft. The lower toroid rotates with the rotor. An upper toroid is disposed around the flex shaft in the immediate vicinity of the lower toroid. Both the upper and lower toroids are hermetically sealed preferably within an electronics sonde. The upper toroid is fixed with respect to the non rotating electronics sonde thereby allowing the flex shaft to rotate within the upper toroid. Upper and lower toroids are current coupled through the flex shaft as a center conductor thereby establishing the desired two-way data link and power transfer link between the sensors below the mud motor and the downhole telemetry unit above the mud motor. The upper toroid is hard wired to the downhole telemetry element.
In still another embodiment, the flex shaft arrangement discussed above is again used. The upper, non rotating toroid is again disposed around the flex shaft as discussed previously. In this embodiment, the lower toroid is electrically connected to conductors passing through the rotor and is disposed near the bottom of the flex shaft and near the top of the mud motor. The lower toroid is hermetically sealed within the mud motor. The upper toroid is hermetically sealed within the electronics sub. The two-way data link and power transfer link is again established via current coupling by the relative rotation of the lower and upper toroids, with the flex shaft functioning as a center conductor.
In yet another embodiment, the conductors are electrically connected to axially displaced rings at or near the top of the flex shaft. The rings, which rotate with the stator and the flex shaft, are contacted by non rotating electrical contacting means such as brushes. The brushes are electrically connected to the downhole telemetry element within the electronics sonde of the telemetry sub. Other suitable non rotating electrical contacting means may be used such as conducting spring tabs, conducting bearings and the like. The desired communication link is thereby established between the mud motor and the electronics sub by direct electrical contact. This embodiment also permits two way data transfer, and also allows power to be transmitted from above the mud motor to elements below the mud motor. Power can also be transmitted downward through the mud motor to the instrument sub.
In still another embodiment, a lower and an upper magnetic dipole are used to establish a magnetic coupling link. The flex shaft used in previous embodiments is not required. This link is not suitable for the transfer of power.
BRIEF DESCRIPTION OF THE DRAWINGS
So that the manner in which the above recited features, advantages and objects the present invention are obtained and can be understood in detail, more particular description of the invention, briefly summarized above, may be had by reference to the embodiments thereof which are illustrated in the appended drawings.
FIG. 1 is a conceptual illustration of the major elements of the invention disposed in a well borehole;
FIG. 2 illustrates in more detail the elements of the bottom hole assembly of the invention;
FIG. 3 is a conceptual illustration of an electromagnetic transceiver link between the mud motor and electronics sonde of the bottom hole assembly;
FIG. 4 illustrates a data link embodiment that is based upon current coupling of sensors below a mud motor and a downhole telemetry unit above the mud motor;
FIG. 5 illustrates another data link embodiment that is based upon current coupling of sensors below a mud motor and a downhole telemetry unit above the mud motor;
FIG. 6 illustrates a data link using direct electrical contacts rather than current coupling;
FIG. 7 illustrates a data link using magnetic coupling;
FIG. 8 shows a borehole drilled by the bottom hole assembly and penetrating an oil bearing formation and bounded by non oil bearing formation;
FIG. 9 shows a log obtained from gamma ray and inclinometer sensors within said bottom hole assembly; and
FIG. 10 illustrates a pair of steam assisted gravity drainage (SAG-D) wells drilled using the geosteering and other features of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
This section of the disclosure will present an overview of the system, details of link embodiments, and an illustration the use of the system to determine one or more parameters of interest.
Overview of the System
FIG. 1 is a conceptual illustration of the major elements of the invention disposed in a well borehole 26 penetrating earth formation 24 . A bottom hole assembly, designated as a whole by the numeral 10 , comprises an instrument subsection or “sub” 12 , a mud motor 16 , and an electronics sub 18 . The instrument sub 12 is terminated at a lower end by a drill bit 14 and operationally connected at an upper end to a lower end of a mud motor 16 . The upper end of the mud motor 16 is operationally connected to a lower end of an electronics sub 18 . The upper end of the electronics sub 18 is operationally connected to a drill string 22 by means of a connector head 20 . The drill string 22 terminates at an upper end at a rotary drilling rig that is well known in the art and indicated conceptually at 30 . The drilling rig 30 cooperates with surface equipment 32 which typically comprises an uphole telemetry unit (not shown), means for determining depth of the drill bit 14 in the borehole 26 (not shown), and a surface processor (not shown) for combining sensor response from one or more sensors in the bottom hole assembly 10 with corresponding depth to form a “log” of one or more parameters of interest. Data are transfer between the electronics sub 18 and the uphole telemetry unit by telemetry systems known in the art including mud pulse, acoustic, and electromagnetic systems. This two-way data transfer is illustrated conceptually by the arrows 25 .
It is noted that the drill string 22 can be replaced with coiled tubing, and the drilling rig 30 replaced with a coiled tubing injector/extractor unit. Telemetry can incorporate conductors inside or disposed in the wall of the coiled tubing.
FIG. 2 illustrates in more detail the elements of the bottom hole assembly 10 . The drill bit 14 (see FIG. 1 ), which is received by the instrument bit box 36 , is not shown. Moving upward through the elements of the bottom hole assembly 10 , the instrument sub 12 comprises at least one sensor 40 and an electronics package 42 to control the at least one sensor 40 . A power supply 38 , such as a battery, powers the at least one sensor 40 and electronics package 42 in embodiments in which power can not be supplied by from sources above the mud motor 16 . The electronics package 42 typically comprise electronics to control the one or more sensors 40 , and a processor which processes, preprocesses, and conditions sensor response data for telemetering. The at least one sensor 40 and electronics package 42 are electrically connected to a lower terminus 44 of one or more conductors 46 that extend upward through the bottom hole assembly 10 . These conductors can be single strands of wire, twisted pairs, shielded multiconductor cable, coaxial cable and the like. Alternately, the conductors 46 can be optical fiber, with the instrument sub 12 comprising suitable elements (not shown) for convert electrical sensor response signals to corresponding optical signals. The one or more sensors 40 can be essentially any type of sensing or measuring device used in geophysical borehole measurements. These sensor types include, but are not limited to, gamma radiation detectors, neutron detectors, inclinometers, accelerometers, acoustic sensors, electromagnetic sensors, pressure sensors, and the like. An example of a log generated by a gamma ray detector and a measure of bottom hole assembly inclination will be presented in a subsequent section of this disclosure. When possible, elements of the instrument sub 12 are mounted within the sub wall so as not to impede the flow of drilling mud downward through the bottom hole assembly 10 .
Still referring to FIG. 2 , the instrument sub 12 is connected to a drive shaft 48 , which is supported within the bearing section of the mud motor 16 by radial bearings 50 and 54 , and by an axial bearing 52 . The drive shaft 48 is connected to a rotor 58 by a driver flex shaft 56 that transmits power from the rotor 58 to the drive shaft 48 . The driver flex shaft 56 is disposed in a bend section 57 of the mud motor thereby allowing the direction of the drilling to be controlled. The rotor 58 is rotated within a stator 60 by the action of the downward flowing drilling mud. The upper end of the rotor 58 terminates at a mud motor connector 62 . Conductors 46 , that extend from the lower terminus 44 through the drive shaft 48 and driver flex shaft 56 and rotor 58 , terminate at an upper terminus 66 within the mud motor connector 62 . The upper terminus 66 , like the lower terminus 44 and conductors 46 , rotate.
Again referring to FIG. 2 , an electronics sonde or insert 19 is disposed within the electronics sub 18 . FIG. 2 is conceptual and not to scale. The outside diameter of the electronics sonde 19 is sufficiently smaller than the inside diameter of the electronics sub 18 to form an annulus suitable for mud flow. This annulus is clearly shown at 21 in FIGS. 3-6 . The mud motor connector 62 rotatably couples the mud motor 16 to the electronics sub 18 and to the electronics sonde 19 therein through a downhole telemetry connector 64 . Mud flows through both the mud motor connector 62 and the downhole telemetry connector 64 . The downhole telemetry connector 64 comprises a telemetry terminus 70 that is electrically connected to elements within the electronics sonde 19 . These elements include a downhole telemetry unit 72 , optionally a power supply 74 , and optionally one or more additional sensors 76 of the types previously listed for the one or more instrument sub sensors 40 . The electronics sub 18 and electronics sonde 19 are operationally connected to the drill string 22 through the connector 20 , and two-way data transfer between the surface telemetry unit (not shown) and the downhole telemetry unit 72 is illustrated conceptually, as in FIG. 1 , by the arrow 25 .
Once again referring to FIG. 2 , a link between the rotating terminus 68 and the non rotating terminus 70 is illustrated by the broken line 68 . The following section will detail several embodiments of this link, which allows response of sensors 40 disposed on the downhole side of the mud motor 16 to be transmitted to the surface of the earth thereby allowing the sensors to be disposed in close axial proximity to the drill bit 14 .
It is noted that some embodiments do not use a mud motor connector 62 and a downhole telemetry connector 64 , with the corresponding terminuses 66 and 70 . Other embodiments use variations of the arrangement shown in FIG. 2 . The discussion of each linking embodiment will include details of the link connections.
Link Embodiments
In the context of this disclosure, the term “operational coupling” comprises data transfer, power transfer, or both data and power transfer.
An electromagnetic transceiver link between the mud motor 60 and electronics sonde 19 is shown conceptually in FIG. 3 . The conductor 46 , shown here as a twisted pair of wires, is again disposed within the rotor 58 and terminates at the terminus 66 within the mud motor connector 62 . The terminus is hard wired to a lower transceiver 80 disposed within the mud motor connector 62 . As in FIG. 2 , the mud motor connector 62 is rotatably attached to the downhole telemetry connector 64 , which is attached to the lower end of the electronics sub 18 . The downhole telemetry connector 64 contains an upper transceiver 82 hard wired to the terminus 70 . The downhole telemetry unit 72 disposed within the electronics sonde 19 is hard wired to the terminus 70 . Data are transmitted to and from the downhole telemetry unit 72 and the surface, as indicated conceptually with the arrow 25 . The transceiver link, two-way electromagnetic data link between the upper and lower transceivers 82 and 84 , respectively, is indicated conceptually by the broken line 68 . As stated previously, elements within the downhole telemetry connector 64 and the mud motor connector 62 are disposed to allow drilling mud to flow through. It should be noted that power can also be transmitted to elements within the instrument sub, or alternatively these elements must be powered by a source 38 (see FIG. 2 ) such as a battery.
FIG. 4 illustrates a data link embodiment that is based upon current coupling of sensors below the mud motor and the downhole telemetry unit above the mud motor. Elements and functions of this embodiment will be discussed beginning at the bottom of the illustration. As in the previous embodiment, the conductors 46 leading from the instrument sub 12 are shown as a twisted pair disposed within the rotor 58 . The conductors pass through feed throughs 66 A and 66 B, that are somewhat analogous to the terminus structure 66 shown in FIGS. 2 and 3 . The conductors 46 terminate at a lower toroid 92 that surrounds and rotates with a flex shaft 90 . The lower toroid is hermetically sealed from the mud flow by a sealing means such as a rubber boot 99 . As stated previously, the flex shaft essentially compensates for axial movement of the rotor, when rotating, with respect to the electronics sub.
Still referring to FIG. 4 , the flex shaft extends 90 upward through a pressure housing 97 through a sealing element 96 , and is supported by a radial bearing 98 that provides a conductive path to the electronics sonde housing 19 . An upper toroid 94 surrounds the upper end of the flex shaft 90 . The upper toroid 94 is stationary with respect to the rotating flex shaft 90 . Leads from the upper toroid 94 pass through feed throughs 70 A and 70 B (which are roughly analogous to the terminus 70 in FIGS. 2 and 3 ) and connect to the downhole telemetry unit 72 disposed in the electronics sonde 19 . Data and/or power are transmitted to and from the downhole telemetry unit 72 as illustrated conceptually by the arrow 25 .
Again referring to FIG. 4 , the upper and lower toroids 94 and 92 rotate with respect to one another thereby forming a current coupling via the flex shaft 90 functioning as a center conductor. It should be understood that, within the context of this disclosure, relative rotation of the upper and lower toroids 92 and 94 also comprises the previously discussed axial movement component of the lower toroid with respect to the upper toroid. The upper end of the flex shaft 90 is electrically connected through the radial bearings 98 to casing of the mud motor 60 , which is electrically connected to the rotor 58 through the axial bearings 52 (see FIG. 2 ), which electrically connected to the lower end of the flex shaft 90 thereby completing the conduction circuit. An upward data link is obtained by applying a data current signal, such as a response of a sensor 40 (see FIG. 2 ), to the lower toroid 92 . A corresponding data current signal is induced in the upper toroid 94 , via the previously described current loop, and telemetered to the surface via the downhole telemetry unit 72 . Conversely, data can be transmitted to the instrument sub 12 from the surface. This “down-link” data are telemetered from the surface telemetry unit contained in the surface equipment 32 to the downhole telemetry unit 72 , converted within the electronics sonde 19 to a current and applied to the upper toroid 94 . A corresponding current induced in the lower toroid 92 that is carried to the instrument sub via the conductors 46 . The two-way current coupled link is shown conceptually by the broken lines 68 . The current link may also be used to transfer power from a source contained in the downhole telemetry unit 72 to the instrument sub 12 in FIG. 2
As mentioned previously, the mud motor connector, downhole telemetry connector, and terminus structure shown in FIG. 4 has been modified in the link embodiment. Axial elements within by the broken line 62 A are roughly analogous to mud motor connector and associated terminus. Axial elements within the broken line 64 A are roughly analogous to the downhole telemetry connector and associated terminus.
FIG. 5 illustrates another embodiment of a data link that is based upon current coupling of sensors below the mud motor and the downhole telemetry unit above the mud motor. Elements and functions of this embodiment will again be discussed beginning at the bottom of the illustration. The lower end of the flex shaft 90 is attached to the rotor 58 by means of a flange 49 , and the upper end of the flex shaft 90 extends through a seal 106 and into the electronics sonde 19 . Conductors 46 leading from the instrument sub 12 are again shown as a twisted pair disposed within the rotor 58 and the flex shaft 90 . The conductors pass through feed through 114 in the wall of the flex shaft 90 and are attach to a lower toroid 92 that surrounds and rotates with a flex shaft 90 . A lower electrical conducting radial bearing 108 supports the flex shaft below the lower toroid 92 .
Still referring to FIG. 5 , the flex shaft 90 extends upward through an upper toroid 94 , which is fixed with respect to the electronics sonde 19 . The upper toroid 94 is supported by an electrical conducting upper radial bearing 110 disposed above the upper toroid 94 . The upper toroid 94 is stationary with respect to the rotating flex shaft 90 . Leads from the upper toroid 94 pass through feed throughs 70 A and 70 B and connect to the downhole telemetry unit 72 disposed in the electronics sonde 19 . Data are transmitted to and from the downhole telemetry unit 72 as illustrated conceptually by the arrow 25 . Note that the upper and lower toroids 94 and 92 , and the upper and lower bearings 110 and 108 , are all disposed within the electronics sonde 19 .
Again referring to FIG. 5 , the upper and lower toroids 94 and 92 rotate with respect to one another thereby forming a current coupling via the flex shaft 90 that functions as a center conductor. The upper end of the flex shaft 90 is electrically connected through the upper radial bearings 110 to housing of the electronics sonde 19 , which is electrically connected to the flex shaft 90 through the lower radial bearing 108 , which electrically connected to the lower end of the flex shaft 90 thereby completing the conduction circuit. As in the previous embodiment, an upward data link is obtained by applying a data current signal, such as a response of a sensor 40 (see FIG. 2 ), to the lower toroid 92 . A corresponding data current signal is induced in the upper toroid 94 , via the previously described current loop, and telemetered to the surface via the downhole telemetry unit 72 . Conversely, data can be transmitted to the instrument sub from the surface. The data are telemetered to the downhole telemetry unit 72 , converted within the electronics sonde 19 to a current and applied to the upper toroid 94 . A corresponding current induced in the lower toroid 92 , which is carried to the instrument sub via the conductors 46 . The two-way current coupled link is again shown conceptually by the broken lines 68 .
FIG. 6 illustrates a data link using direct electrical contacts rather than current coupling. The lower end of the flex shaft 90 is attached to the rotor 58 by means of a flange 49 , and the upper end of the flex shaft 90 extends through a seal 120 and into a pressure housing 122 . Conductors 46 leading from the instrument sub 12 are once again shown as a twisted pair disposed within the rotor 58 and the flex shaft 90 . The conductors are terminated at a lower and upper conductor rings 128 and 126 , respectively. The upper and lower conductor rings are electrically insulated from one another and from the flex shaft 90 , and rotate with the flex shaft. The flex shaft 90 is supported by a radial bearing 124 disposed below the lower conducting ring 128 . It has been previously noted that the number of conductors can vary. A conductor ring is provided for each conductor.
Still referring to FIG. 6 , the upper and lower conductor rings 126 and 128 are electrically contacted by upper and lower brushes 129 and 130 that are fixed with respect to the electronics sonde 19 . Leads from the from the upper and lower brushes 129 and 130 pass through feed throughs 134 and 132 , respectively, and electrically connect with the downhole telemetry unit 72 disposed within the electronics sonde 19 . Data are transmitted to and from the downhole telemetry unit 72 as illustrated conceptually by the arrow 25 . As stated above, the number of conductors can vary. A conductor ring and a cooperating brush are provided for each conductor.
FIG. 7 illustrates still another embodiment of a data link that is based upon magnetic coupling of sensors below the mud motor and the downhole telemetry unit 72 above the mud motor. A lower and an upper magnetic dipole, represented as a whole by 220 and 210 , respectively, are used to establish the link. The flex shaft used in previous embodiments has been eliminated. Elements and functions of this embodiment will again be discussed beginning at the bottom of the illustration. The lower dipole 220 is attached to the rotor 58 , and comprises a ferrite element 204 surrounding a steel mandrel 200 . Wires 218 are wound around the circumference of the ferrite element 205 and connect through feed through 212 to conductors 46 emerging from the rotor 58 .
Still referring to FIG. 7 , the upper dipole 210 is attached to the electronic sonde 19 , and comprises a ferrite element 205 surrounding a steel mandrel 202 . Wires 221 are wound around the circumference of the ferrite element 205 and connect through feed throughs 222 to the downhole telemetry unit 72 disposed in the electronics sonde 19 . Data are transmitted to and from the downhole telemetry unit 72 as illustrated conceptually by the arrow 25 .
Again referring to FIG. 7 , the upper and lower dipoles 210 and 220 rotate with respect to one another thereby forming a magnetic coupling illustrated conceptually by the broken curves 230 . The magnetic filed generated by the lower dipole 220 is indicative of the response of elements of the instrument sub 12 , such responses of a sensor 40 (see FIG. 2 ). This magnetic field induces a corresponding data current signal is in the upper dipole 210 , which is typically telemetered to the surface via the downhole telemetry unit 72 . Conversely, data can be transmitted to the instrument sub 12 from the surface via the same magnetic link. The link illustrated in FIG. 7 is not suitable for the transfer of power.
Applications
Two MWD/LWD geophysical steering applications of the system are illustrated to emphasize the importance of disposing the instrument sub 12 as near as possible to the drill bit 14 . It is again emphasized that the system is not limited to geosteering applications, but can be used in virtually any LWD/MWD application with one or more sensors disposed in the instrument sub 12 . In applications where the axial displacement between sensors and the drill bit is not critical, additional sensors can be disposed within the electronics sonde 19 or in the wall of the electronics sub 18 . These applications include, but are not limited to, LWD type measurements made when the drill string is tripped.
For purposes of geosteering illustration, it will be assumed that the one or more sensors 40 in the instrument sub 12 comprise a gamma ray detector and an inclinometer. Using the response of these two sensors, the position of the bottom hole assembly 10 in one earth formation can be determined with respect to adjacent formations. Gamma radiation and inclinometer data are telemetered to the surface in real time using previously discussed methodology thereby allowing the path of the advancing borehole to be adjusted based upon this information. Some processing of the sensor responses can be made in one or more processors disposed within elements of the bottom hole assembly 10 where the information is decoded by appropriate data acquisition software.
FIG. 8 shows a borehole 26 penetrating several earth formations. As shown, the bottom hole assembly 10 , operationally attached to the drill string 22 , is advancing the borehole 26 in an oil bearing formation 140 . The objective of the drilling operation is to advance the borehole 26 within the oil bearing formation 140 , as shown, thereby maximizing hydrocarbon production from this formation. As illustrated in FIG. 8 , the oil bearing formation 142 is relatively thin, and bounded by “floor” and “ceiling” formations 144 and 142 at bed boundaries 152 and 143 , respectively. Natural gamma radiation levels in oil bearing formations are typically low. Oil bearing formations are typically bounded by shales, which exhibit high natural gamma ray activity. For purposes of illustration, it will be assumed that the oil bearing formation 140 is low in gamma ray activity, and the bounding “floor” and “ceiling” formations 144 and 142 , respectively, that are shales exhibiting relatively high levels of natural gamma radiation.
FIG. 9 is a “log” of a measure of natural gamma ray intensity (ordinate), depicted as the solid curve 160 , as a function of depth (abscissa) along the borehole 26 . The broken curve 166 of FIG. 9 illustrates a log of the inclination bottom hole assembly 10 , as measured by the inclinometer sensor, as a function of depth. Downward vertical is arbitrarily denoted as −180 degrees, and horizontal is denoted as 0 degrees. As will be discussed below, this log information is telemetered in real time to the surface thereby allowing drilling direction changes to be made quickly in order to remain within the target formation.
Referring to both FIGS. 8 and 9 , the borehole is within the ceiling shale formation 142 at a depth 149 , and the borehole 26 is near vertical. This is represented on the log of FIG. 9 at depth 149 A as a maximum gamma radiation reading and an inclinometer reading of about −180 degrees. As the borehole enters the oil bearing formation 140 as indicated by a decrease in gamma radiation, the borehole is diverged from the vertical by the driller in order to remain within this target formation. At 150 of FIG. 8 , it can be seen that the borehole is near the center of the formation 140 , and the inclination is about −90 degrees. This location is reflected in at depth 150 A in the log of FIG. 9 by minimum gamma radiation intensity and an inclination of approximately −90 degrees. Between 150 and 152 of FIG. 8 , it can be seen that the borehole is approaching the bed boundary 152 of the floor formation 144 by the driller. The gamma ray detector senses the close proximity of the formation, and is reflected as an increase in gamma radiation at a depth 152 A of the FIG. 9 log. This alerts the driller-that the borehole is approaching floor formation, and the drilling direction must be altered to near horizontal so that the bottom hole assembly 10 remains within the target zone 140 . The broken curve 166 indicates at 152 A that the borehole is near horizontal. As seen in FIG. 8 , the borehole 26 is essentially horizontal between 152 and 154 , but is approaching the bed boundary 143 of the ceiling formation 142 . This is sensed by the gamma ray detector and is reflected in an increase in gamma radiation that reaches a maximum at depth 154 A. This increase is observed in real time by the driller. As a result of this real time observation, the drilling direction is adjusted downward between 153 and 154 until a decrease in gamma radiation below depth 154 A indicates that the bottom hole assembly 10 is once again being directed toward the center of the target formation. This change in inclination is reflected In FIG. 9 by the broken curve 166 at a depth between 153 A and 154 A.
To summarize, the system can be embodied to steer the drilling operation and thereby maintain the advancing borehole within a target formation. In this application, where directional changes are made based upon sensor responses, it is of great importance to dispose the sensors as close as possible to the drill bit. As an example, if the sensor sub were disposed above the mud motor, the floor formation 144 could be penetrated at 152 before the driller would receive an indication of such on the gamma ray log 160 . The present system permits sensors to be disposed as close a two feet from the drill bit.
The drill bit-sensor arrangement of the invention is also very useful in the drilling of steam assisted gravity drainage (SAG-D) wells. SAG-D wells are usually drilled in pairs, as illustrated in FIG. 10 . The drilling system and cooperating bottom hole assembly 10 are typically used to drill the curve and lateral sections of the first well borehole 26 A. Using the geosteering methodology discussed above, this borehole is drilled within the oil bearing formation 140 but near the bed boundary 141 of the floor formation 144 . Once the borehole 26 A is completed, a magnetic ranging tool 165 is disposed within the borehole 26 A. The second well borehole 26 B drilled with a magnet sensor as one of the sensors 40 used in the sensor sub 12 (see FIG. 2 ) of the bottom hole assembly 10 . The magnetic sensor responds to the location of the magnetic ranging tool 165 in borehole 26 A and is, therefore, used to determine the proximity of the borehole 26 B relative to the borehole 26 A. The borehole pairs are typically drilled within close proximity to one another, with tight tolerances in the drilling plan, in order to optimize the oil recovery from the target formation 140 . Steam is pumped into the upper borehole 26 B, which heats oil in the target formation 140 causing the viscosity to decrease. The low viscous oil then migrates downward toward the lower borehole 26 A where it is collected and pumped to the surface.
To summarize, the effective drilling SAG-D wells require sensors to be disposed as close as possible to the drill bit in order to meet the tight tolerances of the drilling plan.
One skilled in the art will appreciate that the present invention can be practiced by other that the described embodiments, which are presented for purposes of illustration and not limitation, and the present invention is limited only by the claims that follow. | Apparatus and methods for establishing electrical communication between an instrument subsection disposed below a mud motor and an electronics sonde disposed above the mud motor in a drill string conveyed borehole logging system. Electrical communication is established via at least one conductor disposed within the mud motor and connecting the instrument sub section to a link disposed between the mud motor and the electronics sonde. The link can be embodied as a current coupling link, a magnetic coupling ling, an electromagnetic telemetry ling and a direct electrical contact link. Two way data transfer is established in all link embodiments. Power transfer is also established in all but the electromagnetic telemetry link. | 4 |
BACKGROUND
[0001] The present invention relates generally to rotating electric machinery and, more particularly, to a method and system for protecting voltage regulator driver circuitry during a field coil short circuit condition.
[0002] Generators are found in virtually every motor vehicle manufactured today. These generators, also referred to as alternators, produce electricity necessary to power a vehicle's electrical accessories, as well as to charge a vehicle's battery. Generators must also provide the capability to produce electricity in sufficient quantities so to power a vehicle's electrical system in a manner that is compatible with the vehicle's electrical components. The alternator or generator typically uses a voltage regulator to regulate the charging voltage and output current in order to provide consistent operation during varying loads that would otherwise create voltage drops and other operational problems. Presently, conventional vehicle charging systems may utilize a voltage regulator having either a discrete transistor or, alternatively, a custom integrated circuit known as an Application Specific Integrated Circuit (ASIC).
[0003] Still other vehicle designs may also employ voltage regulators with advanced microprocessor functions that maintain a highly accurate regulated voltage produced by a generator. Microprocessor based regulators may also include advanced clock and memory circuits that store battery and power supply reference data, battery voltage and generator rotation speed, as well determine how much the battery is being charged and at what rate at any point in time.
[0004] In operation of a vehicle alternator, it is possible that the field coil used to generate the magnetic field of the rotor portion of the alternator may become short-circuited. In such a case, the voltage regulator driver circuitry should be deactivated in order to discontinue the flow of field current through the driver devices until such time as the short circuit condition is cleared. Conventionally, such short circuit protection (when provided at all) involves use of a number of components, such as (for example) a small shunt resistance within the field coil path and an analog voltage comparator to determine whether the voltage across the shunt resistor exceeds a nominal voltage when the field coil is not short circuited. Accordingly, it would be desirable to be able to provide short circuit protection for voltage regulator driver circuitry in a manner that results in fewer hardware components and/or reduced component costs.
SUMMARY
[0005] The foregoing discussed drawbacks and deficiencies of the prior art are overcome or alleviated by, in an exemplary embodiment, a method for protecting voltage regulator driver circuitry during a short circuit condition of an alternator field coil, including passively detecting a drop in field coil voltage during an on-portion of a duty cycle of the field coil voltage, wherein the passive detection of the drop in field coil voltage signifies an interrupt event; and responsive to the interrupt event, changing a logical state of a driver enable control signal so as to deactivate driver circuitry associated with a switching device used to pass field current through the field coil, wherein the driver circuitry, when deactivated, prevents the switching device from passing current regardless of the state of a pulse width modulation (PWM) control signal applied to the driver circuitry.
[0006] In still another embodiment, a storage medium includes a computer readable computer program code for protecting voltage regulator driver circuitry during a short circuit condition of an alternator field coil, and instructions for causing a computer to implement a method. The method further includes passively detecting a drop in field coil voltage during an on-portion of a duty cycle of the field coil voltage, wherein the passive detection of the drop in field coil voltage signifies an interrupt event; and responsive to the interrupt event, changing a logical state of a driver enable control signal so as to deactivate driver circuitry associated with a switching device used to pass field current through the field coil, wherein the driver circuitry, when deactivated, prevents the switching device from passing current regardless of the state of a pulse width modulation (PWM) control signal applied to the driver circuitry.
[0007] In still another embodiment, a voltage regulator for an electrical generator includes an electronic device configured to compare an output voltage of the generator to a desired set point voltage thereof, driver circuitry in communication with the electronic device, the driver circuitry configured to selectively activate and deactivate a switching device used to pass field current through a field coil, in response to a difference between the output voltage and the desired set point voltage; one or more components configured to passively detect a drop in field coil voltage during an on-portion of a duty cycle of the field coil voltage, wherein the passive detection of the drop in field coil voltage signifies an interrupt event; and the electronic device further configured to protect the driver circuitry and switching device during a field coil short circuit condition by changing a logical state of a driver enable control signal, responsive to the interrupt event, so as to deactivate the driver circuitry and prevent the switching device from passing current regardless of the state of a pulse width modulation (PWM) control signal applied to the driver circuitry.
[0008] In still another embodiment, a vehicle charging system includes an alternator having one or more stator windings on a stationary portion thereof and a field coil on a rotatable portion thereof. A voltage regulator is configured to regulate an output voltage of the alternator through control of a field current through the field coil. The voltage regulator further includes an electronic device configured to compare an output voltage of the alternator to a desired set point voltage thereof; driver circuitry in communication with the electronic device, the driver circuitry configured to selectively activate and deactivate a switching device used to pass field current through the field coil; one or more components configured to passively detect a drop in field coil voltage during an on-portion of a duty cycle of the field coil voltage, wherein the passive detection of the drop in field coil voltage signifies an interrupt event; and the electronic device further configured to protect the driver circuitry and switching device during a field coil short circuit condition by changing a logical state of a driver enable control signal, responsive to the interrupt event, so as to deactivate the driver circuitry and prevent the switching device from passing current regardless of the state of a pulse width modulation (PWM) control signal applied to the driver circuitry.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] Referring to the exemplary drawings wherein like elements are numbered alike in the several Figures:
[0010] FIG. 1 is a schematic diagram of an exemplary vehicle charging system employing a microprocessor based voltage regulator, suitable for use in accordance with an embodiment of the invention;
[0011] FIG. 2 is a more detailed schematic diagram of the voltage regulator shown in FIG. 1 ;
[0012] FIG. 3 is a more detailed schematic diagram of the voltage regulator of FIGS. 1 and 2 , illustrating a method for protecting voltage regulator driver circuitry during a field coil short circuit condition, in accordance with an embodiment of the invention; and
[0013] FIG. 4 is a waveform diagram depicting an exemplary operating scenario of the protection circuitry shown in FIG. 3 .
DETAILED DESCRIPTION
[0014] Disclosed herein is a method and system for protecting voltage regulator driver circuitry during a field coil short circuit condition. Briefly stated, a voltage regulator (e.g., microprocessor based) is configured with the capability of sensing a field coil short circuit condition through a simple (resistor/diode) combination of passive components, and thereby generating an interrupt signal that disables the driver circuitry associated with the field coil. Further, when implemented at least in part in software, the present techniques do not require more expensive hardware (e.g., differential amplifiers) configured within the ECM and/or voltage regulator.
[0015] Referring initially to FIG. 1 , there is shown a schematic diagram of an exemplary vehicle charging system 100 employing a microprocessor based voltage regulator, suitable for use in accordance with an embodiment of the invention. It should be appreciated that although FIG. 1 depicts a vehicle charging system, the present embodiments are applicable to other types of regulated generator systems. A vehicle alternator 101 has a plurality of windings 102 (e.g., three-phase, delta configuration) in a stator portion thereof, and a field coil 104 in a rotor portion thereof. The alternating current (AC) voltage generated in the windings 102 is converted to a direct current (DC) voltage by a full-wave rectifier 106 , which in turn includes three diode-pairs configured in parallel. The DC output of the rectifier 106 is fed to the positive terminal of a vehicle battery 108 , wherein the magnitude of the output voltage is dependent upon the speed of the rotor and the amount of field current supplied to the field coil 104 .
[0016] In certain alternator designs, the stator may actually include independent pairs of stator windings and an associated pair of rotor field coils to reduce noise in view of increased load escalation. However, for purposes of simplicity, only one set of stator windings and field coil is illustrated. It will also be appreciated that the windings 102 could alternatively be connected in a Y-configuration having a common neutral point.
[0017] As further illustrated in FIG. 1 , a voltage regulator 110 is utilized to regulate and control the magnitude of the output voltage generated by the alternator 101 , and thus control the (direct current) charging voltage applied to the battery 108 and associated vehicle loads (e.g., load 112 connected through switch 114 ). It does so by controlling the magnitude of field current supplied to field coil 104 through high-side alternator terminal “F+” shown in FIG. 1 . Additional details concerning the generation of current through the field coil 104 by regulator 110 are discussed in further detail hereinafter.
[0018] One skilled in the art may also recognize other standardized terminals associated with the alternator, including: the high-side battery output terminal “B+”, the phase voltage terminal “P” used to monitor the AC output voltage of the alternator; and the ground terminal “E” used to provide a ground connection for the alternator. An electronic control module 116 (ECM), which may represent the vehicle's main computer, receives a charge warning lamp signal through lamp terminal “L” of the regulator 110 , used to control a charge warning lamp 118 when ignition switch 120 is closed. The ECM 116 also receives a rotor switching signal through terminal “F m ”, indicative of the field current signal F+ applied to the field coil 104 .
[0019] Referring now to FIG. 2 , a more detailed schematic diagram of at least portions of the voltage regulator 110 of FIG. 1 is illustrated. For purposes of simplification, various discrete electronic components (e.g., resistors, capacitors, etc.) of the regulator 110 are not depicted in FIG. 2 . A microcontroller 122 having control logic code therein receives feedback of the alternator charging system voltage(s) in digital form through an internal analog-to-digital converter (ADC) configured therein. Based on a comparison between the sensed system voltage and a predetermined set operating voltage of the system, the microcontroller generates a PWM output signal (PWM_DC) that is coupled to a high-side driver 124 . The high-side driver 124 in turn provides a pulsed switching signal to the control terminal (e.g., gate) of transistor 126 . Based on the duty cycle of the pulsed signal, the on/off switching of transistor causes field current to intermittently flow through field coil 104 . During “off” periods of the duty cycle, energy within the field coil is dissipated through a flyback diode 128 .
[0020] As indicated above, the regulator 110 attempts to maintain a predetermined charging system voltage level (set point). When the charging system voltage falls below this point, the regulator 110 increases the level of field current by increasing the duty cycle of the PWM_DC current. Conversely, when the charging system voltage increases above the system set point, the 110 decreases the level of field current by decreasing the duty cycle of the PWM_DC current.
[0021] As further indicated above, it is possible for the field coil 104 to become short-circuited during operation of the alternator 101 due to, for example, the presence of metal shavings in the rotor. Accordingly, FIG. 3 is a more detailed schematic diagram of the voltage regulator shown in FIGS. 1 and 2 , illustrating a system and method for protecting voltage regulator driver circuitry during a field coil short circuit condition, in accordance with an embodiment of the invention. From a hardware perspective, a simple resistor/diode combination is used to passively detect a field coil short circuit condition, combined with the use of internal microprocessor software to generate a command that deactivates the high-side driver 124 .
[0022] More specifically, a resistor R 1 is configured in series between the high-side alternator terminal F+ and an input pin of the microcontroller 122 , designated as “Interrupt” in FIG. 3 . In addition, a diode D 1 is configured between the PWM output pin (PWM_DC) of the microcontroller 122 and the “Interrupt” input pin, wherein a forward biasing of the diode D 1 couples the voltage on the PWM_DC output pin to the “Interrupt” input pin of the microcontroller 122 . Under normal operating conditions, the output signal on PWM_DC has the same duty cycle, but opposite phase, as the output voltage of the field coil. A logical low signal applied to the input of the high-side driver 124 in turn drives the gate of an N-channel MOSFET device 126 high. The high-side driver 124 is thus “active low” in that the transistor 126 is rendered conductive when the output voltage of the PWM_DC pin is logical low (e.g., 0 volts), assuming that the high-side driver is actively enabled in the first place. In this regard, a “Driver Enable” output signal of the microcontroller 122 is coupled to the high side driver 124 through a resistor R 2 , which selectively activates or deactivates the high-side driver 124 , depending on whether or not normal operating conditions exist.
[0023] So long as normal operating conditions exist, the voltage on the “Interrupt” input pin of the microcontroller 122 remains at logic high, and the internal logic and/or software of the microcontroller 122 maintains the “Driver Enable” output signal at active low. On the other hand, during a short circuit of the field coil 104 (indicated by the dashed line 130 in FIG. 3 ), the voltage on the “Interrupt” input pin of the microcontroller 122 transitions to logic low due to the short. The internal logic and/or software of the microcontroller 122 detects a falling edge transition of the “Interrupt” pin voltage, and switches the “Driver Enable” output signal logic high, thereby disabling the high-side driver 124 and preventing any field current from flowing through the transistor 126 until such time as the short circuit condition is cleared.
[0024] FIG. 4 is a waveform diagram depicting an exemplary operating scenario of the protection circuitry shown in FIG. 3 . As is shown, the four waveforms depicted in FIG. 4 are the PWM_DC output signal of the microcontroller 122 , the field output voltage at F+, the voltage of the “Interrupt” input pin of the microcontroller 122 , and the voltage of the “Driver Enable” output pin of the microcontroller 122 . Prior to time t 1 , the regulator is in a normal operating condition, in that there is no short circuit condition across the field coil 104 . During the “off” portions of the PWM_DC duty cycle, the field output voltage is high, which in turn keeps the voltage at the “Interrupt” pin at high. Moreover, during the “on” portions of the PWM_DC duty cycle (when the field output voltage is low), the voltage at the “Interrupt” pin at still maintained at logic high, notwithstanding the discharged voltage at F+, due to the combination of D 1 and R 1 . So long as the microcontroller 122 does not detect a falling transition of the logical high voltage at the “Interrupt” input pin, it will maintain the “Driver Enable” output pin at an active low logic level.
[0025] However, at time t 1 , a short circuit condition now exists across the field coil 104 , so as to result in the field output voltage immediately falling to 0 volts. Because this coincides with the “off” portion of the duty cycle of PWM_DC, there is no signal voltage present on PWM_DC that would allow R 1 and D 1 from preventing the voltage at the “Interrupt” input pin from discharging to logic low. Consequently, the microcontroller 122 switches the “Driver Enable” signal from logic low to logic high, thereby deactivating the high-side driver 124 .
[0026] Between time t 1 and t 2 , it will be noted that the next “on” portion of the PWM_DC duty cycle is reached. Correspondingly, the voltage on the “Interrupt” pin is at least temporarily restored to logic high. However, this brief rise is not yet enough information for the microcontroller 120 to determine whether the short circuit condition has been eliminated because the field coil voltage would nominally be 0 at this point in the duty cycle, even under normal conditions. Accordingly, assuming that the short circuit condition still exists by the next “off” portion of the PWM_DC duty cycle at time t 2 , FIG. 4 further illustrates a falling edge in input voltage of the “Interrupt” pin and a brief pulse in the output voltage at F+, coinciding with the transition of the PWM_DC signal to low. This represents a short circuit attempt at pulling down the “Interrupt” pin voltage through the resistor (R 1 ) coupling with PWM_DC. However, the voltage coupled to the “Interrupt” pin is quickly discharged through R 1 and the shorted out field coil 104 . Therefore, because the voltage at the “Interrupt” pin was not maintained during the “off” portion of the PWM_DC duty cycle, the microcontroller 120 does not restore the “Driver Enable” output pin to active low logic level at this point.
[0027] It is then assumed that the short circuit condition is cleared by time t 3 , corresponding to the next “off” portion of the duty cycle of PWM_DC. At this point, the voltage at the “Interrupt” pin is still maintained high immediately after PWM_DC goes low, since the field coil is no longer shorted out and can prevent current from instantaneously discharging the “Interrupt” pin voltage. The microcontroller 122 therefore detects this condition and resets the “Driver Enable” signal back to active low so that the high-side driver 124 can turn on transistor 126 , passing current through the field coil 104 and generating the output voltage thereon.
[0028] Although the exemplary method and system outlined above is depicted as being implemented in software within the microcontroller 122 , one skilled in the art will also appreciate that the logic can also be implemented through hardware configured within an ASIC type regulator, for instance. In view of the above, the present method embodiments may therefore take the form of computer or controller implemented processes and apparatuses for practicing those processes. The disclosure can also be embodied in the form of computer program code containing instructions embodied in tangible media, such as floppy diskettes, CD-ROMs, hard drives, or any other computer-readable storage medium, wherein, when the computer program code is loaded into and executed by a computer or controller, the computer becomes an apparatus for practicing the invention.
[0029] While the invention has been described with reference to a preferred embodiment or embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims. | A method for protecting voltage regulator driver circuitry during a short circuit condition of an alternator field coil includes passively detecting a drop in field coil voltage during an on-portion of a duty cycle of the field coil voltage, wherein the passive detection of the drop in field coil voltage signifies an interrupt event. Responsive to the interrupt event, a logical state of a driver enable control signal is changed so as to deactivate driver circuitry associated with a switching device used to pass field current through the field coil, wherein the driver circuitry, when deactivated, prevents the switching device from passing current regardless of the state of a pulse width modulation (PWM) control signal applied to the driver circuitry. | 7 |
CROSS REFERENCE TO RELATED APPLICATION(S)
This application claims priority to German Application No. 10 2013 223 105.9, filed Nov. 13, 2013. The entirety of the disclosure of the above-referenced application is incorporated herein by reference.
BACKGROUND OF THE INVENTION
Field of the Invention
The present invention relates to motor vehicle beams, such as longitudinal beams and/or crossbeams. The present invention relates in particular to crossbeams formed as bumper beams, a term which is frequently used in the relevant field of expertise.
Description of the Related Art
In the case of motor vehicles, there is often the technical problem of supplying cooling air to units arranged within functional regions surrounded by portions of bodywork. This applies for example to the engine compartment, which inter alia is surrounded by the engine cover and the wing and into which cooling air can generally be fed through a radiator grille, which is at the front in the direction of travel, in order to cool units such a coolant heat exchanger and the like.
Technical solutions are known here for providing a vehicle component with a through-flow opening which can be opened or indeed closed to different degrees by adjustable flaps for the passage of air. Air flap systems of this type can achieve, on one hand, low-emission, rapid heating of the internal combustion engine and, on the other hand, adequate convective cooling of units.
Recently, engineers and designers have been increasingly attempting to utilise the available installation space in a motor vehicle as efficiently as possible, and this has led to units and connection means in the motor vehicle, in particular in the engine compartment, being considerably condensed. This could lead to a situation in which although air flaps of an air flap system uncover a through-flow opening through which cooling air flows, this cooling air only reaches the units to be cooled to a limited extent, since additional components or assemblies of the motor vehicle may be arranged in the flow path from the air flap system to the unit to be cooled, which components or assemblies divert or block off the air flow passing through the through-flow opening in part or the units to be cooled in full.
A possible solution thereto could be an air-guiding device arranged downstream of the air flaps in the flow direction, which device guides cooling air passing through the through-flow opening in a targeted manner to the points at which convective cooling is required. However, this leads to another assembly needing to be arranged in a functional space in the motor vehicle.
The problem addressed by the present invention is therefore that of providing technical teaching that makes it possible to guide cooling air in a targeted manner to the points at which it is required for convectively cooling functional parts and functional assemblies, without increasing the number of components required therefor.
SUMMARY OF THE INVENTION
This problem is solved according to the invention by a motor vehicle beam of the type mentioned at the outset, which is formed as a hollow component having a closed cross section adapted for conducting gas, in particular air.
By means of the solution according to the invention, a component which is already provided on the motor vehicle is configured for guiding gas, generally air. Air-guiding ducts therefore do not need to be separately manufactured and mounted in the vehicle, to the extent to which gas, generally air, can be guided through crossbeams and/or longitudinal beams of the motor vehicle to the points which require convective cooling. Even if the point which requires convective cooling is remote from the point at which the gas guided within the beam exits said beam, the complexity of the air-guiding apparatus required outside the motor vehicle beam that guides the gas is considerably reduced.
The closed cross section allowing gas to be guided is crucial for the motor vehicle beam to conduct gas in its longitudinal direction, the cavity within said cross section forming a duct-like air-guiding space in the motor vehicle beam. To produce a hollow motor vehicle beam of this type more easily, it is advantageous for said beam to comprise a plurality of shell components which, when interconnected, surround a gas-guiding duct.
To make it easier to shape at least one shell component, it is preferable for a shell component to be formed as a plastics shell component and to include plastics material as a material, and preferably to be formed therefrom. A plastics shell component formed in this manner may be a deep-drawn component, or may preferably be produced as an injection-moulded component having a large design scope for the three-dimensional shape of the shell component.
Generally, the motor vehicle beam serves to lend stability to the vehicle in which it is installed, in particular also in the event of collisions. In order to prevent the function of the plastics shell component being impaired in the event of minor collisions, according to a development of the present invention it is preferable for the plastics shell component to be arranged on the side of the motor vehicle beam that faces the vehicle interior when fully mounted, and for it to preferably form the side of the motor vehicle beam that faces the vehicle interior. In this respect, the side of the motor vehicle beam that faces outwards, that is to say away from the vehicle, is preferably formed by a shell component other than the plastics shell component when fully mounted. This component can be formed so as to have higher strength and stability or rigidity than the plastics shell component, so that the plastics shell component itself remains intact if the motor vehicle beam according to the invention suffers a minor impact. Since collisions generally affect the vehicle from the outside, the inwardly facing arrangement of the plastics shell component is preferred. However, it should not be ruled out that the shell component arranged on the side of the motor vehicle beam that points towards the vehicle interior when fully mounted is made of metal, in particular steel, in part or in full.
In pursuit of the aim already set out above of forming the shell component so as to have increased strength and stability or rigidity, an additional shell component, which differs from the above-mentioned plastics shell component, may be made of metal and/or of fibre-reinforced and/or mat-reinforced and/or particle-reinforced plastics material. This shell component having increased stability and rigidity can at least comprise materials of this type. The first-mentioned embodiment is therefore referred to as the “metal shell component”, whereas the second-mentioned embodiment is referred to as the “reinforced plastics shell component”. Steel, the material that has proven successful in motor vehicle construction, in particular deep-drawable sheet steel, is preferred as the metal.
Although it may be considered that the shell component having increased stability and rigidity may be made of different metals, for example in portions, or of metal and reinforced plastics material, it is however preferred that the shell component having increased stability and rigidity can be produced in as few operations as possible, preferably in one operation, and therefore is substantially only made of one material.
In order to protect the plastics component connected to the shell component having increased stability and rigidity, for example in the event of minor collisions, for the above-mentioned reasons it is preferable for the shell component having increased stability and rigidity to be arranged on the side of the motor vehicle beam that faces outwards when fully mounted, and for said shell component to preferably form the side of the motor vehicle beam that faces outwards, away from the vehicle interior. The side that points towards the vehicle interior is a side of the motor vehicle beam that faces inwards when the vehicle is fully assembled. On the basis of the design of the motor vehicle beam, in particular on the basis of the curvature of a crossbeam, a person skilled in the art can also determine, without observing the motor vehicle beam on the fully assembled vehicle, which side of the motor vehicle beam faces outwards, away from the vehicle interior, and which side faces inwards, towards the vehicle interior when fully mounted.
To produce the motor vehicle beam according to the invention in the simplest and thus most cost-effective manner possible, it may be provided that it is formed from two shell components, that is to say from precisely two shell components. Preferably, said shell components are the above-mentioned plastics shell component and the shell component having increased stability and rigidity. Said shell components may be interconnected in an interlocking manner and/or with a force fit and/or in an integrally bonded manner. In this case, gluing together the two shell components falls explicitly within the meaning of an integrally bonded connection. Therefore, shell components made of different materials can also be integrally bonded to one another. In order to interconnect the shell components in a particularly robust and rigid manner, said shell components are both interconnected in an interlocking and an integrally bonded manner.
In order not only to make it possible to guide gas through the motor vehicle beam but also for it to be possible to control the amount of gas that is guided, at least one flow flap which can be moved relative to the motor vehicle beam is provided thereon and/or therein.
For example, the motor vehicle beam may comprise at least one gas inlet, through which gas can enter the cavity surrounded by the closed cross section of the motor vehicle beam from outside the motor vehicle beam. Likewise, the motor vehicle beam may comprise a gas outlet, from which gas guided within the motor vehicle beam can exit said beam again. Preferably, the gas inlet and gas outlet are remote from each other in the longitudinal direction of the motor vehicle beam.
In principle, it may be considered that one longitudinal end of the motor vehicle beam serves as the gas inlet and the opposite longitudinal end serves as the gas outlet. However, when the preferred crossbeam is the gas-guiding motor vehicle beam, it can only be designed in such a way with difficulty. In order in particular to form a crossbeam for conducting gas, it may be provided that the at least one gas inlet is formed as an opening which penetrates a side wall of the motor vehicle beam, preferably in the region of the longitudinal centre thereof, more preferably on the outwardly pointing side thereof. In the case of a front motor vehicle beam, the outwardly pointing side thereof is the front side thereof that points in the forward direction of travel when the motor vehicle bearing said beam is in operation.
The above-mentioned alternatives of a flow flap provided on the motor vehicle beam can be implemented in that the at least one gas inlet and/or the at least one gas outlet is provided with the adjustable flow flap, which can be adjusted between a closed position in which a gas flow cross section through the gas inlet and/or the gas outlet is minimal, preferably zero, and an open position in which the gas flow cross section through the gas inlet and/or the gas outlet is larger than in the closed position so that a gas flow through the gas inlet and/or the gas outlet is surely possible, and preferably the gas flow cross section through the gas inlet and/or the gas outlet is at the maximum. Preferably, the flow flap is provided on the gas inlet and prevents gas from entering the gas-guiding motor vehicle beam. Alternatively or additionally, said flap may be provided on the gas outlet and prevent gas from exiting the gas-guiding motor vehicle beam.
In order to simplify the assembly of the flow flap, said flap may be part of a flap module, comprising a frame defining a gas-flow opening and the flow flap arranged on the frame so as to be adjustable relative thereto. The flap module can then be preassembled as an assembly.
Furthermore, an actuator for adjustably actuating the flow flap is preferably provided in order to adjust the flow flap between the closed position and the open position, optionally with intermediate positions and preferably in a continuous manner. This actuator, for example an electromotor, an electromagnet or a pneumatic or hydraulic drive, may also be part of the flap module.
Above all, it is advantageous to configure a flap module as an assembly, in particular as a preassembled assembly, when the flow flap is intended to be provided on the shell component having increased stability and rigidity, for example on a gas inlet opening thereof. The flap module may be made of plastics material and have a high degree of design freedom, in particular at least the majority of the components thereof may be formed as plastics injection-moulded parts. The flap module may thus be made of a material that differs from the material of the shell component that bears said module. Again, it is the case that the flap module can be fixed to the shell component bearing said module in an interlocking manner and/or with a force fit and/or in an integrally bonded manner. In this case, it may also be sufficient to provide an opening in the shell component having increased stability and rigidity as a gas inlet opening, and to mount the flap module therein.
Alternatively or additionally, the at least one flow flap may also be provided in the motor vehicle beam. In this case, above all, the plastics shell component that can be designed with a high degree of design freedom is preferred as a support for a flow flap, rather than the shell component having increased stability and rigidity. Therefore, according to a development of the present invention, it may be provided that at least one flow flap surrounded by the fully mounted motor vehicle beam is arranged on the plastics shell component and can be moved between a blocking position in which a gas flow cross section through the motor vehicle beam is minimal, preferably zero, and a passage position in which the gas flow cross section through the motor vehicle beam is greater than in the blocking position, so that a gas flow through the motor vehicle beam is possible in a safe manner, and preferably the gas flow cross section through the motor vehicle beam is at the maximum.
Generally, the at least one flow flap can be pivoted between its positions about a pivot axis. If the flow flap is arranged in the motor vehicle beam, in this case it is preferable for the pivot axis to be oriented in a vertical direction orthogonal to the longitudinal direction and to the depth direction of the motor vehicle beam, since this requires the shortest adjustment path.
It may for example be advantageous for the flow flap to be arranged in the motor vehicle beam if, starting from a gas inlet arranged in the longitudinal centre, gas is only intended to be guided in one of the two portions of the motor vehicle beam which start from the gas inlet, in particular if gas is intended to be guided on different sides of the gas inlet in different portions at different times.
When a flow flap is pivotally arranged in the motor vehicle beam, a pivot shaft of the flow flap can be guided through the wall of the motor vehicle beam, in particular of the plastics shell component, so that an actuator can be connected to the part of the shaft positioned outside the motor vehicle beam, for example via a crank arm.
When the flow flap is arranged on the motor vehicle beam, the pivot axis can be oriented as desired. In particular at the gas inlet, it is preferable for the pivot axis to be oriented parallel to the longitudinal direction of the motor vehicle beam in order to achieve a flow of gas into the motor vehicle beam that is as uniform as possible in the longitudinal direction of the motor vehicle beam (in the case of a crossbeam, this is the transverse direction of a vehicle bearing said beam). Preferably, the gas inlet opening is positioned at the longitudinal centre of the crossbeam in order to ensure that inflowing gas is distributed as evenly as possible towards both longitudinal ends.
In order to form the motor vehicle beam according to the invention to have the highest possible rigidity, it is preferable, when installed in a vehicle, for said beam to extend in its longitudinal direction mainly in the transverse direction of the vehicle, in its vertical direction mainly in the vertical direction of the vehicle and in its depth direction mainly in the longitudinal direction of the vehicle, the motor vehicle beam having a tapered region in the region of its vertical centre, which tapered region has smaller dimensions in the depth direction than regions positioned thereabove or therebelow in the vertical direction and preferably extends over substantially the entire length of the motor vehicle beam.
BRIEF DESCRIPTION OF THE DRAWING FIGURES
The present invention is explained in greater detail in the following with reference to the accompanying drawings, in which:
FIG. 1 is a perspective view of a motor vehicle beam according to the invention in the form of a crossbeam, in front of which a radiator grille is arranged and behind which further vehicle units are arranged,
FIG. 2 is a front view of the crossbeam from FIG. 1 ,
FIG. 3 is a sectional view through the crossbeam along line III-III in FIG. 2 , and
FIG. 4 is a plan view of the crossbeam from FIGS. 1 to 3 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 is a perspective view of a crossbeam 10 as an embodiment according to the invention of a motor vehicle beam of the present application. In order to show how it is arranged on a vehicle, an irregularly oval-shaped radiator grille 12 that is positioned in front of the crossbeam 10 when fully mounted is shown and components 14 positioned behind the crossbeam 10 are shown.
The longitudinal end of the crossbeam 10 which is on the right in FIG. 1 is not shown. The crossbeam 10 is shown with a sketched, zigzag edge on the right-hand longitudinal end thereof.
FIG. 2 is a front view of the crossbeam 10 from FIG. 1 , that is to say a view in which an observer is standing in front of the vehicle bearing the crossbeam 10 .
Fastening elements 16 , 18 and 20 serve to mount additional structural elements on the crossbeam 10 .
In FIG. 2 , said observer is looking from the front at a shell component 22 having increased stability and rigidity, which is preferably produced from metal, in particular steel, in a deep-drawing process.
The metal shell component 22 having increased stability and rigidity is provided so as to point outwards, that is to say so as to point away from the vehicle interior, when the crossbeam 10 is fully mounted on the vehicle.
In order to increase the rigidity of the shell component 22 , it is provided with a bead 24 extending in the longitudinal direction L of the crossbeam 10 .
The bead 24 is preferably offset to one side in the vertical direction H of the crossbeam in a portion containing the longitudinal central region of the crossbeam 10 , and in the present case is offset downwards, for example to create space for a gas inlet opening 26 . The bead 24 may, however, also extend differently to the way in which it is shown.
An assembly 28 made up of a frame 30 and a flow flap 32 that is received pivotally about a pivot axis S on the frame 30 is preferably inserted into the gas inlet opening 26 . Said pivot axis S advantageously extends approximately parallel to the longitudinal direction L of the crossbeam 10 . The assembly 28 is advantageously bonded via the frame 30 to the shell component 22 in the region surrounding the gas inlet opening 26 and engages behind the edge of the shell component 22 surrounding the gas inlet opening 26 , for example by means of resilient latching lugs. The frame 28 and, together therewith, the flow flap 30 are thus provided on the shell component 22 in an interlocking and integrally bonded manner.
By means of an actuator (not shown in FIG. 2 ), the flow flap 32 can be adjusted between the closed position shown in FIG. 2 in which a gas flow opening 34 that is surrounded by the frame 30 is completely closed and an open position in which the surface area of the gas flow opening 34 through which gas can flow is at the maximum.
The actuator may be an electromotor, an electromagnet or a pneumatically or hydraulically operable piston-cylinder assembly. The flow flap can be biased into an end position by pre-adjusting springs.
When the flow flap 32 is not in its closed position shown in FIG. 2 , air passes through the gas flow opening 34 owing to the movement of the vehicle relative to the surrounding atmosphere when the vehicle bearing the crossbeam 10 is travelling in a straight line, and is distributed approximately equally towards the right-hand longitudinal end 10 a and the left-hand longitudinal end 10 b of the crossbeam 10 owing to the preferred arrangement of the gas inlet opening 26 in the longitudinal centre. The gas flow is indicated by double-line arrows.
FIG. 3 is a cross section through the crossbeam 10 along line III-III from FIG. 2 . It can be seen that a plastics shell component 36 made of plastics material is provided on the side of the crossbeam 10 that points towards the vehicle interior when fully mounted, which plastics shell component defines a cavity 38 together with the metal shell component 22 , which cavity forms an air-guiding duct within the crossbeam 10 . For the purposes of increased inherent stability, the plastics shell component 36 is also preferably configured to have a bead 40 extending in the longitudinal direction L of the crossbeam 10 .
The shell components 22 and 36 are interconnected in a bonded manner, and they are also preferably interconnected in an interlocking manner, for example by clipping or locking into place. For this purpose, corresponding latching lugs can be formed in the preferably injection-moulded plastics shell component 36 .
The parting plane or joint plane between the shell components 22 and 36 is preferably in the centre in the depth direction, at the point denoted F.
The way in which the joining point extends can be seen well in FIG. 4 in the plan view of the crossmember 10 .
In addition to or as an alternative to the flow flap 32 , a further flow flap 42 may also be provided within the crossbeam 10 , for example as an asymmetrical butterfly flap 42 , as can be seen in FIG. 3 in the upper part of the cavity 38 .
The flow flap 42 that is substantially symmetrical to the vertical centre in the vertical direction H may be rotatable about a rotational axis D which is defined by shaft ends 42 a which penetrate the plastics material of the plastics shell component 36 . The shaft ends 42 are preferably integrally formed with the flow flap 42 . An actuator for rotatably adjusting the flow flap 42 may be coupled to the portion of the shaft end 42 a located outside the crossbeam 10 .
At the longitudinal ends 10 a and 10 b thereof, the crossbeam 10 may be coupled to longitudinal beam portions 44 and 46 , which also form cavities, so that air flowing within the crossbeam 10 at the longitudinal ends 10 a and 10 b thereof can overflow into the longitudinal beam portions 44 and 46 .
The beads 24 and 40 in the shell components 22 and 36 cause the cavity 38 in the crossbeam 10 to be constricted in the depth direction T.
In the gas outlet openings on the side of the crossbeam 10 that points towards the vehicle interior, gas can exit the cavity 38 in the crossbeam 10 and enter the longitudinal beam portions 44 and 46 . Said portions can in turn comprise gas outlet openings, from which the gas, generally air, flowing into the gas inlet opening 26 can exit at a point requiring convective cooling.
Using the present invention, for example cooling air can thus be guided from a longitudinally central region of the crossbeam 10 which, when fully mounted, approximately coincides with a region in the transverse centre of the vehicle to the longitudinal end regions 10 a and 10 b of the crossbeam and onwards from here to points that require cooling, without specific air-guiding means being required therefor. Instead, the air-guiding function is integrated in beams 10 and optionally 44 and 46 of a motor vehicle that are already provided. | The present invention relates to a motor vehicle beam, such as a longitudinal beam and/or a crossbeam, in particular a bumper beam, wherein the motor vehicle beam is formed as a hollow component having a closed cross section for the passage of gas, in particular air. | 8 |
TECHNICAL FIELD
The present invention relates to a method for recycling residues having an elevated content of zinc and sulfates. It relates more particularly to a method for processing residues arising from a neutral or weakly acidic leaching step during the hydrometallurgical extraction of zinc. These residues mainly comprise zinc ferrite (ZnFe 2 O 4 ) and compounds in the form of sulfates.
BRIEF DISCUSSION OF RELATED ART
Extractive metallurgy for zinc involves subjecting sphalerite or blende, an impure ore containing zinc in the form of zinc sulfide (ZnS), to oxidising roasting at a temperature of between 910 and 980° C., the primary aim of which is to convert the sulfides into oxides. The resultant calcine mainly comprises zinc oxide (ZnO) and some compounds in the form of oxides and optionally of sulfates. In the subsequent leaching steps, the calcine is treated with a low-concentration sulfuric acid solution with the aim of extracting the zinc therefrom. The zinc extracted into the liquid phase is then subjected to a purification step before undergoing electrolysis.
The residue arising from the leaching operation still contains a significant quantity of complexed zinc, mainly in the form of insoluble zinc ferrites created during the roasting operation. This residue also contains metals such as silver (Ag), germanium (Ge), indium (In), etc.
In the conventional hydrometallurgical approach, dissolving the zinc ferrites in the residues arising from the leaching operation entails using concentrated and/or heated acidic solutions having an H 2 SO 4 concentration of between 50 and 200 g/L. A method of this type is described in U.S. Pat. No. 4,415,540. A significant proportion of the complexed zinc can be recovered in this manner. However, decomplexing the ferrites brings about dissolution of the iron in the form of iron oxide together with many other impurities. The removal of iron is the aim of many hydrometallurgical methods, typical residues of which arising from the precipitation of iron by hydrolysis are haematite, goethite, paragoethite or jarosite. Due to the risk of leaching of the heavy metals present in these residues, it is not possible to avoid storing them in leak-proof, controlled areas. Increasingly stringent environmental requirements result in elevated storage costs, so calling the economic viability of these methods into question.
The method of U.S. Pat. No. 4,072,503 describes a pyrometallurgical method for treating residues created during the hydrometallurgical extraction of zinc. The material is firstly heated under non-reducing conditions with introduction of O 2 in order to break down the sulfides and sulfates. The desulfurised material containing the metal oxides is then reduced by addition of a reducing agent in a quantity such that the lead and zinc are reduced, but not the iron, which is eliminated in the slag. The reactors may be an elongate furnace with immersed electrodes or a rotary furnace.
A recent pyrometallurgical method (WO2005005674) proposes recovering non-ferrous metals such as Cu, Ag, Ge and Zn present in the residues originating from the hydrometallurgical extraction of zinc by a two-step method combining a multi-stage furnace and a submerged lance furnace. In the first reactor, the metal oxides present in the residues processed are pre-reduced with the assistance of coke. The fumes collected at the furnace outlet contain inter alia Pb and Zn. The pre-reduced material is then introduced into the second reactor, where it undergoes an oxidising smelting stage. During this step, the iron is eliminated with the slag in the form of FeO and Fe 2 O 3 . Copper and silver are extracted in the liquid phase. Finally, the collected fumes contain germanium together with the remainder of the zinc and lead still present in the product. This method makes it possible to recover a large proportion of the non-ferrous metals, but a very significant quantity of slag containing more than 30% Fe is produced: more than 650 kg per tonne of residues processed. However, this slag can only be recycled if it is stabilised and used in the construction sector. Recycling of the slag therefore directly depends on the demand for raw materials in this sector. Furthermore, high-temperature operation of the multi-stage furnace in a reducing environment results in a significant formation of accretions and clogging, resulting in very costly furnace maintenance and reduced availability of the facility.
Economic recycling of residues having an elevated content of iron and zinc, such as electric furnace dusts, is possible thanks to the PRIMUS® direct reduction method, based on the reduction smelting method described in WO2002/068700. Processing leaching residues by this method is associated with problems due to the elevated sulfur content. This is because the presence of such a quantity of sulfur inhibits the transfer of pre-reduced carbon into the cast iron. Furthermore, an elevated content of sulfur makes the cast iron unusable.
SUMMARY
The disclosure proposes an alternative solution to existing methods for treating residues having an elevated content of zinc and sulfates, in particular originating from the hydrometallurgical extraction of zinc.
This is achieved by a method for treating residues comprising zinc ferrites and non-ferrous metals selected from among the group made up of lead (Pb), silver (Ag), indium (In), germanium (Ge) and gallium (Ga) or mixtures thereof in the form of oxides and sulfates, comprising the following stages:
a) roasting of the residues in an oxidising environment at elevated temperature in order to obtain a desulfurised residue, b) carburising reduction smelting of the desulfurised residue in a reducing environment, c) liquid phase extraction of carburised cast iron and slag, d) vapour phase extraction of the non-ferrous metals, followed by the oxidation and recovery thereof in the solid phase.
The residues used in the method advantageously originate from the hydrometallurgical extraction of zinc, in particular from a neutral or weakly acidic leaching step for zinc ores.
The three recoverable products arising from this method are therefore a carburised cast iron, a stable and inert slag usable for the manufacture of cement or as ballast and a mixture of oxides in pulverulent form containing non-ferrous metals such as zinc, lead, silver, indium and germanium, gallium (Zn, Pb, Ag, In, Ge, Ga).
The method has the advantage of enabling virtually complete recycling of the residues, including iron, so satisfying both environmental and economic requirements due to the recovery of non-ferrous metals, in particular zinc. In addition to the recovery of non-ferrous metals, the method makes it possible to recover the iron content in the residues in an economic manner while simultaneously reducing the quantity of slag formed. Furthermore, the slag obtained has a composition close to that of a blast furnace slag and may consequently be recycled in the same way.
Advantageously, a step a1) comprising carbon-based pre-reduction in the solid state of the iron oxides is inserted between step a) and step b). This pre-reduction in step a1) is preferably carried out at a temperature of between 800 and 900° C.
In accordance with another advantageous embodiment, the roasting of step a) and the pre-reduction of step a1) are carried out in a multi-stage furnace in which desulfurisation of the residues in an oxidising environment at elevated temperature (between 1000 and 1100° C.) is performed in the upper stages and the pre-reduction at low temperature in the lower stages. Using a multi-stage furnace enables thorough mixing of the compounds, so making desulfurisation effective at lower temperature with desulfurisation being appreciable from as low as 900° C. and almost complete at 1000° C. The literature cites distinctly higher temperatures for roasting sulfates in elongate furnaces.
The purpose of pre-reduction step a1) is to partially reduce the metal oxides, while minimising the reduction of zinc, which is performed in the smelting furnace. Pre-reduction in step a1) requires the addition of a carbon-containing reactant, preferably a coal with a high volatile content. The reduction in temperature from approximately 1000° C. to 1100° C. to below 900° C. is achieved by introducing the carbon-containing reducing agent. This carbon-containing reducing agent is not preheated before being introduced into the multi-stage furnace; its moisture content is preferably between 10 and 20%.
Carburising reduction smelting of the desulfurised residue in a reducing environment is preferably carried out in a plasma arc electric furnace. The heel is preferably vigorously stirred by injecting an inert gas (nitrogen, argon) through the furnace bottom, this being carried out for three reasons:
to equalise the temperature of the metal bath and the slag, to renew the surface of the slag layer in order to permit absorption of the treated material without the latter solidifying and forming an impenetrable crust, to increase entrainment extraction of non-ferrous metals in the gases.
The non-ferrous metals which may be extracted by the method are inter alia zinc, lead, silver, indium, germanium, gallium (Zn, Pb, Ag, In, Ge, Ga). If the residues contain copper, the majority of this is extracted in the liquid phase with the cast iron.
Silver is more difficult to extract due to its high vapour pressure. It is nevertheless possible to vaporise a large proportion of it by working at a higher temperature and by increasing the stirring flow rate for the cast iron bath. Typically, the temperature of a cast iron bath in an electric furnace is around 1,500° C. and the stirring flow rate between 80 and 120 L/min·t. If a temperature of above 1,550° C. with a stirring flow rate of between 100 and 300 L/min·t is used, the silver extraction yield is then greater than 90%.
DETAILED DESCRIPTION
According to a first preferred embodiment, the method according to the invention may be performed in two separate reactors. The first reactor is for example a conventional rotary furnace, where the residue is desulfurised. This desulfurised residue is then introduced with the anthracite which is necessary for reduction and carburisation into an electric furnace operated at a temperature of the order of 1,500° C. However, this approach would seem to be of little economic interest, on the one hand due to the significant quantity of fossil energy (gas/fuel oil) required for roasting and on the other hand due to the high cost of anthracite and likewise high electricity consumption.
One option for reducing costs involves replacing the anthracite with a lower cost reducing agent, specifically a coal with a high volatile content (>30%). “Steam coals” comprising 50 to 55% fixed C, 35 to 40% volatile compounds and 7 to 10% ash will typically be used.
In such a case, an intermediate step for devolatilising the coal and pre-reducing the iron oxides is then added. This step has two advantages over the first embodiment. On the one hand, pre-reduction of the iron oxides saves the electrical energy required to reduce them in the electric furnace. On the other hand, the heat arising from combustion of the excess gas produced by the carbon-containing reactant is utilised to meet the heat requirements for drying and desulfurising the material. Pre-reduction is carried out at a temperature of between 850° C. and 900° C. in order to achieve a degree of metallisation of the iron of from 20 to 40%. Coal is introduced in a quantity sufficient to provide an excess of free carbon necessary for complete reduction of the metal oxides in the electric furnace.
According to another preferred embodiment, the desulfurisation step and the pre-reduction step are carried out in two separate rotary furnaces in order to ensure better control of temperatures and the countercurrent reaction media. The volatile compounds and the hot gases of the pre-reduction reactor are used to heat the desulfurisation reactor. Air is injected to ensure combustion of the volatile compounds, postcombustion of the gases and oxidising conditions in the reaction environment.
Other characteristics and advantages will be revealed by the detailed description of an advantageous embodiment which is provided below by way of illustration with reference to the attached drawing, in which:
FIG. 1 is a schematic diagram of an installation which permits the implementation of the method according to the invention.
In this FIGURE, reference numeral 10 denotes a multi-stage furnace, reference numeral 12 an electric arc furnace and reference numeral 14 an installation for treating the fumes originating from both the multi-stage furnace and the electric furnace.
Before being introduced into multi-stage furnace 10 via the duct 16 , the residues are preferably granulated or pelletised and pre-dried to facilitate handling.
The desulfurisation step a) proceeds in the upper stages 18 . The lower stages 20 are dedicated to devolatilising the coal which is introduced via the duct 22 and to pre-reducing the iron oxides (step a1)). The volatile compounds and hot gases are used as an energy source in the upper stages 18 , where the oxidising atmosphere is maintained by injecting excess air into the upper stages 18 .
On leaving the multi-stage furnace 10 , the solid product which has been desulfurised and pre-reduced, being at a temperature of approximately 800° C. to 900° C., is conveyed to the electric arc furnace 12 .
It is possible for it to contain a small proportion of sulfur bound to calcium in the form of CaSO 4 . However, this sulfur is not troublesome during production of the cast iron, because it is eliminated in the form of CaS with the slag.
The outlet gases from the multi-stage furnace 10 discharged via the duct 24 contain a relatively small quantity of dusts which were suspended during charging of the material into the reactor. The dusts are conveyed to the fume treatment installation 14 where they are mixed with the pulverulent oxides of step d).
This mode of operation of the furnace with high temperatures in the upper stages and low temperatures in the lower stages is original to the extent that it is the opposite of the usual mode of operation of a multi-stage furnace.
Stages b), c) and d) proceed simultaneously in the same reactor.
Step b) of the method is actually the combination of two phenomena:
complete reduction of the metal oxides by a carbon-containing reducing agent, smelting of a metal bath vigorously stirred by addition of an inert gas, such as nitrogen (N 2 ) or argon (Ar).
The products resulting from this second step are a carburised cast iron ( 26 ), a slag ( 28 ) containing the main elements of the gangue and gases ( 30 ) mainly comprising carbon monoxide and carbon dioxide. These gases furthermore have a content of metallic compounds in vapour form. The collected gases join the same fume treatment line as the gases produced during step a).
The zinc and other metals are recovered in the form of a pulverulent product ( 32 ), made up of oxides and optionally sulfates when the compounds have recombined with the SO x produced during step a).
In a preferred embodiment, the method therefore involves two reactors. The first reactor is a multi-stage furnace in which the upper stages are dedicated to the desulfurisation of the product in an oxidising environment at elevated temperature and the lower stages to the pre-reduction of the iron at low temperature with the introduction of volatile coal at this level. The second reactor is a plasma arc electric furnace in which the final reduction and smelting stages proceed together with the extraction of non-ferrous metals.
Other distinctive features and characteristics of the invention will be revealed by the detailed description of an advantageous embodiment given below by way of illustration.
Example 1
Desulfurisation in an Oxidising Environment
An experimental study carried out in the laboratory demonstrated the feasibility of thermally decomposing the sulfated compounds from weakly acidic leaching. The analytical results are presented in Table 1.
Description of Test Installation
The test installation comprises a single-hearth laboratory furnace fitted with a gas treatment line. This furnace provides a batch simulation of the method of a continuous multi-hearth furnace, i.e. the progression of the continuous metallurgical phenomena. The laboratory furnace has an internal diameter of 500 mm. It is heated by means of electric heating elements located in the roof. On the central shaft there are mounted two diametrically opposed arms each supporting a pair of teeth oriented in opposing directions. Continuous stirring is thus ensured without any accumulation of material along the furnace wall. Gas injection through a duct into the furnace enclosure makes it possible to establish and maintain an atmosphere suited to the requirements of the test, this being achieved independently of the temperature setting. The gases formed during the oxidation/reduction reactions are collected in a postcombustion chamber, where any combustible compounds are burnt. The gases are subsequently cooled, then filtered, before being discharged into the atmosphere via a flue.
Description of Tests
Batch tests performed with 6.0 kg of leaching residues mainly made up of zinc ferrite (ZnO.Fe 2 O 3 ), lead sulfate (PbSO 4 ), calcium sulfate (CaSO 4 ), zinc sulfate (ZnSO 4 ) and impurities such as SiO 2 , MgSO 4 , Al 2 O 3 , CuSO 4 were carried out in the enclosure described above. The material is granulated, then pre-dried to facilitate handling and transport. It is then introduced at ambient temperature into the furnace preheated to 1050° C. The oxidising atmosphere in the furnace enclosure is maintained by injecting air at a constant flow rate. A test lasts 60 minutes. The speed of rotation of the central shaft is a constant 3 rpm. Product temperature is measured regularly with the assistance of a thermocouple. In parallel with the measurement, a sample of the material is taken and then cooled with liquid nitrogen. The sample is finely ground, then analysed.
Results
The starting residue contains 5.01% S. Analyses reveal that 70% of the material is desulfurised in 15 min. After 60 min, the level of desulfurisation of the residue is 95%. The small quantity of S (0.24%) still present in the material is apparently bound to Ca in the form of CaSO 4 . Thermal decomposition of the sulfates results in the release of SO 3 and SO 2 , which are collected in the fume treatment line. These collected gases are mainly composed of SO N , H 2 O, N 2 and O 2 .
The quantity of lead and zinc is identical before and after the tests, which allows the conclusion to be drawn that, at elevated temperature, in an oxidising environment, lead and zinc are not volatilised.
The aims of the first step are largely achieved with a desulfurisation rate of greater than 95% for a temperature of 1050° C. The limiting factor for treatment of the residue in the smelting furnace is a sulfur content of greater than 0.5%. The study has shown that temperature has a direct influence on the level of product desulfurisation. A person skilled in the art will straightforwardly be able to adjust the temperature and dwell time as a function of the intended degree of desulfurisation.
Example 2
Pre-Reduction of Iron Oxides
The experimental study was continued to demonstrate the feasibility of pre-reducing the iron oxides present in the acidic leaching residue. The reducing agent is a coal with a high volatile content containing 55% fixed carbon. The analytical results are presented in Table 1.
The test device is the same as described in Example 1.
The weakly acidic leaching residue which has been desulfurised in an oxidising atmosphere is kept in the laboratory furnace enclosure. 2.2 kg of wet coal are added and mixed into the material thanks to the continuous stirring. This quantity corresponds to a ratio of 300 kg per 1 t of residue. Air injection was previously stopped. The purpose of nitrogen injection at a constant flow rate is to prevent any introduction of interfering air so as to protect the reducing atmosphere. The water present in the coal is evaporated. The flame observed in the postcombustion chamber is due to the combustion of the carbon monoxide produced on reduction of the iron oxides. A test lasts one hour, during which the temperature of the material is regularly measured. Again using the operating method described in Example 1, samples are taken in parallel with these measurements and then analysed.
Results
The iron oxides present in the residue are partially reduced. The iron phases present in the pre-reduced material are wustite (FeO) and metallic iron (Fe). The gas mixture collected in the fume treatment line is mainly composed of H 2 O, CO, CO 2 , N 2 and O 2 . The proportions of each gas vary as a function of the kinetics of the reactions involved.
At 1,000° C., the level of metallisation is greater than 90%. Experience shows, however, that it is frequently preferable to operate at 900° C. This is because very rapid metallisation of iron at the surface results in the granules sticking together in “bunches”. At 900° C., the level of metallisation is less than 75%, but remains satisfactory to ensure the economic viability of an industrial installation.
It should be noted that coal is an additional source of sulfur, which explains the larger quantity of sulfur in the pre-reduced material than in the desulfurised residue. However, this quantity is low and has no impact on yield nor on the quality of the finished products.
Example 3
Final Reduction and Smelting
This example describes a reduction smelting test of the pre-reduced material, a weakly acidic leaching residue which has previously been dried and desulfurised. The products leaving the smelting furnace are a carburised cast iron containing copper, an inert slag composed of the main constituents of the gangue and the fumes containing numerous metals in the form of gas or dust. Oxidation, cooling and filtration of these compounds proceed in the fume treatment line.
Description of Test Installation and Smelting Method
The installation is an electric arc furnace equipped with a gas treatment line comparable to that in the first furnace. The furnace has a diameter of 2.5 m and can contain 6 t of cast iron. The material is gravity charged, at a constant flow rate, into the central zone of the furnace. The arc makes it possible to heat the bath to the desired temperature. The smelting carried out is of the PRIMUS® type with a bath strongly stirred by pneumatic gas injection (N 2 ). The slag is discharged via a door provided for this purpose, the cast iron via the taphole. The dust-laden gases are collected in the fume treatment line. A postcombustion chamber converts the CO into CO 2 and combusts other combustible compounds and cools the gases by adding excess air. Before being released into the atmosphere, the gases pass through a bag filter where dusts are recovered.
Description of Test
The purpose of the test is to determine the distribution coefficient of the various elements, in particular of the recoverable metallic elements such as Zn, Pb, Ag, Ge, by analysis of the cast iron, the slag and the dusts produced.
The desulfurised and partially reduced weakly acidic leaching residue is introduced at a constant flow rate into the electric furnace containing a cast iron bath necessary for formation of the electric arc. The bath is maintained at a temperature of 1,500° C. for several hours. Continuous measurement of the carbon content makes it possible to monitor that the test is proceeding properly from the standpoint of the method. A sample is taken every half an hour with the assistance of a manipulator. The material sampled is then analysed. The basicity of the slag is adjusted with an additive to ensure good fluidity.
Results
The cast iron obtained is composed of 93.5% Fe, 4% C, 2.5% Cu and a few traces of other elements.
The slag contains the principal elements of the gangue: essentially SiO 2 , CaO, Al 2 O 3 , MgO, MnO, S.
The oxides of recyclable metals Zn, Pb, Ag, Ge, are recovered in the dusts collected in the fume treatment line filter.
Example 4
Mass Balance
On the basis of the experimental studies described in Examples 1, 2 and 3, the mass balance was calculated for the complete treatment method for a weakly acidic leaching residue.
TABLE 1
Mass balance of the desulfurisation/reduction/smelting method
Mass
Element [mass %]
[g]
Fe
Zn
Pb
Cu
C
S
Ag
In
Ge
Gangue
Other
Materials
input
into furnace
Dry weakly
6,000
28.2
22.6
4.9
0.8
0.5
5.6
0.045
0.004
0.0075
18.5
18.8
acidic
leaching
residue
Coal
2,000
55.0
0.7
4.5
39.8
Materials
input
into smelting
furnace
Desulfurised
5,106
32.5
26.0
5.6
0.9
8.9
0.6
0.052
0.005
0.009
23.1
2.2
and pre-
reduced
residue
CaO
900
100.0
Materials
output
from smelting
furnace
Melt
1,648
93.5
<0.01
<0.01
2.49
4.0
0.05
0.016
<0.001
0.001
<0.1
<0.1
Slag
2,183
4.0
<0.5
<0.3
<0.1
<0.5
1.3
93.3
ZnO
2,503
2.7
53.6
11.5
0.2
<0.5
12.8
0.1
0.0095
0.017
2.5
16.1
concentrate
The recovery rate of Ag is greater than 90%; that for Zn, Pb, In and Ge is greater than 95%. | The present invention describes a method for treating residues comprising zinc ferrites and non-ferrous metals selected from among the group made up of lead (Pb), silver (Ag), indium (In), germanium (Ge) and gallium (Ga) or mixtures thereof in the form of oxides and sulfates, comprising the following steps:
roasting of the residues in an oxidizing medium at elevated temperature in order to obtain a desulfurized residue, carburizing reduction/smelting of the desulfurized residue in a reducing medium, liquid phase extraction of carburized melt and slag, vapor phase extraction of the non-ferrous metals, followed by oxidation and recovery thereof in solid form. | 8 |
BACKGROUND OF THE INVENTION
The invention disclosed herein pertains generally to load binders, and more particularly to a lever-type load binder having improved safety features.
Load binders are used in a variety of situations to tension a chain or a wire, and are commonly used to secure large heavy loads, such as logs, to flatbed trucks.
Load binders known in the prior art are illustrated, for example, in U.S. Pat. No. 1,518,769 to Brunk. In the Brunk device ends of each of a pair of load engaging draw bars are pivotably connected at different points along a handle member. The device is tensioned by pivoting of the handle member. During the tensioning the handle acts as a lever to provide a mechanical advantage to draw the ends of the binder together. The tension is sustained by setting the device at a dead center. The device is released by rotating the lever in the opposite direction past dead center.
Various other types of load binders are disclosed in the following patents: U.S. Pat. No. 3,826,469 issued to Ratcliff et al; U.S. Pat. No. 3,842,426 issued to Ratcliff et al; U.S. Pat. No. 4,122,587 issued to Weiss et al; U.S. Pat. No. 398,714 issued to Farr; U.S. Pat. No. 1,972,346 issued to Julins; and U.S. Pat. No. 2,539,997 issued to Graves.
A serious problem encountered by users of conventional load binders is "flyback." That is, upon grasping the handle and initially pivoting the lever of a conventional load binder to release the tension, the user of the load binder may be subjected to the danger of being struck by the handle. This danger may arise because the handle is suddenly subjected to the tension force in the chain during release, and, if this tension force is large enough, it will cause the handle to pivot with considerable momentum. Since a user may pull the handle of the load binder toward himself in order to release the load binder, the user may thereby expose himself to the danger of "flyback," i.e., to the danger of being struck by the handle and/or lever pivoting toward the user in an uncontrolled manner.
The danger of flyback is exacerbated in the case of those users who mount lengths of pipe, called "cheaters," on the handles of conventional load binders. By using a cheater, a user effectively increases the length of the lever arm of the load binder, allowing the user to exert a larger tensioning force than he would otherwise be able to exert. As a consequence, however, the handle of the load binder will be subjected to a larger force when the load binder is initially released, resulting in the possibility that the handle and cheater will be propelled toward the user with even greater momentum.
Yet another problem associated with conventional load binders is the difficulty involved in releasing the load binder when the load binder has been used to subject a chain or wire to a relatively large tension. That is, because there is a relatively large tension force in the chain or wire, a user must exert a relatively large force on the handle of the load binder in order to release the load binder.
Accordingly, it is an object of the present invention to provide a simply and inexpensively constructed load binder which can be operated with an advanced degree of safety for the user.
It is another object of the present invention to provide a lever-type load binder which minimizes the danger of flyback.
It is yet another object of the present invention to provide a load binder wherein the actuating handle is used in conjunction with a separate lever element to tension the load binder and wherein the actuating handle may be selectively disengaged from the lever element and employed to trigger the release of the load binder.
It is still another object of the present invention is to provide a lever-type load binder which may be used to subject a chain or wire to a relatively large tension force, may be safely and securely locked in a tensioned configurations and may be released with relatively little effort.
These and other objects and features of the invention will become apparent from the claims and from the following description when read in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
Preferred embodiments of the present invention are described with reference to the accompanying drawings wherein like members bear like reference numerals, and wherein:
FIG. 1 is a pictorial view of a first preferred embodiment of a lever-type load binder, according to the present invention;
FIG. 2 is a front view of the embodiment of FIG. 1 showing the relative positions of the components of the first embodiment after a tensioning stroke;
FIG. 3 is a pictorial view of a portion of the embodiment shown in FIG. 1, depicting shoulders at the lower ends of the arms of the actuating means and the tabs connected to the lower ends of the arms of the lever member;
FIG. 4 is a cross-sectional view of the embodiment shown in FIG. 1, taken on the plane 4--4 of FIG. 1, showing the relative positions of the components of the first preferred embodiment of the load binder, according to the present invention, at or near the end of a release stroke;
FIG. 5 is a view similar to FIG. 4, showing the relative positions of the components of the first preferred embodiment at the beginning of a tensioning stroke;
FIG. 6 is a view similar to FIG. 4, showing the relative positions of the components of the first preferred embodiment at the end of a tensioning stroke;
FIG. 7 is a view similar to FIG. 4, showing the relative positions of the components of the first preferred embodiment at the beginning of a release stroke;
FIG. 8 is a view similar to FIG. 4, showing the relative positions of the components of the first preferred embodiment at the midpoint of a release stroke; and
FIG. 9 is a pictorial view of a second preferred embodiment of a lever-type load binder, according to the present invention.
DETAILED DESCRIPTION
A lever-type load binder, according to the present invention, includes a lever member, a draw bar and a clevis, the draw bar and clevis being pivotably attached to opposite ends of the lever member. The draw bar and clevis may each be equipped with hooks to couple the binder to a load. The load binder also includes a pivotable handle for engaging and pivoting the lever member with respect to the clevis and draw bar. The handle engages and pivots the lever member during a tensioning stroke, and triggers the release of the load binder during a return stroke of the handle after the handle has been pivoted out of the path of rotation of the lever member, thus preventing flyback of the handle on release of the load binder.
As used herein the terms "load" or "loads" are intended to refer to a force or forces external to the binder which resist the tensioning of the binder.
Referring first to FIG. 1, an embodiment of a load binder of the present invention is denoted generally by the numeral 10. The binder includes a lever or connecting member 42, having a U-shaped clevis 20 pivotably attached at one end thereof, and a draw bar 80 pivotably attached near the other end thereof. In other words, the clevis 20 and the draw bar 80 are pivotably attached to the lever or connecting member 42 at points displaced from one another. It will be readily apparent from the Figures that relative pivoting of the lever member 42 with respect to the clevis 20 and draw bar 80 will vary the distance between grab hook 40 and grab hook 96. Tensioning of the load binder is effected by rotations of the handle or actuating member 62. When fully tensioned, the load binder may assume the configuration shown in FIG. 2. When released, the load binder may assume the configuration shown in FIG. 4.
With continued reference to FIG. 1, the structure of the illustrated embodiment is described in greater detail. The clevis 20 includes substantially rectangular, parallel arms 22 and 24, as well as a substantially rectangular member 26 arranged transversely with respect to the arms 22 and 24, and connected to one end of each of the arms 22 and 24. The member 26 defines an upper end of the clevis 20. A substantially cylindrical member 28, of relatively small diameter, is arranged transversely with respect to the arms 22 and 24, and is also connected to the arms 22 and 24. The cylindrical member 28 is connected to the arms 22 and 24 at a distance from the top end of the clevis approximately equal to half the length of the arms 22, 24. The cylindrical member 28 defines a stop for the lever member normally beyond the dead center of the lever-type load binder. Dead center occurs when the load binder is tensioned and the forces applied to the load to the clevis 20 and draw bar 80 are colinear and perpendicular to the axes of pivoting of the lever member.
Connected to the top end of the clevis 20 is a ball socket 30. The ball socket 30 receives the ball-shaped end 36 of a link 34. The link 34 is connected by a link 38 to a grab hook 40. The grab hook 40 permits a user to connect one end of the lever-type load binder to a load. The ball and socket joint permits the grab hook to swivel in response to changes in the directon of forces applied to the load binder.
The generally U-shaped lever member 42 is pivotably connected to an end of the clevis 20. The U-shaped lever member 42 includes a top member 44 having a substantially rectangular engagement surface 46 which faces away from the clevis 20. Two substantially rectangular, parallel legs 48 and 50 are connected to the top member 44. Lower ends 52 and 54 of the legs are disc-shaped. The U-shaped lever member 42 is dimensioned so that it may fit between the arms of the clevis 20. The lever member 42 is pivotably connected to the lower end of the clevis 20 by pivot pins 60 and 61. The pivot pin 60 penetrates through an opening in the lower end of the arm 24 as well as through an opening in the disc-shaped end 52 of the lever member. Likewise, the pivot pin 61 penetrates through an opening in the lower end of the arm 22, as well as through an opening in the disc-shaped end 54. The pivot pins 60 and 61 define a pivot axis about which the lever member 42 may pivot with respect to the clevis 20. The length of the lever member 42 is such that when the lever member is pivoted downwardly toward the clevis 20, the top end 44 will come into contact with the cylindrical stop member 28. Advantageously, the lever member 42 may pivot downwardly toward the clevis 20 at least as far as the dead center of the load binder.
The generally Y-shaped actuating member 62, for engaging and pivoting the lever member 42 with respect to the clevis 20, is also pivotably connected to the lower end of the clevis 20. The Y-shaped actuating member includes a handle 64, as well as two substantially rectangular, parallel arms 66 and 68 which depend from the handle 64. The dimensions of the Y-shaped actuating member 62 are such that the arms 66 and 68 fit between the legs 48 and 50 of the U-shaped lever member 42. The lower ends of each of the arms 66 and 68 of the actuating member 62 have openings, each of which openings receives one of the pivot pins 60, 61. Thus, the Y-shaped actuating member 62 is pivotable with respect to both the lever member 42 and the clevis 20. The length of each of the arms 66 and 68 of the actuating member 62 is greater than the length of the lever member 42. Thus, when the actuating member 62 is pivoted in a clockwise direction (as seen in FIG. 1) with respect to the clevis, the arms 66 and 68 will come into contact with the rectangular engagement surface 46 at the top of the U-shaped lever member 42. It will be readily understood that further pivoting of the actuating member in the clockwise direction will serve to rotate the lever member with respect to the clevis.
The substantially rectangular draw bar 80 is arranged between the arms 66 and 68 of the actuating member 62, as well as between the legs 48 and 50 of the lever member 42. The draw bar 80 is pivotably connected to the lever member 42 at a point adjacent the top 44 of the lever member 42. This pivotable connection is effectuated by pivot pin 82 which projects through openings in the legs 48 and 50 of the lever member 42, as well as through an opening in a lower end of the draw bar 80. A hollow, substantially triangular member 84 is connected to an upper end of the draw bar 80. A ball socket 86, similar to ball socket 30, is connected to the triangular member 84. The ball socket 86 receives a ball-shaped end (not shown) of a link 90. The link 90 is connected by a link 94 to the second grab hook 96. The second grab hook 96 allows a user to connect the draw bar 80 to a load.
With reference to FIG. 3, the lower ends of each of the arms 66 and 68 of the actuating member 62, which lower ends are mounted on the pivot pins 60 and 61, are generally circular in shape. The juncture between the relatively straight portion of the arm 66 and the circular lower end of the arm 66, defines a shoulder 70. Similarly, the juncture between the relatively straight portion of the arm 68 and the lower circular portion of the arm 68 defines a shoulder 72. The diameters of the lower circular portions of the arms 66 and 68 are less than the diameters of the disc-shaped ends 52 and 54 of the legs 48 and 50 of the lever member 42. A tab 56 is connected to an inner surface of the circular member 52, adjacent a peripheral edge surface of the lower circular end of the arm 66. Similarly, a tab 58 is connected to an inner surface of the circular member 54, adjacent a peripheral edge surface of the lower circular end of the arm 68. A counter-clockwise rotation of the arm 66 and 68 of the actuating member 62 results in the shoulders 70 and 72 of the arms 66 and 68 engaging the tabs 56 and 58 connected to the disc-shaped ends 52 and 54 of the lever member 42.
The tensioning of the first embodiment of the lever-type load binder, according to the present invention, will now be described with reference to FIGS. 1, 5 and 6. The grab hooks 40 and 96 may be connected, for example, to opposite ends of a chain to be tensioned. A user may grasp the handle 64 of the actuating member 62 and pivot it in a clockwise direction (as seen in FIGS. 1, 5 and 6) until the arms 66 and 68 of the actuating member 62 come into contact with the engagement surface 46 of the lever member 42 as shown in FIG. 5. The continued clockwise pivoting of the actuating member 62 results in the lever member 42 also being pivoted in the clockwise direction. The clockwise pivoting motion of the lever 42 may continue until the lever 42 comes into contact with, and is stopped by, the cylindrical stop member 28 connected to the arms 22 and 24 of the U-shaped clevis 20, as shown in FIG. 6. As is apparent from the drawings, the path of clockwise tensioning rotation of the lever member is arcuate and substantially perpendicular to the pivoting axis of the lever member. As the lever member 42 is pivoted in the clockwise direction, the draw bar, 80 which is pivotably connected to the lever 42, is drawn toward the clevis 20. Thus, the opposite ends of the chain connected to the grab hooks 40 and 96 are also drawn toward one another, and the chain is thereby tensioned. The relative positions of the various components of the first embodiment of the lever-type load binder, according to the present invention, at the end of a tensioning stroke are shown in FIG. 2. In particular, it is to be noted that the actuating member 62 is in flush contact with the clevis 20 at the end of a tensioning stroke.
The steps involved in releasing the tension imposed on the chain by the first embodiment of the lever type load binder, according to the present invention, will not be described with reference to FIGS. 1, 7 and 8. To release the load binder, the user once again grasps the handle 64 of the actuating member 62 and pivots the handle in a counter-clockwise direction (as seen in FIGS. 1, 7 and 8). The counter-clockwise pivoting motion of the actuating member 62 is continued until the shoulders 70 and 72 of the arms 66 and 68 of the actuating member 62 engage the tabs 56 and 58 connected to the disc-shaped ends 52 and 54 of the lever member 42 as shown in FIG. 7. Once the shoulders 70 and 72 have engaged the tabs 56 and 58, the user continues to pivot the actuating member 62 in the counter-clockwise direction in order to urge the tabs 56 and 58, and thus the lever member 42, to pivot in the counter-clockwise direction. Once the lever member has been pivoted through a relatively small angular distance 98 from the stop member 28 and past dead center, the tension in the chain may be sufficient to urge the lever member 42 to continue to rotate in the counter-clockwise direction in order to relieve the tension in the chain as shown in FIG. 8 as is apparent from the drawings, the path of counter-clockwise release rotation of the lever member is arcuate and substantially perpendicular to the pivoting axis of the lever member. It is to be noted that as the lever member 42 pivots in the counter-clockwise direction the draw bar 80, which is pivotably connected to the lever member 42, moves away from the clevis 20.
The relative positions of the components of the first embodiment of the lever-type load binder, according to the present invention, at or near the end of a release stroke, are shown in FIG. 4. In particular, it is to be noted that the lever member has pivoted in the counter-clockwise direction through more than ninety-degrees, and that the tabs 56 and 58 are now separated from the shoulders 70 and 72 by a substantial angular distance.
An advantage of the present invention is that to initiate a release stroke, the actuating member 62 must be pivoted by a user in the counter-clockwise direction through a substantial angular distance before the shoulders 70 and 72 even come into contact with the tabs 56 and 58. Thus, the actuating member 62 is pivoted out of the path of the lever member 42 before the lever member 42 even begins to undergo the tension releasing, counter-clockwise pivoting motion. Because the actuating member 62 is separate and distinct from the lever member 42, and because the actuating member 62 is pivoted well out of the path of the lever member 42 at the beginning of a release stroke, the dangers of flyback associated with conventional load binders are avoided.
Once the shoulders 70 and 72 have been pivoted into an engagement with the tabs 56 and 58, only a relatively small force need be applied by a user during a release stroke in order to pivot the lever member 42 through the dead center of the load binder. Once the lever member 42 has been moved off the dead center of the load binder, the tension in a tensioned chain, for example, is sufficient to urge the lever member 42 to continue to pivot in the counter-clockwise direction in order to completely relieve the tension in the chain.
A second preferred embodiment 110 of the lever-type load binder, according to the present invention, is illustrated in FIG. 9. The load binder 110, like the load binder of FIGS. 1-8, also includes a generally U-shaped clevis 120. The clevis 120 includes substantially rectangular, parallel arms 122 and 124. A curved member 126, which is arranged transversely with respect to the arms 122 and 124, and which is connected to one end of the arms 122 and 124, defines a top end of the clevis 120. A cross-bar 128, which is arranged transversely with respect to the arms 122 and 124, and which is connected to the arms 122 and 124 at a point mid-way along the length of the arms 122 and 124, defines a stop for the second embodiment of the lever-type load binder. The cross-bar 128 prevents a lever member 142 from moving far past dead center.
A ball-socket 130, is connected to the top end of the clevis 120. The ball-socket 130 receives the ball-shaped end 136 of a link 134. The link 134 is connected by a chain link 138 to a grab hook (not shown). The grab hook permits a user to connect the clevis 120 to a load.
A generally Y-shaped handle member 162 is pivotably connected to a lower end of the clevis 120. The handle member 162 includes a handle 164, as well as two substantially rectangular, parallel arms 166 and 168 connected to the handle 164. The arms 166 and 168 of the handle member 162 are dimensioned to fit between the arms 122 and 124 of the clevis 120. The lower ends of the arms 166 and 168 of the handle member 162 are pivotably connected to the lower ends of the arms 122 and 124 of the clevis 120 by pivot pins 160 and 161. The pivot pin 160 projects through an opening in the lower end of the arm 124 as well as through an opening in the lower end of the arm 166. The pivot pin 161 projects through an opening in the lower end of the arm 122 as well as through an opening in the lower end of the arm 168. The pivot pins 160 and 161 define a pivot axis about which the handle member 162 may be pivoted with respect to the clevis 120.
The generally U-shaped lever member 142 is also pivotably connected to the lower ends of the arms 122 and 124 of the clevis 120. The lever member 142 includes a curved top member 144, to which is connected two substantially rectangular, parallel legs 148 and 150. The lower ends of each of the legs 148 and 150 are disc-shaped end portions 152, 154, respectively. The lever member 142 is dimensioned so that the legs 148 and 150 may be inserted between the arms 166 and 168 of the Y-shaped handle member 162. The lever member 142 is pivotably connected to the clevis 120 by the pivot pins 160 and 161. The pivot pins 160 and 161 project, respectively, through openings in the arms 124 and 120 the legs 166 and 168 and centers of the disc-shaped ends 152, and 154. Thus, the pivot pins 160 and 161 define a pivot axis about which the lever member 142 may pivot with respect to the clevis 120. It is to be noted that the length of the arms 166 and 168 of the handle member 162 is greater than the length of the legs 148 and 150 of the lever member 142.
A substantially rectangular draw bar 180 is arranged between the arms 166 and 168 of the handle member 162, as well as between the legs 148 and 150 of the lever member 142. A first end of the draw bar 180 is pivotably connected to the legs 148 and 150 of the lever member 142 by a pivot pin 182. The pivot pin 182 passes through apertures in the legs 148 and 150 as well as through an aperture in the draw bar 180. Connected to a second end of the draw bar 180 is a hollow, substantially triangular member 184. A ball-socket 186 is connected to the top of the triangular member 184. A ball-shaped end of a link 190 is received in the ball-socket 186. The link 190 is connected by a chain link 194 to a grab hook (not shown). The grab hook permits a user to connect the draw bar to a load.
A tensioning pin 196 is connected to, and projects outwardly from, an upper end of the leg 148 of the lever member 142. Similarly, a tensioning pin 198 is connected to, and projects outwardly from, the leg 150 of the lever member 142. The tensioning pins 196 and 198 may be engaged by edge surfaces of the arms 166 and 168 of the handle member 162, when the handle member 162 is pivoted in the clockwise direction (as seen in FIG. 9).
The lower ends of the arms 166 and 168, mounted on the pivot pins 160 and 161, are generally semi-circular in shape. The diameters of the semi-circular portions of the arms 166 and 168 are smaller than the diameters of the disc-shaped ends 152 and 154 of the lever member 142. A release pin 200 is connected to, and projects outwardly from, an outer surface of the disc-shaped end 152. The release pin 200 is arranged adjacent to a peripheral edge surface of the semi-circular portion of the arm 166 of the handle member 162. A release pin 202 (not shown) is also similarly attached to the disc-shaped end 154. Thus, when the handle member 162 is pivoted in a counter-clockwise direction the lower edge surfaces of the arms 166 and 168 may engage the release pins 200 and 202.
Assuming that the grab hooks have been connected to, for example, the ends of a chain to be tensioned, the steps involved in tensioning the chain with the second embodiment 110 of the present invention are as follows. A user grasps the handle 164 of the handle member 162 and pivots the handle member 162 (in a clockwise direction in FIG. 9) until the upper edge surfaces of the arms 166 and 168 engage the tensioning pins 196 and 198. The continued clockwise motion of the handle member 162 results in the lever member 142 also being pivoted in the clockwise direction. The lever member 142 will continue to pivot in the clockwise direction past dead center until the lever member 142 comes into contact with, and is stopped by, the cross bar 128. As the lever member pivots in the clockwise direction, the draw bar 180 will be drawn toward the clevis 120, thereby tensioning the chain. In addition, as the lever member 142 is pivoted in the clockwise direction the release pins 200 and 202 will also pivot in the clockwise direction to a position where they may be engaged by the handle member 162 during a release stroke.
In order to release the tension on the chain, the user grasps the handle 164 and pivots the handle member 162 in a counter clockwise direction until the lower edge surfaces of the arms 166 and 168 engage the release pins 200 and 202. The continued rotation of the handle member 162 in the counter clockwise direction will result in the release pins 200 and 202, and thus the lever member 142, also being pivoted in the counter clockwise direction. Once the lever member 142 is moved counter-clockwise past its dead center, the tension in the chain will be sufficient to urge the lever member 142 to continue to pivot in the counter clockwise direction in order to completely relieve the tension in the chain.
An advantage of the second embodiment of the present invention, like the first embodiment, is that at the initiation of a release stroke the handle member 162 is pivoted out of the path of the lever member 142 even before the lever member 142 begins to pivot counter-clockwise away from dead center. Thus, the second embodiment avoids the problem of flyback.
The principles, preferred embodiments and modes of operation of the present invention have been described in the foregoing specification. The invention which is intended to be protected herein, however, is not to be construed as limited to the particular forms disclosed, since these are to be regarded as illustrative rather than restrictive. Variations and changes may be made by those skilled in the art without departing from the spirit of the present invention. | A lever-type load binder is disclosed in which the necessary force to draw the ends of the binder together is provided by a pivoting lever element. The binder employs a handle for tensioning and releasing the binder. The handle and lever element are constructed so that the handle positively engages the lever element to pivot the lever element on the tensioning stroke. However, the handle is employed merely to trigger the release stroke by rotating the lever element through dead center while the handle is out of the path of travel of the lever element. Because of this feature, the user is not endangered by a "flyback" of the handle when the binder is released. | 5 |
CROSS REFERENCE TO ISSUED PATENT
Reference is made to applicant's prior U.S. Pat. No. 2,931,456, granted Apr. 5, 1960. In such prior patent, an electric motor provides the power for moving the stairway between operative and inoperative positions, and chain and cable means are employed for transmitting movement from the motor to the stairway. The same guide rollers and rails are employed for guiding the stairway between operative and inoperative positions, as referred to above.
SUMMARY OF THE INVENTION
The invention comprises a stairway formed of spaced parallel side runners and steps connected therebetween, and the stairway moves within a framed opening in the ceiling. The framing of the opening carries a transverse roller which supports the stair runners in the movement of the stairway between operative and inoperative positions. A pair of concavely grooved rollers are rotatably supported by a pivoted plate to rock therewith to assume different positions in engagement with a rail connected at its upper end to each of the runners and at its lower end to such runners so that the movement of the stairway between its two positions will be guided. Hydraulic power means is mounted beneath the stairway. This power means comprises two side-by-side hydraulic cylinders, each having a piston provided with a piston rod, and the piston rods of the two hydraulic cylinders project in opposite directions. One piston rod has its free end pivotally connected to a bearing bracket connected to a cross member of the framing of the opening, while the free end of the other piston rod is pivotally connected to the stairway adjacent its lower end.
An electric motor drives a pump to supply hydraulic pressure to the cylinders and fluid is returned from the cylinders to a reservoir connected to the intake side of the pump. The two cylinders have opposite ends thereof connected by suitable piping so that when fluid is supplied by the pump to one end of one cylinder, such fluid automatically flows to the opposite end of the other cylinder. When one piston rod is moved from its cylinder, therefore, the other piston rod is similarly moved in the opposite direction, thus exerting pushing forces between the frame and the bottom of the stairway to move the stairway to its angular operative position. When fluid is admitted to the other ends of the cylinders, the pistons are oppositely retracted to exert a pulling force on the lower end of the stairway to move it to its upper inoperative position. The cylinders are fixed with respect to each other but are not fixed to the stairway, and the flow of hydraulic fluid to and from the cylinders is controlled by electrically operated valves.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevation of the stairway shown in solid lines in its operative position and in its relationship to the framed ceiling opening, the transverse members of which are shown in section;
FIG. 2 is a plan view of the stairway shown in its upper horizontal inoperative position and showing the ceiling opening;
FIG. 3 is a fragmentary enlarged elevation of a portion of one of the guide rails and the associated rollers which guide the rails to guide the movement of the stairway;
FIG. 4 is a fragmentary detailed sectional view on line 4--4 of FIG. 3;
FIG. 5 is a fragmentary detailed sectional view on line 5--5 of FIG. 1; and
FIG. 6 is a diagrammatic view of the wiring and hydraulic connections for the structure.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIGS. 1 and 2, numeral 10 designates the stairway as a whole comprising spaced parallel side runners 11 connected by steps 12. The stairway is provided at opposite sides with guide rails 13, which also function as handrails. Each guide rail is provided with a straight intermediate section 14 curved at its upper end on a substantial radius as at 15 and at its lower end, a curved section 16 is provided. The extremities of the curve rail sections are fixed to the runners 11.
The ceiling structure 18 of the room is provided with an opening 20 through which the stairway is adapted to move and this opening is formed by a frame structure including longitudinal members 21 and transverse members 22. A bracket 24 is secured against each frame member 21 and is provided with a pin 26 pivotally supporting a plate 28, carrying a pair of concavely grooved rollers 30 between which the associated guide rail 13 is adapted to move. The pivoting of the plates 28 allows them to adjust themselves to the angularity of the rails 13 as the stairway moves between operative and inoperative positions. This will be apparent from FIG. 1 in which an intermediate position of the stairway 10 is shown in dotted lines and an upper inoperative position is shown in broken lines.
Referring to FIG. 2, a plate 32 is fixed to one of the transverse members 22 and carries upwardly and inwardly projecting end members 34 rotatably supporting a roller 36, each end portion of which is flanged as at 38. The roller 36 supports the stairway in its movement between its two positions and the stairway is properly guided by the flange 38.
Beneath the stairway is arranged a pair of hydraulic cylinders 40 and 42 (FIGS. 2 and 6) fixed together by suitable clamps 44. These cylinders are respectively provided with pistons 46 and 48, and these pistons, in turn, are respectively provided with piston rods 50 and 52. The piston rod 50 projects through a bearing 54 in one end of the associated cylinder 40 while the piston rod 52 projects through the similar bearing 56 carried by one end of its associated cylinder 42.
The plate 32 carries ears 58 pivotally connected as at 60 to the extremity of the piston rod 50. A plate 62 (FIGS. 1 and 2) is connected between the stair runners 11 and is provided with depending ears 64 pivotally connected as at 66 to the extremity of the piston rod 52. Referring to the diagrammatic drawing in FIG. 6, it will be seen that a pipe 68 connects the ends of the cylinders 40 and 42 opposite the pivotal connections 60 and 66. A similar pipe 70 connects the other ends of the hydraulic cylinders. Thus it will be seen that if fluid is admitted to the left hand end of cylinder 42 in FIG. 2, it also will be admitted to the right hand end of cylinder 40. This will cause the pistons 46 and 48 to move respectively to the left and right to exert a force on the stairway to cause it to move to the right in FIG. 2. Similarly, if fluid is admitted to the left hand end of cylinder 40, the fluid will be admitted to the right hand end of cylinder 42 to exert a pulling force on the right hand end of the stairway in FIGS. 1 and 2 to move the stairway to its inoperative position.
A door for the ceiling opening 20 is provided and indicated at 72 (FIG. 1). This door is pivoted as at 74 to the adjacent plate 32. Adjacent opposite sides of its free end, the door is provided with upstanding arms 76 (FIGS. 1 and 5), each carrying at its upper end a roller 78 engaging an elongated angle plate 80 fixed to the associated runner 11. The rollers 78 travel relatively upwardly along the track 80 as the stair is lowered and relatively downwardly as the stair is moved to inoperative position to close the opening 20.
In FIG. 6, there is illustrated in simplified form, a wiring and piping diagram for the stairway. A pair of inlet valves 82 and 84 control the admission of fluid to the cylinders 40 and 42 and solenoids 86 and 88, respectively, control these valves. Relief valves 90 and 92 control the flow of fluid from the cylinders 40 and 42 back to a reservoir 94 having a pipe 96 leading to the intake side of pump 98 driven by a motor 100. The valves 90 and 92 are operated by solenoids 102 and 104, respectively.
The pump 98 has its outlet connected by a pipe 106 to the inlet valve 82 and such valve has a pipe 108 leading to the left hand end of the cylinder 42 as viewed in FIG. 6. The pipe 106 is also connected by a pipe 110 to the inlet valve 84 from which a pipe 112 leads to the left hand end of the cylinder 40. The valve 92, which is one of the fluid pressure relief valves, is piped as at 114 to the pipe 112. The second pressure relief valve 90 is connected by a pipe 116 to the pipe 108 and is also connected by a pipe 118 to the reservoir 94. The outlet of the valve 92 is connected as at 120 to the pipe 118.
A two-way switch 122 controls the motor 100 and the various solenoids described. This switch comprises an arm 124 connected to a current source as at 126 and movable selectively into engagement with contacts 128 and 130. The contact 128 is connected by a wire 132 to a limit switch 134 which controls upward movement of the stairway from operative to inoperative position. The wire 132 is connected as at 136 to the motor 100 and this motor is connected as at 138 to a wire 140 connected to the other side of the source. The second terminal of the switch 134 is connected to a wire 142, which wire is connected as at 144 and 146 to the respective solenoids 88 and 102.
The contact 130 is connected as at 148 to a second limit switch 150 which controls downward movement of the stairway. The other terminal of the switch 150 is connected by a wire 152 to the solenoid 86 and the wire 152 has a lead 154 connected to the solenoid 104. The other terminals of all of the solenoids are connected to the wire 140, as shown.
OPERATION
Assuming that the stairway is in the horizontal normal position shown in FIG. 2 and in broken lines in FIG. 1, and it is desired to lower the stairway, the two-way switch 122 will be operated by moving the switch arm 124 downwardly into engagement with the contact 130. Current will flow through switch 150 to solenoids 86 and 104 to open the valves 82 and 92. The pump 98 will now supply fluid through pipe 108 and valve 82 and through pipe 108 to the left-hand end of the cylinder 42 as viewed in FIG. 6. Fluid thus supplied to the cylinder 42 will flow through pipe 68 to the right-hand end of the cylinder 40 thus moving the piston 48 of cylinder 42 to the right and piston 46 of motor 40 to the left. This obviously exerts a pushing force on the plate 62 and thus to the right-hand end of the stairway as viewed in FIG. 1. The stairway thus will be moved to the right and its movement will be guided by engagement of the rails 13 with the rollers 30. The angularity of the rails will change during such movement and such change in angularity is permitted by the rocking movement of the plate 28. When the stair reaches its lower position, the circuit will be broken at the switch 134 and the motor stopped.
It will be apparent that the movement of the hydraulic pistons as described will displace fluid from the right-hand end of the cylinder 42 and from the left-hand end of the cylinder 40. Fluid from the right-hand end of the cylinder 42 will flow through pipe 70 into the left-hand end of cylinder 40, from which the fluid will be displaced through pipes 112 and 114. The relief valve 92 being open, the fluid will flow back to the reservoir through pipes 120 and 118. During this operation, it will be obvious that both valves 84 and 90 will be closed.
When it is desired to return the stairway to its upper inoperative position, the switch arm 124 will be moved into engagement with the contact 128 to energize the motor, and through limit switch 134, and wires 142, 144, and 146 to energize the solenoids 88 and 102. The solenoids 86 and 104 will remain deenergized. Pumped fluid will then pass through pipes 108 and 110 and through valve 84 and pipe 112 to the left-hand end of the cylinder 40, which is connected by pipe 70 to the right-hand end of the cylinder 42. Both of the hydraulic pistons and their rods will now be retracted to exert an endwise pull on the lower end of the stairway, causing it to move upwardly while its movement is guided by engagement of the rails 13 with the rollers 30.
The retractile movement of the hydraulic pistons will displace fluid from the right-hand end of the cylinder 40 through pipe 68 to the left-hand end of the cylinder 42, which will now be connected to the reservoir through pipes 108 and 116, valve 90, and pipe 118. This movement continues until the stairway reaches normal inoperative position, whereupon operation of the limit switch 134 will break the circuits through the motor 100 and solenoids 88 and 102.
The wiring diagram has been made as simple as possible merely to give an understanding of the operation of the system as a whole. The limit switches form no part of the present invention and accordingly have not been illustrated in detail.
It will be apparent that the great change in the distance between the pivot points 60 and 66 in the movement of the stairway between its two positions is such that a single hydraulic cylinder cannot be used. Hence the use of two hydraulic cylinders with the interconnection thereof by the pipes 68 and 70. Thus the sum of the movements of the hydraulic pistons and piston rods provides the total movement necessary for moving the stairway between operative and inoperative positions.
The present construction is advantageious over the structure disclosed in my prior patent identified above. In the first place, the present construction eliminates the cables, pulleys, etc. of the prior construction, and accordingly is easier and more economical to manufacture. Many stairways constructed in accordance with the prior patent have been sold, and while there has never been a known failure of any of the cables, there is a remote possibility that this may occur, particularly after many years of use of the stairways. The present construction eliminates even a remote possibility of the failure of any of the parts due to the simple mechanical construction and the incompressibility of the hydraulic fluid. Accordingly, the present construction should last for many trouble-free years. | A unitary stairway (as distinguished from a sectional folding stairway) is adapted to assume an inclined operative position and an upper horizontal inoperative position above the ceiling of the room. Hydraulic means imparts longitudinal forces to the stairway to move it upwardly or downwardly, and rails carried by the stairway are engageable in guide rollers to guide the stairway between operative and inoperative positions. A wall switch is operable to energize a motor for driving a pump to generate power in the hydraulic means. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The subject invention relates to a circuit for detecting and synchronizing a ghost cancellation reference signal contained in a television signal.
2. Description of the Related Art
U.S. Pat. Nos. 5,047,859 and 5,121,211 both to Koo disclose a signal which, when transmitted with a standard television signal, enables a corresponding circuit to correct said signal thereby eliminating "ghost", i.e., errors in the signal arising from, for example, reflections from buildings, terrain, etc. For a ghost canceler to be effective, the ghost cancellation reference (GCR) signal must be detected and stored digitally to be processed. The methods for the detection of this signal involve a determination of a particular line of the video signal from analog or digital video synchronization signal processors and then comparing this detected signal to a stored reference GCR signal. These processors are designed to accommodate standard NTSC signals or standard video signals with low S/N characteristics, but not ghosted signals. Ghosting causes the video synchronization levels to change dynamically line-to-line. Simple level-slicing methods are insufficient under ghosted signal conditions. This means that the horizontal synchronization pulses cannot be reliably counted with respect to the vertical interval, thereby introducing errors in determining the location of the GCR signal to be detected. Other methods involving sync. prediction use either differentiation or integration, or a combination of both, as feedback to the prediction algorithm. This means that the sync. processor can be stabilized, but the statistical error over a few lines can allow the predictor to be off by one or more lines resulting in an erroneous detection of the GCR signal.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a circuit for reliably detecting and synchronizing to the GCR signal.
This object is achieved in a circuit for detecting and synchronizing a ghost cancellation reference (GCR) signal in a television video signal, comprising means for receiving at least one field of an input video signal; means for finding a maximum correlation peak value in a field of said input video signal; means for scaling said maximum correlation peak value to a lower predetermined value for detection for forming a scaled peak value; means for synchronizing a next field of said video signal using said scaled peak value; and means for predicting a future position of the GCR signal.
The Koo GCR signal itself is a very high energy signal. If it is correlated with the stored reference GCR signal, the correlation peak is very definitive. The correlation is immune to low S/N ratios, dc-offsets generated by ghosting, and other video corruptions, such as VCR playbacks. The subject invention uses the ghost canceling filter as a match filter during predicted GCR signal times.
BRIEF DESCRIPTION OF THE DRAWINGS
With the above and additional objects and advantages in mind as will hereinafter appear, the invention will be described with reference to the accompanying drawings, in which:
FIG. 1 shows a block diagram of the GCR detection and synchronization circuit of the subject invention;
FIG. 2 shows a block diagram of the GCR synchronization circuit portion of the circuit of FIG. 1;
FIG. 3 shows a flowchart diagraming the operation of the circuit of FIG. 2;
FIG. 4 shows a flowchart diagraming a windowing operation when the PDFA is used as a real-time cross correlator;
FIG. 5 shows a flowchart diagraming the windowing operation when the multiply/accumulate based correlator is used to calculate the cross correlation;
FIG. 6 shows a block diagram of the multiply/accumulate based correlator;
FIG. 7 shows a flowchart diagraming the capturing of the zero padded GCR signal; and
FIG. 8 shows a flowchart diagraming the correlation of WinSize point of cross correlation.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows a block diagram of the GCR detection and synchronization circuit of the subject invention. A received video signal containing the GCR signal is digitized in an analog-to-digital (A/D) converter 1. An output of the A/D converter 1 is applied directly to a first input of a bypass multiplexer 2, the output from which is applied to a digital-to-analog (D/A) converter 3, the output therefrom forming the output of the circuit.
The output of the A/D converter 1 is also applied, through a programmable digital filter array (PDFA) 4, to a second input of the bypass multiplexer 2, to a memory 5, and to a multiply/accumulate based (MACB) correlator 6. An output from the MACB correlator 6 and the output from the PDFA 4 are applied to the first and second inputs, respectively, of a multiplexer 7, an output of which, comprising a correlation signal, is applied to a GCR synchronization circuit 8. The GCR synchronization circuit 8, in turn, supplies a correlation selection signal for switching the multiplexer 7.
The circuit also includes a filter configuration control and adaption algorithm circuit 9 for controlling the PDFA 4 and the bypass multiplexer 2. The circuit 9 is connected to receive and write information from/to the memory 5, and receives a correlation mode signal, a GCR window signal, a GCR present signal, and an initialization signal from the GCR synchronization circuit 8. The GCR window signal is also applied to a control input of the MACB correlator 6.
The circuit shown in FIG. 1 is a general architecture for a ghost cancellation system. The major circuit functionality consists of three primary modes of operation:
1. GCR Averaging
2. Channel Adaptation
3. Filter Coefficient Update
During averaging mode, the GCR signal must be accurately located, otherwise, erroneous averaging will occur. The GCR synchronization circuit 8 along with the MACB correlator 6 comprise the inventive approach to locating the GCR signal line accurately. Channel Adaptation and Filter Coefficient Update can be handled purely in software, and the GCR synchronization circuit 8 does not have a direct impact on these circuit functions.
The filter configuration control and adaptation algorithm circuit 9 may be implemented with any general purpose microprocessor (μp). The PDFA 4 must have approximately 500 taps, be user configurable as a single N-tap FIR filter, with user programable coefficients. Three Philips GB-180 filter chips may be used for the PDFA 4.
At power on, the GCR synchronization circuit 8 signals the μP to initialize, which resets the PDFA 4 and places the bypass multiplexer 2 in "BYPASS" mode. After initialization, the GCR synchronization circuit 8 signals the μP to configure the PDFA 4 in the correlation mode and to load the filter coefficients with the time-reversed GCR signal by activating the CorrMode signal line, which, in effect, turns the PDFA 4 into a real-time GCR cross correlator. When a correlation peak is detected by the GCR synchronization circuit 8, the peak value is scaled and stored. The GCR synchronization circuit 8 then measures and stores the time (ΔT) between correlation peaks. The stored ΔT is used to generate a "window" (GCR-Window), which is active for the length of the GCR signal. If a correlation peak is not detected, then the assumption made is that no GCR signal is present. Since de-ghosting is not possible without a received GCR signal, the circuit continuously searches for a correlation peak while the video is bypassed.
Once the correlation peak and ΔT values are determined, two modes of operation are possible. The first operating mode is to use the PDFA 4 as a real-time cross correlator during the active GCR-Window and a ghost cancellation filter for the inactive GCR-Window. This requires that the video signal be bypassed during the GCR-Window period. The second operating mode is to use the MACB correlator 6 to calculate the cross correlation between the stored GCR signal and the captured GCR signal off-line. By calculating "WinSize" points of the cross correlation, the GCR signal can be captured during the active GCR-Window period, and all relevant points of the cross correlation can be calculated by the MAC based correlator 6 before the next active GCR-Window period. In both cases, if a correlation peak is not detected, the INIT signal is activated and the circuit initializes from the same point as at power-up. If a correlation peak is detected, then the GCR-Present signal is asserted, which signals the μP to use the last captured GCR signal in the next averaging iteration. The advantage of using the MACB correlator 6 to perform the Windowed GCR synchronization function is that no video signal is bypassed.
FIG. 2 shows a block diagram of the GCR synchronization circuit 8 of the circuit of FIG. 1. The correlation signal, received at input 10, is applied to a first input 14 of a first multiplexer 12. The correlation signal is also applied, through a delay circuit 20, to a first input 24 of a second multiplexer 22. A threshold generator 32 applies a minimum threshold signal to a second input 16 of the first multiplexer 12 and a second input 26 of the second multiplexer 22.
An output 18 of the first multiplexer 12 is applied to a first input 36 of a first magnitude comparator 34. An output 30 of the second multiplexer 22 is applied to a D input of a peak register 42 having a Q output 44 connected to a second input 38 of the first magnitude comparator 34. The output 44 of the peak register 42 is also applied to a first input 48 of an first adder circuit 46, and, via a divide-by-2 divider 54, to a second input 50 of the first adder 46. An output 52 from the first adder 46 is applied to a third input 28 of the second multiplexer 22.
An output 40 from the first magnitude comparator 34 is applied to a threshold-GT signal input of a state machine 54. The state machine 54 determines the presence of the GCR signal and generates a GCR-Present signal, a GCR-Window signal, an initialization signal (INIT), and a correlation mode (CorrMode) signal. In addition, the state machine 54 generates an up/down count (Count-UD) signal, a Count-CE count enable signal, and a count-LE latch enable signal. These signals are applied to an up/down switching input of a counter 56, and to a CE input and LE input thereof, respectively.
A search value generator 58 applies a search value signal to a first input 62 of a third multiplexer 60 which receives a zero signal on its second input 64 from a zero signal generator 70. An output 68 of the third multiplexer 60 is applied to a count value (LOAD-VAL) input of the counter 56.
A count value output of the counter 56 is applied to a first input 74 of a second magnitude comparator 72, a first input 82 of a third magnitude comparator 80, a count value input of the state machine 54, and a first input 90 of a second adder 88, a second input 92 of the second adder 88 receiving the output from a GCR-End signal generator 96, and an output 94 from the second adder being applied to a D input of a delta T register 98.
A delta T register latch enable signal LE is generated by the state machine 54 and is applied to the LE clock input of the delta T register 98. A Q output from the delta T register 98 is applied to the second input 76 of the second magnitude comparator 72 and to the first input 102 of a subtractor 100. A second input 104 of the subtractor 100 receives the output from a GCR-Len signal generator 108, and an output 106 from the subtractor 100 is applied to the second input 84 of the third magnitude comparator 80.
An output 78 of the second magnitude comparator 72 and an output 86 of the third magnitude comparator 80 are connected, respectively, to first and second inputs of an AND-gate 108, an output thereof being connected to a window signal input of the state machine 54.
The state machine 54 further generates a threshold comparison selection signal for switching the first multiplexer 12, a threshold register selection signal for switching the second multiplexer 22, a threshold register LE latch enable signal for the peak register 42, and a load value selection signal for switching the third multiplexer 60.
FIG. 3 shows a flowchart of the operation of the GCR synchronization circuit 8, and, in particular, the state machine 54. After starting in block 200, initialization is instituted in block 202 in which the count value in the counter 56 is set to the search value, the peak register 42 is set to the threshold minimum and the correlation mode signal is set to be active. In block 204, a decision is made as to whether the correlation input signal is greater than the value in the peak register 42. If so, the current correlation input signal value is inputted into the peak register 42 in block 206 and the count value in the counter 56 is decremented in block 208. If not, the program proceeds directly to block 208 in which the count value in the counter 56 is decremented. Next, in block 210, it is determined whether the count value in the counter 56 is equal to zero. If not, the program reverts back to block 204 where the current correlation input signal is compared to the value in the peak register 42. If so, in block 212, the value in the peak register 42 is compared with the threshold minimum generated by the threshold generator 32. If this value is not equal to the threshold minimum, the program reverts to the initialization block 202. If so, in block 214, the peak register 42 is set equal to 3/4 of its previous value via the divider 54 and the first adder 46.
The program then proceeds to block 216 in which the correlation input value is compared to the current value in the peak register 42. If the correlation input signal value is less than or equal to the current value in the peak register 42, in block 218, the count value in the counter 56 is incremented and, in block 220, it is determined whether the current count value in the counter 56 is equal to a predetermined maximum value. If so, the program reverts to block 202, while if not, the program reverts to block 216.
If, in block 216, the correlation input signal value is greater than the current value in the peak register 42, the count value in the counter 56 is set equal to zero in block 222, and in block 224, it is determined if the current count value is greater than a predetermined delay. If not, in block 226, the count value in counter 56 is incremented and the program reverts to block 224. If so, in block 228, the correlation input signal is compared to the current value in the peak register 42. If the current value of the correlation input signal is less than or equal to the current value in the peak register 42, the count value in the counter 56 is incremented in block 230 and then the current count value in the counter 56 is compared to the predetermined maximum value in block 232. If the current count value in the counter 56 is less than the predetermined maximum value, the program reverts to block 228. If the current count value in the counter 56 is equal to the predetermined maximum value, the program reverts to block 202.
If in block 228, the current value of the correlation input signal is greater than the current value in the peak register 42, in block 234, the delta T register 72 is set equal to the count value in the counter 56 plus the GCR-End signal. Then, in block 236, the GCR synchronization signal is windowed. The program then reverts to the initialization block 202.
The procedure for the windowing of the GCR sync. using the PDFA 4 is shown in the flowchart of FIG. 4. After starting in block 300, the correlation mode signal is set to be inactive and the counter 56 is set to zero in block 302. Next, in block 304, it is determined whether there is a rising edge in the GCR-Window signal. If not, the count value in the counter 56 is incremented in block 306 and the program reverts to block 304. If so, the correlation mode signal is set to be active in block 308, and then, in block 310, a decision is made as to whether the Threshold-GT signal is active. If so, in block 312, a signal is generated indicating that the GCR is present and then in block 314, it is determined whether there is a falling edge in the GCR-Window signal. If not, in block 316, the count value in the counter 56 is incremented and the program reverts to block 314. If so, the program reverts to the block 302. If, in block 310, it is determined that the Threshold-GT signal is not active, the count value in the counter 56 is incremented in block 318 and in block 320, it is determined whether a falling edge is in the GCR-Window signal. If not, the program reverts to block 310. If so, in block 322, an initialization signal is generated and the program is exited at block 324.
The procedure for the windowing of the GCR sync. using the MACB correlator 6 is shown in FIG. 5. After starting in block 400, in block 402, the count value in the counter 56 is set to zero. Then in block 404, it is determined whether there is a rising edge in the GCR-Window signal. If not, the count value in the counter 56 is incremented in block 406 and then the program reverts to block 404. If so, in block 408, it is determined whether there is a falling edge in the GCR-Window signal. If not, the count value in the counter 56 is incremented in block 410 and the program goes back to block 406. If so, in block 412, the count value in counter 56 is set to zero and, in block 414, it is determined whether the Threshold-GT signal is active. If so, then in block 416, a signal is generated indicating that the GCR is present and then the program reverts to block 406. If not, it is determined whether there is a rising edge in the GCR-Window signal in block 418. If not, in block 420, the count value in the counter 56 is incremented and the program reverts to block 414. If so, in block 422, an initialization signal is generated and the program is exited at block 424.
FIG. 6 shows a block diagram of the MACB correlator 6. The GCR-Window signal is applied to a state machine 600 which selectively applies an n-CE signal and an n-RST signal, and an m-CE signal and an m-RST signal to respective inputs of an n index counter 602 and an m index counter 604. The count output from the n index counter 602 is applied to a CompVal input of a range comparator 606 which receives the signal WinSize/2 from a generator 608 at a RangeLow input. The count output from the n index counter 602 and the WinSize/2 signal from generator 608 are also applied to respective inputs of a calculation processor 610. The count output from the m index counter 604 is applied to a m-count input of the calculation processor 610, and to a first input of all equality comparator 612. A second input of the equality comparator 612 receives the WinSize signal from a generator 614 and applies its output to an m-done input of the state machine 600.
The calculation processor 610 performs the following calculations:
m1=GCR-Len-|m-count-WinSize/2|;
and
m2=n-count+m-count-WinSize/2.
A first output from the calculation processor 610, carrying the signal m1, is applied to a RangeHigh input of the range comparator 606 which applies an InRange signal at its output to an InRange input of the state machine 600.
A multiplexer 616 receives the output from the A/D converter 1 at a first input and a zero signal at a second input. The state machine 600 applies a RAMDataSel signal to a switching input of the multiplexer 616. An output from the multiplexer 616 is applied to a data input of a GCR capture RAM 618, which receives, at its address input, the output signal from the n index counter. An R/W (read or write) signal is applied by the state machine to an R/W input of the RAM 618, while an output from the RAM 618 is applied to an A input of an accumulation processor 620.
A second output from the calculation processor 610, carrying the signal m2, is applied to the address input of a GCR-ROM 622 which applies its DataOut signal to a B input of the accumulation processor 620. The state machine applies an ACC-EN signal and an ACC-RST signal to the accumulation processor 620.
The accumulation processor 620 determines the calculation MACC=MACC+A*B, which is applied to its output as the correlation output.
FIG. 7 shows the procedure for capturing the zero padded GCR. After POWER ON in block 700, the n-RST signal, the m-RST signal and the ACC-RST signal are made active in block 702. Then, in block 704, it is determined whether there is a rising edge in the GCR-Window signal. If not, the program reverts to block 704. If so, in block 706, the n-CE signal and the RAM-WE signal are made active. Next, in block 708, it is determined whether the n-count is in range. If not, the zero pad value is stored in the GCR-RAM in block 710, while if so, the GCR values are stored in the GCR-RAM in block 712. In either case, the program then proceeds to block 714 where it is determined whether the GCR-Window signal is active. If so, the program reverts to block 706, while in the alternative, in block 716, the n-RST signal is made active and the RAM-WE signal is made inactive. The program then proceeds to the correlation process in block 718 and then reverts to block 702.
FIG. 8 shows the procedure for correlation of WinSize points of cross correlation. After starting at block 800, the n-CE signal is made active in block 802. In block 804, it is determined whether the n-count is in range. If not, the program reverts to block 802. If so, the ACC-EN signal is made active in block 806. In block 808, it is determined whether the n-count is in range. If so, the program reverts to block 806. If not, in block 810, it is determined whether the m-done signal is active, if not, in block 812, the ACC-RST signal, the m-CE signal and the n-RST signal are made active and the program reverts to block 802. If so, the program exits at block 814.
Numerous alterations and modifications of the structure herein disclosed will present themselves to those skilled in the art. However, it is to be understood that the above described embodiment is for purposes of illustration only and not to be construed as a limitation of the invention. All such modifications which do not depart from the spirit of the invention are intended to be included within the scope of the appended claims. | A circuit for detecting and synchronizing a ghost cancellation reference (GCR) signal in a television video signal, includes a circuit for receiving at least one field of an input video signal, a circuit for finding a maximum correlation peak value in a field of said input video signal, a circuit for scaling the maximum correlation peak value to a lower predetermined value for detection for forming a scaled peak value, a circuit for synchronizing a next field of the video signal using the scaled peak value, and a circuit for predicting a future position of the GCR signal. | 7 |
FILING DATA
[0001] This application is associated with and claims priority from U.S. Provisional Patent Application No. 61/139,354, filed on 19 Dec. 2008, entitled “A Plant”, the entire contents of which, are incorporated herein by reference.
FIELD
[0002] The present invention relates generally to the field of genetic modification of plants. More particularly, the present invention is directed to genetically modified plants expressing desired color phenotypes.
BACKGROUND
[0003] Bibliographic details of the publications referred to by the author in this specification are collected at the end of the description.
[0004] Reference to any prior art in this specification is not, and should not be taken as, an acknowledgment or any form of suggestion that this prior art forms part of the common general knowledge in any country.
[0005] The flower or ornamental or horticultural plant industry strives to develop new and different varieties of flowers and/or plants. An effective way to create such novel varieties is through the manipulation of flower color. Classical breeding techniques have been used with some success to produce a wide range of colors for almost all of the commercial varieties of flowers and/or plants available today. This approach has been limited, however, by the constraints of a particular species' gene pool and for this reason it is rare for a single species to have the full spectrum of colored varieties. For example, the development of novel colored varieties of plants or plant parts such as flowers, foliage, fruits and stems would offer a significant opportunity in both the cut flower, ornamental and horticultural markets. In the flower or ornamental or horticultural plant industry, the development of novel colored varieties of carnation is of particular interest. This includes not only different colored flowers but also anthers and styles.
[0006] Flower color is predominantly due to three types of pigment: flavonoids, carotenoids and betalains. Of the three, the flavonoids are the most common and contribute a range of colors from yellow to red to blue. The flavonoid molecules that make the major contribution to flower color are the anthocyanins, which are glycosylated derivatives of cyanidin and its methylated derivative peonidin, delphinidin and its methylated derivatives petunidin and malvidin and pelargonidin. Anthocyanins are localized in the vacuole of the epidermal cells of petals or the vacuole of the sub epidermal cells of leaves.
[0007] The flavonoid pigments are secondary metabolites of the phenylpropanoid pathway. The biosynthetic pathway for the flavonoid pigments (flavonoid pathway) is well established (Holton and Cornish, Plant Cell 7:1071-1083, 1995; Mol et al, Trends Plant Sci. 3:212-217, 1998; Winkel-Shirley, Plant Physiol. 126:485-493, 2001a; and Winkel-Shirley, Plant Physiol. 127:1399-1404, 2001b, Tanaka and Mason, In Plant Genetic Engineering , Singh and Jaiwal (eds) SciTech Publishing Llc., USA, 1:361-385, 2003, Tanaka et al, Plant Cell, Tissue and Organ Culture 80:1-24, 2005, Tanaka and Brugliera, In Flowering and Its Manipulation, Annual Plant Reviews Ainsworth (ed), Blackwell Publishing, UK, 20:201-239, 2006) and is shown in FIG. 1 . Three reactions and enzymes are involved in the conversion of phenylalanine to p-coumaroyl-CoA, one of the first key substrates in the flavonoid pathway. The enzymes are phenylalanine ammonia-lyase (PAL), cinnamate 4-hydroxylase (C4H) and 4-coumarate: CoA ligase (4CL). The first committed step in the pathway involves the condensation of three molecules of malonyl-CoA (provided by the action of acetyl CoA carboxylase (ACC) on acetyl CoA and CO 2 ) with one molecule of p-coumaroyl-CoA. This reaction is catalyzed by the enzyme chalcone synthase (CHS). The product of this reaction, 2′,4,4′,6′, tetrahydroxy-chalcone, is normally rapidly isomerized by the enzyme chalcone flavanone isomerase (CHI) to produce naringenin. Naringenin is subsequently hydroxylated at the 3 position of the central ring by flavanone 3-hydroxylase (F3H) to produce dihydrokaempferol (DHK).
[0008] The pattern of hydroxylation of the B-ring of DHK plays a key role in determining petal color. The B-ring can be hydroxylated at either the 3′, or both the 3′ and 5′ positions, to produce dihydroquercetin (DHQ) or dihydromyricetin (DHM), respectively. Two key enzymes involved in this part of the pathway are the flavonoid 3′ hydroxylase (F3′H) and flavonoid 3′,5′ hydroxylase (F3′5′H), both members of the cytochrome P450 class of enzymes.
[0009] F3′H is a key enzyme in the flavonoid pathway leading to the cyanidin-based pigments which, in many plant species contribute to red and pink flower color. F3′5′H leads to the production of delphinidin based anthocyanins which, in many species contribute to the purple, violet and blue flower colors.
[0010] Nucleotide sequences encoding F3′5′Hs have been cloned (see International Patent Application No. PCT/AU92/00334 incorporated herein by reference and Holton et al, Nature, 366:276-279, 1993 and International Patent Application No. PCT/AU03/01111 incorporated herein by reference). These sequences were efficient in modulating 3′,5′ hydroxylation of flavonoids in petunia (see International Patent Application No. PCT/AU92/00334 and Holton et al, 1993 supra), tobacco (see International Patent Application No. PCT/AU92/00334), carnations (see International Patent Application No. PCT/AU96/00296 incorporated herein by reference) and roses (see International Patent Application No. PCT/AU03/01111).
[0011] The production of the colored anthocyanins from the dihydroflavonols (DHK, DHQ, DHM), involves dihydroflavonol-4-reductase (DFR) leading to the production of the leucoanthocyanidins. The leucoanthocyanidins are subsequently converted to the anthocyanidins, pelargonidin, cyanidin and delphinidin. These flavonoid molecules are unstable under normal physiological conditions and glycosylation at the 3-position, through the action of glycosyltransferases, stabilizes the anthocyanidin molecule thus allowing accumulation of the anthocyanins. In general, the glycosyltransferases transfer the sugar moieties from UDP sugars to the flavonoid molecules and show high specificities for the position of glycosylation and relatively low specificities for the acceptor substrates (Seitz and Hinderer, Anthocyanins. In: Cell Culture and Somatic Cell Genetics of Plants . Constabel and Vasil (eds.), Academic Press, New York, USA, 5:49-76, 1988). Anthocyanins can occur as 3-monosides, 3-biosides and 3-triosides as well as 3,5-diglycosides and 3,7-diglycosides associated with the sugars glucose, galactose, rhamnose, arabinose and xylose (Strack and Wray, In: The Flavonoids—Advances in Research since 1986. Harborne, J. B. (ed), Chapman and Hall, London, UK, 1-22, 1993).
[0012] Glycosyltransferases involved in the stabilization of the anthocyanidin molecule include UDP glucose: flavonoid 3-glucosyltransferase (3GT), which transfers a glucose moiety from UDP glucose to the 3-O-position of the anthocyanidin molecule to produce anthocyanidin 3-O-glucoside.
[0013] Many anthocyanidin glycosides exist in the form of acylated derivatives. The acyl groups that modify the anthocyanidin glycosides can be divided into two major classes based upon their structure. The aliphatic acyl groups include malonic acid or succinic acid and the aromatic class includes the hydroxy cinnamic acids such as p-coumaric acid, caffeic acid and ferulic acid and the benzoic acids such as p-hydroxybenzoic acid. For example in carnation the anthocyanins exist as malylated anthocyanins (Nakayama et al, Phytochemistry, 55, 937-939, 2000; Fukui et al, Phytochemistry, 63(1):15-23, 2003).
[0014] In addition to the above modifications, pH of the vacuole or compartment where pigments are localized and co-pigmentation with other flavonoids such as flavonols and flavones can affect petal color. Flavonols and flavones can also be aromatically acylated (Brouillard and Dangles, In: The Flavonoids—Advances in Research since 1986. Harborne, J. B. (ed), Chapman and Hall, London, UK, 1-22, 1993).
[0015] Carnation flowers can produce two types of anthocyanidins, depending on their genotype-pelargonidin and cyanidin. In the absence of F3′H activity, anthocyanins derived from pelargonidin are produced otherwise those derived from cyanidin are produced. Pelargonidin derived pigments are usually accompanied by kaempferol, a colorless flavonol. Cyanidin derived pigments are usually accompanied by both kaempferol and quercetin. Both pelargonidin and kaempferol are derived from DHK; both cyanidin and quercetin are derived from DHQ ( FIG. 1 ).
[0016] The substrate specificity shown by DFR regulates the anthocyanins that a plant accumulates. Petunia and cymbidium DFRs do not reduce DHK and thus they do not accumulate pelargonidin-based pigments (Forkmann and Ruhnau, Z Naturforsch C. 42c, 1146-1148, 1987, Johnson et al, Plant Journal, 19, 81-85, 1999). Many important floricultural species including iris, delphinium, cyclamen, gentian, cymbidium, nierembergia are presumed not to accumulate pelargonidin derived pigments due to the substrate specificity of their endogenous DFRs (Tanaka and Brugliera, 2006 supra).
[0017] In carnation, the DFR enzyme is capable of metabolizing DHK to leucopelargonidin, the precursor to pelargonidin-based pigments, giving rise to apricot to brick-red colored carnations and DHQ to leucocyanidin, the precursor to cyanidin-based pigments, producing pink to red carnations. Carnation DFR is also capable of converting DHM to leucodelphinidin (Forkmann and Ruhnau, 1987 supra), the precursor to delphinidin-based pigments. Wild-type or classically-derived carnation lines do not contain a F3′5′H enzyme and therefore do not synthesize DHM.
[0018] The petunia DFR enzyme has a different specificity to that of the carnation DFR. It is able to convert DHQ through to leucocyanidin, but it is not able to convert DHK to leucopelargonidin (Forkmann and Ruhnau, 1987 supra). It is also known that in petunia lines containing the F3′5′H enzyme, the petunia DFR enzyme can convert the DHM produced by this enzyme to leucodelphinidin which is further modified giving rise to delphinidin-based pigments which are predominantly responsible for blue colored flowers (see FIG. 1 ). Even though the petunia DFR is capable of converting both DHQ and DHM, it is able to convert DHM far more efficiently, thus favoring the production of delphinidin (Forkmann and Ruhnau, 1987 supra).
[0019] Carnations are one of the most extensively grown cut flowers in the world.
[0020] There are thousands of current and past cut-flower varieties of cultivated carnation. These are divided into three general groups based on plant form, flower size and flower type. The three flower types are standards, sprays and midis. Most of the carnations sold fall into two main groups—the standards and the sprays. Standard carnations are intended for cultivation under conditions in which a single large flower is required per stem. Side shoots and buds are removed (a process called disbudding) to increase the size of the terminal flower. Sprays and/or miniatures are intended for cultivation to give a large number of smaller flowers per stem. Only the central flower is removed, allowing the laterals to form a ‘fan’ of stems.
[0021] Spray carnation varieties are popular in the floral trade, as the multiple flower buds on a single stem are well suited to various types of flower arrangements and provide bulk to bouquets used in the mass market segment of the industry.
[0022] Standard and spray cultivars dominate the carnation cut-flower industry, with approximately equal numbers sold of each type in the USA. In Japan, Spray-type varieties account for 70% of carnation flowers sold by volume, whilst in Europe spray-type carnations account for approximately 50% of carnation flowers traded through out the Dutch auctions. The Dutch auction trade is a good indication of consumption across Europe.
