description stringlengths 2.98k 3.35M | abstract stringlengths 94 10.6k | cpc int64 0 8 |
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DESCRIPTION
[0001] The present invention concerns a method and a device for the positional correction of slab construction of precast concrete slabs, especially the slabs of a solid carriageway for high speed vehicles, whereby the precast concrete slabs are underset with a hard curing grout and are supported by a carrying layer of base fill.
[0002] Known concrete slab construction projects with precast concrete slabs are, among other applications, employed for existing carriageways for high speed traffic vehicles. The high speed vehicles are, in this present application, guided by rails. In order to achieve operation which is free of disturbance and comfortable on a high speed carriageway, it is necessary that the rails, and therewith the slabs of the slab construction be laid very exactly in regard to elevation and lateral dimensioning. The positional correction of the rails is done, normally, by means of known rail fastening systems as well as by means of interposing shims of different thicknesses underneath the rails. In this way, positional faults of the rail of the magnitude of about 30 mm can be compensated for. The disadvantage of this is, that greater corrections, which are frequently necessary when a subsidence of the base fill occurs, cannot be adjusted with such corrective measures, since such settling requires greater corrective movements.
[0003] Thus the purpose of the present invention is, to make possible a positional correction of a slab construction of precast concrete slabs, which permits a greater elevation correction.
[0004] This purpose is achieved by the features of the Claim 1 as well as the features of Claim 17.
[0005] In the method of the invention, a slab construction of precast concrete, especially of an existing carriageway for high speed vehicles, is corrected on site. The slab construction possesses two precast slabs bound to each other, wherein the precast slabs are set into a hard curing grout and are supported on a carrying layer base fill. For the positional correction of at least one precast slab, or a portion thereof, the said precast slab is entirely or partially released from its grout setting, and/or from its carrying layer, and is subsequently exactly realigned, and then the cut is refilled anew with undergrout. This method can well account for large corrections in elevation. The loosing, or releasing, can be carried out either by chemical or by mechanical means. The most advantageous method depends on the surrounding conditions and the materials of the grout.
[0006] If the substructure, especially the undergrout and/or the carrying layer, is cut through longitudinally and/or transversely, then in a very simple manner, the loosening of the precast slab can be carried out. The decision, as to whether the understructure should be cut in a longitudinal or a transverse direction, is dependent upon the kind of subsidence the slab has suffered, the correction tools which are available, and the conditions of the working environment.
[0007] If the grout material is cut through at (or near) the contact area of the precast plate, and/or the if it is the carrying layer which is cut through, then assurance can be made, that a satisfactory grout entry and strong binding of the new grout to the precast concrete slab will be made.
[0008] If, before the cutting of the understructure takes place, particularly that of the grout, a boring is made in the said understructure for the insertion of the cutting means, that being especially a saw blade, then it is not necessary to cut through the precast slab at the beginning of the separating cut of the understructure.
[0009] If the line of the cut shows a length, which is unequal to the length of the precast slab, and especially if said line does not begin or end at the contact point of two precast slabs, a possible weakness at the slab contact point is thereby avoided.
[0010] If, in the precast slab, grout feed openings are opened or created and used for fresh grout, then the filling of the new understructure grout is substantially eased. A filling of the grout which is essentially free of air inclusions is thus enabled.
[0011] It is especially of advantage, if, closed up openings for the old undergrout are opened and made use of for the new substrate grout.
[0012] If the precast slab can be exactly aligned with integrally placed mechanical or hydraulic lifting means already within said slab, for instance, spindles, then it often becomes possible, in a simple way, that these means, still available from the first alignment can aid in the present alignment of the precast slab.
[0013] In order to avoid damage to the spindles by cutting through the layer, it is of advantage, if the spindles are removed from the area of the separation before the through-cut and only replaced in their support position after the cut.
[0014] In order to restore travel operation as soon as possible on the precast concrete slab, it is of advantage, if the precast concrete slab is underlain with an especially fast-cure bitumen-cement mortar, plastic or cement mortar.
[0015] A device in accord with the invention exhibits a separation apparatus for the loosening, and especially for the through cutting of an understructure, particularly the grout, placed beneath a precast slab of a carriageway for track guided high speed vehicles.
[0016] The existing carriageway consists mainly of at least one set of a first and a second precast concrete slab bound together. The cutting device is placed on the precast slab to be loosened, or on an adjacently placed precast slab, or advantageously, on the rails.
[0017] A further invented apparatus possesses a separating device for the loosing of at least a part of a precast slab of an existing carriageway for rail guided high speed vehicles from its understructure. The separating device is on a guidance mechanism independent of the precast slab to be loosened, and is particularly well placed on the next rail. The existing carriageways are mostly laid in double-track manner, so that the separating device can be run on the next rail for the loosening of the required rail.
[0018] If the cutting device employs a self-moving power in the longitudinal direction of the precast concrete slab, then, by a fixed placement of an abutment for the cutting device, a relatively long track stretch can be cut.
[0019] Advantageously, the separating device and/or the assembly are guided on the rails. In this way, an exactly guided cut is possible.
[0020] If the cutting assembly is firmly affixed on the rails, in particular, clamped thereon, then a fast equipment relocation for the lengthening of the separation cut is possible.
[0021] Further advantages of the invention are described in the following embodiment examples. There is shown in:
[0022] [0022]FIG. 1 a plan view of a precast concrete slab,
[0023] [0023]FIG. 2 a cross-section through the construction of a placement of a precast concrete slab,
[0024] [0024]FIG. 3 a section through the undergrout,
[0025] [0025]FIG. 4 a view of the lifting of the precast concrete slab,
[0026] [0026]FIG. 5 the filling of the space between the lifted precast concrete slab and the carrier layer, and
[0027] [0027]FIG. 6 an embodiment example of a cable saw.
[0028] In FIG. 1 is presented a top view of a precast concrete slab 1 . The precast concrete slab 1 possesses a multiplicity of projections, upon which the rails 2 are fastened. The rail fastenings, which can be executed in numerous known ways, permit a certain adjustment of the said rails in the vertical and horizontal directions. Insofar these adjustment possibilities do not suffice, for instance, because of the subsidence of the substructure, it becomes necessary to upwardly adjust the precast concrete slab 1 itself. For this purpose, in the present embodiment, at six positions are placed spindles 7 , which serve for the adjustment of the slab 1 . The spindles 7 , which are provided on the ends of the slab 1 as well as in the middle thereof, by a more or less difficult turning of the spindles 7 a fine adjustment of the slab 1 is achieved. These spindles 7 , which normally are already installed at the setting of the slab 1 , obtain, by means of the present invention, a second purpose, namely, in that they enable the correction of the already set slab. The spindles are aligned as matching, oppositely situated pairs.
[0029] [0029]FIG. 2 presents a cross-section through a construction of the precast concrete slab 1 as well as showing the successive strata. The precast concrete slab 1 , surmounting an intermediate layer of undergrout 4 is to be found on a carrier layer 5 . The carrier layer 5 can be, for example, hydraulically bound or possibly an asphalt or another appropriate supporting layer. The grout 4 binds the precast concrete slab 1 tightly to the carrier layer 5 . A spindle 7 , which served for the alignment of the precast concrete slab 1 at the first setting of the same, is presented in a drawn down position, because it does not perform any load bearing function for the precast concrete slab 1 . The said spindle is placed in a recess in the undergrout, so that it will be of service in the future.
[0030] For the correction of the precast concrete slab 1 , in accord with FIG. 3, the undergrout layer 4 is shown as cut. By this means, the precast concrete slab 1 , after the undergrout 4 has been cut, is now vertically movable, within the framework of its connections in the slab construction. It is of exceptional value, if the cut in the undergrout 4 is made directly at the dividing plane to the precast concrete slab 1 . By this means, a higher quality binding of the new filling of undergrout, which is yet to be poured, with the precast concrete slab 1 is assured. The old connection layer of the undergrout 4 with the precast concrete slab 1 is, by this operation, relieved of its previous carrying function and is bound to the new layer. Advantageously, it is also possible to make the separating cut between the carrier layer 5 and the undergrout 4 . Even in this case, a possibly loose connection can be renewed. The separation at or in proximity to the connection location between the precast concrete slab 1 and the undergrout is, in any case, easier to carry out, since, when the known thickness of the precast concrete slab 1 is at hand, this location is more simply determined by means of an instrument and accordingly can be more exactly cut. Although the thickness of the undergrout 4 can vary, this connection location is simpler to capture than that of the connection plane of the hydraulically bound carrier layer 5 .
[0031] If the precast concrete slab 1 must be lowered, then a square cross-sectional block of the undergrout is cut out and subsequently the precast concrete slab 1 is allowed to drop into the opening thereby formed.
[0032] In FIG. 4, the lifting of the precast concrete slab 1 is shown. By the driving down of the spindle 7 , and the corresponding fine alignment of the precast concrete slab 1 , the said slab is raised away from the under support structure. The opening is, by this action, made larger.
[0033] In FIG. 5, the precast concrete slab 1 is newly under filled with grout. The undergrout is now in the cured state, so that the spindle can again be relieved of the load.
[0034] In FIG. 6 is shown in sketch form, the arrangement of the separating device on the precast concrete slab 1 . The separating device, which can be a cable saw, an oxygen lance, or other means, can be carried on a movable slider 21 . The slider 21 is drawn by means of a cable winch over the location at which the precast concrete slab 1 is to be cut. The winch, that is the cable, is anchored at a fixed abutment. Advantageously, this abutment can be placed on the adjacent precast concrete slab 1 . As a guide for the said slider 21 , this function can be fulfilled by setting the slider 21 on the rails which surmount the precast concrete slab 1 . Likewise, the rails 21 can serve for the fastening of the said abutment. The abutment, in this case, is advantageously clamped to the rails 21 and after the maximum travel of the slider 21 has been expended, then the abutment itself can be moved ahead for a renewal of the separating cut.
[0035] For a quicker cure of the new undergrout, especially in cold weather, it is advantageous if the undergrout or the separation opening is heated. In order to achieve a satisfactory connection to the new undergrout, in any case, it is of advantage if the opening is cleaned before the refill with a high pressure water stream. The separation opening can also extend into the carrier layer, if the new grout material is chosen to be compatible with the said carrier layer to make a good bonding.
[0036] The present invention can also be employed for the replacement of complete precast concrete slabs. The original slabs, in this case, are completely removed from the interconnected binding system and replaced by exchange slabs. | The invention relates to a method for correcting the position of a slab construction, especially a solid carriageway for high-speed vehicles, consisting of precast concrete slabs ( 1 ). The precast slabs ( 1 ) are supported by a substrate made from hardenable underpoured material ( 4 ) and a supporting layer ( 5 ) on the base. In order to correct the person of at least one precast slab ( 1 ), the precast slab ( 1 ) is at least partially detached from the substructure, especially from the under poured material ( 4 ) and/or the supporting layer ( 5 ), whereupon it is finely aligned and then underpoured once more with said material ( 4 ). A separating device ( 20.21 ) is arranged on a precast concrete slab ( 1 ) which is to be detached on a successive precast concrete slab in a device provided with one such separating device in order to detach at least one part of a concrete slab ( 1 ) pertaining to a solid carriageway for high speed vehicles from the substructure thereof, especially when the position is corrected. | 4 |
RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Application No. 61/334,089, filed on May 12, 2010, the disclosure of which is incorporated herein in its entirety.
BACKGROUND
[0002] 1. Field
[0003] One or more embodiments of the present invention relate to a battery pack, and more particularly, to a battery pack including a tab coupling a terminal of a first secondary battery to a terminal of a second secondary battery.
[0004] 2. Description of the Related Technology
[0005] Secondary batteries typically include lithium-based oxides as positive electrode active materials and carbonaceous materials as negative electrode active materials. In general, according to the type of electrolyte used, secondary batteries can be categorized into liquid electrolyte batteries and polymer electrolyte batteries. Batteries using a liquid electrolyte are called lithium ion batteries, and batteries using a polymer electrolyte are called lithium polymer batteries. In secondary batteries, a bare cell formed by sealing a can housing an electrode assembly and an electrolytic solution is typically electrically connected to a protection circuit substrate. The bare cell is typically electrically charged or discharged by a chemical reaction, and the protection circuit substrate typically protects the bare cell by preventing overcharge and over-discharge while controlling charge and discharge of the bare cell. The battery pack typically includes a plurality of secondary batteries arranged in series or parallel. In this regard, the secondary batteries may be electrically connected by a coupling tab or the like.
SUMMARY
[0006] One or more embodiments of the present invention relate to a battery pack, and more particularly, to a structure of a battery pack including a coupling tab.
[0007] According to an embodiment of the present invention, the battery pack comprises a plurality of secondary batteries, wherein each battery comprises a terminal; and a tab coupling a terminal of a first secondary battery to a terminal of a second secondary battery; wherein a first end of the tab comprises a first region having a first welding portion and a second region having a second welding portion, and wherein the first and second regions of the first end of the tab are separated by a first space.
[0008] According to another embodiment, a method of forming a battery pack comprises: providing a plurality of secondary batteries, wherein each battery comprises a terminal; and coupling a tab between a terminal of a first secondary battery and a terminal of a second secondary battery; wherein a first end of the tab comprises a first region having a first welding portion and a second region having a second welding portion, and wherein the first and second regions of the first end of the tab are separated by a first space.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is a schematic perspective view of a battery pack according to an embodiment of the present invention.
[0010] FIG. 2 is a partially exploded and enlarged perspective view of FIG. 1 .
[0011] FIG. 3 is a plan view of a coupling tab according to an embodiment of the present invention.
[0012] FIG. 4A is a schematic sectional view taken along a line 4 a - 4 a ′ of FIG. 3 .
[0013] FIG. 4B is a schematic sectional view taken along a line 4 b - 4 b ′ of FIG. 3 .
[0014] FIG. 5 is a schematic perspective view illustrating a relation between a coupling tab and welding rods.
[0015] FIG. 6 is a schematic sectional view illustrating a welding process in which a coupling tab is welded by welding rods.
[0016] FIG. 7A is a first modified example of an embodiment as illustrated in FIG. 4A .
[0017] FIG. 7B is a second modified example of an embodiment as illustrated in FIG. 4B .
[0018] FIG. 8 is a first modified example of an embodiment as illustrated in FIG. 2 .
DETAILED DESCRIPTION
[0019] Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings.
[0020] FIG. 1 is a schematic perspective view of a battery pack 1 according to an embodiment of the present invention. FIG. 2 is a partially exploded and enlarged perspective view of FIG. 1 .
[0021] According to an embodiment, the battery pack 1 includes a plurality of secondary batteries 10 and a case 100 . The secondary batteries 10 may form a rechargeable battery assembly. In this regard, each secondary battery 10 may be, for example, a nickel-cadmium (Ni—Cd) battery, a nickel-hydrogen (Ni—MH) battery, or a lithium (Li) secondary battery. Lithium ion secondary batteries typically have operation voltages about three times higher than those of nickel-cadmium batteries, which are generally used as power sources for portable electronic devices, and those of nickel-hydrogen batteries. Lithion ion secondary batteries generally have high energy density per unit weight and can therefore be widely used. An output current and an output voltage of a single secondary battery 10 may be increased by connecting a plurality of secondary batteries in series or parallel. In this regard, the shape of the secondary batteries 10 may be rectangular or cylindrical.
[0022] Referring to FIG. 2 , although the shape of the embodiment of the present invention is described as cylindrical secondary batteries, the shape of the secondary batteries 10 is not limited thereto. Each of secondary batteries 10 may include terminals 10 a and 10 b at both ends for electrical contacts to the external device. However, the location of the terminals 10 a and 10 b on the secondary battery may not be limited to the embodiments illustrated in FIG. 1 or 2 . For example, the cylindrical or rectangular secondary batteries 10 may include the terminals 10 a and 10 b on an end or a side surface thereof for an electric contact with the external device.
[0023] The disposition direction of the secondary battery 10 may vary. Referring to FIG. 1 , every four secondary batteries 10 are disposed in the same direction according to an embodiment. However, the disposition direction is not limited thereto. For example, the secondary batteries 10 may be disposed in alternative directions in every two or six secondary batteries.
[0024] The case 100 may include an upper case 100 A and a lower case 100 B. In this regard, the case 100 may accommodate the secondary batteries 10 therein or pull the secondary batteries 10 therefrom by coupling or separating of the upper case 100 A and the lower case 100 B as illustrated in FIG. 2 . The case 100 may include a material that does not conduct electricity, such as plastic. Alternatively, the case 100 may have a frame including metal such as aluminum, and a surface of the frame may be coated with a material that insulates electricity. In this regard, the upper case 100 A and the lower case 100 B may include plates 100 A 1 and 100 B 1 , side walls 100 A 2 and 100 B 2 , and guide rails 100 A 3 and 100 B 3 , respectively. In this regard, the plates 100 A 1 and 100 B 1 , the side walls 100 A 2 and 100 B 2 , and the guide rails 100 A 3 and 100 B 3 may be coupled together by a separable component or may be integrated to form one body. In this regard, the upper case 100 A and the lower case 100 B may be symmetrical to each other.
[0025] Referring to FIG. 2 , the plates 100 A 1 and 100 B 1 each have holes h according to an embodiment. In this regard, the hole h may be formed to corresponding with the ends of the secondary batteries 10 . Accordingly, the terminals 10 a and 10 b of each secondary battery 10 may be electrically connected through the holes h of the plates 100 A 1 and 100 B 1 with the external device. In addition, the secondary batteries 10 may be connected in series or parallel through the hole h.
[0026] As described above, the cases 100 A and 100 B respectively including the plates 100 A 1 and 100 B 1 , side walls 100 A 2 and 100 B 2 , and guide rails 100 A 3 and 100 B 3 may be coupled to the secondary batteries 10 . In addition, the coupled secondary batteries 10 may be connected to each other in series or parallel by connecting the coupling tab 200 to the terminals 10 a and 10 b of the secondary battery 10 . In this regard, the coupling tab 200 may be coupled to the terminals 10 a and 10 b of the secondary battery 10 by welding. For example, the coupling tab 200 may be coupled to the terminals 10 a and 10 b of the secondary battery 10 by resistance welding. The resistance welding may be performed by using, for example, a projection melding method. The projection welding may be, for example, performed in a way that the current passage is restricted by the shape of a structure of the parts being welded, such as an embossed shape.
[0027] FIG. 3 is a plan view of the coupling tab 200 according to an embodiment of the present invention. FIG. 4A is a schematic sectional view taken along a line 4 a - 4 a ′ of FIG. 3 . FIG. 4B is a schematic sectional view taken along a line 4 b - 4 b ′ of FIG. 3 . FIG. 5 is a schematic perspective view illustrating a relation between the coupling tab 200 and welding rods 300 and 310 . FIG. 6 is a schematic sectional view illustrating a welding process in which the coupling tab 200 is welded to the terminal 10 a of the secondary battery 10 using welding rods.
[0028] With respect to the welding process, a side surface of an embossing portion could be easily destroyed after the welding. When the side surface of the embossed portion is destroyed after welding, tension may be reduced although a nugget is formed. To solve this problem, according to an embodiment of the present invention, the coupling tab 200 can have a structure such that the strength of adherence between the coupling tab 200 and the terminals 10 a and 10 b may increase and destruction of the side surface of the embossed portion after welding may decrease. Referring to FIG. 3 , illustrating a plan view of the coupling tab 200 according to an embodiment of the present invention, the coupling tab 200 may have welding portions 210 that have an oval shape. One welding portion 210 and another welding portion 210 may be separated by a slit S. According to an embodiment of the present invention, the coupling tab 200 may have, for example, a letter ‘H’ shape as illustrated in FIG. 3 . Referring to FIG. 3 , the coupling tab 200 may include four welding portions 210 and a slit S may be formed between neighboring welding portions 210 .
[0029] The welding portion 210 may include a first plane 210 a and an inclined plane 210 b. A circumference of the welding portion 210 may have an oval shape in a plan view thereof, and the first plane 210 a inside the oval structure may be rectangular and may be formed inside the welding portion 210 . In this regard, ends of the welding rods 300 and 310 may contact the first plane 210 a of the coupling tab 200 , and the inclined plane 210 b can safely guide the welding rods 300 and 310 to the first plane 210 a.
[0030] The rectangular first plane 210 a can have a length of a first direction x and a length of a second direction y, respectively referred to as a and b. In this regard, the first plane 210 a can extend along the first direction x and thus have a degree of freedom so that the welding rods 300 and 310 contacting the first plane 210 a are moveable. If the first plane 210 a is quadrilateral or circular, the degree of freedom for movement of the welding rods 300 and 310 would be limited and thus automatic or manual movement of the welding rods 300 and 310 would require a higher level of control. If the welding rods 300 and 310 and the coupling tab 200 are misaligned or have contact errors with respect to each other, a side surface of an embossed portion could be destroyed. Accordingly, the extension of the first plane 210 a in the first direction x can allow for a higher degree of freedom of the welding rods 300 and 310 , and thus stability can be improved. For example, referring to FIG. 5 , the welding rods 300 and 310 can have a degree of freedom such that when the welding rod 300 contacts the coupling tab 200 , the welding rod 300 can move along the first direction x. Thus, even when the welding rods 300 and 310 are misaligned within the margins of error, structurally, the position error of the welding rods 300 and 310 may be controlled. In this regard, for example, a ratio of a, the length of the first plane 210 a in the first direction x to b, the length of the first plane 210 a in the second direction y may be in the range of about 1.5:1 to 3:1. For example, the ratio of a to b may be about 1.7:1.
[0031] In this regard, having the extension direction of the first plane 210 a in the first direction x may be advantageous compared to having the direction in the second direction y. This is because the distance t between the welding portion 210 and an edge of the coupling tab 200 should ensure a predetermined length or more for safety reasons. If the first plane 210 a extends in a direction of the second direction y, it may be difficult to retain t, the distance between the welding portion 210 and the edge of the coupling tab 200 , to be a predetermined value or more. Accordingly, the first plane 210 a may extend in the first direction x.
[0032] In addition, the first plane 210 a may be a plane having a straight line. When the first plane 210 a is a plane having a straight line, the ends of the welding rods 300 and 310 may properly contact the first plane 210 a. If the first plane 210 a is curved, the first plane 210 a and the welding rods 300 and 310 may have a contact error and thus a side surface of an embossed portion may be easily destroyed after welding. In this regard, a second surface 210 c of the coupling tab 200 disposed in an opposition direction (−z) to a third direction may also be a flat plane. Due to the flat plane surface of the second surface 210 c, it can be ensured that the coupling tab 200 contacts the terminals 10 a and 10 b of the secondary battery 10 . That is, the coupling tab 200 can contact the surface of the terminals 10 a and 10 b such that the coupling tab 200 does not slide with respect to the terminals 10 a and 10 b.
[0033] Hereinafter, a slit S formed between the welding portions 210 according to embodiments will be described in detail. Referring to FIG. 6 , the coupling tab 200 may contact the terminal 10 a, and electricity having a predetermined current and voltage is provided to the coupling tab 200 from the first welding rod 300 and the second welding rod 310 , thereby flowing a current from a first spot A 1 to second spot A 2 of the coupling tab 200 , that is, along passage A as shown in FIG. 6 . In this regard, heat may occur by resistance generated between the coupling tab 200 and the terminal 10 a, and thus welding can be performed. If the slit S is not formed, a current can flow from the first spot A 1 to the second spot A 2 , that is, an opposition direction (−y) of the second direction, and the flowing current may be a wattless current that does not affect welding. Since a space may be formed between the first spot A 1 and the second spot A 2 by the slit S and thus a current can flow along passage A, a wattless current may be decreased due to the slit S. In addition, referring to FIG. 3 , the slit S may be formed to extend in the first direction x, and thus, passage B may be formed to be longer than passage A, thereby inducing a current to flow along passage A, not passage B. That is, since a current is likely to flow along a shorter passage and the B passage extends in the first direction x by the slit S, a current at the first spot A 1 may be induced to flow through passage A, not passage B. In this regard, in FIG. 3 , a ratio of a width c of the slit S to a distance d between a center of the welding portion 210 and a split point of the slit S may be in the range of about 1:3 to 1:10, for example, about 1:6.5. However, the ratio of c:d may not be limited thereto.
[0034] Accordingly, wattless currents flowing in other directions can be reduced and thus more current can flow along the passage A. Since a large amount of current flows along passage A, an electric resistance between the welding portion 210 and the terminal 10 a can be increased and more heat can be generated. In this regard, a welding clump formed by fusing the welding portion 210 with the terminal 10 a by heat dissipation, that is, a large welding nugget can be formed. In this regard, the amount of heat of the welding portion 210 may be proportional to a square of the current flowing from the welding rods 300 and 310 . Accordingly, since the coupling tab 200 may be welded to the terminal 10 a by a large welding nugget with a high welding strength, the coupling tab 200 may be more strongly welded to the terminal 10 a.
[0035] In this regard, the coupling tab 200 may be formed of, for example, a conductive metal including any one kind of metal or a plurality of metals selected from the group consisting of nickel, nickel alloy, iron, iron alloy, stainless, zinc, zinc alloy, copper, copper alloy, silver, silver alloy, gold, gold alloy, platinum, platinum alloy, aluminum, aluminum alloy, molybdenum, molybdenum alloy, tungsten, tungsten alloy, titanium, titanium alloy, beryllium, berylium alloy, rhodium, and rhodium alloy.
[0036] With reference to FIG. 7A or 7 B, modified examples of an embodiment of the present invention will be described in detail. FIG. 7A is a first modified example of the embodiment illustrated in FIG. 4A , and FIG. 7B is a second modified example of the embodiment illustrated in FIG. 4B . Referring to FIG. 7A or 7 B, the welding portion 210 may include the first plane 210 a and the inclined surface 210 b, and the third surface 210 d disposed in an opposition direction (−z) to the third direction of the coupling tab 200 . The third surface 210 d may be curved. In this regard, when the curved third surface 210 d is welded to the terminal 10 a by a resistance, the third surface 210 d may have a planar shape corresponding to the shape of the terminal 10 a.
[0037] Although the coupling tab 200 having a letter ‘H’ shape is illustrated in FIG. 3 , the shape of the coupling tab 200 is not limited thereto. For example, two coupling tabs 200 may be connected to each other by a connection portion C. FIG. 8 is a first modified example of the embodiment illustrated in FIG. 2 . In this regard, the coupling tab 200 may have various shapes according to the number and arrangement of the secondary batteries 10 included in a battery pack ( 1 ), and the coupling tab 200 may be welded to the secondary battery 10 through various numbers of the welding portions 210 , and the location of the welding portions of the coupling tab 200 may vary.
[0038] During welding, the welding current amount, current flowing time, and a pressure between the welding rods 300 and 310 and the coupling tab 200 may be variously controlled.
[0039] It should be understood that certain embodiments described therein should be considered in a descriptive sense only and not for purposes of limitation. Descriptions of features or aspects within each embodiment should typically be considered as available for other similar features or aspects in other embodiments. | A battery pack comprises: a plurality of secondary batteries, wherein each battery comprises a terminal; and a tab coupling a terminal of a first secondary battery to a terminal of a second secondary battery; wherein a first end of the tab comprises a first region having a first welding portion and a second region having a second welding portion, and wherein the first and second regions of the first end of the tab are separated by a first space. | 8 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Patent application Ser. No. 61/026,402 filed Feb. 5, 2008; the disclosures of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Technical Field
[0003] The present invention relates generally to media storage containers and, more particularly, to media storage containers adapted to store and display one or more disc-shaped items of recorded media. Specifically, the invention relates to a paper-based media disc storage container having one or more disc pockets that are loaded by sliding the discs through slots defined at an edge or edges of the container. Shoulders disposed at the neck of each pocket retain the disc in the pocket in a loose, unstressed condition. The containers are assembled by folding a plurality of panels in a manner that provides smooth exposed edges to the user of the container.
[0004] 2. Background Information
[0005] Various media disc storage containers are known in the art. Some of the most common storage containers for recorded media are plastic book-like containers having a lid connected to a base with a hinge. In most plastic containers and some containers made from recycled paper, the media disc is held by a hub in the base of the container. In other containers, the disc is disposed in a close-fitting storage chamber that is defined between a base and a lid that is hinged to the base in a clamshell fashion. The disc is removable when the lid is opened.
[0006] Some retailers and customers desire a media storage container manufactured entirely from recycled paper and recyclable paper. Many of these paper-based containers are used as disc mailers. One problem common to these paper-based containers is the need to retain the disc within the container. Another problem is the need to easily load and unload the disc from the container. One type of paper-based media disc storage container is in the form of an envelope where the top of the envelope is closed with a fold-over flap. This flap must be pivoted open in order to remove the disc from the container. Another type of paper-based media disc storage container is in the form of an envelope that allows the disc to freely slip out of the envelope. These containers are undesirable because the user can easily drop the disc from the container causing damage to the disc. U.S. Pat. Nos. 5,096,064 and 5,422,875 disclose arrangements that prevent a disc from readily falling out of an enclosure. Those who package media disc desire unique packaging configurations that securely hold media discs while providing interesting presentations of the media discs to the users. Large uninterrupted smooth surfaces are desired for graphics and information related to the media disc.
BRIEF SUMMARY OF THE INVENTION
[0007] The invention provides a media storage container having a sleeve defining a media disc holding pocket that holds the disc in an unstressed configuration. Compressible shoulders disposed at the neck of the pocket retain the media disc within the pocket.
[0008] In one configuration, the container has a base that defines the pocket and a cover that pivots between open and closed configurations. The media disc is loaded and unloaded through an opening in the top of the base. The base may optionally define a window that allows one or both of the major disc surfaces to be viewed and engaged by the user's finger without allowing the disc to be removed through the window.
[0009] In other configurations, the pocket is loaded through an opening defined by the sidewall, or the bottom wall of the base.
[0010] In other configurations, the pocket or an additional pocket may be defined by the cover.
[0011] In other configurations, multiple pockets may be defined by the base or cover so that the container may hold multiple discs.
[0012] These configurations may be fabricated from a single blank that is folded about living hinges and secured together with adhesive or other connectors.
[0013] Other configurations of the media disc container may include a pocket that slides between extended and retracted positions within an outer sleeve.
[0014] The configurations described above may be formed with smooth outer edges to provide an attractive appearance and a desirable feel to the container. The smooth outer edges also help the pocket from delaminating.
[0015] These configurations are provided individually and in combination with one another to form additional configurations. Examples of the invention are described below.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0016] FIG. 1 is a perspective view of a first configuration of a media disc storage container with the cover mostly closed over the inner surface of the base.
[0017] FIG. 2 is a perspective view of the media disc storage container with the cover open.
[0018] FIG. 3 is a view similar to FIG. 2 showing a media disc being inserted through the opening into the pocket.
[0019] FIG. 4 is a view similar to FIG. 3 showing the inner panel of the base removed with the media disc about to engage the shoulders of the intermediate base panels.
[0020] FIG. 5 is a view similar to FIG. 4 showing the media disc disposed in the pocket under the shoulders.
[0021] FIG. 6 is a top plan view of a blank that may be folded into the container configuration of FIG. 1 .
[0022] FIG. 7 is a perspective view of a second configuration of a media disc storage container with the cover mostly closed over the inner surface of the base.
[0023] FIG. 8 is a perspective view of the media disc storage container with the cover open.
[0024] FIG. 9 is a view similar to FIG. 8 showing a media disc being inserted through the opening into the pocket.
[0025] FIG. 10 is a view similar to FIG. 9 showing the inner panel of the base removed with the media disc about to engage the shoulders of the intermediate base panels.
[0026] FIG. 11 is a view similar to FIG. 10 showing the media disc disposed in the pocket under the shoulders.
[0027] FIG. 12 is a top plan view of a blank that may be folded into the container configuration of FIG. 7 .
[0028] FIG. 13 is a perspective view of a third configuration of a media disc storage container with the cover mostly closed over the inner surface of the base.
[0029] FIG. 14 is a perspective view of the media disc storage container with the cover open.
[0030] FIG. 15 is a view similar to FIG. 14 showing two media discs being inserted through the openings into the pockets.
[0031] FIG. 16 is a view similar to FIG. 15 showing the inner panels of the cover and base removed with the media disc about to engage the shoulders of the intermediate panels.
[0032] FIG. 17 is a view similar to FIG. 16 showing the media discs disposed in the pockets under the shoulders.
[0033] FIG. 18 is a top plan view of a blank that may be folded into the container configuration of FIG. 13 .
[0034] FIG. 19 is a perspective view of a fourth configuration of the media disc storage container showing a disc holding base disposed in its retracted position with respective to an outer sleeve.
[0035] FIG. 20 is a perspective view of the fourth configuration with the base in its extended position.
[0036] FIG. 21 is a view similar to FIG. 20 showing a media disc being inserted through the opening into the pocket.
[0037] FIG. 22 is a view similar to FIG. 21 showing the inner panel of the base removed with the media disc about to engage the shoulders of the intermediate base panels.
[0038] FIG. 23 is a view similar to FIG. 22 showing the media disc disposed in the pocket under the shoulders.
[0039] FIG. 24A is a top plan view of a blank that may be folded into the sleeve for the fourth configuration of the container.
[0040] FIG. 24B is a top plan view of a blank that may be folded into the base for the fourth configuration of the container.
[0041] FIG. 25 is a perspective view of a fifth configuration of the media disc storage container showing a disc holding base disposed in its retracted position with respective to an outer sleeve.
[0042] FIG. 26 is a perspective view of the fifth configuration with the base in its extended position.
[0043] FIG. 27 is a view similar to FIG. 26 showing two media discs being inserted through the openings into the pockets.
[0044] FIG. 28 is a view similar to FIG. 27 showing the inner panel of the base removed with the media disc about to engage the shoulders of the intermediate base panels.
[0045] FIG. 29 is a view similar to FIG. 28 showing the media disc disposed in the pocket under the shoulders.
[0046] FIG. 30A is a top plan view of a blank that may be folded into the sleeve for the fourth configuration of the container.
[0047] FIG. 30B is a top plan view of a blank that may be folded into the base for the fourth configuration of the container.
[0048] Similar numbers refer to similar parts throughout the specification.
DETAILED DESCRIPTION OF THE INVENTION
[0049] First, second, and third configurations of the media disc storage container are indicated generally by the numeral 2 in the FIGS. 1-18 . Container configurations 2 generally include a base 4 and a cover 6 connected to base 4 by a hinge wall 8 and a pair of living hinges 10 . Cover 6 moves between open and closed positions with respect to base 4 by pivoting about hinges 10 . In these exemplary configurations, container 2 defines a pocket 12 that is configured to hold at least one disc-shaped item of recorded media 14 such as a DVD or a CD. Container 2 may be manufactured from a paperboard material having a smooth outer surface. The paperboard may have a core sandwiched between a pair of smooth outer liners.
[0050] Base 4 includes an inner panel 20 , first 22 and second 24 intermediate panels, and an outer panel 26 . In alternative configurations, first 22 and second 24 intermediate panels may be provided as a single intermediate panel. In the exemplary configuration, inner panel 20 defines a window 28 that allows a portion of disc 14 to be viewed when cover 6 is open. Disc 14 may not be removed through window 28 . If desired, outer panel 26 also may define a similar window.
[0051] Intermediate panels 22 and 24 define pocket 12 and the opening 30 through which disc 14 is loaded into and unloaded from container 2 . Opening 30 may be disposed at the top wall of container 2 as shown in the first configuration or at the sidewall as shown in the second and third configurations. Opening 30 also may be disposed in the bottom wall opposite the top wall or a pair of openings 30 may be provided to allow the media disc to be loaded and unloaded from different sides. Pocket 12 is generally U-shaped. Pocket 12 includes a semi-circular bottom portion and an elongated channel portion. Opposed compressible shoulders 34 are disposed at the end of the channel portion to define a neck that separates the bottom portion from the channel portion. Pocket 12 is configured to hold disc 14 in an unstressed configuration such that disc 14 is not pinched.
[0052] Shoulders 34 are configured to prevent disc 14 from readily falling out of container 2 . Shoulders 34 are spaced apart a distance that is substantially equal to or slightly less than the outer diameter of disc 14 such that disc 14 frictionally engages shoulders 34 when disc 14 is first loaded into container 2 . Shoulders 34 are tapered on both the pocket side and the opening side with the peak being rounded. The inward pocket side of each shoulder 34 may be a continuation of the round bottom of pocket 12 having the same diameter as the bottom of pocket 12 . Shoulders 34 thus do not pinch disc 14 when disc 14 is disposed in pocket 12 . The portions of intermediate panels 22 and 24 that form shoulders 34 may be adhered together while shoulders 34 may not be adhered to panels 20 and 26 . Shoulders 34 are thus free to be compressed between panels 20 and 26 when disc 14 is pushed between shoulders 34 . The loading of disc 14 slightly deforms or compresses at least one of shoulders 34 as disc 14 passes between shoulders 34 . Once disc 14 is loaded, shoulders 34 resiliently return to some degree back toward their original form to retain disc 14 in pocket 12 . Because shoulders 34 are made from the paper-based material of panels 22 and 24 , they are not fully resilient when compressed, but will resiliently rebound from a compressed condition to function again. In one configuration, only one of intermediate panels 22 and 24 has shoulders 34 . This makes shoulder 34 thinner and easier to compress.
[0053] The bottom of pocket 12 is circular and has a diameter slightly larger than disc 14 so that disc 14 is evenly seated against the bottom of pocket 12 when disc 14 is disposed in pocket. Opening 30 is slightly wider than the diameter of disc 30 .
[0054] Base 4 is formed by folding intermediate panels 22 and 24 onto the inner surfaces of panels 20 and 26 about hinges 40 . Hinge 40 is formed by indenting the material between the panels. In the first configuration, the outer surfaces of the paperboard of hinges 40 are not cut so that the outer surface of the paperboard liner remains intact to provide a pair of stacked smooth rounded edges 46 along the side of container 2 . The major portions of panels 22 and 24 may be directly adhered to panels 20 and 26 . Panels 20 and 22 are then folded about hinge 42 onto panels 24 and 26 to form base 4 . Hinge 42 is formed to provide a smooth rounded edge 44 on each side of opening 30 for the comfort and safety of the user. The outer liner of hinge 42 remains intact when the fold is formed to form edge 44 . When two intermediate layers are used, base 4 is defined by four thicknesses of material. Each panel may have a thickness that is slightly greater than half the thickness of disc 14 such that pocket 12 has a depth slightly greater than the thickness of disc 14 . Disc 14 may thus freely rotate within pocket 12 and is not pinched or stressed while disc 14 is disposed in pocket 12 .
[0055] Cover 6 of the first and second configurations is defined by three thickness of material. Container 2 thus has at least seven layers of thickness when closed and is rigid enough to protect disc 14 if processed through the US mail. In the first and second configurations, cover 6 has an intermediate panel 50 that is folded down about hinge 51 against the inner surface of an outer panel 52 . The outer surface of hinge 51 is not broken to provide a smooth edge 53 to container 2 . An edge flap 54 is also folded over against the inner surface of outer panel 52 to define a smooth edge 56 for cover 6 . Edge flap 54 is not adhered to the inner surface of panel 52 . A booklet flap 58 is folded up about hinge 59 over the outer surface of intermediate panel 50 and the outer surface of edge flap 54 . The outer surface of hinge 59 is not broken to provide a smooth edge 61 to container 2 . The inner surface of the outer edge 60 of booklet flap 58 is adhered to the outer surface of edge flap 54 to define an open pocket to hold a literature booklet 62 related to disc 14 . Edge flap 54 may extend along the entire length of panel 52 to provide smooth edge 60 to the entire length of cover 6 .
[0056] Panel 20 may define a finger access cutout 64 that allows the user to grip the top of disc 14 when disc 14 is loaded in pocket 12 .
[0057] In the third configuration of container 2 shown in FIGS. 13-18 , the cover has a configuration that mirrors base 4 . The third configuration of container 2 provides a pair of pockets 12 accessible from the sides of container 2 . The reference numerals used to describe base 4 above are used to describe the elements of the cover in the third configuration. The third configuration also may be configured to provide access through the top of container 2 similar to the configuration of FIGS. 1-6 . In this configuration, booklet 62 may be loosely disposed between base 4 and cover 6 .
[0058] Fourth and fifth configurations of the media disc storage container are indicated generally by the numeral 102 in the FIGS. 19-30 . Container configurations 102 generally include a base 4 that is movable between retracted and extended positions with respect to an outer sleeve 106 . In order to prevent base 4 from falling out of sleeve 106 , base 4 includes a lock flange 110 that slides under a corresponding lock flange 112 disposed in sleeve 106 when base 4 is moved to the extended position. Lock flanges 110 and 112 are cantilevered so that they may freely engage. In these exemplary configurations, container 102 defines one or more pockets 12 that are each configured to hold at least one disc-shaped item of recorded media 14 such as a DVD or a CD.
[0059] In the fourth configuration of FIGS. 19-24 , base 4 is similar to base 4 of the second configuration with the addition of flange 110 . In the fifth configuration, base 4 is similar to the combined base and cover (two connected bases 4 ) of the third configuration with the exception being that windows 28 are defined by the outer panels 26 . In this configuration, the outer surfaces of panels 20 may be adhered together.
[0060] In both of the fourth and fifth configurations, bases 4 may be moved to their retracted positions to allow the user to view the outer surfaces of bases 4 and to view a portion of disc 14 before removing discs 14 from bases 4 . In each of these configurations, the outwardly disposed sidewall of base 4 is provided with smooth edges 44 .
[0061] Certain terms have been used for brevity, clearness, and understanding. No unnecessary limitations are to be implied therefrom beyond the requirement of the prior art because such terms are used for descriptive purposes and are intended to be broadly construed.
[0062] Moreover, the description and illustration of the invention are exemplary and the invention is not limited to the exact details shown or described. | A media storage container has a sleeve defining a media disc holding pocket that holds the disc in an unstressed configuration. Compressible shoulders disposed at the neck of the pocket retain the media disc within the pocket. In one configuration, the container has a base that defines the pocket and a cover that pivots between open and closed configurations. In other configurations, the base having the disc pocket is carried within a sleeve. The media disc may be loaded and unloaded through an opening in the top or the side of the base. The base may optionally define a window that allows one or both of the major disc surfaces to be viewed and engaged by the user's finger without allowing the disc to be removed through the window. | 6 |
BACKGROUND OF THE INVENTION
The present invention relates in general to computer aided design (CAD) tools used in design and development of electronic circuits and systems, and in particular to a synthesis technique that automatically derives optimum termination schemes for interconnects in such systems.
A common problem in electronic circuits is signal distortion caused by improperly terminated transmission lines or long interconnects. Termination refers to insertion of impedance along a transmission line whose value is adjusted to match the effective impedance of the driver and the transmission line. Without such matching impedance, the signal travelling the length of the interconnect experiences "reflection" (i.e., bouncing back along the interconnect line in the form of a return signal). Reflection causes undesired signal oscillation and, under severe conditions, may result in excessive delays and false logic switching. The problem is more acute in the case of high speed and high performance systems, where interconnect and delays associated with them play a more critical role in the overall system performance.
Properly terminated interconnects are therefore critical in order to minimize signal distortion and improve high frequency performance. Determining the required termination, however, is usually not a trivial task and often involves exhaustive trial and error simulations, specially for more complex circuits. The process typically involves an initial step of determining whether termination is required at all. Circuit functionality is simulated to analyze whether, for example, undershoot constraints are violated. Based on the results of the simulated distortion and noise levels, a specific type of termination may be selected from two general classes of terminations. These are shunt and series terminations.
Next, the proper location for inserting the termination must be identified. This is the most intractable step in the process since it depends on numerous factors and requires expert knowledge and exhaustive simulations. For critical circuits, deciding on the location of termination becomes a highly sophisticated art and is usually performed manually by skilled designers. For even moderately complex circuits, a considerable amount of time and effort is thus consumed by the process of defining a termination scheme. In the case of shunt terminations the problem of deciding on the number of terminations and locating them is particularly acute. Moreover, for more complex designs with thousands of devices and interconnects, manually developing termination schemes to control distortion is practically impossible.
There is therefore a need for improved methods of determining termination schemes for more complex and high speed circuits and systems.
SUMMARY OF THE INVENTION
The present invention provides an automated method of deriving an optimum termination scheme to minimize distortion and noise in electronic circuits and systems. According to one embodiment, the invention provides a method of deriving a termination scheme for a circuit, which includes machine executed steps of: (a) examining circuit performance to determine whether termination is required; (b) determining a termination type and value; (c) deriving an optimum location for the termination; (d) inserting the termination and verifying effect of termination; and (e) repeating steps (a) through (d) until circuit termination requirements are met.
In a more specific embodiment of the present invention the step of determining a termination type and value includes a further step of (f) deriving circuit electrical characteristics including driver types and slew rates, and interconnect load impedances and delays. Further, the step of deriving an optimum location for the termination includes an additional step of (g) adaptive partitioning of the circuit into clusters of load circuits.
A better understanding of the nature and advantages of the present invention may be had with reference to the detailed description and the accompanying drawings below.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows an exemplary CAD workstation wherein the termination synthesizer according to the present invention resides;
FIG. 2 is a flow diagram illustrating at a high level the termination synthesis method of the present invention;
FIG. 3 is a flow diagram showing a method for determining an optimum location for installing termination; and
FIGS. 4A and 4B illustrate the adaptive partitioning of technique of the present invention with an exemplary circuit.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The method and technique of the present invention is implemented within a CAD environment and typically resides inside a computer workstation used by design engineers. FIG. 1 shows a typical example of a computer workstation which houses various CAD modules such as circuit simulation and layout tools and the like. The workstation includes monitor 100, keyboard 102, cabinet 104 and mouse 106. Cabinet 104 houses a CD-ROM drive 108 or a hard drive (not shown) which may be utilized to store and retrieve CAD tools incorporating the present invention, digital images for use with the present invention, and the like. Although a CD-ROM 108 is shown as the removable media, other removable tangible media including floppy disks, tape, and flash memory may be utilized. Cabinet 104 also houses familiar computer components (not shown) such as a processor, memory, and various support network elements that execute CAD tools such as the termination synthesis module of the present invention. The computer workstation shown in FIG. 1 is but an example of a computer system suitable for use with the present invention. Other configurations of subsystems suitable for use with the present invention will be readily apparent to one of ordinary skill in the art.
FIG. 2 is a flow diagram illustrating at a high level the termination synthesis technique according to the present invention. The circuit performance is first analyzed (step 200) to determine distortion levels. This is accomplished by computer simulation of circuit functionality to observe signal behavior at various critical nodes within the circuit. A typical parameter that indicates the level of distortion is signal undershoot (or overshoot). If any signal exhibits distortion levels above an acceptable threshold level (i.e., undershoot constraint violated), the method of the invention initially assumes that there exist interconnect lines that are not properly terminated.
With an initial determination that termination is required, a terminator type and value is next selected (step 204). The types of terminators available are, for example, series (R1), shunt (R1, V1), thevenin (R1, V1, R2, V2), shunt RC (R1, C1, V1), clamp (V cutoff1 , V1), or dual clamp (V cutoff1 , V1, V cutoff2 , V2). A preferred embodiment of the termination synthesizer of the present invention provides the optional parameters inside the parenthesis, where R1 and R2 are resistor values, V1 and V2 are termination voltages, C1 is the capacitance, and V cutoff1 and V cutoff2 are the diode low and diode high cutoff voltages, respectively. The user has the option of either invoking the synthesizer with termination type and value specified, or with type only or with type and all or some of the terminator values specified. Terminator type and value are otherwise automatically derived by the synthesizer.
Determining the type of terminator involves an examination of the type of circuit that drives the signal over the critical interconnect line. The synthesizer examines the circuit and if it finds the driver circuit to be of an open type (e.g., open-collector as in emitter-coupled logic, ECL, or open-drain), it automatically inserts a DC shunt or DC thevenin terminator. If the circuit is not open and the type of terminator is not specified, then a default series type terminator is chosen.
In the absence of user-specified values, the synthesizer then automatically derives values for the terminator parameters based on the type of terminator. In the case of shunt or thevenin terminators, for example, the value of the terminator voltages are obtained by examining the drivers in the circuit. The value of the terminator resistors are approximated as the average transmission line impedance in the circuit. In the case of series termination resistors the value is given by R=Zo-Rs, where Zo is the average transmission line impedance of the circuit and Rs is the characteristic source impedance of the fastest driver in the circuit. It is based on the circuit behavioral models that the synthesizer predicts the operating impedances for the source and the load.
Once the termination type and value are derived, the synthesizer must determine the optimum location to insert the termination (step 206). According to a preferred embodiment of this invention, this step involves a complex adaptive partitioning of the circuit into clustered networks each requiring a separate termination. This step is described in greater detail hereinafter in connection with FIGS. 3, 4A and 4B. In the case of a smaller circuit, the synthesizer may determine that a location is not available (i.e., no clusters identified). Under such conditions the synthesizer concludes that the measured noise or distortion levels are not due to lack of termination and ends the process.
If the synthesizer identifies one or more clusters, the termination as defined in the preceding steps is inserted at the identified location (step 208). Next, the effectiveness of the added termination is verified by analyzing circuit performance once again (step 210) to check for constraint violations. If simulation results indicate that distortion has not been reduced, the synthesizer concludes that the measured distortion is not caused by improper termination, removes the termination and exits the program. If a reduction in distortion level is realized, however, the synthesizer repeats the process for additional terminators until the distortion level drops below the predetermined threshold level.
An important aspect of the termination synthesis technique of the present invention is the process of determining the optimum location for terminators. FIG. 3 is a flow diagram illustrating the process of termination location according to the present invention. In the case of series type terminators, the location is readily defined at the driver node (steps 302 and 304). Similarly, the location for a clamp or dual clamp terminator is readily defined at the receiver/load end (steps 306 and 308). For the remaining group of terminator types, namely shunt, shunt RC, thevenin, and the like, an adaptive partitioning technique is used to accurately locate the termination within the circuit.
The key factors to be considered in deciding on a location for the termination are driver switching speed and delay through the load circuit. The adaptive partitioning technique of the present invention divides the circuit into a number of clusters of components, with each cluster defined by a delay parameter. The delay parameter is based on the slew rate (i.e., switching speed) of the fastest driver. Accordingly, for this group of terminator types, the method of this invention first measures the driver slew rate (step 310). Next, the clustering delay parameter, referred to herein as the maximum stub delay, or MSD, is computed based on the driver slew rate (step 312). The MSD is set at a small fraction, for example 1/20, of the driver slew rate. A cluster is then defined as that part of the circuit that has a delay equal to the MSD.
After computing the MSD, a delay ordered list of terminus nodes with the farthest node being the first in the list is generated (step 314). Then, starting from the farthest node that is available for clustering (step 316), delay is measured as circuit components are added one at a time (step 318). The node at which the measured delay equals the MSD is designated as the cluster boundary, and is added to the list of clustered nodes (steps 320 and 322). The list of clustered nodes identifies the nodes where a terminator is installed. If there remain other components and nodes within the circuit this process continues (step 324) until the entire circuit is divided into one or more clusters identified by a list of clustered nodes.
This adaptive partitioning or clustering process is depicted by the exemplary circuit of FIGS. 4A and 4B, which are shown herein for illustrative purposes only. Referring to FIG. 4A there is shown an exemplary driver 400 driving a load circuit that includes a network of components 402. In this example, the load circuit is divided by the synthesis process into three clusters 404-1, 404-2, and 404-3. Each cluster 404 exhibits a delay equal to the measured maximum stub delay, and can be separately terminated. Terminations 406-1, 406-2, and 406-3 are then installed at the terminus node of each driver as shown. The selection of the type of termination is described as above.
Thus, the termination synthesis technique of the present invention provides an automated method of deriving optimum termination schemes for electronic circuits regardless of their size and complexity. While the above is a complete description of a specific embodiment of the present invention, it is possible to use various alternatives, modifications and equivalents. For example, options can be provided to allow the user to specify and thus override types of terminations or values for terminator elements at any stage of the synthesis process. The scope of the present invention should therefore not be determined with reference to the above description, but should instead, be determined with reference to the appended claims along with their full scope of equivalents. | A termination synthesis technique that automatically derives an optimum termination scheme for interconnects in electronic circuits. The termination synthesis technique uses an adaptive partitioning approach to divide a large circuit into separate clusters that can be independently terminated. The technique can thus automatically derive the optimum termination type and location for large and complex circuits. | 6 |
CROSS REFERENCE TO RELATED APPLICATIONS
This is a continuation of PCT application No. PCT/EP2008/063365, entitled “TRANSPORT BELT AND METHOD FOR THE PRODUCTION THEREOF”, filed Oct. 7, 2008, which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a belt for a machine for the production and treatment of a fibrous web, in particular a paper, cardboard or tissue machine, as well as to a method to manufacture said belt.
2. Description of the Related Art
Belts are used in machinery for the production and treatment of a fibrous web for example in the press section in order to transport the fibrous web through the press nip and subsequently to a transfer location where the fibrous web is transferred to the following dryer section.
Belts generally comprise at least one polymer coating providing the paper side of the belt into which a load-bearing textile fabric is embedded.
The known transport- or process belts often tend to delaminate during operation. The polymer coating which extends from the paper side to the machine side of the belt was applied from both sides of the textile fabric which therefore has an interior interface at which the polymer coatings separate during operation due to flexing.
In addition, the known transport- and process belts have several coating segments arranged adjacent to each other in cross machine direction, each of which represent only a partial width of the total polymer coating and which together form the polymer coating. The hitherto known transport- or process belts often break at the contact points of the coating segments.
In view of the aforementioned disadvantages, what is needed in the art is improved belts, as well as improved methods for their manufacture.
SUMMARY OF THE INVENTION
According to a first aspect of the invention, the present invention provides a transport- or process belt for a machine for the production or treatment of a fibrous web, especially a paper, cardboard or tissue machine, which has a paper side and a machine side, as well as a polymer coating and which includes a load-bearing textile fabric; whereby the textile fabric has a first side facing the paper side and a second side facing the machine side; whereby the textile fabric is permeable and has a permeability of at least 300 cfm, preferably of at least 550 cfm, and the polymer coating extends integrally from the first side of the textile fabric through the openings in the textile fabric to the second side of the textile fabric.
Based on the fact that the textile fabric has a permeability of at least 300 cfm, a polymer coating extending integrally from the first side of the textile fabric through the openings of the textile fabric to the second side of the textile fabric can be formed. Therefore, delamination of the polymer coating is almost impossible. Integrally in this context is to be understood that, viewed in thickness direction of the polymer coating, no interface exists inside the polymer coating extending from the first side to the second side of the textile fabric as could for example develop if the polymer material is applied onto the textile fabric from both sides and then meeting somewhere inside the textile fabric structure, thus forming an interface.
According to a second aspect of the invention, the present invention provides a method for the manufacture of a transport or process belt for a machine for the production or treatment of a fibrous web, in particular a paper, cardboard or tissue machine, with a textile fabric and a polymer coating comprising the following steps:
a) Providing a textile and permeable fabric which, viewed in the designated cross machine direction of the belt has a defined width as well as a first side facing the provided paper side of the belt and a second side facing the provided machine side of the belt; b) Coating of the permeable textile fabric on a partial width with polymer material in a viscous state in order to provide a first formed coating segment; c) Coating of the permeable textile fabric on a partial width with polymer material in a viscous state in order to provide a subsequently formed coating segment which overlaps the initially formed coating segment in certain areas in machine cross direction; d) Causing a bond of the two coating segments in the overlap area; e) Converting the polymer material from the viscous state to a solid state.
By providing an overlap area of adjacent coating segments, their bond with each other is clearly improved.
According to a third and alternative and/or additional aspect of the invention, the present invention provides a method for the manufacture of a transport or process belt for a machine for the production or treatment of a fibrous web, in particular a paper, cardboard or tissue machine, comprising the following steps:
a) Providing a permeable textile fabric with a first and a second longitudinal edge, respectively extending in the designated machine direction of the belt; b) Coating of the textile fabric with polymer material in a viscous state by means of a coating apparatus, whereby only a partial width of the textile fabric is coated simultaneously with the viscous polymer material by means of the coating apparatus; c) Converting the polymer material from the viscous to a solid state, whereby the textile fabric is a continuous belt and the continuous textile fabric is moved in the designated machine direction of the belt and the coating apparatus is moved in the designated cross machine direction of the belt relative to each other so that after movement of the coating apparatus from the first to the second longitudinal edge of the textile fabric the polymer material which was applied onto the textile fabric in a helix-type path forms a polymer coating which totally covers the textile fabric.
The helix-type application of the polymer material upon the textile fabric creates a polymer coating which progresses uninterrupted in machine direction.
According to a fourth alternative and/or additional aspect of the invention, the present invention provides a method for the manufacture of a transport or process belt for a machine for the production or treatment of a fibrous web, in particular a paper, cardboard or tissue machine, by coating a permeable textile fabric with polymer material in a viscous state, whereby a gap shaped forming channel is formed through which the textile fabric is led, whereby the forming channel has a front and a back limiting area each extending parallel to the textile fabric and between which the textile fabric is guided, whereby a first forming belt is provided which provides one of the two limiting areas and which is moved in the same direction as the textile fabric and essentially at the same speed while the viscous polymer material is fed into the forming channel and is carried along by the textile fabric and the first forming belt. Thereafter the first forming belt is separated from the polymer material at the end of the forming channel, whereby the first forming belt in the area of one of its longitudinal edges—on the side facing the textile fabric—has an elevation extending parallel to the longitudinal edge of the forming belt which provides a laterally limiting area of the forming channel.
By providing a lateral limiting area of the forming channel through the forming belt, the width of the overlapping region of the adjacent coating segments can be defined. This allows for a defined control and improvement for bonding between the coated segments.
According to a fifth alternative and/or additional aspect of the invention, the present invention provides a method for the manufacture of a transport- or process belt for a machine for the production or treatment of a fibrous web, in particular a paper, cardboard or tissue machine, by coating a permeable textile fabric with polymer material in a viscous state, whereby a gap shaped forming channel is formed through which the textile fabric is led, whereby the forming channel has a front and a back limiting area each extending parallel to the textile fabric and between which the textile fabric is guided along a transport direction, whereby means are provided through which the textile fabric is held during coating with the viscous polymer material so that it causes no waves or wrinkles.
The means ensure that the textile fabric is centered in the polymer coating. It is further ensured that the textile fabric is evenly embedded in the polymer coating, thereby clearly increasing the dimensional stability of the finished transport or process belt.
BRIEF DESCRIPTION OF THE DRAWINGS
The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention will be better understood by reference to the following description of embodiments of the invention taken in conjunction with the accompanying drawings, wherein:
FIG. 1 shows a sectional view of an inventive transport or process belt along the machine direction of the belt;
FIG. 2 shows a repeat of the textile fabric of the belt illustrated in FIG. 1 ;
FIG. 3 shows a sectional view of the transport or process belt illustrated in FIG. 1 , along cross machine direction of the belt;
FIG. 4 shows a top view of a device to implement the inventive method for the manufacture of a belt as illustrated in FIG. 1 ;
FIG. 5 shows a side view of the device shown in FIG. 4 ;
FIGS. 6 a and 6 b shows the device from FIGS. 4 , 5 in the area of a forming belt at various steps in the manufacture of the belt illustrated in FIG. 1 ; and
FIG. 7 shows a top view of the device to implement the inventive method to manufacture a belt illustrated in FIG. 1 .
Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate embodiments of the invention, and such exemplifications are not to be construed as limiting the scope of the invention in any manner.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawings, and more particularly to FIG. 1 , there is shown one design form of an inventive transport or process belt 1 in a sectional plane extending in machine direction (MD). Belt 1 has a paper side 2 and a machine side 3 . Belt 1 further includes a polymer coating 4 and a textile load-bearing fabric structure 5 . Textile fabric 5 has a first side 6 facing paper side 3 and a second side 7 facing machine side 3 .
Textile fabric 5 is permeable and has a permeability of at least 300 cfm, preferably at least 550 cfm. Polymer coating 4 extends integrally from the first side 6 of textile fabric 5 through openings 8 in textile fabric 5 to the second side 7 of the textile fabric 5 .
Hereby the polymer coating 4 is preferably produced—at least from the first side 6 to the second side 7 of textile fabric 5 —from a single polymer material. This embodiment provides a belt which has practically no tendency to delaminate.
In the current example polymer coating 4 extends in a single piece from paper side 2 of belt 1 to machine side 3 of belt 1 , and is produced preferably from a single polymer material from paper side 2 of belt 1 to machine side 3 of belt 1 .
Belt 1 can have an overall thickness in the range of approx. 2 mm to approx. 6 mm, whereby preferably the ratio of overall thickness of belt 1 to the thickness of the textile fabric 5 is in the range of 2:1 to 5:1.
The total width of the belt can be in the range of approx. 1 m to approx. 12 m.
The polymer material of the polymer coating exemplarily includes polyurethane. Advantageously the polymer material consists completely of polyurethane. In addition one or several filler(s) may be embedded into polymer coating 4 .
Textile fabric 5 has a center plane extending through the center of the thickness of textile fabric 5 which is indicated in the illustration in FIG. 1 by line M-M. Preferably the same amount of polymer material is applied on both sides of the center plane so that polymer coating 4 has a uniform thickness with respect to the center plane.
In addition, polymer coating 4 is preferably impermeable, so that consequently an impermeable belt 1 is provided.
Textile fabric 5 preferably has a permeability in the range of approx. 500 cfm to approx. 1200 cfm, preferably approx. 550 cfm to approx. 900 cfm.
Textile fabric 5 can be formed by itself or in combination with a woven fabric, a spiral wire or a yarn array. In the current example the textile fabric is provided by a woven fabric.
Textile fabric 5 comprises machine direction threads 9 and cross machine direction threads 10 , whereby cross machine direction threads 10 have a greater flexural strength in their longitudinal direction than the machine direction threads 9 in their longitudinal direction. Textile fabric 5 which represents the load-bearing structure of the belt hereby gains a very high flexural strength in cross machine direction (CMD) and thereby a high dimensional stability. The higher flexural strength of cross machine direction threads 10 as opposed to the flexural strength of the machine direction threads can be achieved for example in that the machine direction threads 9 in their cross section have a greater width than height, whereas the cross machine threads 10 in their cross section have a width which is equal to the height. The different flexural strength may however also be influenced or completely determined by the selection of the material or materials from which machine direction threads 9 and cross machine direction threads 10 are manufactured.
In the current design example textile fabric 5 is in the embodiment of a woven fabric 5 , meaning that machine direction threads 9 are interwoven with cross machine direction threads 10 , whereby in order to form woven fabric 5 machine direction threads 9 are more curved in their longitudinal progression than the cross machine direction threads 10 in their longitudinal progression.
Cross machine direction threads 10 progress preferably not curved in their longitudinal direction.
According to a preferred embodiment of the invention, woven fabric 5 comprises a repeat weaving pattern. FIG. 2 illustrates such a repeat pattern. The repeat preferably includes machine direction threads of a first type 9 . 2 , 9 . 3 which, on the first side 6 of textile fabric 5 , cross a first number of successive cross machine threads 10 . 4 - 10 . 6 , 10 . 8 - 10 . 2 , 10 . 2 - 10 . 4 , 10 . 6 - 10 . 8 , creating a flotation F, before they continuously cross a single cross machine thread 10 . 3 , 10 . 7 , 10 . 1 , 10 . 5 on the second side 7 of woven fabric 5 while creating a bend K.
For example the machine direction thread of the first type 9 . 2 floats on the first side 6 of woven fabric 5 continuously over the three successive cross machine direction threads 10 . 4 - 10 . 6 before it runs on the second side 7 of the woven fabric and forms a bend K over the cross machine direction thread 10 . 7 .
In addition, the repeat includes preferably machine direction threads of the second type 9 . 1 , 9 . 4 which continuously form a flotation F on the second side 7 of woven fabric 5 in that they cross a second number of successive cross machine direction threads 10 . 4 - 10 . 6 , 10 . 8 - 10 . 2 , 10 . 2 - 10 . 4 , 10 . 6 - 10 . 8 before they run on the first side 6 of the woven fabric 5 and cross a single cross machine direction thread 10 . 3 , 10 . 7 , 10 . 1 by forming a bend K. Flotation F in the current example is to be understood to mean that a machine direction thread running on one side of the woven fabric crosses more than two successive cross machine direction threads without interweaving with a cross machine thread on the side opposite to the one side. Bend K in the current example is to be understood to mean that one machine direction thread on one side of the woven fabric continuously crosses only one single cross machine thread, whereby the machine direction thread on the side opposite the one side continuously crosses the cross machine threads which are located before and after this single cross machine thread.
As can be seen in the illustration in FIG. 2 it is advantageous if a bend K is located between successive flotations F, and a flotation F is located between successive bends K.
As illustrated in FIG. 2 , the first number of successive cross machine direction threads may also be the same as the second number of successive cross machine direction threads. In the current example the first and the second number is three. However, the first number and/or the second number could also be two, four or five.
In the repeat of woven fabric 5 the machine direction threads 9 . 1 - 9 . 4 are arranged preferably in the following sequence:
a first machine direction thread of the second type 9 . 1 which is followed by a first machine direction thread of the first type 9 . 2 which is followed by a second machine direction thread of the first type 9 . 3 , which again is followed by a second machine direction thread of the second type 9 . 4 .
Within the repeat of the woven fabric
the first machine direction thread of the second type 9 . 1 advantageously forms flotations F and bends K with the cross machine direction threads with which also the first machine direction thread of the first type 9 . 2 forms flotations F and bends K, also the first machine direction thread of the first type 9 . 2 and the second machine direction thread of the first type 9 . 3 forms bends K with different cross machine direction threads, also the second machine direction thread of the first type 9 . 3 forms flotations F and bends K with the cross machine direction threads with which also the second machine direction thread of the second type 9 . 4 forms flotations F and bends K.
The first machine direction thread of the first type 9 . 2 of the repeat and the second machine direction thread of the first type 9 . 3 may preferably be offset to each other by one to four, especially two cross machine direction threads 10 . 4 , 10 . 5 .
FIG. 3 shows a cross section of inventive belt 1 in cross machine direction (CMD). In the illustration of FIG. 3 belt 1 is seen in a section between two adjacent cross machine threads 10 . This means, in the illustration in FIG. 3 no cross machine direction thread 10 of the textile fabric in the embodiment of woven fabric 5 is seen. It can however be clearly seen that the polymer coating 4 extends integrally from the first side 6 of textile fabric 5 through openings 8 of textile fabric 5 to the second side 7 of textile fabric 5 .
Viewed in cross machine direction CMD polymer coating 4 consists of several coating segments 4 a - 4 d extending across a partial width of belt 1 , whereby adjacent coating segments 4 a - 4 d overlap in an overlap region 11 a - 11 c . Coating segments 4 a - 4 d are connected with each other at least in sections in overlapping region 11 a - 11 c , whereby bonding is provided preferably through chemical cross linking of the polymer material which provides coating segments 4 a - 4 d.
As can be seen from FIG. 3 the overlap regions 11 a - 11 c of adjacent coating segments 4 a - 4 d are formed in that one coating segment 4 a - 4 d forms a tab 12 a - 12 c protruding laterally in cross machine direction and having a lesser thickness than the remaining coating segment 4 a - 4 d which engages in a conforming recess 13 b - 13 d of the adjacent coating segment 4 a - 4 d.
As can be seen, tabs 12 a - 12 c essentially have a thickness which is consistent with the thickness of the textile fabric. This may be achieved for example by the special process control as described in FIGS. 6 a and 6 b . The length of tabs 12 a - 12 c in CMD can be influenced for example during the production process by the viscosity of the polymer material.
Viewed in cross machine direction at least some of the coating segments—for example in the illustration in FIG. 3 coating segments 4 b and 4 c include a tab 12 b , 12 c on the one end side and a recess 13 b , 13 c on the other end side respectively. (Note: as a rule all coating segments comprise always one tab and one recess with the exception of the coating segments which determine a longitudinal edge of the belt).
For example, coating segment 4 a viewed in cross machine direction forms tab 12 a on the one end side which, in order to form the overlap region 11 a engages in the conforming recess 13 b of the adjacent coating segment 4 b.
In addition each coating segment 4 a - 4 d has an upper and a lower outside surface whereby the upper and/or lower outside surfaces of adjacent coating segments smoothly adjoin.
FIGS. 4 and 5 show a machine by which an inventive transport or process belt can be produced. FIG. 4 shows the machine and a partially coated textile fabric 5 in a top view. A preferably permeable textile fabric 5 in the form of a continuous belt is stretched over an open distance S between two parallel rolls 16 , 17 . Textile fabric 5 has a first and a second longitudinal edge 14 , 15 extending respectively in the designated machine direction MD of belt 1 .
In order to coat textile fabric 5 with polymer material in a viscous state a coating apparatus 18 is used by means of which only a partial width of textile fabric 5 can simultaneously be coated. During the coating process continuous textile fabric 5 is moved in the designated machine direction MD of belt 1 and coating apparatus 18 for the viscous polymer material is moved in the designated cross machine direction CMD of belt 1 relative to each other so that after a single movement of coating apparatus 18 from first longitudinal edge 14 to second longitudinal edge 15 of textile fabric 5 the polymer material is applied in a helix-type path 19 onto textile fabric 5 , and textile fabric 5 is completely covered with polymer coating 4 .
Transport direction T of textile fabric 5 through forming channel 20 described in FIGS. 5-7 is consistent with the superimposed position of the movement of coating apparatus 18 with the movement of textile fabric 5 .
In addition the coating apparatus includes a holding device 43 by means of which textile fabric 5 is held in position during coating with the viscous polymer material 22 so that no waves or wrinkles occur.
During application of the helix-type path, the adjacent path segments form coating segments 4 a - 4 d which are known from FIG. 3 , whereby adjacent coating segments 4 a - 4 d overlap respectively in an overlap region 11 a - 11 c . The solid line in FIG. 4 represents the contact edge between adjacent coating segments 4 a - 4 d on the paper side of coating 4 . The respective overlap region 11 a - 11 c extends then always from the solid line to the broken line nearest to it.
It would also be conceivable not to apply the polymer coating in form of an uninterrupted helix type path of viscous polymer material onto the textile fabric, but instead apply several self-contained polymer paths which are located adjacent to each other in cross machine direction.
FIG. 5 shows a side view of the machine for the production of inventive belt 1 .
Coating apparatus 18 is shown. Coating apparatus 18 comprises a forming channel 20 through which textile fabric 5 which at this stage is uncoated at least across a partial width is fed from above and which leaves forming channel 20 in a downward direction, and coated across a partial width. Coating apparatus 18 further comprises means 21 to feed viscous polymer material 21 into forming channel 20 .
As already explained the permeable textile fabric has a first side 6 facing the provided paper side and a second side 7 facing the provided machine side.
Viscous polymer material 22 may be applied from one of the two sides 6 , 7 onto the permeable textile fabric 5 . In the current example viscous polymer material 22 is applied from the first side 6 of the fabric which faces the paper side 2 of belt 1 . It is however also conceivable to apply viscous polymer material 22 from the second side 7 of the textile fabric which faces the provided machine side 3 of belt 1 .
Due to the fact that polymer material 22 is applied from one of the two sides 6 , 7 in a viscous state onto permeable textile fabric 5 so that it flows from the first side 6 of textile fabric 5 through openings 8 of textile fabric 5 to the second side 7 of textile fabric 5 , an integral coating 4 is created which extends from the first side 6 to the second side 7 of textile fabric 5 and which, in contrast to a polymer coating which was applied from two sides onto the textile fabric, has practically no tendency to delaminate.
Influencing factors to cause viscous polymer material 22 to flow from first side 6 to second side 7 of the textile fabric may for example be the permeability and the time required to solidify the viscous polymer material. The time in which polymer material 22 is in the viscous state, and the permeability of textile fabric 5 can be coordinated so that the viscous polymer material can flow from first side 6 of textile fabric 5 through openings 8 of textile fabric 5 to its second side 7 .
Polymer material 22 may for example have a viscosity in the range of 250 cps to 1000 cps when reaching the forming channel which enables the viscous polymer material to flow from first side 6 of textile fabric 5 through openings 8 of textile fabric 5 to the second side 7 .
The polymer material is advantageously solidified after approx. 10 s to 150 s, especially after approx. 10 s to approx. 50 s from the viscous state to a green state.
In its viscous state polymer material 22 comprises a hardener component and a pre-polymer component. The time for solidification of the viscous polymer material and thereby the viscosity is herewith influenced by the initial weight ratio between hardener and pre-polymer, whereby the initial weight ratio is the weight ratio between hardener and pre-polymer at the time of intermixing. The initial weight ratio includes preferably more hardener than polymer. The polymer material includes especially a duroplastic. Advantageously the polymer is a duroplastic.
The initial weight ratio includes for example between 55% and 80% hardener and between 45% and 20% pre-polymer.
Tests conducted by the applicant have shown that the textile fabric advantageously has a permeability of at least 300 cfm, preferably of at least 550 cfm and a maximum of 1200 cfm.
FIGS. 6 a and 6 b illustrate coating apparatus 18 in the area of gap-shaped forming channel 20 along section A-A. Forming channel 20 progresses vertically. Air entrapments in the polymer material during coating can thereby be avoided.
Forming channel 20 is limited on one side and in its thickness by two forming belts 23 and 24 .
As already explained, during coating of the permeable textile fabric with viscous polymer material 22 , the textile fabric 5 is guided through gap-shaped forming channel 20 . Forming channel 20 has a front limiting area 25 and a rear limiting area 26 which respectively extend in forming channel 20 parallel to textile fabric 5 and between which textile fabric 5 is guided. First forming belt 23 provides the front limiting surface 25 and moves in the same direction as textile fabric 5 , and essentially at the same speed, while viscous polymer material 22 is fed into forming channel 20 and is carried along by textile fabric 5 and first forming belt 23 . At the end of forming channel 20 the first forming belt 23 is separated from the polymer material. As can be seen in FIG. 6 , first forming belt 23 has an elevation 28 (in the illustration in FIG. 6 in the area of its left longitudinal edge 27 ) on its side facing textile fabric 5 and progressing parallel to longitudinal edge 27 of forming belt 23 and which provides a lateral limiting area 29 of forming channel 20 .
Second forming belt 24 represents the other of the two limiting areas—in the current example the rear limiting area 26 —of forming channel 20 , whereby second forming belt 24 in the area of one of its longitudinal edges 30 on the side facing textile fabric 5 has an elevation 31 progressing parallel to longitudinal edge 30 of second forming belt 24 and providing a lateral limiting area 32 to forming channel 20 .
Second forming belt 24 also moves in the same direction as textile fabric 5 and essentially at the same speed while viscous polymer material 22 is fed into forming channel 20 and is carried along by textile fabric 5 and second forming belt 24 . At the end of forming channel 20 the second forming belt 24 is separated from the polymer material 22 .
As can be seen in the illustration in FIG. 6 a , elevation 28 of first forming belt 23 and elevation 31 of second forming belt 24 laterally limits forming channel 20 on the same side 34 . In addition, a segment 33 of textile fabric 5 is run between the two elevations 28 , 31 .
In the current example textile fabric 5 is run in the area of the forming channel squeezed between elevation 28 of first forming belt 23 and elevation 31 of second forming belt 24 . Viewed in width direction of forming channel 20 (this is consistent with cross machine direction CMD) elevations 28 , 31 of the two forming belts 23 , 24 are located at the same height for this purpose.
In other words, elevation 28 of first forming belt 23 and elevation 31 of second forming belt 24 , viewed in width direction (CMD) of forming channel 20 , are located relative to each other so that the lateral limiting area 29 of first forming belt 23 is arranged as an extension to lateral limiting area 32 of second forming belt 24 .
Since the two elevations 28 , 31 have the same height, textile fabric 5 is run centered between front limiting area 25 and rear limiting area 26 . If the two elevations were to have a different height, textile fabric 5 would be run off-center between front limiting area 25 and rear limiting area 26 .
In addition, forming channel 20 has no lateral limiting areas on the other side 35 , located opposite the one side 34 .
In addition, textile fabric 5 is wider than the two forming belts 23 , 24 viewed in width direction CMD of forming channel 20 .
By means of the design and layout of the two forming belts 23 , 24 described above, a coated area with a defined thickness is formed in the area between front limiting area 25 and rear limiting area 26 of forming channel 20 during coating of textile fabric 5 with viscous polymer material 22 ; and in the area between the two elevations 28 and 31 of the first 23 and the second forming belt 24 facing each other a tab 12 with a lesser thickness is formed onto the coated area.
On its side facing away from forming channel 20 , first forming belt 23 and/or second forming belt 24 may be supported on an opposite surface 36 , 37 in a way that the two forming belts 23 , 24 are run at a defined distance from each other in the area of forming channel 20 (see FIG. 5 ).
Each of forming belts 23 , 24 is continuous and is guided around two guide rolls 42 whereby the respective opposite surface 36 , 37 in the area of forming channel 20 is located between the two guide rolls 42 .
In addition, on the side facing away from forming channel 20 , first forming belt 23 and/or second forming belt 24 can have an elevation/recess 38 , 39 progressing parallel to longitudinal edge 27 , 30 of forming belt 23 , 24 with which forming belt 23 , 24 is guided along a corresponding recess/elevation 40 , 41 in the opposite surface 36 , 37 (see FIG. 6 a ).
The direction of travel of both forming belts 23 , 24 preferably encompasses an angle of 0.01° to 15°, in particular between 0.2° and 2°, with the longitudinal or machine direction MD of textile fabric 5 . Both forming belts 23 , 24 move in their direction of travel at a speed in the range of approx. 0.25 m/min. to 1.5 m/min.
FIG. 6 b illustrates the subsequent steps in the manufacture of transport or process belt 1 .
After the permeable textile fabric has been coated on a partial width with viscous polymer material 22 , thus forming the initial coated segment 4 a (as shown in FIG. 6 a ), permeable textile fabric 5 is coated with the viscous polymer material on an additional partial width which partially overlaps the one partial width, thus forming the subsequent coated segment 4 b which overlaps the initially formed coated segment 4 a in one overlap area 11 a in cross machine direction CMD.
For this purpose forming channel 20 and textile fabric 5 are moved relative to each other in their position in cross machine direction, so that forming channel 20 is located, in segments, in a partial area of the textile fabric which has not yet been provided with a coating segment. Since in the current example the polymer coating is applied in a helix-type path, shifting of the offset of the forming channel relative to the textile fabric occurs continuously. As can be seen from the illustration in FIG. 6 b , forming channel 20 is limited on the one side 34 by two lateral limiting areas 29 , 32 of both forming belts 23 , 24 , whereas on the other side 35 forming channel 20 is limited laterally by coating segment 4 a which was produced immediately prior. Here the two forming belts 23 , 24 overlap the initially formed coated segment 4 a so that, on the one hand, they rest on this coated segment 4 a and, on the other hand provide forming channel 20 .
As already explained, the initially formed coated segment 4 a has a tab 12 a in the overlap area 11 a , protruding in cross machine direction CMD and the additional subsequently formed coated segment 4 b has a corresponding recess 13 b with which tab 12 a engages.
Subsequently in the method a bond between the two coated segments 4 a and 4 b is caused in overlap area 11 a.
As already explained in the description of FIGS. 4 and 5 the two adjacent partially wide coated segments 4 a and 4 b are formed in that the continuous textile fabric 5 is coated with polymer material 22 in a partial width path 19 which runs around textile fabric 5 in a continuous helix type pattern.
Immediately after application of polymer material 22 , a conversion from the viscous state to a solid state of polymer material 22 is caused. Here it is conceivable that the bond of the two coated segments 4 a and 4 b in overlap area 11 a and the conversion of polymer material 22 from the viscous state to a solid state can occur at least partially simultaneously.
The conversion of polymer material 22 from the viscous state to the solid state includes preferably cross-linking of polymer material 22 . In other words, a chemical cross-linking takes place. For this purpose the polymer material may in particular have a hardener component and a pre-polymer component which are intermixed immediately prior to the coating process, whereby cross-linking begins immediately after mixing of the two components.
In order to achieve a good and solid bond of coating segments 4 a , 4 b in overlap area 11 a it is especially advantageous if coating of textile fabric 5 with the polymer material when creating the subsequent coating segment 4 b occurs, as long as the polymer material of the initially formed coated segment 4 a is not yet completely cross-linked. It is preferable if the subsequent coated segment is produced while the polymer material of the initially formed coated segment 4 a remains in a green state.
Tests conducted by the applicant have shown that the ratio between hardener and pre-polymer is adjusted so that the duroplastic polymer material 22 solidifies after approx. 10 s to 150 s, especially after approx. 10 s to approx. 50 s, from the viscous state to a green state.
Tests conducted by the applicant have further shown that a permanent bond of the coated segments which partially overlap each other can be achieved especially when an additional coated segment 4 b is formed within 24 hours after a prior coated segment 4 a was formed.
In order to make the bond between adjacent coated segments, for example 4 a and 4 b , or 4 b and 4 c , very durable it can be advantageous to subject the polymer material of the initially formed coated segment in the area of tab 12 b , 12 c , 12 d to a thermal treatment, especially a heat treatment immediately prior to creating the subsequent coated segment.
As can be seen from the illustrations in FIGS. 3 and 6 b the respective tab 12 a , 12 b , 12 c extends essentially inside textile fabric 5 which, in the current example, can be achieved by the specific embodiment of the two forming belts 23 , 24 and their positioning relative to each other.
Tabs 12 a - 12 c essentially have a thickness which is consistent with the thickness of textile fabric 5 . This can be achieved for example by the specific process control, in other words in that textile fabric 5 is run between the two elevations 28 , 31 of the two forming belts 23 , 24 . The length of tabs 12 a - 12 c can be influenced, for example, through the viscosity of the polymer material during the manufacturing process.
Application of the polymer material is preferably conducted so that the tab of the coated segment which is produced first extends in cross machine direction between 10 mm and 50 mm, especially between 20 mm and 35 mm, into the recess of the subsequently formed coated segment.
The application of the polymer material is in addition conducted preferably so that the respective coated segments 4 a - 4 d extend in cross machine direction CMD between 100 mm and 500 mm, especially between 150 mm and 300 mm.
As can be seen from the illustration in FIG. 6 b , polymer coating 4 which is formed by the different coated segments preferably provides machine side 2 and/or paper side 3 of belt 1 .
In addition all coated segments 4 a - 4 d have preferably the same thickness, whereby the upper and/or the lower outside surfaces of adjacent coating segments 4 a - 4 d smoothly adjoin.
It can also be seen in the illustration in FIG. 6 b that polymer coating segments 4 a - 4 d extend at least in some regions from the first side 6 of textile fabric 5 through openings 8 of textile fabric 5 to the second side 7 of textile fabric 5 . Each of the coating segments 4 a - 4 d is integral.
FIG. 7 shows a simplified illustration of the device depicted in FIGS. 4-6 in the area of the two forming belts. It can be said generally that in the method for the manufacture of the transport or process belt by means of coating permeable textile fabric 5 with polymer material 22 in a viscous state, textile fabric 5 is run through the gap-shaped forming channel 20 , whereby forming channel 20 has a front limiting area 25 and a rear limiting area 26 which respectively extend parallel to textile fabric 5 and between which textile fabric 5 is guided along a transport direction (Note: in FIG. 7 the transport direction extends essentially vertically to the drawn plane; the transport direction results from superimposing of the movement of textile structure 5 in machine direction and cross-directional movement of coating apparatus 18 ).
In addition, means are provided by which textile fabric 5 is held in position during coating with the viscous polymer material so that it does not produce any waves or wrinkles. In the current example the means include a first and a second holding device 43 , 47 arranged at the height of forming channel 20 and having opposite surfaces 48 - 51 between which textile fabric 5 is squeezed.
The two holding devices 43 , 47 are located outside forming channel 20 .
Holding textile fabric 5 in position hereby includes stretching of textile fabric 5 in forming channel 20 , in cross direction to the transport direction.
As already explained, front limiting area 25 of forming channel 20 is provided by first forming belt 23 ; and rear limiting area 26 of forming channel 20 is provided by second forming belt 24 between which textile fabric 5 is guided. Here, the two forming belts 23 , 24 run in the same direction and essentially at the same speed as the textile fabric 5 .
First holding device 43 —viewed in cross direction to the transport direction—is located at a distance from the two forming belts 23 , 24 , whereby the distance between first holding device 43 and the two forming belts 23 , 24 is between 10 cm and 100 cm, preferably between 30 cm and 55 cm.
In the first holding device 43 the two opposite surfaces 48 , 49 are provided by a pair of rollers 44 , 45 which are rotatable in transport direction of the textile fabric.
Second holding device 47 is provided by the two elevations 28 , 31 of forming belts 23 , 24 which face toward textile fabric 5 and between which textile fabric 5 is squeezed and guided. In the second holding device 47 an offset of the two opposite surfaces 50 , 51 at cross direction to the transport direction is preferably avoided through appropriate means, thereby further avoiding creation of waves or folds in the textile fabric.
Textile fabric 5 is held by the two holding devices 43 , 47 in an area which has not yet been coated, whereby textile fabric 5 is coated in the second holding device 47 during the holding process and while a tab is formed.
Textile fabric 5 is held in position during the coating process by the two holding devices 43 , 47 so that a centered position of textile fabric 5 in the polymer coating 4 is ensured. In addition, occurrence of wrinkles or waves in textile fabric 5 is avoided during the coating process. Obviously, according to the invention only one of the two holding devices 43 , 47 may be provided. However, provision of both holding devices 43 , 47 provides an especially effective centering of textile fabric 5 , as well as effective avoidance of wrinkles and waves.
In the current example the two opposite surfaces are provided by a pair of rolls 44 , 45 which are rotatable in transport direction of textile fabric 5 , whereby in the current example each of the two opposite surfaces is rigidly connected with one of the two forming belts 23 , 24 .
While this invention has been described with respect to at least one embodiment, the present invention can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims. | The invention relates to a transport or processing belt for a machine for the production or treatment of a fiber web, particularly a paper, cardboard or tissue machine, having a paper side and a conveying side and comprising a polymer coating and a textile load-bearing fabric, wherein the textile fabric has a first side facing the paper side and a second side facing the conveying side. The textile fabric is permeable with a permeability of at least 300 cfm, preferably of at least 500 cfm, and the polymer coating extends in one piece from the first side of the textile fabric though the openings of the textile fabric to the second side of the textile fabric. | 3 |
TECHNICAL FIELD OF THE INVENTION
The present invention relates in general to optical systems for projecting an image of a mask on a substrate in laser material processing applications. The invention relates in particular to methods and apparatus for uniformly illuminating the mask.
DISCUSSION OF BACKGROUND ART
In laser material processing applications, such as crystallization, annealing, or nozzle drilling systems, a certain spatial distribution of laser radiation on a substrate or material being processed is often required. One well-known method of providing the spatial distribution includes illuminating an area of a mask which has a pattern of apertures therein with the laser radiation, and projecting an image of the aperture patterns on the substrate. Certain applications, particularly laser crystallization, demand a very high degree of uniformity of illumination of the mask.
Several arrangements have been used or proposed for providing such uniform illumination on a mask. The complexity of the arrangements is usually inversely dependent on the quality of the laser radiation delivered from the laser providing that radiation. More complex designs are required for lasers that provide beams that are multimode in at least one axis, are not symmetrical in cross-section, or have an intensity distribution that is not Gaussian in at least one axis. The effectiveness of any such arrangement, of course, can be compromised if the distribution of radiation in the beam varies with time. This can occur in gas-discharge lasers, particularly in high-pressure, pulsed gas-discharge lasers such as excimer lasers. Such variations can be random variations on a spatial scale that is a fraction of the overall dimensions of the laser-beam, and can appear as spatial modulations in a more general distribution of the radiation on the substrate. The variations can also be longer term, temporal variations that effect primarily the general distribution of the radiation on the substrate. Optical arrangements for re-distribution of radiation in a laser-beam have relied on using devices such as anamorphic optical systems, diffractive optical elements, and “beam homogenizing” devices such as microlens arrays, diffusers, and light-pipes.
In prior-art excimer-laser projection systems it has been possible to provide a general or intensity variation as low as between about 1% about 2% of nominal over the illuminated area using a combination of anamorphic optical elements and anamorphic microlens arrays to shape and homogenize radiation in the laser-beam. Radiation distribution at this level of uniformity often rises from a low level at edges of the illuminated area to a maximum at the center of the illuminated area. This is sometimes referred to by practitioners of the art as a “center-up” distribution. In certain demanding applications, laser crystallization in particular, an absolute intensity variation of less than 1.5% is preferred. When random and temporal variations of energy distribution are combined with the 1% and 2% general energy distribution variation of 1.5% or less is difficult to achieve consistently. Accordingly, there is a need to reduce the variation in general distribution of energy below the level that has been achieved to date in prior-art laser projection systems.
SUMMARY OF THE INVENTION
The present invention is directed to a method and apparatus for illuminating a mask with a beam of radiation from a laser. In one aspect, the present invention comprises directing the laser beam through a plurality of optical elements located on a longitudinal axis. The optical elements are arranged to project the beam onto the mask to illuminate the mask. The configuration and arrangement of the optical elements is selected such that the intensity of radiation in the laser-radiation beam on the mask is nearly uniform in a transverse axis of the beam. Uniformity of radiation in the laser-radiation beam on the mask in the transverse axis is optimized by partially blocking at least one edge of the laser-radiation beam at a location between selected ones of the optical elements.
In another aspect of the invention, the edge blocking of the laser-radiation beam is accomplished by a least one stop extending partially into the laser-radiation beam at the selected location. In one preferred embodiment of the invention, the stop has a width less than the transverse-axis width of the laser-radiation beam and the stop has a rounded tip at an end thereof extending into the laser-radiation beam. In one example, the nearly uniform distribution provided by the optical elements is the above discussed “center-up” distribution having a single, central, peak value and a 2σ (two standard deviations) uniformity of about 2.08%. In one uniformity-optimization provided by the edge-blocking with the stop, the optimized distribution has two peak values having a centrally located trough value therebetween, and has a 2σ uniformity of about 1.36%.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are incorporated in and constitute a part of the specification, schematically illustrate a preferred embodiment of the present invention, and together with the general description given above and the detailed description of the preferred embodiment given below, serve to explain principles of the present invention.
FIG. 1 is a three-dimensional view schematically illustrating an excimer laser projection system in accordance with the present invention including an excimer laser delivering a laser-beam having a long-axis and a short-axis perpendicular to each other, an anamorphic telescope arranged to expand and shape the laser-beam, a beam homogenizer including two pairs of cylindrical-microlens arrays for spatially redistributing energy in the expanded, shaped laser-beam, a narrow stop arranged to partially block the expanded, shaped and partially homogenized beam between two of the microlens arrays, and condensing and field lenses for focusing the shaped, homogenized beam onto a mask.
FIG. 2 schematically illustrates one preferred example of the beam-stop of FIG. 1 having a rounded tip for insertion into the beam.
FIG. 3 is an elevation view of the projection system of FIG. 1 seen in the short-axis of the laser-beam, and schematically illustrating a preferred positioning of the beam-stop between arrays in one pair of the microlens arrays of FIG. 1 and illustrating further detail of the condensing optics and mask.
FIG. 4A is an elevation view seen in the short-axis of the laser-beam, and schematically illustrating details of the beam-stop and the beam between the microlens arrays of FIG. 3 .
FIG. 4B is a plan view from above seen in the long-axis of the laser-beam, and schematically illustrating further details of the beam stop and the beam between the microlens arrays of FIG. 4A .
FIG. 5 is a graph schematically illustrating intensity as a function of distance along the long-axis of the beam on the mask in one example of the projection system of FIG. 1 from which the beam stop has been removed from the beam.
FIG. 6 is a graph schematically illustrating intensity as a function of distance along the long axis of the beam on the mask in another example of the projection system of FIG. 1 in which the beam stop is of the form depicted in FIG. 2 , and aligned with the propagation axis of the beam and partially inserted into the beam by an experimentally determined distance along the short-axis direction of the beam.
FIG. 7 is a graph schematically illustrating intensity as a function of distance along the long axis of the beam on the mask in yet another example of the projection system of FIG. 1 in which the beam stop is of the form depicted in FIG. 2 , and aligned with the propagation axis of the beam and partially inserted into the beam along the short axis direction of the beam beyond the distance of the example of FIG. 6 .
FIGS. 8A-D are three-dimensional views schematically illustrating alternate arrangements of two or more beam stops between the microlens arrays of FIG. 3 .
FIG. 9 is a three-dimensional view schematically illustrating an arrangement of a beam stop in accordance with the present invention between microlens arrays of another pair of microlenses of FIG. 1 .
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawings, wherein like components are designated by like reference numerals, FIG. 1 , FIGS. 2A and 2B , FIG. 3 , and FIGS. 4A and 4B schematically illustrate an embodiment 10 of an optical system in accordance with the present invention for projecting an image of a mask on a substrate. An excimer laser (not shown) delivers a beam 14 propagating along a system axis (the Z-axis in an X, Y, Z, Cartesian axis system). In an optical system such as system 10 it is usual to provide a variable attenuator (also not shown) to allow power in the beam to be varied according to the application. A description of such an attenuator is not necessary for understanding principles of the present invention.
Beam 14 , on leaving the excimer laser, has an elongated cross-section. In one example of an excimer laser the beam leaving the laser has a width of about 12.0 mm and a length of about 35.0 mm. The length and width of the beam define the X and Y-axes, which are often referred to by practitioners of the excimer laser art as the long-axis and short-axis respectively.
Turning mirrors 42 and 44 direct the beam (after having traversed any attenuator) into an anamorphic telescope 18 , here, including cylindrical lenses 46 and 48 and a spherical lens 50 . The purpose of telescope 18 is to adapt the beam to the aperture of a beam-homogenizer formed by microlens arrays 54 , 56 , 58 and 60 . Details of the telescope and other important system groups are depicted in FIGS. 1 and 3 . FIG. 1 is a three dimensional view. FIG. 3 is a view in the plane of the short-axis of optical system 10 showing further detail of components of system 10 . In FIG. 3 , the long-axis appearance of certain components is schematically depicted in dashed lines and designated by reference numerals having a subscript L. In FIGS. 1 and 3 , only the general direction of propagation of beam 14 is depicted, as a single line collinear with the longitudinal optical axis (the Z-axis) of system 10 . In FIGS. 4A and 4B , multiple lines 14 depict bounds of the beam.
A turning mirror 52 directs the collimated beam into the beam homogenizing arrangement 20 comprising microlens arrays 54 , 56 , 58 , and 60 . Microlens array 54 includes a plurality of elongated plano-convex cylindrical microlenses 55 and microlens array 56 includes a plurality of elongated plano-convex microlenses 57 . Microlens arrays 54 and 56 can be described as the “long-axis beam-homogenizer”. Preferably there are twelve microlenses in each array, however, in FIG. 3 only four microlenses are depicted in each array for convenience of illustration. The microlenses in each array are aligned parallel to the short-axis and have positive optical power in the long-axis and zero optical power in the short-axis. The microlenses in one array are arranged as a long-axis optical relay with corresponding microlenses in the other array. Beam 14 next traverses microlens arrays 58 and 60 , forming what can be described as the “short-axis beam-homogenizer”. Microlens array 58 includes a plurality of plano-convex cylindrical microlenses 59 and microlens array 60 includes a plurality of planoconvex microlenses 61 . Again, only four microlenses are depicted in each array for convenience of illustration. The microlenses in each array are aligned parallel to the long-axis and have positive optical power in the short-axis and zero optical power in the long-axis. The microlenses in one array are arranged as a short-axis optical relay with corresponding microlenses in the other array.
Located between microlenses 58 and 60 is an elongated partial-shutter or beam-stop 62 , details of a preferred form of which are schematically depicted in FIG. 2 . Interaction of the stop with the beam, and a preferred location of the stop with respect to the beam are schematically depicted in FIGS. 4A and 4B . The purpose of stop 62 is to prevent the above discussed “center-up” intensity distribution in an image projected on the substrate by the optical system. Stop 62 preferably has a width W (see FIG. 2 ) that is between about 5% and about 50% of the long-axis width BW of beam 14 between microlenses 58 and 60 (see FIG. 4B ). The stop preferably has a rounded tip 62 A having a radius about equal to W/2. The stop is preferably positioned over the longitudinal axis 15 of the optical system (see again FIG. 4B ). The stop is preferably positioned closer to microlens array 60 (the exit microlens array of the short-axis beam-homogenizer) than to microlens 58 (the entrance microlens array of the short-axis beam-homogenizer), and most preferably positioned immediately adjacent the exit microlens array. It is also possible that stop 62 be located adjacent microlens array 60 , between lens 22 and microlens array 60 . Stop 62 preferably extends into the beam in the short-axis direction for a distance between about 3% and about 35% of the short axis beam height (see FIG. 4A ). The stop must not, however, extend across the system optical axis. The optimum extension-distance may vary from system to system but can be quickly determined experimentally for any stop dimension in the preferred range.
After traversing the short-axis beam-homogenizer, the collimated beam 14 traverses a spherical lens 22 having positive power and is directed by turning mirrors 66 , 68 , and 70 to a plano-convex cylindrical lens 24 having positive power in the short-axis and zero-optical power in the long-axis. After traversing lens 24 the beam traverses another plano-convex cylindrical lens 26 . Lens 26 has positive power in the long-axis and zero-optical power in the short-axis. An effect of lenses 22 , 24 , and 26 is project beam 14 on a mask 28 with an elongated cross-section (indicated in FIG. 1 by dashed line 30 ) having a length between about 25 mm and 125.0 mm and a width 8 between about 3 mm and 25 mm. That portion 14 S (see FIG. 3 ) of beam 14 passing through patterns of apertures (not shown) is directed by turning mirrors 72 and 74 to an imaging lens 32 . Imaging lens 32 focuses light 14 S as an image (not shown) of the aperture patterns in mask 28 . The long-axis distribution of light intensity on mask 28 produced by the above described optical elements (normally center-up) can be modified according to the shape and positioning of stop 62 . This modification is discussed below, beginning with reference to FIG. 5 .
FIG. 5 is a graph schematically illustrating intensity as a function of distance along the long-axis of the beam on mask 28 in one example of the optical system 10 of FIG. 1 from which stop 62 has been removed from the beam. Intensity distribution is measured between points designated by dashed lines L 5 and R 5 . It can be seen that between those lines the intensity rises steadily from each line never falling below the lowest value in the measurement range (indicated by horizontal line H 5 ) and reaching a peak value about mid-way between lines L 5 and R 5 . This is the above-described center-up distribution that stop 62 is able to modify. In this measurement, the intensity variation between the lines L 5 and R 5 is 2σ=2.08% (where σ is the standard deviation from the mean).
FIG. 6 is a graph schematically illustrating intensity as a function of distance along the long-axis of the beam on mask 28 in one example of the optical system 10 of FIG. 1 including a stop 62 in accordance with the present invention. In this example, the long-axis beam width (BW) between microlens arrays 58 and 60 is about 100 mm. Stop 62 has a width W of about 15 mm with a rounded tip 62 A having a radius of about 7.5 mm. Microlens arrays 58 and 60 are axially spaced apart by about 330 mm, and stop 62 is located about 15 mm from microlens array 60 . Short-axis beam width BH at the location of stop 62 is about 25 mm. It is believed that stop 62 extends between about 3 mm and 6 mm into the beam in the short-axis direction into the beam.
It should be noted, in this regard, that the exact extension of the beam was not measured, and in fact, as the edge of the beam can not be precisely defined, an exact extension is equally difficult to define. An optimum extension of the stop was determined by testing various extension depths of the stop and measuring the long-axis intensity distribution of radiation at the mask level.
Intensity distribution is measured between points designated by dashed lines L 6 and R 6 . It can be seen that between those lines the intensity initially rises steadily from each line to a peak value close to each of the lines falling to a lower value, centrally, between the two peaks. The intensity, however, never falls below the lowest (edge) value in the range, indicated by horizontal line H 6 . In this measurement the intensity variation between the lines L 6 and R 6 is about 1.36% (2σ).
FIG. 7 is a graph schematically illustrating intensity as a function of distance along the long-axis of the beam on mask 28 in another example of the optical system 10 of FIG. 1 including a stop 62 in accordance with the present invention. In this example, the dimensions of stop 62 , the spacing of the microlens arrays, the beam widths between the microlens arrays and the axial distance position of stop 62 from microlens array 60 are the same as in the example of FIG. 6 . In this example, however, stop 62 extends deeper into the beam in the short-axis direction into the beam than in the example of FIG. 6 .
Intensity distribution is measured between points designated by dashed lines L 7 and R 7 . It can be seen that between those lines the intensity initially rises steadily from each line to a peak value close to each of the lines falling to a value below the lowest (edge) value in the range, indicated by horizontal line H 7 . Further, there is significant, relatively high frequency, modulation over about one-half of the long-axis extent of the beam. This modulation has a peak-to-valley excursion comparable to the total intensity variation in the example of FIG. 6 . In the graph of FIG. 7 , the intensity variation between the lines L 7 and R 7 is about 7.14% (2σ).
In other experiments, the effect of placing a stop at other locations was investigated, for example, closer to microlens array 58 than to microlens array 60 , and at various positions between microlens arrays 54 and 56 . In each case, the effect was to produce modulation comparable to or greater than the modulation exhibited in the example of FIG. 7 .
It is believed that a stop having a rounded tip, whether semicircular as in the examples described, or having some non-semicircular curvature such as elliptical, parabolic, or hyperbolic, will provide an intensity distribution having less modulation than would be produced by a tip having an angular form, however, the use of a stop having a tip of an angular form is not precluded. It is also possible that a variation of intensity less than 1.3% may be obtained by arranging two or more stops 62 in the edge of the beam. Some possible arrangements of the stops between microlens arrays 58 and 60 are schematically depicted in FIGS. 8A , 8 B, 8 C, and 8 D.
In the arrangement of FIG. 8A there are two stops, one thereof in an upper edge of the beam and the other in the lower edge of the beam. The stops, here, are aligned with each other, and aligned over system axis 15 . In the arrangement of FIG. 8B there are also two stops, but each thereof is in the upper edge of the beam, and the stops are aligned with one on either side of the system axis in the long axis direction. In the arrangement of FIG. 8C there are two stops in the upper edge of the beam aligned as in the arrangement of FIG. 8B and one stop in the lower edge of the beam aligned over the system axis as in FIG. 8A . In the arrangement of FIG. 8D , there is one stop in the upper edge of the beam and one stop in the lower edge of the beam. Here, the stops are aligned displaced from the system axis on opposite sides thereof.
It may also be possible to improve short-axis beam uniformity by inserting one or more stops into the beam between microlens arrays 54 and 56 of the long-axis beam homogenizer. An arrangement in which one stop is inserted is depicted in FIG. 9 . Here, the stop extends partially into the beam in the long-axis direction. Those skilled in the art will recognize without further illustration or detailed description that multiple stop arrangements are also possible for improving short-axis beam uniformity.
It is emphasized, here, that the multiple stop arrangements described above are merely a sample of possible such arrangements that may provide improved beam uniformity. Whatever the number and alignment of the stops, however, each stop should have a width less than the long-axis beam width at the location of the stops, and should not extend into the beam across the system axis. It is also emphasized that while the present invention is described above in the context of a particular excimer-laser projection system in which the efficacy of the invention has been experimentally determined, the invention is applicable in other laser projection systems having a different arrangement of beam shaping, projection optics, or beam homogenizing optics.
The present invention is described above in terms of a preferred and other embodiments. The invention is not limited, however, to the embodiments described and depicted. Rather, the invention is limited only by the claims appended hereto. | An optical system for projecting a laser-beam on a mask to illuminate the mask includes a beam homogenizing arrangement including spaced arrays of microlenses. The beam homogenizing arrangement redistributes light in the laser beam such that the intensity of light in the laser-beam on the mask is nearly uniform along a transverse axis of the laser-beam. A stop extending partially into the laser-beam between the microlens arrays provides a more uniform light-intensity on the mask along the transverse axis than can be achieved by the microlens arrays alone. | 6 |
The present invention relates to proteins for novel ATP-sensitive potassium channels, hUK ATP -1 and ruK ATP -1, that are expressed in various tissues of human and rat origins, and to genes encoding the same. The said proteins and genes can be used as diagnostic and therapeutic agents for potassium-channel related diseases such as diabetes, hypertension and endocrine insufficiencies.
BACKGROUND OF THE INVENTION
The etiology for diabetes is known to be mostly owing to disturbances of insulin secretion in the pancreatic β-cells. Consequently, elucidation of the molecular mechanism of insulin secretion is expected to play an important role in the clarification of causes for diabetes and the development of therapeutic agents against diabetes, but no detail has yet been made known on such molecular mechanism.
It has already been made clear that the ATP-sensitive potassium channel (K ATP ) being present on the cellular membrane plays a leading role in the cellular functions such as secretions and muscular contraction by coupling the state of metabolism in the cells with the membrane potential.
The K ATP channel was first discovered in the cardiac muscle in 1983 Noma, A., Nature 305:147 (1983)! and was thereafter confirmed to be present in tissues such as the pancreatic β-cell Cook, D. L. et al., Nature 311:271 (1984), Misler, S. et al., Proc. Natl. Acad. Sci. U.S.A. 83:7119 (1986)!, pituitary Bernardi, H. et al., Proc. Natl. Acad. Sci. U.S.A., 90:1340 (1993)!. skeletal muscle Spruce, A. E., et al., Nature, 316:736 (1985)! and brain.
In addition, it has been suggested that there exists the molecular heterogeneity of such K ATP channels Ashcroft, F. M., Annu. Rev. Neurosci. 11:97 (1988)!.
Particularly in the pancreatic β-cells, ATP produced by the metabolism of glucose brings about calcium ion inflow from the calcium channel by closing the K ATP channel to cause depolarization, resulting in secretion of insulin. As is evident from this, the K ATP channel plays a leading role in regulating the secretion of insulin.
The K ATP channel belongs to a potassium channel family exhibiting electrophysiologically inward rectification, whereby the potassium channel family exhibiting inward rectification is classified into the four subfamilies, ROMK1, IRK1, GIRK1 and cK ATP -1, on the basis of the degree of amino acid sequence identity.
Nevertheless, there has not been clarified the molecular architecture for the K ATP channel in the pancreatic β-cells. In addition, no information has been disclosed on the novel ATP-sensitive potassium channels (huK ATP -1 and ruK ATP -1) of the present invention for the detailed protein structure and the formation of complexes with other proteins, for example, the sulfonylurea binding protein.
SUMMARY OF THE INVENTION
In order to achieve the isolation, identification and functional analyses of a novel membrane channel, there are required the sophisticated techniques, such as molecular biological technique, cellular biological technique and electro-physiological technique.
Such being the case, the present inventors made ample and full use of such techniques to isolate human and rat genomes and cDNAs encoding the novel K ATP channel (uK ATP -1) expressed in different tissues of mammalians and to identify their amino acid sequences (see FIGS. 1, 2, 3 and 4). The identified uK ATP -1 channel was expressed in the Xenopus oocyte system and mammalian cell lines.
Electrophysiological analysis demonstrated that uK ATP -1 is an ATP-sensitive potassium channel exhibiting inward rectification. The uK ATP -1 channel being expressed ubiquitously in tissues of mammalians inclusive of man and rats is involved in the maintenance of the membrane potential through the basal energy metabolism.
As is described in the above, the present invention relates to an ATP-sensitive potassium channel (uK ATP -1) which is ubiquitously present in mammalians, and encompasses the ATP-sensitive potassium channel proteins, identified DNA sequences encoding the same, plasmid having such sequences incorporated therein and furthermore recombinant cells (tranformants) having such plasmid transfected therein. In addition, this invention comprises the isolated uK ATP -1 proteins and recombinant proteins, their related materials such as agonists and antagonists, and drug designs inclusive of diagnostics and drugs for gene therapy.
DETAILED DESCRIPTION
huK ATP -1 of a human origin is composed of 324 amino acid residue (See FIG. 1 (SEQ. ID NO: 1)) with a molecular weight of 47,965, while the one of a rat origin is likewise composed of 424 amino acid residue (see FIG. 4 (SEQ. ID NO: 4)) with a molecular weight of 47,960. These two potassium channels exhibit 98% amino acid sequence identity, and such a marked homology leads us to the assumption that uK ATP -1 performs common, structurally and functionally basic actions in all mammalian cells. Among others, uK ATP -1 participates in the membrane potential and energy metabolism, suggesting that it could find application as a drug substance acting to prevent disturbances under unusual, extreme metabolic conditions inclusive of endocrine diseases, e.g. diabetes, starvation and ischemia.
For example, the inflow and outflow of calcium ions caused by the opening and closing of uK ATP -1 during the onset of ischemia is closely connected with ischemic disturbances. In other words, there is a possibility that the agonists and antagonists for the opening and closing of uK ATP -1 would constitute a suppressory agent against ischemic disturbances.
From the comparative studies of huK ATP -1 and ruK ATP -1 with other potassium channels for the amino acid sequence, it was confirmed that uK ATP -1 of the present invention belongs to a novel family of the inward rectifier potassium channels; the central region of the uK ATP -1 protein showed increased homology with other inward rectifier potassium channels. A hydropathy plot indicated the presence of two hydrophobic regions, which are composed of two transmembrane regions characteristic of the inward rectifier potassium channels and one pore region Nicholas, C. G., Trends Pharmacol. Sci., 14:320 (1993), Jan, L. Y. and Jan, Y. N., Nature, 371:119 (1994)!.
With reference to ruK ATP -1 (Inagaki, N. et al., J. B. C., 270:5691 (1995)!, it was reported that in the second intracellular region, there are two potential cAMP-dependent protein kinase phosphorylation sites (Thr-234 and Ser-385) and seven potential protein kinase C dependent phosphorylation sites (Ser-224, Thr-345, Ser-354, Ser-379, Ser-385, Ser-391 and Ser-397), while there are one (Thr-63) and four potential casein kinase II dependent phosphorylation sites (Thr-234, Ser-281, Thr-329 and Ser-354) in the first and second intracellular regions, respectively, with no N-linked glycosylation site being present in the intracellular regions. The same findings were obtained with huK ATP -1 Inagaki, N., et al., in press (1995)!.
Then, the present inventors identified the nucleotide sequences and entire amino acid sequences of huK ATP -1 and ruK ATP -1, thus enabling not only proteins themselves of huK ATP -1 and ruK ATP -1 but also their mutants to be synthesized in large quantities by expressing the DNAs encoding huK ATP -1 and ruK ATP -1 and their mutants in bacteria or animal cells with use of the known genetic engineering techniques. It is furthermore added that huK ATP -1 and its fragments are useful for the hybridization diagnosis of depleted huK ATP -1 DNA, with the mutants of huK ATP -1 being of use in the studies on the sugar metabolism in cells, particularly insulin-dependent and independent diabetes.
The DNAs of novel huK ATP -1 and ruK ATP -1 according to the present invention were identified based on a cDNA library and genome library. The DNA encoding huK ATP -1 shows a length of about 9.7 kb, being composed of three exons and is present on the chromosome at 12p11.23. The chromosomal DNA can be obtained by probing a genome DNA library with use of cDNAs for uK ATP -1 and its fragment, as well. The isolated uK ATP -1 DNA can easily be subjected to nucleotide depletion, insertion or replacement by the known techniques to prepare its mutants.
By employing the known techniques, it is easy to link nucleotide sequences encoding other proteins or synthetic polypeptides to uK ATP -1 or its variants at the 5' and 3' ends to thereby prepare fusion proteins, or derivatives thereof.
For example, a fusion protein is prepared as a precursor protein and undergoes cleavage in vivo or in vitro to thereby perform functions; such fusion protein provides target-tissue and membrane orientation in addition to its proper function. In such a case, the fusion proteins contain sugar-chain binding amino acids, and can be modified to derivatives having tissue orientation or physiological activities activated by adding new sugar chains.
In order to produce uK ATP -1, its mutants or their derivatives, the corresponding coding DNA is incorporated into a reproducible plasmid, and host cells being transformed with such plasmid are incubated. The host cells include bacteria, yeasts and animal cells.
Prokaryotes such as bacteria are suited for the cloning of deoxyribonucleotides. For example, pBR 322 plasmid derived from E. coli contains a gene resistant to ampicillin or tetracycline and can provide a practical means of identifying the transformed cells. Furthermore, the microbial plasmids contain a promoter which can be used to express their proteins themselves. In addition to prokaryotes, eukaryotes such as yeasts can work well, with a plasmid YRp7 being utilizable especially in allowing the expression in yeasts of the species Saccharomyces Stinchomb et al., Nature, 282:39 (1979)!.
Animal cells are also used as a host, and particularly the incubation of vertebra cells is employable easily and constitutes a conventional means Krause and Paterson, Tissue Culture, Academic Press (1973)!. As the cell lines, there are mentioned AtT-20, Hela cells, Chinese hamster ovary (CHO), COMSM6, COS-7 and the like. The promoters of Polyomavirus. Adenovirus 2, Cytomegalovirus and Simian virus 40 are used to control the function of expression plasmid in such cell lines, wherein pCMV is a plasmid which finds widened application in the expression systems of animal cells Thomsen et al., PNAS, 81:659 (1984)!.
The DNA sequences for the channel protein and huK ATP -1 and muK ATP -1 according to the present invention begin with the initiation codon "ATG". In cases where the recombinant cells are used to synthesize such protein, there is no need to add ATG to the desired DNA, thus making the manipulation easy. When uK ATP -1 is expressed in a prokaryote transformed with E. coli, consequently, there is generally synthesized a protein of the amino acid sequence beginning with Met. The N-terminated met of the resultant protein may be eliminated according to the purpose of application.
In cases in which uK ATP -1 is synthesized in recombinant animal cells, similarly, proteins having Met contained or eliminated at the N-terminal are bio-synthesized, and both are useful for individually intended application purposes.
uK ATP -1 and its fragments can be administered to animals for their immunization to thereby produce antibodies. Also, immunization of animals permits a monoclonal antibody to be produced from cells secreting the desired antibody.
It has become easy to prepare uK ATP -1 in large quantities, thus providing better understanding of the same at the molecular level. Accordingly, the production of uK ATP -1 and its mutants or analogs raises the possibility to develop diagnostics or therapeutics for the channel-protein related diseases.
In particular, such proteins can be utilized in the procedures of investigating into a substance suited for diagnostics and therapeutics, or a substance that exerts agonistic or antagonistic action on uK ATP -1. For example, a testing procedure with animal cells can be conducted by injecting cDNA for uK ATP -1 into cells to conduct expression, followed by addition of sulfonylurea to study their interactions Kayano, T. et al., J. Biol. Chem., 265:13276 (1990), Example 4!.
Additionally, the pertinent information has been obtained on the DNA sequence of uK ATP -1, facilitating DNA or RNA encoding their fractional sequences to be prepared. Such relatively short DNA sequences possess the capability to hybridize with the gene to be selected, and can find application as a probe, which probe is effective for detection of cDNAs in different tissues.
The probe as prepared with use of uK ATP -1 can be utilized to produce nucleic acids capable of hybridization from a variety of organisms and their tissues. The resultant nucleic acids may be the same type as uK ATP -1 or its isoform and include nucleic acids encoding the novel proteins.
The prepared probe is utilizable in the gene diagnosis of potassium-channel related diseases; investigation can be conducted into patients' nucleotide sequences hybridized with the probe capable of detecting the disease genes.
The blocker and opener agents for the potassium channel have heretofore been used as therapeutics against diabetes and hypertension. uK ATP -1 and its mutants, their derivatives and monoclonal antibodies to them, when processed into pharmaceutical preparations, can be administered to patients to thereby alleviate through neutralization the adverse effects brought about by an excess of such blocker or opener agents administered clinically. When uK ATP -1 itself shows functional insufficiency, such pharmaceutical preparations can be administered to thereby make up for such deficient functions of uK ATP -1.
The present invention comprises the preparation of drugs for gene therapy being applicable in the essential treatment method. The nucleotide sequences for uK ATP -1 or its mutants and their derivatives can be incorporated into plasmid or stem cells, which are then given patients to open up the possibility of finding application as a drug for gene therapy.
Below described are the examples to illustrate the present invention in more detail, while referring to the appended drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 (SEQ. ID NO: 1) is an illustration of the amino acid sequences corresponding to the base sequences as shown in FIG. 2 (SEQ. ID NO: 2).
FIG. 2 (SEQ. ID NO: 2) is an illustration of the base sequence of uK ATP -1 of a human origin as obtained in Example 5.
FIG. 3 (SEQ. ID NO: 3) is an illustration of the amino acid sequence corresponding to FIG. 4.
FIG. 4 (SEQ. ID NO: 4) is an illustration of the base sequence of ruK ATP -1 of a
FIG. 5A shows the results of electrophysiological analysis of ruK ATP -1 with use of Xenopus oocytes. The oocytes injected with cRNA of ruK ATP -1 exhibited inward rectification under conditions of 45 mM K + ! concentrated extracellular fluid, which rectification was however blocked with 300 μM of Ba 2+ added to the extracellular fluid. The control, which comprised injection of water, was observed to produce negligible slight inward electric current alone.
FIG. 5B is a plot of potassium-concentration dependent electric current versus voltage, leading to the confirmation that the uK ATP -1 evidently is an inward rectifier potassium channel.
FIG. 5C is a plot of reversible voltage versus a logarithm of extracellular K + concentration in the oocyte injected with cRNA for ruK ATP -1, indicating the dependency of the reversible voltage on the extracellular K + concentration.
FIG. 6 is a single-channel analysis of HEK 239 transformed cells having uK ATP -1 expressed therein, wherein A represents recordings of single-channel current and B is a current-voltage relationship, demonstrating the presence of a K + current showing inward rectification.
EXAMPLE 1
cDNA cloning of a novel inward rectifier potassium channel (ruK ATP -1)
A cDNA fragment of GIRK, rat G protein regulating, inward rectifier potassium channel, was amplified by the polymerase chain reaction (PCR) method. Using a 32 P-labeled rat GIRK cDNA fragment as a probe, search was made into a cDNA library made from rat islets of Langerhans in the vector of λgt22. The isolated ruK ATP -1 cDNA was cut into suitable DNA fragments, and after subcloning into M13mp18 or mp19, base sequencing was performed by the chain terminator method (see FIGS. 5 and 6).
EXAMPLE 2
Expression in Xenopus laevis oocytes and electrophysiological analysis
A 20 ng quantity of cRNA synthesized in vitro from plasmid pGEM11Z containing a full-length ruK ATP -1 cDNA with the RNA polymerase after being linearized through treatment with a restriction enzyme Not1 was injected into Xenopus oocytes, followed by electrophysiological analysis 2 or 3 days later. (see FIG. 7). As is illustrated in FIGS. 7A and 7B, there was observed a K + electric current showing weak inward rectification. The K + electric current was suppressed by adding Ba 2+ in the exracellular fluid.
EXAMPLE 3
Single-channel analysis of HEK 239 cells having ruK ATP -1 expressed
HEK 239 cells were cultured in minimum essential Eagle's medium supplemented with 10% of horse serum. The expression plasmid (pCMV6b) carrying a full-length ruK ATP -1 coding cDNA was transfected into HEK 239 cells with use of Lipofectamine to prepare transformed HEK 293 cells. The transformed cells produced in this manner were subjected to single channel analysis, with the results being shown in FIGS. 6A and 6B.
As is evident in FIGS. 8A and 8B, the outward electric current flowing through the channel was suppressed by the intracellular Mg 2+ , revealing that uK ATP -1 is an inward rectifier K + channel; uK ATP -1 exhibited a single-channel conductance of ca. 70 pS. FIG. 5 illustrates effects of ATP on the uK ATP -1 channel activity as observed in the inside-out mode. When 1 μM of ATP was added inside the cellular membrane, the channel was open but closed completely upon addition 1 mA of ATP. The results indicate that uK ATP -1 is an ATP-regulated K ATP channel.
EXAMPLE 4
RNA Blotting analysis
A 20 μg portion of RNA extracted individually from various tissues and cell lines as well as 10 μg of RNA extracted from the pituitary and thyroid glands were denatured with formaldehyde and electrophoresed on 1% agarose gel, followed by transferring onto a Nylon membrane. Using 32 P labeled ruK ATP -1 cDNA as a probe, hybridization was carried out, with the expression of uK ATP -1 mRNA being observed in almost all tissues.
EXAMPLE 5
Cloning of cDNA and gene of uK ATP -1 of a human origin
In order to isolate cDNA encoding uK ATP -1 of a human origin, search was effected into a human lung cDNA library using 32 P labeled ruK ATP -1 cDNA of a rat origin as a probe. The resultant clone was subjected to sub-cloning into M13mp18, M13mp19 and pGEM3Z, followed by base sequencing by the chain terminator method.
__________________________________________________________________________# SEQUENCE LISTING- (1) GENERAL INFORMATION:# 4 (iii) NUMBER OF SEQUENCES:- (2) INFORMATION FOR SEQ ID NO: 1:- (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 424 ami - #no acids (B) TYPE: amino aci - #d (C) STRANDEDNESS: sing - #le# linear (D) TOPOLOGY:- (xi) SEQUENCE DESCRIPTION: SEQ ID NO: - # 1:- Met Leu Ala Arg Lys Ser Ile Ile Pro Glu Gl - #u Tyr Val Leu Ala Arg# 15- Ile Ala Ala Glu Asn Leu Arg Lys Pro Arg Il - #e Arg Asp Arg Leu Pro# 30- Lys Ala Arg Phe Ile Ala Lys Ser Gly Ala Cy - #s Asn Leu Ala His Lys# 45- Asn Ile Arg Glu Gln Gly Arg Phe Leu Gln As - #p Ile Phe Thr Thr Leu# 60- Val Asp Leu Lys Trp Arg His Thr Leu Val Il - #e Phe Thr Met Ser Phe#80- Leu Cys Ser Trp Leu Leu Phe Ala Ile Met Tr - #p Trp Leu Val Ala Phe# 95- Ala His Gly Asp Ile Tyr Ala Tyr Met Glu Ly - #s Ser Gly Met Glu Lys# 110- Ser Gly Leu Glu Ser Thr Val Cys Val Thr As - #n Val Arg Ser Phe Thr# 125- Ser Ala Phe Leu Phe Ser Ile Gln Val Gln Va - #l Thr Ile Gly Phe Gly# 140- Gly Arg Met Met Thr Glu Glu Cys Pro Leu Al - #a Ile Thr Val Leu Ile145 1 - #50 1 - #55 1 -#60- Leu Gln Asn Ile Val Gly Leu Ile Ile Asn Al - #a Val Met Leu Gly Cys# 175- Ile Phe Met Lys Thr Ala Gln Ala His Arg Ar - #g Ala Glu Thr Leu Ile# 190- Phe Ser Arg His Ala Val Ile Ala Val Arg As - #n Gly Lys Leu Cys Phe# 205- Met Phe Arg Val Gly Asp Leu Arg Lys Ser Me - #t Ile Ile Ser Ala Ser# 220- Val Arg Ile Gln Val Val Lys Lys Thr Thr Th - #r Pro Glu Gly Glu Val225 2 - #30 2 - #35 2 -#40- Val Pro Ile His Gln Leu Asp Ile Pro Val As - #p Asn Pro Ile Glu Ser# 255- Asn Asn Ile Phe Leu Val Ala Pro Leu Ile Il - #e Cys His Val Ile Asp# 270- Lys Arg Ser Pro Leu Tyr Asp Ile Ser Ala Th - #r Asp Leu Ala Asn Gln# 285- Asp Leu Glu Val Ile Val Ile Leu Glu Gly Va - #l Val Glu Thr Thr Gly# 300- Ile Thr Thr Gln Ala Arg Thr Ser Tyr Ile Al - #a Glu Glu Ile Gln Trp305 3 - #10 3 - #15 3 -#20- Gly His Arg Phe Val Ser Ile Val Thr Glu Gl - #u Glu Gly Val Tyr Ser# 335- Val Asp Tyr Ser Lys Phe Gly Asn Thr Val Ly - #s Val Ala Ala Pro Arg# 350- Cys Ser Ala Arg Glu Leu Asp Glu Lys Pro Se - #r Ile Leu Ile Gln Thr# 365- Leu Gln Lys Ser Glu Leu Ser His Gln Asn Se - #r Leu Arg Lys Arg Asn# 380- Ser Met Arg Arg Asn Asn Ser Met Arg Arg As - #n Asn Ser Ile Arg Arg385 3 - #90 3 - #95 4 -#00- Asn Asn Ser Ser Leu Met Val Pro Lys Val Gl - #n Phe Met Thr Pro Glu# 415- Gly Asn Gln Asn Thr Ser Glu Ser 420- (2) INFORMATION FOR SEQ ID NO: 2:- (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 1275 ba - #se pairs (B) TYPE: nucleic acid (C) STRANDEDNESS: single#linear (D) TOPOLOGY:- (xi) SEQUENCE DESCRIPTION: SEQ ID NO: - # 2:- ATGTTGGCCA GAAAGAGTAT CATCCCGGAG GAGTATGTGC TGGCGCGCAT CG - #CCGCAGAG 60- AACCTGCGCA AGCCGCGCAT CCGAGACCGC CTCCCCAAAG CCCGCTTCAT CG - #CCAAGAGC 120- GGGGCCTGCA ACCTGGCGCA TAAGAACATC CGTGAGCAAG GACGCTTTCT AC - #AGGACATC 180- TTCACCACCT TGGTGGACCT GAAATGGCGC CACACGCTGG TCATCTTTAC CA - #TGTCCTTC 240- CTCTGCAGCT GGCTGCTCTT CGCTATCATG TGGTGGCTGG TGGCCTTTGC CC - #ATGGGGAC 300- ATCTATGCTT ACATGGAGAA AAGTGGAATG GAGAAAAGTG GTTTGGAGTC CA - #CTGTGTGT 360- GTGACTAATG TCAGGTCTTT CACTTCTGCT TTTCTCTTCT CCATTGAAGT TC - #AAGTTACC 420- ATTGGGTTTG GAGGGAGGAT GATGACAGAG GAATGCCCTT TGGCCATCAC GG - #TTTTGATT 480- CTCCAGAATA TTGTGGGTTT GATCATCAAT GCAGTCATGT TAGGCTGCAT TT - #TCATGAAA 540- ACAGCTCAGG CTCACAGAAG GGCAGAAACT TTGATTTTCA GCCGCCATGC TG - #TGATTGCC 600- GTCCGAAATG GCAAGCTGTG CTTCATGTTC CGAGTGGGTG ACCTGAGGAA AA - #GCATGATC 660- ATTAGTGCCT CTGTGCGCAT CCAGGTGGTC AAGAAAACAA CTACACCTGA AG - #GGGAGGTG 720- GTTCCTATTC ACCAACTGGA CATTCCTGTT GATAACCCAA TCGAGAGCAA TA - #ACATTTTT 780- CTGGTGGCCC CTTTGATCAT CTGCCACGTG ATTGACAAGC GCAGTCCCCT GT - #ATGACATC 840- TCAGCAACTG ACCTGGCCAA CCAAGACTTG GAGGTCATAG TTATTCTGGA AG - #GAGTGGTT 900- GAAACTACTG GCATCACCAC ACAAGCACGA ACCTCCTACA TTGCTGAGGA CA - #TCCAATGG 960- GGCCACCGCT TTGTGTCCAT TGTGACTGAG GAAGAAGGAG TGTATTCTGT GG - #ATTACTCC1020- AAATTTGGCA ACACTGTTAA AGTAGCTGCT CCACGGTGCA GTGCCCGAGA GC - #TGGATGAG1080- AAACCTTCCA TCCTTATTCA GACCCTCCAA AAGAGTGAAC TGTCTCATCA AA - #ATTCTCTG1140- AGGAAGCGCA ACTCCATGAG AAGAAACAAT TCCATGAGGA GGAACAATTC TA - #TCCGAAGG1200- AACAATTCTT CCCTCATGGT ACCAAAGGTG CAATTTATGA CTCCAGAAGG AA - #ATCAAAAC1260# 1275- (2) INFORMATION FOR SEQ ID NO: 3:- (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 424 ami - #no acids (B) TYPE: amino acid (C) STRANDEDNESS: sing - #le#linear (D) TOPOLOGY:- (xi) SEQUENCE DESCRIPTION: SEQ ID NO: - # 3:- Met Leu Ala Arg Lys Ser Ile Ile Pro Glu Gl - #u Tyr Val Leu Ala Arg# 15- Ile Ala Ala Glu Asn Leu Arg Lys Pro Arg Il - #e Arg Asp Arg Leu Pro# 30- Lys Ala Arg Phe Ile Ala Lys Ser Gly Ala Cy - #s Asn Leu Ala His Lys# 45- Asn Ile Arg Glu Gln Gly Arg Phe Leu Gln As - #p Ile Phe Thr Thr Leu# 60- Val Asp Leu Lys Trp Arg His Thr Leu Val Il - #e Phe Thr Met Ser Phe#80- Leu Cys Ser Trp Leu Leu Phe Ala Ile Met Tr - #p Trp Leu Val Ala Phe# 95- Ala His Gly Asp Ile Tyr Ala Tyr Met Glu Ly - #s Gly Ile Thr Glu Lys# 110- Ser Gly Leu Glu Ser Ala Val Cys Val Thr As - #n Val Arg Ser Phe Thr# 125- Ser Ala Phe Leu Phe Ser Ile Glu Val Gln Va - #l Thr Ile Gly Phe Gly# 140- Gly Arg Met Met Thr Glu Glu Cys Pro Leu Al - #a Ile Thr Val Leu Ile145 1 - #50 1 - #55 1 -#60- Leu Gln Asn Ile Val Gly Leu Ile Ile Asn Al - #a Val Met Leu Gly Cys# 175- Ile Phe Met Lys Thr Ala Gln Ala His Arg Ar - #g Ala Glu Thr Leu Ile# 190- Phe Ser Arg His Ala Val Ile Ala Val Arg As - #n Gly Lys Leu Cys Phe# 205- Met Phe Arg Val Gly Asp Leu Arg Lys Ser Me - #t Ile Ile Ser Ala Ser# 220- Val Arg Ile Gln Val Val Lys Lys Thr Thr Th - #r Pro Glu Gly Glu Val225 2 - #30 2 - #35 2 -#40- Val Pro Ile His Gln Gln Asp Ile Pro Val As - #p Asn Pro Ile Glu Ser# 255- Asn Asn Ile Phe Leu Val Ala Pro Leu Ile Il - #e Cys His Val Ile Asp# 270- Lys Arg Ser Pro Leu Tyr Asp Ile Ser Ala Th - #r Asp Leu Val Asn Gln# 285- Asp Leu Glu Val Ile Val Ile Leu Glu Gly Va - #l Val Glu Thr Thr Gly# 300- Ile Thr Thr Gln Ala Arg Thr Ser Tyr Ile Al - #a Glu Glu Ile Gln Trp305 3 - #10 3 - #15 3 -#20- Gly His Arg Phe Val Ser Ile Val Thr Glu Gl - #u Glu Gly Val Tyr Ser# 335- Val Asp Tyr Ser Lys Phe Gly Asn Thr Val Ar - #g Val Ala Ala Pro Arg# 350- Cys Ser Ala Arg Glu Leu Asp Glu Lys Pro Se - #r Ile Leu Ile Gln Thr# 365- Leu Gln Lys Ser Glu Leu Ser His Gln Asn Se - #r Leu Arg Lys Arg Asn# 380- Ser Met Arg Arg Asn Asn Ser Met Arg Arg Se - #r Asn Ser Ile Arg Arg385 3 - #90 3 - #95 4 -#00- Asn Asn Ser Ser Leu Met Val Pro Lys Val Gl - #n Phe Met Thr Pro Glu# 415- Gly Asn Gln Cys Pro Ser Glu Ser 420- (2) INFORMATION FOR SEQ ID NO: 4:- (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 1275 ba - #se pairs (B) TYPE: nucleic acid (C) STRANDEDNESS: single#linear (D) TOPOLOGY:- (xi) SEQUENCE DESCRIPTION: SEQ ID NO: - # 4:- ATGCTGGCCA GGAAGAGCAT CATCCCGGAG GAGTATGTGC TGGCCCGCAT CG - #CGGCGGAG 60- AACCTGCGCA AACCGCGCAT CCGCGACCGC CTCCCCAAAG CCCGCTTCAT CG - #CCAAGAGC 120- GGAGCCTGCA ACCTGGCTCA CAAGAACATC CGAGAGCAAG GTCGCTTCCT GC - #AGGACATC 180- TTCACCACCT TGGTAGACCT GAAGTGGCGT CACACGCTGG TCATCTTCAC CA - #TGTCCTTC 240- CTCTGCAGCT GGCTGCTCTT CGCTATCATG TGGTGGCTGG TGGCCTTCGC CC - #ACGGGGAC 300- ATCTATGCTT ACATGGAGAA AGGCATCACG GAGAAGAGTG GCCTGGAGTC TG - #CCGTCTGT 360- GTGACCAATG TCAGGTCATT CACTTCTGCG TTTCTCTTCT CCATCGAGGT TC - #AAGTGACC 420- ATTGGGTTTG GAGGGAGAAT GATGACTGAG GAGTGCCCTC TGGCCATCAC GG - #TTTTGATT 480- CTGCAGAACA TTGTGGGTCT GATCATCAAC GCGGTCATGT TGGGCTGCAT CT - #TCATGAAG 540- ACGGCCCAGG CCCACAGAAG GGCAGAGACG CTGATTTTCA GCCGCCATGC TG - #TAATTGCG 600- GTCCGTAATG GCAAGCTGTG CTTCATGTTC CGGGTGGGTG ACCTGAGGAA AA - #GCATGATC 660- ATTAGCGCCT CGGTGCGCAT CCAGGTGGTC AAGAAAACCA CGACGCCAGA AG - #GAGAGGTG 720- GTGCCTATTC ACCAGCAGGA CATCCCTGTG GATAATCCCA TCGAGAGCAA TA - #ACATCTTC 780- CTAGTGGCCC CTTTGATCAT CTGCCATGTG ATTGATAAGC GTAGCCCCCT GT - #ACGATATC 840- TCAGCCACTG ACCTTGTCAA CCAAGACCTG GAGGTCATAG TGATTCTCGA GG - #GCGTGGTG 900- GAAACCACGG GCATCACCAC GCAAGCGCGG ACCTCCTACA TTGCAGAGGA GA - #TCCAGTGG 960- GGACACCGCT TCGTGTCGAT TGTGACTGAG GAGGAGGGAG TGTACTCTGT GG - #ACTATTCT1020- AAATTTGGTA ATACTGTGAG ACTGGCGGCG CCAAGATGCA GTGCCCGGGA GC - #TGGACGAG1080- AAACCTTCCA TCTTGATTCA GACCCTCCAA AAGAGTGAAC TGTCGCACCA GA - #ATTCTCTG1140- AGGAAGCGCA ACTCTATGAG AAGAAACAAC TCCATGAGGA GGAGCAACTC CA - #TCCGGAGG1200- AATAACTCTT CCCTCATGGT GCCCAAGGTG CAATTCATGA CTCCAGAAGG AA - #ACCAGTGC1260# 1275__________________________________________________________________________ | The present invention provides novel ATP-sensitive potassium-channel proteins which are present ubiquitously in the living bodies of animals, and their genes. | 0 |
RELATED APPLICATIONS
[0001] This application claims priority from U.S. Provisional Application No. 60/627,894, the contents of which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to brackets and, more particularly, to a universal support bracket for mounting equipment on industrial pipes.
[0004] 2. Description of the Prior Art
[0005] Over the years various brackets have been developed for securing pipes, such as those used in the plumbing industry, to surrounding structural members of a building. On the other hand, according to the applicant's knowledge, very few brackets exist for mounting equipment directly on insulated or non-insulated industrial pipes, such as the pipes used in the gas/oil and water treatment industries. Presently, what is being used in the industry to mount components on industrial pipes are costly custom built support systems welded to structural steel, which is subject to corrosion from chemicals used in the oil, gas, petrochemical and water treatment industries. Such brackets cannot be mounted directly on the protective sheet covering industrial insulated pipes.
[0006] There is thus a need for a new bracket that can be readily installed on a wide variety of industrial pipes in order to support pieces of equipment thereon.
SUMMARY OF THE INVENTION
[0007] It is therefore an aim of the present invention to provide a new bracket for supporting components on industrial pipes.
[0008] It is also an aim of the present invention to provide a new bracket that can be mounted to industrial piping without damage to the pipe insulation liner and without heat transfer to the items mounted on the bracket.
[0009] Therefore, in accordance with the present invention, there is provided a bracket for mounting equipment on a member, comprising a saddle adapted to be positioned against an outer surface of the member, a connector for releasably securing said saddle in position on the member, and an upstanding rail projecting from said saddle and along which a fastening device carrying a piece of equipment to be mounted on the member is slidably received and releasably securable at various axial position therealong.
[0010] In accordance with a further embodiment of the present invention, there is provided a bracket adapted to be releasably mounted on industrial pipes of various diameters to support various pieces of equipment at a certain distance away from the pipes, the bracket comprising a base having an arcuate bottom pipe engaging surface adapted to be positioned against an outer surface of a pipe, an attachment member for releasably securing the base in place on the pipe, said attachment member being adjustable to accommodate pipes of different diameters, and a rail extending from the base in a direction away from said arcuate bottom surface thereof, said rail being adapted to adjustably receive therealong a fastening device carrying an accessory to be mounted on the pipe.
[0011] In accordance with a still further general aspect of the present invention, there is provided a bracket adapted to be releasably mounted on industrial pipes of various diameters to support various pieces of equipment at a certain distance away from the pipes, the bracket comprising a rail having first and second opposed axial ends, said rail defining an axially extending channel between the first and second ends thereof, said channel being adapted to slidably receive a fastening device carrying a piece of equipment to be mounted on a pipe, a base provided at said first axial end of said rail, said base having an arcuate bottom surface adapted to be positioned against an outer surface of the pipe, and a clamp for releasably securing said base in place on the pipe.
[0012] In accordance with a further general aspect of the present invention, there is provided a bracket adapted to be mounted to a surface for supporting various pieces of equipment at a certain distance away from the surface, the bracket comprising a base having a bottom surface adapted to be placed against the surface to which a piece of equipment has to be mounted, fastening means for securing said base in position on the surface, and a rail extending from the base in a direction away from said bottom surface thereof, said rail being adapted to adjustably receive therealong a fastening device carrying the piece of equipment to be mounted on the surface.
[0013] In accordance with a further general aspect of the present invention, there is provided a bracket and pipe arrangement comprising a pipe, a bracket and a piece of equipment to be mounted to the pipe, the bracket supporting the piece of equipment at a certain distance away from the pipe, the bracket comprising a base having a bottom surface embracing an outer surface of the pipe, fastening means for securing said base in position on the outer surface of the pipe, and a rail extending from the base in a direction away from said bottom surface thereof, said piece of equipment being adjustably mounted along said rail and securable at various axial positions therealong.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Having thus generally described the nature of the invention, reference will now be made to the accompanying drawings, showing by way of illustration a preferred embodiment thereof, and in which:
[0015] FIG. 1 is a perspective view of a bracket for mounting various accessories on industrial pipes of different diameters in accordance with a preferred embodiment of the present invention;
[0016] FIG. 2 is a schematic side view of an industrial pipe on which a pair of axially spaced-apart support brackets are mounted for supporting a cable tray at a desired distance away from the pipe in accordance with one potential application of the present invention;
[0017] FIG. 3 is a schematic end view of the cable tray with electrical wires supported by the brackets shown in FIG. 1 , and
[0018] FIG. 4 is a schematic side view of an industrial pipe on which a number of support brackets are mounted for supporting a plurality of electrical cables connected to a temperature or pressure measurement transmitter mounted on the pipe in accordance to a further potential application of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0019] FIG. 1 shows a universal mounting bracket 10 adapted to be mounted to industrial pipes of various diameters to support thereon a variety of components, such as electrical wiring, electrical junction boxes, piping, cable or instrument tray, instrument air lines, glycol heat trace lines and other pieces of equipment commonly used in the oil/gas and water treatment industries.
[0020] The bracket 10 generally comprises a saddle 12 in the form of a rectangular base plate having a smooth arcuate bottom surface 13 adapted to be placed directly against a pipe. It is understood that the base plate could be of any other shape. The bracket 10 is specifically well suited to be mounted on insulated industrial piping, 4 inches to 24 inches in diameter with an added 2 inches of heat resistant insulation and a protective aluminum sheeting cover. The smooth saddle shape of the base plate allows the bracket 10 to be mounted directly on the insulation protective cover, because it contours the pipe, thus evenly distributing the weight over the entire surface area of the contact zone. Therefore, the bracket 10 can be mounted without damage to insulation and without heat transfer to the items mounted on the bracket 10 , the insulation protective cover of the pipe acting as a thermal barrier to prevent heat transfer to the equipment supported by the bracket 10 . This constitutes a major advantage over known support brackets that cannot be mounted to the exterior of the insulation of the piping as it would damage the outer protective liner over the insulation. Although the bracket 10 is specifically designed to permit mounting on insulated pipes, it is understood that the bracket 10 could also be directly installed on a non-insulated industrial pipe.
[0021] A pair of removable flexible bands 14 is provided at opposed ends of the saddle 12 for releasably securing the saddle 12 in position on the pipe. Each band 14 is preferably provided in the form of ½ inch aluminum or stainless steel banding. The bands 14 can be adjusted to virtually fit any pipe size. Other types of clamping bands adapted to encircle the pipe could also be used to clamp the saddle 12 in position against the outer surface of the pipe. For instance, hose clamps or straps with transversal ratchet teeth could also be used to affix the saddle 12 to the pipe. Slotted holes could be defined in the saddle 12 for receiving the clamping bands or straps. Other adjustable attachment means or connectors are contemplated as well.