[0023] Whilst standard and midi-type carnations have been successfully manipulated genetically to introduce new colors (Tanaka and Brugliera, 2006 supra; see also International Patent Application No. PCT/AU96/00296), this has not been applied to spray carnations. There has been absence of blue color in color-assortment in carnation, only recently filled through the introduction of genetically-modified standard-type carnation varieties. However, standard-type varieties can not be used for certain purposes, such as bouquets and flower arrangements where a large number of smaller carnation flowers are needed, such as hand-held arrangements, and small table settings.
[0024] One particular spray carnation which is particularly commercially popular is the Cerise Westpearl line of carnations ( Dianthus caryophyllus cv. Cerise Westpearl). The variety has excellent growing characteristics and a moderate to good resistance to fungal pathogens such as Fusarium . Cerise Westpearl is a sport of Westpearl. However, before the advent of the present invention, purple/blue spray carnations were not available.
[0025] White Unesco is a classically-derived carnation of the midi-type. It is white and does not normally produce anthocyanins primarily because the petals do not accumulate carnation DFR transcripts and so when White Unesco was transformed with Viola F3′5′H and a petunia DFR gene, over 80% of the anthocyanins produced were delphinidin based (see International Patent Application PCT/AU96/00296). Although this process has been useful in obtaining carnation lines with a purple/violet petals, it is limited to the identification of white lines that are mutant in the ability to accumulate petal carnation DFR mRNA or functional DFR enzymes in the petals but have the rest of the anthocyanin pathway intact so that the DHM produced can be converted to stable, colored anthocyanins. Of the 13 lines analyzed (see International Patent Application PCT/AU96/00296), only two were deficient in carnation DFR but intact in the ability to produce anthocyanins. Of the two, only one (White Uncesco) resulted in the production of purple/violet petals upon the introduction of F3′5′H and a petunia DFR.
[0026] The application of a similar approach using Viola F3′5′H and a petunia DFR transformed into a colored line such as Cerise Westpearl has not yielded significant novel colored products.
[0027] There is a need, therefore, to find an alternative means of producing novel colored purple/mauve flowers using colored lines such as Cerise Westpearl.
SUMMARY
[0028] Throughout this specification, unless the context requires otherwise, the word “comprise”, or variations such as “comprises” or “comprising”, will be understood to imply the inclusion of a stated element or integer or group of elements or integers but not the exclusion of any other element or integer or group of elements or integers.
[0029] Nucleotide and amino acid sequences are referred to by a sequence identifier number (SEQ ID NO). The SEQ ID NOs correspond numerically to the sequence identifiers <400>1 (SEQ ID NO:1), <400>2 (SEQ ID NO:2), etc.
[0030] A summary of sequence identifiers used throughout the subject specification is provided in Table 1.
[0031] The present invention provides genetically modified plants exhibiting altered inflorescence. More particularly, the present invention provides genetically modified carnations and even more particularly genetically modified carnation sprays exhibiting altered inflorescence. The altered inflorescence is a color in the range of red-purple to blue such as purple and mauve to blue color in the tissue or organelles including flowers, petals, anthers and styles. In one embodiment, the color is determined using the Royal Horticultural Society (RHS) color chart where colors are arranged in order of the fully saturated colors with the less saturated and less bright colors alongside. The color groups proceed through the observable spectrum and the colors referred to herein are generally in the red-purple (RHSCC 58-74), purple (RHSCC 75-79), purple-violet (RHSCC 81-82), violet (RHSCC 83-88), violet-blue (89-98), blue (RHSCC 99-110) groups contained in Fan 2. Colors are selected from the range including 61A, 64A, 71A, 71C, 72A, 81A, 86A and 87A and colors in between or proximal thereto.
[0032] Hence, the present invention is directed to a genetically modified plant including its progeny with purple/violet shades of color comprising a functional non-indigenous F3′,5′H, a functional DFR in petals and genetic material which down regulates expression of a plant's indigenous DFR gene.
[0033] In one embodiment, the genetic material comprises sense and anti-sense nucleotide sequences which correspond to the plant's indigenous DFR sequence (ds plantDFR). This induces hairpin RNAi (hpRNAi)-mediated silencing primarily via post-transcriptional gene silencing (PTGS). By “indigenous” is meant that an enzyme or a gene evolved in a plant, i.e. is normally resident in that plant. A “non-indigenous” enzyme or gene means that a gene or other genetic material was introduced into a plant or a parent of the plant by genetic angering or breeding practices.
[0034] In an embodiment, the plant is a carnation such as a spray carnation and the indigenous DFR is the carnation DFR. The genetic material is a chimeric construct referred to as ds carnDFR.
[0035] In an embodiment, the plant and its progeny, further comprise genetic material encoding a non-indigenous S adenosylmethionine: anthocyanin 3′,5′ methyltransferase (3′5′ AMT) and/or a non-indigenous flavone synthase (FNS).
[0036] In a further embodiment the 3′5′ AMT is from Torenia (ThMT) and the FNS is from Torenia (ThFNS).
[0037] The modified plants and in particular genetically modified spray carnations comprise genetic sequences encoding at least one F3′5′H enzyme and at least one DFR enzyme and express at least one ds plantDFR molecule. Insofar as the present invention relates to carnations, the ds plantDFR is ds carnDFR and the carnation sprays are conveniently in a Cerise Westpearl genetic background including the progenitor of Cerise Westpearl such as Westpearl. Other carnation cultivars included within the present invention are colored varieties such as Cinderella, Kortina Chanel, Vega, Artisan, Miledy, Barbara, Dark Rendezvous. Other plants contemplated herein include chrysanthemums, roses, gerberas, lisianthus, tulip, lily, geranium, petunia, iris, Torenia, Begonia, Cyclamen, Nierembergia, Catharanthus, Pelargonium , orchid, grape, apple, Euphorbia, Fuchsia and other ornamental or horticultural plants.
[0038] One aspect of the present invention is directed to a genetically modified plant exhibiting altered inflorescence in selected tissue, the plant comprising expressed genetic material encoding at least one F3′5′H enzyme and at least one DFR enzyme and expressing genetic material which down regulates a DFR gene. More particularly, the present invention provides a genetically modified plant exhibiting altered inflorescence, the plant or its progeny comprising expressed genetic material encoding at least one non-indigenous F3′5′H enzyme and at least one non-indigenous DFR enzyme and expressing genetic material which down regulates expression of the plant's indigenous DFR gene. In an embodiment, the plant and its progeny, further comprise genetic material encoding a non-indigenous ThMT. In a particular embodiment, the genetic material which down regulates the indigenous DFR gene comprises sense and anti-sense nucleotide sequence corresponding to the indigenous DFR gene or its mRNA (“ds plantDFR”). The term “altered inflorescence” in this context means compared to the inflorescence of a plant (e.g. parent plant or plant of the same species) prior to genetic manipulation. The term “encoding” includes the expression of the genetic material to produce functional F3′5′H and DFR enzymes.
[0039] A “ds plantDFR molecule” is genetic material comprising both sense and anti-sense fragments of a plant is indigenous DFR genomic or cDNA sequence or corresponding mRNA. The ds plantDFR is expressed to induce hpRNAi-mediated gene silencing of an indigenous DFR gene. In a particular embodiment, the plant is carnation and the ds plantDFR molecule is ds carnDFR.
[0040] In a particular embodiment, the plant is a spray carnation.
[0041] Accordingly, another aspect of the present invention is directed to a spray carnation plant exhibiting altered inflorescence in selected tissue, the spray carnation comprising expressed genetic material encoding at least one non-indigenous F3′5′H enzyme and at least one non-indigenous DFR enzyme and expressing at least one ds carnDFR molecule which down regulates expression of the plant's indigenous DFR gene.
[0042] Yet another, aspect of the present invention is directed to a genetically modified Cerise Westpearl spray carnation plant or sport thereof exhibiting tissues of a purple to blue color, the carnation comprising expressed genetic sequences encoding at least one non-indigenous F3′5′H enzyme and at least one non-indigenous DFR enzyme and expressing at least one ds carnDFR molecule which down regulates expression of the plant's indigenous DFR gene.
[0043] Another aspect of the present invention is directed to a genetically modified chrysanthemum plant exhibiting tissues of a purple to blue color, the chrysanthemum comprising expressed genetic sequences encoding at least one non-indigenous F3′5′H enzyme and at least one non-indigenous DFR enzyme and expressing at least one ds chrysDFR molecule which down regulates expression of the plant's indigenous DFR gene.
[0044] Still another aspect of the present invention is directed to a genetically modified rose plant exhibiting tissues of a purple to blue color, the rose comprising expressed genetic sequences encoding at least one non-indigenous F3′5′H enzyme and at least one non-indigenous DFR enzyme and at least one ds roseDFR molecule which down regulates expression of the plant's indigenous DFR gene.
[0045] Even yet another aspect of the present invention is directed to a genetically modified gerbera plant exhibiting tissues of a purple to blue color, the gerbera comprising expressed genetic sequences encoding at least one non-indigenous F3′5′H enzyme and at least one non-indigenous DFR enzyme and at least one ds gerbDFR molecule which down regulates expression of the plant's indigenous DFR gene.
[0046] Yet another aspect of the present invention is directed to a genetically modified ornamental or horticultural plant exhibiting tissues of a purple to blue color, the ornamental or horticultural plant comprising expressed genetic sequences encoding at least one non-indigenous F3′5′H enzyme and at least one non-indigenous DFR enzyme and incorporation of at least one ds plantDFR molecule which down regulates expression of the plant's indigenous DFR gene.
[0047] In an embodiment, the plant and its progeny, further comprise genetic material encoding a non-indigenous ThMT and/or a non-indigenous ThFNS. Reference to “purple to blue” includes mauve.
[0048] In a particular embodiment, the present invention provides a genetically modified spray carnation identified herein as Cerise Westpearl (CW)/pCGP3366 and its progeny and sports. In another embodiment, the present invention provides a genetically modified spray carnation identified herein as Cerise Westpearl (CW)/pCGP3601 and its progeny and sports. In yet another embodiment, the present invention provides a genetically modified spray carnation identified herein as Cerise Westpearl (CW)/pCGP3605 and its progeny and sports. Still in another embodiment, the present invention provides a genetically modified spray carnation identified herein as Cerise Westpearl (CW)/pCGP3616 and its progeny and sports. Even in yet another embodiment, the present invention provides a genetically modified spray carnation identified herein as Cerise Westpearl (CW)/pCGP3607 and its progeny and sports.
[0049] Progeny, reproductive material, cut flowers, tissue culturable cells and regenerable cells from the genetically plants also form part of the present invention.
[0050] The present invention further provides for the use of genetic sequences encoding at least one non-indigenous F3′5′H enzyme and at least one non-indigenous DFR enzyme and genetic material which down regulates a plant's indigenous DFR gene in the manufacture of a carnation or sports thereof exhibiting altered inflorescence including tissue having a purple to violet to blue color.
[0051] More particularly, the present invention is directed to the use of genetic sequences encoding at least one non-indigenous F3′5′H enzyme and at least one non-indigenous DFR enzyme and incorporation of at least one ds carnDFR molecule in the manufacture of a genetically modified plant such as a spray carnation including a Cerise Westpearl carnation or sports thereof exhibiting altered inflorescence including tissue having a purple to blue color.
[0052] The F3′5′H enzymes may be from any source. Nucleotide sequences encoding F3′5′H enzymes from Viola sp are particularly useful (see Table 1). Similarly, the nucleotide sequence encoding the DFR enzyme may come from any species such as but not limited to Petunia sp (e.g. see Table 1), iris, cyclamen, delphinium, gentian, Cymbidium , nierembergia The sense and anti-sense fragments forming the hairpin loop of the ds carnDFR comes from carnation. The intron in the ds carnDFR comes from petunia DFR-A intron 1 (Beld et al, Plant Mol. Biol. 13:491-502, 1989), however, any intron that is able to be processed in carnation can be used. In another embodiment no intron is used.
[0053] Suitable nucleotide sequences for F3′5′H from Viola sp., a DFR from Petunia sp and a DFR from Dianthus sp are set forth in Table 1.
[0000]
TABLE 1
Summary of sequence identifiers
SEQ ID
TYPE
NO:
NAME
SPECIES
OF SEQ
DESCRIPTION
1
BPF3′5′H#40.nt
Viola sp
nucleotide
F3′5′H cDNA
2
BPF3′5′H#40.aa
Viola sp
amino acid
deduced F3′5′H amino acid sequence
3
Pet gen DFR.nt
Petunia sp
nucleotide
DFR genomic clone
4
Pet gen DFR.aa
Petunia sp
amino acid
deduced DFR amino acid sequence
5
DFRint35S F
nucleotide
primer
6
DFRint35S R
nucleotide
primer
7
ds carnDFR F
nucleotide
primer
8
ds carnDFR R
nucleotide
primer
9
Carn DFR.nt
Dianthus
nucleotide
DFR cDNA
caryophyllus
10
Carn DFR.aa
Dianthus
amino acid
deduced DFR amino acid sequence
caryophyllus
11
ThMT.nt
Torenia sp.
nucleotide
3′5′ AMT cDNA
12
ThMT.aa
Torenia sp .
amino acid
deduced 3′5′ AMT amino acid sequence
13
ThFNS.nt
Torenia sp .
nucleotide
FNS cDNA
14
ThFNS.aa
Torenia sp.
amino acid
deduced FNS amino acid sequence
15
carnANS 5′
Dianthus
nucleotide
Carnation ANS promoter fragment
caryophyllus
16
carnANS 3′
Dianthus
nucleotide
Carnation ANS terminator fragment
caryophyllus
17
RoseCHS 5′
Rosa
hybrida
nucleotide
Rose CHS promoter fragment
[0054] BP, black pansy; nt, nucleotide; aa, amino acid; pet, petunia; carn, carnation; ThMT, S-adenosylmethionine: anthocyanin 3′,5′ methyltransferase from torenia; ANS, anthocyanin synthase; CHS, chalcone synthase; 3′5′ AMT, S-adenosylmethionine: anthocyanin 3′,5′ methyltransferase; FNS, flavone synthase; ThFNS, flavone synthase from torenia.
BRIEF DESCRIPTION OF THE FIGURES
[0055] FIG. 1 is a schematic representation of the biosynthesis pathway for the flavonoid pigments showing production of the anthocyanidin 3-glucosides that occur in most plants that produce anthocyanins. Enzymes involved in the pathway have been indicated as follows: PAL=Phenylalanine ammonia-lyase; C4H=Cinnamate 4-hydroxylase; 4CL=4-coumarate:CoA ligase; CHS=Chalcone synthase; CHI=Chalcone flavanone isomerase; F3H=Flavanone 3-hydroxylase; DFR=Dihydroflavonol-4-reductase; ANS=Anthocyanidin synthase, 3GT=UDP-glucose: flavonoid 3-O-glucosyltransferase; Other abbreviations include: DHK=dihydrokaempferol, DHQ=dihydroquercetin, DHM=dihydromyricetin.
[0056] FIG. 2 is a diagrammatic representation of the binary plasmid pCGP3360. chimeric. The construction of pCGP3360 is described in Example 1. Selected restriction endonuclease sites are marked. Abbreviations include LB=Left Border from A. tumefaciens Ti plasmid, RB=Right border region from A. tumefaciens Ti plasmid, TetR=antibiotic, tetracycline resistance gene complex. Refer to Table 2 for a description of gene elements.
[0057] FIG. 3 is a diagrammatic representation of the binary plasmid pCGP3366. chimeric. The construction of pCGP3366 is described in Example 1. Selected restriction endonuclease sites are marked. Abbreviations include LB=Left Border from A. tumefaciens Ti plasmid, RB=Right border region from A. tumefaciens Ti plasmid, TetR=antibiotic, tetracycline resistance gene complex. In this figure “ds carnDFR”=the CaMV 35S:ds carnDFR:35S 3′ expression cassette. Refer to Table 2 for a description of gene elements.
[0058] FIG. 4 is a diagrammatic representation of the binary plasmid pCGP3601. chimeric. The construction of pCGP3601 is described in Example 1. Abbreviations include LB=Left Border from A. tumefaciens Ti plasmid, RB=Right border region from A. tumefaciens Ti plasmid, TetR=antibiotic, tetracycline resistance gene complex. In this figure “ds carnDFR”=the CaMV 35S:ds carnDFR:35S 3′ expression cassette. Refer to Table 2 for a description of gene elements.
[0059] FIG. 5 is a diagrammatic representation of the binary plasmid pCGP3605. chimeric. The construction of pCGP3605 is described in Example 1. Abbreviations include LB=Left Border from A. tumefaciens Ti plasmid, RB=Right border region from A. tumefaciens Ti plasmid, TetR=antibiotic, tetracycline resistance gene complex. In this figure “ds carnDFR”=the CaMV 35S:ds carnDFR:35S 3′ expression cassette and “ThMt”=CaMV 35S:ThMT:35S 3′ expression cassette. Refer to Table 2 for a description of gene elements.
[0060] FIG. 6 is a diagrammatic representation of the binary plasmid pCGP3616. chimeric. The construction of pCGP3616 is described in Example 1. Abbreviations include LB=Left Border from A. tumefaciens Ti plasmid, RB=Right border region from A. tumefaciens Ti plasmid, TetR=antibiotic, tetracycline resistance gene complex. In this figure “ds carnDFR”=the CaMV 35S:ds carnDFR:35S 3′ expression cassette. Refer to Table 2 for a description of gene elements.
[0061] FIG. 7 is a diagrammatic representation of the binary plasmid pCGP3607. chimeric. The construction of pCGP3607 is described in Example 1. Abbreviations include LB=Left Border from A. tumefaciens Ti plasmid, RB=Right border region from A. tumefaciens Ti plasmid, TetR=antibiotic, tetracycline resistance gene complex. In this figure “ds carnDFR”=the CaMV 35S:ds carnDFR:35S 3′ expression cassette and “ThFNS”=e35S 5′:ThFNS:petD8 3′ expression cassette. Refer to Table 2 for a description of gene elements.
DETAILED DESCRIPTION
[0062] As used in the subject specification, the singular forms “a”, “an” and “the” include plural aspects unless the context clearly dictates otherwise. Thus, for example, reference to “a plant” includes a single plant, as well as two or more plants; reference to “an anther” includes a single anther as well as two or more anthers; reference to “the invention” includes a single aspect or multiple aspects of an invention; and so on.
[0063] The present invention contemplates genetically modified plants such as carnation plants and in particular spray carnations exhibiting altered inflorescence. The altered inflorescence may be in any tissue or organelle including flowers, petals, anthers and styles. Particular inflorescence contemplated herein includes a color in the range of red-purple to blue color such as a purple to blue color including mauve. The color determination is conveniently measured against the Royal Horticultural Society (RHS) color chart (RHSCC) and includes colors 77A, 77B, N80B, 81A, 81B, 82A, 82B, 88D and colors in between or proximal to either end of the above range. The term “inflorescence” is not to be narrowly construed and relates to any colored cells, tissues organelles or parts thereof, as well as flowers and petals.
[0064] Hence, one aspect of the present invention is directed to a genetically modified plant exhibiting altered inflorescence in selected tissue, the plant comprising expressed genetic material encoding at least one F3′5′H enzyme and at least one DFR enzyme and expressing genetic material which down regulates a plant's indigenous DFR gene. The “plant” includes a parent plant and its progeny which carry on the genetic modification. In particular, the present invention provides a genetically modified plant exhibiting altered inflorescence, the plant or its progeny comprising expressed genetic material encoding at least one non-indigenous flavonoid 3′,5′ hydroxylase (F3′5′H) enzyme and at least one non-indigenous dihydroflavonol 4-reductase (DFR) enzyme and expressing genetic material which down regulates expression of the plant's indigenous DFR gene.
[0065] In an embodiment, the plant and its progeny, further comprise genetic material encoding a non-indigenous S-adenosylmethionine: anthocyanin 3′,5′ methyltransferase (ThMT) and/or a flavone synthase (ThFNS). The genetic material which down regulates the plant's indigenous DFR gene comprises, in one embodiment, sense and anti-sense nucleotide sequences corresponding to the plant's indigenous DFR gene or mRNA (ds plantDFR).
[0066] The ds plantDFR molecule is a chimeric construct of sense and anti-sense genetic material from the DFR genomic DNA or cDNA corresponding to the indigenous DFR gene or its mRNA in the host plant. The “indigenous” DFR is the DFR normally resident in the host plant prior to genetic manipulation. A non-indigenous enzyme or gene includes a gene or other genetic material which has been introduced into a plant or a parent of the plant by genetic engineering or plant breeding practices.
[0067] The ds plantDFR molecule when expressed down-regulates via PTGS the DFR gene in the host plant. The ds plantDFR molecule may be from carnation (ds carnDFR), chrysanthemum (ds chrysDFR), rose (ds roseDFR), gerbera (ds gerbDFR), dianthus (ds dianDFR), petunia (ds petDFR) or from an ornamental or horticultural plant (ds plantDFR). Other ds plantDFR's may come from lisianthus, tulip, lily, geranium, petunia, iris, Torenia, Begonia, Cyclamen, Nierembergia, Catharanthus, Pelargonium , orchid, grape, apple, Euphorbia or Fuchsia.
[0068] In a particular embodiment, the plant is a carnation. Accordingly, another aspect of the present invention is directed to a spray carnation exhibiting altered inflorescence in selected tissue, the spray carnation comprising expressed genetic material encoding at least one non-indigenous F3′5′H enzyme and at least one non-indigenous DFR enzyme and expressing of at least one ds carnDFR molecule. The ds carnDFR, when expressed, down regulates expression of the plant's indigenous DFR gene.
[0069] In an embodiment, the plant and its progeny, further comprise genetic material encoding a non-indigenous ThMT and/or ThFNS.
[0070] Hence, a further aspect of the present invention is directed to a spray carnation exhibiting altered inflorescence in selected tissue, the spray carnation comprising expressed genetic material encoding at least one non-indigenous F3′5′H enzyme, at least one non-indigenous DFR enzyme and at least one non-indigenous ThMT and/or ThFNS and expressing of at least one ds carnDFR molecule.
[0071] Whilst the present invention encompasses any spray carnation, a carnation of the Cerise Westpearl line is particularly useful including sports thereof. Useful sports of Cerise Westpearl include Westpearl.
[0072] Accordingly, another aspect of the present invention is directed to a genetically modified Cerise Westpearl spray carnation plant line or sports thereof exhibiting tissues of a purple to blue color, the carnation comprising expressed genetic sequences encoding at least one non-indigenous F3′5′H enzyme and at least one non-indigenous DFR enzyme and expressing at least one ds carnDFR molecule which down regulates expression of the plant's indigenous DFR gene.
[0073] More particularly, the present invention provides a genetically modified Cerise Westpearl plant (CW)/pCGP3366 (also referred to as CW/3366 or Cerise Westpearl/3366) line exhibiting altered inflorescence, the line comprising an expressed genetic sequence encoding at least one non-indigenous F3′5′H enzyme and at least one non-indigenous DFR enzyme and expressing at least one ds carnDFR molecule which down regulates expression of the plant's indigenous DFR gene.
[0074] Even more particularly, the present invention provides a genetically modified Cerise Westpearl plant (CW)/pCGP3601 (also referred to as CW/3601 or Cerise Westpearl/3601) line exhibiting altered inflorescence, the line comprising an expressed genetic sequence encoding at least one non-indigenous F3′5′H enzyme and at least one non-indigenous DFR enzyme and expressing at least one ds carnDFR molecule which down regulates expression of the plant's indigenous DFR gene.
[0075] Still more particularly, the present invention provides a genetically modified Cerise Westpearl plant (CW)/pCGP3605 (also referred to as CW/3605 or Cerise Westpearl/3605) line exhibiting altered inflorescence, the line comprising an expressed genetic sequence encoding at least one non-indigenous F3′5′H enzyme and at least one non-indigenous DFR enzyme and expressing at least one ds carnDFR molecule which down regulates expression of the plant's indigenous DFR gene.
[0076] Even still more particularly, the present invention provides a genetically modified Cerise Westpearl plant (CW)/pCGP3616 (also referred to as CW/3616 or Cerise Westpearl/3616) line exhibiting altered inflorescence, the line comprising an expressed genetic sequence encoding at least one non-indigenous F3′5′H enzyme and at least one non-indigenous DFR enzyme and expressing at least one ds carnDFR molecule which down regulates expression of the plant's indigenous DFR gene.
[0077] Yet more particularly, the present invention provides a genetically modified Cerise Westpearl plant (CW)/pCGP3607 (also referred to as CW/3607 or Cerise Westpearl/3607) line exhibiting altered inflorescence, the line comprising an expressed genetic sequence encoding at least one non-indigenous F3′5′H enzyme and at least one non-indigenous DFR enzyme and expressing at least one ds carnDFR molecule which down regulates expression of the plant's indigenous DFR gene.
[0078] In each of the above-mentioned aspects, the plant and its progeny may further comprise genetic material encoding a non-indigenous ThMT and/or ThFNS.
[0079] Examples of Cerise Westpearl transgenic lines include #25958 (FLORIGENE Moonberry (Trade mark)) and line #25947 (FLORIGENE Moonpearl (Trade mark)).
[0080] Additional genetically modified carnations contemplated herein include the spray carnations Westpearl, Kortina Chanel, Vega, Barbara and Artisan and the standard carnations Cinderella, Dark Rendezvous, Miledy.
[0081] Other genetically modified plants contemplated herein include chrysanthemums, roses, gerberas, lisianthus, tulip, lily, geranium, petunia, iris, Torenia, Begonia, Cyclamen, Nierembergia, Catharanthus, Pelargonium , orchid, grape, apple, Euphorbia or Fuchsia and other ornamental or horticultural plants.
[0082] Another aspect of the present invention is directed to a genetically modified chrysanthemum plant exhibiting tissues of a purple to blue color, the chrysanthemum comprising expressed genetic sequences encoding at least one non-indigenous F3′5′H enzyme and at least one non-indigenous DFR enzyme and expressing at least one ds chrysDFR molecule which down regulates expression of the plant's indigenous DFR gene.
[0083] Still another aspect of the present invention is directed to a genetically modified rose plant exhibiting tissues of a purple to blue color, the rose comprising expressed genetic sequences encoding at least one non-indigenous F3′5′H enzyme and at least one non-indigenous DFR enzyme and expressing at least one ds roseDFR molecule which down regulates expression of the plant's indigenous DFR gene.
[0084] Yet another aspect of the present invention is directed to a genetically modified gerbera plant exhibiting tissues of a purple to blue color, the gerbera comprising expressed genetic sequences encoding at least one F3′5′H enzyme and at least one DFR enzyme and expressing at least one ds gerbDFR molecule which down regulates expression of the plant's indigenous DFR gene.
[0085] Yet another aspect of the present invention is directed to a genetically modified ornamental or horticultural plant exhibiting tissues of a purple to blue color, the ornamental or horticultural plant comprising expressed genetic sequences encoding at least one non-indigenous F3′5′H enzyme and at least one DFR enzyme and expressing at least one ds plantDFR molecule which down regulates expression of the plant's indigenous DFR gene.
[0086] In an embodiment, the plant and its progeny, further comprise genetic material encoding a non-indigenous ThMT and/or ThFNS. The term “purple to blue color” includes mauve.
[0087] The ds plantDFR, ds chrysDFR, ds roseDFR, ds gerbDFR, ds petDFR and ds dianDFR comprise sense and anti-sense genomic or cDNA fragments of the gene encoding the host plant's DFR. Expression of this molecule results in down-regulation of the indigenous DFR gene in the host plant. Similar comments apply in relation to ds plantDFR's from other host plants.
[0088] The genetic sequence may be a single construct carrying the nucleotide sequences encoding the F3′5′H enzymes and the DFR enzyme or multiple genetic constructs may be employed. In addition, the genetic sequences may be integrated into the genome of a plant cell or it may be maintained as an extra-chromosomal artificial chromosome. Still furthermore, the generation of a spray carnation expressing at least one F3′5′H enzyme and at least one DFR enzyme and expressing at least one ds carnDFR molecule may be generated by recombinant means alone or by a combination of conventional breeding and recombinant DNA manipulation. The genetic sequences are “expressed” in the sense of being operably linked to a promoter and other regulatory sequences resulting in transcription and translation to produce F3′5′H and DFR enzymes.
[0089] Hence, another aspect of the present invention contemplates a method for producing a genetically modified plant such as a spray carnation exhibiting altered inflorescence, the method comprising introducing into regenerable cells of a plant such as a spray carnation plant expressible genetic material encoding at least one non-indigenous F3′5′H enzyme and at least one non-indigenous DFR enzyme and incorporation of at least one ds carnDFR molecule which down regulates expression of the plant's indigenous DFR gene and regenerating a plant therefrom or obtaining progeny from the regenerated plant.
[0090] In an embodiment, the plant and its progeny, further comprise genetic material encoding a non-indigenous ThMT and/or ThFNS.
[0091] Similar methodologies are contemplated herein from chrysanthemums, rose, gerbera and ornamental plants.
[0092] The plant may then undergo various generations of growth or cultivation. Hence, reference to a genetically modified spray carnation includes progeny thereof and sister lines thereof as well as sports thereof.
[0093] Another aspect of the present invention provides a method for producing a genetically modified plant such as a spray carnation line exhibiting altered inflorescence, the method comprising selecting a plant such as a spray carnation comprising expressible genetic material encoding at least one non-indigenous F3′5′H enzyme and at least one DFR enzyme and incorporation of at least one ds carnDFR molecule which down regulates expression of the plant's indigenous DFR gene and crossing this plant with another plant such as a spray carnation comprising genetic material encoding the other of at least one F3′5′H enzyme and at least one non-indigenous DFR enzyme and incorporation of at least one ds carnDFR molecule and then selecting F1 or subsequent generation plants which express the genetic material.
[0094] In an embodiment, the plant and its progeny, further comprise genetic material encoding a non-indigenous ThMT and/or ThFNS.
[0095] Nucleotide sequences encoding non-indigenous F3′5′H and DFR enzymes relative to a host plant may be from any source including Viola sp, Petunia sp, Salvia sp, Lisianthus sp, Gentiana sp, Sollya sp, Clitoria sp, Kennedia sp, Campanula sp, Lavandula sp, Verbena sp, Torenia sp, Delphinium sp, Solanum sp, Cineraria sp, Vitis sp, Babiana stricta, Pinus sp, Picea sp, Larix sp, Phaseolus sp, Vaccinium sp, Cyclamen sp, Iris sp, Pelargonium sp, Liparieae, Geranium sp, Pisum sp, Lathyrus sp, Catharanthus sp, Malvia sp, Mucuna sp, Vicia sp, Saintpaulia sp, Lagerstroemia sp, Tibouchina sp, Plumbago sp, Hypocalyptus sp, Rhododendron sp, Linum sp, Macroptilium sp, Hibiscus sp, Hydrangea sp, Cymbidium sp, Millettia sp, Hedysarum sp, Lespedeza sp, Asparagus sp, Antigonon sp, Pisum sp, Freesia sp, Brunella sp or Clarkia sp, etc. For example, in one embodiment, the F3′5′H enzyme comes from Viola sp.
[0096] The DFR may come again from the same or different plant species. For example in one embodiment the DFR enzyme comes from petunia. In another embodiment the DFR comes from iris.
[0097] The sense and anti-sense fragments forming the hairpin loop of the ds carnDFR comes from carnation (EMBL accession number Z67983, GenBank accession number gi: 1067126) or the functional equivalent from chrysanthemum, rose, gerbera or ornamental plant. Since the aim of the ds carnDFR is to down regulate the indigenous carnation DFR gene via RNAi mediated silencing various fragments of the endogenous carnation DFR sequence may be used (see International Patent Application No. PCT/IB99/00606, Wesley et al, Plant J, 27, 581-590, 2001, Ossowski et al, Plant J, 53, 674-690, 2008). For example, in one embodiment a 300 bp fragment is used in a sense and anti-sense direction. The intron in the ds carnDFR comes from petunia DFR-A intron 1 (Beld et al, Plant Mol. Biol. 13:491-502, 1989), however, any intron that is able to be processed in carnation can be used. In another embodiment, no intron is used. Again, the same comments apply for ds plantDFR molecules generically.
[0098] The present invention provides for the use of genetic sequences encoding at least one non-indigenous F3′5′H enzyme and at least one non-indigenous DFR enzyme and incorporation of genetic material which down regulates a plant's indigenous DFR gene in the manufacture of a carnation or sports thereof exhibiting altered inflorescence including tissue having a purple to violet to blue color.
[0099] The present invention also contemplates the use of genetic sequences encoding at least one non-indigenous F3′5′H enzyme and at least one non-indigenous DFR enzyme and incorporation of at least one ds carnDFR molecule in the manufacture of a spray carnation plant such as a Cerise Westpearl carnation or sports thereof exhibiting altered inflorescence including tissue having a purple to blue color.
[0100] In another embodiment, the present invention contemplates the use of genetic sequences encoding at least one non-indigenous F3′5′H enzyme and at least one non-indigenous DFR enzyme and incorporation of at least one ds DFR (directed at silencing of the indigenous DFR gene) molecule in the manufacture of a genetically modified plant selected from a rose, chrysanthemum, gerbera, tulip, lily, orchid, lisianthus, begonia, torenia, geranium, petunia, nierembergia, pelargonium, iris, impatiens, cyclamen grape, apple, Euphorbia or Fuchsia or other ornamental or horticultural thereof exhibiting altered inflorescence including tissue having a purple to blue color.
[0101] In an embodiment, the plant and its progeny, further comprise genetic material encoding a non-indigenous ThMT and/or ThFNS. Plant cells may require to be transformed with two or more genetic constructs each carrying one or more of the various genes. The range “purple to blue color” includes mauve.
[0102] Cut flowers, tissue culturable cells, regenerable cells, parts of plants, seeds, reproductive material (including pollen) are all encompassed by the present invention.
[0103] As indicated above, nucleotide sequences encoding F3′5′H and DFR enzymes may all come from the same species of plant or from two or more different species. F3′5′H nucleotide sequence from Viola sp and a DFR from a Petunia sp and carnation are particularly useful in the practice of the present invention. The nucleotide sequences encoding the F3′5′H enzymes and the DFR enzymes and the respective amino acid sequences are defined in Table 1.
[0104] Nucleic acid molecules encoding F3′5′Hs are also provided in International Patent Application No. PCT/AU92/00334 and Holton et al, 1993 supra. These sequences have been used to modulate 3′,5′ hydroxylation of flavonoids in petunia (see International Patent Application No. PCT/AU92/00334 and Holton et al, 1993 supra), tobacco (see International Patent Application No. PCT/AU92/00334) and carnations (see International Patent Application No. PCT/AU96/00296). Nucleotide sequences of F3′5′H from other species such as Viola, Salvia and Sollya have been cloned (see International Patent Application No. PCT/AU03/01111). Any of these sequences may be used in combination with a promoter and/or terminator. The present invention particularly contemplates F3′5′H encoded by SEQ ID NO:1 and a DFR encoded by SEQ ID NO:3 and a carnation DFR (Z67983, gi: 1067126) (SEQ ID NO:9) or a nucleotide sequence capable of hybridizing to any of SEQ ID NOs:1 or 3 or 9 or a complementary form thereof under low or high stringency conditions or which has at least about 70% identity to SEQ ID NO:1 or 3 or 9 after optimal alignment.
[0105] For the purposes of determining the level of stringency to define nucleic acid molecules capable of hybridizing to SEQ ID NO:1, SEQ ID NO:3, SEQ ID NO:9 or their complementary forms, low stringency includes and encompasses from at least about 0% to at least about 15% v/v formamide and from at least about 1M to at least about 2 M salt for hybridization, and at least about 1 M to at least about 2 M salt for washing conditions. Generally, low stringency is from about 25-30° C. to about 42° C. The temperature may be altered and higher temperatures used to replace the inclusion of formamide and/or to give alternative stringency conditions. Alternative stringency conditions may be applied where necessary, such as medium stringency, which includes and encompasses from at least about 16% v/v to at least about 30% v/v formamide and from at least about 0.5 M to at least about 0.9 M salt for hybridization, and at least about 0.5 M to at least about 0.9 M salt for washing conditions, or high stringency, which includes and encompasses from at least about 31% v/v to at least about 50% v/v formamide and from at least about 0.01 M to at least about 0.15 M salt for hybridization, and at least about 0.01 M to at least about 0.15 M salt for washing conditions. In general, washing is carried out T m =69.3+0.41 (G+C) % (Marmur and Doty, J. Mol. Biol. 5:109, 1962). However, the T m of a duplex DNA decreases by 1° C. with every increase of 1% in the number of mismatch base pairs (Bonner and Laskey, Eur. J. Biochem. 46:83, 1974). Formamide is optional in these hybridization conditions. Particular levels of washing stringency include as follows: low stringency is 6×SSC buffer, 1.0% w/v SDS at 25-42° C.; a moderate stringency is 2×SSC buffer, 1.0% w/v SDS at a temperature in the range 20° C. to 65° C.; high stringency is 0.2 to 2×SSC buffer, 0.1%-1.0% w/v SDS at a temperature of at least 65° C.
[0106] Reference to at least 70% identity includes 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99 and 100% identity. The comparison may also be made at the level of similarity of amino acid sequences of SEQ ID NO:s:2, 4 or 10. Hence, nucleic acid molecules are contemplated herein which encode an F3′5′H enzyme or DFR having at least 70% similarity to the amino acid sequence set forth in SEQ ID NOs:2 or 4 10. Again, at least 70% similarity includes 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99 and 100% similarity or identity.
[0107] The nucleic acid molecule encoding the F3′5′H and DFR enzymes and expression of the ds cam DFR molecule includes one or more promoters and/or terminators. In one embodiment, a promoter is selected which directs expression of a F3′5′H and/or a DFR nucleotide sequence in tissue having a higher pH.
[0108] In an embodiment, the promoter sequence is native to the host carnation plant to be transformed or may be derived from an alternative source, where the region is functional in the host plant. Other sources include the Agrobacterium T-DNA genes, such as the promoters for the genes encoding enzymes for biosynthesis of nopaline, octapine, mannopine, or other opines; promoters from plants, such as promoters from genes encoding ubiquitin; tissue specific promoters (see, e.g., U.S. Pat. No. 5,459,252 to Conkling et al; WO 91/13992 to Advanced Technologies); promoters from plant viruses (including host specific viruses), or partially or wholly synthetic promoters. Numerous promoters that are potentially functional in carnation plants (see, for example, Greve, J. Mol. Appl. Genet. 1:499-511, 1983; Salomon et al, EMBO, J. 3:141-146, 1984; Garfinkel et al, Cell 27:143-153, 1983; Barker et al, Plant Mol. Biol. 2:235-350, 1983); including various promoters isolated from plants (such as the Ubi promoter from the maize obi-1 gene, see, e.g., U.S. Pat. No. 4,962,028) and viruses (such as the cauliflower mosaic virus promoter, CaMV 35S). In other embodiments the promoter is AmCHS 5′, RoseCHS 5, carnANS 5′ and/or petDFR 5′ (from Pet gen DFR) with corresponding terminators petD8 3′, nos 3, carn ANS 3′ and petDFR 3′ (from Pet gen DFR), respectively.
[0109] The promoter sequences may include cis-acting sequences which regulate transcription, where the regulation involves, for example, chemical or physical repression or induction (e.g., regulation based on metabolites, light, or other physicochemical factors; see, e.g., WO 93/06710 disclosing a nematode responsive promoter) or regulation based on cell differentiation (such as associated with leaves, roots, seed, or the like in plants; see, e.g. U.S. Pat. No. 5,459,252 disclosing a root-specific promoter).
[0110] Other cis-acting sequences which may be employed include transcriptional and/or translational enhancers. These enhancer regions are well known to persons skilled in the art, and can include the ATG initiation codon and adjacent sequences.
[0111] The nucleic acid molecule(s) encoding at least one F3′5′H enzyme and at least one DFR enzyme and incorporation of at least one ds carnDFR molecule, in combination with suitable promoters and/or a terminators is/are used to modulate the activity of a flavonoid molecule in a spray carnation. Reference herein to modulating the level of a delphinidin-based molecule relates to an elevation or reduction in levels of up to 30% or more particularly of 30-50%, or even more particularly 50-75% or still more particularly 75% or greater above or below the normal endogenous or existing levels of activity.
[0112] The term “inflorescence” as used herein refers to the flowering part of a plant or any flowering system of more than one flower which is usually separated from the vegetative parts by an extended internode, and normally comprises individual flowers, bracts and peduncles, and pedicels. As indicated above, reference to a “transgenic plant” may also be read as a “genetically modified plant” and includes a progeny or hybrid line ultimately derived from a first generation transgenic plant.
[0113] The present invention also contemplates the use of genetic sequences encoding at least one non-indigenous F3′5′H enzyme and at least one non-indigenous DFR enzyme and incorporation of at least one ds carnDFR molecule which down regulates expression of an indigenous DFR gene in the manufacture of a spray carnation such as a Cerise Westpearl carnation or sports thereof exhibiting altered inflorescence including tissue having a purple to blue color.
[0114] The present invention also contemplates the use of genetic sequences encoding at least one non-indigenous F3′5′H enzyme and at least one non-indigenous DFR enzyme and incorporation of at least one ds chrysDFR molecule which down regulates expression of an indigenous DFR gene in the manufacture of a chrysanthemum plant or sports thereof exhibiting altered inflorescence including tissue having a purple to blue color.
[0115] The present invention also contemplates the use of genetic sequences encoding at least one non-indigenous F3′5′H enzyme and at least one non-indigenous DFR enzyme and incorporation of at least one ds roseDFR molecule which down regulates expression of an indigenous DFR gene in the manufacture of a rose plant or sports thereof exhibiting altered inflorescence including tissue having a purple to blue color.
[0116] The present invention also contemplates the use of genetic sequences encoding at least one non-indigenous F3′5′H enzyme and at least one non-indigenous DFR enzyme and incorporation of at least one ds gerbDFR molecule which down regulates expression of an indigenous DFR gene in the manufacture of a gerbera plant or sports thereof exhibiting altered inflorescence including tissue having a purple to blue color.
[0117] The present invention also contemplates the use of genetic sequences encoding at least one non-indigenous F3′5′H enzyme and at least one non-indigenous DFR enzyme and incorporation of at least one ds plantDFR molecule which down regulates expression of an indigenous DFR gene in the manufacture of a plant exhibiting altered inflorescence including tissue having a purple to blue color.
[0118] In an embodiment, the plant and its progeny, further comprise genetic material encoding a non-indigenous ThMT and/or ThFNS. The genetic material may comprise a single or multiple constructs. The “purple to blue color” includes mauve.
[0119] Similar use embodiments apply to other plants as listed above.
[0120] A cultivation business model is also provided, the model comprising generating a genetically modified spray carnation plant as described herein, providing platelets, seeds, regenerable cells, tissue culturable cells or other material to a grower, generating commercial sale numbers of plants, and providing cut flowers to retailers or wholesalers.
[0121] The present invention is further described by the following non-limiting Examples. In these Examples, materials and methods as outlined below were employed:
[0122] Methods followed were as described in Sambrook et al, Molecular Cloning: A Laboratory Manual , Cold Spring Harbor Laboratories, Cold Spring Harbor, N.Y., USA, 1989 or Sambrook and Russell, Molecular Cloning: A Laboratory Manual 3 rd edition, Cold Spring Harbor Laboratories, Cold Spring Harbor, N.Y., USA, 2001 or Plant Molecular Biology Manual (2 nd edition), Gelvin and Schilperoot (eds), Kluwer Academic Publisher, The Netherlands, 1994 or Plant Molecular Biology Labfax , Croy (ed), Bios scientific Publishers, Oxford, UK, 1993.
[0123] The cloning vectors pBluescript and PCR script were obtained from Stratagene, USA. pCR72.1 was obtained from Invitrogen, USA.
[0000] E. coli Transformation
[0124] The Escherichia coli strains used were:
DH5α
[0125] supE44,Δ (lacZYA-ArgF)U169, (ø801acZΔM15), hsdR17(r k − , m k + ),
recA1, endA1, gyrA96, thi-1, relA1, deoR. (Hanahan, J. Mol. Biol. 166:557, 1983)
XL1-Blue
[0126] supE44, hsdR17(r k − , m k + ), recA1, endA1, gyrA96, thi-1, relA1,
lac − ,[F′proAB, lacI q , lacZΔM15, Tn10(tet R )] (Bullock et al, Biotechniques 5:376, 1987).
BL21-CodonPlus-RIL strain
ompT hsdS(Rb-mB-) dcm+Tet r gal endA Hte [argU ileY leuW Cam r ]M15 E. coli is derived from E. coli K12 and has the phenotype Nal s , Str s , Rif s , Thi − , Ara + , Gal + , Mtl − , F − , RecA + , Uvr + , Lon + .
[0127] Transformation of the E. coli strains was performed according to the method of Inoue et al, Gene 96:23-28, 1990.
[0000] Agrobacterium tumefaciens Strains and Transformations
[0128] The disarmed Agrobacterium tumefaciens strain used was AGL0 (Lazo et al, Bio/technology 9:963-967, 1991).
[0129] Plasmid DNA was introduced into the Agrobacterium tumefaciens strain AGL0 by adding 5 μg of plasmid DNA to 100 μL of competent AGL0 cells prepared by inoculating a 50 mL LB culture (Sambrook et al, 1989 supra) and incubation for 16 hours with shaking at 28° C. The cells were then pelleted and resuspended in 0.5 mL of 85% (v/v) 100 mM CaCl 2 /15% (v/v) glycerol. The DNA- Agrobacterium mixture was frozen by incubation in liquid N 2 for 2 minutes and then allowed to thaw by incubation at 37° C. for 5 minutes. The DNA/bacterial mix was then placed on ice for a further 10 minutes. The cells were then mixed with 1 mL of LB (Sambrook et al, 1989 supra) media and incubated with shaking for 16 hours at 28° C. Cells of A. tumefaciens carrying the plasmid were selected on LB agar plates containing appropriate antibiotics such as 50 μg/mL tetracycline or 100 μg/mL gentamycin. The confirmation of the plasmid in A. tumefaciens was done by restriction endonuclease mapping of DNA isolated from the antibiotic-resistant transformants.
DNA Ligations
[0130] DNA ligations were carried out using the Amersham Ligation Kit or Promega Ligation Kit according to procedures recommended by the manufacturer.
Isolation and Purification of DNA Fragments
[0131] Fragments were generally isolated on a 1% (w/v) agarose gel and purified using the QIAEX II Gel Extraction kit (Qiagen) or Bresaclean Kit (Bresatec, Australia) following procedures recommended by the manufacturer.
[0000] Repair of Overhanging Ends after Restriction Endonuclease Digestion
[0132] Overhanging 5′ ends were repaired using DNA polymerase I Klenow fragment according to standard protocols (Sambrook et al, 1989 supra). Overhanging 3′ ends were repaired using Bacteriophage T4 DNA polymerase according to standard protocols (Sambrook et al, 1989 supra).
[0000] Removal of Phosphoryl Groups from Nucleic Acids
[0133] Shrimp alkaline phosphatase (SAP) [USB] was typically used to remove phosphoryl groups from cloning vectors to prevent re-circularization according to the manufacturer's recommendations.
Polymerase Chain Reaction (PCR)
[0134] Unless otherwise specified, PCR conditions using plasmid DNA as template included using 2 ng of plasmid DNA, 100 ng of each primer, 2 μL, 10 mM dNTP mix, 5 μL 10×Taq DNA polymerase buffer, 0.5 μL Taq DNA Polymerase in a total volume of 50 μL. Cycling conditions comprised an initial denaturation step of 5 minutes at 94° C., followed by 35 cycles of 94° C. for 20 sec, 50° C. for 30 sec and 72° C. for 1 minute with a final treatment at 72° C. for 10 minutes before storage at 4° C.
[0135] PCRs were performed in a Perkin Elmer GeneAmp PCR System 9600.
32 P-Labeling of DNA Probes
[0136] DNA fragments (50 to 100 ng) were radioactively labeled with 50 μCi of [α- 32 P]-dCTP using a Gigaprime kit (Geneworks). Unincorporated [α- 32 P]-dCTP was removed by chromatography on Sephadex G-50 (Fine) columns or Microbiospin P-30 Tris chromatography columns (BioRad).
Plasmid Isolation
[0137] Single colonies were analyzed for inserts by inoculating LB broth (Sambrook et al, 1989 supra) with appropriate antibiotic selection (e.g. 100 μg/mL ampicillin or 10 to 50 μg/mL tetracycline etc.) and incubating the liquid culture at 37° C. (for E. coli ) or 29° C. (for A. tumefaciens ) for ˜16 hours with shaking. Plasmid DNA was purified using the alkali-lysis procedure (Sambrook et al, 1989 supra) or using The WizardPlus SV minipreps DNA purification system (Promega) or Qiagen Plasmid Mini Kit (Qiagen). Once the presence of an insert had been determined, larger amounts of plasmid DNA were prepared from 50 mL overnight cultures using the alkali-lysis procedure (Sambrook et al, 1989 supra) or QIAfilter Plasmid Midi kit (Qiagen) and following conditions recommended by the manufacturer.
DNA Sequence Analysis
[0138] DNA sequencing was performed using the PRISM (trademark) Ready Reaction Dye Primer Cycle Sequencing Kits from Applied Biosystems. The protocols supplied by the manufacturer were followed. The cycle sequencing reactions were performed using a Perkin Elmer PCR machine (GeneAmp PCR System 9600). Sequencing runs were generally performed by the Australian Genome Research Facility at the University of Queensland, St Lucia, Brisbane, Australia and at The Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia.
[0139] Sequences were analyzed using a MacVector (Trade mark) application (version 9.5.2 and earlier) [MacVector Inc, Cary, N.C., USA].
[0140] Homology searches against Genbank, SWISS-PROT and EMBL databases were performed using the FASTA and TFASTA programs (Pearson and Lipman, Proc. Natl. Acad. Sci. USA 85(8):2444-2448, 1988) or BLAST programs (Altschul et al, J. Mol. Biol. 215(3):403-410, 1990). Percentage sequence similarities were obtained using LALIGN program (Huang and Miller, Adv. Appl. Math. 12:373-381, 1991) or ClustalW program (Thompson et al, Nucleic Acids Research 22:4673-4680, 1994) within the MacVector (Trade mark) application (MacVector Inc, USA) using default settings.
[0141] Multiple sequence alignments were produced using ClustalW (Thompson et al, 1994 supra) using default settings.
Plant Transformations
[0142] Plant transformations were as described in International Patent Application No. PCT/US92/02612 incorporated herein by reference or International Patent Application No. PCT/AU96/00296 or Lu et al, Bio/Technology 9:864-868, 1991. Other methods may also be employed.
[0143] Cuttings of Dianthus caryophyllus cv. Cerise Westpearl were obtained from Propagation Australia, Queensland, Australia.
Transgenic Analysis
Color Coding
[0144] The Royal Horticultural Society's Color Charts, Third and/or Fifth edition (London, UK), 1995 and/or 2007 were used to provide a description of observed color. They provide an alternative means by which to describe the color phenotypes observed. The designated numbers, however, should be taken only as a guide to the perceived colors and should not be regarded as limiting the possible colors which may be obtained.
[0145] Carnation petals consist of 3 zones, the claw, corona and limb (Glimn-Lacy and Kaufman, Botany Illustrated, Introduction to Plants, Major Groups, Flowering Plant Families, 2 nd ed, Springer, USA, 2006). In general only the petal limb is colored with the claw being a green color and the corona a white shade (see FIG. 4 ). Reference to carnation petal/flower/inflorescence color generally relates to the color of the carnation petal limb.
Chromatographic Analysis
[0146] Thin Layer Chromatography (TLC) and High Performance Liquid Chromatography (HPLC) analysis was performed generally as described in Brugliera et al, Plant J. 5:81-92, 1994.
[0147] In general TLC and HPLC analysis was performed on extracts isolated from the petal limbs.
Extraction of Anthocyanidins
[0148] Prior to HPLC analysis, the anthocyanin and flavonol molecules present in petal limb extracts were acid hydrolyzed to remove glycosyl moieties from the anthocyanidin or flavonol core. Anthocyanidin and flavonol standards were used to help identify the compounds present in the floral extracts.
[0149] Petal extracts were prepared essentially as described in Fukui et al, 2003 supra. Petal were added to 6 N HCl (0.2 mL) and boiled at 100° C. for 20 min. The hydrolyzed anthocyanidins were extracted with 0.2 mL of 1-pentanol. HPLC analysis of the anthocyanidins was performed using an ODS-A312 (15 cm×6 mm, YMC Co., Ltd, Kyoto, Japan) column, a flow rate of solvent of 1 mL min −1 , and detection at an absorbance of 600-400 nm on a SPD-M20A photodiode array detector (Shimadzu Co., Ltd). The solvent system used was as follows: acetic acid:methanol:water=15:20:65. Under these HPLC conditions, the retention time and λ max of delphinidin were 4.0 min and 534 nm, respectively, and these values were compared with those of authentic delphinidin chloride (Funakoshi Co., Ltd, Tokyo, Japan).
[0150] The anthocyanidin peaks were identified by reference to known standards, viz delphinidin, petunidin, malvidin, cyanidin and peonidin
Stages of Flower Development
[0151] Carnation flowers were harvested at developmental stages defined as follows:
[0000] Stage 1: Closed bud, petals not visible.
Stage 2: Flower buds opening: tips of petals visible.
Stage 3: Tips of nearly all petals exposed. “Paint-brush stage”.
Stage 4: Outer petals at 45° angle to stem.
Stage 5: Flower fully open.
[0152] For TLC or HPLC analysis, petal limbs were collected from stage 4 flowers at the stage of maximum pigment accumulation.
[0153] For Northern blot analysis, petals were collected from stage 3 flowers at the stage of maximal expression of flavonoid pathway genes.
Example 1
Preparation of Chimeric F3′5′H Gene Constructs
[0154] A summary of promoter, terminator and coding fragments used in the preparation of constructs and the respective abbreviations is listed in Table 2.
[0000]
TABLE 2
Abbreviations used in construct preparations
ABBREVIATION
DESCRIPTION
CaMV 35S
~0.4 kb fragment containing the promoter region from
the Cauliflower Mosaic Virus 35S (CaMV 35S) gene -
(Franck et al, I 21: 285-294, 1980, Guilley et al,
Cell , 30: 763-773. 1982)
35S 5′
promoter fragment from CaMV 35S gene (Franck et
al, 1980 supra) with an ~60 bp 5′ untranslated leader
sequence (CabL) from the petunia chlorophyll a/b
binding protein gene (Cab 22 gene) [Harpster et al,
MGG , 212: 182-190, 1988]
AmCHS 5′
Promoter fragment from the Antirrhinum majus
chalcone synthase (CHS) gene which includes 1.2 kb
sequence 5′ of the translation initiation site (Sommer
and Saedler, Mol Gen. Gent ., 202: 429-434, 1986)
BPF3′5′H#40
Viola (Black Pansy) F3′5′H cDNA clone #40
(International Patent Application No. PCT/AU03/
01111 incorporated herein by reference)
(SEQ ID NO: 1)
35S 3′
~0.2 kb terminator fragment from CaMV 35S gene
(Franck et al, 1980 supra)
Pet gen DFR
~5.3 kb Petunia DFR-A genomic clone with it's own
promoter and terminator (SEQ ID NO: 3)
petD8 3′
~0.7 kb terminator region from a phospholipid transfer
protein gene (D8) of Petunia hybrida cv. OGB includes
a 150 bp untranslated region of the transcribed region
of PLTP gene (Holton, Isolation and characterization of
petal-specific genes from Petunia hybrida . PhD Thesis,
University of Melbourne, 1992)
SuRB
Herbicide (Chlorsulfuron)-resistance gene (encodes
Acetolactate Synthase) with its own terminator (tSuRB)
from Nicotiana tabacum (Lee et al, EMBO J . 7: 1241-
1248, 1988)
ds carnDFR
“double stranded (ds) carnation DFR” fragment
harboring a ~0.3 kb sense partial carnation DFR cDNA
fragment: 180 bp petunia DFR-A intron 1 fragment
(Beld et al, 1989 supra): ~0.3 kb anti-sense partial
carnation DFR fragment with the aim of formation of
double stranded (hairpin loop) RNA molecule to induce
RNAi-mediated silencing of the endogenous carnation
DFR. The sequence of a complete carnation DFR clone
(Z67983, gi: 1067126) is shown in SEQ ID NO: 9.
ThMT
~1.0 kb cDNA clone corresponding to
S-adenosylmethionine: anthocyanin 3′ 5′
methyltransferase from torenia (International Patent
Application No. PCT/AU03/00079 incorporated
herein by reference) (SEQ ID NO: 11)
ThFNS
~1.7 kb cDNA clone corresponding to flavone synthase
from torenia (Akashi et al., Plant Cell Physiol . 40 (11):
1182-1186, 1999, International Patent Application No.
PCT/JP00/00490 incorporated herein by reference)
(SEQ ID NO: 13)
carnANS 5′
Promoter sequence of anthocyanidin synthase (ANS)
gene from Dianthus caryophyllus (See International
Patent Application No. PCT/GB99/02676 incorporated
herein by reference) (SEQ ID NO: 15)
carnANS 3′
Terminator sequence of anthocyanidin synthase gene
(ANS) from Dianthus caryophyllus (See International
Patent Application No. PCT/GB99/02676 incorporated
herein by reference) (SEQ ID NO: 16)
RoseCHS 5′
~2.8 kb fragment containing the promoter region from
a CHS gene of Rosa hybrida (see International Patent
Application No. PCT/AU03/01111 incorporated herein
by reference) (SEQ ID NO: 17)
e35S 5′
~0.7 kb fragment incorporating an enhanced CaMV
35S promoter (Mitsuhashi et al. Plant Cell Physiol .
37: 49-59, 1996)
[0155] Cerise Westpearl is a cerise colored carnation (RHSCC 57D) It typically accumulates pelargonidin-based pigments (˜99% of total anthocyanin content of 1.0 mg/g petal fresh weight) and therefore lacks F3′H activity and so is presumed mutant in the F3′H gene. HPLC analysis results on 2 flowers revealed 1.08 mg/g anthocyanin (99% pelargonidin), 2.9 to 4.6 mg/g flavonols and 0.3 to 0.6 mg/g dihydroflavonols accumulating in the petals of Cerise Westpearl. Cerise Westpearl is a sport of the pink colored flower Westpearl.
[0156] In order to produce novel purple/blue flowers in the spray carnation background of Cerise Westpearl, two binary vector constructs were prepared utilizing the pansy F3′5′H cDNA clone and petunia genomic DFR gene with or without a ds carnDFR expression cassette.
[0157] Table 3 provides a summary of chimeric F3′5′H and DFR gene expression cassettes contained in binary vector constructs used in the transformation of Cerise Westpearl (see Table 2 for an explanation of abbreviations).
[0000] TABLE 3 Summary of Chimeric Constructs Construct ds plantDFR DFR F3′5′H Other pCGP3360 none Pet gen DFR AmCHS 5′: BPF3′5′H#40: petD8 3′ pCGP3366 CaMV35S: Pet gen DFR AmCHS 5′: ds carn DFR: BPF3′5′H#40: 35S 3′ petD8 3′ pCGP3601 CaMV35S: Pet gen DFR AmCHS 5′: carnANS 5′: ds carn DFR: BPF3′5′H#40: ThMT: 35S 3′ petD8 3′ carnANS 3′ pCGP3605 CaMV35S : Pet gen DFR AmCHS5′: CaMV 35S: ds carn DFR: BPF3′5′H#40: ThMT: 35S 3′ petD8 3′ 35S 3′ pCGP3616 CaMV35S: Pet gen DFR AmCHS 5′: RoseCHS 5′: ds carn DFR: BPF3′5′H#40: ThFNS: 35S 3′ petD8 3′ nos 3′ pCGP3607 CaMV35S: Pet gen DFR AmCHS 5′: e35S 5′: ds carn DFR: BPF3′5′H#40: ThFNS: 35S 3′ petD8 3′ petD8 3′
NB All have ALS selectable marker gene (35S 5′:SuRB)
Refer to Table 2 for a description of abbreviations and genetic elements.
[0158] The constructs pCGP3601, 3605, 3607, 3616 are all based upon pCGP3366 and have an extra expression cassette that is either a floral specific or constitutive expression of anthocyanin 3′S′ methyltransferase cDNA clone from torenia (targeting methylating of the delphinidin) [pCGP3601 and 3605] or floral specific or constitutive expression of a flavone synthase cDNA clone from torenia (targeting producing of the co-pigments, flavones) [pCGP3616 and 3607].
Preparation of the Constructs
[0159] The Transformation Vector pCGP3360 (AmCHS 5′:BPF3′5′H#40:petD8 3′; Pet gen DFR; 35S 5′:SuRB)
[0160] The transformation vector pCGP3360 contains the AmCHS 5′:BPF3′5′H#40: petD8 3′ expression cassette and the petunia genomic DFR-A gene along with the 35S 5′: SuRB selectable marker gene.
[0000] Construction of the Intermediate Plasmid, pCGP3356 (AmCHS 5′:BPF3′5′H#40:pet D8 3)
[0161] The plasmid pCGP3356 contains a chimeric gene consisting of AmCHS 5′: BPF3′5′H#40:petD8 3′ in a pBluescript backbone.
[0162] A ˜1.6 kb fragment harboring the BPF3′5′H#40 cDNA clone was released from the plasmid pCGP1961 (see International Patent Application No. PCT/AU03/01111) upon digestion with the restriction endonucleases EcoRI and KpnI. The overhanging ends were repaired and the fragment was purified. The plasmid pCGP725 containing AmCHS 5′: petHf1:petD8 3′ in pBluescript (described in International Patent Application No. PCT/AU03/01111) was digested with the restriction endonucleases XbaI and BamHI to release the backbone vector harboring the AmCHS 5′ and petD8 3′ regions. The overhanging ends were repaired and the ˜4.9 kb fragment was isolated, purified and ligated with the blunt ended BPF3′5′H#40 fragment from pCGP1961 (described above). Correct insertion of the BPF3′5′H#40 cDNA clone in a sense orientation between the Am CHS 5′ promoter and the pet D8 3′ terminator was established by restriction endonuclease analysis of plasmid DNA isolated from ampicillin-resistant transformants. The resulting plasmid was designated as pCGP3356.
[0000] Construction of the Intermediate Plasmid, pCGP3357 (AmCHS 5′:BPF3′5′H#40:pet D8 3′ in pCGP1988)
[0163] The plasmid pCGP3357 contains a chimeric gene consisting of AmCHS 5′:
[0164] BPF3′5′H#40:petD8 3′ along with the 35S 5′:SuRB selectable marker gene in the pCGP1988 vector (see International Patent Application No. PCT/AU03/01111).
[0165] The plasmid pCGP3356 (described above) was digested with the restriction endonuclease PstI to release a 3.5 kb fragment bearing the AmCHS 5′:BPF3′5′H#40: petD8 3′ expression cassette. The resulting 5′-overhang was repaired using DNA Polymerase I (Klenow fragment) according to standard protocols (Sambrook et al, 1989 supra). The fragment was purified and ligated with SmaI ends of the plasmid pCGP1988 (see International Patent Application No. PCT/AU03/01111). Correct insertion of AmCHS 5′:BPF3′5′H#40:petD8 3′ gene in a tandem orientation with respect to the 35S 5′:SuRB selectable marker gene cassette was established by restriction endonuclease analysis of plasmid DNA isolated from tetracycline-resistant transformants. The resulting plasmid was designated as pCGP3357.
[0000] Construction of the Intermediate Plasmid, pCGP1472 (Petunia DFR-A Genomic Clone)
[0166] A genomic library was made from Petunia hybrida cv. Old Glory Blue DNA in the vector λ2001 (Holton, 1992 supra). Approximately 200,000 pfu were plated out on NZY plates, lifts were taken onto NEN filters and the filters were hybridized with 400,000 cpm/mL of 32 P-labeled petunia DFR-A cDNA fragment (described in Brugliera et al, 1994, supra). Hybridizing clones were purified, DNA was isolated from each and mapped by restriction endonuclease digestion. A 13 kb Sad fragment of one of these clones was isolated and ligated with Sad ends of pBluescriptII to create the plasmid pCGP1472. Finer mapping indicated that an ˜5.3 kb BglII fragment contained the entire petunia DFR-A gene (Beld et al, 1989 supra).
[0000] Construction of the Transformation Vector, pCGP3360
[0167] The 5.3 kb fragment harboring the pet gen DFR gene was released from the plasmid pCGP1472 upon digestion with the restriction endonuclease BglII. The overhanging ends were repaired and the fragment was purified and ligated with the repaired AscI ends of the plasmid pCGP3357 (described above). Correct insertion of pet gen DFR gene in a tandem orientation with respect to the AmCHS BPF3′5′H#40:petD8 3′ and 35S 5′:SuRB genes was established by restriction endonuclease analysis of plasmid DNA isolated from tetracycline-resistant transformants. The resulting plasmid was designated as pCGP3360 ( FIG. 2 ).
[0000] The Transformation Vector pCGP3366 (CaMV35S:ds carn DFR:35S 3′; Pet gen DFR; AmCHS 5′:BPF3′5′H#40:petD8 3; 35S 5′:SuRB)
[0168] The transformation vector pCGP3366 contains the AmCHS 5′:BPF3′5′H#40: petD8 3′ expression cassette and the petunia genomic DFR-A (pet gen DFR) genes along with a CaMV35S:ds carn DFR:35S 3′ expression cassette and the 35S 5′:SuRB selectable marker gene.
[0000] Construction of the Intermediate Plasmid pCGP3359
[0169] A fragment bearing 180 bp of the petunia DFR-A intron 1 was amplified by PCR using the plasmid pCGP1472 (described above) as template and the following primers:
[0000]
DFRint35S F
(SEQ ID NO: 5)
GCAT CTCGAG GGATCC TCG TGA TCC TGG TAT GTT TTG
XhoI BamHI
DFRint35S R
(SEQ ID NO: 6)
GCAT TCTAGA AGATCT CTT CTT GTT CTC TAC AAA ATC
BglII BamHI
[0170] The forward primer (DFRint35S F) was designed to incorporate the restriction endonuclease recognition sites XhoI and BamHI at the 5′-end. The reverse primer (DFRint35S R) was designed to incorporate Xba I and BglII restriction endonuclease recognition sites at the 3′-end of the 180 bp product that was amplified. The resulting 180 by PCR product was then digested with the restriction endonucleases XhoI and XbaI and ligated with XhoI/XbaI ends of the plasmid pRTppoptcAFP (a source of the CaMV35S promoter and terminator fragments) (Wnendt et al., Curr Genet. 25: 510-523, 1994). Correct insertion of the petunia DFR-A intron 1 fragment between the CaMV35S and 35S 3′ fragments of pRTppoptcAFP was confirmed by restriction endonuclease analysis of plasmid DNA isolated from ampicillin-resistant transformants. The resulting plasmid was designated pCGP3359.
[0000] Isolation of Full-Length Carnation DFR cDNA Clone
[0171] Isolation of a partial carnation DFR cDNA clone has been described in International Patent Application No. PCT/AU96/00296.
[0172] Around 120,000 pfus of a carnation Kortina Chanel petal cDNA library (construction of which is described in International Patent Application No. PCT/AU97/000124) were screened using the 32 P-labeled fragments of an EcoRI/XhoI partial carnation DFR fragment (see International PCT/AU96/00296) as a probe under high stringency hybridization washing conditions. Around 20 strongly hybridizing plaques were selected and further purified. Of these one (KCDFR#17) contained a 1.3 kb insert and represented a full-length carnation DFR cDNA clone with 51 bp of 5′ untranslated sequence. The plasmid was designated as pCGP1547.
[0000] Construction of the Intermediate Plasmid pCGP3363 (CaMV35S: Sense Partial Carnation DFR: Petunia DFR Intron 1:35S 3)
[0173] A fragment bearing ˜300 bp of the carnation DFR cDNA clone was amplified by PCR using the plasmid pCGP1547 (described above) as template and the following primers:
[0000]
ds carnDFR F
(SEQ ID NO: 7)
GCAT TCTAGA CTCGAG CGA GAA TGA GAT GAT AAA ACC
Xbal Xhol
ds carnDFR R
(SEQ ID NO: 8)
GCAT AGATCT GGATCC GAG ATT GTT TTC TGC TGC G
BglII BamHI
[0174] The forward primer (ds carnDFR F) was designed to incorporate the restriction endonuclease recognition sites XbaI and XhoI at the 5′-end. The reverse primer (ds carnDFR R) was designed to incorporate BglII and BamHI restriction endonuclease recognition sites at the 3′-end of the ˜300 bp product that was amplified. The resulting ˜300 bp PCR product was then digested with the restriction endonucleases XhoI and BamHI and ligated with XhoI/BamHI ends of the plasmid pCGP3359 (described above). Correct insertion of the partial carnation DFR fragment in a sense direction between the CaMV35S and petunia DFR intron 1 fragment of the plasmid pCGP3359 was confirmed by restriction endonuclease analysis of plasmid DNA isolated from ampicillin-resistant transformants. The resulting plasmid was designated pCGP3363.
[0000] Construction of the Intermediate Plasmid pCGP3364 (CaMV35S:ds Carn DFR:35S 39
[0175] The amplified partial carnation DFR fragment described above was digested with the restriction endonucleases BglII and XbaI and ligated with BglII/XbaI ends of the plasmid pCGP3363 (described above). Correct insertion of the partial carnation DFR fragment in an anti-sense direction between the petunia DFR intron 1 and 35S 3′ fragments of the plasmid pCGP3363 was confirmed by restriction endonuclease analysis of plasmid DNA isolated from ampicillin-resistant transformants. The resulting plasmid was designated pCGP3364.
[0000] Construction of the Transformation Vector, pCGP3366
[0176] A ˜1.4 kb fragment bearing the CaMV35S:ds carn DFR:35S 3′ expression cassette was released from the plasmid pCGP3364 (described above) upon digestion with the restriction endonuclease PstI. The fragment was purified and ligated with the PstI ends of the plasmid pCGP3360 (described above) ( FIG. 2 ). Correct insertion of CaMV35S:ds carn DFR:35S 3′ expression cassette in a tandem orientation with respect to the AmCHS 5′:BPF3′5′H#40:petD8 3; pet gen DFR and 35S 5′:SuRB genes was established by restriction endonuclease analysis of plasmid DNA isolated from tetracycline-resistant transformants. The resulting plasmid was designated as pCGP3366 ( FIG. 3 ).
[0177] The T-DNAs of the transformation vectors pCGP3360 and pCGP3366 were introduced into the spray carnation line, Cerise Westpearl via Agrobacterium -mediated transformation. Transgenic cells were selected based on their ability to grow and produce roots on media containing the herbicide, chlorsulfuron. Transgenic plantlets with roots were removed form media and transferred to soil and grown to flowering in temperature controlled greenhouses in Bundoora, Victoria, Australia.
[0178] The color of the petal limbs of the transgenic plants were recorded by eye using RHSCC and HPLC analysis was used to determine the anthocyanidins in the hydrolyzed petal limb extracts. The results are summarized in Table 4.
[0000]
TABLE 4
Results of transgenic analysis of petals from Cerise Westpearl carnations transformed
with T-DNAs containing F3′5′H and DFR gene expression cassettes.
#
% del
Del
transgenes
pCGP
#tg
% CC
HPLC
(Range)
Av del
mg/g FW
AmCHS 5′: BP F3′5′H #40: petD8
3360
38
57%
13
52 to 76%
65%
0.42 to 1.98
3′;
Pet gen DFR
AmCHS 5′: BP F3′5′H #40: petD8
3366
47
94%
34
51 to 93%
84%
0.28 to 2.68
3′;
Pet gen DFR;
CaMV 35S: ds carnDFR: 35S 3′
Transgenes = chimeric F3′5′H and DFR nucleotide sequences contained on the T-DNA
pCGP = plasmid pCGP identification number of the transformation vector used in the transformation experiment (refer to Table 3 for details)
#tg = total number of transgenic carnation lines produced
% CC = the percentage of the total number of events produced that had a shift in petal color towards the purple range
# HPLC = number of individual events of which the anthocyanidins of hydrolyzed petal limb extracts were analyzed by HPLC. Petals for analysis were selected based on a visible shift in color of the petal from pink into the purple range.
% del (range) = the range in % of delphinidin detected in the hydrolyzed extracts of the petals for the population of transgenic events
Av del = the average % of delphinidin detected in the hydrolyzed extracts of the petals for the population of transgenic events
Del mg/g FW = the range in the amount of delphinidin (in mg/g of fresh weight) detected in the hydrolyzed extracts of the petals for the population of transgenic events
[0179] The results suggest that of the two constructs tested (pCGP3360 and pCGP3366), pCGP3366 resulted in a higher percentage of events that produced flowers with a shift in color to the purple range. Furthermore the average delphinidin detected in the hydrolyzed extracts of the petals was higher in pCGP3366 events compared to pCGP3360 events. This was presumably due to the down regulation of the endogenous carnation DFR by the ds carnDFR cassette via RNAi-mediated silencing leading to decreased competition between the endogenous DFR and the introduced F3′5′H for the DHK substrate. The introduced petunia DFR (which is not able to utilise DHK) subsequently allowed conversion DHM (product of F3′5′H reaction on DHK) to leucodelphinidin and activity by the endogenous anthocyanin pathway enzymes resulted in delphinidin derived pigments accumulating in the petal tissue. To identify spray carnation lines producing petals of a novel color, the colors of petal limbs were compared to mauve/purple carnation lines already in the market place. These included the midi carnation lines FLORIGENE Moonshadow (Trade mark) [82A, 82B] and FLORIGENE Moondust (76A) and the standard carnation lines FLORIGENE Moonvista (Trade mark) [81A+], FLORIGENE Moonshade (Trade mark) [81A, 82A], FLORIGENE Moonlite (Trade mark) [77D/82D, 77C, N80B] and FLORIGENE Moonaqua (Trade mark) [84A/B]. Twenty two CW/3366 lines were initially selected as being novel spray carnation lines whilst only one CW/3360 line was selected as being novel spray carnation line. Further trailing with respect to petal color consistency and petal number reduced the list to 11 CW/3366 lines and no CW/3360 lines as being novel spray carnation lines with potential for new product lines (Table 5).
[0000]
TABLE 5
RHS color code of the petal limb and delphinidin levels detected in
selected Cerise Westpearl/3366 lines
ACCESSION
RHSCC
Delphinidin levels
NUMBER
NUMBER
%, (mg/g FW)
25930
77A
92%
(2.2 mg/g)
25931
77A+
93%
(1.7 mg/g)
25932
77A+
93%
(2.3 mg/g)
25946
81B/82B
84%
(0.3 mg/g)
25947
77D, 78D
nd
25958
81B, 82A, N80B
81%
(0.5 mg/g)
25961
77B, 88D
nd
25965
82A
85%
(0.7 mg/g)
25966
81B, 82A
83%
(0.4 mg/g)
25973
82b
84%
(0.5 mg/g)
25976
81B
84%
(0.3 mg/g)
FLORIGENE Moondust
76A
100%
(0.035 mg/g)
FLORIGENE Moonshadow
82A, 82B
94%
(0.35 mg/g)
FLORIGENE Moonshade
81A, 82A
97%
(0.6 mg/g)
FLORIGENE Moonlite
77D/82D, 77C
71%
(0.06 mg/g)
FLORIGENE Moonaqua
84A/B
74%
(0.07 mg/g)
FLORIGENE Moonvista
81A+
98%
(1.8 mg/g)
Accession number = unique number given to individual transgenic event
RHSCC number = The color code of the petal limbs from the flowers of transgenic carnation lines. “+” alongside an RHSCC number highlights that the color is a darker or more intense shade of the selected code
delphinidin levels = delphinidin levels detected in hydrolyzed extracts of petal limb tissue as determined by HPLC given in percentage of total anthocyanidins and mg/g of fresh weight of petal tissue.
nd = not done
[0180] Further field trial assessments in Colombia revealed that lines #25958, #25947, #25973, #25965 and #25976 produced novel spray carnation flower colors with consistent and stable colors and good plant growth characteristics. Two lines (#25958 and #25947) were selected for commercialization. Line #25958 was subsequently named FLORIGENE Moonberry (Trade mark) and line #25947 was called FLORIGENE Moonpearl (Trade mark). Both are being grown in Colombia for production of cut flowers to markets around the world.
[0000] Introduction of the Transformation Vector pCGP3366 into Other Carnation Varieties
[0181] Due to the success in obtaining high delphinidin levels in the carnation variety, Cerise
[0182] Westpearl using the construct pCGP3366 (containing at least one F3′5′H enzyme and at least one DFR enzyme and incorporation of at least one ds carnDFR molecule) the same genes are introduced into other colored carnation cultivars such as but not limited to Cinderella, Westpearl, Vega, Artisan, Barbara, Dark Rendezvous, Miledy, Kortina Chanel.
[0183] The transgenic plants are assessed for flower color as described above and lines with novel flower color (as compared to controls) are selected for commercialization.
[0000] Use of the Binary Vector pCGP3366 as a Backbone-Addition of Other Expression Cassettes.
[0184] In order to shift petal color further towards the blue/purple spectrum other genes that modulated anthocyanin or flavonoid composition were added to the pCGP3366 binary vector. These included genes coding for S-adenosylmethionine: anthocyanin 3′5′ methyltransferase (AMT) activity to modulate the production of methylated anthocyanins such as the production of malvidin and petunidin pigments and genes coding for flavone synthase (FNS) activity to modulate the production of flavones in carnation.
[0000] Addition of AMT Expression Cassettes to the pCGP3366 Binary Construct
[0185] In an attempt to produce anthocyanins based upon malvidin (the methylated form of delphinidin) 2 new transformation vectors, pCGP3601 and pCGP3605, were prepared by addition of AMT expression cassettes to the transformation vector, pCGP3366 ( FIG. 3 ). The AMT sequence from torenia (International Patent Application No. PCT/AU03/00079) was used under the control of a floral specific promoter fragment from the ANS gene of carnation (carnANS 5′) and a constitutive promoter fragment from the cauliflower mosaic virus 35S gene (CaMV35S).
[0000] The Transformation Vector, pCGP3601 (carnANS 5′:ThMT:carnANS 3; AmCHS 5′: BPF3′5′H#40:petD8 3′; Pet gen DFR; CaMV35S 5′:ds carn DFR:35S 3; 35S 5′: SuRB)
[0186] The binary construct pCGP3601 contains a carnANS 5′:ThMT:carnANS 3′ expression cassette in the pCGP3366 binary construct backbone (described above) ( FIG. 3 ).
[0000] Construction of the Intermediate Plasmid, pCGP3431 (carnANS 5′:ThMT:carnANS 3)
[0187] A ˜1.0 kb fragment bearing the torenia AMT cDNA clone (ThMT) (SEQ ID NO: 11) was released from the plasmid pTMT5 (described in International Patent Application No.: PCT/JP00/00490) upon digestion with the restriction endonucleases EcoRI and Asp718. The overhanging ends were repaired and the purified fragment was ligated with XbaI/PstI repaired ends of the plasmid pCGP1275 (described in International Patent Application No. PCT/AU2008/001700 incorporated herein by reference). Correct insertion of the ThMT fragment in between a promoter fragment of the carnation ANS gene (carnANS 5) and a terminator fragment of the carnation ANS gene (carnANS 3) was established by restriction endonuclease analysis of plasmid DNA isolated from ampicillin resistant transformants. The resulting plasmid was designated as pCGP3431.
[0000] Construction of the Transformation Vector, pCGP3601
[0188] A 4.4 kb fragment harboring the carnANS 5′:ThMT:carnANS 3′ expression cassette was isolated from the plasmid pCGP3431 (described above) upon digestion with the restriction endonuclease ClaI. The overhanging ends were repaired and the purified fragment was ligated with the PmeI ends of the plasmid pCGP3366 (described above) ( FIG. 3 ). Correct insertion of the carnANS 5′:ThMT:carnANS 3′ expression cassette in a tandem orientation with respect to the AmCHS 5′:BPF3′5′H#40:petD8 3, pet gen DFR; CaMV35S 5′:ds carn DFR:35S 3′ and 35S 5′:SuRB genes was established by restriction endonuclease analysis of plasmid DNA isolated from tetracycline-resistant transformants. The resulting plasmid was designated as pCGP3601 ( FIG. 4 ).
[0000] The Transformation Vector, pCGP3605 (CaMV35S:ds cam DFR:35S 3; CaMV35S: ThMT:35S 3; Pet gen DFR; AmCHS 5′:BPF3′5′H#40:petD8 3; 35S 5′:SuRB)
[0189] The binary construct pCGP3605 contains a CaMV35S:ThMT:35S 3′ expression cassette in the pCGP3366 binary construct backbone (described above) ( FIG. 3 ).
[0000] Construction of the Intermediate Plasmid, pCGP3097 (CaMV35S:ThMT:35S 3)
[0190] The plasmid pTMT5 (described in International Patent Application No. PCT/JP00/00490) was firstly linearized upon digestion with the restriction endonuclease Asp718. The overhanging ends were repaired and a ˜1.0 kb fragment bearing the torenia AMT cDNA clone (ThMT) (SEQ ID NO: 11) was then released from the linearized plasmid upon digestion with the restriction endonuclease EcoRI. The fragment was purified and ligated with XbaI (repaired ends)/EcoRI ends of the plasmid pRTppoptcAFP (a source of the CaMV35S promoter and terminator fragments) (Wnendt et al., 1994, supra). Correct insertion of the ThMT fragment in a sense orientation between the promoter and terminator fragments of the cauliflower mosaic virus 35S gene (CaMV35S and 35S 3′ respectively) was established by restriction endonuclease analysis of plasmid DNA isolated from ampicillin resistant transformants. The resulting plasmid was designated as pCGP3097.
[0000] Construction of the Transformation Vector, pCGP3605
[0191] A ˜1.6 kb fragment harboring the CaMV35S:ThMT: 35S 3′ expression cassette was isolated from the plasmid pCGP3097 (described above) upon digestion with the restriction endonuclease PstI. The overhanging ends were repaired and the purified fragment was ligated with the PmeI ends of the plasmid pCGP3366 (described above) ( FIG. 3 ). Correct insertion of the CaMV35S:ThMT:35S 3′ expression cassette in a tandem orientation with respect to the AmCHS 5′:BPF3′5′H#40:petD8 3, pet gen DFR; CaMV35S:ds carn DFR:35S 3′ and 35S 5′:SuRB genes was established by restriction endonuclease analysis of plasmid DNA isolated from tetracycline-resistant transformants. The resulting plasmid was designated as pCGP3605 ( FIG. 5 ).
[0000] Addition of FNS Expression Cassettes to the pCGP3366 Binary Construct
[0192] In an attempt to produce flavones (to act as co-pigments) and high levels of delphinidin in a Cerise Westpearl background, a further 2 transformation vectors, pCGP3616 and pCGP3607 were prepared by adding FNS expression cassettes to the transformation vector, pCGP3366 ( FIG. 3 ). The FNS sequence from torenia (International Patent Application No. PCT/JP00/00490) (SEQ ID NO: 13) was used under the control of a floral specific promoter fragment from the CHS gene of rose (RoseCHS 5) and a constitutive promoter fragment from the cauliflower mosaic virus 35S gene (CaMV35S).
[0000] The Transformation Vector, pCGP3616 (CaMV35S:ds carn DFR:35S 3; RoseCHS 5′: ThFNS:nos 3; Pet gen DFR; AmCHS 5′:BPF3′5′H#40:petD8 3; 35S 5′:SuRB)
[0193] The binary construct pCGP3616 contains a RoseCHS 5′:ThFNS:nos 3′ expression cassette in the pCGP3366 binary construct backbone (described above) ( FIG. 3 ).
[0000] Construction of the Intermediate Plasmid, pCGP3123 (RoseCHS 5′:ThFNS:nos 3)
[0194] A 3.2 kb fragment bearing e35S 5′:ThFNS:petD8 3′ expression cassette was released from the binary vector plasmid pSFL535 (described in International Patent Application WO2008/156206) upon digestion with the restriction endonuclease AscI. The fragment was purified and ligated with the AscI ends of the 2.9 kb plasmid pUCAP+AscI (The plasmid pUCAP/AscI is a pUC19 based cloning vector with extra cloning sites specifically an AscI recognition site at either ends of the multicloning site). Correct insertion of the e35S 5′: ThFNS:petD8 3′ expression cassette in the pUC based cloning vector was established by restriction endonuclease analysis of plasmid DNA isolated from ampicillin resistant transformants. The resulting plasmid was designated as pCGP3123.
[0000] Construction of the Intermediate Plasmid, pCGP3612 (RoseCHS 5′:ThFNS:nos 3)
[0195] This plasmid pCGP3123 (described above) was linearized upon digestion with the restriction endonuclease BamHI. The overhanging ends were repaired and a fragment bearing the ThFNS cDNA clone was then released after partial digestion of the linearized plasmid with the restriction endonuclease XhoI. The 1.7 kb fragment was purified and ligated with SmaI/XhoI ends of the plasmid pCGP2203 (Rose CHS 5′:BPF3′5′H#18:nos 3′ in pBluescript backbone) described in International Patent Application No. PCT/AU2008/001694. Correct insertion of the ThFNS fragment between the RoseCHS promoter and nos terminator was established by restriction endonuclease analysis of plasmid DNA isolated from ampicillin resistant transformants. The resulting plasmid was designated pCGP3612.
[0000] Construction of the Transformation Vector, pCGP3616
[0196] A 4.9 kb fragment harboring the RoseCHS 5′:ThFNS:nos 3′ expression cassette was isolated from the plasmid pCGP3612 (described above) upon digestion with the restriction endonucleases BglII and NotI. The overhanging ends were repaired and the purified fragment was ligated with the PmeI ends of the plasmid pCGP3366 (described above) ( FIG. 3 ). Correct insertion of the RoseCHS 5′:ThFNS:nos 3′ expression cassette in a tandem orientation with respect to the AmCHS 5′:BPF3′5′H#40:petD8 3, pet gen DFR; CaMV35S:ds carn DFR:35S 3′ and 35S 5′:SuRB genes was established by restriction endonuclease analysis of plasmid DNA isolated from tetracycline-resistant transformants. The resulting plasmid was designated as pCGP3616 ( FIG. 6 ).
[0000] The Transformation Vector, pCGP3607 (CaMV35S′:ds carn DFR:35S 3; e35S 5′: ThFNS:petD8 3; Pet gen DFR; AmCHS 5′:BPF3′5′H#40:petD8 3; 35S 5′:SuRB)
[0197] The binary construct pCGP3607 contains an e35S 5′:ThFNS:petD8 3′ expression cassette in the pCGP3366 binary construct backbone (described above) ( FIG. 3 ).
[0000] Construction of the Transformation Vector, pCGP3607
[0198] A 3.2 kb fragment bearing e35S 5′:ThFNS:petD8 3′ expression cassette was released from the plasmid pCGP3123 (described above) upon digestion with the restriction endonuclease AscI. The fragment was purified and ligated with the PmeI ends of the plasmid pCGP3366 (described above) ( FIG. 3 ). Correct insertion of the e35S 5′:ThFNS:petD8 3′ expression cassette in a tandem orientation with respect to the AmCHS 5′:BPF3′5′H#40: petD8 3, pet gen DFR; CaMV35S:ds carn DFR:35S 3′ and 35S 5′:SuRB genes was established by restriction endonuclease analysis of plasmid DNA isolated from tetracycline-resistant transformants. The resulting plasmid was designated as pCGP3607 ( FIG. 7 ).
[0199] The T-DNAs of the transformation vectors pCGP3601 ( FIG. 4 ), pCGP3605 ( FIG. 5 ), pCGP3607 ( FIG. 7 ) and pCGP3616 ( FIG. 6 ) were introduced into the spray carnation line, Cerise Westpearl via Agrobacterium -mediated transformation. Transgenic cells were selected based on their ability to grow and produce roots on media containing the herbicide, chlorsulfuron. Transgenic plantlets with roots were removed form media and transferred to soil and grown to flowering in temperature controlled greenhouses in Bundoora, Victoria, Australia. The results are summarized in Table 6.
[0000]
TABLE 6
A summary of the number of transgenic Cerise Westpearl that resulted
in a significant shift in petal color towards the purple/violet range.
Construct
Addition to pCGP3366
#Tg
CC
pCGP3601
carnANS 5′: ThMT: carnANS 3′
32
11
pCGP3605
CaMV35S: ThMT: 35S 3′
38
14
pCGP3607
e35S 5′: ThFNS: petD8 3′
37
15
pCGP3616
RoseCHS 5′: ThFNS: nos 3′
19
2
Construct = plasmid pCGP identification number of the transformation vector used in the transformation experiment
Addition to pCGP3366 = Extra expression cassette added to the pCGP3366 (FIG. 3) backbone containing AmCHS 5′: BP F3′5′H #40: petD8 3′; Pet gen DFR; CaMV 35S: ds carnDFR: 35S 3′ transgenes
#Tg = total number of transgenic carnation lines produced
CC = “Color Change” -the number of events produced that had a shift in petal color towards the purple range
[0200] The transgenic plants are assessed for flower color as described above and lines with novel flower color (as compared to controls) are selected for commercialization.
[0201] Those skilled in the art will appreciate that the invention described herein is susceptible to variations and modifications other than those specifically described. It is to be understood that the invention includes all such variations and modifications. The invention also includes all of the steps, features, compositions and compounds referred to or indicated in this specification, individually or collectively, and any and all combinations of any two or more of said steps or features.
BIBLIOGRAPHY
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Winkel-Shirley, Plant Physiol. 127:1399-1404, 2001b | The invention relates to genetically engineered plants with altered inflorescence. Plants such as spray carnations are transformed with a non-indigenous flavonoid 3′,5′ hydroxylase (F3′5′H) and dihydroflavanol-4-reductase (DFR) in conjunction with a genetic suppressor of indigenous DFR. Preferably the substrate specificity of the indigenous DFR is different to the non-indigenous DFR in order to enhance the colour of the inflorescence. | 2 |
RELATED APPLICATIONS
[0001] This application is a continuation application of U.S. patent application Ser. No. 12/773,453, filed May 4, 2010, currently pending, which claims priority to U.S. Provisional Patent Application No. 61/175,454, filed May 4, 2009. The specifications of each of these applications is herein incorporated by reference.
FIELD
[0002] The invention generally relates to an apparatus and a method for providing haptic feedback.
BACKGROUND INFORMATION
[0003] Handheld electronic devices, such as mobile phones, personal digital assistants (PDAs), pocket personal computers (PCs), gamepads, and camcorders, generally have multiple of buttons that allow one to interface with the device by inputting information. The capabilities of these devices are increasing while their size and weight are decreasing to enhance their portability. For example, mobile phones, in addition to their traditional role as voice-communication devices, now include functions traditionally associated with other devices, such as electronic games, PDAs, and digital cameras. At the same time, consumers seek smaller, lighter devices.
[0004] To support these multiple functions, a screen display is often used. Thus, the area on devices devoted to user input, i.e., the activating or input area, is becoming increasingly complex in terms of the number of functions available to be input, while the physical size of the input area is decreasing. Moreover, the available size of the input area must compete with the size of the visual display.
[0005] To permit effective interaction with these devices, visual and audio cues or feedback are provided by the conventional device. In addition to conventional visual and audio feedback, some of these devices attempt to enhance the effectiveness of device feedback by providing tactile cues or feedback. Some devices utilize structural tactile methods. One such example is to provide raised surfaces on the input surface, e.g., keypad, of the device. Such methods, however, are inherently static and thus cannot offer a wide array of, or effective, tactile feedback.
[0006] Active methods of providing tactile feedback include incorporating haptics into handheld electronic devices. These active methods of providing haptic cues generally include vibrating the entire device. Some devices have incorporated haptic feedback into a surface of the device instead of vibrating the entire device. In such devices, the haptic feedback is provided to the input area, i.e., the activating area. However, the limited size of the input area in a handheld device provides a very limited area in which to provide meaningful haptic feedback. Furthermore, the amount of physical contact with the input area is generally limited to a small surface of a finger while inputting information to the device. Moreover, in typical active methods, the frequencies at which the devices are vibrated have been in very limited ranges—typically between 20 Hz and 28 Hz. The number of haptic cues that can be conveyed in such a range is very limited.
SUMMARY
[0007] One embodiment is a handheld apparatus that includes a top surface that includes a touch screen defining a plurality of keys, and a bottom surface on an opposite side of the first surface. The apparatus further includes a processor and an actuator coupled to the processor and located on the bottom surface. The processor is adapted to detect an object moving across the keys and in response generate an actuation signal to the actuator to generate a haptic feedback on the back surface.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is a perspective view of a mobile phone according to an embodiment of the present invention.
[0009] FIG. 2 is a perspective view of a surface of an off-activating area of the mobile phone of FIG. 1 .
[0010] FIG. 3 is a perspective view of another surface of the off-activating area of the mobile phone of FIG. 1 .
[0011] FIG. 4 is a perspective view of an internal surface of the mobile phone of FIG. 1 .
[0012] FIG. 5 is a block diagram of an embodiment of a method according to the present invention.
[0013] FIG. 6 is a block diagram of another embodiment of a method according to the present invention.
[0014] FIG. 7 is a perspective view of a text communication device according to another embodiment of the present invention.
[0015] FIG. 8 is a perspective view of an off-activating area of the text communicating device of FIG. 7 .
[0016] FIG. 9 is a perspective view of a second mobile phone according to another embodiment of the invention.
[0017] FIG. 10 is a plan view of an off-activating area of the mobile phone of FIG. 9 .
[0018] FIG. 11 is a perspective view of a camcorder according to another embodiment of the invention.
[0019] FIG. 12 is a perspective view of a gamepad according to another embodiment of the invention.
[0020] FIG. 13 is a perspective view of an off-activating surface of the gamepad of FIG. 12 .
[0021] FIG. 14 is a perspective view of a touch surface of a device according to various embodiments of the invention.
[0022] FIG. 15 is a perspective view of an off-activating surface of a device according to various embodiments of the invention.
[0023] FIGS. 16A and 16B are perspective views of an actuating paddle assembly according to various embodiments of the invention.
DETAILED DESCRIPTION
[0024] Embodiments of the present invention include products and processes for providing haptic feedback at an area different than the input area. In some interface devices, kinesthetic feedback (such as, without limitation, active and passive force feedback), and/or tactile feedback (such as, without limitation, vibration, texture, and heat), is also provided to the user, more generally known collectively as “haptic feedback.” In certain embodiments, haptic feedback is provided only at an area different from the input area. In other embodiments, haptic feedback is also provided at the input area. The invention may be embodied in handheld devices, such as mobile phone, PDAs, pagers, and camcorders, but may be embodied in other devices as well.
[0025] FIG. 1 is a perspective view showing a mobile phone 100 according to an embodiment of the present invention. The phone 100 includes a first surface 110 , a second surface 120 , and a plurality of walls 130 . The plurality of walls 130 define a volume 140 (shown in FIGS. 3 and 4 ). As shown in FIG. 1 , the walls 130 are coupled to the first surface 110 and the second surface 120 . The first surface 110 and the second surface 120 may be distinct. While the first and second surfaces 110 , 120 shown in FIG. 1 are separate from one another. In an alternate embodiment, the first and second surfaces 110 , 120 can be contiguous.
[0026] The embodiment shown in FIGS. 1-4 includes a means for receiving an input signal. The means for receiving an input signal includes means for detecting a plurality of distinct pressures. The means for receiving an input signal and the means for detecting a plurality of distinct pressures in the embodiment shown in the FIG. 1 includes a keypad 114 , a switch 116 , and a touch-sensitive screen 118 . The keypad 114 , the switch 116 , and the touch-sensitive screen 118 are described further below.
[0027] Other means for receiving an input signal and means for detecting a plurality of distinct pressures may be used in other embodiments, for example, a D-pad, scroll wheel, and toggle switch. Structures described herein for receiving an input signal and for detecting a plurality of distinct pressures, or other structures may be used. Any suitable structure that can receive an input signal and that can detect a plurality of distinct pressures may be used.
[0028] Disposed in the first surface 110 are several input elements 112 . Other embodiments may include one input element (such as a touch-screen). The input elements 112 shown in FIG. 1 include the keypad 114 , switch 116 , and touch-sensitive screen 118 . The touch-sensitive screen 118 is disposed in a video display screen 119 . In other embodiments, input elements can include, for example, D-pads, scroll wheels, and toggle switches.
[0029] Information—through the generation of a signal—is generally input into the phone 100 through the input elements 112 disposed in the first surface 110 (hereinafter referred to as the “input surface”). Information can be input by physically contacting the input elements 112 with a digit of a hand, or with a device, such as a stylus. Alternatively, data can be input in the phone 100 remotely. For example, data can be transmitted wirelessly from a remote processor (not shown) to the phone 100 . In another example, the phone 100 can be placed in a cradle-like device (not shown), which is operative to communicate with the remote processor and the phone 100 . Data can be entered into the phone 100 placed in the cradle-like device through the remote processor by keying in data on a keyboard, which is operative to communicate with the remote processor.
[0030] FIG. 2 shows an exterior surface 124 of the second surface 120 (hereinafter referred to as the “off-activating surface” to indicate that it is different from the input surface) of the phone 100 . The off-activating surface 120 is formed from a battery cover panel 150 . Alternatively, an off-activating surface can be formed of a separate panel (not shown) coupled with the phone. The off-activating surface 120 shown is formed of a flexible material. Alternatively, the off-activating surface 120 can include a flexural member. In one embodiment, the off-activating surface 120 is formed of plastic. Alternatively, any other suitable material can be used.
[0031] In the embodiment shown in FIG. 2 , two grooves 122 are disposed in the off-activating surface 120 . The grooves 122 increase the flexibility of the off-activating surface 120 . The term “flexibility” refers to any displacement that is generally perceptible—by sight, sound, or touch—to one observing or holding the phone. Increased flexibility of the off-activating surface 120 provides a greater range of frequencies—especially those frequencies detectable by the hand—at which the off-activating surface 120 can vibrate. Preferably, the grooves 122 are disposed through an entire thickness of the off-activating surface 120 . Alternatively, the grooves 122 can be disposed partially through the off-activating surface 120 . The grooves 122 can be formed in the off-activating surface 120 during molding of the battery cover panel 150 . Alternatively, the grooves 122 can be formed into the battery cover panel 150 subsequent to molding the battery cover panel 150 .
[0032] In one embodiment, the grooves 122 extend substantially along a major length of the battery cover panel 150 . Alternatively, the grooves 122 can extend in any suitable length along the battery cover panel 150 . In one embodiment, the grooves 122 are disposed substantially parallel and proximate to the edges 152 of the battery cover panel 150 . Alternatively, the grooves 122 can be disposed in any other suitable configuration. The configuration, i.e., length, depth, shape, number and position of the grooves 122 can be varied to obtain the desired resonant characteristics of the off-activating surface 120 .
[0033] In one embodiment, formed in the exterior surface 124 of the off-activating surface 120 is a plurality of channels 180 . The channels 180 shown are recessed to accept digits of a hand. The channels 180 guide a user's hand when holding the phone 100 and maximize the amount of physical contact between the hand and the off-activating surface 120 .
[0034] The embodiment shown in FIGS. 1-4 includes a means for providing haptic feedback and a means for producing a plurality of distinct haptic sensations. The means for providing haptic feedback and the means for producing a plurality of distinct haptic sensations in the embodiment shown in FIGS. 1-4 comprises an actuator 160 in combination with a local processor (not shown). The actuator 160 and the local processor are described further below. Other means for providing haptic feedback and for producing a plurality of distinct haptic sensations may be used in other embodiments. For example, a voice coil and a permanent magnet, rotating masses, a piezo material such as quartz, Rochelle Salt, and synthetic polycrystalline ceramics, piezoelectric ceramics, piezoelectric films, and electroactive polymers can be used. Additionally, a remote processor can be used. Structures described herein for providing haptic feedback and for producing a plurality of distinct haptic sensations, or other structures may be used. Any suitable structure that can provide haptic feedback and that can produce a plurality of distinct haptic sensations may be used.
[0035] FIG. 3 is a perspective view of an interior surface 126 of the off-activating surface 120 of the phone 100 . As can be seen in FIG. 3 , the grooves 122 are disposed entirely through the battery cover panel 150 from the exterior surface 124 of the off-activating surface 120 to the interior surface 126 of the off-activating surface 120 . Disposed in the volume 140 is an actuator 160 . In other embodiments, two or more actuators are so disposed.
[0036] The actuator 160 shown in FIGS. 3 and 4 includes an actuator magnet 162 and an actuator voice coil 164 . In one embodiment, the actuator magnet 162 is a permanent magnet and the actuator voice coil 164 is an electromagnet. Alternatively, the actuator 160 can be formed of a piezo material such as quartz, Rochelle Salt, and synthetic polycrystalline ceramics. Other alternative actuators can include rotating masses, piezoelectric ceramics, piezoelectric films, and electroactive polymers. Any other suitable actuator can be used. Piezo material is bi-directional in its displacement, and actuates when an electric field is applied to it. In one embodiment, the actuator 160 is disposed proximate the base 154 of the battery cover panel 150 . Alternatively, the actuator 160 can be disposed in any other suitable area of the volume 140 .
[0037] In the embodiment shown in FIG. 3 , the actuator 160 is coupled to the off-activating surface 120 . As shown in FIG. 3 , the actuator 160 is coupled directly to the interior surface 126 of the off-activating surface 120 by the actuator magnet 162 . Alternatively, the actuator 160 can be coupled to the off-activating surface 120 by a coupling (not shown), i.e., an intermediary element. Alternatively, the actuator 160 can indirectly, i.e., without a direct physical connection, actuate the off-activating surface 120 by transmitting energy, such as sound waves or electromagnetic pulses, to the off-activating surface 120 .
[0038] FIG. 4 is a perspective view of an internal surface of the phone 100 of FIGS. 1-3 . The actuator voice coil 164 is coupled to a rigid surface 170 . In an alternative embodiment, the actuator voice coil 164 is coupled to a dampening member. A dampening member is either inflexible itself or, over a period of time, deadens or restrains physical displacement. The rigid surface 170 is disposed in the volume 140 of the phone 100 . In one embodiment, the rigid surface 170 is a PC board of the phone 100 . Alternatively, the actuator voice coil 164 can be coupled with any other suitable surface. The actuator voice coil 164 shown is disposed proximate the actuator magnet 162 . Alternatively, the actuator voice coil 164 can be disposed in any other suitable location in the volume 140 .
[0039] The actuator voice coil 164 is electrically connected to the power supply (not shown) of the phone 100 —generally the phone 100 is powered by a direct current (DC) power source, such as a battery. The actuator voice coil 164 is electrically connected to the power supply of the phone 100 by a first power supply wire 166 and a second power supply wire 168 . Alternatively, the actuator voice coil 164 can have a power source (not shown) separate from the power source of the phone 100 .
[0040] The rigid surface 170 preferably remains substantially static with respect to the off-activating surface 120 . The term “substantially static” does not mean that the rigid surface 170 is completely devoid of any measurable movement. The rigid surface 170 can be displaced when the actuator 160 imparts energy to actuate the off-activating surface 120 . Rather, “substantially static” means that any displacement of the rigid surface 170 is generally imperceptible, or only minimally perceptible, to one observing or holding the phone 100 . Alternatively, the rigid surface 170 can be displaced when the actuator 160 causes the off-activating surface 120 to actuate such that it is perceptible to one observing or holding the phone 100 . The rigid surface 170 can be displaced at a same or different frequency than that at which the off-activating surface 120 actuates.
[0041] The actuator 160 shown is operative to actuate the off-activating surface 120 at a frequency in a range between approximately 10 Hz and 300 Hz. When the actuator voice coil 164 is energized by the power source of the phone 100 , the actuator magnet 162 is displaced toward the actuator voice coil 164 . As the actuator magnet 162 is coupled with the off-activating surface 120 , the off-activating surface 120 is also displaced toward the actuator voice coil 164 when the actuator voice coil 164 is energized.
[0042] Varying the amount of current to the actuator voice coil 164 can vary the amount of displacement of the actuator magnet 162 toward the actuator voice coil 164 . Thus, the amount of displacement of the off-activating surface 120 can be regulated. When the actuator voice coil 164 is de-energized, the actuator magnet 162 is no longer displaced toward the actuator voice coil 164 , and returns substantially to its original position. Likewise, the off-activating surface 120 returns substantially to its original position.
[0043] Repeatedly energizing and de-energizing the actuator voice coil 164 causes the actuator magnet 162 , as well as the off-activating surface, to reciprocate between its original position and a position proximate the actuator voice coil 164 . Thus, variations in the current delivered to the actuator voice coil 164 and the period between energizing and de-energizing the actuator voice coil resonates the off-activating surface 120 .
[0044] The embodiment shown in FIGS. 1-4 includes a means for sending an actuation signal and a means for varying at least one of the frequency, waveform and magnitude of the haptic sensations. The means for sending an actuation signal and the means for varying at least one of the frequency, waveform and magnitude of the haptic sensations comprise the local processor. The local processor is described further below. Other means for determining pressure may be used in other embodiments. Other structures may be used, for example a remote processor. Any structure that can send an actuation signal and that can vary at least one of the frequency, waveform and magnitude can be used.
[0045] In one embodiment, a local processor (not shown) controls the actuation of the off-activating surface 120 by regulating the current delivered to the actuator voice coil 164 , the duration of the current delivered to the actuator voice coil 164 , the time between cycles of energizing the voice coil 164 , and the number of cycles of energizing the voice coil 164 . These conditions, i.e., frequency, waveform, and magnitude, can be varied to obtain desired resonant characteristics of the off-activating surface 120 . Alternatively, the processor can be remote, i.e., separate from the phone 100 . Thus, haptic feedback can be provided to the off-activating surface 120 .
[0046] The local processor monitors the input elements 112 in the phone 100 . When a plurality of input elements 112 is included, the processor can either monitor each input element 112 sequentially or in parallel. Monitoring the input elements 112 is preferably done as a continuous loop function.
[0047] The processor is in communication with the input elements 112 to receive input signals therefrom. The processor can also receive additional information from the input elements 112 , including the position of the input elements 112 and the amount of pressure applied to the input elements 112 . In one embodiment, the input signal includes information related to the amount of pressure applied to the input elements 112 , information related to the position of the input elements 112 , or a combination of information about pressure and position. In addition to being in communication with the input elements 112 , the processor is in communication with the actuator 160 to produce a haptic response in the actuator 160 corresponding to the input or input signal received by the actuator 160 from the input elements 112 .
[0048] The processor is located in a suitable location according to the needs of the device in which it is placed. In one embodiment, the processor is coupled (not shown) to the rigid surface 170 . Suitable processors include, for example, digital logical processors capable of processing input, executing algorithms, and generating output as needed to create the desired haptic feedback in the off-activating surface 120 in response to the inputs received from the input elements 112 .
[0049] Such processors can include a microprocessor, an Application Specific Integrated Circuit (ASIC), and state machines. Such processors include, or can be in communication with media, for example computer readable media, which stores instructions that, when executed by the processor, cause the processor to perform the steps described herein as carried out, or assisted, by a processor.
[0050] One embodiment of a suitable computer-readable medium includes an electronic, optical, magnetic, or other storage or transmission device capable of providing a processor, such as the processor in a web server, with computer-readable instructions. Other examples of suitable media include, but are not limited to, a floppy disk, CD-ROM, magnetic disk, memory chip, ROM, RAM, ASIC, configured processor, all optical media, all magnetic tape or other magnetic media, or any other medium from which a computer processor can read. Also, various other forms of computer-readable media may transmit or carry instructions to a computer, including a router, private or public network, or other transmission device or channel.
[0051] FIG. 5 shows an embodiment of a method 600 of providing haptic feedback to a location other than an input area. The method 600 may be employed in the phone 100 described above, and items shown in FIGS. 1-4 are referred to in describing FIG. 5 to aid understanding of the embodiment 600 shown. However, embodiments of methods according to the present invention may be employed in a wide variety of devices, including, without limitation, gamepads, PDAs, pagers, and automotive structures.
[0052] Referring to FIG. 5 , a user activates an input device (such as a button 112 ) on a first area 110 of the mobile telephone 100 . The input device 112 provides an input signal, comprising an indication that the input device 112 has been activated. In the embodiment shown, the input signal is received by a local processor (not shown) within the device 100 . In other embodiments, the input signal is received by an actuator, a remote processor, or other product.
[0053] Still referring to FIG. 5 , the next step 620 in the method shown 600 comprises providing haptic feedback to a second area 120 that is different from the input device 112 . In the embodiment shown, this step 620 comprises the local processor sending an actuation signal to an actuator 160 that is in communication with the second area 120 . The actuation signal comprises an indication that the actuator 160 should actuate (e.g., vibrate). The actuator 160 receives the actuation signal, and actuates. The communication between the second area 120 and the actuator 160 is configured such that the actuator's actuation provides haptic feedback (in the form of vibrations in the embodiment shown) to the second area 120 . In other embodiments, this step 620 may comprise the actuator 160 receiving the input signal from the input device, and then actuating to provide haptic feedback to the second area 120 .
[0054] Referring still to the embodiment shown in FIG. 5 , different input signals generate different actuation signals, and different input devices are configured to provide different input signals. In other embodiments, the processor includes an algorithm that is configured to provide desired haptic feedback in response to designated input signals or series of input signals.
[0055] As discussed above, in one embodiment, the actuator is a voice coil. Alternatively, the actuator can be a piezoceramic material. The operation of actuators has been described above and will not be repeated here. The actuator is in communication with a feedback area. The actuator can provide haptic feedback by actuating the feedback area. As discussed above, different haptics are provided by regulating the current delivered to the actuator, the duration of the current delivered to the actuator, the time between cycles of energizing the actuator, and the number of cycles of energizing the actuator. These conditions can be varied to produce a variety of haptics to the feedback area.
[0056] FIG. 6 shows an embodiment of a method 700 of providing haptic feedback to a feedback area of a device, such as the phone 100 described above. As indicated by block 710 , the method 700 includes disposing an actuator in a volume formed by a plurality of walls. As discussed above, the actuator can be formed from a voice coil and a permanent magnet. Alternatively, the actuator can be formed of a piezo material, such as quartz, Rochelle Salt, and synthetic polycrystalline ceramics. In one embodiment, the actuator is coupled to a rigid surface disposed in the volume, and is electrically connected to a power supply and a processor disposed in the volume. Alternatively, the actuator can be configured to communicate with a remote power supply. Likewise, the actuator can be configured to communicate with a remote processor. For example, the actuator can be configured to communicate with a remote processor wirelessly.
[0057] As indicated by block 720 , the method 700 includes coupling an input area and a feedback area with the walls. Preferably, the input and feedback areas are distinct. In one embodiment, the input and feedback areas are separate from one another. Alternatively, the input and feedback areas can be contiguous. As shown by block 730 , the method includes disposing an input element in the input surface. As described above, the input element is preferably a keypad, a switch, and a touch-sensitive screen. Alternative input elements are described above.
[0058] As indicated by block 740 , the method includes communicating the actuator with the feedback area. As described above, the actuator can directly contact the feedback area. With reference to the embodiment of the apparatus described above, the actuator magnet can be coupled directly to the feedback area. Alternatively, the actuator can be indirectly coupled to the feedback area. For example, the actuator can transmit energy, such as sound waves or electromagnetic pulses to the feedback area. In one embodiment, the method 700 includes disposing a coupling between the actuator and the feedback area. In one embodiment, the coupling is a mechanical linkage although any other suitable coupling can be used. The method 700 further includes communicating one end of the coupling with the actuator and communicating the other end of the coupling with the feedback area. In another embodiment, the method 700 includes actuating the feedback area at a first frequency. In one embodiment, the first frequency is in a range between approximately 10 Hz and 300 Hz.
[0059] In one embodiment the method 700 includes forming at least one groove in the feedback area. The configuration, i.e., length, depth, width, number, and shape, of the grooves can be varied to obtain varying resonant characteristics of the feedback area. Actuating the off-activating surface with a voice coil and a permanent magnet has been described above.
[0060] Alternate embodiments of the apparatus according to the present invention will next be described with reference to FIGS. 7-17 . Descriptions of like structures with the previously-described embodiments will not be repeated.
[0061] FIG. 7 shows a perspective view of a text communication device 300 according to another embodiment of the present invention. An input surface 310 of the text communication device 300 preferably includes a plurality of input elements 312 , a display screen 317 , and a base 319 . The plurality of input elements 312 includes a keypad 314 and a touch-sensitive screen 318 disposed in the display screen 317 . Alternatively, there may only be one input element 312 , such as a touch-sensitive screen 318 .
[0062] Referring now to FIG. 8 , a perspective view of an off-activating surface 320 of the text communication device 300 of FIG. 7 is shown. The off-activating surface 320 includes an exterior surface 324 . Disposed in the exterior surface 324 of the off-activating surface 320 are a groove 322 and a plurality of channels 380 . The channels 380 shown are recessed to accept digits of a hand. The channels 380 guide a user's hand when holding the text communication device 300 and maximize the amount of physical contact between the hand and the off-activating surface 320 .
[0063] The groove 322 is formed through an entire thickness of the off-activating surface 320 . Preferably, the groove 322 is substantially continuous and forms a substantially circular panel 328 in the off-activating surface 320 . Alternatively, the groove 322 can form any other suitable configuration. In this embodiment, the panel 328 is cantilevered from the off-activating surface 320 . Thus, the off-activating surface 320 does not actuate with a uniform frequency. For example, the portion of the panel 328 proximate the base 319 actuates with a greater frequency than the off-activating surface proximate the display screen 317 . The actuator (not shown) is disposed proximate the panel 328 . As described above, the actuator is in one embodiment coupled directly to the panel 328 . Alternatively, the actuator can be coupled indirectly with the panel 328 .
[0064] Referring now to FIG. 9 , a perspective view of a mobile phone 400 according to another embodiment of the invention is shown. An input surface 410 of the mobile phone 400 includes a plurality of input elements 412 , a display screen 417 , and a base 419 . In one embodiment, the input elements 412 include a keypad 414 and a touch-sensitive screen 418 disposed in the display screen 417 . Alternatively, there can only be one input element 412 , such as the touch-sensitive screen 418 .
[0065] Referring now to FIG. 10 , a perspective view of an off-activating surface 420 of the mobile phone 400 of FIG. 9 is shown. The off-activating surface 420 includes an exterior surface 424 . Disposed in the exterior surface 424 of the off-activating surface 420 are first and second grooves 422 and 423 and a plurality of channels 480 . The channels 480 shown are recessed to accept digits of a hand. The channels 480 guide a user's hand when holding the phone 400 and maximize the amount of physical contact between the hand and the off-activating surface 420 .
[0066] The first and second grooves 422 and 423 are formed through an entire thickness of the off-activating surface 420 . In one embodiment, the first and second grooves 422 and 423 have substantially the same configuration. Alternatively, the first and second grooves 422 and 423 can be formed of different configurations. In one embodiment, the first and second grooves 422 and 423 are substantially continuous and form substantially circular first and second panels 428 and 429 in the off-activating surface 420 . Alternatively, the first and second grooves 422 and 423 can form any other suitable panel.
[0067] In this embodiment, first and second panels 428 and 429 are cantilevered from the off-activating surface 420 . Thus, the off-activating surface 420 does not actuate with a uniform frequency. For example, first and second panels 428 and 429 proximate the display screen 417 actuate with a greater frequency than the off-activating surface 420 proximate the base 419 .
[0068] In one embodiment, a first actuator (not shown) is disposed proximate the first panel 428 and a second actuator (not shown) is disposed proximate the second panel 429 . Alternatively, a single actuator (not shown) can be coupled with both or either the first and second panels 428 and 429 , as required. As described above, the first and second actuators can be coupled directly to the first and second active panels 428 and 429 . Alternatively, the first and second actuators can be coupled indirectly with the first and second active panels 428 and 429 . The single actuator can be coupled directly or indirectly with the first and second active panels 428 and 429 .
[0069] Referring now to FIG. 11 , a camcorder 500 according to another embodiment of the invention is shown. An input surface 510 of the camcorder 500 includes an input element 512 . The input element 512 shown is a touch-sensitive screen, which is disposed in a display screen 517 . When the input surface 510 is fully extended, it is disposed substantially orthogonal to an off-activating surface 520 . The off-activating surface 520 includes an exterior surface 524 . Disposed in the exterior surface 524 are first and second grooves 522 and 523 and a plurality of channels 580 .
[0070] As described above, the channels 580 shown are recessed to accept digits of a hand. The channels 580 guide a user's hand when holding the camcorder 500 and maximize the amount of physical contact between the hand and the off-activating surface 520 . In one embodiment, first and second grooves 522 and 523 are formed through an entire thickness of the off-activating surface 520 . Alternatively, the first and second grooves 522 and 523 can be formed partially through the thickness of the off-activating surface 520 .
[0071] In one embodiment, the grooves 522 and 523 have substantially the same configuration. Alternatively, the grooves 522 and 523 can be formed of different configurations. For example, the grooves 522 and 523 can be formed linearly and substantially along a perimeter of the off-activating surface 520 , similar to that described above in FIGS. 1-4 . In one embodiment, the grooves 522 and 523 are substantially continuous and form substantially circular first and second panels 528 and 529 in the off-activating surface 520 . Alternatively, the first and second grooves 522 and 523 can form any other suitable panel.
[0072] The first and second panels 528 and 529 are cantilevered from the off-activating surface 520 . As described above, the off-activating surface 520 does not actuate with a uniform frequency. As described above, a first actuator (not shown) is disposed proximate the first panel 528 and a second actuator (not shown) is disposed proximate the second panel 529 . Alternatively, a single actuator (not shown) can be coupled with both or either the first and second panels 528 and 529 , as required. As described above, the first and second actuators can be coupled directly with the first and second panels 528 and 529 . Alternatively, the first and second actuators can be coupled indirectly with the first and second panels 528 and 529 . The single actuator can be coupled directly or indirectly with the first and second panels 528 and 529 .
[0073] FIG. 12 shows a perspective view of a gamepad 800 according to another embodiment of the invention. An input surface 810 of the gamepad 800 includes a plurality of input elements 812 , including buttons 814 , a directional controller 815 , and joysticks 816 . Alternatively, any other suitable number or combination of input elements can be used. The gamepad 800 also includes two wings 818 to facilitate grasping the device with two hands.
[0074] As shown in FIG. 13 , the gamepad 800 includes an off-activating surface 820 . The off-activating surface 820 includes an exterior surface 824 . Disposed in the exterior surface 824 are first and second grooves 822 and 823 and a plurality of channels 880 . The first and second grooves 822 and 823 and the channels 880 are formed proximate the wings 818 .
[0075] The channels 880 shown are recessed to accept digits of a hand. The channels 880 guide a user's hand when holding the gamepad 800 and maximize the amount of physical contact between the hand and the off-activating surface 820 . In one embodiment, first and second grooves 822 and 823 are formed through an entire thickness of the off-activating surface 820 . In one embodiment, the grooves 822 and 823 have substantially the same configuration. Alternatively, the grooves 822 and 823 can be formed of different configurations. For example, the grooves 822 and 823 can be formed to substantially follow the perimeter of the wings 818 . In one embodiment, the grooves 822 and 823 are substantially continuous and form substantially circular first and second panels 828 and 829 in the off-activating surface 820 . Alternatively, the first and second grooves 822 and 823 can form any other suitable panel.
[0076] The first and second panels 828 and 829 are cantilevered from the off-activating surface 820 . In one embodiment, the first and second panels 828 and 829 are also input elements 812 . As described above, the off-activating surface 820 does not actuate with a uniform frequency. In one embodiment, a first actuator (not shown) is disposed proximate the first panel 828 and the second panel 829 . Alternatively, a single actuator (not shown) can be coupled with both or either the first and second panels 828 and 829 , as required. The first and second actuators can be coupled indirectly with the first and second panels 828 and 829 .
[0077] One problem associated with “soft” keyboards (e.g., a “keyboard” user interface displayed and implemented with a touch screen) is a lack of tactile feedback to a user of the soft keyboard. Replacing mechanical keys with keys on the soft keyboard remove tactile information provided by the mechanical keys when pressing as well as 1 ) the static haptic information provided by the edges of the mechanical keys, and 2 ) the kinesthetic information provided by the normal travel of the button when pressed.
[0078] Certain forms of haptic feedback have brought back part of the tactile information in the form of “clicks” generated by, for example, vibrating motors. However this haptic feedback still does not completely recreate completely the interaction of the original mechanical keys. As a result, the interaction with soft keyboards may be slow, and not satisfying from a user experience point of view.
[0079] Another problem associated with soft keyboards is occlusion with the soft keyboards implemented in hand held devices. The size of the keys can be very small and even medium size fingers may partially cover, and in some cases completely cover, more than one key at the time. This often results in an incorrect key being recognized as being pressed, thereby slowing down text entry and increasing the error rate of soft keyboards when compared to mechanical keyboards in hand held devices.
[0080] FIG. 14 illustrates a perspective view of a touch surface 1410 of a device 1400 according to various embodiments of the invention. As illustrated, touch surface 1410 includes a soft keyboard 1440 having a plurality of keys such as a first key 1420 and a second key 1430 . While described in reference to soft keyboard 1440 , the invention is not so limited and may pertain to various soft keys implemented in connection with a touch screen as would be appreciated.
[0081] FIG. 15 illustrates a perspective view of an off-activating surface 1510 of device 1400 according to various embodiments of the invention. As illustrated, off-activating surface 1510 includes two portions 1520 , each of which has disposed therein an actuating paddle 1530 . While two actuating paddles 1530 are illustrated in FIG. 15 , other numbers of actuating paddles may be used. While actuating paddles 1530 are illustrated as vertically arranged, horizontally aligned with one another, and substantially parallel, other configurations may be used. For example, actuating paddles 1530 may be horizontally arranged; aligned with vertical and/or horizontal offsets from one another, and/or not parallel. Other configurations may be used as would be appreciated. While actuating paddles 1530 are illustrated in FIG. 15 as a block, any shape and/or size may be used, symmetrical or otherwise as would be appreciated. Portions 1520 in one embodiment are rubber housing that allows a user to feel the rotation of paddles 1530 through the rubber.
[0082] According to various embodiments of the invention, either or both of actuating paddles 1530 operate in connection with a user touching (or in some implementations proximate to) a key, such as key 1420 , or an edge of a key. In some embodiments of the invention, as a user holds device 1400 with thumbs proximate to touch surface 1410 and other fingers proximate to off-activating surface 1510 , one or both of actuating paddles 1530 provide haptic feedback to the user's other fingers as the user passes his/her thumbs over, across, or on a key, such as key 1420 . In particular, actuating paddles 1530 provide haptic feedback to the user in connection with an edge being traversed by at least one thumb. While described as operating in connection with thumbs on touch surface 1520 , other digits may be used, for example, when the user holds device 1400 in one hand and uses, for example, an index finger on another hand to interact with touch surface 1410 .
[0083] In some embodiments of the invention, actuating paddle 1530 moves when actuated to provide the haptic feedback. In some embodiments of the invention, actuating paddle 1530 moves by rotating back and forth by a small amount (e.g., 1-10 degrees or more) when actuated. In some embodiments, actuating paddle 1530 moves by rotating in a first direction in response to a digit moving left to right over touch screen 1410 and/or in a second direction in response to a digit moving right to left over touch screen 1410 . In some embodiments, actuating paddle 1530 moves by rotating by an amount in a first direction from a rest position and then returns to the rest position by rotating by the amount in the reverse direction. In some embodiments of the invention, actuating paddle 1530 moves by longitudinally translating by some amount when actuated. In some embodiments of the invention, actuating paddle 1530 moves by rotating and longitudinally translating in response to a digit moving over touch screen 1410 . In some embodiments of the invention, actuating paddle 1530 moves by translating in and out with respect to off-activating surface 1510 .
[0084] In some embodiments of the invention, the actuating paddle 1530 that is proximate to a user's right hand fingers provides haptic feedback to the user when the right thumb passes over, across or on a key. In some embodiments of the invention, the actuating paddle 1530 that is proximate to a user's left hand fingers provides haptic feedback to the user when the left thumb passes over, across or on a key. In some embodiments of the invention, both actuating paddles 1530 may move in response to fingers moving over, across, or on a key.
[0085] In some embodiments of the invention, device 1400 includes one or more detectors (not otherwise illustrated) for determining which hand is holding device 1400 . In some embodiments of the invention, device 1400 includes one or more detectors for determining whether both hands are holding device 1400 . In these embodiments of the invention, either or both actuating paddles 1530 may provide haptic feedback to the user depending on whether either or both hands are holding device 1400 .
[0086] In some embodiments of the invention, when, for example, touch surface 1410 includes a capacitive touch screen, one or more actuating paddles 1530 may provide haptic feedback to the user as one or more of the user's digits “hover” over one or more keys on soft keyboard 1440 . In this embodiment, the term “hover” could require either physical contact with a conventional touch screen, or close proximity to a more advanced touch screen that can sense the finger before it is in contact (i.e., a touch screen equivalent to a “mouse-over”).
[0087] FIG. 16 illustrates views of an actuating paddle assembly 1610 from different perspectives according to various embodiments of the invention. Actuating paddle assembly 1610 includes actuating paddle 1530 , a motor mount 1620 , a bearing 1630 , and an axle 1640 . A motor (not otherwise illustrated in FIG. 16 ) rests in motor mount 1620 and is coupled to axle 1640 . Axle 1640 is coupled to actuating paddle 1530 and bearing 1630 . The motor drives axle 1640 in either direction thereby rotating paddle 1530 to generate haptic feedback.
[0088] Instead of rotating paddles 1530 , in other embodiments different structures can be used to generate the haptic feedback on the oft-activating surface 1510 of device 1400 . In one embodiment, piezoelectric material can be placed directly on surface 1510 . The piezoelectric material will bow outwards when current is applied to it. The bowing can be felt by a user's fingers that are contacting the piezoelectric material. In this embodiment, the portion or housing 1530 may be eliminated because a user can directly contact the piezoelectric material. In one embodiment, the piezoelectric material may be Macro Fiber Composite (“MFC”) material from Smart Material Corp., or may be any monolithic or composite piezo.
[0089] In one embodiment, the function of the paddle or piezoelectric material or strip is to push against or move the user's finger a small amount to generate haptic feedback. Any other type of actuator that can perform this function can be used. For example, a pin that moves up and down can be used as the actuator.
[0090] Several embodiments are specifically illustrated and/or described herein. However, it will be appreciated that modifications and variations of the disclosed embodiments are covered by the above teachings and within the purview of the appended claims without departing from the spirit and intended scope of the invention. | A handheld apparatus includes a top surface that includes a touch screen defining a plurality of keys, and a bottom surface on an opposite side of the first surface. The apparatus further includes a processor and an actuator coupled to the processor and located on the bottom surface. The processor is adapted to detect an object moving across the keys and in response generate an actuation signal to the actuator to generate a haptic feedback on the back surface. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a divisional of application Ser. No. 10/902,959 filed Aug. 2, 2004, now U.S. Pat. No. 7,442,686, which is a continuation in part of application Ser. No. 10/118,079 filed Apr. 9, 2002, now U.S. Pat. No. 6,855,688, which claims priority on Canadian Applications 2,342,970; 2,362,004; and 2,367,636 filed Apr. 12, 2001, Nov. 13, 2001 and Jan. 15, 2002, and claims priority of U.S. Provisional Application 60/506,162 filed Sep. 29, 2003 respectively. The entire content of these applications is hereby incorporated by reference.
FIELD OF THE INVENTION
The present invention relates to conjugate or fusion type proteins (polypeptides) comprising, for example, C3-like fusion proteins, C3 chimeric fusion proteins. Although, in the following, fusion-type proteins of the present invention will be particularly discussed in relation to the use to facilitate regeneration of axons and neuroprotection, it is to be understood that the fusion proteins may be exploited in other contexts.
The present invention in particular pertains to the field of mammalian nervous system repair (e.g. repair of a central nervous system (CNS) lesion site or a peripheral nervous system (PNS) lesion site), axon regeneration and axon sprouting, neurite growth and protection from neurodegeneration and ischemic damage.
The retina is part of the CNS, and this invention pertains to repair of the retina, neuroprotection in the retina, retinal trauma and disease, and ischemic damage to the retina. The invention in particular pertains to compositions and methods useful to treat diseases of the eye such as macular degeneration (such as wet macular degeneration and dry macular degeneration), Stargardt's Disease, Retinitis Pigmentosa, diabetic retinopathy, hypertensive retinopathy, occlusive retinopathy, and other diseases of the retina, including diseases comprising abnormal blood and fluid flow.
BACKGROUND OF THE INVENTION
Traumatic injury of the spinal cord results in permanent functional impairment. Most of the deficits associated with spinal cord injury result from the loss of axons that are damaged in the central nervous system (CNS). Similarly, other diseases of the CNS are associated with axonal loss and retraction, such as stroke, human immunodeficiency virus (HIV) dementia, prion diseases, Parkinson's disease, Alzheimer's disease, multiple sclerosis and glaucoma. Common to all of these diseases is the loss of axonal connections with their targets, and cell death. The ability to stimulate growth of axons from the affected or diseased neuronal population would improve recovery of lost neurological functions, and protection from cell death can limit the extent of damage. For example, following a white matter stroke, axons are damaged and lost, even though the neuronal cell bodies are alive, and stroke in grey matter kills many neurons and non-neuronal (glial) cells. Treatments that are effective in eliciting sprouting from injured axons are equally effective in treating some types of stroke (Boston life sciences, Sep. 6, 2000 Press release). Neuroprotective agents often tested as potential compounds that can limit damage after stroke. Compounds which show both growth-promotion and neuroprotection are especially good candidates for treatment of stroke and neurodegenerative diseases. Similarly, although the following discussion will generally relate to delivery of Rho antagonists, etc. to a traumatically damaged nervous system, this invention may also be applied to damage from unknown causes, such as during stroke, multiple sclerosis, HIV dementia, Parkinson's disease, Alzheimer's disease, prion diseases or other diseases of the CNS were axons are damaged in the CNS environment. Also, Rho is an important target for treatment of cancer and metastasis (Clark et al (2000) Nature 406:532-535), and hypertension (Uehata et al. (1997) Nature 389:990) and RhoA is reported to have a cardioprotective role (Lee et al. FASEB J. 15:1886-1884). Therefore, the new C3-like proteins are expected to be useful for a variety of diseases were inhibition of Rho activity is required.
It has been proposed to use various Rho antagonists as agents to stimulate regeneration of (cut) axons, i.e. nerve lesions; please see, for example, Canadian Patent application nos. 2,304,981 (McKerracher et al) and 2,300,878 (Strittmatter). These patent application documents propose the use of known Rho antagonists such as for example C3, chimeric C3 proteins, etc. (see blow) as well as substances selected from among known trans-4-amino (alkyl)-1-pyridylcarbamoylcyclohexane compounds (also see below) or Rho kinase inhibitors for use in the regeneration of axons. C3 inactivates Rho by ADP-ribosylation and is fairly non-toxic to cells (Dillon and Feig (1995) Methods in Enzymology: Small GTPases and their regulators Part. B.256:174-184).
While the following discussion will generally relate or be directed at repair in the CNS, the techniques described herein may be extended to use in many other diseases including, but not restricted to, cancer, metastasis, hypertension, cardiac disease, stroke, diabetic neuropathy, and neurodegenerative disorders such as stroke, Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis (ALS). Treatment with Rho antagonists would be used to enhance the rate of axon growth of peripheral nerves and thereby be effective for repair of peripheral nerves after surgery, for example after reattaching severed limbs. Also, treatment with our fusion compounds (proteins) is expected to be effective for the treatment of various peripheral neuropathies because of their axon growth promoting effects.
As mentioned above, traumatic injury of the spinal cord results in permanent functional impairment. Axon regeneration does not occur in the adult mammalian CNS because substrate-bound growth inhibitory proteins block axon growth. Many compounds, such as trophic factors, enhance neuronal differentiation and stimulate axon growth in tissue culture. However, most factors that enhance growth and differentiation are not able to promote axon regenerative growth on inhibitory substrates. To demonstrate that a compound known to stimulate axon growth in tissue culture most accurately reflects the potential for therapeutic use in axon regeneration in the CNS, it is important for the cell culture studies to include the demonstration that a compound can permit axon growth on growth inhibitory substrates. An example of trophic and differentiation factors that stimulate growth on permissive substrates in tissue culture, are neurotrophins such as nerve growth factor (NGF) and brain-derived growth factor. NGF, however, does not promote growth on inhibitory substrates (Lehmann, et al. (1999) 19: 7537-7547) and it has not been effective in promoting axon regeneration in vivo. Brain derived neurotrophic factor (BDNF) is not effective to promote regeneration in vivo either (Mansour-Robaey, et al. J. Neurosci. (1994) 91: 1632-1636). BDNF does not promote neurite growth on growth inhibitory substrates (Lehmann et al supra).
Targeting intracellular signaling mechanisms involving Rho and the Rho kinase for promoting axon regeneration has been proposed (see, for example, the above-mentioned Canadian Patent application nos. 2,304,981 (McKerracher et al)). For demonstration that inactivation of Rho promotes axon regeneration on growth inhibitory substrates, recombinant C3, a protein that inactivates Rho by ADP ribosylation of the effector domain was used. While such a C3 protein can effectively promote regeneration, it has been noted that such a C3 protein does not easily penetrate into cells, and high doses must therefore be applied for it to be effective. The high dose of recombinant C3 needed to promote functional recovery presents a practical constraint or limitation on the use of C3 in vivo to promote regeneration (Lehmann, et al. (1999) J. Neurosci. 19: 7537-7547; Morii, N and Narumiya, S. (1995) Methods in Enzymology, Vol 256 part B, pg. 196-206. In tissue culture studies, it has, for example, been determined that the minimum amount of C3 that can be used to induce growth on inhibitory substrates is 25 ug/ml (Lehmann, et al. (1999) J. Neurosci. 19: 7537-7547; Morii, N and Narumiya, S. (1995) Methods in Enzymology, Vol 256 part B, pg. 196-206. If the cells are not triturated, even this dose is ineffective. It has been estimated, for example, that at least 40 μg of C3 per 20 g mouse needs to be applied to injured mouse spinal cord or rat optic nerve (McKerracher, Canadian patent application No.: 2,325,842). Calculating doses that would be required to treat an adult human on an equivalent dose per weight scale up used for rat and mice experiments, it would be necessary to apply 120 mg/kg of C3 (i.e. alone) to the injured human spinal cord. The large amount of recombinant C3 protein needed creates significant problems for manufacturing, due to the large-scale protein purification and cost. It also limits the dose ranging that can be tested because of the large amount of protein needed for minimal effective doses.
Another related limitation with respect to the use of C3 to promote repair in the injured CNS is that it does not easily penetrate the plasma membrane of living cells. In tissue culture studies when C3 is applied to test biological effects it has been microinjected directly into the cell (Ridley and Hall (1992) Cell 70: 389-399), or applied by trituration of the cells to break the plasma membrane (Lehmann, et al. (1999) J. Neurosci. 19: 7537-7547, Jin and Strittmatter (1997) J. Neurosci. 17: 6256-6263). In the case of axon injury in vivo, the C3 protein is likely able to enter the cell because injured axons readily take up substances from their environment. However, C3-like proteins of the present invention are likely to act also on surrounding undamaged neurons and help them make new connections as well, thus facilitating recovery. After incomplete SCI, there is plasticity of motor systems attributed to cortical and subcortical levels, including spinal cord circuitry (Raineteau, O., and Schwab, M. E. (2001) Nat Rev Neurosci 2: 263-73). This plasticity may be attributed to axonal or dendritic sprouting of collaterals and synaptic strengthening or weakening. Additionally, it has been shown that sparing of a few ventrolateral fibers may translate into significant differences in locomotor performance since these fibers are important in the initiation and control of locomotor pattern through spinal central pattern generators (Brustein, E., and Rossignol, S. (1998) J Neurophysiol 80: 1245-67). It is well documented that reorganization of spared collateral cortical spinal fibers occurs after spinal cord injury and this contributes to functional recovery (Weidner et al, 2001 Proc. Natl. Acad. Sci. 98: 3513-3518). The process of reorganization and sprouting of spared fibers would be enhanced by treatment with C3-like proteins able to enter non-injured neurons. This would enhances spontaneous plasticity of axons and dendritic remodeling known to help functional recovery.
Other methods of delivery of C3 in vitro have been to make a recombinant protein that can be taken up by a receptor-mediated mechanism (Boquet, P. et al. (1995) Meth. Enzymol. 256: 297-306). The disadvantage of this method is that the cells needing treatment must express the necessary receptor. Lastly, addition of a C2II binding protein to the tissue culture medium, along with a C21N-C3 fusion toxin allows uptake of C3 by receptor-mediated endocytosis (Barthe et al. (1998) Infection and Immunity 66:1364). The disadvantage of this system is that much of the C3 in the cell will be restrained within a membrane compartment. More importantly, two different proteins must be added separately for transport to occur (Wahl et al. 2000. J. Cell Biol. 149:263), which make this system difficult to apply to for treatment of disease in vivo.
Retinitis pigmentosa is a retinal degeneration disease which manifests as night blindness, progressive loss of visual field and peripheral vision, eventually leading to total blindness; opthalmoscopic changes can consist in dark mosaic-like retinal pigmentation, attenuation of the retinal vessels, waxy pallor of the optic disc, and in the advanced forms, macular degeneration. In some cases there can be a lack of pigmentation. This disease is hereditary and the degeneration of retinal photoreceptor cell proceeds with increasingly narrower retinochoroidal blood vessel and circulatory disorders.
Diabetic retinopathy, a leading cause of blindness in type 1 and type 2 diabetics, is a complication of diabetes which produces damage to the blood vessels inside the retina. Diabetic retinopathy can have four stages: (1) mild nonproliferative retinopathy, wherein microaneurysms in the retina's blood vessels occur; (2) moderate nonproliferative retinopathy, wherein some blood vessels feeding the retina become blocked; (3) severe nonproliferative retinopathy, wherein many blood vessels to the retina are blocked, depriving several areas of the retina with their blood supply; and (4) proliferative retinopathy, wherein new, abnormal, thin-and fragile-walled blood vessels grow to supply blood to the retina, but which new blood vessels may leak blood to produce severe vision loss and blindness. Hemorrhages can occur more than once, often during sleep. Fluid can also leak into the center of the macula at any stage of diabetic retinopathy and cause macular edema and blurred vision. About 40 to 45 percent of Americans diagnosed with diabetes have some stage of diabetic retinopathy, and about half of the people with proliferative retinopathy also have macular edema.
Stargardt's disease, or fundus flavimaculatus, is a hereditary macular degenerative disorder. Most patients with the condition present in the teenage years with complaints of bilaterally reduced vision. Vision is commonly in the 20/40 range upon first presentation, but frequently falls to the 20/100 level within 4 or 5 years. Vision usually progressively, but gradually, declines beyond 20 years of age, perhaps to the 20/200 level, or worse. Patients will invariably have characteristic flecks in the retina, and these may occupy the macular area in early life. With progression of the disorder, the macula shows atrophy that is not unlike some cases of age related macular degeneration. However, this degree of atrophy is often present in the teens or early 20's. Some patients will develop choroidal neovascular membranes or vessels beneath the retina which may leak fluid or bleed. There is no known treatment that will delay or halt the progression of the disease.
Hypertensive retinopathy involves damage to the retina caused by high blood pressure which produces narrowing of and excess fluid oozing from blood vessels in the retina. The degree of retina damage (retinopathy) is graded on a scale of I to IV, wherein Group I comprises minimal narrowing of the retinal arteries; Group II comprises narrowing of the retinal arteries in conjunction with regions of focal narrowing and arteriovenous nicking; Group III comprises abnormalities seen in groups I and II, as well as retinal hemorrhages, hard exudation, and cotton-wool spots; and Group IV hypertensive retinopathy comprises abnormalities encountered in groups I through III, as well as swelling of the optic nerve head and macula, which can cause decreased vision. Control of high blood pressure (hypertension) is the only treatment for hypertensive retinopathy. Some patients with grade IV hypertensive retinopathy will have permanent damage to the optic nerve or macula. Hypertensive choroidopathy frequently accompanies hypertensive retinopathy when the changes of group IV, and sometimes those of group III, are present. In the acute phase, yellow spots are visible at the level of the retinal pigment epithelium. They are known as Elshnig Nodules. They are hyperfluorescent on fluorescein angiography and appear to occur secondary to fibrinoid necrosis within the choriocapillaris, leading to damage to the overlying retinal pigment epithelium. In severe cases, the intense leakage of plasma from these foci contributes to serous retinal detachment. Over a period of weeks, these spots become pigmented or depigmented. When the spots occur in a linear fashion, they are referred to as Siegrist's streaks.
Occlusive retinopathy or retinal vein occlusion, second only to diabetic retinopathy as a cause of visual loss due to retinal vascular disease, comprises both branch and central retinal vein occlusion in which a portion of the circulation that drains the retina of blood becomes blocked, causing back-up pressure in the capillaries, dilated blood vessels, hemorrhages, swelling (edema), and leakage of fluid and other constituents of blood in the distribution of the vein. An occlusion of the central retinal vein involves the entire retina. Complete vein blockage leads to intense hemorrhages and edema, and involved capillaries can cease to function and close off (ischemia or capillary non-perfusion). Complications of branch retinal vein occlusion include macular edema, macular ischemia (non-perfusion) and neovacularization (growth of new abnormal blood vessels). When the distribution of the vein involves the macula, bleeding and exudation or leakage occurs there to produce macular edema with blurred vision and loss of portions of the field of vision. Scar tissue may form on the surface of the retina to produce a macular pucker or an epiretinal membrane may result in distorted vision (metamorphopsia). With significant closure of capillaries, abnormal vessels may grow (neovascularization) and bleed into the overlying ocular cavity in the posterior part of the eye (vitreous hemorrhage) leading to retinal detachment. Central retinal vein occlusion is closure of the retinal vein located at the optic nerve; the occlusion can be non-ischemic or ischemic. Some central retinal vein occlusions are associated with a significant obstruction of capillaries or non-perfusion, and predisposition to neovascularization that occurs in front of the eye on the iris (rubeosis irides). These eyes may develop a very high pressure (neovascular glaucoma) due to obstruction of the fluid outflow channels, and experience severe vision loss, pain, and loss of the eye. Central retinal vein occlusion can produce macular edema and neovascularization in the back of the eye leading to vitreous hemorrhage and retinal detachment.
The Rho family GTPases regulates axon growth and regeneration. Inactivation of Rho with Clostridium botulinum C3 exotransferase (hereinafter simply referred to as C3) can stimulate regeneration and sprouting of injured axons; C3 is a toxin purified from Clostridium botulinum (see Saito et al., 1995, FEBS Lett 371:105-109; Wilde et al 2000. J. Biol. Chem. 275:16478). Compounds of the C3 family from Clostridium botulinum inactivate Rho by ADP-ribosylation and thus act as antagonists of Rho effect or function (Rho antagonists).
Degeneration of components of the retina can lead to partial or total blindness. Macular degeneration is a degeneration of the macular region of the retina in the eye. Degeneration of the macula causes a decrease in acute vision and can lead to eventual loss of acute vision. The wet form of macular degeneration is related to abnormal growth of blood vessels in the retina that can leak blood and can cause damage to photoreceptor cells.
Age-related macular degeneration (AMD) is a collection of clinically recognizable ocular findings that can lead to blindness.
Macular degeneration is a group of diseases that affect the central retina, or macula. There are two basic types of macular degeneration: “wet” and “dry”. In wet macular degeneration, there is an abnormal growth of new blood vessels. These new blood vessels break and leak fluid, causing damage to the central retina. This form of macular degeneration is often associated with aging. Approximately 90% of macular degeneration cases are dry macular degeneration. Vision loss can result from the accumulation of deposits in the retina called drusen, and from the death of photoreceptor cells. This process can lead to thinning and drying of the retina.
The findings of AMD include the presence of drusen, retinal pigment epithelial disturbance, including pigment clumping and/or dropout, retinal pigment epithelial detachment, geographic atrophy, subretinal neovascularization and disciform scar. Age-related macular degeneration is a leading cause of presently incurable blindness, particularly in persons over 55 years of age. Approximately one in four persons age 65 or over have signs of age-related maculopathy, and about 7% of persons age 75 or over have advanced macular degeneration with vision loss.
Drusen are opthalmoscopically visible, yellow-white hyaline excrescences or nodules of Bruch's membrane. Bruch's membrane lies beneath the retina and the adjacent retina pigment epithelium layer. Fat accumulates in Bruch's membrane with age and may contribute to the formation of drusen.
Drusen can occur in two forms. One form comprises hard, small (less than about 60 micrometers in diameter) drusen which do not increase with age and which do not predispose to macular degeneration. Another form comprises soft, large (more than about 63 micrometers in diameter) drusen which enlarge and become confluent with age. The soft, large drusen may predispose to macular degeneration, and are commonly seen in eyes of people with advanced macular degeneration in at least their other eye.
Drusen may be metabolic waste products from various layers of the retina such as from the retina, retina pigment epithelium, and choriocapillaris. Drusen may be yellow, white, gray, refractile, and/or pink. Drusen may be small, medium or large in size. Drusen may be regular or irregular, or symmetrical or asymmetrical in shape. A patient who has drusen and who suffers complications in one eye may suffer no complications in the other eye. Complications may comprise one or more conditions selected from the group consisting of retina pigment epithelium atrophy, choroid neovascularization, retina detachment serous, and retina detachment hemorrhagic. Drusen may affect contrast sensitivity, and may reduce the eye's ability to see adequately to allow a person to read in dim light or to see sufficient detail to permit a person to drive an automobile safely at night.
Not all these manifestations are needed for AMD to be considered present, and drusen alone are not directly associated with vision loss. The amount of opthalmoscopically or photographically identifiable drusen increases with age. Most definitions of AMD include drusen as a requisite because of the association of drusen with vision-threatening lesions of AMD such as geographic atrophy, retinal pigment epithelial detachment and subretinal neovascularization.
While the exact causes of macular degeneration are not known, contributing factors have been identified. The collective result of the contributing factors is a disturbance between the photoreceptor cells and the tissues under the retina which nourish the photoreceptor cells, including the retinal pigment epithelium, which directly underlies and supports the photoreceptor cells, and the choroid, which underlies and nourishes the retinal pigment epithelium.
The retina and macula may be subjected to oxidative damage by oxidants such as free-radicals and singlet oxygen, 1 O 2 . The macula contains polyunsaturated fatty acids and is exposed to light, including in the visible and near ultraviolet light spectrum high-energy blue light, which can photosensitize the conversion of triplet oxygen to singlet oxygen, an oxidizing agent capable of damaging the polyunsaturated fatty acids, DNA, proteins, lipids, and carbohydrates in the macula. Reaction products resulting from oxidative interactions between components of the retina and oxidizing agents may accumulate in the retinal pigment epithelium and contribute to macular degeneration. Certain antioxidant nutrients may reduce the risk of developing macular degeneration by reducing the formation of radicals and reactive oxygen by decomposition of hydrogen peroxide without generating radicals, by quenching active singlet oxygen, and by trapping and quenching radicals before they reach a cellular target.
Another factor which may be involved in the pathology of macular degeneration comprises an elevated serum concentration of low density cholesterol lipoprotein (LDL). Low density lipoprotein cholesterol can be oxidized by an oxidizing agent to form oxidized LDL, which is found in atherosclerotic plaques. These oxidized products may accumulate as deposits in healthy retinal pigment epithelium and cause necrosis or death of functioning tissue. LDL cholesterol may also form atherosclerotic plaques in the blood vessels of the retinal and subretinal tissue, inducing hypoxia in the tissue, resulting in neovascularization. Postmenopausal women given unopposed estrogen replacement therapy can have a reduced risk of neovascular age-related macular degeneration. Estrogen can increase the amount of high density lipoprotein cholesterol (HDL) in the blood, which may produce changes in the transport and metabolism of lipid-soluble antioxidants, and limit the accumulation of oxidized LDL cholesterol in the retinal and subretinal tissues and blood vessels.
A contributing and indicating factor of advanced macular degeneration is neovascularization of the choroid tissue underlying the photoreceptor cells in the macula. Healthy mature ocular vasculature is normally quiescent and exists in a state of homeostasis in which a balance is maintained between positive and negative mediators of angiogenisis in development of new vasculature. Macular degeneration, particularly in its advanced stages, is characterized by the pathological growth of new blood vessels in the choroid underlying the macula. Angiogenic blood vessels in the subretinal choroid can leak vision obscuring fluids, leading to blindness.
Angiogenisis in the choroid can be induced by the presence of cytokine growth factors such as basic fibroblast growth factor (bFGF). Hypoxia of retinal cells may induce the expression of such growth factors, wherein the hypoxia may be induced by cellular debris or drusen accumulated in the retinal pigment epithelium, by oxidative damage of retinal and subretinal tissue, or by deposits of oxidized LDL cholesterol.
Existing retinal and subretinal vascular endothelial cells can be activated by interaction of the cytokine growth factors, such as bFGF, with tyrosine kinase mediated receptors of the endothelial cells. The activated endothelial cells can increase in cellular proliferation and express several molecular agents, such as the integrin α v β 3 , adhesion molecules, and proteolytic enzymes, which enable newly developed endothelial cells to extend through the surrounding tissue. The newly extended endothelial cells can form into vascular cords and eventually differentiate into mature blood vessels.
Currently, no treatment has been shown to be of benefit to the majority of people who have AMD. There is no therapy that can significantly slow the degenerative progression of macular degeneration, or which can inhibit or substantially reduce the rate of subretinal neovascularization and proliferation of neovascular tissue in the choroids under the macula of the eye. Most experimental forms of treatment address the wet form of AMD, and target specifically neovascularization. Laser photocoagulation of the subretinal neovascular membranes that occur in 10-15% of affected patients can benefit individuals with macular degeneration who develop acute, extrafoveal choroidal neovascularization. For dry AMD, high daily doses of antioxidants such vitamin C (500 mg), vitamin E (400 IU), beta carotene (15 mg), as well as zinc oxide (80 mg; high concentrations of zinc occur in ocular tissues, particularly the retina, pigment epithelium and choroid) may modestly reduce risk of progression of those who have intermediate-sized drusen, large drusen, or non-central geographic atrophy, or advanced macular degeneration in one eye.
A number of techniques have been disclosed for administration of drugs to the eye including the posterior region of the eye. For example, U.S. Pat. No. 5,707,643 relates to a biodegradable scleral plug that is inserted through an incision in the sclera into the vitreous body. For administration of a drug to the eye, the plug releases a drug into the vitreous body for treating the retina by diffusion through the vitreous body.
Another technique for administration of a drug to the eye is disclosed in U.S. Pat. No. 5,443,505 which discloses implants which can be placed in the suprachoroidal space over an avascular region of the eye such as the pars plana or a surgically induced avascular region. Another embodiment involves forming a partial thickness scleral flap over an avascular region, inserting an implant onto the remaining scleral bed, optionally with holes therein, and suturing closed the flap. The drug can diffuse into the vitreous region and the intraocular structure.
Another delivery approach for administration of a drug to the eye is direct injection. For the posterior segment of the eye, an intravitreal injection has been used to deliver drugs into the vitreous body. In this regard, U.S. Pat. No. 5,632,984 relates to a treatment of macular degeneration with various drugs by intraocular injection. For administration of a drug to the eye, drugs are preferably injected as microcapsules. Intraocular injection into the posterior segment of the eye can allow diffusion of the drug throughout the vitreous, the entire retina, the choroid and the opposing sclera. Additionally, U.S. Pat. No. 5,770,589 relates to treating macular degeneration by intravitreally injecting an anti-inflammatory into the vitreous humor for administration of a drug to the eye. Injections can be administered through the pars plana in order to minimize the damage to the eye while drug is delivered to the posterior segment.
Another delivery approach is by surgical procedure. For example, U.S. Pat. No. 5,767,079 relates to the treatment of ophthalmic disorders including macular holes and macular degeneration, by administration of TGF-β for example by placing an effective amount of the growth factor on the ophthalmic abnormality. In treating the macula and retina, for administration of a drug to the eye a surgical procedure involving a core vitrectomy or a complete pars plana vitrectomy is performed before the growth factor can be directly applied, presumably by administration to the sclera on the anterior segment of the eye at an avascular region or by administration to the sclera behind the retina via a surgical procedure through the vitreous body, retina, and choroids, a dramatic, highly invasive, technique usually suitable only where partial vision loss has already occurred or was imminently threatened.
Another delivery approach for administration of a drug to the eye is by use of a device and a cannula. For example, U.S. Pat. No. 5,273,530 relates to the intraretinal delivery and withdrawal of samples and a device therefor. Unlike direct intraocular injection techniques, the method disclosed in this patent avoids the use of a pars plana incision and instead uses an insertion path around the exterior of the orbit. The device, having a curved handle and a tip with collar, allows a cannula to be inserted through the posterior sclera and down into the subretinal space without passing through the vitreous body. The collar is stated to regulate the penetration to the desired depth. The device is taught to be adjustable to any part of the eye including the scleral area, the choroidal area, the subretinal area, the retinal area and the vitreous area.
Another delivery approach for administration of a drug to the eye is by intrascleral injection. For example, U.S. Pat. No. 6,397,849, the contents of which is hereby incorporated by reference in its entirety, discloses a method of intrascleral injection which comprises injecting into the scleral layer of an eye through a location on the exterior surface of the sclera which overlies retinal tissue an effective amount of a therapeutic or diagnostic material. Depending on the injection conditions, the material can form a depot within the scleral layer and diffuse into the underlying tissue layers such as the choroid and/or retina, and/or the material can be propelled through the scleral layer and into the underlying layers. Because the sclera moves with the entire eye including the retina, the site of deposit on the sclera remains constant relative to a point on the underlying retina, even as the eye moves within the eye socket to permit site specific delivery by depositing material into the sclera at a site overlying the macula, thereby allowing material to be delivered to the macula and surrounding tissues. The injection procedure employs a cannula or needle as well as needle-less particle/solution techniques. In a preferred embodiment, a cannula is inserted into the sclera in a rotational direction relative to the eye and not orthogonal to the surface of the sclera.
Another delivery approach for administration of a drug to the eye is disclosed in U.S. Pat. No. 6,299,895 which discloses a method for delivering a biologically active molecule to the eye comprising implanting a capsule periocularly in the sub-Tenon's space, the capsule comprising a core containing a cellular source of the biologically active molecule and a surrounding biocompatible jacket, the jacket permitting diffusion of the biologically active molecule into the eye, wherein the dosage of the biologically active molecule delivered is between 50 pg and 1000 ng per eye per patient per day. The biologically active molecule can be an anti-angiogenic factor, and a second biologically active molecule or peptide can be co-delivered from the capsule to the eye. The method is disclosed to be useful treating ophthalmic disorders including macular degeneration.
Other delivery approaches for administration of a drug to the eye which can be useful with compositions of the current invention are well known in the art. For example, U.S. Pat. No. 5,399,163 discloses a method of providing a jet injection by pressurizing a fluid injectant; U.S. Pat. No. 5,383,851 discloses a needleless injection device; U.S. Pat. No. 5,312,335 discloses a needleless injection system; U.S. Pat. No. 5,064,413 discloses an injection device; U.S. Pat. No. 4,941,880 discloses an ampule for non-invasive injecting of a medication; U.S. Pat. No. 4,790,824 discloses a non-invasive hypodermic injection device; U.S. Pat. No. 4,596,556 discloses a pressure-operated hypodermic injection apparatus; U.S. Pat. No. 4,487,603 discloses an implantable micro-infusion pump for dispensing medication at a controlled rate; U.S. Pat. No. 4,486,194 discloses a therapeutic device for administering medicants through the skin; U.S. Pat. No. 4,447,233 discloses a medication infusion pump for delivering medication at a precise infusion rate; U.S. Pat. No. 4,447,224 discloses a variable flow implantable infusion apparatus for continuous drug delivery; U.S. Pat. No. 4,439,196 discloses an osmotic drug delivery system having multi-chamber compartments; and U.S. Pat. No. 4,475,196 discloses an osmotic drug delivery system.
SUMMARY OF THE INVENTION
In accordance with the present invention a conjugate, drug delivery construct, or fusion protein comprising a therapeutically active agent is provided whereby the active agent may be delivered across a cell wall membrane, the conjugate or fusion protein comprising at least a transport subdomain(s) or moiety(ies) (i.e., transport agent region) in addition to an active agent moiety(ies) (i.e., active agent region). More particularly, as discussed herein, in accordance with the present invention a conjugate or fusion protein is provided wherein the therapeutically active agent is one able to facilitate (for facilitating) axon (or dendrite, or neurite) growth (e.g. regeneration) i.e. a conjugate or fusion protein in the form of a conjugate Rho antagonist.
The present invention also relates to methods of treatment of macular degeneration associated with subretinal neovascularization and a proliferation of neovascular tissue in the eye of a mammalian host, and to methods of inhibiting or substantially reducing the rate of subretinal neovascularization and proliferation of neovascular tissue in the eye associated with macular degeneration, and to pharmaceutical compositions useful therein comprising a cell-permeable fusion protein conjugate comprising a polypeptidic cell-membrane transport agent and an active agent having ADP-ribosyl transferase activity.
The present invention also relates to methods of treatment of diabetic neuropathy, especially diabetic retinopathy associated with the damage to blood vessels caused by diabetes that leads to macular edema in the eye and neovascularization, and to methods of inhibiting or substantially reducing the rate of blood vessel damage and proliferation of neovascular tissue in the eye associated with diabetic neuropathy, and to pharmaceutical compositions useful therein comprising a cell-permeable fusion protein conjugate comprising a polypeptidic cell-membrane transport agent and an active agent having ADP-ribosyl transferase activity
The present invention also relates to methods of treatment of retinitis pigmentosa, a group of hereditary retinal diseases associated with degeneration of the retinal neurons, specifically the photoreceptor neurons (also referred to as photoreceptor cells), and to method of inhibiting photoreceptor degeneration in the eye of a mammalian host, and to methods of inhibiting or substantially reducing the rate of photoreceptor cell death associated with retinitis pigmentosa, and to pharmaceutical compositions useful therein comprising a cell-permeable fusion protein conjugate comprising a polypeptidic cell-membrane transport agent and an active agent having ADP-ribosyl transferase activity.
The present invention in particular relates to a means of intracellular delivery of C3 protein (e.g. C3 itself or other active analogues such as C3-like transferases—see below) or other Rho antagonists to repair damage in the nervous system, to prevent ischemic cell death, and to treat various disease where the inactivation of Rho is required. The means of delivery may take the form of chimeric (i.e. conjugate) C3-like Rho antagonists. These conjugate antagonists provide a significant improvement over C3 compounds (alone) because they are 3 to 4 orders of magnitude more potent with respect to the stimulation of axon growth on inhibitory substrates than recombinant C3 alone. Examples of these Rho antagonists have been made as recombinant proteins created to facilitate penetration of the cell membrane (i.e. to enhance cell uptake of the antagonists), improve dose-response when applied to neurons to stimulate growth on growth inhibitory substrates, and to inactivate Rho. Examples of these conjugate Rho antagonists are described below in relation to the designations C3APL, C3APLT, C3APS, C3-TL, C3-TS, C3Basic1, C3Basic2 and C3Basic3.
The present invention in accordance with an aspect thereof provides a drug delivery construct or conjugate [e.g. able to (for) suppress(ing) the inhibition of neuronal axon growth at a central nervous system (CNS) lesion site or a peripheral nervous system (PNS) lesion site] comprising at least one transport agent region and an active agent region not naturally associated with the active agent region, wherein the transport agent region is able to facilitate (i.e. facilitates) the uptake of the active agent region into a mammalian (i.e. human or animal) tissue or cell, and wherein the active agent region is an active therapeutic agent region able (i.e. has the capacity or capability) to facilitate axon growth for example on growth inhibitory substrates (e.g. regeneration), either in vivo (in a mammal (e.g., human or animal)) or in vitro (in cell culture), including a derivative or homologue thereof (i.e. pharmaceutically acceptable chemical equivalents thereof—pharmaceutically acceptable derivative or homologue).
In accordance with the present invention the active agent region may be an ADP-ribosyl transferase C3 region. In accordance with the present invention the ADP-ribosyl transferase C3 may be selected from the group consisting of ADP-ribosyl transferase (e.g., ADP-ribosyl transferase C3) derived from Clostridium botulinum and a recombinant ADP-ribosyl transferase (e.g., recombinant ADP-ribosyl transferase C3) that includes the entire C3 coding region, or only a part (fragment) of the C3 coding region that retains the ADP-ribosyl transferase activity, or analogues (derivatives) of C3 that retains the ADP-ribosyl transferase activity, or enough of the C3 coding region to be able to effectively inactivate Rho. The active agent could also be selected from other known ADP-ribosyl transferases that act on Rho (Wilde et al. 2000 J. Biol. Chem. 275-16478-16483; Wilde et al 2001. J. Biol. Chem. 276:9537-9542).
In accordance with another aspect the present invention provides a drug conjugate consisting of a transport polypeptide moiety (e.g. rich in basic amino acids e.g. arginine, lysine, histidine, asparagine, glutamine) covalently linked to an active cargo moiety (e.g. by a peptide bond or a labile bond (i.e. a bond readily cleavable or subject to chemical change in the interior target cell environment)) wherein the transport polypeptide moiety is able to or has the capability to facilitate(s) the uptake of the active cargo moiety into a mammalian (e.g. human or animal) tissue or cell (for example, a transport subdomain of HIV (e.g., HIV-1) Tat protein, a homeoprotein transport sequence (referred also as a transport homeoprotein) (e.g. the homeodomain of antennapedia), a Histidine tag (ranging in length from 4 to 30 histidine repeat) or a variation derivative or homologue thereof, (i.e. pharmaceutically acceptable chemical equivalents thereof)) [by a receptor independent process] and wherein the active cargo moiety is an active therapeutic moiety able (i.e. has the capacity or capability) to facilitate (i.e. for facilitating) axon growth (e.g. regeneration, budding) or neuroprotection (prevention of cell death) either in vivo (in a mammal (e.g., human or animal)) or in vitro (in cell culture).
In accordance with the present invention the transport polypeptide moiety may be selected from the group consisting of SEQ ID NO.: 48, a transport subdomain of HIV (e.g., HIV-1) Tat protein such as for example SEQ ID NO.: 46, SEQ ID NO.:47, a homeodomain of antennapedia, such as for example SEQ ID NO.: 44, SEQ ID NO.: 45, a Histidine tag and a functional derivative and analogues thereof (e.g., SEQ ID NO.: 21, SEQ ID NO.: 26, SEQ ID NO.: 31) [i.e. by the addition of polyamine, or any random sequence enriched in basic amino acids]—[i.e. pharmaceutically acceptable chemical equivalents thereof] and wherein the active cargo moiety is selected from the group consisting of C3 protein able (i.e. has the capacity or capability) to facilitate (i.e. for facilitating) axon growth (e.g. regeneration, budding) or neuroprotection (prevention of cell death) either in vivo (in a mammal (e.g., human or animal)) or in vitro (in cell culture).
In accordance with the present invention the C3 protein may be selected from the group consisting of ADP-ribosyl transferase C3 and ADP-ribosyl transferase C3 analogue. In accordance with the present invention the ADP-ribosyl transferase C3 may be selected from the group consisting of ADP-ribosyl transferase (e.g., ADP-ribosyl transferase C3) derived from Clostridium botulinum and a recombinant ADP-ribosyl transferase (e.g., recombinant ADP-ribosyl transferase C3). The ADP-ribosyl transferase may be a protein with a C3-like activity, such as that derived from Staphylococcus aureus (Wilde et al 2001. J. Biol. Chem. 276:9537-9542). The ADP-ribosyl transferase may be any other transferase that acts to inactivate RhoA, RhoB and/or RhoC such as those derived from Clostridium limosum , and Bacillus cereus (Wilde et al 2000. J. Biol. Chem. 275:16478-16483). In accordance with the present invention the transport polypeptide moiety may include an active contiguous amino acid sequence as described herein.
In accordance with an additional aspect the present invention provides a fusion protein (polypeptide) [e.g. able to (for) suppress(ing) the inhibition of neuronal axon growth at a central nervous system (CNS) lesion site or a peripheral nervous system (PNS) lesion site] consisting of a carboxy terminal active cargo moiety and an amino terminal transport moiety, wherein the amino terminal transport moiety is selected from the group consisting of a transport subdomain of HIV (e.g., HIV-1) Tat protein, homeoprotein transport sequence (referred also as a transport homeoprotein) (e.g. the homeodomain of antennapedia), a Histidine tag and a functional derivatives and analogues thereof (i.e. pharmaceutically acceptable chemical equivalents thereof) and wherein the active cargo moiety consists of a C3 protein.
The present invention in particular provides a fusion protein (polypeptide) (e.g. able to (for) suppressing the inhibition of neuronal axon growth at a central nervous system (CNS) lesion site or a peripheral nervous system (PNS) lesion site) consisting of a carboxy terminal active cargo moiety and an amino terminal transport moiety, wherein the amino terminal transport moiety consists of the homeodomain of antennapedia and the active cargo moiety consists of a C3 protein (i.e. as described herein). The present invention also in particular provides a fusion protein (polypeptide) (e.g. able to (for) suppressing the inhibition of neuronal axon growth at a central nervous system (CNS) lesion site or a peripheral nervous system (PNS) lesion site) consisting of a carboxy terminal active cargo moiety and an amino terminal transport moiety, wherein the amino terminal transport moiety consists of a transport subdomain of (e.g., HIV-1) Tat protein and the active cargo moiety consists of a C3 protein (i.e. as described herein).
In accordance with the present invention the C3 protein may be selected from the group consisting of ADP-ribosyl transferase C3 and ADP-ribosyl transferase C3 analogues. In accordance with the present invention the ADP-ribosyl transferase C3 is selected from the group consisting of ADP-ribosyl transferase (e.g., ADP-ribosyl transferase C3) derived from Clostridium botulinum and a recombinant ADP-ribosyl transferase (e.g., recombinant ADP-ribosyl transferase C3).
In accordance with an additional aspect the present invention provides a fusion protein (polypeptide) [e.g. able to (for) suppress(ing) the inhibition of neuronal axon growth at a central nervous system (CNS) lesion site or a peripheral nervous system (PNS) lesion site] consisting of an amino terminal active cargo moiety and a carboxy terminal transport moiety, wherein the carboxy terminal transport moiety is selected from the group consisting of a transport subdomain of HIV Tat protein, a homeoprotein transport sequence (referred also as a transport homeoprotein) (e.g. the homeodomain of antennapedia), a Histidine tag and a functional derivatives and analogues thereof (i.e. pharmaceutically acceptable chemical equivalents thereof) and wherein the active cargo moiety consists of a C3 protein.
The present invention in particular provides a fusion protein (polypeptide) (e.g. able to (for) suppressing the inhibition of neuronal axon growth at a central nervous system (CNS) lesion site or a peripheral nervous system (PNS) lesion site) consisting of an amino terminal active cargo moiety and a carboxy terminal transport moiety, wherein the carboxy terminal transport moiety consists of the homeodomain of antennapedia and the active cargo moiety consists of a C3 protein (i.e. as described herein).
The present invention also in particular provides a fusion protein (polypeptide) (e.g. able to (for) suppressing the inhibition of neuronal axon growth at a central nervous system (CNS) lesion site or a peripheral nervous system (PNS) lesion site) consisting of an amino terminal active cargo moiety and a carboxy terminal transport moiety, wherein the carboxy terminal transport moiety consists of a transport subdomain of HIV Tat protein and the active cargo moiety consists of a C3 protein (i.e. as described herein).
In accordance with the present invention the C3 protein may be selected from the group consisting of ADP-ribosyl transferase C3 and ADP-ribosyl transferase C3 analogues. In accordance with the present invention the ADP-ribosyl transferase C3 is selected from the group consisting of ADP-ribosyl transferase C3 derived from Clostridium botulinum and a recombinant ADP-ribosyl transferase C3.
The present invention in a further aspect provides for the use of a member selected from the group consisting of a drug delivery construct as described herein, a drug conjugate as described herein and a fusion protein (polypeptide) as described herein (e.g. including pharmaceutically acceptable chemical equivalents thereof) for suppressing the inhibition of neuronal axon growth.
The present invention in a further aspect relates to a pharmaceutical composition (e.g. for suppressing the inhibition of neuronal axon growth), the pharmaceutical composition comprising a pharmaceutically acceptable diluent or carrier and an effective amount of an active member selected from the group consisting of a drug delivery construct as described herein, a drug conjugate as described herein, and a fusion protein (polypeptide) as described herein (e.g. including pharmaceutically acceptable chemical equivalents thereof).
The present invention further provides for the use of a member selected from the group consisting of a drug delivery construct as described herein, a drug conjugate as described herein, and a fusion protein (polypeptide) as described herein (e.g. including pharmaceutically acceptable chemical equivalents thereof) for the manufacture of a pharmaceutical composition (e.g. for suppressing the inhibition of neuronal axon growth).
The present invention also relates to a method for preparing a drug delivery construct, a conjugate or fusion protein (polypeptide) as defined above comprising
cultivating a host cell (bacterial or eukaryotic) under conditions which provide for the expression of the drug delivery construct, the conjugate or fusion protein (polypeptide) within the cell; (the drug delivery construct, conjugate or fusion protein (polypeptide), could also be expressed to be produced in an animals, such as, for example, the production of recombinant proteins in the milk of farm animals) and,
recovering the drug delivery construct, conjugate or fusion protein (polypeptide) by a purification step.
The purification of the drug delivery construct, conjugate or fusion protein (polypeptide) may be done by affinity methods, ion exchange chromatography, size exclusion chromatography, hydrophobicity or any other purification technique typically used for protein purification. Preferably, the purification step would be performed under non-denaturating conditions. On the other hand, if a denaturating step is required, the protein may be renatured using techniques known in the art.
The present invention also relates to the expression of the drug delivery construct, conjugate or fusion protein (polypeptide) in a mammalian cell, which when used with a signal sequence, will allow expression and secretion of the fusion protein into the extracellular milieu. Other system of expression (yeast cells, bacterial cells, insect cells, etc.) may be suitable to express (produce) the drug delivery construct, conjugate or fusion protein (polypeptide) of the present invention as discussed herein.
The present invention in particular provides a fusion protein (polypeptide) selected from the group consisting of C3APL (SEQ ID NO.: 4), C3APLT (SEQ ID NO.: 37), C3APS (SEQ ID NO.:6), C3-TL (SEQ ID NO.:14), C3-TS (SEQ ID NO.: 18), C3Basic1 (SEQ ID NO.:25), C3Basic2 (SEQ ID NO.: 30), C3Basic3 (SEQ ID NO.:35), SEQ ID NO.: 20, and SEQ ID NO.: 43 and pharmaceutically acceptable chemical equivalents thereof.
In accordance with an additional aspect, the present invention provides a pharmaceutical composition comprising a polypeptide selected from the group consisting of C3APL (SEQ ID NO.:4), C3APLT (SEQ ID NO.:37), C3APS (SEQ ID NO.:6), C3-TL (SEQ ID NO.: 14), C3-TS (SEQ ID NO.:18), C3Basic1 (SEQ ID NO.:25), C3Basic2 (SEQ ID NO.:30), C3Basic3 (SEQ ID NO.:35), SEQ ID NO.: 20 and SEQ ID NO.: 43, and a pharmaceutically acceptable carrier.
In accordance with the present invention, the pharmaceutical composition may further comprise a biological adhesive, such as, for example, fibrin (fibrin glue).
In a further aspect the present invention provides a pharmaceutical composition comprising a polypeptide comprising at least one (one or more) transport agent region and an active agent region, said active agent region being selected from the group consisting of ADP-ribosyl transferase C3 and ADP-ribosyl transferase C3 analogues, and a pharmaceutically acceptable carrier.
In accordance with the present invention, the transport agent region may be at the carboxy-terminal end of said polypeptide and the active agent region may be at the amino terminal end of said polypeptide.
In accordance with the present invention, the pharmaceutical composition may further comprise a biological adhesive, such as, for example, fibrin (fibrin glue).
In an additional aspect, the present invention provides a polypeptide comprising at least one (one or more) transport agent region and an active agent region, said active agent region being selected from the group consisting of ADP-ribosyl transferase C3 and ADP-ribosyl transferase C3 analogues (wherein the transport agent region is able to facilitate the uptake of the active agent region into (inside the cell or in the cell membrane) a cell).
In an additional aspect, the present invention provides a polypeptide consisting of a carboxy-terminal active agent moiety and an amino-terminal transport moiety region (wherein the transport agent region is able to facilitate the uptake of the active agent region into (inside the cell or in the cell membrane) a cell) and wherein said carboxy-terminal active agent moiety may be selected from the group consisting of ADP-ribosyl transferase C3 and ADP-ribosyl transferase C3 analogues thereof.
In accordance with the present invention, the carboxy-terminal transport moiety region may be selected from the group consisting of a basic amino acid rich region and a proline rich region.
In a further aspect, the present invention relates to a polypeptide consisting of an amino-terminal active agent moiety and a carboxy-terminal transport moiety region, wherein said amino-terminal active agent moiety may be selected from the group consisting of ADP-ribosyl transferase C3 and ADP-ribosyl transferase C3 analogues thereof.
In accordance with the present invention, the carboxy-terminal transport moiety region may be selected from the group consisting of a basic amino acid rich region and a proline rich region.
In yet a further aspect, the present invention relates to a conjugate comprising at least one transport agent region (including one, two, three or more transport agent region) and an active agent region, said active agent region being selected from the group consisting of ADP-ribosyl transferase C3 and ADP-ribosyl transferase C3 analogues, wherein said transport agent region is covalently linked to said active agent region.
In accordance with the present invention, the transport agent region may be cross-linked (e.g., chemically cross-linked, UV cross-linked) to the active agent region (C3-like proteins of the present invention and analogues thereof).
In accordance with the present invention, the transport agent region may be fused to ADP-ribosyl transferase C3 and ADP-ribosyl transferase C3 analogues according to recombinant DNA technology (e.g., cloning the DNA sequence of the transport agent region in frame with the DNA sequence of the ADP-ribosyl transferase C3 or an ADP-ribosyl transferase C3 analogue comprising or not a spacer DNA sequence (multiple cloning site, linker) or any other DNA sequence that would not interfere with the activity of the C3-like protein once expressed).
In an additional aspect, the present invention relates to the use of a polypeptide selected from the group consisting of C3APL (SEQ ID NO.: 4), C3APLT (SEQ ID NO.:37), C3APS (SEQ ID NO.:6), C3-TL (SEQ ID NO.: 14), C3-TS (SEQ ID NO.:18), C3Basic1 (SEQ ID NO.:25), C3Basic2 (SEQ ID NO.:30), C3Basic3 (SEQ ID NO.:35), SEQ ID NO.: 20 and SEQ ID NO.: 43, for the manufacture of a pharmaceutical composition.
In other aspects, the present invention relates to the use of a polypeptide comprising at least one (one or more) transport agent region and an active agent region, for the manufacture of a pharmaceutical composition, or to facilitate (for facilitating) axon growth or for treating (in the treatment of) nerve injury (e.g., nerve injury arising from traumatic nerve injury or nerve injury caused by disease), or for preventing (diminishing, inhibiting (partially or totally)) cell apoptosis (cell death, such as following ischemia in the CNS), or for suppressing (diminishing) the inhibition of neuronal axon growth, or for the treatment of ischemic damage related to stroke, or for suppressing (diminishing) Rho activity, or to regenerate (for regenerating) injured axon (helping injured axon to recover, partially or totally, their function), or to help (for helping) neurons to make new connections (developing axon, dendrite, neurite) with other (surrounding) cells (neuronal cells), in a mammal, (e.g., human, animal), wherein said active agent region being selected from the group consisting of ADP-ribosyl transferase C3 and ADP-ribosyl transferase C3 analogues.
A cell-permeable fusion protein conjugate comprising a polypeptidic cell-membrane transport agent covalently linked to an active agent having ADP-ribosyl transferase activity can be used to treat diseases of the eye selected from the group consisting of macular degeneration (wet AMD and dry AMD), retinitis pigmentosa, Stargardt's Disease, diabetic retinopathy, hypertensive retinopathy, and occlusive retinopathy and related diseases of the retina. Cell permeable fusion protein Rho antagonists are expected to prevent both neovascularization and photoreceptor cell death, unlike other treatments that only target the neovascularization present in the disease. This can be particularly advantageous for the treatment of wet macular degeneration.
In one aspect, a therapeutically effective amount of a pharmaceutical composition comprising a cell-permeable fusion protein conjugate comprising a polypeptidic cell-membrane transport moiety and a Clostridium botulinum C3 exotransferase unit, or a functional analog thereof, for example a fusion protein such as C3APLT, can exhibit anti-angiogenic activity and is useful in the treatment of a disease of the eye selected from the group consisting of macular degeneration, retinitis pigmentosa, Stargardt's Disease, diabetic retinopathy, hypertensive retinopathy, and occlusive retinopathy. A therapeutically effective amount can be about 1 microgram per milliliter to about 10 micrograms per milliliter or from about 10 micrograms to about 50 micrograms per milliliter.
Administration of a pharmaceutical composition of this invention can be selected from the group consisting of intrarticular, intraocular, intranasal, intraneural, intradermal, intraosteal, sublingual, oral, topical, intravesical, intrathecal, intravenous, intraperitoneal, intracranial, intramuscular, subcutaneous, inhalation, atomization and inhalation, application directly into a tissue of or proximal to the eye or CNS, application directly into a disease site especially into a blood vessel that supplies blood to the retina or to a cell or tissue or structure of an eye, application directly on or into the margins remaining after an operative resection such as a resuction of a tumor, enteral, enteral together with a gastroscopic procedure, and ECRP.
Administration of a pharmaceutical composition of this invention is preferably by injection, such as by injection into an eye, preferably into a blood vessel that supplies blood to the eye or by microinjection into the macula by first penetrating the sclera, by topical application such as to a tissue of the eye such as the cornea or sclera, or by implantation such as by controlled release from a depot or implant comprising a fusion protein of this invention optionally in the presence of a pharmaceutically acceptable matrix or pharmaceutically acceptable carrier, which depot or implant is located proximal to the tissue of the eye, preferably proximal to or embedded into tissue comprising the posterior portion of the eye. A therapeutically effective amount of a fusion protein of this invention can be delivered to the choroid and retina proximal to the macula of the eye to prevent (such as in a prophylactic treatment) or retard the growth of blood vessels that lead to macular degeneration in the eye.
In one aspect, therapeutic compositions of this invention can be administered to the eye by a number of techniques including by use of medical devices and methods of administration known in the art, such as for example those described in U.S. Pat. Nos. 6,397,849; 6,299,895; 5,770,589; 5,767,079; 5,707,643; 5,632,984; 5,443,505; 5,399,163; 5,383,851; 5,273,530; 5,064,413; 4,941,880; 4,790,824; 4,596,556; 4,487,603; 4,486,194; 4,475,196; 4,447,224; 4,447,233; and 4,439,196 cited hereinabove, which patents are incorporated herein by reference. Many other methods of administration such as a single or multiple implant comprising a poorly water soluble and/or biodegradable matrix composition for controlled release of a protein of this invention, an implantable hydrogel matrix which can be biodegradable and comprising a drug, an injectable delivery system such as a liposome suspension comprising a protein of this invention entrapped in the interior and/or membrane portion of the liposome which liposome is suspended in an aqueous medium, injection methods such as comprising a needleless syringe or cannula or needle and syringe, nanoparticulate implantation methods comprising a protein of this invention and a poorly water soluble and biodegradable carrier, and delivery routes that are applicable to administer a drug to the eye and to blood vessels that feed blood to the eye can be used with the compositions of this invention.
The fusion proteins and pharmaceutical compositions of fusion proteins of the present invention can be delivered by a variety of techniques to the macula region of the eye, preferably to the posterior segment of the eye proximal to the macula. Examples of such techniques include:
a) use of a sterile, pharmaceutically acceptable biodegradable scleral plug which comprises a fusion protein of this invention and optionally a pharmaceutically acceptable biodegradable matrix such as a polylactic acid or polyglycolic acid or a copolymer of lactic acid and glycolic acid, which plug can be inserted into the eye via an incision in the sclera; b) use of an implant comprising a fusion protein of this invention and optionally a pharmaceutically acceptable biodegradable matrix wherein the sclera is cut to expose the suprachoroid and wherein the implant is placed into a suprachoroidal space form which implant the fusion protein is released for example into the vitreous region of the eye; c) use of intravitreal injection into the vitreous body of a pharmaceutical composition comprising a fusion protein of this invention and a sterile aqueous carrier, wherein the fusion protein comprises a submicron-to about 4 micron-sized pharmaceutically acceptable particulate composition; d) injection or infusion via a flexible cannula that can be inserted through the posterior sclera and down into the subretinal space at the posterior region of the eye; and e) by injection of a pharmaceutical composition comprising a fusion protein of this invention and a pharmaceutically acceptable carrier into an avascular region of the sclera to form a depot comprising a fusion protein of this invention within the scleral layer and from which the fusion protein can diffuse to the macula, choroid layer, and/or retina.
In one aspect, a pharmaceutical composition of this invention can comprise a pharmaceutically acceptable carrier selected from the group consisting of poly(ethylene-co-vinyl acetate), PVA, partially hydrolyzed poly(ethylene-co-vinyl acetate), poly(ethylene-co-vinyl acetate-co-vinyl alcohol), a cross-linked poly(ethylene-co-vinyl acetate), a cross-linked partially hydrolyzed poly(ethylene-co-vinyl acetate), a cross-linked poly(ethylene-co-vinyl acetate-co-vinyl alcohol), poly-D,L-lactic acid, poly-L-lactic acid, polyglycolic acid, PGA, copolymers of lactic acid and glycolic acid, polycaprolactone, polyvalerolactone, poly(anhydrides), copolymers of polycaprolactone with polyethylene glycol, copolymers of polylactic acid with polyethylene glycol, polyethylene glycol; fibrin, Gelfoam (which is a water-insoluble, off-white, nonelastic, porous, pliable gel foam prepared from purified gelatin such as pork skin gelatin and water for injection), and combinations and blends thereof. Copolymers can comprise from about 1% to about 99% by weight of a first monomer unit such as ethylene oxide and from 99% to about 1% by weight of a second monomer unit such as propylene oxide. Blends of a first polymer such as gelatin and a second polymer such as poly-L-lactic acid or polyglycolic acid can comprise from about 1% to about 99% by weight of the first polymer and from about 99% to about 1% of the second polymer.
A fusion protein of this invention can be prepared as a solution or as a suspension in an aqueous medium such as a buffered saline or phosphate solution in water for injection, sterilized such as by filtration through a 0.2 micron or smaller pore size filter and injected in to an implanted matrix proximal to the tissue of the eye such as in a sterile gel foam (Gelfoam) matrix which can be absorbed completely. This absorption is dependent on several factors, including the amount used, degree of saturation with blood or other fluids, and the site of use. When placed in soft tissues, Gelfoam can be absorbed completely for example in from four to six weeks, without inducing excessive scar tissue. When applied to bleeding nasal, rectal or vaginal mucosa, it can liquefy within two to five days.
In another aspect, a pharmaceutical composition of this invention comprises a pharmaceutically acceptable carrier. For example, the carrier can be selected from the group consisting of water, a pharmaceutically acceptable buffer salt, a pharmaceutically acceptable buffer solution, a pharmaceutically acceptable antioxidant such as ascorbic acid, one or more low molecular weight pharmaceutically acceptable polypeptide such as a pharmaceutically acceptable peptide comprising about 2 to about 10 amino acid residues, one or more pharmaceutically acceptable protein such as albumin, one or more pharmaceutically acceptable amino acid such as an essential-to-human amino acid, one or more pharmaceutically acceptable carbohydrate, one or more pharmaceutically acceptable acetylated or otherwise esterified carbohydrate material obtained for example by esterification with a 2 to 20 carbon pharmaceutically acceptable carboxylic acid, a non-reducing sugar, glucose, sucrose, sorbitol, trehalose, mannitol, maltodextrin, dextrins, cyclodextrin, a pharmaceutically acceptable chelating agent, EDTA which is ethylenediamine tertraacetic acid, DTPA, a chelating agent for a divalent metal ion such as zinc ion, a chelating agent for a trivalent metal ion, glutathione, pharmaceutically acceptable nonspecific serum albumin, an antibody to a growth factor, and combinations thereof.
The pharmaceutical compositions of this invention can be sterile, sterilizable, and sterilized. A preferred method of sterilization comprises filtration of a pharmaceutical composition through a 0.2 micron filter in a sterile environment. The sterile filtered composition can be filled in a vial, preferably into a sterile vial, in a unit dosage volume amount (comprising a therapeutically effective amount of fusion protein of this invention) or in an integral multiple of a unit dosage amount (e.g., as 2 unit dosage amount, 3 unit dosage amounts, 4 unit dosage amounts, et cetera), preferably under an inert atmosphere such as sterile nitrogen or argon, and the vials sealed with a pharmaceutically acceptable stopper, optionally with a crimp cap. In another aspect, pharmaceutical composition is dried by removal of water, for example the aqueous medium can be removed from each vial by a drying process such as by lyophilization or evaporation to leave a dried or dehydrated matrix comprising the fusion protein of this invention, before sealing and capping of the vial. In another aspect, the carrier can comprise a sterile or sterilizable hypertonic solution of a pharmaceutically acceptable matrix-forming material or excipient that is compatible with the fusion protein, for example, such as a pharmaceutically acceptable non-reducing carbohydrate, together with a compound or fusion protein of the invention, which hypertonic solution can be placed in a vial and dried (e.g., by lyophilization) to provide a matrix comprising the fusion protein and the matrix-forming excipient, which can be sealed in the vial with a cap. Prior to use, sterile water can be added to the vial, for example via sterile syringe or cannula, which water can dissolve the matrix to provide a solution or suspension of the fusion protein. Sufficient water can be added to provide the reconstituted solution or suspension as an isotonic solution suitable for injectable or implantable use.
The pharmaceutical compositions provided herein may be placed within containers along with packaging material which provides instructions regarding the use of such materials. Generally, such instructions will include a description of the concentration of the active agent, as well as within certain embodiments, relative amounts or identities of excipient ingredients or diluents (e.g., water, saline or PBS). In addition, it may be necessary to reconstitute the pharmaceutical composition to a pharmaceutically acceptable solution or suspension by the addition of water and optionally also with shaking or sonication.
A pharmaceutical composition of the present invention in a therapeutically effective amount (e.g., in the form of a spray or an aerosol) may be delivered via an endoscopic procedure, wherein the composition is sprayed or aerosolized inside a patient to provide a coating comprising a fusion protein of this invention on a tissue inside a patient. In another aspect, coating of a pharmaceutical composition on to a tissue proximal to an eye and preferably accessible to the chorioid of the eye can inhibit angiogenesis in the region of tissue that is coated by the pharmaceutical composition.
Optionally, the pharmaceutical composition can be packaged in a vial or syringe for injection. The vial or syringe can contain a unit dosage amount of the pharmaceutical composition or of the fusion protein in lyophilized form which can be rehydrated by the addition of water such as water for injection. Optionally, the vial can contain two or more such as three or four or five unit dosage amounts of the fusion protein or a pharmaceutical composition thereof. Optionally, the pharmaceutical composition can by lyophilized. Preferably, the pharmaceutical composition is prepared in the presence of an inert or non-oxidizing or substantially oxygen-free gas or atmosphere such as nitrogen, argon, carbon dioxide, or a fluorocarbon or fluorohydrocarbon gas.
Preferably, a pharmaceutically acceptable solution of this invention is substantially isotonic with blood.
In one aspect, the fusion protein can be formed into a sterile aqueous pharmaceutically acceptable solution or nanoparticulate suspension in the presence of a substantially water-insoluble gas such fluorocarbon such as perfluoropropane and optionally in the presence of a pharmaceutically acceptable surface active agent such as a phospholipids or a polyethylene oxide-containing surfactant such as Pluronic F68 or F108, and subjected to vibration such as ultrasonic vibration or rapid shaking, wherein microbubbles comprising the fusion protein and the gas are obtained, preferably having a mean diameter of less than about 2 microns, which microbubbles can be injected by microinjection into the blood vessel which supplies blood to the eye to deliver a therapeutically effective amount of the fusion protein to the corroid and retina proximal to the macula.
Compositions of the present invention useful for treatment of a disease of the eye selected from the group consisting of macular degeneration, retinitis pigmentosa, Stargardt's Disease, diabetic retinopathy, hypertensive retinopathy, and occlusive retinopathy may be formulated in a variety of forms. For example, in one embodiment, a pharmaceutical composition comprising a therapeutically effective amount of a cell-permeable fusion protein conjugate comprising a polypeptidic cell-membrane transport moiety and a Clostridium botulinum C3 exotransferase unit, or a functional analog thereof, can comprise a microsphere, wherein the fusion protein is blended with or embibed into a matrix comprising a pharmaceutically acceptable polymeric carrier, optionally in the presence of water (wherein the blend comprises from about 0.1% to about 50% of a fusion protein of this invention in one embodiment; alternatively, a microsphere comprising a fusion protein of this invention and a polymeric carrier can be suspended in a sterile pharmaceutically acceptable aqueous medium which is preferably isotonic with blood, in another embodiment), a pharmaceutically acceptable buffer salt, a pharmaceutically acceptable surface active agent, a pharmaceutically acceptable carbohydrate, a pharmaceutically acceptable emollient, and the like.
In another embodiment, a pharmaceutical composition of this invention can comprise a therapeutically effective amount of a cell-permeable fusion protein conjugate comprising a polypeptidic cell-membrane transport moiety and a Clostridium botulinum C3 exotransferase unit, or a functional analog thereof, and can comprise a paste, a cream, an ointment, a suspension, for example in a pharmaceutically acceptable oil such as a pharmaceutically acceptable triglyceride, and the like.
In another embodiment, a pharmaceutical composition comprising a therapeutically effective amount of a cell-permeable fusion protein conjugate comprising a polypeptidic cell-membrane transport moiety and a Clostridium botulinum C3 exotransferase unit, or a functional analog thereof, can comprise a film, for example wherein the fusion protein is blended or mixed together with a pharmaceutically acceptable carrier such as an aqueous gelatin or an aqueous protein or a polymeric carrier or a combination thereof, optionally by injection in vivo proximal to the eye or proximal to the blood vessels of the eye, optionally in the presence of a pharmaceutically acceptable cross-linking agent species which can crosslink the carrier. In one embodiment, the blend can be injected. In another embodiment, the blend can be coated into a film or laminate, optionally in the present of a film base or a support or matrix, and dried or dehydrated, optionally by the addition of heat or by lyophilization. Films can be prepared in unit dosage forms or in bulk and divided and cut into unit dosage forms.
In another embodiment, a pharmaceutical composition comprising a therapeutically effective amount of a cell-permeable fusion protein conjugate comprising a polypeptidic cell-membrane transport moiety and a Clostridium botulinum C3 exotransferase unit, or a functional analog thereof, can comprise an aerosol or sprayable or aerosolizable composition such as a suspension or solution of the fusion protein in a pharmaceutically acceptable fluid such as an aqueous solution of a buffer, optionally with a tonicity modifier; in a pharmaceutically acceptable fluid such as a supercritical or liquefied gas such as carbon dioxide or propane or a low molecular weight fluorocarbon or fluorohydrocarbon or bromofluorocarbon or chlorofluorocarbon and the like, each of which is a gas at 37° C. and ambient pressure, the composition suitable for use, for example, as an aerosol. An aerosol can be used to apply a fusion protein of this invention to the surface of a tissue proximal to the eye or into a tissue of the eye.
In another aspect, the compositions of the present invention may be formulated to contain a variety of additional compounds, in order to provide the formulated fusion protein formulations with certain physical properties (e.g., elasticity related to incorporation of a pharmaceutically acceptable plasticizing agent, a particular melting point such as about 30° C. such as by use of a polyethylene glycol, or a specified release rate which may be related to degree of crosslinking or rate of hydration in a matrix or to solubilization of a matrix, or to preferential solublization of one component of a matrix which can leave pores in the matrix through which a carrier fluid such a water can assist in transport of the fusion protein out of the matrix and into or onto a desired site such as tissue proximal to or a part of the eye in the body of a mammal.
A chemical modification of a drug molecule which can produce a lengthening of the half life of the drug molecule in bodily fluids such as blood and in tissue in vivo is PEGylation. PEGylation comprises a covalent attachment of one or more PEG-containing group to a drug molecule such as a protein or a peptide drug molecule. PEG is sometimes known referred to as poly(ethylene glycol) or polyoxyethylene or polyethylene glycol. A PEG-containing group is sometimes referred to as a “PEG” group or as a “MPEG” group where PEG refers to a hydroxy-terminated poly(ethylene glycol) or omega-hydroxy-PEG- or HO-PEG- and MPEG- refers to a methoxy-terminated poly(ethylene glycol) or omega-methoxy-PEG- or CH 3 O-PEG- or MeO-PEG-. Useful PEG and MPEG molecular weights are often from about 1000 Daltons to about 20,000 Daltons or more, preferably from about 2000 to about 20000 Daltons, and more preferably from about 5000 to about 20000 Daltons in average molecular weight. PEGylation can be achieved by chemically reacting an activated PEG or MPEG group (e.g., an MPEG that is terminally substituted with a chemically reactive functional group) with a chemically reactive site of a drug molecule (e.g., an epsilon-amino group of a lysine in a peptide or protein, a terminal amino group of a peptide or protein, a sulfhydryl group, and the like), in a suitable medium such as an aqueous buffer solution. Examples of a chemically reactive functional group on a PEG-containing reagent include an alpha-active ester of a PEG or MPEG such as an alpha-N-hydroxysuccinamidyl PEG or MPEG ester, an alpha-p-nitrophenyl PEG or MPEG ester, a vinyl sulfone group, a chlorotriazinyl group, and the like. The active functional group is usually separated from the PEG group by a spacing group which is, for example, covalently attached by a first covalent bond (e.g, amide bond formed by reaction of an active ester group with an amine; a thioether bond formed by reaction of a sulfhydryl group with a iodomethylcarbonyl group) to the PEG or MPEG group and by a second covalent bond to the chemically reactive functional group. Examples of useful spacing groups include a succinate ester spacing group, a methylenecarbonyl group, an ethylenecarbonyl group, a triazine group, an ethylenesulfonyl group, and the like. Useful pegylation reagents including low-diol pegylation reagents can be obtained commercially, for example, from Nektar Therapeutics, Huntsville, Ala. A useful family of PEG reagents and methods is described in U.S. Pat. No. 5,672,662, the disclosure of which is herein incorporated by reference. PEGylation is often associated with reduction of dose of drug and with lowered toxicity) and in some cases can interfere with generation of an immune response is PEGylation. PEGylation is believed to work by changing the size of the molecule and by changing interactions with other molecules such as antibodies by steric hindrance. PEGylation has been found to be effective for some therapeutic enzymes, peptides and antibodies.
A useful embodiment of a PEGylated fusion protein of the current invention can comprise a PEG-containing group (e.g., one or two or three or four or five molecules of 20,000 molecular weight PEG-containing group) covalently linked (e.g., by an amide bond or a thioether bond) to a fusion protein of the invention, wherein the cell permeation ability of the transport agent moiety in said PEGylated fusion protein is in the range of about 1% to about 100% (e.g., 10%, 20%, 25%, 30%, 40%, 50%, 60%, 70%, 75%, 80%, 80%, 95%, 99%) of the cell permeation ability of said transport agent in said fusion protein that is not PEGylated, and wherein the ADP-ribosyl transferase activity of said PEGylated fusion protein is in the range of about 1% to about 100% (e.g., 10%, 20%, 25%, 30%, 40%, 50%, 60%, 70%, 75%, 80%, 80%, 95%, 99%) of the ADP-ribosyl transferase activity of said fusion protein that is not PEGylated when the properties of the PEGylated fusion protein and the corresponding non-PEGylated fusion protein are compared under identical reference experimental conditions.
Within certain embodiments of the invention, compositions may be combined in order to achieve a desired effect (e.g., two or more compositions such as a first composition of microspheres comprising an amount (e.g., 15% by weight) of a fusion protein of this invention in a gelatin matrix together with 0.1% of a crosslinking agent such as succinaldehye and a second composition of microspheres comprising an amount (e.g., 25% by weight) of a fusion protein of this invention in a gelatin matrix together with about 2% of a crosslinking agent such as succinaldehye may be combined in order to achieve a modified net release rate of a fusion protein of this invention such as both a rapid release plus a slow or prolonged release.
In one aspect, a rapid release can comprise release of about 50% of the fusion protein in a composition in less than about 8 hours. In another aspect, a slow or prolonged release can comprise release of about 50% of the amount of fusion protein in about 2 weeks.
Within yet other aspects of the present invention, a pharmaceutical composition of this invention can be coated onto the surface of an implantable device such as a sterile surgical mesh, wire, stent, prosthetic device, and the like, to form a coated device, the coating comprising a fusion protein of this invention and optionally a carrier such as a polymeric carrier, which coated device may be implanted in a tissue or organ in a patient such as tissue proximal to the eye or part of the eye, or in a blood vessel which feeds blood to the eye, as part of a surgical treatment, which pharmaceutical composition is delivered in a therapeutically effective amount which can prevent or inhibit or delay or retard growth of neovascularization proximal to the location of the device such as retard neovascularization proximal to the macula.
In another aspect, a therapeutically effective amount of fusion protein can prevent or inhibit or delay or retard growth of blood vessels proximal to the macula which is remote from the site of the implanted device.
The concentration of the fusion protein can be from 0.01% to about 20% by weight of the carrier that forms a coating on the device, and the thickness of the coating can be from about 20 micrometers to about 1 millimeter. The coating can be applied by coating means known in the art of coating devices. For example, a coating comprising a pharmaceutical composition of this invention can be applied to the surface of a device by means of a spray or aerosol applicator in which the pharmaceutical composition as a solution in a liquid or fluid comprising a solvent or as a suspension in a liquid or fluid, which liquid or fluid can evaporate during and after application as a spray or an aerosol, is sprayed or aerosolized onto the surface of a device. Optionally, the coated composition can comprise reactive chemical functional groups such as olefins or anhydride groups or active esters or Michael reaction acceptors such as a carbon-carbon double bond conjugated to a carbonyl group, which double bond can react with an amine of a protein or peptide or gelatin such as a carrier protein, which reactive chemical functional groups can chemically or photochemically form crosslinks in the carrier, which can prevent solubilization or limit or modify or control swelling (as a function of concentration of the number of reactive functional groups or the time of exposure to crosslinking conditions such as ultraviolet or gamma irradiation of the coated device) of the coated carrier by aqueous fluid in the tissue of blood vessel in which the device is implanted. Control of swelling can be useful to control the rate at which a therapeutically effective amount of the fusion protein of this invention migrates from the device into the tissue proximal to the device and further into the body of the patient. A wide variety of crosslinking chemistry known in the art can be useful in this aspect of the invention as long as the biological activity of the fusion protein is not negated or eliminated. If an organic solvent or supercritical fluid or liquefied gas is used in the coating process, then a pharmaceutically acceptable carrier can be selected which does not immediately dissolve in the aqueous medium present in tissue proximal to the site of implantation but permits permeation of a therapeutically effective amount of the fusion protein into the aqueous medium.
Other methods of coating a device can be used such as dip coating of a composition, painting, curtain coating, and lamination of a pharmaceutical composition of this invention. In one embodiment, the surface of a device can be first coated with a first coating layer or primer layer such as gelatin or polyvinyl alcohol, which is then subsequently optionally crosslinked, and then coated with a pharmaceutical composition of this invention as a second coating layer. The primer layer can be selected to adhere to the surface of the metal or polymeric device and to adhere to the carrier of the second coating layer such as gelatin. The primer layer can also comprise immobilized chemical functional groups (e.g., which can be attached to a polymer in the primer layer) and which can form crosslinking bonds with the second layer. The primer layer can optionally contain relatively mobile molecules comprising for example two or more reactive functional groups such as a dialdehyde such as succinaldehye, which molecules can migrate into the second layer and react with chemical functional groups therein to form crosslinking molecular bridges.
In another embodiment, a pharmaceutically acceptable third layer can be overcoated on the second layer on the device, the third layer optionally void of a fusion protein of this invention. The third layer (e.g., a gelatin layer) can serve to control or modify the release rate of the fusion protein from the device, for example by being able to dissolve or swell or increase its permeability with respect to water or the fusion protein as a function of time to expose the second layer comprising the pharmaceutical composition of this invention to aqueous media from the tissue.
Within one embodiment of the invention a surgical mesh device comprising a pharmaceutical composition of the present invention coated on the surface of a wire or polymer mesh may be utilized or implanted in a patient such as during a surgical procedure on the eye of a patient. The coated mesh device can release a therapeutically effective amount of the active component (such as C3APLT or an active mutant or truncated form thereof) of the pharmaceutical composition sufficient to prevent neovascularization in Bruch's membrane proximal to the macula and proximal to the site of implantation of the coated device. The fusion protein can migrate from the device at a rate sufficient to provide a therapeutically effective concentration range in the tissue proximal to the device.
A currently preferred concentration range is about 0.0001 micrograms of fusion protein per cubic centimeter (cc) of tissue to about 100 micrograms per cubic centimeter of tissue can be useful. A currently more preferred therapeutically effective concentration range is about 0.001 micrograms per cc to about 50 micrograms per cc of tissue.
In one embodiment of the invention, the fusion protein can have molecular weight of from about 240,000 daltons to about 300,000 daltons.
Another aspect of the invention comprises a pharmaceutical composition of this invention in a kit of parts such as a kit comprising a container and a pharmaceutical composition of this invention; a kit comprising a sealed vial and a pharmaceutical composition of this invention; a kit comprising a sterile syringe and a pharmaceutical composition of this invention; a kit comprising a sterile syringe containing a pharmaceutical composition of this invention; a kit comprising a spray or aerosol applicator and a pharmaceutical composition of this invention; a kit comprising a brush applicator and a pharmaceutical composition of this invention; a kit comprising a cannula and a pharmaceutical composition of this invention; a kit comprising a powder applicator and a pharmaceutical composition of this invention (which powder applicator can be used to administer a pharmaceutical dosage form of this invention as a powder by sprinkle application of a dried (e.g., lyophilized) powder in a topical application to a tissue; a kit comprising a coated implantable device and a pharmaceutical composition of this invention, wherein administration is by implantation.
In accordance with the present invention, the transport agent region may be at the amino-terminal end of the polypeptide (i.e., protein) and the ADP-ribosyl transferase C3 or ADP-ribosyl transferase C3 analogue may be at the carboxy-terminal end of the polypeptide (i.e., protein).
In accordance with the present invention, the transport agent region may be at the carboxy-terminal end of the polypeptide (i.e., protein) and the ADP-ribosyl transferase C3 or ADP-ribosyl transferase C3 analogue may be at the amino-terminal end of the polypeptide (i.e., protein).
In a further aspect, the present invention provides a method of (for) suppressing the inhibition of neuronal axon growth (e.g., in a mammal, (e.g., human, animal)) comprising administering (e.g., delivering) a member selected from the group consisting of a drug delivery construct, a drug conjugate, a fusion protein and a polypeptide (e.g. including pharmaceutically acceptable chemical equivalents thereof), said polypeptide comprising at least one (one or more) transport agent region and an active agent region selected from the group consisting of ADP-ribosyl transferase C3 and ADP-ribosyl transferase C3 analogues (directly) at (to) a central nervous system (CNS) lesion site or a peripheral nervous system (PNS) lesion site (of a patient), in an amount effective to counteract said inhibition. Such application could be useful for treatment of a wide variety of peripheral neuropathies, such as diabetic neuropathy.
The present invention, for example, provides recombinant Rho antagonists comprising C3 enzymes with basic stretches of amino acids (e.g., a basic amino acid rich region) or a proline rich region added to the C3 coding sequence to facilitate the uptake thereof into tissue or cells for the repair and/or promotion of repair or promotion of growth in the CNS, even in the lack of traumatic axon damage. Examples of basic amino acid rich regions and proline rich regions are given below.
In yet a further aspect, the present invention provides a method of (for) facilitating axon growth (e.g., in a mammal, (e.g., human, animal)) comprising delivering a polypeptide or conjugate comprising at least one transport agent region and an active agent region selected from the group consisting of ADP-ribosyl transferase C3 and ADP-ribosyl transferase C3 analogues directly at a central nervous system (CNS) lesion site or a peripheral nervous system (PNS) lesion site, in an amount effective to facilitate said growth.
In an additional aspect, the present invention provides a method of (for) treating nerve injury (e.g., in a mammal, (e.g., human, animal)) comprising delivering a polypeptide or conjugate comprising at least one transport agent region and an active agent region selected from the group consisting of ADP-ribosyl transferase C3 and ADP-ribosyl transferase C3 analogues directly at (to) a central nervous system (CNS) lesion site or a peripheral nervous system (PNS) lesion site.
In yet an additional aspect, the present invention provides a method of (for) preventing cell apoptosis (e.g., in a mammal, (e.g., human, animal)) comprising delivering a polypeptide or conjugate comprising at least one transport agent region and an active agent region selected from the group consisting of ADP-ribosyl transferase C3 and ADP-ribosyl transferase C3 analogues directly at a central nervous system (CNS) lesion site or a peripheral nervous system (PNS) lesion site.
In another aspect, the present invention provides a method of (for) treating ischemic damage related to stroke (e.g., in a mammal, (e.g., human, animal)) comprising delivering a polypeptide or conjugate comprising at least one transport agent region and an active agent region selected from the group consisting of ADP-ribosyl transferase C3 and ADP-ribosyl transferase C3 analogues directly at a central nervous system (CNS) lesion site (to said mammal).
In yet another aspect, the present invention provides a method of (for) suppressing Rho activity comprising delivering a polypeptide or conjugate comprising at least one transport agent region and an active agent region selected from the group consisting of ADP-ribosyl transferase C3 and ADP-ribosyl transferase C3 analogues directly at a central nervous system (CNS) lesion site or a peripheral nervous system (PNS) lesion site, in an amount effective to suppress said activity.
In accordance with an additional aspect, the present invention provides a method of (for) regenerating injured axon (e.g., in a mammal, (e.g., human, animal)) comprising delivering a polypeptide or conjugate comprising at least one transport agent region and an active agent region selected from the group consisting of ADP-ribosyl transferase C3 and ADP-ribosyl transferase C3 analogues directly at a central nervous system (CNS) lesion site or a peripheral nervous system (PNS) lesion site (e.g., in a mammal), in an amount effective to regenerate said injured axon.
In accordance with a further aspect, the present invention provides a method of (for) helping neurons to make new cell connection (developing axon, dendrite, neurite with other (surrounding) cells (neuronal cells) comprising delivering a polypeptide or conjugate comprising at least one transport agent region and an active agent region selected from the group consisting of ADP-ribosyl transferase C3 and ADP-ribosyl transferase C3 analogues directly at a central nervous system (CNS) lesion site or a peripheral nervous system (PNS) lesion site.
In an additional aspect, the present invention provides a method for (of) preparing a polypeptide comprising at least one (one or more) transport agent region and an active agent region, wherein said transport agent region may be selected from the group consisting of SEQ ID NO.: 21, SEQ ID NO.: 26, SEQ ID NO.: 31, SEQ ID NO.: 44, SEQ ID NO.: 45, SEQ ID NO.: 46, SEQ ID NO.: 47, SEQ ID NO.: 48 and analogues thereof, and wherein said active agent region may be selected from the group consisting of ADP-ribosyl transferase C3 and ADP-ribosyl transferase C3 analogues, said method comprising:
a) cultivating a host cell under conditions which provide for the expression of the polypeptide within the cell; and b) recovering the polypeptide by a purification step.
In accordance with the present invention, the purification of polypeptide may be done by affinity methods, ion exchange chromatography, size exclusion chromatography, hydrophobicity or any other purification technique typically used for protein purification. Preferably, the purification step would be performed under non-denaturating conditions. On the other hand, if a denaturating step is required, the protein may be renatured using techniques known in the art.
In another aspect, the present invention provides a polypeptide consisting of a basic amino acid rich region and an active agent region, wherein, amino acids from said basic rich region comprises amino acids selected from the group consisting of Histidine, Asparagine, Glutamine, Lysine and Arginine and wherein the active agent region is ADP-ribosyl transferase C3.
In yet another aspect, the present invention relates to the use of a polypeptide comprising at least one transport agent region and an active agent region, said active agent region being selected from the group consisting of ADP-ribosyl transferase C3 and ADP-ribosyl transferase C3 analogues for the manufacture of a medicament (or a pharmaceutical composition) for suppressing the inhibition of neuronal axon growth.
In accordance with the present invention, the polypeptide may be selected from the group consisting of C3APL (SEQ ID NO.: 4), C3APL (SEQ ID NO.:37), C3APS (SEQ ID NO.:6), C3-TL (SEQ ID NO.:14), C3-TS (SEQ ID NO.:18), C3Basic1 (SEQ ID NO.:25), C3Basic2 (SEQ ID NO.:30), C3Basic3 (SEQ ID NO.:35), SEQ ID NO.: 20 and SEQ ID NO.: 43.
In a further aspect, the present invention relates to the use of a polypeptide comprising at least one transport agent region and an active agent region, said active agent region being selected from the group consisting of ADP-ribosyl transferase C3 and ADP-ribosyl transferase C3 analogues for the manufacture of a medicament (or pharmaceutical composition) for facilitating axon growth.
In accordance with the present invention, the polypeptide may be selected from the group consisting of C3APL (SEQ ID NO.: 4), C3APLT (SEQ ID NO.:37), C3APS (SEQ ID NO.:6), C3-TL (SEQ ID NO.:14), C3-TS (SEQ ID NO.:18), C3Basic1 (SEQ ID NO.:25), C3Basic2 (SEQ ID NO.:30), C3Basic3 (SEQ ID NO.:35), SEQ ID NO.: 20 and SEQ ID NO.: 43.
In yet a further aspect the present invention relates to the use of a polypeptide comprising at least one (one or more) transport agent region and an active agent region, said active agent region being selected from the group consisting of ADP-ribosyl transferase C3 and ADP-ribosyl transferase C3 analogues for the manufacture of a medicament (or pharmaceutical composition) for treating nerve injury (e.g., in a mammal, (e.g., human, animal)).
In accordance with the present invention, the polypeptide may be selected from the group consisting of C3APL (SEQ ID NO.: 4), C3APLT (SEQ ID NO.:37), C3APS (SEQ ID NO.:6), C3-TL (SEQ ID NO.:14), C3-TS (SEQ ID NO.:18), C3Basic1 (SEQ ID NO.:25), C3Basic2 (SEQ ID NO.:30), C3Basic3 (SEQ ID NO.:35), SEQ ID NO.: 20 and SEQ ID NO.: 43.
In accordance with the present invention, the transport agent region discussed herein may be selected from the group consisting of a basic amino acid rich region (region comprising basic amino acid (e.g., arginine, lysine, histidine, glutamine, and/or asparagine)) and a proline rich region (e.g. region comprising prolines).
In accordance with the present invention, the basic amino acid rich region discussed herein may be selected from the group consisting of SEQ ID NO.: 48, a subdomain of HIV Tat protein (e.g., SEQ ID NO.: 46, SEQ ID NO.: 47, or any other subdomain of Tat, that could act as a transport sequence), a homeodomain of antennapedia (e.g., SEQ ID NO.: 44, SEQ ID NO.: 45, or any other domain of antennapedia, that could act as a transport sequence), a homeoprotein transport sequence, a Histidine tag, and analogues thereof (e.g., SEQ ID NO.: 21, SEQ ID NO.: 26, SEQ ID NO.:31).
In accordance with the present invention, the basic amino acid region discussed herein may be selected from the group consisting of SEQ ID NO.: 21 (Basic 1), SEQ ID NO.: 26 (Basic2), SEQ ID NO.: 31 (Basic3), SEQ ID NO.: 44 (APL), SEQ ID NO.: 45 (APS) SEQ ID NO.: 46 (TL), SEQ ID NO.: 47 (TS), and analogues thereof.
In accordance with the present invention, the proline rich region discussed herein may be selected from the group consisting of SEQ ID NO.: 48 (APLT) and analogues thereof.
In another aspect, the present invention provides an isolated polynucleotide comprising at least the polynucleotide sequence (for example the polynucleotide sequence disclosed herein in addition with (or in some cases without) a suitable (DNA) backbone (e.g., plasmid, viral vector)) selected from the group consisting of SEQ ID NO.: 3, SEQ ID NO.: 5, SEQ ID NO.: 13, SEQ ID NO.: 17, SEQ ID NO.: 19, SEQ ID NO.: 24, SEQ ID NO.: 29, SEQ ID NO.: 34, SEQ ID NO.: 36, and SEQ ID NO.: 42.
In yet another aspect, the present invention provides a cell transformed (transfected, transduced, infected, electroporated, micro-injected, etc.) with an isolated polynucleotide comprising at least the polynucleotide sequence (for example the polynucleotide sequence disclosed herein in addition with (or in some cases without) a suitable backbone (e.g., plasmid, viral vector)) selected from the group consisting of SEQ ID NO.: 3, SEQ ID NO.: 5, SEQ ID NO.: 13, SEQ ID NO.: 17, SEQ ID NO.: 19, SEQ ID NO.: 24, SEQ ID NO.: 29, SEQ ID NO.: 34, SEQ ID NO.: 36, and SEQ ID NO.: 42.
In a further aspect, the present invention provides a delivery agent consisting of a cargo moiety in combination with a transport moiety, wherein the transport moiety is selected from the group consisting of SEQ ID NO: 48 and analogues thereof. SEQ ID NO: 48 and analogues thereof act as a transport moiety which facilitate penetration of the cell membrane. Any cargo moiety (e.g., protein, chemicals) linked (e.g. attached) to SEQ ID NO: 48 or to some analogues thereof are encompassed by the present invention. For example, SEQ ID NO: 48 and analogues thereof may be fused to an anticancer agent, a therapeutic agent, an apoptotic agent, an anti-apoptotic agent, a reporter protein, an antibody, an antibody fragment, a dye, a probe, a marker etc. In one aspect, the polypeptidic cell-membrane transport moiety can comprise a peptide containing from about 5 to about 50 amino acids.
In accordance with the present invention, the cargo moiety may retain biological activity following transport moiety-dependent intracellular delivery. Biological activity may include for example, biological properties (e.g. enzymatic activity) as well as its immunological properties. The cargo moiety may have a direct biological effect on the cell, such as for example killing the cell following its internalization or may have an indirect biological effect, for example, the cargo moiety may be a pro-drug that is inactive by itself but becomes active following modification (e.g., cleavage, phosphorylation, etc.) or when a second molecules is introduced inside the cell. The cargo moiety may also be a biologically inactive (i.e., inert) compound such as a labeling molecule (e.g., chemicals, proteins), an imaging molecule etc.
In accordance with the present invention, the agent may be a fusion protein having an amino-terminal that is the cargo moiety and having a carboxy-terminal that is the transport moiety.
In accordance with the present invention the cargo moiety may be selected from the group consisting of analytical molecules (e.g., molecules used in tissue culture experiments, markers, probes, dyes, reporter proteins) therapeutic molecules (e.g., toxin, drug, pro-drug), prophylactic molecules and diagnostic molecules (i.e., molecules used in in vivo or in vitro detection of a specific condition, metabolite, other molecule). Examples of analytical molecules, therapeutic molecules, prophylactic molecules and diagnostic molecules includes proteins (e.g., enzymes (e.g., nucleases, proteases, kinases, etc.), cytokines, chemokines, antigen, antibodies, antibody fragments, reporter proteins such as horseradish peroxidase, beta-galactosidase, fluorescent proteins (e.g., green fluorescent protein)), nucleic acids, polysaccharides, dyes, isotopes (e.g., radioisotope), markers, probes, and other types of chemicals. Transport polypeptides of the present invention may be advantageously attached to cargo molecules by chemical cross-linking or by genetic fusion.
In accordance with the present invention the cargo moiety may be selected from the group consisting of ADP-ribosyl transferase C3 and ADP-ribosyl transferase C3 analogues thereof.
In an additional aspect, the present invention relates to the polypeptide set forth in SEQ ID NO: 48 and analogues thereof.
In yet an additional aspect, the present invention provides a polypeptide as set forth in SEQ ID NO: 48 and analogues thereof, wherein said polypeptide and analogues may be able to act as a transport agent for the intracellular delivery of a cargo agent selected from the group consisting of analytical molecules, therapeutic molecules, prophylactic molecules, and diagnostic molecules.
In accordance with the present invention, the cargo agent may be selected from the group consisting of ADP-ribosyl transferase C3 and ADP-ribosyl transferase C3 analogues thereof.
The transport of a cargo moiety across the cellular membrane (intracellular delivery) may be facilitated (increased) when linked (e.g., genetically fused, chemically cross-linked, etc.) to SEQ ID NO: 48 and analogues thereof. Therefore it is an object of the present invention to provide a method for the intracellular delivery of a cargo moiety, the method comprising exposing the cell to a delivery agent comprising a cargo moiety and a transport moiety, said transport moiety being selected from the group consisting of SEQ ID NO: 48 and analogues thereof and wherein said transport moiety enables the delivery agent to be delivered inside the cell (i.e., across cellular membranes). An example of a cargo moiety that may be delivered across the cell membrane is ADP-ribosyl transferase C3 and analogues thereof. Other examples of a cargo moiety are mentioned herein. The method also comprise bringing the delivery agent comprising a cargo moiety and a transport moiety (SEQ ID NO: 48 and analogues thereof) in the surrounding of a target cell in a manner (e.g., concentration) sufficient to permit the uptake of the delivery agent by the cell. For example, in the case of in vitro (e.g., cell culture) delivery, the delivery agent (in a pharmaceutically acceptable carrier, diluent, excipient, etc.) may be added directly to the extracellular milieu (e.g., cell culture media) of adherent cells (i.e., cell lines or primary cells) or cells in suspension. Alternatively, cells may be harvested and concentrated before being put in contact with the delivery agent. Intracellular delivery may be monitored by techniques known in the art, such as for example, immunofluorescence, immunohistochemistry or by the intrinsic properties of the cargo moiety (e.g., its enzymatic activity).
In vivo delivery (in a mammal) may be performed for example, by exposing (i.e., contacting) a tissue, a nerve injury site, an open wound, etc. with the delivery agent (in a pharmaceutically acceptable carrier, diluent, excipient, fibrin gel etc.) of the present invention in an amount sufficient to promote the biological effect of the cargo moiety (e.g., recovery, healing of the wounded tissue, etc.). In addition, in vivo delivery may be performed by other methods known in the art such as for example, injection via the intramuscular (IM), subcutaneous (SC), intra-dermal (ID), intra-venous (IV) or intra-peritoneal (IP) routes or administration at the mucosal membranes including the oral and nasal cavity membranes using any suitable means. Alternatively, cells may be isolated from a mammal and treated (exposed) ex-vivo (e.g., in gene therapy techniques) with the delivery agent of the present invention before being re-infused in the same individual or in a compatible individual.
The term “Rho antagonists” as used herein includes, but is not restricted to, (known) C3, including C3 chimeric proteins, and like Rho antagonists.
The term “C3 protein” refers to ADP-ribosyl transferase C3 isolated from Clostridium botulinum or a recombinant ADP-ribosyl transferase.
The term “C3-like protein”, “ADP-ribosyl transferase C3-like protein”, “ADP-ribosyl transferase C3 analogue”, “C3-like transferase” or “C3 chimeric proteins” as used herein refers to any protein (polypeptide) having a biological activity similar (e.g., the same, substantially similar), to ADP-ribosyl transferase C3. Examples of such C3-like protein include, for example, but are not restricted to C3APL, C3APLT, C3APS, C3-TL, C3-TS, C3Basic1, C3Basic2 and C3Basic3 and the protein defined in SEQ ID NO.: 20.
The term “nerve injury site” refers to a site of traumatic nerve injury or nerve injury caused by disease. The nerve injury site may be a single nerve (eg sciatic nerve) or a nerve tract comprised of many nerves (eg. damaged region of the spinal cord). The nerve injury site may be in the central nervous system or peripheral nervous system or in any region needing repair. The nerve injury site may form as a result of damage caused by stroke. The nerve injury site may be in the brain as a result of surgery, brain tumour removal or therapy following a cancerous lesion. The nerve injury site may result from stroke, Parkinson's disease, Alzheimer's disease, amyotrophic lateral sclerosis (ALS), diabetes or any other type of neurodegenerative disease.
The term “cargo” refers to a molecule other than the transport moiety and that is either (1) not inherently capable of entering a cell (e.g., cell compartment) or (2) not inherently capable of entering a cell (e.g., cell compartment) at a useful rate. The term “cargo” as used herein refers either to a molecule per se, i.e., before conjugation, or to the cargo moiety of a transport polypeptide-cargo conjugate. Examples of “cargo” include, but are not limited to, small molecules and macromolecules such as polypeptides, nucleic acids (polynucleotides), polysaccharides and chemicals.
As used herein, the term “delivery agent” relates to an agent comprising a cargo moiety and a transport moiety. Examples of cargo moiety are discussed above and includes for example ADP-ribosyl transferase C3 and ADP-ribosyl transferase C3 analogues. Examples of transport moiety comprise for example SEQ ID NO: 48 and analogues thereof.
“Polynucleotide” generally refers to any polyribonucleotide or polydeoxyribonucleotide, which may be unmodified RNA or DNA, or modified RNA or DNA. “Polynucleotides” include, without limitation single-and double-stranded DNA, DNA that is a mixture of single-and double-stranded regions, single-and double-stranded RNA, and RNA that is a mixture of single-and double-stranded regions, hybrid molecules comprising DNA and RNA that may be single-stranded or, more typically, double-stranded or a mixture of single-and double-stranded regions. In addition, “polynucleotide” refers to triple-stranded regions comprising RNA or DNA or both RNA and DNA. The term polynucleotide also includes DNAs or RNAs containing one or more modified bases and DNAs or RNAs with backbones modified for stability or for other reasons. “Modified” bases include, for example, tritylated bases and unusual bases such as inosine. A variety of modifications has been made to DNA and RNA; thus “polynucleotide” embraces chemically, enzymatically or metabolically modified forms of polynucleotides as typically found in nature, as well as the chemical forms of DNA and RNA characteristic of viruses and cells. “Polynucleotide” includes but is not limited to linear and end-closed molecules. “Polynucleotide” also embraces relatively short polynucleotides, often referred to as oligonucleotides.
“Polypeptides” refers to any peptide or protein comprising two or more amino acids joined to each other by peptide bonds or modified peptide bonds (i.e., peptide isosteres). “Polypeptide” refers to both short chains, commonly referred as peptides, oligopeptides or oligomers, and to longer chains generally referred to as proteins. As described above, polypeptides may contain amino acids other than the 20 gene-encoded amino acids.
As used herein the term “analogues” relates to mutants, variants, chimeras, fusions, deletions, additions and any other type of modifications made relative to a given polypeptide. The term “analogue” is synonym of homologue, derivative and chemical equivalent or biological equivalent.
As used herein, the term “homologous” sequence relates to nucleotide or amino acid sequence derived from the DNA sequence or polypeptide sequence of C3APL, C3APLT, C3APS, C3-TL, C3-TS, C3Basic1, C3Basic2 and C3Basic3.
As used herein, the term “heterologous” sequence relates to DNA sequence or amino acid sequence of a heterologous polypeptide and includes sequence other than that of C3APL, C3APLT, C3APS, C3-TL, C3-TS, C3Basic1, C3Basic2 and C3Basic3.
As used herein the term “basic amino acid rich region” relates to a region of a protein with a high content of the basic amino acids such as Arginine, Histidine, Asparagine, Glutamine, Lysine (Lys). A “basic amino acid rich region” may have, for example 15% or more (up to 100%) of basic amino acids. In some instance, a “basic amino acid rich region” may have less than 15% of basic amino acids and still function as a transport agent region. More preferably, a basic amino acid region will have 30% or more (up to 100%) of basic amino acids.
As used herein the term “proline rich region” refers to a region of a protein with 5% or more (up to 100%) of proline in its sequence. In some instance a “proline rich region” may have between 5% and 15% of prolines. Additionally, a “proline rich region” refers to a region, of a protein containing more prolines than what is generally observed in naturally occurring proteins (e.g., proteins encoded by the human genome). “Proline rich region” of the present invention function as a transport agent region.
The term “proline-rich region” can further refer to any linear sequence of 10 amino acids linked together by peptide amide bonds within a molecule comprising a peptide or protein, wherein at least 3 out of the 10 amino acids in the linear sequence are proline residues, wherein each proline is covalently linked in a peptide amide bond at its nitrogen and in another peptide amide bond at its carboxylic (carbonyl) site. A proline-rich region in any 10 amino acid sequence within a peptide can comprise 2 or more proline residues and 8 or fewer non-proline amino acids. For example, in one aspect, a proline-rich region in a peptide comprising a 10 amino acid sequence within a peptide comprising 10 or more amino acids can comprise 2 proline residues and 8 non-proline amino acid residues distributed in any combination among the 10 amino acids. In another aspect, a proline-rich region in a peptide comprising a 10 amino acid sequence within a peptide comprising 10 or more amino acids can comprise 3 proline residues and 7 non-proline amino acid residues distributed in any combination among the 10 amino acids. In another aspect, a proline-rich region in a peptide comprising a 10 amino acid sequence within a peptide comprising 10 or more amino acids can comprise 4 proline residues and 6 non-proline amino acid residues distributed in any combination among the 10 amino acids. In another aspect, a proline-rich region in a peptide comprising a 10 amino acid sequence within a peptide comprising 10 or more amino acids can comprise 5 proline residues and 5 non-proline amino acid residues distributed in any combination among the 10 amino acids. In another aspect, a proline-rich region in a peptide comprising a 10 amino acid sequence within a peptide comprising 10 or more amino acids can comprise 6 proline residues and 4 non-proline amino acid residues distributed in any combination among the 10 amino acids. In another aspect, a proline-rich region in a peptide comprising a 10 amino acid sequence within a peptide comprising 10 or more amino acids can comprise 7 proline residues and 3 non-proline amino acid residues distributed in any combination among the 10 amino acids. In another aspect, a proline-rich region in a peptide comprising a 10 amino acid sequence within a peptide comprising 10 or more amino acids can comprise 8 proline residues and 2 non-proline amino acid residues distributed in any combination among the 10 amino acids. In another aspect, a proline-rich region in a peptide comprising a 10 amino acid sequence within a peptide comprising 10 or more amino acids can comprise 9 proline residues and 1 non-proline amino acid residue distributed in any combination among the 10 amino acids. In another aspect, a proline-rich region in a peptide comprising a 10 amino acid sequence within a peptide comprising 10 or more amino acids can comprise 10 proline residues.
In another aspect, a “proline-rich region” refers to an amino acid sequence region of a protein containing more prolines than that which is generally observed in naturally occurring proteins (e.g., proteins encoded by the human genome).
A “proline-rich region” of a peptide in a composition of the present invention can function to enhance the rate of transport of a fusion protein of this invention through a cell membrane.
A non-proline-rich region of a peptide or protein can comprise a sequence of 10 amino acids covalently linked by peptide bonds, which region contains zero or one proline residues.
A cell membrane transport-enhancing peptide of a composition of this invention can comprise one or more than one proline-rich regions, each of which can be the same or different sequence of amino acids, and each of which is covalently linked together by a peptide bond or by the peptide bonds comprising one or more non-proline-rich amino-acid sequence which may each be the same or different when the non-proline-rich amino-acid sequence comprises more than 10 amino acids.
In one aspect of this invention, a preferred composition comprises a cell-permeable fusion protein conjugate comprising a proline-rich polypeptidic cell-membrane transport moiety comprising a proline-rich amino acid sequence added to the C-terminal region of a Clostridium botulinum C3 exotransferase unit, or a functional analog thereof, in a fusion protein conjugate. An especially preferred composition is a fusion protein designated C3APLT. In another aspect of this invention, a preferred composition comprises a cell-permeable fusion protein conjugate comprising a proline-rich polypeptidic cell-membrane transport moiety comprising a proline-rich amino acid sequence added to the N-terminal region of a Clostridium botulinum C3 exotransferase unit, or a functional analog thereof, in a fusion protein conjugate. Fusion protein compositions comprising a proline-rich amino acid sequence added to the N-terminal region of a Clostridium botulinum C3 exotransferase unit, or a functional analog thereof, are sometimes referred to herein as analogs or variants of C3APLT.
Fusion protein functional analogs of a Clostridium botulinum C3 exotransferase unit can comprise polypeptides such as biologically active fragments and altered-amino-acid-sequence analogs of a fusion protein such as C3APLT, wherein the biological activity of such fragments and altered-amino-acid-sequence analogs of C3APLT derives from a mechanism of action essentially similar to that of C3APLT. Such fragments can comprise or encompass amino acid sequences having truncations of one or more amino acids relative to that in C3APLT. Such fragments comprise or encompass amino acid sequences having truncations (or eliminations) of one or more amino acids relative to the sequence of amino acids in C3APLT, wherein a truncation may originate from the amino or N-terminus, from the carboxy or C-terminus, or from the interior of the protein sequence. Analogs and variants of a fusion protein such as C3APLT of the invention can comprise an insertion or a substitution of one or more amino acids.
Compositions of this invention comprising fragments, analogs and variants useful in this invention have the biological property of C3APLT and C3 that is capable of inactivation a Rho GTPase by ADP-ribosylation. Preferably a fusion protein of this invention is capable of inactivation of more than one Rho GTPase. Preferably the activity of a fusion protein of this invention with respect to ADP-ribosylation of a Rho GTPase is in the range of 0.5 to 10 times the activity of Clostridium botulinum C3 in inactivation of a Rho GTPase, more preferably 0.5 to 100 times the activity of Clostridium botulinum C3 in inactivation of a Rho GTPase, and most preferably 0.8 to 1000 times the activity of Clostridium botulinum C3 in inactivation of a Rho GTPase.
With respect to inactivation of a Rho GTPase by ADP-ribosylation, the activity provided by the presence of the Glu 173 residue in Clostridium botulinum C3 exoenzyme is present in fusion proteins of this invention. Preferably, the amino acid sequence of a fusion protein of this invention comprises the Glu 173 amino acid residue in Clostridium botulinum C3 exoenzyme and the fusion protein of this invention exhibits ADP-ribosylation activity in the range of 0.5 to 10 times the ADP-ribosylation activity of Clostridium botulinum C3, more preferably 0.5 to 100 times the ADP-ribosylation activity of Clostridium botulinum C3, and most preferably 0.8 to 1000 times the ADP-ribosylation activity of Clostridium botulinum C3. The particular portion of the structure of Clostridium botulinum C3 that must be conserved to retain ADP-ribosylation activity can be found in Saito et al., FEBS Letters, 371:105-109, 1995, the entire contents of which is hereby incorporated by reference.
As used herein the term “to help neuron make new connections with other cells” or “helping neurons to make new cell connection” means that upon treatment of cells (e.g., neuron(s)) or tissue with a drug delivery construct, a conjugate, a fusion-protein, a polypeptide or a pharmaceutical compositions of the present invention, neurons may grow (develop) for example new dendrite, new axon or new neurite (i.e., cell bud), or already existing dendrite(s), axon or neurite (i.e., cell bud) are induce to grow to a greater extent.
As used herein, the term “vector” refers to an autonomously replicating DNA or RNA molecule into which foreign DNA or RNA fragments are inserted and then propagated in a host cell for either expression or amplification of the foreign DNA or RNA molecule. The term “vector” comprises and is not limited to a plasmid (e.g., linearized or not) that can be used to transfer DNA sequences from one organism to another.
The term “pharmaceutically acceptable carrier” or “adjuvant” and “physiologically acceptable vehicle” and the like are to be understood as referring to an acceptable carrier or adjuvant that may be administered to a patient, together with a compound of this invention, and which does not destroy the pharmacological activity thereof. Further, as used herein “pharmaceutically acceptable carrier” or “pharmaceutical carrier” are known in the art and include, but are not limited to, 0.01-0.1 M and preferably 0.05 M phosphate buffer or 0.8% saline. Additionally, such pharmaceutically acceptable carriers may be aqueous or non-aqueous solutions, suspensions, and emulsions. Examples of non-aqueous solvents are propylene glycol, polyethylene glycol, vegetable oils such as olive oil, and injectable organic esters such as ethyl oleate. Aqueous carriers include water, alcoholic/aqueous solutions, emulsions or suspensions, including saline and buffered media. Parenteral vehicles include sodium chloride solution, Ringer's dextrose, dextrose and sodium chloride, lactated Ringer's or fixed oils. Intravenous vehicles include fluid and nutrient replenishers, electrolyte replenishers such as those based on Ringer's dextrose, and the like. Preservatives and other additives may also be present, such as, for example, antimicrobials, antioxidants, collating agents, inert gases and the like.
As used herein, “pharmaceutical composition” means therapeutically effective amounts (dose) of the agent together with pharmaceutically acceptable diluents, preservatives, solubilizers, emulsifiers, adjuvant and/or carriers. A “therapeutically effective amount” as used herein refers to that amount which provides a therapeutic effect for a given condition and administration regimen. Such compositions are liquids or lyophilized or otherwise dried formulations and include diluents of various buffer content (e.g., Tris-HCl, acetate, phosphate), pH and ionic strength, additives such as albumin or gelatin to prevent absorption to surfaces, detergents (e.g., Tween 20, Tween 80, Pluronic F68, bile acid salts). Solubilizing agents (e.g., glycerol, polyethylene glycerol), anti-oxidants (e.g., ascorbic acid, sodium metabisulfite), preservatives (e.g., thimerosal, benzyl alcohol, parabens), bulking substances or tonicity modifiers (e.g., lactose, mannitol), covalent attachment of polymers such as polyethylene glycol to the protein, complexation with metal ions, or incorporation of the material into or onto particulate preparations of polymeric compounds such as polylactic acid, polyglycolic acid, hydrogels, etc, or onto liposomes, microemulsions, micelles, unilamellar or multilamellar vesicles, erythrocyte ghosts, or spheroplasts. Such compositions will influence the physical state, solubility, stability, rate of in vivo release, and rate of in vivo clearance. Controlled or sustained release compositions include formulation in lipophilic depots (e.g., fatty acids, waxes, oils). Also comprehended by the invention are particulate compositions coated with polymers (e.g., poloxamers or poloxamines). Other embodiments of the compositions of the invention incorporate particulate forms protective coatings, protease inhibitors or permeation enhancers for various routes of administration, including parenteral, pulmonary, nasal and oral routes. In one embodiment the pharmaceutical composition is administered parenterally, paracancerally, transmucosally, transdermally, intramuscularly, intravenously, intradermally, subcutaneously, intraperitonealy, intraventricularly, intracranially intratumorally or more preferably, directly at a central nervous system (CNS) lesion site or a peripheral nervous system (PNS) lesion site.
In addition, the term “pharmaceutically effective amount” or “therapeutically effective amount” refers to an amount (dose) effective in treating a patient, having, for example, a nerve injury. It is also to be understood herein that a “pharmaceutically effective amount” may be interpreted as an amount giving a desired therapeutic effect, either taken into one dose or in any dosage or route or taken alone or in combination with other therapeutic agents. In the case of the present invention, a “pharmaceutically effective amount” may be understood as an amount of ADP-ribosyl transferase C3 or ADP-ribosyl transferase C3 analogues (e.g., fusion proteins) of the present invention which may for example, suppress (e.g., totally or partially) the inhibition of neuronal axon growth, facilitate axon growth, prevent cell apoptosis, suppress Rho activity, help regenerate injured axon, or which may help neurons to make new connections with other cells.
As may be appreciated, a number of modifications may be made to the polypeptides of the present invention, such as for example the active agent region (e.g., ADP-ribosyl transferase C3 or ADP-ribosyl transferase C3 analogue) or the transport agent region (e.g., a subdomain of HIV Tat protein, or a homeodomain of antennapedia) and fragments thereof without deleteriously affecting the biological activity of the polypeptides or fragments. Polypeptides of the present invention comprises for example, those containing amino acid sequences modified either by natural processes, such as posttranslational processing, or by chemical modification techniques which are known in the art. Modifications may occur anywhere in a polypeptide including the polypeptide backbone, the amino acid side-chains and the amino or carboxy termini. It will be appreciated that the same type of modification may be present in the same or varying degrees at several sites in a given polypeptide. Also, a given polypeptide may contain many types of modifications. Polypeptides may be branched as a result of ubiquitination, and they may be cyclic, with or without branching. Cyclic, branched and branched cyclic polypeptides may result from posttranslational natural processes or may be made by synthetic methods. Modifications comprise for example, without limitation, acetylation, acylation, addition of acetomidomethyl (Acm) group, ADP-ribosylation, amidation, covalent attachment to fiavin, covalent attachment to a heme moiety, covalent attachment of a nucleotide or nucleotide derivative, covalent attachment of a lipid or lipid derivative, covalent attachment of phosphatidylinositol, cross-linking, cyclization, disulfide bond formation, demethylation, formation of covalent cross-links, formation of cystine, formation of pyroglutamate, formylation, gamma-carboxylation, glycosylation, GPI anchor formation, hydroxylation, iodination, methylation, myristoylation, oxidation, proteolytic processing, phosphorylation, prenylation, racemization, selenoylation, sulfation, transfer-RNA mediated addition of amino acids to proteins such as arginylation and ubiquitination (for reference see, Protein-structure and molecular properties, 2 nd Ed., T. E. Creighton, W.H. Freeman and Company, New-York, 1993).
Other type of polypeptide modification may comprises for example, amino acid insertion (i.e., addition), deletion and substitution (i.e., replacement), either conservative or non-conservative (e.g., D-amino acids, desamino acids) in the polypeptide sequence where such changes do not substantially alter the overall biological activity of the polypeptide. Polypeptides of the present invention comprise for example, biologically active mutants, variants, fragments, chimeras, and analogues; fragments encompass amino acid sequences having truncations of one or more amino acids, wherein the truncation may originate from the amino terminus (N-terminus), carboxy terminus (C-terminus), or from the interior of the protein. Analogues of the invention involve an insertion or a substitution of one or more amino acids. Variants, mutants, fragments, chimeras and analogues may have the biological properties of polypeptides of the present invention which comprise for example (without being restricted to the present examples) to facilitate neuronal axon growth, to suppress the inhibition of neuronal axon growth, to facilitate neurite growth, to inhibit apoptosis, to treat nerve injury, to regenerate injured axon and/or to act as a Rho antagonist.
As it may be exemplified (Example 13: reverse Tat sequence), in some instance, the order of the amino acids in a particular polypeptide is not critical. As for the transport agent region described herein, the transport function of this region may be preserved even if the amino acids are not in their original (as it is found in nature) order (sequence).
Example of substitutions may be those, which are conservative (i.e., wherein a residue is replaced by another of the same general type). As is understood, naturally occurring amino acids may be sub-classified as acidic, basic, neutral and polar, or neutral and non-polar. Furthermore, three of the encoded amino acids are aromatic. It may be of use that encoded polypeptides differing from the determined polypeptide of the present invention contain substituted codons for amino acids, which are from the same group as that of the amino acid being replaced. Thus, in some cases, the basic amino acids Lys, Arg and His may be interchangeable; the acidic amino acids Asp and Glu may be interchangeable; the neutral polar amino acids Ser, Thr, Cys, Gln, and Asn may be interchangeable; the non-polar aliphatic amino acids Gly, Ala, Val, Ile, and Leu are interchangeable but because of size Gly and Ala are more closely related and Val, Ile and Leu are more closely related to each other, and the aromatic amino acids Phe, Trp and Tyr may be interchangeable.
It should be further noted that if the polypeptides are made synthetically, substitutions by amino acids, which are not naturally encoded by DNA may also be made. For example, alternative residues include the omega amino acids of the formula NH 2 (CH 2 ) n COOH wherein n is 2-6. These are neutral nonpolar amino acids, as are sarcosine, t-butyl alanine, t-butyl glycine, N-methyl isoleucine, and norleucine. Phenylglycine may substitute for Trp, Tyr or Phe; citrulline and methionine sulfoxide are neutral nonpolar, cysteic acid is acidic, and ornithine is basic. Proline may be substituted with hydroxyproline and retain the conformation conferring properties.
It is known in the art that mutants or variants may be generated by substitutional mutagenesis and retain the biological activity of the polypeptides of the present invention. These variants have at least one amino acid residue in the protein molecule removed and a different residue inserted in its place (one or more nucleotide in the DNA sequence is changed for a different one using known molecular biology techniques, giving a different amino acid upon translation of the corresponding messenger RNA to a polypeptide). For example, one site of interest for substitutional mutagenesis may include but are not restricted to sites identified as the active site(s), or immunological site(s). Other sites of interest may be those, for example, in which particular residues obtained from various species are identical. These positions may be important for biological activity. Examples of substitutions identified as “conservative substitutions” are shown in Table 1. If such substitutions result in a change not desired, then other type of substitutions, denominated “exemplary substitutions” in Table 1, or as further described herein in reference to amino acid classes, are introduced and the products screened.
In some cases it may be of interest to modify the biological activity of a polypeptide by amino acid substitution, insertion, or deletion. For example, modification of a polypeptide may result in an increase in the polypeptide's biological activity, may modulate its toxicity, may result in changes in bioavailability or in stability, or may modulate its immunological activity or immunological identity. Substantial modifications in function or immunological identity are accomplished by selecting substitutions that differ significantly in their effect on maintaining (a) the structure of the polypeptide backbone in the area of the substitution, for example, as a sheet or helical conformation. (b) the charge or hydrophobicity of the molecule at the target site, or (c) the bulk of the side chain. Naturally occurring residues are divided into groups based on common side chain properties:
i. hydrophobic: norleucine, methionine (Met), Alanine (Ala), Valine (Val), Leucine (Leu), Isoleucine (Ile) ii. neutral hydrophilic: Cysteine (Cys), Serine (Ser), Threonine (Thr) iii. acidic: Aspartic acid (Asp), Glutamic acid (Glu) iv. basic: Asparagine (Asn), Glutamine (Gln), Histidine (His), Lysine (Lys), Arginine (Arg) v. residues that influence chain orientation: Glycine (Gly), Proline (Pro); and vi. aromatic: Tryptophan (Trp), Tyrosine (Tyr), Phenylalanine (Phe)
Non-conservative substitutions will entail exchanging a member of one of these classes for another.
TABLE 1
Preferred amino acid substitution
Original
Exemplary
Conservative
residue
substitution
substitution
Ala (A)
Val, Leu, Ile
Val
Arg (R)
Lys, Gln, Asn
Lys
Asn (N)
Gln, His, Lys, Arg
Gln
Asp (D)
Glu
Glu
Cys (C)
Ser
Ser
Gln (Q)
Asn
Asn
Glu (E)
Asp
Asp
Gly (G)
Pro
Pro
His (H)
Asn, Gln, Lys, Arg
Arg
Ile (I)
Leu, Val, Met, Ala,
Leu
Phe, norleucine
Leu (L)
Norleucine, Ile, Val,
Ile
Met, Ala, Phe
Lys (K)
Arg, Gln, Asn
Arg
Met (M)
Leu, Phe, Ile
Leu
Phe (F)
Leu, Val, Ile, Ala
Leu
Pro (P)
Gly
Gly
Ser (S)
Thr
Thr
Thr (T)
Ser
Ser
Trp (W)
Tyr
Tyr
Tyr (Y) T
rp, Phe, Thr, Ser
Phe
Val (V)
Ile, Leu, Met, Phe,
Leu
Ala, norleucine
Amino acids sequence insertions (e.g., additions) include amino and/or carboxyl-terminal fusions ranging in length from one residue to polypeptides containing a hundred or more residues, as well as intrasequence insertions of single or multiple amino acid residues. Other insertional variants include the fusion of the N-or C-terminus of the protein to a homologous or heterologous polypeptide forming a chimera. Chimeric polypeptides (i.e., chimeras, polypeptide analogue) comprise sequence of the polypeptides of the present invention fused to homologous or heterologous sequence. Said homologous or heterologous sequence encompass those which, when formed into a chimera with the polypeptides of the present invention retain one or more biological or immunological properties.
Other type of chimera generated by homologous fusion includes new polypeptides formed by the repetition of two or more polypeptides of the present invention. The number of repeat may be, for example, between 2 and 50 units (i.e., repeats). In some instance, it may be useful to have a new polypeptide with a number of repeat greater than 50. For example, it may be useful to fuse (using cross-linking techniques or recombinant DNA technology techniques) polypeptides such as C3APL, C3APLT, C3APS, C3-TL, C3-TS, C3Basic1, C3Basic2 and C3Basic3 either to themselves (e.g., C3APLT fused to C3APLT) or to another polypeptide of the present invention (e.g., C3APLT fused to C3APL).
In addition, a transport agent such as for example, a subdomain of HIV Tat protein, and a homeodomain of antennapedia may be repeated more than one time in a polypeptide comprising the ADP-ribosyl transferase C3 or ADP-ribosyl transferase C3 analogues. The transport agent region may be either at the amino-terminal region of an ADP-ribosyl transferase C3 or ADP-ribosyl transferase C3 analogues or at its carboxy-terminal region or at both regions. The repetition of a transport agent region may affect (e.g., increase) the uptake of the ADP-ribosyl transferase C3 or ADP-ribosyl transferase C3 analogues by a desired cell.
Heterologous fusion includes new polypeptides made by the fusion of polypeptides of the present invention with heterologous polypeptides. Such polypeptides may include but are not limited to bacterial polypeptides (e.g., betalactamase, glutathione-S-transferase, or an enzyme encoded by the E. coli trp locus), yeast protein, viral proteins, phage proteins, bovine serum albumin, chemotactic polypeptides, immunoglobulin constant region (or other immunoglobulin regions), albumin, or ferritin.
Other type of polypeptide modification includes amino acids sequence deletions (e.g., truncations). Those generally range from about 1 to 30 residues, more preferably about 1 to 10 residues and typically about 1 to 5 residues.
Mutants, Variants and Analogues Proteins
Mutant polypeptides will possess one or more mutations, which are deletions (e.g., truncations), insertions (e.g., additions), or substitutions of amino acid residues. Mutants can be either naturally occurring (that is to say, purified or isolated from a natural source) or synthetic (for example, by performing site-directed mutagenesis on the encoding DNA or made by other synthetic methods such as chemical synthesis). It is thus apparent that the polypeptides of the invention can be either naturally occurring or recombinant (that is to say prepared from the recombinant DNA techniques).
A protein at least 50% identical, as determined by methods known to those skilled in the art (for example, the methods described by Smith, T. F. and Waterman M. S. (1981) Ad. Appl. Math., 2:482-489, or Needleman, S. B. and Wunsch, C. D. (1970) J. Mol. Biol., 48: 443-453), to those polypeptides of the present invention, for example C3APL, C3APLT, C3APS, C3-TL, C3-TS, C3Basic1, C3Basic2 and C3Basic3 are included in the invention, as are proteins at least 70% or 80% and more preferably at least 90% identical to the protein of the present invention. This will generally be over a region of at least 5, preferably at least 20 contiguous amino acids.
“Variant” as the term used herein, is a polynucleotide or polypeptide that differs from reference polynucleotide or polypeptide respectively, but retains essential properties. A typical variant of a polynucleotide differs in nucleotide sequence from another, reference polynucleotide. Changes in the nucleotide sequence of the variant may or may not alter the amino acid sequence of a polypeptide encoded by the reference polynucleotide. Nucleotide changes may result in amino acid substitutions, additions, deletions, fusion and truncations in the polypeptide encoded by the reference sequence, as discussed herein. A typical variant of a polypeptide differs in amino acid sequence from another, reference polypeptide. Generally, differences are limited so that the sequence of the reference polypeptide and the variant are closely similar overall and, in many regions, identical. A variant and reference polypeptide may differ in amino acid by one or more substitutions, additions, deletions, or any combination therefore. A substituted or inserted amino acid residue may or may not be one encoded by the genetic code. A variant polynucleotide or polypeptide may be a naturally occurring such as an allelic variant, or it may be a variant that is not known to occur naturally. Non-naturally occurring variants of polynucleotides and polypeptides may be made by mutagenesis techniques or by direct synthesis.
Amino acid sequence variants may be prepared by introducing appropriate nucleotide changes into DNA, or by in vitro synthesis of the desired polypeptide. Such variant include, for example, deletions, insertions, or substitutions of residues within the amino acid sequence. A combination of deletion, insertion and substitution can be made to arrive at the final construct, provided that the final protein product possesses the desired biological activity, or characteristics. The amino acid changes also may alter posttranslational processes such as changing the number or position of the glycosylation sites, altering the membrane anchoring characteristics, altering the intra-cellular location by inserting, deleting or otherwise affecting the transmembrane sequence of the native protein, or modifying its susceptibility to proteolytic cleavage.
Unless otherwise indicated, the recombinant DNA techniques utilized in the present invention are standard procedures, known to those skilled in the art. Example of such techniques are explained in the literature in sources such as J. Perbal, A Practical Guide to Molecular Cloning, John Wiley and Sons (1984), J. Sambrook et al., Molecular Cloning: A Laboratory Manual, Cold Spring Harbor Laboratory Press (1989), T. A. Brown (editor), Essential Molecular Biology: A Practical Approach, Volumes 1 and 2, IRL Press (1991), D. M. Glover and B. D. Hames (editors), DNA Cloning: A Practical Approach, Volumes 1-4, IRL Press (1995 and 1996), and F. M. Ausubel et al. (editors), Current Protocols in Molecular Biology, Greene Pub. Associates and Wiley-Interscience (1988, including all updates until present) and are incorporated herein by reference.
It is to be understood herein, that if a “range” or “group of substances” is mentioned with respect to a particular characteristic (e.g. amino acid groups, temperature, pressure, time and the like) of the present invention, the present invention relates to and explicitly incorporates herein each and every specific member and combination of sub-ranges or sub-groups therein whatsoever. Thus, any specified range or group is to be understood as a shorthand way of referring to each and every member of a range or group individually as well as each and every possible sub-ranges or sub-groups encompassed therein; and similarly with respect to any sub-ranges or sub-groups therein. Thus, for example,
a) with respect to a sequence comprising up to 50 base units it is to be understood as specifically incorporating herein each and every individual unit, as well as sub-range of units; b) with respect to reaction time, a time of 1 minute or more is to be understood as specifically incorporating herein each and every individual time, as well as sub-range, above 1 minute, such as for example 1 minute, 3 to 15 minutes, 1 minute to 20 hours, 1 to 3 hours, 16 hours, 3 hours to 20 hours etc.; c) with respect to polypeptides, a polypeptide analogue comprising a particular sequence and having an addition of at least one amino acid to its amino-terminus or to its carboxy terminus is to be understood as specifically incorporating each and every individual possibility, such as for example one, two, three, ten, eighteen, forty, etc.; d) with respect to polypeptides, a polypeptide analogue having at least 90% of its amino acid sequence identical to a particular amino acid sequence is to be understood as specifically incorporating each and every individual possibility (excluding 100%), such as for example, a polypeptide analogue having 90%, 90.5%, 91%, 93.7%, 97%, 99%, etc., of its amino acid sequence identical to a particular amino acid sequence; e) with respect to polypeptides, a polypeptide analogue having at least 70% of its amino acid sequence identical to a particular amino acid sequence is to be understood as specifically incorporating each and every individual possibility (excluding 100%), such as for example, a polypeptide analogue having 70%, 72.3%, 73%, 88.6%, 98% etc., of its amino acid sequence identical to a particular amino acid sequence; f) with respect to polypeptides, a polypeptide analogue having at least 50% of its amino acid sequence identical to a particular amino acid sequence is to be understood as specifically incorporating each and every individual possibility (excluding 100%), such as for example, a polypeptide analogue having 50%, 54%, 66.7%, 70.2%, 84%, 93% etc., of its amino acid sequence identical to that particular amino acid sequence; g) with respect to polypeptide, a polypeptide comprising at least one transport agent region is to be understood as specifically incorporating each and every individual possibility, such as for example a polypeptide having one, two, five, ten, etc., transport agent region; and h) similarly with respect to other parameters such as low pressures, concentrations, elements, etc.
It is also to be understood herein that “g” or “gm” is a reference to the gram weight unit; and that “C”, or “° C.” is a reference to the Celsius temperature unit.
TABLE 2
Abbreviations
Abbreviation
Full name
C3
ADP-ribosyl transferase C3
NGF
Nerve growth factor
BDNF
Brain-derived neurotrophic factor
C. or ° C.
Degree Celcius
ml
milliliter
μl or ul
microliter
μM or uM
micromolar
mM
millimolar
M
molar
N
normal
CNS
Central nervous system
PNS
Peripheral nervous system
HIV
Human immunodeficiency virus
HIV-1
Human immunodeficiency virus type-1
kDa
kilodalton
GST
Glutathione S-transferase
MTS
Membrane transport sequence
SDS-PAGE
Sodium dodecyl sulfte polyacrylamide gel electrophoresis
PBS
Phosphate buffered saline
U
unit
BBB
Basso, Beattie Breshnahan behavior recovery scale
IPTG
Isopropyl.beta.-D-thiogalactopyranoside
rpm
Rotation per minutes
DTT
dithiothreitol
PMSF
Phenylmethylsulfonyl fluoride
NaCl
Sodium chloride
MgCl 2
Magnesium chloride
HBSS
Hank's balanced salt solution
NaOH
Sodium hydroxide
CSPG
chondroitin sulfate proteoglycan
PKN
Protein kinase N
RSV
Rous sarcoma virus
MMTV
Mouse mammary tumor virus
LTR
Long terminal repeat
HL
Hind limb
FL
Fore limb
neo
neomycin
hygro
hygromycin
IN-1
monoclonal antibody called IN-1
ADP
Adenosine di-phosphate
ATP
Adenosine tri-phosphate
32 P
Isotope 32 of phosphorus
DHFR
Dihydrofolate reductase
PCR
Polymerase chain reaction
The invention in particular provides C3-like proteins, which may have additional amino acids added to the carboxy terminal end of the C3 proteins. Examples of such proteins includes:
C3APL: (C3 antennapedia-long) created by annealing sequences from the antennapedia transcription factor to the 3′ end of the sequence encoding C3 cDNA. The long antennapedia sequence of 60 amino acids containing the homeodomain of antennapedia, was used;
C3APLT: (C3 antennapedia-truncated) created by annealing sequences from the antennapedia transcription factor to the 3′ end of the sequence encoding C3 cDNA. This clone with a frameshift mutation gives a proline-rich transport peptide with good transport activity. This sequence is truncated i.e. shorter than C3APL.
C3APS: A short 11 amino acid sequence of antennapedia that has transmembrane transport properties was fused to the carboxy terminal of C3 to create C3APS;
C3-TL: C3 Tat-long created by fusing amino acids 27 to 72 of Tat to the carboxy terminal of C3 protein;
C3-TS: C3 Tat-short created by fusing the amino acids YGRKRRQRRR (SEQ ID NO:49) to the C3 protein;
C3Basic1 a random basic charge sequence added to the C-terminal of C3;
C3Basic2: a random basic charge sequence added to the C-terminal of C3;
C3Basic3: C3 Tat-short created by fusing the reverse sequence of Tat amino acids RRQRRKKR (SEQ ID NO:50) to the C3 protein.
C3-07: The sequence of C3APLT modified to remove the GST sequence used for purification, and with silent amino acid changes induced when cloned into the pEt expression vector, but which silent amino acid changes maintaining ADP-ribosylation activity of the protein.
C3-07Q189A: The sequence of C3-07 with an amino acid substitution of Glu 189 to Gln 189 in the catalytic domain that removes ADP-ribosylation activity to create an inactive construct.
It has been found that conjugates or fusion proteins (C3-like proteins) Rho antagonists of the present invention are effective to stimulate repair in the CNS after spinal cord injury. The increased cell permeability of new Rho antagonist (new chimeric C3) would now allow treatment of victims of stroke and neurodegenerative disease because Rho signaling pathway is important in repair after stroke (Hitomi, et al. (2000) 67: 1929-39. Trapp et al 2001. Mol. Cell. Neurosci. 17: 883-84). Treatment with Rho antagonists in the adhesive delivery system could be used to enhance the rate of axon growth in the PNS. Also, evidence in the literature now links Rho signaling with formation of Alzheimer's disease tangles through its ability to activate PKN which then phosphorylates tau and neurofilaments (Morissette, et al. (2000) 278: H1769-74., Kawamata, et al. (1998) 18: 7402-10., Amano, et al. (1996) 271: 648-50., Watanabe, et al. (1996) 271: 645-8.). Therefore, Rho antagonists are expected to be useful in the treatment of Alzheimer's disease. The new chimeric C3 drugs should be able to diffuse readily and therefore can promote repair for diseases that are neurodegenerative. Examples include, but are not limited to stroke, traumatic brain injury, Parkinson's disease, Alzheimer's disease and ALS. Moreover, it is now well established that Rho signaling antagonists are effective in the treatment of other diseases. These include, but are not limited to eye diseases such as glaucoma (Honjo, et al. (2001) 42: 137-44., Rao, et al. (2001) 42: 1029-1037) eye diseases such as macular degeneration, retinitis pigmentosa, Stargardt's Disease, diabetic retinopathy, hypertensive retinopathy, and occlusive retinopathy, cancer cell migration and metastasis (Sahai, et al. (1999) 9: 136-45., Takamura, et al. (2001) 33: 577-81., Imamura, et al. (2000) 91: 811-6). The effects of the Rho signaling pathway on smooth muscle relaxation are well established. This has led to the identification of Rho signaling antagonists as effective in treatment of hypertension (Chitaley, et al. (2001) 3: 139-144., Somlyo (1997) 389: 908-911, Uehata, et al. (1997) 389: 990-994), asthma (Nakahara, et al. (2000) 389: 103-6., Ishizaki, et al. (2000) 57: 976-83), and vascular disease (Miyata, et al. (2000) 20: 2351-8., Robertson, et al. (2000) 131: 5-9.) as well as penile erectile dysfunction (Chitaley, et al. (2001) 7: 119-22.). Rho is also important as a cardioprotective protein (Lee et al. 2001. FASEB J. 15:1886-1894).
Rho GTPases include members of the Rho, Rac and Cdc42 family of proteins. Our invention concerns Rho family members of the Rho class. Rho proteins consist of different variants encoded by different genes. For example, PC-12 cells express RhoA, RhoB and RhoC (Lehmann et al 1999 supra); PC-12 cells: Pheochromocytom cell line (Greene A and Tischler, A S PNAS 73:2424 (1976). To inactivate Rho proteins inside cells, Rho antagonists of the C3 family type are effective because they inactivate all forms of Rho (e.g. RhoA, Rho B etc). In contrast, gene therapy techniques, such as introduction of a dominant negative RhoA family member into a diseased cell, will only inactivate that specific RhoA family member.
Recombinant C3 proteins, or C3 proteins that retain the ribosylation activity are also effective in our delivery system and are covered by this invention. In addition, Rho kinase is a well-known target for active Rho, and inactivating Rho kinase has the same effect as inactivating Rho, at least in terms of neurite or axon growth (Kimura and Schubert (1992) Journal of Cell Biology. 116:777-783, Keino-Masu, et al. (1996) Cell. 87:175-185, Matsui, et al. (1996) EMBO J. 15:2208-2216, Matsui, et al. (1998) J. Cell Biol. 140:647-657, Ishizaki (1997) FEBS Lett. 404: 118-124), the biological activity that concerns this invention.
The C3 polypeptides of the present invention include biologically active fragments and analogues of C3; fragments encompass amino acid sequences having truncations of one or more amino acids, wherein the truncation may originate from the amino terminus, carboxy terminus, or from the interior of the protein. Fragments containing Glu(173) of C3 are included in this invention (Saito et al. 1995. FEBS Lett. 371-105). Analogues of the invention involve an insertion or a substitution of one or more amino acids. Fragments and analogues will have the biological property of C3 that is capable of inactivating Rho GTPase on Asn(41) on Rho. Also encompassed by the invention are chimeric polypeptides comprising C3 amino acid sequences fused to heterologous amino acid sequences. Said heterologous sequences encompass those which, when formed into a chimera with C3 retain one or more biological or immunological properties of C3. A host cell transformed or transfected with nucleic acids encoding C3 protein or C3 chimeric protein are also encompassed by the invention. Any host cell which produces a polypeptide having at least one of the biological properties of C3 may be used. Specific examples include bacterial, yeast, plant, insect or mammalian cells. In addition, C3 protein may be produced in transgenic animals. Transformed or transfected host cells and transgenic animals are obtained using materials and methods that are routinely available to one skilled in the art. Host cells may contain nucleic acid sequences having the full-length gene for C3 protein including a leader sequence and a C-terminal membrane anchor sequence (see below) or, alternatively, may contain nucleic acid sequences lacking one or both of the leader sequence and the C-terminal membrane anchor sequence. In addition, nucleic acid fragments, variants and analogues which encode a polypeptide capable of retaining the biological activity of C3 may also be resident in host expression systems.
C3 is produced as a 26 kDa protein. The full length C3 protein inactivates Rho by ADP-ribosylating asparagine 41 of Rho A (Han et al. (2001) J. Mol. Biol. 305: 95). Truncated, elongated or altered C3 proteins or C3-derived peptides that retain the ability to ribosylate Rho are included in this invention and can be used to make fusion proteins. The crystal structure of C3 has been determined giving insight to elements of the C3 protein that could be changed without affecting ribosylating activity (Han et al. (2001) J. Mol. Biol. 305: 95).
The Rho antagonist that is a recombinant proteins can be made according to methods present in the art. The proteins of the present invention may be prepared from bacterial cell extracts, or through the use of recombinant techniques. In general, C3 proteins according to the invention can be produced by transformation (transfection, transduction, or infection) of a host cell with all or part of a C3-encoding DNA fragment in a suitable expression vehicle. Suitable expression vehicles include: plasmids, viral particles, and phages. For insect cells, baculovirus expression vectors are suitable. The entire expression vehicle, or a part thereof, can be integrated into the host cell genome. In some circumstances, it is desirable to employ an inducible expression vector.
Those skilled in the field of molecular biology will understand that any of a wide variety of expression systems can be used to provide the recombinant protein. The precise host cell used is not critical to the invention. The C3 and C3-like proteins may be produced in a prokaryotic host (e.g., E. coli or B. subtilis ) or in a eukaryotic host (e.g., Saccharomyces or Pichia ; mammalian cells, e.g., COS, NIH 3T3, CHO, BHK, 293, or HeLa cells; or insect cells).
To determine the relative and effective Rho antagonist activity of the compositions of this invention, a tissue culture bioassay system can be used. A fusion protein such as C3APLT at a concentration range of from about 0.01 to about 10 μg/ml (microgram per milligram) is useful and is not toxic to cells.
Proteins and polypeptides may also be produced by plant cells. For plant cells viral expression vectors (e.g., cauliflower mosaic virus and tobacco mosaic virus) and plasmid expression vectors (e.g., Ti plasmid) are suitable. Such cells are available from a wide range of sources (e.g., the American Type Culture Collection, Rockland, Md.). The methods of transformation or transfection and the choice of expression vehicle will depend on the host system selected.
The host cells harboring the expression vehicle can be cultured in conventional nutrient media adapted as need for activation of a chosen gene, repression of a chosen gene, selection of transformants, or amplification of a chosen gene. One expression system is the mouse 3T3 fibroblast host cell transfected with a pMAMneo expression vector (Clontech, Palo Alto, Calif.). pMAMneo provides an RSV-LTR enhancer linked to a dexamethasone-inducible MMTV-LTR promotor, an SV40 origin of replication which allows replication in mammalian systems, a selectable neomycin gene, and SV40 splicing and polyadenylation sites. DNA encoding a C3 or C3-like protein would be inserted into the pMAMneo vector in an orientation designed to allow expression. The recombinant C3 or C3-like protein would be isolated as described below. Other preferable host cells that can be used in conjunction with the pMAMneo expression vehicle include COS cells and CHO cells (ATCC Accession Nos. CRL 1650 and CCL 61, respectively).
C3 polypeptides can be produced as fusion proteins. For example, expression vectors may be used to create lacz fusion proteins. The pGEX vectors can be used to express foreign polypeptides as fusion proteins with glutathione S-transferase (GST). In general, such fusion proteins are soluble and can be easily purified from lysed cells by adsorption to glutathione-agarose beads followed by elution in the presence of free glutathione. The pGEX vectors are designed to include thrombin or factor Xa protease cleavage sites so that the cloned target gene product can be released from the GST moiety. Another strategy to make fusion proteins is to use the His tag system.
In an insect cell expression system, Autographa californica nuclear polyhedrosis virus AcNPV), which grows in Spodoptera frugiperda cells, is used as a vector to express foreign genes. A C3 coding sequence can be cloned individually into non-essential regions (for example the polyhedrin gene) of the virus and placed under control of an AcNPV promoter, e.g., the polyhedrin promoter. Successful insertion of a gene encoding a C3 or C3-like protein (polypeptide) will result in inactivation of the polyhedrin gene and production of non-occluded recombinant virus (i.e., virus lacking the proteinaceous coat encoded by the polyhedrin gene). These recombinant viruses are then used to infect Spodoptera frugiperda cells in which the inserted gene is expressed (see, Lehmann et al for an example of making recombinant MAG protein).
In mammalian host cells, a number of viral-based expression systems can be utilized. In cases where an adenovirus is used as an expression vector, the C3 nucleic acid sequence can be ligated to an adenovirus transcription/translation control complex, e.g., the late promoter and tripartite leader sequence. This chimeric gene can then be inserted into the adenovirus genome by in vitro or in vivo recombination. Insertion into a non-essential region of the viral genome (e.g., region E1 or E3) will result in a recombinant virus that is viable and capable of expressing a C3 gene product in infected hosts.
Specific initiation signals may also be required for efficient translation of inserted nucleic acid sequences. These signals include the ATG initiation codon and adjacent sequences. In cases where an entire native C3 gene or cDNA, including its own initiation codon and adjacent sequences, is inserted into the appropriate expression vector, no additional translational control signals may be needed. In other cases, exogenous translational control signals, including, perhaps, the ATG initiation codon, must be provided. Furthermore, the initiation codon must be in phase with the reading frame of the desired coding sequence to ensure translation of the entire insert. These exogenous translational control signals and initiation codons can be of a variety of origins, both natural and synthetic. The efficiency of expression may be enhanced by the inclusion of appropriate transcription enhancer elements, transcription terminators.
In addition, a host cell may be chosen which modulates the expression of the inserted sequences, or modifies and processes the gene product in a specific, desired fashion. Such modifications (e.g., glycosylation) and processing (e.g., cleavage) of protein products may be important for the function of the protein. Different host cells have characteristic and specific mechanisms for the post-translational processing and modification of proteins and gene products. Appropriate cell lines or host systems can be chosen to ensure the correct modification and processing of the foreign protein expressed. To this end, eukaryotic host cells that possess the cellular machinery for proper processing of the primary transcript, glycosylation, and phosphorylation of the gene product can be used. Such mammalian host cells include, but are not limited to, CHO, VERO, BHK, HeLa, COS, MDCK, 293, 3T3, W138, and in particular, choroid plexus cell lines.
Alternatively, a C3 protein can be produced by a stably-transfected mammalian cell line. A number of vectors suitable for stable transfection of mammalian cells are available to the public; methods for constructing such cell lines are also publicly available. In one example, cDNA encoding the C3 protein may be cloned into an expression vector that includes the dihydrofolate reductase (DHFR) gene. Integration of the plasmid and, therefore, the C3 or C3-like protein-encoding gene into the host cell chromosome is selected for by including 0.01-300 μM (micromole) methotrexate in the cell culture medium (as described in Ausubel et al., supra). This dominant selection can be accomplished in most cell types. Recombinant protein expression may be increased by DHFR-mediated amplification of the transfected gene. Methods for selecting cell lines bearing gene amplifications are known in the art; such methods generally involve extended culture in medium containing gradually increasing levels of methotrexate. DHFR-containing expression vectors commonly used for this purpose include pCVSEII-DHFR and pAdD26SV(A). Any of the host cells described above or, preferably, a DHFR-deficient CHO cell line (e.g., CHO DHFR cells, ATCC Accession No. CRL 9096) are among the host cells preferred for DHFR selection of a stably-transfected cell line or DHFR-mediated gene amplification.
A number of other selection systems may be used, including but not limited to the herpes simplex virus thymidine kinase, hypoxanthine-guanine phosphoribosyltransferase, and adenine phosphoribosyltransferase genes can be employed in tk, hgprt, or aprt cells, respectively. In addition, gpt, which confer resistance to mycophenolic acid; neo, which confers resistance to the aminoglycoside G-418; and hygro, which confers resistance to hygromycin may be used.
Alternatively, any fusion protein can be readily purified by utilizing an antibody specific for the fusion protein being expressed. For example, a system described in Janknecht et al. (1981) Proc. Natl. Acad. Sci. USA 88, 8972, allows for the ready purification of non-denatured fusion proteins expressed in human cell lines. In this system, the gene of interest is subcloned into a vaccinia recombination plasmid such that the gene's open reading frame is translationally fused to an amino-terminal tag consisting of six histidine residues. Extracts from cells infected with recombinant vaccinia virus are loaded onto Ni2+nitriloacetic acid-agarose columns, and histidine-tagged proteins are selectively eluted with imidazole-containing buffers.
Alternatively, C3, C3-like protein or a portion (fragment) thereof, can be fused to an immunoglobulin Fc domain. Such a fusion protein can be readily purified using a protein A column.
To test Rho antagonists for activity, a tissue culture bioassay system was used. This bioassay is used to define activity of Rho antagonists that will be effective in promoting axon regeneration in spinal cord injury, stroke or neurodegenerative disease.
Neurons do not grow neurites on inhibitory myelin substrates. When neurons are placed on inhibitory substrates in tissue culture, they remain rounded. When an effective Rho antagonist is added, the neurons are able to grow neurites on myelin substrates. The time that it takes for neurons to growth neurites upon the addition of a Rho antagonist is the same as if neurons had been plated on growth permissive substrate such as laminin or polylysine, typically 1 to 2 days in cell culture. The results can be scored visually. If needed, a quantitative assessment of neurite growth can be performed. This involved measuring the neurite length in a) control cultures where neurons are plated on myelin substrates and left untreated b) in positive control cultures, such as neurons plated on polylysine c) or treating cultures with different concentrations of the test antagonist.
To test C3 in tissue culture, it has been found that the best concentration is 25-50 ug/ml. (Lehmann et al, 1999. J. Neurosci. 19: 7537-7547; Jin & Strittmatter, 1997. J. Neurosci. 17: 6256-6263). Thus, high concentrations of this Rho antagonist are needed as compared to the growth factors used to stimulate neurite outgrowth. Growth factors, such as nerve growth factor (NGF) are used at concentrations of 1-100 ng/ml in tissue culture. However, growth factors are not able to overcome growth inhibition by myelin. Our tissue culture experiments are all performed in the presence of the growth factor BDNF for retinal ganglion cells, or NGF for PC-12 cells. When growth factors have been tested in vivo, typically the highest concentrations possible are used, in the ug/ml range. Also they are often added to the CNS with the use of pumps for prolonged delivery (e.g. Ramer et al, supra). For in vivo experiments the highest concentrations possible was used when working with C3 stored as a frozen 1 mg/ml solution.
The Rho antagonist C3 is stable at 37° C. for at least 24 hours. The stability of C3 was tested in tissue culture with the following experiment. The C3 was diluted in tissue culture medium, left in the incubator at 37° C. for 24 hours, then added to the bioassay system described above, using retinal ganglion cells as the test cell type. These cells were able to extend neurites on inhibitory substrates when treated with C3 stored for 24 hours at 37° C. Therefore, the minimum stability is 24 hours. This is in keeping with the stability projection based on amino acid composition (see sequence data, below).
A compound can be confirmed as a Rho antagonist in one of the following ways:
a. Cells are cultured on a growth inhibitory substrate as above, and exposed to the candidate Rho antagonist; b. Cells of step a) are homogenized and a pull-down assay is performed. This assay is based on the capability of GST-Rhotektin to bind to GTP-bound Rho. Recombinant GST-Rhotektin or GST rhotektin binding domain (GST-RBD) is added to the cell homogenate made from cells cultured as in a). It has been found that inhibitory substrates activate Rho, and that this activated Rho is pulled down by GST-RBD. Rho antagonists will block activation of Rho, and therefore, an effective Rho antagonist will block the detection of Rho when cell are cultured as described by a) above; or c. An alternate method for this pull-down assay would be to use the GTPase activating protein, Rho-GAP as bait in the assay to pull down activated Rho, as described (Diekmann and Hall, 1995. In Methods in Enzymology Vol. 256 part B 207-215).
Another method to confirm that a compound is a Rho antagonist is as follows: When added to living cells antagonists that inactivate Rho by ADP-ribosylation of the effector domain can be identified by detecting a molecular weight shift in Rho (Lehmann et al, 1999 supra). The molecular weight shift can be detected after treatment of cells with Rho antagonist by homogenizing the cells, separating the proteins in the cellular homogenate by SDS polyacrylamide gel electrophoresis. The proteins are transferred to nitrocellulose paper, then Rho is detected with Rho-specific antibodies by a Western blotting technique.
Another method to confirm that compound is a Rho-kinase antagonist is as follows:
a. Recombinant Rho kinase tagged with myc epitope tag, or a GST tag or any suitable tag is expressed in Hela cells or another suitable cell type by transfection; b. The kinase is purified from cell homogenates by immunoprecipitation using antibodies directed against the specific tag (e.g., myc tag or the GST tag); and c. The recovered immunoprecipitates from b) are incubated with [ 32 P] ATP and histone type 2 as a substrate in the presence or absence of the Rho kinase inhibitor. In the absence of Rho kinase inhibitor activity, the Rho kinase phosphorylated histone. In the presence of Rho kinase inhibitor the phosphorylation activity of Rho kinase (i.e. phosphorylation of histone) is blocked, and as such identified the compound as a Rho kinase antagonist.
Turning now to the transport side of the conjugates of the present invention, known methods are available to add transport sequences that allow proteins to penetrate into the cell; examples include membrane translocating sequence (Rojas (1998) 16: 370-375), Tat-mediated protein delivery (Vives (1997) 272: 16010-16017), polyargine sequences (Wender et al. 2000, PNAS 24: 13003-13008) and antennapedia (Derossi (1996) 271: 18188-18193). Examples of known transport agents, moities, subdomains and the like are also shown for example in Canadian patent document no. 2,301,157 (conjugates containing homeodomain of antennapedia) as well as in U.S. Pat. Nos. 5,652,122, 5,670,617, 5,674,980, 5,747,641, and 5,804,604 (conjugates containing amino acids of Tat HIV protein (hereinafter Tat HIV protein is sometimes simply referred to as Tat); the entire contents of each of these patent documents is incorporated herein by reference.
A 16 amino acid region of the third alpha-helix of antennapedia homeodomain has been shown to enable proteins (made as fusion proteins) to cross cellular membranes (PCT international publication number WO 99/11809 and Canadian application No.: 2,301,157 (Crisanti et al,) incorporated herein as references). Here we have generated fusion-proteins comprising C3 and having an antennapedia homeodomain sequence located at the carboxy-terminal end of the fusion-protein. The biological activity (e.g., promoting axon growth) of these fusion proteins was demonstrated on primary mammalian cells such as neurons. Similarly, HIV Tat protein was shown to be able to cross cellular membranes (Frankel A. D. et al., Cell, 55: 1189). We have shown here using a sequence spanning amino acid 27 to 72 of HIV Tat, that Tat-mediated delivery of biologically active C3 protein is possible in neuronal cells and more specifically, in primary neuronal cells.
In addition to HIV Tat and antennapedia-mediated transport of C3 proteins and analogs, new transport sequences (i.e., transport polypeptide moiety, transport agent region, etc.) are presented herein.
Several receptor-mediated transport strategies have been used to try and improve function of ADP ribosylases: these methods include fusing C2 and C3 sequences (Wilde, et al. (2001) 276: 9537-9542.) and use of receptor-mediated transport with the diphtheria toxin receptor (Aullo, et al. (1993) 12: 921-31; Boquet, P. et al. (1995) Meth. Enzymol. 256: 297-306).). These methods have not been demonstrated to dramatically increase the potency of C3. Moreover, these proteins require receptor-mediated transport. This means that the cells must express the receptor, and must express sufficient quantities of the receptor to significantly improve transport. Moreover, when C3 enters the cell by endocytosis, it will be locked within a membrane compartment, and therefore most of it will not be available to inactivate Rho. In the case of diphtheria toxin, not all cells express the appropriate receptor, limiting its potential use. The clinical importance for any of these has not been tested or shown. A C2/C3 fusion protein has also been made to try and improve the effectiveness of C3. In this case, the addition of a C211 binding protein to the tissue culture medium is needed, along with the C2-C3 fusion toxin to allow uptake of C3 by receptor-mediated endocytosis (Barthe et al. (1998) Infection and Immunity 66:1364). The disadvantage of this system is that much of the C3 in the cell will be restrained within a membrane compartment. More importantly, two different proteins must be added separately for transport to occur (Wahl et al. 2000. J. Cell Biol. 149:263), which make this system difficult to apply to in vivo for treatment of disease. Moreover, none of the methods to inactivate Rho with C3 or C3 analogues (C3-like protein) have been demonstrated to be sufficient to overcome growth inhibition in tissue culture, or to promote recovery after CNS damage in vivo.
One strategy which may be used in accordance with the present invention is to exploit the antennapedia homeodomain that is able to transport proteins across the plasma membrane by a receptor-independent mechanism (Derossi (1996) 271: 18188-18193); an alternate strategy is to exploit Tat-mediated delivery (Vives (1997) 272: 16010-16017, Fawell (1994) 91: 664-668, Frankel (1988) 55: 1189-1193).
The Antennapedia strategy has been used for protein translocation into neurons (Derossi (1996) 271: 18188-18193). Antennapedia has, for example, been used to transport biotin-labeled peptides in order to demonstrate the efficacy of the technique; see U.S. Pat. No. 6,080,724 (the entire contents of this patent are incorporated herein by reference). Antennapedia enhances growth and branching of neurons in vitro (Bloch-Gallego (1993) 120: 485-492). Homeoproteins are transcription factors that regulate development of body organization, and antennapedia is a Drosophila homeoprotein. Tat on the other hand is a regulatory protein from human immunodeficiency virus (HIV). It is a highly basic protein that is found in the nucleus and can transport reporter genes into cell. Moreover, Tat-linked proteins can penetrate cells after intraperitoneal injection, and it can even cross the blood brain barrier to enter cells within the brain (Schwarze, et al. (1999) 285: 1569-72).
Other transport sequences that have been tested in other contexts, (i.e., to show that they work through the use of reporter sequences), are known. One transport peptide, a 12 mer, AAVLLPVLLAAP (SEQ ID NO:51), is rich in proline. It was made as a GST-MTS fusion protein and is derived from the h region of the Kaposi FGF signal sequence (Royas et al. 1998 Nature Biotech. 16: 370-375. Another example is the sperm fertiline alpha peptide, HPIQIAAFLARIPPISSIGTCILK (SEQ ID NO:52) (This is reviewed in Pecheur, J. Sainte-Marie, A. Bienvenuie, D. Hoekstra. 1999. J. Membrane Biol. 167: 1-17). It must be noted however that the alpha helix-breaking propensity of proline (Pro) residues is not a general rule, since the putative fusion peptide of sperm fertilin alpha displays a high alpha helical content in the presence of liposomes. However, the Pro-Pro sequence is required for efficient fusion properties of fertilin. The C3APLT fusion protein that we tested fits the requirement of having a two prolines for making an effective transport peptide. Therefore, proline-rich sequences and random sequences that have helix-breaking propensity that act as effective transporters would also be effective if fused to C3.
In the context of axon growth on inhibitory substrates, axon regeneration after injury, or axon regeneration in the brain or spinal cord, no method using these transport sequences has been devised. In particular, it should be noted that the ability of antennapedia to enhance growth was tested with neurons placed on laminin-coated coverslips. Laminin supports axon growth and overrides growth inhibition (David, et al. (1995) 42: 594-602) thus, it is not a suitable substrate to test the potential for regeneration. There is an enormous wealth of literature over the last 20 years on substances that promote axon growth under such favorable tissue culture conditions, but none of these has lead to clinical advances in the treatment of spinal cord injury. The effect of antennapedia was shown to act as similar to a growth factors. Growth factors do not overcome growth inhibition by CNS growth inhibitory substrates (Lehmann, et al. (1999) 19: 7537-7547, Cai, et al. (1999) 22: 89-101). Growth factors applied in vivo do not support regeneration, only sprouting (Schnell, et al. (1994) 367: 170-173).
The transport sequence may be added to the N-terminal (amino-terminal) sequence of the C3 protein. Alternatively, the transport sequence may be added on the C-terminal (carboxy-terminal) end of the C3 protein; because the C-terminal is already quite basic, this should enhance further the transport properties. This is likely one of the reasons that C3APLT shows activity in addition to its basic charge and the proline-rich sequences.
The new chimeric C3 may be used to treat spinal cord injury to promote functional repair. We have demonstrated that both C3APLT and C3APS can overcome growth inhibition on complex inhibitory substrates that include myelin and mixed chondroitin sulfate proteoglycans. Further, we demonstrate that C3APLT can promote functional recovery after application to injured spinal cord in adult mice. The new chimeric protein may be used to promote axon regeneration and reduce scarring after CNS injury. Scarring is a barrier to nerve regeneration.
The advantage of the new chimeric C3 is the ability to treat the injured axons after a significant delay between the injury and the treatment. Also, the new recombinant protein may be useful in the treatment of chronic injury. The chimeric C3 can also be used to treat neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease where penetration of the Rho antagonist to the affected neuronal population is required for effective treatment. The chimeric C3 (fusion proteins) will also be of benefit for the treatment of stroke and traumatic brain injury. Moreover, much evidence suggests efficacy in the treatment of cancer cell migration. Rho antagonists are also useful in the treatment of disease involving smooth muscle, such as vascular disease, hypertension, asthma, and penile dysfunction.
For treatment of spinal cord injury, the conjugate Rho antagonists of the present invention may be used in conjunction with cell transplantation. Many different cell transplants have been extensively tested for their potential to promote regeneration and repair, including, but not restricted to, Schwann cells, fibroblasts modified to express growth factors, fetal spinal cord transplants, macrophages, embryonic or adult stem cells, and olfactory ensheathing glia. C3 fusion proteins may be used in conjunction with neurotrophins, apoptosis inhibitors, or other agents that prevent cell death. They may be used in conjunction with cell adhesion molecules such as L1, laminin, and artificial growth matrices that promote axon growth. The chimeric C3 constructs of the present invention may also be used in conjunction with the use of antibodies that block growth inhibitory protein substrates to promote axon growth. Examples of such antibody methods are the use of IN-1 or related antibodies (Schnell and Schwab (1990) 343: 269-272) or through the use of therapeutic vaccine approaches (Huang (1999) 24: 639-647).
The compositions of this invention can be administered to the eye, for example by intravenous delivery to the eye, by implantation of a depot comprising a composition of the invention, by injection into the eye or into tissues proximal to the eye.
The bulb of the eye is imbedded in the fat of the orbit from which it is separated by a thin membrane, the fascia bulbi, which envelops the bulb from the optic nerve to the ciliary region. The smooth inner surface of the facia is separated from the outer surface of the sclera by the periscleral lymph space which is continuous with the subdural and subarachnoid cavities. The fascia is perforated by the ciliary vessels and nerves, and fuses with the sheath of the optic nerve and with the sclera around the entrance of the optic nerve. The optic nerve enters its eyeball about 3 millimeters to the nasal side and a little below the level of the central point of the posterior curvature of the eye. Optic nerve fiber growth is centripetal, and during their formation, most optic nerve fibers grow backward into the optic stalk from nerve cells of the retina, but some optic nerve fibers extend and are derived from nerve cells in the brain. The optic nerve fiber layer is composed principally of axons of the retinal ganglion cells that project to the brain through the optic nerve and the supporting glial cells.
The outer layer of the eye comprises the sclera and cornea. The sclera is an opaque, firm membrane, as much as 1 millimeter thick, and constitutes the posterior five-sixths of the eye. The sclera is formed of white fibrous tissue intermixed with fine elastic fibers; flattened connective-tissue corpuscles, some of which are pigmented, are contained in cell spaces between the fibers. Compositions of this invention can be administered for example by injection into and/or through the sclera or by formation of a depot proximal to and/or in the sclera, preferably in the posterior of the eye.
The inner surface of the sclera is separated from the outer surface of the choroid by an extensive lymph space or spatium perichorioideale which is traversed by fine cellular tissue, the lamina suprachorioidea. The sclera is pierced by the optic nerve, and is continuous through the fibrous sheath of this nerve with the dura mater. Where the optic nerve passes through the sclera, the sclera forms a thin cribriform lamina, the lamina cribrosa sclerx. Minute orifices in this lamina serve for the transmission of nervous filaments, and the retinal ganglion cell axons distal to the lamina cribrosa are myelinated by oligodedrocytes. The fibrous septa dividing them from one another are continuous with the membranous processes which separate the bundles of nerve fibers. One of these openings, larger than the rest, occupies the center of the lamina; it transmits the central artery and vein of the retina. Around the entrance of the optic nerve are numerous small apertures for the transmission of the ciliary vessels and nerves. About midway between this entrance and the sclerocorneal junction are four or five large apertures for the transmission of veins, the venæ vorticosæ. Compositions of this invention can be administered, for example by injection or perfusion or from a depot such as an implanted matrix comprising a composition of the invention, into a blood vessel which delivers blood to the retina, preferably to the region proximal to the macula.
The vascular tunic of the eye comprises the choroid, the ciliary body, and the iris. The choroid invests the posterior five-sixths of the bulb of the eye proximal to the retina, and extends forward to the ora serrata of the retina. The ciliary body connects the choroid to the circumference of the iris.
The choroid comprises a thin spongy layer between the sclera and the retina; the choroid is filled with blood vessels. The choroid is a thin, highly vascular, dark brown membrane investing the posterior five-sixths of the globe of the eye; it is pierced behind by the optic nerve, and in this situation is firmly adherent to the sclera. It is thicker behind than in front. Its outer surface is loosely connected by the lamina suprachorioidea with the sclera; its inner surface is attached to the pigmented layer of the retina. Compositions of this invention can be administered, for example by injection or perfusion or from a depot such as an implanted matrix comprising a composition of the invention, into a blood vessel which delivers blood to the choroid, preferably to the region proximal to the macula.
The choroid consists mainly of a dense capillary plexus, and of small arteries and veins carrying blood to and returning it from this plexus. On its external surface is a thin membrane, the lamina suprachorioidea, composed of delicate non-vascular lamellæ. Each lamella consists of a network of fine elastic fibers among which are branched pigment cells. The spaces between the lamellæ are lined by endothelium, and open freely into the perichoroidal lymph space, which communicates with the periscleral space by the perforations in the sclera through which the vessels and nerves are transmitted. Internal to this lamina is the choroid proper which consists of two layers: an outer layer, composed of small arteries and veins, with pigment cells interspersed between them; and an inner layer, consisting of a capillary plexus. The outer layer, or lamina vasculosa, consists, in part, of the larger branches of the short ciliary arteries which run forward between the veins before they bend inward to end in capillaries. The venæ vorticosæ is formed principally of veins which converge to four or five equidistant trunks, which pierce the sclera about midway between the sclero-corneal junction and the entrance of the optic nerve. Interspersed between the vessels are dark star-shaped pigment cells, the processes of which, communicating with those of neighboring cells, form a delicate network or stroma, which toward the inner surface of the choroid loses its pigmentary character. The inner layer of the choroid, or lamina choriocapillaris, consists of an exceedingly fine capillary plexus formed by the short ciliary vessels. This network is closer and finer in the posterior than in the anterior part of the choroid. About 1.25 centimeters behind the cornea its meshes become larger, and are continuous with those of the ciliary processes. These two laminæare connected by a stratum intermedium consisting of fine elastic fibers. On the inner surface of the lamina choriocapillaris is a very thin, structureless or faintly fibrous membrane, the lamina basalis, which is closely connected with the stroma of the choroid, and separates it from the pigmentary layer of the retina.
The retina is a nervous tissue in the eye, and contains millions of rod and cone cells which convert light energy into chemical electrical or neural signals which are sent to the brain via the optic nerve. The outer surface of the retina is in contact with the choroid. The inner surface of the retina is in contact with the hyaloid membrane of the vitreous body. The retina is continuous with the optic nerve, and gradually diminishes in thickness from the posterior of the eye forward, extending nearly as far as the ciliary body, where it appears to end in a jagged margin, the ora serrata. At the ora serrata, the nervous tissues of the retina end, but a thin prolongation of the membrane extends forward over the back of the ciliary processes and iris, forming the pars ciliaris retinæ and pars iridica retina. The retina is soft, semitransparent, and purple in tint due to the presence of rhodopsin.
The macula lutea resides at the center of the posterior part of the retina at a point corresponding to the axis of the eye where the sense of vision is most acute, i.e., where finer or higher resolution visual detail and visual focus occurs to provide the greatest degree of visual acuity. The macula comprises an oval yellowish area in which the color is deepest toward the center, and is about 6 by 7 millimeters (mm) in size. The fovea centralis comprises a central depression in the macula, wherein the retina is exceedingly thin. The fovea is about 1.5 mm in diameter and located just behind the macula, where the highest concentration of cone photoreceptors are concentrated. Light rays are focused in the eye by the lens onto the fovea for straight ahead vision and fine detail.
The ganglionic layer (retinal ganglion layer (RGC layer)) of the macula lutea consists of several strata of cells. There are no rod cells, but only cone cells which are longer and narrower than in other parts of the retina. In the outer nuclear layer there are only cone-cells, the processes of which are very long and arranged in curved lines. The layers of the fovea centralis comprise cone cells plus the outer nuclear layer, the cone-fibers of which are almost horizontal in direction, plus a thin inner plexiform layer.
About 3 millimeters to the nasal side of the macula lute is the entrance of the optic nerve, i.e., the optic disk, the circumference of which is slightly raised to form an eminence or colliculus nervi optici; the arteria centralis retinæ pierces the center of the disk. This part of the surface of the retina, termed the blind spot is insensitive to light. The optic nerve and the central retinal blood vessels enter the back of the eye at the disc comprising the blind spot.
The arteria centralis retina and its accompanying vein pierce the optic nerve, and enter the bulb of the eye through the porus opticus. The artery immediately bifurcates into an upper and a lower branch, and each of these again divides into a medial or nasal and a lateral or temporal branch, which at first run between the hyaloid membrane and the nervous layer before entering the latter to pass forward, dividing dichotomously. From these branches a minute capillary plexus is given off, which does not extend beyond the inner nuclear layer. The macula receives two small branches, which are the superior and inferior macular arteries, from the temporal branches and small arterial twigs directly from the central artery. These do not reach as far as the fovea centralis, which has no blood vessels. The branches of the arteria centralis retina do not anastomose with each other, i.e., they are terminal arteries.