[0022] The bracket 10 further includes a universal extruded aluminum rail 16 of the type often used in the electrical industry and which is configured to accept more than 100 different fastening devices presently used in this industry. It is understood that the rail 16 could be made of any other corrosion resistant material, such as plastic and composite materials. The extruded aluminum rail 16 is welded in an upright position to the top of the saddle 12 . According to the illustrated embodiment, the rail 16 projects at right angles from the top surface of the saddle 12 . Alternatively, it could be welded at other angles to the saddle 12 . The rail has a proximal end 20 welded to the saddle 12 and a free distal end 22 . The rail 16 defines an axially extending channel 24 having a bottom surface 26 from opposed sides of which projects a pair of side walls 28 . Each side wall 28 is bent inwardly at 90° to define a top wall surface 30 extending in parallel to the bottom surface 26 . Each top wall surface 30 is provided at an inner end thereof with an in turn lip 32 extending towards the bottom surface 26 and parallel to the sidewalls 28 . The lips 32 define therebetween an axially extending slot for allowing a rail engaging member to be captively inserted into the channel 24 . In the illustrated embodiment, the channel 24 opens on a side of the saddle 12 . However, it is understood that the rail 16 could be welded to the saddle 12 with the open side of the channel 24 facing one end of the saddle 12 or at angles less than or greater than 90° as needed.
[0023] The bracket 10 , including the saddle 12 , the rail 16 and the banding 14 , is preferably manufactured out of aluminum rather than plastic or even stainless steel because the pure aluminum composition thereof enables it to withstand harsh environmental treatment from exposure to the most corrosive atmospheres, which is required by the industries. The reason it is possible to use a heat conducting material such as aluminum in contact with industrial piping and steam lines heated up to 350 degrees Celsius, is due to the outer insulation protective cover of the pipes. Heat transfer to items mounted on the bracket 10 does not occur because the insulation acts as a heat barrier, blocking the heat from traveling from one medium to the other. Although aluminum is the preferred material, other material could be used depending on the environment in which it is used. For instance, the bracket 10 could be made out of a material which is U.V. rated as it would be in direct sun light in 60% of its intended use.
[0024] FIG. 2 is a side view of an industrial pipe 36 on which a pair of brackets 10 are attached with ½″ aluminum or stainless steel banding 14 . Standard fastening devices are slidably engaged in the rails 16 of the brackets 10 to support a cable tray 38 of the type commonly used in the industry to house a bundle of electrical wires 43 (see FIG. 3 ). The position of the fastening devices along the rails 16 can be adjusted as desired in order to mount the tray 38 at a given distance from the outer surface of the pipe 36 .
[0025] FIG. 4 illustrates another potential application of the present invention and wherein a pair of brackets 10 is releasably secured in position on a pipe 40 to support electrical cables 41 connected to a temperature or pressure measurement transmitter 42 directly mounted on the pipe 40 .
[0026] The present invention could also be used to mount equipment on various flat surfaces (building studs, flat steel, etc.). In this case, the base plate or saddle 12 would be flat. Holes (not shown) could be defined in each corner of the plate for receiving a fastener, such as a screw or a nail.
[0027] The embodiments of the invention described above are intended to be exemplary. Those skilled in the art will therefore appreciate that the forgoing description is illustrative only, and that various alternatives and modifications can be devised without departing from the spirit of the present invention. Accordingly, the present is intended to embrace all such alternatives, modifications and variances which fall within the scope of the appended claims. | A bracket adapted to be releasably mounted on industrial pipes of various diameters to support various pieces of equipment at a certain distance away from the pipes. The bracket comprises a base having an arcuate bottom pipe engaging surface adapted to be positioned against an outer surface of a pipe. Banding is provided for releasably securing the base in place on the pipe. An upstanding rail extends at right angles from the base for adjustably receiving therealong a fastening device carrying an accessory to be mounted on the pipe. | 7 |
BACKGROUND OF THE INVENTION
Field of the Invention
The present invention relates to a sealed top cover and lid for washing machine.
One way to improve the accessibility to the interior of top loading washing machines is to provide an access opening which has a downwardly inclined wall adjacent the top front edge of the washing machine. However some means must be provided for preventing splashed fluid or condensation from draining downwardly and forwardly on the inclined wall to the exterior of the washing machine. Also it is desirable to confine sound within the washing machine to make it quieter in the room in which it is operating.
Many devices have been used for dispensing fluids such as liquid detergents into washing machines. Some of these devices have been provided inside the washing machine and some have been provided on the lid for the washing machine. These prior art devices however have been deficient in many respects.
Many of these devices have been small in volume. They also failed to provide a satisfactory means for metering the amount of fluid dispensed, and for permitting the user to determine the amount of fluid left in the dispenser.
Therefore, a primary object of the present invention is the provision of an improved sealed top cover and lid for a washing machine.
A further object of the present invention is the provision of an improved washer lid having a fluid dispenser which will hold a large quantity of fluid for use in many washing loads.
A further object of the present invention is the provision of an improved washer lid having a fluid dispenser which is comprised of two chambers, one of which is a reservoir chamber and the other of which is a dispensing chamber.
A further object of the present invention is the provision of an improved washer lid which includes a counter balance for counter balancing the weight of the fluid in the fluid dispenser.
A further object of the present invention is the provision of an improved washer lid and method for using same which permits the metering of the amount of fluid to be dispensed.
A further object of the present invention is the provision of an improved washer lid having a dispenser which contains a viewing window therein for observing the quantity of fluid within the dispensing chamber.
A further object of the present invention is the provision of an improved washer lid having a fluid dispenser with a window and a movable marker for marking the level of fluid desired to be dispensed.
A further object of the present invention is the provision of an improved washer lid which includes a fluid dispenser and a seal for sealing splashed fluid or condensation inside the washer when the lid is closed.
A further object of the present invention is the provision of an improved washer lid having a fluid dispenser with a valve for dispensing fluid from the fluid dispenser.
A further object of the present invention is the provision of an improved washer lid having a fluid dispenser with a removable valve which can be easily removed and cleaned.
A further object of the present invention is the provision of an improved lid having a fluid dispenser which is registered above the washer access opening when the lid is in its open position so that fluid can be dispensed directly into the access opening by gravity.
A further object of the present invention is the provision of an improved lid which recharges the dispensing chamber each time the lid is moved to its closed position.
A further object of the present invention is the provision of an improved lid having a dispenser with a dispensing spout that minimizes dripping.
A further object of the present invention is the provision of an improved washer lid which is comprised of a metal lid frame and a plastic housing detachably connected to the metal frame.
A further object of the present invention is the provision of an improved washer lid having a fluid dispenser therein which is economical to manufacture, durable in use, attractive in appearance, and efficient in operation.
SUMMARY OF THE INVENTION
The foregoing objects may be achieved by a combination of a washing machine cabinet having a top cover thereon. The top cover includes an upwardly presented surface with an access opening therein. A first sloping surface extends downwardly and away from the access opening and a second sloping surface extends downwardly and toward the access opening. A lid is hinged to the top cover for pivotal movement between a closed position in covering relation over the access opening and an open position. A seal member is mounted on the lid and is in sealing engagement with the top cover for preventing fluid or condensation from moving away from the access opening to the first sloping surface of the top cover. The lid may, or may not, have a fluid dispensing chamber on its lower surface.
BRIEF DESCRIPTION OF THE FIGURES OF THE DRAWINGS
FIG. 1 is a perspective view of the present invention.
FIG. 2 is a view similar to FIG. 1, but showing the washer lid in its closed position.
FIG. 3 is a top plan view of the top cover of the present invention showing in phantom lines the position of the sealing gasket when the lid is closed.
FIG. 4 is a sectional view taken along line 4 — 4 of FIG. 2 .
FIG. 5 is a front elevational view taken from the front of the washing machine as viewed in FIG. 1 .
FIG. 6 is a partial sectional view taken along line 6 — 6 of FIG. 5 .
FIG. 7 is a sectional view showing the level of fluid within the reservoir chamber before the dispensing chamber has been charged.
FIG. 8 is a view similar to FIG. 7, but showing the lid in its horizontal position with the fluid passing from the reservoir chamber into the dispensing chamber.
FIG. 9 is a view similar to FIG. 7 and 8 showing the lid returned to its upstanding position with the dispensing chamber being fully charged with fluid.
FIG. 10 is a perspective view of the plastic dispenser housing of the present invention, showing the valve in an exploded view.
FIG. 11 is an enlarged sectional view taken along line 11 — 11 of FIG. 7 .
FIG. 12 is a sectional view taken along line 12 — 12 of FIG. 11 .
FIG. 13 is an exploded perspective view showing the interrelationship of the plastic dispenser housing, mounting bracketry and the metal lid frame.
FIG. 14 is an enlarged exploded view of one corner of the assembly of FIG. 13 .
FIG. 15 is a sectional view taken generally along line 15 — 15 of FIG. 5 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawings the numeral 10 generally designates a clothes washer using a lid assembly 68 having the fluid dispenser of the present invention. Washer 10 includes a cabinet 12 having side walls 14 , a front wall 16 and a top wall 18 . Top wall 18 includes a horizontal portion 20 and an inclined portion 22 which extends downwardly and forwardly from the front edge of the horizontal portion 20 . The top wall 18 is provided by a top cover 24 having a rear edge 26 , side edges 28 , 30 , and a front edge 32 . A juncture or bend 34 divides the horizontal portion 20 from the inclined portion 22 of the top surface of the top cover 24 .
Provided within top cover 24 is a door depression 36 having a rear edge 38 , side edges 40 , 42 and a front edge 43 . Extending upwardly and rearwardly from the front edge 43 is a lip flange 44 having a lower front edge 46 which extends upwardly and rearwardly to a ridge 48 . Ridge 48 includes opposite ends 50 , 52 and an intermediate portion 54 . Intermediate portion 54 is slightly below the ends 50 , 52 and is also positioned forwardly from ends 50 , 52 .
Extending downwardly and inwardly from ridge 48 is a generally circular skirt 56 having a front 7 f drain surface 58 , side drain surfaces 60 , 62 , and a rear drain surface 64 all of which surround an access opening 66 .
Top lid assembly 68 is comprised of a metal lid frame 70 and a plastic dispenser housing 72 which are detachably secured together. Plastic dispenser housing 72 includes a gasket seal 74 (FIG. 1 ), and a fluid chamber formed by a reservoir chamber wall 76 and a dispensing chamber wall 78 . Gasket seal 74 is elongated and includes a left end 96 and a right end 98 . As best shown in FIGS. 1 and 3, gasket seal 74 extends across the front of the washer door depression 36 and generally across the ridge 48 . The gasket seal 74 retains condensation in the area of the door depression 36 and also provides a reduction in agitation noise that otherwise might escape from the access opening 66 of the washer 10 .
A reservoir viewing window 80 is provided in reservoir chamber wall 76 and a dispensing viewing window 82 is provided in dispenser chamber wall 78 . A sliding indicator or gage 84 is mounted on a track associated with window 82 and is operable for movement along the length of the dispenser viewing window 82 . The sliding indicator 84 can be manually set as a marker at any of a plurality of positions along the length of the window 82 . Plastic dispenser housing 72 also includes a fill cap 86 which is detachably mounted over a fill opening 87 and a dispenser button 88 for dispensing fluid 90 from the dispensing chamber in a manner to be described in more detail hereafter.
Metal lid frame 70 includes a horizontal surface 92 (when the lid is in its closed position) and an inclined surface 94 .
Behind reservoir chamber wall 76 is a reservoir chamber 100 (FIG. 4 ), and behind dispenser wall 78 is a dispensing chamber 102 (FIG. 7 ). Dispensing chamber 102 is contained within reservoir chamber 100 and includes side walls 104 , a rear wall 106 , and a dispenser spout 108 which provides a dispenser opening for permitting fluid to exit from dispenser chamber 102 . The portion of the dispensing chamber 102 formed by walls 104 and 106 is attached to front wall 76 by an interference fit and a slight amount of fluid can leak by the attachment point.
Within reservoir chamber 100 are several stand offs 110 , 112 which provide structural support to the walls within the reservoir chamber 100 .
Referring now to FIG. 15, the fill opening 87 is shown without fill cap 86 in place. With the lid assembly 68 in the generally vertical posture of FIGS. 1 and 5, the fill opening 87 is formed with a downwardly angled entry portion 89 through wall 76 and a substantially horizontally disposed cylindrical exit portion 91 . The back edge 93 of the exit portion 91 is in close proximity to and generally parallel to the back wall 99 of the reservoir chamber 100 . When fluid is poured into the fill opening 87 , it will flow into the exit portion 91 and will enter the reservoir chamber 100 . The fill can continue until fluid is observed at the lower lip of exit portion 91 at which point the reservoir chamber 100 is full. When the lid assembly 68 is in the closed horizontal posture of FIG. 4, the fluid in the reservoir chamber 100 will always be below the back edge 93 of the exit portion 91 . Thus, if the operator should forget to replace the fill cap 86 , there would not be any spilling of fluid out the fill opening 87 . In fact, fill cap 86 could be left off if desired. Further shown in FIG. 15 is a vent opening 101 that allows the reservoir chamber 100 to breath freely preventing any airlock condition.
Plastic housing 72 is nested within the metal lid frame 70 and is fitted beneath the curled front edge 114 . The peripheral edges of the housing 72 rest on the side edges 144 , 146 (FIG. 13) and rear edge 148 of the metal lid frame 70 . The front edge 116 of the plastic housing 72 nests under the front curled edge 114 of the lid frame 70 .
Referring to FIGS. 10 and 11, a valve assembly 117 comprises a valve stem 118 having an upper end 120 . Dispenser button 88 is fitted over the upper end 120 and includes a sealing flange 122 thereon. Valve stem 118 includes a valving flange 124 and a retaining flange 126 . A coil spring 128 is fitted over the lower end of the valve stem 118 . The valve assembly 117 is fitted within a valve receiving bore 130 in the housing 72 . A retaining clip 132 is fitted within a retaining clip slot 134 and includes clip fingers 136 (FIG. 12) which retentively engage the retaining flange 126 to hold the valve assembly 117 within valve receiving bore 130 . The clip fingers 136 of retaining clip 132 are yieldably movable toward one another to permit the clip 132 to be removed so as to permit removal of the valve assembly 117 . This permits the easy removal of the valve assembly 117 for cleaning.
Referring to FIG. 11 a dispenser port 138 provides communication from dispensing chamber 102 to the valve receiving bore 130 . Fluid is permitted to enter the axial space between the valving flange 124 and the sealing flange 122 . Depression of button 88 causes the valving flange 124 to move to the left of the dispenser spout 108 as viewed in FIG. 11 thereby permitting fluid to flow out of the dispenser spout 108 . Removal of pressure from the button 88 permits the spring 128 to return the valve flange 124 to its original position, thereby cutting off the flow of fluid from the dispenser chamber 102 .
FIGS. 7, 8 , and 9 illustrate the method of using the dispenser chamber 102 and the reservoir chamber 100 of the present invention. Initially the lid assembly 68 is moved to its up-standing position shown in FIG. 7 . The fill cap 86 is removed and fluid such as liquid detergent is poured into the reservoir chamber 100 until fluid is observed at the lower lip or exit portion 91 of the fill opening 87 . As can be seen in FIG. 6, the front walls 76 , 78 of the chambers 100 , 102 are inclined toward the dispensing chamber 102 thereby causing any fluid within chamber 100 to move toward the dispensing chamber 102 when the lid assembly 68 is lowered.
As can be seen in FIG. 7 the initial filling of the reservoir chamber 100 does not cause any substantial amount of fluid to be within the dispensing chamber 102 . However, when the lid assembly 68 is moved to its closed position (FIG. 8) the fluid within chamber 100 flows around the rear wall 106 and both of the side walls 104 of chamber 102 and enters chamber 102 through a charging opening 107 adjacent the rear wall 106 . Returning the lid assembly 68 to its upright position as shown in FIG. 9 causes the dispenser chamber 102 to be full and ready for dispensing fluid through spout 108 .
The operator then depresses the button 88 and observes through window 82 as the fluid level lowers within dispenser chamber 102 . The operator can determine, by dispensing a predetermined quantity of fluid into a measuring container, what the level of the fluid within the dispensing chamber should be after the proper amount has been dispensed. The operator can then move the sliding indicator 84 to mark that position and thereafter can release the button 88 when the level of fluid reaches the level of the sliding indicator 84 . Thus, the sliding indicator 84 is set to the proper level for a particular brand or concentration of detergent.
On occasion the detergent may clog or foul the valve assembly 117 . This can easily be remedied by pulling out clip 132 and removing the valve assembly for cleaning. The valve assembly 117 can then be reinserted, and the clip 132 is inserted to retain the valve assembly 117 in position for operation.
Referring to FIGS. 13 and 14, the present invention utilizes a novel means for attaching the plastic housing 72 to the metal lid frame 70 . Two L-shaped brackets 140 , 142 are fitted in the rear corners of the metal lid frame 70 under the edges 144 , 146 , 148 as shown in FIGS. 13 and 14. L-shaped brackets 140 , 142 are each provided with elongated slots 150 and are also provided with a bushing 170 which fits within a spring hole 172 of the metal lid frame 70 . Bushing 170 includes a cylindrical bore extending therethrough and a torsion rod spring 152 is fitted through the bore in bushing 170 . Torsion rod spring 152 includes a first end 154 and a second end 156 (FIG. 13 ). The second end 156 engages the L-shaped bracket 140 , and the first end 154 is outside the top lid assembly 68 and is adapted to engage the underside of top cover 24 to provide a counter balance to the lid assembly, counter balancing the weight provided by the fluid in the reservoir and dispensing chambers 100 and 102 .
A center link clamp 158 is clamped over the torsion rod spring 152 between the two L-shaped brackets 140 , 142 so as to lock the L-shaped brackets beneath the curled lip flanges 144 , 146 on the sides of metal lid frame 70 . The spring 152 is held to the L-shaped brackets 140 , 142 and the center link clamp 158 by spring finger clamps 174 .
Four retainer pegs 160 each include a slot 162 , a shank 164 and an elongated tab 166 . These pegs 160 are fitted within holes 168 in housing 72 and the elongated tabs 166 fit within the elongated slots 150 of the L-shaped brackets 140 , 142 . Rotation of the pegs 160 causes the elongated tabs 166 to turn below the slots 150 so as to retentively attach the housing 72 within the metal lid frame 70 . This attachment of the housing 72 to the frame 70 allows quick removal of the housing 72 so that it may be taken to a sink for flushing or cleaning should it become clogged by liquid detergents or their residue. Further, the unique system for attachment of the housing 72 to the lid frame 70 allows the housing 72 to be easily installed as an accessory since the same lid frame is used with or without the housing 72 .
In the drawings and specification there has been set forth a preferred embodiment of the invention, and although specific terms are employed, these are used in a generic and descriptive sense only and not for purposes of limitation. Changes in the form and the proportion of parts as well as in the substitution of equivalents are contemplated as circumstances may suggest or render expedient without departing from the spirit or scope of the invention as further defined in the following claims. | A washing machine includes a washing machine cabinet having a top cover thereon. The top cover has an upwardly presented surface with an access opening therein and a first sloping surface extending downwardly and away from the access opening. A lid has a seal member thereon which engages the top cover for preventing fluid or condensation from moving away from the access opening down the first sloping surface of the top cover. | 3 |
The present application claims priority to the Jul. 21, 2008 filing date of U.S. provisional patent application Ser. No. 61/082,311.
FIELD OF THE INVENTION
The present invention is addressed to more precisely feeding yarns for sewing fabrics, and is especially adapted to the feeding of yarns that are pneumatically supplied for tufting, as via a hollow needle.
BACKGROUND OF THE INVENTION
In most hollow needle tufting machines, as typified by Kile, U.S. Pat. No. 4,549,496; Davis, et al., U.S. Pat. No. 5,588,383 and Ingram, U.S. Pat. No. 7,318,383, yarns are selectively fed to hollow needles by pneumatic pressure. Where the yarn being fed to a particular needle is changed, Kile and Davis found it necessary to retract the previously fed yarn from the hollow needle and to pneumatically urge the newly selected yarn to extend through the hollow needle to the appropriate length for tufting. Due to the characteristics of yarns and the imprecise nature of pneumatically supplied yarn, the lengths of yarns tufted are generally not uniform and the resulting fabrics not only require tip shearing but also result in the waste of substantial amounts of yarn.
Accordingly, the need exists to obtain more uniform stitch height with pneumatically fed yarns. Due to the elasticity of yarns, when tension is released from a yarn being fed for tufting, there is a contraction of yarn length. Different yarns have differing elasticities so the contraction is not precisely controllable. Furthermore, the amount of contraction varies with the length of yarn that has been placed under tension. Therefore, a need exists to provide for the provide for the feeding of yarns, and particularly the pneumatic feeding of yarns, in a fashion where only a relatively short length of yarn is placed under tension when the yarn is fed. In this fashion, the contraction of the yarn will be limited when the tension is released.
Additionally, even in the case of yarns fed by conventional means, varying yarn elasticity contributes to less uniform output. For instance, varying tension in pulling yarns from a yarn supply, and the release of tension after yarns are cut or otherwise released from a hook or looper, may cause different yarns to produce yarn bights of different heights.
Furthermore, some pneumatic yarn feeds are designed to constantly urge yarns to their associated hollow needles. In the absence of a tensioning device, the yarns will be fed at an incremental rate toward the hollow needle. Therefore, a need exists to prevent the slippage of yarns that are not selected for the current stitch.
SUMMARY OF THE INVENTION
In order to accomplish these and other objects of the invention, an improved yarn feed control is provided with the teethed yarn puller wheels to positively grip and feed yarns. A yarn tensioning and clamping device is also provided that serves to keep yarns under tension while those yarns are being fed for tufting and that clamps the yarns when yarn feed tension is relaxed so that only a limited length of yarn may contract, and so that there is no slippage of yarns that are not selected for tufting.
BRIEF DESCRIPTION OF THE DRAWINGS
The particular features and advantages of the invention as well as other objects will become apparent from the following description taken in connection with the accompanying drawings in which:
FIG. 1 is a perspective view of a gear housing assembly with yarn clamping and yarn feed control components.
FIG. 2 is a partially exploded perspective view of the gear housing assembly of FIG. 1 .
FIG. 3 is a side plan view of the gear housing assembly of FIG. 1 mounted to the head of a tufting machine and engaged with a driven yarn feed roll.
FIG. 4 is a side plan view of the gear housing assembly of FIG. 1 mounted to the head of a tufting machine in a position clamping a yarn against a tension bar.
FIG. 5 is a side sectional view of an array of gear housing assemblies attached to a tufting machine head.
FIG. 6 is a perspective view of a pattern control yarn feed system comprising an array of gear housing assemblies and driven yarn feed rolls.
DETAILED DESCRIPTION OF THE INVENTION
In FIGS. 1 and 2 a gear housing assembly 10 designed to provide precise yarn feed and yarn tensioning control is illustrated. The principal elements of gear housing assembly 10 are coupling pins 24 , weight block 20 , mounting bar 11 , and teethed yarn roll 36 . These elements are carried in a structure comprising first side plate 16 and second side plate 17 with fasteners 31 that are received in fastener openings 30 located in top fastening block 25 , second fastening block 26 , third fastening block 27 , and bottom fastening block 28 . In addition, some fasteners 31 are received within openings 30 a in bearing support 35 .
Turning then to the principal features of the gear housing assembly 10 , the coupling pins 24 extend upwards and operate in conjunction with a clevis 47 and clevis pin 48 illustrated in FIGS. 3 and 4 to apply pressure at the top of the gear housing assembly on coupling pins 24 . Mounting bar 11 has vertical openings 12 which, as shown on FIGS. 3 and 4 , receive fasteners 32 to mount the gear housing assembly 10 on the manifold beam 40 which, as shown in FIGS. 5 and 6 , is in turn mounted in a frame 61 of pattern control yarn feed attachment 60 that is mounted to the head 62 of a tufting machine. At the end of the mounting bar 11 opposite the vertical openings 12 is a rounded end 13 and a lateral opening 14 that receives bearing pin 15 extending between the first side plate 16 and second side plate 17 and being received in plate opening 18 on the first side plate 16 and a similar opening in second side plate 17 as shown in FIGS. 1 and 2 . The rounded end 13 permits the structure held by the first side plate 16 and second side plate 17 to rotate about 10 degrees in either direction. The slots 19 in cooperation with the lateral pins 21 permit the weight block 20 to move slightly forward and rearward relative to the first side plate 16 and second side plate 17 . The weight block 20 has at one end a yarn clamping area such as notch 23 . The gear housing assembly 10 also has a series of yarn guiding features such as apertures 29 in fastening blocks 25 , 26 , 27 , 28 and yarn guide pins 22 on weight block 20 .
In FIG. 3 , the gear housing assembly 10 is illustrated in operation to provide precise increments of yarn to associated needles. On support manifold 40 at the bottom is secured the mounting bar 11 of gear housing assembly 10 . Within the manifold are pressurized air conduits 49 that convey pressurized air to electronically controlled valves, not shown, that selectively supply air pressure to ports 43 , 44 of air cylinder 42 . On the top of support manifold 40 is L bracket 41 which has an opening to receive the forward end of cylinder 42 . The forward end of cylinder 42 is threaded and fastened in place by securing bolt 45 on the opposite face of L bracket 41 . Air cylinder 42 is preferably a double acting cylinder with air supplied to port 44 to retract the cylinder shaft 46 , shown in FIG. 4 . Conversely, pressurized air is supplied to port 43 to drive the cylinder shaft 46 forward.
In FIG. 3 , the gear housing assembly 10 is shown with pressurized air having been supplied to port 44 so that cylinder shaft 46 is entirely retracted and clevis 47 is in proximity to cylinder mounting bolt 45 . Clevis pin 48 is positioned between coupling pins 24 and has moved the top portion of gear housing assembly 10 closer to the tufting machine head 62 while the bottom portion of gear housing assembly 10 carrying yarn roll 36 has pivoted about bearing pin 15 to extend outward and engage its teeth with the teeth of driven yarn roll 37 mounted on drive shaft 38 . The yarn 34 being fed from yarn supply, not shown, through vertical yarn guide openings 29 in fastening blocks 25 , 26 , 27 and 28 is carried between the interfitting teeth of yarn roll 36 and driven yarn roll 37 and securely gripped. In this fashion, a precise increment of yarn is advanced by the rotation of drive shaft 38 and corresponding driven yarn roll 37 .
It will also be seen that a stationary clamping member such as tension bar 51 is mounted with fastener 52 to angle 50 that connects back to support beam 40 . When the upper portion of gear housing assembly 10 is retracted toward the tufting machine head 62 as illustrated in FIG. 3 , the lateral pins 21 of weight block 20 are positioned in intermediate portions of slots 19 so that the yarn 34 passing through notch 23 is tensioned only by the weight of block 20 . This allows the yarn to advance, when pulled by driven yarn roll 37 but the yarn advances in a tensioned state so that the longitudinal elasticity of the yarn is slightly expanded. Furthermore, in the course of feeding yarn from the yarn supply, there are occasional variations in tension as when yarn unwinding from a spool snags and then releases suddenly. The sudden release of tension sends a wave of excess yarn from the yarn supply to the pattern control yarn mechanism. The pressure provided by weight block 20 is sufficient to prevent the excess yarn 34 from feeding prematurely toward the needles.
In FIG. 4 , pressurized air is supplied to port 43 of double acting air cylinder 42 so that cylinder shaft 46 is extended and the top portion of gear housing assembly 10 is moved away from the tufting machine head. The lower portion of gear housing assembly 10 carrying yarn roll 36 is pivoted about bearing pin 15 to move closer to tufting machine and out of engagement with driven yarn roll 37 so that yarn 34 is no longer advanced. However, it can be seen at the upper end of gear housing assembly 10 that the lateral pins 21 of weight block 20 are at the upper most pins of slots 19 in first side plate 16 so that the pressure brought on yarn 34 as it passes through notch 23 is not merely the weight of block 20 , but is instead the pressure applied by the action of pressurized gas through port 43 in air cylinder 42 . The yarn can thereby be pinched relatively securely between tension bar 51 and the yarn clamping portion of weight block 20 , namely in the notch 23 of the illustrated embodiment.
Therefore, in operation, a gear housing assembly 10 is provided for each yarn that is being fed to a needle on the associated tufting machine. In the case of a hollow needle tufting machine, this generally means that six or eight gear housing assemblies are provided for each needle to feed the yarns downward into funnel slots such as are disclosed in Ingram, U.S. Pat. No. 7,318,383. To provide adequate space for this number of gear housing assemblies, yarns may be supplied from both the front and rear side of the tufting machine. In the case of a hollow needle tufting machine with eight yarns supplied to each of the funnel slots, it would typically be advantageous to mount four gear housing assemblies 10 on each side of the tufting machine. When the tufting machine is in operation, only one of the eight gear housing assemblies will be in the yarn advancing position illustrated in FIG. 3 and the remaining seven gear housing assemblies would be in the yarn clamping position illustrated in FIG. 4 . When it is desired to switch the yarn being supplied to the associated needle, the gear housing assembly 10 in the yarn supplying configuration of FIG. 3 is operated by the application of air pressure to port 43 of air cylinder 42 to disengage yarn 34 and yarn roll 36 from the driven yarn roll 37 and to simultaneously clamp the yarn 34 between the tension bar 51 and weight block 20 . The action of the weight block 20 and the clamping action performs two functions that appear to improve the preciseness of the yarn feed: (1) to prevent the elasticity of the yarn between the yarn supply and the yarn clamping area 23 to substantially alter the length of yarn that has already passed between the position of the yarn rolls; and (2) to prevent the unintended advancement of yarns either by the reciprocating motion of the hollow needle assemblies or by the pneumatic urgings applied to the yarns generally so that they feed freely from the yarn supply to the needles.
When the yarn being supplied to needles is changed, just as the gear housing assembly 10 of the previously supplied yarn is rotated out of the supplying position of FIG. 3 , the gear housing assembly 10 of the newly selected yarn is rotated from the clamping position of FIG. 4 to the yarn supplying position of FIG. 3 by the application of pneumatic pressure through port 44 of double acting cylinder 42 . The yarn 34 is unclamped and advanced by the positive cooperation of driven yarn roll 37 and yarn roll 36 . Due to the clamping action between tension bar 51 and notch 23 of weight block 20 , the only length of yarn not already tensioned when the yarn advancement begins is the length of yarn between the yarn clamping point 23 and the mating gear teeth of yarn rolls 36 , 37 . In this fashion, the operation of gear housing assembly 10 facilitates relatively precise metering of yarns to hollow needles and minimizes height irregularities in the resulting tufted fabrics. This results in less wasted yarn and the ability to produce a finished product with limited tip shearing so that the tufting height of the yarns can be only slightly greater than the intended height of the finished tufted carpets.
Furthermore, the effectiveness of the present yarn control system is such that in the context of a tufting machine with yarns fed by pneumatic pressure to hollow needles, in step of yarn retraction is not required. Instead, the leading end of the yarn after being cut is allowed to remain within the hollow needle. Due to the elasticity of the yarn, there may be a slight retraction of the leading end of yarn from the open tip of the hollow needle after the fed yarn is cut, however, the secure clamping of unfed yarns allows the leading ends of those yarns to remain within the hollow needle without resulting in subsequent underfeeding or overfeeding of the yarns.
In FIGS. 5 and 6 , an array of gear housing assemblies 10 are illustrated in a frame 61 optimized to supply six yarns to each hollow needle. The frame 61 is mounted to the head 62 of a tufting machine. A manifold 82 is provided to convey pressurized gas across the width of the tufting machine. The pressurized gas is provided from ports 81 of manifold 82 to ports 83 of the support manifolds 40 and thence through electronically activated valves to air supply ports 43 , 44 . To complete the array of FIG. 6 , preferably independently operable servo motors would be associated with each drive shaft 38 for the driven yarn rolls 37 . Both the servo motors and electronically activated air valves are controlled by an electronic controller interpreting pattern data and supplying control commands via electronic signals distributed across an appropriate controller network
All publications, patent, and patent documents mentioned herein, and particularly Davis, et al., U.S. Pat. No. 5,588,383 and Ingram, U.S. Pat. No. 7,318,383, are incorporated by reference herein as though individually incorporated by reference. Although preferred embodiments of the present invention have been disclosed in detail herein, it will be understood that various substitutions and modifications may be made to the disclosed embodiment described herein without departing from the scope and spirit of the present invention as recited in the appended claims. | A yarn tensioning apparatus is supplied with a yarn clamping position and a positive yarn engaging position to precisely meter yarns to tufting machine needles and especially to more uniformly advance pneumatically supplied yarns to hollow needles. | 3 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention is relative to single phase AC to DC converter with power factor correction function (so that the power factor of the input current is at a power factor in excess of that of an otherwise comparable low-power-factor converter design). It can be used on in switching mode power supply and electronics ballast.
[0003] 2. Description of the Proir Art
[0004] The demand for and development of power factor correction (PFC) circuit has been fueled by a concern over the massive use of electronics power converter, such as, AC-DC-DC, AC-DC-AC employed in switching mode power supply system. Due to cost and efficiency consideration, it is desirable to employ a simple PFC circuit and increase the efficiency of the whole system.
[0005] PFC circuits are classified into two groups. First group is defined as active PFC circuits, and second group is defined as passive PFC circuits. The very popular Boost-type PFC circuit is an active PFC circuit. It can shape the input current and make the total harmonic distortion (THD) very low. However, the efficiency of the active PFC circuit is lower than one of passive PFC circuit, due to extra switching circuit. Further, the control of the active PFC is complicated, resulting in increased manufacturing cost and reduced reliability of the circuit. For passive PFC circuit, due to no active control switch in the circuit, the passive PFC can work in higher efficiency, but THD of the passive PFC is higher and size of the passive components is big.
[0006] Based on the advantage and disadvantage of two groups PFC circuits, the concept of single power stage converter with PFC was presented for several years. In the converter, some extra passive components are added to a regular converter. The extra components are working in the converter's switching frequency. The size of the extra component is small due to higher operating switching frequency. In this kind of converter, the main task of the active switch of the converter is to regulate the output power. The active switch involves a part of task to shape the input current. Due to both input and output current controlled by the active switch, the loss on the active switch is higher and the efficiency of the whole system is lower.
[0007] Based on the existed PFC circuits, there are a lot of papers and patents about valley-fill circuit. The basic valley-fill circuit is shown in FIG. 1. Valley-fill circuit can provide better performance than other passive types of PFC circuits.
[0008] In the valley-fill circuit, the power line directly feeds energy (e.g. electrical energy) to the load through the rectifier diodes for approximately 120 degrees around the peek voltage. Two storage capacitors C 1 and C 2 feed energy to the load through diodes D 1 and D 2 for approximately 60 degrees near the zero line crossing points. Most of the input energy being first fed to the load, with a small portion of the input energy being first fed to the two storage capacitors C 1 and C 2 , and then fed to the load through capacitors C 1 and C 2 . As a result, such a circuit offers a relatively high operating efficiency.
[0009] Problems with the valley-fill circuit are a pulsating line current charges the capacitors near the peak power line voltage, resulting in a deteriorated PF (of about 0.95) and a high THD (e.g. about 40%). The output of the valley-fill circuit exhibits a large ripple from the half of the power line peak voltage to the power line peak voltage, with the ripple frequency being equal to twice the line frequency.
[0010] A great deal of the time and effort has been spent in attempts to improve the PFC performance of the valley-fill circuit. This work has been directed to shaping the input current during the approximate 60 degree dead time near the zero line crossing points, and to limiting the pulsating line current that charges the capacitors near the peak line voltage.
[0011] A paper titled “A Unity Power Factor Electronic Ballast for Fluorescent Lamp Having Improved Valley Fill and Valley Boost Converter” from Conference Record PESC'97, describes the use of an active boost circuit to shape the input current during the approximate 60 degree dead time near the zero line crossing points, as shown in FIG. 3. Because a boost switch still suffers the peak input voltage and the switch only works during the 60 degree dead time, as shown in FIG. 4, a complex control method is required to detect the operating point. In addition, the complexity of the circuit decreases the reliability and increases the total manufacturing cost.
[0012] Japanese Pat. No. HEI 8-205520 illustrated in FIG. 5, describes the load current of a PFC converter as being discontinues, and discloses that the insertion of a suitable inductor L 1 in the input power line avoids pulsating of the power line current. Because an instantaneous line voltage is higher than the voltage of each DC bulk capacitor C 1 and C 2 , while being less than the sum of the voltages of the two capacitors, the inserted inductor provides a boost function to boost the sum of the voltage of the two capacitors. However, this disclosure fails to solve the above-described problem that exists at the input current during the approximate 60 degree dead time near the zero line crossing points.
[0013] U.S. Pat. No. 5,986,901 illustrated in FIG. 6, discloses the use of the high frequency discontinues input current of the converter to drive a charge pump circuit Z and the inserted input inductor. As shown in FIG. 6, the charge pump circuit shapes the input current during the approximate 60 degree dead time, and the input inductor provides a boost function to boost the sum of the voltage of the two capacitors. Because the charge pump circuit and the inserted input inductor are driven with the discontinues input current automatically, the active switch or switches in the converter would not be exposed to extra current or voltage stresses. However, the disclosure needs several passive components to implement the charge pump circuit. The cost of the disclosure is still high.
SUMMARY OF THE INVENTION
[0014] Accordingly, the present invention is based on a valley-fill circuit, but the 60 degree dead time and the pulsating current of the valley-fill PFC circuit are eliminated, while maintaining a high operating efficiency. According to the instant invention, a driving source of an auxiliary PFC circuit, such as, for example, a couple inductor circuit, is coupled from at least one leg of a valley-fill PFC circuit, so as to shape the input current during the approximate 60 degree dead time near the zero line crossing points. In addition, a couple-inductor circuit is employed to reduce (or eliminate) the power line's pulsating line current and to help boost performance of an auxiliary PFC.
[0015] The present invention enables one to avoid the use of active switch and control circuit for a PFC while keeping the advantages of a passive PFC circuit; namely, high efficiency, resulting in a lowered manufacturing cost. The PFC function automatically acts when the line voltage is less than the voltage on a pair of the storage capacitors.
[0016] According to the present invention, a power factor correction circuit is disclosed and includes a system that shapes an input current of a power line during predetermined period proximate a zero line crossing point of the input current, and a system that minimizes a pulsating of the input current. According to an advantage of the instant invention, an output of the power factor correction circuit is provided to a discontinues power source, such as, for example, a discontinues current load that is suitable for most power converter circuits as a following power stage, a discontinues current input buck converter, a discontinues current input full bridge converter, a discontinues current input full bridge inverter, a discontinues current input half bridge converter, a discontinues current input half bridge inverter, or a discontinues current input buck-boost converter, a discontinues current input flyback converter.
[0017] According to an advantage of this invention, the couple inductor circuit comprises multi-winding couple inductors on one magnetic core. One winding of the couple inductors is connected between the output of the rectifier and the valley-fill circuit as well as the output load of the valley-fill PFC converter. At least a second winding of the couple inductors is connected to at least one DC bulk storage capacitance device of the valley-fill PFC converter. In this way, the current released from the DC bulk storage capacitance device of the valley-fill PFC converter can be stored in magnetic energy in the couple inductors and as the output load current of the valley-fill PFC converter is zero, that is, discontinues, the energy stored in the couple inductors will release to the two DC bulk storage capacitance devices of the valley-fill PFC converter and other energy storage device through the rectifier and input AC line of the valley-fill PFC converter during the approximate 60 degree dead time.
[0018] According to an object of the instant invention, a switching power supply is disclosed having an AC-to-DC converting device that converts an AC input line voltage to a DC voltage, an energy storage device (such as, for example, a valley-fill circuit and other energy storage device) that stores electrical energy in which the stored energy is released to a load during a predetermined period of the AC input line voltage, and an auxiliary power factor corrector that operates, upon a release of the electrical energy (such as, for example, a high frequency discontinues current), stored in the energy storage device, to shape the AC input line current during the predetermined period. The predetermined period comprises a period proximate a zero voltage crossing of the AC input voltage.
[0019] According to an advantage of the instant invention, a device which limits the current slew rate is provided that limits a current input slew rate of the AC-DC converter device.
[0020] According to another advantage of the present invention, the current slew rate limiting device comprises an electromotive force generator, such as, for example, the couple inductors.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] [0021]FIG. 1 illustrates a conventional basic valley-fill power factor correction circuit.
[0022] [0022]FIG. 2 illustrates electrical waveforms of an input current and an output voltage of the valley-fill power factor correction circuit of FIG. 1.
[0023] [0023]FIG. 3 illustrates a prior art valley-fill power factor correction circuit AC-DC-AC converter that employs an active boost circuit to shape an input current during a 60 degree dead time proximate a zero line crossing.
[0024] [0024]FIG. 4 illustrates electrical waveforms produced by the valley-fill power factor correction circuit of FIG. 3, in which the top waveform represents a DC bulk voltage, the middle waveform represents an input current, and the bottom waveform represents a switch driving signal.
[0025] [0025]FIG. 5 illustrates a prior art valley-fill power factor correction circuit employing an input electromotive force generating device to avoid pulsating of the power line current.
[0026] [0026]FIG. 6 illustrates a block diagram of prior art valley-fill power factor correction circuit employing a charge pump circuit to shape an input current during a 60 degree dead time proximate a zero line crossing and avoid pulsating of the power line current.
[0027] [0027]FIG. 7 illustrates a block diagram of quasi active power factor correction AC-DC converter according to a preferred embodiment of the instant invention.
[0028] [0028]FIG. 8 illustrates an electrical circuit diagram of a single phase high power factor correction converter with discontinues current load according to the preferred embodiment of the present invention.
[0029] [0029]FIG. 9 illustrates an electrical circuit diagram of a second embodiment of the present invention, showing a single phase high power factor correction converter with discontinues current input buck converter.
[0030] [0030]FIG. 10 illustrates an electrical circuit diagram of a third embodiment of the present invention, showing a single phase high power factor correction converter with discontinues current input full bridge inverter.
[0031] [0031]FIG. 11 illustrates an electrical circuit diagram of a fourth embodiment of the present invention, showing a single phase high power factor correction converter with discontinues current input half bridge inverter.
[0032] [0032]FIG. 12 illustrates an electrical circuit diagram of a fifth embodiment of the present invention, showing a single phase high power factor correction converter with discontinues current input buck-boost converter.
[0033] [0033]FIG. 13 illustrates an electrical circuit diagram of a sixth embodiment of the present invention, showing a single phase high power factor correction converter with discontinues current input Flyback converter.
[0034] [0034]FIG. 14 illustrates an electrical circuit diagram of a seventh embodiment of the present invention, showing a single phase high power factor correction converter with discontinues current input forward converter.
[0035] [0035]FIG. 15 illustrates an electrical circuit diagram of a eighth embodiment of the present invention, showing a single phase high power factor correction converter with discontinues current input two switches forward converter.
[0036] [0036]FIG. 16 illustrates an electrical circuit diagram of a ninth embodiment of the present invention, showing a single phase high power factor correction converter with discontinues current input two switches flyback converter.
[0037] [0037]FIG. 17 illustrates an electrical circuit diagram of a tenth embodiment of the present invention, showing a single phase high power factor correction converter with discontinues current input half bridge DC-DC converter.
[0038] [0038]FIG. 18 illustrates an electrical circuit diagram of a eleventh embodiment of the present invention, showing a single phase high power factor correction converter with discontinues current input full bridge DC-DC converter.
[0039] FIGS. 19 to 28 illustrate the modified topologies shown in FIG. 9 to FIG. 18, that is, the low pass filters are shifted from AC side to DC side.
[0040] [0040]FIG. 29A illustrates simulation waveforms of input line voltage and current associated with a Flyback converter employed in the embodiment of FIG. 13
[0041] [0041]FIG. 29B illustrates simulation waveforms of couple inductor L 1 current and the output voltage associated with a Flyback converter employed in the embodiment of FIG. 13.
[0042] [0042]FIG. 30A illustrates simulation waveforms of input line voltage and current associated with a Forward converter employed in the embodiment of FIG. 14
[0043] [0043]FIG. 30B illustrates simulation waveforms of couple inductor L 1 current and the output voltage associated with a Forward converter employed in the embodiment of FIG. 14.
[0044] [0044]FIG. 31 illustrates a modified topology of FIG. 8.
[0045] [0045]FIG. 32 illustrates a modified topology of FIG. 8, but the low pass filter is shifted from AC side to DC side
DETAILED DESCRIPTION OF THE INVENTION
[0046] The present invention discloses a passive PFC circuit that exhibits a high operating efficiency. A block diagram of a preferred embodiment is shown in FIG. 7. As shown in the drawing, a driving source of an auxiliary PFC circuit Z such as, for example, a couple-inductor is coupled from at least one leg of the valley-fill circuit to shape the input current during the 60 degree dead time near the zero line crossing points. Thus, the present invention, in its most basic form, overcomes the above noted problems of the prior art; namely, the existence of the approximate 60 degree dead time and the pulsating current of valley-fill PFC circuit as well as complicated circuit.
[0047] As shown in FIG. 7, the load of PFC converter comprises a discontinues current source that exhibits a minimum dead time. During the dead time, the load current is zero or negative. The auxiliary PFC's driving source is coupled from at least one leg of the valley-fill circuit. The leg (or legs) is (are) composed of a pair of diodes and a pair of DC bulk capacitors. In the preferred embodiment, the driving source couple from the legs is a high frequency unipolar current source due to the series diodes.
[0048] [0048]FIG. 8 illustrates a circuit of the preferred embodiment of the present invention. As shown in FIG. 8, the preferred embodiment of the present invention comprises a differential filter made up of inductor Lf and capacitor Cf a bridge rectifier BR, an inserted electromotive force generating device (such as, for example, a couple inductor C_Inductor with three windings L 1 , L 2 and L 3 ), three valley-fill diodes D 1 , D 2 and D 3 , two DC bulk capacitors C 1 and C 2 , a resonant capacitor Cr and a discontinues power source, such as, for example, a buck, a buck-boost, a forward, a flyback, a resonant inverter circuit, or any other equivalent discontinues power load.
[0049] The auxiliary PFC circuit comprises the couple inductor with three windings. The couple inductor's windings couple the driving source from the legs of the valley-fill circuit to shape the input current through the couple inductor's magnetic field. The couple inductor is also used to limit (minimize) the slew rate of the pulsating current and to serve as a boost function to help PFC performance.
[0050] It is noted that the discontinues power (current) load is generated by the switching converter, such as, for example, a buck converter, a buck-boost converter, a flyback converter, a forward converter, a resonant converter, or any other type of switching converter.
[0051] The operation of the preferred embodiment will be described with respect to two working (operating) modes; a direct feed mode (corresponding to a situation in which an instantaneous input line voltage is higher than the voltage of each DC bulk capacitor C 1 and C 2 ), and a couple boost mode (corresponding to a situation in which an instantaneous input line voltage is lower than the voltage of each DC bulk capacitor C 1 and C 2 ).
[0052] The following discussion will be based on an input AC voltage during a positive period. The operation during a negative period is basically the same.
[0053] 1. Direct Feed Mode:
[0054] For the direct feed mode, the output voltage of the rectifier bridge is higher than the voltage on each DC bulk capacitors C 1 and C 2 , but less than the sum of voltage on each DC bulk capacitors C 1 and C 2 . As the PFC's load current is changed from zero to a fixed value, the input line will directly feed the energy to the load and the resonant capacitor Cr through C_inductor's winding L 1 and the rectifier. Because the load current passes through L 1 and the bridge rectifier BR, there is energy stored in L 1 . As the load current is changed from the fixed value down to zero, the energy stored in L 1 will release to the resonant capacitor Cr and two DC bulk capacitors C 1 and C 2 in series through D 3 . Because the input power line is series with L 1 , the input power line charges the resonant capacitor Cr and two DC bulk capacitors C 1 and C 2 through L 1 . Because the output voltage of bridge rectifier is less than the sum of voltage on two DC bulk capacitors, the charging current in L 1 will decay. For the direct feed mode, each switching period can be divided as two intervals. During the first interval, the input power line will directly feed the energy to the load and store the energy in L 1 . During the second interval, the input power line will charge the resonant capacitor Cr and two DC bulk capacitors through C_Inductor's winding L 1 and D 3 .
[0055] 2. Couple Boost Mode:
[0056] In the couple boost mode, the input AC voltage is lower than the voltage on each DC bulk capacitors. Because the input AC voltage is lower than the voltage on each DC bulk capacitors, as the load current is changed from zero to a fixed value, the resonant capacitor Cr releases the stored energy and the voltage on Cr decreases. As the voltage on Cr is less than one on two DC bulk capacitors, the two DC bulk capacitors C 1 and C 2 will release the stored energy to the load and the resonant capacitor Cr in parallel. The current passes through two windings L 2 and L 3 of the couple inductor C_Inductor. It is couple inductor windings that energy is stored in the couple inductor C_Inductor. It is couple inductor C_Inductor that resonates with the resonant capacitor Cr.
[0057] As the load current changes from the fixed value down to zero, the couple inductor windings L 2 and L 3 keep to resonate with Cr. The voltage on Cr increases. As the couple inductor winding L 1 's reflected voltage is higher than two windings L 2 and L 3 's reflected voltages, diodes D 1 and D 2 turn off and the stored magnetic energy in the couple inductor is transferred from the windings L 2 and L 3 to the winding L 1 . The couple inductor C_Inductor will release the stored magnetic energy to the resonant capacitor Cr through C_Inductor's winding L 1 . And at the same time, the input power line will also release or feed energy to the resonant capacitor Cr. In the couple boost mode, each switching period can also be divided as three intervals. During the first interval, two DC bulk capacitors C 1 and C 2 release the stored energy to the load and store the energy in C_Inductor windings L 2 and L 3 . During the second interval, the windings L 2 and L 3 resonate with the resonant capacitor Cr to transfer the stored magnetic energy from the windings L 2 and L 3 to the winding L 1 . During the third interval, the couple inductor's stored energy and the input power line will charge the resonant capacitor Cr through the couple inductor C_Inductor's winding L 1 .
[0058] Because the input power line always feeds energy to the converter. The problem of the input current during 60 degree dead-time near the line zero crossings can be solved. Because the currents in the branches of D 1 and D 2 are discontinues, it is possible to use a high frequency couple inductor couple and output a unipolar high frequency current source, that is, the instant current varies from a fixed value to zero. There are the currents of D 1 and D 2 only during 60 degree dead time, and the couple boost mode automatically works during that period to shape the input current. The circuit's circulating current is low. It is the winding L 1 's current that can be used to absorb the input energy from the power line as the instantaneous output voltage of the rectifier is lower than the one of C 1 or C 2 .
[0059] A second embodiment of the present invention is illustrated in FIG. 9. In this embodiment, a buck circuit 100 is provided as a following power stage, in which the buck circuit works in a continuous or discontinues current mode.
[0060] [0060]FIG. 10 illustrates a third embodiment of the present invention. In this embodiment, a discharge lamp, such as, for example, a high intensity discharge (HID) lamp is driven by the PFC converter. A full bridge inverter 200 outputs a low frequency square AC current source.
[0061] [0061]FIG. 11 illustrates a fourth embodiment of the present invention. In this embodiment, a half bridge 300 is employed (used) to drive the discharge lamp, such as, for example, a fluorescent lamp, with a high frequency sinusoidal AC current.
[0062] FIGS. 12 to 18 illustrate the fifth, sixth, seventh, eighth, ninth, tenth and eleventh embodiments of the present invention. In the fifth embodiment (FIG. 12), the PFC converter is interfaced to a discontinues current input buck-boost converter 400 . The sixth embodiment (FIG. 13) illustrates the PFC converter of the present invention being interfaced to a discontinues current input flyback converter 500 . The seventh embodiment (FIG. 14) illustrates the PFC converter of the present invention being interfaced to a discontinues current input forward converter 600 . The eighth embodiment (FIG. 15) illustrates the PFC converter of the present invention being interfaced to a two-switch forward converter 700 . The ninth embodiment (FIG. 16) illustrates the PFC converter of the present invention being interfaced to a two-switch flyback converter 800 . The tenth embodiment (FIG. 17) illustrates the PFC converter of the present invention being interfaced to a half-bridge DC-DC converter 900 . The eleventh embodiment (FIG. 18) illustrates the PFC converter of the present invention being interfaced to a full-bridge DC-DC converter 1000 .
[0063] FIGS. 19 to 28 illustrate the modified topologies shown in FIG. 9 to FIG. 18, that is, the low pass filters are shifted from AC side to DC side. As the low pass filters are shifted from AC side to DC side, the diode Df is inserted to make the current in L 1 unipolar. The benefit of low pass filter in DC side is that the rectifier can be low speed.
[0064] [0064]FIG. 31 illustrates the modified topology for the topology shown in FIG. 8. The operation concept is the same. The difference of two topologies is the multi-winding couple inductor C_Inductor. In FIG. 8, the couple inductor has three separated windings. In FIG. 31, the couple inductor has two separated windings but one winding has a tapping. For two windings couple inductor, the couple coefficiency can be higher and the manufacture cost can be lower. All circuits shown in FIG. 9 to FIG. 18 can use the circuit shown in FIG. 31 for power factor correction function.
[0065] [0065]FIG. 32 illustrates the modified topologies shown in FIG. 8, that is, the low pass filters are shifted from AC side to DC side. As the low pass filter is shifted from AC side to DC side, the diode Df is inserted to make the current in L 1 unipolar. All circuits shown in FIG. 19 to FIG. 28 can use the circuit shown in FIG. 32 for power factor correction function.
[0066] The present invention provides several significant improvements over prior art devices. The PFC converter of the present invention provides an improved PFC function, as compared to prior art. The present invention does not impose any additional current or voltage stresses on the switches. In addition, the improved valley-fill power stage of the instant invention is passive and fewer additional components. As a result, the efficiency and reliability of the PFC stage of the present invention is very high and the manufacture cost is low. | A switching power supply AC-DC-DC or AC-DC-AC with power factor corrector function is provided. The switching power supply circuit includes a quasi active shaping function that shapes an input current of a power line. In the whole system, the active switch or switches are only used to control the output power and no more current stress on the active switch or switches. It is possible to minimize the whole system size. | 8 |
CROSS-REFERENCE TO RELATED APPLICATION
This is a continuation of application Ser. No. 004,418 filed Jan. 18, 1979 now abandoned.
BACKGROUND OF THE INVENTION
Synthetic fibers and mixtures of synthetic and natural fibers are bound together with various latexes to produce non-woven fabrics as shown, for example, in U.S. Pat. Nos. 3,256,234; 3,720,562; 3,769,067; 3,784,401; 3,920,868; and 4,001,163. While styrene-butadiene latexes are very economical in this use, such latexes have, historically, failed to compete in this market largely because of poor stability to heat and light and, in some cases, insufficient wet tensile strength. Hitherto, it has been difficult to obtain non-woven fabrics having both desirable strength characteristics and a soft, cloth-like feel from synthetic fibers.
SUMMARY OF THE INVENTION
We have now found that non-woven fabrics having excellent wet strength, stability to heat and light and a desirable cloth-like feel may be prepared by impregnating synthetic fibers with a liquid binder system containing a polymer, the solids of which comprise from about 35 to 60 weight percent of a hard monomer, about 0 to 45 weight percent of butadiene or isoprene, about 10 to 50 weight percent of an acrylate ester having from 1 to 8 carbon atoms in the ester portion and about 1 to 5 weight percent of an ethylenically unsaturated mono- or dicarboxylic acid.
DETAILED DESCRIPTION OF THE INVENTION
The non-woven fabrics prepared by the method of this invention, in addition to having excellent wet strength and stability to heat and light, have a cloth-like feel and are admirably suited for use in products such as diapers and inner liners for various articles of clothing.
The hard monomer to be employed may be, for example, styrene, acrylonitrile or methyl methacrylate, with styrene being preferred. Advantageously, the hard monomer is employed in an amount of from 40 to 45 weight percent of the polymer solids. When acrylonitrile is employed as all or a portion of the hard monomer, the resulting products are advantageously employed in non-skin contact applications such as oil or air filters or as dimensional stabilizers in road construction.
The soft portion of the polymer solids advantageously comprises butadiene and butyl acrylate. Butadiene is preferably present in an amount of from about 20 to 40 weight percent, most advantageously, about 32 to 38 weight percent. The acrylate portion of the polymeric solids preferably amounts to about 15 to 35 weight percent of such solids, and most preferably comprises about 15 to 25 weight percent of such solids.
The unsaturated carboxylic acid is preferably employed in an amount of from 2 to 4 weight percent, solids basis. Below 2 weight percent, the dispersion is less stable. Above 4 weight percent, the product has reduced heat stability. While monocarboxylic acids such as acrylic and methacrylic acid may be employed, the preferred acids are dicarboxylic acids such as, for example, itaconic and fumaric acid.
The latexes employed in this invention may be prepared by known procedures for polymerization in aqueous emulsion. Typically, the monomers are dispersed in an aqueous solution of from about 0.05 to 5 percent of a polymerization catalyst, such as potassium persulfate, and from about 0.05 to 5 percent of a pH stable surface-active agent capable of emulsifying the monomers as known in the art. Polymerization is initiated by heating the emulsified mixture, usually between 60° and 100° C. and is continued by maintaining the polymerizing emulsion at the desired temperature. After the polymerization has reached the desired conversion of monomer to polymer, the latex is filtered to remove any precoagulum and may be stabilized to storage by the addition of a small amount of known antioxidant. A preferred method is that disclosed in U.S. Pat. No. 3,563,946. In the preparation of the polymer, chain transfer agents such as CCl 4 , bromoform and alkyl mercaptans are advantageously employed. The resulting polymer is a soft, tacky polymer having a glass transition temperature (Tg) of from about +10° C. to -40° C.
The latex is compoundable with known additives in the non-woven industry such as, for example, melamine-formaldehyde resins for improvement in water, detergent and solvent resistance, flame-retardant additives, anionic or nonionic surfactants, heat and light stabilizers and fillers.
The method of this invention may be employed with a wide variety of synthetic fibers such as, for example, polyester, polypropylene and nylon and mixtures of such fibers with natural fiber such as rayon and wood pulp. The procedural steps and apparatus commonly employed in the art may be employed in the method of this invention. Some of these procedures are set out in the prior art referred to in the Background of the Invention.
The invention is further illustrated by the following examples in which all parts are by weight unless otherwise indicated. In the examples, the non-woven webs were placed between two pieces of cotton gauze scrim and the scrim/fiber sandwich was immersed in the latex bath and immediately fed through a squeeze roll saturator. The polymer pickup was controlled by adjusting the percent solids of the latex and the pressure on the rollers.
EXAMPLE 1
A latex (about 50% solids) was prepared from the following recipe:
Styrene: 42.5 parts
Butadiene: 35.0 parts
Butyl Acrylate: 20.0 parts
Itaconic Acid: 2.50 parts
Carbon Tetrachloride: 5.0 parts
Anionic Surfactant: 1.0 part
Sodium Persulfate: 0.8 part
The latex was stabilized by the addition of:
Antioxidant: 2.0 parts
Diammonium Phosphate: 0.25 part
Chelating Agent: 0.50 part
NH 4 OH to pH: 8-8.5
The above latex was saturated on a polyester non-woven web (4×14") having a density of 1 1/2 ounces per square yard at 20% polymer pickup, air dried, then cured at 300° F. for 3 minutes. The properties in the cross machine direction of the resulting fabric were:
Dry Tensile: 5.2 lbs/in
% Elongation: 63
Wet Tensile: 3.4 lbs/in
Wet % Elongation: 58
% W/D Tensile: 65
This fabric had a soft, cloth-like feel and excellent stability to heat and light.
EXAMPLE 2
Following the above procedures, a latex (Ca 50% solids) was prepared from the following recipe and tested as before:
Styrene: 37.5 parts
Butadiene: 40.0 parts
Ethyl Acrylate: 20.0 parts
Itaconic Acid: 2.5 parts
Carbon Tetrachloride: 4.0 parts
Anionic Surfactant: 0.75 part
Sodium Persulfate: 0.8 part
The latex was stabilized by the addition of:
Antioxidant: 1.5 parts
Diammonium phosphate: 0.25 part
Chelating Agent: 0.50 part
NH 4 OH to pH: 8-8.5
The results of testing a non-woven polyester fabric prepared as in Example 1 were:
Dry Tensile: 5.5 lbs/in
% Elongation: 63
Wet Tensile: 2.8 lbs/in
Wet % Elongation: 57
% W/D Tensile: 51
This fabric had a soft, cloth-like feel and good stability to heat and light.
EXAMPLE 3
Following the above procedures, a latex (Ca 50% solids) was prepared from the following recipe and tested as before:
Styrene: 48.0 parts
Butadiene: 30.0 parts
2-Ethylhexyl Acrylate: 20.0 parts
Itaconic Acid: 2.0 parts
Carbon Tetrachloride: 10.0 parts
Anionic Surfactant: 0.75 part
Sodium Persulfate: 0.8 part
The latex was stabilized by the addition of:
Antioxidant: 1.5 parts
Diammonium Phosphate: 0.25 part
Chelating Agent: 0.50 part
NH 4 OH to pH: 8-8.5
The results of testing a non-woven polyester fabric prepared as in Example 1 (pickup 25%) were:
Dry Tensile: 6.3 lbs/in
% Elongation: 49
Wet Tensile: 4.7 lbs/in
% W/D Tensile: 75
This fabric had a soft, cloth-like feel and good stability to heat and light. | Non-woven fabrics are prepared from synthetic fibers by impregnating the fibers with a liquid binder system containing a polymer of from 35 to 60 weight percent of a hard monomer, 0 to 45 weight percent of butadiene or isoprene, 10 to 50 weight percent of an acrylate having from 1 to 8 carbon atoms in the ester portion and 1 to 5 weight percent of an ethylenically unsaturated mono- or dicarboxylic acid. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a method for optimizing the characteristics of a fluid circulation established in an annular space around a tubular element and notably a rotating tubular element such as a long pipe or a drillpipe string, by taking into account in a dynamic manner the deformations undergone by this tubular element and thus the variation of the annular space around it.
The method according to the invention is particularly suited for narrow annuli where the ratio of the diameter of the inner tubular element to the diameter of the outer conduit is greater than 0.5.
The method according to the invention is applied notably within the scope of petroleum drilling operations or in geotechnics, where it allows determination of the speed field of a drilling fluid circulating in the space around a drillpipe string and of the pressure losses resulting from frictions, for complex geometries of this space, due to the motions and deformations of the pipes.
The method is particularly well-suited for optimizing the conditions of circulation of the fluids during drilling operations performed in narrow wells according to the so-called slim hole technique where, on account of the reduced annular dimensions, pressures may be generated which jeopardize the stability of the formation which is crossed.
2. Description of the Prior Art
A number of publications give an account of theoretical or practical studies on the circulation of fluids in wells around a string of motionless or rotating pipes and the variations in the flow parameters due to the eccentricity of a string of pipes and its deformations, and notably in narrow wells.
The following documents may be cited for example: --Vaughn, R. D., 1965, "Axial Laminar Flow of non Newtonian Fluids in Narrow Eccentric Annuli", S.P.E., Vol.5, Dec., --Bourgoyne, A. T. et al, 1986, "Applied Drilling Engineering", in SPE Text Book Series, Vol.2, --Markatos N. C. G. et al, "Flow in an annulus of non-uniform gap"in Trans. IChemE, Vol.56, --Reed, T. D. et al, 1993, "A new model for Laminar, Transitional and Turbulent Flow in Drilling Fluids", in SPE 25456, Proceedings of the Prod. Operations Symposium, Oklahoma City, Okla., --Marken, C. D. et al, 1992, "The influence of drilling conditions on annular pressure losses", article SPE 24598, --Dodge D. W. and Metzner A. B., 1959, "Turbulent Flow of Non-Newtonian Systems", AIChE Journal, Vol.5, p.33.
The resolution method which is generally used for modelling the behaviour of a fluid circulating in an eccentric annulus is to represent the space around the pipe to a juxtaposition of slots. It was previously considered using this model that either the pipe was centered in the conduit, or any eccentricity was uniform all along this pipe. Within the scope of the length of the hypothesis, the slots are considered as being parallel and of constant thickness over the total length thereof.
The circulation of drilling fluids in a slim hole where a drillpipe string rotates is a complex phenomenon which is difficult to model. Among the important factors influencing pressure losses, for a given mud type and rate, are the rotating speed of the drillpipe string and the geometry of the annular space around and along the drillpipe string notably because of the eccentricity thereof in the hole, its motions, its flexions, etc.
In fact, the respective axes of the drilled hole and of the drillpipe string are most often offset with respect to one another on account of the deviations of one and/of the flexions of the other. The eccentricity of the annular space between them depends on this offset which varies along the drillpipe string.
Therefore in many cases, and notably for well drilling, the existing models, based on the assumption that the relative position of the pipe with respect to the conduit is uniform over its total length, do not model well the complexity of the phenomena. Besides, the existing models do not take into account the significant changes which are brought about due to the mud circulation by the coupling between the effects of the rotation of the pipe and its variable eccentricity with respect to the conduit or to the hole.
Existing models therefore do not enable the driller to predict safely the pressure losses and the real speed fields resulting from all these parameters: rotation of the pipe, effective rheological properties of the fluids used in practice, variable non-uniform eccentricity, etc, and thus to optimize the fluid circulation to be established: flow rate, rheology, considering the rotating speed.
SUMMARY OF THE INVENTION
The object of the method according to the invention is to build a representative model of the speed field of a fluid circulating in a conduit around a tubular pipe of variable eccentricity, for laminar as well as turbulent flow, and of the distribution of the annular pressure losses as a function of the flow rates.
The model allows optimization of the characteristics of a fluid circulation which is established in an annular space around a tubular element whose eccentricity is variable, such as a long pipe or a drillpipe string, subjected to deformations, notably when this annular space is relatively narrow.
The method according to the invention comprises modelling the flow of fluid circulation in the annular space by considering the shape thereof to be variable all along the tubular element and by taking into account the real rheological properties of the fluid (viscosity variation with the shear rate for example), so as to determine the value of the speed field and the value of the pressure at any point along this annular space.
The method can also comprise the application, to these values obtained for a tubular element of variable eccentricity, of a dimensionless correction factor dependent on the Reynolds number (Re) and on the Taylor's number (Ta) of the fluid used, so as to take account of the pressure loss variations in the annulus generated by the rotating speed of the tubular element.
When the respective ratios of the inertial and viscous effects, in the axial direction and the azimuthal direction respectively, are greater than a predetermined value, the dimensionless correction factor to be applied can be determined through the relation:
Rp=ARe.sup.c Ta.sup.d, where
A, c and d are parameters whose values can be selected within defined ranges.
According to an embodiment of the method, which can be used when the skewness of the tubular element is relatively low, the possible dynamic changes in the shape of the tubular element are taken into account by applying another correction factor, substantially constant and independent of the shape of the tubular element, ranging for example between the following interval:
0.1<R<10.
The method according to the invention takes into account the two essential factors which govern the evolution of the pressures in narrow annuli: the variable eccentricity and the rotation of the tubular element. It therefore allows the annulus pressure to be related in a reliable manner to the operating parameters: geometry, flow rate, rotating speed, and to the rheology of the circulating fluid.
The distribution of the pressure losses, which is determined by applying the method according to the invention, as it is defined above, in complex cases where any fluid circulates in a narrow annulus around a rotating pipe subjected to deformations, particularly when the annular space around the pipe is narrow, is in keeping with the practical results which have been measured.
Within the scope of drilling operations notably, application of the method thus allows defining the optimum fluid rheology to maintain a high flow rate enabling good cuttings removal to be obtained without the annulus pressures going beyond a safety range and damaging the hole. The method thus allows defining rules concerning the rheology and therefore the composition of the fluids, and notably fluids without solid particles used in slim holes.
BRIEF DESCRIPTION OF THE DRAWINGS
Other features and advantages of the method according to the invention will be clear from reading the description hereafter, with reference to the accompanying drawings in which:
FIGS. 1 and 2 diagrammatically show an elongated tubular element subjected to deformations of respectively sinusoidal and linear variation;
FIG. 3 diagrammatically shows in cross-section an eccentric tube in a conduit such as a well;
FIGS. 4 and 5 diagrammatically show a skew annulus respectively in a closed and in a spread position;
FIG. 6 diagrammatically shows the variation, as a function of the skewness of a tubular element, of a correction factor to be applied to the pressure losses obtained by assuming a zero or invariable eccentricity, predicted by the method of the invention and experimentally corroborated;
FIG. 7 diagrammatically shows the variation, as a function of the shear thinning index, of the same correction factor;
FIG. 8 shows how the shear stress varies with the shear rate, in the case of Newtonian fluids and of non-Newtonian fluids; and
FIG. 9 shows the distribution of speeds V and the pressure isovalues in an annulus whose configuration varies in a sinusoidal way along its axis.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In a well 1, the shape of the drillpipe string 2 driving the bit varies generally from one site to the other (FIGS. 1 to 3). It depends on the deviation of the drilled hole, on the tension or the compression exerted on the pipe, etc. The real configuration of a drillpipe string is defined by three geometric parameters:
the eccentricity, which is a dimensionless number whose value is 0 when the pipe and the conduit are concentric and 1 when the pipe touches the inner wall of the conduit, as defined by the relation: ##EQU1## R 0 and R i are respectively the radii of the conduit and of the pipe (FIG. 1), and is the distance between their respective axes;
the maximum eccentricity, which is less than 1 if the pipe is provided with centralizers (of radius R t ) which prevent it from touching the wall of the conduit; ##EQU2## the skewness S, which is the ratio of the average diameter of the annular space d avg =2r avg to the the interval between two successive inflections of the pipe L, ##EQU3##
For the calculations, according to a known model, the annular space 3 is likened to a series of juxtaposed slots of variable thickness according to the real eccentricity. The annular space 3 around the pipe is spread out (FIGS. 4, 5) and the fluid is assumed to flow between a certain number of plates of variable distance in the axial direction (FIG. 9).
It can be shown that, for 0≦x≦L and 0≦y≦2r avg , the expressions of the equations given in Cartesian co-ordinates the thickness of the slots for a skew annulus of sinusoidal (FIG. 1) or rectilinear variation (FIG. 2) are as follows: ##EQU4## with e max defined by (2) and r avg =0.5d avg .
The following dimensionless motion equation is used to model the flow of the fluid in a relatively thin annular space whose eccentricity is variable: ##EQU5##
with x.sub.D =x/.sub.Δ L, y.sub.D =y/πr.sub.avg, z.sub.D =z/(D.sub.o -D.sub.i)(D.sub.i 2R.sub.i and D.sub.o =2R.sub.o)
which relates the pressure P, the axial speed u, the azimuthal speed v, the viscosity , the co-ordinates X 0 (axial) and Y 0 (azimuthal), Z 0 the ratio S defined by (3), the friction coefficient f and the Reynolds number Re.
Two relations connecting the pressure and the averaged speed components in a radial direction are also used: ##EQU6##
The value of the dimensionless Viscosity D is 1 for Newtonian fluids. For non-Newtonian fluids, the velocity of flow and the transverse length scale are taken into account for calculating this dimensionless viscosity. P D =P/P 0 where P 0 , which represents the pressure losses of the fluid circulating in a concentric annulus similarly reduced to a slot, is calculated by the relations established by Reed et al in the publication cited above.
Numerical Model
The previous relations are applied to a numerical model of the finite difference type such as that defined by Markatos et al in the above-mentioned publication, where the annular space is divided into grids, each one representing a slot such as they are defined above, whose thickness is determined by solving Equations (4) or (5).
The Markatos model, which was applied to Newtonian fluids, is improved as described hereafter to take into account the whole of the rheological laws to which drilling fluids are subject.
For a given P, at the abscissa x=0, the model initially considers a linear variation profile of the pressure and an average speed field based on a given flow rate for each slot. The Reynolds number Re, the friction coefficient (f) and the viscosity are calculated.
For a Newtonian fluid of laminar flow for example, the product fRe is equal to 24 and the viscosity is independent of the shearing. In this case, Equations (6) to (8) are simplified.
The modelling method according to the invention allows the scope of the previous model to be extended to non-laminar flow regimes of any fluids whose shear thinning index n' is generally less than 1, which correspond better to the circulations to be modelled in practice.
For a non-Newtonian fluid, this relation has to be modified. The product fRe of the correction factor f by the Reynolds number Re must first be integrated into Equations (6) to (8), for any fluids. The viscosity of the fluids generally varies with the shear rate (FIG. 8). They comply with the rheological law:
τ=K'γ.sup.n' (9)
where τ is the shear stress and K' and n' are the parameters defined in the above-cited publication by Dodge D. W. et al.
In order to take into account this type of fluid, the definition of the Reynolds number Re is modified and the method described by Reed, T. D. et al in the above-cited publication is used, between this modified number Re and the friction coefficient f, for the resolution of the model.
The so-called GNM method described by Reed et al in the above-mentioned publication is used to assess the diffusion term z D 3 /fReηD in Equation (6). This diffusion term being known for each grid, the discrete form of Equation (6) is solved to obtain a new pressure field. A new speed field is calculated from the same Equations (7) to (8). The calculations are repeated until a convergence of the calculated speed fields is obtained. An example of a speed field obtained with a sinusoidal eccentricity is shown in FIG. 9.
In all the cases where the flow becomes turbulent in the wider parts of the annular space while remaining laminar in the narrow parts, because of a fast variation of the diffusion term from one grid to the other, a relaxation method known in the art is used. It allows stability to be increased, but it decreases the rate of convergence.
When convergence is obtained, the numerical integration of the axial speed field gives the flow rate.
Simple modifications of Equations (4) and (5) allow the model to be adapted to cases of zero or uniform eccentricity of the pipe.
Eccentricity Corrections
Estimation of the speed field and of the distribution of the pressure losses in a narrow annulus is very complex on account of the possible diversity of the skewness and of the eccentricity of the pipe under real working conditions.
However, the method according to the invention allows the speed field and the pressure loss distributions around a rotating pipe of great length to be modelled.
In the general case of a pipe whose skewness coefficient (1/S) is low, the distribution of the pressure losses is determined by integrating into the model defined by relations 6 to 8 the analytic expressions of the thickness variation of the slots corresponding to the real shape of the pipe, and for example Equations (4, 5) if the deformation of the pipe is of the sinusoidal or linear type. This leads to complex calculations.
The method according to the invention provides a much more simple solution in the case where the skewness of the pipe is low (higher 1/S factor).
A correction factor R is defined as the ratio, for the same flow rate, of the pressure losses per unit of length (P/L)e, generated by an eccentric pipe, to the corresponding pressure losses (P/L)c generated by the same centered pipe.
The curves of FIG. 6, determined by modelling in accordance with the method, show that the correction factor R varies in an asymptotic manner and remains practically invariable whatever the real shape (broken line or sinusoidal shape) of the pipe, when the skewness coefficient 1/S reaches rather high values (1/S>10), which corresponds to a low deformation of the pipe.
Fluid circulation laboratory tests have been carried out with an installation comprising a 24-mm inside diameter conduit and a 18-mm outside diameter inner pipe sinusoidally bent. In FIG. 6, point a of co-ordinates 1/S=12, R=0.66 and point b of co-ordinates 1/S=18, R=0.64 correspond respectively to values obtained during these tests. Comparing the model predictions and the experimental results shows that they agree in an excellent way.
Under normal conditions of use, the deformation of a pipe in a narrow conduit or slim hole, notably of a drillpipe string in an oil well, is generally not marked. This is the most common method of operation in practice. The pressure losses resulting from an eccentricity of the pipe (P/L)e can thus be calculated simply, substantially regardless of the skewness coefficient 1/S in the case of annuli of great length.
The calculation may generalize in the case of non-Newtonian fluids, whatever their shear thinning degree. The variation of the correction factor R which has to be introduced when the pipe is eccentric but slightly skewed (high 1/S value) as a function of the shear thinning index n is shown in FIG. 7 for a skewness of the linear or sinusoidal type.
Introducing this correction factor R thus permits easily to obtaining of, for low skewnesses, the results of an eccentric configuration from the results obtained in the case of a centered pipe, for any rheological law of the type given by relation (9).
Rotation Corrections
The values obtained by modelling must thereafter be modified to take into account the effects generated by the rotation of the pipe.
Tests concerned with the flow of a shear-thinning fluid around a pipe centered in a conduit have shown that the evolution of the pressure loss as a function of the rotating speed W depends on the flow regime generated by the coupling of the axial motion and of the tangential motion.
It is known that a tangential flow between two coaxial cylinders characterized by the magnitude of the Taylor's number defined by ##EQU7## where W is the rotating speed and n is the viscosity.
In the absence of any axial motion, the tangential flow is governed by the Taylor's number Ta. When Ta<41.3, the flow is laminar. For Taylor's numbers ranging between 41.3 and about 400, it is observed that stable vortexes referred to as Taylor's vortexes are superposed on the circular current lines. The flow becomes turbulent for Ta values>400.
It is also well-known that, when superposed on a tangential flow, an axial flow modifies the values of Ta corresponding to the limits of the transition zone. Similarly, a tangential flow superposed on an axial flow can affect the values of Re corresponding to a laminar-turbulent transition in the axial direction.
In order to bring out the overall trends of the effects of the rotation of the pipe and the value of the correction factors to be brought to the previous results, so as to take into account the flow type, it is useful to put the different parameters into a dimensionless form.
The Reynolds number defined by Dodge et al for a non-Newtonian fluid in the above-mentioned publication is thus used.
The Taylor's number characterizing the ratio of the inertial effects to the viscous effects in the azimuthal direction is given by relation (10) providing that its definition is extended so as to include the shear thinning effects. To that effect, the Newtonian viscosity has to be replaced in this relation by the viscosity of a power-law fluid, calculated at the value of the shear rate on the inner wall (against the pipe) corresponding to the rotating speed W.
The ratio Rp of the annulus pressure for a given rotating speed W to the annulus pressure for a zero rotation at the same flow rate is also defined by the relation: ##EQU8##
Another dimensionless parameter is constructed from the Taylor's and Reynolds numbers: ##EQU9## where U m is the velocity of flow. R w is a measurement of the ratio of the shear rates respectively in the azimuthal and in the axial direction.
The results obtained vary as a function of the values taken by the Reynolds and the Taylor's numbers:
1) Low Reynolds numbers (Re<200):
The ratio Rp decreases when the parameter Rw increases and it becomes significant when Rw becomes greater than 2. The pressure drop observed is related to the decrease in the fluid viscosity which is related to the superposition of the azimuthal shear on the axial shear. The pressure loss decrease which is observed for low values of the Reynolds number is the result of the viscosity loss brought by the tangential motion.
2) Low Taylor's numbers (Ta<200):
The pressure ratio Rp asymptotically tends to a limit R pl greater than 1 for values of the Taylor's number Ta<200.
3) Taylor's and Reynolds numbers greater than 200
For this variation range, an empirical relation has been established as follows:
Rp=ARe.sup.c Ta.sup.d (13)
where coefficients A, c, d range between the following values:
0<A<10
0<c<2
0<d<2
with typical values as follows: A=0.29, c=0.17 and d=0.067.
Application to the results of this second correction factor dependent on the rotating speed and on the type of flow thus allows the pressure losses along the pipe to be obtained. | The method according to the invention permits adapting for any fluid, a known model representative of the circulation of a fluid in an annular space around a motionless pipe, centered or eccentric uniformly over the total length thereof, to more complex cases which are encountered in practice and notably in drilling. The invention comprises the application, to the pressure loss values obtained with the known model, of a first correction factor accounting for the eccentricity variations which the pipe may undergo notably because of the variations in the axial load applied or of straightness defects of the conduit, and of a second correction factor representative of the effects due to the rotation of the pipe. The method identifies the prominent pressure loss variations which are observed in narrow annular spaces. The method can be applied to narrow hole petroleum drilling (of the slim hole type). | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a fine operation mode changeover device for a hydraulic excavator which is intended to enable performance of accurate operation by simply changing over the operation to a fine operation mode when fine control of operation of a working machine such as a hydraulic excavator is provisionally required, for example, in leveling of a ground surface and in position adjustment on a dump vessel, and easy cancellation of the fine operation mode of the hydraulic excavator for returning to normal operation, thereby improving operability and work efficiency of the machine.
2. Description of the Related Art
When temporary fine control of the operation is required in such work as ground leveling by a hydraulic excavator or position adjustment on a dump vessel, such fine operation can be carried out with a far smaller quantity of fuel than in typical excavating work. Therefore, an engine revolution rate at a specified torque T 0 is controlled to N 1 , N 2 or N 3 (rev/min) and a required quantity of fuel, that is, V.N 1 , V.N 2 or V.N 3 (cc/min), while maintaining a capacity V (cc/rev) of a hydraulic pump to be driven by the engine at a fixed level, is controlled by reducing a fuel injection quantity as shown in an engine torque graph in FIG. 8, thereby reducing fuel consumption of the engine. As is well known, an absorption torque T of the hydraulic pump is denoted as T=kP×V wherein k is a proportional constant and P is a load pressure. If the capacity V (cc/rev) of the hydraulic pump is fixed, the load pressure P 0 of the hydraulic pump, having the absorption torque T 0 illustrated in FIG. 8, is proportional to the absorption torque T 0 . An oil quantity of a hydraulic pump is reduced by a method which reduces the capacity V of the hydraulic pump by fixing a fuel injection to the engine as shown in FIG. 9 (the rotation rate of the engine is approximately fixed) and changing over the operation of the working machine to the fine operation mode. However, in the case of a method for reducing the oil quantity of the hydraulic pump by decreasing the rotation rate of the engine from the engine rotation note N 1 , in a state where the capacity V of the hydraulic pump is kept fixed as shown in FIG. 8, the matching points A2, A3 for the lower engine rotation rates N 2 , N 3 , respectively, with the absorption torque T 0 corresponding to a specified load are further away from the center of the equivalent fuel consumption efficiency curve FC of the engine (hereinafter referred to as the equivalent fuel consumption curve with 100% at the center) than the matching point A 1 for the initial engine rotation N 1 , and therefore this method is disadvantageous in that the fuel consumption of the engine lowers accordingly and the operator will suffer from a great deal of fatigue in frequently repeated operations for adjusting the rotation rate of the engine during the work by the hydraulic excavator. In the method as shown in FIG. 9, assuming that k is a proportional constant and P is a load pressure, the absorption torque T of the pump is denoted as T=kP×V as described above, and therefore, when the maximum torque is required, reduction of the value V with respect to the maximum load pressure P set by the relief valve will result in reduction of absorption torque of the hydraulic pump from T S to T 1 . Accordingly, this method is also disadvantageous in that the matching point with the hydraulic pump is shifted from A S to A 1 , which is further away from the center of the equivalent fuel consumption curve FC of the engine. Therefore, the fuel consumption efficiency of the engine deteriorates due to the location of the matching point A 1 being further from the center of the equivalent fuel consumption curve FC than is the location of the matching point A S . The operating valves should be controlled in a small range where the operating strokes of operating valves are small, and the operability is deteriorated since only an insufficient capacity of the hydraulic pump can be obtained from the reduced absorption torque T 1 of the hydraulic pump because the load sensing control is not effected. As shown in FIG. 8, frequent changeover operations of the fine operation mode and the ordinary operation mode will bring about a considerable degree of fatigue to the operator.
SUMMARY OF THE INVENTION
A fine operation mode changeover device for a hydraulic excavator in accordance with the present invention comprises a variable capacity type hydraulic pump, an actuator to be driven by the above described hydraulic pump, an operating valve provided in a conduit between the hydraulic pump and the actuator, a load sensing control unit for the hydraulic pump, a fine operation mode changeover switch, and a controller which receives a changeover signal from the fine operation mode changeover switch and outputs a differential pressure signal of upper and lower streams of the operating valve, wherein a load sensing differential pressure signal from the controller is not outputted to the load sensing control unit since the fine operation mode changeover switch is not operated when the actuator of the hydraulic excavator is driven in a routine operation mode and the differential pressure between the upper stream and the lower stream of the operating valve is controlled to be a fixed differential pressure preset in the load sensing control unit. When a changeover signal from the fine operation mode changeover switch is entered into the controller to drive the actuator of the hydraulic excavator in the fine operation mode, the load sensing differential pressure signal from the controller is outputted to the load sensing control unit so as to reduce the capacity of the hydraulic pump through the capacity control cylinder.
The device in accordance with the present invention also comprises a variable capacity type hydraulic pump, an engine for driving the hydraulic pump, an actuator to be driven by the hydraulic pump, an operating valve provided in a conduit between the hydraulic pump and the actuator, a load sensing control unit, a fine operation mode changeover switch, and a controller which receives a changeover signal from the fine operation mode changeover switch and outputs a fuel injection quantity signal to a governor drive unit and a differential pressure signal of upper and lower streams of the operating valve, wherein a load sensing differential pressure signal from the controller is not outputted to the load sensing control unit since the fine operation mode changeover switch is not operated when the actuator of the hydraulic excavator is driven in a routine operation mode and the differential pressure between the upper stream and the lower stream of the operating valve is controlled to be a fixed high differential pressure preset in the load sensing control unit and simultaneously the horsepower of the engine rises up to a preset high horsepower. Accordingly, the capacity of the variable capacity type hydraulic pump increases and the rotation rate of the engine in reference to the specified torque is increased owing to the rise of the horsepower, and therefore the discharge per unit time of the variable capacity type hydraulic pump increases. When the fine operation mode changeover switch is operated to drive the hydraulic excavator in the fine operation mode, a low fuel injection quantity signal from the controller is outputted to the governor drive unit of the engine to reduce the horsepower of the engine and the differential pressure signal which seems to reduce the differential pressure between the upper and lower streams of the operating valve for the actuator is outputted to the load sensing control valve, and therefore the capacity of the variable capacity type hydraulic pump in reference to the specified amount of operation of the operating valve for the actuator reduces. Accordingly, the capacity of the variable capacity type hydraulic pump decreases and the rotation rate of the engine in reference to the specified torque is decreased owing to the reduction of the horsepower, and therefore the discharge per unit time of the variable capacity type hydraulic pump decreases.
The load sensing control unit is adapted to decrease the capacity of the hydraulic pump through the capacity control cylinder of the hydraulic pump according to the increase of the differential pressure signal to be outputted from the controller and to increase the capacity of the hydraulic pump through the capacity control cylinder of the hydraulic pump according to the decrease of the differential pressure signal. The load sensing control unit decreases the capacity of the hydraulic pump through the capacity control cylinder of the hydraulic pump when the differential signal outputted from the controller increases, and increases the capacity of the hydraulic pump through the capacity control cylinder of the hydraulic pump when the differential signal decreases.
The controller is adapted to output a low engine fuel setting signal from the engine fuel setter to the engine fuel signal generator by actuating the engine fuel setter and the load sensing differential pressure setter according to the changeover signal from the fine operation mode changeover switch and a low load sensing differential pressure setting signal from the load sensing differential pressure setter to the load sensing differential pressure signal generator to output a low fuel injection quantity signal from the engine fuel signal generator to the governor drive unit and a low load sensing differential pressure signal to the load sensing control unit and, when the controller receives the changeover signal from the fine operation mode changeover switch, the engine fuel setting device and the load sensing differential pressure setting device are actuated with the changeover signal. When the above described setting devices are actuated, the low engine fuel setting signal is outputted to the engine fuel signal generator and the low load sensing differential pressure setting signal is outputted to the low sensing differential pressure signal generator to output a low fuel injection quantity signal from the engine fuel signal generator to the governor drive unit of the engine and a low load sensing differential pressure signal from the load sensing differential pressure signal generator to the load sensing control unit.
The fine operation mode changeover switch is adapted to be provided on the operation lever of the operating valve. Since the fine operation mode changeover switch is provided on the operation lever of the operating valve, the fine operation mode or the normal operation mode can be easily selected by pushing or releasing the fine operation mode changeover switch even during operation of the working machine.
The device in accordance with the present invention further comprises a variable capacity type hydraulic pump, an actuator to be driven by the hydraulic pump, an operating valve provided in a conduit which connects the hydraulic pump and the actuator, a capacity control cylinder of the hydraulic pump, a fine operation mode changeover switch, a load sensing control unit which changes over the operation to decrease the capacity of the hydraulic pump through the capacity control cylinder owing to an increase of the difference of pilot pressures of the upper and lower streams of the operating valve, and a controller which outputs a specified electrical signal which serves to reduce the capacity of the hydraulic pump through the capacity control cylinder when a changeover signal from the fine operation mode changeover switch is entered, wherein the load sensing control unit, which uses a differential pressure of the upper and lower streams of the operating valve as a pilot pressure, is controlled so that the differential pressure of the upper and lower streams of the operating valve may be maintained at a fixed level through the capacity control cylinder according to the differential pressure of the pilot pressure when the operating valve is operated by the operation lever for driving the actuator of the hydraulic excavator in a standard operation mode. When the changeover signal is entered from the fine operation mode changeover switch into the controller to drive the actuator of the hydraulic excavator in the fine operation mode, a specified electrical signal which reduces the capacity of the hydraulic pump is outputted from the controller to the load sensing control unit through the capacity control cylinder.
Since the specified electrical signal to be outputted from the controller is adapted to be entered into a solenoid of a load sensing valve and reduce the capacity of the hydraulic pump through the capacity control cylinder, the specified electrical signal to be outputted from the controller is entered into the solenoid of the load sensing control unit and serves to reduce the capacity of the hydraulic pump. The device in accordance with the present invention comprises a variable capacity type hydraulic pump, an engine for driving the hydraulic pump, an actuator to be driven by the hydraulic pump, an operating valve provided in a conduit which connects the hydraulic pump and the actuator, a load sensing control unit of the hydraulic pump, a capacity sensor of the hydraulic pump, a rotation rate sensor of the engine, a hydraulic pressure sensor of the actuator, and a fine operation mode changeover switch, and further comprises a controller which receives the signals of the capacity sensor, the rotation rate sensor of the engine and the hydraulic pressure sensor of the actuator, calculates a control signal according to which the engine is driven with the minimum fuel consumption at the specified horsepower designated by the fine operation mode changeover switch and outputs this control signal to the load sensing control unit and the governor drive unit of the engine, wherein the capacity of the variable capacity type hydraulic pump can be reduced for the same operation amount of the operation lever by calculating the control signal according to which the engine is driven with the minimum fuel consumption at the specified horsepower for the fine operation mode stored in the controller, changing over the load sensing control unit according to the control signal and reducing the capacity of the hydraulic pump through the capacity control cylinder when the changeover signal from the fine operation mode changeover switch is entered into the controller to drive the actuator of the hydraulic excavator in the fine operation mode, and the engine can be operated with the minimum fuel consumption for the horsepower reduced by outputting the control signal to the governor drive unit of the engine.
The control signal with which the engine is operated with the minimum fuel consumption is set according to an engine torque and an engine rotation rate which provide the minimum fuel consumption on the equivalent horsepower curve of the engine and therefore the engine is operated with the engine torque and the engine rotation rate which provide the minimum fuel consumption on the equivalent horsepower curve.
The fine operation mode changeover switch is provided on the operation lever of the actuator to permit easy changing over of the fine operation mode and the standard operation mode by pushing and releasing the fine operation mode changeover switch even during operation of the working machine.
Thus the following effects can be obtained from the present invention. (1) A plurality of operation modes is available by changing over the operation mode. In any operation mode, a required flow rate can be ensured and the engine can be operated with the minimum fuel consumption since the rotation rate of the engine can be set independently of the adjustment of the capacity of the hydraulic pump by adjusting the capacity of the hydraulic pump according to the load sensing control. (2) The operability by the operator can be improved by load sensing control of the capacity of the hydraulic pump so as to operate the operating valve in a wide range. (3) A mode suited for the work can be selected by a simple operation, such as a mere touching of the fine operation mode changeover switch provided on the operation lever, to perform highly accurate operation of the working machine, and the work efficiency can be improved by operating the actuator at a high speed since the operation is immediately changed over to the normal operation mode when the fine operation mode changeover switch is released.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagram showing a control circuit according to the first embodiment of the present invention;
FIG. 2 is a diagram showing a control circuit according to the second embodiment of the present invention;
FIG. 3 is a diagram showing the details of the controller shown in FIG. 2;
FIG. 4 is a diagram showing a control circuit according to the third embodiment of the present invention;
FIG. 5 is a diagram showing the details of the controller shown in FIG. 4;
FIG. 6 is a diagram showing equivalent fuel consumption and equivalent horsepower curves on the torque T versus rotation rate N plane of the engine common to the second and third embodiments of the present invention;
FIG. 7 is a diagram showing equivalent absorption torque curves on the hydraulic pressure P versus capacity V plane of the hydraulic pump common to the first and third embodiments of the present invention;
FIG. 8 is a diagram showing the engine torque curves when the fuel injection quantity is varied in the prior art; and
FIG. 9 is a diagram showing the engine torque curve when the capacity of the hydraulic pump is varied while the fuel injection quantity is kept constant in the prior art.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
In FIG. 1 showing a first embodiment of the present invention, 1 is an engine, 2 is a hydraulic pump to be driven by the engine 1, 3 is an actuator of a working machine, 4 is an operating valve provided in conduits 5a, 5b which connect the hydraulic pump 2 and the actuator 3 of the working machine, 6 is a pilot operating valve for operating the operating valve 4, 6a is an operation lever of the pilot operating valve 6, 7 is a capacity control cylinder for driving a diagonal plate 2a of the hydraulic pump 2, 7a is a spring provided in a bottom chamber 7b of the capacity control cylinder 7 to energize a piston 7d in a direction toward a rod chamber 7c, 7e is a piston rod for coupling the piston 7d to the diagonal plate 2a, 8 is a load sensing control unit for changing over the control pressure of the capacity control cylinder 7, 8a is a solenoid of a load sensing valve 8 connected to a controller 15, 8b is a pilot cylinder of the load sensing valve 8 connected to an upper stream conduit 5a of the operating valve 4, 8c is a pilot cylinder of the load sensing control unit 8 connected to a lower stream conduit 5b of the operating valve 4, 8d is a differential pressure setting spring of a load sensing valve 8, 9 is a control pump as a control pressure source of the capacity control cylinder 7, 10 is a power source, 11 is a fine operation mode changeover switch, 11a is a return spring of the fine operation mode changeover switch 11, 12 is a magnet, 13 is a spring, 14 is a changeover switch, and 15 is a controller which enters a changeover signal from the changeover switch 14 and outputs a differential pressure signal ip of upper and lower streams of the operating valve 4 to the solenoid 8a of the load sensing control unit 8. The controller 15 comprises a load sensing differential pressure setter 16 and a load sensing differential pressure signal generator 17. 23 is a tank.
An operation of a configuration shown in FIG. 1 is described below. In an operation of the hydraulic excavator in a normal operation mode, the voltage of the power supply 10 is not applied to the magnet 12 since the fine operation mode changeover switch 11 is not pressed, and therefore the magnet 12 is demagnetized and the changeover switch 14 is connected with the contact A by the spring 13. Accordingly, the voltage of the power supply 10 is not applied to the load sensing differential pressure setter 16 in the controller 15, and therefore the load sensing differential pressure signal i p is not outputted from the load sensing differential pressure signal generator 17 to the solenoid 8a of the load sensing control unit 8. Accordingly, the load sensing control unit 8 operates to provide a high load sensing differential pressure which is determined by a preset spring 8d. As described above, since the operation in a normal operation mode is carried out with a high rotation rate of the engine and a high capacity of the hydraulic pump, the discharge of the hydraulic pump per unit time increases and the actuators can be operated at high speeds to improve the working efficiency. For changing over the operation to the fine operation mode during the normal operation mode, the voltage of the power supply 10 is applied to the magnet 12 and the changeover switch 14 is connected to the contact B when the fine operation mode changeover switch 11 is pressed. The voltage of the power supply 10 is applied to the load sensing differential pressure setter 16 in the controller 15 and, when a low load sensing differential pressure setting signal ΔP b is outputted from the load sensing differential pressure setter 16 to the load sensing differential pressure signal generator 17, the load sensing differential pressure signal generator 17, which serves as a decreasing function generator, outputs the load sensing differential pressure signal i p corresponding to the low load sensing differential pressure setting signal ΔP b to the solenoid 8a of the load sensing control unit 8, and therefore the capacity of the hydraulic pump 2 is reduced for the same operation amount of the operating valve 4. Since the discharge of the hydraulic pump 2 per unit time decreases as described above even though the rotation of the engine is constant, fine operation will be easy. In this first embodiment, the device is simplified in its construction and the operating valve can be controlled in a wide range of operation, and it is therefore advantageous in that the operability can be improved and the changeover of the modes is easy. However, the measures for reducing fuel consumption of the engine have not been taken.
In FIGS. 2 and 3 showing a second embodiment of the present invention, the descriptions of the configurations and operations of 1-14, 16, 17 and 23 in FIG. 2 are omitted because of being the same as in FIG. 1. 20 is a controller which comprises the load sensing differential pressure setter 16, the load sensing differential pressure signal generator 17, the engine fuel setter 18 and the engine fuel signal generator 19, receives the changeover signal from the fine operation mode changeover switch 11, outputs the differential pressure signal i p of upper and lower streams of the operating valve 4 to the solenoid 8a of the load sensing control unit 8 and outputs the fuel injection quantity signal i h to the governor drive unit 1a of the engine 1.
The following describes the operation of the configuration shown in FIGS. 2 and 3. In FIG. 2, the fine operation mode changeover switch 11 is not pressed in the operation of the hydraulic excavator in the normal operation mode, and the voltage of the power supply 10 is not applied to the magnet 12; therefore the magnet 12 is demagnetized and the changeover switch 14 is forced to connect to the contact A by the spring 13. Accordingly, the voltage of the power supply 10 is not applied to the load sensing differential pressure setter 16 in the controller 20, and therefore the load sensing differential pressure signal i p from the sensing differential pressure signal generator 17 is not outputted to the solenoid 8a of the load sensing control unit 8 and the fuel injection quantity signal i h from the engine fuel signal generator 19 is not outputted to the governor drive unit 1a of the engine 1. Accordingly, the load sensing control valve 8 provides a high load sensing differential pressure which is determined by the preset spring 8d, and the governor drive unit 1a of the engine 1 is operated with a preset high fuel injection quantity. As described above, since the operation in a normal operation mode is carried out with a high rotation rate of the engine and a high capacity of the hydraulic pump, the discharge of the hydraulic pump per unit time increases and the actuators can be operated at high speeds to improve the working efficiency. For changing over the operation to the fine operation mode during the normal operation mode, the voltage of the power supply 10 is applied to the magnet 12 and the changeover switch 14 is connected to the contact B when the fine operation mode changeover switch 11 is pressed. The voltage of the power supply 10 is applied to the load sensing differential pressure setter 16 in the controller 20 and, when a low load sensing differential pressure setting signal ΔP b is outputted from the load sensing differential pressure setter 16 to the load sensing differential pressure signal generator 17, the load sensing differential pressure signal generator 17, which serves as a decreasing function generator, outputs the load sensing differential pressure signal i p corresponding to the low load sensing differential pressure setting signal ΔP b to the solenoid 8a of the load sensing control unit 8, and therefore the capacity of the hydraulic pump 2 is reduced for the same operation amount of the operating valve 4. Since the voltage of the power supply 10 is applied to the engine fuel setter 18 in the controller 20, when a low engine fuel setting signal H b from the engine fuel setter 18 is outputted to the engine fuel signal generator 19, the engine fuel signal generator 19, which serves as an increasing function generator, outputs a low engine fuel signal i h corresponding to the low engine fuel setting signal H b to the governor drive unit 1a of the engine 1 and the rotation rate of the engine is reduced. As described above, the operation is carried out with a low rotation rate of the engine and a low capacity of the hydraulic pump in the fine operation mode and therefore the discharge of the hydraulic pump 2 per unit time decreases and fine operation can be easily carried out.
In FIGS. 4 and 5 showing a third embodiment of the present invention, the descriptions of the configuration and operations of 1-14 and 23 in FIG. 4 are omitted because of being the same as in FIG. 1. 21 is a hydraulic sensor for converting a hydraulic pressure of a lower stream conduit 5b of the operating valve 4 to an electrical signal, 31 is a pump capacity sensor for detecting the capacity of the hydraulic pump 2, 32 is an engine rotation rate sensor for detecting a rotation rate of the engine 1, and 30 is a controller which receives the detection signals and the command signals from the hydraulic sensor 21 of the actuator 3, the operation mode changeover switch 11, the pump capacity sensor 31 of the hydraulic pump 2 and the engine rotation rate sensor 32 of the engine 1, calculates the control signals i N and i V according to which the engine 1 is operated with the minimum fuel consumption and the specified horsepower assigned by the operation mode changeover switch 11 and outputs the control signal i N to the governor drive unit 1a of the engine 1 and the control signal i V to the solenoid 8a of the load sensing valve 8. This controller 30 includes a target value setter 22 for setting a target engine rotation rate N S and a target engine torque T S for the standard operation mode, a capacity difference calculator 24 for calculating a difference ΔV S between the target capacity V S calculated from the target engine torque T S and a detection value P of the hydraulic sensor 21 and a detection value V of the capacity sensor 31, and an engine rotation rate difference calculator 25 for calculating a difference ΔN S between the target engine rotation rate N S and an actual engine rotation rate N detected by the engine rotation rate sensor 32. Similarly for the fine operation mode, the controller 30 includes a target value setter 33 for setting a target engine rotation rate N B and a target engine torque T B for the fine operation mode, a capacity difference calculator 26 for calculating a difference ΔV B between the target capacity V B calculated from the target engine torque T B and a detection value P of the hydraulic sensor 21 and a detection value V of the capacity sensor 31, and an engine rotation rate difference calculator 27 for calculating a difference ΔN B between the target engine rotation rate N B and an actual engine rotation rate N detected by the engine rotation rate sensor 32. In addition, the controller 30 includes a control signal generator 28 for converting the capacity difference signal ΔV S or ΔV B to a control signal i V to be applied to the solenoid 8a, and a control signal generator 29 for converting the engine rotation rate difference signal ΔN S or ΔN S to a control signal i N to be applied to the governor drive unit 1a.
An operation of a configuration shown in FIGS. 4 and 5 is described below. For operation of the hydraulic excavator in the standard operation mode, the changeover switch 14 is connected to the contact A unless the fine operation mode changeover switch 11 is pressed, and the target engine rotation rate N S and the target engine torque T S and the detection value P of the hydraulic sensor are entered into the capacity difference calculator 24 by the target value setter 22 in the controller 30. As is well known, assuming that k is a proportional constant, the target engine torque T S can be denoted as T S =kPV S , and therefore the target pump capacity V S is calculated and the difference ΔV S between the target pump capacity V S and the detection value V of the pump capacity sensor 31 is calculated. When the signal of the capacity difference ΔV S is outputted to the control signal generator 28, the control signal i V corresponding to the capacity difference signal ΔV S as shown is outputted to the solenoid 8a of the load sensing valve 8. If the capacity difference signal ΔV S is small in the control signal generator 28, the control signal i V is set to have a large value. For example, if the actual pump capacity V to be detected by the pump capacity sensor 31 is excessively large for the target pump capacity V S , the capacity difference signal ΔV S becomes small and the control signal i V becomes large, and therefore the energizing force of the solenoid 8a which pushes the load sensing valve 8 rightwardly becomes large. Accordingly, the control pressure of the control pump 9 is supplied to the bottom chamber 7b of the capacity control cylinder 7, and a piston rod 7e of the capacity control cylinder 7 moves to the right side to control the diagonal plate 2a of the variable capacity type hydraulic pump 2 in a direction where the capacity is decreased. Thus the capacity is controlled so that the capacity difference signal ΔV S is 0, that is, the actual pump capacity V becomes the target pump capacity V S . Similarly, when the target engine rotation rate N S set by the target value setter 22 and the actual engine rotation rate N detected from the engine rotation rate sensor 32 are entered into the engine rotation rate difference calculator 25, a difference ΔN S between the target engine rotation rate N S and the actual engine rotation rate N detected by the engine rotation rate sensor 32 is calculated. If the engine rotation rate difference signal ΔN S is small in the control signal generator 29, the control signal i N is set to have also a small value. For example, if the actual engine rotation rate N detected by the engine rotation rate sensor 32 is excessively small for the target engine rotation rate N S , the value of each of the engine rotation rate difference signal ΔN S and the control signal i N becomes large. Therefore, the capacity is controlled so that the governor drive unit moves to a larger stroke to cause more fuel to be injected and the engine rotation rate N to increase. The engine rotation rate difference signal ΔN.sub. S becomes 0, that is, the actual engine rotation rate N becomes the target engine rotation rate N S . Thus, excavation work can be carried out at the target engine rotation rate N S and the target engine torque T S with which the minimum fuel consumption can be achieved. For operation of the hydraulic excavator in the fine operation mode, the changeover switch 14 is connected to the contact B when the fine operation mode changeover switch 11 is pressed and the target engine rotation rate N B and the target engine torque T B are set by the target setter 33 in the controller 30, and the excavation work in the fine operation mode can be carried out, as in the standard operation mode, with the target engine rotation rate N B and the target engine torque T B with which the minimum fuel consumption can be achieved. For changing over the operation to the standard operation mode during the fine operation mode, the fine operation mode changeover switch 11 which is kept depressed should be released. Then the changeover switch 14 is changed over to the contact A and the machine can be immediately released from the fine operation mode and changed over to the standard operation mode.
FIG. 6 shows an equivalent horsepower curve and an equivalent fuel consumption curve which are drawn on the torque T versus the engine rotation rate N plane where FC denotes the equivalent fuel consumption curve with the fuel consumption of 100% at the center thereof. HP S denotes the equivalent horsepower curve in the standard operation mode, HP B denotes the equivalent horsepower curve in the fine operation mode, and T S and T B respectively denote the engine torque on equivalent horsepower curves HP S and HP B where the minimum fuel consumption is achieved.
FIG. 7 is a diagram showing an equivalent torque curve drawn on the hydraulic pressure P versus the capacity V plane of the hydraulic pump to be driven by the above described engine wherein T S and T B are respectively absorption torques of the hydraulic pump corresponding to the engine torques T S and T B shown in FIG. 6.
INDUSTRIAL APPLICABILITY
The present invention is to provide a useful fine operation changeover device for a hydraulic excavator, capable of conducting accurate work, for example, ground leveling or position adjustment on a dump vessel, while simply changing over a working machine such as a hydraulic excavator to the fine operation mode which is temporarily required, and improving operability and work efficiency by easily canceling the fine operation mode in the standard operation mode. | A hydraulic excavator adapted to be changed over simply to a fine operation mode so as to control the capacity of a hydraulic pump through load-sensing control to thereby make it possible to perform accurate work when the machine needs to be finely operated temporarily for operations such as ground levelling, and position adjustment on a dump vessel, wherein the fine operation mode is easily cleared to switch the excavator to a standard mode to thereby improve operability, as well as work efficiency. When the excavator is switched to the fine operation mode so as to control the capacity of the hydraulic pump through load-sensing control for accurate work, the engine is driven at such a torque and engine revolution as permitting a minimum fuel consumption, thus reducing the fuel consumption of the engine. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This is a Continuation of application Ser. No. 12/947,448 filed Nov. 16, 2010, which claims priority under 35 U.S.C. §119 from Korean Patent Application No. 10-2010-0000445, filed on Jan. 5, 2010 in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference in its entirety.
BACKGROUND
1. Field of the Invention
Apparatuses and methods consistent with exemplary embodiments relate to providing contents, and more particularly, to providing contents for devices connected to communicate with one another.
2. Description of the Related Art
Prices of electronic devices have been decreasing, but consumer's purchasing power has been increasing. Thus, it has become common for one user to own a number of electronic devices.
Moreover, with the development of digital and networking technologies, one network has been generated by bundling a number of electronic devices. The electronic devices forming the network are mutually operated and generate many new functions which were not possible on an individual basis.
Accordingly, it is necessary to find ways for a user to connect their electronic devices and to enjoy more diverse and convenient functions.
SUMMARY
Exemplary embodiments address at least the above problems and/or disadvantages and other disadvantages not described above. Also, exemplary embodiments are not required to overcome the disadvantages described above, and an exemplary embodiment may not overcome any of the problems described above.
The present invention provides a method for converting a sink device, which suspends a content transmission to the sink device, transmits the content to another sink device, thus converting a sink device to output the contents, and an apparatus for providing the content using the same.
According to an exemplary embodiment, a sink device conversion method of a plurality of sink devices which output a content transmitted from a source device includes: receiving a sink device conversion command from a first sink device; transmitting the content to a second sink device, if a sink device conversion approval is received from the second sink device; and transmitting a control authority related to a content provision from the first sink device to the second sink device.
The sink device conversion method may further include suspending the transmission of the content to the first sink device after the receiving operation.
The transmitting may include transmitting the content after the moment when the transmission was suspended in the suspension operation.
The sink device conversion method may further include transmitting a turn-off request to the first sink device after the suspension operation.
The sink device conversion method may further include transmitting a turn-on request to the second sink device after the receiving operation.
The sink device conversion command may be a command which makes the source device convert from the first sink device to the second sink device and transmit the content to the second sink device.
The source device is a content-play device which plays contents including at least one of a video signal and an audio signal, and the plurality of sink devices comprise a video device and an audio device. The transmitting of the content comprises separating the contents into a video signal and an audio signal; transmitting the video signal into the video device; and transmitting the audio signal into the audio device.
According to another exemplary embodiment, a content-providing apparatus which converts a sink device outputting a content includes: a communication interface which enables communication between the content-providing apparatus and at least a first sink device and a first sink device; and a control unit which receives a sink device conversion command from the first sink device through the communication interface, transmits the content to the second sink device through the communication interface if a sink device conversion approval is received from the second sink device through the communication interface, and transfers a control authority related to a content provision from the first sink device to the second sink device.
The control unit may suspend content transmission to the first sink device if the sink device conversion command is received from the first sink device.
The control unit may transmit the content to the second sink device through the communication interface after the moment when the transmission was suspended.
The control unit may transmit a turn-off request to the first sink device through the communication interface after suspending the content transmission to the first sink device.
The control unit transmits a turn-on request to the second sink device though the communication interface if the sink device conversion command is received from the first sink device.
The sink device conversion command is a command which makes the content-providing apparatus convert from the first sink device to the second sink device and transmit the content to the second sink device.
The content includes at least one of a video signal and an audio signal, the second sink device includes a video device and an audio device, and the control unit transmits the video signal separated from the content to the video device through the communication interface and transmits the audio signal to the audio device through the communication interface.
According to another exemplary embodiment, a method for converting from one sink device to another sink device includes: transmitting data to the sink device; receiving from the sink device a conversion request; and transmitting data to the other sink device based on the conversion request.
The method may further include suspending the transmission of data to the sink device after the conversion request is received. Also, the method may further include receiving a conversion approval from the other sink device after the conversion request is received.
The method may further include transferring a control authority from one sink device to another sink device.
According to yet another exemplary embodiment, a source apparatus for converting a destination sink device to another destination sink device, includes: a communication interface which transmits content to the destination sink device and receives from the sink device a conversion request; and a control unit which receives and processes the conversion request. The communication interface may transmit the content to the other sink device based on the conversion request.
The control unit may suspend the transmission of data to the sink device after the conversion request is received.
According to an aspect of an exemplary embodiment, a control authority may be transferred from the sink device to the other sink device.
According to another aspect of an exemplary embodiment, the source apparatus may receive a conversion approval from the other device after the conversion request is received.
According to still another exemplary embodiment, a method for converting from a first sink device to another sink device, includes: transmitting data to the sink device; receiving from the sink device a conversion request to transmit data to a second sink device; receiving from a third sink device a conversion approval; and transmitting the data to the third sink device. The method may further include transferring a control authority from the sink device to the third sink device.
According to still another exemplary embodiment, a source apparatus for converting a destination sink device to another destination sink device, includes: a communication interface which transmits data to the destination sink device and receives, from the destination sink device, a conversion request to transmit data to a second destination sink device; and a control unit which receives and processes the conversion request, wherein the communication interface transmits the data to a third destination sink device after receiving a conversion approval from the third destination sink device.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and/or other aspects will be more apparent by describing certain exemplary embodiments with reference to the accompanying drawings, in which:
FIG. 1 is a drawing of a home network to which exemplary embodiments are applicable;
FIG. 2 is a detailed block diagram of a Blu-ray Disk Player (BDP) illustrated in FIG. 1 ;
FIG. 3 is a flow chart provided to explain a sink device conversion method according to an exemplary embodiment;
FIG. 4 is a flow chart provided to explain a sink device conversion method according to another exemplary embodiment; and
FIG. 5 is a drawing of another home network to which exemplary embodiments are applicable.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
Certain exemplary embodiments will now be described in greater detail with reference to the accompanying drawings.
In the following description, the same drawing reference numerals are used for the same elements even in different drawings. The matters defined in the description, such as detailed construction and elements, are provided to assist in a comprehensive understanding of exemplary embodiments. Thus, it is apparent that exemplary embodiments can be carried out without those specifically defined matters. Also, well-known functions or constructions are not described in detail since they would obscure the exemplary embodiments with unnecessary detail.
1. Home Network to which the Present Invention is Applicable
FIG. 1 illustrates a home network to which exemplary embodiments are applicable. The home network in FIG. 1 comprises 1) a Blu-ray Disk Player (BDP) 100 and a DTV-1 210 located in a Room-1 10 , 2) a DTV-2 220 located in a Room-2 20 , and 3) a DTV-3 230 located in a Room-3 30 .
The BDP 100 is a kind of source device which provides contents recorded in a Blu-ray (BD). The DTVs 210 , 220 , 230 are kinds of sink devices which output contents provided by the BDP 100 working as a source device and provide the contents for a user.
The DTVs 210 , 220 , 230 are connected to the BDP 100 to communicate with each other. Accordingly, contents and a control command/request can be transmittable between the DTVs 210 , 220 , 230 and the BDP 100 .
In detail, the BDP 100 can send contents generated by playing a BD to the DTVs 210 , 220 230 . Moreover, the BDP 100 can generate a command/request to control the DTVs 210 , 220 , 230 and send it to the DTVs 210 , 220 , 230 . Moreover, a control command on the BDP 100 can be input into the DTVs 210 , 220 , 230 by a user and can be sent to the BDP 100 .
2. BDP Detailed Configuration
FIG. 2 is a detailed block diagram of the BDP 100 illustrated in FIG. 1 . As illustrated in FIG. 2 , the BDP 100 comprises a BD playing unit 110 , an audio/video (AV) processing unit 120 , a communication interface 130 , a control unit 140 , and a user-input unit 150 .
The BD playing unit 110 reads content data recorded on the BD and sends it to the AV processing unit 120 .
The AV processing unit 120 performs necessary signal processing on the content data sent from the BD playing unit 110 . In detail, the AV processing unit 120 decompresses the content data sent from the BD playing unit 110 . Moreover, the AV processing unit 120 can also separate the decompressed content into a video signal and an audio signal.
The communication interface 130 is connected to the previously-mentioned DTVs 210 , 220 , 230 to communicate with each other. A content control command/request is exchanged between the BDP 100 and the DTVs 210 , 220 , 230 through the communication interface 130 .
The control unit 140 controls the functions of the BDP 100 in general based on 1) a control command input from the user-input unit 150 , or 2) a control command received from the DTVs 210 , 220 , 230 through the communication interface unit 130 .
The control command ‘1)’ refers to a control command directly input by a user into the BDP 100 unit to control the BDP unit 100 . The control command ‘2)’ refers to a control command indirectly input by a user through the DTVs 210 , 220 , 230 , to control the BDP unit 100 .
Particularly, the control unit 140 controls the BDP 100 and the DTVs 210 , 220 , 230 to ensure that one DTV, which is a sink device where the contents read by the BD playing unit 110 and signal processed by the AV processing unit 120 are output, can be changed to a different DTV where contents can be output.
In detail, the control unit 140 controls a sink device which outputs contents, wherein the sink device can be changed, or converted among the DTVs 210 , 220 , 230 .
3. Sink Device Conversion Process #1
Sink device conversion is performed based on the command of a user. A process where the control unit 140 controls a sink device conversion, if a user commands a sink device to be converted from the DTV-1 210 to the DTV-2 220 , will be explained in detail with reference to FIG. 3 .
FIG. 3 is a flow chart provided to explain a sink device conversion method according to an exemplary embodiment. A sink device conversion command is input by a user through the sink device DTV-1 210 where contents are being output, and is sent to the BDP 100 .
As illustrated in FIG. 3 , if a sink device conversion command (from the DTV-1 to the DTV-2) is received from DTV-1 ( 210 ) (S 320 —Y) while contents are being transmitted to the DTV-1 210 (S 310 ), the control unit 140 suspends the ongoing content transmission which has been going on in operation S 310 . (S 330 )
In operation S 330 , content playing/transmission is suspended automatically in the BDP 100 , and outputting is suspended automatically in the DTV-1 210 .
To resume the content playing/transmitting and outputting, the user needs to move from Room-1 to Room-2 and input a sink device conversion approval into the DTV-2 220 . The DTV-2 220 sends the sink device conversion approval input by the user, to the BDP 100 .
When the sink device conversion approval is received from the DTV-2 220 (S 340 —Y), the control unit 140 controls the BD playing unit 110 and the AV processing unit 120 to resume the playing of contents. The control unit 140 controls the communication interface unit 130 to transmit the played contents to the DTV-2 220 (S 350 .)
If a sink device conversion approval is received from the DTV-2 220 (S 340 —Y), it means that the user is ready to watch the contents through the DTV-2 220 .
Content transmission in operation S 350 takes place after the moment when the transmission is suspended in operation S 330 ; i.e., to enable a user to watch the contents seamlessly.
Since then, the control unit 140 transfers a BDP control authority from the DTV-1 210 to DTV-2 220 (S 360 .) The DTV, which has the control authority, is a DTV where a user command on the BDP unit 100 such as commands to play, pause, fast forward and rewind a content in the BDP 100 are input.
The control authority is transferred from the DTV-1 210 to DTV-2 220 . Therefore, a user can input a command about the BDP unit 100 through the DTV-2 220 , not through the DTV-1 210 . Accordingly, the BDP unit 100 receives a command related to the performance of its functions from the DTV-2 220 , not from the DTV-1 210 .
4. Sink Device Conversion Process #2
Thus far, a case has been described where a user inputs a sink device conversion approval into the DTV which is commanded to be converted into a sink device. In other words, the case has been described that, 1) after a user commands to convert a sink device from the DTV-1 210 to the DTV-2 220 , 2) a user inputs a sink device conversion approval into the DTV-2 220 after moving to the Room-2.
However, a case can occur where a user inputs a sink device conversion approval into another DTV, not the DTV which is commanded by a user to convert a sink device, because of ignorance or misunderstanding of the user. For example, 1) a user commands to covert a sink device from the DTV-1 210 to the DTV-2 220 , 2) but the user misidentifies the DTV-3 230 located in the Room-3 as the DTV-2 220 , thus moving to the Room-3 and inputting a sink device conversion approval into the DTV-3 230 .
In this case, the control unit 140 receives a sink device conversion approval from the DTV-3 230 , not from the DTV-2 220 . In such a case, a process of sink device conversion approval will be explained below in detail.
Detailed explanation on operation S 410 or operation S 430 in FIG. 4 can be inferred from the explanation on operation S 310 or S 330 illustrated in FIG. 3 , and is omitted.
A sink device conversion approval is received from the DTV-3 230 , not from the DTV-2 220 , the control unit 140 transmits a request for confirmation on, whether to convert a sink device to the DTV-3 230 not to the DTV-2 220 , to the DTV-3 230 (S 450 ).
The DTV-3 330 , which receives the conversion confirm request transmitted in operation S 450 , displays a text message on a display to ask whether to ‘convert a sink device to the DTV-3 230 , not to the DTV-2 220 .’ The DTV-3 330 receives a response from a user about the message and sends it in response to the confirm request from the BDP 100 .
If a “positive” confirm response is received from the DTV-3 230 (S 460 —Y), the control unit 140 controls the BD playing unit 110 and the AV processing unit 120 to resume the playing of contents, and controls the communication interface unit 130 to send the played contents to the DTV-3 230 (S 470 ).
If a confirm response is received from the DTV-3 230 , a user confirms that a sink device has been converted to the DTV-3 230 , not to the DTV-2 220 . Thus, the contents are transmitted to the DTV-3 230 in operation S 470 .
Afterwards, the control unit 140 transfers a control authority on the BDP 100 from the DTV-1 210 to the DTV-3 230 (S 480 ). Accordingly, the BDP 100 receives a command related to its functions from the DTV-3 230 , not from the DTV-1 210 .
If a “negative” confirm response is received from the DTV-3 230 (S 460 —N), the control unit 140 performs operation S 340 in FIG. 3 . Accordingly, if a sink device conversion approval is received from the DTV-2 220 (S 340 —Y), the control unit 140 performs operations S 350 and S 360 .
5. Automatic Power Management
After operation S 330 in FIG. 3 and operation S 430 in FIG. 4 , the control unit 140 can transmit a ‘power turn-off’ command to the DTV-1 310 . That is to automatically turn off the power of the DTV-1 310 where contents will not be output, because the content output is suspended now.
After operation S 330 in FIG. 3 or operation S 430 in FIG. 4 , the control unit 140 can transmit a ‘power turn-on’ command to the DTV-2 320 . That is to automatically turn on the power of the DTV-1 310 where the contents will be output.
6. Providing Contents Separately
In the above examples, contents are output through one DTV. However, that is just an example. Accordingly, it is possible to realize that the contents can be transmitted to more than two sink devices and be output. For example, the contents, which were output from the DTV-1 210 , can be transmitted to both of DTV-2 220 and DTV-3 230 and be output.
Moreover, a video signal and a audio signal contained in the contents can be transmitted to respective sink devices and be output. For example, as illustrated in FIG. 5 , under the home network, the BDP 100 can separate the contents into a video signal and an audio signal, 1) send the video signal to the DTV- 220 , and 2) the audio signal to a HTS (Home Theater System) 240 . In this case, a user can watch a video through the DTV-2 220 in the Room-2, and listen to an audio through the HTS 240 .
7. Variations
(1) Network
The home networks in FIG. 1 and FIG. 5 are examples of networks to which exemplary embodiments are applicable. Exemplary embodiments are not limited to the illustrated home network and can also be applicable to a different network from the illustrated one.
The devices mentioned in the home network assumed can be connected by a physical connection, but that is just an example for a better explanation. They can also be connected in a wireless manner.
(2) Source Device, Sink Device
The BDP mentioned in the above examples is a kind of source device and can be replaced with other kinds of devices other than the BDP. DTV and HTS are kinds of sink devices, therefore they can also be replaced with other kinds of devices.
As explained thus far, according to exemplary embodiments, a user can suspend the contents being transmitted to a sink device, transmit the contents to another sink device which the user wants, and change the sink device that outputs the contents. Accordingly, the user can convert the sink device to be provided with the contents, freely, so that the user enjoys more convenience.
The foregoing exemplary embodiments and advantages are merely exemplary and are not to be construed as limiting the present invention. The present teaching can be readily applied to other types of apparatuses. Also, the description of the exemplary embodiments is intended to be illustrative, and not to limit the scope of the claims, and many alternatives, modifications, and variations will be apparent to those skilled in the art. | A method for converting a sink device and an apparatus for providing a content using the same are provided. The method for converting the sink device includes receiving a sink device conversion command from a first sink device, transmitting the content to a second sink device if a conversion approval of the sink device is received from the second sink device, and transmitting a control authority related to a content provision from the first sink device to the second sink device. | 6 |
CROSS REFERENCE TO RELATED APPLICATION
None, however, Applicant filed Disclosure Document Number 320,514 on Nov. 9, 1992 which document concerns this application; therefore, by separate paper it is respectfully requested that the document be retained and acknowledgment thereof made by the Examiner. (MoPEP 1706)
BACKGROUND OF THE INVENTION
(1) Field of the Invention
This invention relates to fluid flow measurement and more particularly to the mounting of orifice plates in fluid pipe lines.
(2) Description of the Related Art
The measurement of the flow of fluids by orifices in the pipe lines is old and well known. Tens of thousands of fittings for such have been sold and are in commercial use.
Typically, a fitting for such use includes a structure having an inside diameter equal to and co-axial with a pipe line inside diameter. The fitting will have a seat slot therein by which an orifice plate mounted within a seal ring may be inserted. The ring seal will have an inside annular surface. The orifice plate will fit within a recess in the inside annular surface.
The accuracy of the measurement will be effected by the precision by which the orifice is mounted within the fitting. For example, KENDRICK, U.S. Pat. No. 5,085,250, describes the effect that lack of concentricity of the orifice within the orifice plate to the inside diameter of the fitting will have. KELLETT, U.S. Pat. No. 1,958,854 recognizes the desirability of having a uniform inside diameter along and adjacent to the orifice plate itself.
Recent changes have been made by the API 14.3 specifications of orifice seal ring protrusion and recess tolerances. I.e., the variations in the protrusions or recesses can affect the accuracy of the flow determination within the pipe line.
SUMMARY OF THE INVENTION
(1) Progressive Contribution to the Art
The invention disclosed in this application addresses the problem of variations of seal ring protrusions or recesses by providing adaptor rings so that the recesses and protrusions are minimized if not entirely eliminated.
Basically, the adaptor rings fit on either side of the orifice plate. The adaptor rings are of thin metal and have an inside diameter which is equal to the inside diameter of the fitting. The adaptor rings are held in place by radial flanges which are inserted within the same recess within the ring seal by which the orifice plate is inserted. I.e., it is known to the art, for example, KENDRICK, the orifice plate is inserted within a recess within the seal ring. Inasmuch as the seal rings as well as the orifices are normally made to precise dimensions, it is desirable to have notches cut in the sides of the recess to accommodate for the thickness of the radial flanges of the adaptor rings.
(2) Objects of this Invention
An object of this invention is to accurately measure the flow of fluids through a pipe line.
Another object of this invention is to provide adaptors and modified ring seals so that most of the orifice plate fittings and mountings may be converted to a more accurate device.
Further objects are to achieve the above with devices that are sturdy, compact, durable, lightweight, simple, safe, efficient, versatile, ecologically compatible, energy conserving, and reliable, yet inexpensive and easy to manufacture, install, and maintain.
Other objects are to achieve the above with a method that is rapid, versatile, ecologically compatible, energy conserving, efficient, and inexpensive, and does not require highly skilled people to install, and maintain.
Further objects are to achieve the above with a product that is easy to store, has a long storage life, is safe, versatile, efficient, stable and reliable, yet is inexpensive and easy to manufacture, install and maintain.
The specific nature of the invention, as well as other objects, uses, and advantages thereof, will clearly appear from the following description and from the accompanying drawings, the different views of which are not necessarily scale drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an axial sectional view of an orifice plate mounting according to this invention.
FIG. 2 is a perspective view partially cut away to show the mounting.
FIG. 3 is an axial sectional view of a portion of the mounting to a greatly enlarged scale.
FIG. 4 is an exploded view of a portion of FIG. 3 showing only the ring seal and slot.
FIG. 5 is a cross-sectional detail of the adaptor rings.
As an aid to correlating the terms of the claims to the exemplary drawing(s), the following catalog of elements and steps is provided:
W width, relaxed
D depth
F arrow
SW slot width
RW ring width
RH radial height
10 pipe line
12 pipe line inside diameter
14 fitting
16 fitting inside diameter
18 seat slot
20 ring seal
22 orifice plate
24 ring seal inside annular surface
26 ring seal recess
28 orifice
30 first upstream end (fitting)
32 second downstream end (fitting)
34 first upstream surface (slot)
36 second downstream surface (slot)
38 first upstream face (plate)
40 second downstream face (plate)
42 adaptor upstream ring
44 adaptor downstream ring
46 cylindrical circumferential flange
48 inside diameter
50 distal end
52 radial flange
54 radial face
56 outer diameter
58 upstream notch
60 downstream notch
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring more particularly to the drawing, there may be seen pipe line 10 which has pipe line inside diameter 12. It will be understood that the pipe line is shown at the inlet of fitting 14 only. However, it will be understood that the pipe line would continue from the flange but it is not shown for conciseness and clarity of the description. The fitting has an inside diameter 16 which is equal to the pipe line inside diameter. The fitting includes seat slot 18 which has slot width "SW" (FIG. 4). Ring seal 20 is within the seat slot 18. Orifice plate 22 is within the ring seal 20. The ring seal has annular inside surface 24 which is cylindrical. Ring seal recess 26 extends into the ring seal from the surface 24. The recess 26 has a certain depth "D" (FIG. 4). The ring seal also has a certain relaxed width "W". Relaxed width means the width of the ring seal when it is not compressed as when it is within the seat slot 18.
To orient the different elements it will be understood that there is a certain flow as shown by the arrow "F" through the pipe line 10, fitting 12, and orifice 28, within orifice plate 22. Therefore the fitting 14 has first end or upstream end 30 as well as second end or downstream end 32. Likewise the seat slot 18 has first surface or upstream stream surface 34 as well as second surface or downstream surface 36. The orifice plate has first or upstream face 38 as well as second or downstream face 40.
Those with skill in the art will understand that this detailed description, to this point, describes elements in combination that are old and well known to the art before this invention. As discussed above, the accuracy of the measurement of the flow "F" depends upon having a smooth and uniform cylindrical surface of the inside of the pipe line and fitting adjacent to the orifice plate 22. With the elastomeric seals 20, this was difficult to achieve because the seals would either protrude into the bore of the fitting, or there would be a recess within the walls of the fitting immediately adjacent to the orifice plate.
This invention provides a remedy for this problem by the provision of two adaptor rings 42 and 44. As may be seen in the drawing adaptor ring 42 would be a first or upstream ring. Adaptor ring 44 would be a second or downstream ring. However, it will be understood that these two are identical and that it is only their orientation with respect to the orifice plate 22 that makes them distinct. It may also be seen that the adaptor rings have two legs forming an L-shape cross section (FIG. 5).
Since the two adaptor rings 42 and 44 are identical, the detailed description describes either ring 42 or 44. The adaptor ring has cylindrical circumferential flange 46 and radial flange 52 in the form of legs of the L-shaped cross section. The circumferential flange 46 has inside diameter 48 which is equal to the inside diameter of the fitting and pipe line. The circumferential flange 46 has distal end 50. Radial flange 52 has radial face 54 which is opposite to the distal end 50. The adaptor rings has ring width "RW" which is the distance from the face 54 to the distal end 50. Radial height "RH" is the distance from the inside diameter of the adaptor ring to outer diameter 56 of the radial flange 52.
The ring seal 20 of this invention is modified by the provision of upstream notch 58 and downstream notch 60 within the ring seal recess 26. These two notches are identical and width of the notches is about equal to the thickness of the radial flange 52. The extent of each notch from the inside annular surface 24 is about one half the depth "D" of the recess 26.
In use, the orifice plate 22 is placed within the recess 26. The upstream adaptor ring 42 is placed with the radial face 54 against the upstream face 38 of the orifice plate. The radial flange 52 of the upstream adaptor ring will be inserted into the upstream notch 58. The downstream adaptor ring 44 will be placed with the radial face 54 against the downstream face 40 of the orifice plate. Also, the radial flange 52 will be inserted into the downstream notch 60.
As stated previously, the relaxed width "W" of the ring seal 20 will be slightly greater than the slot width "SW" of the slot 18.
Therefore when the ring seal 20 is inserted into the seat slot 18 it will be compressed slightly. However, the dimensions are such that the distance from the distal end 50 of the upstream ring to the distal end 50 of the downstream ring will be slightly less than the slot width "SW". However, because of the construction of the seal ring the adaptor ring will be maintained close or in contact with the orifice plate face. There will be a small or slight recess between the fitting and the adaptor plate but this will be negligible particularly with respect to the accuracy of the flow determination.
The embodiment shown and described above is only exemplary. I do not claim to have invented all the parts, elements or steps described. Various modifications can be made in the construction, material, arrangement, and operation, and still be within the scope of my invention.
The restrictive description and drawings of the specific examples above do not point out what an infringement of this patent would be, but are to enable one skilled in the art to make and use the invention. The limits of the invention and the bounds of the patent protection are measured by and defined in the following claims. | Thin metal adaptor rings fit over the elastomeric seal rings holding an orifice plate within a fitting. The thin metal rings have an inside diameter equal to the inside diameter of the pipe line and fitting. Therefore, the inside diameter is maintained without variations as previously resulted from protrusion or recess tolerances of the elastomeric seal rings. The seal ring is modified with notches to hold the thin metal adaptor rings in the desired position. | 5 |
FIELD OF THE INVENTION AND RELATED ART
This invention relates to a projection exposure apparatus and, more particularly, to a projection exposure apparatus called a "stepper" having a projection lens system by which a circuit pattern of a reticle or otherwise is projected upon a wafer.
The degree of integration of devices such as semiconductor microcircuits which are to be manufactured by use of exposure apparatuses has been rapidly increased. For example, at present, one-megabit memory devices can be manufactured practicably. Also, it is expected that four-megabit memory devices will be practicably manufactured in the near future. To meet such high-degree integration, exposure apparatuses for use in the manufacture of microcircuits should have high performance. As an example, the apparatus should have superior alignment capability for precisely superimposing different patterns in plural pattern printing processes. Also, it should have a superior processing capability that allows execution of the wafer printing procedure with high throughput. Further, the apparatus should have excellent resolution that permits printing of fine patterns having a linewidth not greater than 0.8 micron.
While various types of exposure apparatuses have been developed, step-and-repeat type projection exposure apparatuses called "steppers" are prevalently used. The projection exposure apparatus includes a projection lens system having been corrected, precisely, for various optical aberrations in order to assure improved pattern transfer or printing performance. However, it is not difficult to completely avoid the optical aberrations, particularly the chromatic aberration.
For diminishing the effect of the chromatic aberration, it is a very effective means to narrow the bandwidth of the wavelength of the light used for the pattern printing. U.S. patent application Ser. No. 813,226 assigned to the same assignee of the subject application has proposed use of a multilayered interference thin film filter for narrowing the wavelength range of the light used for the printing.
The currently available steppers prevalently use, as for the photoprinting light, g-line rays having a wavelength (central wavelength) 436 nm. The light of g-line has a bandwidth which is, as shown in FIG. 2, 10 nm (half width) at the peak 436 nm. Recently, however, when the light of g-line is used for the photoprinting, its bandwidth is narrowed in some cases by a suitable means to an order of 5 nm (half width) such as shown in FIG. 3. The bandwidth narrowing is made to diminish the effect of the chromatic aberration of the projection optical system, thereby to assure high resolution performance.
However, the bandwidth narrowing is not always advantageous. Namely, for the light having the same peak intensity (see FIG. 4), the band narrowing results in cutting or intercepting such quantity of light as corresponding to the hatched area in FIG. 4. This innevitably causes substantial reduction in the quantity of light that can be used for the photoprinting. This leads to a problem that, in a case where a pattern having a relatively wide line-width is going to be photoprinted in some of various printing procedures for the manufacture of the same microcircuit, the printing of such relatively wide line-width pattern has to be executed with an insufficient quantity of light.
SUMMARY OF THE INVENTION
It is accordingly a primary object of the present invention to provide a projection exposure apparatus which constantly ensures optimum projection exposure suited to the characteristics of a pattern, to be photoprinted, such as the linewidth, for example.
In accordance with one aspect of the present invention, to achieve the above object, there is provided a projection exposure apparatus which includes a projection lens system for projecting a pattern of an original upon a workpiece, an illumination optical system for illuminating the original with a light having a predetermined central wavelength, and a bandwidth changing arrangement effective to change the bandwidth of the light irradiating the original.
In accordance with one preferred form of the present invention which will be described later, an illumination optical system of a projection exposure apparatus has a plurality of optical elements having different bandpass characteristics. These optical elements are selectively and retractively inserted into a path of the light from a light source such as an Hg lamp or otherwise.
Namely, the optical elements are interchangeably used in the illumination optical system so as to change the bandwidth of the light used for the photoprinting. This allows that, for the printing of such a pattern having a relatively wide linewidth, the printing is carried out with a large quantity of light having a relatively broad bandwidth. Thus, high throughput is ensured. On the other hand, for the printing of such a pattern having a narrow linewidth, light having a very narrow bandwidth is used to thereby minimize the effect of the chromatic aberration of the projection lens system. Thus, high-resolution printing is attainable. In this manner, the wafer processing capability and the resolution characteristics of the exposure apparatus are made adjustable as desired.
These and other objects, features and advantages of the present invention will become more apparent upon a consideration of the following description of the preferred embodiments of the present invention taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic and diagrammatic view of a projection exposure apparatus according to one embodiment of the present invention.
FIGS. 2 and 3 are graphs, respectively, showing the spectral characteristics of a g-line light having a half width 10 nm and a g-line light having a half width 5 nm.
FIG. 4 is a graph schematically showing the difference in the quantity, for the light shown in FIG. 2 and the light shown in FIG. 3.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring first to FIG. 1, there is shown a projection exposure apparatus according to one embodiment of the present invention, which apparatus includes an illumination optical system and a control system.
Denoted at 1 in FIG. 1 is a photomask having a circuit pattern formed thereon. Denoted generally at 3 is an illumination optical system which includes at least two different bandpass filters and a filter changing arrangement. Also, denoted generally at 2 is a control system for controlling the changing of the filters.
Light emitted from an Hg lamp 31 included in the illumination optical system 3 is corrected by a parabolic mirror 32 and then is deflected by a reflection mirror 33. The light from the mirror 33 passes through a sharp-cut filter 34 which is effective to cut the wavelengths in the "heat wave" region. Subsequently, the light passes through a bandpass filter 35, whereby the bandwidth of the light to be used for the photoprinting is determined. After passing the filter 35, the light is directed by a condenser lens and a reflection mirror to the photomask 1 (which may of course be a reticle), thereby to irradiate the same as the "photoprinting light".
Denoted at 40 in FIG. 1 is a projection lens system which comprises a plurality of lens elements. The projection lens system 40 has been corrected for the various optical aberrations, with reference to a particular design wavelength (central wavelength) which is that of the g-line light in this embodiment. The projection lens system has an imaging magnification in a range of 1/5 to 1/10.
Denoted at 41 is a wafer having a surface which is coated with a suitable resist material. The wafer 41 is placed on a wafer stage 42 which is movable in suitable directions.
The circuit pattern of the photomask 1 as illuminated by the light from the illumination optical system 3 is projected by the projection lens system 40 upon the wafer 41 in a reduced scale. By this, the circuit pattern of the photomask 1 is transferred onto or photoprinted on the wafer 41.
The light emitted from the lamp 31 contains plural line spectrums such as g-line, h-line (405 nm), e-line (546 nm) and otherwise. In the projection exposure apparatus of the present embodiment, the sharp-cut filter 34 and the bandpass filter 35 (or 36) are used for the wavelength selection, such that light of a single line spectrum having a central wavelength corresponding to that of the g-line, is extracted. Further, the extracted g-line light has a bandwidth which is determined by the bandpass characteristics of the bandpass filter 35 or 36. In the present embodiment, the bandpass filters 35 and 36 have been designed so that the light passed through the bandpass filter 35 (hereinafter such light will be referred to also as a "first photoprinting light") has the spectral characteristics such as shown in FIG. 2 while, on the other hand, the light passed through the bandpass filter 36 (hereinafter such light will be referred to also as a "second photoprinting light") has the spectral characteristics such as shown in FIG. 3.
Each of the bandpass filters 35 and 36 may be provided by a multi-layered interference thin film filter such as disclosed in the aforementioned U.S. patent application Ser. No. 813,226 or it may be formed by a wavelength selecting element such as an etalon or otherwise.
In the projection exposure apparatus of the present embodiment, the bandpass filter 35 is used for the photoprinting of such a pattern having a relatively wide linewidth. On the other hand, the bandpass filter 36 is used for the photoprinting of such a pattern having a narrow linewidth. Accordingly, for the photoprinting of a pattern having a relatively large linewidth (e.g. 1.5-2.0 microns), the throughput of the exposure apparatus can be increased (e.g. 1.5-2 times higher). On the other hand, for the photoprinting of a pattern having a small linewidth (e.g. 0.7-0.8 micron), the effect of the chromatic aberration of the projection lens system 41 can be minimized sufficiently. It will be understood that the bandpass filters 35 and 36 are interchanged in accordance with the photomask 1 used (namely, the linewidth of the circuit pattern).
The bandpass filters 35 and 36 are fixedly mounted to a common support member which is coupled to a rotational shaft of an actuator 37. By rotating the support member, the bandpass filters 35 and 36 are interchanged.
Description will now be made of the sequence for changing the bandwidth of the photoprinting light having a particular central wavelength.
First, for the selection of a suitable bandwidth in accordance with the kind or type of a photomask 1 to be used, an operator designates, by typing an input keyboard 21 of the control system 2, a particular bandwidth to be selected or a particular filter having bandpass characteristics corresponding to the bandwidth to be selected. The information concerning the bandwidth to be used is stored into a memory 22 by way of a console CPU (central processing unit) 24. At the same time, such information is displayed on a CRT (cathode ray tube) 23. Subsequently, the information concerning the bandwidth stored in the memory 22 is transmitted to a control CPU 25, wherein the information signal is converted into an instruction voltage corresponding to the selected bandwidth. The instruction voltage is applied to a driving circuit 26, such that the actuator 37 is driven to replace a bandpass filter (e.g. 35) positioned in the path of the light from the lap 31 by another bandpass filter (e.g. 36). The actuator 37 may comprise a DC motor, a pulse motor, an air cylinder or otherwise.
Position detecting sensor 38 is provided to detect the position of the extracted bandpass filter (which is the filter 35 in this case) and, therefore, the position of the newly introduced bandpass filter (which is the filter 36 in this example). When the selected bandpass filter is placed at a correct position and if this is confirmed by the sensor 38, the bandwidth changing operation is completed.
In the manner described above, the bandpass filters 35 and 36 provided in the illumination optical system can be selected as desired.
In the present embodiment, as has hitherto been described, the bandpass filters 35 and 36 are selected as desired to thereby change the bandwidth of the photoprinting light having a central wavelength equal to that of the g-line. However, the bandwidth changing (i.g. changing the wavelength range) is attainable also by controlling a continuous spectrum which exists about the line spectrum such as the g-line. In such case, the bandpass filters 35 and 36 may be designed and manufactured so that the bandpass filter 35 is effective to extract a particular line spectrum together with a continuous spectrum adjacent to the particular line spectrum while the bandpass filter 36 is effective to cut the continuous spectrum with the result that only the particular line spectrum is extracted. Details of the relation between the line spectrum and the continuous spectrum are disclosed in the aforementioned U.S. patent application Ser. No. 813,226.
Each of the bandpass filters 35 and 36, when it is introduced, is preferably disposed at such position at which the light from the light source such as the lamp 31 advances as a parallel light (i.e. the position at which the chief ray advances in parallel to the optical axis of the illumination optical system). With this arrangement, the wavelength selecting characteristics of the filter can function correctly, for the light from the light source.
While in the present embodiment two bandpass filters are used as the wavelength variably-selecting optical means which is effective to change the bandwidth, such optical means may comprise a combination of a sharp-cut filter and an interference filter (such as an etalon or otherwise) or a bandpass filter formed by a multilayered interference thin film. In a case where the wavelength selecting optical means is provided by a combination of a sharp-cut filter and an interference filter or two or more bandpass filters, the bandwidth may of course be changed by changing one or more filters or by changing the combination of these filters.
The present invention is effectively applicable also to a projection exposure apparatus having a laser such as an excimer laser as the light source. Namely, the bandwidth (wavelength range) of the laser beam can be variably narrowed, as desired, by interchanging different wavelength selecting elements such as etalons, diffraction gratings or otherwise having different band-narrowing characteristics.
In accordance with the present invention, as has hitherto been described, the printing of a pattern having a relatively large linewidth can be executed with a large quantity of light, thus ensuring high throughput. On the other hand, for the printing of a pattern having a minute line width, the effect of the chromatic aberration of a projection lens system can be minimized with the result that high-resolution pattern printing is attainable. Therefore, the exposure apparatus can be operated in a most suitable and efficient manner, which is best suited to the characteristics of the pattern to be printed and to the desire of the operator who handles the apparatus.
While the invention has been described with reference to the structures disclosed herein, it is not confined to the details set forth and this application is intended to cover such modifications or changes as may come within the purposes of the improvements or the scope of the following claims. | A projection exposure apparatus includes a projection lens system for projecting a pattern of an original upon a workpiece, an illumination optical system for illuminating the original with a light having a predetermined central wavelength, and a bandwidth changing arrangement effective to change the bandwidth of the light irradiating the original. | 6 |
This Application is a CIP of Provisional Application Ser. No. 60/126,755, filed Mar. 29, 1999.
TECHNICAL FIELD
The present invention relates to methods of recovering valuable components present in waste streams and effluents from anaerobic digestion systems, and more particularly comprises a partitioning method for recovering salts of volatile fatty acids, as well as undenatured enzymes in valuable forms.
BACKGROUND
The coexistence of small organic species, like acids and alcohols, with protein molecules is a common occurrence in various processing streams. For example, fermentation broths usually contain acids, vitamins and enzymes and are formed in conjunction with the manufacture of some industrially important proteins or in the cultivation of bacteria or fungi as extracellular components. Similar materials are found in the sera of animals and humans and as effluents in waste streams from meat processing streams, as well as in anaerobic digester effluents, (eg. from cattle rumens for instance), and all said examples present industry with a continuing disposal problem.
Further, it is known that said waste streams and anaerobic digester effluents typically contain components including valeric, acetic, propionic and butryic volatile fatty acids, and enzymes such as alpha-amylase and cellulase, as well as other proteins, many of which components are valuable and can be sold if available in separated-out, usable, form. And, as an added benefit, where such components are separated-out of waste streams or anaerobic digestion system effluents, the remaining waste or effluent can be easier to process to the point it can be disposed of, as the BOD requirement is often reduced.
As well, regarding waste streams or effluents such as are developed in meat processing plants, the recovery of useful chemicals therefrom, or their complete treatment is often mandated by local or federal regulations, (eg. where acetic and other carboxylic acids are present in the waste materials).
Beneficially, separation of valuable acids and/or enzymes can convert a waste stream into a value added stream and thereby create positive cash flow where otherwise disposal costs are required.
With the foregoing in mind, it is noted that adsorption combined with extraction, has long been the method of choice when other conventional separation methods prove too expensive and/or are energy intensive.
As described by Eyal and Canari in an article titled “Ph Dependence of Carboxylic and Mineral Acid Extraction by Amine-based Extractants: Effects of pKa, Amine Basicity, and Diluent Properties”, Ind. Engng. Chem. Res. 34:5 1789-1798 (1995); and by Ganguly and Goswami in an article titled “Surface Diffusion Kenetics in the Adsorbtion of Acetic Acid on Activated Carbon”, Sep. Sci. Tech. 31:9 1267-1278, (1996); adsorption and extraction are commonly used methods for the separation of acids from dilute streams.
Low molecular weight aliphatic carboxylic acids appear in many industrial and effluent streams and the recovery thereof by solvent extraction, with or without reaction, has been studied by Shama and Jagirdar and reported in an articel titled “Recovery and Separation of Mixtures of Organic Acids from Dilute Aqueous Solutions”, J. Sep. Proc. Technol., 1:2 40-43, (1980).
Amine-based extractants, because of their effectiveness and selectivity, are favored over other extractants in the recovery of acids from aqueous solutions as reported in an article titled “Extraction of Carboxylic Acids With Tertiary and Quaternary Amines: Effect of pH”, Yang et al., Ind. Engng. Chem. Res. 10:6 1335-1362, (1991).
Partitioning studies of various organic compounds using both adsorbents and extractants have also been documented by King in an article titled “Acid-base Equilibria” in the encyclopedia of Physical Chemistry and Chemical Physics, Pergamon Press, Oxford (1965); and in an article titled “Coupling Ion Pair Extraction With Adsorbtion for the Separation of Acidic Solutions for Water”, Payne and Ramarkrishnan, Ind. Eng. Chem. Res., (1995).
Adsorbents are generally employed in separations using column liquid chromatography for proteins and other organic solutes. Adsorption of molecules of different sizes and surface charges has been investigated by Tien in an article titled “Adsorbtion Calculations and Modeling”, Butterworth-Heinemann, Mass. (1994).
Recently amine-based experiments to extract and recover alpha-amylase from reverse micellar solutions has been reported by Chang and Chen titled “Purification of Industrial Alpha-amylase by Reversed Micellar Extraction”, Biotech, Bioengng, 48, 745-748, (1995).
It is noted that a use for salts of (APB's) is as de-icers as discussed in an article titled “Chemical Deicers and the Environment”, D'Itrl, Lewis Publishers, Mich., (1992).
Further, commonly utilized de-icers are more corrosive than are esters, such as an acetate, as reported by Reisinger and King in an article titled “Extraction and Sorbtion of Acetic Acid at pH Above pKa to form Calcium Magnesium Acetate”, Ind. Sep. Proc. Technol., 34, 845-352, (1995), hence use of metal esters such as CaMg Acetate, CaMg Propionate etc. can be projected as providing environmentally friendly results.
It is specifically noted that for any dilute aqueous stream which contains acids and enzymes, the operating parameters for separating out the acids are different than those for recovering the enzymes and importantly, successful simultaneous separation of both acids and proteins has not before been reported. The present invention, however, teaches that uptake of carboxylic acids and enzymes, alpha-amylase and cellulase from solution can be achieved, where the enzymes are preferentially sequestered, either by leaving the acids in solution or by partitioning the acids into a different phase. And, since unlike solutes do not compete simultaneously with the non-aqueous phase (organic or solid), high percentage separations for acids and enzymes can be achieved.
Present invention experimental work has focused on acetic, propionic and butyric acids and protein compounds including alpha-amylase arid cellulase, (which enzymes are industrially important in degradation of starch and cellulose, respectively), but the approach of using an organic extractant and solid adsorbent to simultaneously separate acids and enzymes is applicable to other systems.
The principal advantage of using organic extractant and solid adsorbent to simultaneously separate acids and enzymes is the ease with which these phases can be separated from an aqueous phase. The extractant and solid phases can be separated from the aqueous phase and the respective phases can be stripped of solutes, allowing the process to be made continuous.
If one solute shows a distinct affinity towards an adsorbent/extractant in the presence of other solutes, then it can be recovered initially.
A Search of Patents has provided a Patent to Monick et al., U.S. Pat. No. 4,765,908 which describes a process and composition for removing contaminants from wastewater. Many chemical compositions are identified for removing heavy metals such as Sodium and Calcium Bentonite, Montmorillonite, calcium carbonate, calcium oxide, calcium hydroxide, lime, aluminum sulfate and a catalist, zirconium. Recovery of enzymes is not a focus.
U.S. Pat. No. 4,675,114 to Zagyvai et al., describes a process for dewatering sludges containing proteinic organic contaminates and for separating solid particles from the aqueous phases. The use of calcium hydroxide and/or magnesium oxide to produce an alkaline sludge pH is mentioned. The use of formaldehyde is described and the methodology does not focus on sequential removal of enzymes followed by removal of other elements.
U.S. Pat. No. 4,629,785 to McCaffery, III, describes a procedure in which proteinaceous material is separated from cationic species by an adsorption process. Converting active microorganisms to inactive form is disclosed.
U.S. Pat. No. 2,171,198 to Urbain et al., describes use of Zinc Oxide to remove and recover fatty acids from waste.
U.S. Pat. No., 3,738,933 to Hollo et al., describes a process for recovering protein from sewage which uses bentonite or kaolin in combination with a calcium compound such as lime milk or calcium hydroxide, aluminum, bi and tri-valent iron.
U.S. Pat. No. 445,055 to Giebermann describes the use of alumina to sequester gluten in slaughter house washings.
U.S. Pat. No. 2,261,923 to Pittman describes use of bentonite to sequester protein from distillery slop.
No known prior teachings, however, provide for partitioning of acids and enzymes into different phases to allow separate undenaturing processing thereof, while leaving unpartitioned solutes in an aqueous phase.
A need is thus identified for economical, easy to practice, methods for separating-out volatile fatty acids, enzyme and possibly other protein components from waste streams and anaerobic digester effluents, and providing said separated-out components are in forms which have economical value.
DISCLOSURE OF THE INVENTION
The present invention provides at least three specifically identifiable modifications of a procedure, the practice of which results in separation of, at least, volatile fatty acids in a valuable salt form which can be, for instance, used as a de-icer. In addition, the present invention procedure can also provide enzymes, (eg. in particular alpha-amylase and cellulose), in undenatured, separated-out form.
The First variation of the present invention can be recited as a method of providing “paunchate” comprising salts of volatile fatty acids comprising, in any functional order, the steps of:
a. providing a waste stream or anaerobic digester system effluent which comprises volatile fatty acids typically including acetic and/or propionic and/or butyric acids, as well as proteins and/or enzymes typically including alpha-amylase and/or cellulase;
b. optionally separating-out particulate solids therefrom;
c. mixing oxides comprised of at least one selection from the group consisting of: (any Group IIA and Group IIB Metal Oxide), into the solution resulting from practicing step a. and optionally step b., such that “paunchate” comprising volatile fatty acid salts is provided in a separated-out form.
The Second variation of the present invention can be recited as a method of separately providing:
enzyme(s) typically including alpha-amylase; and
“paunchate” comprising salts of volatile fatty acids;
comprising, in any functional order, the steps of:
a. providing a waste stream or anaerobic digester system effluent which comprises a solution of volatile fatty acids including acetic and/or propionic and/or butyric acids, as well as proteins and/or enzymes tyically including alpha-amylase and/or cellulose;
b. optionally separating-out particulate solids therefrom;
c. subjecting the solution resulting from practicing step a. and optionally step b. to enzyme adsorption, and optionally desorption, such that at least alpha-amylase is provided in undenatured separated-out of solution form;
followed by:
d. mixing oxides comprised of at least one selection from the group consisting of: (any Group IIA and Group II Metal Oxide), into the remaining solution resulting from practice of step c., such that “paunchate” comprising volatile fatty acid salts is provided in a separated-out form.
The Third variation of the present invention can be recited as a method of separately providing:
enzymes, typically including alpha-amylase; and
“paunchate”, typically comprising salts of volatile fatty acids;
comprising, in any functional order, the steps of:
a. providing a waste stream or anaerobic digester system effluent which typically comprises a solution of volatile fatty acids including, typically, acetic and/or propionic and/or butyric acids, as well as, typically, proteins and/or enzymes typically including alpha-amylase and cellulase;
b. optionally separating-out particulate solids therefrom;
c. treating the solution resulting from practicing step a. and optionally step b. to organic enzyme extractant in the presence of a selection from the group consisting of: (bentonite and functional equivalents thereto), such that adsorption of at least alpha-amylase onto said selection from the group consisting of: (bentonite and functional equivalents thereto) occurs, optionally followed by causing desorption of said alpha-amylase from said selection from the group consisting of: (bentonite and functional equivalents thereto), such that at least said alpha-amylase is provided in an undenatured separated-out of solution form;
said method further comprising:
d. mixing oxides comprised of at least one selection from the group consisting of: (any Group IIA and Group IIB Metal Oxide), into the remaining solution resulting from practice of step c., such that “paunchate” comprising volatile fatty acid salts is provided in a separated-out form, accompanied by recovery of said organic enzyme extractant.
In any of the foregoing examples, the “paunchate” resulting from the practice thereof can consist of selection(s) from the group consisting of:
calcium-valerate;
calcium-acetate;
calcium-propionate;
calcium-butyrate;
calcium-magnesium-acetate;
calcium-magnesium-propionate; and
calcium-magnesium-butyrate.
Further, in any of the foregoing examples, the separation of cellulase can also be performed, with a preferred approach thereto being by a size exclusion chromatography procedure.
It is also noted that any of said methods can provide a solution remaining after practice of the last step therein which has a reduced BOD as compared to the original waste stream or anaerobic digester system effluent as provided in step a.
It is further noted that the volatile fatty acid salt “paunchate” produced by any of the above methods is suitable for use as deicer.
The invention will be better understood by reference to the Detailed Description Section of this Specification, in conjunction with the Drawings.
SUMMARY
It is therefore a primary purpose and/or objective of the present invention to provide economical, easy to practice, methodology for separating-out volatile fatty acids, enzyme and possibly other protein components from waste streams and anaerobic digester effluents, and providing said separated-out components in forms which have economical value.
It is another purpose and/or objective of the present invention to provide systems for practicing the methodology.
Other purposes and/or objectives of the present invention will become clear from a reading of the Specification.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a system for practicing a present invention Method,
FIG. 2 shows a system for practicing a present invention Method.
FIG. 3 shows a system for practicing a present invention Method.
FIGS. 4 a , 4 b and 4 c show additional possible present invention system configurations.
FIG. 5 shows the effect of the pH of a solution on the conversion of acetic, propionic and butyric acids, (APB's) into salts.
FIG. 6 shows that alpha-amylase activity was retained up to about 50% conversion of APB's into salts, while cellulase activity as lost even at very low conversions.
FIG. 7 shows partition isotherms for three different volatile fatty acid cases.
FIG. 8 a shows partition isotherms for acetic acid in the presence of sodium acetate, and for sodium butyrate, are similar.
FIGS. 8 b and 8 c shows partition isotherms for propionic and butyric acids, respectively.
FIG. 9 a shows mass spectrometry data at pH 4.5 before extraction of acetic acid in the presence of sodium butyrate.
FIG. 9 b after extraction of acetic acid in the presence of sodium butyrate.
FIG. 10 shows a flow sheet for simultaneous separation where bentonite was used for enzymes uptake and Alamine 336 was used for the extraction of acids.
FIG. 11 depicts separation acheived from aqueous solution for alpha-amylase, cellulase and acid.
DETAILED DESCRIPTION
A system for practicing the First present invention Method as disclosed in the Disclosure of the Invention Section herein, can be appreciated by referral to FIG. 1 . FIG. 1 shows a waste stream or effluent from an anaerobic digester system being entered to a vessel (A) in which exemplary ZnO, CaO and or MgO is/are also entered, such that therein is formed, in a separated-out form, salts of volatile fatty acids, (ie. “paunchate”). It is noted that CaO/MgO is preferred but that many oxides can be utilized.
A system for practicing the Second present invention Method as disclosed in the Disclosure of the Invention Section herein, can be appreciated by referral to FIG. 2 . FIG. 2 shows a waste stream or effluent from an anaerobic digester system being entered to a vessel (B), in which vessel (B) is present an adsorbant which adsorbs enzymes (eg. alpha-amylase). The results obtained in vessel (B) are subjected to desorption in vessel (C) to provide separated-out alpha-amylase. The remaining mixture sent to vessel (D) wherein exemplary ZnO, CaO and or MgO is/are also entered, such that therein is formed in a separate form salts of volatile fatty acids (ie “paunchate”). It is noted that CaO/MgO is preferred but that many oxides can be utilized.
A system for practicing the Third present invention Method as disclosed in the Disclosure of the Invention Section herein, can be appreciated by referral to FIG. 3 . FIG. 3 shows a waste stream or effluent from an anaerobic digester system being entered to a vessel (E) along with an organic extractant, in which vessel (B) is present an adsorbant which adsorbs enzymes (eg. alpha-amylase). The results obtained in vessel (B) are sent to vessel (F), (note that vessels (E) and (F) can be a single, combined function unit), and are subjected to desorption in follow-on vessel (C) to provide separated-out alpha-amylase, and adsorbant. The remaining mixture sent to vessel (H) wherein exemplary CaO and or MgO is/are also entered, such that therein is formed in a separate form salts of volatile fatty acids (ie “paunchate”). Also indicated is recovery of the extractant originally entered to vessel (E). It is noted that CaO/MgO is preferred but that many oxides can be utilized.
FIGS. 4 a , 4 b and 4 c show additional possible present invention system configurations.
FIG. 4 a shows sodium salts can be formed from the reaction of volatile fatty acids (VFA's) with sodium hydroxide. The carboxylates thus formed are very soluble in water and the literature reports therapeutic usage for these salts as described in U.S. Pat. No. 5,563,173 to see Yatsu and Ranganna (1996) as anti-proliferative agents. The salt solubility decreases for oxides of calcium, magnesium and zinc.
FIG. 4 b shows a system including a separator for use in manufacturing calcium-magnesium acetate.
FIG. 4 c shows a system which allows addition of an extractant in a different route to produce salts of acetic, propionic and butyric acids, (ie. APB's). With the addition of an organic extractant, such as an amine, the acids can be quantitatively complexed into an organic phase. Later the organic phase can be stripped to recover the carboxylic acids and the extractant. Following the stripping step, the metal oxides can be added to complete the reaction and provide Calcium-Magnesium-Paunchate (CMP).
EXAMPLES
With the preceding focused presentation in mind, attention is now turned to providing additional detail and insight to the basis of the present invention. The first example involves use of high purity (99+%) calcium, magnesium and zinc oxides (purchased from Mallinckrodt), a Spectronic 20D system was utilized to measure adsorbance for enzymatic assays. Rumen samples from grain-fed fistulated cows were collected one hour after feeding. The samples were filtered through cheese cloth and then centrifuged at 3000 g for 30 minutes to separate any remaining particulate matter. For gas chromatographic analyses, samples were further centrifuged at 20,000 g for 10 minutes and filtered through a 0.45 micron filter to remove any micro-particles. In the case of model solutions, acetic, propionic and butyric acids, (APB's), were mixed in the ratio of 60:25:15, respectively, to provide a final concentration of 10 gm/liter, (which is approximately the same as found in ruminal fluid concentrations). The experimental technique provided that total acid and individual contents of volatile fatty acids were determined by titration with NaOH and by gas chromatography for both model and ruminal samples. Amounts of oxides equal to or greater than those needed stoichiometrically were used for precipitating the carboxylic acids.
Assays for enzymatic activity were measured before and after the precipitation. Regarding alpha-amylase, activity was assayed using p-nitrophenyl maltoheptaoside as the substrate with p-nitrophenol as the reaction product. This technique is discussed in an article titled “Ethylidene Protected Substrate for the Assay of Human Alpha-Amylase”, J. Anal. Chem., 324, 304-308, by Rauscher et al. (1986).
Cellulase activity was determined by the filter paper assay method, which gives reducing sugar as the final product. This technique is discussed by Ghose in an article titled “Measurement of Cellulase Activities”, Pure Appl. Chem, 59:2 257-268, (1987).
It is noted that One International Unit of (IU) amylase and/or cellulase is defined as the amount of enzyme required to release one micro-mole of product per minute, and final activity was expressed in concentration units of International Units per Liter (IU/l).
Equations which describe the reactions, in the case of CaO, are:
CaO+2HAc→Ca(Ac) 2 +H 2 O 1
CaO+H 2 O→Ca(OH) 2 2
Ca(OH) 2 +2HAc→Ca(Ac) 2 +2H 2 O 3
HAc⇄H + +Ac − 4
Ca(Ac) 2 ⇄Ca 2+ 2Ac 31 5
and similar equations apply in the case of Mg, and Zn.
Experiments on both model solution and ruminal fluids determined that acetic, propionic and butyric acid precipitation was best achieved using CaO. When MgO was used, results were not as good, but were better than when ZnO was utilized. Equimolar amounts were used to salt out. Combinations of oxides were also tested, and the results of the experiments are reported in Table 1.
TABLE 1
Conversion
Oxide used
Model solutions
Rumen VFA
CaO
97
70
MgO
88
63
ZnO
55
41
CaO + MgO
99
90
CaO + ZnO
95
85
MgO + ZnO
90
85
It is obvious that precipitation was improved when CaO/MgO pairs were used.
Further, FIG. 5 shows the effect of the pH of a solution on the conversion of acetic, propionic and butyric acids, (APB's) into salts. At less than 100% conversion, mainly at higher pH's, the solutions contain unreacted oxide and hydroxide.
Additional experimentation was conducted with ruminal fluid to determine if the presence of CaO adversely affected enzyme activity. FIG. 6 shows that alpha-amylase activity was retained up to about 50% conversion of APB's into salts, while cellulose activity was lost even at very low conversions. Thus, precipitation of volatile fatty acids (VFA's) might be feasible where alpha-amylase is to be simultaneously recovered, but not where cellulase is to be recovered. It is thus greatly preferable to separate protein/enzymes from ruminal solution, prior to precipitation of VFA's therefrom, if enzyme activity is to be preserved.
From the preceding, it can be concluded that oxides of calcium, magnesium and zinc convert carboxylic acids into their salts, with calcium oxide CaO being preferred. However, the use of a CaO/MgO oxide pair provides additional utility in conversion of ruminal fluids VFA's into salts, which salts show promise as environmentally friendly de-icing agents. Further, it can be concluded that where enzymes are to be recovered in an active form, separation thereof prior to VFA precipitation is preferable.
The present invention further documents simultaneous separation of volatile fatty acids and enzymes from dilute aqueous streams coupling adsorption and extraction. It has already been demonstrated herein that separation of enzymes, from a waste stream or ruminal fluid, is necessary to preserve enzymatic activity where precipitation of volatile fatty acids present therewith, as their salts, is to be performed. Thus the present invention is further reported as comprising acid extraction using Alamine 336, coupled with adsorption of enzymes onto Bentonite. This approach provides three distinct phases which are easily separated by centrifugation. Acids are found primarily in an organic phase, while most alpha-amylase is found in an aqueous phase. Cellulase shows a high affinity for the adsorbent and is found primarily in a solid phase. It was also noted that salt ions coexistent with acidic solutions affect the extraction of single acids or mixtures of acids as a result of a combination of chain lengths and the nature of the salt ions in solution.
Results reported in the following were achieved using acidic solutes of an analytical grade obtained from Sigma. Alamine 336 was obtained from Henkel Corporation. A 1:1 volume ratio of aqueous to organic phase was used throughout the study and the acid concentration for either single or multiple solutes was kept below 100 mM. The alpha-amylase source was B. Licheniformis and that of cellulase from T. Viride, both acquired from Sigma. As mentioned before, alpha-amylase activity was assayed using p-nitrophenyl maltohepaoside as substrate as described in the previously cited article by Rauscher et al. (1986)
The cellulase activity was determined by the filter paper assay method which gives reducing sugar as the final product as described in the previously cited article by Ghose (1987).
And again, one International unit of amylase and cellulase is defined as the amount of enzyme required to release one micromole of product per minute. The final activities were expressed in concentration units as IU/Liter.
Acids were quantified by titration and also by gas chromatography. A HP 6890 GC, equipped with a FID, capillary inlet system and GC protector was used throughout the analysis. The chromatograph was controlled and interfaced to a HP Vectra PC and the HP 3365 ChemStation quantitative analysis and report making software. The separation was carried out with a 0.25 mm ID×30 m×0.25 micron HP-Innowax capillary column bonded with a cross-linked polyethylene glycol. Helium was used as the carrier gas. Sample solution (ca. 1.0 microliter) was loaded into the injection port at 280 degrees Centigrade with a split ration of 1:40 with an electronic pressure control. The inlet pressure of the carrier gas was controlled at 24 psi and the linear velocity was 42 cm/sec at the initial column-oven temperature of 120 degrees Centigrade. The initial oven temperature was held for 1 minute and then programmed up to 265 degrees Centigrade at 10 degrees Centigrade/ minute and held for 2 minutes at the final temperature. The eluent was detected with a FID at 300 degrees Centigrade.
Sorbtion studies of enzymes with bentonite were carried out at different pH's to see the optimal uptake from solution without acidic solutes. The amount of bentonite used in the experiments was fixed at 4 gm/liter, the capacity at which the percentage adsorption was at least 90. The concentration range for alpha-amylase was from 100 to 500 IU/Liter and that of cellulase from 15 to 75 IU/Liter. Cellulase showed good adsorptivity onto bentonite and other adsorbents tested were also effective. But, its desorptivity was very poor. By contrast, alpha-amylase was able to desorb by either changing the pH or the ionic strength of the solution. Also, the carboxylic acids showed little or no affinity towards bentonite, (less than 2% of the total acid taken was adsorbed), but were adsorbed to varying extents with other adsorbents.
Table 2 shows the behavior of alpha-amylase adsorption onto bentonite with varying pH at two different ionic strengths. The uptake of alpha-amylase is a strong function of pH and decreases beyond neutral pH, and also below its isoelectric point. Acids and their corresponding salts affect the ionic strength of solution. As also shown in Table 2, the influence of ionic strength as compared to pH is small and adsorption variations caused in ionic strength can be neglected for the range of acid concentration examined.
TABLE 2
I = 50 mM
I = 100 mM
pH
% adsorbed
pH
% adsorbed
5.25
88
5.35
88
5.65
100
5.62
94
6.0
97
5.95
97
6.28
94
6.2
87
6.67
86
6.45
80
6.92
80
6.95
72
As regards the separation of acids, FIG. 7 shows partition isotherms for three different cases. The equilibrium acid concentration in the organic phase increases linearly with aqueous phase acid concentration. Also, the distribution of acids into the amine phase increases as the chain length or hydrophobicity of the acids increases. It is also evident from FIG. 7 that the slopes or distribution coefficients are constant. If the system were ideal, the extraction mechanism of an acid can be expressed as:
Ha a ⇄HA o 6
R 3 N: o +HA o ⇄R 3 N:HA o 7
K p =[HA] o /[HA] a 8
K a1 =[R 3 N:HA] o /{[R 3 N:] o [HA] o } 9
where K p is the partition coefficient and K s1 is the equilibrium constant for Equation 9, and where subscripts a and o refer to aqueous and organic phases. The results in FIG. 7 suggest that K p is constant for the range of acid concentrations investigated. This, however, is rarely the case. The acidic solutes are to some degree found in neutralized form and therefore, the simultaneous occurrence of their salts is not uncommon. As shown in FIG. 8 a , the partition isotherms for acetic acid in the presence of sodium acetate and sodium butyrate are similar. The extraction mechanism for acetic acid with sodium acetate in solution is not different from the case presented in FIG. 7 . Therefore the partition coefficient, K p is still constant. But, when the salt species is sodium butyrate the isotherm is no longer linear, suggesting a dependence of partition coefficient on salt concentration. The equations that should be given to include the effect of salt ions are:
R 3 N:HA o +B − a ⇄R 3 N:HB o +A − a 10
where
K a2 =[R 3 N:HB] o [A −] a /{[R 3 N:HA] o [B − ] a } 11
describes the equilibrium relationship for the exchange of the long chain salt ion for the low molecular weight ion. A similar result is depicted in FIGS. 8 b and 8 c for propionic and butyric acids. The non-linearity of the partition coefficient also suggests that the formation of diners in the organic phase with low dielectric strength is also a possibility:
Ha o ⇄(HA) 2o 12
and
K a3 =[(HA) 2 ] o /[HA] 2 o 13
as described in a previously cited article by King (1965).
FIG. 9 a shows mass spectrometry data at pH 4.5 before, and FIG. 9 b after, extraction of acetic acid in the presence of sodium butyrate. It is apparent from FIGS. 9 a and 9 b that both acetic and butyrate ions are being extracted. Furthermore, the extraction of salt ions exclusively into the amine phase is ruled out since Alamine 336 does not form complexes with these ions, as described in the previously cited article by Yang et al. (1991).
Therefore, the exchange of butyrate ion with acetate ion should take place in the aqueous phase. From the above results for the extraction of a mixture of acidic solutes, it is clear that the uptake of an individual acid depends upon its chain length and on the nature of all of the salts in solution as well.
For other adsorbents tested, the uptake of acids was quite good, (90%+), as shown in Table 3, although a small amount of alpha-amylase adsorption onto them was observed. Separation of acids and enzymes in a single processing step using sieves and bentonites is not easy because the system now contains two solid adsorbents. Therefore, density difference is a key factor if the simultaneous separation of analytes is undertaken.
TABLE 3
Material
% uptake
3 Å sleve
94; 97; 99
10 Å sleve
92; 95; 98
zeolite
92; 96; 99
Additional work was undertaken and for this case the compounds which gave the best results for acids and enzymes were used. Therefore, bentonite was used for enzymes uptake and Alamine 336 was used for the extraction of acids. The corresponding flow sheet for simultaneous separation is shown in FIG. 10 . The solution mixture consisting of alpha-amylase, cellulase, acids and bentonite was mixed thoroughly and phases were separated by centrifugation. The corresponding three (3) phases are shown on the right hand side of the flow sheet. The top phase, being lighter, is the amine phase with acids. The bottom phase, being heavier, contains the solid adsorbent with enzymes. The aqueous phase, after equilibration, should contain the unpartitioned solutes. As discussed earlier, the acids extraction is more than 70% complete, whereas for alpha-amylase there is greater than 80% adsorption onto bentonite along with cellulase. The alpha-amylase can be stripped from bentonite into the aqueous phase by shifting pH or by using an eluant with high ionic concentration. In this work, it was desorbed by increasing the solution pH to 8.1. The cellulase showed poor desorptivity and thus was enriched in the adsorbent phase. FIG. 11 depicts results for alpha-amylase, cellulase and acid. Importantly, this process can be made continuous, since the phases are easily separable because of density differences. Further, it is evident that the separation is pH dependent.
It is further noted that low solution pH, though attractive because of high adsorption of the enzyme, affects the amount of acids extracted to the organic phase. Different desorption mechanisms from bentonite for alpha-amylase and cellulase proved useful and a high separation factor between them was achieved. From FIG. 11, it appears that a desirable pH would be close to 6.5, where a good degree of separation of all the solutes will be realized. Moreover, the enzymes are stable in contact with the organic phase which is yet another feature of the process that favors the use of extractant.
In conclusion, it can be stated that the principal advantage of using organic extractant and solid adsorbent to simultaneously separate acids and enzymes is the ease with which these phases can be separated from the aqueous phase, and the ease with which the respective phases can be stripped of solutes, thereby allowing the process to be made continuous. Further, useful analytes like volatile fatty acids and enzymes can be separated utilizing differences in their affinity for various media. At pH's close to neutral conditions the salt ion concentration increases and this affects extraction of acids because of a combination of factors such as chain length, type of salt ion, and hydrophobicity of the acid itself. Thus, salt ions enhance the extraction of acids and also confer stability to the enzyme solution. Further, a process involving adsorbent and extractant can be used to achieve a high degree of separation of acids and enzymes simultaneously. By choosing a system with materials of different densities, the process becomes easy and can be made continuous for large scale operation. Thus, recovery of chemicals from effluent streams is a viable option not only to meet environmental regulations but also as a method for successful management of wastes.
Having hereby disclosed the subject matter of the present invention, it should be obvious that many modifications, substitutions, and variations of the present invention are possible in view of the teachings. It is therefore to be understood that the invention may be practiced other than as specifically described, and should be limited in its breadth and scope only by the Claims. | A method for producing at least one metal salt of a fatty acid is disclosed. The process first obtains from animal rumen, ruminal fluid containing at least one fatty acid. Next, at least one metal oxide is added to the ruminal fluid. One metal salt of a fatty acid is formed from the addition of these two components. Lastly, the process involves recovering at least some of the at least one metal salt of a fatty acid. The ruminal fluid also contains enzymes which are isolated in the process. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application claims priority to co-pending U.S. provisional application Ser. No. 60/058,627 filed Sep. 11, 1997.
FIELD OF THE INVENTION
This invention is concerned with pre-completion destructive testing of plastically deformable materials. More particularly, this invention relates to the testing of the durability of more than one C4 or other solder connection joint during one testing interval.
BACKGROUND OF THE INVENTION
The use of materials comprising plastically deformable materials has increased in a number of industries. Solder balls are an example of an object comprising a plastically deformable material. The use of solder balls is wide-spread in the microelectronic packaging industry. The testing of solder ball assemblies in microelectronic packages is well known in the industry. Various techniques exist which test the strength and fitness of solder ball assemblies. Some methods involve in-line testing and others are after process testing methods. Most in-process methods are destructive, the in-line methods also tend to be slower in that one solder ball assembly at a time is tested. Current testing methods involve testing the force required to "lift" or shear a solder ball from its original location, such that the entire solder ball assembly is relocated. While it is possible to test more than one solder ball assembly at one time, since an accurate calculation of the force necessary to move each individual solder ball is difficult to determine when more than one is moved at a time it would be advantageous to explore the possibility of other testing techniques.
Other methods of testing the fitness of solder ball assemblies involve testing the assemblies after processing is complete. The after process methods can be both destructive and non-destructive. The after processing testing can be disadvantageous because large quantities of product can be produced before the non-conformity is identified. Additionally, in high production scenarios where product is shipped quickly, non-conforming product may already have been shipped before the non-conformity is discovered.
The time and resources needed to test solder ball assemblies increases as the complexities of the underlying packages increases. In the case of packages having grid arrays of solder ball assemblies, both ceramic and ball grid array packages, the amount of space between the solder balls decreases with each generation of packages and the complexity of the circuitry in the packages increases with each passing generation. The time and difficulty of in line testing each solder ball individually using current methods makes it difficult to further process the chips at the speed necessary to ensure that the packages can be produced using high speed processing techniques. Thus there remains a need for a method of testing solder ball assemblies where more than one solder ball assembly is tested during one testing interval. There also remains a need for a method of testing solder ball assemblies where the testing can occur in-line before large quantities of product are produced.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide a method for testing the integrity of more than one test object in a testing cycle.
It is another object of the present invention to provide an apparatus for testing the integrity of more than one test object in a testing cycle.
In accordance with the above listed and other objects, we invent a method for testing the integrity at least two test objects, each object comprising a plastically deformable material, comprising the steps of:
a. contacting a moving means with the objects at a first point in time, the moving means at a first position and the objects at a first position, the moving means having a shaped portion;
b. shifting at least a portion of the objects to a second position at a second time, subsequent to the first time, wherein at least a portion of the objects were displaced during the interval between the first time and the second time;
c. evaluating the objects after the shifting in step b. We also invent an apparatus for use with the method.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other features, aspects and advantages will be more readily apparent and better understood from the following detailed description of the invention, in which:
FIG. 1 is a top down view of the test objects being acted upon in the method and apparatus of the present invention.
FIG. 2 is a view of one depiction of an element of the apparatus of the present invention.
FIG. 3 is a front view of one embodiment of an element of the apparatus of the present invention.
FIG. 4 is an isometric view of one step of the method of the present invention.
FIG. 5 is an isometric view of a variety of shapes of a diameter that may be encountered while practicing the method and apparatus of the present invention.
FIGS. 8a and 8b are isometric representations of the method of the present invention.
FIG. 9 is a top down view of test objects that have undergone the method of the present invention.
FIGS. 10a and 10b are another cross-sectional view of a method of the present invention.
FIGS. 10c and 10d are yet another isometric view of a method of the present invention.
FIG. 11 is yet another cross-sectional view of the method of the present invention.
FIG. 12 is another view of the alternative apparatus of the present invention.
FIG. 13 is yet another view of an alternative apparatus of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
The present invention discloses a method and apparatus to test the operability of a plurality of test objects during one testing interval. Generally, the apparatus of the present invention, interacts with surfaces having a plurality of protrusions. Specifically, the primary embodiment of the apparatus interacts with a surface having a plurality of plastically deformable bodies. For the purposes of the present discussion, all of the protrusions will be referred to as plastically deformable bodies, unless it is indicted otherwise. Also, for the purposes of the present discussion, the surface having the plastically deformable body will comprise a ceramic, unless it is indicated otherwise. At least two of the plastically deformable bodies will be designated as test objects. It is not required that all of the plastically deformable bodies on a surface be test objects. The test objects are usually presented in a pattern. For example, the test objects could be presented so that rows of test objects are identifiable. However, it should be noted that a definite pattern need not exist for the current method to be operable. It is only necessary that more than one test object be tested during each test interval. In a preferred embodiment all of the plastically deformable bodies on a surface would be test bodies. Additionally, the plastically deformable bodies may comprise more than one material and comprise more than one portion. The plastically deformable body may be a solder ball having a ball limiting metallurgy in contact with the surface.
The apparatus of the present invention includes a moving means. The moving means contains a shaped object. The configuration of the shaped object should be such that it is capable of contacting each test object involved in an individual test interval.
An example of the present apparatus is given below. The surface, 1, containing the test objects, 5, would preferably be arranged in rows, r, of a predetermined length, a, as shown in FIG. 1. The test objects would be of substantially the same size and shape and preferably, the spacing between the rows, t, would be in a repeated pattern or a predetermined configuration. The shaped object, 8, of the moving means as shown in FIG. 2 would preferably be rectangular and the depth of the shaped object would be less than t, the distance between the rows of test objects. The height of the shaped object would be greater than the height of the test objects and the width of the shaped object would be at least about equal to a, the length of a row of test objects. The shaped object need not be rectangular, the only shape requirement is that the moving means not contact the test objects such that a significant pressure is exerted on the test objects prior to the movement during the testing interval. It is also preferable that the shaped object be placed at an adjustable fixed distance from the surface containing the test objects.
As shown in FIG. 4, prior to a test interval the moving means should be placed such that the distance between the surface, 1, and the lowest effective edge, 15, of the moving means, 8, is at least about 1% and at most about 50% of the diameter, d, of the test objects. The lowest effective edge, 15, of the moving means, 8, must be at least about 1% of the diameter so that the method of the invention does not provide data that corresponds to the torquing that would occur from a movement of the test object if the pressure is exerted at what is essentially the surface containing the test objects, sometimes referred to as peeling. By diameter it is meant the diameter of the test object where it contacts the surface containing the test objects. Examples of some, but not all, possible diameters are shown as A, B C, E and F in FIG. 5. Preferably, the height of the lowest effective edge is at least about 5% and at most about 30% of the diameter, d, of the test objects. By lowest effective edge it is meant that in a case where the shaped object of the moving means is not a rectangular shape, the lowest effective edge would be the edge corresponding to the plane defined by q, the side of the moving means, 8, which faces the test objects, as shown in FIG. 4. In a preferred embodiment, all of the plastically deformable bodies would be test objects and the moving means would be shaped so as to facilitate the testing of all of the test objects uniformly in one test interval. It should be noted that the apparatus and method of the present invention are not dependent on the shape of the test objects, the present method and apparatus are operable for any shape test object. While it is preferred that the test objects be spherical or columnar, the present invention involves the use of the diameter of the test object where it connects to the surface containing the test objects. It is also preferred that the test objects be solder balls.
The moving means may contain a distancing portion, 10, in operable communication with the shaped object as shown in FIG. 3. The distancing portion can be integral or separate from the shaped object. The distancing portion functions to position the shaped object such that the shaped object does not contact the surface containing the test objects. Preferably the shaped object does not contact the surface containing the test objects. In a preferred embodiment the distancing portion would be a protrusion, a wire or a similar mechanical means. In a more preferred embodiment, the distancing portion would not contact the test objects.
The method of testing defined in the present invention evaluates the operability of plastically deformable bodies. The method provides information regarding the failure of the plastically deformable bodies in the area surrounding connection point between the plastically deformable body and the underlying surface. Failures of different types of plastically deformable bodies, for example those attached to ceramic, organic and polymer surfaces or attached to metal pad on ceramic, organic and polymer surfaces might manifest in different manners. However, within a type of plastically deformable bodies, operable plastically deformable bodies will respond similarly. Deviations from an acceptable response of an operable plastically deformable body can be established and failures identified.
All further discussion and examples will presume that the surface containing the plastically deformable bodies is substantially parallel to the X axis. If the surface is not substantially parallel to the X axis the proper relationships will have to calculated based on the examples where the surface is parallel to the X axis. The method of the present invention is not dependent on the surface being parallel to the X axis. An operable plastically deformable body will react in a particular manner to the test. All plastically deformable bodies not reacting in the particular manner, while not necessarily defective, will be considered as being of a significant risk of being defective. A plastically deformable body in communication with a metallic interface on a ceramic surface will be used to illustrate the instant invention. An operable plastically deformable body, will relocate in the manner shown in A of FIG. 9, when the method of the instant invention is employed.
As shown in FIG. 10a, before the method of the present invention, the plastically deformable body has an axis, K, which, preferably, is the axis substantially parallel to the surface at a point of the largest diameter above the lowest effective edge, 15, of the moving means, 8. The plastically deformable body, 5, also has an axis, L, which is, preferably, the axis perpendicular to the surface at a point of the largest diameter above the lowest effective edge. A portion of the plastically deformable body, 5, on the surface, 1, is identifiable as an area of attachment, 3, between the plastically deformable body, 5, and the surface. In a preferred embodiment, the area of attachment, 3, of the plastically deformable body, 5, is below the lowest effective edge, 15, of the moving means, 8. After the testing interval, there will be two parts to each plastically deformable body, as shown in FIG. 10b. The upper portion, 100, has been shifted in relation to the lower portion, 105. The lower portion, 105, roughly conforms to the area of attachment, 3, in FIG. 10a. The upper portion has a first axis, L1, and the lower portion has a second different axis, L2. A plastically deformable body will have a lower portion, 105, where the lower portion has an exposed surface, M, substantially parallel to axis K. The exposed surface will be created by the interaction of the moving means and the surface containing the test objects. For example, an optimal reaction for an operable plastically deformable body comprising solder on a ceramic surface occurs when substantially all of the points on the exposed surface, M, contact any single plane parallel to axis K, when the parallel plane contacts at least one point on the surface. However, it should be noted that the response from a conforming plastically deformable body may be dependent on the combination of the type of body, the interface between the body and the surface, and the surface itself. The particular operator for any particular application and any combination of plastically deformable bodies and surfaces can determine at what point a deviation from the reaction constitutes a failure of the test.
As another example, where a polymer comprising surface has a plastically deformable body attached, a difference between the response to the test method for an operable plastically deformable body and the reaction of a non-operable deformable body is generally observable. In the case of a plastic deformable body on a polymer surface, an optimal reaction is usually identifiable where the entire plastic deformable body, 50, is ripped from the surface, 55, containing the plastic deformable body, the plastic deformable body on a polymer remains as a single unit, as shown in FIG. 10d. An optimal reaction of a plastic deformable body on a polymer can be exemplified where the integrity of the interface is stronger than the cohesive strength of the polymer, and therefore the surface containing the plastic deformable bodies rips. A non-conforming reaction would be a reaction that is not substantially similar to that shown in FIG. 10d, for example the reaction shown in FIG. 10c. FIG. 10c shows that the plastically deformable body did not react by ripping, instead, the plastically deformable body does not move as a single unit and a portion of the plastically deformable body, 60, remains on the surface, 55.
In a preferred embodiment the test objects would be solder balls that have been soldered to the surface. In a preferred embodiment, for any type of plastically deformable body where the reaction to the testing method of the present invention does not conform to a predetermined optimal reaction can be considered as failing the test. An example of an optimal reaction of an operable body for a particular plastically deformable body--surface relationship is shown in A of FIG. 9, where the plastically deformable bodies are solder balls and the surface is ceramic. Examples of reactions not resembling A of FIG. 9 include B and C of FIG. 9. B and C in FIG. 9 shows a plastically deformable body where the movement did not expose a single surface substantially parallel to the surface having the plastically deformable bodies. B and C of FIG. 9 are not the only examples of test reactions that deviate from that shown in A of FIG. 9.
The method of the invention is shown in FIGS. 8a and 8b. At the first point in time, as shown in FIG. 8a, the moving means, 8, is positioned such that it does not exert significant pressure on the test objects, 5, but is capable of contacting the test objects, 5. At the second point in time, FIG. 8b, the moving means, 8, has contacted the test object, 5, and at least a portion of the test object has shifted due to a force exerted on either the moving means or the surface; the force creating a secondary force between the moving means and the surface. The test objects are then inspected and evaluated for their conformance to the optimal reaction to the interaction of the moving means and the surface. In a preferred embodiment the inspection would be optical and the evaluation would require that 100% of the test objects conform with the optimal reaction. In a preferred embodiment, the force is exerted along a plane parallel to K of FIGS. 10a and 10b. In a more preferred embodiment, the force would be exerted on the moving means. In an even more preferred embodiment, the moving means would have a mover arm capable of imparting the force to the moving means. In an even further more preferred embodiment the mover arm, 115, would be located on the side opposite the side of the moving means facing the surface containing the test objects, 110, as shown in FIG. 11.
It should be noted that the amount of force exerted is not necessarily a measured parameter in the method of the present invention. The amount of force exerted must be great enough to cause the contact of the moving means and the test objects and also great enough to cause the movement of the test objects during the test interval. The method of the present invention is operable when the minimum amount of force necessary for movement of the test objects during the test interval is exerted. Additionally, in a preferred embodiment the force would not be great enough to completely separate the lower portion, 105, and the upper portion 100, as shown in FIG. 10b; this can be accomplished by limiting the travel of the moving means and surface.
In a preferred embodiment of the testing interval involving plastically deformable bodies on a ceramic containing surface, the exposed surface, M, of FIG. 10b, will equal at least about 10% of the diameter, d, of FIG. 4. In a more preferred embodiment of the testing interval involving plastically deformable bodies, the exposed surface, M, will equal at least about 30% of the diameter, d. It would be obvious to one skilled in the art that the larger the exposed area, M, the higher the confidence that a reaction equivalent to an optimal reaction denotes an operable plastically deformable body.
In an alternative embodiment of the apparatus, as shown in FIG. 12, the moving means, 4, interacts with a surface, 1, containing the test objects, 5, having a top side, 2, and a bottom side, 3. The test objects, 5, are located on the top side, 2, of the surface, 1. The surface, 1, containing the test objects, 5, is inverted so that the bottom side, 3, is over the top side, 2, and inserted into a holder, 4. In this embodiment, the holder, 4, is part of the moving means and must meet the requirements for a shaped object identified earlier. A cross-sectional view of the holder is shown in FIG. 12, where the test object, 5, is held within the holder, 4, such that the lowest effective edge, 15, of the holder, 4, is within the parameters described for a moving means infra. Additionally, the holder would not exert significant pressure on the test objects when the surface is inserted into the holder. When the apparatus is configured in this manner, any plastically deformable bodies that are separated from the surface, after the application of force as described by the arrow, would be retained in the holder and identifying location where potential non-conformities occurred would be facilitated. In a preferred embodiment, shown in FIG. 13, the holder, 4, is configured such that each test object may fit into an individual pocket, 6, of the holder. These pockets could be of any shape, preferably the pockets would be cylindrical or rectangular. In a preferred embodiment, the pockets would retaining any non-conforming test objects that were separated from the surface.
In a method of the alternative embodiment, during the testing interval, the holder is moved between a first position where the test objects, in a first position, are held within the holder without the holder exerting a significant pressure and a second position where a pressure is exerted on the holder such that the lowest effective edge has contacted the test objects and at least a portion of each test object has moved from the first test object position to a second test object position, as shown by the arrow in FIG. 12. In a preferred embodiment, the movement would be along the X axis as described infra and the holder would then be moved back to the first position.
It should be noted that it is not necessary that the test objects be plastically deformable. A test object that is not plastically deformable that is communication with a surface could be tested by the same method and apparatus of the present invention. In the case of a non plastically deformable test object, reactions signifying a conforming test object could be determined by an operator. Certain types of non plastically deformable test objects will have conforming and non conforming reactions that are substantially similar to the reactions of plastically deformable test objects on polymer surfaces.
While the invention has been described in terms of specific embodiments, it is evident in view of the foregoing description that numerous alternatives, modifications and variations will be apparent to those skilled in the art. Thus, the invention is intended to encompass all such alternatives, modifications and variations which fall within the scope and spirit of the invention and the appended claims. | A method for testing the integrity at least two test objects, each object is made of a plastically deformable material, by a. contacting a moving means with the objects at a first point in time, the moving means at a first position and the objects at a first position, the moving means having a shaped portion; b. shifting at least a portion of the objects to a second position at a second time, subsequent to the first time, wherein at least a portion of the objects were displaced during the interval between the first time and the second time; c. evaluating the objects after the shifting in step b. 22. | 6 |
This application is a continuation-in-part of U.S. patent application Ser. No. 07/721,935, filed Jul. 23, 1991, now U.S. Pat. No. 5,193,936, which is a continuation-in-part of U.S. patent application Ser. No. 07/494,774, filed Mar. 16, 1990, now abandoned.
FIELD OF THE INVENTION
The present application describes treatment methods for metal-bearing materials, especially lead-bearing materials, such as process streams, sludges and slurries, including all types of liquid and solid wastes.
BACKGROUND OF THE INVENTION
Only a few prior art patents have taught the immobilization of lead in different kinds of wastes to make the treated residuals suitable for disposal as special waste in a RCRA approved and licensed landfill facility. For example, some known methods to treat broader groups of metals are shown in U.S. Pat. No. 4,149,968 to Kupiec et al., U.S. Pat. Nos. 4,889,640 and 4,950,409 to Stanforth, U.S. Pat. No. 4,701,219 to Bonee, U.S. Pat. No. 4,652,381 to Inglis, and U.S. Pat. No. 4,671,882 to Douglas et al.
Kupiec et al. teaches the immobilization of heavy metals by treating an alkaline slurry of waste with a mixture of bentonite clay and Portland Cement.
Stanforth teaches a method of treating solid hazardous waste (containing unacceptable levels of lead and cadmium) with reactive calcium carbonate, reactive magnesium carbonate and reactive calcium magnesium carbonate. The patent teaches that addition of water is beneficial to facilitate the mixing of the solid waste with treatment additive and conversion of lead into non-leachable forms. Stanforth further discloses mixing solid waste with lime and carbon dioxide or bicarbonate.
Bonee discloses that calcium chloride, calcium carbonate, gypsum and sodium carbonate are relatively ineffective at reducing the leaching of vanadium and nickel from a petroleum cracking process particulate waste.
Douglas et al. discloses a process for producing a nonhazardous sludge from an aqueous solution by addition of phosphoric acid or an acid phosphate salt, adjusting the Ph to about 5, adding a coagulating polymer and raising the Ph to above 7 through the addition of lime. Then, the process includes dewatering the resulting sludge. This constitutes at least 5 or more steps making it cumbersome, time consuming and expensive.
Inglis teaches a process of treating industrial wastewater which has a pH of 2 and which is contaminated with sulfuric acid, lead, copper and zinc. Calcium carbonate is added along with air to wastewater. This results in neutralization and formation of insoluble metal salts. The process is not applicable to wastes that have a pH of 6 to 9. However, limestone is relatively ineffective in removing lead from hazardous, solid or sludge material. Limestone does not react in the solid materials and metal carbonates that are formed are subject to degradation by acid rain and acidic landfill leachate conditions.
Hazardous wastes containing excessive amounts of leachable lead are banned from land disposal. The regulatory threshold limit under Resource Cons. and Recovery Act is 5 mg/l of leachable lead as measured by TCLP (toxicity characteristic leaching procedure) test criteria, United States Environmental Protection Agency (USEPA) method 1311 (SW-846). Waste materials containing TCLP lead levels in excess of 5 mg/l are defined as lead-toxic hazardous waste and are as such restricted from landfilling under current land ban regulations. The cost of disposing lead toxic hazardous waste materials in excess of $200.00 per ton plus the cost of transporting the hazardous material to landfills for hazardous wastes, which do not exist in every state. This makes the disposal of lead toxic hazardous waste materials very expensive. Therefore, treating the lead-bearing process materials and waste streams to render them non-hazardous by RCRA definition would cut down the costs of transportation and disposal tremendously.
SUMMARY OF THE INVENTION
The present invention discloses a method of treating metal-bearing, especially lead-bearing process materials and lead-toxic hazardous wastes.
The present invention relates to a chemical treatment technology for immobilizing leachable lead in contaminated soils and solid waste materials. According to the present invention, a process for treating lead-toxic solid wastes in order to stabilize the leachable lead is disclosed, comprising the steps of: (i) mixing the solid waste with a sulfate compound, such as calcium sulfate dihydrate (gypsum powder) or sulfuric acid, having at least one sulfate ion for contacting waste particles and reacting with said leachable lead to produce a substantially insoluble lead composition, such as anglesite and/or calcium-substituted anglesite; and, (ii) mixing said solid waste and sulfate compound with a phosphate reagent, such as phosphoric acid, having at least one phosphate ion for reacting with said leachable lead to produce a substantially insoluble lead composition. The treated material from this process is substantially solid in form and passes the Paint Filter Test while satisfying the regulatory standard for TCLP lead. In all instances, application of this process has been found very reliable in meeting the treatment objectives and in consistently decreasing waste volume.
It is an object of the present invention to provide a technology for treatment of lead-containing solid waste and soil that produces an acceptably low level of leachable lead in the final product to comply with the statutory requirements of TCLP and to pass the Paint Filter Test.
Another object of the invention is to provide such a process while producing no wastewater or secondary waste streams during said process.
Still another object of the invention is to provide such a process which also causes the solid waste material to undergo a volume reduction as a result of treatment.
Yet another object of the invention is to cause fixation of the leachable lead in the solid waste that is permanent under both ordinary and extreme environmental conditions.
The invention relates to treatment methods employed to chemically convert leachable metal in metal-bearing solid and liquid waste materials to a non-leachable form by mixing the material with one or a combination of components, for example, lime or gypsum and phosphoric acid. The solid and liquid waste materials include contaminated sludges, slurries, soils, wastewaters, spent carbon, sand, wire chips, plastic fluff, cracked battery casings, bird and buck shots and tetraethyl lead contaminated organic peat and muck. The metal-bearing materials referred to herein which the present invention treats include those materials having leachable lead, aluminum, arsenic (III), barium, bismuth, cadmium, chromium (III), copper, iron, nickel, selenium, silver and zinc. The present invention discloses a process comprising a single step mixing of one or more treatment additives, and a process comprising a two step mixing wherein the sequence of performing the steps may be reversible. The present invention provides a novel way of treating a plurality of metal-contaminated materials at a wide range of pH. The method works under acidic, alkaline and neutral conditions.
The processes of the present invention provide reactions that convert leachable metals, especially lead, into a non-leachable form which is geochemically stable for indefinite periods and is expected to withstand acid rain impacts as well as the conditions of a landfill environment.
A first group of treatment chemicals for use in the processes of the present invention includes lime, gypsum, alum, halites, portland cement, and other similar products that can supply sulfates, halides, hydroxides and/or silicates.
A second group consists of treatment chemicals which can supply phosphate ions. This group includes products such as phosphoric acid, pyrophosphates, triple super phosphate (TSP), trisodium phosphate, potassium phosphates, ammonium phosphates and/or others capable of supplying phosphate anion when mixed with a metal-bearing process material or with a metal-toxic hazardous waste. Depending on the process material or waste (i) matrix (solid, liquid or mixture thereof), (ii) category (RCRA or Superfund/CERCLIS), (iii) chemical composition (TCLP lead, total lead level, pH) and (iv) size and form (wire fluff, shots, sand, peat, sludge, slurry, clay, gravel, soil, broken battery casings, carbon with lead dross, etc.) the metal-bearing material is mixed with one or more treatment chemicals in sufficient quantity so as to render the metal substantially non-leachable, that is, to levels below the regulatory threshold limit under the TCLP test criteria of the USEPA. For lead-bearing material, the treatment additives render the lead below the regulatory threshold limit of 5 mg/l by the TCLP test criteria of the USEPA. The disposal of lead-hazardous and other metal-hazardous waste materials in landfills is precluded under land ban regulations.
It is an object of the present invention to provide a method of treating metal-bearing materials, contaminated soils and waste effluent, and solid wastes containing hazardous levels of leachable metal. It is a further object to provide a method which decreases the leaching of lead in lead-bearing materials to levels below the regulatory limit of 5 mg/l by TCLP test criteria.
It is another object of the present invention to provide a method to immobilize lead to leachable levels below 5 mg/l by TCLP test criteria, through the use of inexpensive, readily accessible treatment chemicals. With this method the leachability of lead is diminished, usually allowing municipal landfill disposal which would not otherwise be permitted.
Yet another object of the present invention is to provide a treatment method for metal-bearing wastes, particularly lead-bearing wastes, which comprises a single step mixing process or a two-step process wherein the sequence of the two steps may be reversed.
Another object of the present invention is to provide a method of treating a wide variety of lead bearing process materials, wire fluff and chips, cracked battery plastics, carbon with lead dross, foundry sand, lead base paint, leaded gasoline contaminated soils, peat and muck, sludges and slurries, lagoon sediment, and bird and buck shots, in order to render the material non-hazardous by RCRA definition, and pass the EPTOX, MEP, ANS Calvet and DI Water Extract tests.
Another object of the present invention is to extend the scope for broad application in-situ as well as ex-situ on small as well as large quantities of metal-bearing process materials or generated waste streams.
The present invention provides a method which converts metal-toxic process materials and hazardous wastes into a material which has a lower leachability of metal as determined by EPA's TCLP test. Such treated waste material can then be interned in a licensed landfill, a method of disposal only possible when the leachability of metal is diminished/reduced to levels below the regulatory threshold limit by TCLP test criteria, e.g., lead below 5 mg/l.
The invention may be more fully understood with reference to the accompanying drawings and the following description of the embodiments shown in those drawings. The invention is not limited to the exemplary embodiments but should be recognized as contemplating all modifications within the skill of an ordinary artisan.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 exhibits the single step mixing method of treatment chemicals metered into the pugmill or Maxon Mixer capable of processing lead hazardous waste materials at rates up to 100 tons/hour;
FIG. 2(a) exhibits the two step mixing method with addition of group one treatment chemicals during step I and addition of group two treatment chemicals during step II;
FIG. 2(b) exhibits the two step mixing method with addition of group two treatment chemical(s) during step I and addition of group one treatment chemical(s) during step II. The reversibility of steps and combination of both steps into a single step is the discovery that is disclosed in this invention and illustrated in FIG. 1 and 2(a) and (b).
FIG. 3 is a block diagram of one embodiment of the treatment technology of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
According to the present invention, leachable lead in treated materials is decreased to levels well below 5.0 mg/l, measured by TCLP test criteria. Waste and process materials having a TCLP lead level in excess of 5 mg/l are considered hazardous and must be treated to be brought into compliance with regulatory requirements. Other metal-bearing materials having leachable may also be treated according to the present invention to achieve acceptable metal levels.
The treatment technology according to another embodiment of the present invention consists of a two step process for treating contaminated soils and/or solid waste materials with chemical treating agents that convert leachable lead to synthetic (man-made) substantially insoluble lead mineral crystals. As used here, "substantially insoluble" means the leachable lead content in the treated waste sample is less than 5.0 mg/l in the extract by the TCLP Test.
Treatment Chemicals and Additives
The treatment chemicals useful in the present invention may be divided into two groups. The addition of water with the additives may facilitate the ultimate mixing and reaction.
A first group, "group one", comprises of a source of sulfate, hydroxide, chloride, fluoride and/or silicates. These sources are gypsum, lime, sodium silicate, cement, calcium fluoride, alum and/or like similar products.
The second group, "group two", comprises a source of phosphate anion. This group consists of products like phosphoric acid (phosphoric), pyrophosphates, triple super phosphate, trisodium phosphates, potassium phosphates, ammonium phosphates and/or similar compounds capable of supplying a phosphate anion.
The first step of this novel process comprises the reaction of leachable lead in contaminated soils or solid waste materials with a gypsum powder, calcium sulfate dihydrate (CaSO 4 .2H 2 O). Calcium sulfate dihydrate powder reacts with leachable and mobile lead species in wastes to form hard sulfates, which are relatively insoluble in water. In the invention, the powder form of dry calcium sulfate dihydrate, or gypsum, is preferred for blending with lead contaminated materials because it provides a uniform cover or dry coating over the surfaces of the waste particles and aggregates under low moisture conditions. The greatest benefit and fastest reaction is achieved under conditions wherein 95% of the powder is passable through a 100 mesh sieve, and the remaining 5% is passable through a 20 mesh sieve.
The amount of gypsum powder employed is typically from 0-30 percent of the weight of solid waste material being treated. The actual amount employed will vary with the degree and type of lead contamination in the waste material or soil, and with the initial composition as well as the condition of the waste material, among other factors.
Alternatively, sulfuric acid, or alum in liquid or powder form can also be used as sources of sulfate ion in certain solid wastes that contain sufficient calcium prior to treatment.
Treatment Method
At least one component from group one is added to the mixing vessel or reactor, preferably as a dry powder although slurries could be pumped under certain circumstances. At least one component from group two is added to the mixing vessel or reactor as either liquid reagent or as granular solid materials.
The ingredients of group one and group two can be added to the hazardous waste materials simultaneously, and they are pre-mixed and added in a single step. Alternatively, the components of group one and two can be added sequentially in a two-step process with either component added first. That is, the two steps may occur in any order. At least one ingredient of group one can be added in step I or step II. Likewise, at least one ingredient of group two can be added in either step I or step II. Enough water may be added to allow good mixing to prevent dust formation, and to permit good chemical reaction. Not too much water is added to solid materials if the treated waste is to pass the paint filter test.
In the first step of the instant process, a thorough and uniform mixing of gypsum powder with the solid waste is accomplished by mixing shredded and screen waste particles with small gypsum particles in, for example, a grizzly or other mixing device. The calcium ions from the gypsum powder displace lead from soil complexes and organic micelles present in the contaminated soil and solid waste material. The following equations (1) and (2) described the reaction of leachable lead with gypsum. ##STR1##
The reaction of lead with gypsum forms a "hard sulfate" which crystallizes into mineral species of the barite family--anglesites and calcium-substituted anglesites--which are insoluble in water. The solubility product of lead sulfate is 1.8×10 -8 , indicating that anglesite crystals would continue to develop over the geologic periods.
In the second step of the process, the solid waste material as amended with gypsum powder is treated with a phosphate-supplying reagent reacts chemically to immobilize the remaining leachable lead. The phosphate-supplying reagent includes phosphate ion sources having one or more reactive phosphate ions, such as phosphoric acid, trisodium phosphate, a potassium phosphate and monobasic or dibasic calcium phosphates.
The quantity of phosphate-supplying reagent employed will vary with the characteristics of the solid waste being treated, including particularly such factors as leachable lead content, total lead, and buffering capacity, among other factors. It has been determined that in most instances a quantity of phosphoric acid up to 30 percent of the weight of the waste material is sufficient. The concentration of phosphoric acid in solution will typically range from about 2-75 percent by weight. The solution and treatment process are maintained above 30° F. to permit the handling of the phosphoric acid as a liquid reagent. Below 30° F., the phosphoric acid tends to gel while water freezes to form ice, thus creating material handling problems.
Free lead, along with calcium ions found in the solid waste (including those imparted through the first step of the process), reacts with the phosphate to form insoluble superhard rock phosphates or calcium substituted hydroxy lead apatites as shown in equation (3a and b): ##STR2##
The phosphate ions are added to the contminated soils in solution form; for example, phosphoric acid may be added to water in amounts ranging from about 2 percent to about 75 percent by weight. Phosphoric acid decomposes carbonates and bicarbonates in waste leading to the synthesis of apatites and evolution of carbon dioxide gas. Destruction of carbonates and bicarbonates contributes to desirable volume reductions.
Although water molecules are generated during the carbonate and bicarbonate decomposition process, it is preferred to have soil moisture at about 10 percent to about 40 percent by weight of the soil in order to accelerate the fixation of the leachable lead with the phosphate ions. At this moisture range, material handling is also easy and efficient. It is apparent from Equations (2), (3a) and (3b) that gypsum and phosphoric acid decompose carbonates and bicarbonates during synthesis of new stable minerals of the barite, apatite, and pyromorphite families in soils (as shown in Table I). Decomposition of carbonates and bicarbonates is usually associated with the evolution of carbon dioxide, formation of hydroxyl group, (OH--), and the release of water molecules. As the water evaporates and carbon dioxide molecules are lost to the atmosphere, the treated waste mass and volume are decreased significantly.
The solid sulfate powder and the phosphate-supplying reagent are added to contaminated soil and solid waste material having a typical moisture content ranging from about 10 percent to about 40 percent by weight. At a moisture level within the foregoing range, the curing time of the treated materials is approximately 4 hours, which provides adequate time for chemical reactions to occur and immobilize the leachable lead species. Crystals of various lead mineral species begin to form immediately, but will continue over long time periods with an excess of treatment chemicals present. This contributes to "self-healing," as noted during treatability studies as well as full scale treatment operations.
Under the foregoing condition, the immobilization of leachable lead occurs in a relatively dry environment because no wet byproducts, slurries or wastewater are produced by the process of the present invention. Operation of the process under relatively dry conditions beneficially allows cost-efficient handling of the contaminated soils and the waste materials. This allows compliance with Paint Filter Test for solid waste required by USEPA and RCRA approved solid waste landfill facilities. Effective mechanical mixing, as by a pug mill or other such mixing device, eliminates the need for diffusion in the nonaqueous solid waste matrix.
The water resistant and insoluble lead minerals synthesized in oils and solid wastes according to this process are stable, and would behave like naturally occurring rock phosphates and hard sulfates. A list of these synthetic lead mineral species and complexes is presented in Table I below, in order of the relative abundance found during characterization of treated soil by x-ray florescence spectrometry, polarized light microscopy (PLM) and scanning electron microscopy (SEM).
TABLE I______________________________________Synthetic Mineral Species of Lead Detected in aTreated Sample (Listed in Decreasing Order of Abundance)______________________________________31-41% Calcium Substituted Hydroxy Lead Apatites, Ca.sub.0.5-1.5 Pb.sub.3.5-4.5 (OH) (PO.sub.4).sub.328-29% Mixed Calcium Lead Phosphate Sulfates, Ca.sub.0.05-0.2 Pb.sub.0.8-0.95 (PO.sub.4).sub.0.15-0.5 (SO.sub.4). sub.0.25-0.7522-22% Mixed Calcium Anglesites, Ca.sub.0.05-0.3 Pb.sub.0.7-0.95 (SO.sub.4)3-6% Anglesites, PbSO.sub.42-7% Lead Hydroxy/Chlor Apatite, Pb.sub.5 (PO.sub.4).sub.3 (OH).sub.0.5 Cl.sub.0.51-3% Pyromorphite, Pb.sub.3 (PO.sub.4).sub.21-2% Organo-Lead Phosphate Sulfate, Humus-o-Pb.sub.3 (PO.sub.4) (SO.sub.4)______________________________________
Some of the chemical reactions that occur during the curing stage, and lead to the development of mixed minerals containing both sulfates and phosphates, are illustrated in equations (4) and (5). ##STR3##
The process of the present invention beneficially decrease the volume of the waste materials through: (i) the evolution of carbon dioxide during the chemical decomposition of carbonates and bicarbonates, upon reaction with the acidic component in gypsum and phosphoric acid, and (ii) hardening and chemical compaction as a result of the synthesis of new minerals which result in changes in interstitial spaces and interlattice structures.
Applications of the process on a lead contaminated soil was associated with pore space decrease from 38.8% to 34.3% by volume. A decrease in pore space was associated with increased compaction of the treated soils and a decrease in overall waste volume ranging from 21.4% to 23.0%. For different waste types, the volume decrease varies with the amount of treatment chemicals used in the process. In another lead toxic solid waste, application of this process resulted in a volume decrease of the order of 36.4% while decreasing the leachable lead to levels below the regulatory threshold.
This reduction in volume of the contaminated soil and the solid waste material makes the process of the present invention particularly beneficial for off-site disposal in a secured landfill by cutting down the costs of transportation and storage space. The process can be accomplished at a cost-efficient engineering scale on-site or off-site for ex-situ treatment of lead-toxic solid wastes. This innovative treatment technology also offers a great potential for in-situ application to immobilize lead most economically without generation of any wastewater or byproducts.
FIG. 3 illustrates schematically the process of the present invention. The lead-contaminated uncontrolled hazardous waste site 10 with lead-toxic waste is subject to excavation and segregation 20 of waste piles based on their total lead and TCLP lead contents into (a) heavily contaminated pile 30A, (b) moderately contaminated waste pile 30B and (c) least contaminated waste pile 30C. The staged soil and solid waste material in piles 30A, 30B and 30C is subjected to grinding, shredding, mixing 40 and screening 50 through an appropriately sized mesh sieve. The screening yields particles that are usually less than 5 inches in diameter for mixing with gypsum powder 60 in a grizzly that allows a uniform coating of gypsum over the soil particles and waste aggregates during the grinding, shredding and/or mixing step. Alternatively, as shown by the dashed line, gypsum powder 10 may be added continuously to the screened solid waste material in prescribed amounts as determined during treatability trials. Most of the leachable lead binds chemically with gypsum at molecular level to form lead sulfate, which crystallizes into a synthetic nucleus of mixed calcium anglesite and pure anglesite minerals identified in the treated material by chemical microscopy techniques.
The gypsum-coated waste particles and aggregates are the transported on a belt conveyor 70 or other conveying means to an area where an effective amount of phosphoric acid solution 80 of specified strengths in water 90 is added or sprayed just prior to thorough mixing in a pug mill 100 (or other mixing means). The temperature of the phosphoric solution is preferably maintained above 30° F. to prevent it from gelling. The treated soil and wastes are subject to curing 110 and drying 120 on a curing/drying pad, or may less preferably be cured and dried using thermal or mechanical techniques. The end product of the process passes the Paint Filter Test. During the curing time of about four hours, various "super-hard phosphate" mineral species, such as calcium-substituted hydroxy lead-apatites and mixed calcium-lead phosphate-sulfate mineral species, are formed in treated waste media 130. Crystals of these mineral species (in early stages of development) have been identified in the treated soil materials and solid waste by geo-chemical and microscopy techniques like PLM and SEM.
The proportions of waste materials and reagents used in the produce lead sulfate in contaminated solid or solid waste material. In addition, the amount of phosphate-supplying reagent is prescribed in an amount sufficient to produce mineral species such as hydroxy-lead apatite in contaminated soil or solid waste material during a relatively short curing time of 4 hours, usually ranging from about 3 to about 5 hours. Further drying of the treated material may take 24 to 96 hours, but has not been required in any application to date. Table II documents the optimum curing time of 4 hours for the process. In all instances, the leachable lead as measured by the EP Toxicity Test Produce was found below 0.6 mg/l and the differences between analytical values below this level and statistically insignificant.
TABLE II______________________________________Documentation of Optimum Curing TimeUsing EP Toxicity Test criteria for lead fixation EP Toxic EP Toxic Pb Concentration Pb in mg/l found in processedWaste (Untreated sample at a Curing Time ofMatrix Sample) 4 Hrs. 48 Hrs. 96 Hrs.Category mg/l mg/l mg/l mg/l______________________________________Pb Toxic 495 0.4 0.4 0.6Soil APb Toxic 46 0.3 0.2 0.2Soil BPb Toxic 520 0.3 0.5 0.5Soil C______________________________________
The amount of the gypsum powder and the phosphoric acid employed will be dependent on the amount of contaminant present in the soil, initial characteristics of the solid waste material, whether the material is in-situ or is excavated and brought to an off-site facility for treatment; the same is true for other sulfate compounds and phosphate reagents. The following Example I describes various ratios of the chemical reagents for application to the excavated lead-contaminated solid wastes in order to render the leachable lead substantially insoluble; i.e., to reduce the leachable lead to levels below 5.0 mg/l by EP Toxicity Test lead and TCLP Test criteria now in force under current land-ban regulations.
Temperature and Pressure
Ambient temperature and pressure may be used for the disclosed treatment process, permitted the operations of the feeding and mixing equipment allow such. Under sub-freezing conditions, phosphoric acid may be heated to 50° F. to prevent it from gelling and in order to keep it in a pumpable viscosity range.
Treatment System Design
The treatment may be performed under a batch or continuous system of using, for example, a weight-feed belt or platform scale for the metal-hazardous waste materials and a proportionate weight-belt feed system for the dry ingredient or ingredients and powders of at least one of the groups. A metering device, e.g., pump or auger feed system, may instead, or additionally, be used to feed the ingredients of at least one of the groups.
EXAMPLE 1
Single Step Mixing of Treatment Chemicals
A lead contaminated soil from a battery cracking, burning, and recycling abandoned site was obtained and treated with group one and group two chemicals in one single step at bench-scale. The contaminated soil contained total lead in the range of 11.44% to 25.6% and TCLP lead in the range of 1781.3 mg/l to 3440 mg/l. The bulk density of contaminated soil was nearly 1.7 g/ml at moisture content of 10.3%. The contaminated soil pH was 5.1 with an oxidation reduction potential value of 89.8 mV. To each 100 g lot of lead hazardous waste soil, sufficient amounts of group one and group two treatment chemicals and reagents were added as illustrated in Table III, in order to render it non-hazardous by RCRA (Resource Conservation and Recovery Act) definition.
TABLE III______________________________________ TCLP LeadTest Run Treatment Additive(s) (mg/l)______________________________________I 5% lime, 5% gypsum, 10.2% phosphoric 0.5II 12% phosphoric, 10% potassium sulfate 2.2III 12% phosphoric, 10% sodium sulfate 3.5IV 15% TSP 3.7V 12% phosphoric, 10% Portland Cement I 0.2VI 12% phosphoric, 10% Portland Cement II 0.9VII 12% phosphoric, 10% Portland Cement III 0.3VIII 12% phosphoric, 10% gypsum 4.6IX 15% TSP, 10% Portland Cement I 0.1X 15% TSP, 10% Portland Cement II 0.2XI 15% TSP, 10% Portland Cement III 0.2XII 15.1% phosphoric 3.6XIII 10% trisodium phosphate, 10% TSP 1.2XIV 6.8% phosphoric, 4% TSP 4.5XV 10% gypsum 340XVI 12% phosphoric, 5% lime 0.9Control Untreated Check 3236.0______________________________________
It is obvious from TCLP lead analyses of fifteen test runs that the single step mixing of at least one component of either or both group one and group two treatment chemicals is very effective in diminishing the TCLP lead values. In test run I, mixing of lime and gypsum from group one additives and phosphoric from group two decreased the TCLP lead to levels below 1 mg/l from 3440 mg/l with a curing time of less than 5 hours. Although the treatment chemicals of group two are more effective in decreasing the TCLP lead than the treatment chemicals of group one, as illustrated by the comparison of test runs XII and XV for this waste soil, but the combined effect of both groups is even more pronounced in decreasing the leachable lead. Results of these bench-scale studies were confirmed during engineering-scale tests. Single step mixing of 5% lime, 11.76% phosphoric acid and 15% water in a 2000 g hazardous soil diminished the TCLP lead values from 3440 mg/l to 0.77 mg/l in less than 5 hours. Likewise, single step mixing of 300 g Triple Super Phosphate (TSP), 200 g Portland Cement (PC) and 300 ml water in 200 g hazardous soil decreased the TCLP lead to levels below 0.3 mg/l within a relatively short curing time. Single step mixing of both groups of treatment chemicals can dramatically reduce treatment costs making this invention highly attractive and efficient for commercial use.
The first advantage of using lime and phosphoric acid combination over the use of TSP and PC is that in the former a volume decrease of 6% was realized when compared to the original volume of untreated material. In the later case, a volume increase of 37% was measured due to hydration of cement. The second advantage of using phosphoric and lime combination is that the mass increase is less than the mass increase when TSP and PC are added. Quantitatively, the mass increase in this hazardous waste soil treatment was approximately 16.7% due to combination of lime and phosphoric whereas the mass increase was about 40% due addition of TSP and PC. And therefore, those skilled scientists and engineers learning this art from this patent, must make an economic judgement for each lead contaminated process material and waste stream which chemical quantity from each group would be most effective in rendering the treated material non-hazardous.
The third advantage in using lime and phosphoric over the use of TSP and PC is that the former does not change in physical and mechanical properties of original material and if a batch fails for shortage of treatment chemicals, it can be retreated rather easily by adding more of the treatment reagent. The material treated with PC hardens and may form a monolith which is difficult to retreat in case of a batch failure.
EXAMPLE 2
Interchangeability of Two Step Mixing Method
In the lead contaminated soil from the abandoned battery recycling operations, the treatment chemicals of either group can be added first and mixed thoroughly in an amount sufficient to decrease the TCLP lead below the regulatory threshold. Two step mixing method of the group one and group two treatment additives is as effective as single step mixing of same quantity of treatment chemicals selected from group one and group two.
Table IV illustrates data that confirm that the application of group one treatment chemicals in step I is about as effective as application in step II. The same is true for group two treatment chemicals. Thus, the two steps are essentially interchangeable. The reversibility of the steps according to the present invention make it very flexible for optimization during commercial use, scaling up and retreatment of any batches that fail to pass the regulatory threshold criteria.
TABLE IV__________________________________________________________________________Treatment-Additives__________________________________________________________________________ TCLP Total LeadTest Run Step I Step II Lead % mg/l__________________________________________________________________________Two Step Mixing MethodsI 10% gypsum & 2% 12% phosphoric 20.8 1.8 lime (Group I) acid (Group II)II 12% phosphoric 10% gypsum & 2% 24.4 1.9 (Group II) lime (Group I)III 10% gypsum 10.6% phosphoric 24.4 3.4 (Group I) (Group II)IV 10.6% phosphoric 10% gypsum 22.4 3.5 (Group II) (Group I)__________________________________________________________________________Single Step Mixing MethodV 10% gypsum and 12% phosphoric 23.6 3.5Untreated Control/Check 23.1 3440__________________________________________________________________________
EXAMPLE 3
Retreatability and Single Step Mixing
A sample of hazardous cracked battery casings of 1/2"-1" size containing 14% to 25.2% total lead and about 3298 mg/l of TCLP was obtained for several test runs of the invention to verify the retreatability of batches that fail because of the insufficient dose of treatment chemical added. The results of initial treatment and retreatment are presented in Table V and compared with single step mixing treatment additives from both groups. About 200 g of hazardous material was treated with 10.5% phosphoric acid, 2.5% gypsum and 1.25% lime, all mixed in one single step. The TCLP lead was decreased from 3298 mg/l to 2.5 mg/l as a result of single step mixing in test run V (TABLE V).
When the amount of additive from group two was less than the optimum dose needed, the TCLP lead decreased from 3298 mg/l to (i) 1717 mg/l when 4.2% phosphoric and 1% lime were added during step I and II respectively and (ii) 2763 mg/l when 4.2% phosphoric and 5 % gypsum were added, compared to untreated control.
Since the TCLP lead did not pass the regulatory criteria of 5 mg/l, treated material from test run I and II was retreated during test run III and IV, respectively, using sufficient amounts of phosphoric acid (an additive from group two) in sufficient amount to lower the TCLP lead to 2.4 mg/l and 2.5 mg/l, respectively. Furthermore, this example confirms that lime is more effective in decreasing TCLP lead than gypsum among different additives of group one. And as a result, the requirement of group two treatment reagent is lessened by use of lime over gypsum. The example also illustrates that one or more compounds of the same group can be used together to meet the regulatory threshold limit.
TABLE V______________________________________Treatment Additives______________________________________Two Step Mixing Methods TCLP LeadTest Run Step I Step II mg/l______________________________________I 4.2 phosphoric 1% lime 1717II 4.2% phosphoric 5% gypsum 2763Untreated Control 3296______________________________________Retreatment (Single Step Mixing) MethodIII-I 6.8% phosphoric 2.4IV-II 8.5% phosphoric 3.5Single Step MixingV 10.5% phosphoric, 2.5% gypsum, 2.5 1.25% lime______________________________________
EXAMPLE 4
Wide Range of Applications and Process Flexibility in Curing Time, Moisture Content and Treatment Operations
TABLE VI illustrates different types of waste matrix that have been successfully treated employing the one step and two step mixing treatment additives from group one and group two. For these diverse waste types and process materials, total lead ranged from 0.3% to 23.5%. This example discloses the flexibility and dynamics of the treatment process of the invention in rendering nonhazardous, by RCRA definition, a wide range of lead-hazardous and other metal-hazardous materials within a relatively short period of time, usually in less than 5 hours. It is expected that this process will also render bismuth, cadmium, zinc, chromium (III), arsenic (III), aluminum, copper, iron, nickel, selenium, silver and other metals also less leachable in these different types of wastes. The moisture content of the waste matrix is not critical and the invented process works on different process materials and waste types independent of the moisture content. The treatment operations can be carried out at any level--bench, engineering, pilot and full-scale, on relatively small amounts of hazardous waste material in laboratory to large amounts of contaminated process materials, soils, solid wastes, waste waters, sludges, slurries and sediments outdoor on-site. The process is applicable in-situ as well as ex-situ.
TABLE VI__________________________________________________________________________UNIVERSE OF APPLICATION FOR THEINVENTION MAECTITE TREATMENT PROCESS LEACHABE LEAD (MG/L)LEAD CONTAMINATED TREATMENT TOTAL Before After VOLUMEWASTE TYPE ADDITIVE LEAD % Treatment Treatment DECREASE__________________________________________________________________________ %OLD DIRT 3.4% Phosphoric* 2.2 164.4 1.5 16.7WASTE WITH BROKEN 8.1% Lime 2.7 197.5 ND (<.5)BATTERY CASING 1% Gypsum and 3.4% PhosphoricSLAG-LEAD SMELTER 10.2% Phosphoric 6.6 21.3 2.0LEAD-BIRD SHOT 16% Phosphoric 16.1 3720 ND (<.5) 14% Lime and 30% GypsumLEAD-BUCK SHOT 16% Phosphoric 11.4 1705 ND (<.5) 14% Lime and 28% GypsumBATTERY CASINGS 5% Gypsum 12 288 0.6 0ORGANIC HUMUS SOIL 0.5% Lime 1.9 23.2 ND (<.5) 29 2.0% Phosphoric50:50 MIXTURE OF 4% Gypsum .5 687 0.7 3.3CASINGS AND SAND 4% Phosphoric 422.2 0.95 23.6SOLID WASTE SOIL 3% Lime 23.5 12.0 6.0Contaminated With 12% PhosphoricTetrethyl leadSOIL CONTAMINATED 10% Gypsum 4.74 590 3.7WITH LEADED GASOLINE 6% Phosphoric 3% Lime 3.2 213 1.6 5.1% PhosphoricCARBON WITH LEAD DROSS 4.7% Phosphoric 12.6 105.6 0.5WIRE FLUFF 1.7% Phosphoric 0.3 19 0.7WIRE CHIP 0.75% Phosphoric 0.4 28 ND (<.2)LAGOON SEDIMENT 0.6% TSP 0.3 3.9 0.23 0.5% Phosphoric 5.6 0.3SLUDGE-INDUSTRIAL WASTE 2.2 59.3 1.6RCRA ORGANIC SLUDGE 0.6% Phosphoric 9.4 580 ND (<.5) 10% GypsumFILTER CAKE 8.5% Phosphoric 2.9 245.3 1.1GRAVEL 5% Gypsum 0.16 7.5 0.5 2.2% PhosphoricROAD GRAVEL 10% Gypsum 0.34 46 ND (<.5) 8.4% PhosphoricMIXTURE OF BATTERY 2.5% GypsumCASINGS (SOLID WASTE) 3.4% Phosphoric 1.3 75 0.6 19.6AND SOILINDUSTRIAL WASTE 1 g Lime 2.75 91 0.7(B) 3.4% PhosphoricINDUSTRIAL PROCESS 3.4% Phosphoric 1.3 61 ND (<.5)MAT. (G)SOIL (B) 3.4% Phosphoric 4.1 129.5 0.6 25.6SOIL (S) 50% Gypsum 11 <0.01SOIL (O) 1.3% Phosphoric 0.38 34.6 ND (<.5)SOIL (C) 5% Lime 11.78 130.6 0.33 8.5% PhosphoricBATTERY CASINGS 5% Gypsum 2.5 110.1 1.9 3.4% PhosphoricGRAY CLAY SOIL 5% Trisodium 2.2 46.6 0.2 Phosphate__________________________________________________________________________
EXAMPLE 5
Nearly twenty (20) different chemicals and products from various vendors and supply houses were screened for chemical fixation of leachable lead in hazardous solid waste samples. Only six (6) of these treatments chemicals were found effective in decreasing the leachable lead as measured by: (1) the EP Toxicity Test and (2) the TCLP Test. Table VII presents a summary of leachable lead found in untreated and treated waste samples allowed to cure for a minimum of 4 hours after treatment with at least one of the effective chemicals. Treatment chemicals found relatively ineffective for lead fixation included a variety of proprietary products from American Colloid Company and Oil Dri, different sesquioxides like alumina and silica, calcium silicate, sodium silicate, Portland cement, lime, and alum from different vendors. Results for these ineffective chemicals are not shown in Table VII.
TABLE VII______________________________________Relative effectiveness of varioustreatment chemicals screened todecharacterize the lead-toxic solid wastes Leachable Lead in mg/l EP Toxicity TCLPTreatment Chemical (Step) Test Test______________________________________I. Untreated Control 221.4 704.5II. Single Treatment Chemical(One Step Treatment)a. Sulfuric Acid (I) 11.7 39.8b. Phosphoric Acid (I) 1.0 5.9c. Superphosphate Granular (I) 2.7 11.4d. Liquid Phosphate Fertilizer (I) 19.4 64.3e. Gypsum Powder (I) 24.9 81.8f. Sodium Phosphate (I) 28.7 93.9III. Two Step Treatmentg. Sulfuric (I) & Lime (II) 20.6 68.1h. Gypsum Powder (I) & Alum (II) 3.9 15.3i. Sodium Phosphate (I) & 3.1 12.6Phosphoric (II)j. Gypsum (I) & Phosphoric (II) N.D.* 1.6IV. Three Step Treatmentk. Gypsum (I), Alum (II) & 12.8 43.3Sodium Phosphate (III)l. Gypsum (I), Phosphoric (II) & N.D.* 1.4Sodium Phosphate (III)______________________________________ *N.D. means nondetectable at <0.50 mg/l.
Evaluation of a single treatment chemical in one step reveals that phosphoric acid was most effective in fixation of leachable lead followed by granular super-phosphate, a fertilizer grade product available in nurseries and farm supply houses. However, neither treatment effectively treated leachable lead to the USEPA treatment standard of 5.0 mg/l by TCLP methodology.
Although both phosphoric acid and granular superphosphate were effective in meeting the now obsolete EP Toxicity Test criteria at 5.0 mg/l, this test has been replaced by TCLP Test criteria for lead of 5.0 mg/l. Single application of the phosphoric acid, granular superphosphate or any other chemical was short of meeting the regulatory threshold of 5.0 mg/l by TCLP Test criteria for lead.
In a two-step treatment process, application of gypsum during Step I and treatment with phosphoric acid in Step II resulted in decrease of TCLP-lead consistently and repeatedly below the regulatory threshold of 5.0 mg/l. The results of this two-step treatment process utilizing gypsum in Step I and phosphoric acid in Step II are most reliable and hence, the two-step process may be applied to a wide variety of lead contaminated wastes as exhibited in Example II.
A three-step process, as set forth in Table VII, was not perceived to be as economically viable as a two-step treatment process, despite its ability to reduce lead levels in satisfaction of the TCLP Test criteria. A process that employees the beneficial combination of treatment first with a sulfate compound and then with a phosphate reagent in accord with the present invention, in combination with one or more additional treatment steps, may nevertheless be within the scope of the invention.
In order to illustrate the relative proportions of two chemicals, e.g., gypsum and phosphoric acid, needed for treatment of lead-toxic wastes, three soil samples from a lead contaminated test site were processed using the present invention, in which gypsum powder was used in the first step, and phosphoric acid solution in water at concentrations of about 7, 15 and 22 percent by weight in the second step. The soil was measured for lead content in accordance with the EP Toxicity Test before and after treatment. A level of leachable lead below 5 mg/l was considered non-hazardous according to this procedure. During these test runs, the EP Toxicity Test criteria were in force for treated waste material. The results of these tests are set forth in Table VIII:
TABLE VIII______________________________________Effectiveness in Fixation and Stabilization ofLeachable Lead in Lead Toxic Soils EP TOXIC LEAD TEST RESULTS PROCESS STEPS Before AfterSoil Sample Gypsum Phosphoric Treat- Treat-(Lead-toxic Step I Step II ment mentwaste) (g/kg soil) (g/kg soil) mg/l mg/l______________________________________1. Low lead 20 10 8 <0.1 contamination2. Moderate 30 20 61 <0.1 contamination3. High lead 40 30 3,659 1.7 contamination______________________________________
The foregoing results demonstrate that the process of the present invention was effective in all three samples, representing 3 different levels of lead contamination. The process is flexible and is usually optimized during bench scale treatability studies for each waste type to immobilize the leachable lead and to decharacterize or transform the lead-toxic waste into non-toxic solid waste acceptable to TSD facilities under current land ban regulations. A net reduction of 36.4% in waste volume through use of the instant process has been observed. Typical volume reductions are set forth in Table IX.
TABLE IX______________________________________Changes in Solid Waste Volumeas a Result of Treatment with the Two-Step Process SOLID WASTE VOLUME Initial Final (AfterSOLID WASTE (Before Application Decrease inMATERIAL Application of Process Waste(Treatment Scale) of Process) and Curing) Volume (%)______________________________________1. Low toxic soil 3850 cu. yd. 2450 cu. yd. 36.4 (full scale)2. Lead-toxic Solid Waste (Bench Scale) Test Run I 106.1 cu. in. 81.51 cu. in. 23.0 Test Run II 22.0 cu. in. 17.3 cu. in. 21.4______________________________________
The most profound effect of the process of the present invention is at a structural level, where the break-down of granular aggregates is associated with a loss of fluffiness and a decrease in pore space and increased compaction due to physical, mechanical and chemical forces at different levels. At a molecular level, phosphoric acid breaks down the minerals containing carbonates and bicarbonates, including cerussites, in stoichiometric proportions. Soon after the addition of phosphoric acid to a solid waste containing cerussites, extensive effervescence and frothing becomes evident for several minutes and sometimes for a few hours. The phosphoric acid breaks down the acid sensitive carbonates and bicarbonates leading to the formation of carbon dioxide, water and highly stable and insoluble sulfate and phosphate mineral compounds. Thus, structural changes due to interlattice reorganization as well as interstitial rearrangement in waste during processing are associated with an overall decrease in waste volume. Depending on the extent of carbon dioxide loss from the breakdown of carbonates and bicarbonates present in the lead-toxic solid waste, the process may lead to a slight loss of waste mass as well. Water generated during the chemical reactions is lost by evaporation, which further decreases the mass and volume of the treated solid wastes and soils.
The cost of the process of the present invention is moderate to low, depending upon (i) waste characteristics, (ii) treatment system sizing, (iii) site access, (iv) internment of final disposition of treated material and (v) site support requirements. The costs of treatment and disposal are presently on the order of $115 per ton of lead-toxic waste, as compared to off-site conventional treatment and disposal costs of over $250 per ton if no treatment in accord with the invention had been performed. Moreover, recent land ban regulations would prohibit the disposal of all lead-toxic wastes in landfills. The foregoing Example makes clear that the process of the present invention provides an efficient technology that is economically attractive and commercially viable in meeting regulatory criteria for landfills.
EXAMPLE 6
The process of the present invention was applied on bench scale to five different lead-toxic waste materials that were characterized for total lead, TCLP-lead, moisture content and pH before and after treatment. A curing time of 5 hours was allowed for completion of the treatment process. The results compiled in Table X exhibit the profound effects of the process in decreasing the TCLP lead in a wide range of lead-toxic soils and solid wastes containing total lead as high as 39,680 mg/kg and TCLP lead as high as 542 mg/l. In each of the five cases, the instant process immobilizes the leachable lead to levels below the regulatory threshold of 5 mg/l set by the TCLP Test criteria for lead currently in force under the land ban regulations of the United States Environmental Protection Agency.
TABLE X______________________________________Typical changes in solid waste characteristicsdue to process effects MEASURED VALUES AfterSOLID WASTE Before Treatment &HARACTERISTICS Treatment Curing______________________________________I. Lead-toxic SW-A Total lead, % 1.442 1.314 TCLP-Lead, mg/l 542.0 2.0 Moisture, % 23.0 33.0 pH, S.U.II. Lead-toxic SW-B Total lead, % 0.847 0.838 TLCP-Lead, mg/l 192.0 2.4 Moisture, % 27 36 pH, S.U.III. Lead-toxic SW-C Total lead, % 3.968 3.066 TLCP-Lead, mg/l 257.6 1.0 Moisture, % 10.0 18.1 pH, S.U. 7.2 4.5IV. Lead-toxic SW-D Total lead, % 2.862 2.862 TLCP-Lead, mg/l 245.3 0.38 Moisture, % 71.6 84.1 pH, S.U. 8.1 6.3V. Lead-toxic SW-E Total lead, % 0.16 0.12 TLCP-Lead, mg/l 7.5 1.87 Moisture, % 12.3 23.0 pH, S.U. 7.0 5.4______________________________________
It is obvious from Table X that the instant process operates over a wide range of moisture and pH conditions. It is associated with 8 to 11% rise in moisture content. The end product of the treatment process may contain moisture in a typical range of 18% to 36% on a dry weight basis. The end product passes the Paint Filter Test for solids and there are not other byproducts or side streams generated during the process. The treated solid waste is cured in 4 to 5 hours and may be allowed to dry for 2 to 3 days after treatment for loss of unwanted moisture prior to final internment and disposition. This time is sufficient for the TCLP Tests to be completed as part of the disposal analysis under land ban regulations enforced by the USEPA.
It is necessary to establish the quantities of gypsum and phosphate reagent on a case-by-case basis, because the consumption of these materials will depend not only upon the initial lead level in the waste or soil, but also upon other waste characteristics such as cation exchange capacity, total buffering capacity, and the amounts of carbonates and bicarbonates present, among others. Bench scale treatability studies for each solid waste considered will be necessary to determine the optimum levels of the materials that are employed. The treatability studies are designed to optimize the amount and grade of gypsum powder (or other sulfate compound) needed during step I, and the amount and concentration of phosphoric acid (or other phosphate compound) needed in step II for cost-effective operation of the treatment system. Those skilled in the art are knowledgeable of such bench studies, which are usually carried out as precursors to full scale treatment.
Although the present invention has been described in connection with preferred embodiments, it will be appreciated by those skilled in the art that additions, modifications, substitutions and deletions not specifically described may be made without departing from the spirit and scope of the invention defined in the appended claims. | The present invention discloses a method of treating lead bearing process materials and lead toxic hazardous wastes. The invention relates to treatment methods employed to chemically convert leachable lead in lead bearing solid and liquid waste materials to a non-leachable form by mixing the material with lime, gypsum and/or phosphoric acid. The solid and liquid waste materials include contaminated sludges, slurries, soils, wastewaters, spent carbon, sand, wire chips, plastic fluff, cracked battery casings, bird and buck shots and tetraethyl lead contaminated organic peat and muck. The present invention discloses a process comprising a single step mixing of one or more treatment additives, and a process comprising a two step mixing wherein the sequence of performing the steps may be reversible. The present invention provides a new way of treating a universe of lead contaminated materials at any pH. | 6 |
BACKGROUND OF THE INVENTION
The present invention relates to a process for making polycrystalline cubic boron nitride (CBN). The manufacture of CBN by a high pressure/high temperature technique is known in the art and is typified by the process described in U.S. Pat. No. 2,947,617 of Wentorf, a basic monocrystalline CBN case. U.S. Pat. No. 4,188,194 describes a process for making sintered polycrystalline CBN compacts which utilizes pyrolytic hexagonal boron nitride (PBN) in the absence of any catalyst. A compact is a mass of abrasive particles bonded together in a self-bonded relationship (see U.S. Pat. Nos. 3,852,078 and 3,876,751); by means of a bonding medium (see U.S. Pat. Nos. 3,136,615, 3,233,988, 3,743,489, 3,767,371, and 3,918,931); or by means of combinations thereof. U.S. Pat. No. 3,918,219 teaches the catalytic conversion of hexagonal boron nitride (HBN) to CBN in contact with a carbide mass to form a composite body. A CBN compact is comprised of a plurality of CBN crystals suitably bonded together to form a large, integral, tough, coherent, high-strength mass. Compacts may be used in applications such as, for example, machining, dressing, and drilling (see U.S. Pat. Nos. 3,136,615 and 3,233,988).
Boron-rich polycrystalline CBN as used in the subject invention can be prepared by high pressure/high temperature processing of mixtures of HBN powder and either elemental boron or various boron containing compounds (e.g. AlB 12 ), as described in British Pat. No. 1,513,990; or using vacuum-fired HBN powder to produce excess surface elemental boron which then is converted to CBN as described in U.S. Pat. No. 4,289,503. In these processes, the large chunks of polycrystalline CBN which are produced typically are milled to a size suitable for use in various grinding or other applications. In the milling process, a portion of the material normally is crushed too fine or has an undesirable shape for use in grinding applications and, thus, some use for such unwanted material is desirable. Also, current commercial polycrystalline CBN compacts could be improved by increased edge strength and decreased brittleness (lack of impact strength). An improved polycrystalline CBN product is desired.
BROAD STATEMENT OF THE INVENTION
The present invention provides improved sintered boron-rich polycrystalline CBN compacts of improved edge strength and impact strength. It also provides a method for utilization of the milling by-products obtained when milling boron-rich polycrystalline CBN. The method for making the sintered polycrystalline CBN compact comprises placing sintered boron-rich polycrystalline CBN particles in a high temperature/high pressure apparatus and subjecting said boron-rich CBN particles to a pressure and a temperature adequate to re-sinter the CBN particles, the temperature being below the reconversion temperature of CBN to HBN, for a time sufficient to re-sinter the polycrystalline CBN particles therein. The combination of pressure and temperature is in the CBN stable region of the phase diagram for boron nitride. The temperature then is reduced sufficiently to inhibit reconversion of CBN to HBN (typically 1000° or less) followed by reduction of the pressure and recovery of the re-sintered polycrystalline CBN compact. The process unexpectedly is conducted in the absence of catalysts. Other material (sintering inhibiting impurities) which might interfere with or inhibit the sintering of boron-rich polycrystalline CBN particles also should be avoided. In addition a support material such as a cemented metal carbide may be placed adjacent the boron-rich CBN particles in the high pressure/high temperature apparatus so as to form in-situ a supported polycrystalline CBN compact. The desired pressure is between about 45 and 80 Kbars and the preferred temperature ranges from about 1500°-2300° C., but below the CBN reconversion temperature. The reconversion (or back conversion) temperature is defined to be that temperature at which boron nitride reconverts from the cubic crystal structure to the hexagonal. This temperature is found along the equilibrium line separating the hexagonal boron nitride stable region from the cubic boron nitride stable region in the phase diagram for boron nitride (see U.S. Pat. No. 3,212,852; FIG. 6 and col. 8, line 66-col. 9, line 42).
Advantages of the present invention include the ability to make exceedingly tough, impact resistant bodies with improved edge strength. Another advantage is the production of such bodies without the addition of sintering aids. A further advantage is the beneficial utilization of a conventional milling by-product to make valuable CBN compacts. These and other advantages will be readily apparent to those skilled in the art based upon the disclosure contained herein.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1-4 illustrate, in cross-section, various configurations for reaction zone assemblies (or cells) for use within a high pressure/high temperature apparatus such as those described in U.S. Pat. Nos. 2,947,611, 2,941,241 and 2,941,248.
The drawings will be described in detail below.
DETAILED DESCRIPTION OF THE INVENTION
The boron-rich polycrystalline CBN particles used in making the sintered polycrystalline CBN compact of the present invention may be made by any suitable technique known in the art. One technique for preparation of the boron-rich polycrystalline CBN involves the high pressure/high temperature processing of mixtures of hexagonal boron nitride (HBN) powder and either elemental boron or various boron containing compounds (e.g. AlB 12 ) as described in British Pat. No. 1,513,990. Another process for making the boron-rich polycrystalline CBN involves generating excess boron on the surfaces of oxide-free HBN prior to its conversion to cubic boron nitride. The excess boron is generated by a pre-treatment which is carried out at a temperature in the hexagonal boron nitride thermal decomposition range by vacuum firing and heating under an inert atmosphere followed by conversion to CBN by high pressure/high temperature processing as described in U.S. Pat. No. 4,289,503. Regardless of the process employed, boron-rich polycrystalline CBN generally is produced in large chunks which typically are milled to particle sizes more suitable for use in various grinding or other applications. A distinct advantage of the present invention is the ability to advantageously utilize the milling by-product resulting from such size milling operations. While the sintered polycrystalline CBN compact of the present invention may utilize advantageously such milling by-products or fines, the process also operates quite effectively on larger sized boron-rich CBN particles ranging in size up to 250 microns (60 mesh) or greater. In this regard, the size of the boron-rich polycrystalline CBN particles may be the same as the size of conventional CBN particles being subjected to a high pressure/high temperature operation for formation of conventional polycrystalline compacts, such as described in U.S. Pat. No. 3,767,371.
Another advantage of the present invention is the ability to beneficially utilize the CBN produced, for example, by the process of U.S. Pat. No. 4,289,503 which is microcrystalline in nature. The use of any size particles of this microcrystalline CBN to make CBN compacts results in a finer microstructure of the CBN compact with improved toughness over coarser grained compacts. Such fine grained structures are difficult to manufacture by conventional processes. However, the finer microstructure CBN compact of the present invention is easier to make than with conventional processes because fine separate particles of single crystal CBN do not have to be handled separately.
It will be appreciated that boron-rich polycrystalline CBN particles already are "sintered" in their formation so that the process of the present invention may be termed as a "re-sintering" process. Of significant departure from the art is the quite unexpected discovery that the sintered boron-rich polycrystalline CBN particles could be re-sintered for the formation of strong, coherent compacts. Conventional sized crystal cubic boron nitride particles often are formed into sintered polycrystalline compacts utilizing a catalyst such as described in U.S. Pat. No. 2,947,617 or other means for achieving bonding. The present invention, however, results unexpectedly in the formation of superior polycrystalline CBN compacts by re-sintering the boron-rich polycrystalline CBN particles without the aid of a catalyst at temperature and pressure conditions of the order typically employed in processes which utilize a catalyst.
In practicing the present invention, the boron-rich CBN particles are placed in a high pressure/high temperature apparatus such as described in U.S. Pat. No. 4,289,503 and placed under pressure and then temperature for a time sufficient for re-sintering to occur. The sample then is allowed to cool under pressure as known in the art to inhibit reconversion or back conversion of CBN to HBN and finally the pressure is decreased to atmospheric pressure, and the mass of re-sintered polycrystalline CBN recovered. The reaction zone assemblies or cells of FIGS. 1-4 have been used in the making of sintered polycrystalline CBN compacts in accordance with teachings of the present invention. The reaction zone assemblies or cells of the drawings include pyrophyllite cylinder bushing 10 which alternatively may be made of glass, soft ceramic, talc, alkali halide, steatite or forms of soapstones. Positioned concentrically within and adjacent bushing 10 is graphite resistance heater tube 12. Metal foil wrap 30 (FIGS. 2-4) may be inserted optionally between bushing 10 and graphite tube 12 as a contamination shield. The shield metal is a refractory metal which may be selected from the group consisting of zirconium, titanium, tantalum, tungsten, and molybdenum.
Concentric refractory metal tube 14 (FIG. 1) is retained within graphite tube 12 and may be formed from the refractory metal listed above. Intact cylinders more commonly are obtained with the graphite tube-lined cell assemblies (FIGS. 2-4) whereas fractured and broken samples are obtained with the refractory metal, e.g. titanium, tube construction shown in FIG. 1. The assemblies in FIGS. 1 and 2 have sample 16 of boron-rich polycrystalline CBN particles placed within the cylindrical housing assemblage with the ends containing graphite plugs 18 adjacent sample 16 with pressure-transmitting plugs placed outside of graphite plugs 18. Hot pressed hexagonal boron nitride plugs may be used as plugs 20 in conventional fashion.
In FIG. 3, graphite plugs 40 are placed adjacent the sample and between sample 16 and graphite plugs 18. In FIG. 4, a plurality of samples may be made in a single cell assembly having graphite disk 52 placed between the samples. Additional embodiments of the reaction cell may find utility and certainly are included within the scope of the present invention. Further details on high pressure/high temperature reaction cells may be found in U.S. Pat. Nos. 3,767,371, 4,188,194, and 4,289,503.
Preferably, the boron-rich polycrystalline CBN particles placed within the reaction cell should contain no catalyst material nor any other material which is a contaminant or which hinders the CBN sintering process, i.e. no CBN sintering inhibiting impurities. Besides the boron-rich polycrystalline CBN particles, additional boron containing compounds (e.g. AlB 12 ) or the like may be included as a source of boron in the cell, for example as taught in British Pat. No. 1,513,990, cited above. In any event, the sample is subjected to a pressure in excess of about 45 Kbars and generally such pressure should range from between about 45 and 80 Kbars. The temperature should be at least about 1500° C., but should be less than the CBN reconversion temperature. Preferably, the temperature should range from about 1500° and 2300° C. The time necessary for the re-sintering to occur necessarily depends upon the temperature and pressure combination chosen as is well known in the art. The Examples will elaborate further on the reaction conditions under which the novel re-sintered polycrystalline CBN compact is made.
It should be understood that the preferred temperatures and pressures specified herein are estimates only in accordance with the high-pressure art which recognizes such variances due to the difficulty in precisely measuring the high pressures and temperatures encountered in this field. Of importance in the process of the present innvention is that conditions of pressure and temperature adequate for CBN sintering (and inadequate for CBN reconversion) are maintained for a time adequate for CBN re-sintering to occur.
The re-sintered polycrystalline CBN compact may be subjected to milling or size attrition for the production of unusually tough and useful CBN particles which may be used in making resin bonded grinding wheels, metal bonded grinding wheels, metal bonded saw elements, and like conventional cutting and abrading tools. Additionally, intact polycrystalline compacts may be cleaned to remove any adhering carbon, titanium, or other material. After cleaning, the samples can be milled to sizes required for grinding applications or the disk and cylinder shaped pieces may be shaped for cutting tool applications. In this regard, the compacts may be used in unsupported or in conventional supported form utilizing a tungsten carbide or other support. While adherence of the polycrystalline CBN compact to the support may be achieved in situ by placing the support material adjacent the boron rich CBN particles prior to formation of the compact in the high pressure/high temperature cell, the joining may also be achieved via brazing or other technique after formation of the sintered polycrystalline CBN compact.
The following Examples show how the invention may be practiced but should not be construed as limiting in any way. In this application, all percentages and proportions are by weight and all units are in the metric system, unless otherwise expressly indicated. Also, all citations referred to herein are incorporated expressly by reference.
EXAMPLES
EXAMPLE 1
Finer than 170 mesh (88 microns) powder was obtained by milling boron-rich polycrystalline CBN prepared in accordance with U.S. Pat. No. 4,289,503. Each re-sintering run utilized 5 gram samples of the milled powder which had been cleaned in accordance with the cleaning procedures in U.S. Pat. No. 4,289,503 and which then was placed in a reaction cell of the configuration depicted in FIG. 2. This cleaning procedure was used with the CBN material in all of the examples. The sintering conditions included a pressure estimated at 67 Kbar and about 2,000° C. for eight minutes. The sintered masses were recovered from the reaction cells, cleaned in hot 10% nitric/90% sulfuric acid to remove any adhering graphite and milled to a particle size of less than 60 mesh (250 microns). After milling, the 60/80 mesh size fraction (88-250 microns) was cleaned in an ultrasonic water bath, rinsed in acetone, air-dried, and coated with 60% by weight of a nickel phosphate coating for use in wheel tests for the dry grinding of M-4 hardened tool steel.
Phenolic resin bonded grinding wheels were prepared to contain 75 weight percent (38.6 volume percent) of the re-sintered CBN abrasive. The grinding wheels were standard 11V9 test wheels, 9.525 cm×3.81 cm×3.175 cm (3.75 in.×1.5 in.×1.25 in.), with a 0.3175 cm (0.125 in.) wide abrasive rim. The wheels were mounted on the grinder and trued using a truing brake and silicon carbide wheel until 0.2-0.3 mm (0.008-0.012 in) of wheel was removed. The wheel was dressed open then with a 220 grit, "G" hardness aluminum oxide stick. Data collected included the volume of wheel consumed, volume of material removed, power and surface finish. The grinding ratio was calculated for each test condition in conventional fashion. The dry grinding tests were conducted under the following conditions:
______________________________________Wheel Speed: 20 meters/second(4,000 SPFM)Table Speed: 2.44 meters/minute(8 FPM)Material: M-2, Rc 60-62 6.4 mm (0.250 inches) × 203 mm (8 inches) 8 piecesInfeed: 0.050 mm (0.002 inches)Material Removal 0.79 cm.sup.3 /minutes(0.048 inches.sup.3 /minutes)Rate:______________________________________
Beside the novel re-sintered CBN abrasive of the present invention, comparative tests were utilized with boron-rich polycrystalline CBN powder as prepared in accordance with U.S. Pat. No. 4,289,503 and with a conventional commercially-available cubic boron nitride abrasive grain. The following data was recorded:
TABLE 1______________________________________ No. Wheels/ Grinding.sup.(1) Grinding.sup.(2)Test No. CBN-type Test Ratio Energy______________________________________26052 Novel Resiniered 3 127 14.626053 Novel Resintered 4 112 18.326050 U.S. Pat. No. 4 120 13.2 4,289,50326051 U.S. Pat. No. 5 101 15.9 4,289,50326054 Conventional 5 78 14.426055 Conventional 4 80 14.3______________________________________ ##STR1## .sup.(2) Grinding energy is watthour/cm.sup.3 of material removed
Based upon above-tabulated data, the following relative grinding ratios were calculated based upon a grinding ratio of 1.0 for the Conventional CBN grinding wheels.
TABLE 2______________________________________RELATIVE GRINDING RATIOSCBN-Type Relative GR______________________________________Conventional 1.00U.S. Pat. No. 4,289,503 1.39Novel Resintered 1.51______________________________________
Thus, it will be seen that the novel re-sintered CBN abrasive of the present invention unexpectedly, though quite convincingly, provides much improved grinding performance compared to the boron-rich CBN from which it was made (U.S. Pat. No. 4,289,503) and compared to conventional commercial CBN powder. Thus, the novel re-sintered CBN powder of the present invention possesses the ability to realize improved grinding ratios compared to CBN abrasive that has heretofore been available.
EXAMPLE 2
A series of high pressure/high temperature sintering tests were conducted on finer than 270 mesh (53 microns) boron-rich polycrystalline CBN aggregate material at various pressure and temperature conditions. The CBN material was obtained by repeated crushing of boron-rich polycrystalline CBN aggregate chunks prepared as described in U.S. Pat. No. 4,289,503. The sample contained particles ranging in size from 270 mesh (53 microns) to dust.
Each test was conducted using 7 gram loads of the powdered CBN in a high pressure cell having the configuration depicted in FIG. 1. The cells were loaded by first inserting the graphite and hot-pressed boron nitride disk shaped plugs in one end of the titanium tube. The sample powder then was poured into the tube and capped with graphite and hot pressed boron nitride plugs. After assembly, the cells were placed in a high pressure belt apparatus and the pressure increased to the level shown in Table 3. After reaching the desired pressure, each sample was heated by passing electrical current through the cell in conventional fashion. After heating, the sample was allowed to cool at pressure for one minute before the pressure was reduced.
The total heating time in each case was 7 minutes. No direct pressure or temperature calibration was conducted for this series of runs, thus the pressure and temperatures set forth below are estimates.
TABLE 3______________________________________ Pressure TemperatureRun No. (Kbar) (°C.)______________________________________1 72 20502 72 20003 72 19254 69 20005 68 20006 67 20007 62 18008 62 17009 62 1200______________________________________
In Runs 1-8, the samples were recovered in the form of predominantly large black sintered pieces ranging in size up to 0.6 cm (0.25 in.) thick by about 1.3 cm (about 0.5 in.) diameter disk. Each of the recovered re-sintered samples of Runs 1-8 would readily scratch conventional CBN polycrystalline compacts. The disk recovered from Run 9, however, was noticeably lighter in color and failed to scratch the polycrystalline CBN compacts. It is postulated that the temperature utilized in Run 9 was too low to effect a level of re-sintering desirable for many commercial applications.
EXAMPLE 3
In these runs, one gram samples of the same boron-rich CBN powder used in Example 2 were pressed in cells having a configuration as in FIG. 3. A total heating time of 7 minutes was used along with the estimated pressure and temperature conditions set forth below.
TABLE 4______________________________________ Pressure TemperatureRun No. (Kbar) (°C.)______________________________________10 58 200011 58 177512 58 160013 58 145014 58 1275______________________________________
In all of the above runs, large unitary pieces, referred to as compacts, were obtained. The compacts from Runs 10-12 would scratch conventional polycrystalline CBN compacts, while the compacts recovered from Runs 13 and 14 would not. Using the scratching ability of the re-sintered compacts against conventional polycrystalline CBN compacts as a desirable sintering criteria benchmark, the above-tabulated results indicate that well-sintered masses are obtained at combined pressures down to at least 58 Kbar and at estimated temperatures of 1600° C. and higher (up to the CBN reconversion temperature).
EXAMPLE 4
Seven grams of the same boron-rich CBN powder as used in the above examples was loaded in a cell having a configuration of FIG. 2 and pressed at about 67 Kbar and 1800° C. for ten minutes. A sintered unitary cylindrical-shaped mass 0.6 inches (1.524 cm) long by 0.52-0.54 inch (1.32-1.37 cm) diameter was obtained. This sample could not be broken by repeated blows with a steel hammer.
EXAMPLE 5
Additional polycrystalline CBN compacts were made in multiple sample cells at press conditions varying over the range of about 59 Kbar to about 45 Kbar and about 1500° to 1900° C. for five minutes. The cell construction for these additional runs was similar to the cell configuration of FIG. 2 except that the two-piece graphite plug (18)/hot pressed BN end plugs (20) were replaced by a single graphite plug. Additionally, discs (0.381 mm or 0.15 in.) of graphite were placed between the samples and the graphite end plugs. The cells were loaded with either two or three individual 2 gram samples separated by the oriented graphite disk. The sample boron-rich polycrystalline CBN material used for re-sintering into compact form was -270 mesh (-53 microns) tailings which had been generated by milling boron-rich polycrystalline CBN compacts made in accordance with U.S. Pat. No. 4,289,503. The sample material had been acid cleaned (HNO 3 /HF) to remove metallic and stone impurities prior to placement within the cell.
Some of the sample material placed in the cells were mixed with 10% by weight AlB 12 powder and with 25% by weight vacuum-fired HBN powder. A number of the compacts made were surface ground flat and cylindrically ground to 1.27 cm (0.5 in.) diameter disk for abrasive resistance testing. These compacts were chosen for evaluating the AlB 12 additive because the re-sintering conditions (pressure and temperature) for them were about the same as the re-sintering conditions used where no additive was present. The abrasive resistance test consisted of turning a silica-filled hard rubber workpiece for a set time period. The relative performance of the compacts to abrasive wear was determined from the amount of wear experienced by each individual compact. From the measured compact wear, an abrasive resistance factor (ARF factor) was calculated according to the following equation:
ARF=t/100×W
where:
t=test time (minutes)
W=compact or tool wear (inches).
The following results were obtained:
TABLE 5______________________________________ Compact Wear Pressure Temp.Sample No. (mils) ARF Additive (Kbar) (°C.)______________________________________Commercial 13 12.3 -- -- --CBN Compact4 14 11.4 10% AlB.sub.12 56 17002 11 14.5 10% AlB.sub.12 60 17003B 10 18.0 None 60 17003A 9 17.7 None 60 1700______________________________________
The above-tabulated results indicate that superior abrasive resistance performance was observed compared to a commercial tungsten carbide supported CBN compact with the re-sintered compacts (Samples Nos. 3A and 3B). Superior abrasive resistance performance also was observed by Sample #2 which contained additive AlB 12 .
Additional compact samples were utilized in turning a hardened steel workpiece (type D2 steel). This set of tests used 0.95 cm (0.375 in.) square compact inserts. The hardened steel workpiece was turned or cut by each sample until 0.381 mm (0.015 in.) wear of the compact was measured. The time in minutes to reach the indicated wear distance was recorded as follows.
TABLE 6______________________________________ Tool Life Pressure Temp.Sample No. (min.) Additive (Kbar) (°C.)______________________________________Commercial CBN 10.4 -- -- --Compact4 11.2 10% AlB.sub.12 56 17002 12.9 10% AlB.sub.12 60 17003A 18.9 None 60 170010 20.7 None 54 1700______________________________________
These results indicate improved performance of the re-sintered boron-rich polycrystalline CBN compacts again in the grinding of hardened steel workpieces. Improved performance additionally was observed when AlB 12 additive was included in the sample powder pressed to make the compacts of the present invention.
EXAMPLE 6
A number of re-sintered boron-rich polycrystalline CBN compacts were made in the cell as configured in FIG. 4 (some samples with and some without optional tantalum foil wrap 30). Sample amounts were 3 grams each and multiple 2 or 3 sample loads (2.8 grams and 2.0 grams samples, respectively) were used at various press conditions set forth below (about 5 minutes at the indicated pressure and temperature).
The compacts made were ground flat to an outside diameter of 0.88 cm (0.347 in.) for abrasive resistance testing. The ARF factor was calculated in accordance with the formula described in Example 6. The following results were recorded. The temperatures were estimated but are thought to be reasonably accurate.
TABLE 7______________________________________ Pressing Conditions Pressure Temp. Compact WearSample No. (Kbar) (°C.) (mils) ARF______________________________________Commercial CBN -- -- 13.0 12.3Compact5 45 1500 9.5 16.86 45 1500 9.5 16.81 60 1800 9.0 17.72(End Compact) 60 1800 9.0 17.72(Center Compact) 60 1800 9.0 17.73 52 1500 9.0 17.74 49 1700 8.5 18.7______________________________________
The above-tabulated results again demonstrate the improved abrasive resistance performance which is obtained utilizing the novel re-sintered boron-rich polycrystalline CBN compacts of the present invention. Such improved abrasive resistance performance was observed over a broad range of pressing conditions as reported above.
EXAMPLE 7
A series of high pressure sintering runs were made on samples in which cemented tungsten carbide discs were placed adjacent to the boron rich polycrystalline CBN powder in the high pressure cells. Re-sintering conditions were estimated to comprise a pressure of about 50-60 Kbar and a temperature of about 1500° C. A number of intact samples were obtained with the sintered boron nitride layer in situ bonded to the tungsten carbide disc. One such sample was ground flat and OD ground to 0.347 in. diameter for abrasive resistance testing. The boron rich polycrystalline CBN powder used in preparing was the same as that used in Example 5. The sample was abrasion resistance tested as described in Example 5 giving an abrasive resistance factor of 15.0 compared to an abrasion resistance factor of 12.3 for the commercial WC supported CBN compacts tested in Examples 5 and 6. | Disclosed is a method for making re-sintered polycrystalline CBN compact which comprises placing sintered boron-rich polycrystalline CBN particles in a high temperature/high pressure apparatus and subjecting said boron-rich CBN particles to a pressure and a temperature adequate to re-sinter said particles, the temperature being below the reconversion temperature of CBN, for a time sufficient to re-sinter the polycrystalline CBN particles therein. The boron-rich polycrystalline CBN particles in the HP/HT apparatus contain no impurity which would interfere with the sintering process (CBN sintering inhibiting impurities) and no sintering aid material. | 2 |
FIELD OF THE INVENTION
[0001] The present invention relates to inserter mechanisms for insertion of a drug delivery device through the skin of a user, and most preferably, for insertion of a flexible cannula which is then left in place for a period of time for continuous or intermittent delivery of a drug into the body. It will be appreciated that while the inserter mechanisms of the present invention may be used in combination with each other to provide a unique insertion device, each of the mechanisms may be used individually to benefit in combination with known insertion mechanisms. More specifically, the present invention relates to a manually operated insertion mechanism and an insertion device configured to allow for a user selected insertion angle within the range of tilt motion provided by the insertion device.
[0002] It is known in the art to provide insertion devices that insert the cannula at an angle other than 90° to the surface of the patient's skin. This is generally accomplished by use of an inserter having a single pre-determined angle. Alternatively, the inserter may be able to rotate between a number of pre-determined angular orientations. None of the current devices provide for orientation of the cannula at substantially any user selected angle within the range of tilt motion provided by the insertion device.
[0003] It is also known to provide high speed insertion of the cannula by means of power driven, usually spring power, mechanisms. Manual insertion of a cannula is generally a slow process accomplished using a syringe type inserter. None of the current devices provide for manual high speed insertion of the cannula.
[0004] There is, therefore, a need for an insertion device that provides for manual high speed insertion of the cannula at substantially any user selected insertion angle within the range of tilt motion provided by the insertion device.
SUMMARY OF THE INVENTION
[0005] The present invention is an insertion device that provides for manual high speed insertion of the cannula at substantially any user selected insertion angle within the range of tilt motion provided by the insertion device.
[0006] According to the teachings of the present invention there is provided, an inserter for inserting a flexible cannula of a drug delivery device through the skin of a user, the inserter comprising: (a) an inserter housing; (b) a base section detachably connected to the inserter housing such that an interaction between the inserter housing and the base allows the inserter housing to tilt in relation to the base; (c) a manually displaceable plunger deployed in the housing, the plunger displaceable between a stand-by position and an insertion position, the plunger being held in the stand-by position by retaining elements configured in at least one of the inserter housing and the plunger; (d) an insertion needle extending from the plunger in an insertion direction; and (e) a flexible cannula is deployed on the insertion needle for insertion; wherein the manual displacement of the plunger is achieved by applying a force greater than a required force threshold so as to free the plunger from the stand-by position.
[0007] There is also provided according to the teachings of the present invention, an inserter for inserting a cannula of a drug delivery device through the skin of a user, the inserter comprising: (a) an inserter housing; (b) a manually displaceable plunger deployed in the housing, the plunger displaceable between a stand-by position and an insertion position, the plunger being held in the stand-by position by retaining elements configured in at least one of the inserter housing and the plunger; (c) an insertion needle extending from the plunger is an insertion direction; and (d) a flexible cannula is deployed on the insertion needle for insertion; wherein the manual displacement of the plunger is achieved by applying a force greater than a required force threshold so as to free the plunger from the stand-by position.
[0008] According to a further teaching of the present invention, the plunger is configured with at least two retaining spring elements that releasably engage the inserter housing so as to hold the plunger in the stand-by position.
[0009] According to a further teaching of the present invention, the retaining spring elements are outwardly biased such that when the force greater than the required force threshold is applied, the retaining spring elements are inwardly displaced.
[0010] According to a further teaching of the present invention, the inserter housing is configured with at least two retaining spring elements that releasably engage the plunger so as to hold the plunger in the stand-by position.
[0011] According to a further teaching of the present invention, the retaining spring elements are inwardly biased such that when the force greater than the required force threshold is applied, the retaining spring elements are outwardly displaced.
[0012] According to a further teaching of the present invention, there is also provided an automatic retraction mechanism configured to automatically retract the insertion needle.
[0013] According to a further teaching of the present invention, the inserter housing is detachably connected to the base.
[0014] There is also provided according to the teachings of the present invention, an inserter for inserting a cannula of a drug delivery device through the skin of a user, the inserter comprising: (a) an inserter housing; (b) a base section releasably connected to the inserter housing; (c) an insertion needle extending from the plunger is an insertion direction; and (d) a flexible cannula is deployed on the insertion needle for insertion; wherein at least one of the inserter housing and the base includes at least one component that allow the inserter housing to tilt in relation to the base.
[0015] According to a further teaching of the present invention, the base section includes a cannula trap configured to allow the inserter housing to tilt in relation to the base section.
[0016] According to a further teaching of the present invention, the inserter housing is releasably connected to the cannula trap.
[0017] According to a further teaching of the present invention, the cannula trap tilts by rotating about an axis that is parallel to a bottom surface of the base section and passes through the base section.
[0018] According to a further teaching of the present invention, at least one of the inserter housing and the base includes elements that bias the cannula trap to an upright position, such that upon completion of an insertion process with the cannula trap in a tilt position, the cannula trap is automatically returned to an upright position.
[0019] According to a further teaching of the present invention, the inserter housing is configured with a cut-out region that accommodates tilting of the inserter housing in relation to the base.
[0020] According to a further teaching of the present invention, at least one of the inserter housing and the base includes elements that bias the inserter housing to an upright position, such that upon completion of an insertion process with the inserter housing in a tilt position, the inserter housing is automatically returned to an upright position.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] The invention is herein described, by way of example only, with reference to the accompanying drawings, wherein:
[0022] FIG. 1A is a cross sectional view of a first preferred embodiment of an insertion device constructed and operational according to the teachings of the present invention, shown here in an upright position and in a stand-by deployment;
[0023] FIG. 1B is a cross sectional view of the insertion device of FIG. 1A , shown in an upright position and in a insertion deployment;
[0024] FIG. 1C is a cross sectional view of the insertion device of FIG. 1A , shown in an upright position and in a retracted deployment;
[0025] FIG. 1D is a detail of FIG. 1A ;
[0026] FIG. 1E and a detail of the plunger element of the inserter device of FIG. 1A ;
[0027] FIG. 2A is an isometric top view of a base section constructed and operational according to the teachings of the present invention;
[0028] FIG. 2B is a cross sectional view of the base section of FIG. 2A shown with the cannula trap in the upright position;
[0029] FIG. 2C is a cross sectional view of the base section of FIG. 2A shown with the cannula trap in a tilted position;
[0030] FIG. 2D is a detail of the cannula trap of the base section of FIG. 2A ;
[0031] FIG. 3A is a cross sectional view of the insertion device of FIG. 1A shown here in an tilted position and in a stand-by deployment;
[0032] FIG. 3B is a cross sectional view of the insertion device of FIG. 1A , shown in an tilted position and in a insertion deployment;
[0033] FIG. 3C is a cross sectional view of the insertion device of FIG. 1A , shown in an tilted position and in a retracted deployment;
[0034] FIG. 4A is an isometric view of the insertion device of FIG. 1A shown here in an upright position and in a stand-by deployment;
[0035] FIG. 4B is an isometric view of the insertion device of FIG. 1A , shown in an upright position and in an insertion deployment;
[0036] FIG. 5A is an isometric view of the insertion device of FIG. 1A shown here in an tilted position and in a stand-by deployment;
[0037] FIG. 5B is an isometric view of the insertion device of FIG. 1A , shown in a tilted position and in an insertion deployment;
[0038] FIG. 6A is an isometric view of the inserter device of FIG. shown with a protective cap constructed and operational according to the teachings of the present invention;
[0039] FIG. 6B is a side elevation of the device of FIG. 6A ;
[0040] FIG. 6C is a cross sectional view of the device of FIG. 6A ;
[0041] FIG. 7A is a side elevation of the inserter device of FIG. 1A shown here with a plunger locking-element in the locked position;
[0042] FIG. 7B is a side elevation of the inserter device of FIG. 1A shown here with a plunger locking-element partially removed;
[0043] FIGS. 7C and 7D are isometric views of FIG. 7A ;
[0044] FIG. 7E is a cross sectional view of FIG. 7A ; and
[0045] FIG. 8 is a cross sectional view of a second preferred embodiment of an inserter device constructed and operational according to the teachings of the present invention, shown here in a stand-by deployment.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0046] The present invention is an insertion device that provides for manual high speed insertion of the cannula at substantially any user selected insertion angle within the range of tilt motion provided by the insertion device.
[0047] The principles and operation of an insertion device according to the present invention may be better understood with reference to the drawings and the accompanying description.
[0048] By way of introduction, illustrated herein are a number of features that may be used to benefit either individually or in combination. An illustrative example of a first preferred tiltable embodiment of the inserter according to some aspects of the present invention is shown in FIGS. 1-7 of the attached drawings. A non-tiltable second preferred embodiment of the inserter according to other aspects of the present invention is shown in FIG. 8 of the attached drawings. It will be understood that those elements that are common to more than one drawing figure are identified with the same reference numeral.
[0049] It is a feature of the inserters of the present invention that they are configured so as to be manually operated for insertion of the cannula 4 while retraction of the carrier needle 6 may be automatically retracted by use of a spring 8 .
[0050] To this end, as illustrated in FIGS. 1-7 , the insertion plunger 20 is deployed in the inserter housing 30 and retained in a stand-by deployment ( FIGS. 1A and 3A ) such that when a force that exceeds a required threshold is applied by a user, such as by the user's thumb for example, to the insertion plunger 20 in an insertion direction, the insertion plunger 20 breaks free of the stand-by deployment and moves forward so as to insert the carrier needle 6 and cannula 4 into the desired tissue ( FIGS. 1B and 3B ). The stand-by deployment may be maintained by a releasable interlocking arrangement configured to require application of at least a threshold value of force to release it, as illustrated in the drawings here. Alternatively, although not illustrated, the stand-by deployment may be maintained by a frangible (breakable) connecting element which would define the threshold force and also provide tamper evidence.
[0051] It should be noted that due to the amount of force required to pass the force threshold and the short distance traveled by the insertion plunger 20 , it is virtually impossible to noticeably affect insertion before initial penetration sufficient to achieve painless insertion (breaking of nerve cells). There is, however, a possibility that the velocity profile may drop off slightly for the remaining part of the insertion motion, but this is less critical since it is painless.
[0052] As illustrated in the drawings, the first preferred tiltable embodiment 2 of the inserter mechanism of the present invention includes an inserter housing 30 that is configured with a retaining-lip portion 32 and an insertion plunger 20 . The insertion plunger 20 is configured with at least two retaining spring elements 22 that releasably engage the retaining-lip 32 when the insertion plunger 20 is deployed in the stand-by deployment ( FIGS. 1A and 3A ). The insertion plunger 20 also includes a cap 24 to which force is manually applied in order to operate the insertion process. It should be noted that the number of retaining spring elements may be varied dependent on the actual design and may range from as few as one to as many as desired or required for the particular application.
[0053] Extending from the insertion plunger 20 in a direction toward the tissue into which the cannula is to be inserted is a cannula 4 deployed on a carrier needle 6 .
[0054] In operation, this first preferred embodiment 2 of the insertion device of the present invention is placed against the skin surface of the patient with the base section 60 being removably attached to the skin. Force is manually applied to cap 24 and once the required force threshold is reached, the retaining spring elements 22 move inward releasing the insertion plunger 20 from the stand-by deployment and allowing it to move toward the surface of the tissue.
[0055] Upon completion of the outward insertion stroke of the insertion needle 6 , the cannula 4 is forced into the cannula trap 64 and the retraction spring 8 is released so as to retract the insertion needle 6 leaving the cannula 4 in place, now attached to the base section 60 ( FIGS. 1C and 3C ). The inserter housing 30 is then disconnected from the base section 60 which is left attached to the patient with the cannula inserted into the target tissue.
[0056] FIGS. 5A-6E illustrate a protective cap 40 ( FIGS. 5A-5C ) and a plunger locking-element 50 ( FIGS. 6A-6E ). The protective cap 40 and plunger locking-element 50 are designed to protect from unintentional operation of the insertion plunger 20 during shipping and storage up until the time of use.
[0057] The protective cap 40 is deployed on the inserter housing 30 so as to enclose the portion of the insertion plunger 20 that extends outside of the inserter housing 30 .
[0058] The plunger locking-element 50 is deployed so as to extend along a portion of the inserter housing 30 and lockingly engage the insertion plunger 20 so as to prevent movement of the insertion plunger.
[0059] FIG. 7 illustrates a second preferred embodiment of the insertion mechanism of the present invention. This embodiment 100 of the insertion mechanism of the present invention includes an inserter housing 30 ′ that is configured with at least two retaining spring elements 22 ′ and an insertion plunger 20 ′. The insertion plunger 20 ′ is configured with corresponding retaining indentations 26 that are releasably engaged by the retaining spring elements 22 ′ when the insertion plunger 20 ′ is deployed in the stand-by deployment. The insertion plunger 20 ′ also includes a cap to which force is manually applied in order to operate the insertion process.
[0060] Operation of this second preferred embodiment 100 of the insertion device of the present invention is similar to that of the embodiment described above. However, when force is manually applied to the insertion plunger cap and the required force threshold is reached, the retaining spring elements 22 ′ move outwardly releasing the insertion plunger 20 ′ from the stand-by deployment and allowing it to move toward the surface of the tissue.
[0061] While the embodiment illustrated in FIG. 8 is shown in a non-tiltable configuration, it will be appreciated that this embodiment 100 may also be implemented with a base section 60 ′ that allows the inserter housing 30 ′ to be tilted in relation to the base. This is also true of the embodiment 2 of FIGS. 1-7 which is illustrated in a tiltable configuration but can also be provided in a non-tiltable configuration
[0062] As mentioned above, once the cannula has been inserted, the inserter housing 30 ′ is disconnected from the base section 60 ′ which is left attached to the patient.
[0063] It is another feature of the inserters of the present invention is that they are configured so as to be tiltable. Therefore, it will be readily appreciated from FIGS. 1 and 3 - 7 , that the insertion mechanism of embodiment 2 of the present invention may be operated in either an upright position ( FIGS. 1 and 4 ) that is substantially perpendicular to the surface of the tissue or in a tilted position ( FIGS. 3 and 5 ). An example of a suitable arrangement for providing the ability to tilt the inserter housing in relation to the base section is illustrated in FIGS. 2A-2D . However, it will be appreciated that substantially any suitable base section to housing interconnection may be used.
[0064] As illustrated in FIG. 1A , the inserter housing 30 has a “cut-out” region 62 that accommodates tilting of the inserter housing 30 in relation to the disconnectable base section 60 which remains attached to skin of the patient after the cannula 4 has been inserted.
[0065] The tilting is made possible by the interaction of the cannula trap 64 and the base section 60 to which it is attached. As illustrated in FIG. 2D , the cannula trap 64 element includes pivot components 66 which allow the cannula trap 64 to rotate about an axis that is substantially parallel to the plane of the bottom surface of the base 60 , and thereby substantially parallel to the surface of the skin to which the base is attached. The inserter housing 30 which includes the actual insertion mechanism is interconnected to the base section 60 by the cannula trap 64 , thereby allowing the inserter housing 30 to rotate (tilt) with the cannula trap 64 .
[0066] As seen in FIGS. 3A-3C , in this illustrative embodiment the line of insertion along which the insertion needle 6 and cannula 4 travel intersects the axis of rotation of the cannula trap 64 .
[0067] The return leaf springs 68 serve to keep the cannula trap 64 and the inserter housing 30 in a normally upright position and return the cannula trap 64 and the inserter housing 30 to such a position after the insertion process has been completed in order to facilitate disconnection of the inserter housing 30 from the base 60 .
[0068] In operation, the tilt feature of the insertion device of the present invention is placed against the skin surface of the patient with the inserter housing 30 connected to the base 60 , the base section which is removably attached to the skin. The inserter housing 30 is tilted to the desired angle and force is applied to the plunger cap 24 until the required force threshold is reached which releases the plunger 20 and drives the insertion needle 6 with the cannula 4 attached into the patient.
[0069] Upon completion of the outward stroke of the insertion needle, the cannula 4 is forced into the cannula trap 64 and the retraction spring 8 retracts the insertion needle 6 leaving the cannula 4 in place, now attached to the base section and inserted into the tissue of the patient. The inserter housing 30 and the cannula trap 64 are brought back to an upright position and the inserter housing 30 is disconnected from the base section 60 which is left attached to the patient.
[0070] It should be noted that while the cannula is inserted into the patient at an angular orientation, for purposes of connection to the infusion apparatus the top section 70 of the cannula 4 that engages the cannula trap 64 needs to be in an upright orientation after the insertion process is completed. To that end, when the return leaf springs 68 return the cannula trap 64 to the normally upright position after the insertion process has been completed the top section 70 of the cannula 4 is brought to an upright orientation while the portion of the cannula that remains in the patient remains at the angular orientation.
[0071] It will be appreciated that the above descriptions are intended only to serve as examples and that many other embodiments are possible within the scope of the present invention as defined in the appended claims. | An inserter for inserting a needle of a drug delivery device through the skin of a user, the inserter having an inserter housing ( 30 ); a base section ( 60 ) associated with the inserter housing such that an interaction between the inserter housing and the base allows the inserter housing to tilt in relation to the base; a manually displaceable plunger ( 20 ) deployed in the housing, the plunger displaceable between a stand-by position and an insertion position; and an insertion needle ( 6 ) extending from the plunger in an insertion direction; wherein the manual displacement of the plunger is achieved by applying a force greater than a required force threshold so as to free the plunger from the stand-by position. | 0 |
This application is a continuation of Ser. No. 08/716,089, filed Sep. 19, 1996, abandoned.
FIELD OF THE INVENTION
This invention refers to pressure control devices, more particularly to dual pressure level control devices which selectively and controllably attribute to the pressure in a controlled apparatus one of at least two predetermined levels.
BACKGROUND OF THE INVENTION
Many industrial operations require that the pressure in an apparatus should have different values during different operations or operation phases. In many cases, the working cycle of an apparatus, e.g., a press or other apparatus comprising a cylinder and piston or like devices, comprises different phases, one or more of which are active or work phases, while one or more of which are passive or non-work phases. Thus, a piston of a press may have an operating cycle including an active or work stroke and an inactive or return stroke, and different pressures should be obtained in the cylinder, for optimal operation, in the two different strokes. The use of a lower pressure during the non-work phase of the apparatus cycle results, in many cases, in a considerable cost saving. In particular, gas and/or energy consumption may be reduced. In other cases, different operations may require different pressures for optimal efficiency. For instance, an apparatus might require a relatively high pressure to start its operation and then a lower one to maintain the operation over a period of time.
Dual level pressure regulation is effected in the art by providing a separate pressure source or pressure regulator for each desired pressure level. A suitable switch may activate one or the other of said pressure regulators according to the phase of the operating cycle that is taking place.
It is a purpose of this invention to provide a pressure control device which can determine two pressure levels, without requiring two pressure sources or regulators, and permits to control said levels in any desired, even continuous, manner.
It is another purpose of this invention to provide such a pressure control device that is simple, space-saving and free from the danger of malfunctions.
It is a further purpose of this invention to provide a dual pressure level control device that normally determines the higher or the lower of the two pressure levels and correspondingly shifts, when actuated, to the lower or higher level, depending on the chosen embodiment of the invention.
It is a still further purpose of this invention to provide a pressure controlled apparatus, comprising, in combination, a working apparatus of any kind, the operation of which requires the creation and control of a pressure, and a pressure control device according to the invention for carrying out the required pressure control.
Other purposes and advantages of the invention will appear as the description proceeds.
SUMMARY OF THE INVENTION
The pressure control apparatus according to the invention comprises, in combination with a space or chamber in a working apparatus, in which more than one level of a pressure--hereinafter designated as "regulated" or "controlled" pressure"--is to be maintained, with a "source" (or "primary") pressure, with conduit means placing said regulated pressure in communication with said working apparatus space, and with valve means having an open position in which said space is open to said conduit means and a closed position in which said space is sealed off from said conduit means, said regulated pressure in said space creating a pressure thrust on said valve means urging the same to its closed position, pressure level control means comprising elastic means opposing the closure of said valve means by exerting thereon an elastic counterthrust opposed to said pressure thrust, said means being normally in a condition of normal strain or stress wherein it creates a first level of elastic counterthrust such as to be overcome by said pressure thrust when said regulated pressure exceeds a first predetermined level; and means for bringing said elastic means to at least another condition of strain or stress, wherein it creates a second level of elastic counterthrust such as to be overcome by said pressure thrust when said regulated pressure exceeds a second predetermined level.
The pressure control device according to the invention is characterized in that it comprises--in combination with valve means having an open and a closed position and urged to said closed position by a pressure thrust--elastic means opposing the closure of said valve means by exerting thereon an elastic counterthrust opposed to said pressure thrust, said means being normally in a condition of normal strain or stress wherein it creates a first level of elastic counterthrust such as to be overcome by said pressure thrust when it exceeds a first predetermined level; and means for bringing said elastic means to at least another condition of strain or stress, wherein it creates a second level of elastic counterthrust such as to be overcome by said pressure thrust when it exceeds a second predetermined level.
The aforesaid working apparatus, comprising the space in which the regulated pressure is obtained, the source pressure, and the conduit and valve means, are not a part of the invention and may be of any kind, comprising conventional kinds known in the art or other that may be devised by persons skilled in the art.