The nervous structures of the retina are supported by a series of non-nervous or sustentacular fibers and the retina consist of seven layers: the stratum opticum or fiber layer which is composed of axons of the retinal ganglion cells (RGC); the ganglionic layer or RGC layer composed of cell bodies of RGCs and some displaced amacrine cells; the inner plexiform layer composed of dendrites of the RGCs and amacrine cells; the inner nuclear layer, or layer with cell bodies of the interneurons of the retina; the outer plexiform layer, a layer with dentrites; the outer nuclear layer composed of cell bodies of the photoreceptor cells; and the layer of rods and cones.
The stratum opticum is formed by the RGC axons that extend to the optic nerve. As the nerve fibers pass through the lamina cribrosa sclera toward the eye they lose their myelinated sheaths and are continued onward through the choroid and retina as simple unmylinated axons. When they reach the internal surface of the retina they radiate from their point of entrance over this surface grouped in bundles, and in many places are arranged in plexuses. Most of the fibers are centripetal, and are the direct continuations of the axis-cylinder processes of the cells of the RGC layer, but a few of them are centrifugal and ramify in the inner plexiform and inner nuclear layers, where they end in enlarged extremities.
The RGC layer consists of a single layer of large ganglion cells, except in the macula lutea, where there are several strata of ganglion cells. The ganglion cells rest on and each sends off a prolonged axon into the stratum opticum. Numerous dendrites extend into the inner plexiform layer, where they branch and form flattened arborizations at different levels. The ganglion cells vary in size, and the dendrites of the smaller ones arborize in the inner plexiform layer as soon as they enter it; while the dendrites of the larger cells ramify close to the inner nuclear layer.
The inner plexiform layer is made up of a dense reticulum of minute fibrils formed by the interlacement of the dendrites of the ganglion cells with those of the cells of the inner nuclear layer; within this reticulum a few branched spongioblasts are sometimes imbedded.
The inner nuclear layer or layer of inner granules (cells) comprises three varieties of closely packed cells: bipolar cells, horizontal cells, and amacrine cells. The bipolar cells are the most numerous, and are round or oval in shape. Each is prolonged into an inner and an outer process. They are divisible into rod bipolars and cone bipolars. The inner processes of the rod bipolars run through the inner plexiform layer and arborize around the bodies of the cells of the ganglionic layer; their outer processes end in the outer plexiform layer in tufts of fibrils around the ends of the inner processes of the rod cells. The inner processes of the cone bipolars ramify in the inner plexiform layer in contact with the dendrites of the ganglionic cells. The horizontal cells have flattened cell bodies and lie in the outer part of the inner nuclear layer. Their dendrites divide into numerous branches in the outer plexiform layer, while their axons run horizontally for some distance and finally ramify in the same layer. The amacrine cells are found in the inner part of the inner nuclear layer. Their dendrites undergo extensive ramification in the inner plexiform layer.
The outer plexiform layer is thinner than the inner plexiform layer, and consists of a dense network of minute fibrils derived from the processes of the horizontal cells of the preceding layer. The outer processes of the rod and cone bipolar cells, which ramify in it, form arborizations around the enlarged ends of the rod fibers and with the branched foot plates of the cone fibers.
The outer nuclear layer, like the inner nuclear layer, contains cell bodies which are of two kinds: rod and cone cells, which are respectively connected with the rods and cones of the next layer. The rods are much more numerous than the cones, and are placed at different levels throughout the layer. Prolonged from either extremity of each rod cell is a fine process, one of which is continuous with a single rod of the layer of rods and cones, while the other ends in the outer plexiform layer in an enlarged extremity, and is imbedded in the tuft into which the outer processes of the rod bipolar cells break up. The cones are close to the membrana limitans externa through which they are continuous with the cones of the layer of rods and cones. From one extremity of the cone a thick process passes into the outer plexiform layer where it expands into a pyramidal enlargement or foot plate, from which are given off numerous fine fibrils, that come in contact with the outer processes of the cone bipolar cells.
The layer of rods and cones comprises rods and cones (photoreceptor cells), the former being much more numerous than the latter except in the macula lutea. The rods are cylindrical, of nearly uniform thickness, and are arranged perpendicularly to the surface. Each rod consists of two segments, an outer and inner, of about equal lengths. The outer segment is marked by transverse striæ, and tends to break up into a number of thin disks superimposed on one another. The deeper part of the inner segment is granular; its more superficial part presents a longitudinal striation, being composed of fine, highly refracting fibrils. Rhodopsin is found only in the outer segments. The cones are conical shaped, with their broad ends resting upon the membrana limitans externa, and the narrow extremity being turned to the choroid. Like the rods, each is made up of two segments, outer and inner; the outer segment is a short conical process, which, like the outer segment of the rod, exhibits transverse striæ. The inner segment resembles the inner segment of the rods in structure, presenting a superficial striated and deep granular part, but differs from it by being bulged out laterally and flask-shaped. The chemical and optical characters of the two portions are identical with those of the rods.
The term retinal cell can refer herein to any of the cell types that comprise the retina, such as retinal ganglion cells, amacrine cells, horizontal cells, bipolar cells, and photoreceptor cells including rods and cones, Muller glial cells, and retinal pigmented epithelium.
Advanced wet macular degeneration is a disease of the eye which comprises neovascularization of the choroid tissue underlying the photoreceptor cells in the macula. Macular degeneration, particularly in its advanced stages, is characterized by the pathological growth of new blood vessels in the choroid underlying the macula. Angiogenic blood vessels in the subretinal choroid can leak vision obscuring fluids, leading to blindness.
In one aspect, diseases of the eye which exhibit neovascularization proximal to the retina such as wet macular degeneration, retinitis pigmentosa, Stargardt's Disease, diabetic retinopathy, hypertensive retinopathy, and occlusive retinopathy can be treated to reduce the rate of neovascularization by administration of a composition of this invention comprising a fusion protein of this invention having angiogenesis inhibiting activity.
In another aspect, diseases of the eye which exhibit neovascularization proximal to the retina such as wet macular degeneration, retinitis pigmentosa, Stargardt's Disease, diabetic retinopathy, hypertensive retinopathy, and occlusive retinopathy can be treated to prevent or reduce the rate of photoreceptor cell death by administration of a composition of this invention comprising a fusion protein of this invention.
The compositions of the present invention when administered to the eye or to blood vessels that feed into the eye of a patient can be useful to treat diseases such as wet macular degeneration, retinitis pigmentosa, Stargardt's Disease, diabetic retinopathy, hypertensive retinopathy, and occlusive retinopathy by reducing the rate of formation of neovascularization and thereby slow the progress of the disease. The rate of neovascularization which occurs in such a disease in a patient is preferably reduced by administration of a fusion protein of this invention to at most 90%, more preferably to at most 50%, even more preferably to at most 25%, even more preferably to at most 10%, even more preferably to at most 5%, even more preferably to at most 1%, and most preferably to at most 0.1% of (times) the rate of neovascularization which occurs in such a disease in the absence of administration of a fusion protein of this invention (i.e., in an untreated patient).
The compositions of the present invention when administered to the eye or to blood vessels that feed into the eye of a patient can be useful to treat diseases such as wet macular degeneration, retinitis pigmentosa, Stargardt's Disease, diabetic retinopathy, hypertensive retinopathy, and occlusive retinopathy by reducing the rate of photoreceptor cell death and thereby slow the progress of the disease. The rate of photoreceptor cell death which occurs in such a disease in a patient is preferably reduced by administration of a fusion protein of this invention to at most 90%, more preferably to at most 50%, even more preferably to at most 25%, even more preferably to at most 10%, even more preferably to at most 5%, even more preferably to at most 1%, and most preferably to at most 0.1% of (times) the rate of photoreceptor cell death which occurs in such a disease in the absence of administration of a fusion protein of this invention (i.e., in an untreated patient).
Neovascularization proximal to the retina as a result of a disease, especially neovascularization proximal to the macula, can lead to photoreceptor cell death in the retina of a patient. Photoreceptor cell death in the retina can be produced as a consequence of a disease of the retina as a result of neovascularization as well as other mechanisms of cell death.
Advanced dry macular degeneration comprises the deposition of drusen and death of photoreceptor cells. The mechanism of drusen deposition is unknown, but exocytosis from cells is one likely mechanism of release into the extracellular space. Another embodiment of the present invention comprises the inhibition of drusen deposition and prevention of photoreceptor cell death by a cell-permeable fusion protein conjugate comprising a polypeptide comprising an amino acid sequence of a transport agent covalently linked to an amino acid sequence of an active agent, said amino acid sequence of said active agent consisting of ADP-ribosyl transferase C3 or a fragment thereof retaining an ADP-ribosyl transferase activity, said amino acid sequence of said transport agent facilitating cellular uptake of the active agent, for example a fusion protein such as C3APLT. In one aspect, the functional analog of a Clostridium botulinum C3 exotransferase unit comprises a protein exhibiting an ADP-ribosyl transferase activity in the range of 50% to 500% of the ADP-ribosyl transferase activity of Clostridium botulinum C3 exotransferase. Inactivation of Rho in a cell by a fusion protein of this invention after penetration of the cell membrane can block or inhibit exocytosis and thereby block or inhibit the release from the cell of cellular debris or cellular-derived material that can form drusen. A fusion protein of this invention can also prevent injury-induced cell death of a cell in the CNS.
Angiogenesis in neovascularization is the complex process of blood vessel formation. The process involves both biochemical and cellular events, including (1) activation of endothelial cells (ECs) by an angiogenic stimulus; (2) degradation of the extracellular matrix, invasion of the activated endothelial cells into the surrounding tissues, and migration toward the source of the angiogenic stimulus; and (3) proliferation and differentiation of endothelial cells to form new blood vessels (Folkman et al., 1991, J. Biol. Chem. 267:10931-10934).
The control of angiogenesis is a highly regulated process involving angiogenic stimulators and inhibitors. In healthy humans and animals, angiogenesis occurs under specific, restricted situations. For example, angiogenesis is normally observed in fetal and embryonal development, development and growth of normal tissues and organs, wound healing, and the formation of the corpus luteum, endometrium and placenta. Another embodiment of the present invention comprises the inhibition of angiogenesis by a cell-permeable fusion protein conjugate comprising a polypeptide comprising an amino acid sequence of a transport agent covalently linked to an amino acid sequence of an active agent, said amino acid sequence of said active agent consisting of ADP-ribosyl transferase C3 or a fragment thereof retaining an ADP-ribosyl transferase activity, said amino acid sequence of said transport agent facilitating cellular uptake of the active agent, for example a fusion protein such as C3APLT. In one aspect, the functional analog of a Clostridium botulinum C3 exotransferase unit comprises a protein exhibiting an ADP-ribosyl transferase activity in the range of 50% to 500% or more of the ADP-ribosyl transferase activity of Clostridium botulinum C3 exotransferase.
Another embodiment of the present invention comprises the inhibition of angiogenesis by an effective amount of a pharmaceutical composition comprising a cell-permeable fusion protein conjugate comprising a polypeptidic cell-membrane transport moiety and a Clostridium botulinum C3 exotransferase unit, or a functional analog thereof retaining an ADP-ribosyl transferase activity, for example a fusion protein such as C3APLT.
In one embodiment, this invention discloses a method of treatment of a disease of the eye selected from the group consisting of macular degeneration, retinitis pigmentosa, Stargardt's Disease, diabetic retinopathy, hypertensive retinopathy, and occlusive retinopathy, the method comprising administration to a patient in need of such treatment a therapeutically effective amount of a pharmaceutical composition comprising: a) a polypeptide consisting of SEQ ID NO:43 and; b) a pharmaceutically acceptable carrier. In one aspect of this embodiment, the carrier comprises a biological adhesive. In one aspect of this embodiment, the carrier comprises fibrin. In one aspect of this embodiment, the administration comprises injection.
In another embodiment, this invention discloses a method of treatment of a disease of the eye selected from the group consisting of macular degeneration, retinitis pigmentosa, Stargardt's Disease, diabetic retinopathy, hypertensive retinopathy, and occlusive retinopathy, the method comprising administration to a patient in need of such treatment a therapeutically effective amount of a pharmaceutical composition comprising: a) a polypeptide comprising an amino acid sequence of a transport agent covalently linked to an amino acid sequence of an active agent, said amino acid sequence of said active agent consisting of ADP-ribosyl transferase C3 or a fragment thereof retaining an ADP-ribosyl transferase activity, said amino acid sequence of said transport agent facilitating uptake of the active agent by a receptor-independent mechanism and being selected from the group consisting of a subdomain of HIV Tat protein, a homeodomain of antennapedia, and a Histidine tag, said polypeptide having ADP-ribosyl transferase activity, and; b) a pharmaceutically acceptable carrier. In one aspect of this embodiment, the amino acid sequence of the transport agent is at the carboxy-terminal end of said polypeptide and the amino acid sequence of the active agent is at the amino terminal end of said polypeptide. In one aspect of this embodiment, the carrier comprises a biological adhesive. In one aspect of this embodiment, the carrier comprises fibrin. In one aspect of this embodiment, the administration comprises injection.
In another embodiment, this invention discloses a method of treatment of a disease of the eye selected from the group consisting of macular degeneration, retinitis pigmentosa, Stargardt's Disease, diabetic retinopathy, hypertensive retinopathy, and occlusive retinopathy, the method comprising administration to a patient in need of such treatment a therapeutically effective amount of a pharmaceutical composition comprising: a) a polypeptide comprising an amino acid sequence of a transport agent covalently linked to an amino acid sequence of an active agent, said amino acid sequence of said active agent consisting of ADP-ribosyl transferase C3 or a fragment thereof retaining an ADP-ribosyl transferase activity, said amino acid sequence of said transport agent facilitating uptake of the active agent by a receptor-independent mechanism and being selected from the group consisting of SEQ ID NO: 21, SEQ ID NO: 26, SEQ ID NO: 31, SEQ ID NO: 44, SEQ ID NO: 45, SEQ ID NO: 46, SEQ ID NO: 47, and SEQ ID NO: 48, said polypeptide having ADP-ribosyl transferase activity, and; b) a pharmaceutically acceptable carrier. In one aspect of this embodiment, the amino acid sequence of the transport agent is at the carboxy-terminal end of said polypeptide and the amino acid sequence of the active agent is at the amino terminal end of said polypeptide. In one aspect of this embodiment, the carrier comprises a biological adhesive. In one aspect of this embodiment, the carrier comprises fibrin. In one aspect of this embodiment, the administration comprises injection.
In another embodiment, this invention discloses a method of treatment of a disease of the eye selected from the group consisting of macular degeneration, retinitis pigmentosa, Stargardt's Disease, diabetic retinopathy, hypertensive retinopathy, and occlusive retinopathy, the method comprising administration to a patient in need of such treatment a therapeutically effective amount of a pharmaceutical composition comprising: a) a polypeptide comprising an amino acid sequence of a transport agent covalently linked to an amino acid sequence of an active agent, said amino acid sequence of said active agent consisting of ADP-ribosyl transferase C3 or an amino acid sequence having at least 90% sequence identity with the amino acid sequence of SEQ ID NO: 43 and retaining ADP-ribosyl transferase activity, said amino acid sequence of said transport agent facilitating facilitating uptake of the active agent by a receptor-independent mechanism and being selected from the group consisting of a subdomain of HIV Tat protein, a homeodomain of antennapedia, and a Histidine tag, said polypeptide having ADP-ribosyl transferase activity, and; b) a pharmaceutically acceptable carrier. In one aspect of this embodiment, the carrier comprises a biological adhesive. In one aspect of this embodiment, the carrier comprises fibrin. In one aspect of this embodiment, the administration comprises injection. In one aspect of this embodiment, the amino acid sequence of the transport agent is at the carboxy-terminal end of said polypeptide and the amino acid sequence of the active agent is at the amino terminal end of said polypeptide.
In another embodiment, this invention discloses a method of treatment of a disease of the eye selected from the group consisting of macular degeneration, retinitis pigmentosa, Stargardt's Disease, diabetic retinopathy, hypertensive retinopathy, and occlusive retinopathy, the method comprising administration to a patient in need of such treatment a therapeutically effective amount of a pharmaceutical composition comprising: a) a polypeptide comprising an amino acid sequence of a transport agent covalently linked to an amino acid sequence of an active agent, said amino acid sequence of said active agent consisting of ADP-ribosyl transferase C3 or an amino acid sequence having at least 90% sequence identity with the amino acid sequence of SEQ ID NO: 43 and retaining ADP-ribosyl transferase activity, said amino acid sequence of said transport agent facilitating uptake of the active agent by a receptor-independent mechanism and being selected from the group consisting of SEQ ID NO: 21, SEQ ID NO: 26, SEQ ID NO: 31, SEQ ID NO: 44, SEQ ID NO: 45, SEQ ID NO: 46, SEQ ID NO: 47, and SEQ ID NO: 48, and; b) a pharmaceutically acceptable carrier. In one aspect of this embodiment, the carrier comprises a biological adhesive. In one aspect of this embodiment, the carrier comprises fibrin. In one aspect of this embodiment, the administration comprises injection. In one aspect of this embodiment, the amino acid sequence of the transport agent is at the carboxy-terminal end of said polypeptide and the amino acid sequence of the active agent is at the amino terminal end of said polypeptide.
In another embodiment, this invention discloses a method of inhibiting or substantially reducing the rate of subretinal neovascularization and proliferation of neovascular tissue, preventing drusen deposition and protecting retinal photoreceptors from cell death (i.e., reducing the rate of drusen deposition and reducing the rate of retinal photoreceptor cell death) in the eye of a mammalian host comprising administration to said host a therapeutically effective amount of a pharmaceutical composition comprising: a) a polypeptide consisting of SEQ ID NO:43 and; b) a pharmaceutically acceptable carrier. In one aspect of this embodiment, the carrier comprises a biological adhesive. In one aspect of this embodiment, the carrier comprises fibrin. In one aspect of this embodiment, the administration comprises injection.
In another embodiment, this invention discloses a method of inhibiting or substantially reducing the rate of subretinal neovascularization and proliferation of neovascular tissue preventing drusen deposition and protecting retinal photoreceptors from cell death (i.e., reducing the rate of drusen deposition and reducing the rate of retinal photoreceptor cell death) in the eye of a mammalian host comprising administration to said host a therapeutically effective amount of a pharmaceutical composition comprising: a) a polypeptide comprising an amino acid sequence of a transport agent covalently linked to an amino acid sequence of an active agent, said amino acid sequence of said active agent consisting of ADP-ribosyl transferase C3 or a fragment thereof retaining an ADP-ribosyl transferase activity, said amino acid sequence of said transport agent facilitating uptake of the active agent by a receptor-independent mechanism and being selected from the group consisting of a subdomain of HIV Tat protein, a homeodomain of antennapedia, and a Histidine tag, said polypeptide having ADP-ribosyl transferase activity, and; b) a pharmaceutically acceptable carrier.
In one aspect of this embodiment, the amino acid sequence of the transport agent is at the carboxy-terminal end of said polypeptide and the amino acid sequence of the active agent is at the amino terminal end of said polypeptide. In one aspect of this embodiment, the carrier comprises a biological adhesive. In one aspect of this embodiment, the carrier comprises fibrin. In one aspect of this embodiment, the administration comprises injection.
In another embodiment, this invention discloses a method of inhibiting or substantially reducing the rate of subretinal neovascularization and proliferation of neovascular tissue, preventing drusen deposition and protecting retinal photoreceptors from cell death (i.e., reducing the rate of drusen deposition and reducing the rate of retinal photoreceptor cell death) in the eye of a mammalian host comprising administration to said host a therapeutically effective amount of a pharmaceutical composition comprising: a) a polypeptide comprising an amino acid sequence of a transport agent covalently linked to an amino acid sequence of an active agent, said amino acid sequence of said active agent consisting of ADP-ribosyl transferase C3 or a fragment thereof retaining an ADP-ribosyl transferase activity, said amino acid sequence of said transport agent facilitating uptake of the active agent by a receptor-independent mechanism and being selected from the group consisting of SEQ ID NO: 21, SEQ ID NO: 26, SEQ ID NO: 31, SEQ ID NO: 44, SEQ ID NO: 45, SEQ ID NO: 46, SEQ ID NO: 47, and SEQ ID NO: 48, said polypeptide having ADP-ribosyl transferase activity, and; b) a pharmaceutically acceptable carrier. In one aspect of this embodiment, the amino acid sequence of the transport agent is at the carboxy-terminal end of said polypeptide and the amino acid sequence of the active agent is at the amino terminal end of said polypeptide. In one aspect of this embodiment, the carrier comprises a biological adhesive. In one aspect of this embodiment, the carrier comprises fibrin. In one aspect of this embodiment, the administration comprises injection.
In another embodiment, this invention discloses a method of inhibiting or substantially reducing the rate of subretinal neovascularization and proliferation of neovascular tissue, preventing drusen deposition and protecting retinal photoreceptors from cell death (i.e., reducing the rate of drusen deposition and reducing the rate of retinal photoreceptor cell death) in the eye of a mammalian host comprising administration to said host a therapeutically effective amount of a pharmaceutical composition comprising: a) a polypeptide comprising an amino acid sequence of a transport agent covalently linked to an amino acid sequence of an active agent, said amino acid sequence of said active agent consisting of ADP-ribosyl transferase C3 or an amino acid sequence having at least 90% sequence identity with the amino acid sequence of SEQ ID NO: 43 and retaining ADP-ribosyl transferase activity, said amino acid sequence of said transport agent facilitating facilitating uptake of the active agent by a receptor-independent mechanism and being selected from the group consisting of a subdomain of HIV Tat protein, a homeodomain of antennapedia, and a Histidine tag, said polypeptide having ADP-ribosyl transferase activity, and; b) a pharmaceutically acceptable carrier. In one aspect of this embodiment, the carrier comprises a biological adhesive. In one aspect of this embodiment, the carrier comprises fibrin. In one aspect of this embodiment, the administration comprises injection. In one aspect of this embodiment, the amino acid sequence of the transport agent is at the carboxy-terminal end of said polypeptide and the amino acid sequence of the active agent is at the amino terminal end of said polypeptide.
In another embodiment, this invention discloses a method of inhibiting or substantially reducing the rate of subretinal neovascularization and proliferation of neovascular tissue, preventing drusen deposition and protecting retinal photoreceptors from cell death (i.e., reducing the rate of drusen deposition and reducing the rate of retinal photoreceptor cell death) in the eye of a mammalian host comprising administration to said host a therapeutically effective amount of a pharmaceutical composition comprising: a) a polypeptide comprising an amino acid sequence of a transport agent covalently linked to an amino acid sequence of an active agent, said amino acid sequence of said active agent consisting of ADP-ribosyl transferase C3 or an amino acid sequence having at least 90% sequence identity with the amino acid sequence of SEQ ID NO: 43 and retaining ADP-ribosyl transferase activity, said amino acid sequence of said transport agent facilitating uptake of the active agent by a receptor-independent mechanism and being selected from the group consisting of SEQ ID NO: 21, SEQ ID NO: 26, SEQ ID NO: 31, SEQ ID NO: 44, SEQ ID NO: 45, SEQ ID NO: 46, SEQ ID NO: 47, and SEQ ID NO: 48, and; b) a pharmaceutically acceptable carrier. In one aspect of this embodiment, the carrier comprises a biological adhesive. In one aspect of this embodiment, the carrier comprises fibrin. In one aspect of this embodiment, the administration comprises injection. In one aspect of this embodiment, the amino acid sequence of the transport agent is at the carboxy-terminal end of said polypeptide and the amino acid sequence of the active agent is at the amino terminal end of said polypeptide.
In one aspect, a therapeutically effective amount of a polypeptide of this invention is an amount which will retard the progress of neovascularization proximal to the macula to a rate of at least 90%, preferably to a rate of at least 50%, more preferably to a rate of at least 10%, more preferably to a rate of at least 1%, and most preferably to a rate of at least 0.1% of the rate of neovascularization observed proximal to the macula in an untreated patient or in a patient treated with a control vehicle such as a carrier of a pharmaceutical composition of this invention which does not contain a polypeptide of this invention.
In another aspect, a therapeutically effective amount of a polypeptide of this invention is an amount which can retard or inhibit the rate of deposition of drusen in an eye of an average patient in a statistically relevant population of patients to produce a mean delay in the onset of vision loss that can result from said deposition, the mean delay of onset of vision loss being measured relative to the mean time of onset of vision loss that occurs in an average patient in the statistically relevant population of patients in the absence of said amount of polypeptide, the mean delay in the onset of vision loss comprising a period of at least 1 month, and more preferably a period of at least 6 months, and most preferably a period of greater than 6 months.
In another aspect, a therapeutically effective amount of a polypeptide of this invention is an amount which can retard or inhibit the progress (or rate) of photoreceptor cell death in an eye of an average patient in a statistically relevant population of patients to produce a mean delay in the onset of vision loss that can result from said cell death, the mean delay of onset of vision loss being measured relative to the mean time of onset of vision loss that occurs in an average patient in the statistically relevant population of patients in the absence of said amount of polypeptide, the mean delay in the onset of vision loss comprising a period of at least 1 month, and more preferably a period of at least 6 months, and most preferably a period of greater than 6 months.
In another aspect, a therapeutically effective amount of a polypeptide of this invention is an amount which can retard or inhibit the rate of deposition of drusen and retard or inhibit the progress (or rate) of cell death in an eye of an average patient in a statistically relevant population of patients to produce a mean delay in the onset of vision loss that can result from said deposition and said cell death, the mean delay of onset being measured relative to the mean time of onset of vision loss that occurs in an average patient in the statistically relevant population of patients in the absence of said amount of polypeptide, the mean delay in the onset of vision loss comprising a period of at least 1 month, and more preferably a period of at least 6 months, and most preferably a period of greater than 6 months.
A therapeutically effective amount or dose of a compound or composition of this invention can refer to that amount which will produce a desirable result upon administration. A therapeutically effective amount or dose can depend on a number of factors including the route of administration.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 illustrates the dose response of normal C3 with and without trituration;
FIG. 2 illustrates ADP ribosylation by C3APLT and C3APS, but not C3 after passively adding the compounds to PC-12 cells, wherein lane 1 is a negative control showing C3 alone, lane 2 is a positive control showing scrape-loaded C3, and lane 3 shows addition of C3APLT;
FIG. 3A illustrates that C3APLT penetrates cells;
FIG. 3B illustrates a lower level of cell penetration by C3 as compared to FIG. 3A ;
FIG. 4 illustrates the effectiveness of C3APLT and C3APS at low doses;
FIG. 5 illustrates the effectiveness of C3APLT and C3APS at low doses;
FIG. 6 illustrates the effectiveness of C3APLT to stimulate axon regeneration of primary neurons;
FIG. 7 illustrates the effectiveness of C3APLT to promote functional recovery after spinal cord injury;
FIG. 8 illustrates effectiveness of Tat transport sequences to enhance growth as C3-Tat (C3-TL and C3-TS) chimeras;
FIGS. 9A and 9B illustrate axon regeneration after spinal cord injury and treatment with C3APLT;
FIG. 10 illustrates effectiveness of C3APLT to prevent cell death after spinal cord injury, thereby showing that it is neuroprotective, wherein the stippled bars represent counts from spinal cord sections of rats that had a spinal cord injury and were treated with C3APLT, and the open bars show counts of cells from untreated rats with spinal cord injury;
FIG. 11 illustrates a comparison of C3APLT and C3Basic3 to promote neurite outgrowth, and;
FIG. 12 illustrates that C3APLT promotes neurite outgrowth from retinal neurons plated on inhibitory myelin or CSPG substrates. Retinal neurons plated on myelin (dark bars) or CSPG (dotted bars) substrates and treated with C3-05. FIG. 12 A illustrates the percentage of cells with neurites neurites longer than 1 cell body diameter (neurite outgrowth); FIG. 12 B illustrates the length of the longest neurite per cell (neurite length);
FIG. 13A illustrates tube formation by HUVEC endothelial cells cultured in a Matrigel™ matrix (BD Biosciences). This assay is a cell culture assay for antiogenesis. Tube formation (area 30) can be seen in the control HUVEC endothelial cell culture which does not contain a fusion protein of this invention. This tube formation can be a model for neovascularization;
FIG. 13B illustrates a substantial reduction in tube formation of HUVEC endothelial cells cultured in a Matrigel™ matrix. Cultures treated with a composition of this invention comprising a fusion protein, C3APLT as SEQ ID 43, had fewer tubes (area 31) formed in the presence of the fusion protein, thereby demonstrating an inhibition of angiogenesis by administration of the fusion protein to the cells. This substantial reduction in tube formation can be a model for a substantial reduction in neovascularization;
FIG. 14 illustrates activity of a fusion protein of the invention, C3-07, and lack of activity of an inactive mutant of the C3-07 fusion protein, C3-07Q189A, as assayed by bioassay with NG-108 cells. NG-108 cells cultured with fusion protein C3-07 exhibit accelerated neurite outgrowth (bar 42 in FIG. 14 , which shows approximately 40% neurite outgrowth). Neurite outgrowth of NG-108 cells treated with C3-07A189A (bar 41, which shows approximately 12% neurite outgrowth) is similar to that of the control (bar 40, which shows approximately 14% neurite outgrowth) of untreated cells demonstrating that protein C3-07Q189A is not active as a fusion protein to induce accelerated neurite outgrowth; and
FIG. 15 illustrates that an injection of fusion protein C3-07 can prevent death of retinal ganglion cells (RGCs) induced by crush of the optic nerve following a single injection. After axotomy (bar 51) or axotomy with injection of vehicle (bar 52), where the vehicle is phosphate buffered saline, cells die after axotomy of the optic nerve. When C3-07Q189A, an inactive mutant of fusion protein C3-07, is injected into the eye it is not able to prevent death of the RGCs (bar 53). A single injection of C3-07 prevents cell death (bar 54) and the number of surviving cells is similar to that in control (bar 50), non-axotomized retinas. The results demonstrate that C3-07 can prevent death of retinal neurons, and the neuroprotective activity of C3-07 requires that the enzymatic activity of the C3 fusion protein is retained.
DETAILED DESCRIPTION
Referring to FIG. 1 , PC-12 cells were plated on inhibitory myelin substrates (0). Unmodified C3 added to the tissue culture medium at concentration from 0.00025-50 ug/ml did not significantly improve neurite outgrowth over the untreated control (grey bars). C3 was only effective in stimulating neurite outgrowth for cells plated on myelin substrates after scrape-loading (black bars). This Figure demonstrates the limited or no penetration in cells when passively added to the tissue culture medium. Please see Example 4 below for techniques.
Referring to FIG. 2 , this Figure provides a demonstration that C3APLT and C3APS, ADP ribosylate Rho. Western blot showing RhoA in untreated cells (lane 1), and cells treated with C3APLT (lane 2) or C3APS (lane 3). When Rho is ADP ribosylated by C3 it undergoes a molecular weight shift (Lehmann et al supra), as observed for lanes 2 and 3. Please see Example 4 below for techniques.
Referring to FIG. 3 , this Figure shows intracellular activity after treatment with C3APLT. Detection that the new fusion C3 penetrates into the cells. Immunocytochemistry with anti-C3 antibody of PC-12 cells plated on myelin and treated with C3 (A) or C3APLT (13). Cells in A ( FIG. 3A ) are not immunoreactive because C3 has not penetrated into the cells. Cells in B ( FIG. 3B ) are immunoreactive and they are able to extend neurites on myelin substrates. Please see Example 4 below for techniques.
Turning to FIG. 4 , this Figure shows that C3-antennapedia fusion proteins promote growth on inhibitory substrates. The percent of neurons that grow neurites was counted for each treatment. The dose response experiment shows that C3APLT and C3APS promote more neurite growth per cell than control PC-12 cells plated on myelin (0). PC-12 cells were plated on myelin and either scrape loaded with unmodified C3 (C3 50) left untreated (0) or treated with various concentrations of C3APLT. Compared to C3 used at 25 ug/ml, C3APS is effective at stimulating more cells to grow neurites at 0.0025 ug/ml, a dose 10,000× less. Please see Example 4 below for techniques.
FIG. 5 shows a dose-response experiment showing that C3APLT and C3APS elicit long neurites to grow when cells are plated on inhibitory substrates. The length of neurites was measured for each treatment. PC-12 cells were plated on myelin and either scrape loaded with unmodified C3 (C3 50) left untreated (0) or treated with various concentrations of C3APLT. Compared to C3 used at 25 ug/ml, C3APS is effective at stimulating more cells to longer neurite growth at 0.0025 ug/ml, a dose 10,000.times. less. Please see Example 4 below for techniques.
As may be seen FIG. 6 shows primary neurons growing on inhibitory substrates after treatment with C3APLT. Rat retinal ganglion cells were plated on myelin substrates and treated with different concentrations of C3APLT. Concentrations of 0.025 and above promoted significantly longer neurites. This dose is 1000.times. lower than that of C3 needed to promote growth on myelin.
Referring to FIG. 7 , this Figure shows behavioral recovery after treatment of adult mice with C3APLT in a dose-response experiment. Mice received a dorsal hemisection of the spinal cord and were left untreated (transection), were treated with fibrin alone (fibrin) or were treated with fibrin plus C3APLT at the indicated concentrations given in ug/mouse. Each point represents one animal. The BBB score (see Example 6 for details) was assessed 24 hours after treatment. Animals treated with C3APLT exhibited a significant improvement in behavioral recovery compared to untreated animals. The effective dose of 0.5 μg is 100.times. less than unmodified C3 used (see previous experiment shown in Canadian patent application 2,325,842). Please see Example 6.
Referring to FIG. 8 , this Figure shows promotion of axon growth by C3-Tat chimeric proteins. The dose-response experiment shows that C3-TS and C3-TL promote more neurite growth per cell than control PC-12 cells plated on myelin. PC-12 cells were plated on myelin and either scrape loaded with unmodified C3 (scrape load) left untreated (myelin) or treated with various concentrations of C3-TS (grey bars) or C3-TL (black bars). Compared to C3 used at 25 ug/ml, C3-TL is effective at stimulating more cells to grow neurites at 0.0025 ug/ml, a dose 10,000.times. less than C3.
Referring to FIGS. 9A and 9B , these Figures show axon regeneration in injured spinal cord, i.e. anatomical regeneration after treatment with C3APLT. Section of the spinal cord after anterograde labeling with horseradish peroxidase conjugated to wheat germ agglutinin (WGA-HRP). A) Sprouting of cut axons into the dorsal white matter. Arrows show regenerating axons distal to the lesion. B) Same section 3 mm from the lesion site. Arrows show regenerating axons.
Referring to FIG. 10 , this Figure shows that C3-APLT protected neurons from cell death following spinal cord injury. Apoptotic (dying) cells were counted following TUNEL labeling (see Example 16) 2 mm rostral to the lesion (Rostral) at the lesion site (lesion) and 2 mm caudal to the lesion site (caudal). Bars show average counts of Tunel positive cells from 4 animals treated with fibrin only after spinal cord injury as control (white bars), or with C3APLT in fibrin at 1 μg (black bars). Treatment with C3APLT show significantly reduced numbers of Tunel-labeled cells (dying cells). Non-injured spinal cord samples were also processed and these spinal cords did not show Tunel labeling, as expected.
Referring to FIG. 11 , this Figure shows that C3APLT and C3Basic3 promote rapid neurite outgrowth compared to untreated cells when cells are plated on plastic as part of a rapid bioassay (see Example 4).
Referring to FIGS. 12A and 12B , to further support the ability of C3-like chimeric proteins to promote neurite outgrowth on inhibitory substrates, we examined the response of primary cultures plated on inhibitory substrates to C3APLT treatment. Purified retinal ganglion cells (RGCs) were plated on myelin, or CSPG substrates and treated with varying concentrations of C3APLT. During the RGC dissection great care was taken in order to try to limit the amount of mechanical manipulation of the cells, however, the isolation protocol requires that some triturating take place in order to dissociate and separate the cells. When RGCs are plated on inhibitory substrates, they maintained a similar round appearance to PC-12 cells plated on myelin. Treatment of RGCs with C3APLT promoted neurite outgrowth and increased neurite length on both myelin and CSPG substrates. In contrast to the wide range of concentrations shown to be effective in other PC-12 experiments a narrower range of C3APLT treatment, 0.025 ug/ml to 50 ug/ml promoted neurite outgrowth and increased neurite length on myelin. In the case of RGCs plated on CSPG substrates, effective concentration ranges of 0.0025 ug/ml to 50 ug/ml were observed.
Referring to FIG. 13 , a fusion protein of this invention, C3APLT, can inhibit neovascularization represented by tube formation in an in vitro model comprising HUVEC endothelial cells in culture. In the absence of the fusion protein, extensive tube formation by HUVEC endothelial cells is observed ( FIG. 13A , area 30) when the cells are cultured in a Matrigel™ matrix (BD Biosciences). This assay is a cell culture assay for antiogenesis. Tube formation in vitro can be a model for angiogenesis and neovascularization in vivo. However, in the presence of a fusion protein of this invention (e.g., C3APLT as SEQ ID 43 was administered to the cell culture in this example), a substantial reduction in the number and density of tubes formed by HUVEC endothelial cells when the cells are cultured in a Matrigel™ matrix is observed ( FIG. 13B , area 31), demonstrating an inhibition of angiogenesis by the fusion protein. Reduction in tube formation can indicate inhibition of angiogenesis. Neovascularization in retinal diseases such as macular degeneration, retinitis pigmentosa, Stargardt's Disease, diabetic retinopathy, hypertensive retinopathy, and occlusive retinopathy, can be reduced or eliminated by inhibition of angiogenesis comprising administration of a fusion protein of this invention to the eye of a patient. Administration of a fusion protein of this invention can be useful to treat such diseases.
Thus, in one aspect, this invention comprises a method of treatment of a disease of the eye selected from the group consisting of macular degeneration, retinitis pigmentosa, Stargardt's Disease, diabetic retinopathy, hypertensive retinopathy, and occlusive retinopathy, the method comprising administration to a patient in need of such treatment a therapeutically effective amount of a pharmaceutical composition comprising:
a) a polypeptide comprising an amino acid sequence of a transport agent covalently linked to an amino acid sequence of an active agent, said amino acid sequence of said active agent consisting of ADP-ribosyl transferase C3 or a fragment thereof retaining an ADP-ribosyl transferase activity, said amino acid sequence of said transport agent facilitating uptake of the active agent by a receptor-independent mechanism and being selected from the group consisting of a subdomain of HIV Tat protein, a homeodomain of antennapedia, and a Histidine tag, said polypeptide having ADP-ribosyl transferase activity, and; b) a pharmaceutically acceptable carrier.
In another aspect, this invention comprises a method of inhibiting or substantially reducing the rate of subretinal neovascularization and proliferation of neovascular tissue in the eye of a mammalian host comprising administration to said host a therapeutically effective amount of a pharmaceutical composition comprising:
a) a) a polypeptide comprising an amino acid sequence of a transport agent covalently linked to an amino acid sequence of an active agent, said amino acid sequence of said active agent consisting of ADP-ribosyl transferase C3 or a fragment thereof retaining an ADP-ribosyl transferase activity, said amino acid sequence of said transport agent facilitating uptake of the active agent by a receptor-independent mechanism and being selected from the group consisting of a subdomain of HIV Tat protein, a homeodomain of antennapedia, and a Histidine tag, said polypeptide having ADP-ribosyl transferase activity, and; b) b) a pharmaceutically acceptable carrier.
Referring to FIG. 14 , the intentional inactivity of a mutant of the C3-07 fusion protein, i.e., inactive C3-07Q189A, as assayed by a bioassay with NG-108 cells is illustrated. NG-108 cells cultured with an active fusion protein of this invention, C3-07, exhibit accelerated neurite outgrowth, which neurite outgrowth is the result of the presence of C3-07. However, neurite outgrowth of cells treated with intentionally inactive mutant C3-07A189A is similar to that of the control cells which are not treated with additional protein. The similarity to the control group demonstrates that the intentionally inactive mutant protein C3-07Q189A is inactive with respect to stimulation of neurite outgrowth.
Referring to FIG. 15 , an injection of a fusion protein of this invention, C3-07, can prevent (substantially reduce the observed rate of) death of retinal ganglion cells (RGCs) induced by crush of the optic nerve following a single injection. After axotomy or axotomy with injection of vehicle (phosphate buffered saline) cells die after axotomy of the optic nerve. When C3-07Q189A, an intentionally inactive mutant of C3-07, is injected into the eye it is not able to prevent death of the RGCs. A single injection of C3-07 prevents cell death and the number of surviving cells is similar to that in control, non-axotomized retinas. The results demonstrate that C3-07 as a fusion protein of this invention can prevent death of retinal neurons; the neuroprotective activity of C3-07 requires that the enzymatic activity of the C3 fusion protein is retained.
C3-07 exhibits ADP-ribosylation activity, whereas C3-07Q189A is intentionally inactive with respect to ADP-ribosylation activity.
Administration of a pharmaceutical composition comprising a fusion protein of this invention to a patient in need of treatment for a disease of the eye selected from the group consisting of macular degeneration, retinitis pigmentosa, Stargardt's Disease, diabetic retinopathy, hypertensive retinopathy, and occlusive retinopathy can substantially reduce or prevent angiogenesis associated with subretinal neovascularization, choroid neovascularization underlying the macula, and a proliferation of neovascular tissue in the subretinal choroid proximal to the macula in an eye in a mammalian host and comprises a method of treatment of a disease of the eye selected from the group consisting of macular degeneration, retinitis pigmentosa, Stargardt's Disease, diabetic retinopathy, hypertensive retinopathy, and occlusive retinopathy. In one aspect, the compositions of this invention are useful for inhibiting or substantially reducing the rate of subretinal neovascularization and proliferation of neovascular tissue related to a disease of the eye selected from the group consisting of macular degeneration, retinitis pigmentosa, Stargardt's Disease, diabetic retinopathy, hypertensive retinopathy, and occlusive retinopathy. The method can be useful as a prophylactic treatment to prevent further onset or progression of macular degeneration in an eye that exhibits symptoms of a disease of the eye selected from the group consisting of macular degeneration, retinitis pigmentosa, Stargardt's Disease, diabetic retinopathy, hypertensive retinopathy, and occlusive retinopathy. In another aspect, the method can be useful as a prophylactic treatment to prevent the deposition of drusen and the death of cells in the macula. In another aspect, the method can prevent the death of photoreceptor cells (which photoreceptor cells are also herein referred to as photoreceptors) in the eye of a patient by acting on intracellular mechanisms of the regulation of cell death. The method can also be useful to prevent onset or progression of macular degeneration in an eye that does not exhibit vision-obscuring symptoms of macular degeneration, especially in an eye of a patient whose other eye does exhibit vision-obscuring symptoms of macular degeneration.
In another aspect of this invention, a method of treatment of a disease of the eye selected from the group consisting of macular degeneration, retinitis pigmentosa, Stargardt's Disease, diabetic retinopathy, hypertensive retinopathy, and occlusive retinopathy comprises administration such as by injection or implantation into tissue proximal to the eye of a therapeutically effective amount of a polypeptide of this invention, or of a sterile pharmaceutical composition of this invention suitable for injectable administration and comprising a polypeptide of this invention and a carrier suitable for injectable use (e.g., sterile, sterilizable, and isotonic with blood), which polypeptide or pharmaceutical composition can prevent or delay the onset of angiogenesis associated with the group consisting of subretinal neovascularization, choroid neovascularization underlying the macula, and a proliferation of neovascular tissue in the subretinal choroid proximal to the macula in an eye of an average patient in a statistically relevant population of patients to produce a mean delay in the onset of vision loss that can result from said angiogenesis, the mean delay of onset being measured relative to the mean time of onset of vision loss that occurs in an average patient in the statistically relevant population of patients in the absence of said amount of polypeptide, the mean delay in the onset of vision loss comprising a period of at least 1 month, and more preferably a period of at least 6 months, and most preferably a period of greater than 6 months.
Inhibition of angiogenesis by a pharmaceutical composition comprising a fusion protein of this invention such as C3APLT can be evaluated in an in vitro system that can also be useful for the study of angiogenesis in the growth of a tumor, i.e., a system comprising cultivation of endothelial cells in the presence of an extract of basement membrane (Matrigel™) as a model for angiogenesis and for neovascularization and proliferation of neovascular tissue in the eye of a mammal. In the experimental observation conditions, capillary-like structures or tubules associated with angiogenesis or blood vessel capillary formation can be viewed under a microscope. The inhibitory effect of a fusion protein of this invention such as C3APLT on the progress of angiogenesis or on the formation of a tubular capillary network or on the disruption of the process or progress of tumor-associated angiogenesis can be observed by following the disappearance of tubular structures in a Matrigel assay.
Matrigel™ Matrix (BD Biosciences) is a solubulized basement membrane preparation extracted from EHS mouse sarcoma, a tumor rich in ECM proteins. Its major components are laminin, collagen IV, heparan sulfate proteoglycans, and entactin. At room temperature, BD Matrigel™ Matrix polymerizes to produce biologically active matrix material which can mimic mammalian cellular basement membrane, wherein cells can behave in vitro in a manner similar to in vivo conditions. Matrigel™ Matrix can provide a physiologically relevant environment for studies of cell morphology, biochemical function, migration or invasion, and gene expression.
In a Matrigel assay, Matrigel (about 12.5 mg/mL) is thawed at about 4° C. The matrix (about 50 microliters (uL)) is added to each well of a 96 well plate and allowed to solidify for about 10 min at about 37° C. The wells containing solid Matrigel are incubated for about 30 minutes with human umbilical vein endothelial cells (HUVEC cells) at a concentration of about 15,000 cells per well. When the cells are adhered, medium is removed and replaced by fresh medium supplemented with a fusion protein of this invention such as C3APLT and incubated at 37° C. for about 6 to about 8 hours. Control wells are incubated with medium alone. To analyze the growth, tube formation can be visualized by microscopy at, for example, about 50× magnification. The relative mean length, Yx, of an angiogenesis-derived capillary network observed in an evaluation of a pharmaceutical composition comprising a fusion protein, x, of this invention can be quantified using Northern Eclipse software according to the instructions.
Data from a typical Matrigel assay experiment, for example relating to the effect of a pharmaceutical composition comprising a fusion protein designated as C3APLT on length of an angiogenesis-derived capillary network are summarized in Table 3. These data show that the network formation was inhibited by approximately 13% to about 20% under the dose and formulation conditions used versus the inhibition produced by a control vehicle wherein zero inhibition provides 100% growth. This effect on angiogenesis can be enhanced by using higher doses of fusion protein and by preincubation of the HUVEC cells with fusion protein C3APLT prior to addition of the cells to Matrigel. The anti-angiogenesis effect of a composition comprising a polypeptide of this invention comprising an amino acid sequence of a transport agent covalently linked to an amino acid sequence of an active agent, wherein the amino acid sequence of the active agent retains an ADP-ribosyl transferase activity can be useful for inhibiting or substantially reducing the rate of subretinal neovascularization and proliferation of neovascular tissue in the eye of a mammalian host when the composition is administered to the mammal according to the methods of this invention.
TABLE 3
Anti-angiogenesis effect of a pharmaceutical composition comprising
a fusion protein, C3APLT, on the mean length of a capillary network
in a Matrigel matrix assay
Relative mean length of
a capillary network
produced in the presence
of a pharmaceutical
Mean length
composition comprising
of a
Relative mean length of a
a fusion protein,
capillary network
capillary network produced
C3APLT, at a
associated with
in the presence of a vehicle
concentration of 10
angiogenesis
control
micrograms per milliter
Y1
100
86.4
Y2
100
78.2
Y3
100
86.7
It is an advantage that the current invention provides compositions comprising a fusion protein of this invention, which fusion protein after administration to a mammal, preferably proximal to the eye or into a blood vessel that provides blood to the eye, has the ability to penetrate endothelial cells in the eye that in the absence of the fusion protein can form new blood vessels. Thus, when administered to the eye of a mammal, the compositions of this invention can inhibit or substantially reduce the rate of subretinal neovascularization and proliferation of neovascular tissue in the eye of the mammal.
Description of how to Measure Effect on Cell Death In Vivo
One system to examine the neuroprotective effect of fusion proteins in the eye is a model of optic nerve axotomy. In the visual system, retinal ganglion cells die after optic nerve injury, and the severity and rate of cell death depends on the proximity of axonal injury to the eye. In rats, transection of the optic nerve close to the eye causes a delayed RGC death, with cells beginning to die approximately 4 days after axotomy. It has been well demonstrated that intervention with factors that prevent cell death give partial and transient rescue of cells. Intraocular injection of growth factors that include BDNF, NT4, GDNF, CNTF and FGF can rescue RGCs from axotomy-induced cell death. Other ways to rescue cells are to interfere with enzymes that contribute to apoptotic cell death. Lens injury that induces macrophage activation and injection of zymosan from yeast cell walls promote survival of RGCs. To study the inactivation of Rho on RGC survival C3-07 was injected into the vitreous after axotomy: To separate effects of C3-07 on Rho activation from possible inflammatory responses induced by the intravitreal injection of a protein, we used an intentionally inactive mutant of C3-07 protein, i.e., C3-07Q189A, that lacks ADP-ribosylation activity but maintains normal glycohydrolysis activity. To our knowledge, this is the first in vivo study using a mutant C3 exoenzyme or C3-fusion proteins to study cell survival in the retina. We found that a single injection of C3-APLT or C3-07 promoted survival of RGCs equivalent to rates reported for BDNF, and that the effect of C3-07 is dependant on its ability to inactivate Rho.
Other animal models can be used to assess damage to and rescue of photoreceptor cells (e.g., reduction in the rate of death of photoreceptor cells). Useful are genetic models of retinal degeneration and other diseases of the eye in mice. The rescue of photoreceptors can be demonstrated in RCS rats that have an inherited retinal degeneration, or in transgenic lines of mice that express mutated forms of rhodopsin that cause retinitis pigmentosa in human. Such mice are commercially available from Jackson labs. Retinal detachment also leads to death of photoreceptor cells, and this provides another animal model to demonstrate neuroprotection (e.g., reduction in the rate of death of photoreceptor cells). To assess the effect of compounds on neovascularization that occurs in wet macular degeneration and related diseases, animal models are also used. Useful to model neovascularization of the retina are rodent models of oxygen-induced retinopathy of the neuroborn rodents, sometimes referred to as retinopathy of prematurity (ROP).
Method for Making the C3APL, C3APLT, and C3APS
C3APL is the name given to the protein made by ligating a cDNA encoding C3 (Dillon and Feig (1995) 256: 174-184) with cDNA encoding the antennapedia homeodomain (Bloch-Gallego (1993) 120: 485-492). The stop codon at the 3′ end of the DNA was replaced with an EcoR I site by polymerase chain reaction (PCR) using the primers (oligonucleotides) 5′GAA TTC TTT AGG ATT GAT AGC TGT GCC 3′ (SEQ ID NO: 1) and 5′GGT GGC GAC CAT CCT CCA AAA 3′ (SEQ ID NO: 2). The PCR product was sub-cloned into a pSTBlue-1 vector (Novagen, city), then cloned into a pGEX-4T vector using BamH I and Not I restriction site. This vector was called pGEX-4T/C3. The antennapedia sequence used to add to the 3′ end of C3 in pGEX-4T/C3 was created by PCR from the pET-3a vector (Bloch-Gallego (1993) 120: 485-492, Derossi (1994) 269: 10444-10450), subcloned into a pSTBlue-1 blunt vector, then cloned into the pGEX-4T/C3, using the restriction sites EcoR I and Sal I, creating pGEX-4T/C3APL. Another clone (C3APLT) with a frameshift mutation was selected, and the protein made and tested. When the cultures tested positive despite the mutation, the clone was resequenced by another company to confirm the mutation, and this clone was called C3APLT. To confirm the sequence of C3APLT, the coding sequence from both strands was sequenced. The sequence for this clone is given in Examples 16 and 17 (nucleotide sequence of C3APLT; SEQ ID NO: 42, amino acid sequence of C3APLT; SEQ ID NO: 43).
A shorter version of the Antennapedia (pGEX-4T/C3APS) was also made. This chimeric sequence was made by ligating oligonucleotides encoding the short antennapedia peptide (Maizel (1999) 126: 3183-3190) into the pGEX-4T/C3 vector cut with EcoR I and Sal I. The recombinant C3APLT and C3APS cDNAs were separately transformed into bacteria, and after the recombinant proteins were produced, a bacterial homogenate was obtained by sonication, and the homogenate cleared by centrifugation. Glutathione-agarose beads (Sigma) were added to the cleared lysate and placed on a rotating plate for 2-3 hours, then washed extensively. To remove the glutathione S transferase sequence from the recombinant protein, 20 U (unit) of Thrombin was added, the beads were left on a rotator overnight at 4° C. After cleavage with thrombin, the beads were loaded into an empty 20 ml column, and the proteins eluted with PBS (phosphate buffered saline). Aliquots containing recombinant protein were pooled and 100 μl p-aminobenzamidine agarose beads (Sigma) were added and left mixing for 45 minutes at 4° C. to remove thrombin, then recombinant protein was isolated from the beads by centrifugation. Purity of the sample was determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), and bioactivity bioassay with PC-12 cells was performed (See Lehmann et al supra).
Other possible methods for making bioactive chimeric proteins include anion exchange chromatography. For this, the GST tag is not required and can be removed. The cDNA can then be cloned into a high expression bacterial vector, such as pET, as given in Example 16.
The Rho antagonist is a recombinant protein and can be made according to methods present in the art. The proteins of the present invention may be prepared from bacterial cell extracts, or through the use of recombinant techniques by transformation, transfection, or infection of a host cell with all or part of a C3-encoding DNA fragment with an antennapedia-derived transport sequence in a suitable expression vehicle. Those skilled in the field of molecular biology will understand that any of a wide variety of expression systems can be used to provide the recombinant protein. The precise host cell used is not critical to the invention.
Any fusion protein can be readily purified by utilizing either affinity purification techniques or more traditional column chromatography. Affinity techniques include, but are not restricted to GST (gluathionie-S-transferase), or the use of an antibody specific for the fusion protein being expressed, or the use of a histidine tag. Alternatively, recombinant protein can be fused to an immunoglobulin Fc domain. Such a fusion protein can be readily purified using a protein A column. It is envisioned that small molecule mimetics of the above-described antagonists are also encompassed by the invention.
Testing the Bioactivity of C3APLT, C3APS, C3-TL and C3-TS
To test the efficacy of C3APLT, C3APS, C3-TL and C3-TS a number of experiments were performed with PC-12 cells, a neural cell line, grown on growth inhibitory substrates (see Lehmann et al supra). PC-12 cells were plated on myelin substrates as described (Lehmann et al, supra). C3, C3APLT, C3APS, C3-TL or C3-TS were added at different concentrations without trituration (please refer to FIGS. 4 , 5 and 8 for concentrations used). C3 added passively to the culture medium in this way was not able to promote neurite growth in the growth inhibitory substrates because cells must be triturated for C3 to enter the cells and be active ( FIG. 1 ). Both C3APLT and C3APS were able to ADP ribosylate Rho to cause a shift in the molecular weight of RhoA ( FIG. 2 ). Both C3APLT and C3APS were able to promote neurite growth and enter neurons after being added passively to the culture medium ( FIG. 3 , FIGS. 4 and 5 ). Dose-response experiment where concentrations of 0.25 ng/ml, 2.5 ng/ml, 25 ng/ml, 250 ng/ml and 2.5 μg/ml (2.5 microgram/milliliter) and 25 μg/ml (25 microgram/milliliter) were tested and showed that C3APLT and C3APS helped more neurons differentiate neurites at doses 10,000 fold less than C3 ( FIG. 4 ). Dose response experiments where concentrations of 0.25 ng/ml, 2.5 ng/ml, 25 ng/ml, 250 ng/ml and 2.5 μg/ml (2.5 microgram/milliliter) and 25 μg/ml (25 microgram/milliliter) were tested and showed that C3APLT was able to promote long neurite growth when added at a minimum concentration of 0.0025 ug/ml (0.0025 microgram/milliliter) ( FIG. 5 ). These concentrations of 2.5 ng/ml and 25 ng/ml for C3APLT and C3APS, represent 10,000 and 1,000 times less than the dose needed with C3, respectively. Moreover, at the highest concentration tested, 50 ug/ml (50 microgram/milliliter), these two new Rho antagonists did not exhibit toxic effects on PC-12 cells, and were able to stimulate neurite outgrowth on growth inhibitory substrates.
C3-TL and C3-TS also were tested at concentrations of 0.25 ng/ml, 2.5 ng/ml, 25 ng/ml, 250 ng/ml and 2.5 μg/ml (2.5 microgram/milliliter) and 25 μg/ml (25 microgram/milliliter) and were found to be able to promote neurite growth on myelin substrates at doses significantly less than C3 ( FIG. 8 ). C3Basic3 was tested at 50 ug/ml in a fast growth assay ( FIG. 11 ).
To verify the ability of C3APLT and C3APS to promote growth from primary neurons, primary retinal cultures were prepared, and the neurons were plated on myelin substrates as described with respect to Example 5. In the absence of treatment with C3APLT or C3APS, the cells remained round and were not able to grow neurites. When treated with C3APLT or C3APS, retinal neurons were able to extend long neurites on inhibitory myelin substrates ( FIG. 6 ).
Next, was tested the ability of C3APLT and C3APS to promote growth on a different type of growth inhibitory substrate relevant to the type of growth inhibitory proteins found at glial scars. Chamber slides were coated with a mixture of chondroitin sulfate proteoglycans (Chemicon), and then plated with retinal neurons (results presented in FIG. 12 ). The neurons were not able to extend neurites on the proteoglycan substrates, but when treated with C3APLT or C3APS, they extended long neurites. These studies demonstrate that C3APLT and C3APS can be used to promote neurite growth on myelin and on proteoglycans, the major classes of inhibitory substrates that prevent repair after injury in the CNS.
Testing Ability of C3APLT to Promote Regeneration and Functional Recovery after Spinal Cord Injury
To test if C3APLT could promote repair after spinal cord injury, fully adult mice were used (as described with respect to Example 6). A dorsal hemisection was made at T8 (thoracic spinal level 8), and mice were treated with different amounts ( FIG. 7 ) of C3APLT in a fibrin glue as described (McKerracher, US patent pending (delivery patent)). In previous known experiments with C3, it was found that 40-50 μg was needed to promote anatomical regeneration in optic nerve (Lehmann et all supra). We tested different doses (see FIG. 7 ) of C3APLT ranging from 1 μg (1 microgram/milliliter) to 50 μg (50 microgram/milliliter) and assessed animals for behavioral recovery according the BBB scale (Basso (1995) 12: 1-21).
The day following surgery and application of C3APLT, behavioral testing began. The animals were placed in an open field environment that consisted of a rubber mat approximately 4′ by 3′ in size. The animals were left to move randomly, the movement of the animals were videotaped. For each test two observers scored the animals for ability to move ankle, knee and hip joints in the early phase of recovery. Previously C3 treatment of mice was seen to lead to functional recovery observable 24 hours after treatment. In mice treated with C3APLT, functional recovery could be observed as early as 24 hours after spinal cord injury ( FIG. 7 ). Untreated mice exhibit a function recovery score according to the BBB scale averaging 0, whereas mice treated with C3 are able to walk and have a BBB score averaging 8 ( FIG. 7 ). At higher concentrations of 50 ug, about 50% of the mice treated with C3APLT died within 24 hours. However, of the mice that survived, they exhibited good long-term functional recovery. These results demonstrate that C3APLT effectively promotes functional recovery early after spinal cord injury, and that it is effective at much lower doses than C3. However, at high concentrations, C3APLT appears to exhibit toxicity, and therefore careful doing will be required for clinical use.
Qualitative observations of the videotapes showed that only animals that received C3APLT reached the late phase of recovery after 30 days of treatment. Untreated control animals did not typically pass beyond the early phase of recovery. These results indicate that the application of C3APLT improved long-term functional recovery after spinal cord injury compared to no treatment, injury alone, or fibrin adhesive alone.
To test if the early recovery was due to neuroprotection, spinal cord sections were examined for apoptosis by Tunel labeling following manufacturer's instruction (Roche Diagnostic). C3APLT was able to reduce the number of dying cells observed at the lesion site. Therefore, C3APLT should be an effective neuroprotective agent for treatment of ischemia, such as follows stroke.
EXAMPLE 1
DNA and Protein Sequence Details of C3APL
Nucleotide Sequence of C3APL
It has been reported that the long version of antennapedia transport sequence can enhance neurite growth (Bloch-Gallego, E., LeRoux, I.-, Joliot, A. H., Volovitch, M., Henderson, C. E., Prochiantz, A. 1993. J. Cell Biol. 120:485). Therefore, this sequence is expected to enhance neurite growth. For the sequence given below, the start site, is in the GST sequence of the plasmid (not shown). The vector with the GST sequence is commercially available and thus the entire GST sequence including the start was not sequenced. It was desired to determine only the sequence located 3′ to the thrombin cleavage site which releases C3 conjugate from the GST sequence. The GST sequence is cleaved with thrombin.
The APL transport sequence (SEQ ID NO.: 44) is as follows:
Val Met Glu Ser Arg Lys Arg Ala Arg Gln Thr Tyr
1 5 10
Thr Arg Tyr Gln Thr Leu Glu Leu Glu Lys Glu Phe
15 20
His Phe Asn Arg Tyr Leu Thr Arg Arg Arg Arg Ile
25 30 35
Glu Ile Ala His Ala Leu Cys Leu Thr Glu Arg Gln
40 45
Ile Lys Ile Trp Phe Gln Asn Arg Arg Met Lys Trp
50 55 60
Lys Lys Glu Asn
Nucleotide Sequence of C3APL (SEQ ID NO: 3)
ggatcctcta gagtcgacct gcaggcatgc aatgcttatt ccattaatca aaaggcttat
60
tcaaatactt accaggagtt tactaatatt gatcaagcaa aagcttgggg taatgctcag
120
tataaaaagt atggactaag caaatcagaa aaagaagcta tagtatcata tactaaaagc
180
gctagtgaaa taaatggaaa gctaagacaa aataagggag ttatcaatgg atttccttca
240
aatttaataa aacaagttga acttttagat aaatctttta ataaaatgaa gacccctgaa
300
aatattatgt tatttagagg cgacgaccct gcttatttag gaacagaatt tcaaaacact
360
cttcttaatt caaatggtac aattaataaa acggcttttg aaaaggctaa agctaagttt
420
ttaaataaag atagacttga atatggatat attagtactt cattaatgaa tgtctctcaa
480
tttgcaggaa gaccaattat tacacaattt aaagtagcaa aaggctcaaa ggcaggatat
540
attgacccta ttagtgcttt tcagggacaa cttgaaatgt tgcttcctag acatagtact
600
tatcatatag acgatatgag attgtcttct gatggtaaac aaataataat tacagcaaca
660
atgatgggca cagctatcaa tcctaaagaa ttcgtgatgg aatcccgcaa acgcgcaagg
720
cagacataca cccggtacca gactctagag ctagagaagg agtttcactt caatcgctac
780
ttgacccgtc ggcgaaggat cgagatcgcc cacgccctgt gcctcacgga gcgccagata
840
aagatttggt tccagaatcg gcgcatgaag tggaagaagg agaactga
888
Amino Acid Sequence of C3APL (SEQ ID NO: 4)
Gly Ser Ser Arg Val Asp Leu Gln Ala Cys Asn Ala Tyr Ser Ile Asn
1 5 10 15
Gln Lys Ala Tyr Ser Asn Thr Tyr Gln Glu Phe Thr Asn Ile Asp Gln
20 25 30
Ala Lys Ala Trp Gly Asn Ala Gln Tyr Lys Lys Tyr Gly Leu Ser Lys
35 40 45
Ser Glu Lys Glu Ala Ile Val Ser Tyr Thr Lys Ser Ala Ser Glu Ile
50 55 60
Asn Gly Lys Leu Arg Gln Asn Lys Gly Val Ile Asn Gly Phe Pro Ser
65 70 75 80
Asn Leu Ile Lys Gln Val Glu Leu Leu Asp Lys Ser Phe Asn Lys Met
85 90 95
Lys Thr Pro Glu Asn Ile Met Leu Phe Arg Gly Asp Asp Pro Ala Tyr
100 105 110
Leu Gly Thr Glu Phe Gln Asn Thr Leu Leu Asn Ser Asn Gly Thr Ile
115 120 125
Asn Lys Thr Ala Phe Glu Lys Ala Lys Ala Lys Phe Leu Asn Lys Asp
130 135 140
Arg Leu Glu Tyr Gly Tyr Ile Ser Thr Ser Leu Met Asn Val Ser Gln
145 150 155 160
Phe Ala Gly Arg Pro Ile Ile Thr Gln Phe Lys Val Ala Lys Gly Ser
165 170 175
Lys Ala Gly Tyr Ile Asp Pro Ile Ser Ala Phe Gln Gly Gln Leu Glu
180 185 190
Met Leu Leu Pro Arg His Ser Thr Tyr His Ile Asp Asp Met Arg Leu
195 200 205
Ser Ser Asp Gly Lys Gln Ile Ile Ile Thr Ala Thr Met Met Gly Thr
210 215 220
Ala Ile Asn Pro Lys Glu Phe Val Met Glu Ser Arg Lys Arg Ala Arg
225 230 235 240
Gln Thr Tyr Thr Arg Tyr Gln Thr Leu Glu Leu Glu Lys Glu Phe His
245 250 255
Phe Asn Arg Tyr Leu Thr Arg Arg Arg Arg Ile Glu Ile Ala His Ala
260 265 270
Leu Cys Leu Thr Glu Arg Gln Ile Lys Ile Trp Phe Gln Asn Arg Arg
275 280 285
Met Lys Trp Lys Lys Glu Asn
290 295
Physical Characteristics of C3APL
Molecular Weight 34098.03 Daltons 295 Amino Acids 48 Strongly Basic(+) Amino Acids (K,R) 28 Strongly Acidic(−) Amino Acids (D,E) 89 Hydrophobic Amino Acids (A, I, L, F, W, V) 94 Polar Amino Acids (N, C, Q, S, T, Y) 9.847 Isolectric Point 20.524 Charge at PH 7.0 Davis, Botstein, Roth Melting Temp C. 79.48
EXAMPLE 2
DNA and Protein Sequence Details of C3APS
Nucleotide sequence of C3APS (SEQ ID NO: 5). The start site, is in the GST sequence of the plasmid, not shown here.
ggatcctcta gagtcgacct gcaggcatgc aatgcttatt ccattaatca aaaggcttat
60
tcaaatactt accaggagtt tactaatatt gatcaagcaa aagcttgggg taatgctcag
120
tataaaaagt atggactaag caaatcagaa aaagaagcta tagtatcata tactaaaagc
180
gctagtgaaa taaatggaaa gctaagacaa aataagggag ttatcaatgg atttccttca
240
aatttaataa aacaagttga acttttagat aaatctttta ataaaatgaa gacccctgaa
300
aatattatgt tatttagagg cgacgaccct gcttatttag gaacagaatt tcaaaacact
360
cttcttaatt caaatggtac aattaataaa acggcttttg aaaaggctaa agctaagttt
420
ttaaataaag atagacttga atatggatat attagtactt cattaatgaa tgtctctcaa
480
tttgcaggaa gaccaattat tacacaattt aaagtagcaa aaggctcaaa ggcaggatat
540
attgacccta ttagtgcttt tcagggacaa cttgaaatgt tgcttcctag acatagtact
600
tatcatatag acgatatgag attgtcttct gatggtaaac aaataataat tacagcaaca
660
atgatgggca cagctatcaa tcctaaagaa ttccgccaga tcaagatttg gttccagaat
720
cgtcgcatga agtggaagaa ggtcgactcg agcggccgca tcgtgactga ctga
774
The APS transport sequence (SEQ ID NO.: 45) is as follows:
Arg Gln Ile Lys Ile Trp Phe Gln Asn Arg Arg Met
1 5 10
Lys Trp Lys Lys Val Asp Ser
15
Amino Acid Sequence for C3APS (SEQ ID NO: 6)
Gly Ser Ser Arg Val Asp Leu Gln Ala Cys Asn Ala Tyr Ser Ile Asn
1 5 10 15
Gln Lys Ala Tyr Ser Asn Thr Tyr Gln Glu Phe Thr Asn Ile Asp Gln
20 25 30
Ala Lys Ala Trp Gly Asn Ala Gln Tyr Lys Lys Tyr Gly Leu Ser Lys
35 40 45
Ser Glu Lys Glu Ala Ile Val Ser Tyr Thr Lys Ser Ala Ser Glu Ile
50 55 60
Asn Gly Lys Leu Arg Gln Asn Lys Gly Val Ile Asn Gly Phe Pro Ser
65 70 75 80
Asn Leu Ile Lys Gln Val Glu Leu Leu Asp Lys Ser Phe Asn Lys Met
85 90 95
Lys Thr Pro Glu Asn Ile Met Leu Phe Arg Gly Asp Asp Pro Ala Tyr
100 105 110
Leu Gly Thr Glu Phe Gln Asn Thr Leu Leu Asn Ser Asn Gly Thr Ile
115 120 125
Asn Lys Thr Ala Phe Glu Lys Ala Lys Ala Lys Phe Leu Asn Lys Asp
130 135 140
Arg Leu Glu Tyr Gly Tyr Ile Ser Thr Ser Leu Met Asn Val Ser Gln
145 150 155 160
Phe Ala Gly Arg Pro Ile Ile Thr Gln Phe Lys Val Ala Lys Gly Ser
165 170 175
Lys Ala Gly Tyr Ile Asp Pro Ile Ser Ala Phe Gln Gly Gln Leu Glu
180 185 190
Met Leu Leu Pro Arg His Ser Thr Tyr His Ile Asp Asp Met Arg Leu
195 200 205
Ser Ser Asp Gly Lys Gln Ile Ile Ile Thr Ala Thr Met Met Gly Thr
210 215 220
Ala Ile Asn Pro Lys Glu Phe Arg Gln Ile Lys Ile Trp Phe Gln Asn
225 230 235 240
Arg Arg Met Lys Trp Lys Lys Val Asp Ser Ser Gly Arg Ile Val Thr
245 250 255
Asp
Physical Characteristics of C3APS
Molecular Weight 29088.22 Daltons 257 Amino Acids 38 Strongly Basic(+) Amino Acids (K,R) 23 Strongly Acidic(−) Amino Acids (D,E) 79 Hydrophobic Amino Acids (A, I, L, F, W, V) 83 Polar Amino Acids (N, C, Q, S, T, Y) 9.745 Isolectric Point 15.211 Charge at PH 7.0 Davis, Botstein, Roth Melting Temp C. 78.34
EXAMPLE 3
Method for Making the C3APLT and C3APS Proteins
C3APL (amino acid sequence: SEQ ID NO.: 4) and C3APLT (amino acid sequence; SEQ ID NO: 37) are the names given to the proteins encoded by cDNAs made by ligating the functional domain of C3 transferase and the homeobox region of the transcription factor called antennapedia (Bloch-Gallego (1993) 120: 485-492) in the following way. A cDNA encoding C3 (Dillon and Feig (1995) 256: 174-184) cloned in the plasmid vector pGEX-2T was used for the C3 portion of the chimeric protein. The stop codon at the 3′ end of the DNA was replaced with an EcoR I site by polymerase chain reaction using the primers 5′GAA TTC TTT AGG ATT GAT AGC TGT GCC 3′ (SEQ ID NO: 1) and 5′GGT GGC GAC CAT CCT CCA AAA 3′ (SEQ ID NO: 2). The PCR product was sub-cloned into a pSTBlue-1 vector (Novagen, city), then cloned into a pGEX-4T vector using BamH I and Not I restriction site. This vector was called pGEX-4T/C3. The pGEX-4T vector has a 5′ glutathione S transferase (GST) sequence for use in affinity purification. The antennapedia sequence used to add to the 3′ end of C3 in pGEX-4T/C3 was created by PCR from the pET-3a vector (Bloch-Gallego (1993) 120: 485-492, Derossi (1994) 269: 10444-10450). The primers used were 5′GAA TCC CGC AAA CGC GCA AGG CAG 3′ (SEQ ID NO: 7) and 5′TCA GTT CTC CTT CTT CCA CTT CAT GCG 3′ (SEQ ID NO: 8). The PCR product obtained from the reaction was subcloned into a pSTBlue-1 blunt vector, then cloned into the pGEX-4T/C3, using the restriction sites EcoR I and Sal I, creating pGEX-4T/C3APL and C3APLT. C3APLT was selected for the presence of a frameshift mutation giving a transport region moiety rich in prolines.
A shorter version of the antennapedia (pGEX-4T/C3AP-short) (amino acid sequence of C3APS; SEQ ID NO.: 6) was also made. This chimeric sequence was made by ligating oligonucleotides encoding the short antennapedia peptide (Maizel (1999) 126: 3183-3190) into the pGEX-4T/C3 vector cut with EcoR I and Sal I. For pGEX-4T/C3AP-short the sequences of the oligos made were 5′AAT TCC GCC AGA TCA AGA TTT GGT TCC AGA ATC GTC GCA TGA AGT GGA AGA AGG 3′ (SEQ ID NO: 9) and 5′GGC GGT CTA GTT CTA AAC CAA GCT CTT AGC AGC GTA GTT CAC CTT CTT CCA GCT 3′ (SEQ ID NO: 10). The two strands were annealed together by mixing equal amounts of the oligonucleotides, heating at 72° C. for 5 minutes and then leaving them at room temperature for 15 minutes. The oligonucleotides were ligated into the pGEX4T/C3 vector and clones were picked and analyzed.
To prepare recombinant C3APLT (SEQ ID NO.: 37) and C3APS (SEQ ID NO.: 6) proteins, the plasmids containing the corresponding cDNAs (pGEX-4T/C3APLT and pGEX-4T/C3AP-short) were transformed into bacteria, strain XL-1 blue competent E. coli . The bacteria were grown in L-broth (10 g/L Bacto-Tryptone, 5 g/L Yeast Extract, 10 g/L NaCl) with ampicillin at 50 ug/ml (BMC-Roche), in a shaking incubator for 1 hr at 37° C. and 300 rpm. Isopropyl .beta.-D-thiogalactopyranoside (IPTG), (Gibco) was added to a final concentration of 0.5 mM to induce the production of recombinant protein and the culture was grown for a further 6 hours at 37° C. and 250 rpm. Bacteria pellets were obtained by centrifugation in 250 ml centrifuge bottles at 7000 rpm for 6 minutes at 4° C. Each pellet was re-suspended in 10 ml of Buffer A (50 mM Tris, pH 7.5, 50 mM NaCl, 5 mM MgCl2, 1 mM DTT) plus 1 mM PMSF. All re-suspended pellets were pooled and transferred to a 100 ml plastic beaker on ice. The remaining Buffer A with PMSF was added to the pooled sample. The bacteria sample was sonicated 6.times.20 seconds using a Branson Sonifier 450 probe sonicator. Both the bacteria and probe were cooled on ice 1 minute between sonications. The sonicate was centrifuged in a Sorvall SS-34 rotor at 16,000 rpm for 12 minutes at 4° C. to clarify the supernatant. The supernatant was transferred into fresh SS-34 tubes and re-spun at 12,000 rpm for 12 minutes at 4° C. Up to 20 ml of Glutathione-agarose beads (Sigma) were added to the cleared lysate and placed on a rotating plate for 2-3 hours. The beads were washed 4 times with buffer B, (Buffer A, NaCl is 150 mM, no PSMF) then 2 times with Buffer C (Buffer B+2.5 mM CaCl2). The final wash was poured out till the beads created a thick slurry. To remove the glutathione S transferase sequence from the recombinant protein, 20 U of Thrombin (Bovine, Plasminogen-free, Calbiochem) was added, the beads were left on a rotator overnight at 4° C. After cleavage with thrombin the beads were loaded into an empty 20 ml column. Approximately 20 aliquots of 1 ml were collected by elution with PBS. Samples of each aliquot of 0.5 ul were spotted on nitrocellulose and stained with Amido Black to determine the protein peak. Aliquots containing fusion proteins were pooled and 100 □1 (100 microliter) p-aminobenzamidine agarose beads (Sigma) were added and left mixing for 45 minutes at 4° C. This last step removed the thrombin from the recombinant protein sample. The recombinant protein was centrifuged to remove the beads and then concentrated using a centriprep-10 concentrator (Amicon). The concentrated recombinant protein was desalted with a PD-10 column (Pharmacia, containing Sephadex G-25M) and ten 0.5 ml aliquots were collected. A dot-blot was done on these samples to determine the protein peak, and the appropriate aliquots pooled, filter-sterilized, and stored at −80° C. A protein assay (DC assay, Biorad) was used to determine the concentration of recombinant protein. Purity of the sample was determined by SDS-PAGE, and bioactivity bioassay with PC-12 cells.
EXAMPLE 4
Testing of Efficacy of C3APLT and C3APS in Tissue Culture
To test the ability of C3APLT and C3APS to overcome growth inhibition, PC-12 cells were plated on myelin, a growth inhibitory substrate. The myelin was purified from bovine brain (Norton and Poduslo (1973) 21: 749-757). In some other experiments chondroitin sulfate proteoglycan (CSPG) substrates were made from a purchased protein composition (Chemicon). Before coating coverslips or wells of a 96 well plate, they were coated with poly-L-lysine (0.025 □g/ml; 0.025 microgram/milliliter) (Sigma, St. Louis, Mo.), washed with water and allowed to dry. Myelin stored as a 1 mg/ml solution at −80° C. was thawed at 37° C., and vortexed. The myelin was plated at 8 ug/well in a 8 well chamber Lab-Tek slides (Nuc, Naperville, Ill.). The myelin solution was left to dry overnight in a sterile tissue culture hood. The next morning the substrate was washed gently with phosphate buffered saline, and then cells in media were added to the substrate. PC-12 cells (Lehmann et al., 1999) were grown in DMEM with 10% horse serum (HS) and 5% fetal bovine serum (FBS). Two days prior to use the PC-12 cells were differentiated by 50 ng/ml of nerve growth factor (NGF). After the cells were primed, 5 ml of trypsin was added to the culture dish to detach the cells, the cells were pelleted and re-suspended in 2 ml of DMEM with 1% HS and 50 ng/ml of nerve growth factor. Approximately, 5000 to 7000 cells were then plated on 8 well chamber Lab-Tek slides (Nuc, Naperville, Ill.) coated myelin. The cells were placed on the test substrates at 37° C. for 3-4 hours to allow the cells to settle. The original media was carefully removed by aspiration, taking care not to disrupt the cells and replaced with DMEM with 1% HS, 50 ng/ml of NGF and varying amounts of the C3, C3APLT, or C3APS, depending on the dose desired. After two days, the cells were fixed (4% paraformaldehyde and 0.5% glutaraldehyde). For control experiments with unmodified C3, NGF primed PC-12 cells were trypsinized to detach them from the culture dish, the cells were washed once with scrape loading buffer (114 mM KCL, 15 mM NaCl, 5.5 mM MgCl2, and 10 mM Tris-HCL) and then the cells were scraped with a rubber policeman into 0.5 ml of scraping buffer in the presence of 25 or 50 □g/ml (microgram/milliliter) of C3. The cells were pelleted and resuspended in 2 ml of DMEM, 1% HS and 50 ng/ml nerve growth factor before plating. At least four experiments were analyzed for each treatment. For each well, twelve images were collected with a 20.times. objective using a Zeiss Axiovert microscope. For each image, the numbers of cells with and without neurites were counted and the lengths of the neurites were determined. Since myelin is phase dense, cells plated on myelin substrates were immuno-stained with anti-.beta.III tubulin antibody before analysis. Quantitative analysis of neurite outgrowth was with the aid of Northern Eclipse software (Empix Imaging, Mississauga, Ontario, Canada). Data analysis and statistics were with Microsoft Excel.
For a fast bioassay, the compounds were tested in tissue culture as described above, except that the cells were plated on the tissue culture plastic rather than on inhibitory substrates. For these experiments the plates were fixed and the neurites counted five hours after plating the cells. The test compounds (C3APLT and C3Basic3) were able to promote faster growth on tissue culture plastic than cells plated without treatment ( FIG. 11 ).
To examine ADP ribosylation by C3, C3APLT, and C3APS, the compounds were added to PC-12 cell cultures, as described above. The cells were harvested by centrifugation, cell homogenates prepared and the proteins separated by SDS polyacrylamide gel electrophoresis. The proteins were then transferred to nitrocellulose and the Western blots probed with anti-RhoA antibody (Santa Cruz).
EXAMPLE 5
Testing Ability of C3APLT and C3APS to Override Inhibition of Multiple Growth Inhibitory Proteins
Myelin substrates were made as described in Example 4 and plated on tissue culture chamber slides. P1 to P3 rat pups were decapitated, the heads washed in ethanol and the eye removed and placed in a petri dish with Hanks buffered saline solution (HBSS, from Gibco). A hole was cut in the cornea, the lens removed, and the retina squeezed out. Typically, four retinas per preparation were used. The retinas were removed to a 15 ml tube and the volume brought to 7 ml. A further 7 ml of dissociation enzymes and papain were added. The dissociation enzyme solution was made as follows: 30 mg DL cysteine was added to a 15 ml tube (Sigma DL cystein hydrochloride), and 70 ml HBSS, 280 ul of 10 mg/ml bovine serum albumin were added and the solution mixed and pH adjusted to 7 with 0.3 N NaOH. The dissociate solution was filter-sterilized and kept frozen in 7 ml aliquots, and before use 12.5 units papain per ml (Worthington) was added. After adding the dissociation solution to the retina, the tube was incubated for 30 minutes on a rocking tray at 37° C. The retinas were then gently triturated, centrifuged and washed with HBSS. The HBSS was replaced with growth medium (DMEM (Gibco), 10% fetal bovine serum, and 50 ng/ml brain derived neurotrophic factor (BDNF) vitamins, penicillin-streptomycin, in the presence or absence of C3APLT or C3APS. Cells were plated on test substrates of myelin or CSPG in chamber slides prepared as described in Example 4, above. A quantitative analysis was completed as described for Example 4 above. Neurons were visualized by fluorescent microscopy with anti-.beta.III tubulin antibody, which detects growing retinal ganglion cells (RGCs). Results are presented in FIG. 6 .
EXAMPLE 6
Treatment of Injured Mouse Spinal Cord with C3APLT and Measurement of Recovery of Motor Function in Treated Mice
Adult Balb-c mice were anaesthetized with 0.6 ml/kg hypnorm, 2.5 mg/kg diazepam and 35 mg/kg ketamine. This does gives about 30 minutes of anaesthetic, which is sufficient for the entire operation. A segment of the thoracic spinal column was exposed by removing the vertebrae and spinus process with microrongeurs (Fine Science Tools). A spinal cord lesion was then made dorsally, extending past the central canal with fine scissors, and the lesion was recut with a fine knife. This lesion renders all of the control animals paraplegic. The paravertebral muscle were closed with reabsorbable sutures, and the skin was closed with 2.0 silk sutures. After surgery, the bladder was manually voided every 8-10 hours until the animals regained control, typically 2-3 days. Food was placed in the cage for easy access, and sponge-water used for easy accessibility of water after surgery. Also, animals received subcutaneous injection Buprenorphine (0.05 to 0.1 mg/kg) every 8-12 hours for the first 3 days. Any animals that lost 15-20% of body weight were killed.
Rho antagonists (C3 or C3-like proteins) were delivered locally to the site of the lesion by a fibrin-based tissue adhesive delivery system (McKerracher, Canadian patent application No. 2,325,842). Recombinant C3APLT was mixed with fibrinogen and thrombin in the presence of CaCl2. Fibrinogen is cleaved by thrombin, and the resulting fibrin monomers polymerize into a three-dimensional matrix. We added C3APLT as part of a fibrin adhesive, which polymerized within about 10 seconds after being placed in the injured spinal cord. We tested C3APLT applied to the spinal cord lesion site after the lesion was made. For control we injected fibrin adhesive alone, or transected the cord without further treatment. For behavioral testing, the BBB scoring method was used to examine locomotion in an open field environment (Basso (1995) 12: 1-21). Results are presented in FIG. 7 . The environment was a rubber mat approximately 4′.times.3′ in size, and animals were placed on the mat and videotaped for about 4 minutes. Care was taken not to stimulate the peroneal region or touch the animals excessively during the taping session. The video tapes were digitized and observed by two observers to assign BBB scores. The BBB score, modified for mice, was as follows:
Score
Description
1
No observable hindlimb (HL) movement.
2
Slight movement of one or two joints.
3
Extensive movement of one joint and/or slight movement of one
other joint.
4
Extensive movement of two joints.
5
Slight movement of all three joints of the HL.
6
Slight movement of two joints and extensive movement of the third.
7
Extensive movement of two joints and slight movement of the third.
8
Extensive movement of all three joints of the HL walking with no
weight support.
9
Extensive movement of all three joints, walking with weight support.
10
Frequent to consistent dorsal stepping with weight support.
11
Frequent plantar stepping with weight support.
12
Consistent plantar stepping with weight support, no coordination.
13
Consistent plantar stepping with consistent weight support,
occasional FL-HL coordination.
14
Consistent plantar stepping with consistent weight support,
frequent FL-HL coordination.
15
Consistent plantar stepping with consistent weight support,
consistent FL-HL coordination; predominant paw position
during locomotion is rotated internally or externally,
or consistent FL-HL coordination with occasional dorsal stepping.
16
Consistent plantar stepping with consistent weight support,
consistent FL-HL coordination; predominant paw position is
parallel to the body; frequent to consistent toe
drag, or curled toes, trunk instability.
17
Consistent plantar stepping with consistent weight support,
consistent FL-HL coordination; predominant paw position is
parallel to the body, no toe drag, some trunk instability.
18
Consistent plantar stepping with consistent weight support, consistent
FL-HL coordination; predominant paw position is parallel to the
body, no toe drag and consistent stability in the locomotion.
EXAMPLE 7
Treatment of Injured Mouse Spinal Cord with C3APLT and Assessment of Anatomical Recovery
Mice that received a spinal cord injury and treated as controls or with C3APLT, as described for Example 6 were assessed for morphological changes to the scar and for axon regeneration. To study axon regeneration, the corticospinal axons were identified by anterograde labeling. For anterograde labeling studies, the animals were anaesthetized as above, and the cranium over the motor cortex was removed. With the fine glass micropipetter (about 100 um in diameter) the cerebral cortex was injected with 2-4 ul of horse radish peroxidase conjugated to wheat germ agglutinin (2%), a marker that is taken up by nerve cells and transported anterogradely into the axon that extends into the spinal cord. After injection of the anterograde tracer, the cranium was replaced, and the skin closed with 5-0 silk sutures. The animals were sacrificed with chloral hydrate (4.9 mg/10 g) after 48 hours, and perfused with 4% paraformaldehyde in phosphate buffer as a fixative. The spinal cord was removed, cryoprotected with sucrose and cryostat sections placed on slides for histological examination.
EXAMPLE 8
DNA and Protein Sequence Details of C3-TL
The Tat coding sequence was obtained by polymerase chain reaction of the plasmid SVCMV-TAT (obtained form Dr. Eric Cohen, Universite de Montreal) that contains the entire HIV-1 Tat coding sequence. To isolate the transport sequence of the Tat protein, PCR was used. The first primer (5′GAATCCAAGCACCAGGAAGTCAGCC 3′ (SEQ ID NO.: 11)) and the second primer (5′ ACC AGCCACCACCTTCTGATA 3′ (SEQ ID NO.: 12)) used corresponded to amino acids 27 to 72 of the HIV Tat protein. Upon verification and purification, the PCR product was sub cloned into a pSTBlue-1 blunt vector. This transport segment of the Tat protein was then cloned into pGEX-4T/C3 at the 3′ end of C3, using the restriction sites EcoR I and Sac I. The new C3-Tat fusion protein was called C3-TL. Recombinant protein was made as described in Example 3.
DNA Sequence of C3-TL (SEQ ID NO.: 13)
ggatcctcta gagtcgacct gcaggcatgc aatgcttatt ccattaatca aaaggcttat
60
tcaaatactt accaggagtt tactaatatt gatcaagcaa aagcttgggg taatgctcag
120
tataaaaagt atggactaag caaatcagaa aaagaagcta tagtatcata tactaaaagc
180
gctagtgaaa taaatggaaa gctaagacaa aataagggag ttatcaatgg atttccttca
240
aatttaataa aacaagttga acttttagat aaatctttta ataaaatgaa gacccctgaa
300
aatattatgt tatttagagg cgacgaccct gcttatttag gaacagaatt tcaaaacact
360
cttcttaatt caaatggtac aattaataaa acggcttttg aaaaggctaa agctaagttt
420
ttaaataaag atagacttga atatggatat attagtactt cattaatgaa tgtctctcaa
480
tttgcaggaa gaccaattat tacacaattt aaagtagcaa aaggctcaaa ggcaggatat
540
attgacccta ttagtgcttt tcagggacaa cttgaaatgt tgcttcctag acatagtact
600
tatcatatag acgatatgag attgtcttct gatggtaaac aaataataat tacagcaaca
660
atgatgggca cagctatcaa tcctaaagaa ttcaagcatc caggaagtca gcctaaaact
720
gcttgtacca attgctattg taaaaagtgt tgctttcatt gccaagtttg tttcataaca
780
aaagccttag gcatctccta tggcaggaag cggagacagc gacgaagagc tcatcagaac
840
agtcagactc atcaagcttc tctatcaaag cagtaa
876
The TL transport peptide sequence by itself is as follows: (SEQ ID NO.: 46)
Lys His Pro Gly Ser Gln Pro Lys Thr Ala Cys Thr
1 5 10
Asn Cys Tyr Cys Lys Lys Cys Cys Phe His Cys Gln
15 20
Val Cys Phe Ile Thr Lys Ala Leu Gly Ile Ser Tyr
25 30 35
Gly Arg Lys Arg Arg Gln Arg Arg Ala His Gln Asn
40 45
Ser Gln Thr His Gln Ala Ser Leu Ser Lys Gln
50 55
The Protein Sequence of C3-TL (SEQ ID NO.: 14)
Gly Ser Ser Arg Val Asp Leu Gln Ala Cys Asn Ala Tyr Ser Ile Asn
1 5 10 15
Gln Lys Ala Tyr Ser Asn Thr Tyr Gln Glu Phe Thr Asn Ile Asp Gln
20 25 30
Ala Lys Ala Trp Gly Asn Ala Gln Tyr Lys Lys Tyr Gly Leu Ser Lys
35 40 45
Ser Glu Lys Glu Ala Ile Val Ser Tyr Thr Lys Ser Ala Ser Glu Ile
50 55 60
Asn Gly Lys Leu Arg Gln Asn Lys Gly Val Ile Asn Gly Phe Pro Ser
65 70 75 80
Asn Leu Ile Lys Gln Val Glu Leu Leu Asp Lys Ser Phe Asn Lys Met
85 90 95
Lys Thr Pro Glu Asn Ile Met Leu Phe Arg Gly Asp Asp Pro Ala Tyr
100 105 110
Leu Gly Thr Glu Phe Gln Asn Thr Leu Leu Asn Ser Asn Gly Thr Ile
115 120 125
Asn Lys Thr Ala Phe Glu Lys Ala Lys Ala Lys Phe Leu Asn Lys Asp
130 135 140
Arg Leu Glu Tyr Gly Tyr Ile Ser Thr Ser Leu Met Asn Val Ser Gln
145 150 155 160
Phe Ala Gly Arg Pro Ile Ile Thr Gln Phe Lys Val Ala Lys Gly Ser
165 170 175
Lys Ala Gly Tyr Ile Asp Pro Ile Ser Ala Phe Gln Gly Gln Leu Glu
180 185 190
Met Leu Leu Pro Arg His Ser Thr Tyr His Ile Asp Asp Met Arg Leu
195 200 205
Ser Ser Asp Gly Lys Gln Ile Ile Ile Thr Ala Thr Met Met Gly Thr
210 215 220
Ala Ile Asn Pro Lys Glu Phe Lys His Pro Gly Ser Gln Pro Lys Thr
225 230 235 240
Ala Cys Thr Asn Cys Tyr Cys Lys Lys Cys Cys Phe His Cys Gln Val
245 250 255
Cys Phe Ile Thr Lys Ala Leu Gly Ile Ser Tyr Gly Arg Lys Arg Arg
260 265 270
Gln Arg Arg Arg Ala His Gln Asn Ser Gln Thr His Gln Ala Ser Leu
275 280 285
Ser Lys Gln
290
Physical Characteristics
Molecular Weight 32721.40 Daltons 291 Amino Acids 43 Strongly Basic(+) Amino Acids (K,R) 21 Strongly Acidic(−) Amino Acids (D,E) 82 Hydrophobic Amino Acids (A, I, L, F, W, V) 104 Polar Amino Acids (N, C, Q, S, T, Y) 9.688 Isolectric Point 22.655 Charge at PH 7.0 Total Number of Bases Translated is 876
% A = 37.44
[328]
% G = 17.58
[154]
% T = 28.31
[248]
% C = 16.67
[146]
EXAMPLE 9
DNA and Protein Sequence Details of C3-TS
A shorter Tat construct was also made (C3-TS). To make the shorter C3 Tat fusion protein the following oligonucleotides were 5′AAT TCT ATG GTC GTA AAA AAC GTC GTC AAC GTC GTC GTG 3′ (SEQ ID NO.: 15) and 5′ GAT ACC AGC ATT TTT TGC AGC AGT TGC AGC AGC ACA GCT 3′ (SEQ ID NO.: 16). The two oligonucleotide strands were annealed together by combining equal amounts of the oligonucleotides, heating at 72° C. for 5 minutes and then letting the oligonucleotide solution cool at room temperature for 15 minutes. The oligonucleotides were ligated into the pGEX4T/C3 vector at the 3′ end of C3. The construct was sequenced. All plasmids were transformed into XL-1 blue competent cells. Recombinant protein was made as described in Example 3.
Nucleotide Sequence of C3-TS (SEQ ID NO.: 17)
ggatcctcta gagtcgacct gcaggcatgc aatgcttatt ccattaatca aaaggcttat
60
tcaaatactt accaggagtt tactaatatt gatcaagcaa aagcttgggg taatgctcag
120
tataaaaagt atggactaag caaatcagaa aaagaagcta tagtatcata tactaaaagc
180
gctagtgaaa taaatggaaa gctaagacaa aataagggag ttatcaatgg atttccttca
240
aatttaataa aacaagttga acttttagat aaatctttta ataaaatgaa gacccctgaa
300
aatattatgt tatttagagg cgacgaccct gcttatttag gaacagaatt tcaaaacact
360
cttcttaatt caaatggtac aattaataaa acggcttttg aaaaggctaa agctaagttt
420
ttaaataaag atagacttga atatggatat attagtactt cattaatgaa tgtctctcaa
480
tttgcaggaa gaccaattat tacacaattt aaagtagcaa aaggctcaaa ggcaggatat
540
attgacccta ttagtgcttt tcagggacaa cttgaaatgt tgcttcctag acatagtact
600
tatcatatag acgatatgag attgtcttct gatggtaaac aaataataat tacagcaaca
660
atgatgggca cagctatcaa tcctaaagaa ttctatggtg ctaaaaaacg tcgtcaacgt
720
cgtcgtgtcg actcgagcgg cccgcatcgt gactga
756
The TS transport peptide sequence by itself is as follows: (SEQ ID NO.: 47)
Tyr Gly Ala Lys Lys Arg Arg Gln Arg Arg Arg Val
1 5 10
Asp Ser Ser Gly Pro His Arg Asp
15 20
The Protein Sequence of C3-TS (SEQ ID NO.: 18)
Gly Ser Ser Arg Val Asp Leu Gln Ala Cys Asn Ala Tyr Ser Ile Asn
1 5 10 15
Gln Lys Ala Tyr Ser Asn Thr Tyr Gln Glu Phe Thr Asn Ile Asp Gln
20 25 30
Ala Lys Ala Trp Gly Asn Ala Gln Tyr Lys Lys Tyr Gly Leu Ser Lys
35 40 45
Ser Glu Lys Glu Ala Ile Val Ser Tyr Ile Lys Ser Ala Ser Glu Thr
50 55 60
Asn Gly Lys Leu Arg Gln Asn Lys Gly Val Ile Asn Gly Phe Pro Ser
65 70 75 80
Asn Leu Ile Lys Gln Val Glu Leu Leu Asp Lys Ser Phe Asn Lys Met
85 90 95
Lys Thr Pro Glu Asn Ile Met Leu Phe Arg Gly Asp Asp Pro Ala Tyr
100 105 110
Leu Gly Thr Glu Phe Gln Asn Thr Leu Leu Asn Ser Asn Gly Thr Ile
115 120 125
Asn Lys Thr Ala Phe Glu Lys Ala Lys Ala Lys Phe Leu Asn Lys Asp
130 135 140
Arg Leu Glu Tyr Gly Tyr Ile Ser Thr Ser Leu Met Asn Val Ser Gln
145 150 155 160
Phe Ala Gly Arg Pro Ile Ile Thr Gln Phe Lys Val Ala Lys Gly Ser
165 170 175
Lys Ala Gly Tyr Ile Asp Pro Ile Ser Ala Phe Gln Gly Gln Leu Glu
180 185 190
Met Leu Leu Pro Arg His Ser Thr Tyr His Ile Asp Asp Met Arg Leu
195 200 205
Ser Ser Asp Gly Lys Gln Ile Ile Ile Thr Ala Thr Met Met Gly Thr
210 215 220
Ala Ile Asn Pro Lys Glu Phe Tyr Gly Ala Lys Lys Arg Arg Gln Arg
225 230 235 240
Arg Arg Val Asp Ser Ser Gly Pro His Arg Asp
245 250
Physical Characteristics
Molecular Weight 26866.62 Daltons 238 Amino Acids 36 Strongly Basic(+) Amino Acids (K,R) 21 Strongly Acidic(−) Amino Acids (D,E) 71 Hydrophobic Amino Acids (A, I, L, F, W, V) 78 Polar Amino Acids (N, C, Q, S, T, Y) 9.802 Isolectric Point 15.212 Charge at PH 7.0 Total Number of Bases Translated is 717
% A = 38.91
[279]
% G = 17.43
[125]
% T = 28.45
[204]
% C = 15.20
[109]
EXAMPLE 10
The following example illustrates how a coding sequence can be modified without affecting the efficacy of the translated protein. The example shows modifications to C3Basic3 that would not affect the activity. Sequences may include the entire GST sequence, as shown here that includes the start site, which would not be removed enzymatically. Also, the transport sequence shown in this example has changes in amino acid composition surrounding the active sequence due to a difference in the cloning strategy, and the His tag has been omitted. However, the active region is: R R K Q R R K R R (SEQ ID NO:53). This sequence is contained in the C3Basic3, and is the active transport sequence in the sequence below. Also note that the C-terminal region of the protein after this active region differs from C3Basic3. That is because the cloning strategy was changed, the restriction sites differ, and therefore non-essential amino acids 3′ terminal to the transport sequence are transplanted and included in the protein.
Nucleic Acid Sequence: (SEQ ID NO.: 19)
1413 base pairs single strand linear sequence
atgtccccta tactaggtta ttggaaaatt aagggccttg tgcaacccac tcgacttctt
60
ttggaatatc ttgaagaaaa atatgaagag catttgtatg agcgcgatga aggtgataaa
120
tggcgaaaca aaaagtttga attgggtttg gagtttccca atcttcctta ttatattgat
180
ggtgatgtta aattaacaca gtctatggcc atcatacgtt atatagctga caagcacaac
240
atgttgggtg gttgtccaaa agagcgtgca gagatttcaa tgcttgaagg agcggttttg
300
gatattagat acggtgtttc gagaattgca tatagtaaag actttgaaac tctcaaagtt
360
gattttctta gcaagctacc tgaaatgctg aaaatgttcg aagatcgttt atgtcataaa
420
acatatttaa atggtgatca tgtaacccat cctgacttca tgttgtatga cgctcttgat
480
gttgttttat acatggaccc aatgtgcctg gatgcgttcc caaaattagt ttgttttaaa
540
aaacgtattg aagctatccc acaaattgat aagtacttga aatccagcaa gtatatagca
600
tggcctttgc agggctggca agccacgttt ggtggtggcg accatcctcc aaaatcggat
660
ctggttccgc gtggatcctc tagagtcgac ctgcaggcat gcaatgctta ttccattaat
720
caaaaggctt attcaaatac ttaccaggag tttactaata ttgatcaagc aaaagcttgg
780
ggtaatgctg agtataaaaa gtatggacta agcaaatcag aaaaagaagc tatagtatca
840
tatactaaaa gcgctagtga aataaatgga aagctaagac aaaataaggg agttatcaat
900
ggatttcctt caaatttaat aaaacaagtt gaacttttag ataaatcttt taataaaatg
960
aagacccctg aaaatattat gttatttaga ggcgaggagc ctgcttattt aggaacagaa
1020
tttcaaaaca ctcttcttaa ttcaaatggt acaattaata aaacggcttt tgaaaaggct
1080
aaagctaagt ttttaaataa agatagactt gaatatggat atattagtac ttcattaatg
1140
aatgtttctc aatttgcagg aagaccaatt attacaaaat ttaaagtagc aaaaggctca
1200
aaggcaggat atattgagcc tattagtgct tttcagggac aacttgaaat gttgcttcct
1260
agacatagta cttatcatat agacgatatg agattgtctt ctgatggtaa acaaataata
1320
attacagcaa caatgatggg cacagctatc aatcctaaag aattcagaag gaaacaaaga
1380
agaaaaagaa gactgcaggc ggccgcatcg tga
1413
Amino Acid Sequence (SEQ ID NO: 20)
479 amino acids linear, single strand
Met Ser Pro Ile Leu Gly Tyr Trp Lys Ile Lys Gly Leu Val Gln Pro
1 5 10 15
Thr Arg Leu Leu Leu Glu Tyr Leu Glu Glu Lys Tyr Glu Glu His Leu
20 25 30
Tyr Glu Arg Asp Glu Gly Asp Lys Trp Arg Asn Lys Lys Phe Glu Leu
35 40 45
Gly Leu Glu Phe Pro Asn Leu Pro Tyr Tyr Ile Asp Gly Asp Val Lys
50 55 60
Leu Thr Gln Ser Met Ala Ile Ile Arg Tyr Ile Ala Asp Lys His Asn
65 70 75 80
Met Leu Gly Gly Cys Pro Lys Glu Arg Ala Glu Ile Ser Met Leu Glu
85 90 95
Gly Ala Val Leu Asp Ile Arg Tyr Gly Val Ser Arg Ile Ala Tyr Ser
100 105 110
Lys Asp Phe Glu Thr Leu Lys Val Asp Phe Leu Ser Lys Leu Pro Glu
115 120 125
Met Leu Lys Met Phe Glu Asp Arg Leu Cys His Lys Thr Tyr Leu Asn
130 135 140
Gly Asp His Val Thr His Pro Asp Phe Met Leu Tyr Asp Ala Leu Asp
145 150 155 160
Val Val Leu Tyr Met Asp Pro Met Cys Leu Asp Ala Phe Pro Lys Leu
165 170 175
Val Cys Phe Lys Lys Arg Ile Glu Ala Ile Pro Gln Ile Asp Lys Tyr
180 185 190
Leu Lys Ser Ser Lys Tyr Ile Ala Trp Pro Leu Gln Gly Trp Gln Ala
195 200 205
Thr Phe Gly Gly Gly Asp His Pro Pro Lys Ser Asp Leu Val Pro Arg
210 215 220
Gly Ser Ser Arg Val Asp Leu Gln Ala Cys Asn Ala Tyr Ser Ile Asn
225 230 235 240
Gln Lys Ala Tyr Ser Asn Thr Tyr Gln Glu Phe Thr Asn Thr Asp Gln
245 250 255
Ala Lys Ala Trp Gly Asn Ala Gln Tyr Lys Lys Tyr Gly Leu Ser Lys
260 265 270
Ser Glu Lys Glu Ala Ile Val Ser Tyr Thr Lys Ser Ala Ser Glu Thr
275 280 285
Asn Gly Lys Leu Arg Gln Asn Lys Gly Val Ile Asn Gly Phe Pro Ser
290 295 300
Asn Leu Ile Lys Gln Val Glu Leu Leu Asp Lys Ser Phe Asn Lys Met
305 310 315 320
Lys Thr Pro Glu Asn Ile Met Leu Phe Arg Gly Asp Asp Pro Ala Tyr
325 330 335
Leu Gly Thr Glu Phe Gln Asn Thr Leu Leu Asn Ser Asn Gly Thr Ile
340 345 350
Asn Lys Thr Ala Phe Glu Lys Ala Lys Ala Lys Phe Leu Asn Lys Asp
355 360 365
Arg Leu Glu Tyr Gly Tyr Ile Ser Thr Ser Leu Met Asn Val Ser Gln
370 375 380
Phe Ala Gly Arg Pro Ile Ile Thr Arg Phe Lys Val Ala Lys Gly Ser
385 390 395 400
Lys Ala Gly Tyr Ile Asp Pro Ile Ser Ala Phe Gln Gly Gln Leu Glu
405 410 415
Met Leu Leu Pro Arg His Ser Thr Tyr His Asp Asp Met Arg Leu Ser
420 425 430
Ser Asp Gly Lys Gln Ile Ile Ile Thr Ala Thr Met Met Gly Thr Ala
435 440 445
Ile Asn Pro Lys Glu Phe Arg Arg Lys Gln Arg Arg Lys Arg Arg Leu
450 455 460
Gln Ala Ala Ala Ser
465
Physical Characteristics
Molecular Weight 53813.02 Daltons 470 Amino Acids 68 Strongly Basic(+) Amino Acids (K,R) 55 Strongly Acidic(−) Amino Acids (D,E) 149 Hydrophobic Amino Acids (A, I, L, F, W, V) 121 Polar Amino Acids (N, C, Q, S, T, Y) 9.137 Isolectric Point 14.106 Charge at PH 7.0 Total Number of Bases Translated is 1413
% A = 34.61
[489]
% G = 19.75
[279]
% T = 29.51
[417]
% C = 15.99
[226]
% Ambiguous = 0.14
[2]
% A + T = 64.12
[906]
% C + G = 35.74
[505]
Davis, Botstein, Roth Melting Temp C. 79.20
EXAMPLE 11
Additional Chimeric C3 Proteins that would be Effective to Stimulate Repair in the CNS
The following sequences could be added to the amino terminal or carboxy terminal of C3 or a truncated C3 that retains its enzymatic activity.
(1) Sequences of polyarginine as described (Wender, et al. (2000) 97: 13003-8.). These could be from 6 to 9 or more arginines. (2) Sequences of poly-lysine (3) Sequences of poly-histidine (4) Sequences of arginine and lysine mixed. (5) Basic stretches of amino acids containing non-basic amino acids stretch where the sequence added retains transport characteristics. (6) Sequences of 5-15 amino acids containing at least 50% basic amino acids (7) Sequences longer than 15-30 amino acids containing at least 30% basic amino acids. (8) Sequences longer than 50 amino acids containing at least 18% basic amino acids. (9) Any of the above where the amino acids are chemically modified, such as by addition of cyclohexyl side chains, other side chains, different alkyl spacers. (10) Sequences that have proline residues with helix-breaking propensity to act as effective transporters.
EXAMPLE 12
Additional Chimeric C3 Proteins that would be Effective to Stimulate Repair in the CNS
C3Basic1: C3 fused to a randomly designed basic tail
C3Basic2: C3 fused to a randomly designed basic tail
C3 Basic3: C3 fused to the reverse Tat sequence
We have designed the following DNA encoding a chimeric C3 with membrane transport properties. The protein is designated C3Basic1. This sequence was designed with C3 fused to a random basic sequence. The construct was made to encode the peptide given below.
(SEQ ID NO.: 21)
Lys Arg Arg Arg Arg Arg Pro Lys Lys Arg Arg Arg
1 5 10
Ala Lys Arg Arg
15
The construct was made by synthesizing the two oligonucleotides given below, annealing them together, and ligating them into the pGEX-4T/C3 vector with an added histidine tag.
(SEQ ID NO: 22)
aagagaaggc gaagaagacc taagaagaga cgaagggcga
48
agaggaga
(SEQ ID NO: 23)
ttctcttccg cttcttctgg attcttctct gcttcccgct
48
tctcctct
DNA Sequence of C3Basic1 (SEQ ID NO: 24)
ggatcctcta gagtcgacct gcaggcatgc aatgcttatt ccattaatca aaaggcttat
60
tcaaatactt accaggagtt tactaatatt gatcaagcaa aagcttgggg taatgctcag
120
tataaaaagt atggactaag caaatcagaa aaagaagcta tagtatcata tactaaaagc
180
gctagtgaaa taaatggaaa gctaagacaa aataagggag ttatcaatgg atttccttca
240
aatttaataa aacaagttga acttttagat aaatctttta ataaaatgaa gacccctgaa
300
aatattatgt tatttagagg cgacgaccct gcttatttag gaacagaatt tcaaaacact
360
cttcttaatt caaatggtac aattaataaa acggcttttg aaaaggctaa agctaagttt
420
ttaaataaag atagacttga atatggatat attagtactt cattaatgaa tgtttctcaa
480
tttgcaggaa gaccaattat tacaaaattt aaagtagcaa aaggctcaaa ggcaggatat
540
attgacccta ttagtgcttt tcagggacaa cttgaaatgt tgcttcctag acatagtact
600
tatcatatag acgatatgag attgtcttct gatggtaaac aaataataat tacagcaaca
660
atgatgggca cagctatcaa tcctaaagaa ttcaagagaa ggcgaagaag acctaagaag
720
agacgaaggg cgaagaggag acaccaccac caccaccacg tcgactcgag cggccgcatc
780
gtgactgact ga
792
Protein Sequence of C3Basic1 (SEQ ID NO: 25)
GSSRVDLQACNAYSTNQKAYSNTYQEFTNDQAKAWGNAQYKKYGLSKSEK
EAIVSYTKSASEINGKLRQNKGVINGFPSNUKQVELLDKSFNKMKTPENI
MLFRGDDPAYLGTEFQNTLLNSNGTINKTAFEKAKAKFLNKDRLEYGYIS
TSLMNVSQFAGRPIITKFKVAKGSKAGYDPISAFQGQLEMLLPRHSTYHD
DMRLSSDGKIIITATMMGTAINPKEFKRRRRRPKKRRRAKRRHHHHHHVD
SSGRIVTD.
Physical Characteristics
Molecular Weight 29897.03 Daltons 263 Amino Acids 44 Strongly Basic(+) Amino Acids (K,R) 23 Strongly Acidic(−) Amino Acids (D,E) 75 Hydrophobic Amino Acids (A, I, L, F, W, V) 79 Polar Amino Acids (N, C, Q, S, T, Y) 10.024 Isolectric Point 22.209 Charge at PH 7.0 Davis, Botstein, Roth Melting Temp C. 78.56
EXAMPLE 13
Additional Chimeric C3 Protein that would be Effective to Stimulate Repair in the CNS
We have designed the following DNA encoding a chimeric C3 with membrane transport properties. The protein is designated C3Basic2. This sequence was designed with C3 fused to a random basic sequence. The construct was made to encode the peptide given below.
(SEQ ID NO.:26)
Lys Arg Arg Arg Arg Lys Lys Arg Arg Gln Arg Arg
1 5 10
Arg
The construct was made by synthesizing the two oligonucleotides given below, annealing them together, and ligating them into the pGEX4T/C3 vector with an added histidine tag.
(SEQ ID NO.: 27)
aagcgtcgac gtagaaagaa acgtagacag cgtagacgt
39
(SEQ ID NO.: 28)
ttcgcagctg catctttctt tgcatctgtc gcatctgca
39
DNA Sequence of C3Basic2 (SEQ ID NO.: 29)
5′ GGA TCC TCT AGA GTC GAC CTG CAG GCA TGC AAT GCT
TAT TCC ATT AAT CAA AAG GCT TAT TCA AAT ACT TAC
CAG GAG TTT ACT AAT ATT GAT CAA GCA AAA GCT TGG
GGT AAT GCT CAG TAT AAA AAG TAT GGA CTA AGC AAA
TCA GAA AAA GPA GCT ATA GTA TCA TAT ACT AAA AGC
GCT AGT GAA ATA AAT GGA AAG CTA AGA CAA AAT AAG
GGA GTT ATC AAT GGA TTT CCT TCA AAT TTA ATA AAA
CAA GTT GAA CTT TTA GAT PAA TCT TTT AAT AAA ATG
AAG ACC CCT GAA AAT ATT ATG TTA TTT AGA GGC GAC
GAC CCT GCT TAT TTA GGA ACA GPA TTT CPA AAC ACT
CTT CTT AAT TCA AAT GGT ACA ATT AAT AAA ACG GCT
TTT GAA AAG GCT AAA GCT AAG TTT TTA AAT AAA GAT
AGA CTT GAA TAT GGA TAT ATT AGT ACT TCA TTA ATG
AAT GTT TCT CAA TTT GCA GGA AGA CCA ATT ATT ACA
AAA TTT AAA GTA GCA AAA GGC TCA AAG GCA GGA TAT
ATT GAC CCT ATT AGT GCT TTT CAG GGA CAA CTT GAA
ATG TTG CTT CCT AGA CAT AGT ACT TAT CAT ATA GAC
GAT ATG AGA TTG TCT TCT GAT GGT AAA CAA ATA ATA
ATT ACA GCA ACA ATG ATG GGC ACA GCT ATC AAT CCT
AAA GAA TTC AAG CGT CGA CGT AGA AAG AAA CGT AGA
CAG CGT AGA CGT CAC CAC CAC CAC CAC CAC GTC GAC
TCG AGC GGC CGC ATC GTG ACT GAC TGA 3′
Protein Sequence of C3Basic2 (SEQ ID NO.: 30)
Gly Ser Ser Arg Val Asp Leu Gln Ala Cys Asn Ala Tyr Ser Ile Asn
1 5 10 15
Gln Lys Ala Tyr Ser Asn Thr Tyr Gln Glu Phe Thr Asn Asp Gln Ala
20 25 30
Lys Ala Trp Gly Asn Ala Gln Tyr Lys Lys Tyr Gly Leu Ser Lys Ser
35 40 45
Glu Lys Glu Ala Ile Val Ser Tyr Thr Lys Ser Ala Ser Glu Thr Asn
50 55 60
Gly Lys Leu Arg Gln Asn Lys Gly Val Thr Asn Gly Phe Pro Ser Asn
65 70 75 80
Leu Ile Lys Gln Val Glu Leu Leu Asp Lys Ser Phe Asn Xaa Met Lys
85 90 95
Thr Pro Glu Asn Thr Met Leu Phe Arg Gly Asp Asp Pro Ala Tyr Leu
100 105 110
Gly Thr Glu Phe Gln Asn Thr Leu Leu Asn Ser Asn Gly Thr Ile Asn
115 120 125
Lys Thr Ala Phe Glu Lys Ala Lys Ala Lys Phe Leu Asn Lys Asp Arg
130 135 140
Leu Glu Tyr Gly Tyr Ile Ser Thr Ser Leu Met Asn Val Ser Gln Phe
145 150 155 160
Ala Gly Arg Pro Ile Ile Thr Lys Phe Lys Val Ala Lys Gly Ser Lys
165 170 175
Ala Gly Tyr Ile Asp Pro Ile Ser Ala Phe Gln Gly Gln Leu Glu Met
180 185 190
Leu Leu Pro Arg His Ser Thr Tyr His Thr Asp Asp Met Arg Leu Ser
195 200 205
Ser Asp Gly Lys Gln Ile Ile Ile Thr Ala Thr Met Met Gly Thr Ala
210 215 220
Thr Asn Pro Lys Glu Phe Lys Arg Arg Arg Arg Lys Lys Arg Arg Gln
225 230 235 240
Arg Arg Arg His His His His His His Val Asp Ser Ser Gly Arg Ile
245 250 255
Val Thr Asp
Physical Characteristics
Molecular Weight 29572.61 Daltons 260 Amino Acids 42 Strongly Basic(+) Amino Acids (K,R) 23 Strongly Acidic(−) Amino Acids (D,E) 74 Hydrophobic Amino Acids (A, I, L, F, W, V) 80 Polar Amino Acids (N, C, Q, S, T, Y) 9.956 Isolectric Point 20.210 Charge at PH 7.0 Davis, Botstein, Roth Melting Temp C. 78.45
EXAMPLE 14
Additional Chimeric C3 Protein that would be Effective to Stimulate Repair in the CNS
We have designed the following DNA encoding a chimeric C3 with membrane transport properties. The protein is designated C3Basic3. This sequence was designed with C3 fused to a reverse Tat sequence. The construct was made to encode the peptide given below
Arg Arg Lys Gln Arg Arg Lys Arg Arg
(SEQ ID NO:31)
1 5
The construct was made by synthesizing the two oligonucleotides given below, annealing them together, and ligating them into the pGEX4T/C3 vector with an added histidine tag, then subcloning in pGEX-4T/C3.
agaaggaaac aaagaagaaa aagaaga
27
(SEQ ID NO.: 32)
tcttcctttg tttcttcttt ttcttct
27
(SEQ ID NO.: 33)
DNA Sequence of C3Basic3 (SEQ ID NO.: 34)
ggatcctcta gagtcgacct gcaggcatgc aatgcttatt ccattaatca aaaggcttat
60
tcaaatactt accaggagtt tactaatatt gatcaagcaa aagcttgggg taatgctcag
120
tataaaaagt atggactaag caaatcagaa aaagaagcta tagtatcata tactaaaagc
180
gctagtgaaa taaatggaaa gctaagacaa aataagggag ttatcaatgg atttccttca
240
aatttaataa aacaagttga acttttagat aaatctttta ataaaatgaa gacccctgaa
300
aatattatgt tatttagagg cgacgaccct gcttatttag gaacagaatt tcaaaacact
360
cttcttaatt caaatggtac aattaataaa acggcttttg aaaaggctaa agctaagttt
420
ttaaataaag atagacttga atatggatat attagtactt cattaatgaa tgtttctcaa
480
tttgcaggaa gaccaattat tacaaaattt aaagtagcaa aaggctcaaa ggcaggatat
540
attgacccta ttagtgcttt tcagggacaa cttgaaatgt tgcttcctag acatagtact
600
tatcatatag acgatatgag attgtcttct gatggtaaac aaataataat tacagcaaca
660
atgatgggca cagctatcaa tcctaaagaa ttcagaagga aacaaagaag aaaaagaaga
720
caccaccacc accaccacgt cgactcgagc ggccgcatcg tgactgactg a
771
Protein Sequence of C3Basic3 (SEQ ID NO.: 35)
Gly Ser Ser Arg Val Asp Leu Gln Ala Cys Asn Ala Tyr Ser Thr Asn
1 5 10 15
Gln Lys Ala Tyr Ser Asn Thr Tyr Gln Glu Phe Thr Asn Ile Asp Gln
20 25 30
Ala Lys Ala Trp Gly Asn Ala Gln Tyr Lys Lys Tyr Gly Leu Ser Lys
35 40 45
Ser Glu Lys Ile Glu Ala Ile Val Ser Tyr Thr Lys Ser Ala Ser Glu
50 55 60
Ile Asn Gly Lys Leu Arg Gln Asn Lys Gly Val Ile Asn Gly Phe Pro
65 70 75 80
Ser Asn Ile Lys Gln Val Glu Leu Leu Asp Lys Ser Phe Asn Lys Met
85 90 95
Lys Thr Pro Glu Asn Ile Met Leu Phe Arg Gly Asp Asp Pro Ala Tyr
100 105 110
Leu Gly Thr Glu Phe Gln Asn Thr Leu Leu Asn Ser Asn Gly Thr Thr
115 120 125
Asn Lys Thr Ala Phe Glu Lys Ala Lys Ala Lys Phe Leu Asn Lys Asp
130 135 140
Arg Leu Glu Tyr Gly Tyr Ile Ser Thr Ser Leu Met Asn Val Ser Gln
145 150 155 160
Phe Ala Gly Arg Leu Pro Ile Ile Thr Arg Phe Lys Val Ala Lys Gly
165 170 175
Ser Lys Ala Gly Tyr Ile Asp Pro Ile Ser Ala Phe Gln Gly Gln Leu
180 185 190
Glu Met Leu Leu Ala Arg His Ser Thr Tyr His Ile Asp Asp Met Arg
195 200 205
Leu Ser Ser Asp Gly Lys Gln Ile Ile Ile Thr Ala Thr Met Met Gly
210 215 220
Thr Ala Ile Asn Pro Lys Glu Phe Arg Arg Lys Gln Arg Arg Lys Arg
225 230 235 240
Arg His His His His His His Val Asp Ser Ser Gly Arg Ile Val Thr
245 250 255
Asp
Physical Characteristics
Molecular Weight 29441.47 Daltons 260 Amino Acids 39 Strongly Basic(+) Amino Acids (K,R) 23 Strongly Acidic(−) Amino Acids (D,E) 76 Hydrophobic Amino Acids (A, I, L, F, W, V) 80 Polar Amino Acids (N, C, Q, S, T, Y) 9.833 Isolectric Point 17.211 Charge at PH 7.0 Davis, Botstein, Roth Melting Temp C. 78.29
EXAMPLE 15
Sequences for C3APLT
One of the clones that was selected from the subcloning of C3APL into pGEX encoded a protein that was not the expected size but had good biological activity. This clone that had a frameshift mutation leading to a truncation, and this clone was called C3APLT. The clone was resequenced and the chromatograms analyzed to confirm the sequence. To confirm the sequences of C3APLT, the coding sequence from both strands of pGEX-4T/C3APLT were sequenced by double strand sequencing of the full length of the clone (BioS&T, Montreal, Quebec).
The DNA Sequence for C3APLT is as follows: (SEQ ID NO.: 36)
ggatcctcta gagtcgacct gcaggcatgc aatgcttatt ccattaatca aaaggcttat
60
tcaaatactt accaggagtt tactaatatt gatcaagcaa aagcttgggg taatgctcag
120
tataaaaagt atggactaag caaatcagaa aaagaagcta tagtatcata tactaaaagc
180
gctagtgaaa taaatggaaa gctaagacaa aataagggag ttatcaatgg atttccttca
240
aatttaataa aacaagttga acttttagat aaatctttta ataaaatgaa gacccctgaa
300
aatattatgt tatttagagg cgacgaccct gcttatttag gaacagaatt tcaaaacact
360
cttcttaatt caaatggtac aattaataaa acggcttttg aaaaggctaa agctaagttt
420
ttaaataaag atagacttga atatggatat attagtactt cattaatgaa tgtttctcaa
480
tttgcaggaa gaccaattat tacaaaattt aaagtagcaa aaggctcaaa ggcaggatat
540
attgacccta ttagtgcttt tgcaggacaa cttgaaatgt tgcttcctag acatagtact
600
tatcatatag acgatatgag attgtcttct gatggtaaac aaataataat tacagcaaca
660
atgatgggca cagctatcaa tcctaaagaa ttcgtgatga atcccgcaaa cgcgcaaggc
720
agacatacac ccggtaccag actctagagc tagagaagga gtttcacttc aatcgctact
780
tgacccgtcg gcgaaggatc gagatcgccc acgccctgtg cctcacggag cgccagataa
840
agatttggtt ccagaatcgg cgcatgaagt ggaagaagga gaactga
887
The APLT transport peptide sequence by itself is as follows (SEQ ID NO.: 48):
Val Met Asn Pro Ala Asn Ala Gln Gly Arg His Thr
1 5 10
Pro Gly Thr Arg Leu
15
The Protein Sequence for C3APLT is as follows: (SEQ ID NO.: 37)
Gly Ser Ser Arg Val Asp Leu Gln Ala Cys Asn Ala Tyr Ser Ile Asn
1 5 10 15
Gln Lys Ala Tyr Ser Asn Thr Tyr Gln Glu Phe Thr Asn Ile Asp Gln
20 25 30
Ala Lys Ala Trp Gly Asn Ala Gln Tyr Lys Lys Tyr Gly Leu Ser Lys
35 40 45
Ser Glu Lys Ile Glu Ala Ile Val Ser Tyr Thr Lys Ser Ala Ser Glu
50 55 60
Ile Asn Gly Lys Leu Arg Gln Asn Lys Gly Val Ile Asn Gly Phe Pro
65 70 75 80
Ser Asn Leu Ile Lys Gln Val Glu Leu Leu Asp Lys Ser Phe Asn Lys
85 90 95
Met Lys Thr Pro Glu Asn Ile Met Leu Phe Arg Gly Asp Asp Pro Ala
100 105 110
Tyr Leu Gly Thr Glu Phe Gln Asn Thr Leu Leu Asn Ser Asn Gly Thr
115 120 125
Ile Asn Lys Thr Ala Phe Glu Lys Ala Lys Ala Lys Phe Leu Asn Ile
130 135 140
Lys Asp Arg Leu Glu Tyr Gly Tyr Ile Ser Thr Ser Leu Met Asn Val
145 150 155 160
Ser Gln Phe Ala Gly Arg Pro Ile Ile Thr Lys Phe Lys Val Ala Lys
165 170 175
Gly Ser Lys Ala Gly Tyr Ile Asp Pro Ile Ser Ala Phe Ala Gly Gln
180 185 190
Leu Glu Met Leu Leu Pro Arg His Ser Thr Tyr His Ile Asp Asp Met
195 200 205
Arg Leu Ser Ser Asp Gly Lys Gln Ile Ile Ile Thr Ala Thr Met Met
210 215 220
Gly Thr Ala Thr Asn Pro Lys Glu Phe Val Met Asn Pro Ala Asn Ala
225 230 235 240
Gln Gly Arg His Thr Pro Gly Thr Arg Leu
245 250
Physical Characteristics
Molecular Weight 27574.42 Daltons 248 Amino Acids 33 Strongly Basic(+) Amino Acids (K,R) 21 Strongly Acidic(−) Amino Acids (D,E) 76 Hydrophobic Amino Acids (A, I, L, F, W, V) 80 Polar Amino Acids (N, C, Q, S, T, Y) 9.636 Isoelectric Point 12.379 Charge at PH 7.0
EXAMPLE 16
Sequence for C3-07
Subcloning and Sequences for C3APLT in pET
C3 has been reported to be stably expressed in E. coli by both pGEX-series and pET-series vectors (e.g., Dillon and Feig, 1995 Meth. Enzymol. 256: 174-184. Small GTPases and Their Regulators. Part B. Rho Family. W. E. Balch, C. J. Der, and A. Hall, eds.; Lehmann et al., 1999 supra; Han et al., 2001. J. Mol. Biol. 395: 95-107). The fusion proteins were expressed well in the pGEX vector, for synthesis and testing. However, for large-scale production it is more efficient to synthesize recombinant proteins without an affinity tag that increases the size of the protein produced. Also, it is more economical to synthesize proteins in large scale by affinity chromatography using automated FPLC systems. The polymerase chain reaction was used to transfer recombinant construct C3APLT into the pET T7 polymerase based system E. coli expression system (reviewed by Studier et al., 1990. Meth. Enzymol. 185: 60-89. Gene Expression Technology. D. V. Goeddel, ed.). A similar PCR approach is suitable for others in the fusion protein series of C3-based constructs with transport sequences. The pET3a vector DNA was obtained from Dr. Jerry Pelletier, McGill University. PCR primers were obtained from Invitrogen. The upper (5′) primer was 5′-GGA TCT GGT TCC GCG TCA TAT GTC TAG AGT CGA CCT G-3 (37 b) (SEQ ID NO.:38). Underlined is the Nde I site that was introduced into the primer to replace the BamHI site in pGEX4T-C3APLT. The lower primer was 5′-CGC GGA TCC ATT AGT TCT CCT TCT TCC ACT TC-3′ (32 b) (SEQ ID NO.:39). This primer introduced two changes in the coding strand DNA of pGEX4T-C3APLT, replacing the EcoRI site from pGEX4T-C3APLT with a BamH I site (underlined) and replacing a TGA stop codon with the strong stop sequence TAAT (the italicized ATTA sequence in the complementary primer). Compared to pGEX4T-C3APLT, the predicted N-terminal sequence of pET3a-C3APLT is Met-Ser rather than Gly-Ser-Ser, a loss of one serine and a substitution of Met for Gly. There were no changes in amino acid sequence at the C-terminus of C3APLT.
The target C3APLT gene was amplified using Pfu polymerase (Invitrogen/Canadian Life Technologies) with buffer, DNA and deoxyribonucleotide concentrations recommended by the manufacturer. The PCR was carried out as follows: 95° C. for 5 minutes, 10 cycles of 94° C. for 2 minutes followed by 56° C. for 2 minutes then extension at 70° C. for 2 minutes, then 30 cycles of 94° C. for 2 minutes followed by 70° C. Completed reactions were stored at 4° C. The QIAEXII kit (Qiagen) was used to purify the agarose gel slice containing DNA band. The purified PCR product DNA and the vector were digested with BamH I and Nde I (both obtained from New England BioLabs) following the instructions of the manufacturer. The digestion products were separated from extraneous DNA by agarose gel electrophoresis and purified with the QIAEXII kit. The insert and vector DNA were incubated together overnight at 16° C. with T4 DNA ligase according to directions provided by the manufacturer (New England BioLabs). Competent E. coli (DH5.alpha., obtained from Invitrogen/Canadian Life Technologies) were transformed with the ligation mixture.
DNA was prepared from purified colonies using the Qiagen plasmid midi kit, and the entire insert and junction sequences were verified by double strand sequencing of the full length of the clone (BioS&T, Montreal, Quebec) with forward primer 5′ AAA TTA ATA CGA CTC ACT ATA GGG 3′ (24 bases) (SEQ ID NO.: 40) and reverse T7 terminator sequencing primer 5′ GCT AGT TAT TGC TCAGCG G 3′ (19 bases) (SEQ ID NO.: 41). The sequence of the C3APLT cDNA in pET is given in SEQ ID NO.: 42. The amino acid sequence is given in SEQ. ID NO.: 43.
EXAMPLE 17
Modifications of Sequences
Any of sequences given in Examples 1, 2, 8, 9, 10, 11, 12 and 13, 15 and 16 could be modified to retain C3 enzymatic activity and effective transport sequences. For example amino acids encoded from DNA at the 3′ end of the sequence that represents the translation of the restriction sites used in cloning may be removed without affecting activity. Some of the amino terminal amino acids may also be removed without affecting activity. The minimal amount of sequence needed for biological activity of the C3 portion of the fusion protein is not known but could be easily determined by known techniques. For example, increasingly more of the 5′ end of the cDNA encoding C3 could be removed, and the resulting proteins made and tested for biological activity. Similarly, increasing amounts of the 3′ end could be removed and the fragments tested for biological activity. Next, fragments testing the central region could be tested for retention of C3 activity. Therefore, the C3 portion of the protein could be truncated to include just the amino acids needed for activity. Alternatively mutations could be made in the coding regions of C3, and the resulting proteins tested for activity. The transport sequences could be modified to add or remove one or more amino acids or to completely change the transport peptide, but retain the transport characteristics in terms of effective dose compared to C3 in our tissue culture bioassay (Example 4). New transport sequences could be tested for biological activity to improve the efficiency of C3 activity by plating neurons and testing them on inhibitory substrates, as described in Example 4.
As discussed previously, it has been determined in tissue culture studies, that the minimum amount of C3 that can be used to induce growth on inhibitory substrates is 25 ug/ml (Lehmann, et al. (1999) J. Neurosci. 19: 7537-7547; Morii, N and Narumiya, S. (1995) Methods in Enzymology, Vol 256 part B, pg. 196-206. If the cells are not triturated, even this dose is ineffective ( FIG. 1 ). In the context of the present invention it has been determined, for example, that at least 40 □g (40 microgram) of C3/20 g mouse needs to be applied to injured mouse spinal cord or rat optic nerve (McKerracher, Canadian patent application No.: 2,325,842). Calculating doses that would be required to treat an adult human on an equivalent dose per weight scale up used for rat and mice experiments, it would be necessary to apply 120 mg/kg of C3 (i.e. alone) to the injured human spinal cord. This large amount of recombinant C3 protein needed, creates significant problems for manufacturing, due to the large-scale protein purification and cost. It also limits the dose ranging that can be tested because of the large amount of protein needed for minimal effective doses.
Fusion proteins of the present invention are much more effective than C3 (i.e., alone) in promoting neurite outgrowth on myelin substrate. For example, concentrations of C3APLT and C3APS, 10,000 and 1,000 times less than the concentration needed for C3 may be used with comparable (similar) effects without exhibiting toxic effects (e.g., on PC-12 cells). C3-TL and C3-TS are also able to promote neurite growth on myelin substrates at doses significantly less than C3. In vivo results also indicate that lower dose of the fusion proteins may be required to promote regeneration and functional recovery after spinal cord injury in mice. Thus, fusion proteins of the present invention represent a significant improvement and advantage over C3 in both manufacture cost and doses required for treatment.
EXAMPLE 18
General Method for Determination of Inhibition of Angiogenesis
The formation of new blood vessels can be studied in a cell culture model by growing endothelial cells in the presence of a matrix of basement membrane (Matigel). Human umbilical vein endothelial cells (HUVEC) are harvested from stock cultures by trypinization, and are resuspended in growth medial consisting of EBM-2 (Clonetics), FBS, hydrocortisone, hFGF, VEGF, R3-IGF-1, ascorbic acid, hEGF, GA-1000, heparin. Matrigel (12.5 mg/mL) is thawed at 4° C., and 50 mL of Matrigel is added to each well of a 96 well plate, and allowed to solidify for 10 min. at 37° C. Cells in growth medium at a concentration of 15,000 cells/well are added to each well, and are allowed to adhere for 6 hours. A fusion protein of this invention, e.g., C3APLT, in phosphate buffered saline (PBS) is added to the well at about 10 mg/ml, and in other wells PBS is added as control. The cultures are allowed to grow for a further 6 to 8 hours. The growth of tubes can be visualized by microscopy at a magnification of 50×, and the mean length of the capillary network is quantified using Northern Eclipse software. Treatment of the cells in the Matrigel assay with a fusion protein of this invention (e.g., C3APLT) reduces tube formation (see FIG. 13 ).
EXAMPLE 19
A Lyophilized Formulation
A solution comprising a unit dosage amount of a composition of this invention comprising a fusion protein such as C3APLT dissolved in an pharmaceutically acceptable isotonic aqueous medium comprising a pharmaceutically acceptable buffer salt and/or a readily water-soluble pharmaceutically acceptable carbohydrate (preferably a pharmaceutically acceptable non-reducting sugar or a cyclodextrin) is sterile-filtered (e.g. through a 0.2 micron filter) under aseptic conditions, the filtrate is placed in a sterilized vial, the filtrate is frozen, the frozen aqueous solution is lyophilized aseptically at reduced pressure in a pharmaceutically acceptable lyophilizer to leave a dried matrix comprising the fusion protein in the vial, the vial is returned to atmospheric pressure under a sterile inert atmosphere, the vial is sealed with a sterile stopper (e.g. together with a crimp cap). The sealed vial is labeled with its contents and dosage amount and placed in a kit together with a second sealed sterile vial which contains sterilized water for injection in an amount useful to transfer into the first vial containing the lyophilized fusion protein in order to reconstitute the fusion protein matrix to a solution as a unit dosage form. In another embodiment, the fusion protein can be dissolved in a starting volume of aqueous medium which comprises a hypertonic aqueous medium, the solution sterile filtered, the filtrate filled into a vial, and lyophilized to form a dried matrix. This dried matrix can be dissolved or reconstituted in a larger-than-original volume of sterile water, the larger volume sufficient to form an isotonic solution for injection such as by intravenous injection and/or infusion. Alternatively, a hypertonic solution can be used for administration by infusion into a drip bag containing a larger volume of isotonic aqueous medium such that the hypertonic solution is substantially diluted. Optionally, a vial containing a volume of sterile water in an amount suitable to reconstitute the matrix to a unit dosage form is distributed as a kit with the lyophilized protein. Preferably the reconstituted composition comprises an isotonic solution. The fusion protein can be used for intravenous delivery, and/or infusion, and/or direct injection into tissue of the eye or tissue proximal to the eye with this formulation.
EXAMPLE 20
Construction of an Inactive Mutant Variant of C3-07, C3-07Q189A
C3-07 is a derivative of C3APLT lacking the GST sequence. C3-07 was prepared by polymerase chain reaction and subcloned into pET9a vector to create C3-07. C3-07 differs from C3-05 by silent amino acid changes which can be described as a deletion of the terminal glycine in C3-05 which provides a truncated fragment of C3-05 terminating in a serine plus a mutation (i.e., substitution) of that terminal serine in the truncated fragment by a methione to provide C3-07. C3-07Q189A was made by intentionally producing a mutation in C3-07 near the ADP-ribosyl transferase catalytic site in the fusion protein, thereby substantially reducing ADP-ribosylation activity. Two oligonucleotides were designed to change the amino acid 189 glutamine at the active site (gln, Q, coded by CAA) to 189 alanine (ala, A, coded by GCA) by site-directed-mutagenesis using the QuikChange (Stratagene). Polymerase chain reaction was carried out in a thermo cycler using 50 ng of “pET9a-BA-207” which is sometimes also referred to as “pET9a-BA05”, 133 ng of 41-mer mutant primer ZSM3, and 137 ng of 41-mer mutant primer ZSM4. The cycle program for the Q189A mutant was as follows: 95° C. for 30 sec, 18 cycles of 95° C. for 30 sec., 55° C. for 1 min., and 68° C. for 10 min., and hold at 4° C.
Primer ZSM3
5′- GCT TTT GCA GGA { GC }A CTT GAA ATG TTG CTT CCT
AGA CAT AG′
Primer ZSM4
5′- CT ATG T CT A GG AAG CAA CAT TTC AAG T{ GC } TCC
TGC AAA AGC -3′
The bracketed bold letters in the above sequence denote the change from the C3-07 sequence.
The amino acid sequence of C3-07 is SEQ ID NO.: 43.
The cDNA sequence of C3-07 is SEQ ID NO.: 42.
DpnI digestion was done according to the manufacturer's instructions and 1 μL of this product was used to transform XL1-Blue competent cells. These plates were then incubated overnight at 37° C. Clones of Putative C3-07Q189A were selected and their plasmid DNA amplified and purified using the Qiagen Midi Kit. The purified plasmids were analyzed by restriction digestion analyses. The DNA from three candidate clones was sequenced at BioS&T (Lachine, Quebec) using the T7 and T7T primers. Mutant ZSMT2-2 was confirmed to contain the mutation and the DNA was used to transform BL21 (DE3) cells and prepare a research cell bank (RCB).
Purified C3-07Q189A was prepared from E. coli . First, a flask of 0.5 L Luria Broth with glucose was inoculated with 2 vials of research cell bank (RCB) of pET9a-C3-07Q189A and grown overnight. The starter culture was diluted 10-fold into 8 flasks each containing 500 mL growth medium. The flasks were incubated at 37° C. and after 1 hour 20 min, isopropylthio-B-D-galactoside (IPTG) was added to increase the expression of C3-07Q189A. After a further 4 hours, the cells were harvested by centrifugation and stored at −80° C. until required. A sample of the harvested culture was analyzed for C3-07Q189A content. Next, the cells were thawed and subjected to primary recovery, which in the research scale process for production of C3-07 is sonication in extraction buffer. The crude extract was treated with positively-charged polymer to remove nucleic acids and with ammonium sulfate to remove some proteins and reduce the volume. Excess salt was removed. The protein was further purified by passing over four chromatography columns. The final purification and isolation steps consisted of concentration of the resulting purified protein solution (ultrafiltration can be used), filtration of the protein solution (e.g., through a 0.2 micrometer filtration membrane which can be useful to sterilize the protein solution), dispensing of the solution into sterile tubes, freezing the protein solution, and lyophilization of the frozen solution to leaving the protein formulated in the form of a powder. After the C3-07Q189A was purified, the fusion protein was analyzed to determine the amount of protein which was produced, its purity, its potency and its biological activity (e.g., ADP-ribosyl transferase related activity for neurite outgrowth). Purity was measured by scanning densitometry of SDS-polyacrylamide gels stained with Coomassie Blue. The activity of C3-07Q189A was determined using an NG108 cell 4 hour neurite outgrowth bioassay. The procedure for the bioassay comprises incubation of h NG-108 cells for 4 hours with an aliquot of a buffered solution containing C3-07Q189A. A simultaneous and otherwise identical bioassay was run as a positive control, wherein C3APLT or C3-07 was used in place of C3-07Q189A. The cells were then fixed with paraformaldehyde, stained with cresyl violet, and the percentage of cells in each well that demonstrated neurites greater than one cell body in length was determined by counting under the microscope. Each data point was determined in triplicate.
The amino acid sequence of C3-07Q189A is as follows:
Protein sequence for C3-07Q189A
(SEQ ID NO:55)
Met Ser Arg Val Asp Leu Gln Ala Cys Asn Ala Tyr
1 5 10
Ser Ile Asn Gln Lys Ala Tyr Ser Asn Thr Tyr Gln
15 20
Glu Phe Thr Asn Ile Asp Gln Ala Lys Ala Trp Gly
25 30 35
Asn Ala Gln Tyr Lys Lys Tyr Gly Leu Ser Lys Ser
40 45
Glu Lys Glu Ala Ile Val Ser Tyr Thr Lys Ser Ala
50 55 60
Ser Glu Ile Asn Gly Lys Leu Arg Gln Asn Lys Gly
65 70
Val Ile Asn Gly Phe Pro Ser Asn Leu Ile Lys Gln
75 80
Val Glu Leu Leu Asp Lys Ser Phe Asn Lys Met Lys
85 90 95
Thr Pro Glu Asn Ile Met Leu Phe Arg Gly Asp Asp
100 105
Pro Ala Tyr Leu Gly Thr Glu Phe Gln Asn Thr Leu
110 115 120
Leu Asn Ser Asn Gly Thr Ile Asn Lys Thr Ala Phe
125 130
Glu Lys Ala Lys Ala Lys Phe Leu Asn Lys Asp Arg
135 140
Leu Glu Tyr Gly Tyr Ile Ser Thr Ser Leu Met Asn
145 150 155
Val Ser Gln Phe Ala Gly Arg Pro Ile Ile Thr Gln
160 165
Phe Lys Val Ala Lys Gly Ser Lys Ala Gly Tyr Ile
170 175 180
Asp Pro Ile Ser Ala Phe Gln Gly Ala Leu Glu Met
185 190
Leu Leu Pro Arg His Ser Thr Tyr His Ile Asp Asp
195 200
Met Arg Leu Ser Ser Asp Gly Lys Gln Ile Ile Ile
205 210 215
Thr Ala Thr Met Met Gly Thr Ala Ile Asn Pro Lys
220 225
Glu Phe Val Met Asn Pro Ala Asn Ala Gln Gly Arg
230 235 240
His Thr Pro Gly Thr Arg Leu
245
The cDNA sequence of C3-07Q189A is as follows:
cDNA sequence for C3-07Q189A
(SEQ ID NO:54)
atgtctagag tcgacctgca ggcatgcaat gcttattcca ttaatcaaaa ggcttattca
60
aatacttacc aggagtttac taatattgat caagcaaaag cttggggtaa tgctcagtat
120
aaaaagtatg gactaagcaa atcagaaaaa gaagctatag tatcatatac taaaagcgct
180
agtgaaataa atggaaagct aagacaaaat aagggagtta tcaatggatt tccttcaaat
240
ttaataaaac aagttgaact tttagataaa tcttttaata aaatgaagac ccctgaaaat
300
attatgttat ttagaggcga cgaccctgct tatttaggaa cagaatttca aaacactctt
360
cttaattcaa atggtacaat taataaaacg gcttttgaaa aggctaaagc taagttttta
420
aataaagata gacttgaata tggatatatt agtacttcat taatgaatgt ttctcaattt
480
gcaggaagac caattattac aaaatttaaa gtagcaaaag gctcaaaggc aggatatatt
540
gaccctatta gtgcttttgc aggagcactt gaaatgttgc ttcctagaca tagtacttat
600
catatagacg atatgagatt gtcttctgat ggtaaacaaa taataattac agcaacaatg
660
atgggcacag ctatcaatcc taaagaattc gtgatgaatc ccgcaaacgc gcaaggcaga
720
catacacccg gtaccagact ctag
744
EXAMPLE 21
General Procedure to Determine the Relative Neuroprotection Ability in the Retina of a Fusion Protein of this Invention
C3-APLT and C3-07 are examples of fusion proteins of this invention, each protein having ADP-riboysyl transferase activity and each having an ADP-riboysyl transferase active site.
In the visual system, retinal ganglion cells die after optic nerve injury. The severity (i.e., the number of cells which die) and rate of cell death depends on the proximity of axonal injury to the eye. To study the effects of inactivation of Rho on RGC survival we have made use of two cell-membrane penetrating (i.e., cell-membrane permeable) derivatives of C3 transferase: C3-APLT and C3-07.
Rats were anaesthetised under 2-3% isoflurane. RGCs were retrogradely labelled from the superior colliculus with Fluorogold (Fluorchrome Inc, Denver, Colo.). The right midbrain of a rat was exposed by making a small circular opening in the bone, followed by aspiration of cortex, and removal of the pia matter overlying the superior colliculi. A small piece of Gelfoam soaked in an aqueous medium comprising 2% fluorgold and 10% DMSO was applied to the surface of the right superior colliculus. Seven days after Fluorogold application, the left optic nerve was transected 1 mm from the eye. The optic nerve was accessed within the orbit by making an incision parasagitally in the skin covering the superior rim of the orbit bone, taking care to leave the supraorbital vein intact. Following partial resection or reflection of the lacrimal gland, the superior extraocular muscles were spread with a small retractor or 6-0 silk suture. The optic nerve was exposed, and the surrounding sheath was cut longitudinally to avoid cutting blood vessels while exposing the optic nerve. The pia mater of the optic nerve was nicked, the optic nerve moved gently to dislodge it, and then scissors were slipped tangentially under the optic nerve to give a clean cut 1 mm from the eye. In animals used for studies on cytokine levels, a microcrush lesion was used. For these studies the pia was left intact, and the optic nerve was lifted out from the sheath and crushed 1 mm from the globe by constriction with a 10.0 suture held for 60 seconds.
Anesthetised animals received single injections of C3APLT or C3-07 in aqueous buffer immediately after the optic nerve was cut, or 4 days later. Intraocular injections were made with a 10 μl syringe attached to a glass micropipette. A hole was made in the superior nasal retina approximately 4 mm from the optic disc with a 30 g needle before introduction of the glass pipette to inject 5 μl of fusion protein (e.g., C3-07) or buffer control. The needle was withdrawn slowly to allow diffusion of the solution into the vitreous spaces. The sclera was then sealed with tissue adhesive (Indermil, Tyco Heathcare, Mansfield, USA). Care was taken not to damage the lens during injection to avoid cataract formation and consequential increased survival of the RGCs. The skin was closed, and the integrity of the retinal vasculature was evaluated by a postoperative opthalmoscopic examination. Rats with compromised vasculature or rats that developed cataracts were not included in the experimental results.
Fluorogold labeled retinas were prepared for counting 7 or 14 days after axotomy. Animals were perfused with 4% paraformaldehyde (PFA), and their eyes were removed and postfixed in 4% PFA after puncture of the cornea. The eyes were then rinsed with phosphate buffered saline (PBS) for 1 hour. Incisions were made in each eye in the four retinal quadrants, and the retinas were removed and flat-mounted on glass slides. Excess vitreous was blotted away with paper wicks. Coverslips were placed on the slides over the mounted retinas, and RGCs were examined with an ultraviolet filter (365/420). Labeled RGCs were counted under the microscope at 20× magnification with the aid of a rectangle insert in one ocular field of view of the microscope to provide a rectangular field area of 0.375 mm×0.1125 mm. Four standard rectangular areas of retina were counted at 1 and 2 mm from the disc. The number of labeled cells in each area was divided by 0.04125 (rectangular area counted in mm 2 ), and the average density for each retina was calculated as RGCs/mm 2 . Cells counts were conducted by the same investigator blind to the treatment. After axotomy, Fluorogold is also present in endothelial cells and microglial cells. These cells, identified by morphology were excluded from the counts of RGCs. Statistics were performed with Excel, and results from treated animals were compared with results from controls by T-test.
A single injection of FPLC-purified C3APLT was neuroprotective and rescued all RGCs at 7 days after axotomy, and a single injection of FPLC-purified C3-07 was neuroprotective and rescued all RGCs at 7 days after axotomy. To determine if RGC cell survival following C3-07 injection might be increased because of properties of C3-07 other than its Rho ribosylation activity, we tested the effect of C3-07Q189A on RGC cell survival. The mutant protein, C3-07Q189A, was purified by FPLC, and 1 ug was injected immediately after axotomy in the manner used for C3-07. Cell survival following administration of C3-07Q189A was not significantly different from cell survival following axotomy alone, and was significantly different from the effect of C3-07 ( FIG. 14 ). Therefore, the neuroprotective activity of C3-07 is due to the presence of ADP-ribosyl transferase in the fusion protein and thus inactivation of Rho, not from other effects.
Ischemia can be produced in the retina of the albino Lewis rat by raising intraocular pressure by intraocular injection of saline (Unoki and LaVail, Invest Opthalmol Vis. Sci. 35:907, 1994). The survival of RGCs can be assessed by counting RGCs retrogradely labeled with Florogold in retinal wholemounts, as described above.
EXAMPLE 22
Procedure to Measure Efficacy to Prevent Photoreceptor Cell Death in Rat Models of Photoreceptor Degeneration
The rescue of photoreceptor cells can be demonstrated in Royal College of Surgeons (RCS) rats, which rats have an inherited retinal degeneration (Faktorovich et al., Nature 347:83, 1990). Intraocular injections of C3APLT in aqueous buffer are made with a 10 μl syringe attached to a glass micropipette. A hole is made in the superior nasal retina approximately 4 mm from the optic disc using a 30 g needle before introduction of the glass pipette to inject 5 μl of 1 ug C3-APLT or buffer control. The needle is withdrawn slowly to allow diffusion of the solution into the vitreous spaces, and the sclera is sealed with tissue adhesive. Care is taken not to damage the lens during injection because lens damage can lead to cataract formation and consequent increases in survival of the RGCs. The skin is closed, and the integrity of the retinal vasculature is evaluated by a postoperative opthalmoscopic examination. Rats with compromised vasculature or rats that develop cataracts are not included in the experimental results.
A histological analysis useful to assess photoreceptor survival in therapeutically treated or untreated RCS rats comprises the steps of vascular perfusion of an anesthetized animal, embedding of the animal's eye in paraffin, and staining of 6 micron thick sections with hemotoxyline and eosin or with toluidine blue. In the eyes of untreated RCS rats at 53 days after birth (P53) the outer nuclear layer, which contains the photoreceptor cells, is reduced in thickness to only a few rows of cells (approximately 20% of the thickness found in normal rats at the same age). A therapeutically effective dose of C3APLT administered by intravitreal administration (e.g., a single injection comprising one microgram of protein) can restore the thickness of the outer nuclear layer, and hence rescue photoreceptor cells.
Alternatively, rescue of photoreceptor cells can be demonstrated using 2-to-3 month old male Sprague-Dawley rats in a model of exposure to constant light (115-200 foot-candles) for 1 week following the procedures of LaVail et al., PNAS USA 89:11249, 1992, the disclosure of which is incorporated herein by reference. An aqueous buffer solution of C3APLT can be injected (1 ug of protein) into the subretinal space or into the vitreous humor 48 hours prior to the onset of continuous illumination. Histological examination and analysis of retinas following a fixed recovery period (usually 10 days) is used to assess the death or damage to and the rescue or survival of photoreceptor cells.
Retinal detachment also leads to the death of photoreceptor cells. An animal model described by Erickson et al., J Struct. Biol. 108:148, 1992, the disclosure of which is incorporated herein by reference, can demonstrate the effect of administration of C3APLT to enhance survival of retinal cells in vitro relative to administration of buffer control, a protein mutated to eliminate ADP-ribosylation activity, and to untreated controls.
EXAMPLE 23
Procedure to Measure Efficacy of a Fusion Protein of the Invention to Prevent Photoreceptor Cell Death in Transgenic Mouse Models of Photoreceptor Degeneration
Several mouse genetic models of photoreceptor degeneration (e.g., rd-mutant of b subunit of cGMP phosphodiesterasel rds-mutant of peripherin) can be employed using the modes of administration described above to demonstrate fusion protein-related (e.g., C3APLT-related) photoreceptor cell enhanced survival effects in vivo.
Rd-mutant mice and rds-mutant mice exhibit retinal degeneration within a few weeks after birth. Following intravitreal injection of a fusion protein (e.g., C3APLT) as described above, tissues are analysed by histological methods described above.
Retinal explants from rd-mutant mice cultured in a C3APLT-containing medium can be assayed for thickness of the outer nuclear layer using methods described in Caffe et al., Curr. Eye Res. 12:719, 1993, the disclosure of which is hereby incorporated by reference. Thus, mouse pups are enucleated 48 hours after birth and treated with proteinase K. After this enzyme treatment, the neural retina with the retinal pigmented epithelium (RPE) attached is recovered, placed into a multi-well culture dish, and incubated in 1.2 ml culture medium (e.g., R16) for up to 4 weeks at 37° C. with 5% CO2. Immunocytochemical staining for opsin of fixed (e.g., 4% paraformaldehyde) sections is used to assess the degeneration and rescue of photoreceptor cells. In the rd-mutant mouse the outer nuclear layer (photoreceptor cells) degenerate after 2-to-4 weeks in culture. The media can be supplemented with a dose range of C3APLT to achieve an effect on retinal cell function, such as rescue of the outer nuclear layer from degeneration. Survival effects can also be shown using the TUNEL method on sections of retina analysed in the models described above.
EXAMPLE 24
Procedure to Determine Efficacy of a Fusion Protein to Prevent Neovascularization of the Retina
Uncontrolled retinal angiogenesis can contribute to the pathology of a number of diseases of the retina such as wet macular degeneration, retinitis pigmentosa, Stargardt's Disease, diabetic retinopathy, hypertensive retinopathy, and occlusive retinopathy. Vascular endothelial growth factor (VEGF) production is increased by hypoxia in the retina, and neovascularization of the retina is thereby induced.
A mouse model of ischemia-induced retinal neovascularization employs newborn C57BL/6J mice which are exposed to 75% O2 from postnatal day (P) 7 to P12, along with their nursing mothers, followed by a return to room air. To accomplish this, the mice are weighed and placed at day P7 in a plexiglass box which serves as an oxygen chamber together with enough food and water for 5 days to P12. An oxygen flow rate of 1.5 L/min is maintained through the box for 5 days. The flow rate is checked twice daily with a Beckman oxygen analyzer (model D2, Irvine Calif.). The chamber is not opened during the 5 days of hyperoxia. An intraocular injection of a fusion protein (e.g., C3APLT) is performed at day P12 and the mice are removed to ambient air thereby inducing hypoxia. At day P17 the mice are sacrificed by cardiac perfusion with saline followed by 4% paraformaldehyde (PF), and their eyes are removed and fixed in PF overnight. The eyes are then rinsed, brought through a graded alcohol series, and then radial sections 6 um thick are cut. Sections through the optic nerve head are stained with periodic acid/Schiff reagent and hematoxylin. Sections 30 um apart are evaluated for a span of 300 um through the retina. All retinal vascular nuclei anterior to the internal limiting membrane are counted in each section. The mean of 10 counted sections is determined to give the average number of neovascular nuclei per section per eye. No vascular cell nuclei anterior to the limiting membrane are observed in normal, unmanipulated animals. The administration of a fusion protein substantially reduces the number of retinal vascular nuclei relative to the number observed in the absence of fusion protein. | The Rho family of GTPases regulates axon growth and regeneration. Inactivation of Rho with C3, a toxin from Clostridium botulinum , can stimulate regeneration and sprouting of injured axons. The present invention provides novel chimeric C3-like Rho antagonists. These new antagonists are a significant improvement over C3 compounds because they are 3-4 orders of magnitude more potent to stimulate axon growth on inhibitory substrates than recombinant C3. The invention further provides methods of treating a disease of the eye by administering the compounds of the invention. | 0 |
This is a continuation of Ser. No. 07/966,938 filed Oct. 27, 1992, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a method for making a fluid bed furnace having an external circulating system for use in various facilities used for purposes such as incinerating or burning, drying or vaporization, or heat decomposition.
2. Prior Art
A fluid bed furnace having an external circulation system (called as "a fluid bed type furnace" hereafter) comprises a riser or a heating vessel of a cylindrical shape in which a fluid bed is formed by installing solid particles therein as heat transporting material, for heating material thereby for the purpose of burning, drying, vaporizing or decompositing the material. The heat transporting material are drawn out from an outlet pipe equipped at the top of the riser, and sent to a cyclone separator equipped at the end of the outlet pipe to be returned the lower portion of the riser by way of a downcomer. In this type of furnace, a smooth operation can be done such as heating of materials, reaction between materials, or drafting of the products by circulating the heat transporting material as described above.
However, the fluid bed furnace has a common problem to be solved in general in obtaining a smooth circulation of the heat transporting material as well as in controlling the quantity thereof. It is essential to obtain a smooth circulation of the heat transporting material for realization of the quantity control thereof. This realization of smooth circulation of solid particles mostly depends on the design of the downcomer. Namely, it is important to correctly select the height level of an end connection which opens at the lower part of a riser, and then it is important to determine the size of the downcomer in relation to the selected height level.
In the conventional technology, such determination of height level of the end connection and determination of the size of the downcomer were performed under totally different ideas from each other. That is, the former is determined from the total amount of the heat transporting material installed in the furnace, and the latter is determined from the calculated amount of heat transporting material circulating in the furnace. Whether the height level of an end connection is proper or not is judged from density of heat transporting material at a determined location when stirring the heat transporting material in the riser. However, since the density of heat transporting material at the location alters according to the parameters such as grain size or specific gravity of the heat transporting material, or velocity of the gas in the riser, it is impossible to evaluate the height level univocally according to the density of heat transporting material. That is, the pressure or quantity of pressure drop at the present location can be used for the justification of the height level of an end connection.
On the other hand, the judgment of the size of the downcomer is done according to the velocity of the heat transporting material in the downcomer as well as above mentioned calculated amount of the heat transporting material in circulation. Since these values also alter according to the parameters such as grain size or specific gravity of the heat transporting material, the optimization of the operation includes much difficulty.
In the conventional technology, in order to avoid such intricacy, a pooling device is provided at the middle of the downcomer for pooling the heat transporting material therein, to which a means for blowing compressed gas into the pooling device for sending the heat transporting material into the riser. By this method, it is necessary to put gas energy at an exalted state since the gas is blown into the furnace to raise the velocity of the heat transporting material which at first is zero or very small. It is also necessary by this method to distend the size of the downcomer since the total volume of flow increases due to the gas blow.
As described above, in the conventional method of making the fluid bed type furnace, there are some difficulties as follows. In determining the height of the connecting end from the total amount of the heat transporting material, or in determining the size of the downcomer from the calculated amount of heat transporting material in circulation, it is difficult to obtain correct values since these values cannot be determined univacally as described above. Thus, in the furnace designed after the conventional process, many problems will occur relating to the downcomer, such as blocking of the heat transporting material when the size of the downcomer is small, or decrease of the heat transporting material in circulation due to the generation of gas flow in a direction from the lower part of the riser to a cyclone separator by way of the downcomer (called as a "reverse gas flow" hereafter) when the size of the downcomer is large.
Otherwise, in the method of equipping a pooling device at the middle of the downcomer, not only is the size of the downcomer necessarily large due to increase of volume of flow occurring from the gas blow, but also a large energy is necessary for returning the heat transporting material by bringing them at high speed from stationary state or a state of very low speed.
SUMMARY OF THE INVENTION
The present invention was made in view of the above background, and is aimed at presenting a method for making a fluid bed type furnace having an external circulation system, in which generation of blocking of the heat transporting material or reverse gas flow can be prevented by properly selecting the size of the downcomer or so in accordance with required amount of heat transporting material in circulation or characteristics of material charged to the furnace.
The present invention is to accomplish the objectives mentioned above, and thus presents a method for making a fluid bed type furnace comprising a riser for containing a mixture of primary air and solid heat transport medium, a cyclone for separating said solid heat transport medium from gas, and a down comer disposed outside of the riser for returning said solid heat transport medium from said cyclone to said riser, the method comprising the step of determining the diameter of the down comer and the diameter of the riser so that the ratio (X) thereof falls in an area between two lines described as follows, in a Ws-X plane:
Ws=12500X.sup.5 -12080X.sup.4 +4370X.sup.3 -600X.sup.2 +36X
and
Ws=5800X.sup.4 +1600X.sup.3 -580X.sup.2 +44X
wherein, Ws is flow rate of solid heat transport medium in the riser at each unit area the cross section (kg/m 2 sec); X is a ratio of the diameter of down comer (d) to the diameter of riser (D).
According to another aspect of the present invention there is also provided a method for making an external circulation fluid bed furnace according to, wherein the fluid bed furnace further comprises a supplemental air supply means for blowing hot air in one of said cyclone and said down comer, the method-further comprising the step of determining the diameter of the down comer so that ratio (r) of the diameter of down comer (da) and the diameter of down comer without supplemental air supply means (dO) falls in an area between first and second lines described as follows, in a r-F plane:
First line being defined as:
______________________________________r = -2.8F + 1 for 0 ≦ F < 0.1r = -0.7F + 0.79 for 0.1 ≦ F______________________________________
Second line being defined as:
______________________________________r = -3F + 0.877 0 ≦ F < 0.02r = -0.27F + 0.871 0.02 ≦ F < 0.1r = -33F + 0.663 0.1 ≦ F______________________________________
wherein r=da/d0; F=Fa/Ft; Fa is the volume of supplemental air, and Ft is the volume of total air.
Another aspect of the present invention provides a method for making an external circulation fluid bed furnace according to, wherein said down comer has an aperture opening to a lower part of said riser for returning said solid heat transporting medium, and the method comprises a step of determining the height (H) of said aperture measured from a standard level, and a ratio (L) of said height (H) to a radius (D/2) of said down comer so that the height (H) and ratio fall within the area between first and second lines as defined as follows in a y-L plane:
First line:
______________________________________y = -0.5L + 0.75 for -1.3 ≦ L < -0.715y = -0.15L + 1.0 for -0.715 ≦ L < 0y = -0.3L + 1.0 for 0 ≦ L < 0.5y = -0.05L + 0.875 for 0.5 ≦ L < 1.5______________________________________
Second line:
______________________________________y = -0.4L + 1.0 for -1.3 ≦ L < 0y = -0.05L + 1.0 for 0 ≦ L ≦ 1.5______________________________________
wherein L=H/D/2=2H/D
Still further aspect of the invention provides a method for making an external circulation fluid bed furnace according to, wherein at least one of fuel and combustible material supplied to said furnace contains alkali element, and the method comprises a step for determining the diameter of the down comer so that the diameter falls within the area between first line and second line defined as follows in an A-X plane:
First line:
A=714X.sup.3 -2256X.sup.2 +2424X-882
Second line:
A=169.7X.sup.2 -346.8X+1777.1
wherein X is a deviation of the diameter of down comer from that of standard diameter.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a schematic drawing showing an embodiment of the present invention.
FIG. 2 is a cross-sectional drawing of the riser.
FIG. 3 is a graph showing relationship between a ratio x of diameter d of the downcomer to the diameter D of the riser and the amount of solid particles in circulation Ws.
FIG. 4 is a graph showing relationship between a ratio r of diameter da of the downcomer when subsidiary air is supplied, to diameter do of the downcomer when no subsidiary air is supplied, and a ratio F of the amount of the subsidiary air to the total amount of supplied air.
FIG. 5 is a graph showing relationship between ratio of height of the end connection of the downcomer from a standard level to radius of riser and deviation y of diameter of the downcomer.
FIG. 6 is a graph showing relationship between deviation x of the diameter of the downcomer from its standard value and density A of alkari salt produced through reaction.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Embodiments of the present invention will be described with reference to FIGS. 1 through 6 and Table 1 through 4 in the following sections.
FIGS. 1 and 2 show an embodiment wherein the furnace according to the present invention is utilized to burn industrial liquid wastes and sludges.
As shown in FIGS. 1 and 2, the furnace is provided with a riser 1, a cyclone 5, an outlet conduit 2 communicating the riser to the cyclone, a down comer 4 provided underneath the cyclone. The riser 1 defines a cylindrical internal space for combustion reaction and having an inner lining made of a heat resistant material. The riser is provided with first and second primary air inlet conduits 11, 12 at a lower part thereof and at different heights. The down comer 4 has a vertical upper portion and an inclined lower portion which is connected to the lower portion of the internal space of the riser through an aperture 3a. The aperture 3a is located at a higher location compared to the secondary air inlet conduit 11 and their vertical distance is denoted by H.
Two supplementary air inlet nozzles 6, 8 are provided to cyclone 5 and outlet conduit 2 at locations closer to riser 1 and supply supplemental air to cyclone 5 and outlet conduit 2 through flow control valves 7, 9. First and second primary air inlet conduits 11, 12 supply primary and secondary air to the riser through flow control valves 13, 14.
Riser 1 is provided with a combustible material inlet port 15 and an outlet valve 18 at a middle portion and a bottom portion thereof, respectively. Cyclone 5 is provided with an outlet line 16 and an outlet port 16.
Heat transporting medium is provided in the riser when the furnace is operated and air is blown from the air inlet conduits 11, 12 for combustion and fluidization of the heat transporting medium. The combustible medium is supplied to the furnace through combustible medium inlet port 15. The total amount of the air supplied to the riser, which is a sum of the air supplied through primary air inlet conduits 11, 12 and secondary air inlet conduits 6, 8, is determined so that the oxygen enough to react all the combustible material is burned. When the air is not supplied through secondary air conduits 6, 8, the flow rate of the lower primary air inlet 12 remains constant while that of the upper primary air inlet 11 varies. The total air flow rate approximately determines the rate of flow of the heat transporting medium in the riser per unit time and per unit cross sectional area.
The heat transporting medium, which is a form of small particles, is first mixed with the primary air supplied from the primary air inlet conduits, blown in a form of a gas-solid particle mixture. The combustible material is also mixed with the air and the heat transporting material, and receives heat from therefrom consequently losing humidity contained in it. The combustible material is crushed into small pieces by the numerous collisions with the heat transporting material. The combustible material crushed into small pieces are blown upward with the heat transport medium by the circulating air as burning.
The combustible material blow upward with the heat transporting medium is accelerated by the secondary air blow through secondary air inlet conduit 11 and continues burning. The combustible material completes burning approximately when it reaches the top portion of the riser, and the leavings of the combustion, that is mainly ash, is lead to cyclone 5 through outlet conduit 2 with the heat transporting medium.
The heat transporting medium lead to the cyclone is separated from the gas mixture by the centrifugal force in the cyclone, and exited from a lower part of the cyclone to enter the down comer. The air and the combustion leavings separated from the heat transporting medium is lead to outlet conduit 16 so as to be laid outside the system described above.
In the case wherein either the combustible material or the fuel for combustion contains a compound containing potassium or sodium, a salt of these elements are formed while the combustible material is burned in the riser. Most portion of the salt formed as described above is in a form of small particles or formed on the surface of the heat transporting material. However, some portion of the salt further reacts with the heat transporting medium to produce reaction products. Such reaction products have lower melting temperatures, and tend to melt and stick to the internal surface of the system, such as inside the down comer and obstacles a smooth flow of the medium in the system. The flow condition in the system is affected seriously when such reaction products stick to the inner surface and hinders the flow depending on the dimensions of down comer 4 and inlet conduits 3.
It has been found by experiments that is supplemental air is provided by supply air conduits 6, 8 provided with flow control valve 7, 9, the hindrance due to the sticking reaction products is substantially reduced especially for small down comer sizes. When the diameter of the down comer is relatively small, the effective diameter of the down comer tends to be reduced due to the sticking reaction products. The flow rate in the down comer is consequently reduced and the separation ability of the cyclone is degraded, and the amount of the heat transport medium effective operating in the system is reduced. The operation of the system thus becomes unstable and difficult.
When the diameter of down comer 4 is larger than an appropriate size, an upward air flow occurs in the down comer from the aperture of the down comer opening to the lower part of riser 1 toward cyclone 5. Due to the upward air flow, a portion of the heat transporting medium is blown upward and exited to the outside of the system through cyclone 5 and outlet conduit 16. This upward flow can also be reduced or stopped by providing a downward stream by supplementary air through supplementary air conduits 6, 8.
A number of cold experiments have been performed without heating the medium in order to evaluate the effects of the parameters except for the effects of alkali salts. Hot experiments with heating the mediums have also been performed in order to evaluate the effects of the alkali elements contained in the combustible materials. The results of the experiments are described as follows in Tables 1 through 4.
In the experiments, diameters of the riser was selected from 0.3 m and 0.32 m, diameters of the down comer was selected from various values between 0.033 m and 0.1 m, total air supply was varied between 480 and 1720 Nm 3 /h, and supplementary air which was included in the total air supply was varied between 0 and 350 Nm 3 /h. Height of inlet conduit 3 measured from the center of secondary air inlet conduit 11 to the center of the inlet conduit 3 was varied from 0.15 to 0.525 m.
The operation of the furnace is evaluated according to the existence of congestion in down comer 4 or inlet conduit 3.
Effects of the variables on the congestion obtained from the experiments are described in FIGS. 3 to 6.
Table 1 shows the effects of the diameter d of down comer and diameter D of the riser on the upward stream in the down comer. The flow was measured in terms of the amount of solid particles flowing upwards in the down comer. In the comparison, diameter D of the riser and the height H of inlet conduit 3 measured from secondary air inlet conduit 11 are maintained unchanged, and total air circulation Ws and diameter d of down comer 4 were varied without supplying supplemental air. FIG. 3 shows the conditions wherein no congestion occurred in the down comer. FIG. 3 shows that by properly choosing the variable, it is possible to create a regular circulation of the air and heat transporting medium, that is, unidirectional flow without reversal flow in the down comer. The conditions is that the ratio of the diameter d of the down comer to the diameter D of the riser (X) falls in an area between two lines described as follows, in a Ws-X plane:
Ws=12500X.sup.5 -12080X.sup.4 +4370X.sup.3 -600X.sup.2 +36X
and
Ws=5800X.sup.4 +1600X.sup.3 -580X.sup.2 +44X
wherein, Ws is flow rate of solid heat transport medium in the riser at each unit area the cross section (kg/m 2 sec). The parameter Ws was between 0 and 50.
When X is larger than the above area, an upward stream occurs in the down comer. When X is smaller than the above area, a congestion occurs in the down comer.
It becomes possible to determine the diameter of the
TABLE 1__________________________________________________________________________ weight height dia- supple of ofdia- meter total mental circu- down-meter of air air lating comerof down- volume volume media aper- blownriser comer (Ft) (Fa) (Ws) ture amount conges F = r =(D)m (d)m Nm.sup.3 /h Nm.sup.3 /h kg/m.sup.2 · s (H) (Wc) tion X = d/D Fa/Ft L = 2H/D y = d/do da/do x__________________________________________________________________________ = d/do0.3 0.04 1200 0 4.5 0.3 1.3 X 0.133 0 2 -- -- --0.3 0.04 1300 0 5.2 0.3 1.5 X 0.133 0 2 -- -- --0.3 0.04 1350 0 5.4 0.3 -- ◯ 0.133 0 2 -- -- --0.3 0.05 1700 0 19.1 0.3 -- ◯ 0.167 0 2 -- -- --0.3 0.06 1750 0 20.0 0.3 -- ◯ 0.2 0 2 -- -- --0.3 0.06 1700 0 19.2 0.3 1.6 X 0.2 0 2 -- -- --0.3 0.07 1000 0 3.2 0.3 6.3 X 0.233 0 2 -- -- --0.3 0.07 1100 0 3.5 0.3 1.2 X 0.233 0 2 -- -- --0.3 0.07 1200 0 36 0.3 1.7 X 0.233 0 2 -- -- --0.3 0.07 2200 0 38 0.3 -- ◯ 0.233 0 2 -- -- --0.3 0.1 1500 0 9.4 0.3 8.9 X 0.333 0 2 -- -- --0.3 0.1 1560 0 9.9 0.3 1.1 X 0.333 0 2 -- -- --0.3 0.1 1700 0 19.8 0.3 1.6 X 0.333 0 2 -- -- --0.3 0.1 2200 0 49.0 0.3 1.7 X 0.333 0 2 -- -- --0.3 0.125 1750 0 18.8 0.3 5.7 X 0.417 0 2 -- -- --0.3 0.125 1850 0 20.6 0.3 1.8 X 0.417 0 2 -- -- --0.3 0.125 1950 0 26 0.3 1.5 X 0.417 0 2 -- -- --0.3 0.125 2200 0 46 0.3 1.9 X 0.417 0 2 -- -- --0.3 0.14 2000 0 35 0.3 4.9 X 0.467 0 2 -- -- --0.3 0.14 2100 0 41 0.3 1.0 X 0.467 0 2 -- -- --0.3 0.14 2300 0 50 0.3 1.3 X 0.467 0 2 -- -- --0.3 0.15 2000 0 41.5 0.3 8.9 X 0.5 0 2 -- -- --0.3 0.15 2300 0 50 0.3 7.0 X 0.5 0 2 -- -- --__________________________________________________________________________
down comer according to the conditions described in FIG. 3 as follows. First, the total amount of air circulation is determined for burning total amount of combustible material in the furnace. Then the rate of circulation of the heat transporting medium is determined. Then, according to FIG. 3, a variable X is determined, and the diameter d of the down comer is determined by using the diameter D of the riser and variable X.
Table 2 shows the data obtained from experiments wherein the diameter d of the down comer was varied around 0.06 m while maintaining the diameter D of the riser and total air circulation Ws constant. Supplemental air flow was supplied through supplemental air conduits 6, 8, and the proportion F of the supplemental air Fa to the total air flow Ft was varied. FIG. 4 shows the effects of the diameter of the down comer in terms of the deviation from its mean value, that is, 0.06 m.
The condition wherein no congestion occurs is when the ratio r of the diameter da of down comer and the diameter of down comer do without supplemental air supply means falls in an area between first and second lines described as follows, in a r-F plane:
First line being defined as:
______________________________________r = -2.8F + 1 for 0 ≦ F < 0.1r = -0.7F + 0.79 for 0.1 ≦ F______________________________________
Second line being defined as:
______________________________________r = -3F + 0.877 0 ≦ F < 0.02______________________________________
TABLE 2__________________________________________________________________________ weight height dia- supple of ofdia- meter total mental circu- down-meter of air air lating comerof down- volume volume media aper- blownriser comer (Ft) (Fa) (Ws) ture amount conges F = r =(D)m (d)m Nm.sup.3 /h Nm.sup.3 /h kg/m.sup.2 · s (H) (Wc) tion X = d/D Fa/Ft L = 2H/D y = d/do da/do x__________________________________________________________________________ = d/do0.3 0.06 1700 0 19.2 0.3 1.6 X 0.2 0 2 -- -- --0.3 0.058 1700 20 19.1 0.3 5.4 X 0.193 0.012 2 -- 0.967 --0.3 0.057 1700 20 19.4 0.3 1.2 X 0.190 0.012 2 -- 0.95 --0.3 0.052 1700 20 19.2 0.3 1.4 X 0.173 0.012 2 -- 0.867 --0.3 0.050 1700 20 19.5 0.3 -- ◯ 0.167 0.012 2 -- 0.833 --0.3 0.050 1705 35 19.4 0.3 1.6 X 0.167 0.021 2 -- 0.833 --0.3 0.048 1705 35 19.6 0.3 -- ◯ 0.160 0.021 2 -- 0.800 --0.3 0.051 1700 80 19.2 0.3 6.3 X 0.170 0.047 2 -- 0.850 --0.3 0.050 1700 80 19.0 0.3 1.1 X 0.167 0.047 2 -- 0.833 --0.3 0.042 1700 150 18.7 0.3 1.4 X 0.140 0.088 2 -- 0.700 --0.3 0.044 1720 170 19.8 0.3 5.1 X 0.147 0.099 2 -- 0.733 --0.3 0.043 1720 170 18.7 0.3 1.3 X 0.143 0.102 2 -- 0.717 --0.3 0.036 1675 175 18.9 0.3 1.5 X 0.120 0.104 2 -- 0.600 --0.3 0.035 1675 175 19.4 0.3 -- ◯ 0.117 0.104 2 -- 0.583 --0.3 0.042 1700 250 19.4 0.3 8.1 X 0.14 0.147 -- -- 0.700 --0.3 0.041 1700 250 20.1 0.3 1.9 X 0.137 0.147 -- -- 0.683 --0.3 0.038 1750 250 19.9 0.3 1.2 X 0.127 0.143 -- -- 0.633 --0.3 0.035 1700 250 19.1 0.3 1.1 X 0.117 0.147 -- -- 0.583 --0.3 0.034 1700 250 18.8 0.3 -- ◯ 0.113 0.147 -- -- 0.567 --0.3 0.040 1700 350 19.3 0.3 6.0 X 0.133 0.206 -- -- 0.667 --0.3 0.039 1700 350 18.9 0.3 1.3 X 0.130 0.206 -- -- 0.65 --0.3 0.034 1700 350 19.2 0.3 1.7 X 0.113 0.206 -- -- 0.567 --0.3 0.033 1700 350 18.6 0.3 -- ◯ 0.110 0.206 -- -- 0.550 --__________________________________________________________________________
______________________________________r = -0.27F + 0.871 0.02 ≦ F < 0.1r = -33F + 0.663 0.1 ≦ F______________________________________
wherein r=da/d0; F=Fa/Ft; Fa is the volume of supplemental air, and Ft is the volume of total air.
The figure tells that when the supplemental air supply is high, the diameter of the down comer can be small. FIG. 4 provides information how the diameter of the down comer must be modified by taking into account the supplemental air flow.
Table 3 shows the effects of the height 3a of the aperture through which the down comer is connected to the riser. The parameters H and d as described above were varied in order to obtain this information.
FIG. 5 shows the relationship between the diameter of the down comer and the height of the aperture 3a. According to FIG. 5, it is understood that the down comer must have a large diameter so that the heat transporting medium is returned to the lower part of the riser where the air-solid mixture has a relatively high density. The relationship is when the ratio (L) of said height (H) to a radius (D/2) of said down comer falls within the area between first and second lines as defined as follows in a y-L plane (wherein L=H/D/2=2H/D):
First line:
______________________________________y = -0.5L + 0.75 for -1.3 ≦ L < -0.715y = -0.15L + 1.0 for -0.715 ≦ L < 0y = -0.3L + 1.0 for 0 ≦ L < 0.5y = -0.05L + 0.875 for 0.5 ≦ L ≦ 1.5______________________________________
TABLE 3__________________________________________________________________________ weight height dia- supple of ofdia- meter total mental circu- down-meter of air air lating comerof down- volume volume media aper- blownriser comer (Ft) (Fa) (Ws) ture amount conges F = r =(D)m (d)m Nm.sup.3 /h Nm.sup.3 /h kg/m.sup.2 · s (H) (Wc) tion X = d/D Fa/Ft L = 2H/D y = d/do da/do x__________________________________________________________________________ = d/do0.3 0.085 1700 0 17.9 0.15 9.3 X 0.283 0 1.0 1.417 -- --0.3 0.083 1700 0 18.6 0.15 1.9 X 0.280 0 1.0 1.400 -- --0.3 0.077 1700 0 18.8 0.15 1.7 X 0.257 0 1.0 1.283 -- --0.3 0.075 1700 0 18.1 0.15 -- ◯ 0.250 0 1.0 1.250 -- --0.3 0.073 1700 0 18.9 0.225 7.8 X 0.243 0 1.5 1.217 -- --0.3 0.072 1700 0 19.3 0.225 2.1 X 0.240 0 1.5 1.200 -- --0.3 0.064 1700 0 19.6 0.225 1.8 X 0.213 0 1.5 1.067 -- --0.3 0.063 1700 0 19.1 0.225 -- ◯ 0.210 0 1.5 1.050 -- --0.3 0.060 1700 0 19.2 0.3 1.6 X 0.2 0 2.0 1.000 -- --0.3 0.058 1700 0 19.6 0.375 12.6 X 0.193 0 2.5 0.967 -- --0.3 0.057 1700 0 20.5 0.375 2.3 X 0.190 0 2.5 0.950 -- --0.3 0.053 1700 0 20.0 0.375 1.5 X 0.177 0 2.5 0.883 -- --0.3 0.051 1700 0 20.3 0.375 -- ◯ 0.170 0 2.5 0.850 -- --0.3 0.058 1700 0 19.1 0.45 7.3 X 0.193 0 3.0 0.967 -- --0.3 0.057 1700 0 18.6 0.45 1.8 X 0.190 0 3.0 0.950 -- --0.3 0.053 1700 0 19.4 0.45 1.4 X 0.177 0 3.0 0.883 -- --0.3 0.051 1700 0 17.9 0.45 -- ◯ 0.170 0 3.0 0.850 -- --0.3 0.056 1700 0 18.6 0.525 9.2 X 0.187 0 3.5 0.933 -- --0.3 0.054 1700 0 19.5 0.525 1.3 X 0.180 0 3.5 0.900 -- --0.3 0.050 1700 0 18.1 0.525 1.6 X 0.167 0 3.5 0.833 -- --0.3 0.048 1700 0 18.6 0.525 -- ◯ 0.160 0 3.5 0.800 -- --__________________________________________________________________________
______________________________________y = -0.4L + 1.0 for -1.3 ≦ L < 0y = -0.05L + 1.0 for 0 ≦ L ≦ 1.5______________________________________
The Figure provides a method for adjusting the diameter of the down comer for the deviations of H from its standard value that is 0.3 m.
Table 4 shows the results of the experiments which was performed at 800° C. for a combustible material containing alkali elements.
FIG. 6 shows the relationship between the concentration of alkali salts in the combustible material and the diameter of the down comer. The optimal conditions are when the diameter falls within the area between first line and second line defined as follows in an A-X plane:
First line:
A=714X.sup.3 -2256X.sup.2 +2424X-882
Second line:
A=169.7X.sup.2 -346.8X+177.1
wherein X is a deviation of the diameter of down comer from that of standard diameter. Parameter A is between 0 and 20. The parameter A is the weight ratio of Na 2 CO 3 and K 2 CO 3 derived from Na and K contained in the combustible material to the total dry weight of the combustible material. The relationship is described as follows:
A={(total weight of Na 2 CO 3 derived from Na content
TABLE 4__________________________________________________________________________ weight height density dia- supple of of ofdia- meter total mental circu- down- alkarimeter of air air lating comer saltof down- volume volume media aper- in ma- blownriser comer (Ft) (Fa) (Ws) ture terial amount conges X = F = L = r =(D)m (d)m Nm.sup.3 /h Nm.sup.3 /h kg/m.sup.2 · s (H) (A) (Wc) tion d/D Fa/Ft 2H/D y = d/do da/do x__________________________________________________________________________ = d/do0.32 0.062 480 0 5.5 0.3 0 1.4 X 0.194 0 2.0 -- -- 1.0000.32 0.062 480 0 5.2 0.3 3.6 -- ◯ 0.194 0 2.0 -- -- 1.0000.32 0.065 480 0 5.6 0.3 3.6 -- ◯ 0.203 0 2.0 -- -- 1.0480.32 0.067 480 0 5.1 0.3 3.6 1.7 X 0.209 0 2.0 -- -- 1.0810.32 0.072 480 0 5.5 0.3 3.6 1.4 X 0.225 0 2.0 -- -- 1.1610.32 0.074 480 0 5.6 0.3 3.6 7.1 X 0.231 0 2.0 -- -- 1.1940.32 0.070 480 0 5.4 0.3 7.0 -- ◯ 0.219 0 2.0 -- -- 1.1290.32 0.074 480 0 5.3 0.3 7.0 1.1 X 0.231 0 2.0 -- -- 1.1940.32 0.076 480 0 5.1 0.3 7.0 1.4 X 0.238 0 2.0 -- -- 1.2260.32 0.078 480 0 4.8 0.3 7.0 7.9 X 0.244 0 2.0 -- -- 1.2580.32 0.076 480 0 5.2 0.3 12.0 -- ◯ 0.238 0 2.0 -- -- 1.2260.32 0.078 480 0 5.6 0.3 12.0 1.6 X 0.244 0 2.0 -- -- 1.2580.32 0.080 480 0 4.6 0.3 12.0 1.2 X 0.250 0 2.0 -- -- 1.2900.32 0.082 480 0 6.0 0.3 12.0 9.9 X 0.256 0 2.0 -- -- 1.3230.32 0.076 480 0 5.6 0.3 17.0 -- ◯ 0.238 0 2.0 -- -- 1.2260.32 0.078 480 0 4.8 0.3 17.0 1.3 X 0.244 0 2.0 -- -- 1.2580.32 0.080 480 0 5.2 0.3 17.0 1.0 X 0.250 0 2.0 -- -- 1.2900.32 0.082 480 0 5.6 0.3 17.0 1.7 X 0.256 0 2.0 -- -- 1.3230.32 0.083 480 0 5.5 0.3 17.0 14.5 X 0.259 0 2.0 -- -- 1.339__________________________________________________________________________ supposing that all the Na content in the combustible material reacted to make it)+(total weight of K.sub.2 CO.sub.3 derived from K content supposing that all the K content in the combustible material reacted to make it)}/(dry weight of the combustible material)
For example, if the combustible material contains 50% by weight of water which contains 2 wt % percent Na and 0.5 wt % of K, the variable A is calculated as follows:
______________________________________A = 0.02 × (molecular weight of Na.sub.2 CO.sub.3)/2(molecularweight of Na) + 0.005 × (molecular weight ofK.sub.2 CO.sub.3)/2(molecular weight of K) =0.02 × 2.304 + 0.005 × 1.767 =0.055______________________________________
The above relationship provides the method determining the diameter of down comer when the concentration A of the alkali salt is provided. | The present invention provides a method for making an external circulation fluid bed furnace which does not require a chamber for retaining heat transporting medium communicating with the down comer. According to the method of the present invention, said chamber is eliminated by properly determining the dimension of the down comer etc. According to the present invention, the ratio of the diameter of the down comer to the diameter of the riser so that the ratio (X) thereof falls in an area between two lines described as follows, in a Ws-X plane:
Ws=12500X.sup.5 -12080X.sup.4 +4370X.sup.3 -600X.sup.2 +36X
and
Ws=5800X.sup.4 +1600X.sup.3 -580X.sup.2 +44X
wherein, Ws is flow rate of solid heat transport medium in the riser at each unit area the cross section (kg/m 2 sec); X is a ratio of the diameter of down comer (d) to the diameter of riser (D). | 5 |
TECHNICAL FIELD
[0001] The present invention relates to a method of preparing lithium transition metal phosphate, and in particular, to a method of preparing lithium transition metal phosphate, wherein the method includes: feeding reactants including lithium, a transition metal, and phosphoric acid into a reactor, mixing the reactants at a molecular level in the reactor; and generating a crystal nucleus by chemically reacting the reactants in the reactor.
BACKGROUND ART
[0002] Lithium transition metal phosphate (LiMPO 4 , where M denotes a transition metal; hereinafter referred to as LMP) is a promising cathode active material for lithium secondary batteries.
[0003] As a method of preparing LMP, for example, a solid phase method and a sol-gel method are used.
[0004] In a solid phase method, solid-phase reactants are mixed and heated to prepare LMP. However, due to the high heating temperature, it is difficult to obtain uniform nanoparticles. Also, to manufacture such uniform nanoparticles, micro-particle powder reactants are required. Accordingly, a dependency on reactants is high and thus economic efficiency reduces.
[0005] Moreover, the solid phase method involves thermal treatment in a reducing condition, which requires particular attention. Due to a low electric conductivity of LMP, to realize battery characteristics, surfaces of LMP particles need to be coated with a conductive material. However, this surface coating is difficult to be implemented with the solid phase method.
[0006] In a sol-gel method, a metal alkoxide source material is transformed into a sol state and then gelled through condensation reaction, followed by drying and heating to prepare LMP. However, reactants used in this method are expensive and also, this method is based on an organic solvent. Accordingly, manufacturing costs are high.
DETAILED DESCRIPTION OF THE INVENTION
Technical Problem
[0007] The present invention provides a method of preparing a lithium transition metal phosphate, wherein the method includes: feeding reactants including lithium, a transition metal, and phosphoric acid into a reactor, followed by mixing the reactants at a molecular level in the reactor; and generating a crystal nucleus by chemically reacting the reactants in the reactor.
Technical Solution
[0008] According to an aspect of the present invention, there is provided a method of preparing lithium transition metal phosphate, the method including: feeding reactants comprising lithium, a transition metal, and phosphoric acid into a reactor, and mixing the reactants at a molecular level in the reactor; and generating a crystal nucleus by chemically reacting the reactants in the reactor.
[0009] The transition metal may include at least one selected from the group consisting of Fe, Mn, Co, and Ni.
[0010] The chemical reaction may be an acid-base reaction.
[0011] The reactants may be fed in at least one of a solution form and a suspension form into the reactor.
[0012] The reactants may include an acidic source material and a basic source material, wherein the acidic source material may be fed into the reactor through a first source material feeding line, and the basic source material may be fed into the reactor through a second source material feeding line.
[0013] The acidic source material may include lithium, a transition metal, and phosphoric acid, and the basic source material may include an inorganic base.
[0014] The acidic source material may include a transition metal and phosphoric acid, and the basic source material may include lithium.
[0015] The acidic source material may include lithium and phosphoric acid, and the basic source material may include a transition metal.
[0016] The basic source material may include lithium and a transition metal, and the acidic source material may include phosphoric acid.
[0017] A time (T M ) taken to mix the reactant at the molecular level may be shorter than a time (T N ) taken to generate the crystal nucleus.
[0018] The time (T M ) may be in a range of 10 to 100 μs, and the time (T N ) may be 1 ms or less.
[0019] An inner temperature of the reactor may be maintained in a range of 0 to 90° C.
[0020] A molar ratio of lithium and the transition metal to the phosphoric acid ((Li+M)/phosphoric acid) in the reactants may be in a range of about 1.5 to about 2.5.
[0021] A retention time of the reactants in the reactor may be in a range of 1 ms to 10 s.
[0022] The reactor may be a high gravity rotating packed bed reactor including: a chamber that defines an inner space; a permeable packed bed that is rotatable, is disposed inside the chamber, and is filled with a porous filler; at least one source material feeding line through which the reactants are fed into the inner space; and a slurry outlet through which a slurry is discharged from the inner space.
[0023] The reaction may further include a gas outlet for discharging gas from the inner space.
[0024] The porous filler may include titanium.
[0025] A centrifugal acceleration of the permeable packed bed may be in a range of 10 to 100,000 m/s 2 .
[0026] The lithium transition metal phosphate may have an olivine type crystal structure.
Advantageous Effects
[0027] According to the embodiments of the present invention, a lithium transition metal phosphate preparation method may produce LMP with uniform particle size distribution and high purity in large quantities at low-costs, the method including feeding reactants including lithium, a transition metal, and phosphoric acid into a reactor and mixing the reactants at a molecular level in the reactor; and generating a crystal nucleus by chemically reacting the reactants in the reactor.
DESCRIPTION OF THE DRAWINGS
[0028] FIG. 1 is a schematic cross-sectional view of a high gravity rotating packed bed reactor that is used in a method of preparing a lithium transition metal phosphate according to an embodiment of the present invention.
[0029] FIG. 2 shows a transmission electron microscope (TEM) image of lithium transition metal phosphate nanoparticles prepared according to Example 1.
[0030] FIG. 3 illustrates an X-ray diffraction (XRD) pattern of the lithium transition metal phosphate nanoparticles prepared according to Example 1.
[0031] FIG. 4 is a TEM image of lithium transition metal phosphate nanoparticles prepared according to Example 2.
[0032] FIG. 5 illustrates an X-ray diffraction pattern of lithium transition metal phosphate nanoparticles prepared according to Example 2.
[0033] FIG. 6 is a TEM image of lithium transition metal phosphate nanoparticles prepared according to Example 3.
[0034] FIG. 7 illustrates an X-ray diffraction pattern of lithium transition metal phosphate nanoparticles prepared according to Example 3.
[0035] FIG. 8 shows a TEM image of lithium transition metal phosphate nanoparticles prepared according to Example 4.
[0036] FIG. 9 illustrates an X-ray diffraction pattern of lithium transition metal phosphate nanoparticles prepared according to Example 4.
BEST MODE
[0037] Hereinafter, methods of preparing lithium transition metal phosphate according to embodiments of the present invention will be described in detail.
[0038] A method of preparing lithium transition metal phosphate according to an embodiment of the present invention includes: feeding reactants including lithium, a transition metal, and phosphoric acid into a reactor and mixing the reactants at a molecular level in the reactor; and generating a crystal nucleus by chemically reacting the reactants in the reactor, followed by growing the crystal nucleus into a nano-sized crystal. Thereafter, the resultant slurry obtained from the reaction described above is filtered, washed, dried, and/or heated to prepare nano-sized lithium transition metal phosphate (LMP).
[0039] The term ‘lithium’ used herein refers to a lithium compound, a lithium atom, and/or a lithium ion depending on the context, and the term ‘transition metal’ used herein refers to a transition metal compound, a titanium metal atom, and/or a transition metal ion depending on the context. The transition metal may include at least one selected from the group consisting of Fe, Mn, Co, and Ni.
[0040] Also, the term ‘mixing at a molecular level’ refers to mixing at a level at which the respective molecules are mixed. Typically, ‘mixing’ can be classified into as ‘macro-mixing’ and ‘micro-mixing.’ The ‘macro-mixing’ refers to mixing at a vessel scale, and the ‘micro-mixing’ refers to mixing at a molecular level.
[0041] The reactants may be fed in at least one of a solution form and a suspension form into the reactor.
[0042] The reactants may include an acidic source material and a basic source material. In this case, the acidic source material may be fed into the reactor through a first source material feeding line and the basic source material may be fed into the reactor through a second source material feeding line. After the acidic source material and the basic source material are respectively fed into the reactor through the first and second source material feeding lines, the acidic source material and the basic source material are respectively mixed at the molecular level in the reactor and then subjected to a chemical reaction, such as an acid-base reaction, to form LMP nanoparticles.
[0043] The acidic source material may include lithium, a transition metal, and phosphoric acid. For example, the acidic source material may include lithium chloride, a transition metal chloride, and H 3 PO 4 . The acidic source material may be, for example, a LiCl/FeCl 2 /H 3 PO 4 aqueous solution or an aqueous suspension. In this case, the basic source material may include an inorganic base, such as NH 4 OH.
[0044] The acidic source material may include a transition metal and phosphoric acid. The basic source material may include lithium. For example, the acidic source material may include transition metal chloride, such as FeCl 2 , and H 3 PO 4 , and the basic source material may include lithium hydroxide, such as LiOH.
[0045] The acidic source material may include lithium and phosphoric acid. The basic source material may include a transition metal. For example, the acidic source material may include lithium chloride, such as LiCl, and H 3 PO 4 . The basic source material may include a transition metal hydroxide, such as Fe(OH) 2 .
[0046] The basic source material may include lithium and a transition metal. For example, the basic source material may include lithium hydroxide and a transition metal hydroxide. The basic source material may be, for example, a LiOH/Fe(OH) 2 aqueous solution or an aqueous suspension. In this case, the acidic source material may include phosphoric acid, such as H 3 PO 4 , and optionally, another inorganic acid and/or organic acid.
[0047] These lithium chloride, transition metal chloride, lithium hydroxide, transition metal hydroxide, and phosphoric acid are relatively inexpensive, and thus may reduce preparation costs of lithium transition metal phosphate nanoparticles.
[0048] The chemical reaction may be an acid-base reaction during which one equivalent of an acid is reacted with one equivalent of a base in the reactants and thus the acid and the base in the reactants lose their acidic or basic properties.
[0049] A time (T M ) taken to mix the reactants at the molecular level may be shorter than a time (T N ) taken to generate the crystal nucleus.
[0050] The term ‘T M ’ used herein refers to a period of time from when the mixing begins to when a composition of the mixture becomes spatially uniform, and the term ‘T N ’ used herein refers to a period of time from when the generating the crystal nucleus begins to when the crystal nucleus generation rate reaches an equilibrium, thereby remaining constant.
[0051] As described above, by controlling T M to be shorter than T N , the intermolecular mixing is maximized before the generating the crystal nucleus begins in the reactor. By doing so, nano-sized LMP particles having a uniform particle distribution may be obtained. For example, T M may be in a range of 10 to 100 μs and T N may be 1 ms or less. If T M is less than 10 μs, manufacturing costs may be increased, and if T M is greater than 100 μs, uniformity of particle sizes may be reduced. Also, if T N is greater than 1 ms, an appropriate level of reaction may not occur and thus a product yield may become low.
[0052] In preparing LMP nanoparticles, an inner temperature of the reactor may be in a range of 0 to 90° C., for example, 20 to 80° C. If the inner temperature is lower than 0° C., an appropriate product yield may not be obtained. If the inner temperature is higher than 90° C., T N may not be controllable.
[0053] Also, a molar ratio of a total of lithium and transition metal (i.e. Li+M) to phosphoric acid ((Li+M)/phosphoric acid) among the reactants may be in a range of 1.5 to 2.5. If the molar ratio ((Li+M)/phosphoric acid) is less than 1.5, a metal phosphate secondary phase such as LiFeP 2 O 7 and Fe 4 (P 2 O 7 ) 3 may be deposited on the surfaces of the LMP nanoparticles. If the molar ratio ((Li+M)/phosphoric acid) is greater than 2.5, secondary phases such as Li 2 O, Fe 2 O 3 , Fe 2 P, Li 3 PO 4 , and Li 4 P 2 O 7 may be deposited on the surfaces of the LMP nanoparticles.
[0054] A retention time of the reactants in the reactor may be in a range of 1 ms to 10 s, for example, 10 ms to 5 s. If the retention time of the reactants is less than 1 ms, an appropriate level of reaction may not occur, and if the retention time of the reactants is greater than 10 s, controlling a particle size of LMP may be difficult and manufacturing costs may be increased.
[0055] FIG. 1 is a schematic cross-sectional view of a high gravity rotating packed bed reactor 10 that is used in a method of preparing lithium transition metal phosphate according to an embodiment of the present invention.
[0056] The high gravity rotating packed bed reactor 10 may include a chamber 11 delimiting an inner space, a permeable packed bed 12 that is rotatable, is disposed inside the chamber 10 , and is filled with a porous filler 12 a , at least one source material feeding line through which the reactants are fed into the inner space, and a slurry outlet 15 through which a slurry is discharged from the inner space.
[0057] The reactor 10 may further include a gas outlet 16 for discharging a gas from the inner space.
[0058] The porous filler 12 a may include titanium, which is a strong corrosion-resistant material. For example, the porous filler 12 a may be a titanium foam.
[0059] The permeable packed bed 12 may be filled with the porous filler 12 a therein and may allow the reactants fed in a solution or suspension form into the reactor 10 to permeate therethrough, and may be rotatable by a driving axis 13 . A centrifugal acceleration of the permeable packed bed 12 may be maintained in a range of 10 to 100,000 m/s 2 . If the centrifugal acceleration of the permeable packed bed 12 is less than 10 m/s 2 , an appropriate level of reaction may not occur. Meanwhile, the centrifugal acceleration of the permeable packed bed 12 cannot exceed 100,000 m/s 2 in terms of reactor design technology
[0060] Although the reactor 10 having such a structure operates in an atmospheric condition, because the reactants can be mixed at the molecular level by a high centrifugal force by controlling the rotational speed of the permeable packed bed 12 , the reaction may be smoothly performed even at low temperature. That is, because micro droplets of the reactants are well mixed before growth of LMP particles, uniform LMP nanoparticles may be obtained even at low temperature. Use of the continuous reactor 10 ensures production of LMP on a mass scale.
[0061] LMP prepared by the method of preparing lithium transition metal phosphate according to any of the embodiments described above may have an olivine-type crystal structure with an average particle size of from about 0.01 μm to about 10 μm, and in some embodiments, from about 0.05 μm to about 0.8 μm. Accordingly, the obtained lithium transition metal phosphate may be used as a cathode active material for a lithium secondary battery.
[0062] Hereinafter, one or more embodiments of the present invention will be described in more detail with reference to the following examples. However, these examples are not intended to limit the scope of the present invention.
EXAMPLES
Example 1
[0063] (1) 10.0 mol/L of a NH 4 OH aqueous solution was prepared.
[0064] (2) 2.0 mol/L of a LiCl aqueous solution, 2.0 mol/L of a FeCl 2 aqueous solution, and 2.0 mol/L of a H 3 PO 4 aqueous solution were separately prepared and were then mixed together in a volume ratio of 1:1:1. A molar ratio of (Li+Fe) to H 3 PO 4 ((Li+Fe)/H 3 PO 4 ) in the mixed solution of LiCl/FeCl 2 /H 3 PO 4 was 2.
[0065] (3) The reactor 10 of FIG. 1 was manufactured by the inventors of the present invention. The reactor 10 has the following specification.
Permeable packed bed 12 : a cylinder formed of stainless steel and having an inner diameter of 10 cm, an outer diameter of 30 cm, and a thickness of 10 cm Porous filler 12 a : 4 sheets of titanium foam (about 400 pores/m, an outer diameter of 30 cm, an inner diameter of 10.5 cm, and an axis-direction thickness of 2.5 cm)
[0068] (4) To prepare LMP nanoparticles, the driving axis 13 of the reactor 10 was rotated to make the permeable packed bed 12 rotate at a rotational speed of 1440 rpm (centrifugal acceleration: 60,000 m/s 2 ) while the inner temperature of the reactor 10 was maintained at a temperature of 80° C.
[0069] (5) The LiCl/FeCl 2 /H 3 PO 4 mixed solution prepared in the above (2) and the NH 4 OH aqueous solution prepared in the above (1) were continuously fed into the reactor 10 through the first source material feeding line 14 - 1 and second source material feeding line 14 - 2 , respectively, at a flow rate of 30 L/min to prepare LMP nanoparticles.
[0070] (6) A slurry including the LMP nanoparticles was discharged through the slurry outlet 15 .
[0071] (7) The slurry was filtered and washed with water and dried in a drier at a temperature of 120° C. to obtain LMP nanoparticles.
Example 2
[0072] LMP nanoparticles were prepared in the same manner as in Example 1, except that after preparation of 4.0 mol/L of a LiOH aqueous solution, 2.0 mol/L of a FeCl 2 aqueous solution, and 2.0 mol/LH 3 PO 4 aqueous solution, the FeCl 2 aqueous solution and the H 3 PO 4 aqueous solution were mixed in a volume ratio of about 1:1 to obtain a FeCl 2 /H 3 PO 4 mixed solution, and while the inner temperature of the reactor was maintained at about 60° C., the FeCl 2 /H 3 PO 4 mixed solution and the LiOH aqueous solution were continuously fed into the reactor 10 through the first source material feeding line 14 - 1 and second source material feeding line 14 - 2 at a flow rate of 40 L/min and 10 L/min, respectively, to obtain LMP nanoparticles, which were then subjected to filtration, washing, and drying. In the present embodiment, a molar ratio of the reactant components fed into the reactor 10 , i.e., a molar ratio of (Li+Fe) to H 3 PO 4 ((Li+Fe)/H 3 PO 4 ) was about 2.
Example 3
[0073] LMP nanoparticles were prepared in the same manner as in Example 1, except that after preparation of 2.0 mol/L of a LiCl aqueous solution, 2.0 mol/L of a H 3 PO 4 aqueous solution, and 2.0 mol/L of a Fe(OH) 2 aqueous solution, the LiCl aqueous solution and the H 3 PO 4 aqueous solution were mixed in a volume ratio of about 1:1 to obtain a LiCl/H 3 PO 4 mixed solution, and while the inner temperature of the reactor was maintained at about 70° C., the LiCl/H 3 PO 4 mixed solution and the Fe(OH) 2 aqueous solution were continuously fed into the reactor 10 through the first source material feeding line 14 - 1 and second source material feeding line 14 - 2 at a flow rate of 40 L/min and 20 L/min, respectively, to obtain LMP nanoparticles, which were then subjected to filtration, washing, and drying. In the present embodiment, a molar ratio of the reactant components fed into the reactor 10 , i.e., a molar ratio of (Li+Fe) to H 3 PO 4 ((Li+Fe)/H 3 PO 4 ) was about 2.0.
Example 4
[0074] LMP nanoparticles were prepared in the same manner as in Example 1, except that after preparation of 4.0 mol/L of a H 3 PO 4 aqueous solution, 2.0 mol/L of a LiOH aqueous solution, and 2.0 mol/L of a Fe(OH) 2 aqueous solution, the LiOH aqueous solution and the Fe(OH) 2 aqueous solution were mixed in a 1:1 volume ratio to obtain a LiOH/Fe(OH) 2 mixed solution, and while the inner temperature of the reactor was maintained at about 60° C., the H 3 PO 4 aqueous solution and the LiOH/Fe(OH) 2 mixed solution were continuously fed into the reactor 10 through the first source material feeding line 14 - 1 and the second source material feeding line 14 - 2 , at a flow rate of 10 L/min and 40 L/min, respectively, to obtain LMP nanoparticles, which were then subjected to filtration, washing, and drying. In the present embodiment, a molar ratio of the reactant elements fed into the reactor 10 , i.e., a molar ratio of (Li+Fe) to H 3 PO 4 ((Li+Fe)/H 3 PO 4 ) was about 2.0.
[0075] Analysis Example
[0076] Transmission electron microscopic (TEM) images and X-ray diffraction (XRD) patterns of the lithium transition metal phosphate nanoparticles prepared according to Examples 1-4 and Comparative Example were analyzed, and results therefrom are shown in FIGS. 2 to 9 . Specifications and analysis conditions of the TEM and XRD are shown in Table 1 below:
[0000]
TABLE 1
TEM
XRD
Specification
Manufacturer
JEOL
Rikagu
Model name
2100F
D/Max-2500VK/PC
Analysis conditions
200 kV
CuKa radiation,
speed 4° min −1
[0077] Referring to FIGS. 2-9 , though prepared from relatively low-price reactants, LMP particles according to the present invention are found to have relatively uniform particle size distributions and nano-sizes. In particular, it is clear from FIGS. 2 , 4 , 6 and 8 that the LMP particles of Examples 1 to 4 have nano-sizes and uniform particle size distributions. Also, from FIGS. 3 , 5 , 7 and 9 , it was confirmed that the obtained particles are LMP (LiMPO 4 ). For reference, the respective numerals (for example, 100 nm in FIG. 2 ) shown in FIGS. 2 , 4 , 6 , ad 8 denote lengths of bold bars in the respective images, and the respective numerals (for example, ( 111 ) of FIG. 3 ) shown in FIGS. 3 , 5 , 7 , and 9 indicate facial indices.
[0078] While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the following claims. | Disclosed is a method for manufacturing a lithium transition metal phosphate. The disclosed method for manufacturing a lithium transition metal phosphate comprises the steps of: injecting reaction materials containing lithium, a transition metal, and a phosphate, into a reactor, and mixing the raw materials at the molecular level in the reactor; and allowing the reaction materials to chemically react in the reactor so as to cause nucleation. | 2 |
BACKGROUND OF THE INVENTION
Flexible copolymers of p-(hydroxyalkoxy) benzoic acid or its methyl ester are disclosed in U.S. Ser. No. 253,418. As set forth in the "Background of the Invention" in that application, p-(hydroxyalkoxy) benzoic acids had been used in fibers and films which exhibited good strength, but their copolymerization with flexible chain components to produce flexible copolyesters had not been suggested. The present invention comprises a novel diester and method of making the same which diester may be used to produce the p-(hydroxyalkoxy) benzoic acids or their methyl esters of the prior application or to produce the flexible copolyesters of the prior application directly from the diester, without the intermediate step of producing the p-(hydroxyalkoxy) benzoic acid or its methyl ester. The use of the diester produces greater yields and enhanced purity of the p-(hydroxyalkoxy) benzoic acid or its methyl ester.
SUMMARY OF THE INVENTION
The present invention comprises a novel family of diesters, methyl p-(ω-acetoxyalkoxy) benzoate having the following structural formula: ##STR1## where m=2 to 6. The novel method of producing the diester comprises O-alkylation of methyl(p-hydroxy) benzoate using a α,ω acetoxyhaloalkane in the presence of an organic solvent and a suitable base under substantially anhydrous conditions.
The invention also comprises the novel process for producing methyl p-(ω-hydroxy-n-alkoxy) benzoate by the acid catalyst alcoholysis of the diester. The invention also comprises the method of self-condensation of the diester, and of producing copolyesters from the diester monomers.
DESCRIPTION OF THE INVENTION
The novel diesters of the present invention may be produced by the O-alkylation of methyl (p-hydroxy) benzoate using an α,ω acetoxy bromo- or chloro-n-alkane, in the presence of a suitable base and an organic solvent, under substantially anhydrous conditions. A typical reaction scheme is set out below: ##STR2## where X=Br, Cl and m=2-6, and preferably is 4. Another suitable base, for use alone or in conjunction with potassium iodide, is sodium carbonate. The following are examples for the preparation of diester.
Example 1: Methyl p-(4-acetoxybutoxy) benzoate
Into a 2 l. 3-necked flask fitted with a stirrer and reflux condenser and topped by a drying tube were placed 152 g (1.0 M) of methyl p-hydroxybenzoate, 197 g (1.01 M) of 4-bromobutyl acetate, 20 g (0.12 M) potassium iodide and 750 ml of dry acetone. To this was added 140 g (1.0 M) of anhydrous potassium carbonate powder. The mixture was refluxed while stirring for 48 hours. The mixture was filtered, the precipitate was washed with 100 ml of acetone and the filtrates were combined and evaporated to dryness. The solid residue was triturated with 1 l. of water, the mixture was filtered and the solid was washed thoroughly with water until the pH of the filtrate was neutral. The product was dried overnight in a nitrogen filled circulating forced gas oven. The dried product was washed well with 2 l. of either petroleum ether or hexane. After another drying cycle there remained 243.9 g (91.6%) of product, m.p. 49°-51° C.
Material of highest purity could be obtained by recrystallization in absolute ether or toluene, giving a yield of 193.7 g (72.7% overall yield corresponding to 79% recovery upon recrystallization) of melting point 52°-54° C.
A repetition of the procedure on a 15 M scale in which granular instead of powdered anhydrous potassium carbonate was employed gave a 95.7% yield of product, m.p. 54° C.
Example 2: Methyl p-(2-acetoxyethoxy) benzoate
Methyl p-hydroxy benzoate (15.2 g, 0.1 moles), 2-bromoethylacetate (16.7 g, 0.1 moles, b.p.=158°-159° C., η D 23 =1.4548), anhydrous K 2 CO 3 (13.8 g, 0.1 moles), and anhydrous KI (1.7 g, 0.01 moles) were refluxed in 76 ml of acetone, with thorough mixing, for 68 hours. After filtration of the reaction mixture, the liquid portion of the reaction mixture was placed on a rotary evaporator and the acetone was distilled off at room temperature. Acetone evaporation produced an oil, which crystallized upon standing at room temperature. This solid was then extracted with 75 ml of diethyl ether. Ether evaporation yielded 11 g of solid product. Two recrystallizations of this solid from toluene produced a sample which melted from 76° to 78° C.
The novel diesters may be used to form the corresponding methyl p-(ω-hydroxyalkoxy) benzoates which may be used to form flexible copolyesters as set forth in U.S. Ser. No. 253,418. The acid catalyzed alcoholysis of the diesters can be used to yield the corresponding monomeric hydroxyesters according to the following scheme: ##STR3## where H + is an inorganic (e.g. H 2 SO 4 ) or an organic acid and m=2-6. Examples of suitable organic acid catalysts are p-toluene sulfonic acid and sulfonated polystyrene. An example of the preparation of methyl p-(ω-hydroxyalkoxy) benzoate from the diester is set out below.
Example 3: p-Methyl p-(4-hydroxybutoxy)benzoate
A solution containing 3990 g (15.0 M) of methyl p-(4-acetoxybutoxy) benzoate, 80 g p-toluenesulfonic acid (0.42 M) and 12 l. absolute methanol was stirred while refluxing in a 22 l. three-necked flask for four hours. Six liters of methanol were distilled off at atmospheric pressure and the remainder of solvent at reduced pressure. The residue was dissolved in 12 l. toluene and the solution was washed twice in portions with one-half volumes of water (this usually led to a pH of 4 for the second water wash). The washed toluene solution was dried over anhydrous sodium sulfate. After removal of the drying agent by filtration, the filtrate was cooled overnight to yield a crude crystalline product. This was filtered off and washed with petroleum ether or hexane and air dried. The yield of this first crop was 2047 g, m.p. 48°-52° C. A second crop of 525 g (m.p. 46°-48° C.) was obtained by condensing the toluene filtrate to one-half volume and repeating the procedure used in the isolation of the first crop. The combined yield was 2572 g (76.5%).
By this method the overall yield based on methyl p-hydroxybenzoate was 73.2%.
The preparation of methyl p-(ω-hydroxyalkoxy) benzoate according to the present invention has several advantages over the method disclosed in U.S. Ser. No. 253,418, including a greater initial and/or greater overall yield (73.2% reported as compared with about 35% using the method disclosed in U.S. Ser. No. 253,418). The diester intermediate is a novel composition and can be purified more readily by recrystallization than p-(4-hydroxybutoxy) benzoic acid for it has optimum solubility in a greater number of organic solvents. Use of the diester intermediate provides economy by reducing the amount of waste organic and inorganic by-products. In addition, the diester intermediate is easily purified and yields a high purity monomer of methyl p-(ω-hydroxyalkoxy) benzoate.
The diesters may also self-condense to a homopolymer according to the following reaction scheme: ##STR4## where the catalyst is an organo-metallic and/or inorganic catalyst containing one or more of the following transition elements: Sn, Sb, Pb, Ti. Heat is required in an amount sufficient for the formation of the homopolymer without destroying the starting materials or product. The reaction must be carried out in an inert atmosphere. The following examples illustrate methods for producing the C-2 and C-4 homopolymers.
Example 4: Formation of poly(ethoxybenzoate) (PEB)
Under a dry nitrogen atmosphere, the following materials were placed into a flame and vacuum dried 10 ml round-bottom flask, equipped with a short distilling head fitted with a receiver and a gas inlet nozzle:
______________________________________1.0 g methyl p-(2-acetoxyethoxy) benzoate (0.0042 mol)0.004 g dibutyltin oxide______________________________________
The entire charge-containing assembly was removed from the nitrogen atmosphere and exposed to a high (less than 1 mm) vacuum for several hours. The charged reaction vessel was vented with nitrogen, and then heated to 100° C. After thorough mixing for 15 minutes at this temperature, the reaction mixture was subjected to the following heating scheme: 200° C. for 3.0 hours, 230° C. for 5.25 hours, and 250° C. for 1.25 hours. As the distillation of volatile byproducts slowed after 1.25 hours at 250° C., the receiver containing the distillate was replaced with an empty receiver. Then gradually over the course of 0.75 hours the pressure in the reaction flask was reduced to 0.05 mm. Under reduced pressure the reaction mixture was heated at 250° C. for 2.75 hours. At the end of this heating cycle, the reaction vessel was removed from the oil bath, equilibrated with nitrogen, and then allowed to cool to room temperature. The polymer was isolated after chilling in liquid nitrogen and then ground and dried.
Example 5: Formation of poly(p-n-butoxybenzoate) (PBB)
Under a dry nitrogen atmosphere, the following materials were placed into a flame and vacuum dried 100 ml two-neck, round-bottom flask, equipped with a paddle stirrer, a short distilling head fitted with a receiver and a gas inlet nozzle:
______________________________________34.6 g methyl para(4-acetoxybutoxy) benzoate (0.1301 mol)0.1 g dibutyltin oxide______________________________________
After stoppering the open neck of the flask, the entire charge-containing assembly was removed from the nitrogen atmosphere and exposed to a high (less than 1 mm) vacuum for several hours. The charged reaction vessel was then vented with nitrogen, and heated to 100° C. Once the charge was liquified, the reaction flask was connected to an efficient mechanical stirrer and thorough mixing at 100° C. was performed for 15 minutes. Still under a continuous flow of nitrogen, the melted reaction mixture was then subjected to the following heating sequence: 200° C. for 2.5 hours, 230° C. for 2.5 hours, and 250° C. for 1.5 hours. As the distillation of the volatile by-products slowed after 1.5 hours at 250° C., the receiver containing the distillate was replaced with an empty receiver. Then gradually over the course of 0.75 hours the pressure in the reaction flask was reduced to 0.05 mm. Under reduced pressure the reaction mixture was heated at 250° C. for 6.0 hours. At the end of this heating cycle, the reaction vessel was removed from the oil bath, equilibrated with nitrogen, and then allowed to cool to room temperature. The polymer was isolated after chilling in liquid nitrogen and then ground and dried for 8 hours at 80° C. high vacuum.
The resulting polymer is a good fiber former, as indicated by the value of inherent viscosity set out in the appended chart.
The diesters may also be used to form copolyesters directly, without proceeding through the step of forming methyl p-(4-hydroxybutoxy) benzoate. The process comprises mixing the diester with another suitable ester in an inert atmosphere, and heating in the presence of an organometallic and/or inorganic catalyst containing one or more of the following transition elements: Sn, Sb, Pb, Ti, to form the copolyester. The amount of heat applied is suitable for formation of the copolyesters without destroying the reactants or product. Three examples of copolyester formations are set out below.
Example 6: Preparation of 76/24 PBB/C 18 Succinate copolyester
Under a dry nitrogen atmosphere, the following materials were placed into a flame and vacuum dried 100 ml two-neck, round-bottom flask, equipped with a paddle stirrer, a short distilling head fitted with a receiver and a gas inlet nozzle:
______________________________________26.3 g methyl para(4-acetoxybutoxy)benzoate (0.0989 mol)4.7 g 2-octadecenyl succinic anhydride (0.0133 mol)1.7 g 1,6-hexanediol (0.0144 mol)0.1 g dibutyltin oxide______________________________________
After stoppering the open neck of the flask, the entire charge-containing assembly was removed from the nitrogen atmosphere and exposed to a high (less than 1 mm) vacuum for several hours. The charged reaction vessel was then vented with nitrogen, and heated to 100° C. Once the charge was liquified, the reaction flask was connected to an efficient mechanical stirrer and thorough mixing at 100° C. was performed for 15 minutes. Still under a continuous flow of nitrogen, the melted reaction mixture was then subjected to the following heating sequence: 200° C. for 1.0 hours, 230° C. for 2.0 hours, and 250° C. for 8.25 hours. As the distillation of volatile by-products slowed after 8.25 hours at 250° C., the receiver containing the distillate was replaced with an empty receiver. Then gradually over the course of 0.75 hours the pressure in the reaction flask was reduced to 0.05 mm. Under reduced pressure the reaction mixture was heated at 250° C. for 7.3 hours. At the end of this heating cycle, the reaction vessel was removed from the oil bath, equilibrated with nitrogen, and then allowed to cool to room temperature. The polymer was isolated after chilling in liquid nitrogen and then ground and dried for 8 hours at 80° C. under vacuum. The fiber-forming characteristics of this copolymer are set out in the attached chart.
Example 7: Preparation of 78/22 PBB/C 18 Succinate
Under a dry nitrogen atmosphere, the following materials were placed into a flame and vacuum dried 100 ml two-neck, round-bottom flask equipped with a stainless steel paddle stirrer, a short distilling head fitting with a receiver, and a gas inlet nozzle:
______________________________________32.4 g Methyl p-(4-acetoxybutoxy) benzoate (0.1218 mol)5.1 g 2-octadecenyl succinic anhydride (0.0144 mol)1.7 g 1,6-hexanediol (0.0144 mol)0.03 g Butylstannoic acid______________________________________
After stoppering the open neck of the flask, the entire charge-containing assembly was removed from the nitrogen atmosphere and exposed to a high (less than 1 mm) vacuum for several hours. The charged reaction vessel was then vented with nitrogen, and the reactants liquified by heating to 100° C. Once the charge was liquified, the reaction flask was connected to an efficient mechanical stirrer and thorough mixing at 100° C. was performed for 15 minutes. Still under a continuous flow of nitrogen, the melted reaction mixture was then subjected to the following heating sequence: 190° C. for 2.5 hours, 220° C. for 2.0 hours, and 240° C. for 2.0 hours. The reaction was then cooled to room temperature. Next a catalyst (0.48 ml), consisting of a mixture of tetrabutyl orthotitanate and magnesium acetate dissolved in a mixture of methanol and butanol, was quickly syringed into the reaction vessel via the side arm. Under a continuous flow of nitrogen, the reaction mixture was next heated according to the following scheme: 220° C. for 1.0 hours and 240° C. for 2.5 hours. As the distillation of volatile by-products slowed after 2.5 hours at 240° C., the receiver containing the distillate was replaced with an empty receiver. Then gradually over the course of 0.75 hours the pressure in the reaction flask was reduced to 0.05 mm. Under reduced pressure the reaction mixture was subjected to the following heating scheme: 240° C. for 3.0 hours and 255° C. for 5.5 hours. At the end of this heating cycle, the reaction vessel was removed from the oil bath, equilibrated with nitrogen, and then allowed to cool to room temperature. The polymer was isolated after chilling in liquid nitrogen and then ground and dried for 8 hours at 80° C. under vacuum.
Example 8: Preparation of 78/22 PBB/C 18 Succinate
Under a dry nitrogen atmosphere, the following materials were placed into a flame and vacuum dried 100 ml two-neck, round-bottom flask equipped with a stainless steel paddle stirrer, a short distilling head fitting with a receiver, and a gas inlet nozzle:
______________________________________32.4 g Methyl para-(4-acetoxybutoxy) benzoate (0.1218 mol)5.1 g 2-octadecenyl succinic anhydride (0.0144 mol)1.7 g 1,6-hexanediol (0.0144 mol)______________________________________
After stoppering the open neck of the flask, the entire charge-containing assembly was removed from the nitrogen atmosphere and exposed to a high (less than 1 mm) vacuum for several hours. The charged reaction vessel was then vented with nitrogen, and the reactants were melted by heating to 100° C. Once the charge was liquified, the reaction flask was connected to an efficient mechanical stirrer and thorough mixing at 100° C. was performed for 15 minutes. Next, the catalyst (0.56 ml), consisting of a mixture of tetrabutyl orthotitanate (0.1370 g.) and magnesium acetate (0.0056 g.) dissolved in a mixture of methanol and butanol, was quickly syringed into the reaction vessel via the side arm. Still under a continuous flow of nitrogen, the melted reaction mixture was then subjected to the following heating sequence: 190° C. for 2.5 hours, 220° C. for 2.0 hours, 240° C. for 4.0 hours, and 250° C. for 7.0 hours. As the distillation of volatile by-products slowed after 7.0 hours at 250° C., the receiver containing the distillate was replaced with an empty receiver. Then, gradually over the course of 0.75 hours the pressure in the reaction flask was reduced to 0.05 mm. Under reduced pressure the reaction mixture was subjected to the following heating scheme: 240° C. for 2.5 hours, 250° C. for 2.5 hours, and 260° C. for 2.0 hours. At the end of this heating cycle, the reaction vessel was removed from the oil bath, equilibrated with nitrogen, and then allowed to cool to room temperature. The polymer was isolated after chilling in liquid nitrogen and then ground and dried for 8 hours at 80° C. under vacuum.
It will be understood by those skilled in the art that variations and modifications of the specific embodiments described above may be employed without departing from the spirit and scope of the invention as defined in the appended claims.
__________________________________________________________________________EXTRUSIONS & DRAWING CONDITIONS AND TENSILE PROPERTIES OFMONOFILAMENTS DERIVED FROM DIESTER POLYMERS Extrusion Young's ηinh Conditions Draw Conditions Knot Str. Modulus (@ 25° C. ηapp Ratio/Temp (°C.) Dia. × 10.sup.-3 × 10.sup.-3 Elong. × 10.sup.-3Description in HFIP) T*.sub.M °C. (poise) 1st stage 2nd stage (mil) (psi) (psi) (%) (psi)__________________________________________________________________________PBB 0.63 176-179 195 3472 4/56 1.375/75 9.4 43.2 60.5 20 632.6(Example #5)76/24 PBB/ 0.60 132-142 160 3975 4/63 1.5/78 7.7 31.1 45.1 41 52.1C.sub.18 Succinate(Example #6)PEB 0.21 209-213(Example #4)__________________________________________________________________________ *by microscopy | A novel family of diesters, methyl p-(ω-acetoxyalkoxy) benzoate wherein the alkoxy group has a chain length of 2 to 6, the method of preparation of the diesters, polymerization of the diesters and their use to form methyl p-(ω-hydroxy-n-alkoxy) benzoate. | 2 |
BACKGROUND OF THE INVENTION
The invention relates to a portable surface processing apparatus with two oppositely motor-driven rotor cages with horizontal axes, a plurality of processing elements arranged on cage bars of the cages, and adjustable wheels arranged to raise and lower the rotor cages.
Such apparatuses are known, for example, from U.S. Pat. No. Des. 252,880 and are constructed both as hand tools, as well as larger apparatus movable on rollers. In such apparatus the rotor can be driven both by an electric motor, and by a combustion motor. An alternative drive can also be a pneumatic motor.
The apparatus serves for surface processing, such as rust removal from relatively large surfaces, removing old paint, cleaning dirty concrete floors, etc. The processing remains restricted to the surface; the processing depth is, to be sure, adjustable, but only slightly. The processing is accomplished by the processing elements arrayed on the rotor cage bars, such as, for example, blades.
The above-mentioned known apparatuses have only one rotor cage. This has the disadvantage that the processing force acts in one direction upon the surface being treated, so that the apparatus has the tendency to move automatically in one direction. In the opposite direction, however, it can be shifted only with difficulty. This undesired reaction force is especially pronounced in the case of relatively heavy and larger apparatus.
From German Pat. No. 509,435 and U.S. Pat. No. 2,588,707 there are known, further, surface processing machines with two oppositely motor-driven rotors which are suited for shaving, grinding or polishing of wood floors. The rotors of these patents rest directly on the surface to be processed.
SUMMARY OF THE INVENTION
The invention provides a surface-processing apparatus of the type mentioned, in which the reaction force previously felt as a disadvantage can be utilized desirably. The invention provides two rotor cages borne turnably on a chassis that is provided with wheels which are arranged in each case on the lower end of a two-armed pivot lever. On the upper ends of these pivot levers is located a connecting rod. The upper arms of the two-armed pivot lever together with the connecting rod and the connecting line of the pivot axes form an angle-adjustable parallelogram, in which the angle adjustment brings about a change of the relative position of the chassis with respect to the surface to be processed.
DESCRIPTION OF THE DRAWINGS
The drawings show an example of a preferred embodiment of the invention, in which
FIG. 1 illustrates a side view of a portable surface processing apparatus,
FIG. 2 illustrates the two rotors of the apparatus in greater detail and on a larger scale as well as two other blades by themselves,
FIG. 3 illustrates the mechanism for the elevational adjustment, and
FIG. 3a illustrates the drive of the rotors.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The apparatus represented in FIG. 1 resembles on superficial examination a lawnmower with motor drive. The apparatus is equipped with an internal combustion motor M. This is secured to the chassis, which is designated generally with 1.
The chassis 1 is provided with two rear wheels 11 and one front wheel 12. To the back of the chassis 1 there is rigidly fastened a steering thrust device 2, which extends upward at an angle of about 45°. To the upper end of the device 2 are fastened two spaced steering handles 21, with which the apparatus is steered. The height of the chassis 1 over the surface F to be processed is adjusted by means of a lever 22. With the aid of the knob 23 the elevational setting of the front wheel 12 with respect to the two rear wheels 11 can be adjusted, as described in detail below.
In the interior of the chassis 1, two rotors R 1 , R 2 are mounted to be driven in opposite directions by the motor M. On the side visible in FIG. 1 the bearings for the rotors R 1 , R 2 are arranged on a removable plate 13. When the plate 13, which is fastened to the chassis 1 by means of screws, is removed together with the bearings fastened to it, it is possible to take out the two rotor cages together with the blades fastened to them and change or check them. In operation the processing blades are subject to a certain amount of wearing down and after a certain time of operation they must be replaced or re-equipped.
In FIG. 2 the two rotors R 1 , R 2 are shown by themselves. Rotor R 1 is in elevation and rotor R 2 is represented in section. Each rotor has a cage which comprises two spaced side plates 30, a hollow hexagonal shaft 31 and four cage bars 32 extending between the side plates 30. One of the two side plates 30 is detachable from the cage bars so that processing bodies L 1 , L 2 , L 3 , or L 4 can be mounted on the cage bars 32, or removed and changed. The hollow hexagonal shafts 31 extend from the drive shafts firmly borne on one side of the chassis 1. The processing elements L can present various forms according to the surface to be processes. All elements intended for the apparatus have the same outside processing diameter D and a bore with the same diameter d 1 , which is greater than the diameter d of the cage bars 32 on which they are arrayed.
The elements L 1 have the form of pentagonal blades which have hard metal tips. The processing elements L 2 , in contrast, are triangular blades which merely have hardened points. Rotor R 1 is equipped, for example, with quadrangular blades L 3 with hard metal inserts and rotor R 2 has processing elements L 4 in the form of milling tools with hard metal tips.
FIG. 2 shows the rotors during operation, in which case the processing elements, insofar as their bore admits, are pushed radially outward by centrifugal force. The arrows 33 and 34 indicate the rotational direction. The rotation is chosen in such a way that it is directed away from one another on the side of the surface to be processed. Thus, the material removed from the surface, i.e., dust or shavings, is flung outward. If the turning direction of the rotors are directed one against the other on the side of the surface to be processed, the removed material would accumulate between the rotors.
The parts serving for the elevational adjustment are represented in FIG. 3. The same parts as in FIG. 1 are provided with the same reference symbols. The wheels 11 and 12 are each fastened to the end of a two-armed lever 14, 15, which are swingable about fixed axes 16 and 17, respectively. The other ends of the levers 14, 15 are joined with one another through a connecting rod 18, so that they form a parallelogram.
A rod 24 is attached to the lever 14 and leads to the adjusting lever 22. The lever 22 pivots about an axis 25 arranged in part 2. A shifting of the lever 22 leads, therefore, to an angle adjustment of the parallelogram 14, 15, 18 and thereby to an elevational adjustment of the chassis 1 with respect to the surface F, which leads to a change of the processing intensity of the blade-fitted rotors R 1 , R 2 . So that it will be possible for this elevational adjustment to be carried out by means of the relatively short lever 22, there is arranged a weight-compensation spring (omitted in the drawing in the interest of clarity) which is constructed as a tension spring and which extends from an eye 19 on the chassis to the rod 24.
The above-described parts permit a like and simultaneous elevation adjustment of both the wheels 11, 12. A separate, slight alteration of the elevation adjustment of the front wheel 12 can be achieved by a length change of the connecting rod 18. It is connected by means of connections 40, 41 with the upper ends of the levers 14, 15. Connection 40 is constructed as a sleeve 42 with lateral pivots. In the sleeve 42 there is borne turnably but axially fixed a threaded pin 43, the threaded part of which is screwed into a female thread in the connecting rod 18. A rotation of the threaded pin in one or the other direction, therefore, results in an increase or a reduction of the distance between the connections 40, 41. The turning of the threaded pin is accomplished by rotation of the knob 23, the movement of which is transferred over the rod 44 and a Cardan joint 45 to the threaded pin 43.
FIG. 3a schematically shows how the drive in opposite directions from the drive motor M is accomplished. On the drive shafts of the rotors R 1 , R 2 and on the shaft of the motor there are arranged gear belt pulleys 50, 51, 52 and beside the belt pulley 51 there is a freely turnable deflecting roll 53. The rotors are driven by means of a belt Z toothed on both sides. The belt is covered by means of a hood 24 (FIG. 1).
OPERATION
With Motor M running and setting of the lever 22 about in the position as shown in FIGS. 1 and 3, the rotors R 1 , R 2 turn in opposite directions, without the blades L touching the surface F. If now lever 22 is slid forward about the axis 25, the chassis 1 descends and the blades contact the processing surface F. When the lever 22 is swung further forward, the chassis descends further and the processing becomes more intensive. The processing strength can in this manner be adjusted very finely and sensitively from zero up to the maximum.
The apparatus of the invention behaves neutrally and can be driven forward or backward over the surface to be treated with the aid of the two steering handles 21.
Instead of an internal combustion motor M it is also possible to use an electric motor or a compressed-air motor. In the case of use of a pneumatic motor the waste air of the same can be used to blow away the abrasions or the shavings. Instead of a belt geared on two sides of the drive of the rotors it would also be possible to use a chain. | A portable surface processing apparatus which has two rotors (R 1 , R 2 ) fitted with blades driven in opposite directions by a motor (M). The reaction forces arising in the processing therefore mutually cancel each other. | 8 |
FIELD OF THE INVENTION
[0001] The invention relates to a negative photoresist composition, and more particularly to a negative photoresist composition that contains polyimide.
BACKGROUND OF THE INVENTION
[0002] As the trend in product development becomes more miniaturized, the use of flexible substrates with high density also flourishes. To fulfill the demand of high density and fine pitch, the material used as the encapsulation film in flexible substrate has to possess better heat endurance capability, dimensional stability, electrical properties, and chemical resistance. The drilling techniques employed during processing of traditional flexible substrates, such as pre-punching or pre-drilling, can only achieve a minimal opening diameter of 800 μm, and other techniques like screen printing drilling can only achieve a minimum of 300 μm. On the other hand, though laser drilling can achieve a minimal opening diameter of 25 μm, its high production cost renders it uncompetitive. To solve this problem, the photosensitive encapsulation film materials are adopted, and by utilizing the lithography process, fine and precise patterns can be obtained. However, the photosensitive materials are mostly composed of epoxy resin and acrylic resin, both of which do not possess sufficient heat endurance capability and mechanical strength as a encapsulation film for applications in advanced products. Moreover, in regard to fulfilling the demand of halogen-free and phosphorus-free from the perspective of environmental protection, the UL-94V0 flame retardancy requirement to the epoxy resin and acrylic resin is a major obstacle. The photosensitive polyimide (PSPI) material has excellent heat stability and good mechanical, electrical, and chemical properties. PSPI can meet UL-94V0 flame retardancy requirement without the addition of flame retardants, and it does not need to be concerned with the issue of halogen-free and phosphorus-free, which makes PSPI an ideal material for use in the advanced flexible substrates with high density and fine pitch.
[0003] Traditional PSPI is usually consisted of polyamic acid and polyamide ester, both of which are its precursors and require a curing temperature as high as 350° C. to form polyimide after the lithography process. Such temperature gives rise to the problem of oxidation of copper circuits; and also the problem of excessive shrinkage to polyimide. Moreover, the thickness of encapsulation film produced this way is mostly less than 10 μm, which cannot satisfy the requirement of a thicker film of 20 μm or more.
[0004] Soluble PSPI materials are used as the encapsulation film for advanced flexible substrates, as can be shown in US2003/0176528, US2004/0247908, US2004/0265731, and US2004/0235992. Although they can be cured at a lower temperature of 230° C., the high percentage of photosensitizing particles (acrylic acid ester) contained therein also leads to the problem of worse flame retardancy. This problem necessitates the addition of flame retardants that contain phosphorus or halogen, which cannot meet the demand of halogen-free and phosphorus-free in the future.
[0005] Although soluble PSPI materials have a lower post-curing temperature, their solvent resistance are generally worse and require alkaline developing solution at high concentration to develop images, which reduces their applicability. In Reactive & Functional Polymers; 2003, 56, 59-73, JP2002341535 and JP2003345007; Masao Tomoi and colleagues have proposed a soluble polyimide having carboxyl groups on its backbone, and acrylic acid (ester) monomers having a tertiary amino group to react with the carboxyl groups to give rise to ionic bonds, thereby forming a negative PSPI material. Because the strength of ionic bonding is not as strong as covalent bonding, the PSPI materials having ionic bonding is suitable in the case where a thickness of PSPI film is 10 μm or less. If a thicker PSPI film (20 μm) is required, its exposure energy can reach as high as 8000 mj/cm 2 , which renders it unapplicable. Furthermore, the PSPI film resulted from post-curing has worse solvent resistance and alkaline resistance due to the presence of the aforementioned ionic bonding.
SUMMARY OF THE INVENTION
[0006] A primary objective of the present invention is to provide a negative photoresist composition (photosensitizing polyimide (PSPI) material) free from the drawbacks of the prior art techniques.
[0007] In accordance to the present invention, the negative photoresist composition is composed of: (a) a polyimide having pendant carboxyl groups, wherein a portion of the carboxyl groups reacted with glycidyl (meth)acrylate monomers to form covalent bonds, and the remaining portion of carboxyl groups reacted with (b) monomers having a tertiary amino group and a C═C double bond to form ionic bonds. The negative photoresist composition of the present invention further contains (c) a photoinitiator, also called a photosensitizer. The components (a) to (c) are all dissolved in a solvent.
[0008] The negative photoresist composition proposed by the present invention is mainly consisted of polyimide, thus it does not require post-curing at high temperature, which meets the demand of high density and fine pitch for encapsulation film used in advanced flexible substrate. Because glycidyl (meth)acrylate monomers are bonded to the backbone of polyimide, the negative photoresist composition of the present invention can be used to form thick films that have excellent film residual rate, whereas component (b) in the negative photoresist composition of the present invention can facilitate the completion of developing procedure with an alkaline solution after exposure.
DETAILED DESCRIPTION OF THE INVENTION
[0009] The present invention provides a negative photoresist composition (a photosensitizing polyimide material), it can be used as an encapsulation film of flexible copper clad laminate to protect the fragile copper circuits on the laminate; and it can also be used as the solder mask during assembly.
[0010] The negative photoresist composition of the present invention comprises the following components dissolved in a solvent: a) a polyimide having the following chemical structure (I); b) an unsaturated vinyl monomer that contains a tertiary amino group; and c) a photoinitiator. The amount of photoinitiator is 0.1-30% based on the weigh of the solid content of the polyimide (I), the amount of the monomer is 70-130% of the moles of the carboxyl group contained in polyimide (I), preferably 90-110%,
and in the chemical structure (I)
Ar 1 is a tetra-valent radical;
Ar 2 is a bivalent radical;
Ar 3 is a bivalent radical that contains a carboxyl group;
Ar 4 is a bivalent radical that contains —CH 2 —C(OH)H—CH 2 —O—C(O)—C(R)═CH;
in which R is H or a methyl group;
m+n+o=1,0.1≦n+o≦0.6, and n:o=9:1˜4:6, preferably, n:o=3: 1˜1:1.
[0011] Preferably, m=0.3˜0.7.
[0012] Preferably, Ar 3 is
[0013] Preferably, Ar 4 is
wherein R* is —CH 2 —C(OH)H—CH 2 —O—C(O)—C(R)═CH, in which R is H or a methyl group.
[0014] Preferably, the monomer is tertiary amino C1-C4 alkyl acrylate or methacrylate, or N-(tertiary amino C1-C4 alkyl)acrylamide or methacrylamide.
[0015] Preferably, Ar 1 is selected from
[0016] Preferably, Ar 2 is selected from
wherein i is an integer of 1-20, and X 1 is
wherein i is an integer of 1-20, and Z is H or a methyl group.
[0017] A suitable process for producing the polyimide a) contained in the negative photoresist composition of the present invention comprising the following steps:
[0018] reacting dianhydride, a first diamine and a second diamine in a solvent to form a polyamic acid, wherein the first diamine contains a carboxyl group, and the dianhydride and the second diamine can be those used in the conventional process for preparing a polyimide;
[0019] adding a solvent with a high boiling point to the reaction mixture containing the polyamic acid and carrying out a chemical cyclization reaction of the polyamic acid to form a polyimide, wherein the solvent with high boiling point and the temperature of the chemical cyclization reaction can be the same used in the conventional process for preparing a polyimide via chemical cyclization reaction; and
[0020] adding glycidyl (meth)acrylate to the mixture containing polyimide, and the glycidyl group reacting with a portion of the carboxyl group of the polyimide at a temperature between 60-130° C., so that a side chain of —CH 2 —C(OH)H—CH 2 —O—C(O)—C(R)═CH is formed on the backbone of polyimide, in which R is H or a methyl group. During the reaction, if the reaction temperature is too high, the C═C double bond will break and give rise to crosslinking, and thus an inhibitor can be added to inhibit the crosslinking, if necessary.
[0021] In the carboxyl group of the polyimide, there should be 10-60% of the COOH radical in the formation of the covalent bond —COOR* with (meth)acrylate, if more than 60% of the COOH radical are in the formation of the covalent bond —COOR*, the developing time of the negative photoresist composition of the present invention would be too long; if it is lower than 10%, the negative photoresist composition of the present invention cannot withstand the developing solution, and its photosensitivity and residual film thickness are reduced.
[0022] By adding the monomer b) having the tertiary amino group and a C═C double bond and the photoinitiator c) to the polyimide prepared according to the process described above, the preparation of the negative photoresist composition of the present invention is completed. If necessary, a solvent like N-methyl-2-pyrrolidone (NMP), N,N-dimethylacetamide (DMAc), γ-butyrolactone (GBL), xylene, and toluene can be added to adjust the viscosity of the composition so that it can be applied as a coating adequately.
[0023] Because the tertiary amino group of the monomer b) can react with COOH and form a salt bridge, this helps shorten the developing time and increase photosensitivity of the negative photoresist composition of the present invention. The monomer b) can be one of the following structures or its mixture, but is not limited thereto:
[0024] The mole ratio between the monomer b) having the tertiary amino group and C═C double bond, and the residual COOH radical on the backbone of polyimide is 1:1.
[0025] To increase the crosslinking density of the negative photoresist composition of the present invention, a multi-functional acrylate can be added including (but not limited thereto) ethyleneglycol dimethacrylate, bisphenol A EO-modified diacrylate (n=2−50) (EO is ethyleneoxide, n is the mole of the added ethyleneoxide), bisphenol F EO-modified diacrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, tris(2-hydroxy ethyl) isocyanurate triacrylate. The amount of addition cannot exceed 30% of the weight of the solid content of the polyimide, if more than 30% is added, the flame retardancy and mechanical properties of the negative photoresist composition of the present invention would be adversely affected. Preferably, the amount of addition should be more than 10%, if it is lower than 10%, the crosslinking density cannot be increased, and the ability of withstanding the developing solution is less improved.
[0026] The photoinitiator c) generates free radicals after exposure, thereby promoting the crosslinking between monomers with C═C double bonds. The preferable exposure wavelength of the photoinitiator is between 350 nm to 450 nm. Its photoefficiency decreases and results in insufficient crosslinking between monomers if the wavelength is outside this range. The photoinitiator c) of the present invention includes (but not limited thereto) the following: bis(2,4,6-trimethylbenzoyl)-phenylphosphineoxide, 2-benzyl-2-dimethylamino-1-1(4-morpholinophenyl)-butanone, 2,4,6-trimethyl benzoyl)diphenyl phosphine oxide, bis(.eta.5-2,4-cyclopentadien-1-yl)-bis(2,6-dufluoro-3-(1H-pyrrol-1-yl)-phen yl titanium, 4,4′-bis(dimethylamino)benzophenone, 4,4′-bis(diethylamino)benzophenone, N-phenyldiethanolamine. The amount of the photoinitiator c) to be added is 0.1-30% of the weight of the solid content of the polyimide, if too much is added, the heat stability of the negative composition is disrupted; if too little is added, it results in insufficient photosensitivity; thus the sufficient amount is 3-10%.
[0027] A suitable process for forming a polyimide pattern by using the negative photoresist composition of the present invention includes the steps as follows: (i) coating the negative photoresist composition onto an adequate substrate by spin coating or a like method; (ii) prebaking; (iii) exposing; (iv) development; and (v) post-curing to obtain a polyimide pattern. In the step (i), the adequate substrate can be a copper foil substrate, flexible copper clad laminate, silica substrate, glass, or ITO glass; and the like coating method can be roller coating, screen coating, curtain coating, dip coating, and spray coating, but is not limited thereto. The prebaking in step (ii) includes prebaking at 70-120° C. for several minutes to evaporate the solvents. The exposing in step (iii) includes exposing a prebaked substrate with actinic rays under a photomask, the actinic rays described above can be X-ray, electron beam ray, UV ray, visible light ray or another source of light that can supply actinic rays.
[0028] The exposed and coated substrate needs to undergo the development (iv) with an alkaline aqueous developing solution to obtain a photoresist pattern. The alkaline aqueous developing solution includes (but not limited thereto) an alkaline solution of an inorganic base (such as potassium hydroxide, and sodium hydroxide), a primary amine (such as ethylamine), a secondary amine (such as diethylamine), a tertiary amines (such as triethylamine), and a quaternary ammonium (such as tetramethylammonium hydroxide, abbreviated as TMAH), wherein the preferable developing solution should contain TMAH. The developing can be achieved by dipping, spraying, or coating or other methods. The photoresist pattern derived after developing is washed with deionized water, then subject to the post-curing (v) at 180-300° C. to remove the remaining solvents.
[0029] The present invention can be better understood through the following examples, which only serve the purpose of elucidation and are for limiting the scope of the present invention.
[0030] The formula for calculating the film residual rate is listed below:
Film residual rate (%)=[(the film thickness after post-curing)/(the film thickness after prebaking)]×100%
[0031] Chemicals:
bicyclo[2,2,2]oct-7-ene-2,3,5,6-tetracarboxylic dianhydride (B1317) bis(3,4-dicarboxyphenyl)ether dianhydride (ODPA) 3,3′,4,4′-benzophenone tetracarboxylic dianhydride (BTDA) 3,3′,4,4′-biphenyl tetracarboxylic dianhydride (BPDA) 3,5-diaminobenzoic acid (DABZ) 4,4′-Oxydianiline (ODA) 4,4′-bis(3-aminophenoxy)diphenyl sulfone (m-BAPS) 2,2-bis(4-(4-aminophenoxyl)phenyl)propane (BAPP) bisaminopropyltetramethyldisiloxane (Siloxane248) glycidyl methacrylate (GMA) N-methyl-2-pyrrolidone (NMP)
EXAMPLE 1
[0043] To 330 g of NMP in a 500-ml three-necked round bottom flask equipped with a mechanical stirrer and nitrogen inlet 11.41 g (75 mmol) of DABZ and 30.79 g (75 mmol) of BAPP were added and dissolved. The solution was placed into a 0° C. ice bath, followed by the addition of 24.5708 g (99 mmol) of B1317, and two hours of stirring, then the addition of 15.95 g (50 mmol) of BTDA prior to the continuation of stirring for another 4 hours; after that 70 g of xylene was added, the temperature was raised, azeotropic boiling of water and xylene occurred at 160° C. The temperature of the mixture was raised to 180° C. after xylene in the solution had completely escaped, and it was stirred for another 5 hours. A viscous and unmodified PI solution V-1 was obtained after cooling. In the next step, to 80 g of V-1 solution 1.09 g of GMA was added along with 0.08 g of hydroquinone as an inhibitor, which was then stirred at 100° C. for 12 hours to give a viscous PI solution PI-1. To the PI-1 solution 3.2 g of pentaerythritol triacrylate, 1.31 g of N-[3-(dimethylamino)propyl]methacrylamide (monomer having a tertiary amino group), and 1.6 g of photoinitiator, bis(2,4,6-trimethylbenzoyl)-phenylphosphineoxide, were added and well mix to obtain a photosensitizing polyimide PSPI-1. The PSPI-1 was evenly coated on an 1 OZ copper foil by a blade, prebaked for 5 minutes in a circulator oven at 120° C. to form a photosensitizing polyimide film having a thickness of about 20 μm. The copper foil coated with PSPI-1 and prebaked as described above was exposed with an unfiltered mercury arc lamp (its wavelength measured was between 250 nm and 400 nm) and a power of 1000 mJ/cm 2 . 3 wt % TMAH ethanol solution as the developing solution was used to develop the exposed film at 35° C. with ultrasonication for a developing time of 120 seconds, followed by washing with ethanol for 30 seconds, and drying with air dryer prior to a post-curing procedure in a circulator oven at 230° C. for 30 minutes. A polyimide pattern having a thickness of 18 μm was obtained. The pattern, which has been through the developing and post-curing procedures, has a residual film thickness of 90%. The pattern has a resolution of 30 μm in line width and line-span when it was observed via an optical microscopy.
EXAMPLE 2
[0044] To 80 g of the unmodified PI solution V-1 prepared in Example 1, 0.55 g of GMA was added along with 0.08 g of hydroquinone as an inhibitor, which was then stirred at 100° C. for 12 hours to give a viscous PI solution PI-2. To the PI-2 solution 3.2 g of pentaerythritol triacrylate, 1.97 g of N-[3-(dimethylamino)propyl]methacrylamide (monomer having a tertiary amino group), and 1.6 g of photoinitiator, bis(2,4,6-trimethylbenzoyl)-phenylphosphineoxide, were added and well mix to obtain a photosensitizing polyimide PSPI-2. The PSPI-2 was evenly coated on an 1 OZ copper foil by a blade, prebaked for 5 minutes in a circulator oven at 120° C. to form a photosensitizing polyimide film having a thickness of about 20 μm. The copper foil coated with PSPI-1 and prebaked as described above was exposed with an unfiltered mercury arc lamp (its wavelength measured was between 250 nm and 400 nm) and a power of 1000 mJ/cm 2 . 3 wt % TMAH ethanol solution as the developing solution was used to develop the exposed film at 35° C. with ultrasonication for a developing time of 30 seconds, followed by washing with ethanol for 30 seconds, and drying with air dryer prior to a post-curing procedure in a circulator oven at 230° C. for 30 minutes. A polyimide pattern having a thickness of 17 μm was obtained. The pattern, which has been through the developing and post-curing procedures, has a residual film thickness of 85%. The pattern has a resolution of 30 μm in line width and line-span when it was observed via an optical microscopy.
EXAMPLE 3
[0045] The PSPI-1 prepared in Example 1 was evenly coated on a releasing PET film by a blade, prebaked for 4 minutes in a circulator oven at 120° C. to form a photosensitizing polyimide film having a thickness of about 20 μm. The PET film coated with PSPI-1 and prebaked as described above was laminated on an 1 OZ copper foil by a pressing machine at a temperature of 120° C. and under a pressure 50 Kgf/mm 2 , and the PET film was stripped off to obtain a copper foil having a PSPI film, which was exposed with an unfiltered mercury arc lamp (its wavelength measured was between 250 nm and 400 nm) and a power of 1000 mJ/cm 2 . 3 wt % TMAH ethanol solution as the developing solution was used to develop the exposed film at 35° C. with ultrasonication for a developing time of 120 seconds, followed by washing with ethanol for 30 seconds, and drying with air dryer prior to a post-curing procedure in a circulator oven at 230° C. for 30 minutes. A polyimide pattern having a thickness of 18 μm was obtained. The pattern, which has been through the developing and post-curing procedures, has a residual film thickness of 90%.
COMPARATIVE EXAMPLE 1
[0046] To 80 g of the unmodified PI solution V-1 prepared in Example 1, 2.19 g of GMA was added along with 0.08 g of hydroquinone as an inhibitor, which was then stirred at 100° C. for 12 hours to give a viscous PI solution PIC-1. To the PIC-1 solution 3.2 g of pentaerythritol triacrylate, and 1.6 g of photoinitiator, bis(2,4,6-trimethylbenzoyl)-phenylphosphineoxide, were added and well mix to obtain a photosensitizing polyimide PSPIC-1. The PSPIC-1 was evenly coated on an 1 OZ copper foil by a blade, prebaked for 5 minutes in a circulator oven at 120° C. to form a photosensitizing polyimide film having a thickness of about 20 μm. The copper foil coated with PSPIC-1 and prebaked as described above was exposed with an unfiltered mercury arc lamp (its wavelength measured was between 250 nm and 400 nm) and a power of 1000 mJ/cm 2 . 3 wt % TMAH ethanol solution as the developing solution was used to develop the exposed film at 35° C. with ultrasonication. The development cannot succeed, i.e. the pattern cannot be developed clearly, after a developing time of 200 seconds and longer.
COMPARATIVE EXAMPLE 2
[0047] To 80 g of the PI-1 solution prepared in Example 1, 3.2 g of pentaerythritol triacrylate, and 1.6 g of photoinitiator, bis(2,4,6-trimethylbenzoyl)-phenylphosphineoxide, were added and well mix to obtain a photosensitizing polyimide PSPIC-2. The PSPIC-2 was evenly coated on an 1 OZ copper foil by a blade, prebaked for 5 minutes in a circulator oven at 120° C. to form a photosensitizing polyimide film having a thickness of about 20 μm. The copper foil coated with PSPIC-2 and prebaked as described above was exposed with an unfiltered mercury arc lamp (its wavelength measured was between 250 nm and 400 nm) and a power of 1000 mJ/cm 2 . 3 wt % TMAH ethanol solution as the developing solution was used to develop the exposed film at 35° C. with ultrasonication. The development cannot succeed, i.e. the pattern cannot be developed clearly, after a developing time of 200 seconds and longer.
COMPARATIVE EXAMPLE 3
[0048] To 80 g of the unmodified PI solution V-1 prepared in Example 1, 3.2 g of pentaerythritol triacrylate, 2.63 g of N-[3-(dimethylamino)propyl]methacrylamide (monomer having a tertiary amino group) and 1.6 g of photoinitiator, bis(2,4,6-trimethylbenzoyl)-phenylphosphineoxide, were added and well mix to obtain a photosensitizing polyimide PSPIC-3. The PSPIC-3 was evenly coated on an 1 OZ copper foil by a blade, prebaked for 5 minutes in a circulator oven at 120° C. to form a photosensitizing polyimide film having a thickness of about 20 μm. The copper foil coated with PSPIC-3 and prebaked as described above was exposed with an unfiltered mercury arc lamp (its wavelength measured was between 250 nm and 400 nm) and a power of 1000 mJ/cm 2 . 3 wt % TMAH ethanol solution as the developing solution was used to develop the exposed film at 35° C. with ultrasonication for a developing time of 90 seconds, followed by washing with ethanol for 30 seconds, and drying with air dryer prior to a post-curing procedure in a circulator oven at 230° C. for 30 minutes. A polyimide pattern having a thickness of 10 μm was obtained. The pattern, which has been through the developing and post-curing procedures, has a residual film thickness of 50%. The pattern has a resolution of 30 μm in line width and line-span when it was observed via an optical microscopy.
[0049] Table 1 lists the results from Examples 1 to Comparative Example 3.
TABLE 1 Ex. 1 Comp. Comp. Comp. and 3 Ex. 2 Ex. 1 Ex. 2 Ex. 3 Mole ratio between 0.5 0.25 1 0.5 0 GMA/—COOH in unmodified PI Mole ratio between 0.5 0.75 0 0 1 tertiary amino group/—COOH in unmodified PI Developing time (seconds) 120 90 >200 >200 <90 Residual film Thickness (%) 90 85 Cannot Cannot 50 develop develop
[0050] Table 2 lists the properties of the polyimide pattern prepared in Example 1.
TABLE 2 Properties Results Testing methods Tensile strength 10 kgf/mm 2 ASTM D882 Elongation 4.9% ASTM D882 Resolution <30 μm Electron Microscope Flexibility (MIT, R = 0.8) 485, 631, 670 IPC-TM-650(2.4.3) Adhesiveness 5 lb/in 180°, rough side (F2-WS) Thickness 20 μm 5% weight loss/Tg 319.6° C./224.6° C. TGA/TMA Coefficient of thermal 68.6 xpansion (ppm, 30-200° C.) DK/Df 3.7/0.023 Anti-soldering test passed (300° C. * 10 sec) | The present invention is directed to a negative photoresist composition which mainly is composed of a) a polyimide having pendant carboxyl groups, wherein a portion of the carboxyl groups reacted with glycidyl (meth)acrylate monomers to form covalent bonds. The photoresist composition further contains b) monomers having a tertiary amino group and a C═C double bond, which form ionic bonds with the remaining hydroxyl groups of the polyimide. The photoresist composition further contains c) a photoinitiator which is also called photosensitizer. The components a) to c) are all dissolved in a solvent. | 7 |
BACKGROUND OF INVENTION
1. Field of the Invention
The present invention relates to a frame arrangement for a vehicle, especially a commercial vehicle, and in particular to a frame arrangement which generally consists of two U or double-T shaped profiles, which being longitudinal beams are joined to each other at a design-determined spacing via cross beams into a so-called “ladder frame”, on which vehicle elements such as cargo surfaces, superstructures, brake mechanisms, running gears and so forth are arranged.
2. Technical Background
Heretofore, such ladder frame arrangements are generally configured such that the individual profiles are welded, riveted, or bolted together, so as to form a rigid vehicle frame. The problem with such frame arrangements, however, is that the torsion capability of this connection can be so greatly restricted that cracks may occur in the frame arrangement during operation of the vehicle, especially at welded seams and/or at transitions with especially pronounced differences in rigidity.
Thus, the problem of the present invention is to provide a frame arrangement for a vehicle, especially a commercial vehicle, which can safely absorb the forces acting on it and at the same time assure the required elasticity.
SUMMARY OF THE INVENTION
According to the invention, a frame arrangement is provided for a vehicle, especially a commercial vehicle, comprising a first frame element that extends essentially in the lengthwise direction of the vehicle, a fastening element that is arranged on the first frame element and configured to hold an axle guide, and a second frame element that is arranged essentially at right angles to the first frame element, the second frame element being fastened to the fastening element such that the second frame element surrounds the fastening element at least in some regions. The first frame element extends essentially in the lengthwise direction of the vehicle, i.e., essentially parallel to a lengthwise axis of the vehicle. Two frame elements are provided, each frame element being provided on one side of the vehicle (the right side and left side). The first frame element can be configured from two U-shaped profiles such that the base of the U-shaped profiles is turned toward each other, and the distal end regions point away from each other. The first frame element can also be configured from a double T-shaped profile. Of course, the first frame element can also be composed of any other desired cross sectional configuration. On the first frame element is provided a fastening element that is configured to support or attach an axle guide or trailing link. The fastening element thus advantageously has a bearing region, on which the axle guide is attached, preferably being able to twist or rotate. The second frame element is preferably arranged essentially at right angles or perpendicular to the first frame element. In other words, the second frame element is arranged such that it lies essentially transverse to the lengthwise direction of the vehicle. This arrangement includes in particular a frame arrangement in which the second frame element extends between two spaced-apart first frame elements. Consequently, a fastening region of the second frame element on the first frame element need not necessarily be arranged essentially at right angles to the latter, but instead can also make any desired angle with the first frame element.
The frame arrangement is particularly well adapted for use with vehicles which have an axle system with a pneumatic cushioning system. In these axle systems, basically all vertical forces arising are transmitted both by the fastening element and by the air spring bellows to the frame arrangement, especially the first frame element. The remaining forces, however, such as lateral forces, braking forces or stabilization torques, can only be transmitted by the fastening element to the frame arrangement, since the air spring bellows can generally transmit only vertically directed forces. For this reason, the connection system between a first frame element, fastening element, and axle guide is under very high strain and its design demands high strength. On the other hand, however, these components need to be configured as elastic as possible, so that the frame arrangement can twist in a given degree. Therefore, according to the invention, the second frame element is secured to the fastening element such that the second frame element surrounds the fastening element at least in some regions. This makes it possible to configure the regions on the fastening element that are especially endangered by the cross beam attachments and fastenings by means of advantageously expandable bolt connections or rivets so that all types of forces which occur can be distributed over broad areas and, at the same time, the frame arrangement remains elastic.
In a particular embodiment, the second frame element has a fastening segment of essentially U-shaped configuration, and the side segments forming the legs of the U are arranged on the fastening element. The fastening segment of the second frame element is advantageously U-shaped in cross section, and the side segments of the fastening segment are arranged essentially parallel to one dimension of the first frame element or parallel to the lengthwise direction of the vehicle. Thus, the second frame element surrounds the fastening element in the lengthwise direction of the vehicle, especially in the front. The side segments forming the legs of the U are arranged on or attached to welded wall regions of the fastening element.
In another particular embodiment, the second frame element is configured as one part or one piece, at least in the region of the fastening segment. This provides an especially stable second frame element in the region of the fastening segment, so that especially large forces can be absorbed by the second frame element.
In another preferred embodiment, the second frame element is configured with multiple parts or multiple pieces, preferably two pieces, at least in the region of the fastening segment. This makes it possible to configure the second frame element especially variably and flexibly, so that the fastening segment of the second frame element can be “adjusted” to different sizes of fastening element. Thanks to the multipart configuration of the second frame element in the region of the fastening segment, furthermore, an advantageous production simplification is made possible.
Preferably, the second frame element has a first end segment extending essentially perpendicular to the lengthwise dimension of the second frame element, being preferably arranged on the outside of the fastening element. The first end segment here corresponds in particular to the aforementioned second segment of the second frame element, so that it extends most advantageously parallel to the lengthwise direction of the vehicle. Preferably, the first end segment is arranged on or attached to the outside of the fastening element. The outside here is that side of the fastening element facing outward on the vehicle, or the vehicle's outside.
Moreover, the second frame element has a preferably essentially L-shaped second end segment, which is arranged on the inside of the fastening element. The inside of the fastening element here is in particular the side of the fastening element turned toward the inside of the vehicle. In a frame arrangement with two first frame elements, which are spaced apart and extend parallel to each other along the side regions of the vehicle, the insides of the fastening element are thus facing each other, whereas the outsides of the fastening element are turned away from each other. The essentially L-shaped configuration of the second end segment is especially advantageous in a configuration separate from the first end segment, i.e., for the aforementioned multipart or multipiece configuration of the second frame element at least in the region of the fastening segment. Of course, the second end segment can also have any other configuration different from the L-shape, as long as one region of the fastening element is surrounded by the combination of first and second end segment.
Preferably, the second end segment is secured by fasteners such as rivets or bolts to the fastening segment of the second frame element. In this way, the connection between second frame element and the second end segment remains elastic and can thus afford all necessary pliancy in the long term.
Also preferably, the second frame element is secured by fasteners such as bolts or rivets to the fastening element. The fasteners here are arranged basically transversely to the driving direction and configured so that the connection between the second frame element and the fastening element remains elastic and thus can afford all necessary pliancy in the long term. This is accomplished in particular by the natural elasticity of the fasteners. Moreover, this effect is intensified in that the fastening element and the second frame element are not rigidly secured to each other as with welding, but instead slight displacements with respect to each other are made possible due to the separate or multipart configuration.
Preferably, the second frame element is configured as a cross beam extending essentially transversely to the driving direction. Advantageously, the cross beam extends in a horizontal plane transversely to the driving direction, so that it is arranged between two opposite lying fastening elements of an axle. The cross beam in this case can be configured as a single part or single piece or as a multiple part or multiple piece. Due to the multipart or multi-piece configuration, it is especially advantageously ensured that different center to center spacings of the vehicle's longitudinal beams can be connected by the same cross beam system.
In another preferred embodiment, the frame arrangement furthermore has a reinforcement unit, which is formed from at least one reinforcement profile and arranged between the first and second frame element. The reinforcement unit can be made from an essentially one-piece profile, however, the reinforcement unit is preferably made as a multiple part, for example, such that the individual parts can be shifted and secured telescopically relative to each other. The reinforcement profile can have any given cross sectional configuration, however, the reinforcement profile is preferably U-shaped in cross section. The reinforcement unit extends essentially in a vertical plane and is arranged on or fastened to the second frame element spaced from the fastening segment. The fastening can advantageously occur by a bolt connection. The attachment or fastening of the reinforcement unit to the first frame element can be done directly on the latter. Advantageously, the first frame element has a reinforcement element, such as a web plate, at its region away from the fastening element, on which the reinforcement unit is fastened, preferably by a bolt connection. Due to the fastening by means of bolts or rivets, as mentioned above, one achieves an advantageously torsionable or elastic connection, which can resist the formation of cracks, as occur with welding.
The reinforcement unit is thus secured by a bolt and/or rivet connection to the first and second frame element.
Further advantages and features will emerge from the following description of preferred and sample embodiments of the invented frame arrangement with reference to the enclosed figures, written specification and claims, wherein individual elements or features of the embodiments can be combined to yield a new embodiment.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1 a - 1 c , include a front view, a top view, and a side view of a first sample embodiment of the invented frame arrangement.
FIGS. 2 a - 2 c , include a front view, a top view, and a side view of a second sample embodiment of the invented frame arrangement.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIGS. 1 a - 1 c shows a front view, a top view, and a side view of a sample embodiment of the invented frame arrangement for a vehicle, in particular, a commercial vehicle. The frame arrangement comprises a first frame element 2 , a fastening element 4 , and a second frame element 6 .
The first frame element 2 extends basically in the lengthwise direction of the vehicle or basically parallel to the vehicle's lengthwise axis X. Two first frame elements 2 are provided, which are spaced apart in relation to the vehicle's lengthwise axis X. The first frame element 2 is configured as a U or double T-shaped profile, so that this profile defines a bottom flange 8 and a top flange 10 . On the first frame element 2 , additional vehicle elements such as cargo surface, superstructures, brake mechanisms, and running gear components are arranged. Thus, the cargo surface and the superstructures are arranged accordingly on the top flange 10 , while the other running gear components are fastened to the bottom flange 8 . This is done by the fastening element 4 , which is secured to the first frame element 2 , especially to its bottom flange 8 . The fastening can be done by a welding or also, especially advantageously, by a bolting or rivet connection.
The fastening element 4 , in particular, serves to mount an axle guide or trailing link, which is arranged so that it can turn or pivot relative to the fastening element 4 . For this, the fastening element 4 has a bearing arrangement 12 .
The second frame element 6 is advantageously basically arranged at right angles, i.e., transverse to the vehicle's lengthwise axis X, relative to the first frame element 2 . Consequently, the second frame element 6 is configured in particular as a cross beam extending transversely to the driving direction, constituting a connection between the two spaced-apart first frame elements 2 . The second frame element 6 can be designed as a one-part element. Advantageously, however, it is designed as a multipart element, so as to allow for different distances of the first frame elements 2 from the center of the vehicle.
The second frame element 6 is secured on the fastening element 4 such that the second frame element 6 encloses the fastening element 4 at least in some regions. For this, the second frame element 6 has a fastening segment 14 , which is configured as basically a U-shape in cross section. The side segments forming the legs of the U are consequently arranged on side walls of the fastening element 4 . The side segments are formed by a first end segment 16 and a second end segment 18 . The first end segment 16 extends essentially perpendicular to the lengthwise dimension of the second frame element 6 , i.e., essentially parallel to the vehicle's lengthwise axis X and is preferably arranged on the outside of the fastening element 4 . Accordingly, the second end segment 18 is arranged on the inside of the fastening element 4 . In the embodiment shown, the second end segment 18 is basically configured in an L-shape. Of course, the second end segment 18 can have any other geometrical shape desired, as long as the second end segment 18 contributes to enclosing the fastening element 4 at least in some regions. Moreover, the first end segment 16 can likewise be arranged on the inside of the fastening element, so that the second end segment 18 consequently encloses the outside of the fastening element 4 . Preferably, the second end segment 18 is secured to the fastening segment 14 of the second frame element 6 by fasteners, which can be formed as a rivet connection 20 or bolt connection 22 (see FIGS. 2 a - 2 c ). The fastening of the second frame element 6 to the fastening element 4 is done by fasteners 24 , which can especially advantageously be configured as a bolt connection. The fasteners 24 advantageously extend essentially transverse to the vehicle's lengthwise axis X and form an elastic connection between the second frame element 6 and the fastening element 4 . The “elastic connection” here should be construed in particular in the sense that the connection formed by fastening element 4 and second frame element 6 enables a certain measure of torsion, as opposed to a welded connection familiar to the prior art.
The frame arrangement has a reinforcement unit 26 , which extends between the second frame element 6 and the first frame element 2 . The reinforcement unit 26 can have a one part or one piece configuration. Preferably, however, this is formed from a plurality of reinforcement profiles 28 , which can preferably move telescopically in one another and be secured in a particular position by means of a bolt connection 30 at a particular length. The reinforcement profiles 28 are advantageously configured as a U-profile in cross section. The reinforcement unit 26 is secured to the second frame element 6 , near the fastening segment 14 , by a bolt or rivet connection. At the opposite end, the reinforcement unit 26 is secured indirectly on the first frame element 2 . The securing in this place is done preferably indirectly by reinforcement element 32 provided on the top flange 10 and is likewise configured as a bolt or rivet connection. As a result of the bolt or rivet connection, as explained above, one achieves an advantageously elastic connection, so that some torsion ability of the frame arrangement is assured.
The frame arrangement has a reinforcement unit 26 , which extends between the second frame element 6 and the first frame element 2 . The reinforcement unit 26 can have a one part or one piece configuration. Preferably, however, this is formed from a plurality of reinforcement profiles 28 , which can preferably move telescopically in one another and be secured in a particular position by means of a bolt connection 30 at a particular length. The reinforcement profiles 28 are advantageously configured as a U-profile in cross section. The reinforcement unit 26 is secured to the second frame element 6 , near the fastening segment 14 , by a bolt or rivet connection. At the opposite end, the reinforcement unit 26 is secured indirectly on the first frame element 2 . The securing in this place is done preferably indirectly by a reinforcement element 32 provided on the top flange 10 and is likewise configured as a bolt or rivet connection. As a result of the bolt or rivet connection, as explained above, one achieves an advantageously elastic connection, so that some torsion ability of the frame arrangement is assured.
FIGS. 2 a - 2 c shows a second sample embodiment of the frame arrangement, wherein the elements identical to the first embodiment have been given the same reference symbols. In contrast with the first embodiment, the second frame element 6 is configured as a longitudinal profile. The fastening segment on the fastening element 4 is formed here by an essentially L-shaped first end segment 34 and an essentially L-shaped second end segment 36 , which are secured to the second frame element 6 by fasteners in the form of a bolt connection 22 .
Corresponding to the above embodiment, the first end segment 34 and the second end segment 36 are joined by fasteners 24 in the form of a bolt connection to the fastening element 4 so that a certain degree of torsion is provided between these two components.
Thus, frame arrangements are provided according to the invention that have a sufficient strength to absorb vertical as well as horizontal forces, and at the same time a necessary elasticity to provide for the desired torsion ability.
Preferably, the second frame element 6 and/or the fastening element 4 has, in the region where they are fastened or fixed to each other, projections or elevations 38 directed toward the other of the two elements, for making contact with the bearing surface of the other of the elements. Thus, in the present sample embodiment depicted, the elevations 38 on the first end segment 16 and the second end segment 18 of the second frame element 6 are configured so that they are oriented toward the fastening element 4 . Consequently, the contact surfaces between the second frame element 6 and the fastening element 4 are fashioned so that the contact between these elements is granted only immediately around the region where the fasteners 24 are situated. The other areas remain free of mutual contact and can be kept corrosion-free in the long term with the appropriate coating. Furthermore, the providing of elevations 38 accomplishes a stiffening effect for the elements, which can enhance the fatigue strength. Of course, the elevations 38 can be provided in addition or alternatively at appropriate positions of the fastening element 4 as well. Moreover, if the second frame element 6 has a multipart configuration, the connection sites between first end segment 16 and second end segment 18 can likewise have elevations 38 . The elevations 38 in this case can be configured in the region of the rivet connection 20 either in the first end segment 16 , or in the second end segment 18 , or in both end segments, such that only a point contact is provided between first end segment 16 and second end segment 18 .
In the foregoing description, it will be readily appreciated by those skilled in the art that modifications may be made to the invention without departing from the concepts disclosed herein. Such modifications are to be considered as included in the following claims, unless the claims by their language expressly state otherwise. | A frame arrangement for a vehicle comprises a first frame element extending a substantially lengthwise direction of a vehicle, a fastening element having sidewalls and operably coupled to the first frame element and configured to hold an axle guide, a second frame element extending substantially at right angles to the first frame element fastened to the fastening element such that the second frame element surrounds at least some region of the fastening element, and wherein the second frame element is substantially U-shaped and includes at least a pair of fastening segments forming legs of the U-shaped fastening segment. | 1 |
FIELD OF THE INVENTION
This invention relates generally to footwear and more particularly to a disposable pedicure sandal wherein the structure of the sandal maintains the toes in a separated position and also prevents the foot from engaging the ground or other surface over which the wearer walks.
BACKGROUND OF THE INVENTION
During the performance of a pedicure it is necessary to maintain the toes of the pedicure recipient in a spaced apart relation to provide easy access by the person performing the pedicure, as well as to prevent damage to any of the beautification treatment performed on the toes. Furthermore, toe separation is preferred for a period of time following the pedicure to prevent damage to the beautification treatment due to inadvertent contact between adjacent toes. Historically, the separation of toes during pedicure treatments has been achieved using wads of tissue, cotton and like random articles. In addition, various toe spacing devices specifically designed for use during the performance of a pedicure are commercially available. More recently, various pedicure sandals and sandal systems have been developed in an effort to enable individuals to walk around after a pedicure without damaging the treatment.
U.S. Pat. No. 4,017,987 discloses a pedicure sandal assembly to be worn following a pedicure, including a base portion having a foot connecting strap and spacers mounted thereon. The sandal disclosed in the '987 patent has significant limitations. First, because the sandal is for use after a pedicure it does not address the issue of providing toe separation during the pedicure. Second, the disclosed sandal has a relatively complicated structure, requiring the assembly of a plurality of individual components during manufacture. Consequently, employing the disclosed assembly as a disposable sandal would be cost prohibitive.
U.S. Pat. No. 4,207,880 discloses a pedicure aid incorporating individually attachable toe separator subassemblies for separating the toes during and after a pedicure, and wearable as a sandal to protect the toes from damage after a pedicure. However, like the sandal disclosed in the '987 patent, the multi-component sandal assembly disclosed in the '880 patent would be impractical for use as a disposable pedicure sandal.
U.S. Pat. Nos. 5,870,837 and 5,946,823 disclose further pedicure sandal designs wearable during and after the pedicure procedure. However, each of the disclosed assemblies suffer from one or more of the aforementioned limitations.
Accordingly, there is a well established need for a comfortable pedicure sandal wearable both during and after the performance of a pedicure, wherein the construction of the sandal is conducive to its manufacture as a cost-effective disposable article.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a pedicure sandal designed for maintaining separation of the wearer's toes during and after a pedicure treatment.
It is another object of the present invention to provide a pedicure sandal designed for effectively preventing damage to the treated toes while enabling the wearer to walk about comfortably following a pedicure treatment.
It is a further object of the present invention to provide a pedicure sandal having a construction conducive to its cost-effective manufacture as a disposable article.
It is yet a further object of the present invention to provide a pedicure sandal having foot supporting and toe separating means constructed from a contiguous area of material.
It is still another object of the present invention to provide a disposable pedicure sandal having a means for being easily removed without contacting the treated toe nails of the wearer.
These and other objects are achieved by the pedicure sandal of the present invention which includes a base portion 12 for supporting a human foot, and an integral toe separating portion 18 for engaging the toes and maintaining a desired toe spacing. In particular, integral toe separating portion 18 is selectively attached to the upper surface 14 of base portion 12 at strategically located attachment regions 20 to form individual toe-receiving loops 18 ( a-e ).
Each sandal is fabricated from a planar foot form 26 constructed from a spongy sheet of material for cushioning the foot of the wearer. Preferably, foot form 26 is provided with a single continuous cut along dotted line 23 to enable the partial detachment of a toe separating portion 18 from the base portion 12 . Alternatively, foot form 26 can be manufactured partially detached along dotted line 23 to enable the toe separating portion 18 to be easily detached at a later time without requiring a cutting or shearing apparatus.
The toe separating portion 18 is preferably sewn, or stitched, to upper surface 14 of base portion 12 . Alternatively, attachment can be achieved using mechanical fasteners, chemical adhesives, hook and pile attachments and heat seal means. Regardless of the attachment means employed, toe separating portion 18 is strategically secured to surface 14 to form individual toe receiving loops 18 ( a-e ) sized for comfortably engaging the individual toes 40 - 44 of the wearer's foot, and positioned for maintaining adequate separation of said toes.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a fully constructed pedicure sandal in accordance with the preferred embodiment of the present invention;
FIG. 2 is a top view of the pedicure footwear of the present invention in a partially fabricated state of construction, illustrating the location of the cut 23 made prior to attachment of the toe separating portion 18 to surface 14 ;
FIG. 3 is a perspective view of a partially fabricated pedicure footwear of the present invention, illustrating the partial detachment of the toe separating portion 18 from the initial foot form 26 of FIG. 3 during fabrication of the sandal;
FIG. 4 is a top view of the pedicure footwear of FIG. 1, illustrating the positioning of a phantom foot 30 therein.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
In use, the pedicure sandals of the present invention are provided in pairs and include left and right sandals for being worn on the respective left and right feet of the pedicure recipient. The left and right pedicure sandals are substantially the same except one is adapted for the left foot and one adapted for the right foot. Although the following description and illustrations are directed primarily to the right pedicure sandal for the purpose of clarity, it is to be understood that the discussion is equally relevant to the left pedicure sandal.
Referring now to FIG. 1, the pedicure sandal 10 of the present invention is set forth in a completely fabricated state. The pedicure sandal 10 includes a base portion 12 for supporting a human foot, and an integral toe separating portion 18 for engaging the toes and maintaining a desired toe spacing. In particular, integral toe separating portion 18 is selectively attached to the upper surface 14 of base portion 12 at strategically located attachment regions 20 to form individual toe-receiving loops 18 ( a-e ). As used herein, the term “integral” is intended to denote the unitary, or one piece, construction of the base and toe receiving portions.
Referring now to FIG. 2, each sandal is fabricated from a planar member 26 having a perimeter defined by edge 24 , and generally shaped for accommodating a human foot. In the preferred embodiment of the invention, a planar member 26 in the form of a human foot is cut from a larger area of spongy material (not shown) that provides for the cushioning of the foot when worn as a footwear. For example, the planar foot form 26 can be cut from a larger area of material using conventional die cutting equipment. The use of such equipment is well known in the art and further description is not provided herein. Although the use of an inexpensive sponge rubber material is preferred, the invention is not intended to be so limiting. It will be apparent to those skilled in the art of footwear manufacturing that the pedicure sandal of the present invention lends itself to fabrication using any of myriad flexible sheet-like materials, including flexible plastics and polymer foams. Furthermore, in lieu of the preferred single layer construction, foot form 26 can incorporate a multilayer construction.
Preferably, planar foot form 26 is provided with a single continuous cut (denoted by dotted line 23 ) to enable the partial detachment of toe separating portion 18 from base portion 12 . More specifically, the cut 23 enables toe separating portion 18 to be separated from base portion 12 along the perimeter of planar foot form 26 proximate end 15 , as clearly illustrated in FIG. 3 . Alternatively, planar member 26 can be manufactured partially detached along dotted line 23 to enable the toe separating portion 18 to be easily detached at a later time without requiring a cutting or shearing apparatus. In other words, in this alternate embodiment of the invention toe separating portion 18 is frangible along phantom line 23 . For example, partial detachment can be achieved by providing a series of perforations along phantom line 23 .
Referring now to FIGS. 1 and 4, the toe separating portion 18 is preferably sewn, or stitched, to upper surface 14 of base portion 12 . However, as will be apparent to those skilled in the art, myriad other means of attaching toe separating portion 18 to surface 14 are available. For example, attachment can be achieved using: mechanical fasteners, such as staples and rivets; chemical adhesives; hook and pile attachments, such as that sold under the trademark VELCRO; and heat seal means, to name just a few. Regardless of the attachment means employed, toe separating portion 18 is strategically secured to surface 14 to form individual toe receiving loops 18 ( a-e ) sized for comfortably engaging the individual toes 40 - 44 of the wearer's foot, and positioned for maintaining adequate separation of said toes.
Preferably, the strength of the resulting attachment regions 20 are adequate to prevent the inadvertent detachment of the toe separating portion at these regions during use. However, it is also preferable that these same attachment regions 20 enable the toe separating portion 18 to be detached by the wearer after the sandal has served its intended function, i.e., after the toe treatment has adequately dried or cured. Accordingly, it is preferred that the strength of the attachment regions 20 is such that the wearer can effectively detach the toe separating portion 18 from surface 14 at these regions by pulling upwards on portion 18 . The ability to detach the toe separating portion 18 from surface 14 in this manner results in a significant benefit of the present invention. Namely, the pedicure sandal can be removed and disposed of without requiring the wearer to slide her toes through loops 18 ( a-e ), thereby minimizing the potential for damaging the beautification treatment during removal of the sandal.
The novel structure of the present invention provides for significant advantages vis-a-vis known pedicure sandals. Most notably, the integration of the base portion 12 and the toe separation portion 18 into a single-bodied structure has provided for significant material and manufacturing cost reduction. As a result, the pedicure sandals of the present invention can be cost-effectively manufactured for disposable use.
While the preferred embodiments of the invention have been illustrated and described, it will be clear that the invention is not so limited. Numerous modifications, changes, variations, substitutions and equivalents will occur to those skilled in the art without departing from the spirit and scope of the present invention as described in the claims. For example, in lieu of cutting the planar foot forms 26 from sheets of material, planar foot forms 26 can be formed by employing any of a number of known molding technologies. | A pedicure sandal ( 10 ) fabricated from a spongy foot form includes a base portion ( 12 ) having an outer perimeter shaped to accommodate a human foot and an integrally connected toe separating portion ( 18 ) selectively attached ( 20 ) to the base portion to form a plurality of toe-receiving loops ( 18 a-e ) for engaging and separating the wearers toes. | 0 |
BACKGROUND OF THE INVENTION
1, Field of the Invention
This invention relates to a method of improving the mechanical properties of solder and brazing alloys of the type which have coarse, acicular and/or dendritic intermetallic phases and to the product thereof. More particularly, the method of the invention involves subjecting a melt of the alloy, while in a semi-solid state, to vigorous shearing or vibration at the solid-liquid interface. Upon solidification, the intermetallic phase or phases precipitate as fine, non-dendritic structures.
2. Prior Art
Some recently developed solder and brazing alloys have a microstructure containing coarse, acicular and/or dendritic intermetallic phases of relatively high hardness, and melting points higher than those of the matrix alloys. These intermetallic phases may form bulky dendritic or pointed structures which extend throughout the length of the soldered or brazed joint and adversely affect the mechanical properties which are potentially obtainable. The intermetallic phases may also be interconnected and thus may form a brittle bridge between the joined parts which also degrades creep strength, adherence and other important properties.
For example, governmental restrictions on the use of lead-based solders in potable water supply means have led to the development of solder compositions which generally contain tin and/or indium. It is well known that most tin and indium-based alloys contain one or more intermetallic phases after solidification from the molten state.
In some operations the dendritic intermetallic phase is larger than the gap between the pieces which are to be soldered or brazed. When this occurs, on application of the solder or braze wire the molten alloy which fills the gap is deficient (commonly referred to as macrosegregation), i.e., the intended composition of the solder or braze is different from that which actually flows into the gap by reason of the fact that the intermetallic phase or phases do not enter the gap which forms the joint.
The prior art has used extrusion of these alloys as a means of breaking up these intermetallic phases. Extrusion has been successful in breaking up interconnected structures, but it does not change the acicular and/or dendritic shape thereof.
The prior art has also resorted to the expedient of adding small amounts of sodium to aluminum--silicon alloys in order to alter the microstructure, but this modification has not been successful in eliminating the dendritic structure of the intermetallic phase therein.
Definite problems therefore exist with solder and brazing alloys which contain coarse, acicular and/or dendritic intermetallic phases, which makes it impossible to realize the potential improvement in properties which a hard, high melting point intermetallic phase would otherwise confer if present in finely divided, non-acicular and non-dendritic form.
SUMMARY OF THE INVENTION
It is a principal object of the invention to provide a method which solves the above problem by converting coarse, acicular and/or dendritic intermetallic phases into fine, non-acicular and non-dendritic structures which contribute positively to creep strength, wear resistance, flowability and adherence of such solder and brazing alloys.
It is a further object of the invention to provide a solder alloy containing uniformly dispersed non-acicular and non-dendritic intermetallic phases which have a particle size of about 1 to 25 microns.
According to the invention there is provided a method of improving the properties of solder and brazing alloys which contain coarse, acicular and/or dendritic intermetallic phases having a higher melting temperature than that of the matrix alloy, which comprises melting such a solder or brazing alloy at a temperature sufficient to melt the intermetallic phases, cooling the alloy to a semi-solid state, subjecting the semi-solid alloy to vigorous shearing and/or vibration at the solid-liquid interface while in the semi-solid state, and solidifying the alloy whereby to obtain a microstructure wherein the intermetallic phases are present as fine, non-acicular and non-dendritic structures.
The invention further provides a tin based alloy containing at least one uniformly dispersed non-acicular and non-dendritic intermetallic phase therein, this phase having a particle size of about 1 to 25 microns.
Exemplary solder and brazing alloys which contain one or more intermetallic phases having coarse, acicular and/or dendritic structures include the following systems:
silver--copper--phosphorus
silver--zinc
silver--tin
silver--copper--tin
tin--antimony
tin--copper
aluminum--silicon
magnesium--aluminum
indium--tin
bismuth--lead
All the above systems can be treated by the method of the invention to improve the mechanical properties thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
Reference is made to the accompanying drawings wherein:
FIG. 1 is a photomicrograph at 50 X of the cast microstructure of a tin--4% copper alloy; and
FIG. 2 is a photomicrograph of the microstructure at 50 X of a tin--4% copper alloy prepared in accordance with the method of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
In the silver--copper--phosphorus system the method of the present invention will refine the phosphide intermetallic phase. The following intermetallic phases will also be refined in accordance with the present invention:
silver--zincγ, ε(Ag 5 Zn 8 , Ag--Zn)
silver--tinγ, γ(Ag 3 Sn, Ag--Sn)
silver--copper--tinγ, ε(similar to Ag--Sn binary)
tin--antimony β, β'(Sb, Sn)
tin--copperη, η'(Cu 3 Sn, Cu 31 Sn 8 , Cu 20 Sn 6 )
aluminum--silicon Si
magnesium--aluminumβ,β'(Al 3 Mg 2 , Al 30 Mg 23 , Al 12 Mg 17 )
indium--tinβ(In 3 Sn, In Sn 4 )
bismuth--leadβ(Bi Pb 3 )
Referring to FIG. 1, which is a photomicrograph at 50 X of the tin--4% copper alloy which has been merely cast and solidified, it is evident that the intermetallic phase η precipitates in the form of relatively massive dendritic structures, some of which are interconnected. This phase has a melting temperature of 415° C. and hence will precipitate upon cooling of the molten alloy at temperatures substantially higher than the melting point of the matrix. The η phase changes crystal structure by solid state transformation to the η' phase at 186° C. but does not change in composition or morphology. When a soldering operation is later carried out, the intermetallic phases will melt only partially, thus forming a solder joint having a microstructure similar to that shown in FIG. 1, which is inherently weak, due to brittle bridging mechanisms, poor flowability and poor adherence.
FIG. 2, which is a photomicrograph at 50 X of the same alloy as that of FIG. 1 subjected to vigorous shearing in accordance with the invention, shows clearly the marked change in microstructure of the intermetallic phases. These phases are much finer in size and appear to have substantially no acicular or dendritic grains. The microstructure is relatively homogeneous throughout. In this form the intermetallic phases do not adversely affect mechanical properties but rather improve the creep strength, wear resistance, flowability, adherence and other properties. As pointed out above, since the intermetallic phases normally are not melted fully during the soldering or joining operation, the improved microstructure of FIG. 2 remains in the joint. Accordingly, no brittle bridging mechanisms are present.
The solder or brazing alloy of the invention also avoids the problem of macrosegregation described above, since the particle size of the intermetallic phase or phases is smaller than the gap between pieces to be joined, and these phases thus readily flow into the joint. The overall composition of the joint will thus be the same as that of the solder or braze wire. Improved mechanical properties of the joint can thus be attained.
Adherence is improved because no acicular or dendritic intermetallic phases project outwardly from the surfaces of the alloy.
Moreover, extrusion can be effected much more easily, and there is less wear and abrasion on the extrusion dies.
The term "vigorous shearing" as used herein should be understood to define an operation wherein the amount of shear is preferably greater than 1000%. The rate of shear preferably is greater than 0.5 to 1 mm/mm sec.
Shearing or vibration may be effected in any conventional manner and with conventional equipment. Either batch or continuous mixers may be used. Suitable equipment includes the Banbury Mixer, double blade mixer with sigma blades or overlapping blades, the Farrel Continuous Mixer (U.S. Pat. No. 3,154,808, issued 1969 to P. Hold et al), a centrifugal impact mixer, a so-called "motionless" mixer (such as the Ross Interfacial Surface Generator), and the like. Conventional ultrasonic agitation may also be used to ensure that the relatively fine grains of the intermetallic phase or phases remain uniformly dispersed in the semi-solid alloy, as well as to break up acicular and/or dendritic intermetallic phases. A suitable ultrasonic processor is sold under the trademark "Vibra-Cell", Models VC300/VC600, by Sonics and Materials, Inc.
EXAMPLE 1
A tin--copper alloy containing about 4% copper and balance tin aside from incidental impurities was heated to a temperature of 450° C. and held at temperature until completely molten. The alloy was then cooled until it reached a semi-solid state, at which time it was subjected to vigorous shearing in a Banbury type mixer and permitted to solidify. A sample was polished and etched in conventional manner, and a photomicrograph at 50 X was prepared, shown as FIG. 2. The intermetallic phases were uniformly dispersed, exhibited no sharp angularity and had an average grain size of 1 to 25 microns. Upon remelting at a temperature of about 375° C., and resolidification, the microstructure of FIG. 2 was substantially replicated.
Comparative tests were conducted, from which it was determined that tensile ductility was improved by 50%, and hardness was improved by 15%. It is well known in the art that when fine precipitates are present, the wear resistance and creep life will increase along with hardness.
EXAMPLE 2
A tin-silver alloy containing about 10% silver and balance tin aside from incidental impurities was melted at 310° C. and solidified, with half of the melt being subjected to agitation and the other half solidified without agitation. The matrix of the portion not subjected to agitation contained the intermetallic phase (Ag 3 Sn) in the form of large sharp dendrites similar to those shown in FIG. 1. The agitation of one portion was effected by shearing in a mixer and by ultrasonic vibration at 20KHz through an immersed piezoelectric crystal. The intermetallic phase was in fine particulate form with an average size of about 2 microns.