Preferably, said elastic means of said pressure controlled apparatus or of said pressure control device is a spring, and more preferably, a compression spring. In an embodiment of the invention, the two conditions of strain are two degrees of deformation, preferably of compression, of the spring. More preferably, said degree of deformation is determined by the distance between two portions of the spring and the different conditions of strain are obtained by modifying said distance. Still more preferably, said distance is modified by causing the regulated pressure to exert a force only on one or on both said portions of the spring, to increase or decrease, as the case may be, the elastic counterthrust thereof.
In a particular preferred form of the invention, the spring is a helical one, or has a structure equivalent to a helical structure for the purposes of its elastic behavior, by which is meant that is exerts, when compressed or stretched, an elastic force directed along an axis which is essentially coaxial with the thrust exerted by the regulated pressure on the aforesaid valve means (hereinafter "longitudinal axis") and the different conditions of strain are obtained by applying to said elastic means a control force parallel to said longitudinal axis, e.g., if said elastic means are a spring, on at least one end of the spring. Said control force is produced by applying a pressure, preferably the regulated or controlled pressure, to a force transmitting element. Said element is preferably a member guided for displacement parallel and opposed to said thrust exerted on said valve means, such as a plunger or piston or the like.
In a preferred embodiment of the device, the elastic means and parts cooperating with it are enclosed in a staggered, cylindrical or sleeve-like casing, which is rigidly connected to the valve means housing and coaxial with the valve and houses the aforesaid spring and piston. By "staggered, cylindrical casing" is meant a casing that comprises one or more essentially cylindrical portions solid with or rigidly connected with one another.
The means for bringing said elastic means from their normal strained or stressed condition to their other strained condition preferably include a selection valve, e.g. a solenoid valve, for selectively admitting the regulated or controlled pressure to a chamber, within the pressure control device, wherein it creates a force that is transmitted to the elastic means. In a preferred embodiment of the invention, said selection valve selectively places said chamber in communication with a space in which said regulated pressure exists, or with the atmosphere. The operation of the selection valve may preferably be controlled automatically by programmable control means, e.g. computer means.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 is an axial cross-section of a device according to an embodiment of the invention;
FIG. 2 is a block diagram illustrating an embodiment of the apparatus with which the device of FIG. 1 cooperates;
FIG. 3 is an axial cross-section of a device according to a second embodiment of the invention; and
FIG. 4 is a block diagram illustrating an embodiment of the apparatus with which the device of FIG. 3 cooperates.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
With reference now to FIG. 1, numeral 10 generally designates a casing (shown as broken off) which encloses a chamber 11 that is part of or communicates with the working apparatus space in which pressure control is desired. Source pressure is introduced through any suitable inlet conduit, only schematically indicated at 12, into annular space 13 (gaskets 14 and 15 being provided to prevent escape of pressure) therefrom through ports one of which--port 16--is shown in the drawing, into annular space 17, and ,through a number (in this embodiment three) of circumferentially located passageways, one of which is shown in the drawing at 18 and annular inlet 19 between the valve seat and the valve stem, into chamber 11. The same pneumatic conditions exist, of course, in elements 12, 13, 16, 17 and 18. Valve plunger 20, when closed, seals off the annular passage or inlet 19, through which pressure is admitted into the chamber 11. Said annular inlet is the dividing line between the source pressure and the regulated pressure spaces. The conduit and valve arrangement hereinbefore described is not part of the invention and may be of any suitable type, one particular type thereof being shown only for purposes of illustration.
Plunger 20 is connected to plunger stem 21, which is housed and guided in essentially tubular valve casing 22, mounted in casing 10.
Plunger stem 21 bears, preferably through the interposition of a ball 24, on a disk or cap 25, against which bears the uppermost end 27, hereinafter called the inner end, of a spring 26. The other end of the spring, hereinafter called the outer end, 28, bears against a retaining element hereinafter called dynamic cylinder 30. All the aforesaid elements are retained within a sleeve generally indicated at 31, which is mounted and retained in casing 22 e.g. by being screwed into it. Sleeve 31 is closed at its outer end by a nut 32, screwed into it and provided with bores 33 for tightening it. Said nut 32 retains a core 34. A conduit 38 communicates with chamber 11, as schematically indicated in the drawing, or with any portion of the apparatus in which the regulated pressure exists. Conduit 38, in turn, leads to a valve, e.g. a solenoid valve 41, which is only schematically indicated in the drawing because it is, in itself, a device well known in the art, which communicates through a conduit 35 and a gas inlet 36, with a space 37 defined in said core 34, and may selectively connect said space 37, as schematically indicated in the drawing, with conduit 38, and therefore with chamber 11, or with the atmosphere. When the solenoid valve is actuated to connect conduit 35 with conduit 38, regulated or controlled pressure is admitted to space 37 and bears on the underside of dynamic cylinder 30.
The pressure control apparatus, of which the device of FIG. 1 is the essential component, is diagrammatically illustrated in FIG. 2. Therein the pressure control device of FIG. 1 is generally indicated at 40. Solenoid valve 41, controls the admission of regulated pressure to the device of FIG. 1 or vents the device to the atmosphere. 42 is a supply of source pressure. It will be understood that the source pressure need not be constant. If source 42 is a pressure vessel that contains a given amount of gas, the source pressure will gradually decrease as more of such gas is fed to the working apparatus. Any overpressure in the system is directly released to the atmosphere from relief valve 43.
The operation of the device is as follows.
The regulated pressure in regulated pressure chamber 11 may have two levels, according to the particular operations or process or cycle phases which take place in the particular working apparatus. A primary pressure source feeds gas under pressure through inlet 12 and ports 16, annular space 17, passageway 18 and annular inlet 19, to chamber 11. The admission of gas under pressure ceases when plunger 20 seals off inlet 19. Plunger 20 will seal off inlet 19 when the pressure in chamber 11 has reached such a value that it creates a pressure thrust on plunger 20 that overcomes the elastic counterthrust of spring 26. The thrust on plunger 20 is proportional to the pressure in chamber 11. The elastic counterthrust of spring 26 depends on its condition of strain, specifically, in this particular type of spring, on the distance between the two ends 27 and 28 of the spring itself When plunger 20 is in its open position, the disk or cover 25 and therefore upper end 27 of spring 26 is in its innermost position--its rightmost position as seen in the drawing--and cannot become displaced from that position unless plunger 20 starts to close. If no pressure is admitted through conduit 35 to space 37 below dynamic cylinder 30, this latter is in its outermost position--its leftmost position, as shown in FIG. 1--wherein it bears with its outermost lip 39 against nut 32. Spring 26 is therefore as distended as it can be, and its strain and its elastic counterthrust are at their minimum values. When solenoid 41 is actuated to place conduit 35 in communication with chamber 11, regulated pressure is admitted through conduits 38 and 35 and inlet 36 to space 37, and this causes dynamic cylinder 30 to lift inwards (rightwards, in the drawing) compressing spring 26. Cylinder 30 can lift until the upper surface 45 bears against shoulder 46 of sleeve 31. Under those conditions, the strain of spring 26 and its elastic counterthrust will be higher and a corresponding higher pressure in chamber 11 will be required to cause plunger 20 to close inlet 19. When it is wished to restore the conditions of minimum strain and counterthrust of spring 26, solenoid valve 41 is deactivated to seal off conduit 35 from chamber 11 and place the conduit in communication with the atmosphere, whereby pressure is vented from space 37 and dynamic cylinder 30 returns to its initial or normal position, shown in FIG. 1, allowing spring 26 to become distended as far as is permitted by plunger's lips 39 bearing against nut 32.
Therefore, the pressure in chamber 11 will have two possible levels: a normal low level corresponding to the absence of pressure in the device below dynamic cylinder 30, and a high level corresponding to the admission of pressure to cause the dynamic cylinder 30 to become displaced inwardly and compress spring 26. In this way, by acting on solenoid 41 to admit regulated pressure to a space below the dynamic cylinder or to discharge said pressure therefrom, the regulated pressure in chamber 11 can be set at its high or low value, as desired. It will be appreciated that, instead of causing the regulated pressure to act on dynamic cylinder 30, another source of pressure could be used to act on said cylinder. However this would involve providing an additional source of pressure, and therefore it is less desirable to carry out the invention in this manner. The same consideration applies to any embodiment of the invention.
In the embodiment of FIGS. 3 and 4, the pressure control device also produces in chamber 11 two different regulated pressure values, but the device will cause the pressure to be normally at its higher value.
Once again, numeral 10 generally designates a casing (shown as broken off), which encloses a space 11 that is part of or communicates with the working apparatus in which pressure control is desired. Source pressure is introduced through any suitable inlet conduit, only schematically indicated at 52, into annular space 53 (gaskets 54 and 55 being provided to prevent escape of pressure) therefrom through ports one of which--port 56--is shown, into annular space 57, and, through passageways, one of which is shown in the drawing at 58, and annular inlet 59 between the valve seat and the plunger stem, into chamber 11. Valve plunger 60, when closed, seals off the annular inlet 59. The conduit and valve arrangement hereinbefore described is not part of the invention and may be of any suitable type, one particular type thereof being shown only for purposes of illustration. Plunger 60 is connected to plunger stem 61, which is housed and guided in essentially tubular valve casing 62, mounted in casing 10.
Up to now, there is no significant difference between this embodiment and the one illustrated in FIG. 1. In this embodiment, however, plunger stem 61 bears, preferably through the interposition of a ball 64, on a core 65, which has a staggered cylindrical shape and has a generally T-shaped axial cross-section, and has an upper, cap portion 66 and a lower, tubular portion 67, externally and concentrically of which is located spring 68. The end 70 of spring 68 bears against the underside of cap portion 66 of core 65. The other end 71 of the spring bears against a shoulder 69 of a generally tubular body or sleeve 72, screwed into casing 62, as shown at 73.
As in the first embodiment, regulated pressure may be selectively admitted to the device from chamber 11, or other part of the apparatus in which the regulated pressure exists, through conduit 78, solenoid valve 45 and conduit 75, through inlet conduit 76 which is a perforation of a plug 77. Plug 77, threadedly connected to core 65, is slidable in sleeve 72. A space 80 between plug 77 and sleeve 72 is sealed off by gaskets 81 and 82.
The operation of this embodiment is as follows.
Source pressure is admitted to the device and regulated pressure is built up in chamber 11 as in the embodiment of FIGS. 1 and 2. Regulated pressure normally exists in chamber 11 during the pressure phases of the operation of the working apparatus. When the pressure in the chamber 11 reaches the predetermined desired high level, the force exerted by said pressure on valve plunger 60 exceeds the elastic reaction of spring 68 and the plunger closes the annular space 59 and prevents further pressure increase in the chamber. When it is desired to lower the level of the pressure in chamber 11, regulated pressure is admitted through conduit 78, solenoid 45 and conduit 75, to space 80, where it exerts a pressure on plug 77. The force exerted on plug 77 urges plug 77 and core 65 downwards--"downwards" as seen in FIG. 3--viz. away from plunger stem 61 and chamber 11. This tends to compress spring 68 and therefore reduces its elastic reaction, so that a lower pressure in chamber 11 is required to cause plunger 60 to seal annular space 59 and prevent pressure increase in chamber 11. When it is desired to return to the higher regulated pressure condition, solenoid valve 45 is deactivated to place conduit 75 in communication with the atmosphere.
In the diagrammatic illustration of FIG. 4, analogous to FIG. 2, the pressure control device of FIG. 3 is generally indicated at 44 and the solenoid valve indicated at 45 controls the admission of gas under regulated pressure to the device of FIG. 3 as well as the discharge of said pressure to the atmosphere from the pressure control device of FIG. 3 through the conduit 75. However, while in the apparatus of FIG. 2 only one pressure relief valve is provided, this embodiment includes a high pressure relief valve 47 and a low pressure relief valve 48.
It will be clear to persons skilled in the art that the invention permits continuous pressure control by continuous variation of the control pressure. Thus in both configurations, e.g. of FIGS. 1 and 3, and their relative control schemes as in FIGS. 2 and 4 accordingly, the controlled pressure level can be varied by control means of the solenoid valve, e.g. a PWM (pulsed wave modulation) control. An example of implementation is a robot "gripper" with closed loop force or torque control.
While specific embodiments of the invention have been described by way of illustration, it will be understood that they are not limitative and that the invention may be carried into practice with many modifications, variations and adaptations, without departing from its spirit or exceeding the scope of the claims. | Pressure control device, characterized in that it comprises, in combination with valve means having an open and a closed position and urged to said closed position by a pressure thrust, elastic means opposing the closure of said valve means by exerting thereon an elastic counterthrust opposed to said pressure thrust, said means being normally in a condition of normal strain or stress wherein it creates a first level of elastic counterthrust such as to be overcome by said pressure thrust when it exceeds a first predetermined level; and means for bringing said elastic means to at least another condition of strain or stress, wherein it creates a second level of elastic counterthrust such as to be overcome by said pressure thrust when it exceeds a second predetermined level. | 8 |
BACKGROUND OF THE INVENTION
1. Field Of The Invention
This invention relates to an approach roller feed bed for cooling beds for the retardation and transverse conveyance of metal lengths of varying cross sections and approach speeds, consisting of conveyor rollers inclined transversely with respect to the conveying line, a longitudinal braking section next to the cooling bed for the retardation of thick profile sections, and a longitudinal braking section, away from the cooling bed and covered by movable covering means, for the retardation and conveyance of thin profile sections. The retardation and conveyance of the lengths occurs by means of braking means which can be raised and lowered and the longitudinal sections and their braking means can be operated independently of one another.
2. Description Of The Prior Art
A device of the above named type is already disclosed in the German Auslegeschrift No. 1 289 813, in which either thick profile sections at a low approach speed or thin profile cross sections at a higher approach speed, in lengths, are retarded and conveyed to the cooling bed. The lengths of varying profile cross sections initially approach in a common channel spaced from the cooling bed and after overflow are retarded in succession in stages in two brake channels lying adjacent to one another or in the brake channel adjacent the cooling bed, and are conveyed to the cooling bed. The approach channel and the first brake channel are covered on the top with pivotable covering means in order to prevent the fast-moving lengths of thin profile sections from jumping out of the approach channel or the first brake channel. This device has the disadvantage that in particular the lengths approaching at a higher approach speed require an overflow time before the first brake channel can commence retardation.
BRIEF SUMMARY OF THE INVENTION
The object of the invention is to avoid the disadvantages of the previously known device, in particular to shorten the operating cycle of the braking means for the lengths approaching at a higher speed in two parallel lines, and thus to enable lengths with an approach speed or more than 20 m/sec to be retarded and conveyed to the cooling bed, with the same or a lesser cooling bed length. Another object of the invention is further to shorten the retardation of the lengths by the use of additional braking means.
According to the invention it is proposed that adjacent to the cooling bed three longitudinal braking sections with braking means which can be raised and lowered are arranged, of which the inner longitudinal section, next to the cooling bed, is separated from the other two sections by a narrow separation means section which can be raised and lowered, the other two longitudinal braking sections are separated from one another by a channel wall, and movable covering means are associated in each case with the longitudinal sections; when the braking means are lowered the central longitudinal section forms an approach channel for the inner braking section; and with braking means which can be raised and lowered the central and outer braking sections are jointly operable alternately with one another. The advantage of such a device is that the lengths at a high approach speed do not need to be conveyed from an approach channel into a brake channel, but can immediately run directly into one or the other of two brake channels in alternation and the retardation process can be initiated without any loss of time.
A diverter may be arranged upstream of the central and outer braking sections with the central longitudinal braking section forming an extension of the rolling line. The covering means can in each case according to the embodiment be firmly connected to the braking means, for instance the braking means simultaneously forming the covering means and being constructed as slides which can be raised and lowered. Alternatively the covering means can rise and fall or pivot independently of the braking means. Rising and falling push rods, or hydraulic or pneumatic power means, can be used as a lifting means for the covering means. The covering means of the three longitudinal sections form a sliding surface inclined towards the cooling bed. The backs of the covering means and the inner braking section can also form a sliding surface inclined towards the cooling bed. The covering means can be raised and lowered in dependence on the braking means motion, however they can also be constructed so as to be movable independently of one another. The covering means can be provided with brake shoes as additional braking means, constructed so as to pivot under the action of resilient power means. The covering means can be constructed as slides overlapping the braking means, the two longitudinal braking sections away from the cooling bed being provided with air blast ducts directed towards the braking means, as additional braking means. Air outlet ducts are associated with the air blast ducts in the region of the braking sections. Groups of linear motors can also be associated as additional braking means with the two braking sections away from the cooling bed. In this case the linear motors are placed above the braking sections so as to be raised or lowered or pivoted. The braking sections are arranged in the conveying direction in the region below the motor stators. Longitudinal sections with spacer slides are arranged adjacent to the braking means.
DESCRIPTION OF THE DRAWINGS
The invention will now be described in detail with reference to the accompanying drawings wherein:
FIG. 1 is a schematic cut-away plan view of an approach roller feed bed with a cooling bed in accordance with the invention,
FIG. 2 is a schematic cross section of an embodiment of the approach roller feed bed of the invention,
FIG. 3 is a schematic cross section of a further embodiment of the approach roller feed bed,
FIG. 3a is a cut-away cross section of the approach roller feed bed according to FIG. 3, set for conveying thick profile sections;
FIG. 4 is a schematic cross section showing the covering means and air brakes as additional braking means,
FIG. 4a shows the air brakes of FIG. 4 in elevation, and
FIG. 5 is a schematic cross section showing an embodiment of the covering means with linear motors as additional braking means.
DETAILED DESCRIPTION
In FIGS. 1 and 2 an approach roller feed bed is designated by 1 which is interspersed transversely with respect to the conveying direction R with conveyor rollers 1a inclined towards the cooling bed 2. The conveyor rollers 1a have individual drives 1b. Rolled metal stock is divided on the approach roller bed 1 by means of parting shears S into lengths T which are conveyed in succession, retarded until they are almost at a standstill and transversely conveyed into the fixed rakes 2a of the cooling bed 2 for further cooling. The approach roller feed bed 1 is divided into three longitudinal braking sections A, B, C lying side by side and parallel to one another, consisting of braking means 4, 5 and 6 which can be raised and lowered. The braking means 4 form an outer longitudinal section A at the side away from the cooling bed 2, with pivotable covering means 4a. The covering means 4a are hinged at one end to a piston rod 7a of a piston guided in a cylinder 7. The cylinder 7 is secured by hinges to a bracket 9.
The braking means 5 form a central longitudinal section B, with covering means 5a which can be raised and lowered by means of rams 5b. The braking means 6 form an inner longitudinal section C next to the cooling bed 2. The backs of the covering means 4a and 5a when lowered and the braking means 6 when raised form a slide or ramp inclined with respect to the cooling bed 2 for transversely conveying the lengths T.
The inner longitudinal section C is separated from the central longitudinal section B by a longitudinal section with separation means 3 which can be raised and lowered. The outer longitudinal section A is divided from the central longitudinal section B by a fixed channel wall 8. Brake slides known per se which can be raised and lowered form the braking means 4, 5 and 6.
A distinction must be made between the supply, retardation and transfer of lengths T of rolled stock at a high approach speed, more than about 20 m/sec, and a cross section of approximately 8 to 25 mm diameter, alternately in the longitudinal sections 4 and 5, on the one hand, and the supply, retardation and transfer of lengths T of rolled stock at a lower approach speed of less than 20 m/sec and a cross section of approximately 16 to 50 mm diameter from the longitudinal section 5 via the longitudinal section 6 on the other hand.
For instance, if the first length T runs from a rolling mill, (not illustrated) after the parting of the rolled bar into lengths T on the approach roller feed bed 1, to the conveyor rollers 1a at a rolling speed of more than 20 m/sec, this first length T is guided into the outer longitudinal braking section A by appropriate setting of the diverter switch 10. The braking means 4 are lowered below the upper edge of the conveyor rollers 1a. When the length T with a thin rolled stock cross section has run far enough into the region of the cooling bed 2, the braking means 4 are lifted and the length T is retarded. The covering means 4a, for instance pivotable covering plates, are then swivelled up by the piston in the cylinder 7 so that the length T slides over the upper edge of the fixed channel wall 8, over the lowered covering means 5a and the upper surface of the raised braking means 6 into the first notch of the fixed rakes 2a of the cooling bed 2. Subsequently the braking means 4 and the covering means 4a are again lowered. The following length T, at an approach speed of more than 20 m/sec and with a thin rolled stock cross section, is guided, by reversal of the diverter 10 in the rolling line W, into the central longitudinal braking section B. The braking means 5 are lowered below the upper edge of the conveyor rollers 1a. When the length T has run far enough into the region of the cooling bed 2 the braking means 5 are lifted and the length T is retarded. The covering means 5a are raised by lifting the rams 5b so that the length T is diverted over the separation means 3, located in its upper position, and the braking means 6, located in its upper position, after lifting of the vertically movable bars 2b, into the first notch of the fixed rakes 2a of the cooling bed 2.
The movable rakes (not shown) of the cooling bed 2 convey the two lengths T a space further. The bars 2b, the braking means 5, and the covering means 5a are lowered. The longitudinal braking sections A and B are now ready for a new operating cycle in which further lengths T run in succession at a high approach speed on the approach roller conveyor 1.
In contrast, if the first length T is of slow-moving relatively thick stock, for example with a rolled stock speed of less than 20 m/sec and a cross section of approximately 16 to 50 mm diameter, this first length T is guided via the diverter 10 into the central longitudinal braking section B, with braking means 5 in the lowered position. As soon as the length T has run in far enough the separation means 3 is lowered and the length T runs over on the conveyor rollers 1a into the region of the inner longitudinal section C of which the braking means 6 are lowered below the upper edge of the conveyor rollers 1a. By lifting the braking means 6 the length T is lifted from the upper surfaces of the conveyor rollers 1a and retarded and slides over the upper edge of the fixed rakes into the first notch of the fixed rakes 2a of the cooling bed 2. The movable rakes convey the length T a space further on the cooling bed 2 while the inner braking means 6 is lowered into its lower position and the separation means 3 is again lifted into its upper position. Subsequently the following length T again runs into the central longitudinal section B, as already described.
In FIGS. 3 and 3a a further embodiment of the approach roller feed bed with a cooling bed arranged adjacent thereto is illustrated, there being no essential difference in the method of operation with respect to FIG. 2. Elements corresponding to those shown in FIGS. 1 and 2 are identified by the same numerals increased by 10. Thus, in FIGS. 3 and 3a the approach roller feed bed with conveyor rollers 11a is designated by 11, the conveyor rollers 11a being arranged transversely with respect to the conveying direction R and inclined towards the cooling bed 12. The conveyor rollers 11a also have individual drives and are interspersed in the approach roller feed bed 11. On the approach roller feed bed 11 rolled stock of varying cross sections and profile form is divided into lengths T which are successively supplied, retarded and transversely conveyed, for further cooling, into the fixed rakes 12a of the cooling bed 12.
The approach roller feed bed 12 is divided into three longitudinal sections A, B, C lying parallel to one another, consisting of braking means which can be raised and lowered. The outer braking means 14 form the longitudinal section A away from the cooling bed 12, pivotable covering means 14a for the braking channel being associated with the longitudinal section A in order to prevent the lengths T from jumping out. The covering means 14a are pivotable at one end by means of a rocking shaft 17. In the covering means 14a air ducts 14b are provided, directed onto the length T in order to produce pressure forces as additional braking means by the action of the air blast so that the length T is urged into the left corner of the channel and thus on the one hand the coefficient of friction is increased during retardation and on the other hand quieter running of the length T is caused.
The braking means 15 forms the central longitudinal section B with which slides 15a, which can be raised and lowered and having covering means, are associated. The slides 15a overlap the braking means 15 and close the braking channel at the top with the covering means in order to prevent the lengths T from jumping out upwardly when they are conveyed thereto. Air ducts 15b directed at the length T are formed in the slides 15a through which air ducts 15b air is blown onto the lengths T so that an additional pressing force is exerted on the latter against the lower and lateral guide surfaces during retardation. The central longitudinal section 15, 15a is separated from the longitudinal section 14, 14a by a channel wall 18 and from the inner longitudinal section C with braking means 16 by means of a longitudinal section with separation means 13 which can be raised and lowered. Air ducts 13a are provided in the separation means 13 of the longitudinal section to extract the blast air.
Instead of the air ducts 14b, 15b as additional braking means, pivotably mounted brake shoes 24 can also be arranged on the lower side of the covering means 14a, 15a as shown in FIG. 4.
The braking means 16 are C-shaped and in the raised position simultaneously form the covering means. The backs of the covering means 14a, 15a when lowered and the braking means 16 when raised form a ramp or slide inclined towards the cooling bed 12 for transversely conveying the lengths T. Braking shoes or slides known per se which can be raised and lowered form the longitudinal sections with braking means 14, 15 and 16.
The operation of the apparatus shown in FIGS. 3 and 3a is analogous to that of FIG. 2. In the case of lengths T of rolled stock with an approach speed of more than approximately 20 m/sec and a cross section of approximately 8 to 25 mm, the first length T runs from a rolling mill, after parting into lengths T, on the approach roller feed bed 11, and is guided into the outer longitudinal braking section A. The braking means 14 are lowered below the upper surfaces of the conveyor rollers 11a. After the length T has run far enough into the region of the cooling bed, the braking means 14 are lifted and the length T is retarded. The covering means 14a, for instance pivotable covering plates, are swivelled up by operation of the rocking shaft 17 so that the length T is diverted over the upper edge of the fixed channel wall 18 and over the lowered covering means 15a and the top of the lifted braking means 16 into the first notch of the fixed rakes 12a of the cooling bed 12. Subsequently the braking means 14 and the covering means 14a are again lowered. The following length T is guided, after reversal of the diverter 10, into the central longitudinal section B, with the braking means 15 lowered below the upper surface of the conveyor rollers 11a. After the length T has run far enough into the region of the cooling bed 12 the braking means 15 are lifted and the length T is retarded. The covering means 15a are raised by lifting the T-shaped slide so that the length T is diverted, over the separation means 13 located in its upper position and the back of the lifted braking means 16, after lifting the bars 12b, into the first notch of the fixed racks 12a of the cooling bed 12.
The movable rakes of the cooling bed 12 convey the two lengths T a space further. The bars 12b, the braking means 15, and the covering means 15a are then again lowered. The longitudinal braking sections A, B are then ready for a new operating cycle in which further lengths T approach the approach roller feed bed 11 at a high approach speed. If the lengths T approaching the braking means 14 or 15 are to be subjected to a braking force additional to the braking forces exerted when the braking means 14, 15 are lifted, air is blown through the air ducts 14b or 15b onto the length T which is running in, the air pressure forces causing an increased frictional force on the sliding surfaces guiding the length T. Apart from a further shortening of the braking path, additional quiet running of the lengths T approaching at a high speed is also obtained when compressed air is blown on. The air is drawn off downwardly by air ducts 14c or 13a laterally of the conveyor rollers 11a.
In the case of rolled parted lengths T with a rolled stock speed of less than 20 m/sec and a cross section of approximately 16 to 50 mm diam, a length T is guided by the diverter 10 into the longitudinal section B, with braking means 15 in the lowered position. The slide, overlapping the braking means 15, of the covering means 15a is lifted, as shown in FIG. 3a, so that the free space above the braking means 15 is extended for the thick cross sections. The braking means 16 is lowered below the conveying plane. When the length T has run into the region of the cooling bed 12, the initially raised separation means 13 is lowered and the length T shifts on the conveyor rollers 11a into the region of the inner longitudinal section C with braking means 16 lowered. By lifting the braking means 16 the length T is lifted from the conveyor rollers 11a, is retarded and slides over the upper edge of the fixed rakes 12a of the cooling bed 12. The movable rakes convey the length T a space further on the cooling bed 12 while the braking means 16 is lowered and the separation means section 13 is again lifted. Subsequently the following length T runs into the longitudinal section B.
In FIGS. 4 and 4a a further embodiment of the approach roller feed bed is illustrated. Parts corresponding to those in FIG. 4 have the same reference numbers. The covering means 14a and 15a are constructed so as to be raised and lowered or pivoted as described above. Additional brake shoes 24, 25 are pivotably secured to the covering means 14a and 15a, on their sides facing the braking means 14, 15. The brake shoes 24, 25 are secured by a suspension pin 26 approximately at their center of gravity, to the covering means 14a, 15a approximately in the horizontal plane parallel to the conveying line R. In order to influence the horizontal position of the brake shoes when a length T runs in or through, compressed air can be blown onto either end of the brake shoes 24, 25 by means of air nozzles 27, 28. The air nozzles 27, 28 are arranged in the covering means 14a and 15a above the free ends of the brake shoes 24, 25 and can be controlled by valves 29, 30.
As soon as the leading end of a length T passes the longitudinal section with brake shoes 24 or 25, the valves 29 are opened so that air is blown through the air nozzles 27 onto the front (downstream) end of the brake shoes 24, 25 so that the rear (upstream) end of the brake shoes 24 or 25, as illustrated by broken lines, is slightly raised and the leading end of the length T passing through is not obstructed by the brake shoes 24 or 25, even in the case of unquiet running. When the leading end of the length T has run through, the air nozzles 27 are turned off by reversing the associated valve 29 so that the supply of air is interrupted. The valve 30 associated with the air nozzles 28 is then opened and the air nozzles 28 are supplied with blast air, and the rear ends of the brake shoes 24 or 25 bear on the surface of the lengths T and exert an additional braking force upon the latter. The intensity of the additional braking can be influenced by altering the pressure of the air blown onto the rear ends of the brake shoes 24 or 25. The action of the brakes 24 or 25 on the length T passing through is in addition to the braking force exerted by the braking means 14 or 15 in the manner described above.
Instead of the air nozzles 29, 30 other resilient means such as springs or electromagnets can also be associated with the brake shoes 24 or 25. The brake shoes 24 or 25 can be pivotably suspended on parallelogram links.
In a further embodiment according to FIG. 5 the covering means associated with the longitudinal braking sections having braking means 34 or 35a are constructed as linear electric motors 36 or 37. The linear motors 36 are secured to rocking levers 34a movable about pivot shafts 34b while the linear motors 37 are laterally connected to slides 35c which can be raised and lowered. The linear motors 36 and 37 have stators 36a and 37a conducting the magnetic flux (electromagnetic travelling field) on which are seated windings 36b and 37b which are offset with respect to one another. The linear motors 36, 37 are surrounded by housings. Below the stator 36a or 37a is a respective longitudinal braking section with braking means 34 and 35a which can be raised and lowered and which simultaneously forms the return plate for the magnetic flux. Guide plates which do not conduct the magnetic flux are arranged to the side of the braking means section 34 in the conveying direction R below the cross sections of the windings 36b. To the side of the braking means section 35a in the conveying direction R below the cross sections of the windings 37b are a longitudinal section with spacer slides 35b which can be raised and lowered and a bar on the slide 35c, which consist of a material, for instance cast iron, which does not conduct the magnetic flux.
If, as already described above with respect to FIGS. 2 and 3, rolled length T with a thin cross section and an approach speed of more than 20 m/sec runs on the conveyor rollers 11a of the approach roller feed bed 11 via the diverter 10 into the braking section A, the latter is lifted with its upper edge above the conveying plane of the conveying rollers 11a, until the length T is in the region of the air gap which extends between the lower edge of the stator 36a of the linear motor 36 and the upper edge of the braking means 34. The linear motors 36 are then switched on so that an electrical alternating voltage is applied to the magnetic coils 36b and the magnet coils 36b produce an electromagnetic travelling field which exerts a magnetic force in the length T opposite to the conveying direction R which results in an additional braking action in addition to the retardation of the length T caused by the sliding friction on the braking means 34. Moreover the magnetic field brings about quieter running of the length T. As soon as the length T has been sufficiently retarded the linear motors 36 are turned off and swivelled out upwardly around the swivel axis 34b, and the braking means 34 is further lifted to the upper edge of the lateral guides so that the length T slides down the sliding surface inclined towards the cooling bed 12, into the first notch of the cooling bed 12. Subsequently the braking means 34 and the linear motors 36 are moved back into their initial position.
After the reversal of the diverter 10 the following length T with a thin cross section and an approach speed of more than 20 m/sec is conveyed on the approach roller feed bed 11 into braking section B. While the spacer slide section 35b has already been lifted to below the upper edge of the part of the magnet coil 37b nearer the cooling bed, by lifting the braking means 35a above the upper surface of the conveyor rollers 11a the length T is lifted to the region of the air gap between the lower edge of the stator 37a and the upper edge of the braking means 35a indicated by broken lines. In this case the length T is retarded as a result of the sliding friction and by switching on the linear motors 37 a magnetic travelling field is produced in the windings of the linear motors 37 by the applied a.c. voltage, the magnetic travelling field producing in the length T a magnetic force in the opposite direction to the conveying direction. Moreover quieter running of the length T is obtained by the magnetic field. The slide section 35c bearing the linear motors 37 is lifted to the extent that with the further lifting of the braking means 35a and the spacer slide section 35b to the upper edge of the sliding ramp surface inclined towards the cooling bed 12 the length T can slide off into the following notch of the cooling bed 12. Subsequently the braking means 35a, the spacer slide 35b and the slide 35c bearing the linear motors 37 are again moved back into their initial positions.
The braking means which can be raised and lowered, and the separation means as well as the other slides mentioned, are pivotably mounted in a known manner preferably on an axis X arranged below the slide and transverse with respect to the conveying direction R, and are actuated by way of pull or push rods (not illustrated).
The motion of the covering means by swivelling or lifting or lowering can occur in dependence on the motion of the associated braking means or independently thereof.
In a known way, it is also possible with the devices illustrated to lift out the lengths T from the inner braking sections C by means of the movable rakes.
It is also conceivable to provide three or more braking sections for the retardation of the lengths T at a high approach speed (more than 20 m/sec) instead of two braking sections A, B.
Finally it would also be possible to retard the lengths T, when the covering means 4a, 5a; 14a, 15a are closed and when the braking means 4, 5; 14, 15 are lowered, by the braking means 6, 16 and to convey the lengths T to the cooling bed 2, 12; the channel wall 8, 18 as well as the separation means 3, 13 would have to be constructed so as to be raised and lowered. | Rolled stock running out of a rolling mill is parted into lengths suitable for the cooling bed. Rolled stock cross sections of various sizes are retarded both at approach speeds of more than approximately 20 m/sec and slower, alongside the cooling bed in an approach roller feed bed and then transversely conveyed over the cooling bed. In order to avoid requiring an uneconomically long cooling bed as a result of the sequence times of the lengths of rolled stock, three or more longitudinal braking sections are arranged side by side to enable thin lengths at a high approach speed to be retarded in rapid succession and conveyed across to the cooling bed. Covering means of the braking sections are constructed to provide additional retardation of the lengths, e.g. by blowing air, by lowering brake shoes or by the action of linear electromagnetic motors. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to the use of Abnormal Cannabidiols to lower the intraocular pressure of mammals and thus are useful in treating glaucoma.
2. Background of the Related Art
Ocular hypotensive agents are useful in the treatment of a number of various ocular hypertensive conditions, such as post-surgical and post-laser trabeculectomy ocular hypertensive episodes, glaucoma, and as presurgical adjuncts.
Glaucoma is a disease of the eye characterized by increased intraocular pressure. On the basis of its etiology, glaucoma has been classified as primary or secondary. For example, primary glaucoma in adults (congenital glaucoma) may be either open-angle or acute or chronic angle-closure. Secondary glaucoma results from pre-existing ocular diseases such as uveitis, intraocular tumor or an enlarged cataract.
The underlying causes of primary glaucoma are not yet known. The increased intraocular tension is due to the obstruction of aqueous humor outflow. In chronic open-angle glaucoma, the anterior chamber and its anatomic structures appear normal, but drainage of the aqueous humor is impeded. In acute or chronic angle-closure, the anterior chamber is shallow, the filtration angle is narrowed, and the iris may obstruct the trabecular meshwork at the entrance of the canal of Schlemm. Dilation of the pupil may push the root of the iris forward against the angle, and may produce pupilary block and thus precipitate an acute attack. Eyes with narrow anterior chamber angles are predisposed to acute angle-closure glaucoma attacks of various degrees of severity.
Secondary glaucoma is caused by any interference with the flow of aqueous humor from the posterior chamber into the anterior chamber and subsequently, into the canal of Schlemm. Inflammatory disease of the anterior segment may prevent aqueous escape by causing complete posterior synechia in iris bombe, and may plug the drainage channel with exudates. Other common causes are intraocular tumors, enlarged cataracts, central retinal vein occlusion, trauma to the eye, operative procedures and intraocular hemorrhage.
Considering all types together, glaucoma occurs in about 2% of all persons over the age of 40 and may be asymptotic for years before progressing to rapid loss of vision. In cases where surgery is not indicated, topical α-adrenoreceptor antagonists have traditionally been the drugs of choice for treating glaucoma.
Certain Abnormal Cannabidiols are disclosed in Howlett et al, “International Union of Pharmacology. XXVII. Classification of Cannabinoid Receptors”, Pharmacological Reviews 54:161-202, 2002.
Reference is made to Published U.S. Patent Application Nos. 2005/0282902, 2005/0282912 and 2005/0282913 to Chen et al which were published on Dec. 22, 2005 and are herein incorporated by reference thereto. (June Chen is a co-inventor of each of said published patent applications and the present patent application.)
SUMMARY OF THE INVENTION
We have found that Abnormal Cannabidiols are potent ocular hypotensive agents. We have further found that Abnormal Cannabidiols and homologues and derivatives thereof, are especially useful in the treatment of glaucoma and surprisingly, cause no or significantly lower ocular surface hyperemia than the other compounds that are useful in lowering intraocular pressure, e.g. PGF 2α and lower alkyl esters thereof.
The present invention relates to methods of treating ocular hypertension and glaucoma which comprises administering an effective amount of a compound represented by the formula I
Y is selected from the group consisting of O and OH;
Z is N or C;
Q is selected from the group consisting of
W is a direct bond or C(R 11 )(R 12 );
a dotted line represents the presence or absence of a double bond;
R is selected from the group consisting of H, halogen, e.g. bromo or chloro; and C 1-5 alkyl;
R 1 is selected from the group consisting of H and halogen, e.g. bromo or chloro;
R 2 is independently selected from the group consisting of H, C 1-5 alkyl, halogen, XC 1-5 alkyl, C 1-5 alkylOR 13 , C 1-5 alkylN(R 13 ) 2 , N(R 13 ) 2 , XC 1-5 alkylN(R 13 ) 2 and XC 1-5 alkylOR 13 ;
X is O or S(O) n ;
n is 0 or an integer of from 1 to 2;
R 3 is selected from the group consisting of H, hydroxyl, C 1-5 alkyl, C 1-5 alkylOR 13 and C 1-5 alkylN(R 13 ) 2 ;
R 4 is selected from the group consisting of H, C 2-5 alkenyl, e.g. isopropenyl, C 1-5 alkyl, C 1-5 alkylOR 13 and C 1-5 alkylN(R 13 ) 2 ;
R 5 , R 6 , R 7 , R 8 , R 9 , R 10 , R 11 , R 12 are independently selected from the group consisting of H, C 1-5 alkyl, C 1-5 alkylOR 13 and OR 13 ; and
R 13 is selected from the group consisting of H, C 1-5 alkyl and C 3-8 cyclic alkyl, or two R 13 groups, together with N or O, may form a cyclic ring such as a piperidine or morpholine ring; and provided that any of said alkyl groups may be substituted with a hetero atom containing radical, wherein said heteroatom is selected from the group consisting of halogen, e.g. fluoro, chloro or bromo, oxygen, nitrogen and sulfur, e.g. hydroxyl, amino, nitro, mercapto, etc.;
R 8 and R 12 may, together, form a cyclic ring;
and R 3 and R 5 may, together, represent O, and
when Q is menthadiene, R 1 and R 2 are H and Y is hydroxyl, R may not be H or alkyl.
In a further aspect, the present invention relates to pharmaceutical compositions comprising a therapeutically effective amount of a compound of formulae (I), in admixture with an non-toxic, pharmaceutically acceptable liquid vehicle. Such pharmaceutical compositions may be ophthalmic solutions which are useful in treating ocular hypertension and/or glaucoma. Finally, the present invention provides certain novel compounds which are useful in treating ocular hypertension and/or glaucoma.
DETAILED DESCRIPTION OF THE INVENTION
The present invention relates to the use of Abnormal Cannabidiols as ocular hypotensives. These therapeutic agents are represented by compounds having the formula I, above.
In one embodiment of the invention, the compound is selected from the group consisting of abnormal Cannabidiols and analogues thereof represented by formula II.
wherein Q is selected from the group consisting of
wherein R, R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , R 10 , R 11 , R 12 and Q are as defined above and Y 1 is R 3 and R 5 , or O, or OH.
A particularly preferred group represented by Q is menthadiene or
In this class of compounds, preferably, R is selected from the group consisting of hydrogen, methyl, bromo and chloro and R 1 is selected from the group consisting of hydrogen, methyl and chloro.
Compounds of this type may be prepared by condensation of a cyclic alkene or cyclic alcohol with a suitably substituted benzene-1,3-diol. The reaction is catalysed by an acid such as oxalic acid dihydrate or p-toluenesulphonic acid. The reaction is carried out in a solvent or mixture of solvents such as toluene, diethyl ether or dichloromethane. A mixture of the two isomers is obtained and the desired product is separated by chromatography. The reaction scheme is illustrated below.
The synthesis of the starting materials is well known.
The mechanism of the reaction is the result of the formation of a carbocation by elimination of OH or a starting material containing a functional group such as acetate which can also be eliminated to give the carbocation can be used.
In another embodiment of the invention the compound is tetrahydropyridine represented by formula III.
These tetrahydropyridine compounds may be synthesized according to the following reaction scheme wherein Me is methyl, Bu is butyl and iPr is isopropyl.
In a further embodiment of the invention, the group Q may be substituted by a carbonyl or hydroxy group. These compounds may be prepared by the following schemes
As described in JACS, 1989, 8447-8462
In a further embodiment of the invention, the compound is a piperidinedione represented by the formula IV
These compounds may be synthesized according to the following reaction scheme wherein Et is ethyl, THF is tetrahydrofuran and DCM is dichloromethane.
An alternative base and solvent for the cyclisation is potassium carbonate, 18-crown-6 in toluene at reflux or sodium hydride in cyclohexane at reflux, as described by I. V. Micovic et al, J. Chem. Soc. Perkin I, 1996, 2041-2050. The decarboxylation can also be carried out with 10% aqueous oxalic acid.
In all of the above formulae, as well as in those provided hereinafter, the straight lines represent bonds. Where there is no symbol for the atoms between the bonds, the appropriate carbon-containing radical is to be inferred.
Pharmaceutical compositions may be prepared by combining a therapeutically effective amount of at least one compound according to the present invention, as an active ingredient, with conventional ophthalmically acceptable pharmaceutical excipients, and by preparation of unit dosage forms suitable for topical ocular use. The therapeutically efficient amount typically is between about 0.0001 and about 5% (w/v), preferably about 0.001 to about 1.0% (w/v) in liquid formulations.
For ophthalmic application, preferably solutions are prepared using a physiological saline solution as a major vehicle. The pH of such ophthalmic solutions should preferably be maintained between 4.5 and 8.0 with an appropriate buffer system, a neutral pH being preferred but not essential. The formulations may also contain conventional, pharmaceutically acceptable preservatives, stabilizers and surfactants.
Preferred preservatives that may be used in the pharmaceutical compositions of the present invention include, but are not limited to, benzalkonium chloride, chlorobutanol, thimerosal, phenylmercuric acetate and phenylmercuric nitrate. A preferred surfactant is, for example, Tween 80. Likewise, various preferred vehicles may be used in the ophthalmic preparations of the present invention. These vehicles include, but are not limited to, polyvinyl alcohol, povidone, hydroxypropyl methyl cellulose, poloxamers, carboxymethyl cellulose, hydroxyethyl cellulose and purified water.
Tonicity adjustors may be added as needed or convenient. They include, but are not limited to, salts, particularly sodium chloride, potassium chloride, mannitol and glycerin, or any other suitable ophthalmically acceptable tonicity adjustor.
Various buffers and means for adjusting pH may be used so long as the resulting preparation is ophthalmically acceptable. Accordingly, buffers include acetate buffers, citrate buffers, phosphate buffers and borate buffers. Acids or bases may be used to adjust the pH of these formulations as needed.
In a similar vein, an ophthalmically acceptable antioxidant for use in the present invention includes, but is not limited to, sodium metabisulfite, sodium thiosulfate, acetylcysteine, butylated hydroxyanisole and butylated hydroxytoluene.
Other excipient components which may be included in the ophthalmic preparations are chelating agents. The preferred chelating agent is edentate disodium, although other chelating agents may also be used in place of or in conjunction with it.
The ingredients are usually used in the following amounts:
Ingredient
Amount (% w/v)
active ingredient
about 0.001-5
preservative
0-0.10
vehicle
0-40
tonicity adjustor
1-10
buffer
0.01-10
pH adjustor
q.s. pH 4.5-7.5
antioxidant
as needed
surfactant
as needed
purified water
as needed to make 100%
The actual dose of the active compounds of the present invention depends on the specific compound, and on the condition to be treated; the selection of the appropriate dose is well within the knowledge of the skilled artisan.
The ophthalmic formulations of the present invention are conveniently packaged in forms suitable for metered application, such as in containers equipped with a dropper, to facilitate application to the eye. Containers suitable for dropwise application are usually made of suitable inert, non-toxic plastic material, and generally contain between about 0.5 and about 15 ml solution. One package may contain one or more unit doses.
Especially preservative-free solutions are often formulated in non-resealable containers containing up to about ten, preferably up to about five unit doses, where a typical unit dose is from one to about 8 drops, preferably one to about 3 drops. The volume of one drop usually is about 20-35 μl.
The compounds disclosed herein for use in the method of this invention, i.e. the treatment of glaucoma or elevated intraocular pressure, may also be used in combination with other drugs useful for the treatment of glaucoma or elevated intraocular pressure.
For the treatment of glaucoma or elevated intraocular pressure, combination treatment with the following classes of drugs are contemplated:
β-Blockers (or β-adrenergic antagonists) including carteolol, levobunolol, metipranolol, timolol hemihydrate, timolol maleate, β1-selective antagonists such as betaxolol, and the like, or pharmaceutically acceptable salts or prodrugs thereof; Adrenergic Agonists including non-selective adrenergic agonists such as epinephrine borate, epinephrine hydrochloride, and dipivefrin, and the like, or pharmaceutically acceptable salts or prodrugs thereof; and α 2 -selective adrenergic agonists such as apraclonidine, brimonidine, and the like, or pharmaceutically acceptable salts or prodrugs thereof; Carbonic Anhydrase Inhibitors including acetazolamide, dichlorphenamide, methazolamide, brinzolamide, dorzolamide, and the like, or pharmaceutically acceptable salts or prodrugs thereof; Cholinergic Agonists including direct acting cholinergic agonists such as carbachol, pilocarpine hydrochloride, pilocarpine nitrate, pilocarpine, and the like, or pharmaceutically acceptable salts or prodrugs thereof; chlolinesterase inhibitors such as demecarium, echothiophate, physostigmine, and the like, or pharmaceutically acceptable salts or prodrugs thereof; Glutamate Antagonists such as memantine, amantadine, rimantadine, nitroglycerin, dextrophan, detromethorphan, CGS-19755, dihydropyridines, verapamil, emopamil, benzothiazepines, bepridil, diphenylbutylpiperidines, diphenylpiperazines, HOE 166 and related drugs, fluspirilene, eliprodil, ifenprodil, CP-101,606, tibalosine, 2309BT, and 840S, flunarizine, nicardipine, nifedimpine, nimodipine, barnidipine, lidoflazine, prenylamine lactate, amiloride, and the like, or pharmaceutically acceptable salts or prodrugs thereof; Prostamides such as bimatoprost, or pharmaceutically acceptable salts or prodrugs thereof; and Prostaglandins including travoprost, UFO-21, chloprostenol, fluprostenol, 13,14-dihydro-chloprostenol, isopropyl unoprostone, latanoprost and the like.
The invention is further illustrated by the following non-limiting Examples.
EXAMPLE 1
Intraocular Pressure
Intraocular pressure was measured by applanation pneumatonometry in conscious animals. The test compound was administered topically to one eye while vehicle was given to the fellow eye in a masked fashion. Laser-induced unilaterally ocular hypertensive Cynomolgus monkeys (females) were dosed once and the IOP was measured over the course of 24 hours.
The results are shown in the Table, below wherein the stars indicating the potency of the compound. That is, one star indicates no potency, three stars indicates a very potent compound.
Example No.
Efficacy
Vehicle
*
5
***
16 (c) Tetrahydropyridine derivative
**
20 Piperidinedione derivative
***
9 (b) Cyclohexane derivative
***
EXAMPLE 2
Determination of Abnormal Cannabidiol Activity
Abnormal Cannabidiol receptor activity may be measured in accordance with the procedure disclosed in (Wagner J A et al., Hypertension 33 [part II], 429 (1999); Járai Z et al., PNAS 96, 14136 (1999), which is hereby incorporated by reference in its entirety.
When measured according to this assay all of the compounds of the Examples, below, are found to be active.
Experimental Details for Synthesis of Abnormal Cannabidiols
General Route
EXAMPLE 3
Synthesis of 4-(6-Isopropenyl-3-methylcyclohex-2-enyl)-5-methylbenzene-1,3-diol
(4R)-1-Methyl-4-isopropenylcyclohex-2-ene-1-ol (300 mg, 2 mmoles) was dissolved in toluene (20 ml) and 5-methylresorcinol (248 mg, 2 mmoles) was added in diethyl ether (5 ml). Oxalic acid dihydrate (252 mg, 2 mmoles) was added and the reaction mixture heated with stirring at 80° for 5 hours. The reaction mixture was allowed to cool and diluted with diethyl ether (30 ml). The ether solution washed twice with aqueous sodium bicarbonate and dried over anhydrous magnesium sulphate. The solvents were evaporated under reduced pressure to give the crude product as a brown oil (800 mg). The product was purified using a silica column eluted with ethyl acetate:isohexane 1:9 going to ethyl acetate:isohexane 2:8.
The product was isolated as a yellow gum (106 mg)
1 H NMR (300 MHz, CDCl 3 ) 6.2 (M, 2H), 6.1 (S, 1H), 5.55 (M, 1H), 4.7 (M, 1H), 4.55 (S, 1H), 4.5 (M, 1H), 3.55 (M, 1H), 2.5 (M, 1H), 2.2 (M, 2H), 2.15 (S, 3H), 1.85 (M, 2H), 1.8 (S, 3H), 1.6 (S, 3H)
The reaction product is recovered using a silica column eluted with ethyl acetate:isohexane 1:9 going to ethyl acetate:isohexane 2:8.
The product was isolated as a yellow gum (106 mg)
1 H NMR (300 MHz, CDCl 3 ) 6.2 (M, 2H), 6.1 (S, 1H), 5.55 (M, 1H), 4.7 (M, 1H), 4.55 (S, 1H), 4.5 (M, 1H), 3.55 (M, 1H), 2.5 (M, 1H), 2.2 (M, 2H), 2.15 (S, 3H), 1.85 (M, 2H), 1.8 (S, 3H), 1.6 (S, 3H)
Also prepared in a similar manner were:
EXAMPLE 4
4-(6-Isopropenyl-3-methylcyclohex-2-enyl)benzene-1,3-diol
1 H NMR (300 MHz, CDCl 3 ) 6.8 (D, 1H J=8 Hz), 6.35 (M, 1H), 6.3 (M, 1H), 5.6 (S, 1H), 5.5 (S, 1H), 4.7 (M, 1H), 3.35 (M, 1H), 2.3 (M, 1H), 2.1 (M, 2H), 1.8 (M, 2H), 1.85 (S, 3H), 1.6 (S, 3H)
EXAMPLE 5
5-Chloro-4-(6-Isopropenyl-3-methylcyclohex-2-enyl)benzene-1,3-diol
1 H NMR (300 MHz, CDCl 3 ) 6.4 (M, 1H), 6.3 (M, 1H), 6.25 (S, 1H), 5.6 (M, 1H), 4.7 (brS, 1H), 4.65 (M, 1H), 4.4 (M, 1H), 4.0 (M, 1H), 2.5 (M, 1H), 2.25 (M, 1H), 2.15 (M, 1H), 1.85 (M, 2H), 1.8 (S, 3H), 1.6 (S, 3H)
EXAMPLE 6
4-(6-Isopropenyl-3-methylcyclohex-2-enyl)-5-methoxybenzene-1,3-diol
1 H NMR (300 MHz, CDCl 3 ) 6.15 (brS, 1H), 6.0 (M, 2H), 5.6 (M, 1H), 4.65 (brS, 1H), 4.5 (M, 1H), 4.35 (M, 1H), 3.95 (M, 1H), 3.7 (S, 3H), 2.4 (M, 1H), 2.25 (1H, M), 2.1 (M, 1H), 1.8 (M, 2H), 1.8 (S, 3H), 1.65 (S, 3H)
EXAMPLE 7
2-(6-Isopropenyl-3-methylcyclohex-2-enyl)-5-methoxybenzene-1,3-diol
1 H NMR (300 MHz, CDCl 3 ) 6.0 (brS, 2H), 5.55 (M, 1H), 4.7 (M, 1H), 4.6 (M, 1H), 3.8 (M, 1H), 3.75 (S, 3H), 2.4 (M, 1H), 2.2 (M, 1H), 2.1 (M, 1H), 1.8 (S, 3H), 1.8 (M, 2H)
EXAMPLE 8(a)
Synthesis of 6-Chloro-4-(6-Isopropenyl-3-methylcyclohex-2-enyl)benzene-1,3-diol
4-Chlororesorcinol (350 mg, 2.4 mmoles) was dissolved in toluene (30 ml) and diethyl ether (20 ml) and p-toluenesulphonic acid (91 mg, 0.48 mmoles) was added.
(4R)-1-Methyl-4-isopropenylcyclohex-2-ene-1-ol (500 mg, 3 mmoles) in toluene (10 ml) was added and the reaction mixture was stirred at room temperature for 6 hours. Diluted with diethyl ether (30 ml) and washed twice with aqueous sodium bicarbonate. Dried over anhydrous magnesium sulphate and the solvent was evaporated under reduced pressure to give a yellow gum (800 mg). Purified using a silica column eluted with ethyl acetate:isohexane 9:1 going to ethyl acetate:isohexane 8:2. The product was isolated as a yellow gum (95 mg)
1 H NMR (300 MHz, CDCl 3 ) 6.9 (S, 1H), 6.5 (S, 1H), 5.5 (S, 1H), 5.45 (M, 1H), 5.35 (S, 1H), 4.7 (M, 1H), 4.6 (M, 1H), 3.35 (M, 1H), 2.2 (M, 3H), 1.8 (M, 3H), 1.75 (M, 2H), 1.6 (S, 3H)
Examples 8(b) and 8(c) are made by the same method as example 8(a) using cis-verbenol instead of (4R)-1-Methyl-4-isoprenylcyclohex-2-ene-1-ol.
EXAMPLE 8(b)
5-Methyl-4-(4,6,6-trimethyl-bicyclo[3.1.1]hept-3-en-2-yl)benzene-1,3-diol
1 H NMR (300 MHz, CDCl 3 ) 7.35 (brs, 1H), 6.25 (m, 1H), 6.2 (m, 1H), 5.7 (m, 1H), 4.75 (brs, 1H), 3.7 (m, 1H), 2.35 (m, 1H), 2.2 (s, 3H), 2.15 (m, 1H), 1.9 (S, 3H), 1.6 (d, 1H), 1.35 (s, 3H), 1.0 (s, 3H)
EXAMPLE 8(c)
5-Chloro-4-(4,6,6-trimethyl-bicyclo[3.1.1]hept-3-en-2-yl)benzene-1,3-diol
1 H NMR (300 MHz, CDCl 3 ) 7.55 (s, 1H), 6.5 (m, 1H), 6.25 (m, 1H), 5.7 (m, 1H), 5.45 (s, 1H), 4.0 (m, 1H), 2.3 (m, 1H), 2.2 (m, 1H), 1.9 (S, 3H), 1.5 (d, 1H), 1.35 (s, 3H), 1.0 (s, 3H)
EXAMPLE 9(a)
Synthesis of 4-Cyclohexylbenzene-1,3-diol
This compound was prepared as described in JACS, 1953, 2341.
Resorcinol (2.2 g, 0.02 moles) was mixed with cyclohexanol (1 g, 0.01 moles) and zinc (II) chloride (0.48 g, 0.0035 moles) and the reaction mixture heated to 150° with stirring. After heating 2 hours, the reaction mixture was allowed to cool and then dissolved in ethyl acetate. Washed with water and dried over anhydrous magnesium sulphate. The solvent was evaporated to give a brown oil (3.0 g). Excess resorcinol was evaporated by heating in a Kugelrohr oven under reduced pressure (200°, 2 mmHg). Purified using a silica column eluted with ethyl acetate: isohexane 2:8 to give the product as a yellow oil (0.5 g). Trituration with isohexane gave the product as a white solid (0.2 g).
EXAMPLE 9(b)
5-Chloro-4-cyclohexylbenzene-1,3-diol
Example 9(b) was made by the same method as Example 9(a).
1 H NMR (300 MHz, CDCl 3 ) 7.0 (D, 1H J=8 Hz), 6.4 (M, 1H), 6.3 (M, 1H), 4.7 (S, 1H), 4.55 (S, 1H), 2.7 (M, 1H), 1.8 (M, 5H), 1.4 (M, 5H)
EXAMPLE 10
Synthesis of 4R-Isopropenyl-1-methylcyclohex-2-enol
The synthesis of 4R-Isopropenyl-1-methylcyclohex-2-enol was carried out as described in WO2004096740.
EXAMPLE 11
4-Isopropenyl-1-methyl-2-morpholin-4-yl-cyclohexanol
(+)-Limonene oxide (13.2 g, 0.087 moles) was dissolved in ethanol (40 ml) and lithium chloride (5.9 g, 0.14 moles) was added with stirring. Morpholine (11.4 g, 0.13 moles) was added and the reaction mixture was heated at 60° for 48 hours. The solvent was evaporated under reduced pressure and the residue taken up in dichloromethane. Washed with water. Extracted into 2M hydrochloric acid and washed with dichloromethane. Basified to pH 10 by addition of 2M sodium hydroxide. Extracted with diethyl ether and washed with water. Dried over anhydrous magnesium sulphate and evaporated the solvent under reduced pressure to give the product as a yellow oil (10.3 g)
1 H NMR (300 MHz, CDCl 3 ) 4.95 (M, 1H), 4.85 (M, 1H), 3.7 (M, 4H), 2.75 (M, 2H), 2.5 (M, 4H), 2.1 (M, 1H), 1.95 (M, 1H), 1.75 (S, 3H), 1.6 (M, 4H), 1.2 (S, 3H)
EXAMPLE 12
4-Isopropenyl-1-methyl-2-(4-oxy-morpholin-4-yl)-cyclohexanol
4-Isopropenyl-1-methyl-2-morpholin-4-yl-cyclohexanol (17.7 g, 0.074 moles) was dissolved in ethanol (100 ml) and 35% hydrogen peroxide (37 ml, 0.325 moles) was added. Heated with stirring at 50° for 6 hours. 5% palladium on carbon (100 mg) was added in order to decompose the excess peroxide. Stirred at room temperature for 3 hours. (Peroxide test papers gave a negative result.)
Filtered through a pad of HiFlo to remove the palladium on carbon and the solvent was evaporated under reduced pressure to give the product as a yellow oil (22.2 g).
1 H NMR (300 MHz, CDCl 3 ) 5.5 (M, 1H), 4.85 (M, 1H), 4.5 (M, 2H), 3.7 (M, 4H), 3.4 (M, 3H), 2.95 (M, 1H), 2.65 (M, 1H), 2.25 (M, 1H), 2.0 (M, 1H), 1.85 (M, 1H), 1.75 (M, 1H), 1.75 (S, 3H), 1.55 (M, 1H), 1.55 S, 3H)
EXAMPLE 13
4R-Isopropenyl-1-methylcyclohex-2-enol
4-Isopropenyl-1-methyl-2-morpholin-4-yl-cyclohexanol (4.6 g, 0.018 moles) was dissolved in toluene (80 ml) and silica (1.1 g) was added. The reaction mixture was heated to reflux with stirring. Water generated in the reaction was removed using Dean and Stark apparatus. After refluxing overnight, the silica was removed by filtration and the filtrate evaporated under reduced pressure to give a brown oil (4.0 g). Dissolved in dichloromethane and washed with 2M hydrochloric acid. Washed with water and dried over anhydrous magnesium sulphate. The solvent was removed by evaporation under reduced pressure to give the product as a brown oil (1.3 g).
1 H NMR (300 MHz, CDCl 3 ) 5.7 (M, 2H), 4.8 (M, 2H), 2.7 (M, 1H), 1.8 (M, 2H), 1.75 (S, 3H), 1.65 (M, 2H), 1.3 (S, 3H)
Experimental Details for Synthesis of Tetrahydropyridines
EXAMPLE 14
Preparation of 2-(2,4-Dimethoxyphenyl)-1,4-dimethyl-1,2-dihydropyridine (4)
To a stirred solution of 2,4-dimethoxybromobenzene (1) (0.5 g, 2.3 mmol) in diethyl ether (10 ml) cooled at −78° C. under nitrogen was added a solution of n-butyl lithium (1.0 ml, 2.5 mmol of 2.5M solution in hexane) drop wise. The mixture was stirred at −78° C. for 2 hours and then 1,4-dimethylpyridinium iodide (2) (0.54 g, 2.5 mmol) was added as a solid. The resultant mixture was allowed to warm to room temperature and stirred at room temperature for 18 hours. The mixture was diluted with water (20 ml) and extracted with diethyl ether (2×15 ml). The combined organic extracts were dried over anhydrous magnesium sulphate, filtered and evaporated to yield 2-(2,4-dimethoxyphenyl)-1,4-dimethyl-1,2-dihydropyridine (4) (0.5 g, 93%) as a brown oil, 1 H NMR CDCl 3 ??1.7 (s, 3H), 2.7 (s, 3H), 3.8 (s, 6H), 4.45 (dd, 1H, J=2.7) 4.85 (m, 1H), 5.4 (d, 1H, J=4), 6.05 (d, 1H, J=7), 6.45 (d, 1H, J=3), 6.55 (m, 1H), 7.5 (d, 1H, J=9).
By proceeding in a similar manner starting from 2,4-dimethoxybromobenzene (1) and 1-isopropyl-4-methylpyridinium iodide (3), 2-(2,4-dimethoxyphenyl)-1-isopropyl-4-methyl-1,2-dihydropyidine (5) was prepared, 1 H NMR CDCl 3 ? (d, 6H J=7), 1.7 (s, 3H), 3.15 (m, 1H), 3.7 (s, 6H), 4.5 (d, 1H J=8), 4.8 (m, 1H), 5.5 (5, 1H J=5), 6.3 (d, 1H J=7), 6.45 (d, 1H J=2), 6.55 (m, 1H), 7.55 (d, 1H J=8).
EXAMPLE 15
Preparation of 6-(2,4-Dimethoxyphenyl)-1,4-dimethyl-1,2,3,6-tetrahydro-pyridine (6)
To a stirred solution of 2-(2,4-dimethoxyphenyl)-1,4-dimethyl-1,2-dihydropyridine(4) (0.48 g, 2.06 mmol) in methanol (5 ml) at room temperature was added sodium borohydride (98 mg, 2.51 mmol), gas evolution commenced immediately, the resulting mixture was stirred for 3 hours. At this time the solvent was evaporated and the residue suspended in water (5 ml) and extracted with ethyl acetate (2×10 ml). The organic extract was then extracted with 2M hydrochloric acid (2×15 ml). The aqueous layer was basified with 2M sodium hydroxide and extracted with ethyl acetate (2×20 ml), the organic extract was dried over anhydrous magnesium sulphate, filtered and evaporated to yield 6-(2,4-dimethoxyphenyl)-1,4-dimethyl-1,2,3,6-tetrahydropyridine (6) (350 mg, 73%) as a yellow oil, 1 H NMR CDCl 3 δ?1.55 (s, 3H), 1.9 (m, 1H), 2.2 (s, 3H), 2.5 (m, 2H), 2.95 (m, 1H), 3.8 (s, 6H), 4.1 (m, 1H), 5.2 (m, 1H), 6.5 (m, 2H), 7.3 (d, 1H J=4).
By proceeding in a similar manner starting from 2-(2,4-dimethoxyphenyl)-1-isopropyl-4-methyl-1,2-dihydropyidine (5), 6-(2,4-dimethoxyphenyl)-1-isopropyl-4-methyl-1,2,3,6-tetrahydropyridine (7) was prepared, 1 H NMR CDCl 3 δ 0.95 (d, 3H J=6), 1.05 (d, 3H J=6), 1.7 (s, 3H), 1.9 (m, 1H), 2.5 (m, 1H), 2.85 (m, 1H), 3.0 (m, 1H), 3.8 (s, 6H), 4.6 (s, 1H), 5.2 (s, 1H), 6.45 (d, 1H J=3), 6.5 (dd, 1H J=3.8), 7.4 (d, 1H J=8).
EXAMPLE 16(a)
Preparation 4-(1,4-Dimethyl-1,2,5,6-tetrahydropyridin-2-yl)-benzene-1,3-diol (8)
To a stirred solution of 6-(2,4-dimethoxyphenyl)-1,4-dimethyl-1,2,3,6-tetrahydro-pyridine (6) (300 mg, 1.27 mmol) in dichloromethane (20 ml) cooled at 0° C. under nitrogen was added boron tribromide (3.1 ml, 3.18 mmol of 1.0M solution in dichloromethane), the resultant dark solution was allowed to warm to room temperature and stirred for 1 hour. The solution was poured onto ice and basified with sodium bicarbonate. The layers were separated and the aqueous layer was extracted with dichloromethane (20 ml), the combined organic layers were dried over anhydrous magnesium sulphate, filtered and evaporated to a gum (200 mg). The material was purified on a 10 g silica cartridge eluting with methanol/dichloromethane/ammonia (7:92:1) to yield 4-(1,4-dimethyl-1,2,5,6-tetrahydropyridin-2-yl)-benzene-1,3-diol (8) (93 mg, 35%) as a gum, 1 H NMR D6-acetone ??1.67 (s, 3H), 1.97 (m, 1H), 2.3 (s, 3H), 2.42 (m, 1H), 2.74 (m, 1H), 3.08 (m, 1H), 3.74 (s, 1H), 5.15 (s, 1H), 6.2 (d, 1H J=2), 6.27 (dd, 1H J=2.8), 6.82 (d, 1H J=8), 9.4 (bs, 2H).
EXAMPLE 16(b)
By proceeding in a similar manner starting from 6-(2,4-dimethoxyphenyl)-1-isopropyl-4-methyl-1,2,3,6-tetrahydropyridine (7), 4-(1-isopropyl-4-methyl-1,2,5,6-tetra-hydropyridin-2-yl)-benzene-1,3-diol (9) was prepared, NMR D6-acetone δ 0.81 (d, 3H J=7), 0.98 (d, 3H J=7), 1.52 (s, 3H), 1.84 (m, 1H), 2.15 (m, 1H), 2.29 (m, 1H), 2.94 (m, 2H), 4.09 (s, 1H), 4.97 (s, 1H), 6.05 (d, 1H J=3), 6.11 (dd, J=3.8), 6.68 (d, J=8), 9.6 (bs, 2H).
EXAMPLE 16(c)
By proceeding in a similar manner 4-(1-isopropyl-4-methyl-1,2,5,6-tetra-hydropyridin-2-yl) -5-methylbenzene-1,3-diol (10) was prepared, NMR CDCl 3 δ 1.0 (d, 3H), 1.15 (d, 3H), 1.7 (s, 3H), 1.95 (m, 1H), 2.2 (s, 3H), 2.4 (m, 2H), 3.1 (m, 2H), 4.55 (m, 1H), 5.15 (m, 1H), 6.2 (m, 2H)
EXAMPLE 17
Preparation of 1-Isopropyl-4-methylpyridinium iodide (3)
To a stirred solution of 4-picoline (2.5 g, 26.8 mmol) in acetonitrile (50 ml) was added isopropyl iodide (9.1 g, 53.6 mmol) drop wise, the resultant mixture was heated at 90° C. for 24 hours. After cooling the solvent was evaporated to give a red solid which on trituration with ethyl acetate yielded 1-isopropyl-4-methylpyridinium iodide (6.01 g, 85%) as a cream solid, 1 H NMR D6-DMSO δ?1.6 (d, 6H, J=7), 2.6 (s, 3H), 4.95 (m, 1H), 8.0 (d, 2H J=6), 9.05 (d, 2H J=6).
Experimental Details for Preparation of Piperidine-2,4-diones
These compounds may also be prepared as described in J. Chem. Soc. Perkin I 1996, 2041-2050.
EXAMPLE 18
Preparation of Ethyl 1-cyclohexyl-piperidine-2,4-dione-3-carboxylate
N-Cyclohexyl-N-(2-ethoxycarbonyl-ethyl)-malonamic acid ethyl ester (5.40 g, 17.2 mmol) was heated with sodium ethoxide (2.34 g, 3.44 mmol) in refluxing ethanol (100 ml) for 3 hours. The cooled solution was concentrated, water (100 ml) was added and the solution washed with ether then isohexane. It was acidified with c. sulphuric acid to pH 2. The oily precipitate was extracted into dichloromethane, wahed with brine, dried (MgSO 4 ) and concentrated to a yellow oil weighing 3.6 g (67%).
EXAMPLE 19
Preparation of 1-Cyclohexyl-piperidine-2,4-dione
1-Cyclohexyl-2,4-dioxo-piperidine-3-carboxylic acid ethyl ester (3.1 g, 11.6 mmol) was heated with water (0.25 ml, 13.9 mmol) in nitromethane (30 ml) at 95° C. for 1 hour. The solution was concentrated to give an off-white solid weighing 2.3 g (93%). A sample was recrystallised from toluene.
1 H NMR (CDCl 3 , ppm) δ 1.05-1.90 (m, 10H), 2.56 (t, 2H), 3.38 (s, 2H), 3.55 (t, 2H), 4.50 (m, 1H).
Also prepared in a similar manner was
EXAMPLE 20
Preparation of 1-Cyclohexyl-6-methylpiperidine-2,4-dione
1 H NMR (CDCl 3 , ppm) δ 1.05-1.95 (m, 13H), 2.56 (m, 2H), 3.35 (m, 2H), 3.96 (m, 1H), 4.50 (m, 1H).
It is apparent to one of ordinary skill in the art that different pharmaceutical compositions may be prepared and used with substantially the same results. That is, other Abnormal Cannabidiols will effectively lower intraocular pressure in animals and are within the scope of the present invention. Also, the novel compounds of the present invention may be used in a method of providing neuroprotection to the eye of a mammal in a similar manner to the abnormal Cannabidiols of Published U.S. Patent Application 2005/0282912. | The present invention provides a method of treating glaucoma or ocular hypertension which comprises applying to the eye of a person in need thereof an amount sufficient to treat glaucoma or ocular hypertension of a compound of formula I
wherein Y, Q, Z, R, R 1 and R 2 are as defined in the specification.
The present invention further comprises pharmaceutical compositions, e.g. ophthalmic compositions, including said compound of formula I. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention pertains to borehole drilling apparatus and specifically to that part of a drill string known in the industry as a stabilizer.
2. Description of the Prior Art
Stabilizers, sometimes referred to as drill collar stabilizers or as drill stem stabilizers, have been employed in earth boring operations for the petroleum industries to centralize the drill stem in the borehole, usually especially in the drill collar section at a distance of from 100 feet to 1000 feet above the drill bit. The purposes of a stabilizer are to (1) help control hole angle direction, (2) prevent the bit from drifting laterally, which would result in undesirable dog-legs and ledges, and (3) improve bit performance by forcing the bit to centrally rotate about its axis so as to provide substantially equal force loading on all three drill bit cones. In addition, stabilizers also may be used to provide a reaming function for undersized or irregularly shaped boreholes providing the formation is not too hard.
Stabilizers are categorized in the industry as rotating stabilizers and as non-rotating stabilizers. A rotating stabilizer includes wall-contacting members that rotationally track along the wall of the borehole as the drill string is turned. On the other hand, non-rotating stabilizers, one type of which is also referred to as sleeve-type stabilizers, do not rotate as the drill string is turned, its wall-contacting members merely moving around the wall of the borehole as the drill string is rotated and lowered or raised.
The contacting members of a rotating type of stabilizer, which is the type of stabilizer described herein, are subjected to the various forces attendant to the entire drill string, including thrust forces, fretting forces, and the forces applied to the drill string as a result of the drill string manipulations, the conditions of the bore, and the fluid conditions internal and external to the drill string.
Various rotating types of stabilizers include mechanisms for connecting and detaching the wear elements to provide for their replacements. Such connectable and detachable mechanisms include various slot and groove connections, cap screw connections, tapered wedging connections and combinations of the above. However, one of the most popular types of stabilizer of the rotating variety is known as the "welded-blade" stabilizer. Its popularity stems from the fact that there are no connectable mechanisms between the parts other than the permanent welds that affix the wear element, commonly known as the blade, to the drill string member.
Welded blade stabilizers in the prior art are typified by the structures shown in Ortloff et al., U.S. Pat. No. 3,263,274. The wear pads shown in the Ortloff structures are welded to the body of the tool joint; however, it should be recognized that tool joints are typically made of alloy steel which are difficult to weld in reliable fashion, particularly under field environment. That is, welding thereon can only be reliably performed in a controlled environment where the alloy steel is heated and cooled quite slowly and in a clean environmental surroundings. When welding of this type is attempted in conditions other than such a controlled environment, the alloy steel cools too quickly and results in cracking of the weld. Even when welds are made under controlled conditions, some damage is done to the alloy structural member. This damage is accumulative and irreversible. After many replacements are made the lasting damage by itself may be enough to cause the occurrence of cracks.
There are also structures in the prior art, such as shown in Creighton, U.S. Pat. No. 2,288,124, that discloses stabilizer elements held within sleeves which are, in turn, welded to the tubular body. Although there are many different structures shown in Creighton, one of which has elements welded to the surface of the protector body sleeve (facing 29 welded to body 10c in FIG. 8 of Creighton), there is no showing in Creighton of the use of a sleeve which is particularly suited for affixing weldable wear pads thereto.
Therefore, it is a feature of the present invention to provide a stabilizer having wear elements that are reliably affixable by welding under field conditions.
It is another feature of the present invention to provide a stabilizer with a sleeve or other suitable arrangement to permit wear-element affixing to the stabilizer tool body by welding, rather than by clamping, snapping or other releasable means.
SUMMARY OF THE INVENTION
The weldable blade stabilizer embodiments of the invention herein disclosed include replaceable, normally hard-faced wear elements for contacting the surface of the borehole when the stabilizer is in use, which elements are affixed to the stabilizer drill string memeber by welding to a readily weldable surface. In some embodiments this surface is the surface of a sleeve or partial sleeve made of low carbon steel. In other embodiments, the easily weldable surface is built-up weld metal.
BRIEF DESCRIPTION OF THE DRAWINGS
So that the manner in which the above-recited features, advantages and objects of the invention, as well as others which will become apparent, are attained 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, which drawings form a part of this specification. It is to be noted, however, that the appended drawings illustrate only preferred embodiments of the invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments.
In the Drawings
FIG. 1 is a partial longitudinal cross-sectional view of a welded blade stabilizer in accordance with a preferred embodiment of the present invention.
FIG. 2 is a cross-sectional view taken at 2--2 of FIG. 1.
FIG. 3 is a partial longitudinal cross-sectional view of a segment of another embodiment of a welded blade stabilizer in accordance with the present invention.
FIG. 4 is a partial longitudinal cross-sectional view of a welded blade stabilizer in accordance with yet another embodiment of the present invention.
FIG. 5 is a cross-sectional view taken at 5--5 of FIG. 4.
FIG. 6 is a partial longitudinal cross-sectional view of a segment of still another embodiment of a welded blade stabilizer in accordance with the present invention.
FIG. 7 is a partial longitudinal cross-sectional view of a segment of yet another embodiment of a welded blade stabilizer in accordance with the present invention.
DESCRIPTION OF PREFERRED EMBODIMENTS
Now referring to the drawings, and first to FIG. 1, a stabilizer in accordance with the present invention is shown in longitudinal cross-section. Body 1 of the illustrated stabilizer tool is threaded for suitable connection to adjoining members cooperatively threaded therewith in the drill string. As illustrated, pin end 10 of the drill string member is toward the bottom and box end 12 is toward the top. The body of the stabilizer includes a fluid circulation hole 14 therethrough and is normally screwed into the drill string in connection with the collar section. Generally, such a section is located 100-1000 feet above the bit. However, a stabilizer tool may be located in other and additional locations in the string. Nothing herein limits the location of the stabilizer to any particular location.
The wear elements or blades of a stabilizer extend beyond the periphery of the tool body to which they are attached and bear against the inside surface of the borehole in which the tool is used. The blades are spaced apart from one another to permit fluid circulation therebetween. There is a shoulder 16 just below the location where the blades are to be affixed. The tool circumference above below this shoulder is enlarged with respect to the circumference below this shoulder. A short sleeve 18 of easily weldable material, typically a low carbon steel, is slipped over the bottom or pin end of the tool and positioned adjacent shoulder 16. The inside diameter of the sleeve fits snugly around the external circumference of body 1 at this position. Such a sleeve can be shrunk on by a preheating process or can be made to close tolerance for its snug fitting. Sleeve 18 is then carefully welded in place by weld bead 20.
It should be noted that body 1 of the stabilizer is made of a high strength alloy steel. This steel typically includes, in addition to carbon, one or more of the following alloy constituents: manganese, chromium, nickle, molybdenum, although other constituents are also sometimes employed. In all events, when such metal is welded, the temperature must be carefully controlled to prevent the weld from cracking when it cools. Also, the environment must include an inert gas atmosphere and be kept as pure or clean as possible. If contaminates get into the weld, this will cause cracks to appear, as well.
On the other hand, low carbon steel alloys do not tend to crack when quenched or cooled rapidly. Furthermore, high quality welds can be made without the rigid controls required for high strength steels. Although more material is usually required for a comparably used structure to make it strong enough for the same service conditions, welds in such materials tend to be free of cracks and the steel itself does not undergo heat treatment such as with the high strength alloy steels previously mentioned. By making sleeve 10 of such material it is "easily weldable" as contrasted to the steel of body 1.
To complete the assembly shown in FIG. 1, a long sleeve 22, having an inside diameter for snugly fitting over body 1 adjacent short sleeve 18, is slipped over the body into the position shown. This sleeve includes a plurality of wear elements or blades 24 spaced about the periphery. These blades are typically beveled at their leading and trailing edges, are hard surfaced and may be on hole bore contact surfaces for maximum wear qualities. The abutting surfaces of long sleeve 22 and short sleeve 18 are then welded together by weld bead 26. It should be noted that weld bead 26 does not penetrate the thickness of either sleeve 22 or sleeve 18 to a depth where the weld reaches into or even touches the surface of body 1. Therefore, all of the welding takes place in easily weldable material which does not require welding under closely controlled temperature and clean air conditions.
When one or more of the wear element surfaces of sleeve 22 becomes worn, damaged or otherwise it is indicated that they should be replaced, weld 26 is broken to release the junction and sleeve 22, including the damaged or worn wear elements 24, is removed. A new sleeve 22 with new or reworked elements is replaced and a new weld 26 is made, as previously described. If the wear elements on the removed collar can be reworked or replaced, this can now be done in a clean and temperature-controlled environment without taking the drill string member with its new sleeve out of service.
Alternatively to the sleeves shown in FIG. 1, either or both sleeves 18 and 22 may be partial sleeves or made up of two or more partial sleeves welded together.
FIG. 3 shows an alternate scheme for providing a suitable easily weldable material for affixing long sleeve 22 thereto. In this embodiment, an effective narrow sleeve is made up by building up weld material 18' while the drill string member is in a controlled environment, as previously described. Again, in affixing a good or new sleeve 22 in place, weld 26 does not completely penetrate either sleeve 22 or weld metal 18' so as to contact the surface of body 1 therebeneath.
FIG. 4 illustrates yet another embodiment of the present invention. In this embodiment a single long collar or sleeve 28 is employed in connection with a drill string member 1 of similar configuration to that previously described. Sleeve 28 is longer than the longitudinal length of wear elements 30 to be attached thereto and surrounds and fits so that its upper end is adjacent shoulder 16 of drill string member 1. As with sleeve 22 of the FIG. 1 embodiment, sleeve 28 may be either a closely fitted sleeve or heat shrunk thereon. In fact, it also may be made up of two or more separate pieces which are joined together. In all events, sleeve 28 is secured to drill string member 1 by weld bead 32 at its upper end (adjacent shoulder 16) and by weld bead 34 at its lower end. These welds are each made in a clean and temperature and inert-gas controlled environment to protect against the creation of weld cracks.
Separate wear elements 30 are attached about the periphery of sleeve 28 at an appropriate angle, as shown, via weld beads 36 along the elongated sides of these wear elements. It should be noted that these wear elements are elongated and bevelled at both their leading and trailing edges and are hard faced or surfaced. The welds are made to sleeve 28 but not through them to the underlying surface of member 1. As with the other embodiments previously described, the material of sleeve 28 is easily weldable in a field environment and the welds, even when made in such environment, are not subject to cracking.
When a wear element 30 is damaged or becomes excessively worn, welds 36 are machined or torch-cut away to remove the used element. A new or reworked element 30 is then placed in position and new welds 36 are made, as shown. If only one of the blades needs replacement, then only that blade is replaced.
FIG. 6 is an alternative embodiment to that shown in FIG. 4. In this embodiment, an effective sleeve 28' is built up underneath the area where wear elements 30 are to be attached. Sleeve 28 (or 28') is sufficiently thick so that weld 24 does not penetrate and damage underlying body 1. Removal and replacement of an old element is accomplished in the same manner as previously discussed. It may been seen that the replacement welds are made in easily weldable material and, therefore, there is no need to have a closely controlled environment.
It may be seen that sleeve 28' discussed above has been illustrated and described as being entirely around the drill string member. However, a sleeve that only partially surrounds the member and is controllably welded thereto to form an underlying base of easily weldable material for the wear elements to be attached, is suitable as an alternative to that which is described above.
The discussion above pertains to embodiments of the invention including a sleeve or partial sleeve for welding thereto the replaceable wear elements or wear element assembly. FIG. 7 shows yet another embodiment of the invention which has advantages of attaching replaceable wear elements, even under closely controlled conditions. The view is shown a longitudinal cross section of the blade portion thereof.
Cracks which occur in welded blade stabilizer bodies are often caused by damage of the high strength body material when welding blades or wear elements to the body. When used or damaged elements are removed and new wear elements are welded to the previously welded areas, the damage is accumulative and irreversible.
The stabilizer's body is subjected to bending stresses in service. Stresses in the body are greatest close to the ends of the wear elements. This stress concentration effect is caused by the change of stiffness where the body is no longer supported by the wear elements. Hence, most cracks occur close to the end of the wear elements.
The embodiments shown in FIG. 7 provides a section of built-up weld material 40 in a reduced portion of the stabilizer body just below shoulder 16. This section, which equates with a section of a sleeve as discussed with the previous embodiments, underlies the top end of the wear element and is only built-up to the extent that it restores the original dimension of the stabilizer body. The wear element lies snugly on top thereof, as shown.
In like fashion, another section 42 of built-up weld material in a reduced portion of the stabilizer body lies just above shoulder 17, which is similar to shoulder 16 at the top. This section underlies the bottom end of the wear element and also is only built-up to the extent that it restores the original dimension of the stabilizer body. There is a large area of stabilizer body underneath the wear element between the built-up material sections. It also may be noted that the body of the stabilizer can be reduced or not at a distance above shoulder 16 and/or below shoulder 17, as desired.
The structure just described will permit the wear elements at the factory or otherwise under controlled environmental conditions to be welded to the high strength material of the body of the stabilizer by elongate weld beads in the area between sections 40 and 42 and then to be conveniently welded by extension of these beads in these sections 40 and 42 of easily weldable material. Therefore, this embodiment provides a way of reducing body cracking where the stresses mostly occur. Although this structure will not eliminate the need for pre-heating before welding and post-heating afterward because the center section of the wear element is welded to the body material, the construction still may be preferred because of the cost advantages in manufacturing and because of the elimination of crack problems where most cracks occur.
Although numerous embodiments have been shown and described, it will be understood that the invention is not limited thereto since many modifications may be made and will become apparent to those skilled in the art. | A drill string stabilizer having either an adjacent or underlying surface affixed to the high strength drill string member which is made of easily weldable material. The easily weldable material is affixed to the drill string member by weld beads under carefully controlled temperature and other environmental conditions to ensure that such weld beads do not have cracks or blemishes created therein. The weldable material permits the welding of a wear element or blade structures to be made in uncontrolled or field conditions without adverse consequences to the resulting weld beads. Low carbon steel or weld material may be such easily weldable material, neither of which are prone to cause weld cracking, even under a field welding environment. The wear element structures may be individual elements or incorporated in a partial or complete sleeve. One embodiment includes welding a portion of the wear elements to the stabilizer body, but the areas where the high stresses occur are welded to easily weldable material, which is not nearly so susceptible to cracking. | 4 |
RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Patent Application No. 61/983,385, filed Apr. 23, 2014, the disclosure of which is incorporated herein by reference.
FIELDS OF THE INVENTION
[0002] The invention presented here relates to an ultraviolet sterilization system used for preventing the transfer of microbes, specifically in an integrated ultraviolet cash drawer. The design is used typically at a point of sale where a cash box is used to effect standard cash registration operations while seamlessly coupling ultraviolet sterilization on the cash transferred.
BACKGROUND
[0003] There are already a large number of devices described for effecting payment at a point of sale. Some have attempted to couple these devices with known anti-microbial or germicidal agents, however prior to the present invention any incorporation of these agents into cash registers or currency drawers involved commercially impractical designs and expensive manufacturing processes.
[0004] Related art includes two portable devices described in U.S. Pat. No. 4,786,812 issued on Nov. 22, 1988. This patent described for a hand-held device to sterilize a surface contaminated with mold, yeast or virus using ultraviolet (UV) lamps operating at a wavelength of 253.7 nanometers. U.S. Pat. No. 4,896,042 issued on Jan. 23, 1990 describes a two-piece device consisting of a hand-held unit with UV lamps for sterilization of surfaces and a base unit with a fan onto which the hand-held unit is secured for the sterilization of the surrounding atmosphere. Neither invention provides for or can ensure the complete decontamination of high-risk items, such as currency, during continual routine exchange of money as occurs in a check-out unit in department stores.
[0005] U.S. Pat. No. 6,753,536 describes the neutralization of chemical and biological threats using a confined drawer design that provides a contained decontamination of high-risk items such as money. The invention incorporates the use of a combination of germicidal and thermal tubes to neutralize chemical and/or biological agents. The ultraviolet lamps emit ultraviolet radiation, preferably UV-C at a wavelength of 253.7 nanometers with the heating tube generating air temperatures of at least 160° C.
[0006] In the retail industry, customers are highly susceptible to cross-contamination handling contaminated currency. Employees are constantly handling money which significantly increases their chances of infection. If employees and/or customers perceive a store and the company as begin unclean, the company brand and reputation will be affected.
[0007] None of the prior art inventions provide for or can safely and efficiently ensure complete decontamination of the currency exchanged during purchases as occurs in a check-out unit of a large retail store. Prior devices required long UV exposure times and cumbersome manipulation which delays the purchasing process normally occurring at a full service check-out station in a retail store.
[0008] A device for sterilizing currency, such as coins checks or other monetary exchange used and exchanged by the public, and that would allow an individual with little or no formal training to seamlessly and effectively decontaminate the currency while completing routine exchanged related tasks such as would occur in a check-out line of a department store or large commercial facility would provide a useful means to control the communication of germs. Thus the present invention describes a device for sanitizing cash where there would be no change or alteration of normal operations, minimal integration into the current check-out stations, and no daily recurring costs or additional employee training is needed. Further, the present invention provides a means to use germicidal ultraviolet radiation to kill contaminants found on equipment in many various industries such as health care and in food preparatory where the spread of microbes among tools and bench-top equipment has become a problem for workers and consumers in the field.
SUMMARY
[0009] Banknotes, coins, and other forms of money have always been used in circulation as a medium of exchange especially circulating paper money. Individual paper currency will be in physical contact with multiple people and consequently become an inadvertent vector for the transmission of microbes in communities. This is especially true in large retail stores where patrons select their purchase items and then proceed to a central check-out station(s) to finalize the exchange using currency. As individual currency is exchanged through a check-out clerk and subsequent purchasers, the risk of communicating a plethora of microbial organisms increases through currency contact. Individuals, especially people with suppressed immune systems, are unnecessarily exposed to multiple diseases.
[0010] The present invention incorporates an ultraviolet sterilization system for safely and efficiently irradiating money at the point of currency transactions with ultraviolet light (UVC). In one embodiment, a cash drawer incorporates, in part, an outer casing configured to substantially enclose an inner volume, an inner container configured to receive a paper currency, and a series of electrical components designed to completely irradiate with ultraviolet light, specifically UVC, the target monies in an optimized time interval that allows continued addition and removal of currency during routine purchases and exchange of money.
[0011] A further embodiment includes design modifications for easy repair and maintenance. A modular design as described herein provides for a rapid and simple manufacturing process.
[0012] The present invention provides germicidal protection for full-service check-out stations in stores, in part, by retro fitting current cash drawers with a UV system that significantly reduces or eliminates the exchange of microbes occurring with the transfer of currency. This “real time” UV irradiation and currency exchange make the present invention useful in most retail stores and large commercial entities were currency is exchanged with the public.
[0013] The embodiments of the present invention are shown in the drawings and summarized below. It is to be understood, however, that there is no intention to limit the invention to the forms described in the specification. One skilled in the art can recognize that there are numerous modifications that would embody the spirit and scope of the invention as expressed in the claims.
DESCRIPTION OF THE FIGURES
[0014] The following drawings form part of the present specification and are included to further demonstrate certain aspects of the present invention. The invention may be better understood by reference to one or more of these drawings in combination with the detailed description of specific embodiments presented herein.
[0015] FIG. 1 . Images of irradiation chamber design, Panel A single chamber area with no dividers, Panel B three chamber divider, and Panel C standard currency dividers.
[0016] FIG. 2 . Outer front face of box showing indicators LEDs, green indicates power on and blue indicates lamp on, located on the front fact of the box.
[0017] FIG. 3 . Block diagram of main control board.
[0018] FIG. 4 . Image of the micro switch design to accurately time the opening and closing of the drawer with the opening and closing of the UVC lamp. Panel A shows the V bend design. Panel B shows a modular design unit and Panel C shows the unit situated within outer box.
[0019] FIG. 5 . Image of the recessed metal pocket housing the 12 volt power connection as well as the cash drawer POS interface.
[0020] FIG. 6 . Image of the ultraviolet-C circuit board and lamp mounted to the top portion of the inner surface of the outer box.
[0021] FIG. 7 . Images of the modular design of the PCB lamp circuit board assembly. Panel A shows the UV-C circuit board and lamps mounted on an insulated platform. As shown in Panel B, a staggered pin orientation provides for simple installation.
[0022] FIG. 8 . Panel A shows an image of the protective screen inserted into position along the front and back 45 degree angle screen and platform edge. Panel B shows the modular circuit board and lamp with protective screen assembled on the inner surface of the top of the outer box. Panel C show an alternative design with standoff pins.
[0023] FIG. 9 . Image of the aluminum protective screen shown on inner surface of the top side of the currency drawer
[0024] FIG. 10 . Insider view of the aluminum protective screen showing sides angled at 90 degrees with portions cut open for wire access and on the front and back edges a 45 degree angle.
[0025] FIG. 11 . Top view of an opened drawer modified for disinfecting medical equipment.
[0026] FIG. 12 . Panels A and C are images of two petri dishes sampled from currency obtained from a restaurant and pharmacy, respectively. Each petri dish was inoculated from 3 different bills used in a typical transaction within the store and without exposing to the UV-C cash drawer system of the present invention. Panels B and D are images of petri dishes sampled from the same currency in Panel A and C, respectively, after disinfection using the UV-C in the cash drawer. Samples for each petri dish were obtained under aseptic conditions with each dish incubated for 72 hours at 32° C.
[0027] FIG. 13 . Image of the components for the kit of the present invention. The components includes natural botanical sanitizing wipes, hand sanitizer, disinfecting wipes, a disinfecting all-purpose spray cleaner and a portable microbe detection device.
DETAILED DESCRIPTION OF THE INVENTION
[0028] The device described in the present invention provides a system for significantly reducing or eliminating the exchange of microbes with the transfer of currency. One embodiment incorporates a currency box used in most commercial transactions or associated with cash registers used in large commercial entities such as retail stores. The box is equipped with a series of ultraviolet lamps (UVC) programmed to irradiate the contents such as coins and notes. The UVC bulbs and electronic circuitry provide an efficient and commercially practical means to providing a germicidal sterilizer. The box is loaded with the currency. When the drawer is closed, a calculated dose of germicidal UVC energy is delivered automatically within the box, eliminating or significantly reducing the microbes. LED displays on the outer front face of the box provide the user with the system's status, including power, lamps, and lamp use. Other embodiments of the present invention include, but not limited to, a device and a disinfecting tool used in the healthcare industry and in the food preparatory industry where cutting boards and other instruments are readily sterilized.
[0029] Kits for maintaining a germ-free checkout station are also described which compliment the device in a system that provides a complete germ-free check out station. The kit includes, in part, a botanical disinfecting wipes which further aid in the safety of the employee.
Overall UVC Germicidal and Antimicrobial System
[0030] The PCB power circuit board and lamp circuit board is designed to fit in any type of sterilization system to sterilize a multitude of products, materials or tools. The target to be irradiated is contained within a closed unit. Typical contained units are shown in FIG. 1 where a drawer within the closed box provides easy access when pulled out. As illustrated, FIG. 1 Panel A depicts a sterilization unit having an outer box frame ( 10 ) with an inner draw ( 12 ) shown without dividers. FIG. 1 Panel B is the same outer box frame ( 10 ) and inner draw ( 13 ) with compartments. While any design for dividing the inner draw is contemplated in the present invention, FIG. 1 Panel C depicts the most preferred design for the inner draw ( 14 ) having specific compartments for storing currencies of different denominations. Upon closing the inner drawer and activation of the system, the contents are exposed to a UVC source for a predetermined time period optimized to ensure complete elimination of any microbial activity on the surface of the target with the least amount of lamp usage.
[0031] One embodiment of the present invention address the need for removing microbial activity on the surface of currency as it is being exchanged in commerce, typically the full-service check-out station at a retail store. The present invention utilizes, in part, the standard design of a cash box ( 10 ) having a currency drawer (but now incorporating a UVC irradiation system ( FIG. 1 , Panel C). On the left side of the front outer face of the outer cash box are green ( 26 ) and blue ( 27 ) LED indicator lights powered directly from the circuit board described herein ( FIG. 2 ). Alternatively, a third red LED indicator light illuminates when the clock on the circuit board reaches 10,000 hours which functions to notify the user that the bulb is to be replaced. FIG. 3 provides a block diagram of the main control board, showing the interrelationships between the irradiation lamps and user indication LEDs. FIG. 3 incorporates the third red LED which alternatively can be used to assess the life of the UV bulbs.
[0032] In one embodiment inside the outer box, a secondary micro switch is incorporated with the existing micro switch of the germicidal system through a specially designed connector ( 41 ). As shown in FIG. 4 Pancel A, a V bend in the center keeps both arms of the switch connected as well as evenly separated. This insures smooth operation for the accuracy of the timing corresponding with the opening and closing of the germicidal chamber or cash drawer as well as the overall UVC operation.
[0033] In an alternate design, the LED indicator lights are positioned on the upper portion of the front face. A modular micro switch assembly is shown in FIG. 4 , Panel B. As shown in FIG. 4 , Panel C the assembly is easily mounted in the rear of the inner portion of the outer box with quick connectors.
[0034] Further the outside bottom of the outer box has a 2¾″×1½″×2″ deep metal pocket ( 55 ) modified to contain a 12 volt power connection as well as the cash drawer POS interface. By recessing this pocket and locating the connectors within the pocket, the connectors are provided protection and the drawer will sit flat. (see FIG. 5 )
[0035] Special quick release power plugs and connectors on the sterilization system as well an easily removable main PCB microprocessor circuit board and a PCB Ultraviolet-C lamp circuit board facilitate the efficient exchange of the parts of these components, allowing for cost-effective, quick and efficient service on site. The quick release plugs and connectors allow for rapid assembly and field repair.
[0036] The present invention considers all possible applications of the general embodiment of the present invention. Not only can it be applied to cash drawers, but replacement of the plastic cash drawer with a stainless steel drawer has applications in the medical and dental industry where rapid and easy sterilization of instruments or tools is needed to prevent infections.
[0037] Another application is in the food industry. One embodiment is a drawer without a bottom. The bottomless drawer is placed over cutting utensils and cutting boards in to sterilize. An optimized exposure time to the UVC irradiation allows complete sterilization in-situ. Typical application would involve sterilization of a wood cutting board by simply placing the bottomless drawer over the target cutting board and exposing to UVC irradiation for a predetermined time period.
UVC—PCB Circuit Board Germicidial Sterilizer
[0038] FIG. 3 shows a block diagram of the main control board. All components are UL certified or are UL recognized components. A 2 pin male connector links the 12 volt DC input with a 3 amp fuse on circuit board. Another 2-Pin male connects to 2 pin female connector attached to 18 gauge+−wires that connect to a 2.1 mm barrel power connector that installs in the bottom of the unit in the recessed pocket. The unit further contains (4) AC/DC high voltage rms transformers.
[0039] A microcomputer processor mounted on shock absorbing rubber grommets is incorporated to provide a custom program and a micro switch which functions in the assimilation of a one shot timer, controlling the transformers and LEDs. The blue LED UVC indicator light and the UVC germicidal lamps are switched on or off to indicate the status of the power or UV light, respectively. The processor also controls a potentiometer to supply the time required for the antimicrobial process. It is used to monitor, store and display the information and is set by two separate minute and second push button digital micro switches which when pressed will display the time that the UVC lamps will remain active, resulting in a much improved accuracy in regulating the amount of time the UV light is on, allowing for improved optimization of irradiation time intervals, and in standardizing the manufacture/product of multiple devices for a specific application. The processor is also used to monitor, store and display the information of the total accumulated time the UVC lamps have been active, thus providing an indication for replacement. The processor is responsible for monitoring and sending information to the red LED light when the life of the lamps has been exhausted and notifying the user to replace lamps. The LED green light on the front outside face of sterilization unit is constantly illuminated when power is applied to the unit. LED blue light on front outside face of the sterilization unit is illuminated only when power is applied from the micro switch, causing the microcomputer processor to engage the AC inverter to power the UVC bulbs and engage the timer, potentiometer and the LCD or LED readout. The LED (or LCD) panel on the outer front face of circuit board is controlled by the microcomputer processor which sends commands to the LED or LCD panel to display the accumulated time the UVC bulbs have been on. On the main PCB circuit board there are 2 brown male 11 pin output connectors. These connectors receive a set of custom designed 5000 k AC voltage silicone wires consisting of 4 red power and one white ground for AC voltage. Each set of cables has a brown female 11 pin connector on one end that connect to the circuit board and a white female 11 pin connector that connects to the Ultraviolet-C lamp circuit board.
The PCB Ultraviolet-C Lamp Circuit Board
[0040] The PCB Ultraviolet-C (UVC) lamp and circuit board is shown in FIG. 6 . FIG. 6 shows one embodiment where the board is 14 inch by 2⅞ inch with one white 11 pin male connector input ( 61 ). The 11 pin male connector is soldered to four traces that are designed for two germicidal UVC lamps, 5 watt, (5 mm×240 mm) having 253.7 nm wavelength with 2600 microwatts at 1 inch per cm 2 . The lamps are staggered 2″ left to right on the Ultraviolet-C lamp circuit board to provide complete coverage of the target area. These lamps are also soldered onto the Ultraviolet-C lamp circuit board so as to maintain a secure connection throughout their use. The lamps are designed to start quickly by using 1500 vrms to start and 900 vrms to run. This combination of power, size and characteristics of the lamp provides a unique feature to the lamps in the present invention, allowing them to start and reach its full power potential while killing 99.999% of germs within seconds instead of the minutes needed in the prior art. Thus the lamp allows faster service treatment on/off times when used and ensures complete irradiation during routine on/off use.
[0041] The PCB lamp circuit board has 3 holes uniformly on each side of board ( 63 ). These holes allow a threaded brass insert attached to a steel pin which accompanies a rubber grommet to allow for shock absorption and for the circuit board to float above the attachment surface. A further embodiment of the PCB Lamp circuit board is a ⅜″×12″ strip of hook and loop Velcro on back of the length of board making board simple to exchange when lamps need to be replaced.
[0042] A further embodiment of the PCB Ultraviolet-C (UVC) lamp and circuit board is shown in FIG. 7 . FIG. 7 Panel A shows a modular UVC lamp unit for assembly into a UV cash box. Two separate PCB lamp circuit board assemblies ( 65 ), each having two UV-C lamps are mounted on the circuit board. The PCB lamp circuit board assemblies ( 65 ) are easily mounted on an aluminum platform ( 67 ) having an insulated surface and using a staggered pin orientation ( 66 ) as shown in Panel B. An aluminum perforated protective screen ( 68 ) as described below covers the Ultraviolet-C (UVC) lamp and circuit board. The protective screen is inserted onto the aluminum plate ( 67 ) along the front and back 45 degree angle screen edge and a corresponding 45 degree angle edge of the aluminum platform as shown in FIG. 8 Panel A. Once assembled the modular lamp component is quickly and easily installed with 4 screws ( 71 ) onto a support platform ( 72 ) on the inner top surface of the outer box. The circuit board and lamp are connected to the unit through a two circuit board connectors ( 73 ) having a hold-down shield ( 74 ) as shown in FIG. 8 Panel B. Panel C depicts another embodiment which incorporates the modular design with standoff pins ( 75 ) in the center of the aluminum platform ( 67 ) to support the screen and allow for it to be screwed down.
The Aluminum Perforated Protective Screen
[0043] As shown in FIG. 9 , a 15″×8″ an aluminum perforated protective screen protects the boards from damage and allows the target, such as coins or paper notes, to be exposed to the generated radiation. FIG. 9 shows the outer box with the bottom side up and with the drawer removed. The aluminum perforated screen ( 68 ) is attached to the inner surface of the top side of the outer box ( 10 ). As shown in FIG. 10 , the screen is angled at 90 degrees on each side with portions cut open for wire access ( 81 ) and on the front and back edges up, at a 45 degree angle so as to raise the center of the screen to provide a protective area for the PCB Lamp circuit board. The 45 degree angle also provides deflection for the drawer if it happens to be raised or the system is abused. The system is capable of preventing a high degree of abuse and will not allow the bulbs to break. If the bulbs do break, the screen will provide containment and will not allow the broken lamp to fall into the drawer. The perforation on the screen allows the 254.7 nm light waves to penetrate through and be effective in sterilizing the contents of the drawer. In addition, the screen is painted black on the back side as to not allow any reflection of the light wave so the full strength of the light wave moves through the perforated protective screen.
[0044] As discussed above, the present invention has applications in the healthcare industry (see FIG. 11 ). One embodiment is the use of the outside box ( 10 ) and drawer ( 12 ) in disinfecting medical instruments prior to use. Specially designed compartments enable complete exposure of the surface of each tool to the UV-C radiation, thereby ensuring uniform disinfection. To this end, stainless steel compartments allow light to be reflected from all interior drawer surfaces. A mesh platform ( 95 ) sits slightly above the bottom surface of the compartment. The mesh pattern is sufficiently porous as to allow UV-C light to reflect of the bottom drawer surface to irradiate the underside of the tool. FIG. 11 shows a typical medical sterilization drawer having three compartments for positioning medical and surgical tools for UV-C irradiation. Each compartment is fitted for a mesh platform as shown.
[0045] A further embodiment contemplated in the present invention is the incorporation of a small credit card size computer with WIFI capabilities. Together with a cell phone application to collect data on the status of the cash drawer (or other device of the present invention), individual cash drawers are monitored in real-time: For example, the application can assess the status of the power supply or information from the indicator lights. Information regarding the UV lamps relating to on/off time or time each lamp is on, record of the lifetime on the UVC bulbs to indicate replacement, the temperature inside the cash drawer, the number of times the cash drawer opens in a unit of time, detecting the cash drawer open time and assess. Thus if left open to long (theft or another problem), appropriate action can be quickly initiated. These all are set to be monitored without supervision and send a communication by e-mail to the responsible party as well as the owner, informing them that there is any type of problems with the drawer.
Sample Test
[0046] In order to further confirm the ability of the cash drawer to completely affect microbes and disinfect the surface of any currency transferred during the completion of a purchase or at the check-out station, three separate bills were randomly tested from two actively currency transacting stores, a restaurant and a pharmacy. Each selected bill was aseptically stored and transferred by sterile techniques prior to testing. Testing was completed by independently swabbing the surface of the collected bills before and after exposure to the UV-C cash drawer system described in the present invention. Petri dishes were incubated for 72 hours at 32° C. and then assessed for microbial growth on the agar.
[0047] In the first experiment ( FIG. 12 , Panel A and B), currency exchanged from a fast-food restaurant was selected. Three bills were each independently swabbed to inoculate a sterile petri dish in three separate regions as shown. Panel A depicts growth in each region after 72 hours of incubation. While each bill had varying amounts of microbial growth, Panel A shows the presence of microbes growing on the petri dish in each region, representing their presence on the surface of the sampled bills. In Panel B, the same currency has now been disinfected using the UV-C cash drawer disinfection system of the present invention. Here, microbe growth has been significantly attenuated, if not completely inhibited, after exposure of the bills to the UV-C cash drawer system.
[0048] In the second experiment ( FIG. 12 , Panel C and D), currency exchanged from a pharmacy was selected. Again, three bills were each independently swabbed to inoculate a sterile petri dish in three separate regions. Panel C shows a significantly greater amount of infection in all three bills compared to the restaurant sample, but especially noteworthy is Panel D where the growth is again completely inhibited on all three samples after exposure to the UV-C cash drawer system.
Kit and System for a Complete Anti-Germicidal Protection System
[0049] In addition to the device described above, a complete system is disclosed herein for continued, long-term protection against microbes and other biological agents found and transmitted at most large commercial full-size check-out stations, such as those found at a department store or discount retail stores. The kit ensures all surfaces and employee/user hands are cleaned and monitored for a clean store environment. The kit includes, in part, natural botanical sanitizing wipes, hand sanitizer, disinfecting wipes, and a disinfecting all-purpose spray cleaner (see FIG. 13 ).
[0050] Most disinfectant wipes incorporate alcohols, aldehydes, oxidizing agents, phenolics, and quaternary ammonium compounds. Each has known properties and toxicities with varying safety standards. For example, bleach is commonly used to sanitize, especially in areas used by children. Bleach is a chemical irritant to the lungs and mucous membranes and is especially toxic to the individual who is diluting or cleaning the surface.
[0051] However the present invention considers a natural botanical alternative incorporated into the kit components, providing the safest work environment available for employees working at the store's full-service check-out station and customers. Natural botanical ingredients used in the formulation of the present invention include thymus vulgaris oil (thyme oil with is a natural antimicrobial), citric acid (an antioxidant and environmentally benign cleaning agent), sodium decylglucosides hydroxypropyl sulfonate (a plant-based emulsifier derived from corn sugar and coconut oil), hydrolyzed oats (a skin conditioner), origanum vulgare (oregano) oil (a natural essential oil fragrance), aloe barbadensis leaf (aloe vera, a natural emollient and skin conditioner), copper PCA (a skin conditioner and naturally occurring mineral found in human skin), sodium citrate (a natural pH balancer), and water.
[0052] The only known natural disinfectants are botanical disinfectants. Botanical disinfectants are known to kill over 99.99% of bacteria, fungus and other microbes. They are applied without mixing, requiring no rinsing or wiping to remove. It can be used to sanitize such areas as a child care facility. It is most applicable in a work environment where an effective disinfectant is needed, yet the application must be safe for employees and other personnel who come in contact.
[0053] As a verification component of the kit, a portable microbe detection device is included with the kit in order to sample the individual check-out stations and monitor for the presence of microbes. While all detection devices known in the art are considered, the preferred device utilizes the detection of ATP. This is the simplest and most cost-effective rapid testing means for measuring mold, bacteria and other microbes.
[0054] The kit further contains information and instructions to optimize the use of the botanical disinfectant and a testing schedule for sampling with the portable microbe detection device.
[0055] The contents of the articles, patents, and patents applications and all other documents and electronically available information mentioned or cited herein, are hereby incorporated by reference in their entirety to the same extent as if each individual publication was specifically and individually indicated to be incorporated by reference.
[0056] The terms and expressions used herein have been used as terms of description and not of limitation, and there is no intention in the use of such terms of excluding any equivalents of the features shown and described or portions thereof. It is recognized that various modification are possible within the scope of the invention claimed. Thus, it should be understood that although the present invention has been specifically disclosed by preferred embodiments and other features, modification and variation of the invention embodied therein herein disclosed may be used by those skilled in the art, and that such modification and variations are considered to be within the scope of this invention. | The invention relates to a system, methods and apparatus for efficiently and cost-effectively preventing the transfer of microbes, such as, for example, bacteria and viruses seamlessly during commercial transactions typically occurring at a full service check-out station in a large retail store. The invention further considers the application of the methods and apparatus in other industrial disciplines where, for example, medical equipment and surgical tools may be susceptible to cross-contamination of microbes. One preferred embodiment incorporates a slidable drawer within a cash box where currency is stored, taken, or added randomly over a period of time. Especially designed lamps allow for a rapid switching means to control the time period for activating or deactivating lamps, thus regulating UV exposure. Exposure time with UVC and the orientation of the UV lamps provides complete germicidal decontamination within seconds. | 0 |
FIELD OF THE INVENTION
[0001] The present invention generally relates to a fuel bladder apparatus and method. More particularly, the present invention pertains to a low permeability fuel bladder to store and provide fuel for an engine and method for storing and providing fuel for an engine.
BACKGROUND OF THE INVENTION
[0002] Fuel burning engines are utilized to provide power in a vast array of applications. Generally, a fuel tank is utilized to store and provide a ready supply of fuel for the engine. Typically, the fuel tank is a container with relatively rigid sides of metal or plastic and a cap that is removed to fill the fuel tank. The cap is vented to allow air into the tank. In use, as fuel is drawn out of the tank to be combusted in the engine, the volume of fuel removed is displaced by fuel vapor and air drawn in through the vent in the cap. Without this venting, a partial vacuum may form in the tank and fuel may cease to flow to the engine. Unfortunately, the vented cap also allows fuel vapor to escape into the environment.
[0003] To reduce this escape of fuel, some conventional tank systems employ a carbon filter in line with a tank vent to absorb fuel vapors. For example, carbon filters have been utilized in the automotive industry with some success. Compared to the cost of a automobile, the added cost of a carbon filter or vapor recovery system is relative low. However, compared to the cost of most yard equipment, the added cost of a carbon filter may be relatively expensive. In addition, although a carbon filter reduces pollution that results from fuel vapors escaping from the tank out into the environment via permeation or effusion through the wall of the fuel tank, to re-fill the tank, the cap is opened and, as fuel is poured into the fuel tank, the fuel vapor in the tank is displaced by the added volume of fuel and expelled from the inlet.
[0004] Accordingly, it is desirable to provide a method and apparatus capable of overcoming the disadvantages described herein at least to some extent.
SUMMARY OF THE INVENTION
[0005] The foregoing needs are met, to a great extent, by the present invention, wherein in one respect a fuel bladder to store and provide fuel for an engine and method for storing and providing fuel for an engine is provided.
[0006] An embodiment of the present invention pertains to a fuel bladder apparatus. The fuel bladder apparatus includes a fuel bladder, tank, and cap. The fuel bladder includes an elastomeric envelope, fuel inlet, and fuel outlet. The elastomeric envelope has an upper section, lower section and side section. The fuel inlet is disposed at the upper section. The fuel outlet is disposed at the lower section. The tank includes a rigid housing, inlet port, outlet port, and air inlet. The inlet port is disposed in cooperative alignment with the fuel inlet. The fuel inlet is sealed to the inlet port. The outlet port is disposed in cooperative alignment with the fuel outlet. The cap is detachably secured to the inlet port. The cap detachably seals the fuel inlet.
[0007] Another embodiment of the present invention relates to an apparatus for supplying fuel to a yard equipment engine. The apparatus includes a means for disposing a fuel bladder in a tank and means for sealing the fuel inlet to the inlet port to generate a fuel bladder volume and a tank volume. The means for disposing a fuel bladder in a tank includes an elastomeric envelope, fuel inlet, and fuel outlet. The elastomeric envelope has an upper section, lower section and side section. The fuel inlet is disposed at the upper section. The fuel outlet is disposed at the lower section. The tank includes a rigid housing, an inlet port, outlet port, and air port. The inlet port is disposed in cooperative alignment with the fuel inlet. The outlet port is disposed in cooperative alignment with the fuel outlet. The fuel bladder volume is fluidly isolated from the tank volume. The tank volume is in fluid connection with the atmosphere via the air port. Air from the atmosphere enters the tank volume via the air port in response to fuel being removed from the fuel bladder and air.
[0008] Yet another embodiment of the present invention pertains to a method of supplying fuel to a yard equipment engine. In this method a fuel bladder is disposed in a tank. The fuel bladder includes an elastomeric envelope, fuel inlet, and fuel outlet. The elastomeric envelope has an upper section, lower section and side section. The fuel inlet is disposed at the upper section. The fuel outlet is disposed at the lower section. The tank includes a rigid housing, inlet port, outlet port and air port. The inlet port is disposed in cooperative alignment with the fuel inlet. The outlet port is disposed in cooperative alignment with the fuel outlet. The fuel inlet is sealed to the inlet port to generate a fuel bladder volume and a tank volume. The fuel bladder volume is fluidly isolated from the tank volume. The tank volume is in fluid connection with the atmosphere via the air port. Air from the atmosphere enters the tank volume via the air port in response to fuel being removed from the fuel bladder and air.
[0009] There has thus been outlined, rather broadly, certain embodiments of the invention in order that the detailed description thereof herein may be better understood, and in order that the present contribution to the art may be better appreciated. There are, of course, additional embodiments of the invention that will be described below and which will form the subject matter of the claims appended hereto.
[0010] 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 embodiments in addition to those described and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein, as well as the abstract, are for the purpose of description and should not be regarded as limiting.
[0011] 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.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a partial cut-away side view of a fuel tank and fuel bladder according to an embodiment of the invention and an engine suitable for use with the fuel tank.
[0013] FIG. 2 is a cut-away view of the fuel tank and fuel bladder of FIG. 1 in a filled condition.
[0014] FIG. 3 is a cut-away view of the fuel tank and fuel bladder of FIG. 1 in a partially filled condition.
[0015] FIG. 4 is a cut-away view of the fuel tank and fuel bladder of FIG. 1 in an empty condition.
[0016] FIG. 5 is a cut-away view of a fuel tank and fuel bladder according to another embodiment.
[0017] FIG. 6 is a partial cut-away view of the fuel tank and fuel bladder according to FIG. 5 in a partially filled condition.
[0018] FIG. 7 is a cut-away view of a fuel tank and fuel bladder according to another embodiment.
[0019] FIG. 8 is a partial cut-away view of the fuel tank and fuel bladder according to FIG. 7 in a partially filled condition.
DETAILED DESCRIPTION
[0020] Preferred embodiments of the invention will now be described with reference to the drawing figures, in which like reference numerals refer to like parts throughout. As shown in FIG. 1 , a power unit 10 includes an engine 12 and a fuel apparatus 14 . In a preferred embodiment, the engine 12 is an internal combustion engine that utilizes any suitable fuel such as gas, diesel, and/or other such liquid fuel. In a particular example, the engine 12 is suitable for use to power yard equipment such as a lawn mower, tiller, chipper, snow blower, power washer, or the like. The fuel apparatus 14 is configured to store and/or supply the fuel to the engine 12 . In one example of a preferred embodiment, the fuel apparatus 14 includes a fuel bladder 16 and tank 18 .
[0021] In general, the fuel bladder 16 includes an envelope or container that is compatible with fuel and is impermeable or has a low fuel permeability. In various embodiments, the fuel bladder 16 may include any suitable flexible or elastomeric material. Examples of suitable elastomeric materials includes rubber, poly tetra fluoro ethylene (“PTFE”), poly ether ether ketone (“PEEK”), thermoplastic urethane, and the like. The elastomeric material may be utilized alone or as a coating. In a particular example, the fuel bladder 16 may include a rubber or polymer coated fabric. Rubber or polymer coated fabric may provide improved abrasion resistance as compared to fuel bladders without fabric reinforcement. The fuel bladder 16 includes a fuel inlet 20 and fuel outlet 22 . The fuel inlet 20 is configured to receive fuel that is poured or otherwise introduced to the fuel bladder 16 . When not actively being filled, the fuel inlet 20 may be sealed via a cap 24 . The fuel outlet 22 is disposed to draw fuel out of the fuel bladder 16 . In a particular example, the fuel outlet 22 is disposed at a low portion or bottom of the fuel bladder 16 .
[0022] The tank 18 may be a relatively rigid housing or container to protect the fuel bladder 16 , contain leaked fuel in the event of damage to the fuel bladder 16 , and/or secure the fuel apparatus 14 to the engine 12 . To this end, the tank 18 may be fabricated from any suitable material such as, for example, metal, plastic, or the like. The tank 18 includes an inlet port 26 , outlet port 28 , and air port 30 . The inlet port 26 is secured or affixed to the fuel inlet 20 . For example, the inlet port 26 may be secured to the fuel inlet 20 by an adhesive and/or mechanical fastener. The outlet port 28 provides access to the fuel outlet 22 and/or an opening through which a fuel line 32 may fluidly connect the fuel bladder 16 to the engine 12 . The air port 30 is configured to facilitate an ingress and egress of air into and out of the tank 18 . That is, the air port allows and essentially free exchange of air into and out of the tank 18 . It is an advantage of various embodiments of the invention that fuel and fuel vapors are essentially prevented from escaping into the environment during this free exchange of air. That is, due to the fuel bladder 16 , the tank 18 is divided into two distinct volumes, for example, a free tank volume 34 and a bladder volume 36 . As fuel from the fuel bladder 16 is utilized by the engine 12 , the bladder volume 36 is reduced. Air enters the free tank volume 34 via the air port 30 to offset the reduction in the bladder volume 36 . Conversely, in response to an increase in the bladder volume 36 , air may exit the air port 30 . For example, in response to introducing fuel to the fuel bladder 16 via the fuel inlet 20 , the bladder volume 36 may increase and the free tank volume 34 may decrease as air exits via the air port 30 . In this manner, the air port 30 facilitates an ambient pressure equilibrium in the tank 18 acting upon the fuel bladder 16 .
[0023] FIG. 2 is a cut-away view of the tank 18 and fuel bladder 16 of FIG. 1 in a filled condition. As shown in FIG. 2 , the fuel bladder 16 essentially fills the tank 18 and the free tank volume 34 is relatively small. Also shown in FIG. 2 , the air port 30 may include a cover or other such structure to reduce the inflow of contaminants such as, for example, dirt, water, insects, etc. In other examples, the air port 30 may include a filter such as, fabric, fibers, or the like, to reduce the inflow of contaminants into the free tank volume 34 .
[0024] FIG. 3 is a cut-away view of the tank 18 and fuel bladder 16 of FIG. 1 in a partially filled condition. As shown in FIG. 3 , the partially filled fuel bladder 16 occupies relatively less of the tank 18 than the filled fuel bladder 16 shown in FIG. 2 . In addition, the free tank volume 34 is relatively greater than shown in FIG. 2 . According to another embodiment, the air port 30 may be disposed near or integrated into the inlet port 26 . It is an advantage of this embodiment that the cap 24 may partially cover the air port 30 and thereby reduce inflow of contaminants into the free tank volume 34 .
[0025] FIG. 4 is a cut-away view of the tank 18 and fuel bladder 16 of FIG. 1 in an empty condition. As shown in FIG. 4 , the essentially empty fuel bladder 16 occupies relatively less of the tank 18 than the filled or partially filled fuel bladder 16 shown in FIGS. 2 and 3 . In addition, the free tank volume 34 is relatively greater than shown in FIGS. 2 and 3 . According to another embodiment, the air port 30 may be disposed near or integrated into the inlet port 26 . It is an advantage of this embodiment that the cap 24 may partially cover the air port 30 and thereby reduce inflow of contaminants into the free tank volume 34 .
[0026] FIG. 5 is a cut-away view of a tank 18 and fuel bladder 16 according to another embodiment. As shown in FIG. 5 , the inlet port 26 includes an inlet tube 38 that extends into the tank 18 . According to this embodiment, the fuel bladder 16 expands and contracts by sliding along this inlet tube. The fuel bladder 16 includes a series of pleats 40 , a float 42 , and a seal 44 .
[0027] The pleats 40 facilitate expansion and contraction of the fuel bladder 16 . For example, in a manner similar to the pleats in a bellows, the pleats 40 facilitate an orderly and efficient contraction and expansion of the fuel bladder 16 .
[0028] The float 42 provides buoyancy to the top of the fuel bladder 16 in order to keep the top of the fuel bladder 16 floating above any fuel present in the fuel bladder 16 . In this regard, the density of the float 42 is relatively less than that of fuel. For example, the float 42 may include air, foam, or the like.
[0029] The seal 44 is disposed at an interface between the inlet tube 38 and the float 42 . The seal 44 translates along the inlet tube 38 . The seal 44 may provide a substantially fuel impermeable or fuel resistant interface to reduce leakage of fuel from the fuel bladder 16 into the free tank volume 34 and/or out of the tank 18 .
[0030] The fuel bladder 16 shown in FIG. 5 is essentially full of fuel, for example. Accordingly, the free tank volume 34 is relatively small. As shown in FIG. 6 , the fuel bladder 16 is substantially empty. As such, the pleats 40 are shown in a relatively compressed state, the bladder volume 36 is relatively low, and the free tank volume 34 is relatively high.
[0031] FIG. 7 is a cut-away view of a tank 18 and fuel bladder 16 according to another embodiment. As shown in FIG. 7 , the fuel apparatus 14 may be curved, rounded, or the like. In a particular example, the tank 18 may include a clamshell or clamshell-like shape and the fuel bladder 16 may be configured to substantially fill the tank 18 when full. It is an advantage of this embodiment that the fuel bladder 16 collapses or “pancakes” down upon itself readily. As such, the fuel bladder 16 may modulate according to the bladder volume 36 without the need for pleats.
[0032] In addition, the fuel apparatus 14 optionally includes a gasket 46 to seal the fuel inlet 20 and/or the inlet port 26 . If present, the gasket 46 may include an elastomeric material disposed between the cap 24 and the fuel inlet 20 and/or the inlet port 26 , for example. In a particular example, the gasket 46 maybe affixed to the underside of the cap 24 and configured to engage the inlet port 26 in response to securing the cap 24 to the inlet port 26 .
[0033] FIG. 8 is a partial cut-away view of the tank 18 and fuel bladder 16 according to FIG. 7 in an essentially empty condition. As shown in FIG. 8 , the fuel bladder 16 essentially collapses upon itself in an efficient manner. As such, substantially all or most of the fuel from the fuel bladder 16 may be utilized by the engine 12 shown in FIG. 1 . In addition, the fuel bladder 16 readily expands in response to the addition of fuel e.g., by pouring fuel into the fuel inlet 20 .
[0034] The many features and advantages of the invention are apparent from the detailed specification, and thus, it is intended by the appended claims to cover all such features and advantages of the invention which fall within the true spirit and scope of the invention. Further, since numerous modifications and variations will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation illustrated and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention. | A fuel bladder apparatus includes a fuel bladder, tank, and cap. The fuel bladder includes an elastomeric envelope, fuel inlet, and fuel outlet. The elastomeric envelope has an upper section, lower section and side section. The fuel inlet is disposed at the upper section. The fuel outlet is disposed at the lower section. The tank includes a rigid housing, inlet port, outlet port, and air inlet. The inlet port is disposed in cooperative alignment with the fuel inlet. The fuel inlet is sealed to the inlet port. The outlet port is disposed in cooperative alignment with the fuel outlet. The cap is detachably secured to the inlet port. The cap detachably seals the fuel inlet. | 5 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to processes and assemblies for identifying and tracking assets, such as tubulars, equipment and tools used in subterranean wells, and more particularly, to processes and assemblies for identifying and tracking such assets which facilitates accurate input of data into a data base.
[0003] 2. Description of Related Art
[0004] Tubulars are commonly employed in subterranean wells. During drilling of a subterranean well bore, a drill bit is secured to one end of a drill string which is made up of individual lengths of drill pipe. These lengths are conventionally secured together by means of a threaded collar. After the drill bit is secured to a first length of drill pipe, the bit and first length of drill pipe are lowered to the ground and usually rotated to permit the bit to penetrate the earth. Drilling fluid is circulated via the interior of the pipe to the drill bit to lubricate the bit and to carry cuttings back to the drilling rig at the surface of the earth via the annulus formed between the bore hole being drilled and the drill pipe. As drilling progresses, additional lengths of drill pipe are secured to the uppermost length of drill pipe in the well bore. As this process continues, a drill string is formed that is made up of individual lengths of drill pipe secured together. Once the well bore is drilled to the desired depth, the well bore is completed by positioning a casing string within the well bore to increase the integrity thereof and provide a path for producing fluids to the surface. The casing string is normally made up of individual lengths of relatively large diameter metal tubulars which are secured together by any suitable means, for example screw threads or welds. Usually, each length of casing is provided with male screw threads at each end thereof and individual lengths of casing are joined together by means of a collar having female screw threads at each end thereof. Conventionally, after the casing string is cemented to the well bore face and perforated to establish fluid communication between the subterranean formation and the interior of the casing string, a production tubing string is positioned within the casing string to convey fluids produced into the well to the surface of the earth. Tubing strings are conventionally made up of individual lengths of relatively small diameter tubing secured together by collars in a manner as described above with respect to casing. Tubing strings may also be used to convey fluids to treat the well or a subterranean formation of interest or to convey tools or equipment, such as packers, plugs, etc., that are needed to complete or work over a well Tubulars are transported to the well site in anticipation of an operation and are temporarily stored there until deployed into a well. At the well site, each length of tubular is measured or “tagged” to determine the exact length thereof. Because each tubular as manufactured usually varies in length, it is important to determine and know the exact length thereof so that the total length of a given tubular string that is positioned in a subterranean well is known. As the first tubular of a given string is positioned in a well, the tubular is designated with a first number, e.g. 1, and the length thereof is manually recorded at the well site into either a paper or computer data base. As each subsequent individual length of tubular is secured to the tubular string already positioned in the well, the next consecutive number that is assigned to that tubular and its exact length is also manually recorded into the data base at the well site. In this manner, the exact number of tubulars that make up a given string positioned in a subterranean well and the exact length of the string is known. The compilation of a data base in this manner is also desirable so as to maintain an accurate history of the usage of tubulars, equipment and/or tools. Such history of usage can be used to provide maintenance and predict potential problems. However, problems routinely occur with this procedure due to manual error(s) in entering into the data base tubular length(s) that are not part of the tubular string positioned in a well, in entering the wrong sequence of individual tubular lengths that make up a string, and/or in failing to enter an individual tubular length(s) that is part of a tubular string positioned in a subterranean well. Such errors lead to time consuming problem solving, while expensive rigs are often present at the well site, to determine the precise depth of the well, of a certain individual length of casing, and/or of a certain downhole tool. Further problems occur with this conventional method when tubulars are withdrawn from the well bore, temporarily stored on site and subsequently used in a different operation at that well or transported and used in a different well. In accordance with this conventional method, individual lengths of tubulars removed from a well are stacked at the well site without any consideration given to the number assigned to that tubular as run into the well. The individual length of tubulars are not actually physically marked with a designation number and marking such tubulars as they are being pulled from a well is not practical since the rig necessary for performing this operation is expensive. In some instances, individual lengths of drill pipe are provided with a unique serial number from the manufacturer which is entered into the data base as the drill string is being made up. However, such entry is expensive and plagued by manual errors, and often, the serial number of an individual length of drill pipe is not easily found or illegible if found due to rust, corrosion, wear, etc.
[0005] In an effort to automate the data input process and to provide a completely accurate information data base, a system has been developed to track asset inventory wherein an electronic tag, such as a passive radio frequency chip, is attached to articles of manufacture that are used in the oil & gas industry. A hand held wand is employed by field personnel to read such electronic tag and the code gleaned during such reading is transferred by cable to a hand held portable terminal. This information is then sent to a personal computer. This system is commercially available from Den-Con Tool Company. of Oklahoma City, Okla. under the trade name designation “Print System”. However, electronic tags, such as a passive radio frequency chip, do not transmit through steel, and therefor, require field personnel to position the hand held wand adjacent and close to the tag to read it. Thus, the use of this system at field locations, such as drilling and completion rigs, offshore platforms etc., has proved to be inefficient since field personnel must first locate the position of the electronic tag and then properly position the wand in extremely close proximity to the tag, sometimes repeating the procedure to ensure that the tag is properly read. This is time consuming and expensive.
[0006] Thus, a need exists for an identification and tracking method wherein individual lengths of tubulars, pieces of equipment or tools are accurately identified and inventoried prior to deployment in a given subterranean well, as positioned in a well and/or as stacked at a well site after being pulled from a well and awaiting deployment in the same or different wells. A further need exists for effectively eliminating errors in data base entry for information about individual lengths of tubulars, equipment and/or tools. A still further need exists for eliminating time delays associated with automated reading of radio frequency identification devices employed to identify and track tubulars or other tools or equipment.
SUMMARY OF THE INVENTION
[0007] To achieve the foregoing and other objects, and in accordance with the purposes of the present invention, as embodied and broadly described herein, one characterization of the present invention may comprise an assembly is provided for identifying and tracking an asset. The assembly comprises a responding device adapted to be connected to an asset and an antenna electrically connected to said responding device.
[0008] In another characterization of the present invention, an assembly is provided for use as a fluid conduit. The assembly comprises a tubular, a responding device connected to the tubular, and an antenna electrically connected to the responding device.
[0009] In yet another characterization of the present invention, an assembly is provided for use as a fluid conduit. The assembly comprises a tubular, a collar releasably secured to one end of the tubular, the collar comprising a generally tubular body, a responding device connected to the generally tubular body, and an antenna electrically connected to the responding device.
[0010] In still another characterization of the present invention, a process for identifying and tracking assets is provided which comprises positioning a transceiver in proximity to an asset having a responding device and an antenna electrically connected to the responding device so as to permit communication between the transceiver and the responding device via the antenna.
[0011] In yet still another characterization of the present invention, a process for identifying and tracking tubulars is provided which comprises positioning a transceiver and a tubular having a responding device and an antenna electrically connected to the responding device in proximity to each other without regard to the rotational orientation of the tubular so as to permit communication between the transceiver and the responding device via the antenna.
[0012] In yet still another characterization of the present invention, a process is provided for identifying and tracking assets which comprises positioning an asset having a responding device connected thereto within a transceiver having a generally annular antenna so as to permit communication between the transceiver and the responding device via said antenna.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The accompanying drawings, which are incorporated in and form a part of the specification, illustrate the embodiments of the present invention and, together with the description, serve to explain the principles of the invention.
[0014] In the drawings:
[0015] [0015]FIG. 1 is a partially cutaway, perspective view of one embodiment of the process and assembly of the present invention;
[0016] [0016]FIG. 1A is a blown up portion, as outlined in FIG. 1, of the embodiment of the process and assembly of the present invention that is illustrated in FIG. 1;
[0017] [0017]FIG. 2 is a partially cutaway, perspective view of another embodiment of the process of the present invention;
[0018] [0018]FIG. 2A is a blown up portion, as outlined in FIG. 2, of the embodiment of the process and assembly of the present invention that is illustrated in FIG. 2:
[0019] [0019]FIG. 3 is a partially cutaway, perspective view of still another embodiment of the present invention;
[0020] [0020]FIG. 3A is a blown up portion, as outlined in FIG. 3, of the embodiment of the process and assembly of the present invention that is illustrated in FIG. 3; and
[0021] [0021]FIG. 4 is a partially sectioned, perspective view of a responding device being read by a transceiver in accordance with the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0022] As utilized throughout this specification, the term “asset” refers to any article of manufacture or device, which includes, but is not limited to, tubulars, equipment and tools designed to be run on, connected to and/or operated by tubulars. As utilized throughout this specification, the term “tubular” refers to an individual length of any generally tubular conduit for transporting fluid, particularly oil, gas and/or water in and/or from a subterranean well and/or transportation terminal. When referring to a “tubular” which is used in a subterranean well, tubulars are usually secured together by means of collars to form a string of tubulars, such as a tubing string, drill string, casing string, etc., which is positioned in a subterranean well as utilized, at least in part, to transport fluids. Environments other than a subterranean well in which tubulars may be used in accordance with the present invention, include, but are not limited to, pipelines and sewer lines.
[0023] Referring to FIG. 1, a portion of two tubulars are illustrated as 2 and 6 . Each end of tubulars 2 and 6 may be provided with screw threads. As illustrated in FIG. 1, the outer surface of one end 3 and 7 of tubulars 2 and 6 , respectively, are provided with screw threads 4 and 8 . A collar 10 is utilized to secure ends 3 and 7 of tubulars 2 and 6 together. The internal surface of collar 10 is provided with screw threads 12 which threads 4 and 8 are mated with.
[0024] In accordance with the embodiment of the present invention as illustrated in FIG. 1, the outer surface of collar 10 is provided with a groove or trough 14 which extends about substantially the entire circumference or periphery of collar 10 . A responding device 20 , for example a radio frequency identification device (known as a “RFID”), is positioned in groove 14 . This radio frequency identification device 20 may be in the form of a passive radio identification device (know as a “PRID”). Such PRIDs are conventional and are used for merchandise security in the retail industry, library security, etc., and generally comprise a solid state printed circuit which is configured to resonate upon receipt of radio frequency energy from a radio transmission of appropriate frequency and strength. Such devices do not require any additional power source, as the energy received from the transmission provides sufficient power for the device to respond with a weak and/or periodic reply transmission so long as it is receiving an appropriate transmission.
[0025] Alternatively, the responding device 20 may be in the form of an active device, requiring a separate source of electrical power (e.g., electrical storage battery or other electrical power means). Such devices are also conventional, and may be configured to draw practically no electrical power until a radio frequency signal is received, whereupon they are electrically energized to produce a responding transmission.
[0026] In accordance with one embodiment of the present invention, an antenna 24 is electrically connected to the responding device 20 by any suitable means, such as by silver solder or welds, and is positioned within groove 14 and extends about substantially the entire circumference or periphery of collar 10 . Antenna 24 may be constructed of any suitable electrically conductive material as will be evident to a skilled artisan, for example suitable nickel based alloys such as INCONEL. Preferably, device 20 and antenna 24 are incorporated in a TEFLON ring which is positioned in groove 14 and forms a fluid tight seal through which an appropriate radio frequency signal may be transmitted and received.
[0027] A radio frequency transmitter and receiver (i.e. a transceiver) 40 is provided (FIG. 4). Transceiver may be in the form of a hand held portable terminal 42 connected to a hand-held wand 44 by means of cable 43 . In operation, as a tubing string that comprises tubulars joined together, for example by collars, is being moved into position for use, wand 44 may be manually held adjacent the tubulars without regarding for the specific orientation of a responding device on a given tubular. Alternatively, where the process permits, wand 44 may be secured in a stationary position that is adjacent the tubulars and held in that position by any suitable mechanical means as will be evident to a skilled artisan. Transceiver 40 constantly transmits a radio frequency signal in the direction of the tubing string. As antenna 24 on a given collar 10 passes adjacent wand 44 , the signal emanating from wand 44 is received by antenna 24 and transmitted to radio frequency identification device 20 . Device 20 detects this signal and sends a radio frequency response that is transmitted through the antenna 24 so as to be received by transceiver 40 . In this manner, each tubular joint and its position is identified. By using an antenna in accordance with the present invention not only is the orientation of tubulars (and therefor responding devices) as well as the corresponding transceiver irrelevant, but the antenna is able to receive and broadcast radio frequency signals at greater distances than by using only a radio frequency identification device, e.g. up to 15 inches or more with an antenna as compared to 3 inches for an RFID device alone.
[0028] In another embodiment of the present invention that is illustrated in FIG. 2, a bore or hole 11 is provided in collar 10 and a RFID 20 is positioned in bore 11 and is electrically connected to an outer antenna 24 by any suitable means, for example by silver solder or welds 25 . In accordance with the embodiment of FIG. 2, a generally annular inner antenna 26 is positioned in a ring 18 that is provided with screw threads 19 on the outer surface thereof. Threads 19 are mated with threads 12 on collar 10 such that ring 18 is positioned in the gap between the ends 3 , 7 of tubulars 2 , 6 , respectively, as mated with collar 10 . Inner antenna 26 is electrically connected with RFID by any suitable means, for example a silver solder or welds 27 . The operation of this embodiment with respect to use of a transceiver 40 that is positioned outside of the tubulars is identical to that described with respect to FIGS. 1 and 4 above. However, the embodiment of FIG. 2 may also be used in conjunction with a transceiver that is transported through the bores of the tubulars (not illustrated). As thus constructed and assembled, radio frequency signals from transceiver(s) may be received from the exterior of tubulars and adjoining collars by means of outer antenna 24 and/or from the interior of tubulars and adjoining collars by means of inner antenna 26 and information from RFID 20 may be transmitted via antenna 24 to transceiver(s) located external to the tubulars and adjoining collars and/or via antenna 26 to transceiver(s) located internal to the tubulars and adjoining collars. In this manner, information transmission can occur to and/or from the exterior and/or the interior of the tubulars.
[0029] While responding device 20 and antennas 24 and 26 have been described above as connected to a collar 10 , it is within the scope of the present invention to connect responding device 20 and antennas 24 and/or 26 directly to a tubular and/or to tools, equipment and/or devices, especially those used in conjunction with tubulars, in a manner substantially similar with that described above with respect to collar 10 . For tubulars, such direct connection is mandatory where collars are not utilize to secure individual tubulars together as is often the case with drill strings where individual tubulars are connected to each other.
[0030] It is also within the scope of the present invention to utilize a conventional responding device, for example a RFID, without an associated antenna. As illustrated in FIG. 3, a RFID 20 is positioned within a bore or hole 11 formed in the outer surface of collar 10 . A commercially available epoxy is placed in the bore or hole 11 and cured thereby encapsulating RFID device 20 in a fluid tight seal through which an appropriate radio frequency signal may be transmitted and received. In this embodiment, a transceiver 50 is employed which is sized and configured to permit the passage of tubulars therethrough. As illustrated, transceiver 50 is configured in a ring like shape that has an annular groove 51 formed in the inner surface thereof. An antenna 52 for the transceiver is positioned within groove 51 and extends substantially the entire length of the groove. In this embodiment, tubulars equipped with a conventional RFID may be passed through transceiver 50 with the antenna 52 ensuring that radio frequency communication between the transceiver and the RFID occurs without regard to rotational orientation of the tubulars.
[0031] While the use of an antenna in accordance with the embodiments of the present invention has been described herein only in conjunction with tubulars, it will be evident to a skilled artisan that the antenna may be used in conjunction with equipment, tools, and other devices that are secured to tubulars or to any asset that is required to be identified and tracked by use of a transceiver. Examples of such equipment, tools and devices used in conjunction with tubulars used in pipelines, subterranean wells or other fluid transmission lines, are bits, packers, plugs, pigs, valves, landing nipples, profiles, disconnects, ported subs, perforated nipples and polished bore receptacles.
[0032] While the foregoing preferred embodiments of the invention have been described and shown, it is understood that the alternatives and modifications, such as those suggested and others, may be made thereto and fall within the scope of the invention. | An assembly and process for identifying and tracking assets, such as tubulars, equipment, tools and/or devices. An antenna is electrically connected to a responding device, such as a radio frequency identification device, and this assembly is connected to an asset. The antenna may be positioned about the exterior and/or the interior of the asset and significantly increases the range of signals that may be received and/or broadcast by the responding device. A transceiver may accordingly be positioned a greater distance from the asset without regard to the orientation of the asset and still permit communication between the transceiver and the responding device. In this manner, information that specifically identifies the asset may be compiled in a data base so as to maintain an accurate history of the usage of such assets as tubulars, equipment, tool and/or devices. | 4 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation of copending International Application No. PCT/EP99/09793, filed Dec. 10, 1999, which designated the United States.
BACKGROUND OF THE INVENTION
[0002] Field of the Invention
[0003] The invention relates to a refrigerating unit having at least one cooling chamber that is equipped with a storage compartment that is guided in a drawer-like manner and has, at least on its two longitudinal sides lying in the insertion direction, a parallel-guiding device that is formed by a rack-like mating toothed configuration and of two rollers that are coupled at least approximately rigidly to each other. The rollers lie opposite each other at least substantially on the same axis and have an external toothed configuration of identical pitch circle diameter that is able to roll along the mating toothed configuration, in which case either the mating toothed configuration or the rollers are disposed in a positionally fixed manner. European Patent Application EP 07 18 574 A1 discloses a refrigerating unit having a cooling compartment that is equipped with storage compartments that can be pulled out in a drawer-like manner. The larger of the storage compartments supports a door for closing the cooling compartment. The storage compartment that is provided with the door is equipped with a parallel-guiding device. The parallel-guiding device is respectively formed by a rack-like mating toothed configuration provided on the side walls of the cooling compartment and by externally toothed rollers that are provided on the side walls of the storage compartment. The rollers interact with the mating toothed configuration. In such a type of parallel guidance, to avoid an oblique position of the storage compartment arising because the rollers on the storage compartment are not correctly inserted into the mating toothed configuration, a restricted guiding device connected upstream of the mating toothed configuration in the insertion direction of the storage compartment is proposed. The device serves to bring the externally toothed rollers on the storage compartment into engagement with the mating toothed configuration in a movement running at least substantially perpendicularly with respect to the mating toothed configuration. It, therefore, avoids an oblique position during the procedure of inserting the storage compartment into the guides provided in the cooling compartment. In spite of such a measure, it has turned out that if the storage compartment is not correctly maneuvered, misalignment occurs. Specifically, the storage compartment is not prevented from passing into an oblique position in which the externally toothed rollers (rigidly connected to each other per se) move asynchronously with respect to each other during movement of the storage compartment. Also in the oblique position, with the storage compartment in the closed position, a gap arises between its seal and the supporting edge provided for the edge on the housing. Due to the presence of the gap, a rise in temperature of the storage compartment results.