On remelting at 200° C. and pouring the same volume of each portion through a funnel, the unagitated portion took 50 seconds while the agitated portion took only 40 seconds. The improvement in fluidity was thus about 20%.
Modifications will be apparent to those skilled in the art and are considered to be within the scope of the invention. No limitations are to be inferred except as set forth in the appended claims. | A solder or brazing alloy having improved properties by reason of the presence of at least one uniformly dispersed non-acicular and non-dendritic intermetallic phase having a particle size of about 1 to 25 microns. A method of preparing the alloy comprises melting the alloy at a temperature sufficient to melt the intermetallic phase or phases, cooling to a semi-solid state, subjecting the semi-solid alloy to vigorous shearing and/or vibration at the solid-liquid interface, and solidifying the alloy. | 2 |
FIELD OF THE INVENTION
[0001] This invention relates generally to a connector for coaxial cable, such as the type used for cable TV transmission.
BACKGROUND OF THE INVENTION
[0002] Coaxial cable connectors that require crimping are associated with certain disadvantages. Crimping tools tend to wear out with repeated use, and crimping does not provide a satisfactory seal. A number of crimpless connectors have been developed which attempt to overcome these problems.
[0003] One type of crimpless connector receives a compression sleeve, which is first broken away from a plastic ring mounted on the connector, and then slid over the cable and finally inserted into the annular cavity between the inner wall of the connector and the jacket of the cable. A tool is used to push the compression sleeve fully into the connector with a snap engagement.
[0004] A problem with this connector is that it can be awkward to break the compression sleeve away from the connector and then thread it onto the cable, particularly when used in field installations where there may be adverse weather conditions. The compression sleeve can as well be inadvertently threaded onto the cable backwards, and it can also be dropped and lost.
[0005] An alternative crimpless connector has more recently been provided, which permits the cable to be secured to it by means of an integral grip bushing that surrounds an internal mandril defining an annular gap that may receive the jacket and braiding of an inserted cable. The bushing can thereafter be moved so as to squeeze and hold the braiding and jacket of the cable, forming a seal therewith. While this grip bushing cable connector has many advantages, it does not lend itself to use with coaxial cables of different thicknesses.
[0006] Within the cable television industry, RG6 and RG59 cable are the most prevalent standard. Common RG6 and RG59 cable has a central conductor, a dielectric insulator with a single aluminum foil cover, one layer of braided shield surrounding the foil covered dielectric insulator, and a plastic insulating jacket covering the braided shield.
[0007] In addition to common RG6 and RG59 cable, so called “Tri Shield” and “Quad Shield” versions are also increasingly widely used. Tri Shield cable has a second layer of foil which covers the braided shield. Quad Shield cable has both a second layer of foil and a second layer of braided shield over the second layer of foil.
[0008] As a result of the additional shielding layers, Tri Shield and Quad Shield RG6 and RG59 cables have overall thicknesses or diameters greater than that of common RG6 and RG59 cable. The standard diameter of common RG6 cable, for example, is 0.272 inches. For Tri Shield RG6 cable the standard diameter is 0.278 inches. For Quad Shield RG6 cable the standard diameter is 0.293 inches.
[0009] Due to the close tolerances required for the known grip bushing connectors, a single connector cannot properly accommodate and attach to all three thicknesses of cable. At least two different sizes of connector are required: one for common cable and Tri Shield cable, and a second one for Quad Shield cable.
[0010] This situation is inconvenient for installation technicians, and represents an undesirable cost to cable television companies and suppliers. Not only do two separate inventories of connectors have to be maintained, the two different sizes of connectors can be easily mixed up, leading to installation difficulties.
BRIEF SUMMARY OF THE INVENTION
[0011] The purpose of the present invention is to obviate or mitigate the disadvantages of known connectors for coaxial cable.
[0012] In accordance with the invention, a connector is provided for use with coaxial cables of the type having a central conductor, a dielectric insulator with at least one foil cover encasing the central conductor, and either one or more layers of braided shield around the dielectric insulator beneath an outer jacket.
[0013] The connector comprises an internal body, threaded nut means for interconnecting the connector to a mating connector or port, and an external body that includes a deformable inner collar, assembled together so as to resist subsequent disassembly. The connector is adapted to receive and to tightly hold and seal to cables of different thicknesses, such as common RG6 cable, Tri Shield RG6, and also Quad Shield RG6 cable.
[0014] The internal body is preferably in the form of a mandril that has a bore of a diameter to receive the dielectric insulator of the coaxial cable. The mandril has a sleeve with an end adapted to engage the cable beneath the jacket and the braided shield, whether the braided shield is in one layer, as in common RG6 cable and Tri Shield RG6 cable, or more layers, as in Quad Shield RG6 cable.
[0015] The threaded nut means is rotatably engaged to the mandril at the end which is remote from the sleeve end that is adapted to engage the cable.
[0016] The internal body also includes a cylindrical wall concentric to the sleeve of the mandril, defining an annular channel between them which is dimensioned to receive the jacket and the braided shield of an inserted cable, with a gap between the jacket and the wall. The size of the gap depends on the thickness of the cable, that is, the number of layers of braided shield.
[0017] The external body is preferably in the form of a gripping bushing that is mounted to the connector surrounding a portion of the mandril and concentric to it. At its free end it has a mouth of a diameter to receive the cable. The deformable inner collar of the external body is preferably positioned proximal to the mouth of the bushing.
[0018] The bushing is moveable from a first position in which the collar is remote from the annular gap, to a second position in which the collar is partially within the annular gap.
[0019] The connector can be attached to a cable by inserting the cable into the mouth of the bushing while it is in its first position, pushing the dielectric insulator of the cable into the bore of the mandril with the sleeve end thereof engaging beneath the braided shield and the jacket of the cable, and subsequently moving the bushing to its second position, thereby wedging the inner collar into the annular gap, where it becomes deformed to fill the annular gap and squeezes the braided shield and jacket of the cable, holding it tightly and sealing the connector to it.
[0020] Preferably, the connector includes an O ring retained in a groove on the mandril sealing it to the threaded nut means.
[0021] A single size of connector of the present invention can be used with common RG6 and Tri Shield RG6 cable, and also with Quad Shield RG6 cable. The invention thus eliminates the need to have two sizes of grip bushing connectors for these different sizes of cables.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] In order that the invention may be more clearly understood, reference will be made to the accompanying drawings which illustrate a preferred embodiment of the coaxial cable connector of the present invention, and in which:
[0023] [0023]FIG. 1 is a cross-sectional side view of a cable connector of the present invention;
[0024] [0024]FIG. 2 is a cross-sectional side view of the same connector as shown in FIG. 1, with a coaxial cable having been inserted therein;
[0025] [0025]FIG. 3 is a cross-sectional side view of the same connector as in FIG. 2, with the coaxial cable having been inserted further therein; and
[0026] [0026]FIG. 4 is a cross-sectional side view of the same connector as in FIG. 3, with the outer bushing of the connector having been moved from its original position, in which the connector can receive the coaxial cable, to its final position, in which the connector tightly holds the inserted coaxial cable and forms a seal therewith.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0027] In the drawings, the coaxial cable connector is denoted generally by reference number 10 . The cable is denoted by reference number 40 and is of a standard configuration comprising a central conductor 41 , a dielectric insulator 42 with a foil cover 43 , a braided shield 44 and a plastic jacket 45 .
[0028] The connector 10 comprises a mandril 11 , a nut member 12 , an O-ring 13 , a retainer 14 and a bushing 15 having an internal collar 35 . The O-ring 13 is made of a compressible, elastomeric material, such as rubber or plastic. The mandril 11 , nut member 12 , retainer 14 , and bushing 15 are all made of a rigid material, preferably metallic, such as brass. The collar 35 of the bushing 15 is made of a deformable material such as Delrin®, an acetal resin available from E.I. Dupont de Nemours and Company.
[0029] The mandril 11 is generally cylindrical having an enlarged base with a sleeve 17 extending therefrom. A flange 16 projects outwardly from the end of the enlarged base of the mandril 11 . The sleeve 17 has a tapered end 18 with a barb 19 . A bore 20 extends through the mandril 11 having a diameter to receive the dielectric 42 and its foil cover 43 and the conductor 41 .
[0030] The nut member 12 is mounted rotatably to the mandril 11 . The nut member 12 has an inwardly projecting flange 23 that engages the flange 16 of the mandril 11 to permit free rotation between the nut member 12 and the mandril. The nut member 12 is provided with internal threads 25 and hexagonal flats 24 .
[0031] The enlarged base 21 of the mandril 11 has an annular groove 28 in which sits the O-ring 13 . The O-ring 13 is of a size and dimension to seat in the annular groove 28 , and to contact sealingly with the flange 23 of the nut member 12 .
[0032] The retainer 14 is generally cylindrical and is fixedly mounted to the mandril 11 . The retainer 14 has a base 26 with a wall 27 extending therefrom. The base 26 has an internal diameter that allows it to be mounted to the enlarged base 21 of the mandril 11 and held securely by frictional engagement. The sleeve 17 of the mandril 11 and the wall 27 of the retainer 14 define an annular cavity 32 with a tapered entry 33 .
[0033] The bushing 15 is also cylindrical and has a mouth 31 at one end dimensioned to receive the coaxial cable 40 . The other end of the bushing 15 is adapted to be mounted to the retainer 14 with a close fitting slidable engagement.
[0034] The wall 27 of the retainer 14 has a stepped external surface such that a step 29 provides a positive stop for the bushing 15 to seat against when the bushing 15 has been activated to slide into its clamping position, as shown in FIG. 4.
[0035] The bushing 15 has an internal collar 35 made of a deformable plastic material, such as Delrin®. The collar 35 is generally cylindrical and is retained within the bushing proximal the mouth 31 . The outward facing rim 39 of the collar 35 is generally flat and seats at the mouth end of the bushing 15 . The inward facing rim 38 of the collar 35 has a tapered edge 36 . The collar 35 also has an external annular groove 37 .
[0036] The connector 10 is assembled by first mounting the O-ring 13 to the mandril 11 , then mounting the nut member 12 , and subsequently mounting the retainer 14 , which prevents the O-ring 13 and the nut member 12 from subsequent removal from the mandril 11 . The collar 35 is inserted into the bushing 15 . Finally, the bushing 15 is mounted to the retainer 14 as shown in FIG. 1.
[0037] In mounting the connector 10 to the coaxial cable 40 , the cable is first prepared by exposing a length of the central conductor 41 , and also stripping a further length of the dielectric 42 and foil-cover 43 . The braided shield 44 is cut slightly longer than the jacket 45 and is folded back over the edge thereof, as shown in FIG. 2.
[0038] Attachment of the connector 10 to the cable is shown in FIGS. 2-4. The prepared cable 40 is first inserted into the connector 10 such that the conductor 41 , the dielectric 42 and the foil 43 are received within the bore 20 of the mandril 11 . The tapered end 18 of the mandril slides beneath the braided shield 44 and the jacket 45 of the cable 40 . The barb 19 on the sleeve 17 of the mandril 11 resists subsequent removal of the cable 40 from the mandril 11 .
[0039] The trimmed end of the jacket 45 of the cable 40 and the folded back portion of the braided shield 44 are accommodated within the annular cavity 32 , entering at the tapered entry 33 .
[0040] When the cable 40 has been fully inserted into the connector 10 such that the conductor 41 extends into the nut member 12 , the connector is placed in a levered squeezing tool (not shown) by means of which the bushing 15 can be forced to slide over the retainer 14 .
[0041] As the bushing is moved the tapered edge 36 of the inner collar is inserted in the entry 33 of the annular cavity 32 , between the end 18 of the sleeve 17 of the mandril 11 and the end of the wall 27 of the retainer 14 . The inward facing rim 38 of the inner collar 35 is deformed to fill the gap 34 between the jacket 45 of the cable 40 and the retainer wall 27 , such that the cable 40 is clamped tightly and sealed by the connector 10 when the bushing 15 is squeezed fully onto the retainer 14 . The collar 35 deforms so as completely to fill the gap 34 between the cable 40 and the retainer wall 27 whether the cable has either one or two layers of braided shield 44 beneath the outer jacket 45 . The annular groove 37 of the collar 35 provides a region of weakness to promote the desired deformation of the collar 35 when the bushing 15 is compressed within the retainer 14 .
[0042] It will of course be appreciated that many variations are possible within the broad scope of the invention. For example, the retainer and mandril could be an integral body. The configuration of the connector and its component parts could also be modified. Means other than the threaded nut member could be substituted for engagement of the connector to an electronic device. The O-ring could be replaced with a different type of sealing means between the mandril and the nut member, and the placement of such O-ring or other sealing means could as well be altered. Moreover, the connector can be dimensioned for use with RG59 or other cables as well as RG6 cable. | A connector is provided for interconnecting a coaxial cable to an electrical device. The connector has an internal body and an external body which are assembled together, and which can be activated to clamp upon and seal to an inserted coaxial cable without disassembling the external body from the internal body. The external body includes a deformable inner collar that permits the connector to be attached and sealed to cables of varying thickness as are found on common single foil and braid cable, Tri Shield cable and Quad Shield cable. | 7 |
BACKGROUND OF THE INVENTION
[0001] This invention relates generally to refining apparatus. More particularly, the present invention relates to apparatus for shredding pulps.
[0002] Nowadays most of the refiners built are of twin disc design. The disadvantages of the twin disc refiner are the changing relative speed along the length of the refining zone, a relatively high idle running rating and problems with centering the rotor, particularly at low throughputs. Conical refiners are also used, whose most significant disadvantages are the poor pumping effect. This leads to throughput difficulties and, as a result, the need to enlarge the grooves in the refining zones, which reduces the edge length. The relative displacement of the knives when being set in relation to one another, the need for a sturdy design as a result of the bearing forces occurring, and the difficulties in changing the refiner plates can be considered further disadvantages.
[0003] Another type of refiner known is the so called cylindrical refiner, as described in U.S. Pat. No. 5,813,618, for example. With this type of refiner, some of the disadvantages mentioned can be avoided, however it is important to ensure that the knives are set evenly in order to guarantee the same gap and thus, the same refining conditions over the entire circumference and along the lengths of the axial refining zones.
SUMMARY OF THE INVENTION
[0004] The refiner according to the invention is thus characterized by the refining gap being set by wedges which are mounted on the stator and rotor and can be moved against each other. This causes an axial movement, of the same dimension over the entire circumference, to be converted into a corresponding radial movement. This principle guarantees that the knives have exactly the same setting.
[0005] An advantageous further development of the invention is characterized by an axially movable wedge carrier being provided.
[0006] A favorable further development of the invention is characterized by a radially movable wedge carrier being provided. This wedge carrier permits the corresponding axial movement to be converted into a radial movement, thus allowing the refining gap to be set exactly.
[0007] A favorable configuration of the invention is characterized by the gap being continuously adjustable between 0 and 2 mm, preferably between 0 and 1 mm, for example between 0 and 0.5 mm. Thus the refining gap can always be set in an optimum way to suit the properties of the pulp suspension.
[0008] An advantageous configuration of the invention is characterized by the gap being suitable for setting up to 15 mm. Thus, it is possible to avoid any damage to the refiner plates, also during start-up operations or if larger particles suddenly appear.
[0009] A favorable further development of the invention is characterized by the relative speed at the periphery being 15-35 m/sec., preferably 20-30 m/sec.
[0010] A favorable configuration of the invention is characterized by the rotor speed being between 400 and 1,800 rpm, preferably between 500 and 1,000 rpm.
[0011] An advantageous further development of a refiner with twin rotor according to the invention is characterized by two wedges being provided at the axially movable wedge carrier and whose inclined surfaces slide over the corresponding surfaces of the radially adjustable wedge carrier.
[0012] An advantageous configuration of the invention is characterized by the radially movable wedge carrier being divided into segments of a circle.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The present invention may be better understood and its numerous objects and advantages will become apparent to those skilled in the art by reference to the accompanying drawings in which:
[0014] [0014]FIG. 1 is a schematic view of a first embodiment of the refiner of the invention;
[0015] [0015]FIG. 2 is a schematic view of a second embodiment of the refiner of the invention;
[0016] [0016]FIG. 3 is a schematic view of a third embodiment of the refiner of the invention;
[0017] [0017]FIG. 4 is a schematic view of a fourth embodiment of the refiner of the invention;
[0018] [0018]FIG. 5 is a schematic view of a fifth embodiment of the refiner of the invention;
[0019] [0019]FIG. 6 is a schematic view of a sixth embodiment of the refiner of the invention;
[0020] [0020]FIG. 7 is a schematic view of a seventh embodiment of the refiner of the invention;
[0021] [0021]FIG. 8 is a schematic view of an eighth embodiment of the refiner of the invention;
[0022] [0022]FIG. 9 a side view of the refiner of FIG. 1;
[0023] [0023]FIG. 10 a cross section view of the rotor of FIG. 1;
[0024] [0024]FIG. 11 is a schematic view of the refiner of the invention having a central stock discharge;
[0025] [0025]FIG. 12 is a schematic view of the refiner of the invention having a central stock feed; and
[0026] [0026]FIG. 13 is an alternate embodiment of the refiner of FIG. 12.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0027] [0027]FIG. 1 shows a diagram of the setting mechanism at a refiner with a single cylinder. It comprises an axially movable wedge carrier 1 and a radially movable wedge carrier 2 on which a refiner plate 5 is mounted. The counter refiner plate 5 ′ is mounted on the rotor 4 . The energy from the setting mechanism is transferred along an inclined plane defined by the surface of the inclined face of wedge carrier 1 and the inclined face of wedge carrier 2 which are engaged at the inclined plane. If the wedge carrier 1 is now displaced axially, this results in radial displacement of the wedge carrier 2 due to the transfer of energy at the wedge. As a result, the gap 3 between the refiner plates 5 and 5 ′ can be set precisely.
[0028] [0028]FIG. 2 shows an analogous variant, but the rotor 4 here is of conical design. As a result, the refiner plates 5 and 5 ′ are also designed as parts of a cone.
[0029] [0029]FIG. 3 now shows a variant with a twin cylinder refiner.
[0030] Here, too the axial displacement of the wedge carrier 1 exerts force on the wedge carrier 1 which is displaced in radial direction as a result. In this case, it also sets the gap 3 between the refiner plates 5 of the stator and the refiner plates 5 ′ of the rotor. The refining gap in operations is between 0 and 2 mm, for example 0.5 mm. If larger impurities occur or also in the start-up phase of the machine, the gap can be opened to up to 16 mm.
[0031] [0031]FIG. 4 shows a further variant of the setting at a twin cylinder refiner. Instead of a single long wedge, there are two shorter wedge segments mounted on the wedge carrier 1 , each of which are approximately the same length as one of the cylindrical refining surfaces 5 ′. The wedge carrier 2 as counterpart beside these two cylindrical refining surfaces 5 ′ has inclined planes along which the wedge carrier 1 slides. It functions in the same way as in the preceding variants, where displacement of the wedge carrier 1 in axial direction in turn causes displacement of the wedge carrier 2 in radial direction. Since this movement is distributed between two wedge segment surfaces, this permits better and more even transfer of energy and thus, much more exact setting of the refining gap 3 between the refiner plates 5 and 5 ′.
[0032] [0032]FIGS. 5 and 6 show analogous configurations, with a conical rotor narrowing from the center outwards in FIG. 5 and a conical rotor widening from the center outwards in FIG. 6.
[0033] [0033]FIG. 7 shows a variant where the two wedge carriers converging on inclined planes are held together in the rotor. Here an axially movable wedge carrier 6 is provided that acts on a wedge carrier 7 which can be adjusted in radial direction and carries the refiner plates 9 ′ on the rotor. The stator 10 with the counter refiner plates 9 remains constant in this case, with the refining gap 8 being set between the refiner plates 9 and 9 ′.
[0034] [0034]FIG. 8 shows another variant of the configuration according to FIG. 7, where the refiner plates 9 and 9 ′ form a conical refining gap 8 .
[0035] [0035]FIG. 9 shows a view of a refiner according to the invention, where two sliding bolts 11 are shown, which help to move the wedge carrier 1 axially. The sliding bolts 11 are driven by a motor 13 from which the power is transferred by gears 12 . Due to these gears 12 , even adjustment of the sliding bolts 11 is also achieved. In addition, this illustration shows the feed 14 for the pulp suspension.
[0036] [0036]FIG. 10 contains a possible section through a rotor. The illustration shows the axially movable wedge carrier 1 , the radially movable wedge carrier 2 , the refining gap 3 formed by the refiner plates 5 and 5 ′, and the rotor 4 . The radially movable wedge carrier 2 slides here along the inclined plane 15 between wedge carrier 1 and wedge carrier 2 and is displaced radially along the edges of the triangular mountings 16 .
[0037] [0037]FIG. 11 shows a possible pulp feed variant to a twin cylinder refiner where the pulp is fed in through connections 14 and 14 and discharged again at the center through connection 18 . The pulp is deflected on both sides to the pulp feed channel by a disc 19 and further into the refining gap 3 . The same pulp routing is also possible with a twin cone which can be designed as a widening or a narrowing cone from the outer inlet to the center outlet.
[0038] [0038]FIG. 12 shows a possible pulp feed variant to a twin cylinder refiner with the refining gap setting according to the invention where the pulp is fed in centrally through pulp feed 14 and discharged again at both ends of the refiner through the outlets 18 and 18 ′. This illustration shows the variant according to FIG. 4 however the variant according to FIG. 3 can also be used.
[0039] [0039]FIG. 13 now shows a further variant using a combination of cylindrical and conical refining zones. The remaining elements correspond to those described under FIG. 12.
[0040] While preferred embodiments have been shown and described, various modifications and substitutions may be made thereto without departing from the spirit and scope of the invention. Accordingly, it is to be understood that the present invention has been described by way of illustration and not limitation. | A refiner for shredding pulps having refining surfaces provided on a rotor and a stator and which form a cylindrical or a conical refining gap. The refining gap is set by wedges which are mounted on the stator and rotor and can be moved against each other. | 3 |
The present invention concerns a liquid pumping system. Such a pumping system can work as a pump with various liquids. One application of such a pumping system can consist of a liquid gun, such as for water, which can project a liquid at a great distance and at a controllable rate, for example for watering plants or as a water cannon for use against fire or riots.
BACKGROUND OF THE INVENTION
In order to spray a liquid, use is generally made of centrifugal pumps which are coupled to a thermal engine. The drawback of such pumps is that they require a relatively high power. For example, a centrifugal pump which has an output of 1300 liters/minute at a pressure of 12 bar requires, for the thermal engine in which drives this, a power of 120 continental horsepower.
The aim of the invention is to propose a liquid pumping system which considerably reduces this power required for spraying said liquid, for example in a ratio of 8 to 10.
BRIEF SUMMARY OF INVENTION
To this end, a system for pumping a liquid according to the invention is characterised in that it consists of a chamber provided with an orifice for introducing, into the chamber, a liquid issuing from a source, an orifice for discharging the liquid out of the chamber and an orifice opposite to the orifice for discharging the liquid for introducing pressurised gas, each orifice being provided with a valve, the valves being controlled in a synchronized fashion according to two phases, a first so-called filling phase in which the valve associated with the introduction orifice is open whilst the other two valves are closed, thus enabling the chamber to be filled, and a second so-called expulsion phase in which the valve associated with introduction orifice is closed whilst the other two valves are open enabling pressurised gas to be introduced into the chamber through the introduction orifice, thus expelling the liquid contained in the chamber through the discharge orifice.
According to another characteristic of the invention, the chamber is provided with a vent opposite to the liquid introduction orifice, the vent itself being provided with a valve which opens and closes at the same time as the valve associated with the liquid introduction orifice.
According to another characteristic of the invention, alternative to the previous one, the chamber is provided with an orifice connected, via a valve, to a vacuum pump, the valve opening and closing at the same time as the valve associated with the liquid introduction orifice.
According to another characteristic of the invention, the valve associated with the introduction orifice is situated at the end of the chamber which is provided with the discharge orifice, the vent being situated at the other end.
According to another characteristic of the invention, it has means for detecting liquid levels in the said chamber, whose signals are supplied to a control unit designed to be able to control the opening and closing of the valves.
According to another characteristic of the invention, the chamber has, on the same side as its discharge orifice, a tapered part narrowing towards the discharge orifice.
The present invention also concerns a set of pumping system s in accordance with a pumping system as just described. According to the invention, it is characterised in that each system is controlled so that the discharge phases of each discharge system follow one after the other, and in that, whilst that of one system is current, filling phases are implemented in the other systems.
According to another characteristic of this set, the number n of discharge systems in the set is such that n times the discharge time correspond to a filling time.
BRIEF DESCRIPTION OF DRAWINGS
The characteristics of the invention mentioned above, as well as others, will emerge more clearly from a reading of the following description of an example embodiment, the description being given in relation to the accompanying drawings, amongst which:
FIG. 1 is a diagram showing a water pumping installation using a pumping system according to the invention,
FIG. 2 Is a diagram showing a water pumping installation using a pumping system according to a variant of the invention,
FIG. 3 shows a diagram of a body of a pumping system according to the invention in a particular embodiment.
FIG. 4 is a diagram of a set of pumping systems according to the invention, and
FIG. 5 is a diagram illustrating the functioning of a set in accordance with that of FIG. 4 .
DETAILED DESCRIPTION OF INVENTION
The installation depicted in FIG. 1 consists essentially of a pumping system according to the invention 100 , a liquid source 20 and a compression pump 30 intended to supply a gas at a relatively high pressure. For example, this gas is air.
The pumping system 100 which can be seen in this FIG. 1 consists essentially of a body forming in its interior a closed chamber 10 , for example but not necessarily cylindrical. The body 10 is provided with an orifice 11 intended for introducing liquid from the source 20 into the chamber of the body 10 and an orifice 12 for discharging, out of the chamber of the body 10 , the liquid which it contains. In the example embodiment depicted, the introduction orifice 11 and a discharge orifice 12 are situated in the lower part of the body 10 , which has a longitudinal axis which is vertical.
This body 10 is also provided with an orifice 13 which is opposite the orifice for discharging the said liquid 12 and which is designed to allow the introduction, into the chamber of the body 10 , of the gas under high pressure supplied by the compression pump 30 .
The body 10 is also provided with a vent 14 which is situated opposite the introduction orifice 12 .
The pumping system 100 also has a valve 15 placed on the pipe between the source 20 and the introduction orifice 11 , a valve 16 placed on the discharge orifice 12 , a valve 17 placed on the pipe between the pump 30 and the introduction orifice 13 and a valve 18 placed on the vent 14 .
The valves 15 to 18 are controlled in synchronism by means of a control unit 40 which also receives the signals on the one hand from a low-level detector 42 and on the other hand from a high-level detector 41 .
The pumping system 100 according to the invention functions as follows.
In a first phase referred to as the filling phase, the chamber of the body 10 is filled with a volume of liquid issuing from the source 20 . To do this, the introduction valve 15 and the valve of the vent 18 are opened, the gas introduction valve 13 and the discharge valve 16 for their part being closed. The liquid issuing from the source 20 enters by gravity into the chamber of the body 10 , via the introduction orifice 11 . Filling takes place until the liquid reaches the level of the high detector 41 , which transmits a signal to the control unit 40 , which triggers the closure of the valves 15 and 18 .
It will be noted that the vent 14 serves for the discharge of the air which is driven from the chamber of the body 10 by its filling with liquid.
In a second phase, referred to as the discharge phase, the gas introduction valve 17 is open, as is the discharge valve 16 . As a result, at the surface of the liquid which is opposite to the orifice 12 there is a gas pressure given by the pump 30 which has the effect of pressing on this surface and affording the discharge of the liquid through the orifice 12 . The liquid is expelled and sprayed in the form of a high-power jet.
It should be noted that, according to a preferred mode, the second phase commences immediately after the end of the first phase. Consequently the valves 16 and 17 open as soon as the valves 15 and 18 close.
It should be noted that the opening of the valves 16 can be slightly delayed with respect to the opening of the valves 17 .
When the liquid level corresponds to that of the low detector 42 , a signal is transmitted to the control unit 40 , which triggers the closure of the valves 16 and 17 . The control unit 40 can then once again trigger the first phase of the process.
With such a system, the consumed power necessary for its functioning was around 11 continental horsepower whereas, in order to have the same performance with regard to pressure and output of the water jet obtained, a power of 120 continental horsepower is necessary with a centrifugal pump.
In the example embodiment in FIG. 2, the vent 14 is replaced by an orifice 14 connected, via the valve 18 , to a suction pump 50 . The functioning is similar to that of the example embodiment depicted in FIG. 1, except that the liquid from the source 20 is no longer introduced by gravity but by producing a vacuum in the chamber of the body 10 by means of the suction pump 50 .
It should also be noted that the detectors 41 and 42 could be replaced by a pressure switch which, when the pressure in the body 10 reaches, whilst increasing, an upper limit valve, demands the closure of the valves 15 and 18 and which, when the pressure in the body 10 reaches, in falling, a lower limit value, demands the closure of the valves 16 and 17 .
FIG. 3 depicts a body 10 of a pumping system according to the invention with its introduction orifices 11 and 13 and its discharge orifice 12 a nd its vent (or suction orifice) 14 . This body 10 has the particularity of comprising, in its lower part, a tapered part 10 a narrowing towards the discharge orifice 12 . It was possible to show that this characteristic was advantageous for obtaining a fine atomisation at the end of the jet because of the mixing of water and gas which takes place at the end of discharge.
FIG. 4 depicts an installation with n pumping systems 101 to 10 n identical to the first embodiment depicted in F ig 1 . It should be noted however that the said systems could be identical to the second embodiment in FIG. 2 . In this FIG. 4, the valves 15 to 18 of each system 101 to 10 n have not been depicted for reasons of clarity in FIG. 4 .
The source 20 is therefore connected to the n introduction inlets 11 of the n pumping systems 101 to 10 n , via n respective valves 15 (see FIG. 1 ). Likewise, the compression pump 30 is connected to the n pressurised gas introduction inlets 13 of the n pumping systems 101 to 10 n , via n respective valves 17 (see FIG. 1) and the n discharge orifices 12 are connected to an outlet S. The vents 14 should be noted, which are also connected to respective valves 18 (see FIG. 1 ).
The control unit 40 controls each system 10 i (i being able to vary from 1 to n) as indicated above, that is to say according to two phases, a filling phase I and a discharge phase II, phases which are triggered and interrupted after reception of the level signals issuing from the detectors 41 and 42 of each system 10 i . FIG. 5 depicts how these phases I and II unfold over time for each pumping system of an installation which has three of them (n=3). It will be noted that, in this FIG. 5, that the duration of the filling phase I is greater than of the discharge phase II.
At time t 0 , the system 101 begins to fill, the system 102 discharges and the system 103 finishes filling. At time t 1 , the system 101 is still filling, the system 102 has finished discharging and is beginning to fill and the system 103 is beginning to discharge. At time t 2 , the system 101 finishes filling and begins to discharge, the system 102 is still filling and the system 103 has finished discharging and is beginning its filling.
It should be noted that the discharge phases II follow one after the other, and that, whilst that of one system is current, filling phases are implemented in the other systems. Advantageously, a number n of systems will be chosen such that n times the duration of the discharge phase II correspond to that of the filling phase I. This is because, in this case, the output at the outlet S is substantially constant. | A pumping system includes a chamber ( 10 ) having an intake orifice ( 11 ) for introducing liquid into said chamber ( 10 ). A discharge orifice ( 12 ) discharges the liquid from the chamber ( 10 ). Another orifice ( 13 ) receives pressurized gas. A valve is located at each of the orifices ( 11, 12, 13 ). The valves ( 15, 16, 17 ) are controlled in synchronization according to two phases. During the first phase the valve ( 15 ) opens at the intake orifice ( 11 ) while the other two valves ( 16 and 17 ) are closed, in order to fill the chamber ( 10 ). During a second phase the valve ( 15 ) associated with the intake orifice ( 11 ) is closed while the other two valves ( 16 and 17 ) are open, this enabling pressurized gas to be introduced into the chamber ( 10 ), thereby expelling the liquid in the chamber ( 10 ) through the discharge orifice ( 12 ). | 5 |
FIELD OF THE INVENTION
The present invention is generally related to power management techniques for computer chips. More particularly, the present invention is generally related to a power efficient flip-flop design.
BACKGROUND OF THE INVENTION
Flip-Flops are the basic elements in any sequential machine, such as a finite state machine, counter, register file, storage buffer, and the like. Accordingly, the design of the flip-flop has always been a focus of VLSI designers.
Conventional flip-flop designs are mainly focused on performance or area optimization, especially with respect to flip-flops used in microprocessors. However, with the ever increasing demand for power in microprocessor chips, it is imperative that the power efficiency of every circuit, including flip-flops, in a microprocessor chip be maximized. Accordingly, techniques have been developed for reducing power consumption in microprocessor chips, such as placing circuits, including conventional flip-flops, in a sleep mode.
Even when using techniques for reducing power consumption, current semiconductor technology development indicates that transistor off current (i.e., leakage current in each individual device and standby current in the whole chip) is comparable to the transistor “on” current, especially with respect to the 0.1 microns technology era. For example, even when circuits having flip-flops are functioning in an idle or sleep mode, a significant amount of power is dissipated through leakage paths.
SUMMARY OF THE INVENTION
In one respect, the present invention includes an exemplary method for minimizing power consumption by a circuit, such as a flip-flop. The method includes steps of providing power to a first latch in the circuit; capturing data in the first latch; transmitting data to a second latch in the circuit; and removing power from the first latch.
In another respect, the present invention includes an exemplary power efficient circuit having a first latch and a second latch connected to the first latch. The second latch is configured to receive data captured by the first latch. The circuit further includes a power switch connected to the first latch, and the power switch regulates power provided to the first latch. The first latch includes a high speed latch and the second latch includes a low leakage latch. The power switch minimizes power consumption by limiting the period of time power is provided to the high speed latch. Also, the power efficient circuit minimizes the leakage current generated by the high speed latch when power is not provided to the high speed latch by substantially eliminating a leakage path to ground using a virtual ground, the power switch and a decoupling device.
In comparison to known prior art, certain embodiments of the invention are capable of achieving certain aspects, such as providing an improved flip-flop design to minimize power consumption. Those skilled in the art will appreciate these and other aspects of various embodiments of the invention upon reading the following detailed description of a preferred embodiment with reference to the below-listed drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention is illustrated by way of example and not limitation in the accompanying figures in which like numeral references refer to like elements, and wherein:
FIG. 1 illustrates a schematic block diagram of an exemplary flip-flop employing principles of the present invention;
FIG. 2 illustrates an exemplary embodiment of the flip-flop shown in FIG. 1;
FIG. 3 illustrates a timing diagram for the flip-flop shown in FIG. 2;
FIG. 4 illustrates a flow chart of an exemplary method employing principles of the present invention;
FIG. 5 illustrates a register including flip-flops of the present invention; and
FIG. 6 illustrates a pipelined circuit including a flip-flop of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. However, it will be apparent to one of ordinary skill in the art that these specific details need not be used to practice the present invention. In other instances, well known structures, interfaces, and processes have not been shown in detail in order not to unnecessarily obscure the present invention.
FIG. 1 illustrates an exemplary embodiment of a flip-flop 100 employing principles of the present invention. The flip-flop 100 includes a high speed latch 10 connected to a low-leakage latch 20 . Data is received by the high speed latch 10 on a data input 12 and transmitted, for example, to a circuit connected to the flip-flop 100 through a data output 14 of the high speed latch 10 . The high speed latch 10 may be a low threshold (i.e., low Vt) latch implemented using pseudo-NMOS, domino logic, dynamic logic, and the like. A low threshold latch, when compared to a high threshold latch (i.e., high Vt), typically provides more current at the same driving voltage than a high threshold latch. This generally increases the speed of the low threshold latch, when compared to a high threshold latch. However, low threshold devices generate leakage current (i.e., a typical characteristic of low threshold devices), which increases power consumption. The low leakage latch 20 may include a high threshold latch, which may be slower than a low threshold latch. However, a high threshold latch generally produces minimal leakage current (i.e., a typical characteristic of high threshold devices), which minimizes power consumption.
The high speed latch 10 is connected to a virtual ground 30 , rather than a real ground. The virtual ground may include a metal strip, and the like connected to one or more low threshold devices. The virtual ground 30 is connected to a real ground through a power switch 40 , which may be an external, low-resistance, high threshold (i.e., high Vt), power switch. The power switch 40 regulates power provided to the high speed latch 10 , by connecting and disconnecting a path to the real ground. When the power switch 40 is activated (i.e., closed), the high speed latch 10 receives power and data on the data input 12 is captured. Otherwise, the power switch 40 is deactivated (i.e., open), and the high speed latch 10 is placed in a standby mode (i.e., power is not provided to the high speed latch 10 ). When the power switch is deactivated, a path to the real ground is disconnected. Therefore, leakage current from the high speed latch is substantially eliminated, and power is conserved.
A capture signal 45 may be used to control the power switch 40 . For example, the capture signal 45 may include a pulse that turns on the power switch 40 , causing power to be provided to the high speed latch 10 for the duration of the pulse (e.g., for the duration the pulse is active “high”). For example, data is captured by the high speed latch 10 when a short pulse driving the power switch attached to the virtual ground becomes active (e.g., “high”). After the pulse returns to inactive (e.g., “low”), the high speed latch 10 is disconnected from the real ground by the power switch 40 for preventing a possible leakage path in the standby mode.
When data is captured by the high speed latch 10 , the data is also simultaneously transmitted to the low leakage latch 20 to retain the data when power is not provided to the high speed latch 10 . The low leakage latch 20 is connected to the data output 14 through a release latch 50 . The release latch 50 may include complementary transmission gates for allowing a full swing signal to pass through to the data output 14 . A full swing signal includes a signal swing from 0 to VDD. If only one NMOSFET is used, rather than a complimentary gate design, a smaller swing signal is produced, which affects signal integrity. When the release latch 50 is activated by the release signal 55 , data retained by the low leakage latch 20 is transmitted to the data output 14 of the flip-flop 100 from the low leakage latch 20 . The low leakage latch 20 may be continually powered, but minimal leakage current is produced by a low leakage (high threshold) switch. The release latch 50 and the low leakage latch 20 function as data retainers. Accordingly, small transistor sizes that consume less power may be used for latches 20 and 50 .
The release signal 55 and the capture signal 45 may be complimentary. Therefore, after data is captured by the high speed latch 10 , it would be immediately released to the data output 14 by the low leakage latch 20 . Also, the capture signal 45 and the release signal 55 may be derived from a clock signal used by the flip-flop 100 .
FIG. 2 illustrates an exemplary embodiment of the flip-flop 100 , shown in FIG. 1 . FIG. 2 shows a master/slave flip-flop 200 , including a master latch 210 , a slave latch 211 and a low leakage latch 212 . Master latch 210 (e.g., a high Vt and low leakage latch) is a master data latch with low leakage properties. Slave latch 211 (e.g., a low Vt and high leakage latch) is a slave data latch with high speed properties. Master latch 210 and slave latch 211 form the high speed flip-flop 200 . However, the high speed flip-flop 200 generally has a high leakage current.
To minimize leakage from the slave latch 211 , inverters 221 and 220 in the slave latch 211 are connected to a virtual ground 230 , which is connected to a real ground through a power switch 214 . The power switch 214 , which is activated by a capture signal 235 , may include a large transistor, because the power switch 214 may have a low switching resistance requirement. Also, the power switch 214 may be shared by multiple flip-flops to reduce the area overhead. A PMOS de-coupling device 215 may be connected to the virtual ground 230 for discharging electrons caused by coupling when the virtual ground 230 is disconnected from the real ground. For example, when the power switch 214 turns off, coupling may cause a malfunction of the pull down devices in the power switch 214 . The decoupling device 215 functions to discharge retained electrons, thereby minimizing the coupling effect.
Data received by the master latch 210 on a data input D of the flip-flop 200 is transmitted to the slave latch 211 when the capture signal 235 activates the power switch 214 . The data is simultaneously transmitted to the low leakage latch 212 , and then the power switch 214 removes power from the slave latch 211 in response to the capture signal deactivating the power switch 214 . Therefore, the low leakage latch 212 retains the data when power is removed from the slave latch 211 .
The low leakage latch 212 is connected to the data output Q of the flip-flop 200 through a release latch 213 , which is activated by a release signal 240 . When the release latch 214 is activated by the release signal 240 , data retained by the low leakage latch 212 is transmitted to the data output Q of the flip-flop 200 from the low leakage latch 212 . The low leakage latch 212 may be continually powered, but minimal leakage current is produced by a low leakage switch. The release latch 214 and the low leakage latch 212 function as data retainers, and small transistors that consume less power may be used for these latches.
The release signal 240 and the capture signal 235 may be complimentary. Therefore, after data is captured by the slave latch 211 , the data is immediately released to the data output Q by the low leakage latch 212 . Also, the capture signal 235 and the release signal 240 may be derived from a clock signal CLK used by the flip-flop 200 .
FIG. 3 illustrates a timing diagram 300 showing a timing sequence of the flip-flop 200 , LO shown in FIG. 2 . The capture signal 235 may include a short pulse derived from the clock signal CLK. The pulse width (t pulse ) of the capture signal 235 may be wide enough (e.g., one tenth of the period of CLK) for the data to be captured by the slave latch 211 and transmitted to the low leakage latch 212 for storing the data. The slave latch 211 receives power for the duration of the pulse of the capture signal 235 . Therefore, power is conserved by limiting the width of the pulse of the capture signal 235 . The power saving time shown in FIG. 3 indicates the period of time that the power switch 214 removes power from the slave latch 211 to minimize power consumption by the slave latch 211 .
The release signal 240 , which releases the data stored in the low leakage latch 212 to the output Q, preferably is a complementary signal of the capture signal 235 . D and Q illustrate the timing of data received on the input D of the flip-flop 200 and data output on the output Q of the flip-flop 200 . When incoming data arrives at the input D of the flip-flop 200 , the incoming data needs to satisfy the set up time (t setup ) of the master latch 210 before the positive edge of the clock signal CLK arrives. Accordingly, a transition (e.g., from “0” to “1” or vice versa) of the incoming data on the input D should be completed before the positive edge of the clock signal is received. The data stored in the low leakage latch is transmitted from the output Q after a delay time(t d ) from the clock edge.
The set up time (t setup ) includes the length of time it takes the master latch 210 to stabilize the input transition. The set up time is determined by the propagation delay of the master latch 210 and is usually not as critical as an output delay of the master latch 210 . Therefore, high Vt (i.e., slower speed) devices may be used in the master stage in order to reduce the complexity of the design of the flip-flop 200 . However, when using the flip-flop 200 in a high speed, finite, state machine, both setup time and output delay of the flip-flop 200 may be equally important. Therefore, for a high speed, finite, state machine or other high speed uses of the flip-flop 200 , the master latch 210 may include low Vt (i.e., higher speed) devices to improve performance.
FIG. 4 illustrates an exemplary method employing principles of the present invention. In step 410 , data is received by a flip-flop having a high speed latch (e.g., flip-flop 200 ). In step 420 , power is provided to the high speed latch. In step 430 , the high speed latch captures the data. In step 440 , the data is transmitted to a low leakage latch connected to the high speed latch. In step 450 , power provided to the high speed latch is removed. In step 460 , the data is transmitted from the low leakage latch to the output of the flip-flop. It will be apparent to one of ordinary skill in the art that steps 420 , 430 and 440 may be executed simultaneously and steps 450 and 460 may be executed simultaneously.
Flip-flops 100 and 200 may be used for a variety of applications, including a finite state machine, counter, register file, storage buffer, and the like. For example, FIG. 5 illustrates a flip-flop employing principles of the present invention utilized in a 64-bit register 500 . Register 500 includes flip-flops 510 , which may include flip-flops 100 or 200 shown in FIGS. 1 and 2 respectively, connected to a virtual ground 520 . The virtual ground is connected to a power switch 530 , which may include a large size FET, for controlling power applied to a high speed latch in each of the flip-flops 510 and for minimizing leakage current. A single power switch 530 may be used or one power switch for each register may be included in the register 500 . Similar to the power switches 40 and 214 in flip-flops 100 and 200 respectively, the power switch 530 may provide power to a high speed latch in each of the flip-flops 500 temporarily. A capture signal 540 may be used to activate/deactivate the power switch 530 .
Another example of an application for the flip-flops of the present invention is shown in FIG. 6 and described in co-pending U.S. patent application serial no. (Unassigned) (attorney docket No. 10013827), entitled “Power Management For A Pipelined Circuit”, which is herein incorporated by reference. FIG. 6 illustrates a pipelined control circuit 600 , including a combinational circuit 610 connected to a flip-flop 620 . Flip-flop 620 may be configured similarly to flip-flop 100 or 200 . The combinational circuit 610 and the flip-flop 620 include low threshold, high speed devices that tend to produce leakage current. A power switch 640 is connected to the low threshold devices through a virtual ground 630 for controlling power provided to the low threshold devices and for minimizing leakage current. Instead of capture and release signals, data capture and data output is controlled by a power down signal 645 . The power down signal 645 controls whether the pipelined control circuit 600 is in a standby mode or an active mode. In standby mode, the power switch 640 functions to remove power from the low threshold devices, and power is conserved. In active mode, the low threshold devices receive power.
While this invention has been described in conjunction with the specific embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. There are changes that may be made without departing from the spirit and scope of the invention. Furthermore, it will be apparent to one of ordinary skill in the art that flip-flop types, other than a master-slave flip-flop, may be configured to employ the power saving techniques of the present invention. Also, it will be apparent to one of ordinary skill in the art that the flip-flops of the present invention may be used in applications other than shown in FIGS. 5-6. | A power efficient flip-flop includes a power switch regulating power supplied to a high speed latch in the flip-flop. When the power switch is activated, causing the high speed latch to receive power, the high speed latch captures data received by the flip-flop. The captured data is propagated by the high speed latch to the output of the flip-flop. Simultaneously, the high speed latch transmits the data to a low leakage latch connected to the high speed latch. Then, power is removed from the high speed latch, and the data retained in the low leakage static latch is now released to the output of the flip-flop. The power efficient flip-flop minimizes leakage current generated by the high speed latch by removing a path to ground when power is not provided to the high speed latch. A decoupling device is connected to the power switch to substantially eliminate a coupling effect. | 7 |
PRIORITY CLAIM
[0001] Applicant claims the benefit of the filing date of Feb. 23, 2006 of its U.S. provisional patent application Ser. No. 60/776,116, expressly incorporated in its entirety herein.
FIELD OF THE INVENTION
[0002] This invention relates to manmade islands and more particularly to components of and methods for constructing manmade islands, and to structures and processes for enhancing existing island and land features.
BACKGROUND OF THE INVENTION
[0003] The available quantity of beachfront or waterfront properties in desirable geographic locations is dwindling. Increasing development reduces the sites available for commercial, residential or resort facilities. One potential solution is the creation of manmade islands or terrain, or enhancing current land terrain.
[0004] One prior system of building artificial islands includes dredging and reclamation processes which involve collecting sand from the sea bottom and blowing the collected sand into a solid formation until an island is formed. By mixing crushed rock with the sand, the process and integrity of the island may be enhanced. The sand is then compacted to meet construction standards.
[0005] This dredging process is met with resistance in some parts of the world as being environmentally damaging. The process requires large dredging ships for long periods of time.
[0006] In addition, the natural currents of water constantly erode the unprotected sand islands. The sand islands do not offer an attachment mechanism or sound base for adding features such as buildings.
[0007] The sand islands do not offer hard edges or options in beach profiles. The standard, natural profile sloped beach is typically the only option available with the dredging process. The dredging system does not offer the option to present unique characteristics of the island. Nor do the prior techniques offer structures defining and housing water front facilities.
[0008] There is a need to produce manmade or artificial islands in areas of the sea, or in lakes or other bodies of water, or to enhance existing land or island features. Such islands and enhancements are desired to provide a sound base on which decorative, aesthetic or inhabitable features or facilities can be placed on a permanent basis and without susceptibility to erosion or other weather or natural occurrences.
SUMMARY OF THE INVENTION
[0009] The manmade island components and methods according to the invention provide solutions to these circumstances. They provide the opportunity to create exciting, adventurous details on manmade island structures. Coves, atolls, caves, caverns, lagoons, pools, protected harbors, protected wave pool harbors and more are all possible with the components and methods of the present invention.
[0010] In more detail, the present invention contemplates a manmade island structure comprising, initially, artificial or manmade “formations”, such as a reef formation, fabricated on dry land and transported to sea, lake or other water body site for installation and formation of a formation for defining a structure in a above the water body according to a predetermined design.
[0011] The formations are constructed in multiple components or elements, each comprising a part of an entire formation, using typical concrete foundation wall forms where the wall forms are removed once the cement begins to set, and forming cementitious or synthetic facades as a supported shell thereon. A second option is free-forming the formations by placing rebar or other material into the desired shape of the reef and applying the cement mix pneumatically. As the concrete of each reef form cures, each structure will be loaded onto a barge for transportation to the installation site.
[0012] At the island-side of each formation, a concrete foot is provided as an anchoring feature. The weight of the island actually bears down on this area of the formation in order to hold the formation in place.
[0013] One embodiment of the formations defines a sloped beach area accomplished by a sloping concrete beach floor as will be described. Open sand chambers within the formation may also form the natural sloping effect to provide for beach areas while holding the sand in place. The primary materials used in construction are reinforcing steel, concrete, fibers in the concrete mix, prefabricated artificial rock systems and various protective coatings, including but not limited to epoxy, urethane and polyester coatings.
[0014] It will be appreciated that the formations are designed to provide and define many attractive structures and features typically associated with a water body, island or shoreline. Entire coves, atolls, caves, caverns, lagoons, pools, protected harbors, protected wave pool harbors and other facilities and aesthetics can be provided according to the invention herein.
[0015] This invention can be used to extend, enhance or enlarge existing natural islands as well as establishing new islands where no exist.
[0016] The invention can also be used to construct traditional types of buildings at sea that display different architecture, design and themes.
[0017] These and other objectives and advantages of the invention will be readily appreciated from the foregoing, and from the following description and drawings, in which:
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIG. 1 is an elevational view in partial cross-section illustrating a beach entry reef formation according to the invention;
[0019] FIGS. 2 is a elevational view in partial cross-section illustrating a replaceable coral wave break reef formation according to the invention;
[0020] FIG. 3 is an elevational view in partial cross-section illustrating a cliff rock from sea floor formation according to the invention;
[0021] FIG. 4 is an elevational view in partial cross-section illustrating a cliff walk formation according to the invention;
[0022] FIG. 5 is an elevational view in partial cross-section illustrating a spire island formation according to the invention;
[0023] FIG. 6 is an elevational view in partial cross-section illustrating a coast line undercut formation according to the invention;
[0024] FIG. 7 is an elevational view in partial cross-section illustrating a protected beach walk formation according to the invention;
[0025] FIG. 8 is an elevational view in partial cross-section illustrating an elevated sunbathing platform formation according to the invention;
[0026] FIG. 9 is an elevational view in partial cross-section illustrating an erosion protection formation according to the invention;
[0027] FIG. 10 is an elevational view in partial cross-section illustrating an animal and fish containment formation according to the invention;
[0028] FIG. 11 is an elevational view in partial cross-section illustrating a beach stabilization formation according to the invention;
[0029] FIGS. 12A and 12B illustrate in partial cross-section two respective book end reef formations according to the invention;
[0030] FIG. 13 is an elevational view in partial cross-section illustrating a formation comprising a center support column structure according to the invention;
[0031] FIG. 14 is an elevational view in partial cross-section illustrating a slab coral formation according to the invention;
[0032] FIG. 15 is an elevational view in partial cross-section illustrating an architectural formation according to the invention and further illustrates a structural foundation for a variety of themed finishes; and
[0033] FIG. 16 is an overhead or plan view illustrating an entire island or atoll according to the invention.
DETAILED DESCRIPTION
[0034] It will be appreciated that the invention contemplates the use of a plurality of complimentary formation components or elements joined or associated with one another to provide a structural formation for a facility beneath a water body or above a water body. In many variations, a “formation” component or element as that term is used herein, comprises an internal structure or frame supporting a shell comprising a cementitious or synthetic material preferably formed to have or to emulate a reef or rock-like appearance and preferably used with other complimentary formation elements to define a beach, island, cliff, platform housing or other architectural structures as will be described.
[0035] One or more complimentary formation elements are preferably preformed, then transported and placed at an installation site.
[0036] Details of the invention are perhaps best seen in the figures representing and illustrating numerous embodiments, combinations and uses of the reef formation described herein.
[0037] Turning now to the drawings, there is shown in FIG. 1 an illustrative cross-section of a beach entry reef formation 10 , with one component 11 thereof shown in cross-section. Element 11 is comprised of a base member 12 , a plurality of upright frame members 13 , 14 and 15 , an upper surface 16 and a natural finish or facade 17 below the water line WL. It will be appreciated that water lines shown in each of the following figures are designated as WL for clarity and brevity. Water line WL is the surface of a water body 18 which may be the sea, a lake or other water body having a floor 19 .
[0038] It will be appreciated that a plurality of similar or complimentary elements 11 can be interconnected operationally to form an entire beach entry area. Sand is disposed over the upper surface 16 of the elements 11 so as to comprise a beach of sloped configuration, both above and below the water line WL.
[0039] It will be further appreciated that, in this configuration as shown in FIG. 1 , the upright frame members 13 , 14 , 15 , which may also comprise walls or structural beams which define chambers therebetween, and those chambers are filled with a ballast material, such as at 23 , and which may be comprised of pebbles, rocks, cementitious materials or other materials suitable for ballast in holding the elements 11 in place.
[0040] It will also be appreciated that base 12 has an inward or land projecting extension or foot 24 , which is also covered by sand and which serves to facilitate the anchoring of the elements 11 and thus the entire formation 10 in an appropriate position with respect to the water body 18 .
[0041] In addition, it will be appreciated that the facade or finish 17 may be formed of any suitable material, such as a synthetic material which is finished to take on or emulate the aesthetic appearance of a coral reef, for example. Accordingly, and while the elements 11 are sunk generally slightly below the floor 19 of the water body 18 , the facade 17 extends both below and above, and presents from the viewpoint of the water body a reef-like configuration.
[0042] Finally, it will be appreciated that pilings, such as illustrated at 25 and 26 may optionally be sunk into the floor 19 of the water body and the elements 11 positioned over those pilings to further secure the reformation 10 in place. In this optional configuration, of course, sufficient apertures or openings are provided in the base 12 to accommodate the pilings 25 , 26 .
[0043] The beach entry reef formation 10 , as shown in FIG. 1 , is perhaps the most basic and common profile for island construction. This form emulates the gradual sloping entry from an island into an ocean or sea, lake or other water body, via a 15-30 degree sloping ramp. This reef formation is constructed with engineered concrete and steel reinforcement preferably. Glass fibers and chemical add mixtures to the cement may be added as required and as will be appreciated by those of skill in the art.
[0044] Moreover, a chemical resistant coating can be applied to the concrete structure where deemed desirable. The finish on the ramp or upper surface 16 may be simulated beach pebbles or cement mix with internal coloring, so as to proximate the color of the existing sand to be used. The front edge of the entry form, as noted above, may also display or emulate a simulated coral reef texture to achieve the highest degree of realism possible.
[0045] The beach entry form may be mechanically attached to the ocean floor 19 using piers, columns, pilings 25 , 26 , soil mails or composite adhesives. Nevertheless, the primary anchoring mechanism for the beach form comprises the weight of both the concrete form, which includes the base 12 , walls 13 , 14 , 15 and the ramp surface 16 , and any chamber with fill material, as illustrated at 27 .
[0046] It will be further appreciated that an entire island can be constructed using the elements described and shown in FIG. 1 . For example, a plurality of reef formation elements 11 to form a reef formation 10 can be pre-manufactured on a dry land site and conveyed by barge or other expedient to a site where an island is to be formed.
[0047] There, a plurality of the elements 11 can be sunk in a predetermined fashion and pattern in order to define an entire island, such as island 28 shown in FIG. 1 and in a water body where there was previously no island. Accordingly, the beach entry reformation 10 comprises a construction which extends both below and above the water line 11 in order to form both under water and above water base to define an island of any particular configuration or design where the island is primarily formed of the sand 22 . Alternately, elements 11 may be used to extend existing island or land mass features.
[0048] Turning now to FIG. 2 , there is shown therein a replaceable coral wave break formation 30 , including a replaceable element 31 and an underwater element 32 . Underwater element 32 is similar to the element 11 of FIG. 1 , in that it includes walls or beams 33 and 34 , defining chambers 35 , 36 . Elements 31 , 32 can be pre-constructed offsite and moved to an appropriate position in a water body, such as water body 37 , to provide a coral wave break formation 30 , as shown. The lower element or underwater element 32 , in addition, has a cementitious base 38 with an inwardly or land-extending projection 39 for covering by the sand 40 of the island for anchoring purposes. Similarly to the formation of FIG. 1 , pilings, piers, columns or other devices may be optionally used in order to hold the formation elements 32 , 31 in place. These are not shown for purposes of clarity. Chambers 35 , 36 may also be filled with a weighty ballast material, such as any cementitious material, rocks, pebbles or the like, for securing the element 32 in position on the floor 41 of the water body 37 .
[0049] The elements 31 and 32 are operationally interconnected by any suitable expedia, such as a rib 43 , while the element 31 can be removably interconnected with the element 32 , so that the element 31 can be replaced for maintenance or thematic change. Aesthetically, the respective shells 44 , 45 of elements 32 , 31 are configured and finished to take on the appearance of a reef or any other suitable rock-like appearance. Upon any undesirable damage of the element 31 due to the surface or at the water line of the water body 37 , the element 31 can be replaced. It will be appreciated that the shells 44 , 45 of the elements 32 , 31 are supported by any internal framework structures and may be supplied as an integral shell or may be supplied by pneumatically blowing cement material over a form or other mesh-like material or a rebar matrix in formed shapes as desired.
[0050] The replaceable coral wave break 30 provides a simple, realistic termination of an island 47 edge along a shoreline without offering a sand beach. Such a formation 30 emulates preferably a rugged coral coastline of an island by displaying a sculpted a coral rock finish at the water's edge and comprising the shell 45 of the element 31 . The formation 30 is constructed, preferably with engineered concrete and steel reinforcement framework (not shown). Glass fiber or chemical add mixtures to the cementitious material may be added as required for aesthetic effect or strength, chemical resistant coatings for saline resistance may be utilized and finishes on the subsurface element 32 , such as a shell 44 , may be provided as simulated coral rockwork or other aesthetic naturally appearing shapes. The formation 30 can be mechanically or chemically attached to the water body floor 41 , using piers, columns, pilings, soil nails or composite adhesives, but the primary anchoring mechanism will be the weight of the concrete form, including the base 38 , the walls 33 , 34 , the shells 44 , 45 and any ballast material in the chamber 35 , 36 .
[0051] Finally, and as noted, the section or element 31 exposed to the water line or breaking waves is replaceable, to allow for easy maintenance or repair. Again, it will be appreciated that a plurality of elements 31 , 32 in cooperation with each other can be operationally interconnected together to define an entire island 47 or only a portion or shoreline of an island, where none exited before, or as an extension of an existing island.
[0052] Turning now to FIG. 3 , it will be appreciated that the figure illustrates a cliff rock extending from a sea floor well above a water line WL to provide a dynamic, yet realistic transition from an island 50 to a water body 51 over the floor 52 . Accordingly, the cliff rock formation 53 will preferably emulate a rugged, vertical rock cliff typical of natural islands, such as those found in Greece, for example. The formation 53 is defined by an element 54 and an element 55 , each of which support a shell 56 , which is finished to emulate and present aesthetically a vertical rock cliff. Thus, a plurality of elements 54 , 55 are operably set, side by side, in connection with an integrated shell 56 to define a formation 53 . Element 54 comprises a base 57 with walls 58 , 59 defining a chamber 60 and with an upper surface 61 . The element 55 comprises a plurality of frame structural members 63 , 64 , 65 and vertical members 66 , 67 .
[0053] The areas defined by the walls 58 , 59 and surface 61 of element 54 and the various volumetric areas defined by the structural frame member 63 , 64 , 65 and the walls 66 , 67 may be filled with ballast in order to position an anchor to formation 53 . The elements 54 , 55 can be constructed offsite and moved by barge or other transport expedients to a site to form a rock wall extending from the water body floor 52 . In addition, elements 54 , 55 , together with the aesthetic shell or facade 56 can be used to define in whole or in part, an entire island 50 , or only a portion thereof, or an extension of an existing island. As in the other embodiments, the formation and its elements are constructed of engineered concrete and steel reinforcement, preferably, with glass fibers and chemical admixtures as desired or required, chemical resistant coatings for saline resistance and an aesthetic finish of simulated coral or other type of rockwork on the subsurface portion 69 of the shell 56 .
[0054] The formation 53 may be anchored by piers, columns or pilings chemically to the floor 52 or by any other expedient as mentioned with respect to the other embodiments, but the with the primary anchoring mechanism is the weight of the elements as described above and the weight of any ballast filling the various chambers and volumetric areas as illustrated in the figure.
[0055] Turning now to FIG. 4 , there is illustrated a cliff walk formation 70 comprising an above water facade or shell 71 and a shell 72 extending from above the water line WL of a water body 73 to below that water line toward the water body floor 74 . Essentially, what is shown in FIG. 4 is somewhat a combination of the structures described above in FIGS. 1 and 3 . Accordingly, an element comprising the shell 72 includes walls 75 and 76 disposed on a base 77 with a rearward projection 78 thereon and defining chambers which can be filled with ballast as shown.
[0056] A second element 80 comprises a plurality of frame members 81 , 82 and 83 , together with walls 84 and 85 . The shell 71 may be like that shell 56 described above with respect to FIG. 3 , while the shell 72 may be like that shell member 16 as described with respect to FIG. 1 and it will be appreciated that the shell 71 is preferably comprised of a rocklike configuration or emulation and that the intersection at 86 of the shell 71 , 72 are defined with respect to the shells, so that a person can walk above the shell or on the shell 72 and under the shell 71 as illustrated in FIG. 4 . Shell 71 , of course, could be covered with a layer of sand (not shown). The formation 70 provides a dynamic, yet realistic transition from an island to the water body 73 and emulates a rugged vertical rock cliff typical of natural islands. This cliff rock formation 70 is constructed as noted with respect to the elements of the formations described in the prior figures, finished in a similar way but as desired with respect to the aesthetic view of the finish or facade and mounted on the floor 74 in a similar way, with the volumetric areas between the frame members and the wall structures being filled as desired with ballast so as to anchor the formation 70 .
[0057] It will be appreciated that the shell 72 can be replaced if decayed as a result of the breaking wave action and the gently sloping beach entry provided by the shell 72 can be finished with an exposed beach pebble texture or the like. Moreover, it will be appreciated that walls or members 81 - 85 may define inhabitable spaces for residential, commercial, resort or hotel facilities or the like.
[0058] FIG. 5 illustrates a spire island formation 90 extending upwardly from a water body floor 91 above the water line WL as shown in the figure. The spire island formation 90 includes a plurality of frame members 92 - 94 and cross-structural members 95 - 97 disposed all on a base 98 , configured to be placed within the floor 91 of the water body 99 . A shell 100 is mounted on the framework 92 - 97 similarly to the shells as described above and the facade provided by the shell 100 is designed aesthetically to provide a realistic transition from below the water line to above the water line in an island or spire island format. Such a formation presents a dynamic and visually exciting formation from the floor 91 to well above the water line WL. It provides a majestic, yet realistic transition from the water line to an exclusive island formed by the shell 100 above the water line WL and emulates a rugged, vertical rock formation typical of Southeast Asia and more specifically Thailand. The exposed shell above the water line WL is constructed to achieve the highest degree of aesthetic realism possible, while other components of the spire island formation 90 are similar to those described above.
[0059] The framework as disclosed in FIG. 5 , together with the shell, can be manufactured offsite and transported by barge or other facility to a site where it is desired to erect a single or multiple spire islands. The formations 90 are attached to water body floor 91 in any suitable manner as described above and sections of the shell proximate the water line WL may be easily changed out or repaired due to any decay by water wave action. Elevated or sloping beach areas could be added to this formation in a manner as will be appreciated by extending the internal framework in the shell accordingly, such as suggested, for example, in FIG. 1 .
[0060] Such a spire island formation may also be used as an architectural or structural base for a number of facilities, such as commercial facilities or residential facilities, or resort facilities, such as hotels and the like, all located within appropriate framework as illustrated by the members 92 - 98 of FIG. 5 . The formation 90 could also serve as a primary design for communication stations, early warning markers or relays, military applications, animal containment structures, sea life parks, sail in amphitheaters and other architectural and thematic projects.
[0061] Accordingly, it will be appreciated that the features as shown in FIG. 5 can be modified aesthetically and with respect to space and extension in order to provide the architectural base or foundation for a number of buildings and facilities in a place where there was nothing but water before and limited only by the imagination of the designer.
[0062] With further reference to FIG. 5 , it will be appreciated that the formation 90 can be adapted for use, not only rising from the floor of a water body, but also used upon existing island or land structures to define a natural rock or coral terrain housing a wide variety of residence, commercial, hotel, resort or protected marina facilities within the spaces, and optionally extending outwardly thereof, defined by walls and members 92 - 98 and by shell or shells 100 , or thereunder.
[0063] Moreover, it will be appreciated that the scope of size of the formation may be hundreds of feet in height and in breadth in order to accommodate the noted facilities and that the outside appearance is limited only by the imagination of the shell designer and the interior architect.
[0064] FIGS. 6-9 illustrate further modifications of the invention as will be appreciated, including adaptations of the structures, formations and constructions as described above, to serve different purposes. As an example, in FIG. 6 , a coastline undercut formation 110 is described, where walls 111 and 112 are provided on a base 113 , having a rearward projection 114 . The shell 115 , such as those described above and providing a coral-like appearance, is provided in chambers defined by the shell 115 , the walls 111 , 112 and the base 113 can be filled with a ballast for mounting on a floor 116 of a water body 117 below the water line WL. A shell formation 118 is provided extending above the wall 112 and above the shell 115 to provide an undercut emulating the undercut rock profiles typical of saltwater volcanic islands in the Pacific.
[0065] The finish on the subsurface rock shell 115 may be simulated coral or rockwork. The finish on the exposed shell above the water line WL is constructed to emulate the highest degree of rock realism possible. Sand 119 fills in behind the shells 118 and the below water line structure to provide ballasts to anchor the formation 110 while the above water line shell 115 is finished with an exposed beach pebble texture or similar texture with natural sand optional thereon. The overhead feature of the coastline undercut formation 110 offers protection from the elements and provides a protected walkway above the water line WL.
[0066] FIG. 7 illustrates a protected beach walk formation 124 , providing an elevated, protected beach area 125 for walking or the like. The formation 124 includes an element 126 formed of walls 127 , 128 and base 129 , with a rearwardly projecting element 130 . A shell 131 emulates a coral or rock facade and can be replaceable if decayed by the wave action at the water line WL of water body 132 above water body floor 133 .
[0067] Turning to FIG. 8 , there is shown an elevated sunbathing platform which constitutes adaptation of the coral wave break formation of FIG. 2 and the coastline undercut formation of FIG. 6 , for example. Accordingly, in FIG. 8 , there is an element 31 replaceably disposed on an element 32 which resides in the water body 136 . A structural formation or element 138 including at least walls 139 and 140 support a shell 141 which rises behind and over the element 31 and supports a sunbathing platform 144 , as illustrated in the figure.
[0068] Elements 31 and 32 are constructed like those described in FIG. 2 upon a base 145 , similar to that base 38 of FIG. 2 mounted on or just within the floor 146 of the water body 136 . Accordingly, the construction shown in FIG. 8 provides an elevated, protected platform for sunbathing, for example. This formation 148 provides an elevated platform for sunbathing as a simulated, cantilevered concrete and sand platform, along with a replaceable coral rock wave break to protect beach sand from erosion.
[0069] Such a formation 148 is particularly useful for installation in areas where undercurrents and tide changes create significant erosion problems. The features as disclosed in FIG. 8 are similar to those as disclosed with respect to the other embodiments of the invention described above with respect to the interior frame work, mounting and ballast systems.
[0070] As well, it will be appreciated that the cantilevered area of the shell 118 as shown in FIG. 6 may also be supported by additional framework and internal support as illustrated diagrammatically only in FIG. 8 .
[0071] In FIG. 9 , there is illustrated a erosion protection formation 150 . Formation 150 includes a base element 151 mounted on or within a floor 152 of a water body 153 beneath a water line WL. Such an erosion preventing formation may be inserted in an existing island or in an island constructed by the methods described herein, where the natural line of the sand, for example, sloping to the water line and below, is shown in the dotted line at 154 .
[0072] Formation 150 further includes a shell 155 made of suitable cementitious or synthetic material and simulating coral or rock formations. The shell 155 is supported by any suitable internal structures, including framework such as at wall 156 and any other framework not shown. Wall 156 , together with the base 151 and the shell 155 define a chamber into which can be placed a variety of ballast material to maintain the formation 150 in place. It will also be appreciated that formation 150 can be used as an independent element or as a series or independent elements interconnected or spaced apart along a shoreline for the prevention of erosion and that the finish of the shell 155 is treated to emulate rock or coral materials in a natural manner as will be appreciated.
[0073] It will also be appreciated that additional wall structures such as at 157 and covering shells or coatings 158 can be provided on the base 151 where rear portions of the formation 150 are open for receiving ballast. Such formations can be used in areas where undercurrents and tide changes create significant erosion problems.
[0074] Turning now briefly to FIG. 10 , it will be appreciated that the figure illustrates an overhead or plan view of an animal containment system 170 , wherein the entire structure is built up from the bed or floor of a water body and is designed such as shown in FIG. 10 to define an animal containment area 171 . In this regard, it will be appreciated that the structures, such as at 172 , 173 , 174 , 175 and 176 can all be manufactured of cementitious or synthetic materials such as those described above and include essentially an internal framework or support of steel or concrete structure and an outer shell of cementitious or synthetic material which is designed and treated to present the aesthetic appearance of a rock or coral facade rising above a water level in order to define the island-like structures 172 - 176 . When these are formed from the sea floor, as shown, it will be appreciated that the areas 171 , 171 A can be defined as animal, fish or aquatic life containment areas. This is provided by the fact that the island elements 172 - 176 extend from the floor of the water body above that floor and outwardly and upwardly into the atmosphere. Appropriate gates (not shown) are disposed at areas 178 , 179 , 180 and 182 to prevent the ingress or egress of animals, fish or other aquatic life. Such gates can be manufactured of any suitable structures and can be raised or lowered where desired, to permit ingress or egress.
[0075] Accordingly, the island structures 172 - 176 can be formed, such as by the elements or features of the preceding FIGS. 1-9 , to define an island complex which itself defines animal containment areas 171 , 171 A. Means for accessing the areas by various boats can be provided for viewing. Also, beach structures and/or inhabitable structures can be defined within the island structures 172 - 176 as defined by the utilization of the architectural structures and components previously described.
[0076] Turning now to FIGS. 11-15 , other applications and modifications and embodiments of the invention herein will be described. As an example, in FIG. 11 , there is shown a beach stabilization formation 190 , particularly useful for installation in areas of either newly-constructed or existing island where undercurrent or tide changes create erosion problems. The beach stabilization formation 190 , as shown in FIG. 11 , includes an anchor element 191 , a forward element 192 and a tie element 193 . A water body 194 is defined in part by a floor 195 and a water level WL.
[0077] A beach is defined at 196 comprising an area of sloping sand, running and transitioning from positions above the water line WL to positions below the water line as illustrated. The elements 191 , 192 may comprise cementitious forms constructed offsite and moved to the positions as shown via barges or other transport facilities. When in place, the area above the ties 193 are filled with sand and the element 192 is provided with a rock or coral simulating surface 197 as shown in solid line, or 198 as shown in phantom line, exposed to the water of the water body 194 .
[0078] A plurality of elements making up a single formation 190 or a single element making up a formation 190 can be used in such areas to prevent and minimize erosion and undercurrent degradation of the sloping sand or beach area 196 .
[0079] Turning now to FIGS. 12A and 12B , there are various formats shown for defining a perimeter outline of an island made according to the above-described architectural formations noted in the previous figures. Accordingly, in FIG. 12A , a bookend formation 200 is described having bookend elements 201 and 202 comprised of cementitious or other materials in the formats shown and emulating on their outer surfaces, preferably coral or coral rock faces. These elements 201 , 202 are secured to the floor 203 of a water body 204 , a ballast or fill material such as rock or pebbles or other cementitious material 205 is disposed between the elements 201 , 202 and the area above the fill 205 is provided with sand as at 206 , a portion of which extends above the water line WL.
[0080] Elements 201 , 202 are held in place, preferably by columns, pilings or piers 207 , 208 as desired. Such architectural formation as described in FIG. 12A can thus form a sandbar, for example, just at or slightly off the shorelines defined by the manmade islands of the preceding figures. Pilings (not shown) may extend inside the bookend elements 201 , 202 for achieving maximum structural integrity. It will be appreciated that FIG. 12 shows a cross-section of an island, and that a plurality of elements 201 , 202 may be used to define a perimeter of an island, peninsula or the like.
[0081] FIG. 12B illustrates a bookend reformation 210 comprised by bookend elements 211 , 212 , each secured by a piling 213 , 214 . These differ slightly from the bookend elements 201 , 202 in that bookend elements 201 , 202 of FIG. 12A are provided with extensions 209 which lie under the fill 217 and/or the sand 218 . In FIG. 12B , pilings 213 , 214 are simply extended upwardly into the elements 211 , 212 and downwardly into the floor 215 of a water body 216 to provide support for the elements 211 and 212 on the floor and to help define an island or a sandbar or perimeter for an existing or a manmade island.
[0082] FIG. 13 illustrates a modification of the invention wherein a center support column is utilized to mount the formation structures as described above and is particularly useful where further support is needed for those structures. Accordingly, FIG. 13 illustrates a center support column formation 220 , including a center support column 221 , a tie rod 222 , a base 223 and a formation structure 224 , similar to those described above.
[0083] A manmade or natural island 225 has, for example, a sloping shoreline 226 extending from above to below the water line WL of a body of water 227 defined above a floor 228 . The formation 224 may be like those formations described above and by way of example only, without limitation, in FIGS. 1-4 and 6 - 9 , for example. It will be appreciated that this support column formation is particularly useful for attaching the forms 224 at the perimeter of the island to more centrally located columns 221 installed more toward the center of the island and providing by means of the base 223 and the tie 222 substantial support for counterbalancing and holding the formations 224 . Formations 224 , of course, and as noted, may comprise elements made from a series of internal framework, steel or concrete, covered by shell material as has been described above.
[0084] Turning now to FIG. 14 , there is described a slabbed coral formation 240 , particularly useful where a sand seabed, lakebed or water body bed does not constitute a suitable substrate for construction purposes. Coral slab formation 240 permits the production of thickened slabs of reinforced concrete to substitute for natural coral rock on which various architectural features as described above may be mounted more securely. However, where the bed of the water body 241 , rising above floor 242 is less substantial, the construction of FIG. 14 can be utilized. In this configuration, a base 244 of cementitious material is formed offsite and may be transported to the position desired in the water body 241 . These are lowered to the site and these concrete slabs 244 then provide a structural foundation for the subsequent installation of formations on top of the slabs. Accordingly, a formation such as at 246 is also formed on site. Formation 246 may include an element which includes at least a frame member 247 supporting a shell 248 which is formed as noted above, to emulate a coral rock or rock surface or facade. The area of voids between the structural frame member, such as at 247 and the shell 248 are filled, preferably with a cementitious material 249 to provide weight for the element 246 .
[0085] During the construction of the slab 244 , upstanding rods or anchors 250 are provided in the slab and extend upwardly. Once the shell and internal structured element is manufactured and transported to the site, it is lowered over the slab 244 and the cement 249 is filled, in order to hold down the element including the shell 248 and is solidly connected to the slab 244 through the anchor rods 250 . Thereafter, sand, such as at 252 , is poured over the base 244 and over the shell 248 to provide a natural above and below water appearance.
[0086] Turning to FIG. 15 , there is illustrated therein various adaptations of the formations and construction features noted above. For example, FIG. 15 illustrates a combination of the coral wave break reef formation of FIG. 2 , together with primarily underwater formation, which emulates a number of variable architectural and aesthetic structures. Accordingly, the formation 260 in FIG. 15 is a combination of a coral wave break element 261 such as shown and described in FIG. 2 , but together with an underwater facade at 262 within the water body 263 and above floor 264 .
[0087] Formation 262 as illustrated in FIG. 15 comprises, for example only, a themed finish, such as old columns or ruins illustrated or emulated as a shell 265 as part of an element 266 . Element 266 comprises walls 267 and upper surface 268 and a base 269 , similar to those described above and supporting the shell 265 . It will be appreciated that the shell 265 may be supported by any suitable means, such as those described above, and including concrete or steel forms and may be formed in any of a plurality of themed finishes, such as ruins or any other types of effects extending both above and below the water line WL.
[0088] In this connection, and with reference to the various formations as described in this application, various aesthetic and architectural features should be appreciated. For example, rock or rock simulation as an architectural finish can be utilized in connection with these structural features. It will also be appreciated that residential units, commercial facilities, resort condos, hotel suites or timeshare properties can be formed and reside within various portions of the formations ad described herein, both above and below water, while the application of manmade rockwork as the primary and secondary structural and architectural finish material for residential applications can substantially enhance those facilities.
[0089] Moreover, it will be appreciated that a variety of mechanical features can be utilized to provide other aesthetics to the manmade islands and formations described herein. For example, many of the formations as described may also provide options for installation of grading, plumbing and mechanical equipment to create artificial tides, waves and compactions of the sand to hold specific elements in places designed. For example, by creating a continuous artificial current of water above a sand surface, and a continuous suction below the sand bed, the sand can be held in place against the force of this natural current or natural waves. This may eliminate the need for beach dressing and manicuring. A further mechanical feature of the invention, while not shown, could comprise a wave generation machine within a harbor or atoll area of an artificial island made by these techniques as described herein. The wave machine could be used to generate artificial waves directed toward swimming guests or guest areas or in the marine or fish containment area as described above. Air bubblers could be used in the same way.
[0090] Moreover, since the formations described herein are manmade, lighting can be installed, both above and below the water lines and around the perimeters of the manmade island from underwater light fixtures as may be desired.
[0091] Moreover, underwater viewing windows can be installed at the perimeter of the island or in the animal and fish containment areas to allow for viewing from within inside one of the formations as described herein.
[0092] It should be also appreciated that the structures and concepts described herein can be applied or combined with existing artificial or natural island or land structures. The formations described will function to improve, enhance, strengthen, reduce erosion and provide aesthetic structures for human enjoyment. Thus the structures and features described herein can be retrofitted or adapted to existing island or land structures without the artificial bases illustrated, or can be used to provide wholly artificial islands and structures for human habitation and enjoyment.
[0093] Finally and turning to FIG. 16 , there is shown an overhead view of an entire island 270 which can be made entirely by man and arising from a floor of a water body and above that water body to provide, for example, harbor and fish or animal containment area 271 , internal coves, lakes and streams 272 and a variety of topography such as otherwise illustrated by the various shading, to provide an entire manmade residential, commercial or resort area. For example, sandy or beach areas 273 can be provided while taller structures such as 274 and 275 can be provided for overlooks, residences, hotels or the like. It will be appreciated that in the various areas, the architectural features and formations as described in the preceding figures can be used to define the beach or island perimeter areas, as well as rising above the beach or water line areas and in which hotels, condos, residences, timeshare units and commercial facilities, as well as harbors, marinas, golf courses, and other resort activity areas can be built.
[0094] Accordingly, the invention offers and provides a capacity, both structurally and as a process for providing artificial island and land structures for human commerce, vacation, residence, and resort areas where nothing but water existed before.
[0095] With reference to FIGS. 10 and 16 , such a manmade island could be built from the sea or water area floor where nothing existed above water level previously. Such an artificial island according to the invention could provide residential, vacation, postal and park areas, hotels, lighthouse, scuba diving, marine, marinas, aquatic and wetland preservation and viewing facilities among other facilities and structures, with the only limit being the imagination of the designer. The structures illustrated and the figures provide the structural base for below and above water line structures for natural aesthetic, buildings, marinas, viewing amphitheaters, natural concert venues and the like.
[0096] It will also be appreciated that where plural formations or elements are used to define an island perimeter, they may be operationally joined or connected in a way to prohibit or reduce water flow or leakage between them. In this regard, the shell surfaces could be adhered together or gaps between them bridged with materials also emulating rock, coral or the like.
[0097] Finally, it will be clearly appreciated that an entire manmade island can be erected with these formations, architectural structures, aesthetic treatments and these methods where nothing existed before but water. Various formations or formation elements can be operably combined to provide an island of varying terrain, including sloping and protected beaches, coral and rock, sea to island transitions, rising terrain, hills, cliffs and mountains and underwater and above water facilities for human use and appreciation. One form of element or formation can be used to transition into another for terrain variations or effect, or to define desirable features such as beach, cliffs, lake, undercuts, erosion protection, harbors marine life, amphitheaters hotel condominiums, resorts, residences, retail space, marinas and the like. Perimeter formations are placed, then the interior is built up, all from the floor of the water body site.
[0098] These variations and modifications will be readily appreciated by those of ordinary skill in the art to which this invention pertains and applicant intends to be bound only by the claims appended hereto. | A method of making an island including the steps of: manufacturing a plurality of formations; transporting the formation to a site in a water body; assembling said formations proximate one another; said formations defining an artificial island structure with both below and above water line components. Methods are described, as well as methods and components for both island and existing island and land enhancements. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of U.S. patent application Ser. No. 10/434,749 filed May 9, 2003, now U.S. Pat. No. 6,768,797, which is a continuation of U.S. patent Ser. No. 10/081,750, filed Feb. 21, 2002, now abandoned, which is a continuation of application Ser. No. 09/369,382, filed Aug. 5, 1999, now U.S. Pat. No. 6,385,316, issued May 7, 2002, which is a continuation of application Ser. No. 08/815,347, filed Mar. 11, 1997, now U.S. Pat. No. 6,075,859, issued Jun. 13, 2000, all assigned to the assignee hereof and hereby expressly incorporated herein.
BACKGROUND OF THE INVENTION
I. Field of the Invention
The present invention relates to communications systems. More particularly, the present invention relates to a novel and improved method for encrypting data for security in wireless communication systems.
II. Description of the Related Art
In a wireless communication system, it is desirable for the service provider to be able to verify that a request for service from a remote station is from a valid user. In some current cellular telephone systems, such as those deploying the AMPS analog technology, no provision is made to deter unauthorized access to the system. Consequently, fraud is rampant in these systems. One fraudulent means for obtaining service is known as cloning, in which an unauthorized user intercepts the information necessary to initiate a call. Subsequently, the unauthorized user can program a mobile telephone using the intercepted information and use that telephone to fraudulently receive telephone service.
To overcome these and other difficulties, many cellular telephone systems have implemented authentication schemes such as that standardized by the Telecommunications Industry Association (TIA) in EIA/TIA/IS-54-B. One facet of this authentication scheme is encryption of information, transmitted over the air, that is required to receive service. This information is encrypted using the Cellular Message Encryption Algorithm (CMEA). The CMEA algorithm is disclosed in U.S. Pat. No. 5,159,634, entitled “CRYPTOSYSTEM FOR CELLULAR TELEPHONY”, incorporated by reference herein.
Several major weaknesses have been discovered in CMEA which allow encrypted information to be deciphered using current standard computational equipment in a relatively short period of time. These weaknesses will be thoroughly outlined hereinafter followed by a description of the present invention which overcomes these weaknesses. CMEA has been published on the Internet, hence these weaknesses are open for discovery by anyone with an interest in doing so. Thus, a new algorithm for encryption is desirable to replace CMEA to avoid the interception and fraudulent use of authentication information necessary to initiate cellular service.
SUMMARY OF THE INVENTION
The present invention is a novel and improved method for data encryption. The present invention is referred to herein as Block Encryption Variable Length (BEVL) encoding, which overcomes the identified weaknesses of the CMEA algorithm. The preferred embodiment of the present invention has the following properties:
Encrypts variable length blocks, preferably at least two bytes in length; Self-inverting; Uses very little dynamic memory, and only 512 bytes of static tables; Efficient to evaluate on 8-bit microprocessors; and Uses a 64 bit key, which can be simply modified to use a longer or shorter key.
The first weakness identified in CMEA is that the CAVE (Cellular Authentication Voice Privacy and Encryption) table used for table lookups is incomplete. It yields only 164 distinct values instead of 256. The existence of a large number of impossible values makes it possible to guess return values of tbox( ) or key bytes, and verify the guesses. This first weakness is mitigated in the present invention by replacing the CAVE table with two different tables chosen to eliminate the exploitable statistical characteristics of the CAVE table. These tables, called t 1 box and t 2 box, are strict permutations of the 256 8-bit integers, where no entry appears at its own index position. In addition, t 1 box[i] does not equal t 2 box[i], for all values of i. These two tables were randomly generated with candidates being discarded which did not meet the above criteria.
The second weakness of CMEA is the repeated use of the value of a function called tbox( ), evaluated at zero. The value tbox( 0 ) is used twice in the encryption of the first byte. This makes it possible to guess tbox( 0 ) and use the guess in determining other information about the ciphering process, notably the result of the first step of CMEA for the last byte, and the arguments of the two values of tbox( ) used in encrypting the second byte. It also makes it possible, through a chosen-plaintext attack, to determine tbox( ) by trying various plaintext values until a recognized pattern appears in the ciphertext. This second weakness is mitigated by changing the self-inverting procedures used in CMEA to a preferred set of procedures providing better mixing. This is done by introducing a second pass using a different table (t 2 box). In this situation there are two values of tbox( ) derived from different tables with equal significance which serve to mask each other.
A related weakness in CMEA is that information gathered from analyzing texts of different lengths can generally be combined. The use of the second critical tbox( ) entry in BEVL depends on the length of the message and makes combining the analysis of different length texts less feasible.
A third weakness discovered in CMEA is incomplete mixing of upper buffer entries. The last n/2 bytes of the plaintext are encrypted by simply adding one tbox( ) value and then subtracting another value, the intermediate step affecting only the first half of the bytes. The difference between ciphertext and plaintext is the difference between the two values of tbox( ). BEVL addresses this third weakness by performing five passes over the data instead of three. The mixing, performed by CMEA only in the middle pass, is done in the second and fourth passes which mix data from the end of the buffer back toward the front. The middle pass of CMEA also guarantees alteration of at least some of the bytes to ensure that the third pass does not decrypt. In an improved manner, BEVL achieves this goal in the middle pass by making a key dependent transformation of the buffer in such a way that at most a single byte remains unchanged.
CMEA's fourth weakness is a lack of encryption of the least significant bit (LSB) of the first byte. The repeated use of tbox( 0 ) and the fixed inversion of the LSB in the second step of CMEA results in the LSB of the first byte of ciphertext being simply the inverse of the LSB of the first byte of plaintext. BEVL avoids this fourth weakness through a key dependent alteration of the buffer during the middle pass which makes the LSB of the first byte unpredictable on buffers of two bytes or more in length.
A fifth weakness of CMEA is that the effective key size is 60 rather than 64 bits. As such, each key is equivalent to 15 others. BEVL increases the number of table lookups while decreasing the number of arithmetic operations, ensuring that all 64 bits of the key are significant.
Finally, CMEA's tbox( ) function can be efficiently compromised by a meet-in-the-middle attack. Once four tbox( ) values are derived, the meet-in-the-middle attack can be accomplished with space and time requirements on the order of 2^30, independent of the composition of the CAVE table. BEVL addresses this in a number of ways. The construction of the tbox( ) function recovers two unused bits of the key. The repetition of the combination with the least 8 bits of the encryption key at both the beginning and end of tbox( ) means that the minimum computation and space should be increased by eight bits. Since there are two sides of each table, and two different tables, the minimum complexity should be increased by another two bits, leading to a minimum space and time requirement on the order of 2^42. Further, the meet-in-the-middle attack on CMEA requires the recovery of at least some of the tbox( ) entries. This is made more difficult using BEVL, which requires simultaneous attacks on two separate sets of tbox( ) values, which tend to disguise each other.
BRIEF DESCRIPTION OF THE DRAWINGS
The features, objects, and advantages of the present invention will become more apparent from the detailed description set forth below when taken in conjunction with the drawings in which like reference characters identify correspondingly throughout and wherein:
FIG. 1 is a block diagram illustrating the encryption system of the present invention;
FIG. 2 is a flow diagram of an exemplary embodiment of the method of encrypting a block of characters in the present invention;
FIG. 3 is a “C” program implementing the exemplary embodiment of the method of encrypting a block of characters in the present invention;
FIG. 4 is an exemplary embodiment of t 1 box; and
FIG. 5 is an exemplary embodiment of t 2 box.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The exemplary embodiment of the present invention consists of a first station 1000 encrypting data for wireless transmission to a second receiving station 2000 , as depicted in FIG. 1 . First station 1000 can be a remote station transmitting to a second station 2000 , which could be a base station. Alternatively, first station 1000 could be a base station transmitting to a second station 2000 , which could be a remote station. In all likelihood, both remote and base stations will have encryption and decryption means, as well as transmission and reception means, but the simplified system shown in FIG. 1 shows clearly the elements required to enable the present invention. Further, the benefits of this invention are not limited to wireless communications but can be readily applied in any situation where secure data must be transmitted over a medium which is susceptible to interception, as will be well understood by those skilled in the relevant art.
In FIG. 1 , memory 10 containing the necessary data for encryption according to the BEVL algorithm of the present invention is connected with processor 20 . In the exemplary embodiment, processor 20 is a relatively simple 8-bit microprocessor, capable of executing instructions stored in BEVL code 19 . Processor 20 contains an arithmetic logic unit (ALU, not shown) capable of performing simple 8-bit instructions such as bitwise exclusive OR (referred to simply as XOR or denoted≈ hereinafter), integer addition and subtraction, and the like. Processor 20 is also capable of general program flow instructions and the ability to load and store values from a memory, such as memory 10 . Those skilled in the art will recognize that these requirements are quite minimal, making the present invention quite suitable to applications where size and/or cost requirements make simple microprocessors desirable, such as in portable devices. Clearly the present invention can easily be implemented using more powerful microprocessors as well.
Memory 10 contains tables t 1 box 12 and t 2 box 14 , an encryption key 16 , and the code to be executed (BEVL code) 19 . Data to be encrypted is input to processor 20 , which stores that data in memory 10 in a location referred to as data 18 . Although FIG. 1 depicts all these elements in a single memory, it is understood that a plurality of memory devices could be used. In the preferred embodiment, the tables 12 and 14 as well as BEVL code 19 are stored in non-volatile memory such as EEPROM or FLASH memory. These portions of the memory need not be writeable.
Encryption key 16 can be generated by a number of means that are well known in the art. A simple embodiment may have key 16 in non-volatile memory that is programmed once at the time the station is activated for service. In the exemplary embodiment, key 16 is generated and changed according to the protocol as set forth in the aforementioned EIA/TIA/IS-54-B.
The data to be encrypted, data 18 , is stored in random access memory (RAM). The encryption will be performed “in place”, which means the memory locations holding the unencrypted data at the beginning of procedure will also hold the intermediate values as well as the final encrypted data.
Data 18 is encrypted in processor 20 according to BEVL code 19 , utilizing t 1 box 12 , t 2 box 14 , and encryption key 16 . A description of the encryption process is detailed hereinafter.
Encrypted data 18 is delivered by processor 20 to transmitter 30 where it is modulated, amplified and upconverted for transmission on antenna 40 .
Antenna 50 receives the data and passes it to receiver 60 where the data is downconverted, amplified, demodulated, and delivered to processor 70 . In the exemplary embodiment, the format for the wireless communication between the two stations depicted in FIG. 1 is described in “Mobile Station-Base Station Compatibility Standard for Dual-Mode Wide Band Spread Spectrum Cellular System”, TIA/EIA/IS-95-A. The use of CDMA techniques in a multiple access communication system such as a wireless telephone system is disclosed in U.S. Pat. No. 4,901,307, entitled “SPREAD SPECTRUM MULTIPLE ACCESS COMMUNICATION SYSTEM USING SATELLITE OR TERRESTRIAL REPEATERS,” assigned to the assignee of the present invention, and incorporated by reference herein. The use of CDMA techniques in a multiple access communication system is further disclosed in U.S. Pat. No. 5,103,459, entitled “SYSTEM AND METHOD FOR GENERATING SIGNAL WAVEFORMS IN A CDMA CELLULAR TELEPHONE SYSTEM,” also assigned to the assignee of the present invention, and incorporated by reference herein.
Processor 70 , which has the same requirements as processor 20 , is coupled to memory 80 . Memory 80 is comprised of memories 82 , 84 , 86 , 88 , and 89 which are analogous to memories 12 , 14 , 16 , 18 , and 19 , respectively. Processor 70 stores the encrypted data in data memory 88 . Key 86 is determined in like fashion to key 16 , described previously. Tables 82 and 84 are identical to tables 12 and 14 . Since the data processing in this invention is self-inverting, BEVL code 89 , identical to BEVL code 19 , is executed in processor 70 in conjunction with t 1 box 82 , t 2 box 84 , and key 86 on encrypted data 88 , just as was done in the encryption process of data 18 . As before, the data processing is performed “in place”, and the result in data 88 will be the decrypted data. Processor 70 retrieves the decrypted data from memory 80 and delivers it for subsequent use through the data output. In the exemplary embodiment, the resultant data will be used in authentication procedures as disclosed in EIA/TIA/IS-54-B.
FIG. 2 illustrates a flow chart of the method used by processors 20 and 70 in conjunction with previously described memory elements 10 and 80 , respectively. As mentioned previously, the encryption process is self-inverting, meaning the decryption process is the same as the encryption process. Hence, only the encryption process will be described in detail. The decryption process will be obvious by substituting the encrypting blocks of FIG. 1 with the analogous decrypting blocks of FIG. 1 as set forth previously.
Block 99 marks the beginning of the encryption process. An array of characters named buf[ ] is used to describe the characters to be encrypted as stored in data memory 18 . The variable n denotes the length of the message to be encrypted in terms of number of characters. As stated previously, one of the improvements present in the BEVL process is the five pass encryption that takes place. Each of the five passes has been blocked out in dashed lines and labeled 1 - 5 to make them easy to distinguish. Each pass has notable similarities and differences. Passes 1 , 3 , and 5 use the table t 1 box 12 and work from the beginning of the buffer towards the end. Passes 2 and 4 use the table t 2 box 14 and work from the end of the buffer until the beginning is reached. BEVL's self-inverting property comes from the fact that pass 3 is self-inverting, while pass 1 is the inverse of pass 5 and pass 2 is the inverse of pass 4 .
In the preferred embodiment of the present invention, the passes are made in opposite directions. In alternative embodiments, passes could progress in the same direction, with alternating passes using the same or different tables (re-using the same table in multiple passes does make the encryption more robust, but not as robust as when different tables are used). Inserting additional passes is another alternative which can be used in combination with either approach. In the situation where passes are made in the same direction, modifications to the first buffer entry are more predictable, with predictability decreasing in modifications further down the buffer. When alternating opposite pass directions are used, the modification to the first byte in the buffer is fairly predictable. However, the modification to that byte in the second pass depends on all the bytes in the buffer, making it much less predictable. In similar fashion, the modification to the last byte in the buffer depends on all the bytes in the buffer during the first pass, while a more predictable change is made in the second. Since the predictability of change is distributed more evenly using passes in opposite directions, doing so is much preferable to using multiple passes in the same direction. Note that pass 3 doesn't really have a direction, since the change made would be identical either way.
In each pass, a function tbox( ) is used. It is in this function that key 16 is incorporated. The parameters passed to function tbox( ) consist of a 256 byte table which will either be passed t 1 box 12 or t 2 box 14 , and an index labeled tv. In the exemplary embodiment, tbox( ) is defined as:
t box( B,tv )= B[B[B[B[B[B[B[B[B[tv≈k 0]+ k 1]≈ k 2]+ k 3]≈ k 4]+ k 5]≈ k 6]+ k 7]≈ k 0], (1)
where
k 0 through k 7 denote eight 8-bit segments which when concatenated form the 64-bit key 16 ; B[x] is the xth 8-bit element of an array B; ≈ denotes the bit-wise exclusive OR operation; and + represents modulo 256 addition.
In an alternative embodiment, where a key of a certain length provides encryption that is considered too strong, the key strength can be artificially limited without changing the length of the key by altering the tbox( ) function. For example, a 64 bit key can be artificially limited to 40 bits by using the 64 bit key in such a manner that it is in an equivalence class of 2^24 others while still ensuring that any single bit change to the key will produce a different result. The following definition of tbox( ) exhibits the recommended variation to render a 64 bit key effectively a 40 bit key:
tbox ( B , tv ) = B [ B [ B [ B [ B [ B [ B [ B [ B [ tv ≈ k0 ] + k1 ] ≈ ( k2 ≈ k3 ) ] + ( k2 ≈ k3 ) ] ≈ ( k4 ≈ k5 ) ] + ( k4 ≈ k5 ) ] ≈ ( k6 ≈ k7 ) ] + ( k6 ≈ k7 ) ] ≈ k0 ] , ( 2 )
where
k 0 through k 7 denote eight 8-bit segments which when concatenated form the 64-bit key 16 ; B[x] is the xth 8-bit element of an array B; ≈ denotes the bit-wise exclusive OR operation; and + represents modulo 256 addition.
The tbox( ) function is designed such that each of the intermediate operations are permutations, meaning each input has a one-to-one mapping to an output. In the exemplary embodiment, the operations used are modulo 256 addition and logical exclusive OR. If the input value passed to tbox( ) is a permutation, and the table lookup is as well, the use of these functions guarantees that the output of tbox( ) will also be a one-to-one function. In other words, the tbox( ) function as a whole is guaranteed to be a permutation if the table passed to it also is. This is not the case for CMEA, where the steps in the tbox( ) function are not one-to-one. Therefore, in CMEA, even if the CAVE table, which is not a permutation, were to be replaced with a table which is a permutation, the output of tbox( ) still would not be a permutation. Conversely for BEVL, any choice of one-to-one functions for combining key material to generate the final permutation would be acceptable. The exemplary embodiment is one such method. Alternative methods can easily be substituted by those skilled in the art which still conform to this permutation principle of the present invention. Intermediate functions which do not preserve the one-to-one nature of the output can alternatively be employed in the BEVL tbox( ) function, but the results would be sub-optimal.
A further improvement included in the definition of tbox( ) is that some of the key bits are used both at the beginning and at the end. In the exemplary embodiment key byte k 0 is used, but alternative embodiments can employ any of the key bits and accomplish the same improvement. The use of the same value defeats the meet-in-the-middle attack. Failing to reuse at least some of the key information at both the beginning and end allows a straightforward, albeit computationally complex, derivation of the key from a small number of values of the tbox( ) function. With this reuse, tables used in efforts to attack the encryption require much more space and computations required to find a solution are much more extensive.
The exemplary embodiment of BEVL details the use of the tbox( ) function in conjunction with the two tables t 1 box and t 2 box The resultant outputs are key-dependent permutations of the possible inputs. However, since the values of the function depend only on the key, not on the data, the function can alternatively be pre-computed for the 256 possible inputs and two possible tables with the results stored in memory. Thus a table look up can replace the reevaluation of the function. Those skilled in the art will recognize that these two methods are functionally equivalent, and will be able to make the time versus space tradeoff when employing an embodiment of the present invention. An equivalent alternative is to start with tables initialized with a permutation of the 256 possible inputs, and perform a key-dependent shuffling of those tables when the key is initialized. Then, during subsequent encryption, a table index operation would be used instead of the current calls to tbox( ), with equal effect.
The tables t 1 box and t 2 box are strict permutations, where no entry in the table is equal to its index. This strictness guarantees that there exists no key which is weaker than any other key by allowing an intermediate value in a tbox( ) computation to remain unchanged. The fact that the tables are permutations is important, as described previously in reference to function tbox( ). If the tables were not permutations, then after the table lookup in the tbox( ) function, there would be some values which could not be the result. These impossible values would allow guesses for return values from tbox( ) and parts of the key to be eliminated, reducing the work to guess the 64 bit key significantly. Alternative embodiments could employ tables which are not permutations, but the encryption would be sub-optimal.
Any form of crypt analysis of CMEA must begin by deriving values of the tbox( ) function. A complete analysis, where all outputs for the 256 possible inputs are known, allows CMEA to be applied even without knowing the initial key. However, recovery of the key is possible knowing as few as four distinct values of the function. Thus BEVL places emphasis on disguising the outputs from tbox( ) with other outputs, particularly the value of tbox( 0 ). A number of alternatives are envisioned to accomplish this disguise. The preferred embodiment uses a second different table, t 2 box, and an added pair of passes each which are performed in opposite directions. Any of these three modifications, or sub-combinations thereof, would address the problem to some extent. However, the combination of all three provides the most security.
In the preferred embodiment, the forward and backward passes use different tables, t 1 box and t 2 box, in conjunction with the tbox( ) function. This is done so that crypt analysis would require discovery of two complementary sets of function values, rather than just one set. Since the passes tend to disguise each other, two tables provide the best security. Alternative embodiments are envisioned which employ only a single table. While these methods are still secure, they are less secure than those where two tables are employed.
Begin pass 1 by proceeding from block 99 to block 102 , where variable v and buffer index i are initialized to zero. Then, in block 104 , each character buf[i] is modified by adding to itself the result of function call tbox(t 1 box, v≈i). The variable v is subsequently updated by XORing itself with the new value of buf[i]. The buffer index i is then incremented. In block 106 , if i<n, the pass is not complete and flow returns to block 104 . When all characters have been modified according to block 104 , i will equal n and pass 1 will be complete. Note that the characters were modified beginning with buf[ 0 ] working towards the end, buf[n−1].
Begin pass 2 by proceeding from block 106 to block 202 , where variable v is initialized to the value n and buffer index i is initialized to the value n−1. Then, in block 204 , each character buf[i] is modified by adding to itself the result of function call tbox(t 2 box, v≈i). The variable v is subsequently updated by XORing itself with the new value of buf[i]. The buffer index i is then decremented. In block 206 , if i≧0, the pass is not complete and the flow returns to block 204 . When all characters have been modified according to block 204 , i will equal −1 and pass 2 will be complete. Note that, unlike pass 1 , the characters were modified beginning with buf[n−1] working towards the beginning, buf[ 0 ], and the table t 2 box 14 was used instead of table t 1 box 12 .
Pass 3 begins in block 302 . Buffer index i is initialized to zero. Variable v is not used in this pass. Then, in block 304 , each character buf[i] is modified by XORing with itself the result of function call tbox(t 1 box, i+1). The buffer index i is then incremented. In block 306 , if i<n, the pass is not complete and the flow returns to block 304 . When all characters have been modified according to block 304 , i will equal n and pass 3 will be complete. Note that, like in pass 1 , the characters were modified beginning with buf[ 0 ] working towards the end, buf[n−1], and table t 1 box 12 was used. As stated before, however, the direction of pass 3 is not important, since the identical result is achieved with either direction.
In pass 3 , a different output from tbox( ) is combined with each buf[ ] entry. Because the outputs from tbox( ) form a permutation, at most only one such value can possibly be zero. Whether or not there will be a zero depends on the key. In BEVL, the change in the buffer is key-dependent and very difficult to predict. On average, the chance that one of the values will be zero is n/256, where n is the length of the buffer. Any self-inverting key-dependent or data-dependent change which guarantees that the values in the buffer will be altered is sufficient to ensure encryption. This is an important improvement for BEVL, since, in CMEA, values which remain unchanged lead to cases where the algorithm fails to encrypt at all.
Begin pass 4 by proceeding from block 306 to block 402 , where variable v is initialized to n and buffer index i is initialized to the value n−1. Then, in block 404 , a temporary variable t is assigned the value returned by the function call tbox(t 2 box, v≈i). The variable v is subsequently updated by XORing itself with the current value of buf[i]. Each character buf[i] is then modified by subtracting from itself the value of temporary variable t. The buffer index i is then decremented. In block 406 , if i≧0, the pass is not complete and the flow returns to block 404 . When all characters have been modified according to block 404 , i will equal −1 and pass 4 will be complete. Note that, like in pass 2 , the characters were modified beginning with buf[n−1] working towards the beginning, buf[ 0 ], and table t 2 box 14 was used.
Begin pass 5 by proceeding from block 406 to block 502 , where variable v and buffer index i are initialized to the value zero. Then, in block 504 , a temporary variable t is assigned the value returned by the function call tbox(t 1 box, v≈i). The variable v is subsequently updated by XORing itself with the current value of buf[i]. Each character buf[i] is then modified by subtracting from itself the value of temporary variable t. The buffer index i is then incremented. In block 506 , if i<n, the pass is not complete and the flow returns to block 504 . When all characters have been modified according to block 504 , i will equal n and pass 5 will be complete. Note that, like in passes 1 and 3 , the characters were modified beginning with buf[n−1] working towards the beginning, buf[ 0 ], and table t 1 box 12 was used.
Proceed now to block 600 . Encryption is now complete. Buf[ ] now contains the encrypted characters for secure transmission.
A “C” program implementing the operation described above is provided in FIG. 3 . Table t 1 box 12 is provided in “C” in FIG. 4 . Table t 2 box 14 is provided in “C” in FIG. 5 .
The previous description of the preferred embodiments is provided to enable any person skilled in the art to make or use the present invention. The various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without the use of the inventive faculty. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein. | In a communications system, a method of transforming a set of message signals representing a message comprising the steps of first encoding one of the set of message signals in accordance with a first keyed transformation, a second encoding of the one of the set of message signals in accordance with at least one additional keyed transformation, a third encoding of the one of the set of message signals in accordance with a self inverting transformation in which at least one of the set of message signals is altered, a fourth encoding of the one of the set of message signals in accordance with at least one additional inverse keyed transformation wherein each of the at least one additional inverse keyed transformation is a corresponding inverse of at least one additional keyed transformation, and fifth encoding the one of the set of message signals in accordance with first inverse keyed transformation wherein the first inverse keyed transformation is the inverse of the first keyed transformation. | 7 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. provisional application No. 60/684,510 filed May 25, 2005, which is herein incorporated by reference in its entirety.
BACKGROUND OF THE INVENTION
[0002] This invention relates generally to generators, and more specifically to pressure-swing-adsorption (PSA) nitrogen generators. Herein, the generators are generally referred to as nitrogen generators. However the disclosed embodiments also apply to generators of other gases, such as oxygen, methane, etc.
[0003] Nitrogen is used for many applications. The most common general application is taking advantage of its inert property, typically to keep oxygen away from combustible products or products that degrade with exposure to oxygen and/or moisture. Systems are known that utilize combusted fossil fuel to produce a mixture consisting of approximately 88% N2 and 12% CO2 for use as an inert gas. However, the presence of CO2 caused a problem for many applications. Cryogenic (approx −320F) liquid nitrogen (LN2) has became increasingly available and has replaced most of the earlier nitrogen generators. Later, pressure swing adsorption (PSA) was commercialized, making it possible to produce high purity nitrogen at facilities, including remote locations. This alleviated the need to have LN2 tanks, piping, dependence on LN2 suppliers etc. PSA also eliminated heavy losses of nitrogen product due to heat transfer, and the hazards of handling cryogenic fluid.
[0004] PSA systems use a carbon molecular sieve (CMS), which adsorbs oxygen and other molecules much more readily than nitrogen molecules. A bed of CMS in a pressure vessel is pressurized with standard compressed air. The CMS adsorbs the oxygen, while nitrogen flows through a port typically located in the opposite end from the compressed air inlet.
[0005] After a certain length of time (2 minutes for example), the CMS has adsorbed about as much oxygen as it has capacity to adsorb. At that point, the purity of the nitrogen diminishes, as more and more oxygen molecules make their way through the CMS bed to the nitrogen outlet. Typical PSA systems use two CMS adsorber vessels. Vessel ‘A’ is pressurized and producing nitrogen, while vessel ‘B’ is depressurized and “regenerated”, similar to a regenerative dessicant air dryer. After a predetermined time period, valves are switched, so that vessel ‘B’ is pressurized and produces nitrogen, while vessel ‘A’ is regenerated. This is typically controlled by electromechanical timers, or via a programmable logic controller (PLC).
BRIEF DESCRIPTION OF THE INVENTION
[0006] In one aspect, a method of operating a nitrogen generator is provided, wherein the method includes providing a source of compressed air and operating a plurality of pneumatic valves with the compressed air. The method also includes operating at least one pneumatic timer to toggle the nitrogen generator between a production mode where compressed air is channeled to a nitrogen adsorber to produce nitrogen, and a regeneration mode where substantially oxygen-rich air in the nitrogen adsorber is exhausted into the atmosphere.
[0007] In another aspect, a nitrogen generator is provided, wherein the nitrogen generator includes a source of compressed air, a plurality of pneumatic valves operated by the compressed air and configured to channel the compressed air, and a nitrogen adsorber fluidly coupled to at least one of the plurality of pneumatic valves. The nitrogen generator also includes at least one pneumatic timer to toggle said nitrogen generator between a production mode and a regeneration mode, wherein, during the production mode, the compressed air operates the plurality of pneumatic valves such that at least one pneumatic valve channels the compressed air to the nitrogen adsorber to produce nitrogen and, during the regeneration mode, the compressed air operates the plurality of pneumatic valves such that at least one pneumatic valve exhausts substantially oxygen-rich air in the nitrogen adsorber into the atmosphere.
[0008] In a further aspect, a nitrogen adsorber is provided, wherein the nitrogen adsorber includes a first end, a second end and a body extending therebetween. The body includes a carbon molecular sieve to remove oxygen from compressed air and a desiccant material to remove water from the compressed air.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is a schematic of a pneumatic control system.
[0010] FIG. 2 is a cross-sectional view of an adsorber vessel that may be used with the system shown in FIG. 1 .
[0011] FIG. 3 is an illustration of internal components of the adsorber vessel shown in FIG. 2 .
DETAILED DESCRIPTION OF THE INVENTION
[0012] Described herein are methods and apparatus that reduce cost and complexity, and improve performance, of pressure swing adsorbtion (PSA) nitrogen generators. The ability to control timing of a control system is provided with a pneumatic system that obviates the need for a programmable logic controller (PLC) or electromechanical timer, and allows operation of the system without requiring electricity. Variants of the system described herein are used for dual bed PSA systems. However the primary application is for single bed (monobed) PSA systems. Also provided is a method of constructing vessels designed for easy maintenance and low cost as is a method of obtaining quality flow distribution of gas in a space-efficient and cost-effective manner.
[0013] FIG. 1 is a block diagram of a time control system 100 . As shown in FIG. 1 , compressed air, 101 , is supplied to system 100 . A small amount of compressed air diverts to a pressure regulator 117 , which reduces pressure downstream of 117 to, for example, 80 psig. In the preferred embodiment, valve 117 is a pneumatically operated spring return valve which supplies pressure to a timer circuit when pressure is not being supplied via a pressure switch 115 . Pressure switch 115 in the preferred embodiment is a spring operated compressor unloaded valve, but may be a pneumatic or electrically operated pressure switch. When a nitrogen receiver tank 111 is “full” (at desired storage pressure), switch 115 stops applying pressure to valve 117 , and energizes the timer circuit.
[0014] Pneumatic timers 121 and 122 allow independent control of production and regeneration time for an adsorber vessel 105 . Timers 121 and 122 may be a single device, electromechanical, or other types of timers, however in the preferred embodiment timers 121 and 122 are fully pneumatic devices with an adjustable valve control dial that regulates a length of time prior to switching output.
[0015] A pulse valve 118 and a shuttle valve 119 start the system in the regeneration mode. This may be accomplished alternately by spring-loading valve 120 or other means. Adsorber 105 may be started in production cycle, however starting in the production cycle is not recommended for optimal carbon life and performance.
[0016] When valve 117 has first supplied pressure to the circuit, a pulse valve 118 supplies pressure for a small length of time (one second for example). This switches shuttle valve 119 to position A, applying pressure to valve 120 , labeled in FIG. 1 as port 14 for descriptive purposes. This passes pressure to port ‘B’ of valve 120 , applying pressure to valve 110 , which allows nitrogen to flow through, or “purge”, adsorber vessel 105 . This nitrogen purge flow is an optional feature that improves system performance. An orifice 109 is a fixed orifice in the preferred embodiment, but may also be a throttling valve or a length and diameter of tubing that will give the desired flow rate for a given system design.
[0017] The amount of nitrogen purge flow, as a function of nitrogen production, is an important variable. In one embodiment, the purge/production ratio is less than 0.05. Additional variables such as carbon molecular sieve (CMS) type, operating pressure, adsorber geometry will all affect the purge/production ratio.
[0018] The essential feature of the regeneration mode is that valve 103 is in the position that exhausts adsorber 105 contents into the atmosphere. These contents are oxygen-rich air. The oxygen and other molecules desorb from the CMS when pressure is removed. The optional flow nitrogen described above assists in flushing oxygen from the CMS.
[0019] Once the proper regeneration time has expired, for example one minute, timer 122 switches and passes air from its power port to its output port. Switching of timer 122 passes pressure to valve 120 port 12 , which allows pressure to be applied to a valve 103 . This starts the “production” cycle which allows compressed air to enter adsorber 105 . Nitrogen-rich gas flows past the CMS, through a check valve 106 , a flow control valve 107 , and a backpressure regulator 108 . When a sufficient backpressure is achieved, for example 100 psig, regulator 108 begins to open and fill nitrogen receiver 111 .
[0020] Once timer 121 switches to allow pressure to flow from power port to output port, pressure is applied to shuttle valve 119 , which switches valve 120 , initiating the regeneration cycle and the cycle repeats. This continues until pressure switch 115 reaches its setpoint, and applies pressure to valve 117 , which allows the timing circuit to exhaust and deenergize. This indicates that the nitrogen receiver is full, and stops generation of nitrogen to conserve compressed air.
[0021] A primary advantage of this system is the elimination, in the preferred embodiment, of electric power. This obviates the need for an electrician and the expense and inconvenience of wiring in typical locations. It also can allow operation in a remote site or one with non-standard voltage where a compressor is present, but possibly not a generator or supply of power. The system can safely be operated in hazardous areas where combustible gases may be present.
[0022] FIG. 2 is a schematic view of an adsorber vessel that may be used with system 100 . The vessel consists of a pipe or tube, 234 , which retains the internal pressure. The wall thickness of tube 234 is determined in accordance with well known hoop stress equations. A top head 231 and a bottom head 239 also serve to retain pressure, and are designed similarly per well known head equations.
[0023] The vessel also includes a top piping port 232 and a bottom piping port 236 . Ports 232 and 236 can be piped with normal production flow coming in the top, and flowing downward to the bottom, or reversed. In either case, flow reverses during the regeneration cycle.
[0024] A CMS bed 237 performs the separation of nitrogen and argon from other constituents in the air, which is described above. A desiccant material 238 , typically activated alumina, retains free water in the compressed air to prevent it from reaching the CMS material. Water degrades CMS and prevents oxygen from being retained. During the regeneration cycle, desiccant material 238 is also regenerated. A thin sheet of inert material 235 separates CMS bed 237 and dessicant material 238 . In one embodiment, material 235 is a fibrous mat material which is sometimes colloquially referred to as “coconut”. Components used in this construction consist of inexpensive and off-the-shelf pipe, end-caps, and clamps. Welding and costly machining is eliminated, compared to known designs.
[0025] One of the features of this monobed construction style, in addition to the use of only one vessel versus the typical use of two vessels, is the combination of CMS and desiccant in the same vessel. Known systems use a separate vessel for the desiccant. This feature significantly reduces system complexity, cost and size.
[0026] Another cost-reduction feature is the use of clamp fittings 230 that retain heads 231 and 239 . The preferred embodiment are clamp fittings used in fire sprinkler systems, manufactured by Victaulic Co., Anvil Corp. (Gruvlok™), and others. These clamp fittings use a rubber or other elastomer seal, compressed by the fitting, to provide an airtight seal, depicted by item 233 . Grooves cut or rolled into the pipe and head allow the clamp to retain the heads. These fittings provide significant cost reduction compared with the typical use of ANSI flanges. In addition, they provide a method of quick access into the contents of the adsorber vessel, reducing labor during fabrication and maintenance operations. ANSI flanges take many more large bolts (typically 4, 8, 12, 16 or more bolts per closure). Typically desiccant must be changed every 3-4 years, while the CMS can last a decade or more. The clamps also typically have a smaller diameter than ANSI flanges, allowing more compact system packaging.
[0027] Another feature described herein is the placement of desiccant 238 on top of CMS bed 237 . The placement of desiccant allows the more frequent changing of the desiccant material to be performed without disturbing the CMS or removing the adsorber vessel. The desiccant is typically removed utilizing a vacuum device. Conversely it is possible to turn the vessel over from the preferred orientation and remove the CMS while leaving desiccant intact, on the less frequent occasions where this is necessary.
[0028] An additional benefit of this construction is that there is not a requirement for welding. This allows fabrication without the need for a welding machine or operator. It also obviates the need for welding qualifications and inspection of welds and certain construction codes. These aspects significantly reduce construction costs.
[0029] FIG. 3 is a close-up cross-section of the head region illustrated in FIG. 2 . Item 344 is the clamp, and 343 is the head. Item 340 is a thick section of the previously described “coconut” material (or other inert material). This material serves as a gas-distribution system, allowing the material to distribute evenly across the cross-sectional area without excessive pressure drop. The means presently known in the field typically involve a complex assembly of metal standoffs and perforated fabricated assemblies. These other designs typically use a much more significant volume. The embodiments disclosed herein, by comparison, improve air consumption efficiency.
[0030] Still referring to FIG. 3 , a mesh screen 342 prevents CMS and/or desiccant material from flowing into the process piping, which would cause damage to other components, and degradation of the adsorber performance. Item 341 is a perforated plate with holes larger than screen 342 . Plate 341 is typically sheet metal, but may be of plastic or other materials. Items 341 and 342 may be a single device with perforations. However, it is believed that the use of two devices lends to superior performance, where item 342 catches fine particles, but item 341 blocks larger particles, helping to keep screen 342 from clogging. Item 341 is firmly attached to head 343 , by tack-welding, screws, rivets, or other common means.
[0031] The primary result of the embodiments described herein is the production of a low-cost efficient means for producing nitrogen. The means disclosed herein greatly reduce the cost of producing systems with small capacity. There are many markets with a need for low cost, reliable units. These include tire inflation, food preservation (displacing oxygen which degrade food), beverage production, especially alcohol, beverage dispensing, blanketing of tanks that have chemicals and petroleum products, and many others. In addition, the embodiments described herein enables nitrogen generators to be effective and productive in many more markets by reducing costs and eliminating the requirement for electrical power.
[0032] As used herein, an element or step recited in the singular and proceeded with the word “a” or “an” should be understood as not excluding plural said elements or steps, unless such exclusion is explicitly recited. Furthermore, references to “one embodiment” of the present invention are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features.
[0033] Although the apparatus and methods described herein are described in the context of a carbon molecular sieve (CMS) and a pressure-swing-adsorption (PSA) nitrogen generator, it is understood that the apparatus and methods are not limited to CMS or PSA nitrogen generators. Likewise, the CMS and PSA nitrogen generator components illustrated are not limited to the specific embodiments described herein, but rather, components of the CMS and PSA nitrogen generator can be utilized independently and separately from other components described herein.
[0034] While the invention has been described in terms of various specific embodiments, those skilled in the art will recognize that the invention can be practiced with modification within the spirit and scope of the claims. | A method of operating a nitrogen generator is provided, wherein the method includes providing a source of compressed air and operating a plurality of pneumatic valves with the compressed air. The method also includes operating at least one pneumatic timer to toggle the nitrogen generator between a production mode where compressed air is channeled to a nitrogen adsorber to produce nitrogen, and a regeneration mode where substantially oxygen-rich air in the nitrogen adsorber is exhausted into the atmosphere. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Application No. 60/727,755, filed on Oct. 18, 2005. The disclosure of the above application is incorporated herein by reference.
BACKGROUND AND SUMMARY OF THE INVENTION
[0002] The present invention generally relates to cutting tools and, more particularly, to an apparatus and method for masking and coating cutting tools.
[0003] Many vehicle drivelines include power transmission devices having a number of gears in meshing engagement with one another. Each gear typically includes a plurality of teeth spaced apart from one another to properly mesh with the teeth of another gear. Each gear tooth must be precisely formed to provide reliable power transmission over an extended period of time.
[0004] The gears are constructed using gear cutting tools operable to remove material from a gear blank to define the gear teeth. In high volume manufacturing, it is desirable to quickly and accurately cut the gear teeth into a desired finished shape. It is also desirable to minimize the costs associated with constructing such gears. Accordingly, tooling design engineers strive to define manufacturing processes where not only the finished gear is constructed according to specification but where the cutting tools remain sharp for extended periods of time. A number of cutting tool manufacturers have constructed cutting tools from high speed steel, tungsten carbide and other cutting materials. In one instance, tool life has been extended by coating a tungsten carbide tool with a wear resistant material such as titanium aluminum nitride (tialn). Titanium nitride (tin) may be used as a coating for high speed steel applications. The coating is typically applied by immersing the tool in an environment containing a mixture of gas including tialn or tin for six to eight hours. During exposure to the gas mixture, a coating is deposited on all surfaces exposed to this environment. Cutting tools exposed to this process have exhibited up to double the cutting life of similar tools not coated with the wear resistant material.
[0005] Once a cutting tool has become dull, it is common practice to grind the tip of the cutting tool to sharpen and/or redefine the cutting edge or edges. Unfortunately, the grinding process removes the coating previously applied to the cutting surfaces. Typically, the entire tool is exposed to the coating process once again to assure that the recently ground surfaces are coated. Because not all of the cutting tool is ground during the sharpening process, most of the cutting tool receives an additional coating thickness of the wear resistant material. It has been found that this grinding and recoating process may be repeated approximately five times until an undesirable result occurs. Specifically, once five or more layers of the coating are accumulated on the non-ground surfaces, the coating no longer properly adheres and causes the tool to fail.
[0006] It has been contemplated to remove the coating from the entire cutting tool prior to recoating using a chemical process. The chemical process negatively affects the cutting tool by removing the Cobalt from the cutting tool surface. The carbide microstructure is adversely altered and no longer exhibits the excellent cutting properties for which the tool is designed.
[0007] Alternately, it has been contemplated to machine more surfaces of the cutting tool to remove the previous coatings prior to reapplying another coating to the reground cutter. Unfortunately, the additional machining processes are very costly and may negatively interfere with the geometry of the cutting tool and repeatability of the machining operation. Accordingly, a need exists for a method of sharpening and recoating a cutting tool to extend the interval between cutting tool sharpening operations and to increase the number of times a given tool may be sharpened.
[0008] The present invention provides an apparatus and method of masking and coating a cutting tool. The method includes mounting a plurality of cutting tools in a holder, aligning a mask to cover a predetermined portion of each cutting tool, mounting the mask to one of the cutting tools and the holder, exposing uncovered portions of each cutting tool to an environment containing a depositable material and forming a coating on the uncovered portions of each cutting tool.
[0009] A fixture for mounting and masking cutting tools includes a tool holder and a mask. The tool holder has a cavity adapted to receive a plurality of cutting tools. The mask is coupled to the holder and aligned with the plurality of cutting tools where a majority of the surface area of each cutting tool is covered by the tool holder and the mask. The mask includes a shaped portion having a profile adapted to substantially match the profile of the shaped cutting tip for the cutting tool. The mask is positioned to expose a portion of the cutting tool to the surrounding atmosphere.
[0010] Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein:
[0012] FIG. 1 is perspective view of an exemplary cutting tool;
[0013] FIG. 2 is an exploded perspective view of a fixture operable to hold and mask cutting tools during a coating process;
[0014] FIG. 3 is a top view of a portion of the fixture illustrated in FIG. 2 having a plurality of cutting tools positioned therein;
[0015] FIG. 4 is an end view of the fixture illustrated in FIG. 2 having a plurality of cutting tools positioned therein;
[0016] FIG. 5 is a partial fragmentary plan view of a portion of a cutting tool and a portion of a mask positioned on the cutting tool; and
[0017] FIG. 6 is an exploded perspective fragmentary view illustrating alternate embodiment masks.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0018] The following description of the preferred embodiments is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses.
[0019] FIG. 1 depicts an exemplary cutting tool 10 operable to remove material from a gear blank and form a portion of the gear teeth. Typically, cutting tools are arranged in pairs where the first tool of the pair removes material from one side of the “V-shaped” groove and the other tool having an opposite hand removes material from the opposite side of the same “V-shaped” groove. Depending on the gear to be manufactured, many pairs of cutting tools may be mounted to a cutting head (not shown) to form a gear.
[0020] Cutting tool 10 is formed from an elongated bar of tungsten carbide having a rectangular cross-section. Cutting tool 10 includes a gripping portion 12 having a width 14 and height 16 . Gripping portion 12 maintains a substantially rectangular cross-section. Gripping portion 12 includes a top face 18 . A cutting tip 20 is formed at an opposite end of cutting tool 10 from gripping portion 12 . Cutting tip 20 is formed by machining a cutting face 22 at a 12° angle to top face 18 . Cutting tip 20 includes a first side 24 and a second side 26 . The first and second sides 24 , 26 terminate at a rounded root cutting portion 28 . The intersection of cutting face 22 and first side 24 forms a cutting edge 30 operable to remove material from the gear blank. Second side 26 is shaped to provide clearance for the opposite hand cutting element (not shown) paired with cutting tool 10 . An edge 32 formed at the intersection of cutting face 22 and second side 26 does not typically remove any material from the gear blank.
[0021] As previously described, after a number of gears have been cut, cutting edge 30 dulls. At this time, cutting tool 10 is removed from the gear cutting apparatus and sharpened. During sharpening, the cutting tool is ground along first side 24 , second side 26 and rounded root cutting portion 28 . The grinding forms a sharpened cutting edge 30 . After cutting tool 10 has been sharpened, first side 24 , second side 26 and rounded root cutting portion 28 will no longer be coated by the previously deposited wear resistant coating. Accordingly, sharpened cutting tools are prepared to be exposed to an environment within an enclosed chamber (not shown) to coat cutting edge 30 , first side 24 , second side 26 and rounded root cutting portion 28 with the wear resistant material.
[0022] After sharpening, cutting tool 10 is thoroughly cleaned to remove any dirt, oil or metal shavings from the surfaces of the cutting tool 10 . A single sharpened cutting tool 10 or a number of sharpened cutting tools similar to cutting tool 10 are next placed in a fixture 100 illustrated in FIGS. 2-4 . Fixture 100 is operable to accurately align a number of cutting tools relative to one another and mask a majority of the external surfaces of the cutting tools from exposure to an environment containing a wear resistant coating. Fixture 100 is sized to support the cutting tools 10 in the enclosed chamber having a mixture of gases and tialn and/or tin coating circulating throughout the chamber. The surfaces exposed to the environment within the chamber are coated with a predetermined thickness of wear resistant material based on the time of exposure to the environment in the chamber.
[0023] To assure that less than five thicknesses of wear resistant coating are present on cutting tip 20 at any one time, fixture 100 is sized and shaped to expose only a very limited portion of each cutting tool 10 to the environment within the chamber. Specifically, the surface area of cutting tool 10 exposed to the environment corresponds to the quantity of cutting tool 10 that is removed during the grinding and/or sharpening processes. FIG. 5 depicts the amount of cutting face 22 exposed after mounting and masking the cutting tools 10 within fixture 100 . In this manner, only one or two thicknesses of wear resistant coating are on cutting edge 30 at any one time. By maintaining a proper thickness of wear resistant coating, tool life is greatly extended.
[0024] Fixture 100 includes a shell 110 , a cover 112 and a mask 114 . Shell 110 is a substantially “U” shaped member having a first side wall 116 , a second side wall 118 and an end wall 120 interconnecting the side walls 116 , 118 . End wall 120 includes a substantially planar top surface 122 extending between first side wall 116 and second side wall 118 . First side wall 116 includes a substantially planar upper surface 124 . Second side wall 118 includes a substantially planar upper surface 126 . Upper surface 124 and upper surface 126 are substantially co-planar with one another. Threaded apertures 128 extend transversely through first side wall 116 . Threaded bores 130 are positioned in first side wall 116 and extend through upper surface 124 . Threaded bores 132 are positioned within second side wall 118 . Bores 132 extend through upper surface 126 of second side wall 118 .
[0025] Cover 112 is substantially shaped as a plate having a hat-shaped cross-section. Cover 112 includes a body portion 134 and laterally extending flanges 136 . Flanges 136 include lower surfaces 138 . Body portion 134 includes a lower surface 140 . Apertures 142 extend through the thickness of cover 112 . Apertures 142 are sized and positioned to receive threaded fasteners 144 . Threaded fasteners 144 threadingly engage bores 130 and bores 132 formed in shell 110 . Fasteners 144 are operable to clamp cutting tools 10 and mask 114 between top surface 122 of end wall 120 and bottom surface 140 of cover 112 .
[0026] Mask 114 is a plate-like structure having a plurality of teeth 150 formed at one end. Each tooth 150 includes a first face 152 and a second face 154 interconnected by a rounded end 156 . First face 152 , second face 154 and rounded end 156 are shaped substantially similarly to first side 24 , second side 26 and rounded root cutting portion 28 of cutting tip 20 . Furthermore, each tooth 150 is spaced apart a distance equivalent to the spacing between adjacent cutting tips 20 of cutting tools 10 when positioned adjacent to one another. As best illustrated in FIG. 4 , each tooth 150 includes an angled back face 158 positioned to engage one of the cutting faces 22 formed on each cutting tool 10 .
[0027] After the individual cutting tools 10 have been sharpened, a number of cutting tools 10 are positioned within shell 110 . Cutting tips 20 are aligned along a common plane and then cutting tools 10 are mounted to shell 110 using a pair of threaded fasteners 160 . Threaded fasteners 160 are threadingly engaged with apertures 128 and protrude through first side wall 116 to engage one of the cutting tools positioned within shell 110 . A compressive load is placed on each of the cutting tools 10 via threaded fasteners 160 to secure the cutting tools 10 within the shell 110 .
[0028] One skilled in the art will appreciate that any number of manufacturing techniques may be used to align cutting tips 20 along the common plane. For example, a cap 200 may be temporarily coupled to shell 110 to provide a datum surface 202 on which each of the cutting tools 10 are abutted prior to clamping cutting tools 10 to shell 110 . Specifically, cap 200 is a substantially “C” shaped member having a wall 204 interconnecting a first leg 206 and a second leg 208 . First leg 206 includes an aperture 210 extending therethrough for receipt of a fastener 212 . Fastener 212 is threadingly engageable with an aperture 214 formed in first side wall 116 . Similarly, second leg 208 includes an aperture 216 for receipt of another fastener 212 threadingly engaged with an aperture 218 formed in second side wall 118 . Datum surface 202 is formed on wall 204 and spaced apart a predetermined distance “B” from an end surface 230 of shell 110 .
[0029] Cap 200 may also be used to properly position mask 114 relative to the cutting tools 10 . Alternatively, mask 114 may include a key or a pin (not shown) to align mask 114 relative to shell 110 at a predetermined location. Because teeth 150 of mask 114 are similarly shaped to cutting tips 20 of cutting tool 10 , mask 114 is axially offset from the plurality of cutting tools 10 such that teeth 150 formed on mask 114 do not completely cover the entire cutting face 22 of each cutting tool 10 . As illustrated in FIG. 5 , rounded end 156 is offset from rounded root cutting portion 28 by a predetermined distance. In the example shown, the predetermined distance is 1 mm. It should be appreciated that this distance may vary depending on the amount of cutting tool 10 that must be removed during each grinding or sharpening process. Furthermore, because rounded end 156 is offset from rounded root cutting portion 28 , a portion of cutting face 22 adjacent cutting edge 30 and edge 32 is exposed to atmosphere. Based on the orientation of the components previously described, each cutting tool 10 will receive a coating of wear resistant material on first side 24 , second side 26 , rounded root cutting portion 28 , cutting edge 30 , edge 32 and a relatively small portion of cutting face 22 .
[0030] Once the positioning of cutting tool 10 and mask 114 is completed, fasteners 144 interconnect cover 112 and shell 110 to clamp cutting tools 10 and mask 114 therebetween. The subassembly of cutting tools 10 and fixture 100 are placed within an enclosed vessel and the portions of each of the cutting tools 10 exposed to atmosphere are coated with a predetermined thickness of wear resistant material.
[0031] Upon completion of the sharpening and coating processes, the cutting tools 10 are mounted to a cutting head and used to manufacture gears once again. Once the cutting tools 10 are dull, the tools are removed and the sharpening and coating processes are repeated. It should be appreciated that the external surfaces of cutting tools 10 that were previously coated are now removed during the sharpening process. Therefore, an undesirable amount of wear resistant coating is not accumulated at any time through tool life.
[0032] An alternate embodiment mask assembly 300 is depicted at FIG. 6 . A plurality of masks 302 are used in conjunction with shell 110 . Each mask 302 is shaped substantially similar to the cutting end of a cutting tool 10 . Each mask 302 is positioned substantially similarly as teeth 150 were positioned relative to cutting tips 20 in the previous embodiment. It is contemplated that masks 302 may be used in place of mask 114 and vice versa.
[0033] Furthermore, the foregoing discussion discloses and describes merely exemplary embodiments 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 may be made therein without departing from the spirit and scope of the invention as defined in the following claims. | A fixture for mounting and masking cutting tools includes a tool holder and a mask. The tool holder has a cavity adapted to receive a plurality of cutting tools. The mask is coupled to the holder and aligned with the plurality of cutting tools where a majority of the surface area of each cutting tool is covered by the tool holder and the mask. The mask includes a shaped portion having a profile adapted to substantially match the profile of the shaped cutting tip for the cutting tool. The mask is positioned to expose a portion of the cutting tool to the surrounding atmosphere. A method of masking and coating a cutting tool is also presented. | 2 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit under 35 U.S.C. §119 of United Kingdom Patent Application Serial No. 0508809.1, filed May 3, 2005, and entitled “Device and Saddle Assembly,” the disclosure of which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a device for breaking the fall of a rider from a horse or the like and a saddle assembly including a saddle equipped with such a device and a method for horse riding.
[0004] 2. Description of the Related Art
[0005] Horse riding is a popular sport, but can be inherently dangerous if a horse unseats a rider, or the rider loses balance and falls from the horse. Serious injuries can result from such falls, particularly back and head injuries. It is generally accepted that riders should not be secured to animals to prevent them from falling, as this could be dangerous for the rider in the event that they lose control of the animal and it bolts under low lying branches for example, or if the rider is dragged behind the animal. Thus, riders are typically taught to let go and fall from a horse cleanly when they lose balance or when the horse bolts.
SUMMARY OF THE INVENTION
[0006] According to a first exemplary aspect of the present invention there is provided a device for breaking a fall of a rider from a horse or the like, the device comprising at least one member having a first end portion and a second end portion, wherein the first end portion is connectable to a load bearing portion of a saddle and wherein the second end portion is capable of being gripped by a rider. In such an embodiment, either or both members can be a flexible member.
[0007] The device provides an aid for riders who fall from a horse or the like and enables the rider to make a more controlled and safer descent. In the event of a fall from an animal, use of the device enables the rider to maintain a semi-upright position. Since the second end portion is capable of being gripped by a rider, the head and back of the rider are more likely to be clear from the ground and the rider will be landed over the shoulder of the horse, which is safer.
[0008] The first end portion of either or both members can be arranged to be coupled to load bearing portions of the saddle at spaced apart locations.
[0009] The first end portion can be provided with connection means for connecting the device to the load bearing portion of the saddle.
[0010] The connection means can comprise two connectors for connecting the first end portion to the saddle in two separate locations. Thus the device can comprise one member and two connectors arranged in a Y-shaped configuration.
[0011] The first end portion connectable to the saddle is advantageous since any load applied to the device in use will be borne in a mid region on the back of the horse or the like.
[0012] Each connector can comprise a length of webbing. A smooth webbing material is advantageous since it will limit any pain experienced by the horse or the like if the webbing material comes into contact with the animal.
[0013] Each connector can comprise a fixing means. The fixing means can comprise an anchor tie for fixing the device to the load bearing portion of the saddle.
[0014] Each connector can be connectable to two load bearing portions of the saddle. The connectors can further comprise one or more links for coupling each member to the saddle in use, wherein the links are arranged to break on application of a predetermined force thereto.
[0015] Accordingly, these links are provided to act as sacrificial links in use, to dissipate some of the energy of the fall, since they are designed to break on application of a predetermined force. Therefore, when the device is in use, the links coupling the device and the saddle can be used to weaken the impact or force of the fall.
[0016] At least one member can be provided with a stop member. The stop member can comprise a rim protruding radially outwardly with respect to the or each member. The stop member can be arranged such that it is proximate to the second end portion. The stop member can be arranged to act as an impediment to prevent the device from slipping out of the rider's hand when in use.
[0017] A compressible member can be provided on the member, preferably in the region of the second end portion. The compressible member can be compressible by a rider, thereby acting as a shock absorber. Preferably the compressible member is compressible in an axial direction, the axial direction defined by the member.
[0018] A neck portion of the compressible member may be provided to encourage the compression of the compressible member, the neck portion having a smaller radius than a main part of the compressible member. The width and/or length of the neck portion can be varied to alter the compressive force required for deformation thereof. In general, the shorter axial length of the neck portion the less force required for compression and the longer axial length of the neck portion, the greater the force required for compression thereof.
[0019] Preferably, the compressible member is adapted to compress to a greater extent than the member. Preferably, the member is adapted to compress by a negligible extent.
[0020] The compressible member can comprise two or more portions, each shaped to compress on application of a predetermined load. The portions can be shaped to compress on application of different predetermined loads. Each shaped portion can comprise a neck portion.
[0021] The compressible member can be manufactured from compressible foam rubber.
[0022] The stop member can be provided as part of the compressible member, such that application of a force to the stop member causes compression of the compressible member, typically in an axial direction.
[0023] Preferably, the compressible member comprising the stop member has a bore through which the member extends.
[0024] The device can comprise two members provided adjacent each other which connect with at least one, preferably two pairs of adjacent connectors, each pair of connectors connectable to the saddle, such that in use, the connection between one member and the saddle will not be broken should another member or one connector break.
[0025] The length of each member can be adjustable. Each member can be provided with adjuster means. Thus the length of the device can be altered to suit the requirements of the rider or the nature of the riding they intend to do.
[0026] The device can be manufactured from synthetic rope.
[0027] According to a second exemplary aspect of the present invention, there is provided a saddle assembly comprising a saddle and a device for breaking a fall of a rider as described herein.
[0028] The saddle assembly is useful in conjunction with the usual horses tack. Reins are typically provided to be held by the rider for controlling the horse. However, the reins are not load bearing and move with the horse's head. The saddle assembly comprising the device attached to the saddle, is a separate, steady aid for a rider. Attaching the device to a load bearing portion of the saddle is advantageous as it represents the most stable position for the device and is likely to be the least damaging to the horse. The device is suitable for attachment to a standard English saddle.
[0029] Connector means can connect the member to load bearing portions of the saddle in spaced apart locations. Connector means preferably connect the member to stirrup bars provided on the saddle.
[0030] Two members can be coupled to the saddle in two spaced apart locations.
[0031] The device coupled to the saddle at two spaced apart locations can occupy a Y-shape. This has the advantage that when a rider falls, the horse carries a certain amount of the strain on its back without a part of the saddle to which the device is attached, such as the stirrup bar, from taking all the load of the falling rider.
[0032] The device can also be used to allow a rider to regain their balance. The device can also be used to allow a rider to control their descent on dismounting from the horse or the like.
[0033] The device is not limited to use on a horse, as it may be used on other animals such as a donkey, pony, etc.
[0034] The invention also provides a method of horse riding comprising gripping a device as described herein whilst riding.
[0035] The invention also provides a method for a rider to control a fall from a horse or the like, the method comprising the rider holding a device as described herein, the device being secured to a load bearing portion of a saddle on the horse, and in the event of the rider falling from the horse, maintaining hold of the device, allowing the device to take a portion of the weight of the rider, and releasing the device.
[0036] Preferably the method includes compressing the compressible member in order to cushion the fall, and more preferably allowing the sacrificial weak links to break before releasing the device.
[0037] Preferably the device also aids to orient the rider so that their head is uppermost and preferably so that they are less likely to land on their back or head.
[0038] Any feature of any aspect of any invention or embodiment described herein may be combined with any feature of any aspect of any other invention or embodiment described herein mutatis mutandis.
BRIEF DESCRIPTION OF THE DRAWINGS
[0039] Embodiments of the present invention will now be described with reference to and as shown in the following drawings:
[0040] FIG. 1 is a top view of a device according to the first aspect of the present invention;
[0041] FIG. 2 is a top view of the device according to another embodiment of the first aspect of the present invention;
[0042] FIG. 3 is a side perspective view of a saddle assembly according to the second aspect of the present invention;
[0043] FIG. 4 is a side view of a shock absorber; and
[0044] FIG. 5 is a side perspective view of a saddle assembly according to a further embodiment of the present invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0045] The exemplary embodiments of the present invention are described and illustrated below to encompass devices for breaking the fall of a rider from a horse or the like and a saddle assembly including a saddle equipped with such a device and a method for horse riding. Of course, it will be apparent to those of ordinary skill in the art that the preferred embodiments discussed below are exemplary in nature and may be reconfigured without departing from the scope and spirit of the present invention. However, for clarity and precision, the exemplary embodiments as discussed below may include optional steps, methods, and features that one of ordinary skill should recognize as not being a requisite to fall within the scope of the present invention.
[0046] A device for breaking the fall of a rider (not shown) from a horse or the like is shown generally at 10 in FIGS. 1-3 .
[0047] The device 10 of FIG. 1 comprises a flexible member 12 and connectors 14 . The flexible member 12 has a first end portion 92 and a second end portion 94 that may be comprised of a synthetic rope, such as polyester.
[0048] Towards the second end portion 94 there is provided a hand stop 18 in the form of a rim extending radially outwardly relative to the flexible member 12 . Similarly, an end stop 22 is provided in the form of a rigid rim extending radially outwardly and is prevented from sliding off the flexible member 12 by a knot 24 . The hand stop 18 also comprises a shock absorber 20 . The shock absorber 20 is positioned between the hand stop 18 and the end stop 22 . According to this embodiment, the shock absorber 20 comprises a compressible foam rubber. Although, any form of compression device or material capable of deformation will be suitable for use as the shock absorber 20 .
[0049] The first end portion 92 is tied to a metal ring 50 . Also attached to the metal ring 50 are two strips of webbing 30 . Each length of webbing 30 is attached to the ring 50 by means of a doubled over end portion 34 which is stitched to form an aperture (not shown). The aperture accommodates the metal ring 50 . Similarly, an opposing end portion 32 is doubled over and stitched to create an aperture (not shown), which accommodates a spring-loaded clip 38 . The spring-loaded clip 38 is provided with an anchor line 40 and a link 42 attached thereto. The anchor line 40 and the link 42 can be used for coupling the device 10 to a saddle. The anchor line 40 is attached to a load bearing portion of a saddle whereas the link 42 is attached to any suitable part of the saddle, as described in more detail below.
[0050] The device shown in FIG. 2 is similar to the FIG. 1 embodiment, but comprises two flexible lines 12 A and 12 B. Each line 12 A, 12 B is provided with a hand stop 18 A, 18 B, shock absorber 20 A, 20 B and end stop 22 A, 22 B towards the second end portion 94 as described for FIG. 1 above. Flexible lines 12 A, 12 B are coupled in adjacent relation using ties 56 .
[0051] At the first end portion 92 the flexible lines 12 A, 12 B are each provided with a separate D-ring 52 A, 52 B. The D-rings 52 A, 52 B are joined by a tie 54 . The connectors 14 are the same as those previously described for FIG. 1 .
[0052] The advantage of the system such as that shown in FIG. 2 is that in the event of failure or breakage of any of the attachments coupling the device 10 to a saddle, there is an in-built system redundancy since there are effectively two devices independently attached at separate points to load bearing portions of the saddle. As shown in FIG. 2 these are coupled together to facilitate use of the device by the rider, while providing the system with in-built redundancy.
[0053] FIG. 3 shows a saddle indicated generally at 60 with the device 10 attached thereto by connectors 14 . The saddle 60 has a seat portion 61 and is provided with two stirrup bars 62 secured to opposing sides of the saddle 60 on either side of the seat portion 61 . The stirrup bars 62 are C-shaped and have leather straps 64 slotted therein for supporting stirrups 68 . In use, each stirrup 68 accommodates a foot of the rider. Thus, each stirrup bar 62 to which the stirrup 68 is attached via the leather strap 64 is necessarily a load bearing part of the saddle 60 .
[0054] Another advantage of the device 10 is that it can be used in conjunction with a traditional English saddle without modification thereof. As well as being load bearing portions of the saddle 60 , the stirrup bars 62 are also adapted to cope with jolts experienced when a rider mounts a horse.