SUMMARY OF THE INVENTION
[0004] It is accordingly an object of the invention to provide a refrigerating unit that overcomes the hereinafore-mentioned disadvantages of the heretofore-known devices of this general type and that is able to correct an oblique position of the storage compartment using simple structural measures.
[0005] With the foregoing and other objects in view, there is provided, in accordance with the invention, a refrigerating unit, including a cooling chamber having two longitudinal sides, a storage compartment removably guided into and out of the cooling chamber in a movement direction, the storage compartment removably guided into the cooling chamber along the movement direction as far as a closing position, the cooling chamber having a parallel-guiding device disposed on the two longitudinal sides along the movement direction, the parallel-guiding device having a mating toothed configuration, two rollers coupled approximately rigidly to each other, lying opposite each other at least substantially on a given axis, and each having an external toothed configuration with an identical pitch circle diameter to be rollingly coupled to the mating toothed configuration, one of the mating toothed configuration and the rollers positionally fixed with respect to the cooling chamber, and an end section reached by the rollers along the movement direction by the closing position of the storage compartment, and a disengagement device for disengaging at least part of the mating toothed configuration from the external toothed configuration of at least one of the two rollers, the disengagement device disposed at the end section and having a disengagement length sufficient to compensate for an oblique positioning of the storage compartment in and counter to the movement direction arising from an offset of the two rollers from one another along the mating toothed configuration.
[0006] The invention provides a device that is capable of disengaging at least one of the mating toothed configurations and the external toothed configuration in engagement therewith of the roller from the roller at its section that is reached by the roller at the end of the closing movement of the storage compartment. At such a position, the length of the disengagement is capable of compensating for at least one oblique position of the storage compartment in and counter to its insertion direction, which oblique position arises as a result of the rollers that are rolling along the mating toothed configurations becoming offset from each other by a tooth pitch.
[0007] With the invention, when the storage compartment is in the closed position, an oblique position, which may be caused, for example, by a shock-like, eccentric application of force to the storage compartment, is automatically compensated for. As a result, the storage compartment door, which is equipped with a seal, always bears tightly against the opening edge of the access opening to the cooling compartment. As such, a formation of a gap between the seal provided on the storage compartment door and the opening edge of the access opening to the cooling compartment is inevitably avoided. And, even if the storage compartment is incorrectly handled, the specified cooling compartment temperature is always reliably ensured with the storage compartment in the closed position. The closure is reliably ensured because, after each closing procedure, the storage compartment is automatically moved from its oblique position into a positionally correct position, in which the door provided on the storage compartment runs at least substantially parallel to the opening edge of the cooling compartment.
[0008] In accordance with another feature of the invention, the storage compartment is removably guided into and out of the cooling chamber as a drawer.
[0009] In accordance with a further feature of the invention, the disengagement device is disposed at the end section and has a disengagement length sufficient to compensate for an oblique positioning of the storage compartment in and counter to the movement direction arising from a tooth pitch offset of the two rollers from one another along the mating toothed configuration.
[0010] In accordance with an added feature of the invention, the disengagement device is a tooth space that is provided on the mating toothed configuration and is disposed at that end section of the mating toothed configuration that is rolled over by the roller at the end of the closing procedure of the storage compartment.
[0011] By the removal of teeth from the mating toothed configuration and, therefore, the provision of a tooth space, an alignment of the storage compartment, which is in an oblique position during the closing procedure, is brought about in a particularly simple manner at the end of the closing procedure. In particular, providing a tooth space means that an oblique position of different extent can also be corrected in a simple manner by the removal of a plurality of teeth from the mating toothed configuration. Moreover, the provision of a tooth space makes it possible to particularly precisely influence the variables (such as tooth module and pitch circle diameter—variables characterizing the external toothed configuration on the roller and determining the extent of the oblique position and, therefore, of the gap arising in the closed position) and therefore to correct the storage compartment, which has originally been set obliquely, with particular positional accuracy. In the event that the mating toothed configuration is produced integrally from a plastic injection molding, a tooth space caused, for example, by the absence of a plurality of teeth can be produced particularly simply.
[0012] In accordance with an additional feature of the invention, the parallel-guiding device has two parts each having the mating toothed configuration for a respective one of the two rollers, each of the mating toothed configurations has teeth with at least one tooth height, the tooth space, and a feeding region for the rollers. The feeding region has teeth with an increasingly rising tooth height at least approximately continuously to a final tooth height and the tooth space is adjoined by the feeding region.
[0013] Thus, in addition to the possibility of being able to compensate for an oblique position of the storage compartment, a particularly jolt-free feeding of the externally toothed rollers from the tooth spaces into the mating toothed configuration is ensured.
[0014] The mating toothed configurations are disposed in a particularly expedient manner if, in accordance with yet another feature of the invention, it is provided that in each case one of the mating toothed configurations is provided on one of the side walls of the cooling chamber where the side walls are disposed in the insertion direction of the storage compartment.
[0015] Mating toothed configurations disposed as such can be disposed in a particularly rigid manner in terms of position and shape. For example, they can be in the form of a U-shaped guide profile that is equipped on one of its limbs with the mating toothed configuration and that is either placed directly onto the side walls or is embedded into the side walls in a recess corresponding to its external contour and is additionally supported there for increasing the dimensional rigidity of the guide profile, by the thermal insulation of the refrigerating unit, which insulation is produced by coating it with foam. In the event that the mating toothed configuration is provided on a limb of a plastic guide profile that is of U-profile-like shape in cross section, the mating toothed configuration can be produced not only in a particularly simple manner with different tooth pitches and tooth sizes, but also can be exchanged at particularly reasonable cost in the event of damage.
[0016] The feeding from the tooth-space region into the mating toothed configuration is configured in a particularly user-friendly manner if, in accordance with yet a further feature of the invention, it is provided that the feeding region for the rollers is mounted downstream in tooth spaces in the pull-out direction of the storage compartment from the cooling chamber.
[0017] In accordance with yet an added feature of the invention, the disengagement device is configured as a sloping plane that pushes the external toothed configuration of the roller, which is acted upon by an energy accumulator, out of engagement with the mating toothed configuration in the axial direction of the roller immediately before its end section that is rolled over by the external toothed configuration of the roller at the end of the closing movement of the storage compartment. In which case, the roller is supported in the cooling chamber by a running surface. Preferably, the energy accumulator is a spring.
[0018] In accordance with yet an additional feature of the invention, the disengagement device is a sloping plane pushing the external toothed configuration out of engagement with the mating toothed configuration in a direction along the given axis immediately before the storage compartment reaches the closing position.
[0019] By the possibility of being able to vary its slope, the sloping plane provides the conditions for being able to undertake the movement of the externally toothed rollers, so as to bring them out of engagement or into engagement with the mating toothed configuration, in a particularly targeted manner in accordance with the existing space conditions.
[0020] In accordance with again another feature of the invention, the energy accumulator provides a force, and the roller is divided substantially perpendicularly with respect to the given axis into a positionally-fixed section having a smooth-faced running surface and an externally-toothed section displaceably mounted with respect to the given axis, in engagement with the mating toothed configuration; and supported on the positionally-fixed section by the energy accumulator, the externally-toothed section to be brought out of engagement with the mating toothed configuration counter to the force by the sloping plane at least immediately before the roller reaches the end section.
[0021] According to a further preferred embodiment of the subject matter of the invention, the roller is divided essentially perpendicularly with respect to its running axis into a positionally fixed section that is equipped with a smooth-faced running surface and an externally toothed section that is mounted displaceably in the axial direction of the roller, is in engagement with the mating toothed configuration and is supported on the positionally fixed section by an energy accumulator. In such a case, the displaceably mounted section is brought out of engagement with the mating toothed configuration counter to the action of the energy accumulator by the sloping plane at least immediately before its end section on the mating toothed configuration. The end section is rolled over at the end of the closing movement of the storage compartment.
[0022] As such, and in conjunction with the sloping plane, a particularly simple and reasonably priced support of the storage compartment is provided in the closed state in which the externally toothed section is disengaged from the mating toothed configuration.
[0023] In accordance with again a further feature of the invention, the externally-toothed section is to be brought out of engagement with the mating toothed configuration counter to the force by the sloping plane at least immediately before the storage compartment reaches the closing position.
[0024] In accordance with a concomitant feature of the invention, a roller of the two rollers has a running surface, the disengagement device is a sloping plane pushing the external toothed configuration out of engagement with the mating toothed configuration in a direction along the given axis approximately before the roller reaches the end section, and the running surface supports the roller in the cooling chamber approximately at the closing position.
[0025] Other features that are considered as characteristic for the invention are set forth in the appended claims.
[0026] Although the invention is illustrated and described herein as embodied in a refrigerating unit, it is, nevertheless, not intended to be limited to the details shown because various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
[0027] The construction and method of operation of the invention, however, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] [0028]FIG. 1 is a diagrammatic, side elevational view of a multi-temperature household cooling unit having two storage compartments disposed one above the other in its cooling chamber according to the invention, with the lower one having externally toothed rollers engaging a mating toothed configuration provided on guide profiles on the side walls of the cooling chamber;
[0029] [0029]FIG. 2 is a perspective view from above of the lower storage of FIG. 1 without a door and with toothed rollers coupled to each other through a spindle, and with one of the guide profiles with the mating toothed configuration having a tooth space for disengaging the roller;
[0030] [0030]FIG. 3 is a fragmentary, cross-sectional view of the heat-insulating housing from above the cooling unit of FIG. 1 in a region of the guide profiles remote from the door;
[0031] [0031]FIG. 4 is a fragmentary, cross-sectional view of the guide rail according to FIG. 3 in the region of the tooth space along the line IV-IV;
[0032] [0032]FIG. 5 is a fragmentary, cross-sectional view of an alternative configuration of one of the guide profiles having a sloping plane for disengaging a toothed wheel in engagement with the mating toothed configuration from the front of the compartment of FIGS. 1 and 3; and
[0033] [0033]FIG. 6 is a fragmentary, cross-sectional view of an alternative configuration of FIG. 5 along the line VI-VI having the toothed wheel disengaged at the end remote from the door by the sloping plane.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0034] In all the figures of the drawing, sub-features and integral parts that correspond to one another bear the same reference symbol in each case.
[0035] Referring now to the figures of the drawings in detail and first, particularly to FIG. 1 thereof, there is shown an illustration of the lower section of a multi-temperature household cooling unit 10 having a heat-insulating housing 11 with external cladding 12 , a heat-insulating layer 13 produced by coating it with foam, and an internal cladding 15 that is formed without cutting and serves for lining a cooling chamber 14 . The internal cladding 15 is provided, on its mutually opposite side walls 16 (only one of which is shown), with guide profiles that are disposed at a distance one above another, that have a U-shaped cross section, and that are inserted into the side walls 16 . FIG. 1 depicts two storage compartments disposed one above the other in the cooling chamber 14 . The guide profile 17 that is disposed lower down in the cooling chamber 14 is provided with a smooth-faced guide track 19 on its U-profile limb 18 , which is disposed lower down when installed. Opposite the guide track 19 , the guide profile 17 has, on its second, higher up limb 20 , a mating toothed configuration 21 that is shaped in the manner of a rack. The inside of the limb 20 facing the guide track 19 is integrally formed on the guide profile 17 and it is manufactured from a plastic injection molding. The mating toothed configuration 21 has, on its end section 22 at the end of the mating toothed configuration 21 , a tooth space 23 that is formed by the absence of one or more teeth 24 of the mating toothed configuration 21 . The end section 22 faces away from the opening side of the cooling chamber 14 . The teeth 24 are disposed directly one behind the other, where, in a tooth module of 1.5 and a pitch circle diameter of 17.5 mm for a toothed wheel described in greater detail further on, a tooth space having a disengagement length L of at least four missing teeth has been tried and tested.
[0036] The mating toothed configuration 21 serves for the parallel guidance of a storage compartment 25 that can be pulled in a drawer-like manner out of the cooling chamber and on whose front side is a heat-insulating door 26 . The heat-insulating door 26 serves to close the cooling chamber 14 and is provided with a magnetic seal 27 around the periphery of its lateral edges facing the cooling compartment 14 . The magnetic seal 27 rests in a sealing manner on the opening edge of the cooling chamber 14 when the door 26 is closed. At the free end of the storage compartment 25 walls that bound the compartment chamber, the storage compartment 25 is equipped with a frame-like surround 28 that is formed from strut-like sections 29 to 31 of which, strut section 29 faces the door 26 and serves to fasten the surround 28 to the storage compartment 25 . Of the other strut sections 30 , 31 , strut sections 30 run parallel to the side walls 16 of the internal cladding 15 , while strut section 31 is provided on that section of the storage compartment 25 that is remote from the door and connects the lateral strut sections 30 to each other, in the same manner as is brought about by that strut section 29 that is near the door.
[0037] As can be seen in particular from FIG. 2, strut section 31 remote from the door has, on its lateral end sections, bearing sockets 32 for the mounting of a bearing spindle 33 that, at least to a very large extent, is twist-proof. See also FIG. 3. At its free end sections that protrude with respect to the bearing sockets 32 , the bearing spindle 33 is provided with a respective flattened portion 34 (see FIG. 4) that interacts in a positive-locking manner with a hub 36 sitting in the center of a roller 35 . By the positive engagement, the rollers 35 that are provided at both ends of the bearing spindle 33 are coupled rigidly to each other in an aligned tooth position through the bearing spindle 33 in a manner secured against twisting. In the exemplary embodiment, the rollers 35 are fixed axially on the bearing spindle at one end by the lateral edges of the transverse strut 31 and are fixed at the other end by securing rings that are provided in the vicinity of the two free end sections of the bearing spindle 33 . The rollers 35 engage in retaining grooves (not illustrated in greater detail and not referred to in greater detail) and are conventionally used for such purposes. See, i.e., FIG. 3.
[0038] As emerges, in particular, from FIG. 3, the rollers 35 that are supported on the bearing spindle 33 in a manner secured against twisting and are configured as a stepped circular cylinder are divided on their circumferential surface 37 into two sections that differ in width. The sections correspond essentially to the width of the rollers 35 and of which a relatively narrow section disposed adjacent to the lateral edges of the strut section 31 is equipped with a smooth-faced tread 38 . Directly adjacent to the section provided with the smooth-faced tread 38 , the roller 35 has a second section that is wider, that springs back radially with respect to the first section, and that has on its circumferential surface an external toothed configuration 39 equipped with the same number of teeth and same tooth module for both rollers 35 . See also FIG. 4.
[0039] [0039]FIG. 1, in particular, shows, for parallel guidance of the storage compartment 25 (moveable in a drawer-like manner in the direction of the double arrow B), the external toothed configuration 39 in engagement with the mating toothed configuration 21 provided on the upper limb 20 of the guide profile 17 . When the storage compartment 25 is moved in the direction of the double arrow B, the smooth-faced tread 38 of the roller 35 rolls along the guide track 19 of the lower limb to support the storage compartment 25 at its end that is remote from the door, and, together with a respective roller 40 (shown in dashed lines), forms a type of roller pull-out for the storage compartment 25 . Roller 40 is disposed in a positionally-fixed manner on the opening edge of the cooling chamber 14 , is supported on the lower side of the lateral strut sections 30 , and is smooth-faced on its circumferential side.
[0040] If the storage compartment 25 is in its state that is illustrated in FIG. 2, in which it is inserted into the cooling chamber 14 , then the external toothed configuration 39 of one of the rollers 35 is disengaged from the mating toothed configuration 21 because of the tooth space 23 (provided on the end section 22 remote from the door on the mating toothed configuration 21 assigned to the roller 35 ). Such disengagement ensures that the magnetic seal 27 bears on all sides against the opening edge of the cooling chamber 14 when the door 26 is in the closed state. Even if, during the procedure of inserting the cooling compartment 25 into the cooling chamber 14 , an oblique position of the storage compartment 25 is caused by one of the externally toothed rollers 35 running ahead due to an improper, eccentric and simultaneously shock-like application of force to the door 12 , the oblique position is corrected again when the door is in the closed state. Such correction takes place as a result of the tooth space 23 on one of the mating toothed configurations 21 enabling the oblique position to be eliminated and tight bearing of the magnetic seal 17 against the opening edge of the cooling chamber 14 to be produced.
[0041] [0041]FIG. 5 shows an alternative embodiment of one of the guide profiles 50 . The guide profile 50 is sitting in a hollow of the internal cladding 15 on the side walls 16 . Like the guide profile 17 , the guide profile 50 , which is fixed to the two side walls 16 of the internal cladding 15 , is substantially a U-profile in cross section. Such U-profile is equipped in the fitted position with a smooth-faced guide track 52 provided on the inside of its lower-disposed limb 51 . Furthermore, when fitted, the guide profile 50 is provided, on its higher-disposed limb 53 , with a mating toothed configuration 54 . The mating toothed configuration 54 is configured as a rack, is disposed virtually over the entire length of the guide profile 50 , and is provided directly adjacent to a base that connects the two limbs 51 and 53 and serves as a back wall 55 facing the heat insulation 13 . On the end section 56 of the back wall 55 , which is disposed opposite the opening of the cooling chamber 14 , the back wall 55 is provided with a sloping plane 57 (see FIG. 6, in particular) that is integrally formed on the back wall 55 and that extends from a starting point A within the end section 56 obliquely over the mating toothed configuration 54 to the free end of the end section 56 .
[0042] The mating toothed configuration 54 (provided on each of the two guide profiles 50 ) serves for the parallel guiding of a storage compartment 58 that has a similar configuration as that of the storage compartment 25 . The compartment 58 is only shown in part in FIG. 6 and can be moved in a drawer-like manner out of the cooling compartment 14 in the direction of the double arrow B. Like the storage compartment 25 , compartment 58 is provided with a frame-like surround 59 on its opening edge. The surround 59 is formed from a plurality of strut sections. The strut sections include two laterally extending struts 60 produced by the internal gas pressure method, a non-illustrated strut on the front side, and a transverse strut 61 that is remote from the door and connects the lateral struts 60 to each other on their rear section remote from the door. The transverse strut 61 is equipped at its two lateral end sections with a bearing socket 62 (see FIG. 6) for mounting a bearing spindle 63 that has a twist-proof configuration at least to a very large extent. The spindle 63 is mounted rotatably in the bearing sockets 62 and is fixed in the axial direction with respect to the bearing sockets by a non-illustrated fixing device. The bearing spindle 63 has end sections 64 that protrude with respect to the lateral edges of the bearing sockets 62 and on which a roller 65 is fixed. The roller 65 is disposed adjacent to the lateral edges of the bearing socket 62 . The roller 65 is a circular cylinder, is divided perpendicularly and with respect to its axial direction and has a first section 65 . 1 that is equipped on its circumferential side with a smooth-faced tread 66 . On a side of the section 65 . 1 facing the bearing socket 62 , the section 65 . 1 is supported axially in the axial direction by a resilient securing washer 67 that engages in a groove. Another side of the section 65 . 1 that lies opposite the first side serves to support a compression spring 68 that is provided as an energy accumulator and is resiliently supported by one of its free ends 69 on the section 65 . 1 and by its other free end 70 on a second section 71 of the roller 65 . The second section 71 is configured as a toothed wheel provided with an external toothed configuration 71 . 1 . The second section 71 is mounted on the bearing spindle 63 both in a manner such that it can be displaced in the axial direction of the bearing spindle 63 and also in a manner such that it is secured against twisting. For the displaceable mounting of the section 71 , it has a hub 72 that sits in its center and is provided on its circumferential side with a groove 73 that extends in its axial direction and in which an adjusting spring 74 , which is fixed on the end section 64 , engages in a positive-locking manner. The displacement path of the section 71 towards the free end of the end section 64 is limited by a resilient securing washer 75 that is placed there in a positive-locking manner. In addition to the two-part roller 65 , a roller as used in accordance with the first embodiment of the invention, for example, is provided on the second end section 64 of the bearing spindle 63 .
[0043] If the storage compartment is moved from its open position (see FIG. 1) in which the section 71 engages with its external toothed configuration 71 . 1 in the mating toothed configuration 54 ) and then into the cooling chamber 14 , the section 71 is pushed by the sloping plane 57 at the end of the insertion path out of engagement with the mating toothed configuration 54 by the sloping plane 57 that is disposed on the guide profile 50 that faces the section 71 . As a result, an oblique position of the storage compartment 58 is corrected by the disengagement (the oblique position possibly arising because of an improper procedure of inserting the storage compartment 58 ). Thus, the magnetic seal 27 of the door 26 provided at the front end of the storage compartment 58 sealingly rests on all sides against the opening edge of the cooling chamber 14 . | A refrigerating unit includes a cooling chamber, a storage compartment removably guided within the chamber as far as a closing position, and a disengagement device. The chamber has a parallel-guide disposed on its sides. The guide has a mating toothed configuration, two rollers rigidly coupled, lying opposite each other, and each having an external toothed configuration with a pitch circle diameter to be rollingly coupled to the mating toothed configuration. The guide has an end section reached by the rollers near the closing position. One of the mating toothed configuration and the rollers is positionally fixed. The disengagement device disengages the mating toothed configuration from the external toothed configuration of the rollers and is at the end section and has a disengagement length compensating for oblique positioning of the compartment in and counter to a movement direction arising from an offset of the rollers along the mating toothed configuration. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Application No. 61/332,117, filed May 6, 2010, which application is hereby incorporated herein by reference, in its entirety.
TECHNICAL FIELD
[0002] The invention relates generally to financial reporting and, more particularly, to a system and method for re-using XBRL-tags for financial reporting across time period boundaries.
BACKGROUND
[0003] A typical filer of financial reports will submit multiple quarterly reports (one per quarter, also known as 10Q reports), and one annual report (one per year, also known as 10K reports or 20F reports). Conventional filers prepare and submit such reports multiple times a year in a form called Edgarized HTML (referred to herein as “HTML report”). These financial reports are typically relatively large documents (often ranging in length from 50 to over 100 pages, depending on complexity) containing information about financial statements, notes, management discussion, analysis, and other related information as required by the Securities and Exchange Commission (“SEC”).
[0004] Extensible Business Reporting Language (“XBRL”) is a technology standard that can be applied to the creation of financial statement data and other reporting situations. XBRL is an application of Extensible Markup Language (“XML”) to business information and it uses tags or structure to describe the data, making it immediately reusable, interactive and intelligent. It is also “extensible” so it can be customized for unique situations and reporting concepts.
[0005] For regulators and accountants, XBRL allows financial information to be uniquely identified using a tag. Once an item or piece of financial information is tagged, it can be used consistently throughout various and diverse reports that contain that particular item or piece of financial information.
[0006] For investors, XBRL pinpoints all of the facts and figures trapped in current financial documents, allowing investors to immediately pull out exactly the information they want, and instantly compare it to the results of other companies.
[0007] XBRL is a royalty-free technology developed and maintained by XBRL International, a not-for-profit consortium comprising over 800 accounting, technology, financial services, and regulatory-type organizations across the world. In addition, every local jurisdiction (e.g., a specific geographical region or country) develops and maintains taxonomies which are specific to that jurisdiction's scenario. For example XBRL US developed and maintains the US GAAP taxonomy.
[0008] The SEC has mandated required reporting in the XBRL for registrants other than investment companies subject to a three-tier phased-in program beginning with fiscal periods ending on or after Jun. 15, 2009. The three tiers of the SEC Mandate Timeline are:
[0009] Tier 1: Domestic and foreign large accelerated filers that file financial statements presented in accordance with U.S. GAAP and have a worldwide public float above $5 billion as of the end of the second fiscal quarter of their most recently completed fiscal year, beginning with the first fiscal period ending on or after Jun. 15, 2009.
[0010] Tier 2: All other domestic and foreign large accelerated filers that file financial statements prepared in accordance with U.S. GAAP, beginning with the first fiscal period ending on or after Jun. 15, 2010.
[0011] Tier 3: All remaining filers that file financial statements prepared in accordance with U.S. GAAP, including smaller reporting companies, and all foreign private issuers that prepare their financial statements in accordance with IFRS as issued by the LAS B, beginning with the first fiscal period ending on or after Jun. 15, 2011.
[0012] In Phase 1 (referred to herein as “Year 1”), filers are expected to tag all numbers in their face financials as well as block tag (putting one tag against the complete note) all the Notes to Financial Statements. In Phase 2 (referred to herein as “Year 2”), filers are expected to additionally tag (1) each significant accounting policy within the significant accounting policies footnote tagged as a single block of text; (2) each table within each footnote tagged as a separate block of text; and (3) within each footnote, each amount (i.e., monetary value, percentage, and number) separately tagged.
[0013] It is expected that filers will have about 300-400 pieces of information to be tagged in Year 1. In Year 2 it is expected that filers will have to tag about 2,000-3,000 pieces of information. So as can be seen there is a significant increase in the number of tags from Year 1 to Year 2. In addition to the increase in tagging complexity and effort, filers are expected to file the XBRL version of their financial reports on the same-day as the HTML version of the financial reports.
[0014] While the foregoing exemplifies a US-based public company corporate filing, the challenges described apply to XBRL-based reporting scenarios world-wide.
[0015] Filers can comply, leveraging three kinds of solutions, namely, a bolt-on approach, an outsourced approach, and an embedded approach.
[0016] In the “bolt-on” approach, organizations use a standalone tool which reads Excel/Word documents and provides a XBRL-only tagging solution. Since these are built as general purpose tagging tools they fail to incorporate the financial reporting context when performing the tagging. In addition some of them require re-tagging every period which can be cumbersome with a large number of tags.
[0017] By outsourcing, customers rely on the external service provider to handle the XBRL tagging. While this can work well for the initial tagging requirements in the first year; however, given the ramp-up of XBRL requirements in the second year, these organizations may find themselves at a disadvantage because they have outsourced their XBRL capabilities and thus have not built up expertise in the application and use of XBRL. In addition, outsourcing costs can be significant as well.
[0018] In the embedded approach, XBRL tagging becomes just another capability, and the tagging features are embedded inside the financial report preparation process, thereby providing a more integrated experience to the end-user.
[0019] In the light of above requirements, particularly the large number of tags and the requirement for same-day filing, there is a need for a tagging solution where the majority of the tagging-related constructs can be setup once and tags can be rolled forward every period.
SUMMARY
[0020] The present invention, accordingly, provides an XBRL tag which is re-usable across period boundaries, the tag including at least one definitional attribute and at least one transactional attribute, wherein the at least one transactional attribute is updated for each period.
[0021] The foregoing has outlined rather broadly the features and technical advantages of the present invention in order that the detailed description of the invention that follows may be better understood. Additional features and advantages of the invention will be described hereinafter which form the subject of the claims of the invention. It should be appreciated by those skilled in the art that the conception and the specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present invention. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the invention as set forth in the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] For a more complete understanding of the present invention, and the advantages thereof, reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which:
[0023] FIG. 1 is a schematic diagram of a tag embodying features of the present invention; and
[0024] FIG. 2 is a schematic diagram of the tag of FIG. 1 defined once and updated for a subsequent period in accordance with principles of the present invention.
DETAILED DESCRIPTION
[0025] The following description is presented to enable any person skilled in the art to make and use the invention, and is provided in the context of a particular application and its requirements. Various modifications to the disclosed embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments and applications without departing from the spirit and scope of the present invention. Thus, 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 disclosed herein. Additionally, as used herein, the term “substantially” is to be construed as a term of approximation.
[0026] In the discussion of the FIGURES, the same reference numerals will be used throughout to refer to the same or similar components.
[0027] It is noted that, unless indicated otherwise, all functions described herein may be performed by a processor such as a microprocessor, a controller, a microcontroller, an application-specific integrated circuit (ASIC), an electronic data processor, a computer, or the like, in accordance with code, such as program code, software, integrated circuits, and/or the like that are coded to perform such functions. Furthermore, it is considered that the design, development, and implementation details of all such code would be apparent to a person having ordinary skill in the art based upon a review of the present description of the invention.
[0028] Referring to FIG. 1 of the drawings, the reference numeral 100 generally designates a XBRL, tag having multiple pieces of data (referred to herein as “attributes”) which need to be filled-in. The illustration below shows how a number reported in the balance sheet gets translated into XBRL.
[0029] The element or tag 102 is the name of the tag as represented in the taxonomy.
[0030] The value 104 is the completely scoped value being reported.
[0031] The number of decimals or precision 106 provides information on rounding and precision of numbers in the value 104 .
[0032] The units 108 for the number being reported, such as, by way of example, U.S. dollars (“USD”).
[0033] The period 110 represents the date(s) for which content is being reported.
[0034] The entity 112 is the name of the filing entity.
[0035] The footnotes 114 could be any kind of “superscript footnotes” against the reported number.
[0036] The dimensions 116 indicate the level or granularity of the filing entity. For example, the level of the content being reported could be at the level of the filing entity or at a more granular level, such as a geographical region.
[0037] As mentioned above, a single number/content on an HTML report can translate into many attributes on a tag, some of which attributes generally do not change during subsequent periods, and some of which attributes do change during subsequent periods.
[0038] Within financial reports, there are constructs which are independent of the period and those which are specific to a period. For example, the actual structure of a financial report (like the line items within a balance sheet) remains largely the same but the actual values and dates vary on a per period basis. Hence there are really two kinds of constructs involved, namely, templates and instances.
[0039] Templates contain the overall structure, outline, and thinks anything that doesn't vary by period. By way of example, a 10Q template. A technical term for anything defined in the template is also referred to herein as “definitional”. The template comprises the following parts of the tag, namely, choosing the element 102 , setting units 108 , setting the precision 106 , setting dimensions 116 , setting relative period (discussed in further detail below). It is noted that the user may “override” tag attributes set in the template (for addressing corner cases).
[0040] And instance contains a “period specific variation” of that template. By way of example, a 10Q for the period ending Dec. 31, 2010. A technical term for anything defined in the instance itself is also referred to herein as “transactional”. The instance comprises the following parts of the tag, namely, setting values (attribute 104 ) and changing period values (attribute 110 ) as required. Values are brought in any way as part of the financial reporting process so there is nothing special for XBRL tags.
[0041] Unity Xtensible Financial Reporting (“XFR”, a Trintech® technology which automates complex financial reporting processes) embraces this sort of strategy, so that meta-data can be defined once and re-used over and over again every period. Building on that strategy for XBRL tagging, there are some attributes of the tag which belong in the template and some attributes which belong in the instance itself. Some attributes will overlap between the template and an instances.
[0042] The strategy for periods requires further explanation. Since there can be a lot of period data within a financial report (and hence within the XBRL tagged document), there is a need for allowing users to setup “relative periods” once in the template setup, but also allow for actual date values to be automatically populated based on a handful of dates which change every period. As most financial reports are analyzed, there are a handful of actual date variations which are re-used across reporting periods. With reference to the following table, by way of example, the “Current reporting period” is a construct which can be used when setting up the tags in the template, but actual values will vary every period. So there may be hundreds of actual dates in the report, but the user only has to choose one of the relative periods for tagging in the template and specify period specific dates only for the use. The system of the invention would automatically populate date-specific tag attributes for all of them.
[0000]
Relative
Q example
K example
Period Type
Start Period
End Period
Start Period
End Period
Current reporting period
7/1/2009
9/30/2009
1/1/2009
12/31/2009
Previous reporting period
4/1/2009
6/30/2009
1/1/2008
12/31/2008
(Y-1) reporting period
7/1/2008
9/30/2008
1/1/2008
12/31/2008
Current YTD
1/1/2009
9/30/2009
1/1/2009
12/31/2009
Previous YTD
1/1/2008
9/30/2008
1/1/2008
12/31/2008
Current fiscal year
1/1/2009
12/31/2009
1/1/2009
12/31/2009
Previous Fiscal year
1/1/2008
12/31/2008
1/1/2008
12/31/2008
[0043] With reference to FIG. 2 , in the operation of the invention, the tag 200 includes template attributes 106 , 108 , 112 , 114 , and 116 which remain substantially constant from one period to another period. Instance attributes 104 and 110 are the only attributes that change from one period to the next. As shown in FIG. 3 , the attributes 104 and 110 of the tag 300 are reviewed and updated with content in a new period, which content may change in each subsequent period.
[0044] By the use of the present invention, users can setup a substantial amount of tag-specific information once (or even less frequently) within a template, and the system of the invention would roll-forward all such tagging information every period without a large amount of manual work every period.
[0045] Having thus described the present invention by reference to certain of its preferred embodiments, it is noted that the embodiments disclosed are illustrative rather than limiting in nature and that a wide range of variations, modifications, changes, and substitutions are contemplated in the foregoing disclosure and, in some instances, some features of the present invention may be employed without a corresponding use of the other features. Many such variations and modifications may be considered obvious and desirable by those skilled in the art based upon a review of the foregoing description of preferred embodiments. Accordingly, it is appropriate that the appended claims be construed broadly and in a manner consistent with the scope of the invention. | An XBRL tag re-usable across period boundaries includes at least one definitional attribute and at least one transactional attribute, wherein the at least one transactional attribute is updated for each period. | 6 |
This application is the National Stage of International Application No. PCT/EP2005/002177, filed Mar. 2, 2005, which claims the benefit of European Application No. 04004950.4, filed Mar. 3, 2004, which is hereby incorporated by reference in its entirety.
The invention relates to a method for the purification of the N-terminal four kringle-containing fragment of hepatocyte growth factor (NK4).
BACKGROUND OF THE INVENTION
Hepatocyte growth factor (HGF/SF) is a polypeptide identified and purified by Nakamura, T., et al., Biochem. Biophys. Res. Commun. 22 (1984) 1450-1459. It was further found that hepatocyte growth factor is identical to scatter factor (SF), Weidner, K. M., et al., Proc. Natl. Acad. Sci. USA 88 (1991) 7001-7005. HGF is a glycoprotein involved in the development of a number of cellular phenotypes including proliferation, mitogenesis, formation of branching tubules and, in the case of tumor cells, invasion and metastasis. For a status review, see Stuart, K. A., et al., Int. J. Exp. Pathol. 81 (2000) 17-30.
Both rat HGF and human HGF have been sequenced and cloned (Miyazawa, K. et al., Biochem. Biophys. Res. Comm. 163 (1989) 967-973; Nakamura, T., et al., Nature 342 (1989) 440-443; Seki, T., et al., Biochem. and Biophys. Res. Comm. 172 (1990) 321-327; Tashiro, K., et al., Proc. Natl. Acad. Sci. USA 87 (1990) 3200-3204; Okajima, A., et al., Eur. J. Biochem. 193 (1990) 375-381).
It was further found that an HGF/SF fragment, termed NK4, consisting of the N-terminal hairpin domain and the four kringle domains of HGF/SF has pharmacological properties that are completely different from those of HGF/SF, and is an antagonist to the influence of HGF/SF on the motility and the invasion of colon cancer cells, and is, in addition, an angiogenesis inhibitor that suppresses tumor growth and metastasis (Parr, C., et al., Int. J. Cancer 85 (2000) 563-570; Kuba, K., et al., Cancer Res. 60 (2000) 6737-6743; Date, K., et al., FEBS Lett. 420 (1997) 1-6; Date, K., et al., Oncogene 17 (1989) 3045-3054).
NK4 is prepared according to the state of the art (Date, K., et al., FEBS Lett. 420 (1997) 1-6) by recombinant expression of HGF cDNA in CHO cells and subsequent digestion with pancreatic elastase. Two other isoforms of HGF (NK1 and NK2) encoding the N-terminal domain and kringle 1, and the N-terminal domain and kringles 1 and 2, respectively, were produced in E. coli via the inclusion body route (Stahl, S. J., Biochem. J. 326 (1997) 763-772). According to Stahl, naturation of NK1 or NK2 was performed in 100 mM TRIS/HCl pH 7.5 containing 2.5 M urea, 5 mM reduced glutathione (GSH) and 1 mM oxidized glutathione (GSSG). Purification was performed subsequently on a Superdex™ 75 column using also TRIS buffer. The use of TRIS buffer according to the state of the art during solubilization and naturation leads according to the investigations of the inventors to a considerable amount (of about 50%) of by-products which are identified by the inventors as consisting mainly of GSH-modified NK4.
Therefore this method is not useful for the recombinant production of NK4 in considerable amounts and sufficient purity (for therapeutic use).
SUMMARY OF THE INVENTION
The invention provides a method for the production of NK4 by expression of a nucleic acid encoding said NK4 in a microbial host cell, isolation of inclusion bodies containing said NK4 in denatured form, solubilization of the inclusion bodies and naturation of the denatured NK4 in the presence of GSH and GSSG, characterized in that solubilization and naturation are performed at pH 7-9 in phosphate buffered solution.
It was surprisingly found that the use of potassium phosphate buffer in a pH range between 7 and 9, preferably between pH 8 and 9, leads to a considerable improvement in yield and purity of NK4.
Preferably NK4 is dialyzed after naturation with phosphate buffer pH 7-9 for at least 24 hours. Purificaton is performed preferably by hydrophobic interaction chromatography in the presence of phosphate buffer pH 7-9, whereby the use of butyl- or phenyl sepharose as chromatographic material is especially preferred.
DETAILED DESCRIPTION OF THE INVENTION
Human HGF is a disulfide-linked heterodimer, which can be cleaved in an α-subunit of 463 amino acids and a β-subunit of 234 amino acids, by cleavage between amino acids R494 and V495. The N-terminus of the α-chain is preceded by 31 amino acids started with a methionine group. This segment includes a signal sequence of 31 amino acids. The α-chain starts at amino acid 32 and contains four kringle domains. The so-called “hairpin domain” consists of amino acids 70-96. The kringle 1 domain consists of amino acids 128-206. The kringle 2 domain consists of amino acids 211-288, the kringle 3 domain consists of amino acids 305-383, and the kringle 4 domain consists of amino acids 391-469 of the α-chain, approximately.
NK4 according to the invention consist preferably of amino acid (aa) 32-494 or an N-terminal fragment thereof (always beginning with aa 32), the smallest fragment being aa 32-478. The length of NK4 can vary within this range as long as its biological properties are not affected. In addition there exist variations of these sequences, essentially not affecting the biological properties of NK4 (especially not affecting its activities antagonistic to HGF and its antiangiogenic activities), which variations are described, for example, in WO 93/23541. The activity of NK4 is measured by a scatter assay according to example 4.
NK4 can be produced recombinantly, either by the production of recombinant human HGF/SF and digestion with elastase (Date, K., FEBS Lett. 420 (1997) 1-6) or by recombinant expression of an NK4 encoding nucleic acid in appropriate host cells, as described below. NK4 glycoprotein has a molecular weight of about 57 kDa (52 kDa for the polypeptide part alone) and has the in vivo biological activity of causing inhibition of tumor growth, angiogenesis and/or metastasis.
The NK4 polypeptides can be produced by recombinant means in prokaryotes. For expression in prokaryotic host cells, the nucleic acid is integrated into a suitable expression vector, according to methods familiar to a person skilled in the art. Such an expression vector preferably contains a regulatable/inducible promoter. The recombinant vector is then introduced for the expression into a suitable host cell such as, e.g., E. coli and the transformed cell is cultured under conditions which allow expression of the heterologous gene. After fermentation inclusion bodies containing denatured NK4 are isolated.
Escherichia, Salmonella, Streptomyces or Bacillus are for example suitable as prokaryotic host organisms. For the production of NK4 polypeptides prokaryotes are transformed in the usual manner with the vector, which contains the DNA coding for NK4 and subsequently fermented in the usual manner. However expression yield in E. coli using the original NK4 DNA sequence (GenBank M73239) is very low. Surprisingly it was found that modification of at least one of the codons of the DNA sequence encoding amino acid positions 33 to 36 (codon 33 encodes arginine, numbering according to M73239) results in an increase of expression yield of 20% polypeptide or more. Therefore, a further object of the invention is a method for the recombinant production of NK4 in prokaryotes by expression of a replicable expression vector containing DNA encoding NK4 characterized in that in said DNA at least one of the codons of amino acids selected from the group consisting of codons at positions 33, 34, 35 and 36 is modified from AGG to CGT (position 33), AAA to AAA (position 34), AGA to CGT (position 35), and/or AGA to CGT (position 36). It is further preferred that the codon for amino acid 32 is changed from encoding Gln to encoding Ser in order to improve splitting off N-terminal arginine.
Inclusion bodies are found in the cytoplasm as the gene to be expressed does not contain a signal sequence. These inclusion bodies are separated from other cell components, for example by centrifugation after cell lysis.
The inclusion bodies were solubilized by adding a denaturing agent like 6 M guanidinium hydrochloride or 8 M urea at pH 7-9 in phosphate buffer (preferably in a concentration of 0.1-1.0 M, e.g. 0.4 M) preferably in the presence of DTT (dithio-1,4-threitol). The solubilisate is diluted in phosphate buffer pH 7-9 in the presence of GSH/GSSG (preferably 2-20 mM glutathion) and a denaturing agent in a non denaturing concentration (e.g. 2M guanidinium hydrochloride or 4 M urea) or preferably instead of guanidinium hydrochloride or urea, arginine in a concentration of about 0.3 to 1.0 M, preferably in a concentration of about 0.7 M. Renaturation is performed preferably at a temperature of about 4° C. and for about 48 to 160 hours.
After naturation is terminated the solution was dialyzed preferably against phosphate buffer pH 7-9 (preferably in a concentration of 0.1-1.0 M, e.g. 0.3 M) for at least 24 hours, preferably for 24-120 hours.
NK4 polypeptide or fragments thereof can be purified after recombinant production and naturation of the water insoluble denatured polypeptide (inclusion bodies) according to the method of the invention preferably by chromatographic methods, e.g. by affinity chromatography, hydrophobic interaction chromatography, immunoprecipitation, gel filtration, ion exchange chromatography, chromatofocussing, isoelectric focussing, selective precipitation, electrophoresis, or the like. It is preferred to purify NK4 polypeptides by hydrophobic interaction chromatography, preferably at pH 7-9, in the presence of phosphate buffer and/or preferably by the use of butyl- or phenyl sepharose.
According to the method of the invention, only a minor amount of the NK4 polypeptides is modified by the formation of GSH adducts. Of the total amount of NK4 polypeptides, i.e. the amount of the inclusion bodies separated from other cell components (corresponding to 100%), the amount of GSH-modified NK4 is between 0% and 50%, preferably between 0% and 35%, and more preferably between 0% and 20%.
The following examples, references, sequence listing and figures are provided to aid the understanding of the present invention, the true scope of which is set forth in the appended claims. It is understood that modifications can be made in the procedures set forth without departing from the spirit of the invention.
DESCRIPTION OF THE FIGURES
FIG. 1 Renaturation kinetics, heparin column, detection at 280 nm
FIG. 2 Renaturation efficacies
DESCRIPTION OF THE SEQUENCES
SEQ ID NO:1 DNA coding for NK4
SEQ ID NO:2 Polypetide sequence of NK4
EXAMPLE 1
Recombinant Expression of NK4
The NK4 domain from amino acid position 32 to 478 of HGF was used for cloning and recombinant expression in Escherichia coli. The original DNA sequence used as source of DNA was described (database identifier “gb:M73239”). PCR was performed in order to amplify and concurrently modify the DNA coding for NK4 (Seq ID No:1). All methods were performed under standard conditions.
In comparison to the original DNA sequence of NK4, the following modifications were introduced:
Elimination of the eukaryotic signal peptide sequence and fusion of the ATG start codon next to amino acid position 32 of NK4 exchange of amino acid position 32 from Gln to Ser in order to improve homogeneity of the protein product (Met-free) modification of the DNA sequence of the codons of amino acids at position 33 (AGG to CGT), 35 (AGA to CGT), and 36 (AGA to CGT) in order to improve gene expression in E. coli. modification of the DNA sequence of codons at position 477 (ATA to ATC) and 478 (GTC to GTT) in order to facilitate insertion of PCR product into the vector introduction of two translational stop codons at positions 479 (TAA) and 480 (TGA), in order to stop the translation at a position equivalent to the end of NK4 protein domain.
The PCR-amplified DNA fragment was treated with restriction endonucleases NdeI and BanII and was ligated to the modified pQE vector (Qiagen) (elimination of His-tag as well as DHFR coding region), which was appropriately treated with NdeI and BanII. The elements of expression plasmid pQE-NK4-Ser (Plasmid size 4447 bp) are T5 promotor/lac operator element, NK4 coding region, lambda to transcriptional termination region, rrnB T1 transcriptional termination region, ColE1 origin of replication and β-lactamase coding sequence.
The ligation reaction was used to transform E. coli competent cells, e.g. E. coli strain C600 harbouring expression helper plasmid pUBS520 (Brinkmann, U., et al., Gene 85 (1989) 109-114). E. coli colonies were isolated and were characterized with respect to restriction and sequence analysis of their plasmids. The selection of clones was carried out by analysis of the NK4 protein content after cultivation of recombinant cells in LB medium in the presence of appropriate antibiotics and after induction of the gene expression by addition of IPTG (1 mM). The protein pattern of cell lysates were compared by PAGE. The recombinant E. coli clone showing the highest proportion of NK4 protein was selected for the production process. Fermentation was performed under standard conditions and inclusion bodies were isolated.
EXAMPLE 2
Solubilization and Naturation Using the Optimized Conditions
Inclusion bodies were dissolved over night in a buffer containing 6 M guanidinium hydrochloride, 0.1 M potassium phosphate pH 8.5 (by titration with 10 M KOH), 1 mM EDTA, 0.01 mM DTT. The concentration of the dissolved protein was determined by Biuret assay and finally adjusted to a concentration of 25 mg total protein/ml at room temperature.
This NK4-solubilisate was diluted to a concentration of 0.4 mg/ml in a buffer containing 0.7 M arginine, 0.1 M potassium phosphate pH 8.5 (by titration with conc. HCl), 10 mM GSH, 5 mM GSSG and 1 mM EDTA. This renaturation assay was incubated between 2 and 8 days at 4° C. The renaturation efficacy was measured by analytical affinity chromatgraphy using an 1 ml Heparin Sepharose column (renaturation kinetics see FIG. 1 ).
Buffer conditions:
Buffer A:
50 mM Tris pH 8.0
Buffer B:
50 mM Tris pH 8.0, 2 M NaCl
Gradient:
5-25%
buffer B, 2 column volumes
25-60%
buffer B, 16 column volumes
60-100%
buffer B, 0.7 column volumes
100%
buffer B, 2 column volumes
After obtaining the maximal renaturation efficacy, the renaturation assay of 15 l volume was concentrated to 3 l using a tangential flow filtration unit (MW cut off: 10 kDa, Sartorius). It was subsequently dialyzed against 3 times 50 l buffer containing 0.3 M potassium phosphate at pH 8.0 for at least 3×24 hours, optimally for 5 days in total.
Purification was performed by heparin-sepharose chromatography (conditions see above). To the eluted material 1 M ammonium sulfate in 0.1 M potassium phosphate pH 8.0 was added and incubated at 4° C. overnight. The sample was centrifuged and the supernatant was loaded on a phenyl sepharose column (150 ml). The column was washed with 1 column volume 1 M ammonium sulfate in 50 mM potassium phosphate pH 8.0.
Elution conditions:
Buffer A: 1 M ammonium sulfate, 50 mM potassium phosphate pH 8.0
Buffer B: 50 mM potassium phosphate pH 8.0, 40% ethylene glycol 0-100% buffer B, 20 column volumes
EXAMPLE 3
Comparison of Naturation Using Potassium Phosphate and Tris
Renaturation conditions were analyzed using potassium phosphate or TRIS at pH 7.5 and pH 8.5 (both titrated with conc. HCl) as buffering reagents. The solubilization and renaturation conditions were as described in example 2, but with 0.1 M TRIS or 0.1 M potassium phosphate in the renaturation buffer. The dialysis was also performed as described in example 2, but in 0.1 M TRIS or 0.1 M potassium phosphate. Potassium phosphate buffer (K-P) led to significantly higher renaturation yields as TRIS buffer, measured as amount of active NK4 by scatter assay (see FIG. 2 ).
EXAMPLE 4
Determination of Activity
a) Scatter Assay
MDCK cells were subconfluently grown in tissue culture plates. Cells were treated with HGF (10 ng/ml) or with combinations of HGF and NK4. In these experiments the HGF-induced cell scattering was inhibited by the addition of a 10 to 1000-fold molar excess of NK4 at least for 90% and more, showing the functional activity.
b) Proliferation Assay
Inhibition of the mitogenic activity of HGF by NK4 was determined by measuring DNA synthesis of adult rat hepatocytes in primary culture as described in Nakamura, T., et al., Nature 342 (1989) 440-443. In these experiments the HGF-induced cell proliferation was inhibited by the addition of a 10 to 1000-fold molar excess of NK4 at least for 90% and more, showing the functional activity.
c) Invasion Assay
In this assay the invasive potential of tumor cells is analyzed. The assay was done essentially as described in Albini, A., et al., Cancer Res. 47 (1987) 3239-3245, using HT115 cells. Again, HGF-induced (10 ng/ml) cell invasion could be inhibited by a 10 to 1000-fold molar excess of NK4 at least for 90% and more, showing the functional activity.
EXAMPLE 5
Activity in Vivo
Model: Lewis Lung Carcinoma nude mouse tumor model
1×10 6 lewis lung carcinoma cells were s.c. implanted into male nude mice (BALB/c nu/nu).
Treatment: After 4 days, one application daily of pegylated NK4 over a period of 2-4 weeks
Dose: 1000 μg/mouse/day
300 μg/mouse/day 100 μg/mouse/day placebo
Result: Treatment with NK4 shows a dose dependent suppression of primary tumor growth and metastasis, whereas no effect is seen in placebo treated groups.
LIST OF REFERENCES
Albini, A., et al., Cancer Res. 47 (1987) 3239-3245
Brinkmann, U., et al., Gene 85 (1989) 109-114
Date, K., et al., FEBS Lett. 420 (1997) 1-6
Date, K., et al., Oncogene 17 (1989) 3045-3054
Kuba, K., et al., Cancer Res. 60 (2000) 6737-6743
Miyazawa, K. et al., Biochem. Biophys. Res. Comm. 163 (1989) 967-973
Nakamura, T., et al., Biochem. Biophys. Res. Commun. 22 (1984) 1450-1459
Nakamura, T., et al., Nature 342 (1989) 440-443
Okajima, A., et al., Eur. J. Biochem. 193 (1990) 375-381
Parr, C., et al., Int. J. Cancer 85 (2000) 563-570
Seki, T., et al., Biochem. and Biophys. Res. Comm. 172 (1990) 321-327
Stahl, S. J., Biochem. J. 326 (1997) 763-772
Stuart, K. A., et al., Int. J. Exp. Pathol. 81 (2000) 17-30
Tashiro, K., et al., Proc. Natl. Acad. Sci. USA 87 (1990) 3200-3204
U.S. Pat. No. 5,977,310
Weidner, K. M., et al., Proc. Natl. Acad. Sci. USA 88 (1991) 7001-7005
WO 93/23541 | A method for the production of the N-terminal four kringle-containing fragment of hepatocyte growth factor (NK4) by expression of a nucleic acid encoding said NK4 in a microbial host cell, isolation of inclusion bodies containing said NK4 in denatured form, solubilization of the inclusion bodies and naturation of the denatured NK4, characterized in that solubilization and naturation are performed at pH 7-9 in phosphate buffered solution, provides NK4 in high purity and high yield. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a combustion power-operated setting tool including a propellant-operated setting mechanism, an ignition device for igniting the propellant, and a receptacle for a propellant holder. The present invention also relates to a propellant holder for a combustion power-operated setting tool.
2. Description of the Prior Art
Setting tools of the type described above can be operated with liquid or gaseous fuels that act as propellants and are generally stored in propellant holders.
German Publication DE-42 43 617 A1 discloses a combustion power-operated setting tool in which during an operational cycle, a gas inlet valve mechanically opens to provide for flow of fuel from a propellant holder into a storage chamber. From the storage chamber, the fuel flows into a combustion chamber before an ignition process is initiated. The propellant holder is formed as a cartridge with a liquefied gas and which is replaceably received in a receptacle of the setting tool.
The drawback of the disclosed setting tool consists in that in case of absence of the propellant holder in the receptacle, the residual fuel in the storage chamber can be still available, and an unintended actuation of a setting process by the tool user can take place, while the user believes that the setting tool is not operation-ready because of the absence of the propellant holder in the tool receptacle.
Accordingly, an object of the present invention is a setting tool of the type described above in which the foregoing drawback of the known setting tool is eliminated.
SUMMARY OF THE INVENTION
This and other objects of the present invention, which will become apparent hereinafter are achieved by providing in a setting tool a device for sensing presence of the propellant holder in the receptacle and which blocks ignition of the propellant by the ignition device in absence of the propellant holder in the receptacle and provides for the ignition of the propellant by the ignition device upon sensing the presence of the propellant holder in the receptacle.
Blocking of the ignition mechanism prevents an unintended ignition of propellant or fuel gas that still remains in the setting tool.
Advantageously, the sensing device includes switching means that opens the ignition current circuit in the absence of the propellant holder in the receptacle and closes the ignition current circuit when the presence of the propellant holder in the receptacle is detected. The switching means insures a very rapid and substantially disturbance-free blocking of the ignition mechanism or of the ignition device.
Advantageously, the sensing device includes a sensor. With a sensor, the presence or absence of a propellant holder in the tool receptacle can be determined in a simple manner, contact-free and reliably. The sensor can be formed, e.g., as a Hall sensor, capacitance sensor, or a light barrier sensor.
It is advantageous when the sensing device includes a touch contact switch which is deflected or pressed by the propellant holder when it is located in the tool receptacle. With a touch contact switch, a cost-effective construction of the sensing device can be obtained.
Advantageously, the sensor and/or the touch contact switch of the sensing device is arranged in the region of the receptacle, which makes a disturbance-free detection of the presence of a propellant holder in the tool receptacle possible.
It is further advantageous when the propellant holder such as, e.g., a fuel pressure vessel, has sensor means that can be easily recognized by the setting tool sensing device. The sensor means can be formed, e.g., as a permanent magnet, which insures a good detectability of the propellant holder when the sensing device sensor is formed as a Hall sensor.
The novel features of the present invention, which are considered as characteristic for the invention, are set forth in the appended claims. The invention itself, however, both as to its construction and its mode of operation, together with additional advantages and objects thereof, will be best understood from the following detailed description of preferred embodiments, when read with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
The drawings show:
FIG. 1 a side partially cross-sectional view of a setting tool according to the present invention with a propellant holder located in the tool receptacle;
FIG. 2 a side, partially cross-sectional view similar to that of FIG. 1 but without the propellant holder being located in the tool receptacle;
FIG. 3 a side, cross-sectional view showing the receptacle section of the setting tool shown in FIG. 1 with the propellant holder located in the receptacle;
FIG. 4 a cross-sectional view similar to that of FIG. 3 and showing the receptacle section of another embodiment of a setting tool according to the present invention with the propellant holder located in the receptacle; and
FIG. 5 a cross-sectional view similar to that of FIG. 3 and showing the receptacle section of yet another embodiment of a setting tool according to the present invention with the propellant holder located in the receptacle.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIGS. 1 through 3 show a setting tool 10 according to the present invention which is driven by a liquid or gaseous fuel that forms a propellant stored in a propellant holder 20 . The setting tool 10 has a housing 11 with a handle 16 formed thereon and which is provided with an actuation switch 17 with which a setting process can be initiated. The setting tool further has a setting mechanism 12 that includes a piston guide 14 , a drive piston 13 displaceable in the piston guide 14 which is formed as a cylinder, and a combustion chamber 38 adjoining the piston guide 14 . The propellant holder 20 is replaceably arranged in a receptacle 15 of the setting tool 10 . In the embodiment shown in FIGS. 1-3 , the propellant holder 20 is formed as a pressure vessel. A fuel conduit 29 connects the propellant holder 20 with a metering device 25 that includes, e.g.; first and second valves 26 , 28 and a chamber 27 arranged between the valves 26 , 28 . Another section of the fuel conduit connects the metering device 25 with the combustion chamber 38 . In this way, the propellant or fuel is fed from the propellant holder 20 through the fuel conduit 29 and the metering device 25 into the combustion chamber 38 of the setting tool 10 . In the combustion chamber 38 , there is provided an ignition device 18 for igniting an air-propellant mixture located in the combustion chamber 38 .
The setting tool 10 further includes a sensing device 30 having a sensor 32 , which is formed as a Hall sensor, and switching means 31 , e.g., an electronic switch. The sensor 32 is arranged on the receptacle 15 , projecting partially into the receptacle interior. The switching means 31 can form part of the sensor 32 or be formed as a separate part, as shown in FIGS. 1 and 2 . The switching means 31 forms part of an ignition current circuit 19 and closes or opens the same.
The propellant holder 20 , which is formed as pressure vessel, has a housing 21 in an interior 22 of which the propellant in form of gaseous and/or liquid fuel, e.g., a liquefied gas is stored. The propellant holder 20 , which is shown in FIGS. 1 and 3 , has, at its side adjacent to the fuel conduit 29 , sensor means 24 formed as a permanent magnet. The sensor means 24 cooperates with the sensor 32 , which is formed as a Hall sensor, of the sensing device 30 of the setting tool 10 . By sensing the presence of the sensor means 24 , the sensing device 30 ascertains presence of the propellant holder 20 in the receptacle 15 and closes, with the switching means 31 , the ignition current circuit 19 as shown in FIG. 1 , so that the ignition device 18 can be actuated by the actuation switch 17 when the setting tool 10 is pressed against a constructional component.
FIG. 2 shows the setting tool 10 without a propellant holder located in the receptacle 15 and connected with the fuel conduit 29 . However, the propellant can still be located in the conduit 29 and in the chamber 27 of the metering device in particular. However, the sensor 32 would only register the absence of the propellant holder 20 in the receptacle 15 , and the switching means 31 would open the ignition current circuit 19 . Therefore, an accidental actuation of the setting tool 10 is not possible.
The setting tool, the receptacle section of which is shown in FIG. 4 , differs from the setting tool, which was described above with reference to FIGS. 1 - 3 , in that the sensing device 30 includes, instead of a sensor and switching means, a touch contact switch 33 integrated directly into the ignition current circuit 19 . A pure mechanical presence of the propellant holder 20 is detectable by the touch contact switch 33 that opens the ignition current circuit 19 in the absence of the propellant holder 20 in the receptacle 15 . Other particularities of this embodiment of the inventive setting tool are the same as of the setting tool 10 , which were described with reference to FIGS. 1-3 .
The setting tool, the receptacle section of which is shown in FIG. 5 , differs from the setting tool shown in FIGS. 1-3 in that the sensing device 30 has, instead of a Hall sensor, a capacitance sensor 32 . The sensor 32 is connected with switching means in the same way as it was described with reference to FIGS. 1-3 . In the absence of a propellant holder 20 in the receptacle 15 , the capacitance field in front of the capacitance sensor 32 changes. The switching means of the sensing deice 30 opens the ignition current circuit, so that actuation of the setting tool is not possible. All other particularities of the setting tool shown in FIG. 5 are the same as those of the setting tool 10 , which were described with reference to FIGS. 1-3 . invention and are not to be construed as a limitation thereof, and various modifications of the present invention will be apparent to those skilled in the art. It is, therefore, not intended that the present invention be limited to the disclosed embodiments or details thereof, and the present invention includes all variations and/or alternative embodiments within the spirit and scope of the present invention as defined by the appended claims. | A combustion power-operated setting tool has a propellant-driven setting mechanism, ( 12 ) an ignition device ( 18 ) for igniting a propellant, a receptacle ( 15 ) for receiving a propellant holder ( 20 ) and a device ( 30 ) for sensing presence of the propellant holder ( 20 ) in the receptacle ( 15 ) and which blocks ignition of the propellant by the ignition device in absence of the propellant holder in the receptacle ( 15 ) and provides for the ignition of the propellant by the ignition device upon sensing the presence of the propellant holder ( 20 ) in the receptacle ( 15 ). | 1 |
TECHNICAL FIELD
The technical field is gas chromatography, and in particular, retention time locking and multidimensional gas chromatography.
BACKGROUND ART
Prior Art of Multidimensional Gas Chromatography
Multidimensional chromatography is technique that employs more than one separation stage (phase). Multidimensional gas chromatography is typically performed by coupling more than one gas chromatography column in series. The different columns usually have different stationary phases. The different stationary phases employ different separation mechanisms resulting in increased separation between the components of the sample. The columns are selected so that the components of interest in the sample will be separated in either one or the other or in combination of the two columns.
In standard multidimensional gas chromatography, the entire sample is introduced into the first column. The sample flows through the first column where the initial separation takes place. The sample is then transferred directly into the second column. The transferred sample then flows through the second column where the second separation takes place. Finally, the sample then flows from the second column directly into the detector.
There are several variations of the standard technique. Most commonly, only a portion of the sample is transferred from the first column into the second column. This technique, known as “heart cutting,” is used to effect separations in especially complex mixtures. The portion transferred to the second column generally contains a much less complex subset mixture than the original sample. A less common variation of the standard method, known as splitting, directs a fraction of the sample exiting the first column into a detector and directs the remaining fraction into the second column. The main advantage of heart cutting is it allows the chromatographer to monitor the separation on the first column as well as the second column.
Comprehensive multidimensional gas chromatography (CMDGC) is another variation of the standard technique. CMDGC employs an additional step during the transfer of the sample between columns. The additional step periodically focuses and desorbs the sample at a transition stage between columns. The focusing-desorption of the sample is accomplished by thermal modulation of the sample at the transfer point between the columns. The sample is accumulated and “focused” at a point prior to the entrance of the second column. Focusing is usually accomplished by a cooling device that retains the sample. The focused sample is then heated in the desorption step, which accelerates a portion of the retained sample into the second column. The accelerated portion of the sample or “desorption” is performed at timed intervals. The focusing-desorption step has the effect of releasing concentrated pulses of sample into the carrier stream, thereby increasing separation and detectability in the second column.
The focusing-desorption step is computer controlled. The computer records the focus time and the desorption time. The focus time corresponds to the elution time for an analyte from the first column. The desorption time corresponds to the injection time of the analyte into the second column. Elution time and injection time allows the chromatographer to determine the elution time of the solutes from the first column as well as the elution time of the second column.
The typical output from a CMDGC is a three dimensional (3D) plot with axes corresponding to retention time on the first and second column (usually x and y-axes), and the detector response representing the z-axis. Alternately, the 3D plot may be collapsed into “iso” plots that represent a top-down (x and y-axes) view of the standard 3D plot.
With all types of multidimensional gas chromatography (GC), additional dimensions are possible with the addition of more columns or with detectors that provide multidimensional signals. Examples of multidimensional signal detectors include mass spectrometers, absorbance spectrometers, and emission spectrometers.
A disadvantage of standard and comprehensive multidimensional GC is that the retention times (the time it takes analytes to elute from a column) for single or multiple compounds can vary from instrument to instrument and even day to day on the same instrument. The variations, which can occur in each column of a multidimensional system, may be due to instrument drift, atmospheric changes, oven design, column dimension differences such as length or diameter, and stationary phase degradation.
The inconsistency of retention times increases the complexity of the resulting data. Inconsistency of retention times also disrupts the timing for heartcutting, thereby leading to inaccurate results. The data reduction and interpretation time resulting from these variations is increased significantly. The chromatographer must compensate for the variations or reanalyze the samples prior to interpreting the results each time a variation occurs. In effect, every data set containing a retention time variation must be evaluated as if it were a new method.
Prior Art of Retention-Time Locking
Retention-time locking is a technique that adjusts operational parameters of a gas chromatograph to avoid variations in retention time. Retention-time locking compensates for system, time-to-time, and location-to-location matching of retention times between known or reference systems and new or different systems.
Retention-time locking is accomplished through various methods. The only requirement of retention-time locking is that the columns used have the same stationary phase type (chemistry) and the same nominal phase ratio. Most commonly, the column head pressure on the new or different system is adjusted so that the column void time or the retention time of a known analyte equals a defined value (the defined value being ascertained on a reference system). Head pressure is most commonly regulated by a precise pressure controller. The adjusted head pressure compensates for differences in column and operational parameters producing retention times identical or nearly identical to those of the reference system.
Some varieties of pressure controllers can also react and adjust to changes in operating conditions including, for example, changes in ambient (atmospheric) pressure and temperature fluctuations. The added control can help to fine tune head pressure and provide even better retention time stability.
Retention time locking can be utilized in combination with other chromatographic techniques such as, for example, method translation and retention time factors. Method translation is a process that allows one to predictably scale a known set of chromatographic conditions in response to a desired change in one or more system parameters. Functions that relate gas flow rate in the column to column dimensions (length and diameter), temperature, carrier gas type, stationary phase film thickness, inlet pressure, and outlet pressure are used to calculate appropriate new sets of conditions. Using method translation, peak elution order and relative retention are maintained, and retention times of analytes are precisely predicted. Because there is usually some uncertainty in the exact column dimensions, oven temperature, and stationary film thickness, method translation can be followed by retention time locking to better match new retention times to a predicted retention time on a reference system.
Retention factors represent normalized retention times. Considering that GC methods can be scaled, reduced representations of retention time resulting from locked but scaled methods can be more easily compared or used. For example, results from a reference GC can be searched against the same library of retention factors for a scaled GC system that is running at fives times the speed of the reference system. If retention factors were not used, either the chromatographic data from the faster system would have to be multiplied by 5, or the data in the library would have to be divided by 5 prior to searching. The concept of using retention factors with retention time locked GC systems is highlighted in U.S. Pat. No. 6,153,438.
SUMMARY
A method applies retention-time locking to multidimensional gas chromatography. Retention time locking is applied to both standard and comprehensive multidimensional gas chromatography. The method simplifies data interpretation compared to conventional methods. The consistency of retention times generated by the method allows users to reduce time spent correlating data generated over time and between instruments. The consistency of retention times also allows the creation of a general compound library or map that can be used for compound identification, compound class identification and determining the chemical nature and properties of sample components on any similar multidimensional GC system operated under locked conditions.
In an embodiment, retention time locking may be applied to either or both of the columns in a multidimensional gas chromatography system. Additionally, if the multidimensional system contains more than two columns in series, retention time locking can be applied to any or all of the columns as required.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 diagrams a basic multidimensional GC configured for retention time locking.
FIG. 2 diagrams a multidimensional GC with additional columns configured for retention time locking.
FIG. 3 diagrams a comprehensive multidimensional GC configured for retention time locking.
FIG. 4 depicts an iso plot for multidimensional GC.
DETAILED DESCRIPTION
A method for retention time locking a multidimensional GC is described. The method applies to a multidimensional GC system containing more than one column as well as to comprehensive multidimensional GC systems with one or more focusing and desorption sites. A method for generating a general compound map that is consistent between multidimensional system is also disclosed.
FIG. 1 diagrams a basic multidimensional GC system 1 configured for retention time locking. The basic multidimensional GC system 1 includes two columns 20 a and 20 b connected in series. Columns 20 a and 20 b have inlets 21 a and 21 b and outlets 22 a and 22 b respectively, with corresponding outlet pressures and inlet pressures (also known as head pressure). A sample introduction source 10 is positioned at the inlet 21 a of the first column 20 a . The preferred sample introduction source 10 is a chromatographic inlet, however other sample introduction sources may be used including, for example, valves, thermal desorbers, pyrolyzers, headspace, and solid phase micro extraction. A precise pressure controller 15 a is also positioned at the inlet 21 a of the first column 20 a . A precise pressure controller controls the head pressure of the column it to which it is connected. In FIG. 1 the precise pressure controller 15 a controls the head pressure of the first column 20 a . The preferred precise pressure controller is an Electronic Pneumatic Control (EPC), however, others controllers may be used including, for example, traditional single or multiple stage pressure controllers. The outlet 22 a of the first column 20 a and the inlet 21 b of the second column 20 b are connected at a junction 25 a . A second precise pressure controller 15 b is positioned at the junction 25 a between the first column 20 a and the second column 20 b . Again, the preferred precise pressure controller 15 b is an EPC. The second precise pressure controller 15 b controls the head pressure of the second column 20 b . A detector 30 is positioned at the outlet 22 b of the second column 20 b . The detector 30 can be any detector used in the art. The choice of detector 30 will depend on the specific requirements of the chromatographic method employed. No single detector 30 is preferred because different detectors 30 are more suitable for different analyses. If desired, the detector 30 can be replaced by another useful device, such as a fraction collector for example, or removed altogether.
In operation, carrier gas flows, with or without solutes from the sample introduction source 10 , from the inlet 21 a of the first column 20 a through the first column 20 a , and is joined at the junction 25 , with flow from the second precise pressure controller 15 b . Thereafter, the combined flow continues through the second column 20 b to the detector 30 . Samples reach the detector 30 after traveling through both columns 20 a and 20 b
The preferred method of retention time locking the multidimensional chromatography system 1 is to lock the overall retention time; the overall retention time is the sum of the individual retention times for the first column 20 a and the second column 20 b . Locking the overall retention time is accomplished by retention time locking both columns 20 a and 20 b . The preferred way to lock the overall retention time is to lock the second column 20 b first and the first column 20 a second. Locking the overall retention time in this order is most straightforward because the head pressure of the second column 20 b is the outlet pressure of the first column 20 a.
Locking the overall retention time on the two column multidimensional GC system 1 is accomplished by performing the following steps: (1) configuring operating parameters of a reference multidimensional GC system in accordance with a known chromatographic method, wherein the reference multidimensional GC system includes a first column and a second column connected in series, each of the columns having a known stationary phase, nominal diameter and length, and phase ratio; (2) injecting one or more known analytes into the reference multidimensional GC system yielding defined analyte retention times and/or defined void times for each column; (3) configuring operating parameters of a locking mulitidmensional GC system in accordance with the known chromatographic method, wherein the locking multidimensional GC includes a first column and a second column, each of the columns having a same known stationary phase, nominal diameter and length and phase ratio as the reference multidimensional GC system and wherein the first column and second column have a head pressure; (4) adjusting the head pressure of the second column such that the retention times of the known analytes and/or void time for the second column are matched to the corresponding defined analyte retention times and/or defined void time; and (5) adjusting the head pressure of the first column such that the retention times of the known analytes and/or void time for the second column are matched to the corresponding defined analyte retention times and/or defined void time.
Several methods for calculating and/or determining the appropriate adjustments to the head pressure are known in the art such as, for example, the empirical approach or standard mathematical relationships for void time calculations. Any known method can be used, however the preferred method is described in U.S. Pat. No. 5,987,959 and is incorporated herein by reference as if fully set forth. These methods require the retention times of analytes on individual columns be able to be determined.
The retention time of analytes or void time on the second column 20 b may be determined directly by introducing one or more known analytes or a non-retained component at the junction 25 between the columns 20 a and 20 b . This can be accomplished by using a sample introduction source 10 as the source of the pressure 15 b between the first column 20 a and the second column 20 b.
Once locked, the retention time of analytes or void time on the first column 20 a may be determined indirectly by introducing one or more known analytes or a non-retained component into the sample introduction source 10 yielding a total retention time for both columns. The retention time for the analyte in the first column 20 a is calculated by subtracting the retention time of the second column 20 b (which is known because the second column 20 b is locked) from the total retention time.
Although retention time locking the entire system is the preferred method, either the first column 20 a or the second column 20 b may be individually retention time locked without locking the remaining column. Retention time locking and individual column in a multidimensional GC system is accomplished by controlling the precise head pressure controller connected to the individual column to be locked.
The method used to retention time lock the basic multidimensional GC system 1 described in FIG. 1 may be applied to any variation of the basic system 1 . FIGS. 2 and 3, for example, show other embodiments of the basic system to which the method of this invention can be applied. In general, the discussion of the components in FIG. 1 applies to the components in FIGS. 2 and 3 unless otherwise noted. Columns 20 a and 20 b have inlets 21 a and 21 b and outlet 22 a and 22 b , respectively, with corresponding outlet pressures and inlet pressures. A sample introduction source 10 is positioned at the inlet 21 a of the first column 20 a . A precise pressure controller 15 a is also positioned at the inlet 21 a of the first column 20 a and a second precise pressure controller 15 b is positioned at the junction 25 a between the first column 20 a and the second column 20 b.
The system 2 of FIG. 2 deviates from the basic system at the outlet 22 b of the second column 20 b . The outlet 22 b of the second column 20 b is connected to an inlet 21 c of a third column 20 c at a second junction 25 b . A third precise pressure controller 15 c is positioned at the second junction 25 b . The third precise pressure controller 15 c controls the head pressure of the third column 20 c . The outlet 22 c of the third column 20 c is connected to an inlet 21 d of a fourth column 20 d at a third juncture 25 c . A fourth precise pressure controller 15 d is positioned at the third juncture 25 c . The fourth precise pressure controller 15 d controls the head pressure of the fourth column 20 d . An outlet 22 d of the fourth column 20 d is connected to a detector 30 .
The use of four columns connected in series in FIG. 2 is illustrative. Retention time locking can be applied to any multidimensional GC systems with more than one column. Each column to be retention time locked in a multidimensional GC system may use a precise pressure controller to control the head pressure of that column. As with the basic multidimensional GC system 1 , the preferred method of retention time locking a multidimensional GC system with 3 or more columns is to lock the overall retention time for the entire system. Locking the overall retention time requires that each column of a system be retention time locked. The preferred method for locking a multidimensional GC system with 3 or more columns is to lock the columns sequentially, starting with the last column and proceeding to the first column. Using FIG. 2 as an example, in order to lock the overall retention time, the fourth column 20 d is locked first, the third column 20 c is locked with 3 or more columns is to lock the columns sequentially, starting with the last column and proceeding to the first column. Using FIG. 2 as an example, in order to lock the overall retention time, the fourth column 20 d is locked first, the third column 20 c is locked second, the second column 20 b is locked third, and the first column 20 a is locked last. Once all the columns are locked, the overall retention time is locked.
As with the basic multidimensional GC system 1 , any individual column or combination of columns can be retention time locked in a multidimensional GC system with 3 or more columns. This is accomplished by controlling the precise pressure controller connected to the column or combination of columns to be locked.
Locking the retention time of one or more columns on a multidimensional GC system is accomplished by performing the following steps: (1) configuring operating parameters of a reference multidimensional GC system in accordance with a known chromatographic method, wherein the reference multidimensional GC includes more than one column connected in series, each of the columns having a known stationary phase, nominal diameter and length, and phase ratio; (2) introducing one or more target analytes into the reference multidimensional GC system yielding defined analyte retention times and/or defined void times for one or more columns of the reference multidimensional GC; (3) configuring operating parameters of a locking multidimensional GC system in accordance with the known chromatographic method, wherein the locking multidimensional GC system includes a same number of columns connected in series as the reference multidimensional GC system, each of the same number of columns having a same known stationary phase, nominal diameter and length and phase ratio as the reference multidimensional GC system and wherein each column of the locking multidimensional GC system has a head pressure; (4) locking the retention times of the target analytes or void times on one or more columns of the locking multidimensional GC system, beginning with a last column in series to be locked and proceeding sequentially to a first column to be locked, by adjusting the head pressure of the column to be locked such that the retention times of the target analytes or column void times on the locking multidimensional GC system are matched to the corresponding defined analyte retention times and/or defined column void times.
FIG. 3 depicts a comprehensive multidimensional GC system 3 configured for retention time locking. The comprehesnsive multidimensional GC system 3 is set up similar to the basic multidimensional GC system 1 except a focus-desorption device is positioned at the junction 25 a between the first column 20 a and the second column 20 b . The focus-desorption device does not replace the precise pressure controller 15 b , but is connected at the junction 25 a in addition to the precise pressure controller 15 b . Traditional (non-retention time locked) comprehensive multidimensional gas chromatography does not use a pressure controller between the first and second columns; however the second precise pressure controller is necessary in the system 3 of FIG. 3 to retention time lock the second column.
As with other multidimensional GC systems, the preferred method for retention time locking the comprehensive multidimensional GC system 3 is to lock the overall retention time. This is accomplished by locking both columns 20 a and 20 b in the system 3 . The preferred method of locking the overall retention time of the system 3 is to lock the second column 20 b first and lock the first column 20 a second.
The retention time of analytes or void time on the second column on a comprehensive multidimensional GC can be computed directly. The focusing-desorption device is computer controlled. The time of desorption of an analyte at the junction between columns is the injection time for that analyte into the second column 20 b , so the retention time of that analyte for the second column 20 b can be computed directly. Similarly, the retention time or void time on the first column 20 a may also be computed directly because the time of focusing for an analyte represents the retention time of that analyte for the first column 20 a.
Although retention time locking the entire multidimensional GC system 3 is the preferred method, either the first column 20 a or the second column 20 b may be individually retention time locked without locking the remaining column. This is accomplished by controlling the precise pressure controller connected to the individual column to be locked.
The system 3 of FIG. 3 illustrates how retention time locking can be used on a comprehensive multidimensional GC system. Other comprehensive multidimensional GC systems can be configured for retention time locking. For example, additional columns, such as in FIG. 2 can be included in a comprehensive multidimensional GC system. Alternatively, a focus-desorption device can be placed at any junction between columns or at the inlet 21 a at the first column or at the outlet of the last column in series before the detector 30 .
Retention time locking of any of the abovementioned multidimensional GC systems can be implemented in combination with other known chromatography techniques such as scaling of conditions or a retention factor approach. Throughout this application, any reference to multidimensional GC includes comprehensive multidimensional GC unless otherwise noted.
Retention time locked multidimensional GC conditions can be scaled exactly. When scaling the conditions of a locked multidimensional GC method, the method is first translated using the technique of “method translation,” followed by retention time locking the scaled method. The technique of method translation is described in “PreciseTime-Scaling of Gas Chromatographic Methods Using Method Translation and Retention Time Locking Application”, B. D. Quimby, L. M. Blumberg, M. S. Klee, and P. L. Wylie, Agilent Technologies Application Note 5967-5820E, 3/2000 and U.S. Pat. No. 5,405,432, both of which are incorporated herein by reference as if fully set forth. The scaling of conditions of a retention time locked multidimensional GC enables the user to respond to changing requirements of an analysis.
For example, if the user requires a decreased analysis time, a shorter column or a column with a smaller internal diameter can replace the column called for by the method. The replacement column may produce a shorter analysis time with known speed gain for all analytes. The resulting scaled method can then be retention time locked producing an exactly scaled method. Any or all of the individual columns of a locked multidimensional GC system can be scaled depending on the user's requirements. For example, the analysis time of the initial separation in the first column can be changed while maintaining the separation speed of the second column, or alternatively, the separation speed of the second column can be changed while maintaining the separation speed of the first.
The results or data produced by various scaled conditions of a common retention time locked multidimensional GC system can easily be compared against the original conditions or against differently scaled conditions by implementing a retention time factor approach. The retention time factor approach converts retention times of an analysis to retention factors. Retention factors are retention times normalized to void time or locked reference time. The method for converting retention times into retention factors is described in U.S. Pat. No. 6,153,438 and is incorporated herein by reference as if fully set forth. The time normalization that results from the conversion of retention times reduces retention times to a common scale.
A retention time or retention factor locked multidimensional GC system may be used for creating a general compound map that is consistent between locked multidimensional GC systems.
FIG. 4 depicts an iso plot for multidimensional GC configured with two columns. In FIG. 4 multidimensional chromatographic space is represented by axes. The x-axis represents the retention time for analytes eluting from the first column. The y-axis represents the retention time for analytes eluting from the second column. The circles within the chart represent specific compounds that have been separated through the combined set of both the first and second column. Typically, concentric circles are used to indicate signal intensity, however other methods are used such as color, for example. The lines illustrate typical patterns that result for the elution of homologs.
General compound maps can be created for multidimensional GC systems operated under locked conditions. The general compound map may be used to identify compounds on any multidimensional GC system operated under the same locked conditions as the reference multidimensional GC system used to create the general compound map. Additionally, general compound maps may be used with scaled and locked systems and with corresponding retention factor normalization. Alternatively, a retention time database of the defined analytes retention times may be created. The data points in multidimensional chromatographic space may be stored in a database.
The method for creating a compound map comprises injecting a series of known analytes into a reference system under locked conditions and generating a retention time database. The reference system must have the overall retention time locked. Each analyte injected will produce corresponding retention time data for each column in the reference system. For example, if the reference system has two columns (a and b) connected in series, each known analyte injected will have a corresponding retention time for column a and a corresponding retention time for column b. The values obtained are placed in a database and form the basis for identification of unknowns eluting at specific times from columns a and
FIG. 4 depicts an iso plot for multidimensional GC configured with two columns. In FIG. 4 multidimensional chromatographic space is represented by axes. The x-axis represents the retention time for analytes eluting from the first column. The y-axis represents the retention time for analytes eluting from the second column. The circles within the chart represent specific compounds that have been separated through the combined set of both the first and second column. Typically, concentric circles are used to indicate signal intensity, however other methods are used such as color, for example. The lines illustrate typical patterns that result for the elution of homologs.
General compound maps can be created for multidimensional GC systems operated under locked conditions. The general compound map may be used to identify compounds on any multidimensional GC system operated under the same locked conditions as the reference multidimensional GC system used to create the general compound map. Additionally, general compound maps may be used with scaled and locked systems and with corresponding retention factor normalization. Alternatively, a retention time database of the defined analytes retention times may be created. The data points in multidimensional chromatographic space may be stored in a database.
The method for creating a compound map comprises injecting a series of known analytes into a reference system under locked conditions and generating a retention time database. The reference system must have the overall retention time locked. Each analyte injected will produce corresponding retention time data for each column in the reference system. For example, if the reference system has two columns (a and b) connected in series, each known analyte injected will have a corresponding retention time for column a and a corresponding retention time for column b. The values obtained are placed in a database and form the basis for identification of unknowns eluting at specific times from columns a and b.
The reference system must also be configured so that the retention times of the analytes can be monitored after they elute from each individual column in the system. Techniques for accomplishing this are known in the art and any appropriate technique may be used. If the reference system is a comprehensive multidimensional GC, the focus-desorption step performs the function of indicating elution time from a column.
The two (or more if the reference system has more than two columns) retention times associated with each analyte can be plotted, such as on an iso-plot as shown in FIG. 4 . Each analyte has a “position” on the iso-plot. Unless two different analytes have identical retention times for both columns, then each analyte has a unique position on the iso-plot. The retention time database and/or the iso-plot for a given reference column is a compound map that is consistent over time and between instruments and practitioners.
Any of the above described multidimensional GC systems can be equipped with a selective detector. Most selective detectors can be “tuned” to respond to specific attributes of eluting compounds. For example, a mass spectrometer detector can be tuned to detect ions with a specific mass/charge ratio or a photo diode array detector can be tuned detect compounds that emit a specific wavelength. By locking the multidimensional GC system, the user can more accurately program the selective detector to detect certain attribute at the precise time the target analyte is eluting. | A method applies retention-time locking to the retention times and/or the column(s) void times of a target analyte(s) being eluted thru a multidimensional gas chromatography system. Retention time locking is applied to both standard and comprehensive multidimensional gas chromatography via the steps of adjusting column(s) head pressure in a locking multidimensional gas chromatograph system such that the measured retention times and/or void times match the known accepted. Retention time locking may be applied to either or both of the columns in a multidimensional gas chromatography system. Additionally, if the multidimensional system contains more than two columns in series, retention time locking can be applied to any or all of the columns as required. | 6 |
FIELD OF THE INVENTION
This invention relates to aqueous inks which utilize pigments as colorants and which are useful for ink jet printing applications. Specifically, this invention relates to additives to pigmented inks which improve the resistance of solid area patches printed on coated papers and films to being removed by water (waterfastness).
BACKGROUND OF THE INVENTION
Ink jet printing is a non-impact method for producing images by the deposition of ink droplets on a substrate (paper, transparent film, fabric, etc.) in response to digital signals. Ink jet printers have found broad applications across markets ranging from industrial labeling to short run printing to desktop document and pictorial imaging. The inks used in ink jet printers are generally classified as either dye-based or pigment-based.
A dye is a colorant which is molecularly dispersed or solvated by the carrier medium. The carrier medium can be a liquid or a solid at room temperature. A commonly used carrier medium is water or a mixture of water and organic cosolvents. Each individual dye molecule is surrounded by molecules of the carrier medium. In dye-based inks, no particles are observable under the microscope. Although there have been many recent advances in the art of dye-based ink jet inks, such inks still suffer from deficiencies such as low optical densities on plain paper and poor lightfastness. When water is used as the carrier medium, such inks also generally suffer from poor waterfastness.
Pigment based inks have been gaining in popularity as a means of addressing these limitations. In pigment-based inks, the colorant exists as discrete particles. Pigment-based inks suffer from a different set of deficiencies than dye-based inks. One deficiency is related to the observation that pigment-based inks interact differently with specially coated papers and films, such as the transparent films used for overhead projection and the glossy papers and opaque white films used for high quality graphics and pictorial output. In particular, it has been observed that pigment-based inks produce imaged areas that are entirely on the surface of coated papers and films. Another defect known as "starvation" relates to some inconsistencies of the stream of ink being fired causing changes of image densities and/or loss of information. Starvation is exhibited on plain paper as well as coated papers and films.
U.S. Pat. No. 5,324,349 discloses pigmented inks for ink jet printing comprising monosaccharides, disaccharides, oligosaccharides including trisaccharides and tetrasaccharides, and polysaccharides (e.g., alginic acid, alpha cyclodextin and cellulose). These additives have a very low molecular weight, below about 1000 and are all water soluble. They are used to prevent plugging of ink jet nozzles. Such additives will not improve image quality or fastness of ink jet printed images.
What is needed, then, is an additive which will improve the resistance of said area patches to being removed by water when printed on resin or plastic coated papers and films, e.g., photographic paper and film supports coated with an ink receptive layer.
SUMMARY OF THE INVENTION
We have unexpectedly found that the addition of certain additives to the pigment-based inks greatly minimizes or eliminates the above mentioned problems.
The present invention relates to pigmented ink jet inks which comprise an aqueous carrier medium, a pigment, and at least one compound containing an aldehyde functional group such as formaldehyde, gluteraldehyde, 2,3-dihydroxy- 1,4-dioxane and the like.
When inks of the present invention are printed onto glossy coated papers and films containing an imaging layer consisting primarily of gelatin, they result in uniform, crack-free text and solid area fills of high optical density and are highly waterfast.
DETAILED DESCRIPTION OF THE INVENTION
Inks useful for ink jet recording processes generally comprise at least a mixture of a solvent and a colorant. The preferred solvent is de-ionized water, and the colorant is either a pigment or a dye. Pigments are often preferred over dyes because they generally offer improved waterfastness and lightfastness on plain paper.
The process of preparing inks from pigments commonly involves two steps: (a) a dispersing or milling step to break up the pigment to the primary particle, and (b) dilution step in which the dispersed pigment concentrate is diluted with a carrier and other addenda to a working strength ink. In the milling step, the pigment is usually suspended in a carrier (typically the same carrier as that in the finished ink) along with rigid, inert milling media. Mechanical energy is supplied to this pigment dispersion, and the collisions between the milling media and the pigment cause the pigment to deaggregate into its primary particles. A dispersant or stabilizer, or both, is commonly added to the pigment dispersion to facilitate the deaggregation of the raw pigment, to maintain colloidal particle stability, and to retard particle reagglomeration and settling.
There are many different types of materials which may be used as milling media, such as glasses, ceramics, metals, and plastics. In a preferred embodiment, the grinding media can comprise particles, preferably substantially spherical in shape, e.g., beads, consisting essentially of a polymeric resin.
In general, polymeric resins suitable for use as milling media are chemically and physically inert, substantially free of metals, solvent and monomers, and of sufficient hardness and friability to enable them to avoid being chipped or crushed during milling. Suitable polymeric resins include crosslinked polystyrenes, such as polystyrene crosslinked with divinylbenzene, styrene copolymers, polyacrylates such as poly(methyl methylacrylate), polycarbonates, polyacetals, such as Derlin™, vinyl chloride polymers and copolymers, polyurethanes, polyamides, poly(tetrafluoroethylenes), e.g., Teflon™, and other fluoropolymers, high density polyethylenes, polypropylenes, cellulose ethers and esters such as cellulose acetate, poly(hydroxyethylmethacrylate), poly(hydroxyethyl acrylate), silicone containing polymers such as polysiloxanes and the like. The polymer can be biodegradable. Exemplary biodegradable polymers include poly(lactides), poly(glycolids) copolymers of lactides and glycolide, polyanhydrides, poly(imino carbonates), poly(N-acylhydroxyproline) esters, poly(N-palmitoyl hydroxyprolino) esters, ethylene-vinyl acetate copolymers, poly(orthoesters), poly(caprolactones), and poly(phosphazenes). The polymeric resin can have a density from 0.9 to 3.0 g/cm 3 . Higher density resins are preferred inasmuch as it is believed that these provide more efficient particle size reduction. Most preferred are crosslinked or uncrosslinked polymeric media based on styrene.
Milling can take place in any suitable grinding mill. Suitable mills include an airjet mill, a roller mill, a ball mill, an attritor mill and a bead mill. A high speed mill is preferred. The high speed mill is a high agitation device, such as those manufactured by Morehouse-Cowles, Hockmeyer et al.
By high speed mill we mean milling devices capable of accelerating milling media to velocities greater than about 5 meters per second. The mill can contain a rotating shaft with one or more impellers. In such a mill the velocity imparted to the media is approximately equal to the peripheral velocity of the impeller, which is the product of the impeller revolutions per minute, π, and the impeller diameter. Sufficient milling media velocity is achieved, for example, in Cowles-type saw tooth impeller having a diameter of 40 mm when operated at 7,000 rpm. The preferred proportions of the milling media, the pigment, the liquid dispersion medium and dispersant can vary within wide limits and depends, for example, upon the particular material selected and the size and density of the milling media etc. The process can be carried out in a continuous or batch mode.
Batch Milling
A slurry of <100 μm milling media, liquid, pigment and dispersant is prepared using simple mixing. This slurry may be milled in conventional high energy batch milling processes such as high speed attritor mills, vibratory mills, ball mills, etc. This slurry is milled for a predetermined length of time to allow comminution of the active material to a minimum particle size. After milling is complete, the dispersion of active material is separated from the grinding media by a simple sieving or filtration.
Continuous Media Recirculation Milling
A slurry of <100 μm milling media, liquid, pigment and dispersant may be continuously recirculated from a holding vessel through a conventional media mill which has a media separator screen adjusted to >100 μm to allow free passage of the media throughout the circuit. After milling is complete, the dispersion of active material is separated from the grinding media by simple sieving or filtration.
With either of the above modes the preferred amounts and ratios of the ingredients of the mill grind will vary widely depending upon the specific materials and the intended applications. The contents of the milling mixture comprise the mill grind and the milling media. The mill grind comprises pigment, dispersant and a liquid carrier such as water.
For aqueous ink jet inks, the pigment is usually present in the mill grind at 1 to 50 weight %, excluding the milling media. The weight ratio of pigment to dispersant is 20:1 to 1:2.
The liquid carrier medium can also vary widely and, again, will depend on the nature of the ink jet printer for which the inks are intended. For printers which use aqueous inks, water, or a mixture of water with miscible organic co-solvents, is the preferred carrier medium.
Selection of a suitable mixture depends on requirements of the specific application, such as desired surface tension and viscosity, the selected pigment, drying time of the pigmented ink jet ink, and the type of paper onto which the ink will be printed. Representative examples of water-soluble co-solvents that may be selected include (1) alcohols, such as methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, sec-butyl alcohol, t-butyl alcohol, iso-butyl alcohol, furfuryl alcohol, and tetrahydrofurfuryl alcohol; (2) ketones or ketoalcohols such as acetone, methyl ethyl ketone and diacetone alcohol; (3) ethers, such as tetrahydrofuran and dioxane; (4) esters, such as ethyl acetate, ethyl lactate, ethylene carbonate and propylene carbonate; (5) polyhydric alcohols, such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, tetraethylene glycol, polyethylene glycol, glycerol, 2-methyl-2,4-pentanediol 1,2,6-hexanetriol and thioglycol; (6) lower alkyl mono- or di-ethers derived from alkylene glycols, such as ethylene glycol mono-methyl (or -ethyl) ether, diethylene glycol mono-methyl (or -ethyl) ether, propylene glycol mono-methyl (or -ethyl) ether, triethylene glycol mono-methyl (or -ethyl) ether and diethylene glycol di-methyl (or -ethyl) ether; (7) nitrogen containing cyclic compounds, such as pyrrolidone, N-methyl-2-pyrrolidone, and 1,3-dimethyl-2-imidazolidinone; and (8) sulfur-containing compounds such as dimethyl sulfoxide and tetramethylene sulfone.
The dispersant is another important ingredient in the mill grind. Although there are many dispersants known in the art, the best dispersant will be a function of the carrier medium and will also often vary from pigment to pigment. Preferred dispersants for aqueous ink jet inks include sodium dodecyl sulfate, acrylic and styrene-acrylic copolymers, such as those disclosed in U.S. Pat. Nos. 5,085,698 and 5,172,133, and styrenics, such as those disclosed in U.S. Pat. No. 4,597,794. For the present invention, the most preferred dispersant is oleoyl methyl taurine, sodium salt (OMT), obtained from Synthetic Chemical Div. of Eastman Kodak Co.
The milling time can vary widely and depends upon the pigment, mechanical means and residence conditions selected, the initial and desired final particle size, etc. For aqueous mill grinds using the preferred pigments, dispersants, and milling media described above, milling times will typically range from 1 to 100 hours. The milled pigment concentrate is preferably separated from the milling media by filtration.
In the present invention, any of the known pigments can be used. Pigments can be selected from those disclosed, for example, in U.S. Pat. No. 5,085,698, Cols. 7 and 8. The exact choice of pigment will depend upon the specific color reproduction and image stability requirements of the printer and application. For four-color printers, combinations of cyan, magenta, yellow, and black (CMYK) pigments should be used. An exemplary four color set may be a bridged aluminum phthalacyanine pigment, copper phthalocyanine (pigment blue 15), quinacridone magenta (pigment red 122), pigment yellow 138 and carbon black (pigment black 7).
Ink Preparation
In general it is desirable to make the pigmented ink jet ink in the form of a concentrated mill grind, which is subsequently diluted to the appropriate concentration for use in the ink jet printing system. This technique permits preparation of a greater quantity of pigmented ink from the equipment. If the mill grind was made in a solvent, it is diluted with water and optionally other solvents to the appropriate concentration. If it was made in water, it is diluted with either additional water or water miscible solvents to make a mill grind of the desired concentration. By dilution, the ink is adjusted to the desired viscosity, color, hue, saturation density, and print area coverage for the particular application.
In the case of organic pigments, the ink may contain up to approximately 30% pigment by weight, but will generally be in the range of approximately 0.5 to 10%, preferably approximately 0.1 to 5%, by weight of the total ink composition for most thermal ink jet printing applications. If an inorganic pigment is selected, the ink will tend to contain higher weight percentages of pigment than with comparable inks employing organic pigments, and may be as high as approximately 75% in come cases, since inorganic pigments generally have higher specific gravities than organic pigments.
The amount of aqueous carrier medium is in the range of approximately 70 to 98 weight %, preferably approximately 90 to 98 weight %, based on the total weight of the ink. A mixture of water and a polyhydric alcohol, such as diethylene glycol, is preferred as the aqueous carrier medium. In the case of a mixture of water and diethylene glycol, the aqueous carrier medium usually contains from about 30% water/70% diethylene glycol to about 95% water/5% diethylene glycol. The preferred ratios are approximately 60% water/40% diethylene glycol to about 95% water/5% diethylene glycol. Percentages are based on the total weight of the aqueous carrier medium.
In the dilution step, other ingredients are also commonly added to pigmented ink jet inks. Cosolvents (0-20 wt %) are added to help prevent the ink from drying out or crusting in the orifices of the printhead or to help the ink penetrate the receiving substrate, especially when the substrate is a highly sized paper. Preferred cosolvents for the inks of the present invention are glycerol, ethylene glycol, and diethylene glycol, and mixtures thereof, at overall concentrations ranging from 5 to 25 wt %.
In the context of the present invention, an especially important additive is a compound containing an aldehyde functionality such as formaldehyde, glutaraldehyde, 2,3-dihydroxy-1,4-dioxane (DHD) and the like.
It is contemplated that aldehyde containing compounds, or precursors to aldehyde containing compounds, that are effective hardening agents for gelatin coatings are also useful in the practice of this invention. Some compounds known to be effective hardening agents are 3-hydroxybutyraldehyde (U.S. Pat. No. 2,059,817), crotonaldehyde, the homologous series of dialdehydes ranging from glyoxal to adipaldehyde, diglycolaldehyde (U.S. Pat. No. 3,304,179) and various aromatic dialdehydes (U.S. Pat. No. 3,565,632 and U.S. Pat. No. 3,762,926). Additional related hardening agents can be found in Research Disclosure, Vol. 365, September 1994, Item 36544, II, B. Hardeners.
It has been unexpectedly found that improved image quality, excellent optical density, and improved waterfastness on gelatin coated papers and films can be achieved when specific compounds containing aldehyde functionality are added to the ink compositions. Most preferred is DHD at concentrations ranging from about 0.20 to 3.0 wt % based on the total weight of the ink.
A biocide (0.01-1.0 wt %) may be added to prevent unwanted microbial growth which may occur in the ink over time. A preferred biocide for the inks of the present invention is Proxel GXL (obtained from Zeneca Colours) at a final concentration of 0.05-0.5 wt %.
Jet velocity, separation length of the droplets, drop size and stream stability are greatly affected by the surface tension and the viscosity of the ink. Pigmented ink jet inks suitable for use with ink jet printing systems should have a surface tension in the range of about 20 dynes/cm to about 60 dynes/cm and, more preferably, in the range 30 dynes/cm to about 50 dynes/cm. Control of surface tensions in aqueous inks is accomplished by additions of small amounts of surfactants. The level of surfactants to be used can be determined through simple trial and error experiments. Anionic and cationic surfactants may be selected from those disclosed in U.S. Pat. Nos. 5,324,349; 4,156,616 and 5,279,654 as well as many other surfactants known in the ink jet ink art. Commercial surfactants include the Surfynols® from Air Products; the Zonyls® from DuPont and the Fluorads® from 3M.
Acceptable viscosities are no greater than 20 centipoise, and preferably in the range of about 1.0 to about 10.0, more preferably 1.0 to 5.0 centipoise at room temperature.
The ink has physical properties compatible with a wide range of ejecting conditions, i.e., driving voltages and pulse widths for thermal ink jet printing devices, driving frequencies of the piezo element for either a drop-on-demand device or a continuous device, and the shape and size of the nozzle.
Other ingredients are also commonly added to ink jet inks. A humectant, or co-solvent, is commonly added to help prevent the ink from drying out or crusting in the orifices of he printhead. A penetrant may also be optionally added to help the ink penetrate the receiving substrate, especially when the substrate is a highly sized paper. A biocide, such as Proxel® GXL from Zeneca Colours may be added at a concentration of 0.05-0.5 weight percent to prevent unwanted microbial growth which may occur in the ink over time. Additional additives which may optionally be present in ink jet inks include thickeners, conductivity enhancing agents, anti-kogation agents, drying agents, and defoamers.
The ink jet inks provided by this invention are employed in ink jet printing wherein liquid ink drops are applied in a controlled fashion to an ink receptive layer substrate, by ejecting ink droplets from the plurality of nozzles, or orifices, in a print head of ink jet printers.
Commercially available ink jet printers use several different schemes to control the deposition of the ink droplets. Such schemes are generally of two types: continuos stream and drop-on-demand.
In drop-on-demand systems, a droplet of ink is ejected from an orifice directly to a position on the ink receptive layer by pressure created by, for example, a piezoelectric device, an acoustic device, or a thermal process controlled in accordance with digital data signals. An ink droplet is not generated and ejected through the orifices of the print head unless it is needed. Ink jet printing methods, and related printers, are commercially available and need not be described in detail.
The following examples further clarify the invention.
COMPARATIVE EXAMPLE A
Mill Grind
______________________________________Mill Grind______________________________________Polymeric beads, mean diameter of 50 μm (milling media) 325.0 gBlack Pearls 880 (Cabot Chemical Company) (pigment black 30.0 gOleoyl methyl taurine, (OMT) sodium salt 10.5 gDeionized water 209.5 gProxel GLX (biocide from Zeneca) 0.2 g______________________________________
The above components were milled using a high energy media mill manufactured by Morehouse-Cowles Hochmeyer. The mill was run for 8 hours at room temperature. An aliquot of the above dispersion to yield 2.0 g pigment was mixed with 5.0 g diethylene glycol, 5.0 g glycerol, and additional deionized water for a total of 100.0 g. This ink was filtered through 3-μm filter and introduced into an empty Hewlett-Packard 51626A print cartridge. Images were made with a Hewlett-Packard DeskJet™540 printer on medium weight resin coated paper containing a gelatin imaging layer.
The resin coated paper stock was coated with an imaging layer consisting of about 785 mg/ft 2 of lime processed bone gelatin, about 8 mg/ft 2 polystyrene beads (10-14 micron average particle size) and about 4 mg/ft 2 Olin 10 G surfactant.
COMPARATIVE EXAMPLES B-D.
Inks were prepared in a similar manner as described in Comparative Example A. except, the black pigment was replaced by a quinacridone magenta (pigment red 122) from Sun Chemical Co., Hansa Brilliant Yellow (pigment yellow 74) from Hoechst Chemical Co. or Bis(phthalocyanylalumino)tetra-phenyldisiloxane (cyan pigment) manufactured by Eastman Kodak. The inks were printed as in Comparative Example A. and image cracking was noticeable in each sample.
EXAMPLE 1
An ink was prepared in the same manner as that described in Example A, except 10.0 g of 10 wt % solution of 2,3-dihydroxy-1,4-dioxane (DHD) obtained from Kodak Photochemicals was added to the mixture to obtain a final DHD concentration of 1.0 wt %. Images from this ink were very smooth without any signs of image cracking.
EXAMPLES 2 AND 3
Inks were prepared in the same manner as that described in Example 1, except that DHD was replaced with formaldehyde and gluteraldehyde, respectively. Images from these inks were very smooth without any signs of image cracking or starvation lines.
EXAMPLES 4-7
Inks were prepared in the same manner as that described in Example B (pigment red 122 millgrind), except that DHD was added at 0.30 (Example 4), 0.50 (Example 5), 1.0 (Example 6), and 2.0 wt % (Example 7). Images from these inks exhibit no cracking at all concentrations of DHD.
EXAMPLES 8-9
Inks were prepared in the same manner as that described in Example 1, except that the pigment black 7 was replaced with the pigment yellow 74 or the cyan pigment. Images made with these inks exhibited excellent quality without and signs of cracking.
Ink Characterization
The images printed from the examples were evaluated by measuring the optical densities in three area patches with maximum ink coverage, and averaging, using a X-Rite™ Photographic Densitometer.
Waterfastness was determined by immersing samples of printed images in water for 5 minutes and the allowing to dry for at least 12 hours. The optical density was measured before immersion in water and after immersion in water and drying. Waterfastness is determined as the percent of retained optical density after immersion in water and drying.
Table 1. All examples are summarized in the following table.
TABLE 1______________________________________ % % Density Density RetainedExample Pigment Pigment Additive Before After Density______________________________________Comp. A p.b. 7 2.0 none 2.19 1.85 84.47Comp. B p.r. 122 3.0 none 2.02 0.45 22.28Comp. C p.y. 74 2.5 none 1.79 0.76 42.46Comp. D cyan 2.5 none 2.27 1.06 46.701 p.b. 7 2.0 DHD 2.15 2.14 99.532 p.b. 7 2.0 Formal- 2.32 2.32 100.0 dehyde3 p.b. 7 2.0 Gluter- 2.60 2.36 90.77 aldehyde4 p.r. 122 3.25 DHD 2.15 2.03 94.425 p.r. 122 3.25 DHD 2.16 2.05 94.916 p.r. 122 3.25 DHD 2.22 2.17 97.757 p.r. 122 3.25 DHD 2.15 2.05 95.358 p.y. 74 2.5 DHD 1.82 1.81 99.459 cyan 2.5 DHD 2.27 2.06 90.75______________________________________ p.b. 7 = pigment black No. 7 (Black Pearls 880, Cabot Chemical Co.) p.r. 122 = pigment red No. 122 (Quinacridone Magenta, Sun Chemical Co.) p.y. 74 = pigment yellow No. 74 (Hansa Brilliant Yellow, Oechst Chemical Co.) cyan = Bis(phthalocyanylalumino)tetra phenyldisiloxane DHD = 2,3dihydroxy-1,4-dioxane
The results indicate that significant enhancement of the waterfastness of printed images, printed on glossy papers and films, can be achieved with the addition of a compound containing aldehyde functionality such as 2,3-dihydroxy-1,4-dioxane(DHD), formaldehyde, gluteraldehyde and the like to the ink jet ink.
The invention has been described in detail with particular reference to certain preferred embodiments thereof, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention. | Herein is disclosed a liquid ink jet ink comprising a carrier, a pigment and a compound having an aldehyde functional group. | 2 |
FIELD OF THE DISCLOSURE
[0001] The present disclosure relates to a wire rack for mounting an iron on a wall and method of use thereof, and more specifically, to a wire rack for mounting an iron on a wall, the wire rack having a retractable rail for adjusting to different sizes of irons to be mounted on a wall and equipped with an ironing board holder and a product holder.
BACKGROUND
[0002] Articles of clothing, upholstery, and other fabrics used in households are typically made of fibers that wrinkle during washing, pressing, and handling. Clothing can also wrinkle when worn or manipulated. Shirts are tucked into pants and worn in contact with the skin, and seat covers of a couch are constantly compressed in a certain direction. Winter clothing is also sometimes stored in boxes or depressurized bags that create unwanted wrinkles. Wrinkle-free clothing and fabrics are generally preferred for aesthetical reasons.
[0003] Metal pans filled with charcoal were used in the first century BCE in China to flatten fabrics. In the early 20th century, iron boxes filled with coal were sold in the United States, but this technology was never widely accepted. In the 17th century, delta-shaped tools of cast iron began to be used. These tools had a front nose and a back heel and were placed on a fire with a removable wooden handle. While irons have slowly become almost exclusively stainless steel models, the name “iron” survived changes in materials technology. Ironing boards used in conjunction with irons were also developed during the 20th century. U.S. Pat. No. 19,390 to Vandenburg et al. teaches a primitive version of an ironing board for shirts. The most successful and widely used iron design today is the electric iron, which is heated by a resistive heating element and was invented in 1882 by Henry W. Seeley.
[0004] Wrinkle-free surfaces are desirable for a variety of functional reasons, such as enabling the pearling of water over surfaces; for aesthetical reasons, such as providing the illusion that a piece of clothing is new; and for comfort reasons, as in the case with freshly ironed bed sheets or table linens. Wrinkles are removed by ironing or smoothing a tissue or clothing. Fabrics are heated or pressurized during the ironing process to straighten fibers using the weight of the iron and the additional pressure of the arm of a user. Pressure, heat, and humidity are used jointly to smooth clothing and other fabrics. Some fabrics, such as silk, are heat sensitive and can be damaged if ironed improperly. Light wool also requires extra care, since the fibers are delicately interwoven and weak. Some fabrics, such as cotton, require the addition of water to loosen intermolecular bonds and facilitate ironing.
[0005] Most households place so much importance on ironing that it has become a routine step in the weekly laundry cycle. Ironing can be time consuming and requires equipment such as an iron, an ironing board, and surface treatment products. This troublesome task, much like folding clothes, has remained virtually unchanged over the past decades, and for this reason, improvements hold great commercial value.
[0006] Lighter irons are easier to handle but require more hand pressure to operate. Light irons are also quicker to heat but do not have lengthy internal thermal inertia that allows the surface temperature to remain unchanged when placed over a humid article of clothing. Heavier irons are often difficult to manipulate and must be stored in locations away from where they might potentially cause harm. Virtually all types of iron must be stored between uses, since households rarely have dedicated floor space or laundry rooms dedicated to ironing and handling clothing. U.S. Pat. No. 4,909,158 to Sorensen and Chinese Patent No. 1,202,339 teach the use of a combined wall cabinet equipped with a retractable ironing board fixed within the cabinet and folded up for storage. These devices do not permit users to purchase readily available ironing boards. Further, these devices are bulky and require affixing a heavy cabinet to a wall at a dedicated location. Users of these devices are also limited in their range of operation of the ironing boards. For instance, an operator is unable to access the back of the board. These devices also force users to remain in a stationary location. Other devices described in International Patent Application PCT/NL01/00129 to Okkerse and U.K. Patent Application GB 2,411,906 describe iron holders placed horizontally or attached to the ironing board to allow a hot iron to be held safely between uses or while the fabric is being repositioned. Neither of these devices is directed to short- or long-term storage of ironing boards and irons. U.S. Pat. No. 7,004,433 to Clausen et al. teaches the installation on a wall of two different superimposed components: a board holder and a iron holder. A board holder is attached to the wall in a first step and a iron holder made of one single large tab is then locked into place over the board holder. By holding the iron by the handle at a single point, irons may be damaged by their own weight and the iron may wobble in place since it is not fixed to the holder. Clausen et al. teaches a device unable to hold or adapt to different types of irons. The device as shown is bulky, heavy, and expensive to produce. The device is also incapable of holding extra ironing products or an ironing board constructed without a T-shaped foot.
[0007] What is needed is a light, adjustable device able to hold different types and geometries of irons without causing damage to the iron and able to be installed on a wall in a single operation. What is also needed is a device able to hold extra ironing products and equipped to hold ironing boards of different geometries in a limited space. What is also needed is a cost-effective, heat-resistant device able to provide the above-mentioned improvements.
SUMMARY
[0008] The present disclosure relates to a wire rack for mounting an iron on a wall and method of use thereof, and more specifically, to a wire rack for mounting an iron on a wall, the wire rack having a retractable rail for adjusting to different sizes of irons and equipped with an ironing board holder and a product holder. The iron holder holds the iron by the iron's base and can be adjusted to accommodate different sizes of irons. The frame is also made of heat-resistant, coated, welded wire that allows for the manufacture of a light, cost-effective device. The device is also equipped with large hooks to hold most types of ironing boards and arms designed to hold extra products used during ironing.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is a perspective view of a wire rack for mounting an iron on a wall according to a first embodiment of the disclosure and equipped with a movable heel segment according to a possible embodiment.
[0010] FIG. 2 is a perspective view of the wire rack of FIG. 1 showing in phantom lines the iron, ironing board, and extra products to be held by the wire rack according to a possible embodiment.
[0011] FIG. 3 is an exploded view of the wire rack of FIG. 1 according to a possible embodiment.
[0012] FIG. 4 is a perspective view of the wire rack equipped with a movable nose segment according to a second possible embodiment.
[0013] FIG. 5 is an exploded view of the wire rack of FIG. 4 according to a possible embodiment.
[0014] FIG. 6 is a block diagram of a method for storing ironing equipment according to a possible embodiment.
DETAILED DESCRIPTION
[0015] FIG. 1 shows a perspective view of the wire rack 100 according to a first embodiment of the disclosure equipped with a movable heel segment 12 according to a possible embodiment. FIG. 2 shows the wire rack 100 for mounting an iron 4 with phantom lines showing possible extra products, water storage, containers, and ironing boards placed upon the wire rack 100 . The body 10 comprises a wall mount 22 as shown in FIG. 1 adapted to secure the wire rack to a wall (not shown). The wire rack 100 has a movable torso 11 adapted to secure the iron 4 to the wire rack 100 with a retractable rail 35 having an upper holder 23 adapted for engaging a nose portion of the iron 4 (shown as the pointed end), and a lower holder 24 adapted for engaging the heel portion of the iron (shown as the flat end). The wire rack also includes an arm 19 disposed on the body 10 adapted to hold extra equipment 2 and a leg 15 disposed on the body 10 adapted to hold an ironing board 1 . The retractable rail 35 comprises intermediate positions located on horizontal segments 17 a , 17 b , etc. for moving the upper holder 23 and the lower holder 24 in relation to each other.
[0016] What is shown in FIG. 1 is a wire rack 100 with an essentially rectangular body 10 with different vertical and horizontal elements attached thereto. For example, a horizontal support brace 18 serves together with the arms 19 to hold extra equipment 2 and is fixed across the body 10 to increase the rigidity of the body 10 . In one preferred embodiment, a wall mount 22 is located on the top center portion of the wire rack 100 . Other wall mounts 34 are also shown and may be used if more support is needed. What is contemplated is the use of a wire rack of any type of geometry capable of giving the wire rack 100 sufficient rigidity to maintain its functions of holding an iron 4 , an ironing board 1 , and extra equipment 2 . What is also contemplated is the use of any type of wall mount 22 or 34 located at any position on the body 10 to affix the wire rack 100 to a vertical surface. What is also contemplated is the use of any type of mounting technology, such as but not limited to bolts, nails, screws, legs, magnets, tabs, and the like. In the disclosed embodiment and as shown in FIG. 2 , two legs 15 hold a board 1 using the legs tubes 40 of the ironing board 1 . It is understood that ironing boards 1 can have legs of different geometries based on consumer preferences and market production. What is contemplated in one disclosed embodiment is the use of legs 15 with a protector 16 curved upward to hold the leg tubes 40 of the ironing board 1 . It is understood by one of ordinary skill in the art that the size and orientation of the legs 15 may be modified to hold other types of ironing boards 1 . What is also contemplated is the use of a single leg 15 or a plurality of legs 15 to achieve the same result. While the legs 15 are shown attached to the lower outside corners of the body 10 , what is contemplated is the placement of legs 15 at any reasonable location to hold an ironing board 1 located below the wire rack 100 .
[0017] FIG. 1 also discloses the use of two arms 19 located on each side of the wire rack 100 and attached to vertical wires. While one possible embodiment is shown, what is contemplated is the use of arms 19 located at any reasonable orientation on the wire rack 100 to hold extra equipment 2 . FIG. 2 shows a configuration where two circular arms 19 hold spray cans 2 and a top arm 32 holds a small box 3 . The arm 19 is shown with a bottom wire 20 serving to hold vertically the spray can while the top arm 32 is shown without a bottom wire. What is contemplated is the use of wire technology or other flat surface technology to produce and place on the body 10 any reasonable amounts and types of holders designed to hold the different extra equipment 2 , 3 used during ironing. In the preferred embodiment, the wire rack 100 weighs approximately 13 oz, or less than one pound, and is about 14 inches wide by 14 inches high with a thickness of about 4 inches. The wire rack 100 in a preferred embodiment is made of formed steel wires of 1/16th inch in diameter or of other smaller diameters and is coated with a white, polymer-based thermoplastic. While one preferred embodiment is shown and disclosed in FIGS. 1-3 , and a second preferred embodiment is shown and disclosed in FIGS. 4-5 , what is contemplated is any type of wire rack 100 of any color, with any type of coating or even made of bare stainless steel, capable of holding the different elements disclosed within the same volume and of approximately the same weight. What is also disclosed is the use of thicker wires to form the body 10 and smaller wires to serve as the secondary features placed upon the body 10 in order to reduce the overall weight and manufacturing cost of the wire rack 100 .
[0018] The wire rack 100 has a movable torso 11 adapted to secure the iron 4 to the wire rack 100 with a retractable rail 35 having an upper holder 23 adapted for engaging a nose portion of the iron 4 (shown as the pointed end) and a lower holder 24 adapted for engaging the heel portion of the iron (shown as the flat end). FIG. 3 shows an exploded view of one possible embodiment of the lower holder 24 located on a movable segment 12 of the torso 11 adapted to attach to a horizontal spacing bar 17 a , 17 b on a fixed segment of the torso. The movable segment 12 has a fixation device 13 , shown in FIG. 3 as two hooks, capable of interlocking with one of the horizontal spacing bars 17 a , 17 b , etc. In the preferred embodiment as shown in FIG. 3 , a handful of horizontal spacing bars 17 a , 17 b allow the lower holder 24 to be placed at different distances from the upper holder 23 based on the spacing of the horizontal spacing bars 17 a , 17 b . The movable segment 12 also has lateral tabs 14 used to hold the iron 4 in place laterally as shown in FIG. 2 . The movable segment 12 includes a structural member 25 to increase the overall strength and rigidity of the movable segment 12 and acts as part of the structure placed between the bottom of the iron 4 and the wall (not shown). The lateral legs 14 as shown in FIGS. 1-3 may also be placed on the body 10 as shown in another embodiment in FIGS. 4-5 .
[0019] In the embodiments shown in FIGS. 1-5 , the lower holder 24 is made of a flat wire of rectangular shape and the upper holder 23 is made of a curved 33 wire adapted to receive a pointed nose section of an iron 4 . In these embodiments, a user inserts the nose portion of the iron 4 inside the upper holder 23 and locks the nose behind the curved wire 33 . Once the nose is locked, the heel portion of the base is then slid into the lower holder 24 without risk of falling since the top portion of the iron 4 is already locked in place. While one possible configuration of the upper holder 23 and the lower holder 24 is shown, what is contemplated is any type of upper holder 23 and lower holder 24 based on the existing and preferred geometries of commercial irons in the marketplace. For example, if an iron with two noses is commercialized, the upper holder 23 would be made of two different curves 33 . What is also contemplated is the use of any other fixation device to hold the iron 4 in place on the body 10 , including but not limited to magnets, rotating tabs, clipped on parts, sliding parts, and the use of external fixation means.
[0020] In another embodiment shown in FIGS. 4-5 , the wire rack 100 includes an upper holder 23 located on a movable segment 12 of the torso 11 adapted to repose on a segment of a vertical spacing bar 26 on a fixed segment of the torso 11 . FIGS. 4-5 show a series of fixed steps 17 a , 17 b , 17 c , corresponding to the horizontal spacing bars 17 a , 17 b , 17 c in FIGS. 1-3 , which serve the same function of allowing the movable segment 12 to be placed at regular intervals along the torso 11 on the rail 35 . In the embodiment shown in FIGS. 4-5 , the movable segment 12 is not hooked in place but bent into place into the sliding position shown in FIG. 5 . The upper holder 23 is then pushed down as shown by the arrows in FIG. 5 to secure the iron in place. The use of a bent segment with spaced steps 17 a , 17 b , 17 c instead of the horizontal spacing bars is one of many possible embodiments associated with spacing adjustable structures associated with wire frame technology. It is understood that the following disclosure contemplates any possible adjustable technology.
[0021] Finally, FIG. 6 teaches a method for storing ironing equipment, the method comprising the steps of placing a wire rack on a wall 140 , selecting an intermediate position on the retractable rail at a distance sufficient to hold the iron between the upper and lower holders 141 , positioning the lower holder in relation to the upper holder at a distance sufficient to hold the iron 142 , inserting the iron between the upper and lower holders 143 , suspending an ironing board on the legs 144 , and finally, placing extra equipment in the arms 145 .
[0022] It is understood by one of ordinary skill in the art that these steps correspond to the general steps to be taken to practice this method of this disclosure. Other auxiliary steps may be taken to store ironing equipment, but they do not affect the validity and completeness of the disclosure of this general method. Persons of ordinary skill in the art appreciate that although the teachings of the disclosure have been illustrated in connection with certain embodiments and methods, there is no intent to limit the invention to such embodiments and method. On the contrary, the intention of this application is to cover all modifications and embodiments falling fairly within the scope of the teachings of the disclosure. | The present disclosure relates to a wire rack for mounting an iron on a wall and method of use thereof, and more specifically, to a wire rack for mounting an iron on a wall, the wire rack having a retractable rail for adjusting to different sizes of irons and equipped with an ironing board holder and a product holder. The iron holder holds the iron by the iron's base and can be adjusted to accommodate different sizes of irons. The frame is also made of heat-resistant, coated, welded wire that allows for the manufacture of a light, cost-effective device. The device is also equipped with large hooks to hold most types of ironing boards and arms designed to hold extra products used during ironing. | 3 |
BACKGROUND OF THE INVENTION
[0001] The invention relates to a steering mechanism for a motor vehicle, including a steering wheel which is connected by way of a shaft to a steering gear.
[0002] DE 35 27 236 A1 discloses a steering mechanism which includes a pinion and a steering rack arranged in a steering gear housing. A friction structure is provided for absorbing shocks effective on the steering rack. In this way, rotational steering wheel vibrations caused by wheel flutter are dampened. The friction structure comprises an engagement ring arranged on the steering wheel shaft and a friction disc pressed against the engagement ring. The engagement force is determined by a spring under tension.
[0003] It is the object of the present invention to provide an arrangement for damping oscillations in vehicle steering systems which do not need additional friction structures.
SUMMARY OF THE INVENTION
[0004] In a steering mechanism for a motor vehicle having a steering wheel with a steering shaft connected to a steering gear arrangement, the steering shaft comprises a first vibration damping element for accommodating and attenuating vibrations with relatively low amplitudes as they are generated by uneven road surfaces and a second element having lower damping characteristics than the first element for the transmission of steering movements from the steering wheel to the steering gear arrangement.
[0005] In the steering mechanism according to the invention, the shaft comprises two elements. The first element is provided for generating an uncoupling of the steering wheel from vibrations in the steering gear, which are caused by unevenness of the road surface. The second element has essentially the purpose of transferring steering torques occurring during operation of the motor vehicle. For this reason, a rotationally rigid metallic material is to be used for the second element which has smaller damping characteristics than the first element. Preferably, the shaft according to the invention provides for oscillation damping and a safe torque transmission.
[0006] In one embodiment of the invention, the first element is deformed when torsion impulses with small amplitudes occur and dampens oscillations. Torsion impulses with small amplitude are to be understood to be caused by the road surface. These small oscillations or vibrations which do not affect the travel direction of the vehicle result in a deformation of the first element so that the oscillations are damped and are uncoupled from the steering wheel in an advantageous way.
[0007] In a particular embodiment, the first element consists of a vibration damping elastomer material. An elastomer material is elastic; at the same time, it has good damping properties by an inner friction in the material.
[0008] In a further embodiment of the invention, the second element has no, or only very small, spring rates with impulses of small amplitudes. For properly utilizing the damping properties of the first element, the second element should, with a parallel arrangement of the first and the second element, have only a small spring stiffness in connection with small vibration amplitudes. In this way, it is ensured that the damping properties of the first element dominate the elastic influences of the second element and an effective vibration damping is achieved.
[0009] In another embodiment of the invention, the second element has a larger spring rate with large amplitudes or movements as they occur for the transfer of a steering motion as it has with small oscillation.
[0010] Such larger amplitudes or motions, that is larger angular displacements of the second element relative to the first element, occur for example with a rotation of the steering wheel for changing the travel direction. In order to be able to safely transfer the steering motion or torque from the steering wheel to a pinion of the steering gear, the second element has to have a sufficient spring stiffness.
[0011] In a particular embodiment, the second element is in the form of a slotted tube. The slot closes under a certain torsion force and, with the slot closed, the spring rate increases substantially. With the slotted tube, a two-stage characteristic spring performance line for torsion loads is obtained in a simple manner. As long as the slot is open, the spring stiffness of the tube is small in connection with small torsion loads. As a result, with a parallel arrangement of the first and the second element, in this operating range, the damping properties of the first element prevail. As soon as, with a predetermined torsion moment, the slot of the tube is closed the spring stiffness is suddenly increased. In this operating range, the characteristic spring performance line of the tube determines the spring properties of the shaft.
[0012] In a particular embodiment of the invention, the first element is arranged within the tubular second element in a parallel arrangement and is firmly connected to the second element. With the arrangement of the first element within the second element, the parallel arrangement is achieved in a simple manner. The first element is firmly cemented or vulcanized to the inside wall of the tube.
[0013] In another embodiment, the first and the second elements are arranged in series. Because of the series arrangement and the larger differences with regard to the rotational rigidity between the first and the second element, it is ensured that at first, the first and the second element and, with increasing torque moments, the second element are deformed. Torsion vibrations, that is, vibrations with small amplitudes therefore result mainly in a deformation of the first element for damping vibrations. In a further embodiment of the invention, the first element is rotatable relative to the second element by a predetermined angle while, with larger angular displacements exclusively the second element is rotated. The torque transmission capability of the first element is limited. The first element cannot transmit the maximum steering torque. Therefore, the first element is subjected to a torque only to a certain angular displacement beyond which torques are transmitted by the second element. In this way, the first element is protected from excessive loads in an advantageous manner.
[0014] In a further embodiment of the invention, the shaft is a torsion rod of a power steering arrangement which, dependent on the angular twisting of the torsion rod generates an auxiliary steering force. Torsion rods are provided in power steering systems for sensing steering torques. Depending on the twisting angle of the torsion rod a hydraulic auxiliary force may be provided wherein a steering valve admits a pressurized fluid to a cylinder piston unit depending on the twist angle of the torsion rod. In the same way, a torsion rod may be utilized with an electrical power steering system: An electric sensor measures the twisting of the torsion rod and an electric motor generates a torque supporting the steering movement depending on the twisting angle of the torsion rod.
[0015] Other features and feature combinations will become apparent from the following description on the basis of the accompanying drawings. Actual embodiments of the invention are shown in the drawings in a simplified schematic representation.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 shows schematically a vehicle steering system,
[0017] FIG. 2 is a longitudinal cross-sectional view of a steering valve unit,
[0018] FIGS. 3 and 3 a show in longitudinal and transverse cross-sectional views a section of a torsion rod according to the invention,
[0019] FIG. 4 shows the characteristic performance lines for a torsion rod according to the invention and a conventional torsion rod, and
[0020] FIGS. 5 and 5 a show a particular embodiment of a torsion rod according to the invention in longitudinal and transverse cross-sectional views.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0021] Identical components are designated in the various figures by the same reference numerals.
[0022] FIG. 1 shows a steering system according to the invention for a motor vehicle, which is not shown. A steering shaft 2 transmits the steering moment applied by a driver to the steering wheel 1 to an input shaft 3 of a steering gear 16 .
[0023] The steering gear 16 comprises a housing in which a pinion 8 and a steering rack 9 are disposed. The pinion 8 is operatively connected to the input shaft 3 and engages the steering rack 9 . This arrangement converts the rotational movement of the input shaft 3 , or respectively, the pinion 8 into a linear movement of the steering rack 9 . The steering rack 9 is connected to the front wheels 6 by way of left and right end connecting rods 7 . Depending on the direction of movement of the rack 9 , the front wheels 6 are steering the vehicle to the left or to the right. The steering gear 16 is further connected to a double-sided cylinder piston unit 10 , which is coupled with the steering rack 9 . A steering valve 4 controls the hydraulic oil supply to the cylinder piston unit 10 depending on the steering moment. Next to the schematic representation of the steering valve 4 , FIG. 1 shows a symbolized block representation of the steering valve 4 using arrows for a better understanding of the operation.
[0024] A mechanically or electrically driven power steering pump 12 generates the oil pressure required for the power steering. The power steering pump 12 pumps oil from a tank 11 by way of a supply line with a check valve 13 to the steering control valve 4 and from there by way of pressure lines 15 to the cylinder piston unit 10 of the power steering unit 16 . The oil is returned to the tank 11 via a return line. In a modified embodiment, the oil circuit includes a pressurized oil storage 14 . If the power steering pump 12 fails, then there is some power steering still available for some time.
[0025] FIG. 2 shows in a sectional view, the steering valve 4 in principle. A shaft 20 in the form of a torsion rod arranged in a steering valve housing 21 is connected at one end to the input shaft 3 shown in FIG. 1 and, at the other end, to the pinion shaft 24 , or respectively, the pinion 8 of the steering gear unit 16 . At the end of the input shaft 3 , the torsion rod 20 is connected to a control spool 22 , which includes control grooves 23 . The pinion shaft 24 is connected to a control sleeve 25 . In the assembled state of the steering valve 4 , the control spool 22 the torsion rod 20 extends through the control spool 22 and the control spool 22 is surrounded by the control sleeve 25 which is arranged in the steering housing 21 . The torsion rod is twisted under load and, because of this torsion twisting the control spool 22 rotates with respect to the control sleeve 25 , which is connected to the pinion shaft 24 . The control grooves 23 provided in the control spool 22 therefore are rotated with respect to the hydraulic oil admission openings, which are arranged in the control sleeve 25 but are not shown in the drawings. Depending on the angle of rotation, the oil flow cross-sections in the steering valve 4 are changed. In this way, a steering moment-dependent pressure control as required for the power steering is obtained.
[0026] FIGS. 3 and 3 a are axial and transverse cross-sectional views of the torsion rod shaft 20 . The torsion rod 20 is connected to the valve spool 22 and the pinion shaft 24 and is of a design as shown in FIGS. 3 and 3 a . The torsion rod 20 comprises a first vibration damping element 27 such as an elastomer core and a second element 26 in the form of a slotted tube 26 , which has low damping properties. The vibration damping element 27 is firmly connected to the inner surface of the slotted tube 26 , for example, by vulcanization. FIG. 4 shows the characteristic performance lines 30 , 29 for a solid metal torsion rod in comparison with a torsion rod 20 according to the invention. The slotted tube 26 is in accordance with the characteristic line 29 very elastic rotationally up to a twist angle φ, where the slot 28 closes, that is, a small torsion moment Mt is sufficient to twist the tube 26 to the angle φ, sec range 31 . Starting at the twist angle φ, the slot 28 is closed and the torsional rigidity of the tube 26 increases in the range 32 so that up to the maximum twist angle φ max , a torsion moment corresponding to the characteristic line 30 is followed that is like with the torsion rod of solid design.
[0027] A vibration caused by the wheels 6 as a result of uneven road surfaces is passed on via the rack 9 , the pinion 8 and the torsion rod 20 to the steering wheel 1 . The rotational vibration occuring at the steering wheel 1 , called shimmy, can be reduced by the torsion rod according to the invention. The vibrations occurring as shimmy have generally a small amplitude. Under such a load, the torsion rod 20 behavior is defined by the area 31 of the characteristic line 29 of FIG. 4 . As a result of the twisting of the vibration damping element 27 , the vibration is attenuated and is not transmitted to the steering wheel 1 . With small vibration amplitudes, the elastomer 27 arranged in parallel with the tube 26 is rotationally resilient because of the slot 28 so that the spring rigidity of the torsion rod 20 in this operational range is determined essentially by the vibration damping element 27 . As a result, good vibration damping properties can be achieved by which rotational vibrations are rapidly attenuated. For the transmission of torsion moments, such as steering torques which result in a rotation of the torsion rod 20 in excess of the twist angle φ, the rotational rigidity of the torsion rod 20 increases rapidly as shown in FIG. 4 for the range 32 . The increased rotational rigidity provides for a reliable transmission of a steering movement from the steering wheel 1 to the steering gear 16 .
[0028] In an embodiment as shown in FIGS. 5 and 5 a , the torsion rod 20 comprises two parts, a first section 20 ′ and a second section 20 ″. Between the first and the second sections 20 ′, 20 ″, a vibration damping element 27 is arranged. The first torsion rod section 20 ′ includes engagement members 34 , which extends into openings 33 of the second torsion rod section 20 ″.
[0029] If the torsion rod 20 is subjected to a torsion moment, the engagement members 34 are rotated with the torsion rod section 20 ′ relative to the torsion rod section 20 ″ within the rotational limit 35 . As a result, up to a twist angle of φ, essentially only the vibration damping element 27 is twisted. Torsional vibrations which are caused by the road surface and have an amplitude below the twist angle φ, are therefore attenuated and uncoupled from the steering wheel 1 , see the range 31 of the diagram of FIG. 3 . With larger torsion moments such as steering wheel movements, for example, during parking maneuvers the rotational play range is exceeded so that the vibration damping element 27 cannot be further twisted as the engagement members 34 of the first section 20 of the torsion rod 20 directly engage the second section 20 ″.
[0030] The rotational rigidity of the torsion rod 20 then increases as indicated for the range 32 of FIG. 3 . In this range 32 , the torsion rod 20 has the rotational rigidity as required for the transmission of the steering torque from the steering wheel 1 to the steering gear 16 . The power assist for the power steering depending on the steering torque is adjustable or selectable by a selection of the reduction of the diameter of the second section 20 ″ of the torsion rod. | In a steering mechanism for a motor vehicle having a steering wheel with a steering shaft connected to a steering gear arrangement, the steering shaft comprises a first vibration damping element for accommodating and attenuating vibrations with relatively low amplitudes as they are generated by uneven road surfaces and a second element having lower damping characteristics than the first element for the transmission of steering movements from the steering wheel to the steering gear arrangement. | 1 |
FIELD OF THE INVENTION
The invention relates to the field of microbial enhanced oil recovery and bioremediation of subterranean contaminated sites. Specifically, it relates to methods of treating the toxic chemicals accumulated in subterranean sites adjacent to the water injection wells prior to introduction of microbial inocula for microbial enhanced oil recovery or bioremediation of these sites.
BACKGROUND OF THE INVENTION
Traditional oil recovery techniques which utilize only the natural forces present at an oil well site, allow recovery of only a minor portion of the crude oil present in an oil reservoir. Oil well site generally refers to any location where wells have been drilled into a subterranean rock containing oil with the intent to produce oil from that subterranean rock. An oil reservoir typically refers to a deposit of subterranean oil. Supplemental recovery methods such as water flooding have been used to force oil through the subterranean location toward the production well and thus improve recovery of the crude oil (Hyne, N.J., 2001, “Non-technical guide to petroleum geology, exploration, drilling, and production”, 2nd edition, Pen Well Corp., Tulsa, Okla., USA).
To meet the rising global demand on energy, there is a need to further increase production of crude oil from oil reservoirs. An additional supplemental technique used for enhancing oil recovery from oil reservoirs is known as Microbial Enhanced Oil Recovery (MEOR) as described in U.S. Pat. No. 7,484,560. MEOR, which has the potential to be a cost-effective method for enhanced oil recovery, involves either stimulating the indigenous oil reservoir microorganisms or injecting specifically selected microorganisms into the oil reservoir to produce metabolic effects that lead to improved oil recovery.
The production of oil and gas from subterranean oil reservoirs requires installing various equipment and pipelines on the surface or the subterranean sites of the oil reservoir which come in contact with corrosive fluids in gas- and oil-field applications. Thus, oil recovery is facilitated by preserving the integrity of the equipment needed to provide water for water injection wells and to convey oil and water from the production wells. As a result, corrosion can be a significant problem in the petroleum industry because of the cost and downtime associated with replacement of corroded equipment.
Sulfate reducing bacteria (SRB) microorganisms, which produce hydrogen sulfide (H 2 S), are amongst the major contributors to corrosion of ferrous metal surfaces and oil recovery equipment. These microorganisms can cause souring, corrosion and plugging and thus can have negative impact on a MEOR or a bioremediation process. Bioremediation refers to processes that use microorganisms to cleanup oil spills or other contaminants from either the surface or the subterranean sites of soil.
To combat corrosion, corrosion inhibitors which are chemicals or agents that decrease the corrosion rate of a metal or an alloy and are often toxic to microorganisms, are used to preserve the water injection and oil recovery equipment in such wells. In the practice of the present invention a water injection well is a well through which water is pumped down into an oil producing reservoir for pressure maintenance, water flooding, or enhanced oil recovery. The significant classes of corrosion inhibitors include compounds such as: inorganic and organic corrosion inhibitors. For example, organic phosphonates, organic nitrogen compounds, organic acids and their salts and esters (Chang, R. J. et al., Corrosion Inhibitors, 2006, Specialty Chemicals, SRI Consulting).
US2006/0013798 describes using bis-quaternary ammonium salts as corrosion inhibitors to preserve metal surfaces in contact with the fluids to extend the life of these capital assets.
U.S. Pat. No. 6,984,610 describes methods to clean up oil sludge and drilling mud residues from well cuttings, surface oil well drilling and production equipment through application of acids, pressure fracturing and acid-based microemulation for enhanced oil recovery.
WO2008/070990 describes preconditioning of oil wells using preconditioning agents such as methyl ethyl ketone, methyl propyl ketone and methyl tertiary-butyl ether in the injection water to improve oil recovery. Mechanisms such as modifying the viscosity of the oil in the reservoir and enlivening the heavy oil were attributed to this method.
US2009/0071653 describes using surfactants, caustic agents, anti-caking agents and abrasive agents to prevent or remove the build-up of fluid films on the processing equipment to increase the well's capacity.
Studies indicate that long-term addition of chemicals or agents used to control undesirable events such as corrosion, scale, microbial activities, and foam formation in the water supply of a water injection well does not lead to their accumulation in high enough concentrations to adversely affect the microorganisms used in MEOR (Carolet, J-L. in: Ollivier and Magot ed., “Petroleum Microbiology”, chapter 8, pages 164-165, 2005, ASM press, Washington, D.C.).
However, viability of microorganisms used in MEOR or bioremediation processes is a concern. It can be desirable to modify MEOR or bioremediation treatments such that the viability of microorganisms used is maintained throughout the process thus making them more effective.
SUMMARY OF THE INVENTION
The present disclosure relates to a method for improving the effectiveness of a MEOR or bioremediation process by detoxifying subterranean sites adjacent to oil wells, wherein the wells have been previously treated with corrosion inhibitors prior to inoculation of the microorganisms required for MEOR or bioremediation.
In one aspect the present invention is an oil recovery method comprising the steps of:
a) treating a subterranean site in a zone adjacent to a water injection well with a detoxifying agent wherein, prior to the treatment, corrosion inhibitors and/or their degradation products have been adsorbed into the zone and have accumulated to concentrations that are toxic to microorganisms used in microbial enhanced oil recovery and/or bioremediation processes, and thereby have formed a toxic zone; and b) adding an inoculum of microorganisms to the water injection well wherein the microorganisms comprise one or more species of: Comamonas, Fusibacter, Marinobacterium, Petrotoga, Shewanella, Pseudomonas, Vibrio, Thauera , and Microbulbifer useful in microbial enhanced oil recovery;
wherein the corrosion inhibitor is an inorganic compound selected from the group consisting of chlorine, hypochlorite, bromine, hypobromide, chlorine dioxide, hydrazine, anthraquinone, phosphates, and salts containing chrome, molybdenum, zinc, nitrates, nitrites and sodium sulfite.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 is the schematic representation of a water injection well and the subterranean sites adjacent to the water injection well. ( 1 ) is the flow of injection water into the well casing ( 7 ), ( 2 and 3 ) are rock layers, ( 4 ) is the perforations in the casing, ( 5 ) is the well bore, ( 6 ) is the face of the rock layer made by the well bore, ( 7 ) is the well casing, ( 8 ) is one side of the watered zone that is axi-symmetric with the injection well, shown by a dotted box in the rock layer ( 3 ).
FIG. 2 is the schematic of a model system used to simulate formation of a toxic zone. ( 9 ) is a long slim tube; ( 10 ) is a pressure vessel to constrain the slim tube; ( 11 and 12 ) are the opposite ends of the pressurized vessel; ( 13 ) is a pump; ( 14 ) is the feed reservoir; ( 15 ) is the water inlet for the pressure vessel; ( 16 ) is the back pressure regulator; ( 17 ) is the high pressure air supply; ( 18 ) is an inlet fitting connecting the slim tube inside the pressure vessel to the pump and pressure transducers; ( 21 ) is an outlet fitting connecting the slim tube inside the pressure vessel to the back pressure regulator and the low side of the differential pressure transducer; ( 19 ) is a differential pressure transducer; and ( 20 ) is an absolute pressure transducer.
FIG. 3 depicts titration of amine coated core sand; ♦ represent amine coated sand and □ represent first derivative of the titration curve (central differences).
FIG. 4 depicts titration of brine and core sand with 1N HCl; ▪ represent brine #1 with 10 grams of core sand; diamonds ♦ represent brine #1 only; represents the slope of brine #1 with 10 grams of core sand; and Δ represents the slope of brine #1 only.
FIG. 5 depicts titration of brine and core sand with 10% nitric acid; ♦ represent the concentration of amine observed in solution for a given pH.
FIG. 6 depicts titration of brine and core sand with 10% acetic acid; ♦ represent the concentration of amine observed in solution for a given pH.
DETAILED DESCRIPTION OF THE INVENTION
In one aspect, the present invention is a method for detoxifying the corrosion inhibitors and their degradation products in a subterranean site adjacent to a water injection well of an oil well site. Applicants have found that oil recovery processing aids—such as corrosion inhibitors, for example—can accumulate in the area adjacent to the water injection well and build to concentrations that are toxic to microorganisms used in MEOR or bioremediation. As the term is used herein, “detoxifying” or “detoxification of” a water injection site means removing or reducing the toxicity caused by corrosion inhibitors and their degradation products to microorganisms to allow their growth and activity of said microorganisms, used in MEOR or bioremediation.
For the purposes of the present invention, the term “toxic zone” refers to a subterranean site adjacent to the water injection well comprising toxic concentrations of agents such as corrosion inhibitors or their degraded products which have adverse effects on growth and metabolic activities of microorganisms used in MEOR and/or bioremediation. A toxic agent, as the term is used herein, is any chemical or biological agent that adversely affects growth and metabolic functions of microorganisms used in MEOR and/or bioremediation.
FIG. 1 is a schematic of a subterranean site adjacent to a water injection well. The injection water ( 1 ) flows into the well casing ( 7 ) which is inside the well bore ( 5 ) drilled through rock layers ( 2 and 3 ). A gap exists between the well casing ( 7 ) and the face ( 6 ) of the rock layer made by the well bore ( 5 ). Rock layer ( 2 ) represents impermeable rock above and below a permeable rock ( 3 ) that holds or traps the oil. The injection water ( 1 ) flows down the well casing ( 7 ) and passes through perforations in the casing ( 5 ) and into fractures ( 4 ) in the permeable rock ( 3 ). This injection water then flows through the permeable rock layer ( 3 ) and displaces oil from a watered zone ( 8 ) adjacent to the well bore. This zone extends radially out from the well bore ( 5 ) in all directions in the permeable rock layer ( 3 ). While the volume of permeable rock ( 3 ) encompassed by the dash line ( 8 ) is illustrated only on one side of the well bore it actually exists on all sides of the well bore. This watered zone represents the subterranean site adjacent to the water injection well.
Corrosion inhibitors that can accumulate to levels that are toxic to microorganisms used in MEOR are, for example: inorganic corrosion inhibitors such as chlorine, hypochlorite, bromine, hypobromide and chlorine dioxide. Those used to combat corrosion caused by SRB microorganisms include, but are not limited to: nitrates (e.g., calcium or sodium salts), nitrite, molybdate, (or a combination of nitrate, nitrite and molybdate), anthraquinone, phosphates, salts containing chrome and zinc and other inorganics, including hydrazine and sodium sulfite (Sanders and Sturman, chapter 9, page 191, in: “Petroleum microbiology” page 191, supra and Schwermer, C. U., et al., Appl. Environ. Microbiol., 74: 2841-2851, 2008).
Organic compounds used as corrosion inhibitors include: acetylenic alcohols, organic azoles, gluteraldehyde, tetrahydroxymethyl phophonium sulfate (THPS), bisthiocyanate acrolein, dodecylguanine hydrochloride, formaldehyde, chlorophenols, organic oxygen scavengers and various nonionic surfactants.
Other organic corrosion inhibitors include, but are not limited to: organic phosphonates, organic nitrogen compounds including primary, secondary, tertiary or quaternary ammonium compounds (hereinafter referred to generically as “amines”), organic acids and their salts and esters, carboxylic acids and their salts and esters, sulfonic acids and their salts.
Applicants have determined that corrosion inhibitors can accumulate by adsorption into or on the subterranean site (e.g., sand stone, unconsolidated sand or limestone) or into the oil that has been trapped in the oil reservoir subterranean site. Long-term addition of these chemicals results in their accumulation and formation of a toxic zone in subterranean sites adjacent to the water well with adverse effects on microbial inocula intended for MEOR and/or bioremediation applications.
A model system to simulate formation of a toxic zone can be used to study its effects on the survival of microorganisms. For example, a model system called a slim tube can be set up and packed with core sand from an oil well site. The model system as described herein can be set up using tubing, valves and fittings compatible with the crude oil or the hydraulic solution used that can withstand the range of applied pressure during the process. An absolute pressure transducer, differential pressure transducer and back pressure regulator for Example made by (Cole Plamer, Vernon hill, IL and Serta, Boxborough, Mass.) are required and are commercially available to those skilled in the art.
The model toxic zone can be established using solutions of amines and/or amine mixtures and flushing them through a tube packed with core sand from an oil reservoir. Other corrosion inhibitors suitable for use in constructing a model can comprise organic phosphonates or anthraquinone or phosphates. The concentration of the corrosion inhibitors used to create the model toxic zone may be from 0.01 to 100 parts per million.
Detoxification of the toxic zone involves degradation, desorption or dispersion of the accumulated toxic chemicals or agents using detoxifying agents. The term “detoxifying agent” therefore refers to any chemical that either disperses or destroys the toxic chemicals and agents described herein and renders them non-toxic to microorganisms.
Detoxification of the chemicals accumulated in the toxic zone may be achieved using a degradation agent. A degradation agent, as the term is used herein, is an agent that destroys or assists in the destruction of toxic agents found in the toxic zone. Degradation agents can include, for example, strong oxidizers that chemically react with corrosion inhibitors when added to the injection water and degrade them into less toxic or non-toxic products. Degradation agents include strong oxidizing agents such as, for example, nitrates, nitrites, chlorates, percholorates and chlorites.
Detoxification of the chemicals accumulated at the toxic zone may also be achieved using a dispersing agent. A “dispersing agent” as the term is used herein includes any chemical that lowers the pH of the solution, ionizes the amines and solubilizes them into the water during water flooding and allows for natural dispersion and diffusion to lower the concentration where it is no longer toxic to MEOR or bioremediation microorganisms. For example, amines are fairly non-reactive under mild conditions, however, they become ionized at lower pH. Thus treatment of the amines with an acid increases their solubility and releases them from oil and/or from rocks and disperses them from the toxic zone. The solubilized amines may therefore enter into the water flowing through the well. A combination of radial flow, dispersion and desorption may allow the solubilized amines to be diluted and dispersed over a large area (from at least 10 to about 200 feet (from at least 3 meters to about 7 meters)) of the oil well. Following dilution and dispersion of the amines over a much larger area, their concentrations within the subterranean site of the well would have been consequently reduced to non-toxic levels for MEOR or bioremediation microorganisms. However, even if the amines concentrations were still at toxic levels, the toxic zone in the subterranean site adjacent to the injector well will have become non-toxic to microorganisms. Thus, the microbial inoculum may pass through the subterranean site adjacent to the water injection well without encountering toxic levels of the amines.
In another embodiment, hydrogen peroxide may be added to the toxic zone, as both a degradation and a dispersing agent, from about 1,000 parts per million to 70,000 parts per million by volume of water. In another embodiment, perchlorates may be added, as both a degradation and a dispersing agent, from about 1 parts per million to about 10,000 parts per million.
In another embodiment, any acid capable of lowering the pH at least 1 unit less than the equivalence point of the amine (as measured in the Examples below) may be used. The acid used to ionize the amines may include, but is not limited to, nitric acid, acetic acid, oxalic acid, hydrofluoric acid, and hydrochloric acid. Acid may be added from about 0.1 weight % to about 20 weight % to the water that is being pumped into the toxic zone.
In a MEOR process, viable microorganisms are added to the water being injected into the water injection well. The term “inoculum of microorganisms” refers to the concentration of viable microorganisms added. These microorganisms colonize, that is to grow and propagate, at the subterranean sites adjacent to the water injection well to perform their MEOR.
Microorganisms useful for this application may comprise classes of facultative aerobes, obligate anaerobes and denitrifiers. The inoculum may comprise of only one particular species or may comprise two or more species of the same genera or a combination of different genera of microorganisms.
The inoculum may be produced under aerobic or anaerobic conditions depending on the particular microorganism(s) used. Techniques and various suitable growth media for growth and maintenance of aerobic and anaerobic cultures are well known in the art and have been described in “Manual of Industrial Microbiology and Biotechnology” (A. L. Demain and N. A. Solomon, ASM Press, Washington, D.C., 1986) and “Isolation of Biotechnological Organisms from Nature”, (Labeda, D. P. ed. p117-140, McGraw-Hill Publishers, 1990).
Examples of microorganisms useful in MEOR in this application include, but are not limited to: Comamonas terrigena, Fusibacter paucivorans, Marinobacterium georgiense, Petrotoga miotherma, Shewanella putrefaciens, Pseudomonas stutzeri, Vibrio alginolyticus, Thauera aromatics, Thauera chlorobenzoica and Microbulbifer hydrolyticus.
In one embodiment an inoculum of Shewanella putrefaciens (ATCC PTA-8822) may be used to inoculate the slim tube test. In another embodiment Pseudomonas stutzeri (ATCC PTA8823) may be used to inoculate the slim tube. In another embodiment Thauera aromatica (ATCC9497) may be used to inoculate the slim tube.
The inoculum of microorganisms useful for bioremediation may comprise, but are not limited to, various species of: Corynebacteria, Pseudomonas, Achromobacter, Acinetobacter, Arthrobacter, Bacillus, Nocardia, Vibrio , etc. Additional useful microorganisms for bioremediation are known and have been cited, for example, in Table 1 of U.S. Pat. No. 5,756,304, columns 30 and 31.
The inoculum for injecting into the water well injection site may comprise one or more of the microorganisms listed above.
EXAMPLES
The present invention is further defined in the following Examples. It should be understood that these Examples, while indicating preferred embodiments of the invention, are given by way of illustration only. From the above discussion and these Examples, one skilled in the art can ascertain the essential characteristics of this invention, and make various changes and modifications to the invention to adapt it to various uses and conditions.
General Methods
Chemicals and Materials
All reagents, and materials used for the growth and maintenance of microbial cells were obtained from Aldrich Chemicals (Milwaukee, Wis.), DIFCO Laboratories (Detroit, Mich.), GIBCO/BRL (Gaithersburg, Md.), or Sigma Chemical Company (St. Louis, Mo.), unless otherwise specified.
Amines Analysis
Concentration of amines, in media and water, were analyzed by gas chromatography (GC). An Agilent Model 5890 (Agilent, Wilmington, Del.), GC equipped with a flame photoionization detector and a split/splitless injector, a DB-FFAP column (30 meter length×0.32 millimeter (mm) depth×0.25 micrometer particle size). The equipment had an Agilent ALS Autoinjector, 6890 Model Series with a 10 milliliter (ml) syringe. The system was calibrated using a sample of N,N-Dimethyl-1-Dodecaneamine (Aldrich). Helium was used as the carrier gas. A temperature gradient of 50 degrees Celsius (° C.) to 250° C. at 30° C. increase per minute (min) was used. Retention times (in minutes, min) for various chemicals of interest included: N,N-Dimethyl-1-Dodecaneamine (8.08 min); N,N-Dimethyl-1-Tetradecaneamine (8.85 min); N,N-Dimethyl-1-Hexadecane-amine (9.90 min); N,N-Dimethyl-1-Octadecaneamine (10.26 min) and N-Methyl,N-Benzyl)-1-Tetradecaneamine (11.40 min).
Example 1
Establishing a Toxic Zone in Core Sand from an Oil Well Using a Mixture of Amines in a Model System
A sample of the sand obtained from the Schrader Bluff formation at the Milne Point Unit of the Alaska North Slope was cleaned by washing with a solvent made up of a 50/50 (volume/volume) mixture of methanol and toluene. The solvent was subsequently drained and then evaporated off the core sand to produce clean, dry, flow able core sand. This core sand was sieved to remove particles with less than one micrometer in size and was then packed tightly into a four foot (121.92 cm) long flexible slim tube ( 9 ) and compacted by vibration using a laboratory engraver. Both ends of the slim tubes were capped to keep the core sand in it. The complete apparatus is shown in FIG. 2 . Tubing that can sustain the amount of pressures used in the slim tube, was connected to the end caps. The slim tube ( 9 ) was mounted into the pressure vessel ( 10 ) with tubing passing through the ends ( 11 and 12 ) of the pressure vessel using pressure fittings ( 18 and 21 ). Additional fittings and tubing were used to connect the inlet of the slim tube ( 11 ) to a pressure pump ( 13 ) and a feed reservoir ( 14 ).
Additional fittings and tubing connected the inlet of the slim tube to an absolute pressure transducer ( 20 ) and the high pressure side of a differential pressure transducer ( 19 ). Fittings and tubing connected the outlet of the slim tube ( 12 ) to the low pressure side of a differential pressure transducer ( 19 ) and to a back pressure regulator ( 16 ). The signals from the differential pressure and the absolute pressure transducer were ported to a computer and the pressure readings were monitored and periodically recorded. The pressure vessel ( 10 ) around the slim tube was filled with water through a water port ( 15 ). This water was then slowly pressurized with air ( 17 ) to a pressure of about 105 per square inch (psi) (0.72 mega Pascal) while brine #1 from the feed reservoir ( 14 ) (Table 1) flowed through the slim tube and left the slim tube through the back pressure regulator ( 16 ). This operation was performed such that the pressure in the slim tube was always 5 to 20 psi (0.034-0.137 mega Pascal) below the pressure in the pressure vessel ( 10 ).
TABLE 1
Ingredients of Brine #1
(no nutrient brine - gram per liter (gr/L) of tap water
NaHCO 3
1.38
grams (gr)
CaCl 2 *6H 2 O
0.39
gr
MgCl 2 *6H 2 O
0.220
gr
KCl
0.090
gr
NaCl
11.60
gr
NaHCO 3
1.38
gr
Trace metals
1
ml
Trace vitamins
1
ml
Na 3 (PO 4 )
0.017
gr (=10 parts per million (ppm) PO 4 )
NH4Cl
0.029
gr (=10 ppm NH 4 )
Acetate
0.2
gr (200 ppm acetate)
The pH of brine #1 was adjusted to 7.0 with either HCl or NaOH and the solution was filter sterilized.
TABLE 2
Concentration of the amines added to Brine #1
N-methylN-
Minor
other
NN-Dimethyl-1-
NN-Dimethyl-1-
NN-Dimethyl-
Benzyl-1-
amine
amine
Dodecaneamine
tetradecaneamine
Methanethioamide ??
Caprolactam
tetradecaneamine
Sample
PPM
PPM
PPM
PPM
PPM
PPM
PPM
Brine #1 w/amine
25
124
23
1
0
0
2
Once the pressure inside and outside the slim tube was established, one pore volume of the crude oil from an oil reservoir of the Milne Point Unit of the Alaskan North Slope was pumped into the slim tube. This process was performed in several hours (h). Once the crude oil had saturated the core sand in the slim tube and was observed in the effluent, the flow was stopped and the oil was allowed to age in the core sand for 3 weeks. At the end of this time, brine #1 was pumped through the slim tube at a rate of ˜1.5-3.5 milliliter per hour (ml/h) (˜1 pore volume every 20 h). Samples were taken from the effluent and the concentration of natural microflora in them was determined.
After 51 pore volumes of flow through the slim tube the concentration of natural microflora in the system was about 1×10 7 colony forming units per milliliter (CFU/ml). At this point, a mixture of amines (hereafter amines/brine mixture) was added at 150 ppm concentration to brine #1. The approximate composition of the mixture of amines (Table 2) consisted of 7 different amine components that were identified. Five were identified by Mass Spectrometry (Agilent Technologies, Inc. Santa Clara, Calif.) as N-N-dimethyl-1-dodecaneamine, N-N-dimethyl-1-tetradecane-amine, N-N-dimethyl-methane-thioamide, caprolactam and N-methyl-N-benzyl-1-tetradecaneamine. Two of the components were identified as amines but specific chemical formulas could not be assigned to them because the Mass Spectral Fragmentation patterns could not be deciphered. These are labeled in Table 2 as “minor amine” and “other amine”. Analysis of the effluent from the slim tube did not indicate presence of any amines in it. The experiment was continued by pumping 150 ppm of the mixture of amines in brine #1 through the slim tube.
After 77 pore volumes of the mixture of brine #1 with 150 ppm of mixture of amines was pumped into the slim tube no amines were observed in the effluent.
After 80 pore volumes of the mixture of brine #1 with 150 ppm of mixture of amines was pumped into the slim tube a total of about 1 gr of the mixture of amines had flowed through the slim tube. At this point, 80 ppm of amines was finally observed in the effluent of the slim tube. This very long delay in seeing the amines in the effluent means that virtually all the amines had been trapped in the slim tube. In addition, at this time, no natural microflora could be seen in the effluent indicating that the slim tube had become toxic enough to kill all existing microflora. At this point, pumping the amines-free brine#1 was started in an attempt to flush the amines out of the slim tube and to make it less toxic.
After 24 pore volumes of the amines-free brine#1 had been pumped through the slim tube, 51 ppm of amines was detected in the effluent. The slim tube was then inoculated with one pore volume of Shewanella putrefaciens (ATCC PTA-8822) at a concentration of approximately 1×10 9 CFU/ml. This inoculation was not allowed to remain in the slim tube. Instead, amines-free brine#1 was flushed through the slim tube immediately after the inoculation. Consequently the microbes resided in the slim tube for only a few hours during the transit through it. Thus, it was anticipated that the microorganisms' concentration in the effluent could be measured in the effluent eluting the slim tube. However, remarkably no microorganisms (representing about a 9 log kill) were detected in the slim tube effluent despite the short residence time of the inoculum in the slim tube. This experiment confirmed that a toxic zone had been established in the slim tube. In a continued attempt to detoxify the slim tube, brine #1 alone was continuously pumped through it.
After 79 pore volumes of the amines-free brine #1 had been pumped through the slim tube, the amines concentration in the effluent of the slim tube was measured at 30 ppm. The slim tube was inoculated with another pore volume of Shewanella putrefaciens (at 1×10 9 CFU/ml). The CFU/ml in an effluent sample was about 1×10 4 showing more than a 5 log kill of this microorganism had occurred immediately following inoculation. This experiment underlined the continued toxic effect of the amines despite extended washing of the tube with the amines-free brine#1 solution.
After 108 pore volumes of the amines-free brine #1 had been pumped through the slim tube, the amine concentration in the effluent was measured at 5 ppm. The slim tube was inoculated with an additional one pore volume of Shewanella putrefaciens containing 1×10 9 CFU/ml. The CFU/ml in the effluent sample of the slim tube immediately following inoculation indicated a 4-5 log kill of this microorganism despite the extended washing with the amines-free brine#1 and the decrease in the amines concentration in the effluent. These results further confirmed the continued toxic effect of the mixture of amines accumulated in the slim tube.
After 143 pore volumes of the amines-free brine #1 had been pumped through the slim tube one pore volume of an inexpensive odorless mineral spirits (OMS) (Parks OMS, Zinsser Co., Inc., Somerset Jew Jersey #2035 CAS #8052-41-3) was pumped through the slim tube in an attempt to remove the remaining mixture of amines. After this flush of OMS, pumping of amines-free brine #1 through the slim tube was continued.
After 149 pore volumes of amines-free brine #1 had been pumped through the slim tube, the amines concentration in the effluent was measured at 4 ppm and the slim tube was inoculated with an additional one pore volume of Shewanella putrefaciens (1×10 9 CFU/ml). A count of microorganisms in the sample of the slim tube's effluent showed a 2-3 log kill (99 to 99.9%) despite the OMS flush and the extended washing with the amines-free brine#1. These results confirmed that the toxic zone in the slim tube was still killing virtually all the microorganisms added to the tube.
After 168 pore volumes of the amines-free brine #1 had been pumped through the slim tube, one pore volume of a solution of 10% HCl in water was pumped through the slim tube to remove the amines. After this acid wash, the amines-free brine #1 was continuously pumped through the slim tube.
Following the acid wash treatment, an additional 2 pore volumes of the amines-free brine #1 was pumped through the slim tube and the amines concentration in the effluent was measured at 0.5 ppm. The slim tube was then inoculated with an additional one pore volume of Shewanella putrefaciens (1×10 9 CFU/ml). The CFU/ml in the effluent showed about a 0.4 log kill of this microorganism. These results underlined survival of more microorganisms following the acid wash of the slim tube and the effectiveness of using an acid to detoxify the toxic zone in the slim tube. Table 3 below summarizes results of the various tests described above.
TABLE 3
Summary of the amount of amine observed in the slim tube's
effluent and the fraction of the microorganisms killed
(log kill) during residence in the slim tube.
Total Pore volume
of fluid pumped
ppm amines
log kill after
through slim tube
in the effluent
inoculating
51
0
0
131
80.5
nd
amines flood stopped
155
51.1
9.6
210
29.5
5.3
(at least)
239
4.7
4.5
(at least)
274
OMS flooded ~1 pore volume
280
4.2
2.4
299
10% HCL flooded for 1 PV
301
0.5
0.4
PV = pore volume;
nd = not detected
Example 2
Removal of N N-Dimethyl-1-Dodecanamine from Core Sand Through their Ionization at Low pH Using Hydrochloric Acid
38 milligrams (mg) of N N-Dimethyl-1-Dodecanamine (hereafter referred to as “the amine”) was added to 10.210 gr of Pentane. This solution was added to 10.1845 gr of specific sand layers (Oa and Ob) obtained from the Schrader Bluff formation of the Milne Point Unit of the Alaskan North slope. The oil content of the sand was first removed using a mixture of methanol and toluene (50/50, volume/volume) as solvent washes. The solvent mixture was subsequently evaporated off the core sand to produce clean, dry, flowable core sand. This sand was mixed with the amine and pentane solution to produce a slurry. This slurry was thoroughly mixed and the pentane was evaporated off leaving the amine on the sand (hereafter referred to as sand/amine mixture). 100 ml of brine #2 (Table 3) was added to the sand/amine mixture to create the sand/amine/brine mixture. The initial pH of the sand/amine/brine mixture was 8.4. The concentration of the amine in the water should have been 380 ppm if all the amine were dissolved in brine #2. Analysis of a sample of sand/amine/brine mixture by GC did not reveal the presence of any amines in the test sample (i.e., the amine conc. was ˜<1 ppm). The fact that the amine was not detected underlined its strong binding to the sand particles. 0.1 ml of 1 normal (N) HCl was added to this solution, and the pH and the amine concentration was measured again. This step was repeated several times and the analyses results are shown in both Table 4 and in FIG. 3 . Complete ionization and solubilization of the amine in the water was observed at pH below ˜6.0. This is a surprising finding since the pKa of HCl is −6.2 (Langes Handbook of Chemistry, 14 th edition, page 8.14, 1992, McGraw-Hill, Inc., New York). Therefore, the concentration of the HCl required for this step to completely ionize the amine and removed it from the toxic core sand may be further reduced several orders of magnitude from the 10% concentration used in this example. The data underlines the remarkable efficiency of an acid at ionizing and removing the amine from the sand.
TABLE 3
Composition of brine #2 (gr/L of deionized water)
NaHCO 3
1.38 gr
CaCl 2 *6H 2 O
0.39 gr
MgCl 2 *6H 2 O
0.220 gr
KCl
0.090 gr
NaCl
11.60 gr
TABLE 4
Amine concentration measured in Example 2
N-N-
First
dimethyl-1-
derivative
dodeanamine
(change in
(ppm) in slim
amine/change
1N HCl
sample
tube effluent
in pH)
pH
(ml)
Amine titrate st
0.00
8.14
0.00
Amine titrate 1
46.41
63.75
7.37
0.10
Amine titrate 2
59.29
63.42
7.21
0.10
Amine titrate 3
67.97
24.34
7.03
0.10
Amine titrate 4
74.38
160.35
6.59
0.10
Amine titrate 5
212.28
412.18
6.13
0.10
Amine titrate 6
288.72
679.86
6.07
0.10
Amine titrate 7
273.47
−148.78
6.04
0.05
Amine titrate 8
275.33
119.35
5.98
0.05
Amine titrate 9
303.31
65.90
5.79
0.05
Amine titrate 10
314.21
15.17
5.39
0.05
Amine titrate 11
328.48
3.24
4.13
0.05
Amine titrate 12
321.33
11.80
3.19
0.05
Amine titrate 13
342.88
47.42
2.91
0.05
Amine titrate 14
342.67
−6.52
2.74
0.05
Amine titrate 15
340.92
79.86
2.61
0.05
Amine titrate 16
369.02
80.22
2.41
0.10
Amine titrate 17
368.19
2.25
2.27
0.10
Amine titrate 18
369.54
7.51
2.18
0.10
Amine titrate 19
369.47
0.12
2.10
0.10
Amine titrate 20
369.56
2.04
0.10
Example 3
Capacity of Core Sand to Neutrilize Acid
A. Titration of Brine #2 in the Absence of Core Sand
The intent of this experiment was to determine the capacity of the core sand described in Example 2 to neutralize the HCl intended to ionize the amine accumulated in the sand.
To set up a control test, 100 ml of brine #2 was titrated with 1 N HCl to initial pH of 8.1. An aliquot (0.1 ml) of 1N HCl was added to the brine #2 and the pH was measured. The HCl addition was repeated several times and the pH was measured after each addition. Results of these analyses are shown in both Table 5 and in FIG. 4 . The data indicated that about 2.25 milliequivalents of HCl were needed to achieve the equivalence point of about pH 4 corresponding to about 100% recovery of the carbonate present in brine #2.
TABLE 5 Titration of synthetic injection brine #2 in the absence of the amine First derivative 1N HCl sample pH of pH (ml) Addition 1 8.10 0.00 Addition 2 7.67 0.73 0.10 Addition 3 7.37 0.49 0.10 Addition 4 7.18 0.35 0.10 Addition 5 7.02 0.29 0.10 Addition 6 6.89 0.23 0.10 Addition 7 6.79 0.21 0.10 Addition 8 6.68 0.19 0.10 Addition 9 6.60 0.17 0.10 Addition 10 6.51 0.15 0.10 Addition 11 6.45 0.15 0.10 Addition 12 6.36 0.18 0.10 Addition 13 6.27 0.18 0.10 Addition 14 6.18 0.18 0.10 Addition 15 6.09 0.17 0.10 Addition 16 6.01 0.17 0.10 Addition 17 5.92 0.18 0.10 Addition 18 5.83 0.19 0.10 Addition 19 5.73 0.33 0.10 Addition 20 5.50 0.32 0.10 Addition 21 5.41 0.33 0.10 Addition 22 5.17 0.74 0.10 Addition 23 4.67 1.94 0.10 Addition 24 3.23 1.86 0.10 Addition 25 2.81 0.62 0.10 Addition 26 2.61 0.36 0.10 Addition 27 2.45 0.25 0.10 Addition 28 2.36 0.17 0.10 Addition 29 2.28 0.10
B. Titration of Brine #2 with Core Sand
100 ml of brine #2 plus 10 gr of the same core sand (brine/sand mixture) used in Example 2, was titrated with 1N HCl. The initial pH of the brine/sand mixture was 7.88. 0.1 ml aliquots of 1N HCl were added to this mixture repeatedly, and the pH was measured after each HCl addition. The results shown in both Table 6 and in FIG. 4 indicated that addition of 0.3 milliequivalents of HCl was needed to achieve the equivalence point with 10 gr of sand present. The data obtained in this experiment underlines the slight capacity of the core sand to neutralize the added HCl. Consequently a small concentration of an acid, such as HCl, ionized the amine associated with the core sand without getting neutralized by reaction with the sand.
TABLE 6
Titration of brine #2 and 10 gr of core sand
Brine contained
Used 10.103 gr
1.87 gr NaHCO 3
of core sand
2.60 ml of 1N HCL
Slope of pH
ml
Sample
at pH
(first derivative)
1N HCl
1
7.88
0.00
2
7.55
0.53
0.10
3
7.35
0.36
0.10
4
7.19
0.30
0.10
5
7.05
0.24
0.10
6
6.95
0.20
0.10
7
6.85
0.18
0.10
8
6.77
0.18
0.10
9
6.67
0.17
0.10
10
6.60
0.14
0.10
11
6.53
0.14
0.10
12
6.46
0.13
0.10
13
6.40
0.12
0.10
14
6.34
0.13
0.10
15
6.27
0.13
0.10
16
6.21
0.13
0.10
17
6.14
0.15
0.10
18
6.06
0.16
0.10
19
5.98
0.16
0.10
20
5.90
0.17
0.10
21
5.81
0.21
0.10
22
5.69
0.29
0.10
23
5.52
0.34
0.10
24
5.35
0.45
0.10
25
5.07
0.80
0.10
26
4.55
1.14
0.10
27
3.93
1.13
0.10
28
3.42
0.86
0.10
29
3.07
0.52
0.10
30
2.90
0.33
0.10
31
2.74
0.24
0.10
32
2.66
0.29
0.10
33
2.45
0.34
0.20
34
2.32
0.23
0.20
35
2.22
0.18
0.20
36
2.14
0.20
Example 4
Removal of N-N-Dimethyl-1-Dodecanamine from Core Sand Through their Ionization at Low pH Using 10% Nitric Acid
The procedure outlined in Example 2 was used to produce the sand/amine mixture except that 519 mg of the amine, 10 gr of Pentane. and 60.062 gr of sand from the Oa and Ob layers were used. 29.065 gr of this sand/amine mixture was added to 100 ml of brine #2 (Table 3) to create the sand/amine/brine mixture. The initial pH of the sand/amine/brine mixture was 8.28. The concentration of the amine in the water should have been about 2000 ppm if all the amine was dissolved in brine #2. Instead, analysis of a sample of brine #2 in contact with the sand/amine/brine mixture as described above showed that the amine concentration was ˜85 ppm, i.e., far less than what was expected. The fact that only a small amount of the amine was detected in brine #2 underlined the strong binding of the amine to the sand particles. 0.1 ml of 10 weight percent (wt %) nitric acid in water was added to this solution, and the pH and the amine concentration were measured again. This step was repeated several times and the analyses results are shown in both Table 7 and in FIG. 5 . Complete ionization and solubilization in the water of the amine was observed at a pH below ˜6.7. This is a surprising finding since the pKa of nitric acid is −1.37 (Langes Handbook of Chemistry, 14 th edition, page 8.15, 1992, McGraw-Hill, Inc., New York), the concentration of the nitric acid required for this step may be further reduced several orders of magnitude from the 10 wt % used in this experiment without any negative impact on removal of the amines from the core sand.
TABLE 7
Amine concentration measured in Example 4
ppm
N-N-dimethyl-1-
ml
sample
dodeanamine
pH
10% HNO 3
start
85
8.28
0
1
110
8.13
0.1
2
211
7.72
0.1
3
216
7.42
0.1
4
235
7.25
0.1
5
540
7.2
0.1
6
745
7.29
0.1
7
1153
7.33
0.1
8
1210
7.29
0.1
9
1327
7.18
0.1
10
1315
7.11
0.1
11
1413
6.99
0.1
12
1667
6.85
0.1
13
1897
6.73
0.1
14
1853
6.64
0.1
15
1858
6.59
0.1
16
1788
6.28
0.2
17
1822
5.8
0.2
18
1975
3.46
0.2
Example 5
Removal of N-N-Dimethyl-1-Dodecanamine from Core Sand Through its Ionization at Low pH Using 10% Acetic Acid
The same procedure outlined in Example 4 was repeated here to produce the sand/amine mixture. 30.85 grams (gr) of the sand/amine mixture was added to 100 ml of brine #2 (Table 3) to create the sand/amine/brine mixture. The initial pH of the sand/amine/brine mixture was 8.52. The concentration of the amine in the water should have been about 2000 ppm if all the amine were dissolved in brine #2. Instead, analysis of brine #2 in contact with the sand/amine/brine mixture, as described above, showed that the amine concentration was ˜67 ppm, i.e., far less than what was expected. The fact that only a small amount of the amine was detected in the brine #2 underlined the strong binding of the amine to the sand particles. 0.1 ml of 10 wt % acetic acid was added to this solution, and the pH and the amine concentration were measured again. This step was repeated several times and the analyses results are shown in both Table 8 and in FIG. 6 . Complete ionization and solubilization in the water of the amine was observed at pH below ˜6.7. This is a surprising finding since the pKa of acetic acid is 4.756 (Langes Handbook of Chemistry, 14 th edition, page 8.19, 1992, McGraw-Hill, Inc., New York). Consequently, the concentration of the acetic acid required for this step may be further reduced significantly from what was used in this example without any negative impact on removal of the amine from the core sand.
The observations described above illustrate that a weak organic acid, like acetic acid can be as effective as a strong inorganic acid, like hydrochloric acid, at ionizing and separating the amines from the toxic core sand. It can therefore be concluded that to remove the toxic zone from a subterranean site, any acid that decreases the pH of a solution below about 6.7 can be used.
TABLE 8
Amine concentration measured in Example
ppm
N-N-dimethyl-1-
ml
sample
dodeanamine
pH
10% acetic acid
start
67
8.52
0
1
63
8.01
0.1
2
107
7.41
0.1
3
215
7.4
0.1
4
497
7.37
0.1
5
512
7.23
0.1
6
969
7.12
0.1
7
1239
6.98
0.1
8
1453
6.89
0.1
9
1583
6.75
0.1
10
1579
6.56
0.1
11
1616
6.39
0.1
12
1759
6.4
0.1
13
1736
6.02
0.2
14
1718
5.4
0.2
15
1743
5.04
0.2
16
1931
4.86
0.2
17
1995
4.73
0.2
18
1913
4.61
0.2
19
1881
4.52
0.2
20
1837
4.43
0.2
21
1885
4.36
0.3 | A method to improve the effectiveness of MEOR or bioremediation processes. In this method toxic chemicals accumulated in subterranean sites adjacent to the water injection wells are either dispersed or removed prior to introduction of microbial inocula for enhanced microbial oil recovery or bioremediation of these sites. | 2 |
This application is a continuation in part of and jointly owned by the same assignee as application Ser. No. 12/168,497 filed on Jul. 7, 2008 now U.S. Pat. No. 7,779,514, which claims priority to U.S. provisional application No. 60/950,222, filed Jul. 17, 2007, which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
This invention relates to cotton fiber processing and more particularly to an apparatus and method of separating foreign matter from fibrous cotton that has been ginned from the seed. About 60 years ago cotton “lint Cleaners” were introduced into cotton gins in the United States to overcome the dramatic increase of extraneous matter brought to the gins in the seed cotton harvested by the newly introduced mechanical cotton harvesters as compared to the previously customary hand picked (harvested) cotton. These “Saw-type” lint cleaners did indeed greatly improve the appearance of the lint by removing much “trash”, but also by aggressively “combing” the tufts of fibers to diffuse them and hide the remaining fine trash particles. The most successful of these “Saw Type” lint cleaners contained a “Feed Roller” working against a concave “Feed Plate” to compact the lint batt and firmly hold it about 7 mm from the sharp tips of the fine teeth on the lint cleaner cleaning cylinder that plucked the fibers from the batt. These lint cleaners were commercially very successful because they made the lint appear to the naked eye to meet the higher grades in the classing sample standard grade boxes which were the primary determinant of the lint value along with the manually determined “staple length” which also “pulled” somewhat longer by the manual grading or classing systems of the day. Soon two and even three stages of these aggressive lint cleaners were used in series benefitting the farmers, but the results at the textile spinning mills proved disappointing.
The inadequacy of the manual-visual method of classing lint cotton became apparent, and innovative researchers introduced various cotton quality test instruments that measured spinning qualities that were only vaguely sensed by manual methods, if detected at all. Several of these test instruments were improved to perform fast enough to process lint samples as they were produced during the peak of the ginning season, and they were combined into a classing system referred to as “High Volume Instrumentation” (HVI). HVI systems were officially adopted for commerce in the United States and today HVI systems are being promoted for use around the world. However, there is much inertia in the long standing manual classing systems and the transition to HVI commercial use in many foreign countries may be very gradual.
As more of these accurate spinning quality tests were made using instrument testing equipment comparing the before and after lint quality through these saw type lint cleaners, it became clear that these lint cleaners were breaking many fibers and producing neps, both of which are very detrimental to yarn quality. The location within these saw type lint cleaners that caused this fiber quality damage was controversial, but it has now been shown that the major damage is caused at the point where the cotton batt is fed to the teeth of the cleaning cylinder.
Patent application Ser. No. 12/168,497 describes apparatus that reduces fiber damage by eliminating the formation of the cotton tufts into a batt, but rather, individually applies the tufts of cotton as they come from the gin stand in an air stream directly onto the teeth of the lint cleaner cleaning cylinder teeth without mechanically restraining the tufts. This patent application is for use with lint cleaners that have short, densely spaced teeth on a solid cylinder which currently are universally used in the U.S. saw gins on upland cotton.
Roller ginning in the United States has been almost entirely confined to ginning pima cotton which is more valuable than upland cottons because of its extra long, fine fibers that warrant the slow, more expensive roller ginning process that also breaks fewer fibers than saw ginning. However, the roller ginning process has recently been made much faster until roller ginning speed (Capacity) is now nearing saw ginning capacity per unit width of ginning machine. High speed roller ginning is now being introduced to the ginning of some upland cottons in response to monetary incentives for roller ginned lint. Roller ginned lint is classed on a different system from saw ginned lint. The roller ginned lint classing system has completely different standards for “preparation”. The roller ginned “prep” standard calls for a certain lumpy appearance caused by the roller gin that pulls off much larger tufts from the seed than saw gins. The lint cleaners used with roller gins, therefore, do not as aggressively “comb” the lint to preserve the characteristic lumpy appearance of roller ginned lint. The cleaning cylinders used on roller ginned cotton generally have less densely spaced teeth or even bars or lugs which would not provide an air seal between the cleaning cylinder and the high speed separator cylinder housing as is required in application Ser. No. 12/168,497. Furthermore, the textile industry, over many years has developed several specialized cotton cleaning cylinders, including “Kirschner” and “Buckley” beaters, which have more open designs that would allow air to be drawn through the cleaning cylinder back into the high speed separator housing if the apparatus of Ser. No. 12/168,497 were used. Moreover, the open design cleaning cylinders often are self doffing and therefore they eliminate the doffing cylinder of '497, a considerable initial and maintenance expense. The principle proven benefits of Ser. No. 12/168,497 would be lost for use with these many “open” cleaning cylinders without the added concepts of the present invention.
Other prior methods and apparatus include those such as illustrated in U.S. Pat. No. 6,088,881, incorporated herein by reference, wherein a revolving perforated drum is used to allow air flow through the drum such that a cleaning cylinder may remove cotton fiber from the perforated drum and carry it past a plurality of cleaning grid bars, thereby separating the air flow and removing foreign matter from the fibers, before the fiber is doffed from the cleaning cylinder for subsequent air flow to downstream processing.
However, the perforated revolving cylinder of the '881 apparatus, revolving at velocities to prevent agglomeration of the tufts in the air stream, develops centrifugal forces that cause the fine trash and very short fibers that penetrate the perforations to accumulate on the interior surfaces of the perforated cylinder. These accumulations require the use of compressed air blasts to cause them to move axially out the open ends of the cylinder. While the compressed air blasts provide a solution to this problem of accumulations, the maintenance and cost of the compressed air system detracts from the otherwise excellent performance of the apparatus per the '881 patent.
The quality preserving actions of the methods and apparatus shown in U.S. Pat. No. 6,088,881 and application Ser. No. 12/168,497 would be beneficial for use with all types of lint cleaning cylinders, including those used with roller gins. The improvement described herein provides the solution to combining the benefits of these concepts with cleaning cylinders of most all designs.
BRIEF DESCRIPTION OF THE DRAWINGS
An apparatus embodying features of the invention is depicted in the accompanying drawing wherein:
FIG. 1 is a sectional view of the apparatus disclosed in the copending patent application Ser. No. 12/168,497;
FIG. 2 is a sectional side elevational view of an embodiment of an apparatus of the present apparatus;
FIG. 3 is a partial sectional side elevational view of another embodiment of the transfer wheel of the present apparatus.
BRIEF SUMMARY OF THE INVENTION
It is an object of the present invention to provide an improved method and apparatus for separating foreign matter from tufts of fibrous cotton. A further object of the invention is to allow the high speed separation and cleaning of upland cotton using open cleaning apparatus and a combination air seal with fiber transfer roller.
DETAILED DESCRIPTION OF THE INVENTION
As shown in FIG. 1. patent application Ser. No. 12/168,497 depends upon the short, dense teeth of the standard cleaning cylinders used in upland cotton gin lint cleaners to seal against the air partial vacuum in the housing surrounding the “high speed air separator cylinder”. This vacuum is required to induce an air stream to convey the tufts of lint to the lint cleaner. FIG. 1 taken from patent application '497 illustrates the housing around the sub atmospheric air stream entering at C and exiting at E. It also shows the air seal formed between the short, dense teeth at “ 13 ” and close fitting plate “ 27 ” preventing atmospheric pressure air from the trash removing grid area “ 23 ” being drawn into the incoming air stream C. Plate 28 also fits closely to the tips of the cleaning cylinder teeth to prevent air, coming in at D, from being drawn into the housing around the high speed air separator cylinder.
An improved apparatus and method according to the present invention is illustrated in FIG. 2 , wherein fiber tufts comingled with foreign matter are pneumatically carried by a conveying air stream C into the apparatus via an air duct 11 as is well known in the art. FIG. 2 is a cross sectional illustration of a preferred embodiment containing most of the features of the present invention. Fiber tufts, commingled with foreign matter, are conveyed into the entry duct 11 of the apparatus by a high speed air stream preferably under sub atmospheric air pressure. Entry duct 11 converges arcuately toward the periphery of high speed air separator cylinder 17 that is pervious to both inward and outward flow of fiber, foreign matter and air. However, the arcuate convergence of duct 11 combined with the high speed arcuate change of direction develops centrifugal forces urging the fiber and foreign matter to move toward the converging surface 14 of duct 11 . Approximately diametrically opposite the point on the separator cylinder where the duct 11 converges against the periphery of the air separator cylinder 17 is a stationary arcuate section of perforated screen 16 closely following the arc of the periphery of separator cylinder 17 . The perforated screen 16 is pervious to air flow there through, but impervious to desirable fiber. Any fiber that collects on the screen is immediately swept away from the screen by a plurality of circumferentially spaced outer surfaces 18 that are spaced apart circumferentially to allow the conveying air and entrained dust and fine foreign matter particles to pass through the screen 16 and exit the apparatus via an air discharge duct 15 at Q. As outer surfaces 18 rotate across perforated surface 16 the surfaces 18 substantially sweep away any accumulations of matter on the stationary separator surface 16 and return any desirable fiber back to the conveying air stream proximal terminal portion 14 of duct 11 . The rotation of revolving outer surfaces 18 is such that the commingled fiber and foreign matter are exposed to the surface 32 of air seal and fiber transfer cylinder 31 while the revolving outer surfaces 18 are rotating toward stationary semi cylindrical surface 16 .
Up to this point the present invention follows the teachings of patent application Ser. No. 12/168,497 and the preferred embodiment of the present invention likewise follows FIG. 1 of patent application Ser. No. 12/168,497. But from this point on the preferred embodiment of the present invention deviates from patent application Ser. No. 12/168,497 in that it calls for the addition of the air seal and fiber transfer cylinder 31 between the air separator cylinder 17 and the cleaning cylinder 12 as shown in FIG. 2 . As will be understood from the prior art, the rotation of cleaning cylinder 12 carries the tufts past a stripping bar and plurality of cleaning grid bars 23 disposed to separate a major portion of foreign matter from the cotton tufts on the cleaning cylinder 12 , which foreign matter may be disposed via a trash conveyor system for subsequent collection and baling. As noted above, roller ginning is generally used for the higher quality cottons and the lint cleaning machinery often uses longer, more widely spaced pin or lug type cylinders which would not prevent air flow back into the high speed separator section that is under sub atmospheric air pressure.
Air seal and fiber transfer cylinder 31 is needed for use with such a cleaning cylinder 12 that has longer, less dense teeth or lugs that would allow air to be pulled back from the trash removing grid section into the sub atmosphere air pressure housing around the high speed air separator cylinder 17 . In the present apparatus, as shown in FIG. 2 , cylinders 17 , 31 , and 12 , all revolve counter clockwise and preferably successively at increasing surface speeds. Air seal and fiber transfer cylinder 31 primarily acts as what is generally known as a “vacuum wheel”. To make this air seal, air seal and fiber transfer cylinder 31 must fit tightly against arcuate walls 37 and 36 both on the fiber carrying side and the return side of the cylinder 31 and it must be constructed to prevent air from passing through the air pressure differential across the cylinder at all times in its rotation. Also this cylinder 31 must be capable of carrying the fibers around the arcuate fiber transfer side, preferably while holding the fiber tufts firmly in place as they enter the pinch point between this cylinder and the arcuate wall 37 on the fiber carrying side and hold the tufts until they are released to the tip of a streamer plate 38 at the end of the arcuate wall from which the fibers are pulled by the teeth of cleaning cylinder 12 . Thus, in one embodiment, the surface 32 of air seal and transfer cylinder 31 is of a dense brush type consistency that will engage fibers and present a dense but flexible seal in the interstice between the cylinder 31 and the walls 36 and 37 . Such a brush like surface would preferentially be composed of bristles spaced less than about 6 millimeters apart over the surface of the transfer cylinder.
The surface of cylinder 31 should preferably be radially flexible and continuous to maintain an air seal at all times both on the lower, fiber exit side and upper return side of cylinder 31 running against stationary arcuate sealing surfaces 36 and 37 that join to the housing around separator cylinder 17 . As noted preferred outer surface for cylinder 31 is composed of continuous, dense brush bristles that entrap the fiber tufts against arcuate surface 36 and an adjustable streamer plate 38 which has an acute angle fiber delivery tip to uniformly “payout” the fiber tufts to the teeth of the faster moving surface of cleaning cylinder 12 . That is to say, streamer plate 38 converges to a tip or edge at the interstice of cylinders 31 and 12 with the converging sides being substantially tangent to the adjacent cylinders. Streamer plate is mounted such that it can be mechanically adjusted as is well known in the industry relative to the transfer cylinder 31 and the cleaning cylinder 12 , such that fiber tufts being carried past sealing surface 36 is exposed at the tip or edge of streamer plate 38 to the teeth 13 of cleaner cylinder 12 , such that the fibers may be removed from transfer cylinder 31 for processing by cleaning cylinder 12 . By way of example, streamer plate 38 may be adjusted by appropriate shims or by incorporating an adjustment slot and selectively tightened bolts to allow the plate to vary in inclination and projection.
It should also be noted that cylinder 31 may be in the form of an air wheel having a solid cylindrical core 41 and a plurality of angularly spaced radially extending flights 42 or brushes which resiliently engage walls 36 and 37 as shown in FIG. 3 . The flights 42 would be angularly spaced at distances less than the arc defined by wall 36 or 37 such that at least one flight 42 would be in sealing engagement with wall 36 and another in sealing engagement with wall 37 at all times, thereby preventing the flow of air past cylinder 31 . Flights 42 would be sufficiently resilient to carry the fiber tufts past wall 36 to where the fibers would be engaged by cleaning cylinder 12 . The flights 42 may be brushes, belts or other strip like material.
As will also appreciated, a rotating doffing cylinder or brush 24 can remove the cleaned tufts from the teeth 13 of cleaning cylinder 12 and deliver the cleaned fibers to duct 26 . FIG. 2 also shows a form of air flow doffing without a doffing cylinder often used with the more open cleaning cylinders. As may be seen the doffing airstream through inlet duct 41 and outlet duct 42 moves in conjunction with the rotating teeth or lugs of cylinder 12 such that fibers are readily entrained in the airflow. The present invention makes air doffing without a doffing cylinder usable with the proven advantages of the high speed separator taught in application Ser. No. 12/168,497.
While the forgoing specification describes only a few embodiments of the present invention, the invention is not so limited and is intended to encompass the full scope of the claims appended hereto. | An apparatus for cleaning foreign matter from separated tufts of fiber uses a transfer cylinder intermediate a revolving open reel type structure mounted within a porous housing to separate a conveying air stream from tufts of fiber conveyed thereby and a toothed cleaning cylinder to separate air flow through said revolving reel from said cleaning cylinder such that air is not drawn through said cleaning cylinder into said porous housing. | 3 |
[0001] The present invention claims priority on U.S. Provisional Patent Application Ser. No. 61/667,136 filed Jul. 2, 2012, which is incorporated herein.
[0002] The invention relates generally to medical devices, and particularly to a medical device that is at least partially formed of a novel molybdenum and rhenium metal alloy, and more particularly to dental implant, implant or prosthetic device that is at least partially formed of a novel molybdenum and rhenium metal.
SUMMARY OF THE INVENTION
[0003] The present invention is generally directed to a medical device that is at least partially made of a novel metal alloy having improved properties as compared to past medical devices. The novel metal alloy used to at least partially form the medical device improves one or more properties (e.g., strength, durability, hardness, biostability, bendability, coefficient of friction, radial strength, flexibility, tensile strength, tensile elongation, longitudinal lengthening, stress-strain properties, improved recoil properties, radiopacity, heat sensitivity, biocompatibility, etc.) of such medical device. These one or more improved physical properties of the novel metal alloy can be achieved in the medical device without having to increase the bulk, volume and/or weight of the medical device, and in some instances these improved physical properties can be obtained even when the volume, bulk and/or weight of the medical device is reduced as compared to medical devices that are at least partially formed from traditional stainless steel or cobalt and chromium alloy materials. The novel metal alloy that is used to at least partially form the medical device can thus 1) increase the radiopacity of the medical device, 2) increase the radial strength of the medical device, 3) increase the yield strength and/or ultimate tensile strength of the medical device, 4) improve the stress-strain properties of the medical device, 5) improve the crimping and/or expansion properties of the medical device, 6) improve the bendability and/or flexibility of the medical device, 7) improve the strength and/or durability of the medical device, 8) increase the hardness of the medical device, 9) improve the longitudinal lengthening properties of the medical device, 10) improve the recoil properties of the medical device, 11) improve the friction coefficient of the medical device, 12) improve the heat sensitivity properties of the medical device, 13) improve the biostability and/or biocompatibility properties of the medical device, and/or 14) enable smaller, thinner and/or lighter weight medical devices to be made. The medical device generally includes one or more materials that impart the desired properties to the medical device so as to withstand the manufacturing processes that are needed to produce the medical device. These manufacturing processes can include, but are not limited to, laser cutting, etching, crimping, annealing, drawing, pilgering, electroplating, electro-polishing, chemical polishing, cleaning, pickling, ion beam deposition or implantation, sputter coating, vacuum deposition, etc.
[0004] In one non-limiting aspect of the present invention, a medical device that can include the novel metal alloy is a dental implant, a spinal implant, a prosthetic device to repair or replace a bone (e.g., acromion, atlas, axis, calcaneus, carpus, clavicle, coccyx, epicondyle, epitrochlea, femur, fibula, frontal bone, greater trochanter, humerus, ilium, ischium, mandible, maxilla, metacarpus, metatarsus, occipital bone, olecranon, parietal bone, patella, phalanx, radius, ribs, sacrum, scapula, sternum, talus, tarsus, temporal bone, tibia, ulna, zygomatic bone, etc.), a nail, screw, post, or other structural assembly that is used in a body to support a structure, mount a structure and/or repair a structure in a body such as, but not limited to, a human body. In one non-limiting application, the medical device is a dental implant dental filling, dental tooth cap, dental bridge, braces for teeth, dental teeth cleaning equipment, and/or any other medical device used in the dental or orthodontist field.
[0005] In another and/or alternative non-limiting aspect of the present invention, the medical device is generally designed to include at least about 25 weight percent of the novel metal alloy; however, this is not required. In one non-limiting embodiment of the invention, the medical device includes at least about 40 weight percent of the novel metal alloy. In another and/or alternative non-limiting embodiment of the invention, the medical device includes at least about 50 weight percent of the novel metal alloy. In still another and/or alternative non-limiting embodiment of the invention, the medical device includes at least about 60 weight percent of the novel metal alloy. In yet another and/or alternative non-limiting embodiment of the invention, the medical device includes at least about 70 weight percent of the novel metal alloy. In still yet another and/or alternative non-limiting embodiment of the invention, the medical device includes at least about 85 weight percent of the novel metal alloy. In a further and/or alternative non-limiting embodiment of the invention, the medical device includes at least about 90 weight percent of the novel metal alloy. In still a further and/or alternative non-limiting embodiment of the invention, the medical device includes at least about 95 weight percent of the novel metal alloy. In yet a further and/or alternative non-limiting embodiment of the invention, the medical device includes about 100 weight percent of the novel metal alloy.
[0006] In still another and/or alternative non-limiting aspect of the present invention, the novel metal alloy that is used to form all or part of the medical device 1) is not clad, metal sprayed, plated and/or formed (e.g., cold worked, hot worked, etc.) onto another metal, or 2) does not have another metal or metal alloy metal sprayed, plated, clad and/or formed onto the novel metal alloy. It will be appreciated that in some applications, the novel metal alloy of the present invention may be clad, metal sprayed, plated and/or formed onto another metal, or another metal or metal alloy may be plated, metal sprayed, clad and/or formed onto the novel metal alloy when forming all or a portion of a medical device.
[0007] In yet another and/or alternative non-limiting aspect of the present invention, the novel metal alloy that is used to form all or a portion of the medical device includes rhenium and molybdenum. The novel alloy can include one or more other metals such as, but not limited to, calcium, chromium, cobalt, copper, gold, iron, lead, magnesium, nickel, niobium, platinum, rare earth metals, silver, tantalum, titanium, tungsten, yttrium, zinc, zirconium, and/or alloys thereof.
[0008] In still another and/or alternative non-limiting aspect of the present invention, the novel metal alloy that is used to form all or a portion of the medical device is a novel metal alloy that includes at least about 90 weight percent molybdenum and rhenium. In one non-limiting composition, the content of molybdenum and rhenium in the novel metal alloy is at least about 95 weight percent. In another and/or alternative non-limiting composition, the content of molybdenum and rhenium in the novel metal alloy is at least about 97 weight percent. In still another and/or alternative non-limiting composition, the content of molybdenum and rhenium in the novel metal alloy is at least about 98 weight percent. In yet another and/or alternative non-limiting composition, the content of molybdenum and rhenium in the novel metal alloy is at least about 99 weight percent. In still yet another and/or alternative non-limiting composition, the content of molybdenum and rhenium in the novel metal alloy is at least about 99.5 weight percent. In a further one non-limiting composition, the content of molybdenum and rhenium in the novel metal alloy is at least about 99.9 weight percent. In still a further and/or alternative non-limiting composition, the content of molybdenum and rhenium in the novel metal alloy is at least about 99.95 weight percent. In yet a further and/or alternative non-limiting composition, the content of molybdenum and rhenium in the novel metal alloy is at least about 99.99 weight percent. As can be appreciated, other weight percentages of the rhenium and molybdenum content of the novel metal alloy can be used. In one non-limiting composition, the purity level of the novel metal alloy is such so as to produce a solid solution of the novel metal alloy. A solid solution or homogeneous solution is defined as a metal alloy that includes two or more primary metals and the combined weight percent of the primary metals is at least about 95 weight percent, typically at least about 99 weight percent, more typically at least about 99.5 weight percent, even more typically at least about 99.8 weight percent, and still even more typically at least about 99.9 weight percent. A primary metal is a metal component of the metal alloy that is not a metal impurity. A solid solution of a novel metal alloy that includes rhenium and molybdenum as the primary metals is an alloy that includes at least about 95-99 weight percent rhenium and molybdenum. It is believed that a purity level of less than 95 weight percent molybdenum and rhenium adversely affects one or more physical properties of the metal alloy that are useful or desired in forming and/or using a medical device. In one embodiment of the invention, the rhenium content of the novel metal alloy in accordance with the present invention is at last about 35 weight percent. In one non-limiting composition, the rhenium content of the novel metal alloy is at least about 40 weight percent. In another and/or alternative non-limiting composition, the rhenium content of the novel metal alloy is about 45 weight percent. In still another and/or alternative non-limiting composition, the rhenium content of the novel metal alloy is about 45-50 weight percent. In yet another and/or alternative non-limiting composition, the rhenium content of the novel metal alloy is about 47-48 weight percent. In still yet another and/or alternative non-limiting composition, the rhenium content of the novel metal alloy is about 47.6-49.5 weight percent. As can be appreciated, other weight percentages of the rhenium content of the novel metal alloy can be used. In another and/or alternative embodiment of the invention, the molybdenum content of the novel metal alloy in accordance with the present invention is at least about 35 weight percent. In one non-limiting composition, the molybdenum content of the novel metal alloy is at least about 40 weight percent. In another non-limiting composition, the molybdenum content of the novel metal alloy is at least about 45 weight percent. In still another and/or alternative non-limiting composition, the molybdenum content of the novel metal alloy is at least about 50 weight percent. In yet another and/or alternative non-limiting composition, the molybdenum content of the novel metal alloy is about 50-60 percent. In still yet another and/or alternative non-limiting composition, the molybdenum content of the novel metal alloy is about 50-56 weight percent. In another and/or alternative non-limiting composition, the molybdenum content of the novel metal alloy is about 35-90 weight percent, and the rhenium content of the novel metal alloy is about 35-90 weight percent. In still another and/or alternative non-limiting composition, the molybdenum content of the novel metal alloy is about 35-90 weight percent, and the rhenium content of the novel metal alloy is about 35-90 weight percent and the combined rhenium content and molybdenum content of the novel metal alloy is about 50-100 weight percent. As can be appreciated, other weight percentages of the molybdenum content of the novel metal alloy can be used.
[0009] In still yet another and/or alternative non-limiting aspect of the present invention, the novel metal alloy that is used to form all or a portion of the medical device is a novel metal alloy that includes at least about 90 weight percent molybdenum and rhenium, and at least one additional metal which includes titanium, yttrium, and/or zirconium. The addition of controlled amounts of titanium, yttrium, and/or zirconium to the molybdenum and rhenium alloy has been found to form a metal alloy that has improved physical properties over a metal alloy that principally includes molybdenum and rhenium. For instance, the addition of controlled amounts of titanium, yttrium, and/or zirconium to the molybdenum and rhenium alloy can result in 1) an increase in yield strength of the alloy as compared to a metal alloy that principally includes molybdenum and rhenium, 2) an increase in tensile elongation of the alloy as compared to a metal alloy that principally includes molybdenum and rhenium, 3) an increase in ductility of the alloy as compared to a metal alloy that principally includes molybdenum and rhenium, 4) a reduction in grain size of the alloy as compared to a metal alloy that principally includes molybdenum and rhenium, 5) a reduction in the amount of free carbon, oxygen and/or nitrogen in the alloy as compared to a metal alloy that principally includes molybdenum and rhenium, and/or 6) a reduction in the tendency of the alloy to form micro-cracks during the forming of the alloy into a medical device as compared to the forming of a medical device from a metal alloy that principally includes molybdenum and rhenium. In one non-limiting composition, the content of molybdenum and rhenium and the at least one additional metal in the novel metal alloy is at least about 90 weight percent. In another and/or alternative non-limiting composition, the content of molybdenum and rhenium and the at least one additional metal in the novel metal alloy is at least about 95 weight percent. In still another and/or alternative non-limiting composition, the content of molybdenum and rhenium and the at least one additional metal in the novel metal alloy is at least about 98 weight percent. In yet another and/or alternative non-limiting composition, the content of molybdenum and rhenium and the at least one additional metal in the novel metal alloy is at least about 99 weight percent. In still yet another and/or alternative non-limiting composition, the content of molybdenum and rhenium and the at least one additional metal in the novel metal alloy is at least about 99.5 weight percent. In a further one non-limiting composition, the content of molybdenum and rhenium and the at least one additional metal in the novel metal alloy is at least about 99.9 weight percent. In still a further and/or alternative non-limiting composition, the content of molybdenum and rhenium and the at least one additional metal in the novel metal alloy is at least about 99.95 weight percent. In yet a further and/or alternative non-limiting composition, the content of molybdenum and rhenium and the at least one additional metal in the novel metal alloy is at least about 99.99 weight percent. As can be appreciated, other weight percentages of the content of molybdenum and rhenium and the at least one additional metal in the novel metal alloy can be used. In one non-limiting composition, the purity level of the novel metal alloy is such so as to produce a solid solution of a rhenium and molybdenum and the at least one additional metal. A solid solution of a novel metal alloy that includes rhenium and molybdenum and the at least one additional metal of titanium, yttrium and/or zirconium as the primary metals is an alloy that includes at least about 95-99 weight percent rhenium and molybdenum and the at least one additional metal. It is believed that a purity level of less than 95 weight percent molybdenum and rhenium and the at least one additional metal adversely affects one or more physical properties of the metal alloy that are useful or desired in forming and/or using a medical device. In one embodiment of the invention, the rhenium content of the novel metal alloy in accordance with the present invention is at least about 40 weight percent. In one non-limiting composition, the rhenium content of the novel metal alloy is at least about 45 weight percent. In still another and/or alternative non-limiting composition, the rhenium content of the novel metal alloy is about 45-50 weight percent. In yet another and/or alternative non-limiting composition, the rhenium content of the novel metal alloy is about 47-48 weight percent. As can be appreciated, other weight percentages of the rhenium content of the novel metal alloy can be used. In another and/or alternative embodiment of the invention, the molybdenum content of the novel metal alloy is at least about 40 weight percent. In one non-limiting composition, the molybdenum content of the novel metal alloy is at least about 45 weight percent. In another and/or alternative non-limiting composition, the molybdenum content of the novel metal alloy is at least about 50 weight percent. In still another and/or alternative non-limiting composition, the molybdenum content of the novel metal alloy is about 50-60 percent. In yet another and/or alternative non-limiting composition, the molybdenum content of the novel metal alloy is about 50-56 weight percent. As can be appreciated, other weight percentages of the molybdenum content of the novel metal alloy can be used. The combined content of titanium, yttrium and zirconium in the novel metal alloy is less than about 5 weight percent, typically no more than about 1 weight percent, and more typically no more than about 0.5 weight percent. A higher weight percent content of titanium, yttrium and/or zirconium in the novel metal alloy can begin to adversely affect the brittleness of the novel metal alloy. When titanium is included in the novel metal alloy, the titanium content is typically less than about 1 weight percent, more typically less than about 0.6 weight percent, even more typically about 0.05-0.5 weight percent, still even more typically about 0.1-0.5 weight percent. As can be appreciated, other weight percentages of the titanium content of the novel metal alloy can be used. When zirconium is included in the novel metal alloy, the zirconium content is typically less than about 0.5 weight percent, more typically less than about 0.3 weight percent, even more typically about 0.01-0.25 weight percent, still even more typically about 0.05-0.25 weight percent. As can be appreciated, other weight percentages of the zirconium content of the novel metal alloy can be used. When titanium and zirconium are included in the novel metal alloy, the weight ratio of titanium to zirconium is about 1-10:1, typically about 1.5-5:1, and more typically about 1.75-2.5:1. When yttrium is included in the novel metal alloy, the yttrium content is typically less than about 0.3 weight percent, more typically less than about 0.2 weight percent, and even more typically about 0.01-0.1 weight percent. As can be appreciated, other weight percentages of the yttrium content of the novel metal alloy can be used. The inclusion of titanium, yttrium and/or zirconium in the novel metal alloy is believed to result in a reduction of oxygen trapped in the solid solution of the novel metal alloy. The reduction of trapped oxygen enables the formation of a smaller grain size in the novel metal alloy and/or an increase in the ductility of the novel metal alloy. The reduction of trapped oxygen in the novel metal alloy can also increase the yield strength of the novel metal alloy as compared to alloys of only molybdenum and rhenium (i.e., 2-10% increase). The inclusion of titanium, yttrium and/or zirconium in the novel metal alloy is also believed to cause a reduction in the trapped free carbon in the novel metal alloy. The inclusion of titanium, yttrium and/or zirconium in the novel metal alloy is believed to form carbides with the free carbon in the novel metal alloy. This carbide formation is also believed to improve the ductility of the novel metal alloy and to also reduce the incidence of cracking during the forming of the metal alloy into a medical device (e.g., medical device, etc.). As such, the novel metal alloy exhibits increased tensile elongation as compared to alloys of only molybdenum and rhenium (i.e., 1-8% increase). The inclusion of titanium, yttrium and/or zirconium in the novel metal alloy is also believed to cause a reduction in the trapped free nitrogen in the novel metal alloy. The inclusion of titanium, yttrium and/or zirconium in the novel metal alloy is believed to form carbo-nitrides with the free carbon and free nitrogen in the novel metal alloy. This carbo-nitride formation is also believed to improve the ductility of the novel metal alloy and to also reduce the incidence of cracking during the forming of the metal alloy into a medical device (e.g., medical device, etc.). As such, the novel metal alloy exhibits increased tensile elongation as compared to alloys of only molybdenum and rhenium (i.e., 1-8% increase). The reduction in the amount of free carbon, oxygen and/or nitrogen in the novel metal alloy is also believed to increase the density of the novel metal alloy (i.e., 1-5% increase). The formation of carbides, carbo-nitrides, and/or oxides in the novel metal alloy results in the formation of dispersed second phase particles in the novel metal alloy, thereby facilitating in the formation of small grain sizes in the metal alloy.
[0010] In still another and/or alternative non-limiting aspect of the present invention, the novel metal alloy includes less than about 5 weight percent other metals and/or impurities. A high purity level of the novel metal alloy results in the formation of a more homogeneous alloy, which in turn results in a more uniform density throughout the novel metal alloy, and also results in the desired yield and ultimate tensile strengths of the novel metal alloy. The density of the novel metal alloy is generally at least about 12 gm/cc, and typically at least about 13-13.5 gm/cc. This substantially uniform high density of the novel metal alloy significantly improves the radiopacity of the novel metal alloy. In one non-limiting composition, the novel metal alloy includes less than about 1 weight percent other metals and/or impurities. In another and/or alternative non-limiting composition, the novel metal alloy includes less than about 0.5 weight percent other metals and/or impurities. In still another and/or alternative non-limiting composition, the novel metal alloy includes less than about 0.4 weight percent other metals and/or impurities. In yet another and/or alternative non-limiting composition, the novel metal alloy includes less than about 0.2 weight percent other metals and/or impurities. In still yet another and/or alternative non-limiting composition, the novel metal alloy includes less than about 0.1 weight percent other metals and/or impurities. In a further and/or alternative non-limiting composition, the novel metal alloy includes less than about 0.05 weight percent other metals and/or impurities. In still a further and/or alternative non-limiting composition, the novel metal alloy includes less than about 0.02 weight percent other metals and/or impurities. In yet a further and/or alternative non-limiting composition, the novel metal alloy includes less than about 0.01 weight percent other metals and/or impurities. As can be appreciated, other weight percentages of the amount of other metals and/or impurities in the novel metal alloy can exist.
[0011] In yet another and/or alternative non-limiting aspect of the present invention, the metal alloy includes a certain amount of carbon and oxygen. These two elements have been found to affect the forming properties and brittleness of the metal alloy. The controlled atomic ratio of carbon and oxygen in the metal alloy also can be used to minimize the tendency of the metal alloy to form micro-cracks during the forming of the novel alloy into a medical device, and/or during the use and/or expansion of the medical device in various regions of a body. The control of the atomic ratio of carbon to oxygen in the metal alloy allows for the redistribution of oxygen in the metal alloy so as to minimize the tendency of micro-cracking in the metal alloy during the forming of the metal alloy into a medical device, and/or during the use and/or expansion of the medical device in various regions of a body. The atomic ratio of carbon to oxygen in the alloy is believed to be important to minimize the tendency of micro-cracking in the metal alloy, improve the degree of elongation of the metal alloy, both of which can affect one or more physical properties of the metal alloy that are useful or desired in forming and/or using the medical device. The carbon to oxygen atomic ratio can be as low as about 0.2:1. In one non-limiting formulation, the carbon to oxygen atomic ratio in the metal alloy is generally at least about 0.4:1 (i.e., weight ratio of about 0.3:1). In another non-limiting formulation, the carbon to oxygen atomic ratio in the metal alloy is generally at least about 0.5:1 (i.e., weight ratio of about 0.375:1). In still another non-limiting formulation, the carbon to oxygen atomic ratio in the metal alloy is generally at least about 1:1 (i.e., weight ratio of about 0.75:1). In yet another non-limiting formulation, the carbon to oxygen atomic ratio in the metal alloy is generally at least about 2:1 (i.e., weight ratio of about 1.5:1). In still yet another non-limiting formulation, the carbon to oxygen atomic ratio in the metal alloy is generally at least about 2.5:1 (i.e., weight ratio of about 1.88:1). In still another non-limiting formulation, the carbon to oxygen atomic ratio in the metal alloy is generally at least about 3:1 (i.e., weight ratio of about 2.25:1). In yet another non-limiting formulation, the carbon to oxygen atomic ratio in the metal alloy is generally at least about 4:1 (i.e., weight ratio of about 3:1). In still yet another non-limiting formulation, the carbon to oxygen atomic ratio in the metal alloy is generally at least about 5:1 (i.e., weight ratio of about 3.75:1). In still another non-limiting formulation, the carbon to oxygen atomic ratio in the metal alloy is generally about 2.5-50:1 (i.e., weight ratio of about 1.88-37.54:1). In a further non-limiting formulation, the carbon to oxygen atomic ratio in the metal alloy is generally about 2.5-20:1 (i.e., weight ratio of about 1.88-15:1). In a further non-limiting formulation, the carbon to oxygen atomic ratio in the metal alloy is generally about 2.5-13.3:1 (i.e., weight ratio of about 1.88-10:1). In still a further non-limiting formulation, the carbon to oxygen atomic ratio in the metal alloy is generally about 2.5-10:1 (i.e., weight ratio of about 1.88-7.5:1). In yet a further non-limiting formulation, the carbon to oxygen atomic ratio in the metal alloy is generally about 2.5-5:1 (i.e., weight ratio of about 1.88-3.75:1). As can be appreciated, other atomic ratios of the carbon to oxygen in the metal alloy can be used. The carbon to oxygen ratio can be adjusted by intentionally adding carbon to the metal alloy until the desired carbon to oxygen ratio is obtained. Typically the carbon content of the metal alloy is less than about 0.2 weight percent. Carbon contents that are too large can adversely affect the physical properties of the metal alloy. In one non-limiting formulation, the carbon content of the metal alloy is less than about 0.1 weight percent of the metal alloy. In another non-limiting formulation, the carbon content of the metal alloy is less than about 0.05 weight percent of the metal alloy. In still another non-limiting formulation, the carbon content of the metal alloy is less than about 0.04 weight percent of the metal alloy. When carbon is not intentionally added to the metal alloy, the metal alloy can include up to about 150 ppm carbon, typically up to about 100 ppm carbon, and more typically less than about 50 ppm carbon. The oxygen content of the metal alloy can vary depending on the processing parameters used to form the metal alloy. Generally, the oxygen content is to be maintained at very low levels. In one non-limiting formulation, the oxygen content is less than about 0.1 weight percent of the metal alloy. In another non-limiting formulation, the oxygen content is less than about 0.05 weight percent of the metal alloy. In still another non-limiting formulation, the oxygen content is less than about 0.04 weight percent of the metal alloy. In yet another non-limiting formulation, the oxygen content is less than about 0.03 weight percent of the metal alloy. In still yet another non-limiting formulation, the metal alloy includes up to about 100 ppm oxygen. In a further non-limiting formulation, the metal alloy includes up to about 75 ppm oxygen. In still a further non-limiting formulation, the metal alloy includes up to about 50 ppm oxygen. In yet a further non-limiting formulation, the metal alloy includes up to about 30 ppm oxygen. In still yet a further non-limiting formulation, the metal alloy includes less than about 20 ppm oxygen. In yet a further non-limiting formulation, the metal alloy includes less than about 10 ppm oxygen. As can be appreciated, other amounts of carbon and/or oxygen in the metal alloy can exist. It is believed that the metal alloy will have a very low tendency to form micro-cracks during the formation of the medical device (e.g., medical device, etc.) and after the medical device has been inserted into a patient by closely controlling the carbon to oxygen ration when the oxygen content exceed a certain amount in the metal alloy. In one non-limiting arrangement, the carbon to oxygen atomic ratio in the metal alloy is at least about 2.5:1 when the oxygen content is greater than about 100 ppm in the metal alloy.
[0012] In still yet another and/or alternative non-limiting aspect of the present invention, the metal alloy includes a controlled amount of nitrogen. Large amounts of nitrogen in the metal alloy can adversely affect the ductility of the metal alloy. This can in turn adversely affect the elongation properties of the metal alloy. A too high nitrogen content in the metal alloy, can begin to cause the ductility of the metal alloy to unacceptably decrease, thus adversely affect one or more physical properties of the metal alloy that are useful or desired in forming and/or using the medical device. In one non-limiting formulation, the metal alloy includes less than about 0.001 weight percent nitrogen. In another non-limiting formulation, the metal alloy includes less than about 0.0008 weight percent nitrogen. In still another non-limiting formulation, the metal alloy includes less than about 0.0004 weight percent nitrogen. In yet another non-limiting formulation, the metal alloy includes less than about 30 ppm nitrogen. In still yet another non-limiting formulation, the metal alloy includes less than about 25 ppm nitrogen. In still another non-limiting formulation, the metal alloy includes less than about 10 ppm nitrogen. In yet another non-limiting formulation, the metal alloy includes less than about 5 ppm nitrogen. As can be appreciated, other amounts of nitrogen in the metal alloy can exist. The relationship of carbon, oxygen and nitrogen in the metal alloy is also believed to be important. It is believed that the nitrogen content should be less than the content of carbon or oxygen in the metal alloy. In one non-limiting formulation, the atomic ratio of carbon to nitrogen is at least about 2:1 (i.e., weight ratio of about 1.71:1). In another non-limiting formulation, the atomic ratio of carbon to nitrogen is at least about 3:1 (i.e., weight ratio of about 2.57:1). In still another non-limiting formulation, the atomic ratio of carbon to nitrogen is about 4-100:1 (i.e., weight ratio of about 3.43-85.7:1). In yet another non-limiting formulation, the atomic ratio of carbon to nitrogen is about 4-75:1 (i.e., weight ratio of about 3.43-64.3:1). In still another non-limiting formulation, the atomic ratio of carbon to nitrogen is about 4-50:1 (i.e., weight ratio of about 3.43-42.85:1). In yet another non-limiting formulation, the atomic ratio of carbon to nitrogen is about 4-35:1 (i.e., weight ratio of about 3.43-30:1). In still yet another non-limiting formulation, the atomic ratio of carbon to nitrogen is about 4-25:1 (i.e., weight ratio of about 3.43-21.43:1). In a further non-limiting formulation, the atomic ratio of oxygen to nitrogen is at least about 1.2:1 (i.e., weight ratio of about 1.37:1). In another non-limiting formulation, the atomic ratio of oxygen to nitrogen is at least about 2:1 (i.e., weight ratio of about 2.28:1). In still another non-limiting formulation, the atomic ratio of oxygen to nitrogen is about 3-100:1 (i.e., weight ratio of about 3.42-114.2:1). In yet another non-limiting formulation, the atomic ratio of oxygen to nitrogen is at least about 3-75:1 (i.e., weight ratio of about 3.42-85.65:1). In still yet another non-limiting formulation, the atomic ratio of oxygen to nitrogen is at least about 3-55:1 (i.e., weight ratio of about 3.42-62.81:1). In yet another non-limiting formulation, the atomic ratio of oxygen to nitrogen is at least about 3-50:1 (i.e., weight ratio of about 3.42-57.1:1).
[0013] In a further and/or alternative non-limiting aspect of the present invention, the metal alloy has several physical properties that positively affect the medical device when at least partially formed of the metal alloy. In one non-limiting embodiment of the invention, the average Vickers hardness of the metal alloy tube used to form the medical device is generally at least about 234 DHP (i.e., Rockwell A hardness of at least about 60 at 77° F., Rockwell C hardness of at least about 19 at 77° F.). In one non-limiting aspect of this embodiment, the average hardness of the metal alloy used to form the medical device is generally at least about 248 DHP (i.e., Rockwell A hardness of at least about 62 at 77° F., Rockwell C hardness of at least about 22 at 77° F.). In another and/or additional non-limiting aspect of this embodiment, the average hardness of the metal alloy used to form the medical device is generally about 248-513 DHP (i.e., Rockwell A hardness of about 62-76 at 77° F., Rockwell C hardness of about 22-50 at 77° F.). In still another and/or additional non-limiting aspect of this embodiment, the average hardness of the metal alloy used to form the medical device is generally about 272-458 DHP (i.e., Rockwell A hardness of about 64-74 at 77° F., Rockwell C hardness of about 26-46 at 77° F.). When titanium, yttrium and/or zirconium are included in an alloy of molybdenum and rhenium, the average hardness of the metal alloy is generally increased. Tungsten and tantalum alloys also generally have an average hardness of the metal alloy that is greater that is slightly greater than pure alloys of molybdenum and rhenium. In tungsten and tantalum alloys, and molybdenum and rhenium alloys that include titanium, yttrium and/or zirconium, the average hardness is generally at least about 60 (HRC) at 77° F., typically at least about 70 (HRC) at 77° F., and more typically about 80-100 (HRC) at 77° F. In another and/or alternative non-limiting embodiment of the invention, the average ultimate tensile strength of the metal alloy used to form the medical device is generally at least about 60 UTS (ksi). In non-limiting aspect of this embodiment, the average ultimate tensile strength of the metal alloy used to form the medical device is generally at least about 70 UTS (ksi), typically about 80-320 UTS (ksi), and more typically about 100-310 UTS (ksi). The average ultimate tensile strength of the metal alloy may vary somewhat when the metal alloy is in the form of a tube or a solid wire. When the metal alloy is in the form of a tube, the average ultimate tensile strength of the metal alloy tube is generally about 80-150 UTS (ksi), typically at least about 110 UTS (ksi), and more typically 110-140 UTS (ksi). When the metal alloy is in the form of a solid wire, the average ultimate tensile strength of the metal alloy wire is generally about 120-310 UTS (ksi). In still another and/or alternative non-limiting embodiment of the invention, the average yield strength of the metal alloy used to form the medical device is at least about 70 ksi. In one non-limiting aspect of this embodiment, the average yield strength of the metal alloy used to form the medical device is at least about 80 ksi, and typically about 100-140 (ksi). In yet another and/or alternative non-limiting embodiment of the invention, the average grain size of the metal alloy used to form the medical device is no greater than about 4 ASTM (e.g., ASTM 112-96). The grain size can be as small as about 14-15 ASTM can be achieved; however, the grain size is typically larger than 15 ASTM. The small grain size of the metal alloy enables the medical device to have the desired elongation and ductility properties that are useful in enabling the medical device to be formed, crimped and/or expanded. In one non-limiting aspect of this embodiment, the average grain size of the metal alloy used to form the medical device is about 5.2-10 ASTM, typically about 5.5-9 ASTM, more typically about 6-9 ASTM, still more typically about 6-9 ASTM, even more typically about 6.6-9 ASTM, and still even more typically about 7-8.5 ASTM. In still yet another and/or alternative non-limiting embodiment of the invention, the average tensile elongation of the metal alloy used to form the medical device is at least about 25%. A medical device that does not have an average tensile elongation of at least about 25% can form micro-cracks and/or break during the forming, crimping and/or expansion of the medical device. In one non-limiting aspect of this embodiment, the average tensile elongation of the metal alloy used to form the medical device is about 25-35%. The unique combination of the rhenium and molybdenum or tungsten and tantalum in the metal alloy in combination with achieving the desired purity and composition of the alloy and the desired grain size of the metal alloy results in 1) a medical device having the desired high ductility at about room temperature, 2) a medical device having the desired amount of tensile elongation, 3) a homogeneous or solid solution of a metal alloy having high radiopacity, 4) a reduction or prevention of micro-crack formation and/or breaking of the metal alloy tube when the metal alloy tube is sized and/or cut to form the medical device, 5) a reduction or prevention of micro-crack formation and/or breaking of the medical device when the medical device is crimped onto a balloon and/or other type of medical device for insertion into various regions of a body, 6) a reduction or prevention of micro-crack formation and/or breaking of the medical device when the medical device is bent and/or expanded, 7) a medical device having the desired ultimate tensile strength and yield strength, and/or 8) a medical device that exhibits less recoil when the medical device is crimped and/or expanded.
[0014] Several non-limiting examples of the metal alloy that can be made in accordance with the present invention are set forth below:
[0000]
Metal/Wt. %
Ex. 1
Ex. 2
Ex.3
C
<150 ppm
<50 ppm
<50 ppm
Mo
51-54%
52.5-55.5%
50.5-52.4%
O
<50 ppm
<10 ppm
<10 ppm
N
<20 ppm
<10 ppm
<10 ppm
Re
46-49%
44.5-47.5%
47.6-49.5%
Ex. 4
Ex. 5
Ex. 6
Ex. 7
C
≦50 ppm
≦50 ppm
≦50 ppm
≦50 ppm
Mo
51-54%
52.5-55.5%
52-56%
52.5-55%
O
≦20 ppm
≦20 ppm
≦10 ppm
≦10 ppm
N
≦20 ppm
≦20 ppm
≦10 ppm
≦10 ppm
Re
46-49%
44.5-47.5%
44-48%
45-47.5%
Ti
≦0.4%
≦0.4%
0.2-0.4%
0.3-0.4%
Y
≦0.1%
≦0.1%
0-0.08%
0.005-0.05%
Zr
≦0.2%
≦0.2%
0-0.2%
0.1-0.25%
Ex. 8
Ex. 9
Ex. 10
Ex. 11
C
≦40 ppm
≦40 ppm
≦40 ppm
≦40 ppm
Mo
50.5-53%
51.5-54%
52-55%
52.5-55%
O
≦15 ppm
≦15 ppm
≦15 ppm
≦10 ppm
N
≦10 ppm
≦10 ppm
≦10 ppm
≦10 ppm
Re
47-49.5%
46-48.5%
45-48%
45-47.5%
Ti
0.1-0.35%
0%
0%
0.1-0.3%
Y
0%
0.002-0.08%
0%
0%
Zr
0%
0%
00.1-0.2%
0.05-0.15%
Ex. 12
Ex.13
Ex.14
Ex. 15
C
≦40 ppm
≦40 ppm
<150 ppm
<150 ppm
Mo
52-55%
52.5-55.5%
50-60%
50-60%
O
≦10 ppm
≦10 ppm
≦100 ppm
≦100 ppm
N
≦10 ppm
≦10 ppm
≦40 ppm
≦40 ppm
Re
45-49%
44.5-47.5%
40-50%
40-50%
Ti
0.05-0.4%
0%
0%
≦1%
Y
0.005-0.07%
0.004-0.06%
0%
≦0.1%
Zr
0%
0.1-0.2%
0%
≦2%
Ex. 16.
Ex.17
Ex.18
Ex. 19
C
≦150 ppm
≦150 ppm
≦150 ppm
≦150 ppm
Mo
50-55%
52-55.5%
51-58%
50-56%
O
≦100 ppm
≦100 ppm
≦100 ppm
≦100 ppm
N
≦40 ppm
≦20 ppm
≦20 ppm
≦20 ppm
Re
45-50%
44.5-48%
42-49%
44-50%
Ti
0%
0%
0%
0%
Y
0%
0%
0%
0%
Zr
0%
0%
0%
0%
Ex. 20
Ex. 21
Ex. 22
C
<150 ppm
<50 ppm
<50 ppm
Mo
51-54%
52.5-55.5%
50.5-52.4%
O
<50 ppm
<10 ppm
<10 ppm
N
<20 ppm
<10 ppm
<10 ppm
Re
46-49%
44.5-47.5%
47.6-49.5%
Ti
0%
0%
0%
Y
0%
0%
0%
Zr
0%
0%
0%
Ex. 23
Ex. 24
Ex. 25
C
≦150 ppm
≦150 ppm
≦150 ppm
Mo
50-60%
50-60%
50-55%
O
≦100 ppm
≦100 ppm
≦100 ppm
N
≦40 ppm
≦40 ppm
≦40 ppm
Re
40-50%
40-50%
45-50%
Ti
≦0.5%
≦0.5%
≦0.5%
Y
≦0.1%
≦0.1%
≦0.1%
Zr
≦0.25%
≦0.25%
≦0.25%
Ex. 26
Ex. 27
Ex. 28
C
≦150 ppm
≦150 ppm
≦150 ppm
Mo
52-55.5%
51-58%
50-56%
O
≦100 ppm
≦100 ppm
≦100 ppm
N
≦20 ppm
≦20 ppm
≦20 ppm
Re
44.5-48%
42-49%
44-50%
Ti
≦0.5%
≦0.5%
≦0.5%
Y
≦0.1%
≦0.1%
≦0.1%
Zr
≦0.25%
≦0.25%
≦0.25%
Ex. 29
Ex. 30
Ex. 31
Ex. 32
C
≦50 ppm
≦50 ppm
≦50 ppm
≦50 ppm
Mo
51-54%
52.5-55.5%
52-56%
52.5-55%
O
≦20 ppm
≦20 ppm
≦10 ppm
≦10 ppm
N
≦20 ppm
≦20 ppm
≦10 ppm
≦10 ppm
Re
46-49%
44.5-47.5%
44-48%
45-47.5%
Ti
≦0.4%
≦0.4%
0.2-0.4%
0.3-0.4%
Y
≦0.1%
≦0.1%
0-0.08%
0.005-0.05%
Zr
≦0.2%
≦0.2%
0-0.2%
0.1-0.25%
Ex. 33
Ex. 34
Ex. 35
Ex. 36
C
≦40 ppm
≦40 ppm
≦40 ppm
≦40 ppm
Mo
50.5-53%
51.5-54%
52-55%
52.5-55%
O
≦15 ppm
≦15 ppm
≦15 ppm
≦10 ppm
N
≦10 ppm
≦10 ppm
≦10 ppm
≦10 ppm
Re
47-49.5%
46-48.5%
45-48%
45-47.5%
Ti
0.1-0.35%
0%
0%
0.1-0.3%
Y
0%
0.002-0.08%
0%
0%
Zr
0%
0%
0.01-0.2%
0.05-0.15%
Ex. 37
Ex. 38
C
≦40 ppm
≦40 ppm
Mo
52-55%
52.5-55.5%
O
≦10 ppm
≦10 ppm
N
≦10 ppm
≦10 ppm
Re
45-49%
44.5-47.5%
Ti
0.05-0.4%
0%
Y
0.005-0.07%
0.004-0.06%
Zr
0%
0.1-0.2%
Ex. 39
C
≦150 ppm
Mo
50-60%
O
≦100 ppm
N
≦40 ppm
Nb
≦5%
Rare Earth
≦4%
Metal
Re
40-50%
Ta
≦3%
Ti
≦1%
W
≦3%
Y
≦0.1%
Zn
≦0.1%
Zr
≦2%
Ex. 40
C
≦0.01%
Co
≦0.002%
Fe
≦0.02%
H
≦0.002%
Mo
52-53%
N
≦0.0008%
Ni
≦0.01%
O
≦0.06%
Re
47-48%
S
≦0.008%
Sn
≦0.002%
Ti
≦0.002%
W
≦0.02%
Ex. 41
Ex. 42
Ex. 43
Ex.44
C
0-50 ppm
0-50 ppm
0-50 ppm
0-50 ppm
Ca
0-1%
0-0.5%
0%
0%
Mg
0%
0-3%
0%
0%
Mo
0%
0-2%
0%
0%
O
0-50 ppm
0-50 ppm
0-50 ppm
0-50 ppm
N
0-50 ppm
0-50 ppm
0-50 ppm
0-50 ppm
Rare Earth
0-1%
0-0.5%
0%
0%
Metal
Re
0-6%
0-5%
0-4%
0%
Ta
85-96%
10-90%
85-95%
90.5-98%
W
4-15%
10-90%
5-15%
2-9.5%
Y
0%
0-1%
0%
0%
Zn
0%
0-1%
0%
0%
Zr
0%
0-1%
0%
0%
Ex. 45
Ex.46
C
0-50 ppm
0-50 ppm
Ca
0%
0%
Mg
0%
0%
Mo
0%
0%
O
0-50 ppm
0-50 ppm
N
0-50 ppm
0-50 ppm
Rare Earth
0%
0%
Metal
Re
0-4%
0%
Ta
95-98%
90-97.5%
W
2% to less than 5%
2.5-10%
Y
0%
0%
Zn
0%
0%
Zr
0%
0%
[0015] In Examples 1-3, 14, 16-19, and 20-22 above, the metal alloy is principally formed of rhenium and molybdenum and the content of other metals and/or impurities is less than about 0.1 weight percent of the metal alloy, the atomic ratio of carbon to oxygen is about 2.5-10:1 (i.e., weight ratio of about 1.88-7.5:1), the average grain size of the metal alloy is about 6-10 ASTM, the tensile elongation of the metal alloy is about 25-35%, the average density of the metal alloy is at least about 13.4 gm/cc, the average yield strength of the metal alloy is about 98-122 (ksi), the average ultimate tensile strength of the metal alloy is about 150-310 UTS (ksi), and an average Vickers hardness of 372-653 (i.e., Rockwell A Hardness of about 70-80 at 77° F., an average Rockwell C Hardness of about 39-58 at 77° F.). In Examples 4-7, 8-11, 12, 13, 15, and 32-38 above, the metal alloy is principally formed of rhenium and molybdenum and at least one metal of titanium, yttrium and/or zirconium, and the content of other metals and/or impurities is less than about 0.1 weight percent of the metal alloy, the ratio of carbon to oxygen is about 2.5-10:1, the average grain size of the metal alloy is about 6-10 ASTM, the tensile elongation of the metal alloy is about 25-35%, the average density of the metal alloy is at least about 13.6 gm/cc, the average yield strength of the metal alloy is at least about 110 (ksi), the average ultimate tensile strength of the metal alloy is about 150-310 UTS (ksi), and an average Vickers hardness of 372-653 (i.e., an average Rockwell A Hardness of about 70-80 at 77° F., an average Rockwell C Hardness of about 39-58 at 77° F.). The remaining alloys identified in the above examples may or may not include titanium, yttrium and/or zirconium. The properties of these alloys will be similar to the alloys discussed in the above examples. In Example 32, the weight ratio of titanium to zirconium is about 1.5-3:1. In Example 36, the weight ratio of titanium to zirconium is about 1.75-2.5:1. In Examples 29-32, the weight ratio of titanium to zirconium is about 1-10:1. In Example 40, the ratio of carbon to oxygen is at least about 0.4:1 (i.e., weight ratio of carbon to oxygen of at least about 0.3:1), the nitrogen content is less than the carbon content and the oxygen content, the atomic ratio of carbon to nitrogen is at least about 4:1 (i.e., weight ratio of about 3.43:1), the atomic ratio of oxygen to nitrogen is at least about 3:1 (i.e., weight ratio of about 3.42:1), the average grain size of metal alloy is about 6-10 ASTM, the tensile elongation of the metal alloy is about 25-35%, the average density of the metal alloy is at least about 13.4 gm/cc, the average yield strength of the metal alloy is about 98-122 (ksi), the average ultimate tensile strength of the metal alloy is about 100-150 UTS (ksi), and the average hardness of the metal alloy is about 80-100 (HRC) at 77° F.
[0016] In Examples 41-46, the metal alloy is principally formed of tungsten and tantalum and the content of other metals and/or impurities is less than about 0.1 weight percent, and typically less than 0.04 weight percent of the metal alloy.
[0017] In another and/or alternative non-limiting aspect of the present invention, the use of the metal alloy in the medical device can increase the strength of the medical device as compared with stainless steel or chromium-cobalt alloys, thus less quantity of metal alloy can be used in the medical device to achieve similar strengths as compared to medical devices formed of different metals. As such, the resulting medical device can be made smaller and less bulky by use of the metal alloy without sacrificing the strength and durability of the medical device. Such a medical device can have a smaller profile, thus can be inserted in smaller areas, openings and/or passageways. The metal alloy also can increase the radial strength of the medical device. For instance, the thickness of the walls of the medical device and/or the wires used to form the medical device can be made thinner and achieve a similar or improved radial strength as compared with thicker walled medical devices formed of stainless steel or cobalt and chromium alloy. The metal alloy also can improve stress-strain properties, bendability and flexibility of the medical device, thus increase the life of the medical device. For instance, the medical device can be used in regions that subject the medical device to bending. Due to the improved physical properties of the medical device from the metal alloy, the medical device has improved resistance to fracturing in such frequent bending environments. In addition or alternatively, the improved bendability and flexibility of the medical device due to the use of the metal alloy can enable the medical device to be more easily inserted into various regions of a body. The metal alloy can also reduce the degree of recoil during the crimping and/or expansion of the medical device. For example, the medical device better maintains its crimped form and/or better maintains its expanded form after expansion due to the use of the metal alloy. As such, when the medical device is to be mounted onto a delivery device when the medical device is crimped, the medical device better maintains its smaller profile during the insertion of the medical device in various regions of a body. Also, the medical device better maintains its expanded profile after expansion so as to facilitate in the success of the medical device in the treatment area. In addition to the improved physical properties of the medical device by use of the metal alloy, the metal alloy has improved radiopaque properties as compared to standard materials such as stainless steel or cobalt-chromium alloy, thus reducing or eliminating the need for using marker materials on the medical device. For instance, the metal alloy is believed to at least about 10-20% more radiopaque than stainless steel or cobalt-chromium alloy. Specifically, the metal alloy is believed to be at least about 33% more radiopaque than cobalt-chromium alloy and is believed to be at least about 41.5% more radiopaque than stainless steel.
[0018] In a further and/or alternative non-limiting aspect of the invention, the medical device can include a bistable construction. In such a design, the medical device has two or more stable configurations, including a first stable configuration with a first cross-sectional shape and a second stable configuration with a second cross-sectional shape. All or a portion of the medical device can include the bistable construction. The bistable construction can result in a generally uniform change in shape of the medical device, or one portion of the medical device can change into one or more configurations and one or more other portions of the medical device can change into one or more other configurations.
[0019] In yet another and/or alternative non-limiting aspect of the present invention, the medical device can include, contain and/or be coated with one or more agents that facilitate in the success of the medical device and/or treated area. The term “agent” includes, but is not limited to a substance, pharmaceutical, biologic, veterinary product, drug, and analogs or derivatives otherwise formulated and/or designed to prevent, inhibit and/or treat one or more clinical and/or biological events, and/or to promote healing. Non-limiting examples of clinical events that can be addressed by one or more agents include, but are not limited to viral, fungus and/or bacterial infection; vascular diseases and/or disorders; digestive diseases and/or disorders; reproductive diseases and/or disorders; lymphatic diseases and/or disorders; cancer; implant rejection; pain; nausea; swelling; arthritis; bone diseases and/or disorders; organ failure; immunity diseases and/or disorders; cholesterol problems; blood diseases and/or disorders; lung diseases and/or disorders; heart diseases and/or disorders; brain diseases and/or disorders; neuralgia diseases and/or disorders; kidney diseases and/or disorders; ulcers; liver diseases and/or disorders; intestinal diseases and/or disorders; gallbladder diseases and/or disorders; pancreatic diseases and/or disorders; psychological disorders; respiratory diseases and/or disorders; gland diseases and/or disorders; skin diseases and/or disorders; hearing diseases and/or disorders; oral diseases and/or disorders; nasal diseases and/or disorders; eye diseases and/or disorders; fatigue; genetic diseases and/or disorders; burns; scarring and/or scars; trauma; weight diseases and/or disorders; addiction diseases and/or disorders; hair loss; cramps; muscle spasms; tissue repair; nerve repair; neural regeneration and/or the like. Non-limiting examples of agents that can be used include, but are not limited to, 5-Fluorouracil and/or derivatives thereof; 5-Phenylmethimazole and/or derivatives thereof; ACE inhibitors and/or derivatives thereof; acenocoumarol and/or derivatives thereof; acyclovir and/or derivatives thereof; actilyse and/or derivatives thereof; adrenocorticotropic hormone and/or derivatives thereof; adriamycin and/or derivatives thereof; agents that modulate intracellular Ca 2 + transport such as L-type (e.g., diltiazem, nifedipine, verapamil, etc.) or T-type Ca 2 + channel blockers (e.g., amiloride, etc.); alpha-adrenergic blocking agents and/or derivatives thereof; alteplase and/or derivatives thereof; amino glycosides and/or derivatives thereof (e.g., gentamycin, tobramycin, etc.); angiopeptin and/or derivatives thereof; angiostatic steroid and/or derivatives thereof; angiotensin II receptor antagonists and/or derivatives thereof; anistreplase and/or derivatives thereof; antagonists of vascular epithelial growth factor and/or derivatives thereof; anti-biotics; anti-coagulant compounds and/or derivatives thereof; anti-fibrosis compounds and/or derivatives thereof; antifungal compounds and/or derivatives thereof; anti-inflammatory compounds and/or derivatives thereof; Anti-Invasive Factor and/or derivatives thereof; anti-metabolite compounds and/or derivatives thereof (e.g., staurosporin, trichothecenes, and modified diphtheria and ricin toxins, Pseudomonas exotoxin, etc.); anti-matrix compounds and/or derivatives thereof (e.g., colchicine, tamoxifen, etc.); anti-microbial agents and/or derivatives thereof; anti-migratory agents and/or derivatives thereof (e.g., caffeic acid derivatives, nilvadipine, etc.); anti-mitotic compounds and/or derivatives thereof; anti-neoplastic compounds and/or derivatives thereof; anti-oxidants and/or derivatives thereof; anti-platelet compounds and/or derivatives thereof; anti-proliferative and/or derivatives thereof; anti-thrombogenic agents and/or derivatives thereof; argatroban and/or derivatives thereof; ap-1 inhibitors and/or derivatives thereof (e.g., for tyrosine kinase, protein kinase C, myosin light chain kinase, Ca 2 +/calmodulin kinase II, casein kinase II, etc.); aspirin and/or derivatives thereof; azathioprine and/or derivatives thereof; β-Estradiol and/or derivatives thereof; β-1-anticollagenase and/or derivatives thereof; calcium channel blockers and/or derivatives thereof; calmodulin antagonists and/or derivatives thereof (e.g., H7, etc.); CAPTOPRIL and/or derivatives thereof; cartilage-derived inhibitor and/or derivatives thereof; ChIMP-3 and/or derivatives thereof; cephalosporin and/or derivatives thereof (e.g., cefadroxil, cefazolin, cefaclor, etc.); chloroquine and/or derivatives thereof; chemotherapeutic compounds and/or derivatives thereof (e.g., 5-fluorouracil, vincristine, vinblastine, cisplatin, doxyrubicin, adriamycin, tamocifen, etc.); chymostatin and/or derivatives thereof; CILAZAPRIL and/or derivatives thereof; clopidigrel and/or derivatives thereof; clotrimazole and/or derivatives thereof; colchicine and/or derivatives thereof; cortisone and/or derivatives thereof; coumadin and/or derivatives thereof; curacin-A and/or derivatives thereof; cyclosporine and/or derivatives thereof; cytochalasin and/or derivatives thereof (e.g., cytochalasin A, cytochalasin B, cytochalasin C, cytochalasin D, cytochalasin E, cytochalasin F, cytochalasin G, cytochalasin H, cytochalasin J, cytochalasin K, cytochalasin L, cytochalasin M, cytochalasin N, cytochalasin 0, cytochalasin P, cytochalasin Q, cytochalasin R, cytochalasin S, chaetoglobosin A, chaetoglobosin B, chaetoglobosin C, chaetoglobosin D, chaetoglobosin E, chaetoglobosin F, chaetoglobosin G, chaetoglobosin J, chaetoglobosin K, deoxaphomin, proxiphomin, protophomin, zygosporin D, zygosporin E, zygosporin F, zygosporin G, aspochalasin B, aspochalasin C, aspochalasin D, etc.); cytokines and/or derivatives thereof; desirudin and/or derivatives thereof; dexamethazone and/or derivatives thereof; dipyridamole and/or derivatives thereof; eminase and/or derivatives thereof; endothelin and/or derivatives thereof endothelial growth factor and/or derivatives thereof; epidermal growth factor and/or derivatives thereof; epothilone and/or derivatives thereof; estramustine and/or derivatives thereof; estrogen and/or derivatives thereof; fenoprofen and/or derivatives thereof; fluorouracil and/or derivatives thereof; flucytosine and/or derivatives thereof; forskolin and/or derivatives thereof; ganciclovir and/or derivatives thereof; glucocorticoids and/or derivatives thereof (e.g., dexamethasone, betamethasone, etc.); glycoprotein IIb/IIIa platelet membrane receptor antibody and/or derivatives thereof; GM-CSF and/or derivatives thereof; griseofulvin and/or derivatives thereof; growth factors and/or derivatives thereof (e.g., VEGF; TGF; IGF; PDGF; FGF, etc.); growth hormone and/or derivatives thereof; heparin and/or derivatives thereof; hirudin and/or derivatives thereof; hyaluronate and/or derivatives thereof; hydrocortisone and/or derivatives thereof; ibuprofen and/or derivatives thereof; immunosuppressive agents and/or derivatives thereof (e.g., adrenocorticosteroids, cyclosporine, etc.); indomethacin and/or derivatives thereof; inhibitors of the sodium/calcium antiporter and/or derivatives thereof (e.g., amiloride, etc.); inhibitors of the IP3 receptor and/or derivatives thereof; inhibitors of the sodium/hydrogen antiporter and/or derivatives thereof (e.g., amiloride and derivatives thereof; etc.); insulin and/or derivatives thereof; Interferon α Macroglobulin and/or derivatives thereof; ketoconazole and/or derivatives thereof; Lepirudin and/or derivatives thereof; LISINOPRIL and/or derivatives thereof; LOVASTATIN and/or derivatives thereof; marevan and/or derivatives thereof; mefloquine and/or derivatives thereof; metalloproteinase inhibitors and/or derivatives thereof; methotrexate and/or derivatives thereof; metronidazole and/or derivatives thereof; miconazole and/or derivatives thereof; monoclonal antibodies and/or derivatives thereof; mutamycin and/or derivatives thereof; naproxen and/or derivatives thereof; nitric oxide and/or derivatives thereof; nitroprusside and/or derivatives thereof; nucleic acid analogues and/or derivatives thereof (e.g., peptide nucleic acids, etc.); nystatin and/or derivatives thereof; oligonucleotides and/or derivatives thereof; paclitaxel and/or derivatives thereof; penicillin and/or derivatives thereof; pentamidine isethionate and/or derivatives thereof; phenindione and/or derivatives thereof; phenylbutazone and/or derivatives thereof; phosphodiesterase inhibitors and/or derivatives thereof; Plasminogen Activator Inhibitor-1 and/or derivatives thereof; Plasminogen Activator Inhibitor-2 and/or derivatives thereof; Platelet Factor 4 and/or derivatives thereof; platelet derived growth factor and/or derivatives thereof; plavix and/or derivatives thereof; POSTMI 75 and/or derivatives thereof; prednisone and/or derivatives thereof; prednisolone and/or derivatives thereof; probucol and/or derivatives thereof; progesterone and/or derivatives thereof; prostacyclin and/or derivatives thereof; prostaglandin inhibitors and/or derivatives thereof; protamine and/or derivatives thereof; protease and/or derivatives thereof; protein kinase inhibitors and/or derivatives thereof (e.g., staurosporin, etc.); quinine and/or derivatives thereof; radioactive agents and/or derivatives thereof (e.g., Cu-64, Ca-67, Cs-131, Ga-68, Zr-89, Ku-97, Tc-99m, Rh-105, Pd-103, Pd-109, In-111, 1-123, 1-125, 1-131, Re-186, Re-188, Au-198, Au-199, Pb-203, At-211, Pb-212, Bi-212, H3P3204, etc.); rapamycin and/or derivatives thereof; receptor antagonists for histamine and/or derivatives thereof; refludan and/or derivatives thereof; retinoic acids and/or derivatives thereof; revasc and/or derivatives thereof; rifamycin and/or derivatives thereof; sense or anti-sense oligonucleotides and/or derivatives thereof (e.g., DNA, RNA, plasmid DNA, plasmid RNA, etc.); seramin and/or derivatives thereof; steroids; seramin and/or derivatives thereof; serotonin and/or derivatives thereof; serotonin blockers and/or derivatives thereof; streptokinase and/or derivatives thereof; sulfasalazine and/or derivatives thereof; sulfonamides and/or derivatives thereof (e.g., sulfamethoxazole, etc.); sulphated chitin derivatives; Sulphated Polysaccharide Peptidoglycan Complex and/or derivatives thereof; TH1 and/or derivatives thereof (e.g., Interleukins-2, -12, and -15, gamma interferon, etc.); thioprotese inhibitors and/or derivatives thereof; taxol and/or derivatives thereof (e.g., taxotere, baccatin, 10-deacetyltaxol, 7-xylosyl-10-deacetyltaxol, cephalomannine, 10-deacetyl-7-epitaxol, 7 epitaxol, 10-deacetylbaccatin III, 10-deacetylcephaolmannine, etc.); ticlid and/or derivatives thereof; ticlopidine and/or derivatives thereof; tick anti-coagulant peptide and/or derivatives thereof; thioprotese inhibitors and/or derivatives thereof; thyroid hormone and/or derivatives thereof; Tissue Inhibitor of Metalloproteinase-1 and/or derivatives thereof; Tissue Inhibitor of Metalloproteinase-2 and/or derivatives thereof; tissue plasma activators; TNF and/or derivatives thereof, tocopherol and/or derivatives thereof; toxins and/or derivatives thereof; tranilast and/or derivatives thereof; transforming growth factors alpha and beta and/or derivatives thereof; trapidil and/or derivatives thereof; triazolopyrimidine and/or derivatives thereof; vapiprost and/or derivatives thereof; vinblastine and/or derivatives thereof; vincristine and/or derivatives thereof; zidovudine and/or derivatives thereof. As can be appreciated, the agent can include one or more derivatives of the above listed compounds and/or other compounds. In one non-limiting embodiment, the agent includes, but is not limited to, trapidil, Trapidil derivatives, taxol, taxol derivatives (e.g., taxotere, baccatin, 10-deacetyltaxol, 7-xylosyl-10-deacetyltaxol, cephalomannine, 10-deacetyl-7-epitaxol, 7 epitaxol, 10-deacetylbaccatin III, 10-deacetylcephaolmannine, etc.), cytochalasin, cytochalasin derivatives (e.g., cytochalasin A, cytochalasin B, cytochalasin C, cytochalasin D, cytochalasin E, cytochalasin F, cytochalasin G, cytochalasin H, cytochalasin J, cytochalasin K, cytochalasin L, cytochalasin M, cytochalasin N, cytochalasin O, cytochalasin P, cytochalasin Q, cytochalasin R, cytochalasin S, chaetoglobosin A, chaetoglobosin B, chaetoglobosin C, chaetoglobosin D, chaetoglobosin E, chaetoglobosin F, chaetoglobosin G, chaetoglobosin J, chaetoglobosin K, deoxaphomin, proxiphomin, protophomin, zygosporin D, zygosporin E, zygosporin F, zygosporin G, aspochalasin B, aspochalasin C, aspochalasin D, etc.), paclitaxel, paclitaxel derivatives, rapamycin, rapamycin derivatives, 5-Phenylmethimazole, 5-Phenylmethimazole derivatives, GM-CSF (granulo-cytemacrophage colony-stimulating-factor), GM-CSF derivatives, statins or HMG-CoA reductase inhibitors forming a class of hypolipidemic agents, combinations, or analogs thereof, or combinations thereof The type and/or amount of agent included in the device and/or coated on the device can vary. When two or more agents are included in and/or coated on the device, the amount of two or more agents can be the same or different. The type and/or amount of agent included on, in and/or in conjunction with the device are generally selected to address one or more clinical events. Typically the amount of agent included on, in and/or used in conjunction with the device is about 0.01-100 ug per mm 2 and/or at least about 0.01 weight percent of device; however, other amounts can be used. In one non-limiting embodiment of the invention, the device can be partially of fully coated and/or impregnated with one or more agents to facilitate in the success of a particular medical procedure. The amount of two of more agents on, in and/or used in conjunction with the device can be the same or different. The one or more agents can be coated on and/or impregnated in the device by a variety of mechanisms such as, but not limited to, spraying (e.g., atomizing spray techniques, etc.), flame spray coating, powder deposition, dip coating, flow coating, dip-spin coating, roll coating (direct and reverse), sonication, brushing, plasma deposition, depositing by vapor deposition, MEMS technology, and rotating mold deposition. In another and/or alternative non-limiting embodiment of the invention, the type and/or amount of agent included on, in and/or in conjunction with the device is generally selected for the treatment of one or more clinical events. Typically the amount of agent included on, in and/or used in conjunction with the device is about 0.01-100 ug per mm 2 and/or at least about 0.01-100 weight percent of the device; however, other amounts can be used. The amount of two of more agents on, in and/or used in conjunction with the device can be the same or different. As such, the medical device, when it includes, contains, and/or is coated with one or more agents, can include one or more agents to address one or more medical needs. In one non-limiting embodiment of the invention, the medical device can be partially of fully coated with one or more agents, impregnated with one or more agents to facilitate in the success of a particular medical procedure. The one or more agents can be coated on and/or impregnated in the medical device by a variety of mechanisms such as, but not limited to, spraying (e.g., atomizing spray techniques, etc.), dip coating, roll coating, sonication, brushing, plasma deposition, depositing by vapor deposition. In another and/or alternative non-limiting embodiment of the invention, the type and/or amount of agent included on, in and/or in conjunction with the medical device is generally selected for the treatment of one or more medical treatments. Typically, the amount of agent included on, in and/or used in conjunction with the medical device is about 0.01-100 ug per mm 2 ; however, other amounts can be used. The amount of two or more agents on, in and/or used in conjunction with the medical device can be the same or different.
[0020] In a further and/or alternative non-limiting aspect of the present invention, the one or more agents on and/or in the medical device, when used on the medical device, can be released in a controlled manner so the area in question to be treated is provided with the desired dosage of agent over a sustained period of time. As can be appreciated, controlled release of one or more agents on the medical device is not always required and/or desirable. As such, one or more of the agents on and/or in the medical device can be uncontrollably released from the medical device during and/or after insertion of the medical device in the treatment area. It can also be appreciated that one or more agents on and/or in the medical device can be controllably released from the medical device and one or more agents on and/or in the medical device can be uncontrollably released from the medical device. It can also be appreciated that one or more agents on and/or in one region of the medical device can be controllably released from the medical device and one or more agents on and/or in the medical device can be uncontrollably released from another region on the medical device. As such, the medical device can be designed such that 1) all the agent on and/or in the medical device is controllably released, 2) some of the agent on and/or in the medical device is controllably released and some of the agent on the medical device is non-controllably released, or 3) none of the agent on and/or in the medical device is controllably released. The medical device can also be designed such that the rate of release of the one or more agents from the medical device is the same or different. The medical device can also be designed such that the rate of release of the one or more agents from one or more regions on the medical device is the same or different. Non-limiting arrangements that can be used to control the release of one or more agent from the medical device include a) at least partially coat one or more agents with one or more polymers, b) at least partially incorporate and/or at least partially encapsulate one or more agents into and/or with one or more polymers, and/or c) insert one or more agents in pores, passageway, cavities, etc. in the medical device and at least partially coat or cover such pores, passageway, cavities, etc. with one or more polymers. As can be appreciated, other or additional arrangements can be used to control the release of one or more agent from the medical device. The one or more polymers used to at least partially control the release of one or more agent from the medical device can be porous or non-porous. The one or more agents can be inserted into and/or applied to one or more surface structures and/or micro-structures on the medical device, and/or be used to at least partially form one or more surface structures and/or micro-structures on the medical device. As such, the one or more agents on the medical device can be 1) coated on one or more surface regions of the medical device, 2) inserted and/or impregnated in one or more surface structures and/or micro-structures, etc. of the medical device, and/or 3) form at least a portion or be included in at least a portion of the structure of the medical device. When the one or more agents are coated on the medical device, the one or more agents can 1) be directly coated on one or more surfaces of the medical device, 2) be mixed with one or more coating polymers or other coating materials and then at least partially coated on one or more surfaces of the medical device, 3) be at least partially coated on the surface of another coating material that has been at least partially coated on the medical device, and/or 4) be at least partially encapsulated between a) a surface or region of the medical device and one or more other coating materials and/or b) two or more other coating materials. As can be appreciated, many other coating arrangements can be additionally or alternatively used. When the one or more agents are inserted and/or impregnated in one or more internal structures, surface structures and/or micro-structures of the medical device, 1) one or more other coating materials can be applied at least partially over the one or more internal structures, surface structures and/or micro-structures of the medical device, and/or 2) one or more polymers can be combined with one or more agents. As such, the one or more agents can be 1) embedded in the structure of the medical device; 2) positioned in one or more internal structures of the medical device; 3) encapsulated between two polymer coatings; 4) encapsulated between the base structure and a polymer coating; 5) mixed in the base structure of the medical device that includes at least one polymer coating; or 6) one or more combinations of 1, 2, 3, 4 and/or 5. In addition or alternatively, the one or more coating of the one or more polymers on the medical device can include 1) one or more coatings of non-porous polymers; 2) one or more coatings of a combination of one or more porous polymers and one or more non-porous polymers; 3) one or more coating of porous polymer, or 4) one or more combinations of options 1, 2, and 3. As can be appreciated different agents can be located in and/or between different polymer coating layers and/or on and/or the structure of the medical device. As can also be appreciated, many other and/or additional coating combinations and/or configurations can be used. The concentration of one or more agents, the type of polymer, the type and/or shape of internal structures in the medical device and/or the coating thickness of one or more agents can be used to control the release time, the release rate and/or the dosage amount of one or more agents; however, other or additional combinations can be used. As such, the agent and polymer system combination and location on the medical device can be numerous. As can also be appreciated, one or more agents can be deposited on the top surface of the medical device to provide an initial uncontrolled burst effect of the one or more agents prior to 1) the controlled release of the one or more agents through one or more layers of polymer system that include one or more non-porous polymers and/or 2) the uncontrolled release of the one or more agents through one or more layers of polymer system. The one or more agents and/or polymers can be coated on the medical device by a variety of mechanisms such as, but not limited to, spraying (e.g., atomizing spray techniques, etc.), dip coating, roll coating, sonication, brushing, plasma deposition, and/or depositing by vapor deposition. The thickness of each polymer layer and/or layer of agent is generally at least about 0.01 μm and is generally less than about 150 μm. In one non-limiting embodiment, the thickness of a polymer layer and/or layer of agent is about 0.02-75 μm, more particularly about 0.05-50 μm, and even more particularly about 1-30 μm. When the medical device includes and/or is coated with one or more agents such that at least one of the agents is at least partially controllably released from the medical device, the need or use of body-wide therapy for extended periods of time can be reduced or eliminated. In the past, the use of body-wide therapy was used by the patient long after the patient left the hospital or other type of medical facility. This body-wide therapy could last days, weeks, months or sometimes over a year after surgery. The medical device of the present invention can be applied or inserted into a treatment area and 1) merely requires reduced use and/or extended use of body-wide therapy after application or insertion of the medical device or 2) does not require use and/or extended use of body-wide therapy after application or insertion of the medical device. As can be appreciated, use and/or extended use of body-wide therapy can be used after application or insertion of the medical device at the treatment area. In one non-limiting example, no body-wide therapy is needed after the insertion of the medical device into a patient. In another and/or alternative non-limiting example, short term use of body-wide therapy is needed or used after the insertion of the medical device into a patient. Such short term use can be terminated after the release of the patient from the hospital or other type of medical facility, or one to two days or weeks after the release of the patient from the hospital or other type of medical facility; however, it will be appreciated that other time periods of body-wide therapy can be used. As a result of the use of the medical device of the present invention, the use of body-wide therapy after a medical procedure involving the insertion of a medical device into a treatment area can be significantly reduced or eliminated.
[0021] In another and/or alternative non-limiting aspect of the present invention, controlled release of one or more agents from the medical device, when controlled release is desired, can be accomplished by using one or more non-porous polymer layers; however, other and/or additional mechanisms can be used to controllably release the one or more agents. The one or more agents are at least partially controllably released by molecular diffusion through the one or more non-porous polymer layers. When one or more non-porous polymer layers are used, the one or more polymer layers are typically biocompatible polymers; however, this is not required. The one or more non-porous polymers can be applied to the medical device without the use of chemical, solvents, and/or catalysts; however, this is not required. In one non-limiting example, the non-porous polymer can be at least partially applied by, but not limited to, vapor deposition and/or plasma deposition. The non-porous polymer can be selected so as to polymerize and cure merely upon condensation from the vapor phase; however, this is not required. The application of the one or more non-porous polymer layers can be accomplished without increasing the temperature above ambient temperature (e.g., 65-90° F.); however, this is not required. The non-porous polymer system can be mixed with one or more agents prior to being coated on the medical device and/or be coated on a medical device that previously included one or more agents; however, this is not required. The use or one or more non-porous polymer layers allow for accurate controlled release of the agent from the medical device. The controlled release of one or more agents through the non-porous polymer is at least partially controlled on a molecular level utilizing the motility of diffusion of the agent through the non-porous polymer. In one non-limiting example, the one or more non-porous polymer layers can include, but are not limited to, polyamide, parylene (e.g., parylene C, parylene N) and/or a parylene derivative.
[0022] In still another and/or alternative non-limiting aspect of the present invention, controlled release of one or more agents from the medical device, when controlled release is desired, can be accomplished by using one or more polymers that form a chemical bond with one or more agents. In one non-limiting example, at least one agent includes trapidil, trapidil derivative or a salt thereof that is covalently bonded to at least one polymer such as, but not limited to, an ethylene-acrylic acid copolymer. The ethylene is the hydrophobic group and acrylic acid is the hydrophilic group. The mole ratio of the ethylene to the acrylic acid in the copolymer can be used to control the hydrophobicity of the copolymer. The degree of hydrophobicity of one or more polymers can also be used to control the release rate of one or more agents from the one or more polymers. The amount of agent that can be loaded with one or more polymers may be a function of the concentration of anionic groups and/or cationic groups in the one or more polymer. For agents that are anionic, the concentration of agent that can be loaded on the one or more polymers is generally a function of the concentration of cationic groups (e.g. amine groups and the like) in the one or more polymer and the fraction of these cationic groups that can ionically bind to the anionic form of the one or more agents. For agents that are cationic (e.g., trapidil, etc.), the concentration of agent that can be loaded on the one or more polymers is generally a function of the concentration of anionic groups (i.e., carboxylate groups, phosphate groups, sulfate groups, and/or other organic anionic groups) in the one or more polymers, and the fraction of these anionic groups that can ionically bind to the cationic form of the one or more agents. As such, the concentration of one or more agent that can be bound to the one or more polymers can be varied by controlling the amount of hydrophobic and hydrophilic monomer in the one or more polymers, by controlling the efficiency of salt formation between the agent, and/or the anionic/cationic groups in the one or more polymers.
[0023] In still another and/or alternative non-limiting aspect of the present invention, controlled release of one or more agents from the medical device, when controlled release is desired, can be accomplished by using one or more polymers that include one or more induced cross-links. These one or more cross-links can be used to at least partially control the rate of release of the one or more agents from the one or more polymers. The cross-linking in the one or more polymers can be instituted by a number to techniques such as, but not limited to, using catalysts, using radiation, using heat, and/or the like. The one or more cross-links formed in the one or more polymers can result in the one or more agents to become partially or fully entrapped within the cross-linking, and/or form a bond with the cross-linking As such, the partially or fully entrapped agent takes longer to release itself from the cross-linking, thereby delaying the release rate of the one or more agents from the one or more polymers. Consequently, the amount of agent, and/or the rate at which the agent is released from the medical device over time can be at least partially controlled by the amount or degree of cross-linking in the one or more polymers.
[0024] In still a further and/or alternative aspect of the present invention, a variety of polymers can be coated on the medical device and/or be used to form at least a portion of the medical device. The one or more polymers can be used on the medical for a variety of reasons such as, but not limited to, 1) forming a portion of the medical device, 2) improving a physical property of the medical device (e.g., improve strength, improve durability, improve biocompatibility, reduce friction, etc.), 3) forming a protective coating on one or more surface structures on the medical device, 4) at least partially forming one or more surface structures on the medical device, and/or 5) at least partially controlling a release rate of one or more agents from the medical device. As can be appreciated, the one or more polymers can have other or additional uses on the medical device. The one or more polymers can be porous, non-porous, biostable, biodegradable (i.e., dissolves, degrades, is absorbed, or any combination thereof in the body), and/or biocompatible. When the medical device is coated with one or more polymers, the polymer can include 1) one or more coatings of non-porous polymers; 2) one or more coatings of a combination of one or more porous polymers and one or more non-porous polymers; 3) one or more coatings of one or more porous polymers and one or more coatings of one or more non-porous polymers; 4) one or more coatings of porous polymer, or 5) one or more combinations of options 1, 2, 3 and 4. The thickness of one or more of the polymer layers can be the same or different. When one or more layers of polymer are coated onto at least a portion of the medical device, the one or more coatings can be applied by a variety of techniques such as, but not limited to, vapor deposition and/or plasma deposition, spraying, dip-coating, roll coating, sonication, atomization, brushing and/or the like; however, other or additional coating techniques can be used. The one or more polymers that can be coated on the medical device and/or used to at least partially form the medical device can be polymers that are considered to be biodegradable, bioresorbable, or bioerodable; polymers that are considered to be biostable; and/or polymers that can be made to be biodegradable and/or bioresorbable with modification. Non-limiting examples of polymers that are considered to be biodegradable, bioresorbable, or bioerodable include, but are not limited to, aliphatic polyesters; poly(glycolic acid) and/or copolymers thereof (e.g., poly(glycolide trimethylene carbonate); poly(caprolactone glycolide)); poly(lactic acid) and/or isomers thereof (e.g., poly-L(lactic acid) and/or poly-D Lactic acid) and/or copolymers thereof (e.g. DL-PLA), with and without additives (e.g. calcium phosphate glass), and/or other copolymers (e.g. poly(caprolactone lactide), poly(lactide glycolide), poly(lactic acid ethylene glycol)); poly(ethylene glycol); poly(ethylene glycol) diacrylate; poly(lactide); polyalkylene succinate; polybutylene diglycolate; polyhydroxybutyrate (PHB); polyhydroxyvalerate (PHV); polyhydroxybutyrate/polyhydroxyvalerate copolymer (PHB/PHV); poly(hydroxybutyrate-co-valerate); polyhydroxyalkaoates (PHA); polycaprolactone; poly(caprolactone-polyethylene glycol) copolymer; poly(valerolactone); polyanhydrides; poly(orthoesters) and/or blends with polyanhydrides; poly(anhydride-co-imide); polycarbonates (aliphatic); poly(hydroxyl-esters); polydioxanone; polyanhydrides; polyanhydride esters; polycyanoacrylates; poly(alkyl 2-cyanoacrylates); poly(amino acids); poly(phosphazenes); poly(propylene fumarate); poly(propylene fumarate-co-ethylene glycol); poly(fumarate anhydrides); fibrinogen; fibrin; gelatin; cellulose and/or cellulose derivatives and/or cellulosic polymers (e.g., cellulose acetate, cellulose acetate butyrate, cellulose butyrate, cellulose ethers, cellulose nitrate, cellulose propionate, cellophane); chitosan and/or chitosan derivatives (e.g., chitosan NOCC, chitosan NOOC-G); alginate; polysaccharides; starch; amylase; collagen; polycarboxylic acids; poly(ethyl ester-co-carboxylate carbonate) (and/or other tyrosine derived polycarbonates); poly(iminocarbonate); poly(BPA-iminocarbonate); poly(trimethylene carbonate); poly(iminocarbonate-amide) copolymers and/or other pseudo-poly(amino acids); poly(ethylene glycol); poly(ethylene oxide); poly(ethylene oxide)/poly(butylene terephthalate) copolymer; poly(epsilon-caprolactone-dimethyltrimethylene carbonate); poly(ester amide); poly(amino acids) and conventional synthetic polymers thereof; poly(alkylene oxalates); poly(alkylcarbonate); poly(adipic anhydride); nylon copolyamides; NO-carboxymethyl chitosan NOCC); carboxymethyl cellulose; copoly(ether-esters) (e.g., PEO/PLA dextrans); polyketals; biodegradable polyethers; biodegradable polyesters; polydihydropyrans; polydepsipeptides; polyarylates (L-tyrosine-derived) and/or free acid polyarylates; polyamides (e.g., Nylon 66, polycaprolactam); poly(propylene fumarate-co-ethylene glycol) (e.g., fumarate anhydrides); hyaluronates; poly-p-dioxanone; polypeptides and proteins; polyphosphoester; polyphosphoester urethane; polysaccharides; pseudo-poly(amino acids); starch; terpolymer; (copolymers of glycolide, lactide, or dimethyltrimethylene carbonate); rayon; rayon triacetate; latex; and/pr copolymers, blends, and/or composites of above. Non-limiting examples of polymers that considered to be biostable include, but are not limited to, parylene; parylene c; parylene f; parylene n; parylene derivatives; maleic anyhydride polymers; phosphorylcholine; poly n-butyl methacrylate (PBMA); polyethylene-co-vinyl acetate (PEVA); PBMA/PEVA blend or copolymer; polytetrafluoroethene (Teflon®) and derivatives; poly-paraphenylene terephthalamide (Kevlar®); poly(ether ether ketone) (PEEK); poly(styrene-b-isobutylene-b-styrene) (Translute™); tetramethyldisiloxane (side chain or copolymer); polyimides polysulfides; poly(ethylene terephthalate); poly(methyl methacrylate); poly(ethylene-co-methyl methacrylate); styrene-ethylene/butylene-styrene block copolymers; ABS; SAN; acrylic polymers and/or copolymers (e.g., n-butyl-acrylate, n-butyl methacrylate, 2-ethylhexyl acrylate, lauryl-acrylate, 2-hydroxy-propyl acrylate, polyhydroxyethyl, methacrylate/methylmethacrylate copolymers); glycosaminoglycans; alkyd resins; elastin; polyether sulfones; epoxy resin; poly(oxymethylene); polyolefins; polymers of silicone; polymers of methane; polyisobutylene; ethylene-alphaolefin copolymers; polyethylene; polyacrylonitrile; fluorosilicones; poly(propylene oxide); polyvinyl aromatics (e.g. polystyrene); poly(vinyl ethers) (e.g. polyvinyl methyl ether); poly(vinyl ketones); poly(vinylidene halides) (e.g. polyvinylidene fluoride, polyvinylidene chloride); poly(vinylpyrolidone); poly(vinylpyrolidone)/vinyl acetate copolymer; polyvinylpridine prolastin or silk-elastin polymers (SELP); silicone; silicone rubber; polyurethanes (polycarbonate polyurethanes, silicone urethane polymer) (e.g., chronoflex varieties, bionate varieties); vinyl halide polymers and/or copolymers (e.g. polyvinyl chloride); polyacrylic acid; ethylene acrylic acid copolymer; ethylene vinyl acetate copolymer; polyvinyl alcohol; poly(hydroxyl alkylmethacrylate); Polyvinyl esters (e.g. polyvinyl acetate); and/or copolymers, blends, and/or composites of above. Non-limiting examples of polymers that can be made to be biodegradable and/or bioresorbable with modification include, but are not limited to, hyaluronic acid (hyanluron); polycarbonates; polyorthocarbonates; copolymers of vinyl monomers; polyacetals; biodegradable polyurethanes; polyacrylamide; polyisocyanates; polyamide; and/or copolymers, blends, and/or composites of above. As can be appreciated, other and/or additional polymers and/or derivatives of one or more of the above listed polymers can be used. The one or more polymers can be coated on the medical device by a variety of mechanisms such as, but not limited to, spraying (e.g., atomizing spray techniques, etc.), dip coating, roll coating, sonication, brushing, plasma deposition, and/or depositing by vapor deposition. The thickness of each polymer layer is generally at least about 0.01 μm and is generally less than about 150 μm; however, other thicknesses can be used. In one non-limiting embodiment, the thickness of a polymer layer and/or layer of agent is about 0.02-75 μm, more particularly about 0.05-50 μm, and even more particularly about 1-30 μm. As can be appreciated, other thicknesses can be used. In one non-limiting embodiment, the medical device includes and/or is coated with parylene, PLGA, POE, PGA, PLLA, PAA, PEG, chitosan and/or derivatives of one or more of these polymers. In another and/or alternative non-limiting embodiment, the medical device includes and/or is coated with a non-porous polymer that includes, but is not limited to, polyamide, parylene c, parylene n and/or a parylene derivative. In still another and/or alternative non-limiting embodiment, the medical device includes and/or is coated with poly(ethylene oxide), poly(ethylene glycol), and polypropylene oxide), polymers of silicone, methane, tetrafluoroethylene (including TEFLON® brand polymers), tetramethyldisiloxane, and the like.
[0025] In another and/or alternative non-limiting aspect of the present invention, the medical device, when including and/or is coated with one or more agents, can include and/or can be coated with one or more agents that are the same or different in different regions of the medical device and/or have differing amounts and/or concentrations in differing regions of the medical device. For instance, the medical device can a) be coated with and/or include one or more biologicals on at least one portion of the medical device and at least another portion of the medical device is not coated with and/or includes agent; b) be coated with and/or include one or more biologicals on at least one portion of the medical device that is different from one or more biologicals on at least another portion of the medical device; c) be coated with and/or include one or more biologicals at a concentration on at least one portion of the medical device that is different from the concentration of one or more biologicals on at least another portion of the medical device; etc.
[0026] In still another and/or alternative non-limiting aspect of the present invention, one or more surfaces of the medical device can be treated to achieve the desired coating properties of the one or more agents and one or more polymers coated on the medical device. Such surface treatment techniques include, but are not limited to, cleaning, buffing, smoothing, etching (chemical etching, plasma etching, etc.), etc. When an etching process is used, various gasses can be used for such a surface treatment process such as, but not limited to, carbon dioxide, nitrogen, oxygen, Freon®, helium, hydrogen, etc. The plasma etching process can be used to clean the surface of the medical device, change the surface properties of the medical device so as to affect the adhesion properties, lubricity properties, etc. of the surface of the medical device. As can be appreciated, other or additional surface treatment processes can be used prior to the coating of one or more agents and/or polymers on the surface of the medical device. In one non-limiting manufacturing process, one or more portions of the medical device are cleaned and/or plasma etched; however, this is not required. Plasma etching can be used to clean the surface of the medical device, and/or to form one or more non-smooth surfaces on the medical device to facilitate in the adhesion of one or more coatings of agents and/or one or more coatings of polymer on the medical device. The gas for the plasma etching can include carbon dioxide and/or other gasses. Once one or more surface regions of the medical device have been treated, one or more coatings of polymer and/or agent can be applied to one or more regions of the medical device. For instance, 1) one or more layers of porous or non-porous polymer can be coated on an outer and/or inner surface of the medical device, 2) one or more layers of agent can be coated on an outer and/or inner surface of the medical device, or 3) one or more layers of porous or non-porous polymer that includes one or more agents can be coated on an outer and/or inner surface of the medical device. The one or more layers of agent can be applied to the medical device by a variety of techniques (e.g., dipping, rolling, brushing, spraying, particle atomization, etc.). One non-limiting coating technique is by an ultrasonic mist coating process wherein ultrasonic waves are used to break up the droplet of agent and form a mist of very fine droplets. These fine droplets have an average droplet diameter of about 0.1-3 microns. The fine droplet mist facilitates in the formation of a uniform coating thickness and can increase the coverage area on the medical device.
[0027] In still yet another and/or alternative non-limiting aspect of the present invention, one or more portions of the medical device can 1) include the same or different agents, 2) include the same or different amount of one or more agents, 3) include the same or different polymer coatings, 4) include the same or different coating thicknesses of one or more polymer coatings, 5) have one or more portions of the medical device controllably release and/or uncontrollably release one or more agents, and/or 6) have one or more portions of the medical device controllably release one or more agents and one or more portions of the medical device uncontrollably release one or more agents.
[0028] In yet another and/or alternative non-limiting aspect of the invention, the medical device can include a marker material that facilitates enabling the medical device to be properly positioned in various regions of a body. The marker material is typically designed to be visible to electromagnetic waves (e.g., x-rays, microwaves, visible light, inferred waves, ultraviolet waves, etc.); sound waves (e.g., ultrasound waves, etc.); magnetic waves (e.g., MRI, etc.); and/or other types of electromagnetic waves (e.g., microwaves, visible light, inferred waves, ultraviolet waves, etc.). In one non-limiting embodiment, the marker material is visible to x-rays (i.e., radiopaque). The marker material can form all or a portion of the medical device and/or be coated on one or more portions (flaring portion and/or body portion; at ends of medical device; at or near transition of body portion and flaring section; etc.) of the medical device. The location of the marker material can be on one or multiple locations on the medical device. The size of the one or more regions that include the marker material can be the same or different. The marker material can be spaced at defined distances from one another so as to form ruler like markings on the medical device to facilitate in the positioning of the medical device in various regions of a body. The marker material can be a rigid or flexible material. The marker material can be a biostable or biodegradable material. When the marker material is a rigid material, the marker material is typically formed of a metal material (e.g., metal band, metal plating, etc.); however, other or additional materials can be used. The metal which at least partially forms the medical device can function as a marker material; however, this is not required. When the marker material is a flexible material, the marker material typically is formed of one or more polymers that are marker materials in-of-themselves and/or include one or more metal powders and/or metal compounds. In one non-limiting embodiment, the flexible marker material includes one or more metal powders in combinations with parylene, PLGA, POE, PGA, PLLA, PAA, PEG, chitosan and/or derivatives of one or more of these polymers. In another and/or alternative non-limiting embodiment, the flexible marker material includes one or more metals and/or metal powders of aluminum, barium, bismuth, cobalt, copper, chromium, gold, iron, stainless steel, titanium, vanadium, nickel, zirconium, niobium, lead, molybdenum, platinum, yttrium, calcium, rare earth metals, rhenium, zinc, silver, depleted radioactive elements, tantalum and/or tungsten; and/or compounds thereof. The marker material can be coated with a polymer protective material; however, this is not required. When the marker material is coated with a polymer protective material, the polymer coating can be used to 1) at least partially insulate the marker material from body fluids, 2) facilitate in retaining the marker material on the medical device, 3) at least partially shield the marker material from damage during a medical procedure and/or 4) provide a desired surface profile on the medical device. As can be appreciated, the polymer coating can have other or additional uses. The polymer protective coating can be a biostable polymer or a biodegradable polymer (e.g., degrades and/or is absorbed). The coating thickness of the protective coating polymer material, when used, is typically less than about 300 microns; however, other thickness can be used. In one non-limiting embodiment, the protective coating materials include parylene, PLGA, POE, PGA, PLLA, PAA, PEG, chitosan and/or derivatives of one or more of these polymers.
[0029] In a further and/or alternative non-limiting aspect of the present invention, the medical device or one or more regions of the medical device can be constructed by use of one or more microelectromechanical manufacturing techniques (MEMS) (e.g., micro-machining, laser micro-machining, laser micro-machining, micro-molding, etc.); however, other or additional manufacturing techniques can be used. The medical device can include one or more surface structures (e.g., pore, channel, pit, rib, slot, notch, bump, teeth, needle, well, hole, groove, etc.). These structures can be at least partially formed by MEMS (e.g., micro-machining, etc.) technology and/or other types of technology. The medical device can include one or more micro-structures (e.g., micro-needle, micro-pore, micro-cylinder, micro-cone, micro-pyramid, micro-tube, micro-parallelopiped, micro-prism, micro-hemisphere, teeth, rib, ridge, ratchet, hinge, zipper, zip-tie like structure, etc.) on the surface of the medical device. As defined herein, a micro-structure is a structure that has at least one dimension (e.g., average width, average diameter, average height, average length, average depth, etc.) that is no more than about 2 mm, and typically no more than about 1 mm. As can be appreciated, the medical device, when including one or more surface structures, a) all the surface structures can be micro-structures, b) all the surface structures can be non-micro-structures, or c) a portion of the surface structures can be micro-structures and a portion can be non-micro-structures. Non-limiting examples of structures that can be formed on the medical devices such as medical devices are illustrated in United States Patent Publication Nos. 2004/0093076 and 2004/0093077, which are incorporated herein by reference. Typically, the micro-structures, when formed, extend from or into the outer surface no more than about 400 microns, and more typically less than about 300 microns, and more typically about 15-250 microns; however, other sizes can be used. The micro-structures can be clustered together or disbursed throughout the surface of the medical device. Similar shaped and/or sized micro-structures and/or surface structures can be used, or different shaped and/or sized micro-structures can be used. When one or more surface structures and/or micro-structures are designed to extend from the surface of the medical device, the one or more surface structures and/or micro-structures can be formed in the extended position and/or be designed so as to extend from the medical device during and/or after deployment of the medical device in a treatment area. The micro-structures and/or surface structures can be designed to contain and/or be fluidly connected to a passageway, cavity, etc.; however, this is not required. The one or more surface structures and/or micro-structures can be used to engage and/or penetrate surrounding tissue or organs once the medical device has be position on and/or in a patient; however, this is not required. The one or more surface structures and/or micro-structures can be used to facilitate in forming maintaining a shape of a medical device (i.e., see devices in United States Patent Publication Nos. 2004/0093076 and 2004/0093077). The one or more surface structures and/or micro-structures can be at least partially formed by MEMS (e.g., micro-machining, laser micro-machining, micro-molding, etc.) technology; however, this is not required. In one non-limiting embodiment, the one or more surface structures and/or micro-structures can be at least partially formed of an agent and/or be formed of a polymer. One or more of the surface structures and/or micro-structures can include one or more internal passageways that can include one or more materials (e.g., agent, polymer, etc.); however, this is not required. The one or more surface structures and/or micro-structures can be formed by a variety of processes (e.g., machining, chemical modifications, chemical reactions, MEMS (e.g., micro-machining, etc.), etching, laser cutting, etc.). The one or more coatings and/or one or more surface structures and/or micro-structures of the medical device can be used for a variety of purposes such as, but not limited to, 1) increasing the bonding and/or adhesion of one or more agents, adhesives, marker materials and/or polymers to the medical device, 2) changing the appearance or surface characteristics of the medical device, and/or 3) controlling the release rate of one or more agents. The one or more micro-structures and/or surface structures can be biostable, biodegradable, etc. One or more regions of the medical device that are at least partially formed by MEMS techniques can be biostable, biodegradable, etc. The medical device or one or more regions of the medical device can be at least partially covered and/or filled with a protective material so to at least partially protect one or more regions of the medical device, and/or one or more micro-structures and/or surface structures on the medical device from damage. One or more regions of the medical device, and/or one or more micro-structures and/or surface structures on the medical device can be damaged when the medical device is 1) packaged and/or stored, 2) unpackaged, 3) connected to and/or other secured and/or placed on another medical device, 4) inserted into a treatment area, 5) handled by a user, and/or 6) form a barrier between one or more micro-structures and/or surface structures and fluids in various regions of a body. As can be appreciated, the medical device can be damaged in other or additional ways. The protective material can be used to protect the medical device and one or more micro-structures and/or surface structures from such damage. The protective material can include one or more polymers previously identified above. The protective material can be 1) biostable and/or biodegradable and/or 2) porous and/or non-porous. In one non-limiting design, the polymer is at least partially biodegradable so as to at least partially exposed one or more micro-structure and/or surface structure to the environment after the medical device has been at least partially inserted into a treatment area. In another and/or additional non-limiting design, the protective material includes, but is not limited to, sugar (e.g., glucose, fructose, sucrose, etc.), carbohydrate compound, salt (e.g., NaCl, etc.), parylene, PLGA, POE, PGA, PLLA, PAA, PEG, chitosan and/or derivatives of one or more of these materials; however, other and/or additional materials can be used. In still another and/or additional non-limiting design, the thickness of the protective material is generally less than about 300 microns, and typically less than about 150 microns; however, other thicknesses can be used. The protective material can be coated by one or more mechanisms previously described herein.
[0030] In still yet another and/or alternative non-limiting aspect of the present invention, the medical device can include and/or be used with a physical hindrance. The physical hindrance can include, but is not limited to, an adhesive, a sheath, a magnet, tape, wire, string, etc. The physical hindrance can be used to 1) physically retain one or more regions of the medical device in a particular form or profile, 2) physically retain the medical device on a particular deployment device, 3) protect one or more surface structures and/or micro-structures on the medical device, and/or 4) form a barrier between one or more surface regions, surface structures and/or micro-structures on the medical device and the fluids in various regions of a body. As can be appreciated, the physical hindrance can have other and/or additional functions. The physical hindrance is typically a biodegradable material; however, a biostable material can be used. The physical hindrance can be designed to withstand sterilization of the medical device; however, this is not required. The physical hindrance can be applied to, included in and/or be used in conjunction with one or more medical devices. Additionally or alternatively, the physical hindrance can be designed to be used with and/or conjunction with a medical device for a limited period of time and then 1) disengage from the medical device after the medical device has been partially or fully deployed and/or 2) dissolve and/or degrade during and/or after the medical device has been partially or fully deployed; however, this is not required. Additionally or alternatively, the physical hindrance can be designed and be formulated to be temporarily used with a medical device to facilitate in the deployment of the medical device; however, this is not required. In one non-limiting use of the physical hindrance, the physical hindrance is designed or formulated to at least partially secure a medical device to another device that is used to at least partially transport the medical device to a location for treatment. In another and/or alternative non-limiting use of the physical hindrance, the physical hindrance is designed or formulated to at least partially maintain the medical device in a particular shape or form until the medical device is at least partially positioned in a treatment location. In still another and/or alternative non-limiting use of the physical hindrance, the physical hindrance is designed or formulated to at least partially maintain and/or secure one type of medical device to another type of medical instrument or device until the medical device is at least partially positioned in a treatment location. The physical hindrance can also or alternatively be designed and formulated to be used with a medical device to facilitate in the use of the medical device. In one non-limiting use of the physical hindrance, when in the form of an adhesive, can be formulated to at least partially secure a medical device to a treatment area so as to facilitate in maintaining the medical device at the treatment area. For instance, the physical hindrance can be used in such use to facilitate in maintaining a medical device on or at a treatment area until the medical device is properly secured to the treatment area by sutures, stitches, screws, nails, rod, etc.; however, this is not required. Additionally or alternatively, the physical hindrance can be used to facilitate in maintaining a medical device on or at a treatment area until the medical device has partially or fully accomplished its objective. The physical hindrance is typically a biocompatible material so as to not cause unanticipated adverse effects when properly used. The physical hindrance can be biostable or biodegradable (e.g., degrades and/or is absorbed, etc.). When the physical hindrance includes or has one or more adhesives, the one or more adhesives can be applied to the medical device by, but is not limited to, spraying (e.g., atomizing spray techniques, etc.), dip coating, roll coating, sonication, brushing, plasma deposition, and/or depositing by vapor deposition, brushing, painting, etc.) on the medical device. The physical hindrance can also or alternatively form at least a part of the medical device. One or more regions and/or surfaces of a medical device can also or alternatively include the physical hindrance. The physical hindrance can include one or more biological agents and/or other materials (e.g., marker material, polymer, etc.); however, this is not required. When the physical hindrance is or includes an adhesive, the adhesive can be formulated to controllably release one or more biological agents in the adhesive and/or coated on and/or contained within the medical device; however, this is not required. The adhesive can also or alternatively control the release of one or more biological agents located on and/or contained in the medical device by forming a penetrable or non-penetrable barrier to such biological agents; however, this is not required. The adhesive can include and/or be mixed with one or more polymers; however, this is not required. The one or more polymers can be used to 1) control the time of adhesion provided by said adhesive, 2) control the rate of degradation of the adhesive, and/or 3) control the rate of release of one or more biological agents from the adhesive and/or diffusing or penetrating through the adhesive layer; however, this is not required. When the physical hindrance includes a sheath, the sheath can be designed to partially or fully encircle the medical device. The sheath can be designed to be physically removed from the medical device after the medical device is deployed to a treatment area; however, this is not required. The sheath can be formed of a biodegradable material that at least partially degrades over time to at least partially expose one or more surface regions, micro-structures and/or surface structures of the medical device; however, this is not required. The sheath can include and/or be at least partially coated with one or more biological agents. The sheath includes one or more polymers; however, this is not required. The one or more polymers can be used for a variety of reasons such as, but not limited to, 1) forming a portion of the sheath, 2) improving a physical property of the sheath (e.g., improve strength, improve durability, improve biocompatibility, reduce friction, etc.), and/or 3 at least partially controlling a release rate of one or more biological agents from the sheath. As can be appreciated, the one or more polymers can have other or additional uses on the sheath.