[0055] The device 10 shown in FIG. 3 comprises a flexible line 72 which is provided with a ball stop adjuster 74 for adjusting the length of the line 72 . The anchor ties 40 secure the device 10 to the saddle 60 . Each anchor tie 40 attaches directly to the corresponding stirrup bar 62 . Links 42 are used to attach the spring-loaded clips 38 to D-rings 66 , which D-rings 66 are fixed to the saddle 60 .
[0056] The ties 40 and the links 42 used in the present embodiment are advantageous since they do not require modification of a standard English saddle 60 . D-rings 66 are commonly provided on saddles. However, any other appropriate form of attachments or connectors 14 can be used.
[0057] Before use, the length of the flexible line 72 can be adjusted depending on the requirements of the rider. Adjustment of the flexible line 72 is achieved using the ball adjuster 74 .
[0058] The rider can mount the saddle 60 in the usual manner and sit in the seat portion 61 , while the rider's feet are accommodated in the stirrups 68 . It is usual for the rider to hold reins (not shown) for controlling the movement of the horse or other animal. Notably, the reins are never attached to a load bearing part of the horse. The rider also holds the flexible member 72 in one hand.
[0059] In the event that the rider is dislodged from the seat portion 61 and begins to fall from the saddle 60 , they can grasp firmly the device 10 in the region of the second end portion 94 of the flexible line 72 . This is in contrast with the general teaching that a rider should let go as soon as they start to fall from an animal. The line 72 is more stable than the reins as the device 10 is attached to load bearing portions of the saddle 60 in a mid portion of the horse, whereas the reins are attached to, and therefore move with, the horses head.
[0060] If the rider's grip on the flexible member 72 slips as the rider falls, the rider's clenched hand will eventually abut the hand stop 18 . The hand stop 18 prevents the device 10 from slipping out of the rider's grasp altogether. As the rider's hand abuts the hand stop 18 , the shock absorber 20 between the hand stop 18 and end stop 22 will be at least partially compressed, thereby cushioning the rider's hand from a jolt experienced as the impact of the falling rider is taken up by the device 10 as it becomes taut, which reduces some of the initial impact of the fall.
[0061] Once sufficient force is applied to the connector means 14 , for example, when the device 10 becomes taut, the links 42 attaching the spring loaded clip 38 to the D-ring 66 are arranged to break, further cushioning the fall of the rider and dissipating some of the energy associated with the fall.
[0062] Since the rider is holding onto the device 10 , their body will tend to orientate during the fall so that their head is further from the ground than their legs or lower part of their body. This will also bring their back upright.
[0063] The rider can then let go of the device 10 and fall to the ground.
[0064] The device 10 allows a rider to fall in a graduated and controlled manner. The shock absorber 20 and sacrificial links 42 alleviate the sudden impact of the fall experienced by the hand and body of the rider. The hand stop 18 and material from which the flexible member 72 is manufactured can improve the rider's purchase on the device 10 . The act of holding on to the device 10 maintains the rider's head and neck, at least partially upright and prevents the rider from falling head first from the horse.
[0065] A further advantage of the Y-shaped attachment when the device is coupled to the saddle as shown in FIG. 3 , is that as the rider falls on one side of a horse, the webbing 30 of the connector means 14 is taut on the opposing side, thereby ensuring that the anchor tie 40 , is acting on a central section of the C-shaped stirrup bar 62 . This is achieved without the anchor tie 40 tending to slip off the stirrup bar 62 as the rider falls, which may be the case if the connectors 14 were not constrained on both sides of the seat portion 61 of the saddle 60 . Additionally, the Y-shaped arrangement allows the horse's back to carry a proportion of the strain, so that it is not all carried by the stirrup bar 62 .
[0066] The symmetrical nature of the Y-shaped attachment is advantageous since the device 10 defines an identical locus on each side of the saddle 60 within which it operates as a rider falls. Therefore the length of the device 10 can be accurately determined to suit the height of the rider. Alterations or adjustments to compensate for riders of a different weight and/or height are facilitated since the device 10 can be adjusted once to obtain an equal locus in which it operates on either side of the saddle 60 .
[0067] The device 10 is designed not only to be weight bearing but is also designed with the ability to withstand the sudden impact when a rider falls. Furthermore, since the device 10 is attached to a load-bearing portion of the saddle 60 , the device is very stable and reliable. Additionally, placement of the device 10 on a load bearing portion of the saddle 60 means that the rider will tend to fall behind the shoulder portion of the horse when using the device 10 . This is safer for the rider as it reduces the risk of being trampled by the horse.
[0068] An alternative shock absorber 20 s is shown in FIG. 4 with a hand stop 118 and an end stop 122 at respective ends thereof. The shock absorber 20 s is provided with an axial throughbore (not shown) through which the member 12 , 12 A, 12 B, 72 is accommodated. The shock absorber 20 s is formed with a first shaped portion A and a second shaped portion B. Portion A has a narrow neck region 80 between an outer circumference 78 and an outer circumference 82 . Portion B has a graduated neck region 84 between the outer circumference 82 and an outer circumference 86 . Due to the narrow neck region 80 of the portion A, a smaller force is required to at least partially compress the neck region 80 between the outer circumference 78 and the outer circumference 82 , than that required to compress the more graduated neck region 84 . Thus, on application of a compressive force to the shock absorber 20 s , the portion A initially at least partially compresses, while application of a greater force is required to at least partially compress portion B. As a result, the impact of the fall can be reduced in two stages; first by compression of portion A, followed by compression of portion B if sufficient force is applied. Thus, the graduated neck region 84 is arranged to cope with severe shocks and jolts.
[0069] In FIG. 5 , an inertia reel 190 is provided on a device 100 to allow the rider to pull out a required length of the flexible member 112 . If the rider intends to jump with the horse then a longer length may be chosen compared to purely flat work with the horse which would ideally require a shorter length. In use, the inertia reel 190 will stop further extraction of the flexible member by known internal mechanisms. Inertia reels are available from a number of suppliers, for example: Lifting and Safety Services, Scunthorpe, UK; Warwick and Associates, Arizona, USA and Beaver Sales Pty Ltd, NSW, Australia. Other components shown in FIG. 5 , including a shock absorber 120 , webbing 130 and a ring 150 (sewn into the webbing) have a similar use as that described for earlier embodiments.
[0070] Modifications and improvements can be made without departing from the scope of the invention. For example an automatic release mechanism may be incorporated. This may be in the form of a further weak link which would break should an unseated rider be caught between a horse and some other immovable object and still try to hold on. However this is less preferred since the “weak” link would still need to be strong enough to cushion the fall of a rider. Alternatively the automatic release may be facilitated by a position release mechanism, for example by use of a slotted mechanism, which releases the device from the horse when in an orientation which corresponds with the rider having fallen from the horse.
[0071] Following from the above description and invention summaries, it should be apparent to those of ordinary skill in the art that, while the methods and apparatuses herein described constitute exemplary embodiments of the present invention, the invention contained herein is not limited to this precise embodiment and that changes may be made to such embodiments without departing from the scope of the invention as defined by the claims. Additionally, it is to be understood that the invention is defined by the claims and it is not intended that any limitations or elements describing the exemplary embodiments set forth herein are to be incorporated into the interpretation of any claim element unless such limitation or element is explicitly stated. Likewise, it is to be understood that it is not necessary to meet any or all of the identified advantages or objects of the invention disclosed herein in order to fall within the scope of any claims, since the invention is defined by the claims and since inherent and/or unforeseen advantages of the present invention may exist even though they may not have been explicitly discussed herein. | A fall arrestor suitable for attachment to a saddle. The fall arrestor is held by a rider of a horse or the like and allows the rider to control and mitigate the danger when unseated from a horse. Exemplary embodiments include webbing configured in a Y-shape so that it can be connected to stirrup bars on opposite sides of a saddle which conveniently take the load of a fall. The device may also include sacrificial links and a rubber shock absorber to further control the fall. | 5 |
FIELD OF THE INVENTION
The present invention is directed to probe structures for testing of electrical interconnections to integrated circuit devices and other electronic components and particularly to testing integrated circuit devices with high density areas array solder ball interconnections at high temperatures.
BACKGROUND OF THE INVENTION
Integrated circuit (IC) devices and other electronic components are normally tested to verify the electrical function of the device and certain devices require high temperature burn-in testing to accelerate early life failures of these devices. Wafer probing is typically done at temperatures ranging from 25 C.-125 C. while typical burn-in temperatures range from 80 C. to 140 C. Wafer probing and IC chip burn-in at elevated temperatures of up to 200 C. has several advantages and is becoming increasingly important in the semiconductor industry.
The various types of interconnection methods used to test these devices include permanent, semi-permanent, and temporary attachment techniques. The permanent and semi-permanent techniques that are typically used include soldering and wire bonding to provide a connection from the IC device to a substrate with fan out wiring or a metal lead frame package. The temporary attachment techniques include rigid and flexible probes that are used to connect the IC device to a substrate with fan out wiring or directly to the test equipment.
The permanent attachment techniques used for testing integrated circuit devices such as wire bonding to a leadframe of a plastic leaded chip carrier are typically used for devices that have low number of interconnections and the plastic leaded chip carrier package is relatively inexpensive. The device is tested through the wire bonds and leads of the plastic leaded chip carrier and plugged into a test socket. If the integrated circuit device is defective, the device and the plastic leaded chip carrier are discarded.
The semi-permanent attachment techniques used for testing integrated circuit devices such as solder ball attachment to a ceramic or plastic pin grid array package are typically used for devices that have high number of interconnections and the pin grid array package is relatively expensive. The device is tested through the solder balls and the internal fan out wiring and pins of the pin grid array package that is plugged into a test socket. If the integrated circuit device is defective, the device can be removed from the pin grid array package by heating the solder balls to their melting point. The processing cost of heating and removing the chip is offset by the cost saving of reusing the pin grid array package.
The most cost effective techniques for testing and burn-in of integrated circuit devices provide a direct interconnection between the pads on the device to a probe sockets that is hard wired to the test equipment. Contemporary probes for testing integrated circuits are expensive to fabricate and are easily damaged. The individual probes are typically attached to a ring shaped printed circuit board and support cantilevered metal wires extending towards the center of the opening in the circuit board. Each probe wire must be aligned to a contact location on the integrated circuit device to be tested. The probe wires are generally fragile and easily deformed or damaged. This type of probe fixture is typically used for testing integrated circuit devices that have contacts along the perimeter of the device. This type of probe cannot be used for testing integrated circuit devices that have high density area array contacts. Use of this type of probe for high temperature testing is limited by the probe structure and material set.
High temperature wafer probing and burn-in testing has a number of technical challenges. Gold plated contacts are commonly used for testing and burn-in of IC devices. At high temperatures, the gold plated probes will interact with the solder balls on the IC device to form an intermetallic layer that has high electrical resistance and brittle mechanical properties. The extent of the intermetallic formation is dependent on the temperature and duration of the contact between the gold plated probe and the solder balls on the IC device. The gold-tin intermetallic contamination of the solder balls has a further effect of reducing the reliability of the flip chip interconnection to the IC device. Another problem caused by the high temperature test environment is diffusion of the base metal of the probe into the gold plating on the surface. The diffusion process is accelerated at high temperatures and causes a high resistive oxide layer to form on the surface of the probe contact.
OBJECT OF THE INVENTION
It is the object of the present invention to provide a probe for testing integrated circuit devices and other electronic components that use solder balls for the interconnection means.
Another object of the present invention is to provide a probe that is an integral part of the fan out wiring on the test substrate or other printed wiring means to minimize the contact resistance of the probe interface.
A further object of the present invention is to provide an enlarged probe tip to facilitate alignment of the probe array to the contact array on the IC device for wafer probing.
An additional object of the present invention is to provide a suitable contact metallurgy on the probe surface to inhibit oxidation, intermetallic formation, and out-diffusion of the contact interface at high temperatures.
Yet another object of the present invention is to provide a suitable polymer material for supporting the probe contacts that has a coefficient of thermal expansion that is matched to the substrate material and has a glass transition temperature greater than 200 C.
Yet a further object of the present invention is to provide a probe with a cup shaped geometry to contain the high temperature creep of the solder ball interconnection means on the integrated circuit devices during burn-in testing.
Yet an additional object of the present invention is to provide a probe with a cup shaped geometry to facilitate in aligning the solder balls on the integrated circuit device to the probe contact.
SUMMARY OF THE INVENTION
A broad aspect of the claimed invention is an apparatus for electrically testing a work piece having a plurality of electrically conductive contact locations thereon having: a substrate having a first surface and a second surface; a plurality of first electrical contact locations on the first side; a plurality of probe tips disposed on the first contact locations; each of the probe tips having an elongated electrically conductive member projecting from an enlarged base, the base being disposed on said contact locations; and, means for moving said substrate towards the work piece so that the plurality of probe tips are pressed into contact with the plurality of contact locations on said work piece.
Another broad aspect of the present invention is a method including the steps of: providing a substrate having a surface; bonding an elongated electrical conductor to the surface by forming a ball bond at the surface; shearing said elongated conductor from said ball bond leaving an exposed end of said elongated conductor, and flattening the exposed end.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other objects, features, and advantages of the present invention will become apparent upon further consideration of the following detailed description of the invention when read in conjunction with the drawing figures, in which:
FIG. 1 shows a cross section of a high density integral rigid test probe attached to a substrate and pressed against the solder balls on an integrated circuit device.
FIG. 2 shows an enlarged cross section of a single high density integral rigid test probe attached to the fan out wiring on the test substrate.
FIGS. 3-7 show the processes used to fabricate the high density integral rigid test probe structure on a fan out wiring substrate.
FIG. 8 shows an alternate embodiment of the high density integral rigid test probe structure with a cup shaped geometry surrounding the probe contact.
FIG. 9 shows an alternate embodiment of the high density integral rigid test probe with multiple probe arrays on a single substrate.
FIG. 10 shows the structure of FIG. 1 with contact locations on a second surface.
FIG. 11 shows the structure of FIG. 6 with conductive pins at the contact locations on the second surface.
FIG. 12 schematically shows the structure of FIG. 1 in combination with a means for moving the probe into engagement.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows a cross section of a test structure ( 10 ) and high density integral rigid test probe ( 12 ) according to the present invention. The test substrate ( 10 ) provides a rigid base for attachment of the probe structures ( 12 ) and fan out wiring from the high density array of probe contacts to a larger grid of pins or other interconnection means to the equipment used to electrically test the integrated circuit device. The fan out substrate can be made from various materials and constructions including single and multi-layer ceramic with thick or thin film wiring, silicon wafer with thin film wiring, or epoxy glass laminate construction with high density copper wiring. The integral rigid test process ( 12 ) are attached to the first surface ( 11 ) of the substrate ( 10 ). The probes are used to contact the solder balls ( 22 ) on the integrated circuit device ( 20 ). The solder balls ( 22 ) are attached to the first surface ( 21 ) of the integrated circuit device ( 20 ).
FIG. 2 shows an enlarged cross section of the high density integral rigid test probe ( 12 ). The probe tip is enlarged ( 13 ) to provide better alignment tolerance of the probe array to the array of solder balls ( 22 ) on the IC device ( 20 ). The integral rigid test probe ( 12 ) is attached directly to the fan out wiring ( 15 ) on the first surface ( 11 ) of the substrate ( 10 ) to minimize the resistance of the probe interface. The probe geometry includes the ball bond ( 16 ), the wire stud ( 17 ), and the enlarged probe tip ( 13 ). A sheet of polymer material ( 40 ) with holes ( 41 ) corresponding to the probe positions is used to support the enlarged tip ( 13 ) of the probe geometry. It is desirable to match the coefficient of thermal expansion for the polymer sheet ( 40 ) material and the substrate material to minimize stress on the interface between the ball bond ( 16 ) and the fan out wiring ( 15 ). As an example, the BPDA-PDA polyimide can be used with a silicon wafer substrate since both have a coefficient of thermal expansion (TCE) of 3 ppm/C. This material is also stable up to 350 C.
FIG. 3 shows the first process used to fabricate the integral rigid test probe. A thermosonic wire bonder tool is used to attach ball bonds ( 16 ) to the first surface ( 11 ) of the rigid substrate ( 10 ). The wire bonder tool uses a first ceramic capillary ( 30 ) to press the ball shaped end of the bond wire against the first surface ( 11 ) of the substrate ( 10 ). Compression force and ultrasonic energy ( 31 ) are applied through the first capillary ( 30 ) tip and thermal energy is applied from the wire bonder stage through the substrate ( 10 ) to bond the ball shaped end of the bond wire to the first surface ( 11 ) of the substrate. The bond wire is cut, sheared, or broken to leave a small stud ( 17 ) protruding vertically from the ball bond ( 16 ).
A first sheet of polymer material ( 40 ) with holes ( 41 ) corresponding to the probe locations on the substrate is placed over the array of wire studs ( 17 ) as shown in FIG. 4 . The diameter of the holes ( 41 ) in the polymer sheet ( 40 ) is slightly larger than the diameter of the wire studs ( 17 ). A second sheet of metal or a hard polymer ( 42 ) with holes ( 43 ) corresponding to the probe locations is also placed over the array of wire studs ( 17 ). The diameter of the holes ( 43 ) in the metal sheet ( 42 ) is larger than the diameter of the holes ( 41 ) in the polymer sheet ( 40 ).
The enlarged ends of the probe tips are formed using a hardened anvil tool ( 50 ) as shown in FIG. 5 . Compression force and ultrasonic energy ( 51 ) are applied through the anvil tool ( 50 ) to deform the ends of the wire studs ( 17 ). The size of the enlarged probe tip ( 13 ) is controlled by the length of the wire stud ( 17 ) protruding through the polymer sheet ( 40 ), the thickness of the metal sheet ( 42 ), and the diameter of the holes ( 43 ) in the metal sheet ( 42 ). The enlarged ends of the probes ( 13 ) can be formed individually or in multiples depending on the size of the anvil tool ( 50 ) that is used. Also, the surface finish of the anvil tool ( 50 ) can be modified to produce a smooth or textured finish on the enlarged probe tips ( 13 ). FIG. 6 shows the high density integral rigid test probe with the metal mask ( 42 ) removed from the assembly.
FIG. 7 shows the sputtering or evaporation process used to deposit the desired contact metallurgy ( 18 ) on the enlarged end ( 13 ) of the probe tip. Contact metallurgies ( 18 ) such as Pt, Ir, Rh, Ru, and Pd can be deposited in the thickness range of 1000 to 5000 angstroms over the probe tip ( 13 ) to ensure low contact resistance with thermal stability and oxidation resistance when operated a elevated temperatures in air. A thin layer of TiN, Cr, Ti, Ni, or Co can be used as a diffusion barrier ( 19 ) between the enlarged probe tip ( 13 ) and the contact metallurgy ( 18 ) on the surface of the probe.
FIG. 8 shows a high density integral test probe ( 12 ) with an additional sheet of polyimide ( 44 ) with enlarged holes ( 45 ) corresponding to the probe location placed on top of the first sheet of polyimide ( 40 ). The enlarged holes ( 45 ) in the second sheet of polyimide ( 44 ) acts as a cup to control and contain the creep of the solder balls at high temperatures.
Multiple probe arrays can be fabricated on a single substrate ( 60 ) as shown in FIG. 9 . Each array of probes is decoupled from the adjacent arrays by using separate polyimide sheets ( 61 , 62 ). Matched coefficients of thermal expansion for the polymer sheets ( 61 , 62 ) and the substrate ( 60 ) become increasingly more important for multiple arrays of probes on a large substrate. Each slight differences in the coefficient of thermal expansion can result in bowing of the substrate or excessive stresses in the substrate and polymer material over a large area substrate.
FIG. 10 shows the structure of FIG. 1 with second contact locations ( 70 ) on surface ( 72 ) of substrate 10 . Contact locations ( 70 ) can be the same as contact locations ( 13 ).
FIG. 11 shows the structure of FIG. 6 with elongated conductors ( 74 ) such as pins fixed to the surface ( 76 ) of pad ( 70 ).
FIG. 12 shows substrate ( 10 ) disposed spaced apart from the IC device ( 20 ). Substrate ( 11 ) is held by arm ( 78 ) of fixture ( 80 ). The IC device ( 20 ) is disposed on support ( 82 ) which is disposed in contact with fixture ( 80 ) by base ( 84 ). Arm ( 78 ) is adapted for movement as indicated by arrow ( 86 ) towards base ( 84 ) so that probe tips ( 12 ) are brought into engagement with conductors ( 22 ). An example of an apparatus providing a means for moving substrate ( 10 ) into engagement with the IC device ( 20 ) can be found in U.S. Pat. No. 4,875,614.
While we have described out preferred embodiments of our invention, 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 disclosed. | A high density integrated test probe and method of fabrication is described. A group of wires are ball bonded to contact locations on the surface of a fan out substrate. The wires are sheared off leaving a stub, the end of which is flattened by an anvil. Before flattening a sheet of material having a group of holes is arranged for alignment with the group of stubs is disposed over the stubs. The sheet of material supports the enlarged tip. The substrate with stubs form a probe which is moved into engagement with contact locations on a work piece such as a drip or packaging substrate. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is based upon and claims the benefit of priority from prior Japanese Patent Application No. P2002-051979, filed on Feb. 27, 2002; the entire contents of which are incorporated herein by reference.
FIELD OF THE INVENTION
The present invention relates to an optical sensing circuit, and more particularly, to a circuit suitable for producing a signal used for detecting a moving amount and a moving direction in a pointing device referred to as a so-called mouse in a computer.
BACKGROUND OF THE INVENTION
FIG. 1 shows a constitution of a conventional optical sensing circuit used for a pointing device. A circuit XCT 100 is provided for producing an X signal indicating a moving amount in an X direction and a moving direction, and a circuit YCT 100 is provided for producing a Y signal indicating a moving amount in a Y direction and a moving direction.
Between a power supply voltage VCC terminal and a ground voltage VSS terminal, a resistor RLED, a light emitting diode (LED) XLED for producing the X signal contained in the circuit XCT 100 , and a LED YLED for producing the Y signal contained in the circuit YCT 100 are connected in series in order to reduce the amount of current.
In the circuit XCT 100 , two signal producing paths are set up in parallel as a circuit of a photo receiving side. As a first path, a phototransistor X 1 PT and a resistor X 1 R are connected in series between the power supply voltage VCC terminal and the ground voltage VSS terminal, and a node X 1 between the phototransistor X 1 PT and the resistor X 1 R is connected to one input terminal of a comparator X 1 COMP.
As a second path, a phototransistor X 2 PT and a resistor X 2 R are connected in series between the power supply voltage VCC terminal and the ground voltage VSS terminal, and a node X 2 between the phototransistor X 2 PT and the resistor X 2 R is connected to one input terminal of a comparator X 2 COMP. Reference voltage Vref is applied to the other input terminal of each of the comparators X 1 COMP, X 2 COMP.
A rotary slit XSLT is arranged between the LED XLED and the phototransistors X 1 PT, X 2 PT. This rotary slit XSLT is rotated in accordance with movement of the pointing device in an X direction, and transmits light emitted from the LED XLED to the phototransistors X 1 PT, X 2 PT, or interrupts it. Here, in the phototransistors X 1 PT, X 2 PT, current flow is varied in accordance with the amount of received light, and voltage at the nodes X 1 , X 2 is accordingly varied. The phototransistor X 1 PT is oriented at predetermined angle relative to the phototransistor X 2 PT, and voltage waveforms at the nodes X 1 , X 2 have an about 90 degrees phase difference from each other.
Because of the foregoing constitution, the circuit XCT 100 operates as follows. When the pointing device moves in the X direction, the rotary slit XSLT is rotated in accordance with a moving amount and a moving direction thereof, and the amounts of light received at the phototransistors X 1 PT, X 2 PT are varied, and currents flowing in X 1 PT, X 2 PT are also varied. These variations of currents are converted into voltages by the resistors X 1 R, X 2 R, extracted as voltage signals from the nodes X 1 , X 2 , and applied to the comparators X 1 COM, X 2 COM, respectively.
In the comparator X 1 COMP, the voltage V (X 1 ) at the node X 1 is compared with the reference voltage Vref. A low level voltage is outputted when the voltage V (X 1 ) is below the reference voltage Vref, and a high level voltage is outputted when it is not less than the reference voltage Vref. Similarly, in the comparator X 2 COMP, the voltage V (X 2 ) at the node X 2 is compared with the reference voltage Vref. A low level voltage is outputted when the voltage V (X 2 ) is below the reference voltage Vref, and a high level voltage is outputted when it is not less than the reference voltage Vref. Thus, the rotation of the rotary slit XSLT, that is, how far the pointing device moves in the X direction, is detected with the pulse output from the comparator X 1 COMP. Additionally, because of the phase difference between the signals X 1 , X 2 as described above, a moving direction can also be detected.
The circuit YCT 100 also has a constitution for receiving light from the LED YLED similar to that of the circuit XCT 100 . Specifically, the circuit YCT 100 comprises the rotary slit YSLT, phototransistors Y 1 PT, Y 2 PT, resistors Y 1 R, Y 2 R, and comparators Y 1 COMP, Y 2 COMP, and operates similar to the circuit XCT 100 . Thus, explanation thereof will be omitted.
However, the following problems have been inherent in such a conventional optical sensing circuit.
FIG. 2A shows respective voltages V (X 1 ), V (X 2 ) at the nodes X 1 , X 2 . Further, FIG. 2B shows output waveforms of the comparators X 1 COMP, X 2 COMP when a threshold (=reference voltage Vref) of the comparators X 1 COMP, X 2 COMP is Vth 1 shown in FIG. 2A . FIG. 2C shows output waveforms of the comparators X 1 COMP, X 2 COMP when a threshold of the comparators X 1 COMP, X 2 COMP is Vth 2 shown in FIG. 2A .
To identify a rotational direction of the rotary slit XSLT, the threshold voltage Vth must be in a range between upper and lower points C 1 , C 2 at which the waveforms of the voltages V (X 1 ), V (X 2 ) at the nodes X 1 , X 2 intersect each other.
As the threshold Vth 1 ranges between the points C 1 , C 2 , for the outputs of the comparators X 1 COMP, X 2 COMP, there are an overlapping period 10 a of high levels and an overlapping period 10 b of low levels as shown in FIG. 2B . In such a case, it is possible to identify the rotational direction of the rotary slit XSLT. For example, in the period 10 b where both outputs are low, the output of the comparator X 1 COMP first rises to a high level, whereby the rotational direction can be detected.
However, if the threshold voltage Vth is at the intersection point C 1 as in the case of a threshold Vth 2 , or above the point C 1 , as shown in FIG. 2C , there is an overlapping period 12 b of low levels while there is no overlapping period 12 a of high levels. In such a case, it is impossible to identify the rotational direction of the rotary slit XSLT.
If output characteristics or light intensity of the LED is higher than those shown in FIG. 2A , or sensitivity of the phototransistor is higher, the voltages V (X 1 ), V (X 2 ) at the nodes X 1 , X 2 respectively become similar to those shown in FIG. 3A . FIG. 3B shows respective output waveforms of the comparators X 1 COMP, X 2 COMP when threshold of the comparators X 1 COMP, X 2 COMP is Vth 3 shown in FIG. 3A in this case. FIG. 3C shows respective output waveforms of the comparators X 1 COMP, X 2 COMP when threshold of the comparators X 1 COMP, X 2 COMP is Vth 4 shown in FIG. 3A .
As the threshold Vth 3 ranges between points C 3 , C 4 at which the waveforms of the voltages V (X 1 ), V (X 2 ) intersect each other, for outputs of the comparators X 1 COM, X 2 COMP, as shown in FIG. 2B , there are an overlapping period 20 a of high levels and an overlapping period 20 b of low levels. Thus, it is possible to identify the rotational direction of the rotary slit XSLT.
However, if the threshold voltage Vth is at the point C 4 of waveform intersection as in the case of a threshold Vth 4 , or below the point C 4 , as shown in FIG. 3C , there is an overlapping period 22 a of high levels, while there is no overlapping period 22 b of low levels. Also in such a case, it is impossible to identify the rotational direction of the rotary slit XSLT.
Normally, the LED or the phototransistor used for the pointing device greatly varies in light intensity or receiving sensitivity even under the same conditions. Accordingly, the respective elements are classified into several ranks and, in accordance with the rank, a value of the resistor RLED or values of the resistors X 1 R, X 2 R are adjusted for a normal operation.
However, there is still some variation even among the elements classified into the same rank. Therefore, the distance between the LED and the rotary slit or between the phototransistor and the rotary slit must be adjusted at the end.
Accordingly, if the light intensity emitted from the LED or the receiving sensitivity of the phototransistor is low as shown in FIG. 2A , or if the light intensity emitted from the LED or the receiving sensitivity of the phototransistor is high as shown in FIG. 3A , it may be difficult to set the threshold of the comparators within the range between the upper and lower points at which the waveforms of the output voltages V (X 1 ), V (X 2 ) of the phototransistors intersect each other.
Additionally, if the light intensity emitted from the LED or the receiving sensitivity of the phototransistor is high, as shown in FIG. 3A , the minimum voltage level of the waveforms of the voltages V (X 1 ), V (X 2 ) are considerably higher than the ground voltage VSS. For this reason, the case in which the light emitted from the LED is not interrupted by the rotary slit completely and thus received by the phototransistor, or light reflected on a portion other than the rotary slit is received by the phototransistor, or the like may often occur. If measures taken to counter such a phenomenon depend on mechanical structures or arrangements of the LED, the rotary slit and the phototransistors, the cost of the pointing device itself may be increased.
BRIEF SUMMARY OF THE INVENTION
An optical sensing circuit according to an embodiment of the present invention comprising:
a voltage to current conversion circuit to be connected between a output terminal of a light detector, which terminal output a voltage in accordance with the amount of detected light from a light source, and a second power supply terminal, configured to lower the voltage at the output terminal at by increasing a value of current flowing from the output terminal to the second power supply terminal as the voltage at the output terminal is lowered, and
a comparator circuit configured to compare the voltage at the output terminal with a reference voltage, and to output a signal in accordance with a result of the comparison.
A pointing device according to an embodiment of the present invention comprising:
a first optical sensing circuit configured to produce a signal indicating a moving amount and a moving distance in a first direction, and
a second optical sensing circuit configured to produce a signal indicating a moving amount and a moving distance in a second direction different from the first direction,
each of the first and second optical sensing circuits, comprises
a light source;
a first light detector connected between a first power supply terminal and a second power supply terminal, configured to output a first voltage to a first output terminal in accordance with the amount of detected light from the light source;
a second light detector configured to output a second voltage to a second output terminal in accordance with the amount of detected light from the light source, the second voltage having a relative 90 degrees phase difference from the first voltage;
a rotary slit arranged between the light source and the first and second light detector, configured to rotate in accordance with a movement of the pointing device in the first direction or the second direction and to pass or interrupt the light from the light source to the first and second light detectors;
a first voltage to current conversion circuit configured to lower the voltage at the first output terminal by increasing a value of current flowing from the first output terminal as the voltage at the first output terminal is lowered;
a second voltage to current conversion circuit configured to lower the voltage at the second output terminal by increasing a value of current flowing from the second output terminal as the voltage at the second output terminal is lowered;
a first comparator circuit configured to compare the voltage at the first output terminal with a reference voltage, and to output a first signal in accordance with a result of the comparison; and
a second comparator circuit configured to compare the voltage at the second output terminal with the reference voltage, and to output a second signal in accordance with a result of the comparison.
An optical sensing circuit according to an embodiment of the present invention comprising:
a voltage to current conversion circuit to be connected to an output of a light detector and configured to increase a value of current flowing through the circuit as a voltage of the output decreases; and
a comparator configured to compare the voltage of the output with a reference voltage.
BRIEF DESCRIPTION OF THE DRAWINGS
A more complete appreciation of embodiments of the present invention and many of its attendant advantages will be readily obtained by reference to the following detailed description considered in connection with the accompanying drawings, in which:
FIG. 1 is a circuit diagram showing a constitution of a conventional optical sensing circuit.
FIG. 2A is a graph showing voltage waveforms at output nodes X 1 , X 2 of phototransistors and thresholds of comparators in the optical sensing circuit shown in FIG. 1 .
FIG. 2B is a graph showing output waveforms of the comparators X 1 COMP, X 2 COMP when the threshold voltage is Vth 1 shown in FIG. 2A .
FIG. 2C is a graph showing output waveforms of the comparators X 1 COMP, X 2 COMP when the threshold voltage is Vth 2 shown in FIG. 2A .
FIG. 3A is a graph showing voltage waveforms at the output nodes X 1 , X 2 of the phototransistors and thresholds of the comparators X 1 COMP, X 2 COMP when light intensity of an LED or reception sensitivity of the phototransistor is high in the optical sensing circuit shown in FIG. 1 .
FIG. 3B is a graph showing output waveforms of the comparators X 1 COMP, X 2 COMP when the threshold voltage is Vth 3 shown in FIG. 3A .
FIG. 3C is a graph showing output waveforms of the comparators X 1 COMP, X 2 COMP when the threshold voltage is Vth 4 shown in FIG. 3A .
FIG. 4 is a circuit diagram showing a constitution of an optical sensing circuit according to a first embodiment of the present invention.
FIG. 5 is a graph showing voltage-current characteristics in an output terminal of a photodetector in the first embodiment.
FIG. 6 is a circuit diagram showing a constitution of an optical sensing circuit according to a second embodiment of the present invention.
FIG. 7 is a circuit diagram showing an example of circuitry of a variable current source in the second embodiment.
FIG. 8A is a graph showing voltage waveforms at output nodes X 1 , X 2 of phototransistors and thresholds of comparators in the second embodiment.
FIG. 8B is a graph showing output waveforms of the comparators X 1 COMP, X 2 COMP when the threshold voltage is Vth 1 shown in FIG. 8A .
FIG. 8C is a graph showing output waveforms of the comparators X 1 COMP, X 2 COMP when the threshold voltage is Vth 2 shown in FIG. 8A .
FIG. 9A is a graph showing voltage waveforms at the output nodes of X 1 , X 2 of the phototransistors and a threshold of the comparators when light intensity of an LED or receiving sensitivity of the phototransistor is high in the second embodiment.
FIG. 9B is a graph showing output waveforms of the comparators X 1 COMP, X 2 COMP when the threshold voltage is Vth 1 shown in FIG. 9A .
FIG. 9C is a graph showing output waveforms of the comparators X 1 COMP, X 2 COMP when the threshold voltage is Vth 2 shown in FIG. 9A .
FIG. 10 is a circuit diagram showing another example of circuitry of a variable current source in the second embodiment.
FIG. 11 is a circuit diagram showing a constitution of an optical sensing circuit according to a third embodiment of the present invention.
FIG. 12 is a circuit diagram showing a constitution of an optical sensing circuit according to a fourth embodiment of the present invention.
FIG. 13 is a graph showing voltage-current characteristics in an output terminal of a photodetector in the fourth embodiment.
DETAILED DESCRIPTION OF THE EMBODIMENTS
(1) First Embodiment
FIG. 4 shows a constitution of an optical sensing circuit according to a first embodiment of the present invention. This circuit comprises a circuit XCT 1 for detecting a moving amount in the X direction of a pointing device and its direction, and a circuit YCT 1 for detecting a moving amount in the Y direction and its direction. The circuit XCT 1 has an X light emitting portion 100 a , X photodetectors 101 a , 101 b , variable current sources 102 a , 102 b , and comparators 103 a , 103 b . The circuit YCT 1 has a Y light emitting portion 100 b , Y photodetectors 104 a , 104 b , variable current sources 105 a , 105 b , and comparators 106 a , 106 b.
The X light emitting portion 100 a and the Y light emitting portion 100 b are connected in series between a power supply voltage VCC terminal and a ground voltage VSS terminal to emit light.
In the circuit XCT 1 , the light emitted from the X light emitting portion 100 a is received by the X photodetectors 101 a and 101 b through a rotary slit XSLT rotated in accordance with a moving amount in the X direction and a moving direction of the pointing device.
In the circuit YCT 1 , the light emitted from the Y light emitting portion 100 b is received by the Y photodetectors 104 a and 104 b through a rotary slit YSLT rotated in accordance with a moving amount in the Y direction and a moving direction of the pointing device. In the circuit YCT 1 , optical sensing circuitry and its operation are basically similar to those of the circuit XCT 1 . Hereinafter, therefore, only the circuit XCT 1 will be described, while description of the circuit YCT 1 will be omitted.
In the circuit XCT 1 , in accordance with the amount of light received by the X photodetectors 101 a , 101 b , voltages V (X 1 ), V (X 2 ) at nodes X 1 , X 2 connected to respective output terminals thereof are varied. The comparator 103 a compares a predetermined threshold with the voltage V (X 1 ) at the node X 1 , and outputs a low level voltage when the voltage V (X 1 ) at the node X 1 is below the threshold, and a high level voltage when it is not less than the threshold. Similarly, the comparator 103 b compares the voltage V (X 2 ) at the node X 2 with a predetermined threshold, and outputs a low level voltage when the voltage V (X 2 ) at the node X 2 is below the threshold, and a high level when it is not less than the threshold.
In this case, the variable current sources 102 a , 102 b are respectively connected between the nodes X 1 , X 2 and the ground voltage VSS terminal. The variable current source 102 a increases current flowing from the node X 1 to the ground voltage VSS terminal as the voltage V (X 1 ) at the node X 1 is lowered, and accordingly operates to accelerate the pace of lowering the voltage V (X 1 ) at the node X 1 . Similarly, the variable current source 102 b increases current flowing from the node X 2 to the ground voltage VSS terminal as the voltage V (X 2 ) at the node X 2 is lowered, and accordingly operates to accelerate the pace of lowering the voltage V (X 2 ) at the node X 2 .
Since the variable current sources 102 a , 102 b having such negative resistance characteristics are added to the nodes X 1 , X 2 , as shown in FIG. 5 , as the voltages V (X 1 ), V (X 2 ) at the nodes X 1 , X 2 are lowered, the currents I (X 1 ), I (X 2 ) flowing from the node X 1 to the ground voltage VSS terminal and from the node X 2 to the ground voltage VSS terminal, respectively, are increased. Therefore, the voltages at the nodes X 1 , X 2 are lowered at accelerating paces.
As a result, since voltage waveforms at the nodes X 1 , X 2 are lowered to the level of the ground voltage VSS, even if there is variance in light emitting characteristics at the X light emitting portion 100 a , or in receiving characteristics of the X photodetectors 101 a , 101 b , a voltage range within which threshold voltage Vth should be set so as to identify a rotational direction is widened, and the threshold voltage Vth is always raised within the voltage range. Thus, stable outputs can be output from the comparators 103 a , 103 b , whereby a moving amount in the X direction and a moving direction can be surely detected.
In the aforementioned first embodiment, preferably, light intensity of the LEDs XLED, YLED is set high, and/or receiving sensitivity of the phototransistors X 1 PT, X 2 PT, Y 1 PT, Y 2 PT is set high.
(2) Second Embodiment
A second embodiment of the present invention corresponds to the first embodiment but realized by a more specific circuit.
FIG. 6 shows a constitution of an optical sensing circuit of the second embodiment. Correspondence to the first embodiment is as follows. That is, the circuit XCT 1 for detecting the X-direction movement corresponds to a circuit XCT 2 , the rotary slit XSLT to a rotary slit XSLT, the X light emitting portion 100 a to an LED XLED, the X photodetector 101 a to a phototransistor X 1 PT and a resistor X 1 R, the X photodetector 101 b to a phototransistor X 2 PT and a resistor X 2 R, the comparator 103 a to a comparator X 1 COMP, the comparator 103 b to a comparator X 2 COMP, the variable current source 102 a to a voltage detection circuit VDC 1 and a voltage to current conversion circuit V/C·CONV 1 , the variable current source 102 b to a voltage detection circuit VDC 2 and a voltage to current conversion circuit V/C·CONV 2 .
Additionally, the circuit YCT 1 for detecting the Y-direction movement corresponds to a circuit YCT 2 , the rotary slit YSLT to a rotary slit YSLT, the Y light emitting portion 100 b to an LED YLED, the Y photodetector 104 a to a phototransistor Y 1 PT and a resistor Y 1 R, the Y photodetector 104 b to a phototransistor Y 2 PT and a resistor Y 2 R, the comparator 106 a to a comparator Y 1 COMP, the comparator 106 b to a comparator Y 2 COMP, the variable current source 105 a to a voltage detection circuit VDC 3 and a voltage to current conversion circuit V/C·CONV 3 , and the variable current source 105 b to a voltage detection circuit VDC 4 and a voltage to current conversion circuit V/C·CONV 4 .
This second embodiment corresponds to the circuit shown in FIG. 1 , where the voltage detection circuit VDC 1 and the voltage to current conversion circuit V/C·CONV 1 are connected to the node X 1 , the voltage detection circuit VDC 2 and the voltage to current conversion circuit V/C·CONV 2 to the node X 2 , the voltage detection circuit VDC 3 and the voltage to current conversion circuit V/C·CONV 3 to the node Y 1 , and the voltage detection circuit VDC 4 and the voltage to current conversion circuit V/C·CONV 4 to the node Y 2 . Components identical to those shown in FIG. 1 are denoted by similar reference numerals, and explanation thereof will be omitted.
As described above, light emitted from the LED XLED is received through the rotary slit XSLT by the phototransistors X 1 PT, X 2 PT, and voltages V (X 1 ), V (X 2 ) at the nodes X 1 , X 2 are varied in accordance with the amount of received light thereof.
The voltage detection circuit VDC 1 detects the voltage V (X 1 ) at the node X 1 , and outputs a detected voltage signal to the voltage to current conversion circuit V/C·CONV 1 . The voltage to current conversion circuit V/C·CONV 1 converts the voltage signal into a current signal, and draws current in accordance with the voltage V (X 1 ) at the node X 1 from the node X 1 to a ground voltage VSS terminal. A current value at this time is set to be larger as the voltage V (X 1 ) at the node X 1 is lower. Similarly, the voltage detection circuit VDC 2 detects the voltage V (X 2 ) at the node X 2 , and outputs a detected voltage signal to the voltage to current conversion circuit V/C·CONV 2 . The voltage to current conversion circuit V/C·CONV 2 converts the voltage signal into a current signal, and draws current in accordance with the voltage V (X 2 ) at the node X 2 from the node X 2 to a ground voltage VSS terminal. A current value at this time is set to be larger as the voltage V (X 2 ) at the node X 2 is lower.
Thus, as described above with reference to the first embodiment, since values of currents flowing from the node X 1 to the ground voltage VSS terminal and from the node X 2 to the ground voltage VSS terminal are increased as the voltages V (X 1 ), V (X 2 ) at the nodes X 1 , X 2 are lowered, the voltages V (X 1 ), V (X 2 ) at the nodes X 1 , X 2 are lowered at accelerating paces.
Additionally, though explanation is omitted, for voltages V (Y 1 ), V (Y 2 ) at the nodes Y 1 , Y 2 , similarly, values of currents flowing from the node Y 1 to a ground voltage VSS terminal and from the node Y 2 to the ground voltage VSS terminal are increased as the voltages V (Y 1 ), V (Y 2 ) at the nodes Y 1 , Y 2 are lowered. Thus, the voltages V (Y 1 ), V (Y 2 ) at the nodes Y 1 , Y 2 are lowered at accelerating paces.
As in the case of the first embodiment, in the second embodiment, preferably, light intensity of the LEDs XLED, YLED is set high, and/or receiving sensitivity of the phototransistors X 1 PT, X 2 PT, Y 1 PT, Y 2 PT is set high.
FIG. 7 shows a constitution of the voltage detection circuit VDC 1 and the voltage to current conversion circuit V/C·CONV 1 , and similarly specific circuitry of the voltage detection circuit VDC 2 and the voltage to current conversion circuit V/C·CONV 2 in the circuit XCT 2 . Constitution of the voltage detection circuit VDC 3 and the voltage to current conversion circuit V/C·CONV 3 , similarly specified circuitry of the voltage detection circuit VDC 4 and the voltage to current conversion circuit V/C·CONV 4 in the circuit YCT 2 , and the specific circuit operations thereof are similar to those of the circuit XCT 2 , and this explanation will be omitted.
In order to supply power supply voltage VCC to a source of a P channel MOS transistor M 2 , a source and a drain of a P channel MOS transistor M 1 turned ON by grounding its gate are connected in series between the source of the transistor M 2 and a power supply voltage VCC terminal. A gate of the transistor M 2 is connected to the node X 1 or X 2 , and the voltage V (X 1 ) at the node X 1 or the voltage V (X 2 ) at the node X 2 is detected.
An input terminal of current mirror circuit constituted of N channel MOS transistors M 3 and M 4 is connected to a drain of the transistor M 2 , and its output terminal is connected to the node X 1 or X 2 . More specifically, a gate and a drain of the transistor M 3 are connected to the drain of the transistor M 2 , and its source is grounded. A drain of the transistor M 4 is connected to the node X 1 or X 2 , its gate is connected to a gate and a drain of the transistor M 3 , and its source is grounded.
Accordingly, the transistor M 2 detects the voltage at the node X 1 or X 2 . Current I 1 in accordance with this voltage flows through the transistors M 1 , M 2 and M 3 to the ground voltage VSS terminal, and current I 2 in accordance with this current I 1 further flows from the node X 1 or X 2 through the transistor M 4 to the ground voltage VSS terminal. In this case, a ratio of current I 1 to I 2 is determined based on a size ratio of the transistors M 3 to M 4 , which is a ratio of the current mirror circuit.
If the voltage V (X 1 ) or V (X 2 ) at the node X 1 or X 2 is high, the transistor M 2 approaches to an OFF state, and the current I 1 flowing from the power supply VCC terminal through the transistors M 1 , M 2 , and M 3 to the ground voltage VSS terminal becomes extremely small. In this case, since the current I 2 flowing from the node X 1 or X 2 through the transistor M 4 to the ground voltage VSS terminal also becomes small, the function for lowering the voltage V (X 1 ) or V (X 2 ) at the node X 1 or X 2 is hardly performed.
As the voltage V (X 1 ) or V (X 2 ) at the node X 1 or X 2 is lowered, the transistor M 2 gradually approaches to the ON state, and the current I 1 flowing from the power supply voltage VCC terminal through the transistors M 1 , M 2 , and M 3 to the ground voltage VSS terminal is increased. Accordingly, since the current I 2 flowing from the node X 1 or X 2 through the transistor M 4 to the ground voltage VSS terminal is similarly increased, a negative resistor function is performed to lower the voltage V (X 1 ) or V (X 2 ) at the node X 1 or X 2 at an accelerating pace.
As described above, by setting the light intensity of the LED XLED high and/or setting the receiving sensitivity of the phototransistors X 1 PT, X 2 PT high, while almost no light is received because of the interruption of the light by the rotary slit XSLT, the voltage V (X 1 ) or V (X 2 ) at the node X 1 or X 2 floats at a level greater than the ground voltage VSS in the circuit shown in FIG. 1 . However, according to the embodiment, due to the current flowing from the node X 1 or X 2 to the ground voltage VSS terminal, the voltage V (X 1 ) or V (X 2 ) at the node X 1 or X 2 is lowered almost close to the ground voltage VSS.
Therefore, in voltage waveforms at the nodes X 1 , X 2 , the voltage range between the upper and lower points of intersection of both voltage waveforms can be wider than that in the case of the circuit shown in FIG. 1 .
FIG. 8A shows voltage waveforms V (X 1 ), V (X 2 ) at the nodes X 1 , X 2 of the second embodiment. Further, FIG. 8B shows output waveforms of the respective comparators X 1 COMP, X 2 COMP when a threshold (=reference voltage Vref) of the comparators X 1 COMP, X 2 COMP is Vth 1 shown in FIG. 8A , and FIG. 8C shows output waveforms of the respective comparators X 1 COMP, X 2 COMP when a threshold of the comparators X 1 COMP, X 2 COMP is Vth 2 shown in FIG. 8A .
As described above, in order to identify a rotational direction of the rotary slit XSLT, threshold voltage Vth must be ranged between the upper and lower points C 11 , C 12 at which the voltage waveforms V (X 1 ), V (X 2 ) at the nodes X 1 , X 2 intersect each other.
Since the threshold Vth 1 ranges between the points C 11 , C 12 , for outputs of the comparators X 1 COMP, X 2 COMP, there are an overlapping period ha of high levels and an overlapping period 11 b of low levels as shown in FIG. 8B . Thus, it is possible to identify the rotational direction of the rotary slit XSLT.
Further, also in the case of the threshold Vth 2 , since Vth 2 ranges between the points C 11 and C 12 at which the voltage waveforms intersect each other, for outputs of the comparators X 1 COMP, X 2 COMP, there are an overlapping period 13 a of high levels and an overlapping period 13 b of low levels as shown in FIG. 8C , whereby the rotational direction of the rotary slit XSLT can be identified.
If the light intensity of the LED is much higher than that shown in FIG. 8A , and/or if the sensitivity of the phototransistor is high, the voltage waveforms V (X 1 ), V (X 2 ) at the nodes X 1 , X 2 are similar to those shown in FIG. 9A . FIG. 9B shows output waveforms of the comparators X 1 COMP, X 2 COMP when a threshold of the comparators X 1 COMP, X 2 COMP is Vth 3 shown in FIG. 9A , and FIG. 9C shows output waveforms of the comparators X 1 COMP, X 2 COMP when a threshold of the comparators X 1 COMP, X 2 COMP is Vth 4 shown in FIG. 9A .
Since the threshold Vth 3 ranges between points C 13 and C 14 at which the voltage waveforms intersect each other, for outputs of the comparators X 1 COMP, X 2 COMP, there are an overlapping period 21 a of high levels and an overlapping period 21 b of low levels as shown in FIG. 9B . Accordingly, it is possible to identify a rotational direction of the rotary slit XSLT.
Similarly, since the threshold Vth 4 ranges between the points C 13 and C 14 at which the voltage waveforms intersect each other, for outputs of the comparators X 1 COMP, X 2 COMP, there are an overlapping period 23 a of high levels and an overlapping period 23 b of low levels as shown in FIG. 9C , whereby the rotational direction of the rotary slit XSLT can be identified.
Therefore, even if there is a large variance in characteristics between the LED and the phototransistor, a voltage range within which the threshold voltage Vth should be set so as to identify the rotational direction is widened, and the threshold voltage Vth ranges within this voltage range. Thus, it is possible to obtain stable photodetection without increasing accuracy of mechanical arrangement or the like such as a distance between the LED and the rotary slit or between the phototransistor and the rotary slit, contributing to a cost reduction.
In this case, by setting a size of the transistor M 1 relatively smaller regarding a size ratio of the transistor M 1 to the transistor M 2 , the transistor M 1 operates as a resistive element. Thus, as shown in FIG. 10 , in place of the transistor M 1 , a resistor R 1 may be connected in series between the power supply voltage VCC terminal and the source of the transistor M 2 . Also in this case, this operation is similar to that of the circuit shown in FIG. 7 .
(3) Third Embodiment
In the aforementioned second embodiment, as shown in FIG. 7 , the gate of the P channel MOS transistor M 1 is grounded, and transistor M 1 is always maintained ON. On the other hand, according to the third embodiment, as shown in FIG. 11 , a control signal CTL is input to a gate of a transistor M 1 . This control signal CTL is applied by, for example, a central processing unit of a not-shown computer. For example, a control signal which becomes a low level when a pointing device is in an operating state and a high level when it is in a suspended state is input to the gate of the transistor M 1 , and accordingly the transistor M 1 is turned OFF in the suspended state. Thus, the entire circuit is not operated, and wasteful current consumption can be prevented. Since the low-level control signal CTL is applied to turn ON the transistor M 1 when the pointing device is in the operating state, an operation is similar to that of the second embodiment.
(4) Fourth Embodiment
In the aforementioned second and third embodiments, current values flowing from the nodes X 1 , X 2 to the ground voltage VSS terminal are fixed in accordance with the voltages V (X 1 ), V (X 2 ) at the nodes X 1 , X 2 detected by the voltage detection circuits VDC 1 , VDC 2 . More specifically, a current mirror ratio is fixed, which is determined based on a size ratio of the transistors M 3 to M 4 in the current mirror circuit shown in FIG. 7 , 10 or 11 .
On the other hand, according to the fourth embodiment, a current mirror ratio can be selected in stages among a plurality of values. FIG. 12 shows a constitution of the fourth embodiment.
A source of a P channel MOS transistor M 11 is connected to a power supply voltage VCC terminal, a gate is grounded, and the transistor M 11 is maintained ON. A source of a P channel MOS transistor M 12 is connected to a drain of the transistor M 11 , and its gate is connected to a node X 1 or X 2 . Further, corresponding to later-described three current mirror circuits, sources of three P channel MOS transistors M 13 to M 15 are connected to a drain of the transistor M 12 , and gates thereof are connected to the node X 1 or X 2 .
The current mirror circuits are respectively constituted to include N channel MOS transistors M 21 and M 22 corresponding to the transistor M 13 , N channel MOS transistors M 23 , M 24 corresponding to a transistor M 14 , and N channel MOS transistors M 25 , M 26 corresponding to a transistor M 15 .
A gate and a drain of the transistor M 21 are connected to a drain of the transistor M 13 , and its source is grounded. A drain of the transistor M 22 is connected to the node X 1 or X 2 , its gate is connected to the drain and the gate of the transistor M 21 , and its source is grounded integrally with the source of the transistor M 21 .
A gate and a drain of the transistor M 23 are connected to a drain of the transistor M 14 , and its source is grounded. A drain of the transistor M 24 is connected to the node X 1 or X 2 , its gate is connected to the drain and the gate of the transistor M 23 , and its source is grounded integrally with the source of the transistor M 23 .
A gate and a drain of the transistor M 25 are connected to a drain of the transistor M 15 , and its source is grounded. A drain of the transistor M 26 is connected to the node X 1 or X 2 , its gate is connected to the drain and the gate of the transistor M 25 , and its source is grounded integrally with the source of the transistor M 25 .
Further, a switch SW 1 is connected between the gate and the drain of the transistor M 21 , the gate of the transistor M 22 and the ground voltage VSS terminal. Similarly, a switch SW 2 is connected between the gate and the drain of the transistor M 23 , the gate of the transistor M 24 and the ground voltage VSS terminal. Additionally, a switch SW 3 is connected between the gate and the drain of the transistor M 25 , the gate of the transistor M 26 and the ground voltage VSS terminal.
Thus, according to the fourth embodiment, there are a first current mirror circuit constituted of the transistors M 21 , M 22 for driving current in accordance with voltage at the node X 1 or X 2 detected by the transistors M 12 , M 13 , a second current mirror circuit constituted of the transistors M 23 and M 24 for driving current in accordance with voltage at the node X 1 or X 2 detected by the transistors M 12 , M 14 , and a third current mirror circuit constituted of the transistors M 25 and M 26 for driving current in accordance with voltage at the node X 1 or X 2 detected by the transistors M 12 , M 15 . Then, the circuit in which the corresponding switches SW 1 to SW 3 are OFF is operated, and the circuit in which the corresponding switches are ON is not operated. For example, only the first current mirror circuit is operated when the switches SW 2 and SW 3 are ON, and only the second current mirror circuit is operated when the switches SW 1 and SW 3 are ON. A size ratio of the transistors M 21 to M 22 in the first current mirror circuit, a size ratio of the transistors M 23 to M 24 in the second current mirror circuit, and a size ratio of the transistors M 25 to M 26 in the third current mirror circuit are set different from one another, e.g., 1:2:4. Accordingly, a desired current mirror ratio, and a desired one of the voltage-current characteristics in the output terminal of the phototransistor shown in FIG. 13 can be selected in accordance with characteristics of the LED or the phototransistor, characteristics changed depending on the shape of the rotary slit or arrangement of the respective components, or the like, and a stable photodetection output can be obtained. Incidentally, though explanation is omitted, the circuit of FIG. 12 can be applied not only to the circuit for detecting an X-direction movement but also to the circuit for detecting a Y-direction movement.
The foregoing embodiments are all examples, and not limited to the present invention. For example, the circuitry shown in each of FIGS. 6 , 7 , 10 to 12 is an example, and various modifications and variations can be made such as reversal of transistor polarity.
While there has been illustrated and described embodiments of the present invention, it will be understood by those skilled in the art that various change and modifications may be made, and equivalents may be substituted for devices thereof without departing from the true scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teaching of the present invention without departing from the central scope thereof. Therefore, it is intended that this invention not be limited to the particular embodiment disclosed, but that invention include all embodiments falling the scope of the appended claims. | An optical sensing circuit is provided with a light detector, a voltage to current conversion circuit connected to the light detector, and a comparator. The voltage to current conversion circuit includes an electric resistor and a current mirror circuit connected in parallel to the resistor. The voltage to current conversion circuit increases an electric current flowing through the circuit as a voltage of the output of the light detector decreases. The comparator compares the voltage of the output of the light detector with a reference voltage. | 6 |
This application is a division of application Ser. No. 137,243, filed Apr. 4, 1980, now U.S. Pat. No. 4,319,928, which is a continuation-in-part of application Ser. No. 105,102, filed Dec. 19, 1979, now abandoned.
BACKGROUND OF THE INVENTION
Much work has been done in the dairy industry relating to the production of aroma. Aroma production in milk was considered in 1933 by Michaelian, Farmer, and Hammer, The Relationship of Acetylmethylcarbinol and Diacetyl to Butter Cultures, Iowa Agr. Expt. Sta., Research Bull. 155. This article reports that citric acid-fermenting bacteria could produce large amounts of aroma compound diacetyl. In 1941, Hoecker and Hammer investigated the ability of Streptococcus diacetilactis to produce aroma in butter. Flavor Development in Salted Butter by Pure Cultures of Bacteria, Iowa Agr. Expt. Sta., Research Bull. 290 (1941).
By 1961 Lundstedt had developed a procedure for enhancing the flavor of cottage cheese and other dairy products through the use of Streptococcus diacetilactis. (U.S. Pat. No. 3,048,490). Moseley, Elliker and Sandine developed a variation on the Lundstedt process for making cottage cheese by 1964 (U.S. Pat. No. 3,323,921). In 1970, a still further variation of the process of making cottage cheese was developed by Sing (U.S. Pat. No. 3,968,256). This process involved the bulk addition of concentrated Streptococcus diacetilactis to cottage cheese without the need for further incubation. In all of these processes, one of the objects was to use Streptococcus diacetilactis because it produced diacetyl which enhanced the flavor.
It was also observed in the early 60's that the presence of Streptococcus diacetilactis had an inhibitory effect on spoilage organisms. In order to achieve the maximum inhibition of spoilage organisms, a relatively high concentration of Streptococcus diacetilactis in the finished cheese would be desired. However, if such a large concentration of Streptococcus diacetilactis were used, there was a tendency for excess production of the flavor compounds of diacetyl and acetaldehyde. Thus with the known processes of the prior art, one could obtain either an ideal maximum shelf life or an ideal flavor production, but not both. Efforts to overcome these problems lead to attempts to isolate strains of bacteria which had less flavor but which retained the full inhibitory effect.
In 1969, Burrow, Sandine, Elliker and Speckman pointed out the problem of too much flavor when maximum shelf life was obtained. Characterization of Diacetyl Negative Mutants of Streptococcus diacetilactis, Journal of Dairy Science, Vol. 53, p. 121-125. They noted that there was a need for strains of S. diacetilactis with impaired abilities to synthesize diacetyl. It was suggested in this 1969 article that since acetaldehyde appears to be a precursor of diacetyl during citrate metabolism, it was also believed that mutants of S. diacetilactis could be isolated with reduced aldehyde production. The authors reported that "Such strains would prove useful in manufacturing cultured products which often suffer from the green flavor defect." The authors reported that mutants of Streptococcus diacetilactis which they had developed produced an average of forty percent more lactic acid than parent strains; had acetaldehyde production which varied from quantities equal to the wild type to less than one-third the amount produced by the parents; and which retained inhibitory powers against food spoilage bacteria similar to their respective parents. However, the high acid and acetaldehyde production by the isolated mutants made their use in cottage cheese dressing impractical. The article suggested that this approach to extending the shelf life of cottage cheese and other foods seemed promising and reported that efforts were being continued to isolate new mutants which would produce less acid and aldehyde and still yield high cell numbers.
While efforts along this line had met with failure and research along this line had apparently ended, research concerning the biochemical pathways of Streptococcus lactis and Streptococcus diacetilactis has been taking place. In work of Kempler and McKay, studies of plasmid activity within Streptococcus diacetilactis led to the generation of various mutant forms of Streptococcus diacetilactis. Two articles about this work are entitled "Characterization of Plasmid Deoxyribonucleic Acid in Streptococcus lactis Subsp. diacetilactis: Evidence for Plasmid-Linked Citrate Utilization", Applied and Environmental Microbiology, Feb. 1979, pp. 316-323, Vol. 37, No. 2 and "Genetic Evidence for Plasmid-Linked Lactose Metabolism in Streptococcus lactis Subsp. diacetilactis", Applied and Environmental Microbiology, May, 1979, pp. 1041-1043, Vol. 37, No. 5. In studying the mechanism of the production of diacetyl from citrate as well as the lactose metabolism of Streptococcus diacetilactis, the authors Kempler and McKay treated S. diacetilactis strains 18-16 and DRCl with acridine orange to eliminate various ones of the plasmids which were within the bacteria. As early as 1972, McKay et al. showed that acriflavin treatment of S. diacetilactis 18-16 resulted in the appearance of lactose-negative derivatives, implying the involvement of plasmid DNA in lactose utilization. While innumerable mutants were developed during the 70's for the purpose of determining the biological mechanisms of the bacteria, there were no reports of Kemper and McKay over the retention or lack of retention of inhibitory powers against food spoilage bacteria. Indeed, most of the mutant bacteria only had value in the research setting since they often had commercially desirable metabolic pathways significantly damaged by the mutating procedure. Thus the typical mutant developed for purposes of understanding the metabolic pathways was not considered as a bacterium which had commercial application. Most mutants of this type would be totally unsuited for commercial use.
SUMMARY OF THE INVENTION
The invention relates to a blend of a first type of Streptococcus diacetilactis containing both a normal acetaldehyde- and diacetyl-producing strain and a second mutant type which retains its ability to inhibit food spoilage bacteria but does not have an appreciable amount of diacetyl or acetaldehyde production when grown in a milk substrate. The blend is added to achieve in the final cheese a cell count of at least one million cells per gram of the finished cheese. Through the use of the two types of S. diacetilactis, for the first time, a manufacturer of cottage cheese can optimize both the cell count to achieve the desired inhibition and the flavor production to achieve the desired flavor in the finished product.
Applicant has discovered that two of the mutant strains used by Kempler and McKay not only produce little or no acetaldehyde or diacetyl, but also do not produce other undesirable products such as excess acid. Yet these mutant strains retain their inhibitory properties against spoilage organisms. While these strains have the defect of essentially no flavor production, this defect can be overcome with proper proportioning with a normal strain. For the first time, cottage cheese can be made with the maximum possible shelf life obtainable from S. diacetilactis and yet have virtually any amount of flavor that may be desired, from very mild to strong.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In describing the invention, reference will be made to specific examples of the invention for purposes of illustration of the principles related to the invention and for purposes of disclosing the preferred method of practicing the invention in a manner which will enable a person of ordinary skill to practice the invention in its various forms.
In the preferred embodiment, a normal and a mutant strain are used. Reference to "normal strain" or "normal Streptococcus diacetilactis" as used herein is intended to include any strain of Streptococcus diacetilactis which will produce substantial amounts of diacetyl in a milk culture and which has the characteristic of inhibition of spoilage organisms which is typical of Streptococcus diacetilactis. Many of the normal strains of Streptococcus diacetilactis are known. The preferred strain is A.T.C.C. No. 15346 used by Sing in U.S. Pat. No. 3,968,256 and Moseley, Elliker and Sandine in U.S. Pat. No. 3,323,921.
Mutant strains which are suitable for use with the invention include strains 818 and 819, or their equivalent. These strains have been deposited in the Stock Culture Collection of the U.S. Department of Agriculture, Northern Regional Research Laboratory, Peoria, Ill. 61604, from which organization samples of these strains may be obtained. Strain 818 has been assigned the accession number of NRRL B-12070. Strain 819 has been assigned the accession number NRRL B-12071.
After selecting a normal and a mutant strain, the Streptococcus diacetilactis are separately grown in conventional fashion and thereafter the cells are separated from the growth media in the form of a paste as set forth in U.S. Pat. No. 3,968,256, which is incorporated herein by reference. From 5 to 95 parts of the cell paste normal strain are added to from 5 to 95 parts of the cell paste containing the mutant strain of 818 or 819 (or the equivalent). To this blend are added additional parts of a suitable carrier for maintenance of viability but not in sufficient amounts to dilute the total Streptococcus diacetilactis cell count to as low as 3×10 9 cells per gram.
The resultant bacteria-containing composition is then placed in small containers. These containers are sealed and cooled to below 0° C., typically below -20° C., more preferably below -30° C. With the preferred carrier, the contents become frozen at this low temperature.
While there is illustrated the preferred method of separately obtaining a paste for each of the two strains, it would be possible also to mix prior to obtaining the paste, either by growing the two strains together or by mixing the separate ripened cultures prior to separation of the cells. If the cells are grown to a sufficient concentration of cells above 3×10 9 cells per gram, the separation step can be eliminated. With this procedure, the suitable carrier could be incorporated as a part of the media.
When it is desired to make cottage cheese, a sealed container of the bacteria-containing composition is warmed to above 0° C. and preferably added to and mixed with a cottage cheese creaming mixture. The creaming mixture is then added to cottage cheese curds and blended in the conventional manner. The bacteria-containing composition is added in an amount to achieve at least 1.0×10 6 cells of Streptococcus diacetilactis per gram of cottage cheese.
EXAMPLE 1
Fifty liters of citrate-containing heat treated milk substate medium is cooled to about 30° C. and then inoculated with an active culture of Streptococcus diacetilactis A.T.C.C. No. 15346 in sufficient amount to provide a luxurious growth after about 12-16 hours. After the luxurious growth is obtained, the culture is then centrifuged to obtain a cell-containing paste which is separated from the supernatant. The harvested paste is diluted with a phosphate buffered diluent containing 2% monosodium glutamate to obtain an optimum pH of 6.6-6.8 for maintenance of viability and to standardize the preparation of this first strain to a known cell concentration of 1.5×10 11 cells per gram.
While the preparation of the first strain is progressing, 450 liters of heat treated milk substrate medium is cooled to about 30° C. and then inoculated with an active culture of Streptococcus diacetilactis strain 818 in sufficient amount to provide a luxurious growth after about 12-16 hours. After the luxurious growth is obtained, the culture is then centrifuged to obtain a cell-containing paste which is separated from the supernatant. The harvested paste is diluted with a phosphate buffered diluent containing 2% monosodium glutamate to obtain an optimum pH of 6.6-6.8 for maintenance of viability and to standardize the preparation of this second strain to a known concentration of 1.5×10 11 cells per gram.
Ninety parts of the standardized preparation of the second strain are added to and mixed with 10 parts of the standardized preparation of the first strain. This mixture is then placed in 60 gram, 240 gram and 400 gram containers which are sealed and cooled to -40° C., more preferably to -50° C., until the contents are frozen. These frozen containers are then shipped to dairy plants and stored at temperatures below -20° C., more preferably to -30° C. until needed.
At the dairy plants, cottage cheese curd is prepared in conventional fashion. Cottage cheese creaming mixture is also prepared in conventional fashion except that the frozen mixture is thawed, removed from its container and added to and mixed with the creaming mixture. The amount of frozen mixture used is sufficient to achieve a cell count of about 10 million cells per gram in the finished cottage cheese. (Roughly 30 grams of the mixture per 1000 lbs. of the cottage cheese). The creaming mixture is then blended with the curd in conventional fashion. The finished cottage cheese is kept cool to prevent significant growth of bacteria.
The cottage cheese produced has an excellent mild flavor and excellent shelf life.
A comparison is made to illustrate the advantages of this cottage cheese:
(1) Cottage cheese produced according to Example 1, with 10 parts of the first strain and 90 parts of the second strain.
(a) flavor: desirable mild diacetyl flavor progressing to moderate after 30 days.
(b) shelf life: about 40 days at 7.2° C.
(2) Cottage cheese produced having the same total cell count of Streptococcus diacetilactis as in Example 1 but only with the first strain of Streptococcus diacetilactis
(a) flavor: strong diacetyl flavor progressing to very strong after 30 days
(b) shelf life: about 40 days at 7.2° C.
(3) Cottage cheese produced having the same total cell count of Streptococcus diacetilactis but only with the second strain of Streptococcus diacetilactis
(a) flavor: no diacetyl flavor
(b) shelf life: about 40 days at 7.2° C.
(4) Cottage cheese produced having 10% of the total cell count of Streptococcus diacetilactis as in Example 1, but only with the first strain of Streptococcus diacetilactis
(a) flavor: desirable mold diacetyl flavor progressing to moderate after about 20 days
(b) shelf life: about 30 days at 7.2° C.
(5) Cottage cheese produced having 10% of the total cell count of Streptococcus diacetilactis as in Example 1, but only with the second strain of Streptococcus diacetilactis.
(a) flavor: no diacetyl flavor
(b) shelf life: about 30 days at 7.2° C.
(6) Cottage cheese produced without any Streptococcus diacetilactis.
(a) flavor: no diacetyl flavor
(b) shelf life: less than 20 days at 7.2° C.
EXAMPLE 2
The procedure of Example 1 is repeated except that a ratio of 50 parts of strain 1 and 50 parts of strain 2 is used. Similar results are achieved.
EXAMPLE 3
The procedure of Example 1 is repeated except that strain 819 is substituted for strain 818. Similar results are achieved.
EXAMPLE 4
The procedures of Examples 1 and 3 are repeated except that a ratio of 33 parts of strain 1 and 67 parts of strain 2 are used. Similar results are achieved. | A bacteria-containing composition for use in making cottage cheese is prepared containing a strain of Streptococcus diacetilactis that produces substantial amounts of diacetyl in a milk culture, a strain of diacetyl deficient mutant Streptococcus diacetilactis that produces essentially no diacetyl in a milk culture and a suitable carrier for maintaining viability of the Streptococcus diacetilactis. By the use of the two types of Streptococcus diacetilactis, a manufacturer of cottage cheese can optimize both the cell count to achieve the desired inhibition of spoilage bacteria and flavor production to achieve the desired flavor in the finished product. | 2 |
BACKGROUND
[0001] Liquid nitrogen (LN 2 ) is used for many applications in industry because of its thermal characteristics. In large systems, the LN 2 is usually sourced from a large reservoir located far away from the device that uses the LN 2 . One problem with this delivery method is that the LN 2 can begin to boil off in the delivery lines. Even with vacuum jacket lines, if the line is not used often, the LN 2 will begin to boil off in the line and turn to gas nitrogen (GN 2 ). Moreover, the last few feet of lines carrying the LN 2 into the device are typically plumbed with copper tube that is at room temperature. At room temperature LN 2 will boil off into GN 2 in a relatively rapid fashion.
[0002] Because of this boiling off of the LN 2 , when a device requests a flow of LN 2 all the GN 2 in the supply lines must first be vented off before the flow of LN 2 can be delivered. In systems that use LN 2 for process control, such as fluids carts or chambers, the delay caused by the required venting of the GN 2 can cause major temperature oscillations resulting in unacceptable performance. In addition, waiting for the LN 2 to arrive can add up to twenty minutes per cycle resulting in added cycle time and more cost.
[0003] For the reasons stated above and for other reasons stated below which will become apparent to those skilled in the art upon reading and understanding the present specification, there is a need in the art for a an efficient and effective system and method of removing or preventing GN 2 in an LN 2 delivery system.
SUMMARY OF INVENTION
[0004] The above-mentioned problems of current systems are addressed by embodiments of the present invention and will be understood by reading and studying the following specification.
[0005] In one embodiment, an LN 2 maintenance system is provided. The maintenance system includes an input sensor and a solenoid. The input sensor is adapted to monitor the temperature of the medium in an input tube to a device using the LN 2 . The solenoid is adapted bleed off the medium based on the monitored temperatures.
[0006] In another embodiment, a liquid nitrogen (LN 2 ) system is provided. The system comprises an input tube, an input sensor, and a solenoid. The input tube is used to provide a flow of LN 2 to a device. The input sensor is adapted to measure the temperature in the input tube. The solenoid is adapted to selectively bleed off a medium in the input tube during idle periods of the device based on the measured temperatures.
[0007] In yet another embodiment, a method of maintaining a supply of a medium in a first state is provided. The method includes measuring the temperature of the medium in an input tube. Comparing the measured temperature with a reference temperature and when the measured temperature is above the reference temperature, bleeding off the medium in the input tube.
[0008] In still another embodiment, a liquid nitrogen (LN2) maintenance system is provided. The system includes a means to automatically bleed off gas nitrogen (GN2) in an input tube during idle periods of a device using the LN 2 so that LN2 is available relatively instantaneously upon activation of the process control chamber.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] The present invention can be more easily understood and further advantages and uses thereof more readily apparent, when considered in view of the description of the preferred embodiments and the following figures in which:
[0010] FIG. 1 is an illustration of a LN 2 system of the present invention; and
[0011] FIG. 2 is a flow chart illustrating one method of an embodiment of the present invention.
[0012] In accordance with common practice, the various described features are not drawn to scale but are drawn to emphasize specific features relevant to the present invention. Reference characters denote like elements throughout Figures and text.
DETAILED DESCRIPTION
[0013] In the following detailed description, reference is made to the accompanying drawings, which form a part hereof, and in which is shown by way of illustration specific embodiments in which the inventions may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention, and it is to be understood that other embodiments may be utilized and that logical, mechanical and electrical changes may be made without departing from the spirit and scope of the present invention. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is defined only by the claims and equivalents thereof.
[0014] Embodiments of the present invention provide an efficient and effective method of providing LN 2 to system. In particular, in embodiments of the present invention, a small amount of LN 2 and/or GN 2 is automatically bled off during idle periods so that GN 2 does not have time to build up in an input tube. By doing this, LN 2 is available immediately when requested in the chamber.
[0015] Referring to FIG. 1 , an illustration of a LN 2 system 100 of one embodiment of the present invention is provided. As illustrated, FIG. 1 includes a chamber 104 for process control. An input tube 102 is used to plumb LN 2 into the chamber 104 . In one embodiment, the input tube is a copper tube having an input 112 to receive a flow of LN 2 from vacuum jacket lines (not shown) and an output 114 to output the flow of LN 2 to the chamber 104 . The LN 2 system includes a LN 2 maintenance system. The maintenance system includes a control input sensor 108 , a controller 106 and a solenoid 110 . The control input sensor 108 is in contact with input tube 102 . The control input sensor 108 measures the temperature of the medium (gas or liquid) in the input tube 102 . The control input sensor 108 is in communication with the controller 106 . The controller 106 is coupled to the solenoid 110 . The solenoid 110 selectively bleeds GN 2 from the input tube 102 under the control of the controller 106 when the system is idle. In particular, the controller 106 activates the solenoid 110 to bleed of the medium (LN 2 or GN 2 ) in the input tube 102 when the input sensor 108 senses a temperature that indicates a gas is in the input tube 102 . In one embodiment, the medium is bleed off through and exhaust tube 116 . In another embodiment, the medium is simply bled off into the chamber 104 . The heaters in the chamber 104 can easily overcome the effects of the medium during its hot dwell. This embodiment allows for fewer moving parts and allows the system to be retrofitted to existing systems. Moreover, in an embodiment in which the medium is bled off into the chamber, the medium can be used to cool the chamber off by bleeding off small amounts of the medium.
[0016] The LN 2 system described above in relation to a chamber 104 is made by way of example and not be limitation. Many different types of devices that use LN 2 can utilize embodiments of the LN 2 maintenance system of the present invention. Another example is a fluid chiller where the LN 2 conditions a fluid that is circulated in a closed loop.
[0017] Referring to FIG. 2 , a flow chart 200 illustrating one method of the present invention is provided. As illustrated in FIG. 2 , the process starts by monitoring the temperature of the medium in the input tube ( 202 ). In embodiments of the present invention this is done with an input sensor 108 that is coupled to measure the temperature of the medium in the input tube 102 . In one embodiment, the input sensor 108 is simply in thermal communication with a portion of the input tube 108 . In another embodiment, the input sensor 108 is in direct thermal contact with the medium in the input tube 108 .
[0018] Temperatures sensed by the input sensor 108 are compared by the controller 106 to a stored reference temperature ( 204 ). In embodiments of the present invention, the reference temperature is selected to ensure gas will not build up in the input tube 102 . In one embodiment, the reference temperature is the temperature in which a liquid changes to a gas. In another embodiment, the reference temperature is a temperature near the temperature in which the liquid changes to a gas. If a sensed temperature is below the reference temperature ( 204 ), the input sensor 108 continues to monitor the medium ( 202 ). If a sensed temperature is above the reference temperature ( 204 ), the solenoid 110 is activated to bleed off the medium ( 206 ). As illustrated in FIG. 2 , the process continues by monitoring the temperature of the medium ( 202 ).
[0019] When the system 100 is using the LN 2 for process control, the solenoid 110 will not bleed any LN 2 because the temperature of the medium (which will be LN 2 ) will be below the reference temperature. Hence, the present invention will only bled off small amounts of LN 2 during periods of idle time. Moreover, embodiments of the present invention control the temperature at the inlet to the system. When the supply line is completely full of GN 2 , the embodiments of the present invention will bleed the GN 2 at full power. Once the LN 2 arrives at the inlet (input tube 102 ), the embodiments will only bleed the LN 2 at a rate necessary to maintain it at the input tube 102 . Accordingly, embodiments of the present invention provide an efficient and effective bleeding system that is free from operator input. In addition in systems sourced by long LN 2 feed lines, the present invention is critical for performance.
[0020] Although specific embodiments have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that any arrangement, which is calculated to achieve the same purpose, may be substituted for the specific embodiment shown. This application is intended to cover any adaptations or variations of the present invention. For example, other systems requiring a medium of a first state could use the above embodiments. Therefore, it is manifestly intended that this invention be limited only by the claims and the equivalents thereof. | A LN 2 maintenance system is provided. The maintenance system includes an input sensor and a solenoid. The input sensor is adapted to monitor the temperature of the medium in an input tube to a device using the LN 2 . The solenoid is adapted bleed off the medium based on the monitored temperatures. | 5 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation-in-part of U.S. application Ser. No. 10/459,062, filed Jun. 11, 2003, now issued as U.S. Pat. No. 7,402,625, the disclosure of which is incorporated by reference in its entirety.
FIELD OF THE INVENTION
[0002] The present invention relates to compositions and a method for improving the melt processing of polymeric materials, and more particularly to the use of polymer processing aids combined with coupling agents to enhance the melt processing of polymeric materials that include fillers.
BACKGROUND OF THE INVENTION
[0003] Fluoropolymers are often utilized as processing aids in the melt processing of polymeric materials, such as polyolefins. The polymeric materials possess certain viscoelastic characteristics that, when melt processed, may result in undesirable defects in the finished material. This is particularly evident in extrusion processes for a given extrudable polymer where there exists a critical shear rate above which the surface of the extrudate exhibits melt defects. The melt defects may be present as a rough surface on the extrudate, commonly referred to as melt fracture. Melt fracture is primarily a function of the rheology of the polymer and the temperature and speed at which the polymer is processed. Melt fracture may take the form of “sharkskin”, a loss of surface gloss, that in more serious manifestations appears as ridges running more or less transverse to the extrusion direction. The extrudate may, in more severe cases, undergo “continuous melt fracture” where the surface becomes grossly distorted.
[0004] Fluoropolymers are capable of alleviating melt fracture in many polymeric materials. The fluoropolymers are incorporated into the polymeric materials in an amount generally of about 2% by weight or less.
[0005] Melt processable polymeric materials, hereinafter referred to as polymeric binders, are often combined with certain fillers or additives to both enhance the economics and to impart desired physical characteristics to the processed material. The fillers may include various organic material or inorganic material mixed throughout the polymeric host material. For example, wood flour or wood fibers are often included with certain hydrocarbon polymers to make a composite that is suitable as structural building material upon melt processing.
[0006] The incorporation of conventional fillers and additives may adversely affect the efficacy of the fluoropolymers incorporated into the melt processable mixture as a processing aid. Such fillers can interfere with the ability of the fluoropolymer to reduce melt fracture. Thus, melt fracture may occur at processing speeds that are undesirably low. Additionally, an increase of the amount of processing aid in the polymeric mixture does not reduce the melt fracture of the polymeric material to acceptable levels. For purposes of the present invention, the fillers and additives hereinafter will be referred to as interfering components.
SUMMARY OF THE INVENTION
[0007] The present invention is directed to addressing the problem created through the use of interfering components in melt processable polymeric binders and the interfering component's adverse affect on the performance of conventional polymer processing aids. The utilization of the present invention reduces the melt fracture generally experienced when melt processing polymeric binders with interfering components.
[0008] In one aspect of the invention, a composition having a controlled polymer architecture is employed as a coupling agent in combination with a polymer processing aid. The combination when applied with a polymeric binder and an interfering component is capable of significantly reducing melt fracture in melt processable admixtures. Additionally, improved physical properties such as tensile strength, flexural modulus, water uptake may also be realized.
[0009] Coupling agents may include block copolymers. Block copolymers generally include di-block copolymers, tri-block copolymers, random block copolymers, graft-block copolymers, star-branched block copolymers or hyper-branched block copolymers. Preferably, the block copolymers are amphiphilic block copolymers.
[0010] Polymer processing aids are those fluoropolymers generally recognized in the melt processing field as being capable of improving melt processability of polymers. The fluoropolymers may be thermoplastic or elastomeric materials. Preferred fluoropolymers include homopolymers or copolymers derived from vinylidene difluoride, hexafluoropropylene, and tetrafluoroethylene monomers. Additionally, other conventional additives may be included with the fluoropolymer to impart specific functional features.
[0011] Polymer processing aids improve the processing efficiency of polymeric products including film, sheet, pipe, wire and cable. The additive polymer processing aids at low levels into a formulation may improve surface quality of the product by eliminating surface defects like melt fracture, prevent the occurrence of internal or external die build up, and reduce or eliminate the formation of processing induced gels particles. The present invention may also lower the pressure in the melt and the apparent viscosity of the polymer melt and thus positively impact overall extrudate throughput or allow lower processing temperatures to be utilized. Lower processing temperatures may have a beneficial impact on extrudate color.
[0012] Conventionally recognized polymeric binders and interfering components may be utilized to form the polymeric mixture suitable for melt processing. The polymeric binders may be either hydrocarbon or non-hydrocarbon polymers. Preferably, the polymeric binder is an olefin-based polymer. The interfering components are those generally organic or inorganic materials utilized as fillers or additives in the polymer composite industry.
[0013] In another aspect of the invention, a preferred cellulosic material serves as the interfering component in the polymeric binder to form a polymeric mixture. In this aspect, the coupling agent incorporated into the melt processable material may include grafted polyolefins, di-block copolymers, tri-block copolymers, graft-block copolymers, random block copolymers, star-branched block copolymers, hyper-branched block copolymers, or silanes. Combinations of the noted coupling agents may also be employed with the polymer processing aid to reduce melt fracture of the polymeric binder during melt processing.
[0014] The present invention also contemplates methods for melt processing the novel compositions. Non-limiting examples of melt processes amenable to this invention include methods such as extrusion, injection molding, batch mixing and rotomolding.
[0015] The polymer processing aid and the coupling agent improve the melt processability of polymer composite systems. In particular, the present invention substantially improves the melt processability of interfering components that generally have a strong interfacial tension with polymeric binders. The novel combination enables a significant reduction in the interfacial tension between the polymeric binder and the interfering component thus resulting in an improved efficacy of the polymer processing aid. The resulting processed material exhibits a significant reduction in melt fracture as well as improved physical characteristics such as water uptake, flexural modulus, or tensile strength.
[0016] For purposes of the present invention, the following terms used in this application are defined as follows:
[0017] “Polymer processing aid” means a thermoplastic or elastomeric fluoropolymer that is capable of improving polymer processing, for example, reducing melt fracture.
[0018] “Polymeric binder” means a melt processable polymeric material.
[0019] “Interfering component” means a material that has a negative impact on polymer processing aid efficacy when incorporated with a polymeric binder.
[0020] “Coupling agent” means a material added to a polymer formulation to reduce interfacial tension between the polymer and the interfering component.
[0021] “Controlled polymer architecture” means block copolymers or block copolymers and polymers having a functional group on one chain end.
[0022] “Melt processable composition” means compositions or materials that are capable of withstanding processing conditions at temperatures near the melting point of at least one composition in a mixture.
[0023] “Block copolymer” means a polymer having at least two compositionally discrete segments, e.g. a di-block copolymer, a tri-block copolymer, a random block copolymer, a graft-block copolymer, a star-branched block copolymer or a hyper-branched block copolymer.
[0024] “Random block copolymer” means a copolymer having at least two distinct blocks wherein at least one block comprises a random arrangement of at least two types of monomer units.
[0025] “Di-block copolymers or Tri-block copolymers” means a polymer in which all the neighboring monomer units (except at the transition point) are of the same identity, e.g.,—AB is a di-block copolymer comprised of an A block and a B block that are compositionally different and ABC is a tri-block copolymer comprised of A, B, and C blocks, each compositionally different.
[0026] “Graft-block copolymer” means a polymer consisting of a side-chain polymers grafted onto a main chain. The side chain polymer can be any polymer different in composition from the main chain copolymer.
[0027] “Star-branched block copolymer” or “Hyper-branched block copolymer” means a polymer consisting of several linear block chains linked together at one end of each chain by a single branch or junction point, also known as a radial block copolymer.
[0028] “End functionalized” means a polymer chain terminated with a functional group on at least one chain end.
[0029] “Amphiphilic block copolymer” means a copolymer having at least two compositionally discrete segments, where one is hydrophilic and one is hydrophobic.
DETAILED DESCRIPTION OF THE INVENTION
[0030] The compositions of the present invention reduce the melt fracture encountered when melt processing polymeric binders containing interfering components. A coupling agent is employed in the melt processable composition in order to reduce interfacial tension between the polymeric binder and the interfering component. Thus the use of the coupling agent permits the fluoropolymer to function as intended thereby reducing melt fracture.
[0031] For purposes of the invention, melt processable compositions are those that are capable of being processed while at least a portion of the composition is in a molten state. Conventionally recognized melt processing methods and equipment may be employ in processing the compositions of the present invention. Non-limiting examples of melt processing practices include extrusion, injection molding, batch mixing, and rotomolding.
[0032] The polymeric binder functions as the host polymer of the melt processable composition. A wide variety of polymers conventionally recognized in the art as suitable for melt processing are useful as the polymeric binder. The polymeric binder includes substantially non-fluorinated polymers that are sometimes referred to as being difficult to melt process. They include both hydrocarbon and non-hydrocarbon polymers. Examples of useful polymeric binders include, but are not limited to, polyamides, polyimides, polyurethanes, polyolefins, polystyrenes, polyesters, polycarbonates, polyketones, polyureas, polyvinyl resins, polyacrylates and polymethylacrylates.
[0033] Preferred polymeric binders include polyolefins (high density polyethylene (HDPE), low density polyethylene (LDPE), linear low density polyethylene (LLDPE), polypropylene (PP)), polyolefin copolymers (e.g., ethylene-butene, ethylene-octene, ethylene vinyl alcohol), polystyrenes, polystyrene copolymers (e.g., high impact polystyrene, acrylonitrile butadiene styrene copolymer), polyacrylates, polymethacrylates, polyesters, polyvinylchloride (PVC), fluoropolymers, liquid crystal polymers, polyamides, polyether imides, polyphenylene sulfides, polysulfones, polyacetals, polycarbonates, polyphenylene oxides, polyurethanes, thermoplastic elastomers, epoxies, alkyds, melamines, phenolics, ureas, vinyl esters or combinations thereof. Most preferred are the polyolefins.
[0034] The polymeric binder is included in the melt processable compositions in amounts of about typically greater than about 30% by weight. Those skilled in the art recognize that the amount of polymeric binder will vary depending upon, for example, the type of polymer, the type of interfering component, the processing equipment, processing conditions and the desired end product.
[0035] Useful polymeric binders include blends of various thermoplastic polymers and blends thereof containing conventional additives such as antioxidants, light stabilizers, fillers, antiblocking agents, and pigments. The polymeric binder may be incorporated into the melt processable composition in the form of powders, pellets, granules, or in any other extrudable form.
[0036] The interfering component is generally any conventional filler or additive utilized in melt processing compositions that may adversely affect the efficacy of conventional polymer processing aids. In particular, interfering components may substantially affect the melt fracture of a melt processable composition. Non-limiting examples of interfering components include pigments, carbon fibers, hindered amine light stabilizers, anti-block agents, glass fibers, carbon black, aluminum oxide, silica, mica, cellulosic materials, or one or more polymers with reactive or polar groups. Examples of polymers with reactive or polar groups include, but are not limited to, polyamides, polyimides, functional polyolefins, polyesters, polyacrylates and methacrylates.
[0037] In one aspect of the invention, the interfering component is a cellulosic material. Cellulosic materials are commonly utilized in melt processable compositions to impart specific physical characteristics to the finished composition. Cellulosic materials generally include natural or wood materials having various aspect ratios, chemical compositions, densities, and physical characteristics. Non-limiting examples of cellulosic materials include wood flour, wood fibers, sawdust, wood shavings, newsprint, paper, flax, hemp, rice hulls, kenaf, jute, sisal, peanut shells. Combinations of cellulosic materials, or cellulosic materials with other interfering components, may also be used in the melt processable composition.
[0038] The amount of the interfering components in the melt processable composition may vary depending upon the polymeric binder and the desired physical properties of the finished composition. Those skilled in the art of melt processing are capable of selecting an appropriate amount of an interfering component to match a polymeric binder in order to achieve desired physical properties of the finished material. Typically, the interfering component may be incorporated into the melt processable composition in amounts up to about 80% by weight. Additionally, the interfering component, or components, may be provided in various forms depending on the specific polymeric binders and end use applications.
[0039] In accordance with the present invention, the combination of a coupling agent with a polymer processing aid significantly enhances the melt processing of a polymeric binder, particularly in the presence of an interfering component. In one aspect of the invention, a block copolymer coupling agent is employed with the polymer processing aid. In another aspect, a cellulosic interfering component is included in the melt processable composition along with the coupling agent and the polymer processing aid.
[0040] Conventionally recognized polymer processing aids may be suitable for use in the present invention. The polymer processing aids of this invention are generally formed by polymerizing one or more fluorinated olefinic monomers. Non-limiting examples of specific polymer processing aids, and the methods for producing those materials, are included in U.S. Pat. No. 5,830,947, U.S. Pat. No. 6,277,919 B1, and U.S. Pat. No. 6,380,313 B1, all herein incorporated by reference in their entirety. The resulting process aid contains greater than 50 weight percent fluorine, preferably greater than 60 weight percent, even more preferably greater than 65 weight percent.
[0041] The fluoropolymers made in this manner from these constituent olefin monomers may be either crystalline, semi-crystalline or amorphous in nature, though the preferred fluoropolymer process aids are crystalline or semi-crystalline. Additionally, the fluoropolymers may be bimodal as identified in U.S. Pat. No. 6,277,919, previously incorporated by reference.
[0042] The fluoropolymers should also contain essentially no ethylenic unsaturations because ethylenic unsaturations in the fluoropolymer may be sites for chemical attack by additives or other components present in the melt processable composition. This means that the fluoropolymers will contain very little ethylenic unsaturation (e.g., carbon-carbon double bonds) along their backbone or in their pendant chains or groups. While very low levels of ethylenic unsaturation in the fluoropolymer process aid may be tolerated without substantial effect in this invention, higher levels cannot be tolerated without risking the chemical stability of its fluoropolymer process aid.
[0043] Elastomeric or semi-crystalline fluoropolymers used in the invention should readily flow under the processing conditions of the polymeric binder or into which it is admixed. In matching the polymer process aid with a thermoplastic hydrocarbon polymeric binder, the fluoropolymer preferably should be chosen such that its melt viscosity matches or is about the same as the melt viscosity of the hydrocarbon polymer. For such matching, the polymer process aid can be selected such that the ratio of its melt viscosity to the melt viscosity of the thermoplastic hydrocarbon polymer is in the range of ratios from 0.01 to 100, more preferably in the range from 0.02 to 20, most preferably in the range between 0.05 and 5.
[0044] Crystalline fluoropolymers, for example polytetrafluoroethylene, used in the invention typically do not melt under conventional processing conditions. However, the crystalline fluoropolymers are capable of improving melt processability. Preferred levels of crystalline fluoropolymers are in the range of 0.1% to 3% by weight, and most preferably 0.25% to 1.0% by weight.
[0045] Preferred polymer process aids include one or more fluoropolymers with interpolymerized units derived from one or more monomers of tetrafluoroethylene, hexafluoropropylene, and vinylidene fluoride. With the preferred cellulosic interfering component, a polytetrafluoroethylene (PTFE) polymer processing aid is most preferred.
[0046] The amount of polymer processing aid present in the melt processable composition is dependent upon several variables, such as for example, the polymeric binder, the type and amount of interfering component, the type of melt processing equipment, the processing conditions, and others. Those of skill in the art are capable of selecting an appropriate amount of polymer processing aid to achieve the desired reduction of melt fracture. In a preferred embodiment, the polymer processing aid is used at 0.05 to 3.0% by weight of the composite. More preferably, the polymer processing aid level is between 0.1 and 2.0% and even more preferably between 0.25 and 1.0%.
[0047] Optionally, the polymer processing aid may contain lubricants that are utilized to impart specific performance or physical characteristics to either the polymer processing aid or the melt composition during melt processing. Non-limiting examples of lubricants include polyoxyalylene, polyolefin waxes, stearates, and bis-stearamides. A preferred embodiment is a composition containing polyoxyalkylene at 0.1 to 2.0 weight percent, more preferably 0.25 to 1.0 weight percent.
[0048] A coupling agent is a material added to a composite system comprised of a polymeric binder and an interfering component. In this invention, the combination of a coupling agent with a polymer processing aid has been found to have surprising synergistic effects. Although polymer processing aids are known in the art for their utility in improving the processability (i.e., increased throughput, reduced melt fracture) of thermoplastics when added at low levels (i.e., 200 to 2500 ppm), it has been found here that such materials can be highly ineffective in melt processable compositions containing an interfering component. Such interfering components can strongly interact with the polymer processing aid, thus rendering it ineffective by preventing it from coating the extruder and die wall during melt processing.
[0049] Preferred coupling agents of this invention include: functional polyolefins, silanes, titanates, zirconates, compositions having controlled polymer architecture, or combinations thereof. More preferred coupling agents of this invention include compositions having controlled polymer architecture.
[0050] Non-limiting examples of preferred compositions having controlled polymer architecture include di-block copolymers, tri-block copolymers, random block copolymers, graft-block copolymers, star-branched copolymers or hyper-branched copolymers. Additionally, block copolymers may have end functional groups.
[0051] Most preferred coupling agents of this invention are amphiphilic block copolymers. Amphiphilic block copolymers contain polar or reactive block and a non-polar block. Non-limiting examples of such materials include polystyrene-b-methacrylic anhydride, polystryrene-b-4-vinylpyridine, polyisoprene-b-methacrylic anhydride, polyisoprene-b-4-vinylpyridine, polybutadiene-b-methacrylic anhydride, polybutadiene-b-4-vinylpyridine, polyethylene-b-methacrylic anhydride, polyethylene-b-4-vinylpyridine, polyethylene-propylene-b-methacrylic anhydride, polyethylene-propylene-b-4-vinylpyridine, polystearylmethacrylate-b-methacrylic anhydride, polystearylmethacrylate-b-4-vinylpyridine, polybehenylmethacrylate-b-methacrylic anhydride, polybehenylmethacrylate-b-4-vinylpyridine or combinations thereof.
[0052] Non-limiting examples of specific block copolymer coupling agents, and the methods for producing those materials, are included in U.S. patent application Ser. No. 10/211,415, U.S. patent application Ser. No. 10/211,096, U.S. Pat. No. 6,448,353, and Anionic Polymerization Principles and Applications . H. L. Hsieh, R. P. Quirk, Marcel Dekker, NY, N.Y. 1996. Pg 72-127); all herein incorporated by reference in their entirety.
[0053] Polymers may be end-functionalized polymeric materials that may be synthesized by using functional initiators or by end-capping living polymer chains, as conventionally recognized in the art. The end-functionalized polymeric materials of the present invention may comprise a polymer terminated with a functional group on at least one chain end. The polymeric species may be a homopolymers, copolymers, or block copolymers. For those polymers that have multiple chain ends, the functional groups may be the same or different. Non-limiting examples of functional groups include amine, anhydride, alcohol, carboxylic acid, thiol, maleate, silane, and halide. End-functionalization strategies using living polymerization methods known in the art can be utilized to provide these materials.
[0054] The amount of coupling agent is dependent upon several variables, including the type and amount of interfering components, type and amount of polymeric binder, processing equipment and conditions. The preferred level of coupling agent ranges from greater than 0 to about 10 parts by weight of the composite. However, a more preferred coupling agent range is 0.05 to about 2 wt %.
[0055] In a most preferred embodiment of this invention, the polymeric binder is a polyolefin and the interfering component is a cellulosic material. The preferred coupling agent for such a composite is an amphiphilic block copolymer and the preferred polymer processing additive is a fluorothermoplastic. The cellulosic material typically comprises 20 to 70 wt % of the overall composite in this instance. The coupling agent and polymer processing additive are each loaded at levels between 0.1 and 1.0 wt %. Such wood composites find utility in a variety of commercial applications as building products and automotive components. One example is the use of such composites in residential and commercial decking applications.
[0056] In an alternative embodiment, conventional antimicrobial compositions may be added to the melt processing composition of the present invention. Antimicrobial compositions suitable for use with the present invention include those that are capable of withstanding the melt processing environment. Non-limiting examples of antimicrobials include thiabendazole, 2-(4-thiazolyl)benzimidazol, zinc pyrithione, zinc bis(2-pyridinethiol-1-oxide), zinc borate, barium metaborate, N-butyl-1,2-benzisothiazolin-3-one, 2-n-Octyl-4-isothiazolin-3-one, tetrachloroisophthalonitrile, 10,10′-Oxybisphenoxyarsine, N′-dichlorofluoromethylthio-N,N-dimethyl-N′(p-tolyl)-sulfamide, N-(trichloromethylthio)phthalimide, and 3-iodo-2-propynyl-n-butylcarbamate.
[0057] The melt processable composition of the invention can be prepared by any of a variety of ways. For example, the polymeric binder and the polymer processing additive can be combined together by any of the blending means usually employed in the plastics industry, such as with a compounding mill, a Banbury mixer, or a mixing extruder in which the processing additive is uniformly distributed throughout the host polymer. The processing additive and the host polymer may be used in the form, for example, of a powder, a pellet, or a granular product. The mixing operation is most conveniently carried out at a temperature above the melting point or softening point of the fluoropolymer, though it is also feasible to dry-blend the components in the solid state as particulates and then cause uniform distribution of the components by feeding the dry blend to a twin-screw melt extruder. The resulting melt-blended mixture can be either extruded directly into the form of the final product shape or pelletized or otherwise comminuted into a desired particulate size or size distribution and fed to an extruder, which typically will be a single-screw extruder, that melt-processes the blended mixture to form the final product shape.
[0058] Melt-processing typically is performed at a temperature from 180° to 280° C., although optimum operating temperatures are selected depending upon the melting point, melt viscosity, and thermal stability of the blend. Different types of melt processing equipment, such as extruders, may be used to process the melt processable compositions of this invention. Extruders suitable for use with the present invention are described, for example, by Rauwendaal, C., “Polymer Extrusion,” Hansen Publishers, p. 23-48, 1986. The die design of an extruder can vary, depending on the desired extrudate to be fabricated. For example, an annular die can be used to extrude tubing, useful in making fuel line hose, such as that described in U.S. Pat. No. 5,284,184 (Noone et al.), which description is incorporated herein by reference in its entirety.
[0059] The present invention enhances the melt processing of polymeric binders combined with interfering components. The coupling agent reduces the interfacial tension between the polymeric binders and the interfering component thereby permitting the polymer processing aid to provide a significant reduction in melt fracture of the processed composition.
[0060] The compositions of the present invention also enhance the physical properties of the processed material. For example, the processed material may exhibit improvements in water uptake, flexural modulus, or tensile strength. In a preferred embodiment, when the polymeric binder is polyethylene and the interfering component is a cellulosic material, the composition having at least one of a water uptake value of 3% or less, a flexural modulus of 2200 MPa or greater, or a tensile strength of 36 MPa or greater.
[0061] The melt processable compositions may be utilized to make items such as building materials and automotive components. Non-limiting examples include, residential decking and automotive interior components. Additionally, the compositions of the present invention may be used in film, sheet, pipe, wire or cable applications
[0062] The invention is further illustrated in the following examples.
EXAMPLES
[0063]
[0000]
Materials Used
Material
Description
HDPE
BH-53-35H, a high density polyethylene, commercially available
from Solvay, Houston, TX
Wood Flour
Oak wood flour, grade 4037, commercially available from American
Wood Fiber, Schofield, WI
Lubricant Package
A 50/50 blend of zinc stearate and ethylene bis-stearamide, each
commercially available from Aldrich Chemical Co., Milwaukee, WI.
Carbowax 8000
A polyethylene glycol, commercially available from Dow Chemical
Co., Midland, MI.
HALS
Chimassorb 944, a hindered-amine light stabilizer, commercially
available from Ciba Specialty Chemicals Corp., Tarrytown, NY.
Antiblock
Optiblock 10, commercially available from Specialty Minerals,
Easton, PA.
Pigment
Kronos 2075, commercially available from Kronos Inc., Houston,
TX.
ODMA-b-C4-b- t BMA
An ABC triblock copolymer, poly[octadecyl methacrylate-b-2-(N-
methylperfluorobutanesulfonamido)ethyl methacrylate-b-tert-butyl
methacrylate]. Synthesized using a stirred tubular reactor process as
described in U.S. Pat. No. 6,448,253 and U.S. application Ser. No.
10/211,0961A. Mn = 21 kg/mol, PDI = 2.63, 47/5/48
ODMA/C4/ t BMA by weight.
ODMA-b-C4-b-MAn
An ABC triblock copolymer, poly[octadecyl methacrylate-b-2-(N-
methylperfluorobutanesulfonamido)ethyl methacrylate-b-methacrylic
anhydride]. Synthesized from ODMA-b-C4-tBMA as described in
U.S. patent application Ser. No. 10/211,096.
PS-MAn
An AB diblock copolymer, poly[styrene-b-methacrylic anhydride].
Synthesized using a stirred tubular reactor process as described in U.S.
Pat. No. 6,448,253 and U.S. application Ser. No. 10/211,415. Mn = 125
kg/mol, PDI = 2.07, 96/4 PS/MAn by weight.
PS-PVP
An AB diblock copolymer, poly[styrene-b-4-vinylpyridine].
Synthesized using a stirred tubular reactor process as described in U.S.
Pat. No. 6,448,253. Mn = 25 kg/mol, PDI = 2.24, 95/5 PS/PVP by weight.
Polybond 3009
A maleated-polyethylene (~1 wt % maleic anhydride) commercially
available from Crompton Co., Middlebury, CT.
FX-5911
A fluoropolymer based processing aid, commercially available from
Dyneon LLC, Oakdale, MN.
PA-5933
A fluoropolymer additive, commercially available from Dyneon LLC,
Oakdale, MN.
FX-9613
A fluoropolymer based processing aid, commercially available from
Dyneon LLC, Oakdale, MN.
Test Methods
Tensile and Flexural Property Characterization
[0064] Test specimens were injection molded to specified dimensions as described below in the examples section. Tensile and flexural testing was subsequently performed on each sample using an Instron 5564 universal materials tester (commercially available from Instron Corporation, Canton, Mass.) as described in ASTM D1708 and D790, respectively. All samples were performed in triplicate.
Water Uptake Test
[0065] Injection molded samples (5″×1″×0.25″) of each test specimen were weighed and submerged in a container filled with deionized water for 720 hours. The resulting samples were removed from the container blotted dry to the touch and reweighed. The mass difference was utilized to determine the % water uptake. Each sample was run in duplicate and the average reported.
Composite Extrusion
[0066] Trial composite extrusion was carried out using a 19 mm, 15:1 L:D, Haake Rheocord Twin Screw Extruder (commercially available from Haake Inc., Newington, N.H.) equipped with a conical counter-rotating screw and a Accurate open helix dry material feeder (commercially available from Accurate Co. Whitewater, Wis.). The extrusion parameters were controlled and experimental data recorded using a Haake RC 9000 control data computerized software (commercially available for Haake Inc., Newington, N.H.). Materials were extruded through a standard ⅛″ diameter, 4-strand die (commercially available from Haake Inc., Newington, N.H.).
Comparative Example 1
Extrusion of 60/40 HDPE/Wood Flour Composite
[0067] Wood flour (800 g) was first pre-dried in a vacuum oven for 16 hr at 105° C. and ˜1 mmHg. HDPE (1200 g) was then dry mixed with the wood flour in a plastic bag until a relatively uniform mixture was achieved, and the blend was placed into the dry powder feeder. The material was fed into the extruder at a rate of 20 g/min (shear rate ˜30 s −1 ) and was processed using the following temperature profile in each respective zone: 160° C./180° C./180° C./190° C. The die was also kept at 190° C. throughout the experiment. Processing parameters (i.e., melt pressure, torque) were recorded throughout the experiment. The resulting material was collected and visually analyzed.
Comparative Example 2
Extrusion of 60/40 HDPE/Wood Flour Composite with a Lubricant Package
[0068] The experiment was prepared exactly as detailed in Comparative Example 1, with the exception that a 80 g of a lubricant package, consisting of 50 parts zinc stearate and 50 parts ethylene bis-stearamide was added to the formulation.
Comparative Examples 3-4
Extrusion of 60/40 HDPE/Wood Flour Composite a Coupling Agent
[0069] In Comparative Example 3, prior to the experiment, a masterbatch containing 95 parts HDPE and 5 parts poly(ODMA-C4-MAn) was made in the following fashion. HDPE (475 g) was dry mixed with poly(ODMA-C4- t BMA) (25 g) in a plastic bag until a relatively uniform mixture was achieved, and the blend was placed into the dry powder feeder. The material was fed into the extruder at a rate of 20 g/min (shear rate ˜30 s −1 ) and was processed using the following temperature profile in each respective zone: 200° C./240° C./240° C./240° C. The die was also kept at 240° C. throughout the experiment. The extruded strand was immediately cooled in a RT water bath and subsequently chopped into pellets using a Killion pelletizer. This masterbatch (200 g) was combined with HDPE (400 g) and pre-dried wood flour (400 g) and then dry mixed in a plastic bag until a relatively uniform mixture was achieved, and the blend was placed into the dry powder feeder. The material was fed into the extruder at a rate of 20 g/min (shear rate ˜30 s −1 ) and was processed using the following temperature profile in each respective zone: 160° C./180° C./180° C./190° C. The die was also kept at 190° C. throughout the experiment. Processing parameters (i.e., melt pressure, torque) were recorded throughout the experiment. The resulting material was collected and visually analyzed.
[0070] Comparative Example 4 was made in an identical fashion to comparative example 3 with the exception that the initial masterbatch was made using 100 g Polybond 3009 in place of ODMA-C4-MAn and 900 g HDPE and 400 g of it was combined with 200 g HDPE and 400 g dried wood flour in the composite formulation.
Comparative Example 5
Extrusion of 60/40 HDPE/Wood Flour Composite with a Polymer Processing Aid
[0071] Comparative example 5 was prepared exactly as detailed in Comparative Example 1, with the exception that 10,000 ppm of a polymer processing aid, Dynamar FX-5911, were respectively added to the formulation.
Example 1-2
Extrusion of 60/40 HDPE/Wood Flour Composite with a Polymer Processing Aid, and Coupling Agent
[0072] Example 1 was performed exactly as detailed in Comparative Example 4, with the exception that 1 g Dynamar FX-5911 was added to the formulation.
[0073] Example 2 was prepared exactly as detailed in Example 1 with the exceptions that 10 g of PS-b-MAn and 10 g of Dyneon PA-5933 were used in place of Polybond 3009 and Dynamar FX-5911, respectively and 40 g of Carbowax 8000 were also added to the formulation.
Example 3
Extrusion of 60/40 HDPE/Wood Flour Composite with a Polymer Processing Aid, Lubricant, and Coupling Agent
[0074] Example 3 was prepared exactly as detailed in Comparative Example 3, with the exception that 400 g of the masterbatch was combined 200 g of HDPE and 400 g of wood flour. Additionally, 1 g Dynamar PA-5933 and 40 g of Carbowax 8000 were also added to the formulation.
[0075] A summary of the formulations examined is given in Table 1.
[0000]
TABLE 1
Summary of Formulations for Comparative Examples 1-5 and Examples
1-3 (given in approximate parts per hundred by weight)
CE
CE
CE
CE
CE
Ex
Ex
Ex
Component
1
2
3
4
5
1
2
3
HDPE
60
60
60
60
60
60
60
60
Wood Flour
40
40
40
40
40
40
40
40
Carbowax 8000
—
—
—
—
—
—
2
2
Lubricant
—
4
—
—
—
—
—
—
PS-b-MAn
—
—
—
—
—
—
0.5
—
ODMA-b-C4-b-
—
—
1
—
—
—
—
2
MAn
Polybond 3009
—
—
—
4
—
4
—
—
Dyneon PA-
—
—
—
—
—
—
0.5
0.5
5933
Dynamar FX-
—
—
—
—
1.0
0.1
—
—
5911
[0076] Table 2 summarizes the processing results obtained for Comparative Examples 1-5 and Examples 1-3. The results demonstrate the utility of the present invention.
[0000]
TABLE 2
Summary of Processing Results for Comparative
Examples 1-5 and Examples 1-2
Melt Pressure
Torque
Example
(PSI)
(mg)
Melt Fracture
CE 1
1500
2900
yes
CE 2
1375
1925
yes
CE 3
1400
2750
yes
CE 4
1550
3300
yes
CE 5
1400
1850
yes
1
1000
2000
yes
2
1650
3300
no
3
850
1000
no
Comparative Example 6
Extrusion of LLDPE Containing 3000 ppm HALS with a Polymer Processing Aid
[0077] A masterbatch of HALS (3% in LLDPE, 200 g), Dynamar FX-9613 (2.8% in LLDPE, 93 g) and LLDPE (1707 g) were dry blended in a plastic bag until a relatively uniform mixture was achieved, and the blend was placed into the dry pellet/powder feeder. The material was fed into the extruder at a rate of 66 g/min (shear rate ˜115 s −1 ) and was processed using the following temperature profile in each respective zone: 190° C./190° C./190° C./190° C. The die was also kept at 190° C. throughout the experiment. Processing parameters (i.e., melt pressure, torque) were recorded throughout the experiment. The resulting material was collected and visually analyzed for the presence of melt fracture.
Example 4
Extrusion of LLDPE Containing 3000 ppm HALS, Processing Aid, and Coupling Agent
[0078] A masterbatch of HALS (3% in LLDPE, 200 g), PS-MAn (3.0% in LLDPE, 667 g) Dynamar FX-9613 (2.8% in LLDPE, 93 g), and LLDPE (1040 g) were dry blended in a plastic bag until a relatively uniform mixture was achieved, and the blend was placed into the dry pellet/powder feeder. The material was fed into the extruder at a rate of 66 g/min (shear rate ˜115 s −1 ) and was processed using the following temperature profile in each respective zone: 190° C./190° C./190° C./190° C./190° C. The die was also kept at 190° C. throughout the experiment. Processing parameters (i.e., melt pressure, torque) were recorded throughout the experiment. The resulting material was collected and visually analyzed for the presence of melt fracture.
Comparative Example 7
Extrusion of LLDPE Containing 15000 ppm Antiblock with a Polymer Processing Aid
[0079] A masterbatch of antiblock (60% in LLDPE, 50 g), Dynamar FX-9613 (2.8% in LLDPE, 93 g) and LLDPE (1857 g) were dry blended in a plastic bag until a relatively uniform mixture was achieved, and the blend was placed into the dry pellet/powder feeder. The material was fed into the extruder at a rate of 66 g/min (shear rate ˜115 s −1 ) and was processed using the following temperature profile in each respective zone: 190° C./190° C./190° C./190° C. The die was also kept at 190° C. throughout the experiment. Processing parameters (i.e., melt pressure, torque) were recorded throughout the experiment. The resulting material was collected and visually analyzed for the presence of melt fracture.
Example 5
Extrusion of LLDPE Containing 15000 ppm Antiblock, Polymer Processing Aid, and Coupling Agent
[0080] A masterbatch of antiblock (60% in LLDPE, 50 g), PS-MAn (3.0% in LLDPE, 667 g) Dynamar FX-9613 (2.8% in LLDPE, 93 g), and LLDPE (1190 g) were dry blended in a plastic bag until a relatively uniform mixture was achieved, and the blend was placed into the dry pellet/powder feeder. The material was fed into the extruder at a rate of 66 g/min (shear rate ˜115 s −1 ) and was processed using the following temperature profile in each respective zone: 190° C./190° C./190° C./190° C. The die was also kept at 190° C. throughout the experiment. Processing parameters (i.e., melt pressure, torque) were recorded throughout the experiment. The resulting material was collected and visually analyzed for the presence of melt fracture.
Comparative Example 8
Extrusion of LLDPE Containing 6000 ppm Pigment with a Polymer Processing Aid
[0081] A masterbatch of Dynamar FX-9613 (2.8% in LLDPE, 93 g), Pigment (12.0 g) and LLDPE (1895 g) were dry blended in a plastic bag until a relatively uniform mixture was achieved, and the blend was placed into the dry pellet/powder feeder. The material was fed into the extruder at a rate of 66 g/min (shear rate ˜115 s −1 ) and was processed using the following temperature profile in each respective zone: 190° C./190° C./190° C./190° C. The die was also kept at 190° C. throughout the experiment. Processing parameters (i.e., melt pressure, torque) were recorded throughout the experiment. The resulting material was collected and visually analyzed for the presence of melt fracture.
Example 6
Extrusion of LLDPE Containing 6000 ppm Pigment, Polymer Processing Aid, and Coupling Agent
[0082] A masterbatch of PS-MAn (3.0% in LLDPE, 667 g) Dynamar FX-9613 (2.8% in LLDPE, 93 g), Pigment (12.0 g) and LLDPE (1228 g) were dry blended in a plastic bag until a relatively uniform mixture was achieved, and the blend was placed into the dry pellet/powder feeder. The material was fed into the extruder at a rate of 66 g/min (shear rate ˜115 s −1 ) and was processed using the following temperature profile in each respective zone: 190° C./190° C./190° C./190° C. The die was also kept at 190° C. throughout the experiment. Processing parameters (i.e., melt pressure, torque) were recorded throughout the experiment. The resulting material was collected and visually analyzed for the presence of melt fracture.
[0083] A summary of the formulations for comparative examples 6-8 and examples 4-6 is given in Table 3. Composite formulations were made using standard extrusion processes. Throughout these experiments, the torque and melt pressure were monitored. The overall level of melt fracture of the sample produced was also noted.
[0000]
TABLE 3
Summary of Formulations for Comparative Examples
6-8 and Examples 4-6 (given in approximate
parts per million by weight in LLDPE)
Component
CE 6
CE 7
CE 8
Ex 4
Ex 5
Ex 6
HALS
3000
—
—
3000
—
—
Antiblock
—
15000
—
—
15000
—
Pigment
—
—
6000
—
—
6000
PS-b-MAn
—
—
—
10000
10000
10000
Dynamar FX-9613
500
500
500
500
500
500
[0084] Table 4 summarizes the processing results obtained for Comparative Examples 6-8 and Examples 4-6.
[0000]
TABLE 4
Summary of Processing Results for Comparative
Examples 6-8 and Examples 4-6
Melt Pressure
Torque
% Melt Fracture after 30
Example
(PSI)
(mg)
min
CE 6
2025
5875
50
CE 7
2025
5900
25
CE 8
1750
5450
15
4
1900
5500
15
5
1900
5200
5
6
1925
5150
5
[0085] As can be seen from this table, the addition of a coupling agent in combination with a PPA substantially reduces % melt fracture after 30 minutes processing.
[0086] An additional advantage of the invention described here is that the many of the composite compositions described have improved physical properties. This is exemplified in Examples 7-8.
Example 7-8
Extrusion of 60/40 HDPE/Wood Flour Composite with a Coupling Agent and a Polymer Processing Aid
[0087] Example 7. Wood flour (800 g) was first pre-dried in a vacuum oven for 16 hr @105° C. @˜1 mmHg. HDPE (1200 g), PS-b-PVP (40 g), and Dynamar FX-5911 (1 g) were then dry mixed with the wood flour in a plastic bag until a relatively uniform mixture was achieved, and the blend was placed into the dry powder feeder. The material was fed into the extruder at a rate of 20 g/min (shear rate ˜30 s −1 ) and was processed using the following temperature profile in each respective zone: 210° C./180° C./180° C./180° C. The die was also kept at 180° C. throughout the experiment. Processing parameters (i.e., melt pressure, torque) were recorded throughout the experiment. The resulting material was collected and visually analyzed.
[0088] The resulting pellets were injection molded into test specimens using a Cincinnati-Milacron-Fanuc Roboshot 110 R injection molding apparatus equipped with a series 16-I control panel (commercially available from Milacron Inc., Batavia, Ohio). The following experimental parameters were utilized. injection speed=120 mm/s, pack step=800 kg/cm 2 , step second: 6.0, shot size=42 mm, decompression distance=20 mm, decompression velocity=6.3 mm/s, cooling time=20.0 s, back pressure=80 kg/cm 2 , screw speed=60 rpm, cycle time=30 s, mold temperature=100° F., extruder zone temperatures=210° C., 210° C., 200° C., 200° C. In all cases, the first 10 shots were discarded. The remaining samples were tested for tensile and flexural properties.
[0089] Example 8 was performed exactly as described in Example 7, with the exception that PS-b-MAn was utilized in the place of PS-b-PVP.
[0090] Table 5 summarizes the compositions examined in Examples 7-8. Table 6 gives the flexural and tensile properties of these wood composite compositions 2, 7, and 8. This table also provides flexural and tensile properties for a lubricated wood composite formulation previously described (Comparative Example 2)
[0000]
TABLE 5
Summary of Formulations Examples 7-8 (given
in approximate parts per hundred by weight)
Component
7
8
HDPE
60
60
Wood Flour
40
40
PS-b-PVP
2
—
PS-b-Man
—
2
Dynamar FX-5911
0.5
0.05
[0000]
TABLE 6
Summary of Flexural and Tensile Properties for
Comparative Example 2 and Examples 2, 7, and 8.
Tensile
Flexural
Strength
Elongation at
Modulus
% Water
Melt
Example
(MPa)
Break (%)
(MPa)
Uptake
Fracture
CE 2
30.3
8.2
1845
3.6
Yes
2
39.3
7.6
2440
1.7
No
7
35.8
8.5
2215
1.6
No
8
37.0
8.1
2352
1.6
No
[0091] As is seen from this table, a >30% improvement in flexural and tensile properties and a >200% improvement in water uptake is observed for Examples 2, 7, and 8 when compared to Comparative Example 2.
[0092] From the above disclosure of the general principles of the present invention and the preceding detailed description, those skilled in this art will readily comprehend the various modifications to which the present invention is susceptible. Therefore, the scope of the invention should be limited only by the following claims and equivalents thereof. | A composition that employs a coupling agent with a fluoropolymer processing aid to address melt-processing issues related to the use of interfering components in melt-processable polymeric binders. | 2 |
FIELD OF THE INVENTION
The invention relates to the conversion of benzene by reaction with itself to produce higher molecular weight products which are liquid at ambient conditions. The conversion is catalytically effected by a zeolite of the class of medium pore size zeolites, sometimes circumscribed by the description of Constraint Index of 1 to 12.
BACKGROUND OF THE INVENTION
Few studies have been undertaken on the conversion of benzene. One possible explanation is the presumption that benzene is stable over acid catalysts. Some early work disputed that art held presumption. Cf. Frilette, V. J., and Rubin, M. K. "Journal of Catalysis" 4, p. 310-311, 1965. Karge, H. G., and Ladebeck, J., "Studies in Surface Science and Catalysis", #5, Proceedings of the International Symposium, 1980.
Although in the past there has been little incentive for studying its conversion to other products because of the high value of benzene as a basic petrochemical, anticipation of environmental regulations in gasoline has provided the incentive.
Various benzene conversions have been proposed such as alkylation with olefins, alcohols, or olefinic fragments from paraffin cracking, and interaromatic conversions such as xylene transalkylation. The common feature of these benzene reduction schemes is the use of another reactant.
The conversion discussed herein is catalyzed by zeolites. Naturally occurring and synthetic zeolites have been demonstrated to exhibit catalytic properties for various types of hydrocarbon conversions. Certain zeolites are ordered porous crystalline aluminosilicates having definite crystalline structure as determined by X-ray diffraction studies. Such zeolites have pores of uniform size which are uniquely determined by unit structure of the crystal. The zeolites are referred to as "molecular sieves" because the uniform pore size of a zeolite material may allow it to selectively absorb molecules of certain dimensions and shapes.
By way of background, one authority has described the zeolites structurally, as "framework" auminosilicates which are based on an infinitely extending three-dimensional network of AlO 4 and SiO 4 tetrahedra linked to each other by sharing all of the oxygen atoms. Furthermore, the same authority indicates that zeolites may be represented by the empirical formula
M.sub.2/n O.Al.sub.2 O.sub.3.xSiO.sub.2.yH.sub.2 O
In the empirical formula, M was described therein to be sodium, potassium, magnesium, calcium, strontium and/or barium; x is equal to or greater than 2, since AlO 4 tetrahedra are joined only to SiO 4 tetrahedra, and n is the valence of the cation designated M; and the ratio of the total of silicon and aluminum atoms to oxygen atoms is 1:2. D. Breck, ZEOLITE MOLECULAR SIEVES, John Wiley & Sons, New York p. 5 (1974).
The prior art describes a variety of synthetic zeolites. These zeolites have come to be designated by letter or other convenient symbols, as illustrated by zeolite Z (U.S. Pat. No. 2,882,243); zeolite X (U.S. Pat. No. 2,882,244); zeolite Y (U.S. Pat. No. 3,130,007); zeolite ZK-5 (U.S. Pat. No. 3,247,195); zeolite ZK-4 (U.S. Pat. No. 3,314,752); zeolite ZSM-5, its X-ray diffraction pattern, and its preparation are described in U.S. Pat. No. 3,702,886, the entire disclosure of which is incorporated by reference herein; zeolite ZSM-11 (U.S. Pat. No. 3,709,979) and zeolite SZM-23 (U.S. Pat. No. 3,076,842), merely to name a few.
ZSM-11 is described in U.S. Pat. No. 3,709,979. That description, and in particular the X-ray diffraction pattern of said ZSM-11, is incorporated herein by reference.
ZSM-12 is described in U.S. Pat. No. 3,832,449. That description, and in particular the X-ray diffraction pattern disclosed therein, is incorporated herein by reference.
ZSM-22 is described in U.S. patent application Ser. No. 373,451 filed Apr. 30, 1982, and now pending. The entire description thereof is incorporated herein by reference.
ZSM-23 is described in U.S. Pat. No. 4,076,842. The entire content thereof, particularly the specification of the X-ray diffraction pattern of the disclosed zeolite, is incorporated herein by reference.
ZSM-35 is described in U.S. Pat. No. 4,016,245. The description of that zeolite, and particularly the X-ray diffraction pattern thereof, is incorporated herein by reference.
ZSM-38 is more particularly described in U.S. Pat. No. 4,046,859. The description of that zeolite, and particularly the specified X-ray diffraction pattern thereof, is incorporated herein by reference.
ZSM-57 is a zeolite, the X-ray diffraction pattern and synthesis of which are described in EP 0,174,121.
It is to be understood that by incorporating by reference the foregoing patents and patent applications to describe examples of specific members of the novel class with greater particularity, it is intended that identification of the therein disclosed crystalline zeolites by resolved on tha basis of their respective X-ray diffraction patterns. It is the crystal structure, as identified by the X-ray diffraction "fingerprint", which establishes the identity of the specific crystalline zeolite material. The crystal structure of known zeolites may include gallium, boron, iron and chromium as framework elements, without changing its identification by the X-ray diffraction "fingerprint"; and these gallium, boron, iron and chromium containing silicates and aluminosilicates may be useful, or even preferred, in some applications described herein.
The members of the class of zeolites useful herein have an effective pore size of generally from about 5 to about 8 Angstroms, such as to freely sorb normal hexane. In addition, the structure must provide constrained access to larger molecules. It is sometimes possible to judge from a known crystal structure whether such constrained access exists. For example, if the only pore windows in a crystal are formed by 8-membered rings of silicon and aluminum atoms, then access by molecules of larger cross-section than normal hexane is excluded and the zeolite is not of the desired type. Windows of 10-membered rings are preferred, although, in some instances, excessive puckering of the rings or pore blockage may render these zeolite ineffective.
Although 12-membered rings in theory would not offer sufficient constraint to produce advantageous conversions, it is noted that the puckered 12-ring structure of TMA offretite does show some constrained access. Other 12-ring structures may exist which may be operative for other reasons, and therefore, it is not the present intention to entirely judge the usefulness of the particular zeolite solely from theoretical structural considerations.
A convenient measure of the extent to which a zeolite provides control to molecules of varying sizes to its internal structure is the Constraint Index of the zeolite. Zeolites which provide a highly restricted access to and egress from its internal structure have a high value for the Constraint Index, and zeolites of this kind usually have pores of small size, e.g. less than 5 Angstroms. On the other hand, zeolites which provide relatively free access to the internal zeolite structure have a low value for the Constraint Index, and usually pores of large size, e.g. greater than 8 Angstroms. The method by which Constraint Index is determined is described fully in U.S. Pat. No. 4,016,218, incorporated herein by reference for details of the method.
______________________________________ CI (at test temperature)______________________________________ZSM-4 0.5 (316° C.)ZSM-5 6-8.3 (371° C.-316° C.)ZSM-11 5-8.7 (371° C.-316° C.)ZSM-12 2.3 (316° C.)ZSM-20 0.5 (371° C.)ZSM-22 7.3 (427° C.)ZSM-23 9.1 (427° C.)ZSM-34 50 (371° C.)ZSM-35 4.5 (454° C.)ZSM-48 3.5 (538° C.)ZSM-50 2.1 (427° C.)TMA Offretite 3.7 (316° C.)TEA Mordenite 0.4 (316° C.)Clinoptilolite 3.4 (510° C.)Mordenite 0.5 (316° C.)REY 0.4 (316° C.)Amorphous Silica-alumina 0.6 (538° C.)Dealuminized Y 0.5 (510° C.)Erionite 38 (316° C.)Zeolite Beta 0.6-2.0 (316° C.-399° C.)______________________________________
The above-described Constraint Index is an important and even critical definition of those zeolites which are useful in the instant invention. The very nature of this parameter and the recited technique by which it is determined, however, admit of the possibility that a given zeolite can be tested under somewhat different conditions and thereby exhibit different Constraint Indices. Constraint Index seems to vary somewhat with severity of operations (conversion) and the presence or absence of binders. Likewise, other variables, such as crystal size of the zeolite, the presence of occluded contaminants, etc., may affect the Constraint Index. Therefore, it will be appreciated that it may be possible to so select test conditions, e.g. temperature, as to establish more than one value for the Constraint Index of a particular zeolite. This explains the range of Constraint Indices for some zeolites, such as ZSM-5, ZSM-11 and Beta.
It is to be realized that the above CI values typically characterize the specified zeolites, but that such are the cumulative result of several variables useful in the determination and calculation thereof. Thus, for a given zeolite exhibiting a CI value within the range of 1 to 12, depending on the temperature employed during the the test method within the range of 290° C. to about 538° C., with accompanying conversion between 10% and 60%, the CI may vary within the indicated range of 1 to 12. Likewise, other variables such as the crystal size of the zeolite, the presence of possibly occluded contaminants and binders intimately combined with the zeolite may affect the CI. It will accordingly be understood to those skilled in the art that the CI, as utilized herein, while affording a highly useful means for characterizing the zeolites of interest is approximate, taking into consideration the manner of its determination, with the possibility, in some instances, of compounding variable extremes. However, in all instances, at a temperature within the above-specified range of 290° C. to about 538° C., the CI will have a value for any given zeolite of interest herein within the approximate range of 1 to 12.
SUMMARY OF THE INVENTION
The invention relates to the catalytic reaction of benzene with iself to produce a mixture comprising primarily alkylbenzene and alkylnapthalenes, over a catalyst comprising a zeolite having a Constraint Index of 1 to 12. The catalyst allows for maintenance of high benzene conversion with reasonable aging rates as a consequence of a reduced tendency to form coke. In the absence of hydrogen minimal ring loss is observed, although aging rates are higher than when hydrogen is employed. Addition of hydrogen substantially reduces aging rate at the expense of increased selectivity to gas as a consequence of hydrocracking. The results obtained here represent a significant improvement over those obtained by Frilette and Rubin some 20 years ago with mordenite.
Application of the invention includes reduction of the benzene content of gasoline, and the preparation of petrochemical feedstocks.
DETAILED DESCRIPTION OF THE INVENTION
Catalytic conditions at which benzene reacts with itself include atemperature of 800°-1100° F.; a pressure of 100 to 1500 psig, preferably 300-800 psig, and a WHSV of 0.1 to 10 preferably 0.1 to 5. Hydrogen to hydrocarbon mole ratios (H 2 /HC) can range up to 5:1 and preferably up to 2:1.
As noted above, the catalyst for the benzene conversion comprises a zeolite. The zeolite is one which is characterized by a Constraint Index of 1 to 12. Preferably, the zeolite is ZSM-5, ZSM-11, ZSM-22 or ZSM-57. The zeolite most preferred is ZSM-5. ZSM-5 is a zeolite the Constraint Index of which measured at different temperatures but within the bounds of conversion specified varies but remains within the range of 1 to 12. Cf. Frillette et al, J. CATAL., Vol. 67, No. 1, 218 at 220 (1981). Coke production, with these catalysts is limited, and catalyst deactivation by coking is accordingly substantially nil. Preferably, the zeolite has an aplha value of at least 50. The Alpha value is an approximate indication of the catalytic cracking activity of the catalyst compared to a reference standard amorphous silica-alumina catalyst and it gives the relative rate constant (rate of normal hexane conversion per volume of catalyst per unit time). It is based on the activity of a highly active silica-alumina cracking catalyst taken as an Alpha of 1 (Rate Constant=0.016 sec -1 ). In the case of zeolite HZSM-5, only 174 ppm of tetrahedrally coordinated Al 2 O 3 are required to provide an Alpha Value of 1. The Alpha Test is described in U.S. Pat. No. 3,354,078 and in The Journal of Catalysis, Vol. IV, pp. 552-529 (August 1965).
Tha catalytic reaction can be undertaken in the presence or absence of hydrogen; and thus the H 2 /HC (feed) mole ratio can range from 0 to 5:1. Thus, the conversion does not require addition of hydrogen. However, if hydrogen is present, it reduces condensed ring(s) production and facilitates hydrocracking to light gas and reduces aging. In the absence of hydrogen, the process of the invention is applicable to naphthalene and m-naphthalene production for petrochemical use.
EXAMPLES
The primary catalyst was H-ZSM-5 (one crystal dimension of which is at most 0.5 microns), SiO 2 /Al 2 O 3 =40, 85% zeolite-15% Al 2 O 3 binder, 1/16 inch extrudate, alpha=500. Also used were three experimental catalysts. The first was a ZSM-5 zeolite co-crystallized with 4.6% gallium which was used as binder-free 20×60 mesh particles, and had a SiO 2 /(Al 2 O 3 +Ga 2 O 3 )=42 (Al 2 O 3 =0.29%). The other catalysts were 1/16 inch extruded, 35% Al 2 O 3 binder H-ZSM-4, SiO 2 /Al 2 O 3 =9, and a similarly extruded H-ZSM-23, SiO 2 /Al 2 O 3 =114, alpha=27. The catalysts were calcined in air at 900° F. prior to use.
Material balances were made by collection of the product stream in a liquid nitrogen-cooled trap and subsequent expansion of the gases into a precalibrated, constant volume glass system. Liquid and gas analysis were by GC. In some cases a large amount of condensed rings were generated. It is likely the methylnaphthalenes indicated in the data tables include higher condensed ring systems which form on the external catalyst surface. Thus the methyl-naphthalenes and C 13 + analysis are approximate.
The data in Tables 1 and 2 show that the benzene does react over non-metallic H-ZSM-5. The main products are C 7 -C 8 aromatics and naphthalenes as summarized below.
______________________________________ Wt % Conv.Prod. Dist., Wt % 26.8 53.8 Selectivity______________________________________C.sub.1 + C.sub.2 0.2 0.6 <--> 1.1Benzene 73.2 46.2 --Toluene 11.7 18.6 34.6C.sub.8 Ar 1.7 2.9 5.3C.sub.9 --C.sub.12 Ar 0.2 0.4 0.9Naphthalene 7.5 15.5 28.9m-Naphthalenes 5.6 13.7 25.4C.sub.13 + -- 0.6 3.9______________________________________
The aromatic ring is stable and only a small amount is lost to cracked products. However, the ring is quite reactive converting to C 7 -C 8 aromatics, condensed rings and coke. The latter two provide the hydrogen required to balance the stoichiometry. The pore size of ZSM-5 limits the growth of condensed rings permitting the products to leave the zeolite as liquid product. With larger pore materials which do not limit condensed ring growth, it is likely the reaction continues directly to coke resulting in rapid deactivation.
In the temperature range of 900°-950° F. and 1-2 WHSV, the conversion is substantial and there is probably little incentive to operate at higher temperatures which will accelerate coking. However, two other variables are important. First is pressure as seen below from Tables 1 and 2 at 945° F. and 1 WHSV.
______________________________________ Pressure, psig 100 500 800 Wt % of Conv.Selectivity 8.1 43.1 53.8______________________________________C.sub.1 --C.sub.6 1.9 1.5 1.1Toluene 53.4 41.7 34.6C.sub.8 Ar 4.5 4.9 5.3C.sub.9 --C.sub.12 Ar 0.4 0.7 0.8Naphthalene 24.6 28.9 28.9m-Naphthalenes 14.0 20.1 25.4C.sub.13 + 1.2 2.3 3.9______________________________________
The primary effect is on conversion which increases significantly with higher pressure. The selectivity also shifts from toluene to naphthalenes reflecting the pressure/conversion level changes.
TABLE 1______________________________________CONVERSION OF BENZENE OVER H-ZSM-5(on matrix) SiO.sub.2 /Al.sub.2 O.sub.3 ═40______________________________________Temperature, °F. 900.00 945.00 945.00Pressure, Psig 800.00 800.00 800.00WHSV 2.00 1.00 1.00H.sub.2.HC 0.00 0.00 0.00Material Balance 96.50 100.24 100.35Time on Stream. Hrs. 5.30 5.70 24.70Product Dist., Wt %C.sub.1 0.03 0.28 0.02C.sub.2 0.12 0.31 0.14C.sub.2 ═ 0.00 0.00 0.00C.sub.3 0.00 0.02 0.01C.sub.3 ═ 0.00 0.00 0.00ISO--C.sub.4 0.00 0.00 0.00N--C.sub.4 0.00 0.00 0.00C.sub.4 ═ 0.00 0.00 0.00ISO--C.sub.5 0.00 0.00 0.00N--C.sub.5 0.00 0.00 0.00C.sub.5 ═ 0.00 0.00 0.002.2 DM-C.sub.4 0.00 0.00 0.00Cyclo-C.sub.5 0.00 0.00 0.002,3 DM-C.sub.4 0.00 0.00 0.002-M-C.sub.5 0.00 0.00 0.003-M-C.sub.5 0.00 0.00 0.00N--C.sub.6 0.00 0.00 0.00C.sub.6 ═ 0.00 0.00 0.00M-Cyclo-C.sub.5 0.00 0.00 0.00Benzene 73.18 46.18 63.84Cyclo-C.sub.6 0.00 0.00 0.00C.sub.7 'S 0.00 0.00 0.00N--C.sub.7 0.00 0.00 0.00Toluene 11.71 18.60 14.10C.sub.8 'S 0.00 0.00 0.00N--C.sub.8 0.00 0.00 0.00C.sub.8 Ar. 1.65 2.87 1.61C.sub.9 + Par. 0.00 0.00 0.00C.sub.9 Ar 0.15 0.30 0.12C.sub.10 Ar. 0.07 0.14 0.10C.sub.10 --C.sub.12 Ar. 0.00 0.01 0.00Naphthalene 7.52 15.53 11.52M-Naphthalenes* ˜5.57 ˜13.65 ˜7.92C.sub.13 + 'S* 0.00 ˜2.10 ˜0.61Total Wt % Conv. 26.82 53.82 36.16Selectivity Wt %C.sub.1 --C.sub.3 0.56 1.13 0.47C.sub.4 --C.sub.6 0.00 0.00 0.00Toluene 43.66 34.56 38.99C.sub.8 Ar 6.15 5.33 4.45C.sub.9 Ar 0.56 0.56 0.33C.sub.10 --C.sub.12 Ar 0.26 0.28 0.28Naphthalene 28.04 28.86 31.86m-Napthalenes* 20.77 25.36 21.90C.sub.13 + 'S* 0.00 3.90 1.69______________________________________ *Condensed Aromatic Analysis Approximate.
The second important variable is hydrogen as seen in Table 2 and summarized below at 945° F., 500 psig, 1 WHSV.
______________________________________H.sub.2 /HC 0 2/1Wt % Conversion 43.1 47.6Product Dist., Wt % Selectivity Selectivity______________________________________C.sub.1 --C.sub.3 0.6 1.5 8.0 16.8C.sub.4 --C.sub.6 -- -- 0.1 0.2Benzene 57.0 -- 52.4 --Toluene 17.9 41.7 29.0 61.0C.sub.8 Ar 2.1 4.9 6.6 13.9C.sub.9 --C.sub.12 Ar 0.3 0.7 1.2 2.4Naphthalene 12.5 28.9 1.1 2.3m-Naphthalenes 8.7 20.1 1.6 3.3C.sub.13 + 1.0 2.3 0.1 0.2______________________________________
With hydrogen, naphthalenes are dramatically reduced since condensed ring make is no longer required to maintain hydrogen stoichiometry. At the same time, ring hydrocracking becomes significant, producing more light gas. Reducing the pressure to 100 psig lowers conversion but selectivities are approximately equivalent.
TABLE 2______________________________________CONVERSION OF BENZENE OVER H-ZSM-5 (on alumina)______________________________________Temperature, °F. 946.00 945.00 945.00 945.00 943.00Pressure, Psig 100.00 500.00 500.00 100.00 800.00WHSV 1.00 1.00 1.00 1.00 5.00H.sub.2.HC 0.00 0.00 2/1 2/1 0.4/1Material Balance 87.87 86.54 100.37 99.91 97.44Time on Stream. Hrs. 5.70 5.70 5.30 5.30 4.50Product Dist., Wt %C.sub.1 0.00 0.21 3.49 0.01 0.11C.sub.2 0.06 0.36 3.28 0.24 0.16C.sub.2 ═ 0.01 0.01 0.02 0.03 0.01C.sub.3 0.02 0.03 1.17 0.18 0.13C.sub.3 ═ 0.03 0.02 0.02 0.02 0.02ISO--C.sub.4 0.03 0.01 0.05 0.02 0.01N--C.sub.4 0.00 0.00 0.04 0.01 0.00C.sub.4 ═ 0.00 0.00 0.00 0.00 0.00ISO--C.sub.5 0.00 0.00 0.00 0.00 0.00N--C.sub.5 0.00 0.00 0.00 0.00 0.00C.sub.5 ═ 0.00 0.00 0.00 0.00 0.002.2 DM-C.sub.4 0.00 0.00 0.00 0.00 0.00Cyclo-C.sub.5 0.00 0.00 0.00 0.00 0.002,3 DM-C.sub.4 0.00 0.00 0.00 0.00 0.002-M-C.sub.5 0.00 0.00 0.00 0.00 0.003-M-C.sub.5 0.00 0.00 0.00 0.00 0.00N-- C.sub.6 0.00 0.00 0.00 0.00 0.00C.sub.6 ═ 0.00 0.00 0.00 0.00 0.00M-Cyclo-C.sub.5 0.00 0.00 0.00 0.00 0.00Benzene 91.95 56.95 52.39 94.94 88.68Cyclo-C.sub.6 0.00 0.00 0.00 0.00 0.00C.sub.7 'S 0.00 0.00 0.00 0.00 0.00N--C.sub.7 0.00 0.00 0.00 0.00 0.00Toluene 4.30 17.94 29.02 3.02 6.70C.sub.8 'S 0.00 0.00 0.00 0.00 0.00N--C.sub.8 0.00 0.00 0.00 0.00 0.00C.sub.8 Ar. 0.36 2.09 6.63 0.93 2.06C.sub.9 + Par. 0.00 0.00 0.00 0.00 0.00C.sub.9 Ar. 0.02 0.18 1.04 0.09 0.14C.sub.10 Ar. 0.01 0.11 0.11 0.01 0.06C.sub.10 --C.sub.12 Ar. 0.00 0.01 0.00 0.00 0.00Naphthalene 1.98 12.46 1.07 0.21 0.99M-Naphthalenes* 1.13 8.66 1.56 0.29 0.89C.sub.13 + 'S* 0.10 0.97 0.10 0.01 0.05Total Wt % Conv. 8.05 43.05 47.61 5.06 11.32Selectivity Wt %C.sub.1 --C.sub.3 1.49 1.46 16.76 9.49 3.80C.sub.4 --C.sub.6 0.37 0.02 0.19 0.59 0.09Toluene 53.42 41.67 60.95 59.68 59.19C.sub.8 Ar 4.47 4.85 13.93 18.38 18.20C.sub.9 Ar 0.25 0.42 2.18 1.78 1.24C.sub.10 --C.sub.12 Ar 0.12 0.26 0.23 0.20 0.53Naphthalene 24.60 28.94 2.25 4.15 8.75m-Naphthalenes* 14.04 20.12 3.28 5.73 7.86C.sub.13 + 'S* 1.24 2.25 0.21 0.20 0.44______________________________________ *M-Naphthalene and C.sub.13 + 'S Analysis Approximated.
Table 3 shows a brief aging run at 925° F., 800 psig, 1 WHSV and 2/1 H 2 /HC. At 60-65% conversion the aging rate is about 1.8° F./day permitting cycles of 1-2 months at these conditions.
TABLE 3__________________________________________________________________________BENZENE CONVERSION AND AGING OVERH-ZSM-5 (on alumina) WITH HYDROGENTemperature, °F. 924.00 924.00 924.00 923.00 923.00 923.00 924.00 949.00Pressure, Psig 800.00 800.00 800.00 800.00 800.00 800.00 800.00 800.00WHSV 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00H.sub.2.HC 2.10 2.10 2.10 2.10 2.10 2.10 2.10 2.10Material Balance 101.31 102.69 103.30 103.21 101.58 101.43 103.35 104.08Time on Stream-Hrs. 5.00 29.00 53.00 77.00 101.00 173.00 193.00 217.00Product Dist., Wt %C.sub.1 6.96 8.61 7.50 7.27 7.46 6.23 6.98 10.41C.sub.2 6.11 7.36 6.36 6.77 7.00 5.93 5.98 9.44C.sub.2 ═ 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00C.sub.3 1.34 1.36 1.36 1.49 1.62 1.57 1.58 1.25Benzene 38.01 34.04 36.49 35.76 35.68 39.37 38.99 28.68Cyclo-C.sub.6 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00C.sub.7 'S 0.00 0.00 0.01 0.01 0.00 0.00 0.00 0.00N-C.sub.7 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00Toluene 31.84 31.60 31.91 32.09 31.97 31.86 31.20 31.13C.sub.8 'S 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00N-C.sub.8 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00C.sub.8 Ar. 9.36 10.01 9.60 10.01 10.01 9.46 9.21 11.47C.sub.9 + Par. 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00C.sub.9 Ar. 1.51 1.64 1.45 1.55 1.56 1.56 3.12 1.89C.sub.10 Ar. 0.22 0.23 0.31 0.34 0.34 0.23 0.26 0.34C.sub.10 -C.sub.12 Ar. 0.01 0.01 0.01 0.01 0.00 0.01 0.02 0.02Naphthalene 1.73 1.93 1.96 1.78 1.64 1.44 1.41 1.88M-Naphthalenes* 2.73 3.06 2.91 2.80 2.63 2.26 2.16 3.35C.sub.13 +'S* 0.15 0.12 0.09 0.07 0.03 0.03 0.03 0.09Total Wt % Conv. 61.99 65.96 63.51 64.24 64.32 60.63 61.01 71.32Selectivity Wt %C.sub.1 -C.sub.3 23.25 26.27 23.96 24.17 25.00 22.60 22.19 29.58C.sub.4 -C.sub.6 0.05 0.08 0.05 0.09 0.09 0.10 0.10 0.04Toluene 51.36 47.91 50.24 49.95 49.70 52.55 51.14 43.65C.sub.8 Ar 15.10 15.18 15.12 15.58 15.56 15.60 15.10 16.08C.sub.9 Ar 2.44 2.49 2.28 2.41 2.43 2.57 5.11 2.65C.sub.10 -C.sub.12 Ar 0.37 0.36 0.50 0.54 0.53 0.40 0.46 0.50Naphthalene 2.79 2.93 3.09 2.77 2.55 2.38 2.31 2.64m-Napthalenes* 4.40 4.64 4.58 4.36 4.09 3.73 3.54 4.70C.sub.13 +'S* 0.24 0.18 0.14 0.11 0.05 0.05 0.05 0.13__________________________________________________________________________ *M-Naphthalenes and C.sub.13 +'S Analysis Approximate.