[0031] In another and/or alternative non-limiting aspect of the invention, the medical device can include a biostable construction. In such a design, the medical device has two or more stable configurations, including a first stable configuration with a first cross-sectional shape and a second stable configuration with a second cross-sectional shape. All or a portion of the medical device can include the biostable construction. The bistable construction can result in a generally uniform change in shape of the medical device, or one portion of the medical device can change into one or more configurations and one or more other portions of the medical device can change into one or more other configurations.
[0032] In still another and/or alternative aspect of the invention, the medical device can be an expandable device that can be expanded by use of some other device (e.g., balloon, etc.) and/or is self-expanding. The expandable medical device can be fabricated from a material that has no or substantially no shape memory characteristics or can be partially fabricated from a material having shape-memory characteristics. Typically, when one or more shape-memory materials are used, the shape-memory material composition is selected such that the shape-memory material remains in an unexpanded configuration at a cold temperature (e.g., below body temperature); however, this is not required. When the shape-memory material is heated (e.g., to body temperature) the expandable body section can be designed to expand to at least partially seal and secure the medical device in various regions of a body; however, this is not required.
[0033] In still another and/or alternative non-limiting aspect of the invention, the medical device can be used in conjunction with one or more other biological agents that are not on the medical device. For instance, the success of the medical device can be improved by infusing, injecting or consuming orally one or more biological agents. Such biological agents can be the same and/or different from the one or more biological agents on and/or in the medical device. Such use of one or more biological agents are commonly used in systemic treatment of a patient after a medical procedure such as body wide after the medical device has been inserted in the treatment area can be reduced or eliminated by use of the novel alloy. Although the medical device of the present invention can be designed to reduce or eliminate the need for long periods of body-wide therapy after the medical device has been inserted in the treatment area, the use of one or more biological agents can be used in conjunction with the medical device to enhance the success of the medical device and/or reduce or prevent the occurrence of one or more biological problems (e.g., infection, rejection of the medical device, etc.). For instance, solid dosage forms of biological agents for oral administration, and/or for other types of administration (e.g., suppositories, etc.) can be used. Such solid forms can include, but are not limited to, capsules, tablets, effervescent tablets, chewable tablets, pills, powders, sachets, granules and gels. The solid form of the capsules, tablets, effervescent tablets, chewable tablets, pills, etc. can have a variety of shapes such as, but not limited to, spherical, cubical, cylindrical, pyramidal, and the like. In such solid dosage form, one or more biological agents can be admixed with at least one filler material such as, but not limited to, sucrose, lactose or starch; however, this is not required. Such dosage forms can include additional substances such as, but not limited to, inert diluents (e.g., lubricating agents, etc.). When capsules, tablets, effervescent tablets or pills are used, the dosage form can also include buffering agents; however, this is not required. Soft gelatin capsules can be prepared to contain a mixture of the one or more biological agents in combination with vegetable oil or other types of oil; however, this is not required. Hard gelatin capsules can contain granules of the one or more biological agents in combination with a solid carrier such as, but not limited to, lactose, potato starch, corn starch, cellulose derivatives of gelatin, etc.; however, this is not required. Tablets and pills can be prepared with enteric coatings for additional time release characteristics; however, this is not required. Liquid dosage forms of the one or more biological agents for oral administration can include pharmaceutically acceptable emulsions, solutions, suspensions, syrups, elixirs, etc.; however, this is not required. In one non-limiting embodiment, when at least a portion of one or more biological agents is inserted into a treatment area (e.g., gel form, paste form, etc.) and/or provided orally (e.g., pill, capsule, etc.) and/or anally (suppository, etc.), one or more of the biological agents can be controllably released; however, this is not required. In one non-limiting example, one or more biological agents can be given to a patient in solid dosage form and one or more of such biological agents can be controllably released from such solid dosage forms. In another and/or alternative non-limiting example trapidil, trapidil derivatives, taxol, taxol derivatives, cytochalasin, cytochalasin derivatives, paclitaxel, paclitaxel derivatives, rapamycin, rapamycin derivatives, 5-Phenylmethimazole, 5-Phenylmethimazole derivatives, GM-CSF, GM-CSF derivatives, or combinations thereof are given to a patient prior to, during and/or after the insertion of the medical device in a treatment area. As can be appreciated, other or additional biological agents can be used. Certain types of biological agents may be desirable to be present in a treated area for an extended period of time in order to utilize the full or nearly full clinical potential the biological agent. For instance, trapidil and/or trapidil derivatives is a compound that has many clinical attributes including, but not limited to, anti-platelet effects, inhibition of smooth muscle cells and monocytes, fibroblast proliferation and increased MAPK-1 which in turn deactivates kinase, a vasodilator, etc. These attributes can be effective in improving the success of a medical device that has been inserted at a treatment area. In some situations, these positive effects of trapidil and/or trapidil derivatives need to be prolonged in a treatment area in order to achieve complete clinical competency. Trapidil and/or trapidil derivatives have a half-life in vivo of about 2-4 hours with hepatic clearance of 48 hours. In order to utilize the full clinical potential of trapidil and/or trapidil derivatives, trapidil and/or trapidil derivatives should be metabolized over an extended period of time without interruption; however, this is not required. By inserting trapidil and/or trapidil derivatives in a solid dosage form, the trapidil and/or trapidil derivatives could be released in a patient over extended periods of time in a controlled manner to achieve complete or nearly complete clinical competency of the trapidil and/or trapidil derivatives. In another and/or alternative non-limiting example, one or more biological agents are at least partially encapsulated in one or more polymers. The one or more polymers can be biodegradable, non-biodegradable, porous, and/or non-porous. When the one or more polymers are biodegradable, the rate of degradation of the one or more biodegradable polymers can be used to at least partially control the rate at which one or more biological agents that are released into various regions of a body and/or other parts of the body over time. The one or more biological agents can be at least partially encapsulated with different polymer coating thickness, different numbers of coating layers, and/or with different polymers to alter the rate at which one or more biological agents are released in various regions of a body over time. The rate of degradation of the polymer is principally a function of 1) the water permeability and solubility of the polymer, 2) chemical composition of the polymer and/or biological agent, 3) mechanism of hydrolysis of the polymer, 4) the biological agent encapsulated in the polymer, 5) the size, shape and surface volume of the polymer, 6) the porosity of the polymer, 7) the molecular weight of the polymer, 8) the degree of cross-linking in the polymer, 9) the degree of chemical bonding between the polymer and biological agent, and/or 10) the structure of the polymer and/or biological agent. As can be appreciated, other factors may also affect the rate of degradation of the polymer. When the one or more polymers are biostable, the rate at when the one or more biological agents are released from the biostable polymer is a function of 1) the porosity of the polymer, 2) the molecular diffusion rate of the biological agent through the polymer, 3) the degree of cross-linking in the polymer, 4) the degree of chemical bonding between the polymer and biological agent, 5) chemical composition of the polymer and/or biological agent, 6) the biological agent encapsulated in the polymer, 7) the size, shape and surface volume of the polymer, and/or 8) the structure of the polymer and/or biological agent. As can be appreciated, other factors may also affect the rate of release of the one or more biological agents from the biostable polymer. Many different polymers can be used such as, but not limited to, aliphatic polyester compounds (e.g., PLA (i.e. poly(D, L-lactic acid), poly(L-lactic acid)), PLGA (i.e. poly(lactide-co-glycoside), etc.), POE, PEG, PLLA, parylene, chitosan and/or derivatives thereof As can be appreciated, the at least partially encapsulated biological agent can be introduced into a patient by means other than by oral introduction, such as, but not limited to, injection, topical applications, intravenously, eye drops, nasal spray, surgical insertion, suppositories, intrarticularly, intraocularly, intranasally, intradermally, sublingually, intravesically, intrathecally, intraperitoneally, intracranially, intramuscularly, subcutaneously, directly at a particular site, and the like.
[0034] The use of the novel metal alloy to form all or a portion of the medical device can result in several advantages over medical devices formed from other materials. These advantages include, but are not limited to:
[0035] The novel metal alloy has increased strength as compared with stainless steel or chromium-cobalt alloys, thus less quantity of novel metal alloy can be used in the medical device to achieve similar strengths as compared to medical devices formed of different metals. As such, the resulting medical device can be made smaller and less bulky by use of the novel metal alloy without sacrificing the strength and durability of the medical device. The medical device can also have a smaller profile, thus can be inserted into smaller areas, openings and/or passageways. The increased strength of the novel metal alloy also results in the increased radial strength of the medical device. For instance, the thickness of the walls of the medical device and/or the wires used to form the medical device can be made thinner and achieve a similar or improved radial strength as compared with thicker walled medical devices formed of stainless steel or cobalt and chromium alloy.
[0036] The novel metal alloy has improved stress-strain properties, bendability properties, elongation properties and/or flexibility properties of the medical device as compared with stainless steel or chromium-cobalt alloys, thus resulting in an increase life for the medical device. For instance, the medical device can be used in regions that subject the medical device to repeated bending. Due to the improved physical properties of the medical device from the novel metal alloy, the medical device has improved resistance to fracturing in such frequent bending environments. These improved physical properties at least in part result from the composition of the novel metal alloy; the grain size of the novel metal alloy; the carbon, oxygen and nitrogen content of the novel metal alloy; and/or the carbon/oxygen ratio of the novel metal alloy.
[0037] The novel metal alloy has a reduced degree of recoil during the crimping and/or expansion of the medical device as compared with stainless steel or chromium-cobalt alloys. The medical device formed of the novel metal alloy better maintains its crimped form and/or better maintains its expanded form after expansion due to the use of the novel metal alloy. As such, when the medical device is to be mounted onto a delivery device when the medical device is crimped, the medical device better maintains its smaller profile during the insertion of the medical device in various regions of a body. Also, the medical device better maintains its expanded profile after expansion so as to facilitate in the success of the medical device in the treatment area.
[0038] The novel metal alloy has improved radiopaque properties as compared to standard materials such as stainless steel or cobalt-chromium alloy, thus reducing or eliminating the need for using marker materials on the medical device. For instance, the novel metal alloy is at least about 10-20% more radiopaque than stainless steel or cobalt-chromium alloy.
[0039] The novel metal alloy is less of an irritant to the body than stainless steel or cobalt-chromium alloy, thus can result in reduced inflammation, faster healing, and increased success rates of the medical device.
[0040] One non-limiting object of the present invention is the provision of a medical device that is at least partially formed of a novel metal alloy.
[0041] Another and/or alternative non-limiting object of the present invention is the provision of a medical device having improved procedural success rates.
[0042] Still another and/or alternative non-limiting object of the present invention is the provision of a medical device that is in the form of a dental implant. The dental implant for insertion into bone generally includes an implant anchor having a connection arrangement (e.g., an interlocking thread, etc.). The dental implant can include a plurality of keys disposed about the distal end of the abutment, which distal end is capable of being affixed to the prosthetic tooth or dental appliance; an implantable anchor having a proximal and distal end, a plurality of female keyways defined into the proximal end of the anchor, the keyways capable of coupling to the male keys of the abutment and thereby preventing relative rotation of the abutment and anchor; however, this is not required. The dental implant can optionally include a repository bore perpendicular to the longitudinal bore defined in a distal portion of the anchor. The repository bore is cut through a portion of the anchor creating very sharp cutting edges to become self-tapping. The repository bore also can optionally serve as a repository for the bone chips created during the thread cutting process. One non-limiting dental implant is described in U.S. Pat. No. 7,198,488, which is incorporated herein by reference. The dental implant has a cylindrical anchoring head formed unitarily with a screw element. The screw element, usually made of the metal alloy of the present invention or titanium with a roughened surface, and is to be screwed into the recipient jaw bone. The anchoring head which can be formed of the metal alloy of the present invention is adapted to have a prosthetic tooth mounted on it.
[0043] Still another and/or alternative non-limiting object of the present invention is the provision of a medical device that is formed of a material that improves the physical properties of the medical device.
[0044] Yet another and/or alternative non-limiting object of the present invention is the provision of a medical device that is at least partially formed of a novel metal alloy that has increased strength and can also be used as a marker material.
[0045] Still yet another and/or alternative non-limiting object of the present invention is the provision of a medical device that at least partially includes a novel metal alloy that enables the medical device to be formed with less material without sacrificing the strength of the medical device as compared to prior medical devices.
[0046] Still yet another and/or alternative non-limiting object of the present invention is the provision of a medical device that is simple and cost effective to manufacture.
[0047] A further and/or alternative non-limiting object of the present invention is the provision of a medical device that is at least partially coated with one or more polymer coatings.
[0048] Still a further and/or alternative non-limiting object of the present invention is the provision of a medical device that is coated with one or more biological agents.
[0049] Yet a further and/or alternative non-limiting object of the present invention is the provision of a medical device that has one or more polymer coatings to at least partially control the release rate of one or more biological agents.
[0050] Still yet a further and/or alternative non-limiting object of the present invention is the provision of a medical device that includes one or more surface structures and/or micro-structures.
[0051] Still a further and/or alternative non-limiting object of the present invention is the provision of a method and process for forming a novel metal alloy into a medical device.
[0052] Another and/or alternative non-limiting object of the present invention is the provision of a medical device that includes one or more surface structures, micro-structures and/or internal structures and a protective coating that at least partially covers and/or protects such structures.
[0053] Yet another and/or alternative non-limiting object of the present invention is the provision of a medical device that includes one or more markers.
[0054] Still another and/or alternative non-limiting object of the present invention is the provision of a medical device that includes and/or is used with one or more physical hindrances.
[0055] Still yet another and/or alternative non-limiting object of the present invention is the provision of a medical device that can be used in conjunction with one or more biological agents not on or in the medical device.
[0056] A further and/or alternative non-limiting object of the present invention is the provision of a method and process for forming a novel metal alloy that inhibits or prevent the formation of micro-cracks during the processing of the alloy into a medical device.
[0057] Still a further and/or alternative non-limiting object of the present invention is the provision of a method and process for forming a novel metal alloy that inhibits or prevents in the introduction of impurities into the alloy during the processing of the alloy into a medical device.
[0058] These and other advantages will become apparent to those skilled in the art upon the reading and following of this description.
DESCRIPTION OF THE DRAWING
[0059] Reference may now be made to the drawings, which illustrate various embodiments that the invention may take in physical form and in certain parts and arrangements of parts wherein:
[0060] FIG. 1 is a longitudinal axial section through a dental implant.
DETAILED DESCRIPTION OF THE INVENTION
[0061] Referring now to the drawing wherein the showings are for the purpose of illustrating an embodiment of the invention only and not for the purpose of limiting the same, FIG. 1 illustrates a dental implant that includes an anchoring head which in its outer contour is cylindrical and formed in one piece with a screw element extending in an apical direction. The anchoring head has an anchoring area which is coaxial with the longitudinal axis and is formed with an internal set of teeth which serve for engagement in a form fitting manner with an implanting tool or element capable of rotatably driving the implant and for the engagement with the end which can be plugged into the implant of a superstructure or other element to be mounted thereon. The internal teeth terminate in the apical direction at a blind bore with an internal screw thread into which the anchoring screw of the superstructure can be threaded to mount the structure on the implant. While the internal teeth extend substantially over the entire length of the anchoring head, the blind bore occupies a fraction of the length of the screw element. As can be seen in FIG. 1 , the screw element has a thread core and a self-cutting external thread. In the direction of the longitudinal axis, the thread core and the outer thread are subdivided into a plurality of segments following one another from the crestal to the apical, and of which the first crestal segment adjoins the anchoring head. In this segment, the outer thread has a constant outer diameter which corresponds to the outer diameter of the anchoring head. The thread core runs in this segment tapering in the apical direction and diminishes from a diameter. The thread core thus merges steplessly into the outer surface of the anchoring head. The diameter reduction of the thread core in the segment continues to an intermediate diameter which is less than the outer diameter of the anchoring head. The middle segment adjoins the crestal segment and in this middle segment the outer diameter of the outer thread and the outer diameter of the core may remain constant; however, this is not required. The apparent reduction of the outer diameter in the middle segment is a result of the longitudinal grooves shown in the section of FIG. 1 . In the third point or tip segment, both the outer thread and the thread core taper in the apical direction. As also will be apparent from FIG. 1 , beginning at the middle segment on two diametrically opposite sides of the screw element, two parallel longitudinal grooves are provided which run parallel to the longitudinal axis.
[0062] It will thus be seen that the objects set forth above, among those made apparent from the preceding description, are efficiently attained, and since certain changes may be made in the constructions set forth without departing from the spirit and scope of the invention, it is intended that all matter contained in the above description and shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense. The invention has been described with reference to preferred and alternate embodiments. Modifications and alterations will become apparent to those skilled in the art upon reading and understanding the detailed discussion of the invention provided herein. This invention is intended to include all such modifications and alterations insofar as they come within the scope of the present invention. It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described and all statements of the scope of the invention, which, as a matter of language, might be said to fall therebetween. | A dental implant comprising an anchoring head, a screw element connected to the anchoring head, and a prosthetic tooth that is connectable to said anchoring head, said anchoring head formed of a metal alloy. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates generally to mechanical devices for use with hangers provided with clamping members. More specifically, the invention relates to an apparatus for automatically opening and closing the clamping members of flexible skirt hangers.
2. Description of the Prior Art
Garment manufacturers have for many years utilized flexible or pliable clothing hangers to hang clothes after manufacture, and during shipment to customers. The significant variety of hangers available in the prior art may be characterized as either clamping or non-clamping hangers.
Clamping hangers are those provided with means thereon for actively clamping or gripping clothing hung on the hanger. Clamping hangers, as the term is used herein, generally incorporate two clamping members which are normally in equilibrium in a closed position and must be separated or opened from said closed position to enable a garment (or garments) to be inserted between the clamping members which are then allowed to resume, or tend to resume their equilibrium position.
As is well known to those skilled in the art, depending on the construction of the hangers, the clamping members may be urged together in their equilibrium position by spring force means or may be maintained in said equilibrium position by an absence of forces urging them together. In either case, opening the clamping members necessitates applying a force to each clamping member greater than the equilibrium force. Removal of this opening force creates an imbalance whereby the inherent resiliency of the clamping members causes them to close toward the equilibrium position. Obviously, if a garment is inserted between the clamping members they will not be able to return to the equilibrium position (depending upon the thickness of the garment), but will tend to return to that position. The tension created between the clamping members as they tend to resume equilibrium serves to hold the garment therebetween (generally aided by projections on the clamping members).
Non-clamping hangers do not have clamping members and are utilized by merely draping the clothing thereon.
While several different types of clamping hangers are utilized throughout the garment industry, one of the most widely used is a flexible clamping hanger known as a plastic skirt hanger R-8 or R-11 (depending upon size) manufactured by Mr. Hanger, Inc., 20 Jones St., New Rochelle, N.Y. (as well as others). This type of hanger is made of plastic or similar flexible material in a one-piece molded configuration, and has the general appearance of a planar rectangle open along one long side with the hook attached to the other long side (best seen in FIGS. 3A and 3B below). Each short side of this rectangle has paired clamping members molded into it which, in this configuration, comprise a tongue and a tongue frame surrounding the tongue on three sides, the base of the tongue being molded into the skirt hanger and the tongue extending in a direction opposite that of the hook. The tongue and tongue frame clamping members of this type of skirt hanger are normally in equilibrium when nothing is inserted therebetween. As the clamping members are bent or moved apart by a user away from their equilibrium position, thus opening the tongue, the inherent resiliency of the material of which this hanger is made creates forces between a tongue and its corresponding tongue frame, urging them together again. Upon allowing the tongue to tend to resume its normal, equilibrium position, any garment inserted between the tongue and its corresponding tongue frame will be retained by the tension created by the garment being interwoven between said tongue and its corresponding tongue frame. Projections may be molded into the tongues and tongue frames to enhance their ability to hold garments.
No prior art device is known for automatically opening the tongues of such flexible skirt hangers. Accordingly, such skirt hangers have always been used manually to the disadvantage of garment manufacturers and others. The manual use of this type of hanger requires a user to proceed through several time consuming and inefficient manual operations in order to complete the task of securing a garment to the hanger. For example, the user must: (1) get one hanger; (2) place it on a working surface; (3) get the garment to be hung on the hanger; (4) open a first tongue of the hanger with one hand while inserting one side of the garment between the first tongue and its corresponding tongue frame; (5) release the first tongue; (6) open the other, second tongue of the hanger with one hand while inserting the other side of the garment between the second tongue and its corresponding tongue frame; (7) release the second tongue and (8) place the hanger with garment on a rack or other collecting spot. This manual labor requires a considerable amount of time and is therefore inefficient and expensive. Accordingly, it is an object of this invention to provide an apparatus for automatically opening and closing the clamping members of a flexible skirt hanger.
It is a further object of this invention to provide an apparatus for automatically feeding one hanger at a time to a work station where a user may utilize it to hang a garment thereon.
It is yet another object of this invention to provide an apparatus for automatically opening the clamping members of a flexible skirt hanger, enabling a user to insert a garment therebetween, and subsequently closing said clamping members, all operations capable of being performed without the necessity of the user manipulating said clamping members.
SUMMARY OF THE INVENTION
These and other objects of the present invention are achieved by the preferred embodiment disclosed herein. The preferred embodiment selectively and automatically opens and closes the tongues of a flexible skirt hanger as the latter is held at a work station in a frame which limits movement in a first direction of each tongue frame, while enabling movement in a second direction of the base area of each tongue, said second direction being substantially opposite said first direction. Such movement, in conjunction with a pivot point intermediate said base and the tip or end of said tongue frame, imparts a twisting effect to the clamping members of the hanger causing the tongue bases and the tongue frame tips to be urged in the same direction which causes the tongues to open in the opposite direction. The activating mechanism which causes the tongues to open consists of a plunger or rod which is pneumatically extended to move the base of each tongue in said second direction. The invention also includes means for automatically feeding a hanger to said work station.
BRIEF DESCRIPTION OF THE DRAWINGS
A better understanding of the present invention as well as additional objects and advantages thereof will become apparent upon consideration of the detailed disclosure thereof which follows, in conjunction with the following drawings, wherein:
FIG. 1 is a side elevational diagrammatic view, partly in a cross-section, of the preferred embodiment of the invention;
FIG. 2 is a front elevational view of FIG. 1 taken along the line 2--2;
FIG. 3A is a plan view of the front of a skirt hanger for use with the preferred embodiment;
FIG. 3B is a plan view of the back of the hanger shown in FIG. 3A;
FIG. 4 is a side elevational view of the hanger shown in FIG. 3A taken along the lines 4--4;
FIG. 5 is a side elevational view of the hanger shown in FIG. 3A showing the tongue in an open position;
FIG. 6 is a view of FIG. 2 showing the hanger of FIGS. 3A and 3B at rest at the work station of the preferred embodiment;
FIG. 7 is a view of FIG. 1 showing the hanger of FIGS. 3A and 3B in the work station in the tongue-open position;
FIG. 8 is a schematic diagram of the pneumatic control system utilized in the preferred embodiment;
FIG. 9 is a timing diagram showing the sequence of events in the preferred embodiment.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to FIG. 1, there is shown a side elevational view, partly cross-sectional, of the preferred embodiment of the present invention, generally designated as apparatus 10.
Apparatus 10 includes a work portion 12 and an automatic feeding portion or feeder 14. Work portion 12 is more clearly seen in FIG. 2 which is a front elevational view of FIG. 1 taken along the lines 2--2. Apparatus 10 includes a frame 16 for supporting feeder 14, a frame 18 for supporting work station 12 and a base 20 for holding frames 16 and 18 together in a predetermined orientation. An understanding of the present invention may best be obtained by sequentially describing the operation of the various elements of the invention as it performs its intended function of opening and closing the clamping members of a flexible skirt hanger.
Initially, a plurality of skirt hangers 22 is retained on inclined hanger stacking rods 24 and 25. Hanger 22 is relatively thin and substantially planar as is shown in FIGS. 3A, 3B and 4 and includes a hook 26, crossbar 30, left and right tongue frames 32 and 34, respectively, and left and right tongues 33 and 35, respectively associated therewith. Hook 26 and crossbar 30 generally identify the top 38 of hanger 22, and the left and right tongue tips 42 and 44 respectively, along with the left and right tongue frame tip portions 46 and 48 respectively, generally identify the bottom 50 of hanger 22. Each tongue tip is situated at a distance 45 from the farthest point of its respective tongue frame.
Hanger 22 is generally constructed of one-piece, molded pliable plastic or other similarly flexible material and is sufficiently flexible to enable tongue tips 42 and 44 to be bent away from respective tongue frame tips 46 and 48 as is best seen in FIG. 5, thus creating a space 51 therebetween for the insertion of clothing or other material to be hung on the hanger. Tongues and tongue frames may have projections 31 and 36, respectively, molded therein to enhance the gripping operation thereof. Tongues 33 and 35 have base areas 52 and 54 respectively where the tongues join crossbar 30.
For clarity, FIGS. 1 and 2 depict only one such hanger 23 in phantom (identical to hangers 22 but differentiated therefrom by being the hanger to slide past feeder 14 in any one cycle) supported by rods 24 and 25, but it will be understood that a plurality of similar hangers may be supported (in storage) behind hanger 23, extending upwardly along rods 24 and 25. Rods 24 and 25 are inclined sufficiently to cause hangers 22 to slide downwardly thereon in response to gravitational forces. Hangers 22 are inhibited in their slide along rods 24 and 25 by stop member 60 and retaining spring 62 which cooperate to hold back all hangers 22 while selectively permitting hanger 23 to slide past stop member 60.
Stop member 60 is held in the raised position shown in FIG. 2 by a spring (not shown) and may be depressed by plunger or rod 64 in order to permit one hanger (23) to slide past stop member 60. Rod 64 is activated by a double-action air cylinder 66 (by pneumatic means more fully explained below) which selectively causes rod 64 to be extended sufficiently to depress stop member 60 and subsequently to be retracted to allow member 60 to rise to assist spring 62 in holding the remaining hangers 22 stacked on rods 24 and 25.
After being released by stop member 60, hanger 23 will slide to and off the bottom end 68 of rods 24 and 25 and will hit stop plate 70 which is oriented generally perpendicular to rods 24 and 25. Hanger 23 will hit the back 72 of stop plate 70 and slide downwardly thereon until it hits slide ramp 74 along approximately the line of intersection (not shown) of slide ramp 74 and the plane of stop plate 70. Slide ramp 74 and stop plate 70 are separated by space 80 having a predetermined size sufficient to let hanger 23 pass therethrough, as will be more fully explained below.
The inertia of hanger 23 prior to its impact with slide ramp 74 causes hanger 23 to fall away from back surface 72 and on to spring steel plate 76 attached to the top end of slide ramp 74. Also, space 80 is sufficiently large to facilitate hanger 23 falling away from back surface 72. That is, as hanger 23 falls on to slide ramp 74 the tongue frame tips 46 and 48 are the first parts of the hanger to touch the ramp. Hanger 23 momentarily stays in this position (with only tips 46 and 48 touching ramp 74 and a certain portion of hanger 23 remaining against back surface 72) until the weight of bottom portion 50 of hanger 23 causes tips 46 and 48 to start to fall through space 80. Spring 76 serves to "bounce" the hook 26 and top end 38 of hanger 23 upwardly (after hanger 23 falls) thereby causing the bottom end 50 of hanger 23 to move downwardly to assure that bottom end 50 will easily pass through space 80 and under lip 112 as will be understood below. Left and right lateral brackets 81 and 82 serve to limit the lateral motion of hanger 23 to facilitate its subsequent positioning as will be understood below. As hanger 23 slides downwardly along slide ramp 74 it will pass toward work portion 12, the configuration of which may best be understood by reference to FIG. 2.
Hanger 23 slides down slide ramp 74 and onto work station ramp 100 aligned therewith and spaced apart therefrom by a predetermined distance 103 to form aperture 104 therebetween. Ramps 74 and 100 are held together in proper spatial relationship by left and right lateral guides 101 and 102, respectively, which are raised above the surfaces of ramps 74 and 100 to enable the guides to also serve to maintain hanger 23 within a predetermined area in order to position hanger 23 into a work station, as will be more fully explained below. Ramp 100 is provided with left and right grooves or channels, 106 and 108 respectively. These channels are positioned so as to enable hanger 23 to slide smoothly from ramp 74 to ramp 100 in the event tongues 33 and 35 have projections 31 thereon as shown in FIGS. 4 and 5. Such projections might, without use of channels 106 and 108, hit the top edge 105 of ramp 100 (as hanger 23 slides down) which might either stop the downward slide of hanger 23 or cause bottom end 50 of hanger 23 to bounce upwardly which may in turn prevent hanger 23 from coming to rest against stop surface 110 (as will be understood more clearly below).
As hanger 23 slides down ramp 74 its downward slide will be stopped by stop surface 110 which is perpendicular to ramp 100. Retaining lip 112 extends upwardly from stop surface 110 and parallel to ramp 100. Lip 112 has a predetermined width 114 which, as will be more fully understood below, must be less than distance 45. As hanger 23 comes to rest against surface 110, as shown in FIGS. 6 and 7, the tip portions of the tongue frame will rest behind lip 112. The position at which hanger 23 comes to rest as shown in FIG. 6 may be termed work station 115 since additional operations will be performed upon hanger 23 by apparatus 10 while hanger 23 is held in work station 115. These additional operations and the elements of the invention performing same are explained below.
As shown in FIGS. 1 and 2, single action air cylinders 121 and 123 are secured in a predetermined orientation to frame 18 and stop plate 70 by suitable brackets 124 and 125 respectively. After hanger 23 comes to rest at work station 115 and against stop surface 110, rod plungers 120 and 122 of cylinders 121 and 123 respectively, will be situated over tongue base portions 52 and 54 respectively (as best seen in FIGS. 6 and 7). Upon selective activation of cylinders 121 and 123, rods 120 and 122 will be extended a predetermined distance in direction 130 and will cause base portions 52 and 54 and crossbar 30 respectively to move in first direction 130 a predetermined amount. This action will necessarily urge hanger 23 to pivot clockwise (as viewed) on ramp 100 since aperture 104 does not inhibit motion of crossbar 30. However, lip 112, by virtue of its size, resists such pivoting of the tongue frame tip portions 46 and 48 while not inhibiting the clockwise motion of tongues 33 and 35. Lip 112 essentially exerts a force upon tongue frame tips 46 and 48 in second direction 113 (as seen in FIG. 7) which is substantially parallel to direction 130. Pivot edge 105 essentially exerts a force on the tongue frames in a third direction 131 substantially opposite directions 113 and 130. Consequently, a twisting effect will be imparted to each pair of clamping members causing tongues 33 and 35 to open from their respective tongue frames 46 and 48, thereby enabling a user to insert a garment between each respective pair of these clamping members. Front apron 170 facilitates guiding a garment into the opening between the clamping members.
Referring again to FIGS. 1, 2, 6 and 7 there are shown slits 150 having a bent tab 152 therebetween. Bent tab 152 enables movement of hook 26 into the area that would have been occupied by the tab had it not been bent, thus enabling hanger 23 to be bent sufficiently to open the tongues, as will be more fully understood below. Furthermore, cut-out aperture 156 is also provided in stop plate 70 in order to facilitate removal of hanger 23 from work station 115 by not impeding movement of hook 26 by a user.
Cylinders 121 and 123 are purely conventional single action pneumatically driven air cylinders which pneumatically extend rods 120 and 122 and subsequently retract same by means of springs (not shown) when the pneumatic excitation is removed. Those skilled in the art will realize that double action air cylinders may be used if desired, thus effecting a more positive retraction of the rods. In the preferred embodiment disclosed herein the retraction of rods 120 and 122 removes the twisting forces imparted to the pairs of clamping members and enables tongues 33 and 35 to resume their natural tendency toward equilibrium adjacent their respective tongue frames. This action introduces tension in any garment inserted between the clamping members which secures the garment to hanger 23 in a manner well known to those skilled in the art.
Air cylinders 66, 121 and 123 are all activated by a pneumatic control system schematically shown in FIG. 8 and designated 200. Pneumatic system 200 is a combination of conventional pneumatic devices arranged in a manner which will cause said air cylinders to be activated in a predetermined sequence. (For clarity, the pneumatic lines connecting various elements are omitted from the Figures). An understanding of the operation of pneumatic system 200 may best be obtained by describing one cycle of operation which is initiated by depression of starting lever 201.
When starting lever 201 (also seen in FIGS. 1 and 6) is activated by a user, pneumatic line 202 is pressurized causing the spools (not shown) in the sequence control valve 204 to shift in a manner well known to those skilled in the art. This action allows line 206 to exhaust through sequence control valve 204 which in turn permits the spools (not shown) in the 4-way valve 208 to shift thereby exhausting line 210 through the 4-way valve 208. This action causes the spring return rods 120 and 122 to retract.
When rods 120 and 122 are fully retracted, the spools in sequence control valve 204 again shift exhausting line 212 and pressurizing line 214. This action causes the double acting cylinder 66 to retract, thereby permitting one hanger to slide along rods 24 and 25 toward work portion 12.
When cylinder 66 is fully retracted, the spools in sequence control valve 204 shift, exhausting line 214 and pressurizing line 212 thereby forcing double acting cylinder 66 to extend, thereby preventing any more hangers from sliding down rods 24 and 25.
When double acting cylinder 66 is fully extended, the spools in sequence control valve 204 against shift pressurizing line 206 to the pilot actuator 216 of 4-way valve 208, shifting the spools therein. This in turn pressurizes line 210 which extends the spring return rods 120 and 122. When rods 120 and 122 are fully extended the spools in sequence control valve 204 are again shifted directing the air flow to line 220 back to the lever activated 2-way valve 203 which completes the cycle.
Two-way toggle valve 230 and the 2-way lever 232 are similar to valve 203 and are primarily safety devices. When 2-way toggle valve 230 is in the "on" position the operation proceeds as above. When valve 230 is in the "hold" position spring return rods 120 and 122 are retracted and held in the retracted position for the purpose of clearing any hanger which may have jammed. After the device is cleared 2-way toggle valve 230 may be switched to the "on" position in order to allow automatic completion of the cycle.
Flow control valve 240 is an adjustable valve which controls air flow within pneumatic system 200 and permits adjustment of the speed with which the various rods are extended and retracted. Such adjustment also controls various time intervals of operation as will be more fully understood by reference to the timing diagram shown in FIG. 9.
The time period T 1 shown in FIG. 9 is the time delay between the retraction of rod 64 which causes hanger 23 to be "fed" from feeder 14 into work portion 12 and the time at which rods 120 and 122 are extended to open tongues 33 and 35. Time T 1 is a function of how long it takes hanger 23 to come to rest at the work station and this delay may be incorporated into pneumatic system 200 by purely conventional means. Time period T 2 is the time during which the tongues are held open for use by a user. Time period T 3 is the time delay between the retraction of rods 120 and 122 and the beginning of the next cycle by feeding the next hanger. Time T 3 permits a user to remove a hanger with a garment hung thereon from apparatus 10. These time delays T 2 and T 3 are a function of how fast a particular user may be able to use apparatus 10 and may also be set by purely conventional means. In the preferred embodiment disclosed herein time T 3 is set by the user who must depress lever 201 to initiate each cycle. However, those skilled in the art will understand that the operation of apparatus 10 could be automatically cyclic with various predetermined time periods T 1 , T 2 and T 3 automatically incorporated into apparatus 10.
Those skilled in the art will realize that numerous other modifications and improvements may be made on the preferred embodiment of the invention disclosed herein without departing from the spirit and scope thereof. | This invention selectively opens and closes the paired clamping members of a flexible skirt hanger by imparting predetermined forces to predetermined parts of said hanger in a predetermined manner. The hanger is held at a work station in a frame during a predetermined work operation which causes said forces to be applied. A pneumatically extended rod causes one of said paired clamping members to move in a predetermined rotational direction while a portion of said frame limits rotations of the other of said clamping members in said predetermined rotational direction, thereby effectively imparting a force to said other clamping member causing it to move in a direction opposite said predetermined rotational direction. The opposite rotational motion of each of said clamping members causes them to open to receive a garment therebetween. Means are provided to close said clamping members on said garment by removing said forces and enabling said clamping members to tend to resume their equilibrium position. The invention also comprises means for automatically feeding one hanger at a time into said work station. | 1 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a substrate processing apparatus that subjects substrates to various types of processing.
[0003] 2. Description of the Background Art
[0004] Substrate processing apparatuses are used to subject various types of substrates such as semiconductor substrates, substrates for liquid crystal displays, plasma displays, optical disks, magnetic disks, magneto-optical disks, and photomasks, and other substrates to various types of processing.
[0005] For example, a substrate processing apparatus described in JP 2003-324139 A includes a plurality of processing blocks. Each processing block is provided with a plurality of thermal processing sections, a plurality of chemical solution processing sections and a transport mechanism. In each processing block, substrates are transported to the thermal processing sections and the chemical solution processing sections by the transport mechanism. Then, the substrates are subjected to predetermined processing in the thermal processing sections and the chemical solution processing sections.
[0006] More improved throughput of each processing block is required for improving throughput of the substrate processing apparatus. Examples of the method of improving the throughput of each processing block include reducing a time period required for transporting the substrates by the transport mechanism.
[0007] However, it is difficult to further speed up transportation of the substrates, because the transport speed of the substrates by the transport mechanism has been set sufficiently high.
SUMMARY OF THE INVENTION
[0008] An object of the present invention is to provide a substrate processing apparatus in which throughput can be improved.
[0009] (1) According to an aspect of the present invention, a substrate processing apparatus that is arranged adjacent to an exposure device includes a processing section that subjects a substrate to processing, an interface that is arranged between the processing section and the exposure device, subjects the substrate to processing, and carries the substrate in and out of the exposure device, and a first placement section that is arranged between the processing section and the interface and in which the substrate is to be placed, wherein the interface includes first and second processing regions for subjecting the substrate to the processing, a first substrate transport mechanism that is configured to transport the substrate among the first placement section, the first processing region and the exposure device, and a second substrate transport mechanism that is configured to transport the substrate among the first placement section, the second processing region and the exposure device.
[0010] In the substrate processing apparatus, the substrate is subjected to the predetermined processing in the processing section, and subsequently transported to the interface through the first placement section. Then, the substrate is carried from the interface into the exposure device. The substrate subjected to exposure processing in the exposure device is transported to the interface. At least one of a substrate before the exposure processing and a substrate after the exposure processing is subjected to the predetermined processing in the first and second processing regions in the interface.
[0011] In this case, the substrate can be transported by the first substrate transport mechanism among the first placement section, the first processing region and the exposure device. In addition, the substrate can be transported by the second substrate transport mechanism among the first placement section, the second processing region and the exposure device. This allows a wider choice of transport paths of the substrate to be available in the interface.
[0012] Accordingly, the substrate can be transported through an optimum path depending on how the substrate is to be processed in the processing section and the first and second processing regions. This allows transport efficiency of the substrate to be increased, resulting in improved throughput.
[0013] (2) The first and second processing regions may each include at least one of a cleaning processing unit that subjects a substrate before exposure processing to cleaning processing and a drying processing unit that subjects a substrate after the exposure processing to drying processing.
[0014] In this case, the substrate before the exposure processing is subjected to the cleaning processing by the cleaning processing unit to prevent contamination in the exposure device.
[0015] Moreover, the drying processing unit subjects the substrate after the exposure processing to the drying processing. Therefore, even though a liquid adheres to the substrate in the exposure device, the liquid can be prevented from dropping in the substrate processing apparatus. Also, components on the substrate can be prevented from being eluted in the liquid adhering to the substrate, and dust or the like in an atmosphere can be prevented from adhering to the liquid that adheres to the substrate.
[0016] (3) The first substrate transport mechanism may transport a substrate before exposure processing, and the second substrate transport mechanism may transport a substrate after the exposure processing.
[0017] In this case, an independent transport path is ensured for each of the substrate before the exposure processing and the substrate after the exposure processing in the interface. Thus, the substrate can be more efficiently transported than the case of complicated transport paths for the substrate before the exposure processing and the substrate after the exposure processing, resulting in the improved throughput.
[0018] Moreover, the substrate before the exposure processing and the substrate after the exposure processing do not come into indirect contact with each other in the interface. This prevents cross-contamination between the substrate before the exposure processing and the substrate after the exposure processing.
[0019] (4) The first placement section may be configured such that a plurality of substrates can be placed in the first placement section.
[0020] In this case, the substrates are temporarily housed in the first placement section to easily adjust the transport speed of the substrate.
[0021] (5) The interface may include a processing block for subjecting the substrate to the processing, a carry-in/carry-out block for carrying the substrate in and out of the exposure device, and a second placement section that is arranged between the processing block and the carry-in/carry-out block and in which the substrate is to be placed, the first and second processing regions may be provided in the processing block, the first substrate transport mechanism may include a first substrate holder that is provided in the processing block and configured to hold and transport the substrate among the first placement section, the first processing region and the second placement section, and a second substrate holder that is provided in the carry-in/carry-out block and configured to hold and transport the substrate between the second placement section and the exposure device, and the second substrate transport mechanism may include a third substrate holder that is configured to hold and transport the substrate among the first placement section, the second processing region and the second placement section in the processing block, and a fourth substrate holder that is provided in the carry-in/carry-out block and configured to hold and transport the substrate between the second placement section and the exposure device.
[0022] In this case, the substrate can be held and transported among the first placement section, the first processing region and the second placement section by the first substrate holder, and the substrate can be held and transported among the first placement section, the second processing region and the second placement section by the third substrate holder in the processing block. In addition, the substrate can be held and transported between the second placement section and the exposure device by the second and fourth substrate holders in the carry-in/carry-out block.
[0023] This allows a wider choice of transport paths of the substrate to be available in the processing block. In addition, the substrate can be carried in and out of the exposure device with simple operation in the carry-in/carry-out block. Therefore, the transport path of the substrate in the processing block is optimized to easily improve the transport efficiency of the substrate.
[0024] (6) The first substrate transport mechanism may include a first transport device that is provided in the processing block and includes the first substrate holder, and a second transport device that is provided in the processing block and includes the third substrate holder, the processing section, the processing block, the carry-in/carry-out block and the exposure device may be provided side by side along a first direction, the first and second processing regions and the first and second transport devices may be arranged along a second direction perpendicular to the first direction within a horizontal plane in the processing block, and the first and second transport devices may be arranged between the first and second processing regions, and the first transport device may be arranged on a side of the first processing region and the second transport device may be arranged on a side of the second processing region.
[0025] In this case, an increase in the size of the substrate processing apparatus can be suppressed while the transport efficiency of the substrate in the interface can be reliably improved.
[0026] (7) The processing section may include a plurality of processing chambers that are hierarchically provided, a plurality of liquid processing units that are provided in the plurality of processing chambers, respectively, and each subject the substrate to liquid processing, a plurality of transport chambers that are hierarchically provided, and a plurality of transport mechanisms for the transport chambers that are provided in the plurality of transport chambers, respectively, and each transport the substrate.
[0027] In this case, the substrates are subjected to the liquid processing by the plurality of liquid processing units in the plurality of processing chambers. Moreover, the substrates after the liquid processing are transported by the plurality of transport mechanisms for the transport chambers in the plurality of transport chambers. Accordingly, the substrates can be concurrently processed and transported by the plurality of liquid processing units and the plurality of transport mechanisms for the transport chambers, thus improving the throughput of the substrate processing apparatus.
[0028] Moreover, the plurality of processing chambers are hierarchically provided and the plurality of transport chambers are hierarchically provided, thereby making it possible to provide the plurality of liquid processing chambers and the plurality of transport chambers without increasing footprint of the substrate processing apparatus.
[0029] (8) The plurality of processing chambers may include a first processing chamber group and a second processing chamber group, the plurality of transport chambers may include a first transport chamber and a second transport chamber, and the first transport chamber may be provided adjacent to the first processing chamber group, and the second transport chamber may be provided adjacent to the second processing chamber group.
[0030] In this case, the substrate processed in the first processing chamber group can be transported by the transport mechanism for the transport chamber in the first transport chamber, and the substrate processed in the second processing chamber group can be transported by the transport mechanism for the transport chamber in the second transport chamber. This allows the plurality of substrates to be smoothly distributed to the first and second processing chamber groups, thus sufficiently improving the throughput of the substrate processing apparatus.
[0031] Even when one transport mechanism for the transport chamber of the transport mechanisms for the transport chambers in the first and second transport chambers is stopped because of malfunction, a maintenance operation and so on, the substrates can be continuously transported and processed using the other transport mechanism for the transport chamber and the liquid processing unit of the processing chamber group corresponding to the transport mechanism for the transport chamber.
[0032] Furthermore, even when the use of one processing chamber group of the first and second processing chamber groups is stopped because of malfunction, a maintenance operation and so on, the substrates can be continuously processed and transported using the liquid processing unit of the other processing chamber group and the transport mechanism for the transport chamber corresponding to the processing chamber group.
[0033] (9) The first placement section may include a first placement portion that is provided between the first transport chamber and the interface, and a second placement portion that is provided between the second transport chamber and the interface, the plurality of transport mechanisms for the transport chambers may include a first in-chamber transport mechanism that is provided in the first transport chamber, a second in-chamber transport mechanism that is provided in the second transport chamber, the first in-chamber transport mechanism may be configured to transport the substrate to the first placement portion, and the second in-chamber transport mechanism may be configured to transport the substrate to the second placement portion.
[0034] In this case, the substrate processed in the first processing chamber group can be transported to the first placement portion by the first in-chamber transport mechanism, and the substrate processed in the second processing chamber group can be transported to the second placement portion by the second in-chamber transport mechanism. In addition, the substrates can be transported by the first and second substrate transport mechanisms between the first and second placement portions and the exposure device. As a result, the substrates can be smoothly transported among the first and second processing chamber groups, the interface and the exposure device.
[0035] According to the present invention, the transport efficiency of the substrates can be improved and the throughput can be improved.
[0036] Other features, elements, characteristics, and advantages of the present invention will become more apparent from the following description of preferred embodiments of the present invention with reference to the attached drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0037] FIG. 1 is a plan view of a substrate processing apparatus according to an embodiment of the present invention.
[0038] FIG. 2 is a diagram of a coating processing section, a coating/development processing section and a cleaning/drying processing section of FIG. 1 that are seen from a +Y direction.
[0039] FIG. 3 is a diagram of thermal processing sections and the cleaning/drying processing section of FIG. 1 that are seen from a −Y direction.
[0040] FIG. 4 is a diagram of the coating processing section, a transport section and the thermal processing section of FIG. 1 that are seen from a −X direction.
[0041] FIG. 5 is a diagram of the transport sections that are seen from the −Y direction.
[0042] FIG. 6 is a perspective view showing a transport mechanism.
[0043] FIG. 7 is a diagram showing the internal configuration of a cleaning/drying processing block.
[0044] FIG. 8 is a perspective view showing the appearance of a placement/buffer section.
[0045] FIG. 9 is a side view of the placement/buffer section.
[0046] FIG. 10 is a plan view for explaining an operation of carrying a substrate W in and out of the placement/buffer section.
[0047] FIG. 11 is a perspective view showing the appearance of placement/cooling sections.
[0048] FIG. 12 is a diagram of the placement/cooling sections that is seen from a +X direction.
[0049] FIG. 13 is a schematic transverse sectional view of the placement/cooling section.
[0050] FIG. 14 is a schematic sectional view for explaining an operation of carrying the substrate W in and out of the placement/cooling section.
[0051] FIG. 15 is a diagram showing the internal configuration of the cleaning/drying processing block in a first modification.
[0052] FIG. 16 is a diagram showing the internal configuration of the cleaning/drying processing block in a second modification.
[0053] FIG. 17 is a diagram showing the internal configuration of the cleaning/drying processing block in a third modification.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0054] A substrate processing apparatus according to embodiments of the present invention will be described with reference to the drawings. In the following description, a substrate refers to a semiconductor substrate, a substrate for a liquid crystal display, a substrate for a plasma display, a glass substrate for a photomask, a substrate for an optical disk, a substrate for a magnetic disk, a substrate for a magneto-optical disk, a substrate for a photomask or the like.
[0055] (1) Configuration of Substrate Processing Apparatus
[0056] FIG. 1 is a plan view of a substrate processing apparatus according to an embodiment of the present invention.
[0057] FIG. 1 and the following predetermined drawings are accompanied by arrows that respectively indicate X, Y, and Z directions perpendicular to one another for clarity of a positional relationship. The X and Y directions are perpendicular to each other within a horizontal plane, and the Z direction corresponds to a vertical direction. In each of the directions, the direction of the arrow is defined as a +direction, and the opposite direction is defined as a −direction.
[0058] As shown in FIG. 1 , the substrate processing apparatus 100 includes an indexer block 11 , a first processing block 12 , a second processing block 13 , a cleaning/drying processing block 14 A and a carry-in/carry-out block 14 B. The cleaning/drying processing block 14 A and the carry-in/carry-out block 14 B constitute an interface block 14 . An exposure device 15 is arranged adjacent to the carry-in/carry-out block 14 B. The exposure device 15 subjects a substrate W to exposure processing by means of a liquid immersion method.
[0059] As shown in FIG. 1 , the indexer block 11 includes a plurality of carrier platforms 111 and a transport section 112 . A carrier 113 that houses a plurality of substrates W in multiple stages is placed on each carrier platform 111 . Although FOUPs (Front Opening Unified Pods) are adopted as the carriers 113 in the present embodiment, the present invention is not limited to the same. For example, SMIF (Standard Mechanical Inter Face) pods, or OCs (Open Cassettes) that expose the hosued substrates W to outside air may be used.
[0060] A controller 114 and a transport mechanism 115 are provided in the transport section 112 . The controller 114 controls various components in the substrate processing apparatus 100 . The transport mechanism 115 has a hand 116 for holding the substrate W. The transport mechanism 115 holds and transports the substrate W using the hand 116 . In addition, an opening 117 through which the substrates W are received and transferred between the carriers 113 and the transport mechanism 115 is formed in the transport section 112 as described below referring to FIG. 5 .
[0061] The first processing block 12 includes a coating processing section 121 , a transport section 122 and a thermal processing section 123 . The coating processing section 121 and the thermal processing section 123 are provided to be opposite to each other with the transport section 122 sandwiched therebetween. A substrate platform PASS 1 and substrate platforms PASS 2 to PASS 4 (see FIG. 5 ), described later, on which the substrates W are to be placed, are provided between the transport section 122 and the indexer block 11 . A transport mechanism 127 that transports the substrates W and a transport mechanism 128 (see FIG. 5 ), described below, are provided in the transport section 122 .
[0062] The second processing block 13 includes a coating/development processing section 131 , a transport section 132 and a thermal processing section 133 . The coating/development processing section 131 and the thermal processing section 133 are provided to be opposite to each other with the transport section 132 sandwiched therebetween. A substrate platform PASS 5 and substrate platforms PASS 6 to PASS 8 (see FIG. 5 ), described below, on which the substrates W are to be placed are provided between the transport section 132 and the transport section 122 . A transport mechanism 137 and a transport mechanism 138 (see FIG. 5 ), described below, that transport the substrates W are provided in the transport section 132 . A gasket 145 is provided between the thermal processing section 133 and the interface block 14 in the second processing block 13 .
[0063] The cleaning/drying processing block 14 A includes cleaning/drying processing sections 161 , 162 and a transport section 163 . The cleaning/drying processing sections 161 , 162 are provided to be opposite to each other with the transport section 163 sandwiched therebetween. Transport mechanisms 141 , 142 are provided in the transport section 163 .
[0064] A placement/buffer section P-BF 1 and a placement/buffer section P-BF 2 (see FIG. 5 ), described below, are provided between the transport section 163 and the transport section 132 . The placement/buffer sections P-BF 1 , P-BF 2 are configured to house the plurality of substrates W therein.
[0065] Moreover, a substrate platform PASS 9 and placement/cooling sections P-CP (see FIG. 5 ) that are described below are provided between the transport mechanisms 141 , 142 so as to be adjacent to the carry-in/carry-out block 14 B. The placement/cooling sections P-CP each have a function of cooling the substrates W (a cooling plate, for example). The substrates W are cooled to a temperature suitable for the exposure processing in the placement/cooling sections P-CP.
[0066] A transport mechanism 146 is provided in the carry-in/carry-out block 14 B. The transport mechanism 146 carries the substrates W in and out of the exposure device 15 . A substrate carry-in section 15 a for carrying the substrate W in and a substrate carry-out section 15 b for carrying the substrate W out are provided in the exposure device 15 . Note that the substrate carry-in section 15 a and the substrate carry-out section 15 b of the exposure device 15 may be arranged to be adjacent to each other in a horizontal direction or may be arranged one above the other.
[0067] Here, the carry-in/carry-out block 14 B is provided to be movable in a +Y direction and a −Y direction with respect to the cleaning/drying processing block 14 A. The carry-in/carry-out block 14 B can be moved in a +Y direction or a −Y direction to ensure a working space for maintenance operation of the cleaning/drying processing block 14 A, the carry-in/carry-out block 14 B and the exposure device 15 . Note that the carry-in/carry-out block 14 B can be easily moved because of its lighter weight than the other blocks.
[0068] Note that a significant amount of liquid (a cleaning liquid and a rinse liquid, for example) is used in the cleaning/drying processing sections 161 , 162 in the cleaning/drying processing bock 14 A. Therefore, the cleaning/drying processing block 14 A needs to be reliably connected to equipment for supplying the liquid. Meanwhile, liquid is hardly used in the carry-in/carry-out block 14 B. Therefore, the carry-in/carry-out block 14 B can be connected to the equipment in a simplified manner. That is, the carry-in/carry-out block 14 B can be easily separated from and reconnected to the equipment.
[0069] Accordingly, only the carry-in/carry-out block 14 B is moved while the cleaning/drying processing block 14 A is not moved at the time of the maintenance operation of the cleaning/drying processing block 14 A, the carry-in/carry-out block 14 B and the exposure device 15 , thus significantly reducing the labor of workers and working time.
[0070] (2) Configurations of the Coating Processing Section and the Development Processing Section
[0071] FIG. 2 is a diagram of the coating processing section 121 , the coating/development processing section 131 and the cleaning/drying processing section 161 of FIG. 1 that are seen from the +Y direction.
[0072] As shown in FIG. 2 , coating processing chambers 21 , 22 , 23 , 24 are hierarchically provided in the coating processing section 121 . A coating processing unit 129 is provided in each of the coating processing chambers 21 to 24 . Development processing chambers 31 , 33 and coating processing chambers 32 , 34 are hierarchically provided in the coating/development processing section 131 . A development processing unit 139 is provided in each of the development processing chambers 31 , 33 and a coating processing unit 129 is provided in each of the coating processing chambers 32 , 34 .
[0073] Each coating processing unit 129 includes spin chucks 25 that hold the substrates W and cups 27 provided to cover the periphery of the spin chucks 25 . In the present embodiment, each coating processing unit 129 is provided with two spin chucks 25 and two cups 27 . The spin chucks 25 are rotated by a driving device (an electric motor, for example) that is not shown.
[0074] In addition, each coating processing unit 129 includes a plurality of nozzles 28 that discharge processing liquid and a nozzle transport mechanism 29 that transports the nozzles 28 as shown in FIG. 1 .
[0075] In the coating processing unit 129 , any one of the plurality of nozzles 28 is moved above the substrate W by the nozzle transport mechanism 29 . The processing liquid is then discharged from the nozzle 28 to be applied onto the substrate W. Note that the spin chuck 25 is rotated by the driving device, not shown, when the processing liquid is supplied from the nozzle 28 onto the substrate W, thus causing the substrate W to be rotated.
[0076] In the present embodiment, a processing liquid for an antireflection film is supplied from the nozzles 28 onto the substrates W in the coating processing units 129 of the coating processing chambers 22 , 24 . A processing liquid for a resist film is supplied from the nozzles 28 onto the substrates W in the coating processing units 129 of the coating processing chambers 21 , 23 . A processing liquid for a resist cover film is supplied from the nozzles 28 onto the substrates W in the coating processing units 129 of the coating processing chambers 32 , 34 .
[0077] Similarly to the coating processing unit 129 , each development processing unit 139 includes the spin chucks 35 and the cups 37 as shown in FIG. 2 . Each development processing unit 139 includes two slit nozzles 38 that discharge development liquids and a moving mechanism 39 that moves the slit nozzles 38 in the X direction as shown in FIG. 1 .
[0078] In the development processing unit 139 , first, one slit nozzle 38 supplies the development liquid onto each substrate W while moving in the X direction. Then, the other slit nozzle 38 supplies the development liquid onto each substrate W while moving. Note that the spin chucks 35 are rotated by the driving device, not shown, when the development liquid is supplied from the slit nozzles 38 onto the substrates W to cause the substrates W to be rotated.
[0079] In the present embodiment, the development liquid is supplied onto the substrates W, so that the resist cover films on the substrates W are removed and the development processing is performed to the substrates W in the development processing unit 139 . In addition, the different development liquids are discharged from the two slit nozzles 38 in the present embodiment. Accordingly, the two kinds of development liquids can be supplied onto each substrate W.
[0080] While the coating processing unit 129 includes the two cups 27 and the development processing unit 139 includes the three cups 37 in the example of FIG. 2 , the coating processing unit 129 may include three cups 27 and the development processing unit 139 may include two cups 37 .
[0081] A plurality of (four in this example) cleaning/drying processing units SD1 are provided in the cleaning/drying processing section 161 . The substrates W before the exposure processing are subjected to the cleaning processing and the drying processing in the cleaning/drying processing units SD1.
[0082] Note that polishing processing may be performed to a back surface of the substrate W and an end (a bevel portion) of the substrate W using a brush or the like in each cleaning/drying processing unit SD1. Here, the back surface of the substrate W means an opposite side of the surface of the substrate W on which various patterns such as a circuit pattern are to be formed.
[0083] As shown in FIG. 2 , air supply units 41 for supplying clean air whose temperature and humidity are adjusted into the coating processing chambers 21 to 24 , 32 , 34 are provided above the coating processing units 129 in the coating processing chambers 21 to 24 , 32 , 34 . In addition, air supply units 47 for supplying clean air whose temperature and humidity are adjusted into the development processing chambers 31 , 33 are provided above the development processing units 139 in the development processing chambers 31 , 33 .
[0084] An exhaust unit 42 for exhausting an atmosphere within the cup 27 is provided below the coating processing unit 129 in each of the coating processing chambers 21 to 24 , 32 , 34 . An exhaust unit 48 for exhausting an atmosphere within the cup 37 is provided below the development processing unit 139 in each of the development processing chambers 31 , 33 .
[0085] As shown in FIGS. 1 and 2 , a fluid box 50 is provided in the coating processing section 121 so as to be adjacent to the coating/development processing section 131 . Similarly, a fluid box 60 is provided in the coating/development processing section 131 so as to be adjacent to the cleaning/drying processing block 14 A. The fluid box 50 and the fluid box 60 each house fluid related elements such as a pipe, a joint, a valve, a flowmeter, a regulator, a pump, a temperature adjuster used to supply a chemical solution to the coating processing units 129 and the development processing units 139 and discharge the chemical solution and air out of the coating processing units 129 and the development processing units 139 .
[0086] (3) Configurations of the Thermal Processing Sections
[0087] FIG. 3 is a diagram of the thermal processing sections 122 , 133 and the cleaning/drying processing section 162 of FIG. 1 that are seen from the −Y direction.
[0088] As shown in FIG. 3 , the thermal processing section 123 has an upper stage thermal processing portion 301 provided above and a lower stage thermal processing portion 302 provided below. The upper stage thermal processing portion 301 and the lower stage thermal processing portion 302 are each provided with a plurality of thermal processing units PHP, a plurality of adhesion reinforcing processing units PAHP and a plurality of cooling units CP.
[0089] The substrates W are subjected to thermal processing and cooling processing in the thermal processing units PHP. Adhesion reinforcing processing for improving adhesion between the substrates W and the antireflection films is performed in the adhesion reinforcing processing units PAHP. Specifically, an adhesion reinforcing agent such as HMDS (hexametyldisilazane) is applied to the substrates W and the thermal processing is performed to the substrates W in the adhesion reinforcing processing units PAHP. In the cooling unit CP, the substrates W are subjected to cooling processing.
[0090] The thermal processing section 133 includes an upper stage thermal processing portion 303 provided above and a lower stage thermal processing portion 304 provided below. The upper stage thermal processing portion 303 and the lower stage thermal processing portion 304 are each provided with a cooling unit CP, a plurality of thermal processing units PHP and an edge exposure portion EEW. The exposure processing is performed to peripheral portions of the substrates W in the edge exposure portion EEW.
[0091] In addition, a plurality of (five in this example) cleaning/drying processing units SD2 are provided in the cleaning/drying processing section 162 . The substrates W after the exposure processing are subjected to the cleaning processing and the drying processing in the cleaning/drying processing units SD2.
[0092] (4) Configuration of the Transport Sections
[0093] (4-1) Schematic Configuration
[0094] FIG. 4 is a diagram of the coating processing section 121 , the transport section 122 and the thermal processing section 123 of FIG. 1 that are seen from the −X direction. FIG. 5 is a diagram of the transport sections 122 , 132 , 163 that are seen from the −Y direction.
[0095] As shown in FIGS. 4 and 5 , the transport section 122 has an upper stage transport chamber 125 and a lower stage transport chamber 126 . The transport section 132 has an upper stage transport chamber 135 and a lower stage transport chamber 136 .
[0096] The transport mechanism 127 is provided in the upper stage transport chamber 125 and the transport mechanism 128 is provided in the lower stage transport chamber 126 . The transport mechanism 137 is provided in the upper stage transport chamber 135 and the transport mechanism 138 is provided in the lower stage transport chamber 136 .
[0097] As shown in FIG. 4 , the coating processing chambers 21 , 22 are provided to be opposite to the upper stage thermal processing portion 301 with the upper stage transport chamber 125 sandwiched therebetween, and the coating processing chambers 23 , 24 are provided to be opposite to the lower stage thermal processing portion 302 with the lower stage transport chamber 126 sandwiched therebetween. Similarly, the development processing chamber 31 and the coating processing chamber 32 ( FIG. 2 ) are provided to be opposite to the upper stage thermal processing portion 303 ( FIG. 3 ) with the upper stage transport chamber 135 ( FIG. 5 ) sandwiched therebetween, and the development processing chamber 33 and the coating processing chamber 34 ( FIG. 2 ) are provided to be opposite to the lower stage thermal processing portion 304 ( FIG. 3 ) with the lower stage transport chamber 136 ( FIG. 5 ) sandwiched therebetween.
[0098] As shown in FIG. 5 , the substrate platforms PASS 1 , PASS 2 are provided between the transport section 112 and the upper stage transport chamber 125 , and the substrate platforms PASS 3 , PASS 4 are provided between the transport section 112 and the lower stage transport chamber 126 . The substrate platforms PASS 5 , PASS 6 are provided between the upper stage transport chamber 125 and the upper stage transport chamber 135 , and the substrate platforms PASS 7 , PASS 8 are provided between the lower stage transport chamber 126 and the lower stage transport chamber 136 .
[0099] The placement/buffer section P-BF 1 is provided between the upper stage transport chamber 135 and the transport section 163 , and the placement/buffer section P-BF 2 is provided between the lower stage transport chamber 136 and the transport section 163 . The substrate platform PASS 9 and the plurality of placement/cooling sections P-CP are provided in the transport section 163 so as to be adjacent to the carry-in/carry-out block 14 B.
[0100] The placement/buffer section P-BF 1 is configured such that the substrates W can be carried in and out by the transport mechanism 137 and the transport mechanisms 141 , 142 ( FIG. 1 ). The placement/buffer section P-BF 2 is configured such that the substrates W can be carried in and out by the transport mechanism 138 and the transport mechanisms 141 , 142 ( FIG. 1 ). The substrate platform PASS 9 and the placement/cooling sections P-FP are configured such that the substrates W can be carried in and out by the transport mechanisms 141 , 142 ( FIG. 1 ) and the transport mechanism 146 .
[0101] While the one substrate platform PASS 9 is provided in the example of FIG. 5 , a plurality of substrate platforms PASS 9 may be provided one above another. In this case, the plurality of substrate platforms PASS 9 may be used as buffer portions on which the substrates W are temporarily placed.
[0102] In the present embodiment, the substrates W to be transported from the indexer block 11 to the first processing block 12 are placed on the substrate platform PASS 1 and the substrate platform PASS 3 , and the substrates W to be transported from the first processing block 12 to the indexer block 11 are placed on the substrate platform PASS 2 and the substrate platform PASS 4 .
[0103] The substrates W to be transported from the first processing block 12 to the second processing block 13 are placed on the substrate platform PASS 5 and the substrate platform PASS 7 , and the substrates W to be transported from the second processing block 13 to the first processing block 12 are placed on the substrate platform PASS 6 and the substrate platform PASS 8 .
[0104] The substrates W to be transported from the second processing block 13 to the cleaning/drying processing block 14 A are placed in the placement/buffer sections P-BF 1 , P-BF 2 , the substrates W to be transported from the cleaning/drying processing block 14 A to the carry-in/carry-out block 14 B are placed in the placement/cooling sections P-CP, and the substrates W to be transported from the carry-in/carry-out block 14 B to the cleaning/drying processing block 14 A is placed on the substrate platform PASS 9 .
[0105] An air supply unit 43 is provided above the transport mechanism 127 within the upper stage transport chamber 125 , and an air supply unit 43 is provided above the transport mechanism 128 in the lower stage transport chamber 126 . An air supply unit 43 is provided above the transport mechanism 137 within the upper stage transport chamber 135 , and the air supply unit 43 is provided above the transport mechanism 138 within the lower stage transport chamber 136 . Air whose temperature and humidity is adjusted is supplied from a temperature adjustment device, not shown, to the air supply units 43 .
[0106] In addition, an exhaust unit 44 for exhausting air in the upper stage transport chamber 125 is provided below the transport mechanism 127 within the upper stage transport chamber 125 , and an exhaust unit 44 for exhausting air in the lower stage transport chamber 126 is provided below the transport mechanism 128 within the lower stage transport chamber 126 .
[0107] Similarly, an exhaust unit 44 for exhausting air in the upper stage transport chamber 135 is provided below the transport mechanism 137 within the upper stage transport chamber 135 , and an exhaust unit 44 for exhausting air in the lower stage transport chamber 136 is provided below the transport mechanism 138 within the lower stage transport chamber 136 .
[0108] Accordingly, the atmosphere in the upper stage transport chambers 125 , 135 and the lower stage transport chambers 126 , 136 is maintained in a clean state with suitable temperature and humidity.
[0109] An air supply unit 45 is provided in an upper portion within the transport section 163 of the cleaning/drying processing block 14 A. An air supply unit 46 is provided in an upper portion within the carry-in/carry-out block 14 B. Air whose temperature and humidity are adjusted is supplied from the temperature adjustment device, not shown, to the air supply units 45 , 46 . Accordingly, the atmosphere in the cleaning/drying processing block 14 A and the carry-in/carry-out block 14 B is maintained in a clean state with suitable temperature and humidity.
[0110] (4-2) Configuration of the Transport Mechanism
[0111] Next, description will be made of the transport mechanism 127 . FIG. 6 is a perspective view showing the transport mechanism 127 .
[0112] As shown in FIGS. 5 and 6 , the transport mechanism 127 has long-sized guide rails 311 , 312 . As shown in FIG. 5 , the guide rail 311 is fixed to the side of the transport section 112 to extend in the vertical direction in the upper stage transport chamber 125 . The guide rail 312 is fixed to the side of the upper stage transport chamber 135 to extend in the vertical direction in the upper stage transport chamber 125 .
[0113] As shown in FIGS. 5 and 6 , a long-sized guide rail 313 is provided between the guide rail 311 and the guide rail 312 . The guide rail 313 is attached to the guide rails 311 , 312 in a vertically movable manner. A moving member 314 is attached to the guide rail 313 . The moving member 314 is provided in a movable manner in a longitudinal direction of the guide rail 313 .
[0114] A long-sized rotating member 315 is provided on an upper surface of the moving member 314 in a rotatable manner. A hand H 1 and a hand H 2 for holding the substrates W are attached to the rotating member 315 . The hands H 1 , H 2 are provided in a movable manner in a longitudinal direction of the rotating member 315 .
[0115] The above-described configuration allows the transport mechanism 127 to freely move in the X direction and the Z direction within the upper stage transport chamber 125 . In addition, the substrates W can be transferred among the coating processing chambers 21 , 22 ( FIG. 2 ), the substrate platforms PASS 1 , PASS 2 , PASS 5 , PASS 6 ( FIG. 5 ) and the upper stage thermal processing portion 301 ( FIG. 3 ) using the hands H 1 , H 2 .
[0116] Note that the transport mechanisms 128 , 137 , 138 each have the same configuration as the transport mechanism 127 as shown in FIG. 5 .
[0117] (5) Configuration of the Cleaning/Drying Processing Block
[0118] FIG. 7 is a diagram showing the internal configuration of the cleaning/drying processing block 14 A. Note that FIG. 7 is a diagram of the cleaning/drying processing block 14 A that is seen from the +X direction.
[0119] As shown in FIG. 7 , the transport mechanism 141 has hands H 3 , H 4 for holding the substrates W, and the transport mechanism 142 has hands H 5 , H 6 for holding the substrates W.
[0120] The cleaning/drying processing units SD1 are hierarchically provided on the +Y side of the transport mechanism 141 , and the cleaning/drying processing units SD2 are hierarchically provided on the −Y side of the transport mechanism 142 . The placement/buffer sections P-BF 1 , P-BF 2 are provided one above the other on the −X side between the transport mechanisms 141 , 142 .
[0121] The thermal processing units PHP of the upper stage thermal processing portion 303 and the lower stage thermal processing portion 304 are configured such that the substrates W can be carried in from the cleaning/drying processing block 14 A.
[0122] (6) Operation of Each Component of the Substrate Processing Apparatus
[0123] Description will be made of the operation of each component of the substrate processing apparatus 100 according to the present embodiment.
[0124] (6-1) Operation of the Indexer Block 11
[0125] Description will be made of the operation of the indexer block 11 mainly referring to FIGS. 1 and 5 .
[0126] First, the carriers 113 in which unprocessed substrates W are housed are placed on the carrier platforms 111 of the indexer block 11 in the substrate processing apparatus 100 according to the present embodiment. The transport mechanism 115 takes out one substrate W from the carrier 113 , and transports the substrate W to the substrate platform PASS 1 . Then, the transport mechanism 115 takes out another unprocessed substrate W from the carrier 113 , and transports the substrate W to the substrate platform PASS 3 ( FIG. 5 ).
[0127] Note that when a processed substrate W is placed on the substrate platform PASS 2 ( FIG. 5 ), the transport mechanism 115 transports the unprocessed substrate W to the substrate platform PASS 1 and subsequently takes out the processed substrate W from the substrate platform PASS 2 . Then, the transport mechanism 115 transports the processed substrate W to the carrier 113 . Similarly, when a processed substrate W is placed on the substrate platform PASS 4 , the transport mechanism 115 transports the unprocessed substrate W to the substrate platform PASS 3 , and subsequently takes out the processed substrate W from the substrate platform PASS 4 . Then, the processed substrate W is transported to the carrier 113 by the transport mechanism 115 to be housed in the carrier 113 .
[0128] ( 6 - 2 ) Operation of the First Processing Block 12
[0129] Description will be made of the operation of the first processing block 12 mainly referring to FIGS. 1 to 3 and 5 . Note that movement of the transport mechanisms 127 , 128 in the X direction and the Z direction is not explained in the following paragraphs for simplicity.
[0130] The substrate W placed on the substrate platform PASS 1 ( FIG. 5 ) by the transport mechanism 115 ( FIG. 5 ) is taken out by the hand H 1 of the transport mechanism 127 ( FIG. 5 ). The transport mechanism 127 places the substrate W held by the hand H 2 on the substrate platform PASS 2 . Note that the substrate W placed on the substrate platform PASS 2 by the hand H 2 is the substrate W after the development processing.
[0131] Next, the transport mechanism 127 takes out the substrate W after the adhesion reinforcing processing from a predetermined adhesion reinforcing processing unit PAHP ( FIG. 3 ) of the upper stage thermal processing portion 301 ( FIG. 3 ) using the hand H 2 . The transport mechanism 127 carries the unprocessed substrate W held by the hand H 1 in the adhesion reinforcing processing unit PAHP.
[0132] Next, the transport mechanism 127 takes out the substrate W after the cooling processing from a predetermined cooling unit CP of the upper stage thermal processing portion 301 ( FIG. 3 ) using the hand H 1 . The transport mechanism 127 carries the substrate W after the adhesion reinforcing processing held by the hand H 2 in the cooling unit CP. The substrate W is cooled to a temperature suitable for formation of the antireflection film in the cooling unit CP.
[0133] The transport mechanism 127 then takes out the substrate W after formation of the antireflection film from the spin chuck 25 ( FIG. 2 ) of the coating processing chamber 22 ( FIG. 2 ) using the hand H 2 . The transport mechanism 127 places the substrate W after the cooling processing held by the hand H 1 on the spin chuck 25 . The antireflection film is formed on the substrate W by the coating processing unit 129 ( FIG. 2 ) in the coating processing chamber 22 .
[0134] Next, the transport mechanism 127 takes out the substrate W after the thermal processing from a predetermined thermal processing unit PHP of the upper stage thermal processing portion 301 ( FIG. 3 ) using the hand H 1 . The transport mechanism 127 carries the substrate W after formation of the antireflection film held by the hand H 2 in the thermal processing unit PHP. The substrates W are successively subjected to the heating processing and the cooling processing in the thermal processing unit PHP.
[0135] The transport mechanism 127 subsequently takes out the substrate W after the cooling processing from a predetermined cooling unit CP ( FIG. 3 ) of the upper stage thermal processing portion 301 ( FIG. 4 ) using the hand H 2 . The transport mechanism 127 carries the substrate W after the thermal processing held by the hand H 1 in the cooling unit CP. The substrate W is cooled to a temperature suitable for resist film forming processing in the cooling unit CP.
[0136] The transport mechanism 127 then takes out the substrate W after formation of the resist film from the spin chuck 25 ( FIG. 2 ) of the coating processing chamber 21 ( FIG. 2 ) using the hand H 1 . The transport mechanism 127 places the substrate W after the cooling processing held by the hand H 2 on the spin chuck 25 . The resist film is formed on the substrate W by the coating processing unit 129 ( FIG. 2 ) in the coating processing chamber 22 .
[0137] Next, the transport mechanism 127 takes out the substrate W after the thermal processing from the predetermined thermal processing unit PHP of the upper stage thermal processing portion 301 ( FIG. 3 ) using the hand H 2 . The transport mechanism 127 carries the substrate W after formation of the resist film held by the hand H 1 in the thermal processing unit PHP.
[0138] The transport mechanism 127 then places the substrate W after the thermal processing held by the hand H 2 on the substrate platform PASS 5 ( FIG. 5 ). The transport mechanism 127 takes out the substrate W after the development processing from the substrate platform PASS 6 ( FIG. 5 ) using the hand H 2 . The transport mechanism 127 subsequently transports the substrate W after the development processing that has been taken out from the substrate platform PASS 6 to the substrate platform PASS 2 ( FIG. 5 ).
[0139] The transport mechanism 127 repeats the foregoing processing to cause the plurality of substrates W to be successively subjected to the predetermined processing in the first processing block 12 .
[0140] The transport mechanism 128 performs the same operation as the transport mechanism 127 to carry the substrates W in and out of the substrate platforms PASS 3 , PASS 4 , PASS 7 , PASS 8 ( FIG. 5 ), the coating processing chambers 23 , 24 ( FIG. 2 ) and the lower stage thermal processing portion 302 ( FIG. 4 ).
[0141] As described above, the substrates W transported by the transport mechanism 127 are processed in the coating processing chambers 21 , 22 and the upper stage thermal processing portion 301 , and the substrates W transported by the transport mechanism 128 are processed in the coating processing chambers 23 , 24 and the lower stage thermal processing portion 302 in the present embodiment. In this case, the plurality of substrates W can be simultaneously processed in the upper processing section (the coating processing chambers 21 , 22 and the upper stage thermal processing portion 301 ) and the lower processing section (the coating processing chambers 23 , 24 and the lower stage thermal processing portion 302 ). This improves throughput of the first processing block 12 without increasing the transport speed of the substrates W by the transport mechanisms 127 , 128 . The transport mechanisms 127 , 128 are provided one above the other, thus preventing an increase of footprint of the substrate processing apparatus 100 .
[0142] While the substrates W are subjected to the cooling processing in the cooling unit CP before the antireflection film forming processing in the coating processing chamber 22 in the foregoing example, the substrates W may not be subjected to the cooling processing in the cooling unit CP before the development processing if the antireflection film can be properly formed.
[0143] (6-3) Operation of the Second Processing Block 13
[0144] Description will be made of the operation of the second processing block 13 mainly referring to FIGS. 1 to 3 and 5 . Note that movement of the transport mechanisms 137 , 138 in the X direction and the Z direction is not explained in the following paragraphs for simplicity.
[0145] The substrate W placed on the substrate platform PASS 5 ( FIG. 5 ) by the transport mechanism 127 is taken out by the hand H 1 of the transport mechanism 137 ( FIG. 5 ). The transport mechanism 137 places the substrate W held by the hand H 2 on the substrate platform PASS 6 . Note that the substrate W placed on the substrate platform PASS 6 by the hand H 2 is the substrate W after the development processing.
[0146] Next, the transport mechanism 137 takes out the substrate W after formation of the resist cover film from the spin chuck 25 ( FIG. 2 ) of the coating processing chamber 32 ( FIG. 2 ) using the hand H 2 . The transport mechanism 137 places the substrate W after formation of the resist film held by the hand H 1 on the spin chuck 25 . The resist cover film is formed on the substrate W by the coating processing unit 129 ( FIG. 2 ) in the coating processing chamber 32 .
[0147] Next, the transport mechanism 137 takes out the substrate W after the thermal processing from a predetermined thermal processing unit PHP of the upper stage thermal processing portion 303 ( FIG. 3 ) using the hand H 1 . The transport mechanism 137 carries the substrate W after formation of the resist cover film held by the hand H 2 in the thermal processing unit PHP.
[0148] The transport mechanism 137 then takes out the substrate W after the edge exposure processing from the edge exposure section EEW ( FIG. 3 ) using the hand H 2 . The transport mechanism 137 carries the substrate W after the thermal processing held by the hand H 1 in the edge exposure section EEW. The peripheral portion of the substrate W is subjected to the exposure processing in the edge exposure section EEW.
[0149] Next, the transport mechanism 137 places the substrate W after the edge exposure processing held by the hand H 2 in the placement/buffer section P-BF 1 ( FIG. 5 ), and takes out the substrate W after the thermal processing from the thermal processing unit PHP of the upper stage thermal processing portion 301 ( FIG. 4 ) adjacent to the carry-in/carry-out block 14 A using the hand H 2 . Note that the substrate W taken out from the thermal processing unit PHP adjacent to the carry-in/carry-out block 14 A is the substrate W that has been subjected to the exposure processing in the exposure device 15 .
[0150] Next, the transport mechanism 137 takes out the substrate W after the cooling processing from a predetermined cooling unit CP ( FIG. 3 ) of the upper stage thermal processing portion 303 ( FIG. 3 ) using the hand H 1 . The transport mechanism 137 carries the substrate W after the exposure processing held by the hand H 2 in the cooling unit CP. The substrate W is cooled to a temperature suitable for the development processing in the cooling unit CP.
[0151] The transport mechanism 137 then takes out the substrate W after the development processing from the spin chuck 35 ( FIG. 2 ) of the development processing chamber 31 ( FIG. 2 ) using the hand H 2 . The transport mechanism 137 places the substrate W after the cooling processing held by the hand H 1 on the spin chuck 35 . Removing processing of the resist cover film and the development processing are performed by the development processing unit 139 in the development processing chamber 31 .
[0152] Next, the transport mechanism 137 takes out the substrate W after the thermal processing from a predetermined thermal processing unit PHP of the upper stage thermal processing portion 303 ( FIG. 4 ) using the hand H 1 . The transport mechanism 137 carries the substrate W after the development processing held by the hand H 2 to the thermal processing unit PHP. Then, the transport mechanism 137 places the substrate W taken out from the thermal processing unit PHP on the substrate platform PASS 6 ( FIG. 5 ).
[0153] The transport mechanism 137 repeats the foregoing processing to cause the plurality of substrates W to be successively subjected to the predetermined processing in the second processing block 13 .
[0154] The transport mechanism 138 performs the same operation as the transport mechanism 137 to carry the substrates W in and out of the substrate platforms PASS 7 , PASS 8 , the placement/buffer section P-BF 2 ( FIG. 5 ), the development processing chamber 33 ( FIG. 2 ), the coating processing chamber 34 ( FIG. 2 ) and the lower stage thermal processing portion 304 ( FIG. 3 ).
[0155] As described above, the substrates W transported by the transport mechanism 137 are processed in the development processing chamber 31 , the coating processing chamber 32 and the upper stage thermal processing portion 303 , and the substrates W transported by the transport mechanism 138 are processed in the development processing chamber 33 , the coating processing chamber 34 and the lower stage thermal processing portion 304 in the present embodiment. In this case, the plurality of substrates W can be simultaneously processed in the upper processing section (the development processing chamber 31 , the coating processing chamber 32 and the upper stage thermal processing portion 303 ) and the lower processing section (the development processing chamber 33 , the coating processing chamber 34 and the lower stage thermal processing portion 304 ). This improves throughput of the second processing block 13 without increasing the transport speed of the substrates W by the transport mechanisms 137 , 138 . The transport mechanisms 137 , 138 are provided one above the other, thus preventing an increase of footprint of the substrate processing apparatus 100 .
[0156] While the substrates W are subjected to the cooling processing in the cooling unit CP before the development processing of the substrates W in the development processing chamber 31 in the foregoing example, the substrates W may not be subjected to the cooling processing in the cooling unit CP before the development processing if the development processing can be properly performed.
[0157] (6-4) Operations of the Cleaning/Drying Processing Block 14 A and the Carry-In/Carry-Out Block 14 B
[0158] Description will be made of the operations of the cleaning/drying processing block 14 A and the carry-in/carry-out block 14 B mainly referring to FIGS. 5 and 7 .
[0159] In the cleaning/drying processing block 14 A, the transport mechanism 141 ( FIG. 7 ) takes out the substrate W after the edge exposure placed in the placement/buffer section P-BF 1 by the transport mechanism 137 ( FIG. 5 ) using the hand H 3 .
[0160] Next, the transport mechanism 141 takes out the substrate W after the cleaning processing and the drying processing from the predetermined cleaning/drying processing unit SD1 of the cleaning/drying processing section 161 ( FIG. 7 ) using the hand H 4 . The transport mechanism 141 carries the substrate W after the edge exposure held by the hand H 3 to the cleaning/drying processing unit SD1.
[0161] The transport mechanism 141 subsequently places the substrate W after the cleaning processing and the drying processing held by the hand H 4 in the placement/cooling section P-CP ( FIG. 5 ). In the placement/cooling section P-CP, the substrate W is cooled to a temperature suitable for the exposure processing in the exposure device 15 ( FIG. 1 ).
[0162] The transport mechanism 141 then takes out the substrate W after the edge exposure placed in the placement/buffer section P-BF 2 by the transport mechanism 138 ( FIG. 5 ) using the hand H 3 . The transport mechanism 141 then takes out the substrate W after the cleaning processing and the drying processing from the predetermined cleaning/drying processing unit SD1 of the cleaning/drying processing section 161 ( FIG. 7 ) using the hand H 4 . The transport mechanism 141 carries the substrate W after the edge exposure held by the hand H 3 in the cleaning/drying processing unit SD1. Next, the transport mechanism 141 places the substrate W after the cleaning processing and the drying processing held by the hand H 4 in the placement/cooling section P-CP ( FIG. 5 ). In this manner, the transport mechanism 141 alternately transports the substrates W after the edge exposure placed in the placement/buffer sections P-BF 1 , P-BF 2 to the placement/cooling sections P-CP via the cleaning/drying processing section 161 .
[0163] Here, the substrates W housed in the carrier 113 ( FIG. 5 ) are alternately transported to the substrate platforms PASS 1 , PASS 3 ( FIG. 5 ) by the transport mechanism 115 ( FIG. 5 ). In addition, the processing speed of the substrates W in the coating processing chambers 21 , 22 ( FIG. 2 ) and the upper stage thermal processing portion 301 ( FIG. 3 ) is substantially equal to that in the coating processing chambers 23 , 24 ( FIG. 2 ) and the lower stage thermal processing portion 302 ( FIG. 3 ).
[0164] Furthermore, the operation speed of the transport mechanism 127 ( FIG. 5 ) is substantially equal to that of the transport mechanism 128 ( FIG. 5 ). The processing speed of the substrates W in the development processing chamber 31 , the coating processing chamber 32 ( FIG. 2 ) and the upper stage thermal processing portion 303 ( FIG. 3 ) is substantially equal to that in the development processing chamber 33 , the coating processing chamber 34 ( FIG. 2 ) and the lower stage thermal processing portion 304 ( FIG. 3 ). The operation speed of the transport mechanism 137 ( FIG. 5 ) is substantially equal to that of the transport mechanism 138 ( FIG. 5 ).
[0165] As described above, the substrates W are alternately transported by the transport mechanism 141 ( FIG. 7 ) from the placement/buffer sections P-BF 1 , P-BF 2 ( FIG. 5 ) to the placement/cooling sections P-CP, so that the order of the substrates W carried from the carriers 113 into the substrate processing apparatus 100 coincides with the order of the substrates W transported from the cleaning/drying processing block 14 A into the placement/cooling sections P-CP ( FIG. 5 ). In this case, the processing history of each substrate W in the substrate processing apparatus 100 is easily controlled.
[0166] The transport mechanism 142 ( FIG. 7 ) takes out the substrate W after the exposure processing placed in the substrate platform PASS 9 ( FIG. 5 ) by the hand H 5 . Next, the transport mechanism 142 takes out the substrate W after the cleaning processing and the drying processing from the predetermined cleaning/drying processing unit SD2 of the cleaning/drying processing section 162 ( FIG. 7 ) using the hand H 6 . The transport mechanism 142 carries the substrate W after the exposure processing held by the hand H 5 in the cleaning/drying processing unit SD2.
[0167] Next, the transport mechanism 142 transports the substrate W after the cleaning processing and the drying processing held by the hand H 6 to the thermal processing unit PHP ( FIG. 7 ) of the upper stage thermal processing portion 303 . Post exposure bake (PEB) processing is performed in the thermal processing unit PHP.
[0168] The transport mechanism 142 ( FIG. 7 ) subsequently takes out the substrate W after the exposure processing placed on the substrate platform PASS 9 ( FIG. 5 ) using the hand H 5 . Next, the transport mechanism 142 takes out the substrate W after the cleaning processing and the drying processing from the predetermined cleaning/drying processing unit SD2 of the cleaning/drying processing section 162 ( FIG. 7 ) using the hand H 6 . The transport mechanism 142 carries the substrate W after the exposure processing held by the hand H 5 in the cleaning/drying processing unit SD2.
[0169] The transport mechanism 142 then transports the substrate W after the cleaning processing and the drying processing held by the hand H 6 to the thermal processing unit PHP ( FIG. 7 ) of the lower stage thermal processing portion 304 . The PEB processing is performed in the thermal processing unit PHP.
[0170] In this manner, the transport mechanism 142 alternately transports the substrates W after the exposure processing placed in the substrate platform PASS 9 to the upper stage thermal processing portion 303 and the lower stage thermal processing portion 304 via the cleaning/drying processing section 162 .
[0171] In the carry-in/carry-out block 14 B, the transport mechanism 146 ( FIG. 5 ) takes out the substrate W placed in the placement/cooling section P-CP using the hand H 7 , and transports the substrate W to the substrate carry-in section 15 a of the exposure device 15 . In addition, the transport mechanism 146 takes out the substrate W after the exposure processing from the substrate carry-out section 15 b of the exposure device 15 using the hand H 8 , and transports the substrate W to the substrate platform PASS 9 .
[0172] Here, as described above, the order of the substrates W placed in the placement/cooling sections P-CP ( FIG. 5 ) by the transport mechanism 141 ( FIG. 7 ) is equal to the order of the substrates W carried from the carriers 113 ( FIG. 5 ) into the substrate processing apparatus 100 . This allows the order of the substrates W carried from the carriers 113 into the substrate processing apparatus 100 to coincide with the order of the substrates W carried in the exposure device 15 by the transport mechanism 142 ( FIG. 7 ). Accordingly, the processing history of each substrate W in the exposure device 15 is easily controlled. In addition, variation in the state of the exposure processing among the plurality of substrates W carried from one carrier 113 to the substrate processing apparatus 100 can be prevented.
[0173] Note that when the exposure device 15 cannot receive the substrate W, the transport mechanism 141 ( FIG. 7 ) causes the substrates W after the cleaning processing and the drying processing to be temporarily housed in the placement/buffer sections P-BF 1 , P-BF 2 .
[0174] Moreover, when the development processing unit 139 ( FIG. 2 ) of the second processing block 13 cannot receive the substrate W after the exposure processing, the transport mechanisms 137 , 138 ( FIG. 5 ) cause the substrates W after the PEB processing to be temporarily housed in the placement/buffer sections P-BF 1 , P-BF 2 .
[0175] When the substrates W are not normally transported to the placement/buffer sections P-BF 1 , P-BF 2 due to malfunction or the like of the first and second processing blocks 12 , 13 , transportation of the substrates W from the placement/buffer sections P-BF 1 , P-BF 2 by the transport mechanism 141 may be temporarily stopped until the transportation of the substrates W is normalized.
[0176] (7) Details of the Placement/Buffer Sections
[0177] Next, description will be made of the detailed configurations of the placement/buffer sections P-BF 1 , P-BF 2 . FIGS. 8 and 9 are a perspective view and a side view showing the appearance of the placement/buffer section P-BF 1 . FIG. 10 is a plan view for explaining an operation of carrying the substrate W in and out of the placement/buffer section P-BF 1 . Note that the configuration of the placement/buffer section P-BF 2 is the same as that of the placement/buffer section P-BF 1 shown in FIGS. 8 to 10 .
[0178] As shown in FIGS. 8 and 9 , frames 911 , 912 extending in the vertical direction (the Z direction) are provided in a boundary portion between the second processing block 13 ( FIG. 1 ) and the cleaning/drying processing block 14 A. The placement/buffer section P-BF 1 has a pair of fixing members 91 extending in the vertical direction and a plurality of support plates 92 . The pair of fixing members 91 is attached to the frames 911 , 912 , respectively.
[0179] A plurality of convex portions 921 projecting in the transverse direction (the X direction) are provided in each fixing member 91 at regular intervals in the vertical direction. One ends of the plurality of support plates 92 are fixed to upper surfaces and lower surfaces of the convex portions 921 of one fixing member 91 , respectively, and the other ends of the plurality of support plates 92 are fixed to upper surfaces and lower surfaces of the convex portions 921 of the other fixing member 91 , respectively. This causes the plurality of support plates 92 to be horizontally arranged at equal intervals in the vertical direction.
[0180] A plurality of (three in this example) support pins 93 are provided on an upper surface of each support plate 92 . The substrate W is supported by the plurality of support pins 93 on each support plate 92 . In this manner, the plurality of substrates W can be housed in the placement/buffer section P-BF 1 .
[0181] As shown in FIG. 10 ( a ) to ( c ), the hands H 1 , H 2 of the transport mechanism 137 ( FIG. 5 ), the hands H 3 , H 4 of the transport mechanism 141 ( FIG. 7 ) and the hands H 5 , H 6 of the transport mechanism 142 ( FIG. 7 ) each have a substantially U-shape.
[0182] This allows the hands H 1 to H 6 of the transport mechanisms 137 , 141 , 142 to place the substrate W on the support pins 93 and receive the substrate W from a portion above the support pins 93 without interfering the frames 911 , 912 and the support pins 93 .
[0183] As described above, the placement/buffer section P-BF 1 is configured such that the substrates W can be carried in and out by the transport mechanisms 137 , 141 , 142 . Similarly, the placement/buffer section P-BF 2 is configured such that the substrates W can be carried in and out by the transport mechanisms 138 , 141 , 142 .
[0184] Note that the substrate platform PASS 9 ( FIG. 5 ) may be configured in the same manner as the placement/buffer sections P-BF 1 , P-BF 2 .
[0185] (8) Details of the Placement/Cooling Section
[0186] Description will be made of the detailed configuration of the placement/cooling sections P-CP. FIG. 11 is a perspective view showing the appearance of the placement/cooling sections P-CP. FIG. 12 is a diagram of the placement/cooling sections P-CP that are seen from the +X direction. FIG. 13 is a schematic transverse sectional view of the placement/cooling section P-CP. FIG. 14 is a schematic sectional view for explaining an operation of carrying the substrate W in and out of the placement/cooling section P-CP. FIGS. 11 and 12 show the three placement/cooling sections P-CP that are vertically stacked.
[0187] As shown in FIG. 11 , each placement/cooling section P-CP has a housing 95 . The housing 95 includes an upper surface portion 95 a, a lower surface portion 95 b, a front surface portion 95 c, a rear surface portion 95 d and side surface portions 95 e, 95 f. The upper surface portion 95 a and the lower surface portion 95 b are in parallel with the XY plane, and the front surface portion 95 c and the rear surface portion 95 d are in parallel with the YZ plane.
[0188] The side surface portions 95 e, 95 f extend along the XZ plane from both ends of the rear surface portion 95 d, respectively, and are bent inward so as to be close to each other to be integrated with both ends of the front surface portion 95 c, respectively.
[0189] A substrate carry-in opening 951 extending in the transverse direction is formed in the side surface portion 95 e, and a substrate carry-in opening 952 (see FIG. 13 , described below) extending in the transverse direction is formed in the side surface portion 95 f. As shown in FIG. 12 , a substrate carry-out opening 953 extending in the transverse direction (the Y direction) is formed in the rear surface portion 95 d.
[0190] As shown in FIG. 13 , a cooling plate 954 is provided inside each housing 95 . The cooling plate 954 is cooled by a cooling mechanism that is not shown. A plurality of (three in this example) support pins 955 are provided on the cooling plate 954 . The substrate W is placed on the support pins 955 .
[0191] Note that shutters for opening/closing the substrate carry-in openings 951 , 952 and the substrate carry-out opening 953 may be provided.
[0192] As shown in FIG. 14 ( a ), the hands H 3 , H 4 of the transport mechanism 141 ( FIG. 7 ) can enter the housing 95 from the substrate carry-in opening 951 , and place the substrate W on the support pins 955 . As shown in FIG. 14 ( b ), the hands H 5 , H 6 of the transport mechanism 142 ( FIG. 7 ) can enter the housing 95 from the substrate carry-in opening 952 , and place the substrate W on the support pins 955 .
[0193] As shown in FIG. 14 ( c ), the hands H 7 , H 8 of the transport mechanisms 146 ( FIG. 5 ) can enter the housing 95 from the substrate carry-out opening 953 , and hold and carry the substrate W on the support pins 955 out of the placement/cooling section P-CP.
[0194] In this manner, the placement/cooling section P-CP is configured such that the substrate W can be carried in and out by the transport mechanisms 141 , 142 and 146 .
[0195] As described above, the substrate W is carried in the placement/cooling section P-CP by the hand H 4 of the transport mechanism 141 in the present embodiment. The substrate W placed on the support pins 955 is cooled to the temperature suitable for the exposure processing by the cooling plate 954 . Then, the substrate W after the cooling processing is carried out of the placement/cooling section P-CP by the hand H 7 of the transport mechanism 146 ( FIG. 7 ).
[0196] (9) Effects of the Present Embodiment
[0197] (9-1)
[0198] The transport mechanism 141 can transport the substrates W among the placement/buffer sections P-BF 1 , P-BF 2 , the cleaning/drying processing section 161 and the placement/cooling sections P-CP, and the transport mechanism 142 can transport the substrates W among the placement/buffer sections P-BF 1 , P-BF 2 , the cleaning/drying processing section 162 , the thermal processing section 133 and the placement/cooling sections P-CP in the cleaning/drying processing block 14 A in the present embodiment.
[0199] This allows a wider choice of transport paths of the substrates W to be available in the cleaning/drying processing block 14 A. Accordingly, the substrates can be transported through optimum paths depending on how the substrates W are to be processed in the first and second processing blocks 12 , 13 and the cleaning/drying processing sections 161 , 162 . This allows transport efficiency of the substrates W to be increased, resulting in improved throughput.
[0200] (9-2)
[0201] In the present embodiment, the substrates W before the exposure processing are transported by the transport mechanism 141 , and the substrates W after the exposure processing are transported by the transport mechanism 142 in the cleaning/drying processing block 14 A. Moreover, the substrates W before the exposure processing are transported by the hand H 7 of the transport mechanism 146 , and the substrates W after the exposure processing are transported by the hand H 8 of the transport mechanism 146 in the carry-in/carry-out block 14 B.
[0202] In this manner, respective transport paths are independently ensured for the substrates W before the exposure processing and the substrates W after the exposure processing in the cleaning/drying processing block 14 A and the carry-in/carry-out block 14 B. In this case, the operations of the transport mechanisms 141 , 142 , 146 are more simplified than the case of complicated transport paths for the substrates W before the exposure processing and the substrates W after the exposure processing. This allows transport efficiency of the substrates W to be increased, resulting in improved throughput.
[0203] (9-3)
[0204] In the cleaning/drying processing block 14 A, the substrates W before the exposure processing are transported from the placement/buffer sections P-BF 1 , P-BF 2 to the placement/cooling sections P-CP via the cleaning/drying processing section 161 by the transport mechanism 141 , and the substrates W after the exposure processing are transported from the substrate platform PASS 9 to the upper stage thermal processing portion 303 or the lower stage thermal processing portion 304 via the cleaning/drying processing section 162 by the transport mechanism 142 . Moreover, the substrates W before the exposure processing are transported from the placement/cooling section P-CP to the exposure device 15 by the hand H 7 of the transport mechanism 146 , and the substrates W after the exposure processing are transported from the exposure device 15 to the substrate platform PASS 9 by the hand H 8 of the transport mechanism 146 in the carry-in/carry-out block 14 B.
[0205] Thus, the substrates W before the exposure processing and the substrates W after the exposure processing are not brought into indirect contact with one another in the cleaning/drying processing block 14 A and the carry-in/carry-out block 14 B. This prevents cross-contamination between the substrates W before the exposure processing and the substrates W after the exposure processing.
[0206] (9-4)
[0207] Furthermore, the respective transport paths are independently provided for the substrates W before the exposure processing and the substrates W after the exposure processing, so that the substrates W after the exposure processing can be smoothly transported to the thermal processing units PHP of the second processing block 13 .
[0208] Thus, the substrates W can be quickly subjected to the PEB processing after the exposure processing. As a result, a chemical reaction within the resist film can be immediately promoted to allow a desired exposure pattern to be obtained. In addition, a time period from the exposure processing to the PEB processing can be made substantially constant when the plurality of substrates W are successively processed. This results in prevention of variation in the accuracy of the exposure pattern.
[0209] (9-5)
[0210] Moreover, the transport mechanisms 137 , 141 , 142 can carry the substrates W in and out of the placement/buffer section P-BF 1 , and the transport mechanisms 138 , 141 , 142 can carry the substrates W in and out of the placement/buffer section P-BF 2 . Accordingly, the substrates W can be housed in the placement/buffer sections P-BF 1 , P-BF 2 at various timings before and after the exposure processing. As a result, timings at which the substrates W are transported by the transport mechanisms 137 , 138 , 141 , 142 can be easily adjusted.
[0211] Furthermore, the transport mechanisms 141 , 142 , 146 can carry the substrates W in and out of the substrate platform PASS 9 and the placement/cooling sections P-CP. In this case, the substrates W can be carried in and out of the placement/buffer sections P-BF 1 , P-BF 2 , the substrate platforms PASS 9 and the placement/cooling sections P-CP from three directions, so that the transport paths of the substrates W can be easily changed.
[0212] (9-6)
[0213] In the first and second processing blocks 12 , 13 , the plurality of substrates W can be concurrently processed in the processing section on the upper stage (the coating processing chambers 21 , 22 , 32 , the development processing chamber 31 ( FIG. 2 ), the upper stage transport chambers 125 , 135 ( FIG. 5 ) and the upper stage thermal processing portions 301 , 303 ( FIG. 3 )) and the processing section on lower stage (the coating processing chambers 23 , 24 , 34 , the development processing chamber 33 ( FIG. 2 ), the lower stage transport chambers 126 , 136 ( FIG. 5 ) and the lower stage thermal processing portions 302 , 304 ( FIG. 3 )).
[0214] Accordingly, the throughput of the first and second processing blocks 12 , 13 can be improved without increasing the transport speed of the substrates W by the transport mechanisms 127 , 128 , 137 , 138 . Moreover, the transport mechanisms 127 , 128 are provided one above the other and the transport mechanisms 137 , 138 are provided one above the other, thus preventing the increase of footprint of the substrate processing apparatus 100 .
[0215] (9-7)
[0216] The processing section on the upper stage and the processing section on the lower stage in the first and second processing blocks 12 , 13 have the equal configurations. Thus, even when a failure or the like occurs in one of the processing section on the upper stage and the processing section on the lower stage, the processing of the substrates W can be continued in the other processing section. This results in improved flexibility of the substrate processing apparatus 100 .
[0217] (9-8)
[0218] In the cleaning/drying processing units SD1, the substrates W before the exposure processing are subjected to the cleaning processing, so that part of components of the resist cover film on the substrates W are eluted to be washed. Therefore, even though the substrates W come in contact with a liquid in the exposure device 15 , the components of the resist cover film on the substrates W are hardly eluted in the liquid. Moreover, dust or the like adhering to the substrates W before the exposure processing can be removed. As a result, contamination in the exposure device 15 is prevented.
[0219] (9-9)
[0220] The liquid that has adhered to the substrates W during the cleaning processing is removed by subjecting the substrates W after the cleaning processing to the drying processing in the cleaning/drying processing units SD1, so that dust or the like in the atmosphere is prevented from again adhering to the substrates W after the cleaning processing. As a result, contamination in the exposure device 15 can be reliably prevented.
[0221] (9-10)
[0222] The substrates W after the exposure processing are subjected to the drying processing in the cleaning/drying processing units SD2, thereby preventing a liquid that has adhered to the substrates W during the exposure processing from dropping in the substrate processing apparatus 100 . In addition, the substrates W after the exposure processing are subjected to the drying processing to prevent dust or the like in the atmosphere from adhering to the substrates W after the exposure processing. Thus, contamination of the substrates W can be prevented.
[0223] The substrates W to which the liquid has adhered can be prevented from being transported to the substrate processing apparatus 100 to inhibit the liquid that has adhered to the substrates W during the exposure processing from affecting the atmosphere in the substrate processing apparatus 100 . This causes the temperature and humidity in the substrate processing apparatus 100 to be easily adjusted.
[0224] (9-11)
[0225] The liquid that has adhered to the substrates W during the exposure processing are prevented from adhering to the transport mechanisms 116 , 127 , 128 , 137 , 138 , 141 , 142 . Therefore, the liquid is prevented from adhering to the substrates W before the exposure processing. Thus, dust or the like in the atmosphere is prevented from adhering to the substrates W before the exposure processing, so that contamination of the substrate W is prevented. As a result, degradation in resolution performance at the time of the exposure processing can be prevented and contamination in the exposure device 15 can be prevented. In addition, components of the resist or components of the resist cover film can be reliably prevented from being eluted in the liquid that remains on the substrates W while the substrates W are transported from the cleaning/drying processing units SD2 to the development processing chambers 31 , 33 . This prevents deformation of the exposure patterns formed on the resist films. As a result, degradation in accuracy of line width during the development processing can be reliably prevented.
[0226] (10) Modifications
[0227] Description will be made of modifications of the above-described embodiment.
[0228] (10-1) First Modification
[0229] A first modification is described while referring to differences from the foregoing embodiment. FIG. 15 is a diagram showing the internal configuration of the cleaning/drying processing block 14 A in the first modification. Note that FIG. 15 is a diagram of the cleaning/drying processing block 14 A that is seen from the +X direction.
[0230] As shown in FIG. 15 , the plurality of (four in this example) cleaning/drying processing units SD1 are provided in each of the cleaning/drying processing sections 161 , 162 in the first modification.
[0231] One example of the transport paths of the substrates W in the cleaning/drying processing block 14 A of FIG. 15 is described mainly referring to FIGS. 5 and 15 .
[0232] The substrate W after the edge exposure placed in the placement/buffer section P-BF 1 by the transport mechanism 137 ( FIG. 5 ) is transported to a predetermined cleaning/drying processing unit SD1 of the cleaning/drying processing section 161 by the transport mechanism 141 ( FIG. 15 ). The substrate W subjected to the cleaning processing and the drying processing in the cleaning/drying processing unit SD1 of the cleaning/drying processing section 161 is transported to the placement/cooling section P-CP ( FIG. 5 ) by the transport mechanism 141 .
[0233] The substrate W after the edge exposure placed in the placement/buffer section P-BF 2 by the transport mechanism 138 ( FIG. 5 ) is transported to a predetermined cleaning/drying processing unit SD1 of the cleaning/drying processing section 162 by the transport mechanism 142 ( FIG. 15 ). The substrate W subjected to the cleaning processing and the drying processing in the cleaning/drying processing unit SD1 of the cleaning/drying processing section 162 is transported to the placement/cooling section P-CP ( FIG. 5 ) by the transport mechanism 142 .
[0234] The substrates W after the exposure processing placed in the substrate platform PASS 9 by the transport mechanism 146 ( FIG. 5 ) are transported to the thermal processing unit PHP of the upper stage thermal processing portion 303 and the thermal processing unit PHP of the lower stage thermal processing portion 304 by the transport mechanism 142 ( FIG. 15 )
[0235] As described above, the substrates W before the exposure processing are subjected to the cleaning processing and the drying processing in both the cleaning/drying processing sections 161 , 162 in the first modification. This improves the efficiency of the cleaning processing and the drying processing of the substrates W before the exposure processing. Accordingly, when the cleaning processing and the drying processing after the exposure processing are not required, a significant number of substrates W can be more quickly processed.
[0236] Note that the back surfaces and ends of the substrates W are subjected to the cleaning processing in some cases during the cleaning processing and the drying processing of the substrates W before the exposure processing, as described above. In the case, a processing time period is increased to degrade the throughput.
[0237] Therefore, the substrates W before the exposure processing are subjected to the cleaning processing and the drying processing in both the cleaning/drying processing sections 161 , 162 as described in this example, thereby suppressing the degradation of the throughput due to the increase of the processing time period.
[0238] In the first modification, one of the hands H 5 , H 6 may be used in transportation of the substrates W before the exposure processing by the transport mechanism 142 , and the other of the hands H 5 , H 6 may be used in transportation of the substrates W after the exposure processing by the transport mechanism 142 . In this case, the substrates W before the exposure processing and the substrates W after the exposure processing are prevented from coming in indirect contact with one another through the transport mechanism 142 . This inhibits cross-contamination between the substrates W before the exposure processing and the substrates W after the exposure processing.
[0239] (10-2) Second Modification
[0240] A second modification is described while referring to differences from the foregoing embodiment. FIG. 16 is a diagram showing the internal configuration of the cleaning/drying processing block 14 A in the second modification. Note that FIG. 16 is a diagram of the cleaning/drying processing block 14 A that is seen from the +X direction.
[0241] As shown in FIG. 16 , the plurality of (five in this example) cleaning/drying processing units SD2 are provided in each of the cleaning/drying processing sections 161 , 162 in the second modification.
[0242] One example of the transport paths of the substrates W in the cleaning/drying processing block 14 A of FIG. 16 is described mainly referring to FIGS. 5 and 16 .
[0243] The substrates W after the edge exposure placed in the placement/buffer sections P-BF 1 , P-BF 2 by the transport mechanisms 137 , 138 ( FIG. 5 ) are transported to the placement/cooling sections P-CP ( FIG. 5 ) by the transport mechanisms 141 , 142 ( FIG. 16 ).
[0244] The substrates W after the exposure processing placed in the substrate platform PASS 9 by the transport mechanism 146 ( FIG. 5 ) are transported to the cleaning/drying processing units SD2 of the cleaning/drying processing section 161 by the transport mechanism 141 ( FIG. 16 ) or transported to the cleaning/drying processing units SD2 of the cleaning/drying processing section 162 by the transport mechanism 142 .
[0245] The substrates W subjected to the cleaning processing and the drying processing in the cleaning/drying processing units SD2 of the cleaning/drying processing section 161 are transported to the substrate platform PASS 9 ( FIG. 5 ) by the transport mechanism 141 . The substrates W transported to the substrate platform PASS 9 are transported to the thermal processing units PHP of the upper stage thermal processing portion 303 or the thermal processing units PHP of the lower stage thermal processing portion 304 by the transport mechanism 142 ( FIG. 16 ).
[0246] The substrates W subjected to the cleaning processing and the drying processing in the cleaning/drying processing units SD2 of the cleaning/drying processing section 162 are transported to the thermal processing units PHP of the upper stage thermal processing portion 303 or the lower stage thermal processing portion 304 by the transport mechanism 142 .
[0247] In this manner, the substrates W after the exposure processing are subjected to the cleaning processing and the drying processing in both the cleaning/drying processing sections 161 , 162 in the second modification. This improves the efficiency of the cleaning processing and the drying processing of the substrates W after the exposure processing. Accordingly, when the cleaning processing and the drying processing before the exposure processing are not required, a significant number of substrates W can be more quickly processed.
[0248] In addition, one of the hands H 3 , H 4 may be used in transportation of the substrates W before the exposure processing by the transport mechanism 141 , the other of the hands H 3 , H 4 may be used in transportation of the substrates W after the exposure processing by the transport mechanism 141 , one of the hands H 5 , H 6 may be used in transportation of the substrates W before the exposure processing by the transport mechanism 142 , and the other of the hands H 5 , H 6 may be used in transportation of the substrates W after the exposure processing by the transport mechanism 142 in the second modification. In this case, the substrates W before the exposure processing and the substrates W after the exposure processing are prevented from coming in indirect contact with one another through the transport mechanisms 141 , 142 . This prevents cross-contamination between the substrates W before the exposure processing and the substrates W after the exposure processing.
[0249] (10-3) Third Modification
[0250] A third modification is described while referring to differences from the foregoing embodiment. FIG. 17 is a diagram showing the internal configuration of the cleaning/drying processing block 14 A in the third modification. Note that FIG. 17 is a diagram of the cleaning/drying processing block 14 A that is seen from the +X direction.
[0251] As shown in FIG. 17 , the plurality of (four in this example) cleaning/drying processing units SD1 are provided in the cleaning/drying processing section 161 , and one or a plurality of (one in this example) cleaning/drying processing unit SD1 and the plurality of (four in this example) cleaning/drying processing units SD2 are provided in the cleaning/drying processing section 162 in the third modification.
[0252] One example of the transport paths of the substrates W in the cleaning/drying processing block 14 A is described mainly referring to FIGS. 5 and 17 .
[0253] The substrates W after the edge exposure placed in the placement/buffer sections P-BF 1 , P-BF 2 by the transport mechanisms 137 , 138 ( FIG. 5 ) are transported to the cleaning/drying processing units SD1 of the cleaning/drying processing section 161 by the transport mechanism 141 ( FIG. 17 ) or transported to the cleaning/drying processing unit SD1 of the cleaning/drying processing section 162 by the transport mechanism 142 .
[0254] The substrates W subjected to the cleaning processing and the drying processing in the cleaning/drying processing units SD1 of the cleaning/drying processing section 161 are transported to the placement/cooling sections P-CP ( FIG. 5 ) by the transport mechanism 141 . Moreover, the substrates W subjected to the cleaning processing and the drying processing in the cleaning/drying processing unit SD1 of the cleaning/drying processing section 162 ( FIG. 17 ) are transported to the placement/cooling sections P-CP ( FIG. 5 ) by the transport mechanism 142 .
[0255] The substrates W after the exposure processing placed in the substrate platform PASS 9 by the transport mechanism 146 ( FIG. 5 ) are transported to the cleaning/drying processing units SD2 of the cleaning/drying processing section 162 by the transport mechanism 142 ( FIG. 17 ). The substrates W subjected to the cleaning processing and the drying processing in the cleaning/drying processing units SD2 of the cleaning/drying processing section 162 are transported to the thermal processing units PHP ( FIG. 17 ) of the upper stage thermal processing portion 303 or the lower stage thermal processing portion 304 by the transport mechanism 142 .
[0256] As described above, the substrates W before the exposure processing are subjected to the cleaning processing and the drying processing in both the cleaning/drying processing sections 161 , 162 , and the substrates W after the exposure processing are subjected to the cleaning processing and the drying processing in the cleaning/drying processing section 162 in the third modification.
[0257] As described above, the processing time period is increased when the back surfaces and ends of the substrates W are subjected to the cleaning processing during the cleaning processing and the drying processing of the substrates W before the exposure processing. Thus, a longer time period is required for the cleaning processing and the drying processing of the substrates W before the exposure processing than a time period required for the cleaning processing and the drying processing of the substrates W after the exposure processing. Therefore, as described in this example, the larger number of the cleaning/drying processing units SD1 than the number of the cleaning/drying processing units SD2 allows the substrates W before and after the exposure processing to be efficiently subjected to the cleaning processing and the drying processing.
[0258] The cleaning/drying processing unit SD1 is increased in size if a mechanism for subjecting the back surfaces and ends of the substrates W to the cleaning processing is provided in the cleaning/drying processing unit SD1. This inhibits provision of a large number of cleaning/drying processing units SD1 in the cleaning/drying processing section 161 . Therefore, the cleaning/drying processing unit SD1 is provided also in the cleaning/drying processing section 162 to ensure a sufficient number of cleaning/drying processing units SD1.
[0259] In the third modification, one of the hands H 5 , H 6 may be used in transportation of the substrates W before the exposure processing by the transport mechanism 142 , and the other of the hands H 5 , H 6 may be used in transportation of the substrates W after the exposure processing by the transport mechanism 142 . In this case, the substrates W before the exposure processing and the substrates W after the exposure processing are prevented from coming in indirect contact with one another through the transport mechanism 142 . This prevents cross-contamination between the substrates W before the exposure processing and the substrates W after the exposure processing.
[0260] (10-4) Other Modifications
[0261] Another unit may be provided instead of the cleaning/drying processing units SD1, SD2. For example, a unit for testing the presence/absence of contamination in the ends of the substrates W before and after the exposure processing may be provided, and a unit for testing states of the films on the substrates W before and after the exposure processing may be provided.
[0262] (11) Correspondences between Elements in the Claims and Parts in Embodiments
[0263] In the following paragraphs, non-limiting examples of correspondences between various elements recited in the claims below and those described above with respect to various preferred embodiments of the present invention are explained.
[0264] In the foregoing embodiments, the first and second processing blocks 12 , 13 are examples of a processing section, the interface block 14 is an example of an interface, the placement/buffer sections P-BF 1 , P-BF 2 are examples of a first placement section, the placement/cooling section P-CP and the substrate platform PASS 9 are examples of a second placement section, the cleaning/drying processing section 161 is an example of a first processing region, and the cleaning/drying processing section 162 is an example of a second processing region.
[0265] The hands H 3 , H 4 , H 7 of the transport mechanisms 141 , 146 are examples of a first substrate transport mechanism, the hands H 5 , H 6 , H 8 of the transport mechanisms 142 , 146 are examples of a second substrate transport mechanism, the cleaning/drying processing unit SD1 is an example of a cleaning processing unit, the cleaning/drying processing unit SD2 is an example of a drying processing unit, the cleaning/drying processing block 14 A is an example of a processing block, the carry-in/carry-out block 14 B is an example of a carry-in/carry-out block, the hands H 3 , H 4 of the transport mechanism 141 are examples of a first substrate holder, the hand H 7 of the transport mechanism 146 is an example of a second substrate holder, the hands H 5 , H 6 of the transport mechanism 142 are examples of a third substrate holder, the hand H 8 of the transport mechanism 146 is an example of a fourth substrate holder, the X direction is an example of a first direction, and the Y direction is an example of a second direction.
[0266] The coating processing chambers 32 , 34 and the development processing chambers 31 , 33 are examples of a plurality of processing chambers, the coating processing unit 129 and the development processing unit 139 are examples of a plurality of liquid processing units, the upper stage transport chamber 135 is an example of a first transport chamber, the lower stage transport chamber 136 is an example of a second transport chamber, the transport mechanisms 137 , 138 are examples of a plurality of transport mechanisms for transport chambers, the coating processing chamber 32 and the development processing chamber 31 are examples of a first processing chamber group, the coating processing chamber 34 and the development processing chamber 33 are examples of a second processing chamber group, the placement/buffer section P-BF 1 is an example of a first placement portion, the placement/buffer section P-BF 2 is an example of a second placement portion, the transport mechanism 137 is an example of a first in-chamber transport mechanism, and the transport mechanism 138 is an example of a second in-chamber transport mechanism.
[0267] As each of various elements recited in the claims, various other elements having configurations or functions described in the claims can be also used.
[0268] While preferred embodiments of the present invention have been described above, it is to be understood that variations and modifications will be apparent to those skilled in the art without departing the scope and spirit of the present invention. The scope of the present invention, therefore, is to be determined solely by the following claims. | A method for processing a plurality of substrates after forming a photosensitive film on each substrate includes carrying each substrate into a placement buffer including a plurality of supporters by a first transport mechanism; taking out each substrate from the placement buffer to an interface by a second transport mechanism; carrying each substrate into the exposure device; carrying each substrate out of the exposure device into the placement buffer by the second transport mechanism; taking out each substrate from the placement buffer to the processing section by the first transport mechanism; performing development processing on each substrate; making each substrate stand by at the placement buffer based on timing at which the exposure device can accept each substrate; and making each substrate stand by at the placement buffer based on timing at which the developing device can accept each substrate. | 8 |
BACKGROUND OF THE INVENTION
This invention relates to organizations for a two-wire 21/2D coincident current core memory comprised of an array of toroidal cores, each core having a bit line driven by half select current and a word select line driven by half select current, and more particularly to organization for bit select (Y drive) lines time shared to read for both drive and sense functions with cancellation of cross-coupled noise from word select (X drive) lines.
In a two-line 21/2D memory, selected X and Y drive lines are energized with half select current of the proper polarity for both read and write operations. Typically, the X line selects a word consisting of a number of bits, but first a number of Y drive lines are energized to select the bits. Thus, to read a word, the selected bit lines are energized, and after all ringing of the bit lines has subsided, the word line is energized. Both X and Y drive currents for each bit will have the same direction through the core to set it to the bit 0 state. If the core had previously stored a bit 1, the flux of the core being switched to a bit 0 reduces a pulse on its bit line. The bit line may thus be used as a sense line, provided noise from the word select pulse also induced into the bit line can be cancelled. There are three configurations commonly used for achieving that cancellation.
One configuration, shown in FIG. 1a, uses the same Y bit drive current to energize two bit lines L1 and L2 equally. One bit line passes through its cores in one direction relative to the X word drive line W1, and the other bit lines passes through its cores in the other direction. Since the word drive line passes through corresponding cores of both bit lines in the same direction, only one core is "selected" to receive coincident half select current for read, or write, of the same sense, i.e., direction through the core. The other core receives half select current in one direction, and the other half in the other direction, so it is not switched. The paired lines are connected to a differential sense amplifier 10 so that only the difference in the currents on the paired sense lines will be amplified. As a consequence, the effects of the X drive pulse in the two lines will cancel, and only the line with the selected core that is switched will have any uncancelled current pulse which is sensed and amplified as a bit 1. A memory system employing this configuration for common-mode signal rejection is disclosed by the inventor in U.S. Pat. No. 3,693,176.
A second configuration very similar to the first employs paired bit drive lines, but instead of placing the corresponding cores of two different words on the two different bit lines L1 and L2, they are placed on the same bit lines, and the word select line W1 is folded as shown in FIG. 1b so that the word select pulse cancels itself on the selected bit line. Another variation folds the bit lines instead, as shown in FIG. 1c. These folded-line arrangements have a significant packaging advantage (lower wire termination density) over the unfolded arrangement of balanced sense lines and word lines in FIG. 1a, which allows significant cost reduction.
In any of these arrangements, the sense amplifier 10 is preferably coupled to the bit drive lines by a balun transformer T1 shown in FIG. 2 for the arrangement of FIG. 1c. However, magnetic and capacitive coupling between word and bit lines with either of the folded or the unfolded arrangements is now inherently imbalanced, and such imbalance can be minimized only by elaborate packaging methods. What is required is an arrangement which does not require balanced magnetic and capacitive coupling, yet still permits selecting paired bit lines for reading out a word, one bit out of each pair of bit lines with cancelled X word drive current induced into the Y bit drive lines.
SUMMARY OF THE INVENTION
In accordance with the invention, bit lines of a two-line 21/2D coincident current magnetic core memory are arranged for reading to be physically in parallel with unused bit lines for balanced capacitive and inductive coupling between a word drive line and the parallel bit drive lines. Any noise signal in the selected bit line and its parallel unused bit lines are thus capacitively and inductively balanced for cancellation at the input of bit sense amplifiers. In one exemplary embodiment, the other unselected bit lines are paired dummy lines physically in parallel with selected bit lines connected to opposite ends of a sense transformer. The paired dummy lines are connected to opposite ends of a primary winding of a second transformer having its secondary winding in series with the secondary winding of the sense transformer. In a preferred embodiment, the physically parallel bit lines are two sets of paired and folded bit lines, only one set of which is selected by switching means to receive bit drive current. The unselected pair corresponds to the dummy lines of the exemplary embodiment. Diode switches are provided to automatically connect the unselected pair to opposite ends of the primary winding of the second transformer. The arrangement is otherwise the same as in the exemplary embodiment. The bit read out is sensed by a differential amplifier as the signal difference between the selected set. In another preferred embodiment, the physically parallel bit lines are only two in a set and both have the same word line. One bit line is selected to conduct half select current from a source at one end of the primary winding of a bit sensing transformer connected to a differential sense amplifier, but the other (unselected) bit line connected to the same half select current source is not. Instead, diode switching means automatically connects the unselected bit line to the other end of the primary winding of the sense transformer. This allows only a trickle of current through the unselected bit line so that its cores cannot be switched by the common X word drive line. In that manner, the differential voltage across the primary winding of the sense transformer consists of a signal with capacitively and magnetically induced noise from the X word drive line appearing as a common mode signal on both bit lines which cancel at the sense transformer.
The novel features of the invention are set forth with particularity in the appended claims. The invention will best be understood from the following description when read in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1a, 1b and 1c illustrate three prior art arrangements for two-wire 21/2D coincident current core memories.
FIG. 2 illustrates the manner in which a balun transformer is used to advantage to couple paired bit lines in the arrangement of FIG. 1C to a sense amplifier.
FIG. 3 exemplifies the manner in which the secondary winding of an anti-sense transformer is connected in series with the secondary winding of a balun transformer of FIG. 2 to couple word line induced noise from a dummy pair of lines, disposed parallel to a selected pair of bit lines, for cancellation in accordance with the present invention.
FIG. 4 illustrates a preferred arrangement for the concept illustrated in FIG. 3.
FIG. 5 is a diagram illustrating how the arrangement shown in FIG. 4 may be used to implement a full memory.
FIG. 6 shows waveforms useful in understanding the operation of the system shown in FIG. 5.
FIG. 7 illustrates another arrangement for cancellation of word line induced noise in a selected pair of bit lines without the need for an extra pair of bit lines.
DESCRIPTION OF PREFERRED EMBODIMENTS
Referring now to FIG. 3, it will be noted by comparing it to FIG. 2 that paired bit lines L1 and L2 are coupled by a balun transformer T1 to a differential sense amplifier 10 in the folded Y bit line arrangement as shown in FIG. 1c. (The same reference numerals are being retained in the various figures for corresponding elements in order to facilitate comparison and understanding). The difference in the arrangement of FIG. 3, which exemplifies the present invention, is that unused (dummy) sense lines DSL1 and DSL2 are placed in a physically parallel arrangement with the used bit drive lines L1 and L2. In a read operation, the Y (bit) select current I is turned on first. It divides about equally into the selected lines L1 and L2 of a memory array. The selected W (word) drive line W1 is then pulsed. Since the line W1 intersects only the line L1, it will switch only core 11 from a bit 1 to a bit 0 state because the half select X and half select Y currents pass through only that core in the same direction. (To select another word with line W1, the polarity of the word select pulse is reversed and only a core 12 is switched.) Switching a core induces a bit-1 signal in the bit line L1. If the selected core 11 had been storing a bit 0, a bit-0 signal is induced in the bit line L1 with some noise. A noise signal is also induced at the core 12 which is not switched even if it is storing a bit 1 because it does not receive half select current on the line L1 in the same direction. The noise signal (referred to hereinafter as crosstalk) includes core reversible flux as well as inductively and capacitively coupled components from the word select pulse on the line W1.
The differential sense signal S is detected by the differential sense amplifier 10 which is coupled to the paired lines L1 and L2 by the balun transformer T1 that rejects the common mode signal and presents the difference at the secondary winding of the transformer T1. A transformer T2 is used for common mode rejection of the signal on the dummy lines DSL1 and DSL2, and the output at the secondary winding of the transformer T2 is subtracted by adding it out of phase to the output of the sense transformer T1. Since the crosstalk from the word drive line is approximately the same in the dummy lines as in the used lines, the crosstalk portion of the sensed signal will be cancelled from the output of the sense amplifier 10.
It should be noted that a balun sense transformer T1 has two primary windings of the same number (N1) of turns, and the secondary winding usually has a larger number (N2) to provide a step-up transformer. The secondary winding of the transformer T2 also has the same number (N2) of turns for a balanced common mode rejection into the amplifier 10. Since the transformer T2 has only one primary winding, and the same step-up ratio is to be maintained as for the transformer T1, the primary winding of the transformer T2 has twice the number of turns as the primary windings of the transformer T1. In other words, the arrangement of one primary winding in the transformer T2 is the equivalent of the arrangement of two primary windings in the transformer T1.
In practice, a number of bit drive lines share the same sense transformer. There may also be a number of dummy lines for the bit drive lines. Multiplexing diode switches are then provided to make the necessary connections.
This exemplary embodiment shown in FIG. 3 has the advantages of folded Y-drive lines, but the same technique for cancellation of X-drive crosstalk could be used to equal advantage in the unfolded configuration of FIG. 1a. The problem in either case is that unused (dummy) lines must be provided, adding to the expense, bulk and weight of the memory. A preferred arrangement for practicing the present invention is therefore one shown in FIG. 4 which is like the arrangement of FIG. 3, except that the unused lines providing X-drive crosstalk cancellation are paired bit drive lines not being used for the selected word. Two sets of paired bit drive lines L1a, L2a and L1b, L2b are arranged to be physically parallel so that a line of one pair serves as the unused (dummy) line for a bit line selected from the other pair. Diodes 14 connected to a load resistor R L automatically switch the unselected pair of bit drive lines to primary windings of a balun transformer T22. (This type of transformer is here used to facilitate implementing the switching arrangement of the multiplexing diodes, but it is otherwise equivalent to the transformer T2 in FIG. 3.) Selection of one pair or the other of the lines is by Y-drive switch pair YD0 and switch pair YD1. Only one switch pair is turned on at a time to connect the paired lines L1a and L1b through switch pair YD0 or the paired lines L2a and L2b through the switch pair YD1 to the transformer T1.
In operation, a signal (typically five volts) at terminal YS0 selects all of the group of Y-drive lines connected at junction PTA, but only one pair of bit drive lines will conduct current as selected by the switch pairs YD0 and YD1. A source 16 provides the amplitude of current necessary to read. If switch pair YD0 is activated (closed), current flows in lines L1a and L1b. Diodes D1 and D2 are then forward biased, whereas diodes D3 and D4 are not. This is so because conduction through the lines L1a and L1b, as determined by the high impedance current source 16, drops the voltage on the anodes of the diodes D3 and D4 enough so that they are insufficiently forward biased to conduct. But switch pair YD1 is not conducting so that the +5 volts at the junction PTA applied to lines L2a and L2b will forward bias the diodes D1 and D2.
After the Y-drive current has become steady through the selected lines L1a and L1b, the selected word drive line W1 is pulsed. Only the core 11 will have half select current in the same direction in both X and Y lines to switch it. A small trickle of current flows through lines L2a and L2b adequate to forward bias diodes D1 and D2, but not enough to affect system operating margins. When that core 11 is switched, it induces a bit-1 pulse on the line L1a which is balanced with the line L1b so that it can be sensed, as described with reference to FIG. 2. But the word select line W1 crosses only the line L1a, so as to induce crosstalk in the line L1a and not L1b. This crosstalk would make sensing of the bit-1 signal more difficult, so it is cancelled by the crosstalk induced in the line L2a. It is thus clear that lines L1a and L2a are paired for crosstalk cancellation via transformer T22 while lines L1a and L1b are paired for balanced bit-drive of the sense transformer. Similarly, lines L1b and L2b are paired for crosstalk cancellation via transformer T22 while lines L2a and L2b are paired for balanced bit-drive of the sense transformer T1. The bit lines paired for crosstalk cancellation are physically parallel in approximately the same paths in the memory so they will have substantially the same capacitive and inductive crosstalk from the word drive line.
The preferred embodiment has been described with reference to FIG. 4 in a minimum arrangement, which is two paired lines L1a, L1b and L2a, L2b, each pair for common mode signal rejection of the Y drive current when selected, and the other pair for cancellation of crosstalk from the X drive line during a read cycle in accordance with this invention. For a better understanding of how a more complete memory may be organized for both read and write cycles, with the present invention implemented for a read cycle, reference is now made to FIG. 5.
To facilitate understanding how the arrangement of FIG. 4 is embodied in FIG. 5, the same reference numerals are maintained for the paired bit (Y) drive lines L1a, L1b and L2a, L2b. Two additional pairs L3a, L3b and L4a, L4b are added to the Y-sink terminal YS0. Each pair for common mode signal rejection is separated in the drawing to group all of the "a" lines together above, and all of the "b" lines together below since the "a" lines are connected to the bottom end of the balun sense transformer T1 when selected for use during a read cycle by the switch pair YD0 and the switch pair YD1 now shown with the pair YD0 separated into switches YD0Ra and YD0Rb, and the pair YD1 separated into switches YD1Ra and YD1Rb. The additional pairs L3a, L3b and L4a, L4b are arranged in a strictly analogous and symmetrically way as the first two pairs.
The symmetry of the selection switches at the sense transformer T1 and the multiplexing diodes 14 at the noise cancellation transformer T22 is maintained. The only difference as to the four pairs is that the "a" lines are shown above as a group, and the "b" lines are shown below as a group. This grouping is a natural arrangement because the "a" lines are crossed by one set of word drive lines while the "b" lines are crossed by another set of word drive lines. When a core in one group is to be read from one of the paired "a" and "b" lines, the other of the pulsed lines is used to provide common mode signal injection. All of the remaining "a" and "b" lines of unselected pairs grouped together in the "a" group and in the "b" group are physically parallel to each other in the "a" and "b" groups. In addition, all of the remaining "a" and "b" lines of unselected pairs are coupled to the crosstalk rejection transformer T22 where bit drive current in the unselected pairs cancel and the crosstalk signal is developed for subtraction from the sensed output into the amplifier 10.
It should be noted that the arrangement thus far described with reference to four pair of bit drive lines concerns only one bit of a word. Other identical arrangements are provided for other bits of a word, each arrangement with its own bit sense amplifier 10, but all sharing the same word select lines.
A second Y-sink terminal YS1 can be provided to accommodate another four pairs of bit drive lines L5a, L5b; L6a, L6b; L7a, L7b; and L8a, L8b. These four pairs time share the four paired V-drive read switches connected to the transformer T1, and the diode multiplexing switches connected to the transformer T22. Banks of isolation (buffer) diodes 18 and 20 prevent any Y-select current in a pair of bit drive lines selected from the YS0 terminal from energizing bit drive lines not selected from the YS1 terminal.
The banks of isolation diodes include not only one diode for each bit drive line connected to one of the Y-drive select switches for a read cycle, but also one diode for each bit drive line connected to Y-drive select switches for a write cycle shown in two groups of four, one "a" group labeled YD0Wa, YD1Wa, YD2Wa and YD3Wa, and one "b" group labeled YD0Wb, YD1Wb, YD2Wb and YD3Wb. A write cycle is executed in a conventional manner, and it does not include the transformers T1 and T22. For example, assume a core 22 is to be set to the "1" state in line L6a intersection by word line W3. The group of four bit drive lines that includes the line L6a is first selected by a negative pulse on the terminal YS1. Then shortly thereafter, the Y-drive switch YD1Wa is activated to provide negative half select current through the line L6a. While the terminal YS1 is still negative, and the switch YD1Wa is still activated, a terminal XS0 receives a positive pulse while a switch XD1Cb is activated to provide negative current through the word line W3, i.e., word select current in the same direction through the core 22 as the bit select current. The diode of the bank of isolation diodes 18 which connects the switch YD1Wa to the line L6a will conduct the necessary negative current, i.e., current from a source 24 to the terminal YS1, while all other diodes of the bank 18 are reverse biased and will therefore not conduct, thus isolating the current of the line L6a from all other bit lines connected to the terminal YS1. A bank 26 of buffer diodes similarly isolate one energized word line connected to a selectively activated terminal XS0 or XS1 from all other word lines.
Operation during a read cycle will now be described by way of a summary for the arrangement shown in FIG. 5. Assuming a core 28 is to be read, the bit line L2a is first selected by applying a positive pulse to the terminal YS0, and then activating the half select read current from the source 16 through the paired switches YD1Ra and YD1Rb as shown in FIG. 6 for the switch YD1Ra. Meantime, the XS0 terminal is made positive to charge the word select line W3, and thereafter a read pulse of proper polarity from a source 30 is transmitted through an activated switch XD1Cb. The core 28 then has two half select currents through it of the same polarity to switch it to the "0" state. FIG. 6 shows the XS0 voltage and the XD1Cb current pulse. The voltage of the word line W3 will be affected by the read pulse, as shown in FIG. 6. The result of this shift in voltage on the word drive line W3 is to affect shifts in the bit line L2a to the transformer T1 that is not cancelled by the paired line L2b due first to capacitive and then to inductive coupling of the word drive line L3 to the bit line drive L2a. There will also be a pulse on the line L2a if the core 28 was previously storing a bit 1 as it is switched to the "0" state, as shown by a dotted line over the waveform that shows crosstalk to the transformer T1. It can be readily appreciated that such crosstalk makes detection of the bit-1 pulse read out very difficult, if not impossible in some extreme crosstalk situations as that illustrated in FIG. 6. To cancel that crosstalk to the transformer T1, all of the other lines L1a, L3a and L4a connected to one side of the transformer T22, and all of the corresponding lines L1b, L2b and L4b connected in parallel to the other end of the transformer T22, produce crosstalk to the transformer T22 that is substantially the same as the crosstalk to the transformer T1, but in antiphase, so that when added in the secondary circuits of the transformers, the net voltage to the amplifier 10 is as shown in the last waveform, namely a zero (or reference) voltage with the bit-1 pulse, if any, superimposed. That bit-1 pulse can then be easily threshold detected at some level that will allow for some low amplitude noise to be tolerated.
In an alternative arrangement for cancellation of word drive line crosstalk in the circuit shown in FIG. 7, bit drive current is pulsed through one of two folded bit drive lines L1 and L2 which are physically parallel so that any crosstalk induced in one by a half-select pulse on the word drive line W is also induced in the other bit drive line. One of the two bit drive lines is selectively connected to the primary winding of a transformer T by activating one of two switches YD0 and YD1. If line L1 is selected, diode D1 is forward biased by the half-select bit pulse through the line L1 while the switch YD1 is held off. Diode D2 is not forward biased because the switch YD0 allows half-select current to flow through line L1, thus dropping the voltage on the anode of the diode D2 below the voltage on the anode of D1. The coincident half-select word (X) current will then switch one of the two cores on the selected bit drive line, depending upon the polarity selected for the X pulse, in the normal manner for a Y-folded bit drive line. As in the arrangement of FIG. 4, the line L2 paired with the line L1 for noise cancellation can be easily arranged so that capacitive and inductive crosstalk components from the word drive line will be approximately equal for both bit drive lines. Consequently, the differential voltage applied across the input of the transformer T will consist of only the pulse produced by the switching core. Any noise induced in the line L1 will also be induced in the line L2 and therefore appear only as a common mode signal rejected by the transformer T.
It should be noted that since the diode D1 is forward biased when the line L1 is selected, there is current in the line L2, but it is not sufficient current for one of its two cores to be switched by the X pulse. This arrangement is the same in that respect as the arrangement of FIG. 4. What is different is that an unused line is not paired with the selected line for balancing the half-select current in the selected line, but since the bit drive current is steady at the time the X pulse is applied to switch the core, the detection of a bit 1 read out of a core will be possible, and made easier by cancellation of crosstalk. The advantage of this arrangement is its simplicity and lower cost, even considering an optimum voltage source 32 shown which will simplify the design of the transformer T and the associated dc-restore and sense circuits. The voltage source can be implemented by use of resistors, Zener diodes or other means.
Although particular embodiments of the invention have been described and illustrated herein with reference to folded bit lines, it is recognized that the invention may be practiced with unfolded bit lines, and that other modifications and equivalents may readily occur to those skilled in this art. Consequently, it is intended that the claims be interpreted to cover such modifications and equivalents. | Organizations are disclosed for driving bit lines of a two-line 21/2D coincident current magnetic core memory in which a bit line not used for reading a bit out of a core is placed physically in parallel with the bit line driven by half select current to approximate in the unused line the capacitive and inductive coupling of the driven line with the word drive line. That coupling produces in the unused line the same noise (crosstalk) produced in the driven bit line by the word drive pulse. The crosstalk signal in the unused line is subtracted from the signal in the driven bit line before amplification and detection. The unused line may be a separate dummy line, or simply another bit line not being used for the bit being read out. In the case of paired bit lines used for common mode rejection of the bit drive signal, a second pair of unused bit lines is arranged in parallel for crosstalk cancellation. | 6 |
REFERENCE TO RELATED APPLICATIONS
This application is a divisional of U.S. Ser. No. 377,314 filed May 12, 1982 (now U.S. Pat. No. 4,492,716), which, in turn, is a divisional of U.S. Ser. No. 177,889 filed Aug. 14, 1980 (now abandoned).
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a method of making a non-single-crystalline semiconductor layer on a substrate, and more particularly to a non-single-crystalline semiconductor layer manufacturing method which is of particular utility when employed in the fabricatian of a semiconductor photoelectric conversion device which may be used as a solar battery.
2. Description of the Prior Art
A semiconductor photoelectric conversion device using a non-single-crystalline semiconductor layer composed of amorphous or semi-amorphous semiconductor layers has now been taken notice of because the non-single-crystalline semiconductor layer may be formed thin, that is, the semiconductor material needed is small in amount and because the photoelectric conversion efficiency can be enhanced, as compared with a semiconductor photoelectric conversion device employing a single crystal or polycrystalline semiconductor.
The following method has heretofore been proposed for forming a non-single-crystalline semiconductor layer on a substrate.
The substrate is disposed in a reaction chamber having a gas inlet and a gas outlet, and a mixture gas including at least a semiconductor material gas and a carrier gas is introduced into the reaction chamber in such a state that a gas in the reaction chamber is exhausted through the gas outlet. An electromagnetic field is applied to the mixture gas to ionize it into a plasma, thereby to deposit a semiconductor material on the substrate. In this case, the atmospheric pressure in the reaction chamber is held below 1 atm and the substrate is maintained at a temperature lower than that at which the semiconductor material deposited on the substrate is formed as a crystalline semiconductor layer, thereby to obtain a desired non-single-crystalline semiconductor layer on the substrate.
With the conventional method, the substrate is usually disposed in that region of the reaction chamber in which the mixture gas plasma is produced. In this case, however, it is very difficult to form the mixture gas plasma homogeneously over the entire surface of the substrate in the reaction chamber because of the plasma forming mechanism.
Accordingly, the prior art method is defective in that the non-single-crystalline semiconductor layer formed on the substrate has many voids and is unhomogeneous in the direction of the plane of the semiconductor layer. Further, even if non-single-crystalline semiconductor layers are formed concurrently and individually on a number of substrates placed in the reaction chamber, the non-single-crystalline semiconductor layers are inevitably subject to dispersion in property; consequently, the conventional method is incapable of mass production of non-single-crystalline semiconductor layers of good quality.
Moreover, in the conventional method, the electromagnetic field for ionizing the mixture gas into a plasma is usually a DC electromagnetic field or a low-frequency electromagnetic field, so that the ratio in which the mixture gas is ionized into the plasma is very low, for example, below 1%.