Table 4 shows results without hydrogen. As expected, aging is more severe because of the condensed ring make which facilitates coking. The aging rate is 5°-10° F./day at the 25% conversion level. By limiting conversion to this level it may be possible to obtain 1-2 week cycles operating in a swing reactor system.
TABLE 4______________________________________BENZENE CONVERSION AND AGINGOVER H-ZSM-5 (on alumina). NO H.sub.2.______________________________________Temperature, °F. 923.00 925.00 925.00Pressure, Psig 800.00 800.00 800.00WHSV 1.00 1.00 1.00H.sub.2.HC 0.00 0.00 0.00Material Balance 94.46 99.12 96.18Time on Stream. Hrs. 5.30 48.80 72.30Product Dist., Wt %C.sub.1 0.22 0.00 0.00C.sub.2 0.31 0.06 0.02Benzene 44.64 74.40 77.72Cyclo-C.sub.6 0.00 0.00 0.00C.sub.7 'S 0.00 0.00 0.00N--C.sub.7 0.00 0.00 0.00Toluene 19.91 10.33 9.16C.sub.8 'S 0.00 0.00 0.00N--C.sub.8 0.00 0.00 0.00C.sub.8 Ar. 3.19 1.30 1.21C.sub.9 + Par. 0.00 0.00 0.00C.sub.9 Ar. 0.36 0.09 0.06C.sub.10 Ar. 0.16 0.07 0.06C.sub.10 --C.sub.12 Ar. 0.01 0.00 0.00Naphthalene 15.34 8.21 7.15M-Naphthalenes* 13.98 5.26 4.42C.sub.13 + 'S* 1.87 0.28 0.20Total Wt % Conv. 55.36 25.60 22.28Selectivity Wt %C.sub.1 -- C.sub.3 0.99 0.23 0.09C.sub.4 --C.sub.6 0.00 0.00 0.00Toluene 35.96 40.35 41.11C.sub.8 Ar 5.76 5.08 5.43C.sub.9 Ar 0.65 0.35 0.27C.sub.10 --C.sub.12 Ar 0.31 0.27 0.27Naphthalene 27.71 32.07 32.09m-Naphthalenes* 25.25 20.55 19.84C.sub.13 + 'S* 3.38 1.09 0.90______________________________________ *M-Naphthalenes and C.sub.13 + 's Analysis Approximate.
Table 5 shows the results with [Ga]-ZSM-5. This catalyst does not respond to temperature and has low activity. Ga is known to promote aromatization which accounts for the increase in condensed rings and probably subsequent coking. Potentially it seems metals could facilitate this reaction by increasing the molecular hydrogen make thus reducing the need for condensed ring make. However, hydrogen make is favored at low pressure which is contrary to the requirement of higher pressure for benzene conversion.
TABLE 5______________________________________CONVERSION OF BENZENE OVER [Ga]-ZSM-5 (on alumina)______________________________________Temperature, °F. 900.00 953.00Pressure, Psig 800.00 800.00WHSV 2.00 1.10H.sub.2.HC 0.00 0.00Material Balance 103.22 92.96Time on Stream. Hrs. 5.40 5.70Product Dist., Wt %C.sub.1 0.01 0.01C.sub.2 0.02 0.03C.sub.2 ═ 0.00 0.00C.sub.3 0.03 0.02C.sub.3 ═ 0.00 0.01ISO--C.sub.4 0.01 0.02N--C.sub.4 0.03 0.00Benzene 95.39 91.52Cyclo-C.sub.6 0.00 0.00C.sub.7 'S 0.00 0.00N--C.sub.7 0.00 0.00Toluene 1.34 3.35C.sub.8 'S 0.00 0.00N--C.sub.8 0.00 0.00C.sub.8 Ar. 0.22 0.10C.sub.9 + Par. 0.00 0.00C.sub.9 Ar. 0.04 0.04C.sub.10 Ar. 0.04 0.05C.sub.10 --C.sub.12 Ar. 0.13 0.00Naphthalene 0.49 0.93M-Naphthalenes* ˜1.89 ˜3.36C.sub.13 + 'S* ˜0.36 ˜0.57Total Wt % Conv. 4.61 8.48Selectivity Wt %C.sub.1 --C.sub.3 1.30 0.71C.sub.4 --C.sub.6 0.87 0.12Toluene 29.07 39.50C.sub.8 Ar 4.77 1.18C.sub.9 Ar 0.87 0.47C.sub.10 --C.sub.12 Ar 3.69 0.59Naphthalene 10.63 10.97˜m-Naphthalenes* 41.00 39.62˜C.sub.13 + 'S* 7.81 6.72______________________________________ *m-Naphthalene and C.sub.13 + 's aromatic analysis approximate.
Two runs were made with a slightly more constrained zeolite, ZSM-23, Table 6, and a larger pore zeolite, ZSM-4, Table 7. Neither catalyst gave more than 1-2% conversion which is close to the thermal background. The ZSM-23 probably lacks sufficient activity to catalyze this reaction (alpha=27) and its unidimensional pore structure will tend toward rapid deactivation. ZSM-4 should have sufficient activity but probably the larger pore material will coke rapidly resulting in no long term activity for this reaction. This is in line with published data which show that conversion over mordenite decreases from 5% to less than 1% in less than 1.5 hours at atmospheric pressure (2). High pressures may favor even faster deactivation.
TABLE 6______________________________________BENZENE CONVERSION OVER H-ZSM-23______________________________________Temperature, °F. 951.00Pressure, Psig 800.00WHSV 1.00H.sub.2.HC 0.00Material Balance 89.36Time on Stream. Hrs. 3.50Product Dist., Wt %C.sub.1 0.00C.sub.2 0.00C.sub.2 ═ 0.00C.sub.3 0.00C.sub.3 ═ 0.00ISO--C.sub.4 0.00Benzene 98.55Cyclo-C.sub.6 0.00C.sub.7 'S 0.00N--C.sub.7 0.00Toluene 0.41C.sub.8 'S 0.00N--C.sub.8 0.00C.sub.8 Ar. 0.24C.sub.9 + Par. 0.00C.sub.9 Ar. 0.02C.sub.10 Ar. 0.02C.sub.10 --C.sub.12 Ar. 0.02Naphthalene 0.22M-Naphthalenes* 0.48C.sub.13 + 'S* 0.03Total Wt % Conv. 1.45Selectivity Wt % 0.00C.sub.1 --C.sub.3 0.00C.sub.4 --C.sub.6 0.00Toluene 28.28C.sub.8 Ar 16.55C.sub.9 Ar 1.38C.sub.10 --C.sub.12 Ar 2.76Naphthalene 15.17m-Naphthalenes* 33.10C.sub.13 + 'S* 2.07______________________________________ *M-Naphthalenes and C.sub.13 + 'S Analysis Approximate.
TABLE 7______________________________________BENZENE CONVERSION OVER H-ZSM-4______________________________________Temperature, °F. 944.00Pressure, Psig 800.00WHSV 1.00H.sub.2.HC 0.00Material Balance 93.62Time on Stream. Hrs. 5.90Product Dist., Wt %C.sub.1 0.00C.sub.2 0.00C.sub.2 ═ 0.00C.sub.3 0.00C.sub.3 ═ 0.00ISO--C.sub.4 0.03Benzene 98.70Cyclo-C.sub.6 0.00C.sub.7 'S 0.01N--C.sub.7 0.00Toluene 0.36C.sub.8 'S 0.00N--C.sub.8 0.00C.sub.8 Ar. 0.15C.sub.9 + Par. 0.00C.sub.9 Ar. 0.02C.sub.10 Ar. 0.00C.sub.10 --C.sub.12 Ar. 0.02Naphthalene 0.23M-Naphthalenes* 0.39C.sub.13 + 'S* 0.06Total Wt % Conv. 1.30Selectivity Wt %C.sub.1 --C.sub.3 0.00C.sub.4 --C.sub.6 4.62Toluene 27.69C.sub.8 Ar 11.54C.sub.9 Ar 1.54C.sub.10 --C.sub.12 Ar 1.54Naphthalene 17.69m-Naphthalenes* 30.00C.sub.13 + 'S* 4.62______________________________________ *M-Naphthalenes and C.sub.13 + 'S Analysis Approximate. | Benzene reacts with itself to produce liquid aromatic compounds having more than 6 carbon atoms, in the presence of zeolite characterized as a medium pore size and having an activity defined by an alpha value of at least 50. | 2 |
BACKGROUND
1. Field of the Invention
Embodiments of the present invention generally relate to nuclear medicine, and systems for obtaining images of a patient's body organs of interest. In particular, the present invention relates to a novel method and system for utilizing an adaptive framing protocol in medical imaging.
2. Description of the Related Art
Heart disease is very common. The heart can be evaluated for large vessel and small vessel disease. One by-product of small vessel heart disease is poor heart oxygenation.
Nuclear medicine is a unique medical specialty wherein radiation is used to acquire images that show the function and anatomy of organs, bones and/or tissues of the body. Radiopharmaceuticals are introduced into the body, either by injection or ingestion, and are attracted to specific organs, bones and/or tissues of interest. For example, the radiopharmaceutical (e.g., rubidium) is injected into the bloodstream.
The radiopharmaceutical produces gamma photon emissions that emanate from the body. One or more detectors are used to detect the emitted gamma photons and the information collected from the detector(s) is processed to calculate the position of origin of the emitted photon from the source (i.e., the body organ or tissue under study). The accumulation of a large number of emitted gamma positions allows an image of the organ or tissue under study to be displayed.
How fast the radiopharmaceutical is taken in by the heart indicates how quickly the heart is being oxygenated and also indicates how healthy the small micro-vessels are in the heart. The rate of absorption of the radiopharmaceutical is determined by comparing the amount of radiopharmaceutical at one time with the amount at another time.
To calculate the rate of absorption, measurements are taken at various times. Data is acquired for each patient under “rest” and “stress” conditions. Stress is usually induced through either some form of exertion (e.g., walking or running on a treadmill) or by injection of a chemical which increases the heart rate. The ratio between stress and rest in a healthy heart is about a factor of 4 and in a diseased heart the stress/rest ratio is about a factor of 1.2.
In PET studies of cardiac function, emission data are typically collected in list mode. The list is then divided into a predetermined temporal sequence of frames (using a framing protocol), an image is reconstructed from the data in each frame, and the sequence of reconstructed images analyzed for evidence of disease.
To date, framing protocols have universally been fixed for every patient. Clinicians choose some invariant sequence of framing times, which never changes. These fixed framing protocols are the same within each clinic.
For example, Lorte, Quantification of Myocardial Blood Flow with 82 Rb Dynamic PET Imaging , Eur. J. Nucl. Med. Mol. Imaging (2007) 34: 1765-1774, (“Lortie et al.”) analyzes all patient data using a framing protocol that consists of 17 frames organized as 12*10 s+2*30 s+1×60 s+1×120 s+1×240 s; and El Fakhri, Absolute Quantitation of Regional Myocardial Blood Flow ( MFB ) Using RB -82 PET: Experimental Validation Using Microspheres , J. Nucl. Med. 2007, 48 (Supplement 2) 54P, (“El Fakhri et al.”) analyzes all patient data using a framing protocol that consists of 34 frames organized as 24*5 s+6*10 s+4*20 s. In some studies, the first frame is started on a signal derived from the data, but in all studies the timing of the frames does not depend on any features of the data.
After image reconstruction, the amount of radioactivity in the heart can be measured.
One way to estimate dynamic physiological parameters from quantitative reconstructed images is given by Lortie et al., using a one-compartment model:
C m ( t )= K 1 e −k 2 t *C a ( t ) Equation (1)
where C a (t) and C m (t) are the measured concentrations of the radiotracer in the arterial blood and the tissue of interest, respectively. K 1 is a measure of how quickly the radiotracer flows into the tissue of interest and k 2 represents how quickly it flows out. To estimate the model parameters K 1 and k 2 , least squared error minimization can be used, with each frame assigned a weight proportional to its duration in time.
The prior art analyzes small vessel disease using a fixed framing protocol which often leads to an excessive number of frames used in the analysis.
Therefore, there exists a need in the art for a protocol which is adapted for each individual patient to minimize the number of frames used in the analysis of the medical images.
SUMMARY
These and other deficiencies of the prior art are addressed by embodiments of the present invention, for obtaining images of a patient's body organs of interest. In particular, the present invention relates to a novel method and system for utilizing an adaptive framing protocol in medical imaging. In one embodiment, the method acquires patient data. The peak value in the patient data is determined. The patient data is divided into two data segments (i.e., one data segment representing the data before the peak value occurs and a second data segment representing the patient data after the peak occurs). The slopes of the first and second data segments are calculated. Thereafter the slopes are used to determine an appropriate adaptive framing protocol. A number of frames and duration of each frame in the adaptive framing protocol can be calculated or the adaptive framing protocol can be selected from a plurality of framing protocols. Embodiments of the invention also include computer-readable mediums that contain features similar to the features in the above described method.
Other embodiments are also provided in which a computer-readable medium performs similar features recited by the above method.
BRIEF DESCRIPTION OF THE DRAWINGS
So that the manner in which the above recited features of the present invention can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments.
FIG. 1 depicts a graph in accordance with the prior art;
FIG. 2 depicts a data flow diagram in accordance with the prior art;
FIG. 3 depicts a fixed frame protocol in accordance with the prior art;
FIG. 4 depicts a graph in accordance with aspects disclosed herein;
FIG. 5 depicts another graph in accordance with aspects disclosed herein;
FIG. 6 depicts an embodiment of a data flow diagram in accordance with aspects disclosed herein;
FIG. 7 depicts a diagram of an exemplary method according to a preferred embodiment in accordance with aspects disclosed herein; and
FIG. 8 depicts an embodiment of a high-level block diagram of a computer architecture used in accordance with aspects disclosed herein.
To facilitate understanding, identical reference numerals have been used, wherever possible, to designate identical elements that are common to the figures.
DETAILED DESCRIPTION
In the following description, numerous specific details are set forth to provide a more thorough understanding of the invention. As will be apparent to those skilled in the art, however, various changes using different configurations may be made without departing from the scope of the invention. In other instances, well-known features have not been described in order to avoid obscuring the invention. Thus, the invention is not considered limited to the particular illustrative embodiments shown in the specification and all such alternate embodiments are intended to be included in the scope of the appended claims.
Aspects of this disclosure are described herein with respect to applying an adaptive framing protocol in PET systems. However, the description provided herein is not intended in any way to limit the invention to PET systems. Aspects of the material disclosed herein may be utilized in other imaging technologies (e.g., SPECT systems, etc.).
Although aspects of this disclosure are described herein with respect to blood flow through a heart, those descriptions are for exemplary purposes only and not intended in any way to limit the scope of the material disclosed herein. For example, the material disclosed herein may be used to examine blood flow through other organs/limbs/tissue (e.g., a toe, brain, etc.).
Some guidelines in selecting a framing protocol are (1) during initial phase of acquisition, when the data are changing rapidly, to divide the data into a large number of short flames, to capture the dynamics; (2) during a later phase of acquisition, when the data are changing slowly (when compared to the initial phase), to divide the data into a small number of long frames, to maximize noise performance; (3) to choose a framing protocol which behaves properly given the range dynamical behavior observed in all clinical data sets (i.e., from all patients); and (4) to minimize the overall number of frames so as to reduce the computational burden, and the time, needed by image reconstruction and analysis.
FIG. 1 (prior art) depicts a graph 100 of cardiac rubidium studies of two patients. Specifically, the graph 100 includes a “Y” axis 102 delineating a number of radioactive decay events and an “X” axis 104 delineating time in seconds. The graph 100 includes two cardiac rubidium plots (P 1 Rest 110 and P 1 Stress 108 ) for patient P 1 , and two cardiac rubidium plots (P 4 Rest 114 and P 4 Stress 112 ) for patient P 4 . The graph 100 also includes a legend 106 identifying each of the plots (“P 1 Rest,” “P 2 Stress,” “P 4 Rest,” and “P 4 Stress”) in graph 100 . Note that the P 1 Rest 110 and P 1 Stress 108 reach their peak before P 4 Rest 114 and P 4 Stress 112 . In other words, the level of radiotracer increases more rapidly for P 1 than for P 4 .
FIG. 2 depicts a data flow diagram 200 in accordance with a fixed framing protocol of the prior art. Specifically, the data flow diagram 200 includes PET event data 201 acquired from a patient. For illustrative purposes, the PET event data is the data (i.e., the plots P 1 Rest, P 1 Stress, P 4 Rest, and P 4 Stress) depicted in graph 100 . Fixed framing protocol 202 is a fixed framing protocol utilized by a clinic for all patients examined by the clinic. In this example of the prior art, the fixed framing protocol 202 includes eight segments (two 5 sec, two 10 sec, two 20 sec, and two 40 sec segments) depicted as look-up table 206 . The event data 201 is divided into eight list segments and mapped to a fixed framing protocol algorithm 202 . The length of each segment is predetermined in advance regardless of the dynamic data of an individual patient. The data in look-up table 206 is used by an image reconstruction module 204 . These list segments are then individually reconstructed as two 5 sec images, two 10 sec images, two 20 sec images, and two 40 sec images, yielding a fixed number of images 208 . Quantities extracted from the image sequence are then used to perform dynamic parameter estimation (e.g., using Equation (1)), yielding some physiological result 212 .
FIG. 3 depicts a fixed frame protocol 300 applied to graph 100 in accordance with the prior art. Specifically, FIG. 3 includes the “Y” axis 102 delineating the number of radioactive decay events and the “X” axis 104 delineating time in seconds. FIG. 3 also includes the two cardiac rubidium plots (P 1 Rest 110 and P 1 Stress 108 ) for patient P 1 , and the two cardiac rubidium plots (P 4 Rest 114 and P 4 Stress 112 ) for patient P 4 . In addition, the legend 106 identifying each of the plots (“P 1 Rest,” “P 2 Stress,” “P 4 Rest,” and “P 4 Stress”) is depicted.
This protocol is a fixed framing protocol and consists of 26 frames (i.e., twelve 5 sec, six 10 sec, four 20 sec, and four 40 sec frames). In this diagram the vertical lines 302 1 , 302 19 , . . . , 302 26 (collectively vertical lines 302 ) indicate the segments in time for subsequent analysis. The plots of patient P 1 peaks prior to the plots of patient P 4 . However, the fixed framing protocol doesn't take into account the faster increase in rubidium levels of P 1 relative to P 4 .
In general, the fixed framing leads to an excessive number of frames (before and after a peak occurs), since the high-frequency part at the beginning of the fixed protocol must be long enough to capture the activity peak in all studies, regardless of how late the peak occurs.
Aspects disclosed herein tailor the framing protocol to adapt to the observed peak in each individual data set, by performing a fast, preliminary analysis of the data while it is still in list mode. The adaptive framing protocol samples at the appropriate frequency around peak activity and at lower frequency after the peak. As a result, the number of frames utilized by this method is significantly less than the number of frames required by the fixed framing method, with little or no loss of dynamic resolution.
FIG. 4 depicts a graph 400 in accordance with aspects disclosed herein. Specifically, FIG. 4 includes the “Y” axis 102 delineating the number of radioactive decay events and the “X” axis 104 delineating time in seconds. FIG. 4 also includes the two cardiac rubidium plots (P 1 Rest 110 and Pt Stress 108 ) for patient P 1 . In addition, a legend 404 identifying both plots for P 1 is depicted. FIG. 4 illustrates the results of an adaptive framing protocol applied to P 1 Rest 110 and P 1 Stress 108 . The data, while still in list mode, is analyzed (using e.g., a polynomial approximation) to determine when a peak value occurs. As a result, short sequences are applied before the determined peak value and longer sequences are applied after the determined peak.
In FIG. 4 , the adaptive protocol includes fourteen frames (( 402 1 , . . . , 402 11 , . . . , and 402 14 ) collectively frames 402 ). Because P 1 Rest 110 and P 1 Stress 108 peak earlier than P 4 Rest 114 and P 4 Stress 112 shorter frames can be applied to P 1 Rest 110 and P 1 Stress 108 up to the determined peak and longer sequences can be applied after the determined peak. In the sharply peaked case of patient P 1 , a smaller number (relative to patient P 4 ) of high frequency frames are used prior to peak.
FIG. 5 depicts another graph 500 in accordance with aspects disclosed herein. Specifically, FIG. 5 includes the “Y” axis 102 delineating the number of radioactive decay events and the “X” axis 104 delineating time in seconds. FIG. 5 also includes the two cardiac rubidium plots (P 4 Rest 114 and P 4 Stress 112 ) for patient P 4 . In addition, a legend 504 identifying both plots for P 4 is depicted.
FIG. 5 illustrates the results of an adaptive framing protocol applied to P 4 Rest 114 and P 4 Stress 112 . The data for P 4 , while still in list mode, is analyzed (using e.g., a polynomial approximation) to determine when a peak value occurs. The plots for patient P 4 peak slower (than patient P 1 ) which allows lower frequency frames (i.e., fewer frames) before peak occurs.
In FIG. 5 , the adaptive protocol includes twelve frames (( 502 1 , . . . , 502 9 , . . . , and 502 12 ) collectively frames 502 ). Because P 1 Rest 110 and P 1 Stress 108 peak earlier than P 4 Rest 114 and P 4 Stress 112 shorted frames can be applied to P 1 Rest 110 and P 1 Stress 108 up to the determined peak and longer sequences can be applied after the determined peak. Juxtaposition (not shown) of FIGS. 4 and 5 shows the differences between the framing protocols (i.e., frames 402 and 502 ) utilized to analyze patients P 1 and P 4 respectively.
FIG. 6 depicts a data flow diagram 600 in accordance with aspects disclosed herein. Specifically, the data flow diagram 600 includes PET event data 201 acquired from all of the patients. For illustrative purposes, the PET event data is the data (i.e., the plots P 1 Rest, P 1 Stress, P 4 Rest, and P 4 Stress) depicted in graph 100 . An adaptive framing module 602 is separately applied to the data for each patient (i.e., applied to patient P 1 and P 4 separately).
Illustratively, the adaptive framing module 602 is depicted as being one of two different framing protocols (framing protocols 604 and 606 ). However, that depiction is not intended in any way to limit the scope of the invention. For example, the adaptive framing module 602 may contain more than two framing protocols.
Framing protocol 604 includes four frames (four 5 sec, one 10 sec, one 20 sec, and one 30 sec frames) and framing protocol 606 includes four frames (one 10 sec one 20 sec, one 30 sec, and one 40 sec frames). The number of frames is for illustrative purposes only and is used to depict that there is a difference between framing protocols 604 and 606 .
After analyzing a patient's data, a determination is made which framing protocol is the most appropriate framing protocol to utilize for the patient. After the determination is made which of the framing protocols is the most appropriate the data can be subsequently analyzed by an image reconstruction module 608 . These list segments are then individually reconstructed into image lists (in this example depicts as one of two image lists 610 and 612 corresponding to the adaptive framing protocol previously selected). Quantities extracted from the image sequence are then used to perform dynamic parameter estimation by the dynamic parameter module 614 , yielding some physiological result 616 .
FIG. 7 depicts an exemplary method 700 in accordance with embodiments disclosed herein. The method 700 begins at step 702 .
After step 702 , the method 700 proceeds towards step 704 . At step 704 , a patient's data is acquired. The patient data may be acquired from memory, transmitted from a remote device, or transmitted towards a processor. The patient data includes the number of radioactive decay events (for both stress and rest) and the times at which the events occurred. After, the acquisition step 704 , the method 700 proceeds towards step 706 .
At step 706 , a peak value (i.e., the highest value) of the acquired patient data is determined. After determination of the peak value, the method 700 proceeds towards step 708 .
At step 708 , the peak value is used to divide the patient's data into two temporal segments (i.e., one segment including all data before the peak value occurs and the other segment including all data after the peak value occurs). After step 708 , the method 700 proceeds towards step 710 .
At step 710 , the method 700 analyzes the segment which includes the data that occurred before the peak value. A subset of points which are both close to the peak value and greater than 10% of the maximum. The rising slope (i.e., the slope prior to and approaching peak) is calculated (e.g., using linear regression). After step 710 , the method 700 proceeds towards step 712 .
At step 712 , the slope (i.e., a declining slope) after the peak value has occurred is calculated. Although various calculations may be used to determine the slope after the peak value has occurred, illustratively the slope is calculated using Equations (2) and (3) below. The best fit to a decaying exponential can be calculating using Equation (2):
f ( t )= Ae −st Equation (2)
where f(t) represents the data, A represents an initial value, e represents the natural base, t is time, and s is a decay parameter that indicates the rate at which the data values declines (i.e., the slope) after the peak.
There are various ways to calculate the decay parameter s. For example, the decay parameter s may be calculated using Equation (3):
s = n ∑ t i ≥ p ( t i ln ( f ( t i ) ) ) - ∑ t i ≥ p t i ∑ t i ≥ p ln ( f ( t i ) ) ∑ t i ≥ p t i 2 - ( ∑ t i ≥ p t i ) 2 Equation ( 3 )
where s is the decay parameter (i.e., the slope), t is time, n is the number of data points following the peak value, the summation is taken over t≧p (where p is the peak value), and f(t) denotes the data. After calculation of the declining slope, the method 700 proceeds towards step 714 .
At step 714 , a framing protocol is selected based upon the properties of the data. The number of frames and the parameters of the frames (offset in time and frame duration) may change in response to the measured position in time and sharpness in time of the peak in the data. In various embodiments, the framing protocol is selected from a group of framing protocols stored in memory (e.g., stored in a look-up table). In other embodiments, the number of frames, in the framing protocol, and their durations may be calculated. Thereafter the method 700 proceeds towards and ends at step 716 .
Although method 700 is described as calculating the rising slope prior to calculating the declining slope that description is not intended in any way to limit the scope of the invention. For example, in various embodiments, the declining slope may be calculated before the rising slope.
FIG. 8 depicts a high-level block diagram of a general-purpose computer architecture 800 for providing an adaptive framing protocol. For example, the general-purpose computer 800 is suitable for use in performing the method of FIG. 7 . The general-purpose computer of FIG. 8 includes a processor 810 as well as a memory 804 for storing control programs and the like. In various embodiments, memory 804 also includes programs (e.g., depicted as an “adaptive framing module” 812 for determination of a framing protocol based on the properties of the data) for performing the embodiments described herein. The processor 810 cooperates with conventional support circuitry 808 such as power supplies, clock circuits, cache memory and the like as well as circuits that assist in executing the software routines 806 stored in the memory 804 . As such, it is contemplated that some of the process steps discussed herein as software processes may be loaded from a storage device (e.g., an optical drive, floppy drive, disk drive, etc.) and implemented within the memory 804 and operated by the processor 810 . Thus, various steps and methods of the present invention can be stored on a computer readable medium. The general-purpose computer 800 also contains input-output circuitry 802 that forms an interface between the various functional elements communicating with the general-purpose computer 800 .
Although FIG. 8 depicts a general-purpose computer 800 that is programmed to perform various control functions in accordance with the present invention, the term computer is not limited to just those integrated circuits referred to in the art as computers, but broadly refers to computers, processors, microcontrollers, microcomputers, programmable logic controllers, application specific integrated circuits, and other programmable circuits, and these terms are used interchangeably herein. In addition, although one general-purpose computer 800 is depicted, that depiction is for brevity on. It is appreciated that each of the methods described herein can be utilized in separate computers.
The invention having been described, it will be apparent to those skilled in the art that the same may be varied in many ways without departing from the spirit and scope of the invention. In particular, while the invention has been described with reference to utilizing Equations (2) and (3), the inventive concept does not depend upon the use of Equations (2) and (3). Any acceptable methods may be used determine the slope before peak value and the slope after peak value. As previously explained adaptive framing may be performed by a programmable computer loaded with a software program, firmware, ASIC chip, DSP chip or hardwired digital circuit. Any and all such modifications are intended to be included within the scope of the following claims.
While the foregoing is directed to embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow. | Methods and computer-readable mediums are provided. In one embodiment, the method acquires patient data. The peak value in the patient data is determined. The patient data is divided into two data segments (i.e., one data segment representing the data before the peak value occurs and a second data segment representing the patient data after the peak occurs). The slopes of the first and second data segments are calculated. Thereafter the slopes are used to determine an appropriate adaptive framing protocol. A number of frames and duration of each frame in the adaptive framing protocol can be calculated or the adaptive framing protocol can be selected from a plurality of framing protocols. Embodiments of the invention also include computer-readable mediums that contain features similar to the features in the above described method. | 0 |
FIELD
The invention relates generally to optimizing bi-directional communication in a network. In particular, the invention relates to optimizing bi-directional communication in an information centric network by reducing packet traffic quantity and processing time.
BACKGROUND
Internet usage patterns have changed markedly since the advent of high speed data connectivity. Data creation, dissemination and access drive most traffic on the Internet, causing a greater focus on acquiring data as needed regardless of the source of the data. Such evolving usage models have put significant pressure on the prevalent internet infrastructure, much of which was originally designed around a host-centric model. For example, in the present model, to acquire data, consumer systems need to be aware of the source of the desired data. Such data may additionally be difficult to authenticate, as current models do not provide built in mechanisms for verifying data authenticity, which may, in turn, lead to issues such as spamming or phishing.
To address some of these problems, an Information Centric Networking (ICN) approach was developed to re-design the current Internet to move away from the “host-centric” model to a “data-centric” model. ICN seeks to make data the primary design target, rather than its location.
ICN approaches, then, seek to remove many of the issues in the current Internet, particularly in the areas of data delivery, security and mobility. Most, if not all, ICN approaches operate on a pull model, driven by a data receiver. These approaches may seek to define security and mobility as core features of the network, rather than have them as overlays.
However, existing ICN models may be inefficient in the area of bi-directional real-time communications. In classical ICN approaches, each participant sends a request message for any data that they require. The network or the targeted entity then sends back the requested data as a response. However, for real-time bidirectional multi-media communications, this pull-based model introduces significant overheads due to increased traffic and processing of a much larger number of packets at the network elements.
Real Time Communication (RTC) applications, for example, a voice-over-IP (VoIP) call, may require a continuous stream of voice packets, to be exchanged between participating parties for an extended period of time. Delivery of these data may have real-time constraints. Failure to meet these constraints can lead to severe degradation of call quality. In standard VoIP implementations, both parties may stream voice packets to the other side as soon as they receive a signaling confirmation that the other end is ready to receive media. Thus, media exchange occurs in a push model, in contrast to the pull model in ICN approaches.
Using Pull type architecture is problematic for real-time applications due to performance and processing overheads. Some adaptations exist, such as methods for pipelining, where requests are sent in advance to availability of data, thereby reducing latencies that may occur if the parties to the call had to wait for requests from the other end before they can send media. Even with such changes, however, transmitting bi-directional real-time traffic has significant overheads.
Specifically, existing approaches may impose significant network overhead. In an RTC application, like a VoIP conference call, all involved parties send as well as receive data. In VoIP this may be achieved by creating one outgoing real-time transport protocol (“rtp”) stream and one incoming rtp stream for each user. In an ICN model, each user may need to send a request for the other parties' data, and send data in response to the other parties' request. Consequently, every data packet to be sent needs a corresponding request packet. In a n-user conference, traditional VoIP will require setting up 2*n rtp streams, while a similar implementation in an existing ICN model may require 4*n streams, effectively reducing available bandwidth to half.
Existing ICN approaches may impose a processing overhead. Most normal processing operations involving the request and data packets in existing ICN models are not necessary for RTC applications. Cache lookups while processing requests and cache updates while forwarding data packets, for example, may be superfluous given that data is transient in real-time communications. Also, the requirement to have a request precede the receipt of any content may result in increased packet processing overhead as they have to process double the number of packets.
Accordingly, there is a need for a data centric approach to bi-directional communications that addresses the above problems.
SUMMARY
Embodiments of the present invention include a computer implemented method for enhanced bi-directional communication in an information centric computer network, the method comprising receiving, by a computing apparatus, one or more requests for data from at least one of a remote node and a client application on the computing apparatus and switching to a piggyback session by the computing apparatus. As disclosed, the piggyback session may comprise mapping the one or more requests for data received to content, sending at least one piggyback packet, by the computing apparatus, to the remote node, wherein a piggyback packet is a data packet comprising a request field and a content field, receiving at least one piggyback packet from the remote node, processing one or more piggyback packets. In accordance with at least one embodiment, the processing may comprise splitting the request field and the content field in at least one received piggyback packet, sending the content extracted from the received piggyback packet to a client application running on the computing apparatus and setting one or more events to trigger the processing of at least one piggyback packet.
In another embodiment, a computer implemented method for enhancing bi-directional communication by a router device in an information centric network is described. In accordance with the described embodiment, the method may comprise validating an incoming packet by the router device, wherein the packet comprises a content field and a request field, checking a processor readable memory at the router device for a stored request entry that matches content in the incoming packet, creating an entry in a processor readable memory at the router device for the embedded request in the packet, determining one or more router interfaces for forwarding data from the incoming packet to a remote client device, determining one or more router interfaces for forwarding a request from the incoming packet to a remote client device, and forwarding the incoming packet to one or more overlapping router interfaces. An overlapping router interface is a determined router interface for forwarding the data from the incoming packet and is also a determined router interface for forwarding a request from an incoming packet. An additional step discloses splitting the incoming packet into a request packet and a data packet if no overlapping router interfaces exist.
In another embodiment, a machine comprising a processor and a processor readable memory which contains data representing a packet data structure is described. The packet data structure may comprise a first field, the first field comprising a content object. The content object includes a content name and an authentication field, wherein the authentication field comprises a set of authentication information selected from a group consisting of a cryptographic key and a cryptographic signature, and, additionally, a data field. The packet data structure also comprises a second field with a request object, wherein the request object includes a request name.
DRAWINGS
These and other features, aspects, and advantages of the present invention will be better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:
FIG. 1 is an illustration of an exemplary computing architecture involved in the optimization of bi-directional communication, in accordance with an embodiment.
FIG. 2 is an illustrative diagram of a piggyback packet, in accordance with an embodiment.
FIG. 3 is a flowchart illustrating aspects of a method for optimizing bi-directional communication, in accordance with an embodiment.
FIGS. 4 a and 4 b are flowcharts illustrating steps involved in a piggyback session, in accordance with an embodiment.
FIG. 5 is a flowchart illustrating the optimization of bi-directional communications at a router device, in accordance with an embodiment.
FIG. 6 is a schematic diagram of the processing of a piggyback packet at a client side device, in accordance with an embodiment.
FIG. 7 is a flow diagram illustrating responses, by a client stack, to different packet reception events in a piggyback session in accordance with an embodiment.
While systems and methods are described herein by way of example and embodiments, those skilled in the art recognize that systems and methods for enhanced bi-directional communication in an information centric network are not limited to the embodiments or drawings described. It should be understood that the drawings and description are not intended to be limiting to the particular form disclosed. Rather, the intention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the appended claims. Any headings used herein are for organizational purposes only and are not meant to limit the scope of the description or the claims. As used herein, the word “may” is used in a permissive sense (i.e., meaning having the potential to) rather than the mandatory sense (i.e., meaning must). Similarly, the words “include”, “including”, and “includes” mean including, but not limited to.
DETAILED DESCRIPTION
The following description is the full and informative description of the best method and system presently contemplated for carrying out the present invention which is known to the inventors at the time of filing the patent application.
Embodiments of the present invention may combine disabling of caching with an intelligent exploitation of the bidirectional nature of the real-time traffic to reduce both computational and network overheads involved in an ICN approach to support real time communications. In accordance with some embodiments, future requests piggy back on data sent in response to requests from the far-end. To accomplish this, present implementations include a ‘piggyback packet’ which contains both data and request fields in the same packet. By sending a single piggyback packet instead of separate request and data packets, both network and processing overhead may be reduced.
Firstly, with reference to FIG. 1 , a computing environment in which present implementations may be executed is described. With reference to FIG. 1 , the computing environment 100 includes at least one processing unit 110 and memory 120 . The processing unit 110 executes computer-executable instructions and may be a real or a virtual processor. In a multi-processing system, multiple processing units execute computer-executable instructions to increase processing power. The memory 120 may be volatile memory (e.g., registers, cache, RAM), non-volatile memory (e.g., ROM, EEPROM, flash memory, etc.), or some combination of the two. In some embodiments, the memory 120 stores software 150 implementing described techniques.
A computing environment may have additional features. For example, the computing environment 100 includes storage 140 , and one or more communication connections 130 . An interconnection mechanism (not shown) such as a bus, controller, or network interconnects the components of the computing environment 100 . Typically, operating system software (not shown) provides an operating environment for other software executing in the computing environment 100 , and coordinates activities of the components of the computing environment 100 .
The storage 140 may be removable or non-removable, and includes magnetic disks, magnetic tapes or cassettes, CD-ROMs, CD-RWs, DVDs, or any other medium which may be used to store information and which may be accessed within the computing environment 100 . In some embodiments, the storage 140 stores instructions for the software 150 .
Some embodiments may include one or more input devices and one or more output devices. The input device(s) may be a touch input device such as a keyboard, mouse, pen, trackball, touch screen, or game controller, a voice input device, a scanning device, a digital camera, or another device that provides input to the computing environment 100 . The output device(s) may be a display, printer, speaker, or another device that provides output from the computing environment 100 .
The communication connection(s) 130 enable communication over a communication medium to another computing entity. The communication medium conveys information such as computer-executable instructions, audio or video information, or other data in a modulated data signal. A modulated data signal is a signal that has one or more of its characteristics set or changed in such a manner as to encode information in the signal. By way of example, and not limitation, communication media include wired or wireless techniques implemented with an electrical, optical, RF, infrared, acoustic, or other carrier.
Implementations may be described in the general context of computer-readable media. Computer-readable media are any available media that may be accessed within a computing environment. By way of example, and not limitation, within the computing environment 100 , computer-readable media include memory 120 , storage 140 , communication media, and combinations of any of the above.
Preferred embodiments, as mentioned, include a new packet type that enables requests to be piggybacked with data by means of a ‘piggyback’ packet. More specifically, a piggyback packet may be described with reference to FIG. 2 . In bidirectional real-time traffic, each user may both send and receive data. To this end, a piggyback packet may comprise both data and requests. More specifically, a typical piggyback packet is depicted in FIG. 2 . The piggyback packet 202 may comprise a content object 204 and a request object 212 . The content object 204 of the piggyback packet may additionally include a content name 206 that may identify the nature of the content, as in 204 , an authentication field 208 whereby the identity of the sender or publisher is verifiable or, as in some embodiments, whereby the integrity of the packet is verifiable, and the substantive data or information received or intended to be sent, as in 210 . The piggyback packet 202 may also contain a request object 212 which contains the name of the request 214 . In a piggyback packet, the request object and the content object may be loosely coupled, that is, the content object and the request object may be separable from each other so the piggyback packet may be reconstituted by the receiver node into component data and request packets.
Present embodiments may include processing steps at a client side, that is, at a sender or receiver node communicably coupled with another client that sends or receives one or more piggyback packets over the course of a session. Additional embodiments may include processing steps at a router side, where the router node is involved in the transfer of one or more piggyback packets between the client nodes.
Referring now to FIG. 3 , an initial step 302 in an implementation at a client side is the receipt of one or more requests for data from a remote node or client application, where a client application is a software program or process running on the client device that may optionally provide a user interface by means of which a user may initiate or manage communications with a remote client. In an information centric network in which the embodiments disclosed are implemented, a request to access specific data is sent, by the consumer or sender node, as a request packet. A response to the requested data may be transmitted by the receiver node by means of a data packet. Once the communications session has been initiated, as indicated by the receipt of requests in accordance with 302 , then, as in a step 304 , the client device may switch to a piggyback session.
More specifically, the initiation of a piggyback session may be preceded by the exchange of request packets by participants in the communications session. Each participant, where a participant is a client device running a client application connected to the network, may respond with a data packet on receipt of a regular request packet. When a participant receives a data packet over the network in response to a pending or previously sent request, the participant may switch to a piggyback ‘mode’. In a piggyback mode, in response to a subsequent request or piggyback packet received by the participant, a piggyback packet may be sent in place of a regular data packet, if the participant has both content to send and a request for content from the far-end. If a data packet is received and the participant requires data, a request packet may be sent to the one or more other participants in the communications session. The response of a participant to the receipt of a piggyback packet, a request packet, or a data packet is additionally detailed in FIG. 7 .
Referring now to FIGS. 4 a and 4 b , sending as well as processing piggyback packets involves one or more processing steps. More specifically, a participant in a piggyback mode may additionally comprise a timer and an event handler process, where the event handler process running at the participant may be configured to catch one or more events. Events defined may include an internal timeout event, a request for data from the client application, a request to send data by the client application, a request for data from another participant in the communications session, receipt of data from another participant and the receipt of a piggyback packet from another participant.
Specifically, as in the block 402 of FIG. 4 a , if a request for content is received from a remote participant or a running client application, the request is first mapped to content to be sent. In a first instance, if the request originates from a remote participant and the requested content is available to be sent, then any extant requests for data required from the remote participant and the content to be sent are embedded in a piggyback packet and sent to the remote participant, as in 404 . In some embodiments, if the mapping returns no content at the participant in response to the request from the far end and no corresponding request for data from the remote participant exists, the received request is buffered in a memory at the client device. If the content exists but there is no request for data from a remote participant, the content is also buffered.
In a second instance, if the request for content originates from a client application on the participant, then extant content that maps to a content request from a remote participant is embedded with the request for content in a piggyback packet, and sent to the remote participant, as in 404 . If no such content exists, the request for content is buffered. Also, if there is no pending request for content from a remote participant, the request for content by the client application is buffered at the client device. In some embodiments, if there is content to be sent to a remote node and no content request from the client application is received, the content is buffered.
Referring now to FIG. 4 b , on receiving a piggyback packet, as in 406 , the piggyback packet received may be split into request data and content data, as in the subsequent block 408 , and the content so obtained sent to the client application, as in 410 . The event handler process may be defined by the step of setting one or more events, as in 412 .
A client stack at the participant whereby the initialization and processing of events in a piggyback session is performed, in accordance with some embodiments, is further detailed by means of FIG. 6 . FIG. 6 illustrates the passage of content and requests between a client application 602 and a client stack hosting buffers for requests to be sent 604 , requests received 614 and content to be sent 606 . The buffers may be computer readable memory, for instance. Incoming packets from remote participant are received, their contents are transmitted to the application and requests queued for processing by a receiving module 610 . Packets may be sent to a remote participant by means of a network send module, as in 608 . Sent packets may include piggyback packets, in accordance with some embodiments. Timing events, as in 612 , include an expiry time associated with a request packet or a data packet and a piggyback ‘fallback’ time.
More specifically, when the application 602 sends request and content to the client stack in a piggyback session, the application may specify a maximum time for which the request and content may be stored in the request or content buffers. The time specified, which is the expiry time associated with the request or content, may be smaller than the lifetime of the request or content. The piggyback fall-back time is selected as the minimum of the expiry time of a request and the content.
If a client stack receives both request and content from the application, as well as a request for content from a remote participant, a piggyback packet may be sent in response. In instances where these conditions do not exist, the two timing events may form the basis of decisions at the client stack. More specifically, if the client stack has stored content from the application 602 and has not received a request for content from the application, the piggyback fall-back time may be checked. If the fall-back time exceeds an expiry time associated with a received request from a remote participant, then the stored content may be sent as a normal data packet without waiting to create a piggyback packet with a request from the application 602 .
In another instance, the client stack may have received a request from the application 602 but not yet received either or both of content to send and a request for content from a remote participant. If so, no action may be taken until the piggyback fall-back time. If, by that time, both the remote request and content are received, a piggyback packet may be created and transmitted. If not, only a request packet may be sent to the remote participant.
Aspects of the present invention including processing steps at a router device in order to enable the transfer of piggyback packets across a network. Referring now to FIG. 5 , an initial step in the optimization of bi-directional communications at a router device is the validation of incoming packets, as in 502 . Validation may include checking the validity of the piggyback packet as well as verifying its authenticity. Validity of the packet is done by verifying if the packet structure complies with that of a piggyback packet as depicted in FIG. 2 . Authenticity of the source from which the packet is received is done by checking the authentication field in the packet. Additionally, on receiving a piggyback packet, the router device may confirm that the packet is not a duplicate of a previously received packet. The purpose of such verification may be to forestall flooding of the network with duplicate packets by a malicious router node, for instance. The validation may be performed on the basis of a comparison of the authentication field in the piggyback packet with the authentication fields of received packets. In some preferred embodiments, a nonce field containing a unique nonce may be embedded in the authentication field prior to dissemination by the sender. If a duplicate is detected, the packet is dropped. If the received packet is not a duplicate, prefix based matching of the piggyback name, that is, the content name as in 206 of FIG. 2 , is performed with all pending requests in the router device. The pending requests may be stored in a memory at the router device. If no pending requests match the incoming piggyback packet, the incoming packet is dropped.
If more than one pending request matches, only the closest match is considered. Then, as in 504 , a request entry is created at the router for the request embedded in the piggyback packet. Then, as in 506 , one or more overlapping router interfaces for forwarding the data and request in the piggyback packet to a remote client device are determined. This is done by first, checking the request entry corresponding to the content field in the piggyback packet to get the list of interfaces through which the content can be forwarded towards the remote participant and then matching the request name with the entries in the router's forwarding table to deduce the interfaces through which the request can be forwarded. Overlapping interfaces refer to the list of interfaces that are common in both the list associated with content forwarding and that associated with forwarding the request. One or more of these overlapping interfaces can be selected to forward the piggyback packet towards the remote participant as in 508 . If there are no overlapping interfaces, then the content field of the piggyback packet may be separated from the request field as in 510 and forwarded through the closest matching interface, as in 512 . In some embodiments, the separated request field may additionally be reconstituted as a request packet and forwarded through an interface which is the closest estimated match. If there are no valid interfaces through which the request may be forwarded, it may be discarded.
Embodiments of the invention may incorporate mechanisms for handling packet drop in the network. In a communications session, a packet drop may be caused by any of a variety of reasons, including, for example, loss of network connectivity, malicious router nodes, and congestion. A piggyback session may handle packet drop instances by implementing an associated ‘timeout’ with request packets transmitted in the session. Since communications may be conducted in real-time, the timeout specified in a piggyback sessions may be small enough to recover lost data before the data turns stale. Some embodiments may incorporate methods to handle such timeouts by switching out of the piggyback session and reverting to sending and receiving normal request and data packets. Other embodiments may incorporate mechanisms that detect when the network conditions improve and automatically switch back the piggyback session, thus re-starting piggyback packet exchanges.
Some embodiments may incorporate pipelining in a piggyback session. Pipelines may be implemented by buffering incoming packets into a processor readable memory at each participant. Before the participant enters a piggyback session with a remote participant, a number of request packets equal to a desired pipeline size may be sent thereto. Subsequently, the participant may then receive a number of piggyback packets equal to the number of request packets transmitted. If the participant then receives a request packet in the piggyback session, the number and size of un-serviced pending requests is checked. If the pending requests match the size of the pipeline, the participant may respond with a regular data packet in lieu of a piggyback packet otherwise. If a data packet is received in the piggyback session, the pending interests and pipeline are similarly checked. If the pipeline size has been exceeded, no response may be sent. Otherwise, the participant may reply to the data packet with a regular request packet.
The present description includes the best presently-contemplated method for carrying out the present invention. Various modifications to the embodiment will be readily apparent to those skilled in the art and some features of the present invention may be used without the corresponding use of other features. Accordingly, the present invention is not intended to be limited to the embodiments shown but is to be accorded the widest scope consistent with the principles and features described herein.
As will be appreciated by those of ordinary skill in the art, the aforementioned example, demonstrations, and method steps may be implemented by suitable code on a processor base system, such as general purpose or special purpose computer. It should also be noted that different implementations of the present technique may perform some or all the steps described herein in different orders or substantially concurrently, that is, in parallel. Furthermore, the functions may be implemented in a variety of programming languages. Such code, as will be appreciated by those of ordinary skilled in the art, may be stored or adapted for storage in one or more tangible machine readable media, such as on memory chips, local or remote hard disks, optical disks or other media, which may be accessed by a processor based system to execute the stored code. | Embodiments describe enhancing bi-directional communication in an information centric computer network through a piggyback session, which comprises mapping requests for data received to content, sending at least one piggyback packet to a remote node, wherein a piggyback packet is a data packet comprising a request field and a content field, receiving at least one piggyback packet from the remote node, and processing the piggyback packets. Processing may comprise splitting the request field and the content field in at least one received piggyback packet, sending the content extracted from the received piggyback packet to a client application running on the computing apparatus and setting one or more events to trigger the processing of at least one piggyback packet. Additional embodiments describe the structure of a piggyback packet and the management of a piggyback session at a router device by validating incoming piggyback packets and determining a recipient accordingly. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a garage doorway guard and more particularly pertains to a new garage doorway screen apparatus for allowing fresh air into a garage without allowing pests such as insects and mice into the garage.
2. Description of the Prior Art
The use of a garage doorway guard is known in the prior art. More specifically, a garage doorway guard heretofore devised and utilized are known to consist basically of familiar, expected and obvious structural configurations, notwithstanding the myriad of designs encompassed by the crowded prior art which have been developed for the fulfillment of countless objectives and requirements.
Known prior art includes U.S. Pat. Nos. 5,904,199; 4,378,043; 5,611,382; 4,231,412; 598,256; 4,673,019; and U.S. Pat. No. Des. 374,487.
While these devices fulfill their respective, particular objectives and requirements, the aforementioned patents do not disclose a new garage doorway screen apparatus. The inventive device includes a screen assembly including at least one screen support member and also including at least one screen member being attached to the at least one screen support member with the screen assembly being adapted to be securely and removably disposed in a garage doorway.
In these respects, the garage doorway screen apparatus according to the present invention substantially departs from the conventional concepts and designs of the prior art, and in so doing provides an apparatus primarily developed for the purpose of allowing fresh air into a garage without allowing pests such as insects and mice into the garage.
SUMMARY OF THE INVENTION
In view of the foregoing disadvantages inherent in the known types of garage doorway guard now present in the prior art, the present invention provides a new garage doorway screen apparatus construction wherein the same can be utilized for allowing fresh air into a garage without allowing pests such as insects and mice into the garage.
The general purpose of the present invention, which will be described subsequently in greater detail, is to provide a new garage doorway screen apparatus which has many of the advantages of the garage doorway guard mentioned heretofore and many novel features that result in a new garage doorway screen apparatus which is not anticipated, rendered obvious, suggested, or even implied by any of the prior art garage doorway guard, either alone or in any combination thereof.
To attain this, the present invention generally comprises a screen assembly including at least one screen support member and also including at least one screen member being attached to the at least one screen support member with the screen assembly being adapted to be securely and removably disposed in a garage doorway.
There has thus been outlined, rather broadly, the more important features of the invention in order that the detailed description thereof that follows may be better understood, and in order that the present contribution to the art may be better appreciated. There are additional features of the invention that will be described hereinafter and which will form the subject matter of the claims appended hereto.
In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting.
As such, those skilled in the art will appreciate that the conception, upon which this disclosure is based, may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention.
Further, the purpose of the foregoing abstract is to enable the U.S. Patent and Trademark Office and the public generally, and especially the scientists, engineers and practitioners in the art who are not familiar with patent or legal terms or phraseology, to determine quickly from a cursory inspection the nature and essence of the technical disclosure of the application. The abstract is neither intended to define the invention of the application, which is measured by the claims, nor is it intended to be limiting as to the scope of the invention in any way.
It is therefore an object of the present invention to provide a new garage doorway screen apparatus which has many of the advantages of the garage doorway guard mentioned heretofore and many novel features that result in a new garage doorway screen apparatus which is not anticipated, rendered obvious, suggested, or even implied by any of the prior art garage doorway guard, either alone or in any combination thereof.
It is another object of the present invention to provide a new garage doorway screen apparatus which may be easily and efficiently manufactured and marketed.
It is a further object of the present invention to provide a new garage doorway screen apparatus which is of a durable and reliable construction.
An even further object of the present invention is to provide a new garage doorway screen apparatus which is susceptible of a low cost of manufacture with regard to both materials and labor, and which accordingly is then susceptible of low prices of sale to the consuming public, thereby making such garage doorway screen apparatus economically available to the buying public.
Still yet another object of the present invention is to provide a new garage doorway screen apparatus which provides in the apparatuses and methods of the prior art some of the advantages thereof, while simultaneously overcoming some of the disadvantages normally associated therewith.
Still another object of the present invention is to provide a new garage doorway screen apparatus for allowing fresh air into a garage without allowing pests such as insects and mice into the garage.
Yet another object of the present invention is to provide a new garage doorway screen apparatus which includes a screen assembly including at least one screen support member and also including at least one screen member being attached to the at least one screen support member with the screen assembly being adapted to be securely and removably disposed in a garage doorway.
Still yet another object of the present invention is to provide a new garage doorway screen apparatus that is easy and convenient to set up in one's garage doorway.
Even still another object of the present invention is to provide a new garage doorway screen apparatus that allows offensive odors and dangerous fumes to escape the garage.
These together with other objects of the invention, along with the various features of novelty which characterize the invention, are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and the specific objects attained by its uses, reference should be made to the accompanying drawings and descriptive matter in which there are illustrated preferred embodiments of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be better understood and objects other than those set forth above will become apparent when consideration is given to the following detailed description thereof. Such description makes reference to the annexed drawings wherein:
FIG. 1 is a perspective view of a first embodiment of a new garage doorway screen apparatus according to the present invention.
FIG. 2 is a perspective view of a second embodiment of the present invention.
FIG. 3 is a perspective view of the first embodiment of the present invention shown in use.
FIG. 4 is a perspective view of a third embodiment of the present invention.
FIG. 5 is a cross-sectional view of the first embodiment of the present invention.
FIG. 6 is a cross-sectional view of the third embodiment of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
With reference now to the drawings, and in particular to FIGS. 1 through 6 thereof, a new garage doorway screen apparatus embodying the principles and concepts of the present invention and generally designated by the reference numeral 10 will be described.
As best illustrated in FIGS. 1 through 6, the garage doorway screen apparatus 10 generally comprises a screen assembly including at least one screen support member 11 , 14 , 30 and also including at least one screen member 19 , 20 , 29 being conventionally attached to the at least one screen support member 11 , 14 , 30 . The screen assembly is adapted to be securely and removably disposed in a garage doorway 34 . As a first and second embodiments, the at least one screen support member 11 , 14 , 30 includes a first frame member 11 and a second frame member 14 being telescopingly attached to the first frame member 11 . The at least one screen member 19 , 20 , 29 includes first screen members 19 being securely and conventionally attached to the first frame member 11 and also includes second screen members 20 being securely and conventionally attached to the second frame member 14 . The first frame member 11 includes an inverted U-shaped upper elongate cross member 12 and also includes a U-shaped lower elongate cross member 13 . The second frame member 14 includes an inverted U-shaped upper elongate cross member 15 and also includes a U-shaped lower elongate cross member 16 . The upper elongate cross member 115 of the second frame member 14 is slidably received in and extended from the upper elongate cross member 12 of the first frame member 11 . The lower elongate cross member 16 of the second frame member 14 is slidably received in and extended from the lower elongate cross member 13 of the first frame member 11 . For the second embodiment, the second frame member 14 further includes an elongate intermediate cross member 17 having a plurality of teeth 18 being spaced along and disposed in a top edge thereof. The screen assembly further includes a latch support member 21 being securely and conventionally attached to the first frame member 11 intermediate of the upper and lower elongate cross members 12 , 13 , and also includes an elongate latch member 22 being pivotally and conventionally attached to the latch support member 21 and having a plurality of teeth 23 being spaced along and disposed in a bottom edge thereof. The elongate latch member 22 is fastenable to the elongate intermediate cross member 17 to lock the second frame member 14 at a desired position relative to the first frame member 11 with the teeth 23 of the elongate latch member 22 being interlockably connected to the teeth 18 of the elongate intermediate cross member 17 .
As a third embodiment, the screen assembly further includes an elongate housing member 24 having a longitudinal slot 27 being disposed through a top corner 25 thereof and extending a length of the elongate housing member 24 , and also includes a spindle 28 being rotatably and conventionally disposed in the elongate housing member 24 , and further includes a weighted base member 35 being securely and conventionally attached to a bottom wall 26 of the elongate housing member 24 , and also includes sinusoidal-shaped hook members 32 being removably and conventionally connected to the at least one screen support member 30 and being adapted to hook to a garage door 33 . The at least one screen member 29 includes a screen member 29 being carried by the spindle 28 and being extendable through the longitudinal slot 27 of the elongate housing member 24 . The at least one screen support member 30 includes a support bar 30 being securely and conventionally attached to a top edge of the screen member 29 and having holes 31 disposed therethrough and being adapted to receive the sinusoidal-shaped hook members 32 .
In use, the user raises the garage door and places the garage doorway screen apparatus 10 in the doorway 34 of the garage such that the doorway screen apparatus 10 closes the space between the garage door 33 and the floor of the garage.
As to a further discussion of the manner of usage and operation of the present invention, the same should be apparent from the above description. Accordingly, no further discussion relating to the manner of usage and operation will be provided.
With respect to the above description then, it is to be realized that the optimum dimensional relationships for the parts of the invention, to include variations in size, materials, shape, form, function and manner of operation, assembly and use, are deemed readily apparent and obvious to one skilled in the art, and all equivalent relationships to those illustrated in the drawings and described in the specification are intended to be encompassed by the present invention.
Therefore, the foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention. | A garage doorway screen apparatus for allowing fresh air into a garage without allowing pests such as insects and mice into the garage. The garage doorway screen apparatus includes a screen assembly including at least one screen support member and also including at least one screen member being attached to the at least one screen support member with the screen assembly being adapted to be securely and removably disposed in a garage doorway. | 4 |
TECHNICAL FIELD
The present invention relates to shaft furnaces and more particularly to devices for charging shaft furnaces.
BACKGROUND OF THE INVENTION
U.S. Pat. No. 3,880,302, describes an apparatus for charging a shaft furnace which comprises two locks placed next to one another and operating alternately. This known charging installation is supported by a relatively large framework which is itself carried by a square tower installed round the furnace. The distributor chute is suspended on the diametrically opposed axles of two drive housings revolving round the vertical axis under the action of the first running ring. Each of these housings is connected to the second running ring by means of several pinions and gears, in order to change the inclination of the chute relative to the axis of the furnace. The distributor chute, the inner lining of which has to be regularly renewed, can be replaced by means of a handling device of the type described in the U.S. Pat. No. 4,729,549. According to this patent, the chute is extracted laterally through an orifice made in the upper conical part of the furnace wall.
This charging installation and the mechanism for driving the chute have proved especially effective and advantageous for use on new blast furnaces or for major repairs and since the initial design of this charging installation it has equipped many blast furnaces.
Unfortunately, it has been impossible for this installation of very high performance on blast furnaces of large size, to be adapted with similar success to blast furnaces of smaller size, especially those without a square tower. In this type of furnace, the charging installation and the work platform surrounding it are supported directly by the all of the furnace. Unless reinforcements are provided beforehand as a result of major costly conversions, it is therefore impossible to dismount the distributor chute in the way proposed in the above mentioned document, since an orifice cannot be made in the furnace wall and in the work platform to avoid reducing their stability and resistance.
To avoid having to pierce the wall of the furnace in order to dismount the chute, Luxembourg Patent Application No. 87,219 (copending commonly assigned U.S. patent application, Ser. No. 382,517, filed July 19, 1989, now U.S. Pat. No. 4,941,792), proposed to dismount the chute upwards through the casing of its drive mechanism. Despite this solution, there is still the problem that the installation is supported by the furnace wall. In fact, it is well known that the furnace wall experiences thermal expansion movements and this consequently has an effect on the casing of the drive mechanism of the chute, this therefore being exposed to risks of deformation. Now the drive mechanism known from U.S. Pat. No. 3,880,302, comprising a complex system of gears and pinions, especially in the region of the two rotary housings generating the pivoting of the chute, does not tolerate deformations of this extent.
Moreover, when a conventional bell-type charging device of an existing furnace is to be replaced by a modern charging apparatus with a rotary distributor chute, the problem of availability of space arises. In fact, the new apparatus has to be arranged between the supporting collar of the lower bell and the installation for raising the charging material, this usually being a skip transporter. Unfortunately, this available space is often very limited and it is therefore difficult to provide a charging installation of the above described type in it.
SUMMARY OF THE INVENTION
The object of the present invention is to provide a new installation for charging a shaft furnace, which is equally suitable for blast furnaces of small and medium size, particularly as a replacement of a conventional bell-type charging installation.
To achieve this object, the present invention proposes an installation of the type described in the precharacterizing clause, which is characterized essentially in that the distributor chute is supported pivotably between and by two horizontal crossmembers extending in parallel on either side of the chute, on the inside of the said first ring and fastened directly to the latter, and in that the chute is connected to the said second ring by means of an articulated linkage.
Because the two running rings are mounted coaxially one above the other and the chute is suspended between these two rings, the overall height of the drive mechanism is reduced virtually to the sum of the thickness of these two rings. This decrease in total height of the drive mechanism consequently correspondingly reduces the total height of the charging installation and makes it easier to arrange it in the available space between the furnace head and the transporters for the charging material.
Moreover, the small height of the mechanism for driving the chute makes it easier to dismount the latter upwards through the valve cage.
The angular adjustment of the distributor chute is obtained by means of the linkage under the action of a relative movement between the two running rings. Such a linkage withstands deformations of the casing of the drive mechanism better than the known transmissions with gears and pinions.
The chute is supported dismountably by two lateral flanges, each possessing a supporting journal seated respectively in a bearing of each of the said crossmembers.
The suspension and orientation of the chute can be obtained by means of two pairs of pins fastened to the outer wall of the chute and engaged by sliding into two corresponding grooves which are provided respectively in the inner faces of each of the flanges and in which the chute is retained as a result of its own weight.
The grooves and pins can be profiled and associated with a locking device, in order to prevent the chute from being disconnected accidentally.
The linkage connecting the chute to the second running ring consists of a first arm integral with one of the flanges, of a second arm integral with the second running ring and of a link articulated on the free ends of each of the said arms.
This new mechanism for driving the chute is especially suitable for an efficient cooling of the most vulnerable parts. In particular, the device can have an annular thermal protection shield fastened underneath the drive means and connected to a cooling-fluid circuit, and cylindrical thermal protection segments fastened to the inside of the first running ring and extending over the height of the two rings, at least over most of the circumference.
Furthermore, each of the running rings can be associated with a cylindrical thermal protection screen connected to a cooling-fluid circuit.
The two crossmembers for the suspension of the chute ca likewise be cooled. For this purpose, each of these can be designed in the form of a hollow box integrated into a circuit for cooling by evaporation, which comprises two circular conduit segments fastened to the first running ring and subjected to the action of a cooling means. The latter can consist of a ring of outer radial blades on the said conduit and a second ring of inner radial blades fastened round the said first ring on the inner wall of the casing in which the running rings are mounted.
According to a first embodiment, the lower sealing flap of the lock is mounted in valve cage forming a unit with the lock and the casing containing the drive means of the chute, this unit being carried by an annular support closing the upper part of the furnace.
According to a second embodiment, the lock is supported by the furnace head by means of load cells and an intermediate framework, while it is connected by means of compensators to an underlying valve cage which forms a unit with the casing containing the drive means.
The above-discussed and other features and advantages of the present invention will be appreciated and understood from the following detailed description and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
Referring now to the drawings, wherein like elements are numbered alike in the several FIGURES:
FIG. 1 is a diagrammatic view in vertical section of a first embodiment of a charging installation in accordance with the present invention;
FIG. 2 is a view, similar to that of FIG. 1, of a second embodiment of a charging installation in accordance with the present invention;
FIG. 3 is a vertical section the details of the mechanism for driving the chute;
FIG. 4 is a view similar to that of FIG. 3 in a sectional plane perpendicular relative to this;
FIG. 5 is a plan view of the representation of FIG. 4;
FIG. 6 is an enlarged view of part of FIG. 3, with details of the suspension and fastening of the chute;
FIG. 7 shows the same details as FIG. 6 by means of an enlarged view of part of FIG. 4, and
FIG. 8 shows in vertical cross section the details of the cooling of the running rings;
FIG. 9 is a horizontal section in the sectional plane IX--IX of FIG. 8;
FIGS. 10 and 11 show diagramatically an embodiment of a system for cooling the suspension crossmembers of the chute, in vertical section along the respective sectional planes X--X and XI--XI of FIG. 12; and
FIG. 12 shows diagramatically in horizontal section the system for cooling the suspension cross members in accordance with the present invention.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 illustrates the head of a blast furnace 10, in which a conventional bell-type charging installation has been replaced by a first embodiment of a charging installation according to the present invention. The reference 12 denotes a supporting collar in the form of a hollow dish, serving to match to the new installation the annular edge which before served as a support for the lower bell and which now serves as a support for the entire charging installation.
The charging installation consists, from the bottom upwards of a casing 14 fastened in the recess of the support 12 and containing the mechanism for driving a rotary distributor chute 16 of variable angle of adjustment of a valve cage 18 of a central charging lock 20 and of an installation for raising the charging material consisting in this particular case of two skip transporters 22 and 24. These two skip transporters 22 and 24 formed part of the prior charging installation according to the present invention must be designed to be arranged between these skip transporters 22, 24 and the support collar 12.
The charging lock 20 communicating alternately with the atmosphere and the interior of th furnace is equipped with one or, in the example shown, with two upper sealing flaps 26 and 28 and with a lower sealing flap 30 which is located in the valve cage 18. The flow of charging materials from the lock 20 is adjusted by means of a metering valve 32 which acts symmetrically about the vertical axis 0 and which is known per se. This valve 32 is mounted on the lower part of the wall of the lock 20.
One of the particular features of the charging installation according to the present invention is that it is designed to allow the chute 16 to be dismounted in an oblique upward direction, this being illustrated by the representation of the chute in the form of broken lines. For this purpose, both the mechanism for driving the chute and the valve cage 18 must be designed to allow the passage of the chute 16. To achieve this, the casing 14 of the drive mechanism must be very low, whereas the valve cage 18 must be relatively high. Furthermore, the valve cage 18 possesses a removable cover 34, in order to allow the extraction of the chute 16, and where appropriate, the inspection of the mechanism for driving the chute.
The embodiment of FIG. 1 is characterized in that the lock 20, the valve cage 18 and the casing 14 to form a constructional unit which is supported completely by the dish 12.
The embodiment of FIG. 2 differs from the embodiment of FIG. 1 only in its suspension. In the embodiment of FIG. 2, in fact, the lock 20 is supported by a circular or square girder 36, itself carried by several pillars 38 bearing on the outer edge of the dish 12. The lock 20 can be carried directly by the girder 36 or preferably indirectly be means of load cells 42 which make it possible to monitor the contents of the lock 20. To make it possible to weight this lock 20, it is independent of the valve cage 18, to which it is connected only by a compensator 40 ensuring freedom of vertical movement of the lock, and at the same time, sealing relative to the outside.
In contrast, as in FIG. 1, the valve cage 18 remains fixed to the casing 14, with which it forms a unit carried by the support 12.
FIG. 2A shows an advantageous embodiment of the seat of the lower sealing flap 30 for the purpose of making it easier to dismount it. The annular seat designated by 31, which can be hollow for the circulation of a cooling fluid, is wedged between bevelled orifice in the upper wall of the cage 18 and a sealing collar 33 equipped with upper and lower O-ring gaskets. The reference 35 denotes a bracket to which the compensator 40 is welded. The clamping of the bracket 35, collar 33 and seat 31 can be carried out by means of a set of bolts which are symbolized by the reference 37 and which it is sufficient to slacken and remove in order to release and remove the collar 33 and seat 31 laterally. It is advantageous to design the compensator 40 in such a way that it is tensioned when the bolts 37 are tightened. The slackening of the bolts 37 thus releases the compensator 40 and the loosening of the latter lifts the bracket 35 so as to release the collar 33 and the seat 31.
It should be noted that, since it is not possible to weigh the lock 20 in the embodiment of FIG. 1, the content of the lock 20 can be checked by other means, such as level probes, a check of the flow time, etc.
The mechanism for driving the chute 16 will now be described in more detail by reference to FIGS. 3 to 5. The essential characteristics of this drive mechanism are that it is especially suitable for a low construction, an efficient cooling of its components, easy dismounting of the chute upwards through the valve cage and the use of only a few pinions and gears, consequently tolerating the small deformations caused by the support of the installation and movements of the furnace.
The drive mechanism essentially comprises a first and a second running assembly which consist respectively of two collars 46, 48 fixed to the wall of the casing 14 and of two toothed running rings 50, 52 revolving round the collars 46 and 48 by the agency of known rolling means, such as balls or rollers. The two toothed rings 50, 52 are actuated independently by means of pinions which are not shown and which form part of a drive system making it possible either to rotate the two rings 50, 52 synchronously or to decelerate or accelerate the ring 50 in relation to the ring 52. Such a drive system can consist, for example, of a gear system of the planetary type, as described in U.S. Pat. Nos. 3,880,301 and 4,273,492, the disclosures of which are incorporated herein by reference.
As shown in FIGS. 3 and 4, the two running rings 50, 52 have a U-shaped cross-section and are arranged one above the other symmetrically in relation to a horizontal mid-plane. These running rings 50, 52 by means of the hollow portion of their cross-section, are respectively suspended on and carried by the stationary bearing collars 46, 48 the inner branches of their cross-section 50a, 52a forming coaxial cylindrical collars in alignment with one another.
As shown in FIGS. 3 and 4, two parallel horizontal crossmembers 54, 56 are welded to the inside of the lower running ring 52 at a sufficient distance from the central axis 0 to allow suspension of the chute 16. This chute 16 is suspended by means of two lateral flanges 58, 60, each of these flanges being equipped with an outer journal 62, 64 these being supported pivotably in bearings provided in each of the crossmembers 54, 56. The inclination f the chute 16 relative to the vertical axis 0 (see FIG. 4) can therefore be changed as a result of the pivoting of the journals 62, 64 about their horizontal axle for suspension in the crossmembers 54, 56. The inclination of the chute 16 relative to the vertical inclination of the chute 16 relative to the vertical axis 0 is adjusted under the action of the running ring 50. For this purpose, one of the suspension flanges of the chute, in this particular case the flange 60, is extended upwards by a control arm 66. Another arm 68 is integral with the running ring 50, and the free ends of each of these arms 66, 68 are connected to one another by means of a link 70, the opposite ends of which are articulated on the ends of each of the arms 66, 68 by means of a universal joint, for example a ball-and-socket joint.
When the two running rings 50, 52 are actuated synchronously at the same angular speed, the distributor chute 16 rotates about the axis 0 at a constant inclination, in order to deposit the charging material in circles. In contrast, if, under the action of the planetary drive mechanism, the running ring 50 executes a relative movement in relation to the speed of the ring 50 as a result of acceleration or a reversal of the direction of rotation, it acts by means of the link 70 on the arm 66 and the suspension flange 60 of the chute 16 in order to change the angle of inclination of the chute 16 relative to the vertical axis 0. FIG. 5 shows two different relative positions of the arm 68, one represented by unbroken lines and the other by broken lines. It will be seen that the relative movement of the ring 50 in relation to the ring 52, necessary for tilting the chute 16 between its maximum inclination and its minimum inclination, is very small. This relative movement corresponds approximately to the two positions shown in FIG. 5, that is to say the maximum angular offset of the ring 50 in relation to the ring 52 is of the order of 30°.
This mechanism for driving the chute, because of its simplicity, is especially suitable for an efficient cooling of the most exposed and most vulnerable elements. Thus, most of the drive mechanism is protected from the direct radiation of the furnace by an annular shield 76 (see FIGS. 8 and 9), the central orifice of which is just large enough to allow the chute 16 to rotate within the limits of its angular inclinations. This shield 76 is stationary and can therefore be equipped with internal cooling coils connected to a circuit for a cooling fluid, for example water. Moreover, it can be equipped, on its lower face, with a refractory lining 77.
In the embodiment illustrated in FIGS. 8 and 9, the cavity in the shield 76 is divided into several, in this particular case 4 segments, each equipped with an inlet 79 and an outlet 81 for a cooling fluid. The inner cavity of the shield possesses radial ribs 83 and 85 defining a serpentine path for the cooling fluid.
Moreover, a series of cylindrical thermal protection segments 78, 80, 82 is fastened to the inside of the ring 52 and extends vertically over the entire height of the two running rings 50, 52, with the exception of the segment 82 which must have a lower cross-section to allow the relative angular movements of the arm 68 for the pivoting of the chute 16. These protective segments which together with the running ring 52 and the chute 16 rotate about the axis 0, protect the running rings from the radiation coming from inside the furnace. This protection is advantageously completed by a cooling of the running rings. For this purpose, an annular cooling chamber 84, 86 (see FIGS. 4 and 8) is fastened on the inside of each of the bearing collars 46 and 48 and penetrates into the hollow cross-section of the running rings 50, 52. These chambers 84, 86 are likewise connected to a circuit for a cooling fluid, for example water. These chambers 84, 86 are preferably divided, in the manner of the shield 76, into several circular sections, each possessing an inlet 85 and an outlet 87 for cooling water and being equipped with partial internal partitions 89 to define the serpentine path of the cooling water.
The system for fastening the chute 16 between the two flanges 58 and 60 will now be described by reference to FIGS. 4 to 7. Each of the flanges 58, 60 has a groove 88 open upwards in the dismounting direction of the chute and widening slightly in this direction, as shown enlarged in FIG. 7, to make it easier to remove the chute. The chute 16 possesses two lateral pins 90, 92 of such design and dimensions as to be capable of sliding into the grooves 88 of each of the flanges 58 and 60 and of being retained at the bottom of these grooves. To prevent the chute 16 from pivoting relative to the flanges 58, 60, the chute has two additional lateral pins 94 and 95 wider than the pins 90 and 92. These pins 94 and 95 are likewise engaged into the grooves 88 of the flanges 58 and 60 when the other pair of pins 90, 92 is at the bottom of these grooves.
To prevent a lateral play of the chute 16 in relation to the flanges 58, 60 the pins on one side preferably the pins 92 and 94, and the groove 88 of the corresponding flange 60 are profiled in a complementary way. As shown in FIG. 6, the pin 92 can have a circular flute 96 of the pin 92. The pin 90 opposite the profiled pin 92 must be straight in order to allow the relative movements arising as a result of thermal expansions.
The chute 16 can therefore be retained in the grooves 88 of these two flanges 56 and 60 by means of its own weight and can be removed from them by sliding after the chute has been inclined in the direction of its removal. To prevent the chute 16 from being disconnected accidentally, for example in contact with the charging material in the furnace, it is possible to associate this fastening system with a locking means. As shown in FIG. 7, the two flanges 58, 60 can be designed so that it is possible to engage in them a gudgeon 98 which blocks the passage of the lower pins 90, 92 when these are located at the bottom of their grooves. In order to dismount the chute, it is therefore necessary to remove the locking gudgeons 98 beforehand.
FIGS. 10 and 12 illustrate an advantageous system for cooling the two crossmembers 54 and 56 and more particularly the bearings in which the suspension journals 62 and 64 of the chute 16 pivot. Since the cooling systems of the two crossmembers 54 and 56 are identical, only that associated with the crossmember 56 will be described. As shown in the FIGURES, the lower part of the crossmember 56 is designed in the form of a hollow box in which a cooling fluid is located. This box communicates by means of two conduits 100, 102, with a chamber 104 which is fastened to the running ring 52 and which extends approximately over the entire length of the crossmember 56. The hollow part of the crossmember 56 is partially filled with a cooling fluid, such as water or preferably a cooling fluid, for example a sodium solution. The outer face of the chamber 104 and the inner face of the wall of the casing 15 have blades 106, 108 directed towards one another.
Under the effect of heat, the fluid contained in the crossmember 56 evaporates. This evaporation temperature must be below the limiting temperature allowing proper functioning of the drive mechanism and can be determined by the pressure in the closed circuit formed by the crossmember 56 and the chamber 104. The evaporated fluid passes into the chamber 104 via the conduit 102. In this chamber 104 which is at a temperature below the evaporation temperature of the fluid because of the large surface of the blades 106 and their rotation opposite the blades 108, the vapor condenses and returns to the crossmember 56 once again in liquid form via the conduit 102.
Automatic cooling of the crossmembers 54 and 56 without external involvement is thus obtained, the excess heat of the crossmembers being dissipated by means of the surface of the ring of blades 106.
To stimulate the circulation of the fluid, it is possible to inject into the space round the running ring 52 a cooled inert gas which can at the same time perform a sealing function by means of counterflow circulation.
While preferred embodiments have been shown and described, various modifications and substitutions may be made thereto without departing from the spirit and scope of the invention. Accordingly, it is to be understood that the present invention has been described by way of illustrations and not limitation. | The present invention relates to an apparatus for charging a shaft furnace. The apparatus includes a rotary and pivoting distributor chute suspended on the head of the furnace, a device for driving this chute, which consists of a first and second running ring designed respectively for rotating the chute about the vertical axis of the furnace and for changing its inclination relative to this axis as a result of a pivoting about its horizontal suspension axis, and a device for actuating the two running rings independently of one another, a central charging lock equipped with upper and lower sealing flaps and with a metering and closing valve for adjusting the flow of material from the lock on to the distributor chute, and a device for filling the lock. | 2 |
TECHNICAL FIELD
[0001] This patent of invention application relates to a device to be used in mechanically enlarge of caisson bases, so that form a semi-spherical cavity at the base of caisson performed.
[0002] Currently, every soil excavating process for carrying out of base for caissons é performed manually, consisting of carrying out the same with a operator going down in the shank of caisson for enlarging the base, which process impose risks to the executor, incurring the possibility of soil landslip.
[0003] In this patent of invention application, the developed process has the purpose to remove the human figure of the process, avoiding burial risks and speeding up the base enlarging process, which is efficient in terms of reduction of execution time in the order of 80% or more.
[0004] Some features of purpose of invention are:
possibility of change in knives, which allows a opening of bases with different diameters; creation of a collector system facilitating the removal of excavated soil, besides take the easy of coupling in consideration.
SUMMARY DESCRIPTION OF INVENTION
[0007] The present invention relates to a device to be used in mechanically enlarge of caisson bases.
[0008] Device for enlarging caisson bases comprises:
an engine shaft; a socket of engine shaft; a fixation pin of engine shaft; a moveable column; a guide ring bound to moveable column; a rotary joint, a stationary column; two side arms and two knives fixed to arms, which are part of soil excavating mechanism; a collector vessel of excavated soil bound to stationary column; and pivotable caps at vessel.
[0018] The device is a mechanism comprising, at upper extremity, the socket of engine shaft of machine carrying out the mechanical excavating of caisson (the fixation of shaft in socket is made through cylindrical pin), being, at the side arms, the knives carrying out the enlarging and, at lower extremity, a collector vessel of excavated soil.
[0019] The engine shaft rotates and presses the device against the bottom of orifice. The side arms of device open and the knives perform the excavation of soil, which is lodge at collector vessel, as the excavation proceeds.
[0020] The collector vessel, at the base of mechanism, is bound to its, through rotary joint, so that, while the mechanism rotates, the collector vessel could not rotate.
[0021] After the end of operation, a collector pan can already rotate, removing the soil from the bottom of caisson which is irregular due to excavation process of shank, providing a compact surface at the base of same.
[0022] To better understanding, the following schematic figures of particular embodiments of invention will be shown, the dimensions and ratios of which are not real necessarily, because the figures has the only purpose for didactically show the preferred applications, the protection scope of which is determined by the scope of appended claims.
BRIEF DESCRIPTION OF DRAWINGS
[0023] This invention will be better understood by means of figures, which illustrate schematically the following:
[0024] FIG. 1 —perspective view of device in general feature;
[0025] FIG. 2 —front view of device during the performance of enlarging of caisson base;
[0026] FIG. 3 —view of device at initial position, about to initiate the enlarging of caisson base;
[0027] FIG. 4 —view of device at final position of enlarging operation;
[0028] FIG. 5 —view of device already out of caisson, with pivotable caps at position for eliminating excavated soil;
[0029] FIG. 6 —view of shank of accomplished caisson ( 6 a ) and view of caisson base enlarged by device ( 6 b );
[0030] FIG. 7 —view of stationary and moveable columns, separated by rotary joint, in details; and
[0031] FIG. 8 —schematic view of fixation of knife in the side arm.
DETAILED DESCRIPTION OF INVENTION
[0032] According to FIG. 1 , it is possible to note the general feature of device for enlarging caissons, said device comprising, at upper extremity thereof, a socket ( 11 ) of engine shaft ( 1 ), a guide ring ( 2 ), a soil excavating mechanism ( 3 ), and a collector vessel for excavated soil ( 4 ).
[0033] Said soil excavating mechanism ( 3 ) and collector vessel of excavated soil ( 4 ) has cylindrical shape, which fits to diameter of caisson to be enlarged.
[0034] FIG. 2 shows the device in details, during the performance phase of enlarging a caisson base, wherein said device comprises, at upper extremity thereof, the socket ( 11 ) of engine shaft ( 1 ) of machine carrying out the mechanical excavating of caisson, wherein a fixation of shaft ( 1 ) in the socket ( 11 ) is made through a cylindrical fixation pin ( 12 ), said device comprises, at side arms ( 6 ) thereof, knives ( 7 ) which perform the enlarging of caisson base, and said device further comprises a collector vessel ( 4 ) of excavated soil at lower extremity thereof.
[0035] During the enlargement performance, engine shaft ( 1 ) rotates and presses the device against the bottom of caisson, thus, side arms ( 6 ) open and knives ( 7 ), fixed to arms ( 6 ), perform excavation of soil, which will be lodge in the collector vessel ( 4 ). Said collector vessel ( 4 ) is bound to said mechanism ( 3 ), at base thereof, through a rotary joint ( 8 ), such that, while mechanism ( 3 ) rotates, the vessel ( 4 ) could not rotate.
[0036] Said side arms ( 6 ) are fixed in the excavating mechanism ( 3 ) through horizontal bars ( 62 ) and pivotable bars ( 61 ), moving in accordance with motion of moveable column ( 5 ), as said moveable column ( 5 ) is pressed against the caisson, thus allowing the arms ( 6 ) to leave of initial position thereof, and moving to the final position of enlarging process. Said bars ( 61 , 62 ) and arms ( 6 ) are hinged through pins ( 63 ).
[0037] FIGS. 3 and 4 show, respectively, device at the initial position, about to initiate the enlarging operation of caisson base, and the device at the final position of operation, wherein the soil excavated by knives ( 7 ) is lodged in the collector vessel ( 4 ). Device is shown at FIG. 5 , already out of caisson after operation, with pivotable caps ( 41 ) at position for eliminating excavated soil, arranged at lower portion of collector vessel ( 4 ). Said pivotable caps ( 41 ) have a semi-circular shape, matching with collector vessel ( 4 ).
[0038] FIGS. 6 a and 6 b show the shank of accomplished caisson, before and after the base enlarging by said device, respectively.
[0039] In accordance with FIG. 7 , it can be seen the columns, called stationary ( 9 ) and moveable ( 5 ), separated by rotary joint ( 8 ) of device for enlarging.
[0040] Said stationary ( 9 ) and moveable ( 5 ) columns have cylindrical shape, and further, said moveable column ( 5 ), according to motion thereof, works at the device like a shaft.
[0041] At the beginning of enlarging operation, pin ( 81 ) crosses the lock ( 82 ), and lateral portion ( 85 ) of rotary joint ( 8 ), such that two columns stand alone. This allows the rotate of collector pan ( 4 ), removing the soil from the bottom of caisson, which is irregular due to excavation process of shank, and providing a compact surface at the base of caisson.
[0042] A lower portion ( 84 ) is a stand-alone stationary column ( 9 ), and together with upper portion ( 83 ), through bolt ( 87 ), they make a coupling of rotary joint ( 8 ), which allows motion at the same longitudinal axis of engine shaft ( 1 ), and moveable column ( 5 ) with the stationary column ( 9 ). This alignment is obtained in operation both with and without the lock pin ( 81 ).
[0043] Rotary joint ( 8 ) further comprises abutment joints ( 86 ) disc-shaped, to eliminate the friction between metallic parts in the excavation operation of soil, wherein, at this moment, only the moveable column ( 5 ) rotates.
[0044] At following step, lock pin ( 81 ) is removed, and only the moveable column ( 5 ) rotates, causing the knives ( 7 ) starts the soil removal process.
[0045] Said knives ( 7 ) are fixed to side arms ( 6 ) through three bolts ( 64 ), as shown at FIG. 8 , providing a risk-proof fixation.
[0046] In addition, device allows utilization of knives with different sizes, so as to provide different diameters of base for the same diameter as the shank of caisson. Said knives ( 7 ) have an L-shape, and at upper portions thereof, a portion of knife ( 71 ) is tilted, so as remove the soil easier.
[0047] The scope of this patent of invention, therefore, should not be limited to illustrated applications, but, instead, only to terms defined at claims and equivalents thereof. | The present invention relates to a device used to mechanically enlarge the base de caissons, so as to form a semi-spherical cavity in the base de the caisson formed, in which said device includes a socket in the upper extremity thereof for the engine shaft, a guide ring, a soil excavating mechanism and a recipient for collecting the excavated soil. | 4 |
FIELD OF THE INVENTION
This invention relates to cured perfluoroelastomer articles, and in particular to cured perfluoroelastomer articles comprising more than 50 parts by weight barium sulfate per hundred parts by weight perfluoroelastomer.
BACKGROUND OF THE INVENTION
Perfluoroelastomer articles have achieved outstanding commercial success and are used in a wide variety of applications in which severe environments are encountered, in particular those end uses where exposure to high temperatures and aggressive chemicals occurs. For example, these articles are often used in seals for aircraft engines, in oil-well drilling devices, and in sealing elements for industrial equipment that operates at high temperatures.
The outstanding properties of perfluoroelastomer articles are largely attributable to the stability and inertness of the copolymerized perfluorinated monomer units that make up the major portion of the polymer backbones in these articles. Such monomers include tetrafluoroethylene and perfluoro(alkyl vinyl) ethers. In order to develop elastomeric properties fully, perfluoroelastomer polymers are cured, i.e. crosslinked. To this end, a small percentage of cure site monomer is copolymerized with the perfluorinated monomer units. Cure site monomers containing at least one nitrile group, for example perfluoro-8-cyano-5-methyl-3,6-dioxa-1-octene, are especially preferred. Such compositions are described in U.S. Pat. Nos. 4,281,092; 4,394,489; 5,789,489; and 5,789,509.
Perfluoroelastomer articles that are employed in high temperature environments (i.e. >250° C.) can break or split and may also become sticky.
It would be an improvement to have cured perfluoroelastomer elastomer articles that are resistant to breaking or splitting and to becoming sticky at high temperature.
SUMMARY OF THE INVENTION
It has been surprisingly discovered that cured perfluoroelastomer articles that contain a high level of BaSO 4 are resistant to splitting and becoming sticky at high temperature, while maintaining good compression set.
Accordingly, an aspect of the present invention is directed to a cured perfluoroelastomer article comprising
A) a perfluoroelastomer comprising copolymerized units of i) 15 to 60 mole percent perfluoro(alkyl vinyl ether), ii) 0.1 to 5 mole percent of a cure site monomer and the remaining copolymerized units being of iii) tetrafluoroethylene so that total mole percent is 100; and B) greater than 50 parts by weight, per hundred parts by weight perfluoroelastomer, of BaSO 4 .
DETAILED DESCRIPTION OF THE INVENTION
The perfluoroelastomers employed in the cured articles of the present invention are capable of undergoing crosslinking reactions (i.e. curing) with any of the common curatives for perfluoroelastomers such as, but not limited to organotin (U.S. Pat. No. 5,789,489), bis(aminophenols) such as diaminobisphenol AF (U.S. Pat. No. 6,211,319 B1), aromatic tetraamines such as 3,3′-diaminobenzidene, ammonia generating compounds such as urea and other compounds (U.S. Pat. No. 6,281,296 and WO 01/27194), guanidines (U.S. Pat. No. 6,638,999) and amidines (U.S. Pat. No. 6,846,880 and U.S. Patent Publication 20070027260).
Perfluoroelastomers which may be employed in this invention are based on copolymerized units of tetrafluoroethylene (TFE), a perfluoro(alkyl vinyl ether) (PAVE) and a cure site monomer that contains nitrile groups.
Suitable perfluoro(alkyl vinyl ethers) include, but are not limited to those of the formula
CF 2 ═CFO(R f′ O) n (R f″ O) m R f (I)
where R f′ , and R f″ are different linear or branched perfluoroalkylene groups of 2-6 carbon atoms, m and n are independently 0-10, and R f is a perfluoroalkyl group of 1-6 carbon atoms.
A preferred class of perfluoro(alkyl vinyl) ethers includes compositions of the formula
CF 2 ═CFO(CF 2 CFXO) n R f (II)
where X is F or CF 3 , n is 0-5, and R f is a perfluoroalkyl group of 1-6 carbon atoms.
A most preferred class of perfluoro(alkyl vinyl) ethers includes those ethers wherein n is 0 or 1 and R f contains 1-3 carbon atoms. Examples of such perfluorinated ethers include perfluoro(methyl vinyl) ether and perfluoro(propyl vinyl) ether. Other useful ethers include compounds of the formula
CF 2 ═CFO[(CF 2 ) m CF 2 CFZO] n R f (III)
where R f is a perfluoroalkyl group having 1-6 carbon atoms, m=0 or 1, n=0-5, and Z═F or CF 3 . Preferred members of this class are those in which R f is 0 3 F 7 , m=0, and n=1.
Additional perfluoro(alkyl vinyl) ether monomers include compounds of the formula
CF 2 ═CFO[(CF 2 CFCF 3 O) n (CF 2 CF 2 CF 2 O) m (CF 2 ) p ]C x F 2x+1 (IV)
where m and n=0-10, p=0-3, and x=1-5. Preferred members of this class include compounds where n=0-1, m=0-1, and x=1.
Other useful perfluoro(alkyl vinyl ethers) include
CF 2 ═CFOCF 2 CF(CF 3 )O(CF 2 O) m C n F 2n+1 (V)
where n=1-5, m=1-3, and where, preferably, n=1.
The perfluoroelastomer further contains copolymerized units of a cure site monomer having nitrile groups. Suitable cure site monomers include nitrile-containing fluorinated olefins and nitrile-containing fluorinated vinyl ethers. Useful nitrile-containing cure site monomers include, but are not limited to those of the formulas shown below.
CF 2 ═CF—O(CF 2 ) n —CN (VI)
where n=2-12, preferably 2-6;
CF 2 ═CF—O[CF 2 —CFCF 3 —O] n —CF 2 —CFCF 3 —CN (VII)
where n=0-4, preferably 0-2;
CF 2 ═CF—[OCF 2 CFCF 3 ] x —O—(CF 2 ) n —CN (VIII)
where x=1-2, and n=1-4; and
CF 2 ═CF—O—(CF 2 ) n —O—CF(CF 3 )CN (IX)
where n=2-4.
Those of formula (VIII) are preferred. Especially preferred cure site monomers are perfluorinated polyethers having a nitrile group and a trifluorovinyl ether group. A most preferred cure site monomer is
CF 2 ═CFOCF 2 CF(CF 3 )OCF 2 CF 2 CN (X)
i.e. perfluoro(8-cyano-5-methyl-3,6-dioxa-1-octene) or 8-CNVE.
The perfluoroelastomers that may be employed in the cured articles of this invention comprise copolymerized units of i) 15 to 60 (preferably 30 to 50) mole percent perfluoro(alkyl vinyl ether) and ii) 0.1 to 5.0 (preferably 0.3 to 2.0) mole percent nitrile group-containing cure site monomer. The remaining units being tetrafluoroethylene so that the total mole percent is 100. Most preferably the perfluoro(alkyl vinyl ether) is perfluoro(methyl vinyl ether
Cured perfluoroelastomer articles of this invention also contain more than 50 phr BaSO 4 , preferably more than 60 phr BaSO 4 , most preferably between 70 and 100 phr of BaSO 4 . By “phr” is meant parts by weight of ingredient, per hundred parts by weight rubber, i.e. perfluoroelastomer. Large particle size (i.e. 0.5 to 5 micron average) BaSO 4 is preferred. Such BaSO 4 is available commercially, e.g. Blanc Fixe F and Blanc Fixe XR-N (available from Sachtleben Chemie GmbH).
Other additives may be compounded into the perfluoroelastomer to optimize various physical properties. Such additives include, stabilizers, lubricants, pigments, fillers (e.g. mineral fillers such as silicas, alumina, aluminum silicate, titanium dioxide), and processing aids typically utilized in perfluoroelastomer compounding. Any of these additives can be incorporated into the compositions of the present invention, provided the additive has adequate stability for the intended service conditions.
The BaSO 4 , crosslinking agent (i.e. curative), and optional other additives are generally incorporated into the perfluoroelastomer by means of an internal mixer or on a rubber mill. The resultant composition is then shaped and cured, generally by means of heat and pressure, for example by compression transfer or injection molding, to form the cured article of the invention. Typically the cured articles are also post cured.
Cured articles of the present invention are useful in production of gaskets, tubing, seals and other molded components.
The invention is now illustrated by certain embodiments wherein all parts and percentages are by weight unless otherwise specified.
EXAMPLES
Test Methods
Physical Properties
The following physical property parameters were recorded on K-214 O-rings; test methods are in parentheses:
T b : tensile strength, MPa (ASTM D412-92/D1414) E b : elongation at break, % (ASTM D412-92/D1414) M100: modulus at 100% elongation, MPa (ASTM D412-92/D1414) Hardness, Shore M (ASTM D412-92/D1414) Compression Set B (ASTM D395/D1414)
Sticking Force and Oozing
A K-214 O-ring was placed between two 2″×2″ stainless steel plates and a spacer inserted so that installed compression on the o-ring was 15% when the plates were bolted together. This assembly was placed in a forced air oven at 310° C. for 70 hours. The assembly was then allowed to cool for at least 3 hours and the bolts removed. Sticking force was measured in an Instron by recording the maximum force required to pull the assembly apart. Three o-rings were used for each test.
Oozing was determined by observing the surface of tested o-rings. A wet surface indicated oozing or surface degradation/melting.
The perfluoroelastomer (containing copolymerized units of tetrafluoroethylene (TFE), perfluoro(methyl vinyl ether) (PMVE) and 8-CNVE) employed in the Examples was made generally according to the process disclosed in U.S. Pat. No. 5,877,264. It contained 37.4 mole % copolymerized units of perfluoro(methyl vinyl ether) (PMVE), about 0.8 mole percent copolymerized units of 8-CNVE, the remainder being copolymerized units of TFE.
Example 1
Curable compositions were made by compounding the ingredients in a conventional manner on a 2-roll mill. The ingredients and proportions are shown in Table I.
Cured perfluoroelastomer articles were made by molding the curable compositions into K-214 O-rings and then curing. Articles of the invention contained more than 50 phr BaSO 4 (Blanc Fixe XR-HN). Comparative articles contained 50 phr or less BaSO 4 (Blanc Fixe XR-HN). The curative employed was diphenylguanidine phthalate. O-rings were press cured at 190° C. for 9-10 minutes, followed by post cure in a nitrogen oven at 305° C. for 26 hours after a slow ramp up from room temperature.
Physical properties of cured O-rings, sticking force and oozing were measured according to the Test Methods. Results are shown in Table I.
TABLE I
Comp.
Comp.
Sample A
Sample B
Sample 1
Sample 2
Formulation, phr
Perfluoroelastomer
100
100
100
100
BaSO 4
30
50
70
90
Curative 1
1.1
1.1
1.1
1.1
Physical Properties
Hardness, Shore M
63
68
78
80
M100, MPa
2.4
4.14
5.67
7.05
Tb, MPa
6.58
10.72
10.64
9.99
Eb, %
189
235
231
200
Compression Set,
15
15
17
18
25%, 200° C.,
70 hours, %
Compression Set,
Split
Split
46
58
25%, 300° C.,
70 hours, %
Sticking Force, N
280
275
120
93
Oozing
Wet
Slightly
Dry
Slightly
wet
wet
1 diphenylguanidine phthalate anhydrous | Cured perfluoroelastomers that contain high levels (i.e. greater than 50 phr) BaSO 4 exhibit good thermal sealing performance such as reduced sticking and reduced tendency for splitting. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
Adjustable needlepoint holding frame.
2. Description of the Prior Art
Needlepoint is performed on fabric work pieces of various length and width. The work piece, in the form of a sheet of fabric, is preferably held in a taut condition within the confines of the frame during the time needlepoint work is performed thereon. Prior to the present invention, a light weight, rectangular frame that was dimensionally adjustable to the particular size of a needlepoint sheet, was not available. More particularly a frame that, when not in use, could be taken apart and the frame element stored side-by-side to occupy a minimum of space.
The primary object in devising the present invention is to supply a dimensionally adjustable frame to removably support needlepoint work, as well as a frame that is light in weight and portable, can be fabricated from molded, plastic elements, and when not in use may be easily taken apart for the elements comprising the same to be stored side-by-side in parallel relationship in a space of minimum size.
SUMMARY OF THE INVENTION
A needlepoint supporting frame that is dimensionally adjustable to the size of a particular needlepoint work piece, which work piece may be removably secured to the frame after the latter is adjusted to a desired size. The needlepoint supporting frame is defined by an assembly of four elements, with each element including a light weight, elongate member having first and second ends. Each first end of an elongate member supports a head on which a spring loaded locking member is mounted.
The elements, when arranged in first and second normally disposed pairs, have the heads thereof adjustably held in interlocking relationship with the elongate member most adjacently disposed thereto, and the first and second pairs of elements defining a four sided frame. The spring-loaded locking members of the first and second pairs of elements are diagonally disposed to one another. By manually manipulating the spring-loaded fastening members of the first pair, the width of the frame may be expanded or contracted to conform to the width of the particular sheet of fabric on which needlepoint work is being performed and which sheet is desired to be held in the frame. When the spring-loaded fastening members of the second pair are similarly manipulated, the length of the frame may be expanded or contracted. The four elongate members have fastening means thereon that removably engage the marginal edge portions of the needlepoint work piece after the frame has been adjusted to accommodate the workpiece. When the frame is not in use it may be taken apart without the use of hand tools, and the elements comprising the frame stored side-by-side in parallel relationship to occupy a minimum of space. The elements are preferably formed from a polymerized resin by conventional molding techniques.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is an exploded perspective view of one of the elements that comprises the needlepoint supporting frame, which element includes an elongate member having first and second ends, a head mounted on a first end of the elongate member, and a fastening member and spring used in holding the fastening member in position on the head;
FIG. 2 is a bottom plan view of the elongate member and head shown in FIG. 1, and illustrating an elongate groove that extends longitudinally in the elongate member to be engaged by a resilient strip to hold a marginal edge portion of the fabric work piece in position on the elongate member;
FIG. 3 is a top plan view of the needlepoint supporting frame that may be manually adjusted to the desired width and length to accommodate a needlepoint work piece that is removably secured thereto;
FIG. 4 is an end elevational view of the adjustable frame shown in FIG. 3;
FIG. 5 is a transverse cross-sectional view of one of the elongate members taken on the line 5--5 of FIG. 2.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The adjustable needlepoint supporting frame A as shown in FIG. 3, includes first, second, third and fourth elongate members B-1, B-2, B-3 and B-4 that are identical in structure and each of which has a first end 10 and second end portion 12. Each elongate member B-1, B-2, B-3 and B-4 has first and second opposed side surfaces 14 and 16, and first and second edge surfaces 18 and 20.
First, second, third and fourth heads C-1, C-2, C-3 and C-4 are provided that are of identical structure, and are preferably formed as integral parts of the first, second, third and fourth elongate members B-1, B-2, B-3 and B-4 on first ends 10 thereof, as may be seen in FIG. 3.
The first, second, third and fourth heads C-1, C-2, C-3 and C-4 are of identical structure, and accordingly only the structure of the first head C-1 will be described in detail.
Head C-1 includes a transverse channel-shaped member defined by a web 22 and first and second laterally spaced flanges 24 and 26 that extend outwardly from the side edges of the web as may be seen in FIG. 1. The first and second flanges 24 and 26 have first and second axially aligned openings 24a and 26a formed therein as shown in FIG. 3 that are aligned with elongate cavity 28 formed in elongate member B-1. The center of each web 22 has a transverse guide recess 30 therein that extends between first and second openings 24a and 26a as shown in FIG. 1. An inverted channel-shaped guide 32 projects outwardly from second flange 26 and is normally disposed thereto. Guide 32 is axially aligned with first and second openings 24a and 26a. First elongate member B-1 is preferably molded from a polymerized resin and has a tooth defining rack 34 formed in the first edge surface 18 thereof, as shown in FIG. 1. First, second, third and fourth heads C-1, C-2, C-3 and C-4 have first, second, third and fourth locking members D-1, D-2, D-3 and D-4 operatively associated therewith. The locking members above-identified are identical in structure and only first locking member D-1 will be described in detail.
Locking member D-1 includes an elongate, rectangular strip 36 that has a rectangular button 38 on a first end thereof and a block 40 on a second end of the strip. The block 40 on the surface thereof most adjacent button 38, has a number of spaced teeth 42 formed thereon, which teeth are normally disposed to strip 36. Block 40 may have an opening 40a therein if desired.
A prong 44 extends outwardly from block 40 in a direction away from teeth 42. A compressed helical spring 46 encircles prong 44, with the spring being in abutting contact with the bottom 28a of cavity 20 when the first, second, third and fourth members B-1, B-2, B-3 and B-4 are disposed as shown in FIG. 3 to define the adjustable frame A. When the first, second, third and fourth elongate members B-1, B-2, B-3 and B-4 are disposed as shown in FIG. 3, the first, second, third, and fourth heads C-1, C-2, C-3 and C-4 have the first, second, third and fourth locking members D-1, D-2, D-3 and D-4 in engagement with racks 24. The first pair of elongate members B-1 and B-2 may be moved towards or away from one another by concurrently pressing inwardly on buttons 38 associated with the first and second heads C-1 and C-2. Inward movement of these two buttons results in inward movement of first and second locking members D-1 and D-2 to separate teeth 42 from racks 34 most adjacent thereto. Frist head C-1 and elongate member B-1 can now move longitudinally relative to third elongate member B-3, as fourth elongate member B-4 and fourth head C-4 move longitudinally relative to second head C-2.
Thus the width of the needlepoint holding frame A may be varied to a side to accommodate the sheet E on which the needlepoint work is being performed. By pressing inwardly on the buttons 38 a second pair of the elongate members B-3 and B-4 may be moved longitudinally relative to elongate members B-2 and B-1 to lengthen frame A to a desired degree.
The first side surfaces 14 of the first, second, third and fourth elongate members B-1, B-2, B-3 and B-4 have grooves 48 formed therein that are engaged by resilient strips 50. When the frame A has been adjusted to a desired size, marginal edge portions 52 of the sheet E are held in the grooves 48 by the resilient strip 50 as shown in FIG. 5. When the needlpoint work has been completed, the sheet E may be removed from the frame A by separating the strips 50 from the groove 48. The frame A may now be taken apart, and the elements comprising the same disposed side-by-side in compact, parallel relationship and stored in a compact state.
The use and operation of the invention has been described previously in detail and need not be repeated. | A manually adjustable, open, four-sided frame that may be dimensionally expanded or contracted to support a sheet of fabric on which needlepoint work is being performed in a taut condition. | 3 |
FIELD OF THE INVENTION
The present invention pertains generally to a skid steer loader and more particularly to an improved drive system for the skid steer loader.
DESCRIPTION OF THE PRIOR ART
A skid steer loader is a vehicle possessing a high degree of maneuverability and capable of low clearance applications. It is propelled and maneuvered by driving the wheels on one side of the vehicle at a different speed and/or in a different direction from those on the other side so as to achieve a turning motion on its own axis.
It is well known in the art that a skid steer loader is provided with a main frame comprising a center compartment partially defined by a pair of longitudinally extending, laterally spaced side beams. Adjacent to the rear portion of the frame, an engine for the loader is located for generating power to drive the loader. A bucket is disposed at the front of the loader and a manipulating unit is mounted on the top of the frame to constitute a part of the loader. Bolted to the side beams is an elongated transmission case containing therein a plurality of sprockets and endless chains adapted to operatively connect the sprockets in a conventional manner.
It has also been proposed to provide an intermediate gear reduction mechanism in the drive system into which an hydrostatic motor can be coupled to produce desired torques and speeds.
U.S. Pat. Nos. 3,635,367 and 3,895,728 disclose a drive system for the loader comprising reduction gear units which are adapted to cause the rotational speed of the hydrostatic motor to be reduced, thereby increasing the torque applied to the front and rear axles. In the afore-mentioned patents, substantial increase in torque can be achieved by providing reduction gear units; however, it still remained desirable to meet the load capacity requirement without sacrificing the low vehicle profile.
U.S. Pat. No. 4,168,757 issued to Mather et al on Sept. 25, 1979 teaches a drive system wherein a pair of reduction gear units are placed on the opposite side walls of an elongated transmission case containing therein sprockets and chains for use in power transmission. The arrangement disclosed in the Mather patent is said to have the advantages of an easier access to the elements constituting the drive system whenever replacement or repair is necessary and of a higher load capacity.
However, when such an arrangement as disclosed in the Mather patent is employed with the skid steer loader, low vehicle profile would be no longer obtainable because essential components such as an engine, a hydraulic pump or manipulating units are to be located on the transmission case at an elevated level. This results in the raising of a gravitational weight center which in turn may cause the loader to be kinetically unstable or to be turned over in the worst circumstances.
The loader described and shown in the Mather patent also has a problem calling for the provision of a relatively longer output shaft extending from the hydrostatic motor into the transmission case and the provision of bearing means for rotatably supporting the output shaft to prevent it from being bent or sagged by bending moments applied thereto particularly during actuation of a disk type brake device. This makes the drive system for a loader bulky and expensive.
The loader of the cited patent is further disadvantageous in that axle housings welded to the transmission case and stub axles journaled in the housings are not able to avoid a substantial increase in their length in order to meet the vehicle width requirement.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the invention to provide a discrete drive system for a skid steer loader which is designed to lower the gravity center to produce a low vehicle profile and thus stabilize loading or running operation performed by the loader.
Another object of the invention is to provide a drive system for a skid steer loader comprising a brake device which includes a circular drum secured in place to the reduction gear, a flexible band wound circumferentially on the circular drum, and an actuation means pivotably journaled through an outer casing of the gear reduction means.
A further object of the invention is to provide a drive system for a skid steer loader in which an output shaft of the gear reduction means is coupled directly to a front or rear axle, rather than through any of the endless chains, thereby eliminating the need to have drive sprockets integrally formed with the output shaft and, consequently, simplifying the transmission cases in their internal configuration.
In one aspect of the present invention, there is provided a drive system for a skid steer loader which comprises: a main frame for the loader; a pair of parallelly spaced, elongated transmission cases integrally formed with the main frame for transmitting drive force from a hydrostatic motor to front and rear stub axles; means for interconnecting the bottom surfaces of the pair of transmission cases to define a longitudinally extending compartment, said compartment receiving at least partially an engine for the loader and a hydraulic pump; and gear reduction means mounted on the inner side wall of each of the transmission cases, said gear reduction means having a pair of drive sprockets operatively connected to driven sprockets on the stub axles.
In another aspect, the present invention contemplates a drive system for a skid steer loader which comprises: a main frame for the loader; a pair of parallelly spaced, elongated transmission cases integrally formed with the main frame for transmitting drive force from a hydrostatic motor to front and rear stub axles; means for interconnecting the bottom surfaces of the pair of transmission cases to define a longitudinally extending compartment, said compartment receiving at least partially an engine for the loader and a hydraulic pump; and gear reduction means mounted on the inner side wall of each of the transmission cases in axial alignment with either one of the front or rear stub axle to achieve a direct drive of the aligned axle.
The gear reduction means is provided with an outer casing rigidly secured to the inner side wall of the transmission cases, a first output shaft having an inner end extending into the transmission cases and a second output shaft associated with the hydrostatic motor. In this embodiment, the first output shaft is coupled directly to either one of the front or rear axle, rather than any of the endless chains, which has a sprocket to drive the non-coupled axle by use of a single endless chain.
Many other features, advantages and additional objects of the present invention will become manifest to those versed in the art in light of the following detailed description of the present invention with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a skid steer loader incorporating the improved drive system of the present invention;
FIG. 2A is a partially exploded perspective view of the main frame of the skid steer loader showing major structural elements of the loader associated with the improved drive system as viewed from the rear thereof;
FIG. 2B is a cross-sectional view of the main frame associated with the novel drive system having a pair of transmission cases integrally formed with the side beams of the main frame;
FIG. 3 is a top plan view showing an embodiment of the present drive system incorporating a pair of transmission cases which are spaced apart and interconnected by a plate member, the cases having portions thereof removed for clarity;
FIG. 4 is a plan view, partially in section, of the gear reduction means mounted on the inner side wall of the transmission cases, the gear reduction means incorporating a band brake means in place of the disk brake employed in the conventional loaders;
FIG. 5 is a partial perspective view illustrating the brake means of the present invention with portions thereof removed for clarity; and
FIG. 6 is a similar view as depicted in FIG. 3, showing an alternative embodiment of the present drive system in which an output shaft of gear reduction means is coupled directly to the front or rear axle.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawings wherein like reference characters designate like or corresponding parts throughout the several views, FIG. 1 illustrates the general construction of a skid steer loader incorporating the present invention.
As is shown in FIG. 1, the skid steer loader generally comprises a main frame 10, front and rear wheels 20 and 30, a bucket 40, an operating unit 70 and an engine not shown for simplicity. The front and rear wheels 20 and 30 are carried on the outer ends of the front and rear stub axles which are rotatably journaled in the axle housings of the main frame 10. The bucket 40 is pivotably articulated to the booms 50 and 60 to perform the loading operation in response to displacement of the hydraulic cylinders.
The detailed description of the general construction for a loader incorporating the present invention is made in close reference to the corresponding description made in the aforementioned U.S. Pat. No. 4,168,757 for the sake of convenience.
FIG. 2A and FIG. 2B illustrate perspective and cross-sectional views of major structural elements of the loader comprising a general type of main frame associated with the novel drive system. The main frame is provided with a pair of laterally spaced longitudinally extending side beams 11 and 12 and a laterally extending cross beam 13 disposed at the rear of the side beams 11 and 12. A rear cover 80 is releasably attached to the cross beam 13 of the main frame.
Connection means 102 is secured to the lower ends of the side beams 11 and 12 by suitable securing means such as welding, thereby providing a base to accommodate an engine, hydraulic pumps and the like. As clearly shown in FIG. 2B, welded to the inner surfaces of the side beams 11 and 12 are a pair of right-angled covering plates 14 and 15, each of which includes an elongated vertical extension and a horizontal extension formed integrally with the vertical extension at a right angle. Onto the outer surfaces of the side beams 11 and 12, axle housings 112 and 114 are secured to rotatably journal the front and rear stub axles as is known in the art.
In such an arrangement, the pair of covering plates 14 and 15 are adapted to define a first and a second transmission cases 100 and 100 in cooperation with the side beams 11 and 12 serving as outer side walls and the connection means 102 serving as the bottom base of the transmission cases.
Referring to FIG. 3 which shows a particular embodiment of the present invention, the discrete drive system for a loader comprises a first and a second elongated transmission cases 100 and 100 containing therein endless chains and sprockets for power transmission. Connection means 102 is provided to rigidly interconnect the bottom portions of the first and the second transmission cases in a spaced relationship. It should be noted that connection means 102 may interconnect the side walls or top walls of the transmission cases when it is necessary. Mounted on the inner side walls of the transmission cases are a first and a second gear reduction means 200 and 200 which provide drive power to the front and rear axles at reduced speeds and enhanced torques. A first and a second hydrostatic motors 300 and 300 are coupled to each of the gear reduction means 200 and 200 as is known in the art.
It may be understood that the first and the second transmission cases are substantially the same in configuration as well as internal structure thereof. For the sake of convenience, only the first transmission case will be set forth hereinbelow in connection with the corresponding first gear reduction means and the first hydrostatic motor.
The first transmission case 100 is composed of an inner side wall 104 and an outer side wall 106 laterally spaced therefrom. A top wall 108 and a bottom wall 110 are welded to or integrally formed with the upper and lower ends of the side walls 104 and 106 to form a longitudinally extended transmission case into which is contained chain transmission means. Front and rear axle housings 112 and 114 outwardly extending from the outer side wall 106 include central bores through which are rotatably journaled front and rear stub axles 116 and 118 carrying drive sprockets 120 and 122 at their inner ends and wheel plates 124 and 126 at their outer ends.
As may be appreciated from FIG. 3, lateral spacing of the transmission cases 100 and 100 helps shorten the length of the axle housings 112 and 114 and the stub axles 116 and 118. This results in the cost effective fabrication and easier maintenance of the front and rear axles 116 and 118 journaled in the axle housings 112 and 114 through bearing means 132.
The bottom portion of the first transmission case 100 is rigidly connected to that of the second transmission case 100 by means of connection means 102 so that a compartment which is opened at its longitudinal ends may be formed between both transmission cases 100 and 100. While not exclusive in the present invention, connection means 102 may be a metal plate having sufficient stiffness to bear vertical loads and/or bending moments. The compartment is adapted to receive at least partially such main elements for the loader as an engine, hydraulic pumps, hydrostatic motors and the like which are conventionally mounted on a common transmission case at an elevated level. Thus, the overall height and gravity center of the loader may be considerably lowered to achieve a low vehicle profile and stable operation.
A first and a second gear reduction means 200 and 200 are mounted on the respective inner side wall 104 of the transmission cases 100 and 100. The first gear reduction means 200 includes an output shaft extending into the first transmission case 100 and carrying at the inner end thereof drive sprockets 220 and 222 which are operatively coupled to driven sprockets 120 and 122 through endless chains 128 and 130. Specifically, a first endless chain 128 connects the drive sprocket 220 to the driven sprocket 120 carried at the inner end of the front stub axle 116. The drive sprocket 222 is connected by a second endless chain 130 to the driven sprocket 122 carried at the inner end of the rear stub axle 118.
Hydrostatic motors 300 and 300 are mounted on the gear reduction means 200 and 200 to provide driving force to the gear reduction means. First and second pumps(not shown) are hydraulically connected by hoses to the first and the second hydrostatic motors 300 and 300.
As best shown in FIG. 4, the first gear reduction means 200 is a generally elongated structure comprising an outer casing 202 secured to the inner side wall 104 of the first transmission case 100 by means of bolts 204 and 206 which extend through openings in the flange 202a of the outer casing 202 to engage complementary threaded openings in the inner side wall 104 of the transmission case 100. The outer casing 202 includes a first hub 210 formed on the forward wall 202b of the casing 202, a second hub 212 provided at the rear wall 202c in axial alignment with the first hub 210 and a third hub 232 parallel to the second hub 212.
Journaled in the first and the second hubs 210 and 212 is an output shaft 208 which is held in place by a retainer 224 and an end cap 225. First and second bearings 214 and 216 rotatably support the output shaft 208. The output shaft 208 has a reduction gear 218 mounted thereon and carries at its inner end drive sprockets 220 and 222 which are operatively connected to the driven sprockets carried on the front and rear axles through the first and second endless chains as set forth hereinabove.
Mounted adjacent to the second hub 212 is a hydrostatic motor 300 which is bolted on the outer casing 202 by bolts 302 and 304. An output shaft 226 of the hydrostatic motor 300 extends into the outer casing 202 in a decreased distance without protruding into the transmission case 100. The output shaft 226 is tapered and has a smallest diameter at its free end. Slidingly coupled to the output shaft 226 is a pinion gear 228 which is integrally formed with the boss member 228a having a central bore complementary to the tapered shaft 226. The pinion gear 228 is retained in place by a nut 230 engaging the stud of the output shaft 226 and is normally meshed with the reduction gear 218 of the output shaft 208.
In accordance with the present drive system, brake means is incorporated in the gear reduction means 200 as shown in FIG. 4 and particularly in FIG. 5. The brake means comprises a circular drum 234 which is secured coaxially to one side of the reduction gear 218 by means of bolts 236 and 236. Circumferantially wound around the drum 234 is a flexible band 238, one end of which is tied on the support bar 250, the other end of which is held by tension means for applying tensile force to the flexible band 238.
The tension means comprises an eccentric cam shaft 240 pivotably mounted on the outer casing 202 of the gear reduction means 200. The eccentric cam shaft 240 includes a middle extension 242 journaled through the third hub 232 of the outer casing 202, an interior shank 244 eccentrically extending into the casing from the middle extension 242 to hold a terminal end of the flexible band 238, and an exterior shank 246 concentrically outwardly extending from the middle extension to affix an actuation lever 248 thereto.
It should be noted that the brake means may take the form of disk brake well known in the art, in which case the output shaft 226 of the hydrostatic motor 300 should be further extended into the transmission case 100 and a disk plate has to be attached to the free end of the output shaft 226.
Referring now to FIG. 6, there is shown an alternative embodiment of the present drive system wherein a first and a second gear reduction means are mounted on the inner side walls of the transmission cases 100 and 100 so that the output shaft 208 may be axially aligned with the rear stub axle 118. The output shaft 208 has a toothed end which engages an array of teeth provided at the inner end of the rear stub axle 118 to directly drive the rear wheel. Coupling between the output shaft of the gear reduction means and the rear stub axle may be made by any of known type of coupling means such as a spline shaft or a serration.
In such an arrangement, the sprocket 122 carried on the rear axle 118 functions as a drive sprocket to rotate the driven sprocket 120 of the front axle 116 by use of a single endless chain 134. Therefore, there is no need to provide drive sprockets on the outer end of the output shaft 208; and only an endless chain is required to transmit the drive power to the respective driven axle.
While the output shafts of the first and second gear reduction means 200 and 200 have been shown in FIG. 6 as coupled to the rear and front stub axles respectively, they can, of course, be coupled in different manner without departing from the scope of the invention. For example, the output shaft of the first gear reduction means may be coupled to the front axle in the first transmission case whereas that of the second gear reduction means may be connected to the rear axle in the second transmission case. Alternatively, all of the output shafts of the reduction means may be coupled, if desired, to either the front axles or the rear axles in both transmission cases. | The present invention is directed to a discrete drive system for a skid steer loader comprising a pair of independent transmission cases interconnected by a plate member at a spaced relationship. The transmission cases enclose chain and sprocket drives for the loader and have the axle housings outwardly extending from the outer side walls thereof. A pair of gear reduction means are mounted on the inner side walls of the transmission cases to provide a drive power to the front and rear stub axles at reduced speeds. The gear reduction means incorporates an improved brake device including a circular drum secured to the reduction gear, a flexible band wound around the drum and an eccentric cam shaft for actuation of the brake device. Coupled to the gear reduction means are a pair of hydrostatic motors having output shaft extending into the outer casings of the reduction means. Each of the output shafts has a tapering shape and terminates at its threaded end to facilitate the mounting of the pinion gear. | 4 |
The present invention relates in general to the art of pulling one member out of another member in which it is held, and it relates more particularly to a new and improved method and tool for removing a key lock cylinder assembly from the supporting structure in which it is mounted.
BACKGROUND OF THE INVENTION
Combination ignition and steering wheel locks as now used on most automotive vehicles include a key operated cylinder assembly which fits into an opening in the steering column and is locked in place by means located within the steering column. In some vehicles replacement of such cylinder assemblies requires the removal of the steering wheel, a time consuming and expensive operation. Since the lock cylinder assembly itself is a relatively inexpensive part any damage which occurs thereto during removal is of little consequence. On the other hand, attempts to physically break the lock assembly free from the steering column have in the past generally resulted in damage to the steering column itself.
OBJECTS OF THE INVENTION
An object of the present invention is, therefore, to provide a new and improved method and tool for removing lock cylinder assemblies from the supporting structures in which they are fastened.
Another object of the present invention is to provide a new and improved tool which is quickly attachable to a lock cylinder assembly and which can be used to pull the assembly from the support structure in which it is mounted.
SUMMARY OF THE INVENTION
There is provided in accordance with the present invention a new and improved method and tool for removing a lock cylinder assembly from a supporting structure such as a steering column in which it is secured by means of tabs or the like on the lock cylinder itself. The tool includes a generally cylindrical collet having a plurality of resilient fingers which grip the end of the lock cylinder when the collet is pressed thereon. After the collet has been placed on the lock cylinder a body cylinder is placed over the collet with a thin, co-axial, cylindrical flange on the body member extending between the collet fingers and the surrounding surface of the support. A bolt is then inserted through an axial opening in the outer end of the body member into a threaded hole in the end of the collet, and as the bolt is tightened, the collet is drawn into the body which prevents the resilient fingers from expanding out of engagement with the lock cylinder. As the collet is moved into the body member and thus exerts an outward force on the lock cylinder the locking tabs on the lock cylinder assembly are broken off and the cylinder assembly is withdrawn from the steering column. After removal of the lock cylinder assembly a new cylinder assembly may be simply pressed in place in the steering column. In replacing the lock cylinder in this manner, no damage is done to the steering column or to the parts therof which are operated by the lock cylinder mechanism.
BRIEF DESCRITPION OF THE DRAWING
Further objects and advantages and a better understanding of the present invention can be had by reference to the following detailed description, wherein:
FIG. 1 is a fragmentary perspective view of a combination ignition and steering wheel lock with the finger ring removed;
FIG. 2 is an elevational view of a lock cylinder with the collect portion of the tool of the present invention attached thereto, the surrounding structure being shown in cross-section;
FIG. 3 is a cross-sectional view of the tool of the present invention in position to remove a lock cylinder;
FIG. 4 is an enlarged cross-sectional view of the end of one of the fingers of the collet; and
FIG. 5 is a view of a lock cylinder after removal thereof from a steering column by the method and tool of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to FIG. 1, there is shown a portion of a steering wheel 10 and a steering column 11 to which it is mounted. A combination ignition and steering wheel lock cylinder assembly 12 is mounted in the steering column and connected internally of the steering column to a mechanism for locking the steering wheel 10 against rotation when the lock assembly 12 is in locking position. A finger ring 13 is positioned over the lock cylinder assembly and snapped onto an annular flange 17 at the outer end of the lock assembly to facilitate placement of a key in the key slot 14 in the cylinder assembly. The ring 13 includes a pair of finger engaging lugs 15 and 16 to facilitate turning of the key after it has been placed in the slot.
Referring to FIG. 2, a portion of the steering column 11 is shown in cross-section and includes a cylindrical recess 19 in which the lock cylinder assembly 12 fits. In order to lock the cylinder assembly 12 within the steering column the cylinder assembly 12 includes an outwardly biased spring loaded tab 21 which extends into a lateral slot 22 in the steering column and a spring loaded tab 23 which engages an inwardly facing shoulder on the steering column 11. In some vehicles such as those manufactured in recent years by the General Motors Corporation the tabs 21 and 23 can only be released by first removing the steering wheel from the steering column and then releasing the tabs from within the steering column.
In order to remove the lock cylinder assembly 12 from the steering column in accordance with the method of the present invention, the finger ring 13 is first removed by means of a suitable prying tool such as a screw driver. A collet member 25 having a plurality of spring fingers 26 arranged in a cylinder is then pressed onto the end of the lock cylinder 12 such that gripping means at the end portions of the fingers overlie an annular flange 27 at the outer or distal end of the lock cylinder assembly. The ends of the fingers fit within the annular space surrounding the lock cylinder. As best shown in FIG. 4, each finger 26 includes an internal rectangular groove 28 near the end which fits over the annular flange 27 at the end of the lock cylinder assembly 12. The forward end or nose of each finger 26 is rounded as shown at 29 to provide a camming surface which causes the fingers to spring out as the collet is pressed against the end of the lock cylinder. The fingers 26 then contract as the slots 28 align themselves with the flange 27. In practice, it is found that the collet may be easily and quickly snapped onto the flange 17 by simultaneously pushing and turning the collet.
After the collet 25 has been placed on the lock cylinder as shown in FIG. 2 and the fingers 26 are in their normally unstressed position as there shown, a sleeve-like body member 32 having a cylindrical internal recess 33 is placed over the collet 25. At the front end the body member 32 has a thin coaxial flange 34 which is adapted to extend over the end portions of the fingers 26 when the collet is attached to the lock cylinder assembly. The outer end portion 36 of the collet 25 is threaded to receive a bolt 37 which extends through a hole 38 in the outer end portion of the body member 32. As shown, the body member 38 may be formed by a tubular sleeve portion and a solid end plug suitably welded together. After the body member 32 has been placed over the collet the bolt 37 is inserted through the opening 38 into the aligned threaded opening in the end portion 36 of the collet 25 and the bolt 37 is rotated to draw the collet 25 into the body member 32. In order to prevent the collet 25 from rotating at this time, a set screw 40 extends through the body member 32 into a longitudinal slot 41 in the outer surface of the collet 25. As the nut is tightened and the collet 25 is pulled into the body member 32 the fingers 26 are initially prevented from expanding by means of the flange 34 on the body member 32. As the collet is pulled into the body member and an outward axial force is exerted on the lock cylinder assembly, the body portion of the cylinder assembly inwardly of the tabs 21 and 23 ordinarily breaks off and falls down into the steering column. The lock cylinder is then free to be removed.
After the lock cylinder has been removed it will generally have the appearance shown in FIG. 5 with portions of the inner end broken away. A new lock cylinder assembly may now be installed by simply inserting the new one in place in the recess 19 in the steering column. The entire operation can be done very quickly and no permanent damage is done to the steering column or to the mechanism contained therein.
While the present invention has been described in connection with a particular embodiment thereof, it will be understood by those skilled in the art that many changes and modifications may be made without departing from the true spirit and scope of the present invention. Therefore, it is intended by the appended claims to cover all such changes and modifications which come within the true spirit and scope of this invention. | A lock cylinder assembly is removed from a steering column by means of a tool incorporating a collet member having a plurality of spring fingers which grip the end of the lock cylinder and a body member having a cylindrical flange which fits between the end of the collet and the supporting structure surrounding the lock to hold the fingers in engagement with the lock cylinder as a bolt is tightened to pull the collet into the body. | 8 |
BACKGROUND OF THE INVENTION
The present invention relates to hand tools, and in particular to an adaptor for use with pliers or multipurpose hand tools to turn screwdriver bits, small socket wrenches, and the like.
It is well known to use a single handle to drive a selected one of a set of screwdriver bits or wrenches of various sizes, to save the cost of having several handles. It is also often desirable thus to minimize the weight and number of tools used or carried. Adaptors intended to be gripped by drill chucks are also available to receive such bits. Some multipurpose hand tools previously available have also included drive members for driving small socket wrenches. Some of these drives, while useful, add undesirably to the size of the multipurpose tools of which they are part, making the multipurpose tools less convenient to carry.
Folding multipurpose tools are disclosed, for example, in Leatherman U.S. Pat. Nos. 4,238,862, and and 4,888,869. Many generally similar tools are available.
Most such multipurpose tools do not include more than two or three sizes of straight screwdriver blades and one or two sizes of Phillips screwdrivers. Such multipurpose tools do not usually include any socket wrench drives, and thus they are not readily useful to drive many of the various different types or sizes of screwdriver bits and socket wrenches available. However, it would be advantageous to be able to drive such screwdriver bits, socket wrenches or other small tools using an available multipurpose tool as a drive handle. This would be particularly advantageous to avoid carrying several special drive handles where it is important to minimize the weight of tools carried, as in bicycle touring.
Depending on the space available around a screw, bolt, or nut it may be necessary or desirable for a socket or screwdriver to be adjustable optionally to be aligned with a handle or to extend at an angle to one side. While some adaptors have been available previously to enable screwdrivers or small socket wrenches to be driven by a folding multipurpose tool, these arrangements have not been strong enough, or have been limited to axially aligned engagement with a screwdriver included in a multipurpose tool, or have been otherwise limited in their usefulness.
What is needed, then, is a suitably strong adaptor by which various small tool bits, screwdrivers, or sockets can be driven, using another hand tool as a handle for the adaptor, and with which such tool bits can be aligned at selected angles with respect to the hand tool. Preferably, such an adaptor could be used with multipurpose tools such as those which are already well known and widely available and would be small enough to be carried conveniently.
SUMMARY OF THE INVENTION
The present invention overcomes the aforementioned shortcomings of the prior art and supplies an answer to the need for a small and easily used, but strong, adaptor to enable various tool bits to be driven by a single hand tool. As used herein a tool bit means a screwdriver bit or a small wrench socket, or a similar tool which may be one of a set of such tools of several sizes, all of which can be driven in rotation when mated with a suitable drive member. An adaptor according to the present invention includes a drive plate having a driven end and a driving end, with a tool bit-engaging member attached to the drive plate near its driving end. A pair of generally parallel arms are included at the driven end of the drive plate and are available to engage or be engaged by a hand tool which is to be used as a handle for the adaptor.
In one embodiment of the present invention the tool bit-engaging member includes a hexagonal socket of an appropriate size for receiving the shanks of interchangeable screwdriver bits and other tool bits of the same size.
In a preferred embodiment of the invention the tool bit-engaging member is able to pivot with respect to the drive plate, between an in-line orientation and an offset or angled position.
Another aspect of the invention is a locking mechanism provided to hold the tool bit-engaging member in an in-line orientation or in a selected angled orientation with respect to the drive plate when the adaptor is being used. In one such locking mechanism a spring-loaded tooth engages a selected notch on the drive plate, while a collar surrounding the body of the tool bit-engaging member keeps the tooth aligned and is useful to disengage the tooth from a notch.
Preferably, the driven end of the drive plate includes a projection arranged to engage a handle of a multipurpose tool to keep the adaptor securely mated with the multipurpose tool.
In one embodiment of the invention, the parallel arms defined on the driven end of the adaptor drive plate are arranged to fit snugly along opposite sides of a pair of jaws of a multipurpose tool with which the adaptor is mated.
A feature of one embodiment of the invention is a stiffener portion of the drive plate that increases the amount of torque that can be transmitted to a tool bit in an offset or angled position.
The foregoing and other objectives, features, and advantages of the invention will be more readily understood upon consideration of the following detailed description of the invention, taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
FIG. 1 is a perspective view of a tool bit drive adaptor according to the present invention, together with a portion of a tool bit.
FIG. 2 is a perspective view of the tool bit drive adaptor shown in FIG. 1 in place between the handles of a folding multipurpose tool.
FIG. 3 is a side elevational view of the folding multipurpose tool and tool bit drive adaptor shown in FIG. 2, with the handles and jaws of the folding multipurpose tool partially separated from each other.
FIG. 4 is a side elevational view, at an enlarged scale, of the tool bit drive adaptor shown in FIG. 3, together with a portion of the folding multipurpose tool, shown partially cut away.
FIG. 5 is a bottom view of the tool bit drive adaptor and portion of a multipurpose tool shown in FIG. 4.
FIG. 6 is a view of the tool bit drive adaptor and portion of a multipurpose tool shown in FIG. 4, rotated 180° about a longitudinal axis of the tool bit drive adaptor to show the opposite side from that shown in FIG. 4.
FIG. 7 is a perspective view of the tool bit drive adaptor shown in FIG. 1, together with a folding multipurpose tool of a somewhat larger size than the multipurpose tool shown in FIG. 2.
FIG. 8 is a view similar to that of FIG. 4, showing the position of the tool bit drive adaptor relative to the positions of the handles and jaws of the multipurpose tool shown in FIG. 7.
FIG. 9 is a bottom plan view of the tool bit drive adaptor, together with a portion of the multipurpose tool shown in FIG. 7.
FIG. 10 is a view similar to that of FIG. 6, showing the tool bit drive adaptor of the invention together with the multipurpose tool shown in FIG. 7.
FIG. 11 is a sectional view of a portion of the tool bit drive adaptor shown in FIGS. 1-10, taken along line 11--11 of FIG. 1.
FIG. 12 is a view of the collar and locking member of the tool bit drive adaptor shown in FIGS. 1-11, taken in the direction of line 12--12 of FIG. 1.
FIG. 13 is a detail, at an enlarged scale, of the collar and locking member shown in FIG. 11.
FIG. 14 is a view similar to FIG. 11, but showing the corresponding portion of a tool bit drive adaptor which is an alternative embodiment of the present invention.
FIG. 15 is a view similar to FIG. 14, showing the portion of a tool bit drive adaptor shown in FIG. 14 with its tool bit-engaging member in a locking position with respect to the adaptor drive plate.
FIG. 16 is a section view taken along line 16--16 of FIG. 15.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIGS. 1-6 of the drawings which form a part of the disclosure herein, a tool bit drive adaptor 20 includes a tool bit-engaging member 22 attached to a driving end 23 of a drive plate 24. A hexagonal socket 26 is defined in an outer, or driving, end of the tool bit-engaging member 22 to receive a hexagonal end or base 28 of a tool bit which may be a screwdriver or a wrench belonging to a set of similar screwdrivers or wrenches all having bases of a size to fit the socket 26, so that a single handle may be used to drive any of the screwdrivers or wrenches.
Within the socket 26, a circular spring 30 is located within a radial groove deep enough to allow the circular spring 30 to expand to permit the base 28 of the screwdriver or other tool bit to enter into the socket 26, after which the elastic grip of the spring 30 helps to retain the base 28 within the socket 26.
The drive plate 24 includes a pair of substantially parallel fork arms 32 and 34, located at a driven end 36 of the drive plate 24 and defining a jaw-receiving throat 39 between them. A hole 35 is provided in the fork arm 32 to receive a lanyard to keep the adaptor 20 handy. The drive plate 24 is formed as by stamping or pressing an appropriately shaped unitary blank cut from a sheet of metal such as steel of an appropriate thickness, for example 0.094 inch. A retaining tab 38 is bent to extend generally perpendicularly upward from the fork arm 32, and a portion of the drive plate 24 is bent similarly upward to form a stiffener 40 extending along the length of the drive plate 24 including the fork arm 34. The stiffener 40 may have a width 41 of about 0.25 inch, for example. Provision of the stiffener 40 adds significantly to the ability of the adaptor 20 to transmit torque to a tool bit without damage to or failure of the drive plate 24, particularly when the tool bit-engaging member is in an angled position rather than in line with the length of the drive plate 24.
As may best be seen in FIGS. 1, 5, and 6, an outer end portion of the fork arm 34 is offset slightly out of the principal plane 37 of the drive plate 24 to act as a spacer 41 having an upper, or spacer surface 42 whose function will be explained presently. A pair of spacer bumps 44 are also provided in the drive plate 24 near its driving end 23, extending upward away from its bottom surface 61, and may be formed by stamping or coining the blank as a part of the process of manufacturing the drive plate 24.
As shown in FIGS. 2 and 3, the adaptor 20 is used with a multipurpose folding tool such as a Leatherman™ Pocket Survival Tools 46 which includes a pair of folding handles 48, 50 of sheet metal channel construction. The tool 46 also includes a pair of interconnected jaws 52 and 54 each having a respective base 56, 58 about which one of the handles 48, 50 can rotate, between a folded position shown in FIGS. 2 and 3 and an extended position (not shown) in which the handles 48, 50 extend from the bases 56, 58 for operation of the jaws 52, 54. An inner surface 60 of the fork arm 34 extends closely alongside the pivotally interconnected portions of the jaws 52, 54 of the Leatherman® Pocket Survival Tools™ 46, and inner surfaces 62 and 66 extend closely alongside portions of the opposite side of the pivotally interconnected portions of the jaws 52, 54, visible in FIG. 3. Opposed marginal surfaces 55 of the handles 48 and 50 also rest upon opposite faces 59 and 61 of the drive plate 24, in contact therewith adjacent the throat 39. The spacer portion extends alongside the handle 48, and the marginal surfaces 55 of the handles 48, 50 rest upon or close to the opposite faces 59 and 61 of the drive plate 24 along both of the legs 32 and 34. At the same time, as shown in FIGS. 3 and 4, the retaining tab 38 extends within the handle 48, whose shape includes an inward jog defining an angled face 64, so that the retaining tab 38 prevents the drive plate 24 from being withdrawn from its position between the handles 48, 50, and bases 56, 58 of jaws 52, 54, while the throat 39 defined between the fork arms 32 and 34 rests against the pivotally interconnected portions of the jaws 52, 54. The location of the drive plate 24 is thus precisely established with respect to the jaws 52, 54 and the handles 48 and 50.
Referring next to FIGS. 7, 8, 9, and 10, a larger multipurpose tool 70, such as a Leatherman® Super Tool™, has a pair of handles 72 and 74 of sheet metal channel construction and a pair of pivotally interconnected jaws 76 and 78, each having a base 80, 82 about which a respective one of the handles 72, 74 can rotate between a folded position as shown in FIG. 7 and an extended position (not shown). The drive plate 24 of the adaptor fits around the jaws 76 and 78 between their bases 80, 82 and between the handles 72 and 74 in much the same way in which it fits around the jaws 52 and 54 in the multipurpose tool 46 as described above, but since the handles 72 and 74 are wider and longer than the handles 48 and 50, they extend over a greater portion of the drive plate 24, as may be seen in FIGS. 7, 8, 9, and 10. An angled face portion 84 on each side of each handle 72 and 74 interconnects a wider portion 86 of each handle with a narrower portion 88, where the respective jaw 76 or 78 is located. The retaining tab 38 extends upward within the handle 72 in position to contact the inner side of the angled portion 84 to retain the drive plate 24 in place with respect to the handle 72. The narrower portion 88 of each of the handles 72, 74 extends beyond the angled portion 84 on each side, and the inwardly facing margins 90 of the narrower portion 88 of the handle 72 rest against the spacer bumps 44, while a part of the margin 92 of the wider portion 86 of the handle 72 rests against the spacer surface 42, as shown best in FIG. 10.
At the same time, the corresponding margins 90 and 92 of the other or bottom handle 74 extend closely parallel with the bottom surface 61 of the drive plate 24, and the base 82 of the jaw 78, adjacent the pivotally interconnected portions of the jaws 76, 78, presses against the bottom surface 61 of the drive plate 24 adjacent the throat 39. The bottom surface 61 thus acts as a spacer in opposition to the spacer surface 42 and spacer bumps 44. The margin 92 of the handle 72 also presses against the spacer surface 42, counterbalancing the forces of the margins 90 against the spacer bumps 44 and keeping the handle 72 parallel with the principal plane 37 of the drive plate 24 and with the bottom handle 74. Pressure on the handle 74 thus squeezes the base 82 of the jaw 78 against the bottom surface 61, while pressure against the upper handle 72 presses its margins 90, 92 against the spacer bumps 44 and spacer surface 42, so that a firm grip squeezing the handles 72 and 74 together holds the drive plate 24 firmly between the handles 72 and 74 to provide a solid interconnection of the multipurpose tool 70 to the adaptor 20.
With the handles 72 and 74 so located the inner surface 60 of the fork arm 34 rests snugly alongside the pivotally interconnected portions of the jaws 76 and 78, while the inner surfaces 62 and 66 of the fork arm 32 rest snugly along the pivotally interconnected portions of the jaws 76 and 78 on the opposite side of the multipurpose tool 70.
Referring now also to FIG. 11, the tool bit-engaging member 22 has a body that is generally cylindrical in shape and includes a base portion 100 having a top leg 102 and a bottom leg 104, defining between them a slot 105 which snugly receives the driving end portion 23 of the drive plate 24. The tool bit-engaging member 22 is attached to the drive plate 24 by an attachment screw 106 that extends through a hole defined in the bottom leg 104 and a pivot hole 108 defined in the drive plate 24, and is engaged in a threaded bore 110 defined in the top leg 102. The tool bit-engaging member 22 is thus able to be pivoted about the axis 111 of the screw 106 with respect to the drive plate 24, between an in-line position as shown in FIG. 1 and a position in which the tool bit-engaging member 22 extends away from such an in-line position at an angle 112.
The tool bit-engaging member 22 is ordinarily kept located in the in-line position, or in either of a pair of optional offset-angled positions A, B shown in FIG. 11, by a locking device incorporated in the adaptor 20. Three notches 118, 120, 122 are defined in the outer margin of the drive plate 24, at positions separated from one another by angles of 45° about the central axis 111 of the screw 106, as may be seen best in FIG. 11. When the tool bit-engaging member 22 is aligned with the drive plate 24 in the in-line position previously mentioned, or in either of the angularly offset positions, A, B, a locking tooth 124 is matingly engaged in the notch 118, 120 or 122. The locking tooth 124 is part of a T-shaped locking member 126 which is located in the slot 105 defined between the top leg 102 and bottom leg 104, with the ends of the arms 128 of the T extending outward beyond the slot 105 and captured between an outer wall 130 of a collar 132 and a ring 134 fitting tightly within the collar 132, against the outer wall 130. The collar 132 thus keeps the locking member 126 between the legs 102 and 104. The collar 132 may be knurled, as shown at 137, to make it easy to grip.
The collar 132 and ring 134 as a unit are slidably disposed about the tool bit-engaging member 22, but are prevented from moving with respect to one another or with respect to the locking member 126, as by the margin of the outer wall 130 being crimped inward against the ring 134 at 136, as shown in FIGS. 12 and 13, so that the ends of the arms 128 are caught between the ring 134 and the collar 132, and the collar 132 is not free to rotate about the tool bit-engaging member 22. For a more secure grip on the ends of the arms 128 the collar 132 could also be punched inward as shown at 138. A helical spring 140 is disposed within a longitudinal bore located between the legs 102, 104 and extends centrally along the tool bit-engaging member 22, as shown in FIG. 11, to urge the locking member 126, and with it the collar 132 and its associated ring 134, toward the screw 106. The spring 140 thus urges the locking tooth 124 into engagement with a respective one of the notches 118, 120, 122 when the tool bit-engaging member 22 is located at a corresponding angle 112 with respect to the drive plate 24. Preventing the collar 132 from rotating with respect to the tool bit-engaging member 22 makes it easier to push the collar 132 longitudinally along the tool bit-engaging member 22 to disengage the locking tooth 124 from one of the notches 118, 120 or 122.
In a tool bit drive adaptor 150 which is an alternative embodiment of the present invention, as shown in FIGS. 14, 15, and 16, a drive plate 152 includes a locking body 154, which may be a raised bump formed in the drive plate 152 by appropriate means, similar to formation of the spacer bumps 44. A pivot hole 156 extends through the drive plate 152 and is elongated, allowing the screw 106 in the tool bit-engaging member 22 to move longitudinally along the drive plate 152 in response to axial pressure in the direction indicated by the arrow 158 shown in FIG. 15.
A ball 160 is located within the bore 142 in the tool bit-engaging member 22, in contact with the outer end 162 of a spring 140, which urges the ball 160 toward the margin of the drive plate 152. Substantially semicircular detent notches 164, 166, and 168 are defined by the margin of the drive plate 152, in an in-line position, a 45° offset angle position, and a 90° offset angle position with respect to a central axis of rotation 170 located at an outer end of the pivot hole 156. The combination of the spring 140, the ball 160, and the detent notches 164, 166, and 168 permits the tool bit-engaging member 22 to be pivoted with respect to the drive plate 152 in much the same way as it can be pivoted with respect to the drive plate 24 described previously. At each of the positions established by the detent notches 164, 166, 168, the ball 160 is urged into the respective notch by the spring 140, tending to retain the tool bit-engaging member 22 in that position of rotation with respect to the axis 170.
Furthermore, when the tool bit-engaging member 22 is in the in-line position shown in FIGS. 14 and 15, it can be moved axially toward the drive plate 152, thus moving the screw 106 within the pivot hole 156 while compressing the spring 140. As this occurs a receptacle in the form of a channel or groove portion 172 (partially defining the bore 142) defined in the top leg 102 of the base portion 100 of the tool bit-engaging member 22, passes over and receives the locking body 154 as indicated in FIGS. 15 and 16. With the locking body 154 thus located within the channel portion 172, as shown in FIG. 16, the locking body 154 cooperates with the spring-loaded detent ball 160 in the detent notch 164 and with the screw 106 located within the pivot hole 156 to prevent the tool bit-engaging member 22 from pivoting with respect to the drive plate 152, thus effectively preventing the tool bit-engaging member 22 from moving out of alignment with the drive plate 152 when the tool bit drive adaptor 150 is in use and sufficient axial pressure is applied through a tool bit to overcome the force of the spring 140.
The terms and expressions which have been employed in the foregoing specification are used therein as terms of description and not of limitation, and there is no intention, in the use of such terms and expressions, of excluding equivalents of the features shown and described or portions thereof, it being recognized that the scope of the invention is defined and limited only by the claims which follow. | An adaptor to mate with a hand tool such as a folding multipurpose tool to make use of the multipurpose tool as a handle to turn tool bits of various sizes, such as screwdrivers or small socket wrenches. The adaptor includes a drive plate which mates with the hand tool, and a tool bit-engaging member attached to the drive plate and movable angularly between various positions, with a latch to keep the tool bit-engaging member in a selected position. A pair of arms of the drive plate engage the sides of the jaws of one type of multipurpose tool to locate the adaptor as required with respect to the multipurpose tool. | 1 |
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