Therefore, relatively much time is needed for forming a non-single-crystalline semiconductor layer to a required thickness on the substrate. Further, the mixture gas which is not ionized into a plasma is discharged without being used; this is a waste of the mixture gas. In general, a semiconductor hydride or halide gas is used as the semiconductor material gas in the mixture gas. For example, in the case of forming a non-single-crystalline semiconductor layer of silicon on the substrate, an SiH 4 (silane) gas is used as the above said semiconductor material gas. Such SiH 4 gas is ionized into a plasma of silicon and a plasma of hydrogen. According to the prior art method, since the electric field for ionizing the mixture is a DC or low-frequency electric field, the plasma of hydrogen is small in mass and hence is relatively small in kinetic energy. On the other hand, the plasma of silicon is large in mass and hence is relatively large in kinetic energy. The fact. that the kinetic energy of the plasma of silicon is large means that damage is imposed on a non-single-crystalline semiconductor Si layer in the course of its formation on the substrate while depositing thereon silicon. Further, the fact that the kinetic energy of the plasma of hydrogen is small means that it does not easily enter into the layer; therefore the effect of neutralizing dangling bonds in the layer is not sufficient.
Accordingly, the conventional method is incapable of making of non-single-crystalline, semiconductor layer of good quality.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide a novel non-single-crystalline semiconductor layer manufacturing method which is free from the above-said defects of the prior art.
The method of making the non-single-crystalline semiconductor layer of the present invention employs a reaction chamber provided with a gas inlet and a gas outlet.
According to an aspect of the present invention, a substrate is disposed in the reaction chamber, and a mixture gas containing at least a semiconductor material gas is introduced into the reaction chamber through the gas inlet thereof in such a state in which the gas in the reaction chamber is exhausted therefrom through the gas outlet. In this case, in the reaction chamber, an ionizing, high-frequency electromagnetic field of 1 GHz or more is applied to the mixture gas to ionize into a mixture gas plasma and the mixture gas plasma is passed into the reaction chamber by discharging the gas in the reaction chamber and, in the reaction chamber, a semiconductor material is deposited on the substrate as a result of the flowing of the mixture gas plasma into the reaction chamber, and in this case, the atmospheric pressure in the reaction chamber is held below 1 atm and the temperature of the substrate is maintained lower than that of single-crystallizing the semiconductor material deposited on the substrate, thereby to form a non-single-crystalline semiconductor layer on the substrate.
In accordance with the method of the present invention, the mixture gas plasma is formed in the reaction chamber and then passed through the reaction chamber. Therefore, in the reaction chamber the mixture gas plasma is substantially homogeneous throughout it. And the substrate is placed in the reaction chamber filled with such a substantially homogeneous mixture gas plasma is provided.
Accordingly, the method of the present invention has the advantage that the non-single-crystalline semiconductor layer deposited on the substrate can be obtained as a non-single-crystalline semiconductor layer which has substantially no or a negligibly small number of voids and is homogeneous in the direction of its plane. Moreover, even if non-single-crystalline semiconductor layers are formed concurrently and individually on a number of substrates placed in the reaction chamber, no dispersion is introduced in their property; accordingly, this provides the advantage that non-single-crystalline semiconductor layers of good quality can be mass-produced.
Moreover, since the method of the present invention employs a high-frequency electromagnetic field for ionizing the mixture gas into the mixture gas plasma, the ratio of ionizing the mixture gas into the mixture gas plasma is far higher than in the case of the priorart method. The ratio is, for example above 20%.
Accordingly, the non-single-crystalline semiconductor layer of a required thickness can be formed in a short time and the mixture gas can be used efficiently. Moreover, according to the method of this invention, a semiconductor hydride gas may be used as the semiconductor material gas in the mixture gas. Such a semiconductor gas is ionized into a plasma of semiconductors and a plasma of hydrogen. In this case, since the electric field for ionizing the mixture gas is the high-frequency electric field above 1 GHz, the plasma of hydrogen is small in mass and hence is relatively large in kinetic energy. On the other hand, the plasma of semiconductors are large in mass and hence is relatively small in kinetic enregy. The fact that the kinetic energy of the plasma of semiconductors are small means that no damage is imposed on a non-single-crystalline semiconductor layer in the course of its formation on the substrate while depositing thereon semiconductor. Further, the fact that the kinetic energy of the plasma of hydrogen is large means that it easily enters into the layer to neutralize dangling bonds therein. Since the mass of the plasma of hydrogen is light, no damage is imposed on the layer. Accordingly, the layer is formed with good quality.
Accordingly, the method of the present invention is advantageous in that the resulting non-single-crystalline semiconductor layer is free from voids and homogeneous in the direction of its surface.
Furthermore, the method of the present invention exhibits the advantage that a homogeneous, non-crystalline semiconductor layer can easily be obtained.
Other objects, features and advantages will become more apparent from the following description taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic diagram illustrating an embodiment of the non-single-crystalline semiconductor manufacturing method of the present invention and an example of the arrangement used therefore;
FIG. 2 is a schematic diagram showing another embodiment of the present invention and an example of the arrangement therefore; and
FIG. 3 is a schematic diagram showing still another embodiment of the present invention and an example of the arrangement therefor.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 illustrates an embodiment of the non-single-crystalline semiconductor layer manufacturing method of the present invention and an arrangement therefore, in which a reaction chamber 1 is employed.
The reaction chamber 1 has a gas inlet 2, a gas ionizing region 3, a semiconductor depositing region 4, and a gas outlet 5 which are provided in this order. The gas ionizing region 3 has a smaller effective cross-section than the semiconductor depositing region 4. Arranged around the gas ionizing region 3 is an ionizing high-frequency power source 6 which applies to the gas ionizing region 3 an ionizing high-frequency electromagnetic field of, for example, as 1 to 10 GHz, preferably 2.46 GHz. The high-frequency power source 6 may be formed by a microwave guide tube which is supplied with a high-frequency power, i.e. micro-wave power.
Disposed around the semiconductor depositing region 4 of the reaction chamber 1 is an orientating-accelerating high-frequency power source 9 which applies to the semiconductor depositing region 4 an orientating-accelerating electric field perpendicularly to the surfaces of the substrates 7. The electric field has a relatively low alternating frequency, for example, 1 to 100 MHz, preferably 13.6 MHz. The high-frequency power source 9 may be formed by a coil which is supplied with a high-frequency current. The high-frequency power source 9 is covered with a heating source 10 which heats the semiconductor depositing region 4 and consequently the substrates 7. The heating source 10 may be a heater which is supplied with a direct current.
To the gas inlet 2 of the reaction chamber 1 is connected one end of a mixture gas supply pipe 11, to which are connected a main semiconductor material compound gas source 17, an N type impurity compound gas source 18, a P type impurity compound gas source 19, an additional semiconductor material compound gas source 20 and a carrier gas source through control valves 12, 13, 14, 15 and 16, respectively. From the main semiconductor material compound gas source 17 is supplied a main-semiconductor material compound gas A such as a main semiconductor material hydride gas, a main semiconductor material halide gas, a main semiconductor material organic compound gas or the like. The main semiconductor material gas A is, for example, a silane (SiH 4 ) gas, a dichlorosilane (SiH 2 Cl 2 ) gas, a trichlorosilane (SiHCl 3 ) gas, silicon tetrachloride (SiCl 4 ) gas, a silicon tetrafluoride (SiF 4 ) gas or the like. From the N type impurity compound gas source 18 is supplied an N type impurity compound gas B such as an N type impurity hydride gas, an N type impurity halide gas, N type impurity hydroxide gas or the like, for example, a hydride, halide or hydroxide gas of nitrogen, phosphorus, arsenic, antimony, tellurium, or the like. The N type impurity compound gas B is, for example, a phosphine (PH 3 ) gas, an arsine (AsH 3 ) gas or the like. From the P type impurity compound gas source 19 is supplied a P type impurity compound gas C such as a P type impurity hydride gas, a P type impurity hydroxide gas, a P type impurity halide gas or the like. The P type impurity compound gas C is, for example, a hydride, hydroxide or halide gas of boron, aluminum, gallium, indium or the like. For instance, a diborane (B 2 H 6 ) gas is supplied from the P type impurity compound gas source 19. From the additional semiconductor material compound gas source 20 is supplied an additional semiconductor material compound gas D such as an additional semiconductor material hydroxide or halide gas of nitrogen, germanium, carbon, tin, lead or the like, for example, an SnCl 2 , SnCl 4 , Sn(OH) 2 , Sn(OH) 4 , PbCl 2 , PbCl 4 , Pb(OH) 2 , Pb(OH) 4 or like gas. From the carrier gas source 21 is supplied a carrier gas E which is a gas composed of or contains a helium (He) and/or neon (Ne) gas, for example, a gas composed of the helium gas, a neon gas, or mixture gas of the helium gas or the neon gas and a hydrogen gas.
To the gas outlet 5 of the reaction chamber 1 is connected one end of a gas outlet pipe 22, which is connected at the other end to an exhauster 24 through a control valve 23. The exhauster 24 may be a vacuum pump which evacuates the gas in the reaction chamber 1 through the control valve 23 and the gas outlet tube 22.
It is preferred that a gas homogenizer 25 is provided midway between the gas ionizing region 3 and the semiconductor depositing region 4 in the reaction chamber 1.
In the semiconductor depositing region 4 of the reaction chamber 1 there are placed a plurality of parallel substrates 7 planted on a boat 8 as of quartz.
The substrates 7 may be conductive metal substrates as of stainless steel, titanium, titanium nitride or the like; semiconductor substrates as of silicon, silicon oxide, germanium or the like; insulating substrates as of alumina, glass, epoxy resin, polyimido resin or the like; substrates, each having a tin oxide, indium oxide, titanium oxide or like light transparent, conductive oxide layer formed on an insulating base plate; substrates, each having a conductive metal layer formed on an insulating base plate; or substrates, each having an N or P type semiconductor layer in a single or multi-layer form on an insulating base plate.
As described above, the substrates 7 are placed in the semiconductor depositing region 4 of the reaction chamber 1 and, in the state in which the gas in the reaction chamber 1 is exhausted by the exhauster 24 through the gas outlet 5, the gas outlet pipe 22 and the control valve 23, a mixture gas F containing at least the main semiconductor material compound gas A available from the main semiconductor material compound gas source 17 via the control valve 12 and the carrier gas F available from the carrier gas source 21 via the control valve 16 is introduced into the gas ionizing region of the reaction chamber 1 via the gas inlet 2. In this case, the mixture gas F may contain the N type impurity compound gas B available from the N type impurity compound gas source 18 via the control valve 13 or the P type impurity compound gas C available from the P type impurity compound gas source 19 via the control valve 14. Further, the mixture gas F may also contain the additional semiconductor material compound gas available from the additional semiconductor material compound gas source 20 via the control valve 15. The amount of the carrier gas E contained in the mixture gas F may be 5 to 99 flow rate %, in particular, 40 to 90 flow rate % relative to the mixture gas F.
A high-frequency electromagnetic field is applied by the ionizing, high-frequency power source 6 to the mixture gas F introduced into the gas ionizing region 3, by which the mixture gas F is ionized into a plasma, thus forming a mixture gas plasma G in the gas ionizing region 3. In this case, the high-frequency electromagnetic field may be one that has a 10 to 300 W high-fequency energy having a frequency of 1 to 100 GHz, for example, 2.46 GHz.
Since the electromagnetic field employed for ionizing the mixture gas F into the mixture gas plasma G in the gas ionizing region 3 is a micro-wave electromagnetic field and has such a high frequency as mentioned above, the ratio of ionizing the mixture gas F into the mixture gas plasma G is high. The mixture gas plasma G contains at least a carrier gas plasma into which the carrier gas contained in the mixture gas F is ionized and a main semiconductor material compound gas plasma into which the semiconductor compound gas is ionized. Since the carrier gas contained in the mixture gas F is a gas composed of or containing the helium gas and/or the neon gas, it has a high ionizing energy. For example, the helium gas has an ionizing energy of 24.57 eV and the neon gas an ionizing energy of 21.59 eV. In contrast thereto, hydrogen and argon employed as the carrier gas in the conventional method have an ionizing energy of only 10 to 15 eV. consequently, the carrier gas plasma contained in the mixture gas plasma has a large energy. Therefore, the carrier gas plasma promotes the ionization of the semiconductor material compound gas contained in the mixture gas F. Accordingly, the ratio of ionizing the semiconductor material compound gas contained in the mixture gas into the semiconductor material compound gas plasma is high.
Consequently, the flow rate of the semiconductor material compound gas plasma contained in the mixture gas plasma G formed in the gas ionizing region 3 is high relative to the flow rate of the entire gas in the gas ionizing region 3.
The same is true of the case where the additional semiconductor material compound gas D, the N type impurity compound gas B or P type impurity compound gas C is contained in the mixture gas F and ionized into its gas plasma.
The mixture gas plasma G thus formed is flowed into the semiconductor depositing region 4 through the gas homogenizer 25 by exhausting the gas in the reaction chamber 1 by means of the exhauster 24 through the gas outlet 5, the gas outlet pipe 22 and the control valve 23.
By flowing the mixture gas plasma G into the semiconductor depositing region 4, a semiconductor material is deposited on the substrates 7 placed in the semiconductor depositing region 4. In this case, the flow rate of the mixture gas F introduced into the reaction chamber 1, especially the flow rate of the carrier gas E contained in the mixture gas F is controlled beforehand by the adjustment of the control valve 16 and the flow rate of the gas exhausted from the reaction chamber 1 through the gas outlet 5 is controlled in advance by adjustment of the control valve 23, by which the atmospheric pressure in the reaction chamber 1 is held below 1 atm. Moreover, the substrates 7 are maintained at a relatively low temperature under a temperature at which semiconductor layers deposited on the substrates become crystallized, for example, in the range from the room temperature to 700° C. In the case of maintaining the substrates at room temperature, the heating source 10 need not be used, but in the case of holding the substrate at a temperature higher than the room temperature, the heating source 10 is used to heat the substrates 7. Furthermore, the deposition of the semiconductor material on the substrates 7 is promoted by the orientating-accelerating electric field established by the orientating-accelerating high-frequency source 9 in a direction perpendicular to the surfaces of the substrates 7.
As described above, by depositing the semiconductor material on the substrates 7 in the semiconductor depositing region 4 in the state in which the atmospheric pressure in the reaction chamber 1 is held low and the substrates 7 are held at a relatively low temperature, desired non-single crystalline semiconductor layers are formed on the substrates 7.
In this case, the mixture gas plasma in the semiconductor depositing region 4 is the mixture plasma having flowed thereinto from the gas ionizing region 3, and hence is substantially homogeneous in the semiconductor depositing region 4. Consequently, the mixture gas plasma is substantially homogeneous over the entire surface of each substrate 7.
Accordingly, it is possible to obtain on each substrate 7 a non-single-crystalline semiconductor layer which is homogeneous in the direction of its surface and has substantially no or a negligibly small number of voids. Moreover, even if non-single-crystalline semiconductor layers are individually formed on a number of substrates 7 concurrently as shown, the non-single-crystalline semiconductor layers can be made without dispersion in their property; accordingly, non-single-crystalline semiconductor layers of good quality can be mass produced.
In addition, since the flow rate of the semiconductor material compound gas plasma contained in the mixture gas plasma G formed in the gas ionizing region 3 is large with respect to the flow rate of the entire gas in the gas ionizing region 3, as mentioned previously, the flow rate of the semiconductor material compound gas plasma contained in the mixture gas on the surface of each substrate 7 in the semiconductor depositing region 4 is also large relative to the flow rate of the entire gas on the surface of the substrate 7. This ensures that the non-single-crystalline semiconductor regions deposited on the surface of the semiconductor 7 has substantially no or a negligibly small number of voids and is homogeneous in the direction of the surface of the substrate 7.
Besides, since the carrier gas plasma contained in the mixture gas plasma formed in the gas ionizing region 3 has a large ionizing energy, as referred to previously, the energy of the carrier gas plasma has a large value when and after the mixture gas plasma flows into the semiconductor depositing region 4, and consequently the energy of the semiconductor material compound gas plasma contained in the mixture gas p1asma on the substrate 7 in the semiconductor depositing region 4 has a large value. Accordingly, the non-single-crystalline semiconductor layer can be deposited on the substrate 7 with high density.
Furthermore, the carrier gas plasma contained in the mixture gas plasma is composed of or includes the helium gas plasma and/or the neon gas plasma, and hence has a high thermal conductivity. Incidentally, the helium gas plasma has a thermal conductivity of 0.123 Kcal/mhr° C. and the neon gas plasma 0.0398 Kcal/mhr° C. Accordingly, the carrier gas plasma greatly contributes to the provision of a uniform temperature distribution over the entire surface of the substrate 7. As a consequence, the non-single-crystalline semiconductor layer deposited on the substrate 7 can be made homogeneous in the direction of its surface.
Moreover, since the carrier gas plasma contained in the mixture gas in the semiconductor depositing region 4 is a gas plasma composed of or containing the helium gas plasma and/or the neon gas plasma, the helium gas plasma is free to move in the non-single-crystalline semiconductor layer formed on the substrate 7. This reduces the density of recombination centers which tends to be formed in the non-single-crystalline semiconductor layer, ensuring to enhance its property.
In accordance with the above embodiment of the present invention, it is possible to form on the substrate 7 a non-single crystalline semiconductor layer which has substantially no voids or, if any, a negligibly small number of voids and is homogeneous in the direction of its surface. That is, for example, a non-single-crystalline silicon layer can be formed on the substrate; further, an N type, non-single-crystalline silicon layer can also be formed which contains an N type, impurity as of nitrogen, phosphorus, arsenic, antimony or tellurium may also be formed; moreover, a P type, non-single-crystalline silicon layer can also be formed which contains a P type impurity as of boron, aluminum, gallium or indium; furthermore, a non-single-crystalline compound semiconductor layer can also be formed which is composed of, for example, silicon and nitrogen, germanium, carbon, tin or lead; in addition, a non-single-crystalline compound semiconductor layer can also be formed which is composed of, for example, Si 3 N 4-x (0>x>4), Si x Ge 1-x (0>x>1), Si x C 1-x , (0>x>1), Si x Sn 1-x (0> x>1) or Si x Pb 1-x (0>x>1); besides, an N or P type, non-single-crystalline compound semiconductor layer can also be formed in which the above-said non-single-crystalline compound semiconductor layer contains the abovesaid N or P type impurity. It is also possible to form a non-single-crystalline compound semiconductor layer whose composition ration continuously varies in its thickwise direction. Furthermore, it is also possible to form a non-single-crystalline semiconductor layer whose composition ratio continuously varies from the composition ratio of a silicon layer to that of a non-single-crystalline compound semiconductor layers. Also it is possible to form a non-single-crystalline semiconductor layer which has formed therein one or more PN or hetero junctions.
According to the method of the present invention described above, the non-single-crystalline semiconductor layer is formed in the presence of the helium gas plasma and/or the neon gas plasma, and hence is annealed. If necessary, however, the non-single-crystalline semiconductor layer thus annealed may also be further annealed, using the helium gas plasma and/or neon gas plasma alone.
Next, another embodiment of the non-single-crystalline semiconductor layer manufacturing method of the present invention will be described with reference to FIG. 2 which illustrates an example of the apparatus for use in this embodiment. In FIG. 2, parts corresponding to those in FIG. 1 are identified by the same reference numerals. The illustrated apparatus, though not described in detail, is identical in construction with the apparatus of FIG. 1 except in that the orientating-accelerating high-frequency source 9 disposed around the semiconductor depositing region 4 is omitted, in that a plurality of pairs of substrates 7 assembled together facing in opposite directions are disposed in parallel in the semiconductor depositing region 4 of the reaction chamber 1, in that a mesh- , grid- or blind- like electrode 31 is disposed between adjacent pairs of substrates 7 in parallel therewith, and in that an orientating-accelerating DC power source 32 is connected between the electrodes 31 and the pairs of substrates 7 via the boat 8 to set up an orientating-accelerating DC electric field perpendicular to the surface of each substrate 7. In this case, the boat 8 and each pair of substrates 7 are conductive or provided with a conductive layer so that they may be electrically connected with the orientating-accelerating DC power source 32.
In exactly the same manner as described previously in conjunction with FIG. 1, the mixture gas F containing at least the semiconductor material compound gas A and the carrier gas E is introduced via the gas inlet 2 into the gas ionizing region 3 of the reaciton chamber 1 while exhausting the gas in the reaction chamber 1.
The high-frequency electromagnetic field set up by the high-frequency power source 6 is applied to the mixture gas F to ionize it into a plasma, as described previously in connection with FIG. 1. As a result of this, the mixture gas plasma G is formed in the gas ionizing region 3.
Then, the mixture gas plasma G thus formed is flowed into the semiconductor depositing region 4 as in the case of the embodiment of FIG. 1, by which the semiconductor material is deposited on the surface of each substrate 7. In this case, as in the same manner as set forth previously in respect of FIG. 1, the atmospheric pressure in the reaction chamber 1 is held low and the substrates 7 are maintained at a relatively low temperature, whereby non-single-crystalline semiconductor layers are formed on the substrates 7. In this case, however, by the orientating-accelerating DC electric field set up by the orientating-accelerating DC power source 32 in a direction perpendicular to the surface of each substrate 7, the mixture gas plasma in the semiconductor depositing region 4 is oriented towards the substrate 7 to orientate and accelerate thereto semiconductor ions, thus promoting the deposition of the semiconductor material on the substrate 7.
The embodiment illustrated by FIG. 2 is similar to the embodiment illustrated by FIG. 1 except in that the mixture gas plasma in the semiconductor depositing region 4 of the reaction chamber 1 is orientated and accelerated by the DC electromagnetic field to orientate and accelerate the semiconductor material ions towards the substrate 7, thereby promoting the deposition thereon of the semiconductor.
Accordingly, the embodiment illustrated by FIG. 2 has the same excellent features as those obtainable with the embodiment illustrated by FIG. 1 and the advantage that the non-single-crystalline semiconductor layer on the substrate 7 can be formed with higher density by the orientation and acceleration of the mixture gas plasma towards the substrate 7 by the DC electric field. In this case, however, the DC electric field must be selected to a suitable intensity, for example, 100 to 1000 V in terms of the voltage available from the DC power source 32.
Next, a description will be given, with reference to FIG. 3, of still another embodiment, in which a P type non-single-crystalline semiconductor layer, an I type (intrinsic) non-single-crystalline semiconductor layer and an N type non-single-crystalline semiconductor layer are sequentially formed on each substrate in this order. In FIG. 3, parts corresponding to those in FIG. 1 are marked with the same reference numerals and no detailed descripiton will be repeated. In the apparatus of FIG. 3, four reaction chamber 1, each identical in construction with the reaction chamber 1 described previously in conjunction with FIG. 1, are formed as a unitary structure with one another in such a manner that the semiconductor depositing regions 4 of adjacent ones of the reaction chamber 1 intercommunicate, with a shutter 41 interposed therebetween and the reaction chambers respectively form reaction parts I, II, III and IV.
In this case, the gas sources for the reaction part I do not include the N type impurity compound gas source 18 in the embodiment of FIG. 1; the gas sourbes for.the reaction part II do not include the N type impurity compound gas source 18 and the P type impurity compound gas source 19 in the embodiment of FIG. 1; and the gas sources for the reaction part III do not include the P type impurity compound gas source in the embodiment of FIG. 1. The gas source for the reaction part IV is only the carrier gas source 21 from which is available a carrier gas E' consisting of one or more of helium, neon and hydrogen gases. Each mixture gas supply pipe 11 has a control valve 50 on the side of the reaction part. The reaction part I communicates, on the opposite side from the reaction part II, with a chamber 42, with a shutter 43 interposed therebetween. The chamber 42 is provided for inserting into the semiconductor depositing region 4 of the reaction part I the boat 8 having planted thereon the substrates 7 to be deposited with non-single-crystalline semiconductor layers. The reaction part IV communicates, on the opposite side from the reaction part III, with a chamber 44, with a shutter 45 interposed therebetween. The chamber 44 is provided for taking out from the semiconductor depositing region 4 the boat 8 having planted thereon the substrates 7 deposited with the noncrystalline semiconductor layers. The chambers 42 and 44 have connected thereto respectively via control valves 46 and 47 exhausters 48 and 49 similar to the aforesaid one 24.
The boat 8 having planted thereon the substrates 7, which is placed beforehand in the chamber 42 evacuated by the exhauster 24, is inserted into the semiconductor depositing region 4 of the reaction part I, opening the shutter 43. The insertion of the boat 8 is carried out in such a state in which the reaction part I is entirely evacuated or only the carrier gas E flows into the reaction part I. Then, in the semiconductor depositing region 4 a P type, non-single crystalline semiconductor layer is deposited on each substrate 7 in the same manner as described previously with regard to FIG. 1.
Thereafter, the boat 8 carrying the substrates 7 respectively deposited with the P type, non-single-crystalline semiconductor layers is inserted into the semiconductor depositing region 4 of the reaction part II, with the shutter 41 opened. This insertion of the boat 8 is carried out in such a state in which the reaction parts I and II are entirely evacuated or only the carrier gas E flows therein. In the semiconductor depositing region 4 an I type non-single-crystalline semiconductor layer is formed on the P type, non-single-crystalline semiconductor layer of each substrate 7 in the same manner as described previously in respect of FIG. 1.
Following this, the boat 8 carrying the substrates 7, each having formed thereon the P type, non-single-crystalline semiconductor layer and the I-type, non-single-crystalline semiconductor layer in this order, is inserted from the reaction part II into the semiconductor depositing region 4 of the reaction part III, with the shutter 41 opened. Also in this case, the boat 8 is inserted into the reaction part III in such a state in which the reaction parts II and III are entirely evacuated or only the carrier gas E flows therein. In the semiconductor depositing region 4 of the reaction part III an N type, non-single-crystalline semiconductor layer is deposited on the I type, non-single-crystalline semiconductor layer of each substrate 7 in the same manner as described previously with reference to FIG. 1.
Then, the boat 8 which carries the substrates 7, each having formed thereon the P type, I type and N type, non-single-crystalline semiconductor layers in this order, is inserted from the reaction part III into the semiconductor depositing region 4 of the reaction part IV, with the shutter 41 opened. In this case, the boat 8 is inserted into the reaction part IV in such a state in which the reaction parts III and IV are entirely evacuated or only the carrier gases E' are passed thereinto. In the semiconductor depositing region 4 of the reaction part IV the P, I and N type, non-single-crystalline semiconductor layers formed on each substrate 7 are annealed by a carrier gas plasma into which the carrier gas E' is ionized in the gas ionizing region 3.
Thereafter, the boat 8 carrying the substrates, each deposited with the P, I and N type, non-single-crystalline layers, is inserted into the chamber 44 from the reaction part IV, with the shutter 45 opened. In this case, the reaction part IV is entirely evacuated or only the carrier gas E' is passed thereinto.
Then, the substrates having thus deposited thereon the P, I and N type, non-single-crystalline semiconductor layers are taken out from the chamber 44.
It will be apparent that many modifications and variations may be effected without departing from the scope of the novel concepts of this invention. | A multi-layer semiconductor manufacturing method which employs a plurality of sequentially arranged, adjacent reaction chambers and a plurality of normally closed shutter means respectively separating the reaction chambers. The reaction chambers are each provided with a gas inlet and gas outlet where the reaction chambers each have positioned therein a substrate. The method includes (a) respectively depositing semiconductor layers on the substrates by respectively introducing semiconductor compound gases into the reaction chambers through the gas inlets thereof in such a state that the gases in the reaction chambers are exhausted therefrom through the gas outlets thereof and by respectively applying ionizing electromagnetic fields to the semiconductor compound gases to ionize them into semiconductor compound gas plasmas while at the same time respectively passing semiconductor gas plasmas into the reaction chambers by discharging therefrom the gases, (b) displacing the shutter means and respectively moving the substrates to the next adjacent reaction chambers while removing the substrate in the last chamber, which may be a taking out chamber, while at the same time evacuating entirely the first chamber which may be an insertion chamber, and the remaining reaction chambers or passing therethrough only carrier gases and then closing the shutter means, and (c) positioning a substrate in the first or insertion chamber while at the same time taking out substrate from the last or taking-out chamber to thereby fabricate the multi-layer semiconductor having a plurality of sequentially laminated semiconductor layers. | 8 |
FIELD OF THE INVENTION
[0001] The invention relates to drywall construction. More specifically, the invention relates to a device for applying drywall mud or joint compound to corner beads or tape-on-trims prior to their attachment to joints or corners between adjacent drywall panels.
BACKGROUND OF THE INVENTION
[0002] Corner beads are elongate, narrow strips of metal, plastic, or metal with a paper face on one side, or the like, folded or angled along their longitudinal center line, or along a line offset from the center line in some cases, to produce a generally v-shaped cross-section. They are made in various angles and corner shapes, including sharp 90 degree angle corners, sharp corners at other angles, rounded or so-called “bullnose” corners of various angles, and offset or L-shaped corners. Corner beads are also designed for covering both inside (concave) and outside (convex) corners. For application to an inside corner, drywall mud is applied to the outside (convex) faces of an inside corner bead. For application to an outside corner, drywall mud is applied to the inside (concave) faces of an outside corner bead. Joint compound is applied to the appropriate faces of the bead, and the bead is then pressed against the corner, with the joint compound forming an adhesive joint between the bead and corner.
[0003] Although drywall mud or joint compound may be applied to corner beads by hand, this is a time consuming and inconvenient process. Hopper devices have been proposed in the past for applying joint compound to the inside faces of an outside corner bead. One such apparatus is described in U.S. Pat. No. 5,169,449 of Raught. The apparatus comprises a hopper with a V-shaped trough in its base, and triangular shaped end walls at opposite ends of the trough forming a generally V-shaped gap between the lower edge of each end wall and the trough. Removable end panels are adjustably secured to the end panels to adjust the height of the gap. A corner bead is fed through the base of the hopper from one end wall opening to the opposite end wall opening, and drywall mud in the hopper will be applied to the upwardly facing surfaces of the corner bead. All except a thin layer will be scraped off by the edge of the end panel as the corner bead exits the hopper. Removable liners may be placed into the hopper to define different trough cross-sectional shapes, corresponding to different shapes of corner bead, and associated with end panels with corresponding edge shapes.
[0004] Other systems have been designed which allow joint compound to be applied to either the inside or outside faces of the corner for applying the corner bead to inside or outside corners. For example, U.S. Pat. No. 6,907,908 discloses a hopper apparatus for applying joint compound to corner beads that has a hopper for holding a quantity of joint compound and a feeder apparatus secured across the lower end of the hopper. The feeder apparatus has a channel and a series of elongate feeder inserts for selectively securing in the channel. A first set of outside feeder inserts each have a generally V-shaped indented groove extending along their length for guiding an outside corner bead through the feeder apparatus, while a second set of inside feeder inserts each have a generally V-shaped ridge extending along their length for guiding an inside corner bead through the feeder. The feeder inserts in each set have grooves and ridges of different angles and corner shapes matching those of a plurality of different inside and outside corner beads and are releasably secured in the channel.
[0005] One problem with prior art hoppers having corner bead feeders for applying joint compound is that they are used with hoppers that must be filled and then emptied with every use or the drywall compound within the hopper will become too dry to work with. This represents lost time and tedious work to a drywall finishing professional. Moreover, prior art devices for applying drywall compound to a corner bead use panels which scrape the excess drywall compound from the corner bead to obtain the desired surface for coating. However, in the past it has been thought that thin panels were most advantageous, perhaps due to the abrasiveness of drywall compound. However, thin panels allow drywall to escape as the hopper sits, particularly when the hopper is full of compound, and if corner bead is pulled through on an angle, the thin panels will deflect to wipe of excessive amounts of compound.
SUMMARY OF THE INVENTION
[0006] The present invention comprises a device for applying drywall compound to a length of corner bead. The device comprises a trough for holding a quantity of drywall compound and an opening at the bottom of the trough through which a length of corner bead may be inserted. A removable block is located near an opening in the trough having a plurality of grooves located therein for preventing excess drywall compound from adhering to the bead while allowing sufficient compound to remain with the bead. A flange attached to the top of the trough is adapted to be attached to a bucket, the bucket having a portion of the bottom removed, to provide drywall compound to the trough.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 is a top view of an apparatus according to a preferred embodiment of the invention;
[0008] FIG. 2 is a bottom view of an apparatus according to a preferred embodiment of the invention;
[0009] FIG. 3 is front view of an apparatus according to a preferred embodiment of the invention with its legs in a first, extended position;
[0010] FIG. 4 is a front view of an apparatus according to a preferred embodiment of the invention with its legs in a second, retracted position;
[0011] FIG. 5 is a front view of a side plate of a leg of the apparatus according to a preferred embodiment of the invention;
[0012] FIG. 6 is a right side view of an apparatus with a block removed according to a preferred embodiment of the invention with its legs in a first, extended position;
[0013] FIG. 7 is a right side view of an apparatus with a block inserted according to a preferred embodiment of the invention with its legs in a first, extended position;
[0014] FIG. 8A is a front view of a block according to a preferred embodiment of the invention;
[0015] FIG. 8B is a side view of a block according to a preferred embodiment of the invention;
[0016] FIG. 9 is a front view of a pin according to a preferred embodiment of the invention;
[0017] FIG. 10 is a view of a container with the apparatus according to the preferred embodiment of the present invention applied thereto resting upon a second container;
[0018] FIG. 11 is a view of a container with the apparatus according to the preferred embodiment of the present invention applied thereto placed within the second container;
[0019] FIG. 12 is a perspective view of a bottom block according to a preferred embodiment of the invention;
[0020] FIG. 13 is a top view of the device with a bottom block inserted therein according to a preferred embodiment of the invention;
[0021] FIG. 14 is a front view of a block according to another embodiment of the invention;
[0022] FIG. 15 is a front view of a block according to another embodiment of the invention;
[0023] FIG. 16 is a perspective view of a block of FIG. 15 ;
[0024] FIG. 17 is a perspective view of a block of FIG. 16 ; and
[0025] FIG. 18 is a side view of a block and a bottom block according to an embodiment of the present invention adapted for bullnose corner beads.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0026] While this invention is susceptible of embodiment in many different forms, there is shown in the drawings and will herein be described in detail preferred embodiments of the invention with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention and is not intended to limit the broad aspect of the invention to the embodiments illustrated.
[0027] Referring to FIG. 1 , the present invention comprises an apparatus 10 for applying drywall compound to a length of corner molding. The apparatus 10 includes a top plate 12 comprising a circular plate defining a central opening 14 . The top plate 12 has a top surface 18 and includes a plurality of bores 16 generally evenly spaced about the circumference of the top plate 12 .
[0028] As shown in FIG. 2 , attached to a bottom surface 20 of the top plate 12 are two pairs of flanges 22 and 24 . The pairs of flanges 22 and 24 , which may also be provided as a single assembly, are preferably attached by welding an extension 25 of the flange 22 or 24 to the top plate 12 . The flanges 22 and 24 each define through-bores (not shown) through which fasteners 26 are inserted. The fasteners 26 also extend through through-bores (not shown) located in a pair of rotatably attached legs 28 and 30 .
[0029] The legs 28 and 30 each comprise a pair of side plates 32 attached to one another with a pair of bars 34 . The side plates 32 have a profile as shown in FIG. 5 , which includes a bucket rest cutout 33 . Adjacent the bucket rest cutout 33 is a safety hook portion 37 which keeps the side plates 32 in association with the buckets, as described below. The legs 28 and 30 are rotatable about the fasteners 26 between a first, extended position as shown in FIG. 3 where the legs 28 and 30 rest against stops 35 on the flanges 22 and 24 and a second, retracted position as shown in FIG. 4 where the legs 28 and 30 contact one another.
[0030] A V-shaped trough 36 is also attached to the bottom side 20 of the top plate 12 . The trough 36 covers the central opening 14 . Ends of the trough 36 are open as viewed in FIG. 6 , but the end openings are partially covered by end plates 38 extending from the top plate that are located inboard of an outer edge of the trough 36 . A cutout 39 is located in each end plate 38 .
[0031] Placed in the ends of the trough 36 are blocks 40 ( FIGS. 8A and 8B ). Referring to FIGS. 6 and 7 , the blocks 40 fit within the end openings and against the end plates 38 . The blocks 40 generally conform to the end openings of the trough 36 also include a recessed portion 39 that forms a gap 42 near a bottom 44 of the trough 36 . Referring back to FIGS. 8A and 8B , grooves 46 are formed in the bottom of the blocks 40 ( FIG. 8A ). The blocks 40 are preferably made from a phenolic material which is rigid and can withstand the abrasiveness of drywall compound. The gap 42 between the block 40 and the trough 36 is preferably about ¼″ or 3/16″ and the grooves 46 are preferably ⅛″ deep. Additionally, the block 40 is preferably about 1½″ thick. It has been discovered that a thicker block 40 prevents drywall compound from being easily forced through the gap 42 when the apparatus 10 is not being used. The blocks 40 preferably removably held in place by pins 48 ( FIG. 9 ) that extend through the trough 36 and through a bore 100 in the block in the block 40 . A block 40 not defining grooves 46 may also be used on one side of the trough 36 . The block 40 is further located ¼″ or more from the edge of the trough in order to provide a surface of the trough 36 upon which to rest the corner bead or make alignment and insertion of the corner bead easier into the gap 42 easier. Moreover, the block 40 defines a second bore 102 in the block 40 which is located at a different vertical height to provide for a different width gap.
[0032] Finally, it is preferred that corner bead support flanges 44 are attached to either side of the trough with the pin 48 . The corner bead support blocks 44 help support corner bead as it is fed through the apparatus.
[0033] Referring to FIGS. 11 and 12 , the apparatus 10 of the present invention is used by taking a common five-gallon bucket 104 in which drywall compound is normally delivered and cutting a hole in the bottom of the bucket that at least conforms to the size of the opening 14 . The top plate 12 is then attached to the bottom of the bucket 104 of drywall with fasteners, as shown in FIG. 10 . In this manner a common five-gallon drywall bucket is used as a hopper for the apparatus 10 , containing drywall compound which by the force of gravity falls into the trough 36 . The common five gallon bucket 104 further includes a lid which can be replaced on the bucket 104 between uses so that that hopper of the apparatus does not need to be emptied and cleaned between uses.
[0034] The apparatus 10 is used by inserting a length of drywall corner bead into one end of the trough 36 and pushing it through the trough 36 until it extends out the other end of the trough 36 . The drywall compound within the trough 36 adheres to top surface of the corner bead, and the corner bead is pulled through the trough 36 until its full length has gone through the trough 36 . On the exit end of the trough 36 , the gap 40 formed by the recess 39 allows an appropriate amount of drywall compound to exit the trough 36 adhered to the corner bead. The grooves 46 further allow raised beads of drywall compound to exit the trough 36 on the corner bead. In this manner drywall compound is applied to the surface of the corner bead.
[0035] Referring to FIG. 11 , in order to bring the apparatus 10 up to an appropriate working height, the legs 28 and 30 are placed in the position shown in FIG. 3 and placed on top of a second, preferably empty five gallon bucket 106 of the type in which drywall compound is normally delivered. The second bucket 106 further acts as a receptacle to drywall compound that falls off of the corner bead as it is pulled through in order to minimize mess.
[0036] Moreover, the second empty bucket 106 is utilized as a storage receptacle for the apparatus 10 . By placing the legs 28 and 30 in the position of FIG. 4 , the first bucket 104 serving as the hopper and the apparatus can be set into the second bucket 106 as shown in FIG. 12 . In this manner, the first bucket 104 can be sealed with its lid and the apparatus placed into the second bucket 106 and the apparatus does not have to be emptied of drywall compound and cleaned for storage between uses because drywall compound portions of the apparatus 10 will be sealed from air and therefore the drywall compound within first bucket 104 and the trough 36 will not dry out.
[0037] While present invention is described with the trough having the profile of an inverted triangle as shown in FIGS. 6 and 7 , it is within the skill of one of ordinary skill in the art that the drywall trough and the block can take on any appropriate form for different type of corner bead and for applying drywall compound to an opposite side of the corner bead for applying, for example, compound to inside corners, bull nose corners, ells and end caps.
[0038] The preferred embodiment of the present invention also comprises a bottom block 50 as shown in FIG. 13 . The bottom block 50 is placed in the bottom of the trough 36 and, as shown in FIG. 14 , causing the bottom of the tough 36 to be convex rather than concave. Extensions 51 cooperate with the trough to hold the bottom block 50 in place.
[0039] Referring to FIGS. 15-18 , the blocks 40 are replaced with block 52 and block 54 . The block 54 defines a plurality of grooves 56 in a concave portion of the block 54 . The blocks 52 and 54 may optionally also comprise a tapered portion 58 for guiding the corner bead through the device. By using the bottom block 50 and the blocks 52 and 54 , drywall compound may be applied to the other surface of the corner bead so that the corner bead can be applied to inside rather than outside corners.
[0040] Referring to FIG. 19 , the blocks 40 are replaced with blocks 60 , which are modified to have a convex curved bottom surface 62 to handle outside bullnose corner beads. The bottom block 50 is similarly replaced with bottom block 64 which has a concave curved surface 66 that corresponds to the convex surface 62 . Similarly, it will be understood by one of ordinary skill in the art that the block 40 and bottom block 50 can have the appropriate profile to handle corner bead of most any profile used as inside or outside corner beads.
[0041] While the specific embodiments have been illustrated and described, numerous modifications come to mind without significantly departing from the spirit of the invention, and the scope of protection is only limited by the scope of the accompanying claims. | A device for applying drywall compound to a length of corner bead. The device comprises a trough for holding a quantity of drywall compound and an opening at the bottom of the trough through which a length of corner bead may be inserted. A removable block is located near an opening in the trough having a plurality of grooves located therein for preventing excess drywall compound from adhering to the bead while allowing sufficient compound to remain with the bead. A flange attached to the top of the trough is adapted to be attached to a bucket, the bucket having a portion of the bottom removed, to provide drywall compound to the trough. | 4 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to a thin sheet of tabbed tracing paper, vellum, tissue paper or similar material inserted in a book to allow a user to highlight, mark or annotate a passage in the book without having to mark the actual page.
[0002] While reading or researching a book or other type of document, it is often desirable to make notes or highlight particular passages throughout the book or document and to be able to flip between the different annotated pages. For example, a student may find it helpful to make notes in the margins of a textbook or highlight particular paragraphs. It would be highly preferable if this could be done without permanently marking or damaging the pages. For instance, the prices of college textbooks have created a market for used textbooks and a less marked-up textbook would have a higher resale value. The present invention permits a user to annotate a textbook without negatively affecting its physical condition. The annotating can occur in the context of a real-time lecture in addition to other contexts such as regular reading or study sessions.
[0003] It is sometimes also desirable for multiple persons to review and annotate multiple pages in a large document, such as a group review of a report or a group Bible study, without physically damaging the source document. Preferably, there should be a quick and easy way to annotate multiple pages in the document, index the notes, and flip to between the multiple inserts.
[0004] Transparent overlay devices have been known for some time in the art, for example U.S. Pat. Nos. 1,450,261; 1,510,110; 2,791,040; 3,324,823; 5,029,899 and 5,388,861. These prior art devices typically consist of a transparent overlay permanently or semi-permanently attached to the cover or bindings of the book or document. For example, U.S. Pat. No. 2,791,040 discloses a single sheet of transparent acetate placed over a map to allow a navigator to chart a course without marking the map. The acetate sheet is part of an erasable pocket on the exterior of a map folio holding the map or drawing. Similarly, U.S. Pat. No. 1,510,110 teaches a hinged transparent sheet attached to a map guide, and U.S. Pat. No. 1,450,261 discloses a book with tracing paper attached to the outer edge of the book cover which folds over the pages of text. These transparent overlays are limited in that they are part of bulky covers or document holders and are only used with the books or maps placed within the holder or cover. These devices are not convenient to use if a reader wants to annotate multiple books or documents, or multiple pages within the same book or document while retaining the previous notes.
[0005] U.S. Pat. No. 4,970,984 discloses memo marking tabs which can be easily inserted into a document. These marking tabs, however, are made from heavy gauge paper making them non-transparent. While non-transparent inserts still allow for notes to be placed in the document, they cover the printed information on the page. Additionally, inserts made from heavy gauge paper significantly increasing the thickness of the document if multiple tabs are used.
[0006] What is needed is a device for easily annotating or highlighting one or more pages of printed material without leaving permanent marks while still allowing the printed material to be seen and read. It is also desirable for the notes or highlights to be easily removable, reattached or stored for future reference.
SUMMARY OF THE INVENTION
[0007] The present invention provides an insert for placing over a page of a book or other document so as to allow annotation of the page. The inserts are thin enough so as to allow a large number of inserts to be placed within a document without significantly increasing the document thickness or distorting the shape and size of the document when closed. The inserts of the present invention comprise a sheet of transparent or substantially transparent material, and one or more tabs that extend from the outer edges of the sheet to allow a user to index and quickly find a particular insert and the corresponding document page. The sheet has a front face and rear face where the front face is receptive to pencil and ink marks. Optionally, at least one portion of the rear face of the sheet has an adhesive allowing the insert to be affixed to the page.
[0008] The inserts of the present invention can be used with books and documents of almost any type. For example, business documents such as draft press releases, FDA submissions, or regulatory SEC filings that need to be reviewed by multiple personnel represent possibilities for employing articles and methods of the invention. Another general application of the present invention is in the context of a small study group where there is a common practice of sharing a single source document or study guide by each of the group members.
[0009] The present invention also provides a method of annotating a page of a document (such as book, study guide, report, etc.) comprising the steps of a) providing an insert which comprises a thin sheet of transparent or substantially transparent material having a front face and a rear face, and one or more tabs extending from the sides of the sheet, where the front face is receptive to pencil and ink marks, and at least one portion of the rear face contains an adhesive; b) positioning the insert relative to a desired document page so that the adhesive contacts the document page; and c) annotating the insert. In a further embodiment, the adhesive allows temporary fixation to the document page and allows the sheet to be removed without ripping or tearing the page. In a further embodiment, the removed annotated sheet is later reattached to the same document page or to a different document page and annotated further. In another embodiment, multiple inserts are positioned onto multiple different pages in the same document and annotated. The tabs extend beyond the edges of the document allowing a user to find and turn to a particular insert.
[0010] An insert of the present invention is preferably thin. The insert sheet should have a small enough thickness to be flexible, at least substantially transparent, and not significantly add to the weight or thickness of the annotated book or document. The insert sheet should have a sufficient thickness so writing on the insert does not cause ripping or tearing. Thickness is typically described for paper in multiple ways. An absolute measurement of thickness of a single sheet of paper is typically made in mils, where 1 mil= 1/1000 inch. Alternatively, thickness can be determined by weight per 500 sheets of a standard size of paper, and by the paper industry standard of grams per square meter (gsm), also called grammage, as set forth by the International Organization for Standardization (ISO). Standard letter size paper (8½ by 11 inches) is often described as 20 pound paper (with 20 pounds being the weight of 500 sheets of uncut 17″×22″ paper, which the paper manufacturer will then cut into 4 letter-sized reams). Therefore, 500 sheets of 20 pound letter sized paper will weigh approximately 5 pounds. Typical letter size paper has a grammage of approximately 80 gsm.
[0011] One embodiment of the present provides inserts comprising a sheet having a thickness of approximately 0.25 to 3 mils, more preferably a thickness of approximately 0.5 to 2.5 mils, even more preferably a thickness of approximately 1 to 1.5 mils.
[0012] Another embodiment of the present invention provides inserts comprising a sheet having between about 10 and about 60 gsm, more preferably between about 10 and about 40 gsm, even more preferably between about 15 and about 30 gsm.
[0013] Another embodiment of the present invention provides inserts where 500 sheets of letter size inserts weigh between approximately 1.25 and 2.5 pounds, more preferably between 1.5 and 1.75 pounds. It should be noted that the thickness values for one embodiment may not completely overlap with another embodiment. For example, an insert sheet having a thickness of approximately 3 mils may have a grammage greater than 60 gsm.
[0014] Particularly for popular conventional paper stocks used in the publishing industry, the thickness of an annotated insert of the present invention can be described relative to the paper stock, i.e., the thickness of the insert is less than or equal to a specified percentage of the thickness of the document page. In one embodiment, the thickness of the insert is no more than about 2% to about 80% of the document sheet thickness, more preferably no more than about 50%.
[0015] The inserts of the present invention have one or more tabs extending from the outer edges of the sheet. The one or more tabs are analogous to the size and shape of tabs that are found on a conventional manila file folders or 3-ring binder dividers. In one embodiment, the insert contains two to six tabs depending on the size of the document to be annotated and the size of the insert. The tabs can be positioned anywhere along the top of the sheet, the bottom of the sheet, the side of the sheet opposite from the binding, or a combination thereof. Preferably, no tabs are positioned at the edge of the sheet that is positioned along the binding of the annotated book or document. The tabs may be made from the same material as the sheet and may form a seamless structure with the sheet. Alternatively, the tabs may be made from a different material and attached, such as by glue, to the rest of the sheet.
[0016] The tab feature allows for indexing the annotations made to the book or document and is particularly useful for finding specific annotations or pages in a book or document containing multiple inserts. In one embodiment, the tabs of different inserts are located at different positions along the top, bottom or side of the sheet so that the tabs of the separate inserts will not overlap each other when multiple inserts are placed in the same book or document. In one embodiment, the tabs are also color coded to assist in differentiating between the tabs. In another embodiment, the tabs are thin enough to allow the tab to be more flexible and bend without ripping or tearing compared to harder or thicker tabs. This can enhance the resiliency and durability of the tab. For example, when the insert is left in a book, the book can be repeatedly shelved while not substantially diminishing the tab integrity.
[0017] The adhesive is optionally present in one or more areas on the surface of the rear face of the sheet. In one embodiment, this area is a strip along the side or top of the sheet. This strip can correspond to the margins of the document page so that the adhesive does not contact the text of the document. Adhesive note pads or sticky notes known in the art have relatively thick strips of adhesives which can cause ripping or tearing of the insert or document page when the insert is removed. Preferably the adhesive is present in small enough amounts that the insert or pages of the document are not ripped when the insert is removed. In one embodiment, the adhesive is present as one or more circular areas or dots on the rear face of the sheet. In a further embodiment, the adhesive dots are spread along the side or top of the sheet starting approximately half of an inch to one inch from one edge of the sheet and continuing to approximately half of an inch to one inch from the opposite edge. This strip of adhesive dots can also be positioned so that it contacts the margin of the document page. The use of adhesive dots provides a sufficient adhesive force across the sheet and allows the insert to be removed from the document page without ripping the document page or the insert. The use of adhesive dots is preferable over a solid adhesive strip because a smaller area of the original document will come into contact with the adhesive thereby reducing the chance that the original document will be pulled up, marked or torn when the adhesive is removed. This is especially beneficial if the sheet is being inserted over a piece of art work (an old text of natural science pictures for instance).
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIG. 1A and FIG. 1B show an insert of the present invention having a tab positioned on the side ( FIG. 1A ) of the sheet or on the top ( FIG. 1B ) of the sheet. FIG. 1C shows an insert having an adhesive strip on the rear face of the sheet. FIG. 1D illustrates the thickness of an insert of the present invention. FIG. 1E shows an insert having a plurality of circular adhesive dots on the rear face of the sheet.
[0019] FIG. 2 shows an insert of the present invention positioned relative to a page in a document.
DETAILED DESCRIPTION
[0020] As used herein, “annotate” and “annotating” broadly refers to writing notes (including but not limited to letters, numbers, symbols and words), drawing, underlining, highlighting, coloring, shading or otherwise marking a writable surface in relation to a printed document. Annotations can be made on the same page of a document of interest; however, it is the objective of the present invention that annotations are made on transparent or substantially transparent inserts placed over the document of interest. Materials suitable for inserts of the present invention include paper of all types, particularly tissue paper and tracing paper, vellum, and similar materials commonly used as writing surfaces that are receptive to pencil and ink marks.
[0021] By “receptive to pencil and ink marks” it is meant that it easy to mark the surface with a ballpoint pen, pencil, highlighter or other common writing utensil. Other protective covers and inserts, such as plastic transparencies, are not easily marked by ballpoint pen or pencil and may require markers adapted for marking that particular material. This makes it inconvenient to annotate the document.
[0022] The inserts of the present invention comprise a sheet that is transparent or at least substantially transparent similar to conventional tracing paper. As used herein, “substantially transparent” should be understood as permitting sufficient passage of light to permit the viewing of an underlying image, particularly the text of a book or other document. The sheet covers at least a portion of the relevant text on the document and is typically rectangular but can be any shape. In the present invention, the sheet is transparent or substantially transparent so that the underlying document can be seen and read while the insert is placed over the document. This allows the notes or highlights to be placed and read in the correct position relative to the original text.
[0023] FIG. 1A and FIG. 1B show an insert 10 of the present invention having a sheet 12 , an interior or binding edge 11 of the sheet 12 , and a projecting tab 14 which can be present on any non-interior edge such as the side ( FIG. 1A ) or the top of the insert ( FIG. 1B ). Typically, the insert 10 will be placed over a document page so that the interior or binding edge 11 is along the side of the page next to the binding. FIG. 1C shows the rear face of an insert 10 having an adhesive section 16 . Preferably when the insert 10 is placed over a document page, the adhesive section 16 is positioned so that it contacts the margin of the page next to the binding. In this embodiment, the adhesive section 16 is a strip that is indented from the edges of the sheet 12 , preferably by at least ½ of an inch from the top and bottom edges and up to ¾ of an inch from the binding edge 11 . FIG. 1D shows an insert 10 having a depth/thickness of dimension 18 . Preferably dimension 18 is comparable to that of conventional tracing paper, vellum, and/or tissue paper. In one embodiment of the present, the insert thickness 18 is approximately 1 to 1.5 mils.
[0024] FIG. 1E shows the rear face of an insert 10 having a plurality of circular adhesive dots 17 instead of an adhesive strip. For an insert that is 7 inches by 9 inches or larger, the adhesive dots 17 need not be more than 2 mm in diameter and are as small as 1 mm in diameter. The adhesive dots are spaced between 1 cm and 3 cm apart from one another and can be arranged in a straight line across the sheet 12 , or can be arranged in other configurations, such as a group of dots at each corner of the sheet 12 . The adhesive dots 17 can be smaller than 1 mm in diameter (as small as 0.5 mm) for smaller sized inserts. The infrequency of the adhesive dots 17 and the minimal size help protect the original document from tearing and are less likely to leave residual adhesive on the document page.
[0025] FIG. 2 shows an insert 10 of the present invention positioned relative to a page in a document 30 . Annotations 20 are provided by a user writing directly on sheet 10 while it is positioned on top of document 30 and can be text or other kind of mark or highlight.
[0026] The adhesive on the rear face of the sheet allows the insert to be temporarily fixed to the document page. The adhesive allows positioning of the insert relative to the document information content. For example, a user can conveniently place text-based lecture notes or study notes on the insert next to the relevant portion of the text.
[0027] The adhesive of the present invention also allows the insert to be removed and re-inserted if necessary. This allows multiple users to annotate a single document. For example, User 1 can annotate a document such as a topical study guide that may accompany a small Bible study group. User 2 can similarly annotate the same document. Thus multiple participants can use a single document. Furthermore, by removing the annotation sheet, the method is conducive to allowing a first participant to annotate while allowing a second participant to independently annotate without having ready access to the annotations of the first participant. This is a desirable advantage that is otherwise generally impeded when a single document is available for annotation. The adhesive aspect of the annotation sheet can conveniently enhance the ability of maintaining the annotations of the first participant proximal to the document. For instance, the annotation sheet of the first participant can be placed inside the back cover of the document.
[0028] The insert can be any size and is preferably substantially the same size as the document of interest (e.g. the page of a book to be annotated). Common page sizes for use with books range from 2½ inches by 3½ inches to 8 by 10½ inches. Additionally, sizes can include larger sizes such as maps and textbooks.
[0029] By “substantially the same size” it is meant that the length and width of the insert, aside from the tabs, is within 10% of the size of the document to be annotated. In one embodiment, the inserts are slightly smaller than the pages of a book so that they can be easily inserted into a book. It may be preferable that the insert be slightly smaller than the page so that the insert can completely fit within the book or document except for the tabs. Preferably, the tabs of the insert will protrude from the pages.
[0030] The reduced thickness allows the insert to have a relatively larger surface area compared to tape flags or smaller Post-it® notes or flags known in the art. The increased surface area provides a larger area to make notes and also enhances the ability to maintain the insert's location in the document. The ability of the insert to remain fixed to the page is affected by a combination of (a) the frictional force between the total surface area of the insert against the annotated page; (b) the frictional force/leverage factor from positioning the annotation sheet towards the binding of the book or document; and (c) the adhesive force from any adhesives on the rear face of the insert. A larger surface area will increase the frictional force between the insert and the page and results in a superior ability of the insert to stay with the document versus the common occurrence where a tape flag or conventional sticky note quickly or eventually falls out of the document. A larger surface area also means that less adhesive is required to keep the insert fixed to the document page.
[0031] Additionally, the reduced thickness allows multiple inserts to be inserted into a book or document while having a minimal effect or no effect on the overall document thickness. This allows for multiple inserts to be used while preserving the document binding structure and reducing potential for damage. This is particularly useful in hardcover bound books. For example, the insert sheet is thin enough so that it is possible to add upwards of 80 insert sheets without negatively affecting an average hard cover book having 280 pages or more. Conventional tape flags or sticky notes can be made to have surface areas as large as the inserts of the present invention, however, the thickness of these conventional inserts would result in significantly increasing the weight or deforming the shape of the book or document if multiple sheets are used.
[0032] The inserts are optionally partially or completely tinted with a color. The inserts can be any color, including but not limited to green, blue, white, cream, yellow, grey, mauve, orange and combinations thereof, as long as the sheet remains at least substantially transparent. The sheet and tabs of the insert may both be tinted or un-tinted independently of each other, and may be tinted different colors. The colors can be used to emphasize particular inserts or match topics to a particular color. Optionally, the inserts may also contain lines across the sheet similar to notebook paper. The lines can be any color, including but not limited to white, black and grey, that is easily discernable and should be thin enough so as not to block the underlying document text. For example, white lines can be used where the sheet is a darker color, or black lines can be used where the sheet is a lighter color. Additionally, the lines can be a darker shade of the sheet color, i.e., the sheet is tinted blue or cream color and has dark blue or dark tan lines.
[0033] While the invention has been described with certain preferred embodiments, it is understood that the preceding description is not intended to limit the scope of the invention. It will be appreciated by one skilled in the art that various equivalents and modifications can be made to the invention shown in the specific embodiments without departing from the spirit and scope of the invention. Every formulation or combination of components described or exemplified herein can be used to practice the invention, unless otherwise stated. Whenever a range is given in the specification, for example, a size range, a thickness range or a composition range, all intermediate ranges and subranges, as well as all individual values included in the ranges given are intended to be included in the disclosure. Moreover, any use of a term in the singular also encompasses plural forms. All publications referred to herein are incorporated herein to the extent not inconsistent herewith. | Transparent or substantially transparent sheets of paper or similar material suitable for inserting into a book or placed over a document are used to highlight or annotate a document without permanently marking or damaging the page. The inserts are thin enough so as to allow several inserts to be placed within a book without significantly increasing the book thickness or distorting the shape and size of the book when closed. Additionally, the inserts contain one or more tabs to allow a user to index and quickly find a particular insert and the corresponding page. An adhesive is present on the rear side of the insert to fix the insert to the page being annotated. | 1 |
FIELD OF THE INVENTION
[0001] 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 area array solder ball interconnections at high temperatures.
BACKGROUND OF THE INVENTION
[0002] 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 of up to 200 C. has several advantages and is becoming increasingly important in the semicoductor industry.
[0003] 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.
[0004] 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.
[0005] 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 pills 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.
[0006] 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.
[0007] 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 dependant 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 temperature and causes a high resistive oxide layer to form on the surface of the probe contact.
OBJECT OF THE INVENTION
[0008] 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.
[0009] 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.
[0010] 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.
[0011] 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.
[0012] Yet another object of the present invention is to provide suitable polymer material for supporting the probe contacts that has coefficient of thermal expansion that is 200 C.
[0013] Yet a further object of the present invention is to provide a probe with cup shaped geometry to contain the high temperature creep of the solder ball interconnection means on the integrated circuit devices during burn-in testing.
[0014] 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
[0015] 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.
[0016] Another broad aspect of the present invention is a method including the steps of: proving a substrate having a surface; bonding an elongated electrical conductor form said ball bond leaving an exposed end of said elongated conductor, and flattening the exposed end.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] 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:
[0018] [0018]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.
[0019] [0019]FIG. 2 shows an enlarged cross section of a single high density integral rigid test probe attached to the fall out wiring on the test substrate.
[0020] FIGS. 3 - 7 show the processes used to fabricate the high density integral rigid test probe structure on a fan out wiring substrate.
[0021] [0021]FIG. 8 shows an alternate embodiment of the high density integral rigid test probe structure with a cup shaped geometry surrounding the probe contact.
[0022] [0022]FIG. 9 shows an alternate embodiment of the high density integral rigid test probe with multiple probe arrays on a single substrate.
[0023] [0023]FIG. 10 shows the structure or FIG. 1 with contact locations on a second surface.
[0024] [0024]FIG. 11 shows the structure of FIG. 6 with conductive pins at the contact locations on the second surface.
[0025] [0025]FIG. 12 schematically show the structure of FIG. 1 in combination with a means for moving the probe into engagement.
DETAILED DESCRIPTION OF THE INVENTION
[0026] [0026]FIG. 1 shows a cross section of a test substrate ( 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 probes ( 12 ) are attached to the first surface ( 11 ) of the substrate ( 10 ). The probes are used to contact the solder balls ( 22 ) are attached to the first surface ( 21 ) of the integrated circuit device ( 20 ).
[0027] [0027]FIG. 2 hows 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 polmer 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.
[0028] [0028]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 ).
[0029] 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 ).
[0030] 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 or 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 or 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 provide 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.
[0031] [0031]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.
[0032] [0032]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.
[0033] 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. Even 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.
[0034] [0034]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 ).
[0035] [0035]FIG. 11 shows the structure of FIG. 6 with elongated conductors ( 74 ) such as pins fixed to the surface ( 76 ) of pad ( 70 ).
[0036] [0036]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.
[0037] While we have described our preferred embodiment 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. Thee 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 |
TECHNICAL FIELD
[0001] The invention is concerned with a method and a mobile telecommunication network for detection of device information of mobile stations used.
BACKGROUND ART
[0002] GSM, together with other technologies, is part of an evolution of wireless mobile telecommunication that includes e.g. General Packet Radio System (GPRS), and Universal Mobile Telecommunications Service (UMTS).
[0003] The Global System for Mobile Communication (GSM) is a standard for digital wireless communications with different services, such as voice telephony. The Subscriber Identity Module (SIM) inside GSM phones was originally designed as a secure way to connect individual subscribers to the network but is nowadays becoming a standardized and secure application platform for GSM and next generation networks.
[0004] UMTS is the next (3 rd ) generation mobile communication system, which provides an enhanced range of multimedia services, such as video. UMTS has specified the use of the USIM (universal SIM) as the evolution of SIM. In GSM and UMTS networks, the (U)SIM card is central both for subscriber identification and for providing value added services to users. Usually referred to as a SIM card, the USIM (Universal Subscriber Identity Module) is the user subscription to the UMTS mobile network. The USIM contains relevant information that enables access onto the subscribed operator's network.
[0005] The functional architecture of a GSM system can be broadly divided into the Mobile Station, the Base Station Subsystem, and the Network Subsystem. The subscriber carries the mobile station, the base station subsystem controls the radio link with the mobile station and the network subsystem performs the switching of calls between the mobile users and other mobile and fixed network users.
[0006] The Mobile Station (MS) is the equipment the GSM user sees from the whole system. It actually consists of two distinct entities. The actual hardware is the Mobile Equipment (ME), also refered to as the “terminal” or the “handset”, which consists of the physical equipment, such as the radio transceiver, display and digital signal processors. The subscriber information is stored in the Subscriber Identity Module (SIM), implemented as a Smart Card.
[0007] The SIM card is a smart card that saves subscriber information about identity, subscription, subscriber environment, radio environment and other information. The information in the SIM is stored in a logical structure of files.
[0008] The mobile equipment is uniquely identified by the International Mobile Equipment Identity (IMEI) being a unique code that corresponds to a specific GSM handset. The SIM card, in turn, is identified by the Integrated Circuit Card Identity (ICCID) determining the serial number of the card, and contains the International Mobile Subscriber Identity (IMSI), identifying the subscriber, a secret key for authentication, and other user information.
[0009] The term “device information” comprises in this text both equipment information, such as the IMEI, and SIM information, such as the ICCID or the subscriber identity, i.e. IMSI. The IMEI and the IMSI are, however, independent and can thereby provide personal mobility.
[0010] The central component of the network subsystem is the mobile services switching center (MSC). This acts like a normal switching node of the PSTN (Public Switched Telephone Network) or ISDN (Integrated Services Digital Network) and connects the mobile signal to these fixed networks. It additionally provides all the functionality needed to handle a mobile subscriber. The Mobile Station Integrated Service Digital Network Number, MSISDN, is the standard international telephone number used to identify a given subscriber.
[0011] The Short Message Service Center (SMSC) enables subscribers to send and receive messages in the Cellular network. It can be interfaced with Mobile Switching centers (MSCs) over an SS7 link. The entities, which may receive or send short messages may be located in a fixed network, a mobile station, or another service center. The Short Message Service Center (SMSC) is responsible for the relaying, storing and forwarding of a short message between such an entity and a mobile station.
[0012] The operator declares the subscription in a database inside the network, which holds the correspondence between the IMSI and the MSISDN. By inserting the SIM card into another GSM station, the user is able to receive and make calls from that terminal, and receive other subscribed services.
[0013] When a new (U)SIM is issued, a lot of information, both personal and to some extent operator defined, is lost, unless this information is copied from the old (U)SIM to the new (U)SIM. This could for example be the phone book.
[0014] Introducing a new terminal has other problems—since it is not personalized as (U)SIM cards are. Hence it is required to be configured with network settings to be enabled to use the different services the Mobile Service Provider offers. Apart from that, the same problem with personal information and services, as with the (U)SIM Cards, applies.
[0015] Today it is not possible to know what handset model a user is using, if not explicitly notified by the user. This is especially a problem when trying to keep a repository up to date with active handsets, potentially to be used for updating the handset with appropriate data.
OBJECT OF THE INVENTION
[0016] The object of the invention is to develop a solution for better management of subscriber and equipment information, especially in situations wherein subscriber information changes.
SUMMARY OF THE INVENTION
[0017] The method of the invention is performed in a mobile telecommunication network for detection of device information including subscriber information and equipment information. The network comprises a mobile station with a terminal part and with a module for subscriber information and an application, and a repository for storing device information. In the method, the application in the mobile station detects device information of a mobile station attaching to the network, compares the detected device information to the device information previously stored in the mobile station, and sends the detected device information to be stored in the network repository if it does not correspond to the information previously stored.
[0018] The mobile telecommunication network of the invention further comprises a detector for handling device information. The mobile station of the invention included in this network has an application and detects device information.
[0019] The preferable embodiments of the invention have the characteristics of the subclaims.
[0020] The invention thus provides terminal based methods for detecting what devices (mobile station, i.e. handset and/or SIM) a mobile user is using, and means for provisioning them with relevant information.
[0021] The invention is especially topical in a situation, wherein the subscriber either has changed his mobile terminal (by inserting the old SIM in the new terminal) or changed the SIM card (by removing the old SIM card from the terminal and inserted a new one). In this text, the term “Terminal Switch” is used for the former case and the term “SIM switch” for the latter case.
[0022] The method of the invention is primarily implemented in the GSM or UMTS network, whereby the subscriber information, such as information about identity, subscription, subscriber environment, radio environment, etc. described by the IMSI, is stored in
[0023] The Subscriber Identity Module (SIM) inside GSM phones and the Universal SIM (USIM) when implemented in the UMTS network.
[0024] The solution of the invention has two major steps, i.e. the detection of a new device (SIM or terminal) being used by a user and updating the new device with relevant data. This solution is based on an application executing on a Smart Card, such as the SIM card. The detection of the new device is sent to a central system (Device Switch Detector, which either can be a Terminal Switch Detector TSD or a SIM Switch Detector (SSD) to act on this information. The solution could for example be implemented as a combination of Wireless Internet Browser applications (WlBlet(s)) and a plug-in, for WIB enabled cards or as a Java Card Applet for Java Cards or as a SIM application toolkit.
[0025] The detection of the device information is performed by sending this information from the mobile subscriber terminal to an application in the mobile station, as a consequence of which the application performs said detection.
[0026] The detection of a new terminal (Terminal Switch) is based on the terminal identity (IMEI) being stored on the SIM Card. When the SIM Card is initialized the IMEI from the previous initialization is compared with the current IMEI, requested by the application from the handset. If they differ—it is an indication of that a terminal switch has taken place and this information is sent to the TSD server for further processing.
[0027] The detection of a new SIM card (SIM Switch) could be detected by using the same mechanism as above (comparing IMEI), or a dedicated mechanism (comparing a dedicated SIM Switch parameter). When the SIM card is initialized, the application reads the IMEI (or the dedicated SIM Switch parameter) from its stored position, which is on the SIM card. If it is found to be 0 (or not defined), it indicates that the SIM is being used for the first time. The unique SIM identity (e.g. ICCID) is sent to the SIM Switch Detector to evaluate the given information and make the decision whether it was a SIM Switch or not. The decision is based on comparing the given SIM identity read from the SIM card with the information previously stored in the SIM repository in the network.
[0028] The advantages of the invention are that automatic provisioning is possible on terminal switch, which solves the problems faced in the background art section. The solution to all the non-configured handsets is to automatically provision them with accurate configuration data when a handset is being used for the first time.
[0029] Moreover, personal settings from an old handset can be restored. When a user has started to use a new handset it could be updated with personal information, in addition to the network configuration data. Personal information that was on the old handset, and stored in the network, could be downloaded to the handset, upon user acknowledgement. Personal information could for example be WAP bookmarks, Java applets, logos, ringtones etc.
[0030] A detection of a handset switch will lead to that the system downloads the personal settings used in the old handset, previously stored in the system. Applications could also be downloaded and the system could even download the same applications potentially upgraded to suit the capabilities of the new handset, e.g. a game designed for a small screen used on the old handset could be replaced with the same game designed for a larger color screen—according to the capability of the new handset.
[0031] When a new SIM has been introduced it could be updated with information from an image of the old SIM card. Operator defined data, if not pre-personalized, could automatically be downloaded. Personal data if stored/backed-up in the operator's domain, e.g. the Phonebook, could be downloaded, preferably after a question been sent to the user (by e.g. Text SM, WIG push, or WAP push) and acknowledged by the same (via e.g. Text SM, WIG message, or WAP message).
[0032] In the following, the invention will be described by means of some embodiments of the invention by referring to figures. The invention is not restricted to the details of the description.
FIGURES
[0033] FIG. 1 shows an environmental view of a network of the invention, wherein an embodiment of the method of the invention can be implemented.
[0034] FIG. 2 presents a flow scheme of an embodiment of the method of the invention implemented in the network of FIG. 1
[0035] FIG. 3 presents a flow scheme of an other embodiment of the method of the invention implemented in the network of FIG. 1
DETAILED DESCRIPTION
[0036] FIG. 1 is an architectural view of the network structure, in which the method of the invention can be implemented. In FIG. 1 , it is assumed that the invention is implemented in the GSM network.
[0037] The GSM network has different parts. The Mobile Station (MS) with reference number 1 is carried by the subscriber. The Base Station Subsystem (BSS) controls the radio link with the Mobile Station. A cell is formed by the coverage area of a Base Transceiver Station (BTS) having reference number 2 in FIG. 1 ; which serves the MS 1 in its coverage area. Several BTS stations together are controlled by one Base Station Controller (BSC) having reference number 3 in the figure. The BTS 2 and BSC 3 together form the Base Station Subsystem (BSS). The Mobile Station and the Base Station Subsystem communicate across the air interface through a radio link.
[0038] The Network Subsystem, the main part of which is the Mobile services Switching Center (MSC) (not shown) performs the switching of calls between the mobile and other fixed or mobile network users, as well as management of mobile services, such as authentication. The Operations and Maintenance center (not shown) oversees the proper operation and setup of the network.
[0039] The communication from BSC 3 further is based on signaling system no. 7 (SS7) protocol, which is indicated with reference number 5 in the figure and constitutes the wireless network signaling infrastructure in GSM. SS7 is a global standard for telecommunications defined by the International Telecommunication Union (ITU) Telecommunication Standardization Sector (ITU-T). The SS7 standard defines the procedures and protocol by which the network elements exchange information over a digital signaling network to effect secure worldwide telecommunications.
[0040] The Short Message Service Center (SMSC) with reference number 4 in FIG. 1 enables subscribers to send and receive messages and is interfaced with the Mobile Switching centers (MSCs) over an SS7 link.
[0041] All the above functions are parts of the GSM standard. When implemented in GSM, the invention introduces some further functions in the network.
[0042] Inventive functions in FIG. 1 is a Device Switch Detector 9 that can be a Terminal Switch Detector (TSD) or a SIM Switch Detector (SSD) depending on which embodiment of the invention it is question about. When the Device Switch Detector 9 is a TSD, a repository 10 that contains lists of pairs of IMEI/IMSI, IMEI/MSISDN or IMEI/IMSI/MSISDN values is connected to it. When the Device Switch Detector 9 is an SSD, a repository 10 that contains lists of pairs of IMSI/MSISDN/ICCID values is connected to it.
[0043] A further inventive function in FIG. 1 is an application 12 on the SIM card executed by a signal from the SIM operating system that the terminal has been switched on.
[0044] In a first embodiment, the application program is a Terminal Switch Application, which asks the telephone of the IMEI and reads the IMEI from a memory space on SIM. All data on the SIM are stored in files and one of those is available for the application. Thereafter, the application 12 evaluates whether there is a new terminal, i.e. if the read IMEI and the previously stored IMEI differ from eachother. If so, this information is sent to a Terminal Switch Detector (TSD) 9 , which interprets the signal by means of a repository 10 containing lists of pairs of IMEI/IMSI values or IMEI/MSISDN values and connected to the TSD 9 .
[0045] When TSD gets the information that a subscriber has changed telephone (the IMEI/IMSI or IMEI/MSISDN pair updated with a new IMEI), TSD then updates the repository information and also the IMEI information in the SIM file by e.g. sending a SMS message to SIM and preferably sending a signal to those components, that are interested in knowing that a subscriber has changed telephone (a terminal switch has taken place). This change is interesting because it is now known that an unconfigured telephone exists and that suitable things can be sent to the telephone to have it work with Global Packet Radio Services (GPRS), Wireless Application Protocol (WAP), e-mail etc.
[0046] In another embodiment of the invention, the application program is a SIM Switch Application, which reads an indicator from a memory space on the SIM in order to evaluate whether there is a new SIM. If so, this information is sent to a SIM Switch Detector (SSD) 9 , which interprets the signal by means of the repository 10 . In this embodiment, the repository contains lists of MSISDN/IMSI/ICCID values and is connected to the SSD 9 . When SSD gets the information that a subscriber has changed SIM, it updates the information in the MSISDN/IMSI/ICCID repository and sends back an acknowledgement to the SIM Switch Application to store a value for the SIM Switch indicator that a SIM Switch has taken place.
[0047] The TSD or SSD is connected to the SMSC 4 in FIG. 1 , which enables it to send and receive information about IMEI/MSISDN/IMSI/ICCID values in form of SMS messages to and from the SIM 11 .
[0048] FIG. 2 presents a flow scheme of an embodiment of the method of the invention used when a mobile station attaches to the network, here a network according to FIG. 1 . It is assumed that the user of the mobile terminal has changed his mobile terminal but kept his old SIM card by transferring it to the new terminal.
[0049] When the terminal is switched on (step 1 of FIG. 2 ), a signal is sent (in step 2 of FIG. 2 ) from the SIM operating system to the Terminal Switch SIM application in order to start said application.
[0050] The application starts with asking, in step 3 of FIG. 2 , the terminal for its International Mobile Equipment Identity (IMEI), i.e. the unique code that corresponds to a specific GSM terminal.
[0051] When the terminal has given the requested IMEI information to the application, the Terminal Switch SIM application compares in step 4 of FIG. 2 the given IMEI information with the IMEI value read from the SIM file showing what terminal the SIM was in the last time it was restarted. If it in step 5 of FIG. 2 is found that the new IMEI differs from the previously stored IMEI, a terminal switch is considered to have happened.
[0052] Information about the subscriber, either the International Mobile Subscriber Identity (IMSI) or the standard International telephone number used to identify a given subscriber (MSISDN) or both as well as the new IMEI is thereafter sent in step 6 of FIG. 2 to the Terminal Switch Detector (TSD) with an SMS message. The TSD then stores the new information in the IMSI/IMEI, IMSI/MSISDN/IMEI or MSISDN/IMEI repository in step 7 of FIG. 2 and sends acknowledgement to the Terminal Switch SIM application to update IMEI information on SIM in step 8 of FIG. 2 .
[0053] FIG. 3 presents a flow scheme of an other embodiment of the method of the invention used when a mobile terminal attaches to a network according to FIG. 1 .
[0054] Now it is assumed that the user of the mobile terminal has changed his SIM card by removing the old SIM card and inserting a new one into the terminal (old or new).
[0055] When the terminal is switched on (step 1 of FIG. 3 ), a signal is sent (in step 2 of FIG. 3 ) from the SIM operating system to the SIM Switch SIM application in order to start said application.
[0056] The application starts with step 3 of FIG. 3 , wherein the SIM Switch Application reads the value of a SIM Switch Indicator. This indicator is a variable on the SIM card being e.g. “ 0 ” or undefined until a SIM Switch is reported, and e.g. “ 1 ” after a SIM Switch has been reported.
[0057] If the SIM Switch Application notes in step 4 of FIG. 3 on the basis of the SIM Switch indicator that a SIM Switch has taken place, it sends new IMSI/MSISDN and ICCID information to the SIM Switch Detector (SSD) in step 5 of FIG. 3 . In step 6 of FIG. 3 , the new information is stored in the IMSI/MSISDN/ICCID repository, whereafter an acknowledgement is sent in step 7 of FIG. 3 to the SIM Switch Application to update the SIM Switch indicator to e.g. “1”.
[0058] When the user again changes to a new SIM card, the SIM Switch indicator on the new SIM card has the value “0”, which is read by the SIM Switch application when the terminal is switched on. The SIM Switch Application then again performs steps 4 - 5 and stores the new indicator value “1” when an aknowledgement has come from the SSD that the new information has been stored in the IMSI/MSISDN/ICCID repository. | The mobile telecommunication network of the invention is used for detection of device information, such as subscriber information and equipment information, The network has a mobile station with subscriber information, a base station subsystem, and a network subsystem. The network of the invention has detecting device information for signals sent from the mobile station, a detector for handling the detected information, and a repository for storing device information. The method detects device information of a mobile station that attaches to the network. The detected device information is compared with the device information stored in the network and stored if it does not correspond to the information previously stored in the network. | 7 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application is a national stage application of international application number PCT/CN2015/083877, filed Jul. 13, 2015, titled “Duplex Reactor System for Removal of Tebuconazole and Method thereof,” which claims the priority benefit of Chinese Patent Application No. 201410484704.0, filed on Sep. 19, 2014, which is hereby incorporated by reference in its entirety.
TECHNICAL FIELD
[0002] Implementations herein relate to systems and methods for removal of tebuconazole, more particularly to systems and methods for removal of tebuconazole in water using a duplex reactor including resins loaded with microorganisms.
BACKGROUND
[0003] Pesticides play an important role in controlling agricultural pests and diseases as well as in increasing crop yields. However, the agricultural industry increasingly depends on pesticides, which contaminate soil and water. For example, merely 0.3% of pesticides work on pests, and the remaining 99.7% of pesticides are left on surfaces of crops and in the natural environment including soil and water. Eventually, these pesticides enter rivers, lakes and groundwater through rainfall and irrigation. This results in potential health hazards to humans and other aquatic organisms. Tebuconazole is an important pesticide and widely used in the world. Tebuconazole effectively controls various agricultural diseases such as rust, powdery mildew, net blotch, root rot, Fusarium head blight and smut associated with crops as well as rust, powdery mildew and scab, and other fungal diseases associated with fruits. Currently, tebuconazole has been registered on 65 kinds of crops in more than 50 countries; therefore, related environmental problems are increasingly urgent. Although tebuconazole concentrations in the environment are not high, potential hazards and risks of tebuconazole to the environment cannot be ignored. Therefore, many scholars have studied treatment of tebuconazole in wastewater, and several methods for removal of tebuconazole have been reported. Generally, these methods can be categorized into three main categories.
[0004] The first category includes a biochemical-based method, which utilizes microorganism organisms to break tebuconazole structures and turn these structures into small molecules that are less toxic and/or susceptible to be degraded. Although the method is economically applicable, the method has the following disadvantages: (1) Anti-water quality fluctuation capability is weak, and the method cannot afford charges from high pollution loads in wastewater; (2) Microbial degradation of tebuconazole (e.g., taking 3-5 days) is slower than that of conventional techniques such as adsorption and chemical oxidation based methods. Although it has been reported of strains capable of screening and degrading tebuconazole (Hongping Wu et al., Tebuconazole pesticide screening degrading bacteria and their degradation of performance, pesticide, February 2013 10). However, Hongping Wu et al. does not identify the type of bacteria for removal of tebuconazole, provides no embodiments using the strains as well as systems implementing the method. Therefore, methods for removal of tebuconazole using bio-degradable techniques have not been reported.
[0005] The second category includes an adsorption-based method, which separates tebuconazole from water without altering its chemical structure. Although the absorption-based method is the most common and more efficient approach in the laboratory or the industry, this method has a serious problem: desorption solutions for resin regeneration. Thus, effective desorption disposals have to be used; otherwise secondary pollution will happen. Currently, research has been focused on the adsorption method implementing activated carbon on adsorption of tebuconazole; however, implementations of resin adsorption techniques to remove tebuconazole from wastewater has not been reported.
[0006] The third category includes a chemical-oxidation-based method, which implements chemical-oxidation processes to remove tebuconazole from water. This method has been patented (e.g., An immobilized microorganism treatment of organic phosphorus pesticide wastewater use, Publication Number: CN103102015A). However, this method requires adding more chemical agents, involves complex operations, and incurs high operating costs. Further, this method is not efficient and economically applicable to remove tebuconazole in a low concentration from wastewater. In addition to adding excessive chemical agents, the method may further deteriorate quality of water and increase toxicity of water.
[0007] To overcome these disadvantages, there is a need for developing systems and methods for efficiently remove tebuconazole in water.
SUMMARY
1. Technical Problems to be Solved
[0008] To solve the problems with existing techniques for removal of tebuconazole in water, implementations herein provide systems and methods for removal of tebuconazole in water using resins loaded with microorganisms. The implementations adopt a new type of adsorption resins loaded with microorganisms as adsorption fillers filled into a duplex reactor. The duplex reactor is able to rapidly adsorb and remove tebuconazole in water, and then degrades tebuconazole adsorbed on the resins to regenerate the resins.
[0009] There are techniques related to wastewater treatments including oxidation, bio-degradation and adsorption based techniques. But these techniques are not suitable for removal tebuconazole removal from water. For example, although these techniques have advantages in pesticide wastewater treatment, they have deficiencies, which are provided below.
[0010] (1) Comparison between the implementations herein and existing techniques based on oxidation processes (e.g., Patent 1: Tebuconazole pesticide wastewater treatment, CN Patent NO. 102923919 A). This technique degrades tebuconazole using processes associated with Fenton oxidation, oxidation using chlorine dioxide, iron and carbon-coagulation integrated oxidation. However, there are some problems with removal of tebuconazole using this technique.
[0011] For example, the process requires pH adjustment, consumes large amounts of acid. Also, large amounts of sludge and sediment are produced during the Fenton oxidation of iron and carbon-coagulating sedimentation process. Such substances are hazardous wastes and require safe disposals, which incur higher costs. This technique is usually used for high concentration wastewater treatment; however, it cannot efficiently remove contaminants (e.g., tebuconazole) in low concentrations from water. Therefore, the technique is not economically applicable. Further, disposal of a large number of chemical wastes severely alter quality of water and fail to make balance and protection of water ecosystems.
[0012] (2) Comparison between the implementations herein and existing techniques based on biodegradable processes (e.g., Patent 2: A use of immobilized microorganism method of governance organophosphorus pesticide wastewater, CN Patent Publication No: CN103102015A). For example, domesticated fungus (e.g., Aspergillus Niger ) was adsorbed onto activated carbon with a diameter of 5-8 mml, and the obtained saturated activated carbon containing Aspergillus Niger was placed into waste water to degrade organophosphorus pesticides. However, there are problems for removal of tebuconazole. Aspergillus Niger can only degrade organophosphorus pesticides and is not able to degrade tebuconazole. Activated carbon has mainly microporous structures, which have small adsorption capacity and low adsorption rates. Also, Aspergillus Niger causes clogged pores due to adhesion and adsorption are hardly performed. The active carbon only functions as a carrier of the bacteria; there are no supporting reactor and processing systems. After placing into water, the active carton may be not separated from the water, having difficulties in practical application.
[0013] (3) Comparison between the implementations herein and existing techniques based on adsorption processes (e.g., Patent 3: A pesticide industrial wastewater treatment, CN Patent Publication No: CN101746930 A). The techniques include aerobic biological treatment of wastewater using continuous adsorption between wastewater containing quinolone parathion and magnetic resins. Further the technique uses a suspended bed up flow reactor as magnetic resins to contact adsorption reactors and allow continuous access to water such as to adsorb and remove contaminants from the water. However, the technique has disadvantages. The magnetic resins remove contaminants through ion exchange; however, tebuconazole in water is not ionized. Thus, tebuconazole cannot be removed by ion exchange processes. Further, after adsorption of pollutants, the magnetic resins have to be regenerated using brine as renewable liquid; therefore, disposal processes of the renewable liquid may produce secondary pollution.
2. Technical Solutions
[0014] The implementations relate to a duplex reactor including multiple layers of resins to remove tebuconazole and to degrading of the tebuconazole adsorbed on the resins using microorganisms loading on the resins such that the resins are regenerated and continuous water inlet and outlet are achieved.
[0015] As compared with existing techniques, the implementations have the following features and/or advantages.
[0016] (1) Using polymer resin absorbent materials as microorganism carriers. These resins not only are loaded with microorganisms, but also are capable of adsorbing tebuconazole in water. Adsorption capacity and adsorption rates are high.
[0017] (2) Loading the resins with microorganisms such as Sphingomonas paucimobilis (e.g., Sphingomonas sp.). The microorganisms have a good degradation capacity of tebuconazole, and absorbed resins may be regenerated without additional desorption solutions. Accordingly, removal of tebuconazole does not change water quality and produces no additional desorption and liquid waste.
[0018] (3) New duplex structure and multilayer adsorption materials of the duplex reactor. The duplex reactor effectively increases contacting time among adsorbent materials, microorganisms, and contaminants to improve an adsorption removal rate and a bio-degradation rate associated with tebuconazole in water.
[0019] (4) Multi-cellular polymer support frame in the duplex reactor. The duplex reactor effective reduces swelling and accumulation of pressure among adsorbent materials to avoid fragmentation and loss of the adsorbent materials, meanwhile to avoid compaction and clogging by reducing a size of monolayer stories of adsorbent materials.
[0020] The implementations relate to a duplex reactor for removal of tebuconazole from water. The duplex reactor includes a reactor shell, a reactor inner shell, an inlet pipe, a water distributor, an outlet pipe, an aeration tube, an aeration head, an exhaust pipes, a gas gathering reflective cone, a honeycomb support frame, resins loaded with microorganisms, a backwash water inlet, a backwash water outlet pipe. In some implementations, the inlet pipe is located at the top of the duplex reactor, which is connected to the reactor shell; the exhaust pipe is in the vicinity of a conical collection hood and connected to the reactor inner shell; the outlet pipe is located in the upper part of the reactor, located in the lower part of the conical collection hood, and connected to the reactor inner shell; the honeycomb support frame is located in the reactor inner shell, which is filled with the resins loaded with microorganisms; the water distributor is located at the bottom of the reactor inner shell; the backwash water outlet pipe is above in each layer of the honeycomb support frame and connected to the reactor inner shell; the backwash water inlet pipe is located at the bottom of the water distributor and is connected to the reactor shell; the aeration tube is connected to the aeration head, and the aeration head is located directly above the reactor water distributor.
[0021] Implementations herein relate to systems and methods for removal of tebuconazole in water using resins loaded with microorganisms. The system includes the duplex reactor, a complementary nutrient solution reserve tank, an inlet water sample adjustment tank, a backwash effluent collection tank, a backwash water reserve tank, a filter, a flow meter, a pump and an aeration pump, wherein the complementary nutrient solution reserve tank and the inlet adjustment tank are connected, the duplex reactor is connected to the inlet water sample adjustment tank, the backwash water reserve tank, the backwash effluent collection tank, and the aeration pump.
[0022] Implementations herein relate to a method for removal of tebuconazole in water using resins loaded with microorganisms using the duplex reactor.
[0023] Step 1. Providing the resins loaded with microorganisms:
[0024] (a) Culturing microorganisms by: inoculating Sphingomonas bacterium colonies from plates ( Sphingomonas sp. was isolated from soil. In 1990, Japanese scholars Yabuuchi first proposed Sphingomonas paucimobilis . Takeuchi et al. made changes in 1993. According to 16S rRNA sequence comparison, Sphingomonas paucimobilis belongs to 4 subclass of proteobacteria. The strain of the genus is Gram-negative bacteria, has no spores, shows unilateral born polar flagellar motility, is mostly yellow, is obligate aerobic and produces catalase) into culture media including beef peptone and keeping the culture media from light at temperature 28 degrees Celsius;
[0025] (b) Collecting microorganisms: separating the Sphingomonas paucimobilis at a logarithmic growth phase from the culture media by centrifugation for 20 min with a speed of 5000 G. Washing the Sphingomonas bacteria using a solution (pH=7.3) containing disodium hydrogen phosphate and potassium dihydrogen phosphate;
[0026] (c) Loading the microorganisms to the resins: placing the collected Sphingomonas paucimobilis into culture media containing minerals, adding the resins to the culture media containing minerals, and shaking the culture media containing minerals for 3-5 days to obtain the resins loaded with Sphingomonas paucimobilis ; and
[0027] (d) Filling in the resins: washing the resins loaded with microorganisms using deionized water, and filling the resins into the double honeycomb support frame of the duplex reactor. The used strains are Sphingomonas paucimobilis ( Sphingomonas sp.), and the resins are adsorption resins with a polystyrene backbone or a polyacrylate backbone.
[0028] Step 2. Adding water: adjusting water flow and flow of the complementary nutrient solution, controlling the inlet water sample adjustment tank such that CODCr of water samples is not less than 20 mg/L, allowing the water samples into the inlet pipe of the duplex reactor, and opening the aeration pump. the complementary nutrient solution may include methanol, ethanol, glucose, or a solution of sodium acetate.
[0029] Step 3. Adsorption and bio-degradation of tebuconazole: allowing the water samples pass through multiple layers of the resins, removing tebuconazole by the resin, and discharging adsorption water from the outlet pipe, wherein, at the same time, microorganisms attached to the resins use complementary nutrients, and tebuconazole are used as a carbon source such as to degrade the tebuconazole, and the water samples are kept in the duplex reactor for at least 30 minutes.
[0030] Step 4. Backwash: 7-10 days after the bio-degradation, due to the situation that attached microorganisms metabolism on the resins result in death and loss of certain microorganisms, closing the feed line pumps, valves and outlet valves, opening valves of the backwash water inlet and the backwash water outlet pipe, backwashing the resins for not less than two minutes, placing the backwash water into the backwash water effluent collection tank, discharging the backwash water into a sewage treatment plant, closing the valves of the backwash water inlet pipe and backwash water inlet outlet pipe, opening the valve and the pump of the inlet water pipeline, the water inlet valve, and continuing to run operations.
3. Beneficial Effects
[0031] (1) The duplex reactor is capable of water collection, water distribution, aeration, exhaust, adsorption, bio-degradation, backwash and other functions and therefore is capable of continuously running. The duplex further has a small size but high efficiency for removal of tebuconazole.
[0032] (2) Multi-layer honeycomb support frame and filtering screens can reduce pressure caused by excessive accumulation of resin layers and avoid a situation that the resin layers in water swell and cause enormous pressure and crushing loss. The structure further avoids increase of water resistance caused by hardening of whole resin layers. This reduces head loss and saves power consumption.
[0033] (3) Sphingomonas paucimobilis ( Sphingomonas sp.) loaded on the resins effectively adsorbs tebuconazole. And the adsorption capacity and adsorption rate are high, and removal of tebuconazole takes place without changing water quality.
[0034] (4) Adsorbed resins do not have to be transferred. There is no need of regeneration using decorbent solutions. Sphingomonas paucimobilis ( Sphingomonas sp.) loaded on the resins degrades tebuconazole that are absorbed by the resins to achieve resin regeneration without incurring desorption solutions.
BRIEF DESCRIPTION OF THE DRAWINGS
[0035] FIG. 1 is a schematic diagram illustrating a duplex reactor in accordance with the implementations of the present disclosure. As illustrated, 1 refers to a reactor shell; 2 refers to a reactor inner shell; 3 refers to an outlet pipe of the reactor; 4 refers to a backwash water outlet pipe; 5 refers to an aeration head; 6 refers to a water distributor; 7 refers to an inlet pipe; 8 refers to an exhaust pipe; 9 refers to a gas gathering reflective cone; 10 refers to a honeycomb support frame; 11 refers to a resins loaded with microorganisms; 12 refers to an aeration tube; and 13 refers to a backwash water inlet pipe.
[0036] FIG. 2 is a schematic diagram illustrate a honeycomb support frame (support frame, internal filtering screens) of a duplex reactor in accordance with the implementations of the present disclosure, the left part of the diagram indicates a wall of the support frame, the right part of the diagram shows the support frame and the top portion of the bottom of the filtering screen, which prevents the resins to be washed away.
[0037] FIG. 3 is a schematic diagram illustrating a system structure in accordance with the implementations of the present disclosure. As illustrated, 14 refers to a complementary nutrient solution reserve tank; 15 refers to a regulate water tank; 16 refers to a backwash water effluent collection tank; 17 refers to a duplex reactor; 18 refers to a backwash water storage tank; 19 refers to a filter; 20 refers to a flow meter; 21 refers to a pump; and 22 refers to an aeration pump.
[0038] FIG. 4 is a flow chart illustrating a process in accordance with the implementations of the present disclosure.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0039] The present disclosure is further explained below by examples.
Example 1
[0040] An architecture of a system for processing wastewater is shown in FIG. 3 , and the architecture includes: a duplex reactor ( 17 ), a complementary nutrient solution reserve tank ( 14 ), an inlet water sample adjustment tank ( 15 ), a backwash effluent collection tank ( 16 ), a backwash water reserve tank ( 18 ), a filter ( 19 ), a flow meter ( 20 ), a pump ( 21 ) and an aeration pump ( 22 ), wherein the complementary nutrient solution reserve tank ( 14 ) and the inlet adjustment tank ( 15 ) are connected, the duplex reactor ( 17 ) is connected to the inlet water sample adjustment tank ( 15 ), the backwash water reserve tank ( 18 ), the backwash effluent collection tank ( 16 ), and the aeration pump ( 22 ); the duplex reactor ( 17 ) is connected to the inlet water sample adjustment tank ( 15 ), between which there are the backwash water reserve tank ( 18 ), the backwash effluent collection tank ( 16 ), and the aeration pump ( 22 ).
[0041] As illustrated in FIG. 1 , the duplex reactor ( 17 ) include includes: a reactor shell ( 1 ), a reactor inner shell ( 2 ), an inlet pipe ( 7 ), a water distributor ( 6 ), an outlet pipe ( 3 ), an aeration tube ( 12 ), an aeration head ( 5 ), an exhaust pipe ( 8 ), a gas gathering reflective cone ( 9 ), a honeycomb support frame ( 10 ), resins loaded with microorganisms ( 11 ), a backwash water inlet pipe ( 13 ), a backwash water outlet pipe ( 4 ); wherein the inlet pipe is ( 7 ) located at the top of the duplex reactor, which is connected to the reactor shell ( 1 ); the exhaust pipe ( 8 ) is in the vicinity of a conical collection hood and connected to the reactor inner shell ( 2 ); the outlet pipe ( 3 ) is located in the upper part of the reactor, located in the lower part of the conical collection hood, and connected to the reactor inner shell ( 2 ). As illustrated in FIG. 2 , the honeycomb support frame ( 10 ) is located in the reactor inner shell 2 , which is filled with the resins loaded with microorganisms ( 11 ); the water distributor ( 6 ) is located at the bottom of the reactor inner shell ( 2 ); the backwash water outlet pipe ( 4 ) is above in each layer of the honeycomb support frame ( 10 ) and connected to the reactor inner shell ( 2 ); the backwash water inlet pipe ( 13 ) is located at the bottom of the water distributor ( 6 ) and is connected to the reactor shell; the aeration tube ( 12 ) is connected to the aeration head ( 5 ), and the aeration head ( 5 ) is located directly above the reactor water distributor ( 6 ).
[0042] As illustrated in FIG. 4 , a method for removal of tebuconazole includes the following operations.
[0043] Step 1. Providing the resins loaded with microorganisms:
[0044] (a) Culturing microorganisms (e.g., Sphingomonas paucimobilis ) by: inoculating Sphingomonas bacterium colonies from plates into culture media including beef peptone and keeping the culture media from light at temperature 28 degrees Celsius;
[0045] (b) Collecting microorganisms: separating Sphingomonas paucimobilis at a logarithmic growth phase from the culture media by centrifugation for 20 min with a speed of 5000 G; washing the Sphingomonas paucimobilis using a solution (pH=7.3) containing disodium hydrogen phosphate and potassium dihydrogen phosphate;
[0046] (c) Loading the microorganisms to the resins: placing the collected microorganisms into culture media containing minerals, adding the polystyrene resins to the culture media containing minerals and shaking the culture media containing minerals for 3-5 days to obtain the resins loaded with microorganisms;
[0047] (d) Filling in the resins: washing the resins loaded with microorganisms using deionized water and filling the resins into the double honeycomb support frame of the duplex reactor.
[0048] Step 2. Adding water: adjusting water flow and flow of the complementary nutrient solution (e.g., methanol solution), controlling the inlet water sample adjustment tank such that CODCr of water samples is of 25±5 mg/L, wherein tebuconazole concentration was 4.0±0.5 mg/L, allowing the water samples into the inlet pipe of the duplex reactor, and opening the aeration pump.
[0049] Step 3. Adsorption and bio-degradation of tebuconazole: allowing the water samples pass through multiple layers of the resins, removing tebuconazole by the resins, discharging adsorption of water from the outlet pipe, wherein, at the same time, microorganisms attached to the resins uses complementary nutrients and tebuconazole as a carbon source to degrade tebuconazole, the water samples were placed in the duplex reactor for about 30 minutes, CODCr in water samples was not greater than 15 mg/L, and the tebuconazole concentration was not greater than 0.1 mg/L.
[0050] Step 4. Backwash: 7 days after the bio-degradation, due to the situation that attached microorganisms metabolism on the resins result in death and loss of certain microorganisms, closing the feed line pumps, valves and outlet valves, opening valves of the backwash water inlet and the backwash water outlet pipe, backwashing the resins for about two minutes, placing the backwash water into the backwash water effluent collection tank, discharging the backwash water into a sewage treatment plant, closing the valves of the backwash water inlet pipe and backwash water inlet outlet pipe, opening the valve and the pump of the inlet water pipeline, the water inlet valve, and continuing to run operations.
Operating Results of Example 1
[0051]
[0000]
Running time (days)
1
2
3
4
5
6
7
Influent CODCr
25
28
27
23
29
21
27
(mg/L)
tebuconazole
3.7
3.9
4.2
3.7
4.4
4.5
4.3
concentration
(mg/L) in the
influent
CODCr (mg/L)
8
12
11
9
15
14
13
in effluent
tebuconazole
0.05
0.07
0.08
0.09
0.07
0.08
0.10
concentration
(mg/L) in the
effluent
Example 2
[0052] The processing system is used in Example 1.
[0053] Step 1. Providing the resins loaded with microorganisms:
[0054] (a) Culturing microorganisms (e.g., Sphingomonas paucimobilis ) by: inoculating microorganism colonies from plates into culture media including beef peptone and keeping the culture media from light, at temperature 28 degrees Celsius;
[0055] (b) Collecting microorganisms: separating the microorganisms at a logarithmic growth phase from the culture media by centrifugation for 20 min with a speed of 5000 G, washing the microorganisms using a solution (pH=7.3) containing disodium hydrogen phosphate and potassium dihydrogen phosphate;
[0056] (c) Loading the microorganisms to the resins: placing the collected microorganisms into culture media containing minerals, adding the polyacrylate resins to the culture media containing minerals and shaking the culture media containing minerals for 4 days to obtain the resins loaded with microorganisms;
[0057] (d) Filling in the resins: washing the resins loaded with the microorganisms using deionized water, and filling the resins into the double honeycomb support frame of the duplex reactor.
[0058] Step 2. Adding water: adjusting water flow and flow of the complementary nutrient solution (e.g., glucose solution), controlling the inlet water sample adjustment tank such that CODCr of water samples is of 40±5 mg/L, wherein tebuconazole concentration was 10.0±0.5 mg/L, allowing the water samples into the inlet pipe of the duplex reactor, and opening the aeration pump.
[0059] Step 3. Adsorption and bio-degradation of tebuconazole: allowing the water samples pass through multiple layers of the resins, removing tebuconazole by the resin, discharging adsorption of water from the outlet pipe, wherein, at the same time, microorganisms attached to the resins use complementary nutrients and tebuconazole a carbon source to degrade tebuconazole, and the water samples were placed in the duplex reactor for about 50 minutes, CODCr in water samples was not greater than 20 mg/L, and the tebuconazole concentration was not greater than 0.2 mg/L.
[0060] Step 4. Backwash: 8 days after the bio-degradation, due to the situations that attached microorganisms metabolism on the resins result in death and loss of certain microorganisms, closing the feed line pumps, valves and outlet valves, opening valves of the backwash water inlet and the backwash water outlet pipe, backwashing the resins for about three minutes, placing the backwash water into the backwash water effluent collection tank, discharging the backwash water into a sewage treatment plant, closing the valves of the backwash water inlet pipe and backwash water inlet outlet pipe, opening the valve and the pump of the inlet water pipeline, the water inlet valve, and continuing to run operations.
Operating Results of Example 2
[0061]
[0000]
Running time (days)
1
2
3
4
5
6
7
8
Influent
45
38
37
43
39
41
44
42
CODCr
(mg/L)
tebuconazole
9.7
9.9
10.2
9.8
10.4
10.5
10..3
10.1
concentration
(mg/L)
in the influent
CODCr (mg/L)
17
15
11
19
15
17
20
15
in effluent
tebuconazole
0.15
0.17
0.10
0.19
0.20
0.11
0.14
0.16
concentration
(mg/L)
in the effluent
Example 3
[0062] The processing system is used in Example 1.
[0063] Step 1. Providing the resins loaded with microorganisms:
[0064] (a) Culturing microorganisms (e.g., Sphingomonas paucimobilis ) by: inoculating microorganism colonies from plates into culture media including beef peptone and keeping the culture media from light at temperature 28 degrees Celsius;
[0065] (b) Collecting microorganisms: separating the microorganisms at a logarithmic growth phase from the culture media by centrifugation for 20 min with a speed of 5000 G, washing the microorganisms using a solution (pH=7.3) containing disodium hydrogen phosphate and potassium dihydrogen phosphate;
[0066] (c) Loading the microorganisms to the resins: placing the collected microorganisms into culture media containing minerals, adding the polystyrene resins to the culture media containing minerals and shaking the culture media containing minerals for 5 days to obtain the resins loaded with microorganisms;
[0067] (d) Filling in the resins: washing the resins loaded with microorganisms using deionized water, and filling the resins into the double honeycomb support frame of the duplex reactor.
[0068] Step 2. Adding water: adjusting water flow and flow of the complementary nutrient solution (e.g., sodium acetate solution), controlling the inlet water sample adjustment tank such that CODCr of water samples is of 60±5 mg/L, wherein tebuconazole concentration was 20.0±0.5 mg/L, allowing the water samples into the inlet pipe of the duplex reactor, and opening the aeration pump.
[0069] Step 3. Adsorption and bio-degradation of tebuconazole: allowing the water samples pass through multiple layers of the resins, removing tebuconazole by the resin, discharging adsorption of water from the outlet pipe, wherein, at the same time, microorganisms attached to the resins use complementary nutrients and tebuconazole as a carbon source to degrade tebuconazole, and the water samples were placed in the duplex reactor for about 80 minutes, CODCr in water samples was not greater than 25 mg/L, and the tebuconazole concentration was not greater than 0.3 mg/L.
[0070] Step 4. Backwash: 10 days after the bio-degradation, due to the situation that attached microorganisms metabolism on the resins result in death and loss of certain microorganisms, closing the feed line pumps, valves and outlet valves, opening valves of the backwash water inlet and the backwash water outlet pipe, backwashing the resins for about five minutes, placing the backwash water into the backwash water effluent collection tank, discharging the backwash water into a sewage treatment plant, closing the valves of the backwash water inlet pipe and backwash water inlet outlet pipe, opening the valve and the pump of the inlet water pipeline, and the water inlet valve, and continuing to run.
Operating Results of Example 3
[0071]
[0000]
Running time (days)
1
2
3
4
5
6
7
8
9
10
Influent
64
57
59
61
65
64
60
58
57
63
CODCr (mg/L)
tebuconazole
20.4
19.8
19.6
20.3
20.0
20.1
20.5
20.4
20.2
19.9
concentration
(mg/L) in the
influent
CODCr (mg/L)
19
21
23
19
25
22
23
15
18
24
in effluent
tebuconazole
0.21
0.19
0.18
0.24
0.27
0.23
0.30
0.26
0.29
0.30
concentration
(mg/L) in the
effluent
Example 4
[0072] The processing system is used in Example 1.
[0073] Step 1. Providing the resins loaded with microorganisms:
[0074] (a) Culturing microorganisms (e.g., Sphingomonas paucimobilis ): inoculating microorganism colonies from plates into culture media including beef peptone and keeping the culture media from light, at temperature 28 degrees Celsius;
[0075] (b) Collecting microorganisms: separating the microorganisms a logarithmic growth phase from the culture media by centrifugation for 20 min with a speed of 5000 G. washing the microorganisms using a solution (pH=7.3) containing disodium hydrogen phosphate and potassium dihydrogen phosphate;
[0076] (c) Loading the resins: placing the collected bacteria into culture media containing minerals, adding the polyacrylate resins to the culture media containing minerals and shaking the culture media containing minerals for 4 days to obtain the resins loaded with microorganisms;
[0077] (d) Filling in the resins: washing the resins loaded with microorganisms using deionized water, and filling the resins into the double honeycomb support frame of the duplex reactor.
[0078] Step 2. Adding water: adjusting water flow and flow of the complementary nutrient solution (e.g., ethanol solution), controlling the inlet water sample adjustment tank such that CODCr of water samples is of 80±5 mg/L, wherein tebuconazole concentration was 25.0±0.5 mg/L, allowing the water samples into the inlet pipe of the duplex reactor, and opening the aeration pump.
[0079] Step 3. Adsorption and bio-degradation of tebuconazole: allowing the water samples pass through multiple layers of the resins, removing tebuconazole by the resin, discharging adsorption of water from the outlet pipe, wherein, at the same time, microorganisms attached to the resins use complementary nutrients and tebuconazole as a carbon source, the bacteria degrade tebuconazole, and the water samples were placed in the duplex reactor for about 80 minutes, CODCr in water samples was not greater than 25 mg/L, and the tebuconazole concentration was not greater than 0.5 mg/L.
[0080] Step 4. Backwash: 9 days after the bio-degradation, due to the situation that attached microorganisms metabolism on the resins result in death and loss of certain microorganisms, closing the feed line pumps, valves and outlet valves, opening valves of the backwash water inlet and the backwash water outlet pipe, backwashing the resins for about four minutes, placing the backwash water into the backwash water effluent collection tank, discharging the backwash water into a sewage treatment plant, closing the valves of the backwash water inlet pipe and backwash water inlet outlet pipe, opening the valve and the pump of the inlet water pipeline, the water inlet valve, and continuing to run operations.
Operating Results of Example 4
[0081]
[0000]
Running time (days)
1
2
3
4
5
6
7
8
9
Influent CODCr
64
57
59
61
65
64
60
58
57
(mg/L)
tebuconazole
20.4
19.8
19.6
20.3
20.0
20.1
20.5
20.4
20.2
concentration
(mg/L) in the
influent
CODCr (mg/L)
19
21
23
19
25
22
23
15
18
in effluent
tebuconazole
0.31
0.39
0.24
0.50
0.35
0.43
0.30
0.22
0.40
concentration
(mg/L) in the
effluent | Implementations herein relate to systems and methods for removal of tebuconazole from water using a duplex reactor. Water samples containing tebuconazole enter a double sandwich of the duplex reactor, and then enter a reactor inner shell of the duplex reactor through a water distributor. In the duplex reactor, the tebuconazole is removed by adsorption resins loaded with microorganisms. After the removal, a concentration of the tebuconazole in adsorption effluent is below the standard limit of the national pesticide wastewater discharge. The microorganisms loaded on the resins use organic carbon (e.g., tebuconazole) in water as a carbon source and degrade tebuconazole that is absorbed by the resins. The systems and methods not only solve problems associated with conventional techniques (e.g., poor water quality fluctuations and lacking of time long degradation), but also address issues associated with resin adsorption methods (e.g., secondary pollution derived from resins regeneration). | 8 |
FIELD OF THE INVENTION
The field of this invention relates to the milling of tubulars extending through a main wellbore into a deviated wellbore after cementing in place.
BACKGROUND OF THE INVENTION
In the past, whipstocks have been used to create a window in a casing in a main wellbore for the initiation of a deviated wellbore which diverges from the original wellbore. After milling the window and drilling the deviated wellbore, a tubular is inserted through the window into the deviated wellbore. Prior completions have generally involved the absence of any cementing of the liner extending into the deviated wellbore or if cementing were done, it was terminated short of the window milled in the casing in the main wellbore. In those earlier techniques, since cement would not be allowed to come back from the deviated wellbore into the main wellbore, milling out the tubing from the main wellbore which extended into the deviated wellbore was not necessary if further production was required from the main wellbore. Completion techniques have evolved to the point where after milling the window and creating the deviated wellbore, the liner is placed through the window into the deviated wellbore and cemented. Thereafter, a milling operation is necessary to remove that portion of the liner in the main wellbore and to retrieve the whipstock, if it has not already been earlier retrieved.
FIGS. 1 and 2 indicate these procedures that had been previously required in view of the use of existing equipment, as just described. FIG. 1 illustrates a main wellbore 10 which has a deviated wellbore 12 already drilled through it. Inside of the main wellbore 10 is casing 14, which has already been milled through the use of a whipstock 16 and a milling tool (not shown). At the conclusion of the milling of the "window" 18 in the casing 14, a liner 20 is inserted into casing 14 and is diverted into window 18 into deviated wellbore 12, as shown in FIG. 1. In order to make the turn into deviated wellbore 12, the liner 20 winds up being wedged against one side of the casing 14, as shown in FIG. 1. Similarly, that same liner 20 in the deviated wellbore 12 also can become wedged against the uncased bore making up wellbore 12, as shown in FIG. 1.
After placement of the liner 20 into deviated wellbore 12, the deviated wellbore is cemented around the liner 20 up into the main wellbore 10. Thereafter, a milling tool 22 is employed to mill out the portion of the liner 20 that extends in wellbore 10. Thereafter, the whipstock 16 is removed. This procedure is illustrated in more detail in U.S. Pat. No. 5,301,760. FIG. 2 reflects the use of centralizers 24 in the deviated wellbore 12 to centralize the liner 20 therein. While the centralizers located in the deviated wellbore 12 help to centralize the liner 20, that portion of the liner 20 that extends into the wellbore 10 is still wedged firmly against the casing 14 within wellbore 10 due to the angular deflection of the liner 20.
There are many practical problems disclosed by the method in U.S. Pat. No. 5,301,760 that are not revealed in the patent. The biggest problem occurs when a milling tool such as 22 is employed to begin the milling operation. Typically, a "washover"-type milling tool is used which has cutting elements on the bottom and on the inside. This type of tool is called a washover tool because its purpose is to straddle the tubular object to be milled. This type of milling tool generally has no cutting elements on its exterior. Cutting elements on the exterior of the milling tool 22 would be undesirable since it would result in milling away of the wall of casing 14 in wellbore 10. The problem arises in the sense that with the liner 20 wedged up against the casing 14 in wellbore 10, the washover milling tool 22 cannot fully get around the upper end of the liner 20. Instead, as shown in FIG. 1, some milling goes on on the inboard side 26 of liner 20, while more complete milling takes place on the outboard side 28. The result of this uneven milling is that slivers are formed because segments of the inboard side 26 are not fully milled. Since segments of the inboard side are not fully milled, they retain additional structural strength which ultimately results in directing the milling tool 22 in a deviated path toward window 18. This is undesirable since continued milling with the milling tool 22 in a skewed or deviated position can result in unwanted milling of segment 30 of the casing 14, which is located below the window. FIG. 2 is intended to illustrate the formation of slivers and the skewing of the milling tool 22 when an attempt is made to use a washover tool over a liner 20 when the liner 20 is pressed rigidly against the casing 14. As a result of the milling process illustrated in FIG. 2, segment 32 while shown in the drawing is, in effect, fully milled away while only portions of segment 34 on the inboard side 26 is effectively milled due to the inability of the washover tool 22 to fully wash over the inboard side 26. Accordingly, as a result of the milling operation illustrated in the U.S. Pat. No. 5,301,760, slivers 36 are formed which subsequently must be fished out or further ground up before the whipstock 16 can be removed.
Accordingly, one of the several objectives of the method of the present invention is to facilitate the milling operation by providing mechanisms to keep the liner 20 away from the wall of the casing 14 to facilitate the washover milling operation. Additionally, it is a further object of the invention to facilitate the insertion of the liner through the use of a diverter. It is another object to employ a diverter of suitable dimensions to allow the washover mill to straddle it and ultimately latch into it so that any segments of cement or similar material or metal slivers which may be formed are caught within the washover tool when it is latched to the diverter. Ultimately, it is another object of the invention to be able to remove the diverter and thus provide a clear access to a packer which is further downhole in the main wellbore.
SUMMARY OF THE INVENTION
An apparatus and method of milling a liner extending from a deviated wellbore into a main wellbore is disclosed. The liner is inserted through a window and cemented in place with the cement extending back into the main wellbore. Mechanisms are provided on the liner to keep it away from the main wellbore casing wall to facilitate the proper operation of the washover tool. A top end taper is provided to help the washover tool reorient over the tubular liner if milling requires more than one trip into the well. A diverter is insertable prior to installation of the liner to assist in getting the liner to extend through a window. Upon milling through the liner, the washover tool straddles the diverter and latches into it to facilitate not only the removal of the diverter but also the entrapment of any debris created by the milling operation. Suitable sealing is provided with the diverter to keep the cement away from the latching mechanism during the cementing operation.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates a milling technique for a liner as shown and described in U.S. Pat. No. 5,301,760 without the use of a centralizer in the deviated wellbore.
FIG. 2 illustrates the same thing as FIG. 1 except centralizers are shown in the deviated wellbore and the result of a milling operation with a washover mill leaving slivers is illustrated.
FIG. 3 illustrates schematically the apparatus and method of the present invention, showing the liner with a mechanism to keep it away from the casing wall.
FIG. 4 is a sectional view along lines 4--4 of FIG. 3, showing a longitudinal rib structure as the technique for distancing the liner from the casing wall.
FIG. 5 is an alternative embodiment to FIG. 4, showing a plurality of protrusions added to the exterior surface of the liner as a way of keeping the liner from the casing wall in the main wellbore.
FIG. 6 is a detailed sectional drawing showing the diverter in position supported by a wellbore packer prior to insertion of the liner.
FIG. 7 is the view of FIG. 6, showing the liner inserted and fully cemented.
FIG. 8 is the view of FIG. 7, after the washover pipe has cut through the liner portion extending into the main wellbore and has passed by the latching mechanism of the diverter.
FIG. 9 is a view after the washover tool effectively removes the diverter from the packer in the main wellbore.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 3 schematically indicates the tubular liner 40, extending from the main wellbore 42 into the deviated wellbore 44. The main wellbore 42 has a casing 46 into which a window 48 has already been milled. A diverter 50, and generally indicated in the drawing as D, is located in the main wellbore 42 and supported by a packer 52, also referred to as P in the drawing of FIG. 3. The diverter 50 is inserted into the main wellbore 42 after removal of the whipstock at the conclusion of the milling of the window 48 in a manner well-known in the art. The diverter 50 is used in the position shown in FIG. 6 to deflect the liner 40 as it is inserted in the main wellbore 42 to orient its leading edge into the deviated wellbore 44, as shown in FIGS. 6 and 7.
One of the features of the present invention is the use of exterior spacers, such as ribs 54. As shown in the cross-section of FIG. 4, one embodiment is the use of longitudinal ribs disposed at 90° intervals continuously or discontinuously on the outer periphery of the liner 40 such that they extend into the main wellbore 42, thus keeping the liner 40 away from the casing 46, as shown in FIG. 3. Ribs 54 may be also circumferentially extending in the main wellbore 42 and can be of a construction shown in item 24 of FIG. 2. The ribs need not be continuous and can be at different spacing than 90°. Any type of spacer located so as to keep the upper segment of liner 40 away from the casing 46, as shown in FIG. 3, is within the scope of the invention. The liner 40 is encased in a sealer such as a cementitious material 56. Material 56 fills the voids around any spacer, such as ribs 54. The cementitious material extends into the main wellbore 42. As shown in FIG. 7, the cementitious material 56 is placed in the main and deviated wellbores 42 and 46, respectively, with the diverter 50 in position. Diverter 50 has a seal or seals 58 which retain the cementitious material 56 above a centralizer 60. The outside diameter of the diverter 50 is smaller than the diameter of the casing 46 within the mail wellbore 42.
Referring now to FIG. 5, an alternative embodiment to the ribbed structure illustrated in FIG. 4 is shown. In FIG. 5, a series of protrusions which can be orderly or randomly arranged are placed on the outer periphery of the liner 40, particularly in the zone extending into the main wellbore 42 to, again, keep the upper end 62 away from the casing 46. A known running tool (not shown) can be used to facilitate the lowering and insertion of the liner 40 into the position shown in FIG. 3. Such a known running tool can leave a segment behind after release from the liner 40 which includes a taper 64. The significance of this taper 64 at the upper end 62 of the liner 40 will be explained below. It should be noted that it is within the purview of the invention to use a wide variety of spacing mechanisms on the outer periphery of the liner 40 in the portion that extends into the main wellbore 42 to keep that portion away from the casing 46. Thus, many types of mechanisms can be employed as a spacing mechanism to accomplish the objective without departing from the spirit of the invention; for example, apart from the longitudinal ribs and random or orderly protrusions, other devices can be used such as a helix, discrete rods, spaced transverse rings, as long as the objective of keeping the upper end 62 away from the rigid contact with casing 46 is accomplished. Whatever mechanism is employed, it should not interfere with the free flow of the cementitious material 56 which must be placed around the outer periphery of the liner 40 in the deviated wellbore 44 and on up to the upper end 62 of the liner 40, disposed within the main wellbore 42.
By employment of the spacing mechanism such as ribs 54 or other protrusions 66, illustrated in FIG. 5, the washover tool 68 (see FIG. 8) can easily straddle the liner as it properly needs to do so that cutting can be accomplished with minimal creation of slivers which had occurred employing the washover tool in the methods revealed in U.S. Pat. No. 5,301,760, as illustrated in FIGS. 1 and 2. By moving the upper end 62 away from the wall, the internal cutters 70 (see FIG. 8) can evenly cut away the protrusion and then that portion of the liner 40 within the main wellbore 42. Since the washover tool 68 is not eccentrically disposed with respect to the liner 40 adjacent the upper end 62 as was the case in FIGS. 1 and 2, slivers are not a problem. In effect, the washover tool 68 cleanly mills away the ribs, such as 54. Eventually, the washover tool 68 begins to cut through the wall of the liner 40. However, by then it has cleanly encircled the upper end 62 of liner 40 and can then make meaningful progress in a direction straight ahead toward a position where the diverter 50 is fully straddled, as shown in FIG. 8. Since the upper end 62 serves as a guide for the washover tool 68 because milling is cleanly going on around the periphery of the upper end 62, the tendency of the liner 40 to misdirect the washover tool 68 toward window 48, which was present in the milling techniques illustrated in FIGS. 1 and 2, is removed. Even if the washover tool 68 must be replaced prior to the conclusion of the entire milling operation, the same results can be obtained without risk of inadvertent milling of any portion of the casing 46 in the region 72 below the window 48. What occurs if the washover tool 68 must be removed before the conclusion of the milling is that the spacing mechanism, such as ribs 54 or protrusions 66, have been milled from a portion of the upper end 62. Upon initial removal of the washover tool 68 before the conclusion of the milling operation, the upper end 62 of the liner 40 will flex toward the casing 46 in the main wellbore 42. However, because of the taper 64 which has been deposited at the upper end 62 when the release has occurred from the running tool (not shown), the newly inserted washover tool 68 can readily get behind the upper end 62 of the liner 40 to once again resume the milling operation with the upper end 62 fully enclosed within the washover tool 68 as the milling continues. Again, the presence of the liner 40 acts as a guide to keep the initial progress of the washover tool 68 oriented in the direction of main wellbore 42 until actual cutting through the liner wall is accomplished, as shown in FIG. 8. Thereafter, the washover tool 68 progresses to the point where an internal recess 74 passes over and beyond a latch mechanism such as spring-loaded dogs 76. As shown in FIG. 8, the trimmed section of liner 78 is effectively trapped within the washover tool 68 above the diverter 50. A comparison of FIGS. 7 and 8 reveals that the use of the washover tool 68 has resulted in the milling away of the seal 58 as well as the centralizer 60. Although only the liner section 78 is shown to be within the washover tool 68 in FIG. 8, those skilled in the art can appreciate that other metal fragments or portions of the cementitious material 56 can also be disposed within the washover tool 68 above the diverter 50. For example, the ribs 54 (see FIG. 4) or protrusions 66 (see FIG. 5) are also milled by the cutters 70 and captured within the body of the washover tool 68.
At the conclusion of the milling operation, the washover tool 68 is pulled up, bringing up recess 74 until dogs 76 come into alignment with recess 74, thereby facilitating the release of the diverter tool 50 from the packer 80 (see FIGS. 8 and 9). What remains is a deviated wellbore 44 that is lined with a cementitious material or equivalent 56 disposed around the cut-off liner 40 which terminates at window 48. In the main wellbore 42, the casing 46 has a clear path down to packer 80. This facilitates subsequent operations in the main wellbore 42 below packer 80, if necessary, or removal of packer 80. Simultaneously, production can proceed from the deviated wellbore 44. This process can be repeated many times to create multiple deviated wellbores, such as 44, using the equipment above described.
Those skilled in the art can appreciate that the method as above described offers unique advantages over prior techniques. Since the liner is held, at least initially, away from the wall of the casing 46 at the onset of milling with the washover tool 68, proper operation of the washover tool 68 minimizes the formation of slivers of the liner 40 during the milling operation. Also, the tendency of the liner 40 to pull the washover tool 68 laterally toward the window 48, due to the uneven milling which occurred with the prior designs, is eliminated. Instead, the washover tool 68 proceeds to initially grind the cementitious material 56, as well as any projections or protrusions, such as 54 or 66, and ultimately slices cleanly through the liner 40 as it approaches the area of window 48. Other types of mills may be used without departing from the spirit of the invention.
The diverter 50 is installed after removal of the whipstock. Generally, to withstand the forces applied during the milling of the window 48, the whipstock (not shown) must be full-size or close thereto. The diverter 50, which does not need to withstand loads comparable to those delivered during the milling of a window 48, can be substantially smaller than a whipstock. The function of the diverter is to direct the liner 40 into the window 48 on initial insertion. This minimizes the need to twist or turn the liner 40 to get it to advance into the window 48. Twisting or turning the liner 40 can be disadvantageous, particularly if the spacing devices, such as ribs 54 or protrusions 66, are used. The possibility can exist for sticking the liner 40 in an attempt to guide it into the lateral wellbore 44. Accordingly, the use of the diverter 50, which is sufficiently undersized when compared to the inside diameter of the casing 46 in the main wellbore 42, accomplishes not only the objective of easily guiding the liner 40 into the window 48, but also presents a profile for the diverter 50 which will allow the washover tool 68 to advance over it, as shown in FIG. 8, for ultimate capture of the milling byproducts and the removal of such byproducts in conjunction with the removal of the diverter 50 from the wellbore. The packer 80 can remain in the wellbore for further future downhole operations. Additionally, even if multiple trips with one or more washover tools 68 become necessary and the upper end 62 flexes back toward the casing 46 because some of the ribs 54 or protrusions 66 have been milled away, on a second or subsequent trip, the washover tool 68 can easily seek the taper 64 and move the upper end 62 away from the wall so that milling can then resume with the washover tool 68 comfortably straddling the upper end 62 of the liner 40.
The foregoing disclosure and description of the invention are illustrative and explanatory thereof, and various changes in the size, shape and materials, as well as in the details of the illustrated construction, may be made without departing from the spirit of the invention. | An apparatus and method of milling a liner extending from a deviated wellbore into a main wellbore is disclosed. The liner is inserted through a window and cemented in place with the cement extending back into the main wellbore. Mechanisms are provided on the liner to keep it away from the main wellbore casing wall to facilitate the proper operation of the washover tool. A top end taper is provided to help the washover tool reorient over the tubular liner if milling requires more than one trip into the well. A diverter is insertable prior to installation of the liner to assist in getting the liner to extend through a window. Upon milling through the liner, the washover tool straddles the diverter and latches into it to facilitate not only the removal of the diverter but also the entrapment of any debris created by the milling operation. Suitable sealing is provided with the diverter to keep the cement away from the latching mechanism during the cementing operation. | 4 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to a valve with a rotary stopper and a water-treatment plant comprising such a valve.
[0002] The invention relates notably to motorized three-way valves (i.e. with three connection interfaces) and to water-treatment plants for seawater or brackish water by reverse osmosis which incorporate such valves.
[0003] In the present application, unless explicitly or implicitly indicated to the contrary, the terms “cylinder” and “cylindrical” refer to a body delimited by—or a shape or a surface engendered by—parallel straight lines resting on a closed contour which may be circular.
DESCRIPTION OF THE PRIOR ART
[0004] In plants for desalinating seawater by reverse osmosis, the water to be treated is delivered to the inlet of a filtration device at an inlet pressure that is higher than the osmotic pressure of the water; usually, since the osmotic pressure of salt water is 25 bar, the water supply pressure at the inlet of the filter is at least equal to 25 bar, for example of the order of 30 to 100 bar, in particular of the order of 60 to 80 bar; recovered at the outlet of the filter is a concentrate of water called “brine” on the one hand, and an ultrafiltrate of desalinated water (which is at a pressure close to atmospheric pressure) on the other hand; the pressure of the concentrate at the outlet of the filter is usually not much less than the supply pressure of water to be desalinated, for example less than the supply pressure by a value of the order of 1 to 5 bar, since the pressure drop in the filter is slight.
[0005] Patents FR 2342252 and U.S. Pat. No. 4,124,488 describe a plant for purifying water by reverse osmosis comprising a piston pump delivering the pressurized water to the inlet of a reverse osmosis module (ROM) and receiving the pressurized brine leaving the module ROM via a controlled valve, in order to use the energy of the pressurized brine to compress/pressurize the water to be desalinated.
[0006] The piston of the pump is driven in an alternating translation movement by an electric motor.
[0007] According to one embodiment, a rear portion of the piston has two peripheral longitudinal grooves such that, the piston also being driven in an angular oscillation movement, the piston forms a stopper placing a chamber of the pump extending behind the piston in communication either with a duct for conveying brine originating from the ROM or with a discharge duct.
[0008] One drawback of this plant is that causing the piston to oscillate angularly requires causing the pump body to oscillate angularly, which causes an unnecessary consumption of energy. This causing of the pump body to oscillate angularly requires the pump to be connected to the circuits of the plant via flexible connectors, which has implementation problems notably because of the pressure of the water circulating in the plant.
[0009] Patents EP 1194691 and U.S. Pat. No. 6,652,741 describe a seawater treatment plant in which several piston pumps are driven by means of a hydraulic actuator and are controlled to ensure a stoppage time of each piston, at each end of stroke of the piston in question, and to ensure a constant total flow rate.
[0010] The intake of brine into a chamber of each pump for the recovery of energy from the “concentrate”; and the subsequent discharge of this concentrate, are carried out by a three-way valve or directional-flow valve.
[0011] This device, the valve or directional-flow valve, must satisfy several requirements: it must allow the passage of a high flow rate of water without causing considerable pressure losses; it must be designed to withstand the high pressure (of the order of 60 to 80 bar for example) of the brine leaving the osmotic filters; moreover, when no provision is made to stop the pistons of the pumps at the end of the stroke for a sufficient period, this device must then switch from a configuration for taking water into the pump to a configuration for discharging water from the pump, substantially instantaneously, at the precise moment when the pump piston in question stops at the end of the stroke.
[0012] The known valves and directional-flow valves do not satisfy these requirements simple and reliably.
SUMMARY OF THE INVENTION
[0013] One object of the invention is to propose a valve or directional-flow valve that is simple to manufacture and install, having a long service life and high reliability, causing little pressure loss, making it possible to close in a substantially sealed manner a duct for conveying brine connecting a filtration module to a piston pump and being able to change—“switchover”—, substantially instantaneously, from a configuration of supply in which the valve is traversed by a current of pressurized brine supplying the pump, to a configuration of discharging/emptying in which the valve is traversed by a current of brine discharged from the pump.
[0014] One object of the invention is to propose a valve or directional-flow valve that is improved and/or that remedies, at least in part, the shortcomings or drawbacks of the known valves and directional-flow valves.
[0015] One object of the invention is to propose a plant for treating seawater or brackish water comprising a pump and a three-way valve for supplying the pump with brine and for discharging the brine, that is improved and/or that remedies, at least in part, the shortcomings or drawbacks of the known water-treatment plants.
[0016] According to one aspect, the invention proposes a valve comprising:
a valve body delimiting a cavity, the body being provided/pierced with a first orifice allowing water to enter the cavity, with a second orifice allowing water to be discharged from the cavity, and a third orifice making it possible to place the cavity and a chamber of a pump in communication; a stopper mounted so as to be able to rotate inside the cavity, the stopper comprising a recess on its outer face, this recess helping, with the body to form/delimit a passageway—which rotates with the stopper—allowing water to travel between the first and third orifices in first angular positions of the stopper—corresponding to a configuration of the valve allowing the pump to be supplied—, said passageway also allowing water to travel between the second and third orifices in second angular positions of the stopper—corresponding to a configuration of the valve allowing the pump to be emptied; a first sealing device making it possible to stop in a substantially watertight manner the first orifice by the stopper in said second angular positions of the stopper; and a second sealing device making it possible to stop in a substantially watertight manner the second orifice by the stopper in said first angular positions of the stopper.
[0021] Notably when the outer face of the stopper is cylindrical, the recess may take the shape of a groove or flat extending along an axis orthogonal to the axis of revolution/rotation of the stopper, and have a width that is substantially/not much smaller than the diameter of the first and second orifices.
[0022] Preferably, in addition to said recess—first recess—said passageway comprises a second recess on the periphery/surface of the stopper, in particular a second recess of substantially annular shape which extends—at least in part—facing the third orifice, and a channel hollowed out in the stopper and connecting said first and second recesses.
[0023] The cross section of this channel may be not much smaller, equal or greater, than that of the first and second orifices in order to limit the pressure losses caused by the passage of the water in this channel and consequently in the valve.
[0024] In other words, and according to another aspect of the invention, what is proposed is a valve comprising a body delimiting a cavity and pierced with three orifices, and a stopper—or plug—mounted so as to rotate inside the body; the body comprises two housings leading into the cavity and surrounding respectively two of the three orifices; the valve also comprises two sealing members respectively placed slidingly in the two housings, and two pressing devices making it possible respectively to press the two sealing members against the stopper, in order to provide a substantially watertight stopping of a first of the three orifices, by the stopper, in second angular positions of the stopper and in order to provide a substantially watertight stopping of a second of the three orifices, by the stopper, in first angular positions of the stopper—distinct from the second angular positions.
[0025] According to a preferred embodiment, the housings take the shape of annular slots and the sealing members have an annular—or tubular—shape adapted to the shape of the portion of the stopper against which they are pressed, in particular a shape cut away like a bevel on a radius corresponding to the radius of a cylindrical portion of the stopper.
[0026] Preferably, each of the pressing devices comprises a channel, in particular several channels, which connect(s) one end of the housing in question that is opposite to the end (of the housing in question) that opens into the cavity: the pressing device associated with the sealing member surrounding a first of the orifices comprises at least one channel connecting the non-open end of the housing in question to a sleeve for connecting the valve to a duct conveying the water coming from a filtration module, while the pressing device associated with the sealing member surrounding a second of the orifices comprises at least one channel connecting the non-open end of the housing in question to the cavity.
[0027] These channels make it possible to place at equal pressure the non-open end of the housing in question and the duct conveying the water coming from the filtration module, respectively the cavity, and consequently make it possible to press against the stopper the “profiled” end of each of the sliding sealing members, notably when these members have a reduced thickness in their annular portion flush with the surface delimiting the cavity.
[0028] Moreover, accordingly, each of the pressing devices may comprise an elastically deformable member, such as a spring, placed in the corresponding housing, between the non-open end of the housing and the end of the corresponding sealing member, in order to keep the stopper and the sealing member in mutual contact when the valve is not operated and when no water current passes through it.
[0029] According to other preferred features:
the first and second orifices are facing one another, aligned along an axis that is (substantially) orthogonal to the axis of revolution of the cavity—which corresponds to the axis of rotation of the stopper—, these two axes being (substantially) coplanar; the valve body is pierced with two other orifices—fourth and fifth orifices—which face one another, aligned along an axis that is (substantially) indistinguishable from the axis of revolution of the cavity, and the stopper is secured in rotation to a drive shaft extending through these two orifices.
[0032] According to another aspect of the invention, a water-treatment plant is proposed comprising a water-filtration module, a pump with a piston, a motor, a mechanism for the driving of the pump by the motor, and a three-way valve with a rotary plug as described in the present application, the valve being fitted to a duct connecting the pump to the filtration module, the stopper of the valve being rotated substantially continuously by the motor, in synchronism with the pump.
[0033] According one embodiment, the stopper is driven so as to rotate one rotation when the piston of the pump makes a complete cycle, i.e. one stroke in one direction and one return stroke.
[0034] The continuous rotation of the stopper, usually with a substantially constant rotation speed, and the features of the stopper allowing the valve to switch substantially instantaneously from a supply configuration—for supplying the pump—with pressurized brine to a configuration for discharging the brine, in particular when the respective diameters of the first and second orifices are equal and that the depth of the first recess is equal to the difference between the radius of the stopper—in line with this recess—and the radius of the orifices.
[0035] According to one embodiment, the stopper provides a “total” closure of the valve for only two determined angular positions of the stopper: in each of these positions, the stopper closes the passageway between the first and third orifices and the passageway between the second and third orifices—and also the passageway between the first and second orifices.
[0036] In other words, according to this embodiment, the first angular positions of the stopper are adjacent so as to form a first continuous angular range of first angular positions of the stopper, which extends substantially over 180° (angle degrees), and the second angular positions of the stopper are also adjacent so as to form a second continuous angular range of second angular positions of the stopper, which also extends over 180°.
[0037] Other aspects, features and advantages of the invention will appear in the following description which refers to the appended figures and illustrates, without being in any way limiting, preferred embodiments of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0038] FIG. 1 is a diagram of a water-treatment plant according to one embodiment of the invention.
[0039] FIG. 2 is a schematic view in perspective of a valve according to one embodiment of the invention, of which the stopper is in the closed position of the valve, with partial cutaway: in this figure, as in FIGS. 4 to 6 , all that appears is the portion of the valve body extending under the plane containing the longitudinal axis of the body—and of the rotor—and the axis passing through the centers of the first and second orifices, the other portion of the body extending above this plane being “cut away” (not shown) in order to make it possible to view the rotor of the valve.
[0040] FIG. 3 is a schematic view in perspective of the rotor—including the stopper—of the valve illustrated in FIGS. 2 and 4 to 11 .
[0041] FIGS. 4 to 6 are schematic views in perspective similar to FIG. 2 , which show the rotor of the valve in other angular positions.
[0042] FIG. 7 is a view in longitudinal section of the valve along a first sectional plane containing the axis of two sleeves for connecting the valve to a filtration module—for one of the sleeves—and to a discharge circuit—for the second sleeve.
[0043] FIG. 8 is a view in longitudinal section of the valve along a second sectional plane perpendicular to the first and containing the axis of a third sleeve for connecting the valve to a piston pump.
[0044] FIG. 9 is a view in cross section of the valve along a third sectional plane perpendicular to the first two and containing the axis of the third connecting sleeve: this figure is a view along IX-IX of FIG. 7 .
[0045] FIG. 10 is a view in longitudinal section along the first sectional plane illustrating, on an enlarged scale, the sleeve for connecting the valve of FIGS. 2 and 4 to 11 to the discharge circuit.
[0046] FIG. 11 is a view in longitudinal section along the first sectional plane illustrating, on a larger scale, the sleeve for connecting the valve of FIGS. 2 and 4 to 11 to the filtration module.
[0047] FIG. 12 is a view in section along the first sectional plane illustrating, on a larger scale, another embodiment of the sealing device fitted to the sleeve for connecting the valve to a filtration module.
DETAILED DESCRIPTION OF THE INVENTION
[0048] Unless explicitly or implicitly indicated to the contrary, elements or members that are—structurally or functionally—identical or similar are indicated by identical references on the various figures.
[0049] With reference to FIG. 1 , the water-treatment plant comprises a water-filtration module 15 , a piston pump 27 , an electric motor 10 , a mechanism 11 for driving the pump via the output shaft 30 of the motor, and a three-way valve 24 with rotary plug.
[0050] The pump 27 comprises a body 13 delimiting a cylindrical cavity 16 , 17 inside which the piston 14 of the pump is driven in alternating translation 28 , the piston separating the cavity into two chambers: a first chamber 16 receiving the brine discharged from the module 15 , and a second chamber 17 receiving the water to be pumped and to be delivered under pressure to the module 15 .
[0051] The piston 14 is connected by a rod 12 to the mechanism 11 .
[0052] The pump 27 receives the water to be pumped delivered by a water-conveying duct 18 fitted with an inlet valve element 19 (nonreturn valve element).
[0053] The water pressurized by the pump 27 is conveyed to the module 15 by a duct 20 fitted with a delivery valve element 21 (nonreturn valve element).
[0054] The water (fresh water) filtered by the module 15 leaves the latter through a duct 22 , while the brine is conveyed by a duct 23 fitted with the valve 24 , from the module 15 to the “energy recovery” chamber 16 of the pump 27 .
[0055] The valve 24 is also connected to a duct 25 through which the brine is discharged from the chamber 16 at the end of each compression stroke of the piston 14 of the pump 27 during the stroke—in the reverse direction—of the piston 14 allowing the chamber 17 to be filled by the water to be pumped.
[0056] The transition from one configuration of the valve 24 allowing the passage of the brine originating from the module 15 to the chamber 16 , to a configuration of the valve allowing the discharge of the brine from the chamber 16 , results from the rotation 29 of the plug—i.e. of the stopper—of the valve.
[0057] The substantially continuous rotation of the stopper of the valve results from the driving of the stopper by the motor, in synchronism with the pump, by means of a shaft 26 for driving the stopper, this shaft 26 being connected for this purpose to the mechanism 11 .
[0058] With reference to FIGS. 2 and 4 to 9 , the valve 24 comprises a body 40 delimiting a cavity 41 .
[0059] The body 40 comprises a tubular central part 42 extending along an axis 43 , two circular flanges 44 and 45 placed and attached—by welding for example—at the two longitudinal ends of the central part 42 , and two parts 46 and 47 respectively attached to the flanges 44 , 45 by screws (not shown) for example.
[0060] Each part 46 , 47 is in the form of a thick disk and has a circular central orifice; a shaft 48 with an axis 43 extends through these two bored orifices, this shaft being secured in rotation to the stopper or plug 49 of the valve.
[0061] The body 40 also comprises two parts 50 and 51 respectively attached to the parts 46 , 47 by screws (not shown), each part 50 , 51 being in the form of a thick disk, with an external diameter smaller than that of the parts 46 , 47 and having a central circular orifice aligned with those of the parts 46 , 47 and through which the shaft 48 extends.
[0062] The tubular collar 42 of the body is pierced with three circular orifices: a first orifice 60 allowing water to be inserted into the cavity 41 , a second orifice 61 allowing water to be discharged from the cavity, and a third orifice 62 making it possible to place the cavity 41 and the chamber (reference 16 , FIG. 1 ) of the pump in communication.
[0063] For the connection of the valve to the duct (reference 23 , FIG. 1 ) conveying the brine originating from the filter 15 , the body comprises a first tubular sleeve 63 extending in line with the orifice 60 .
[0064] For the connection of the valve to the duct (reference 25 , FIG. 1 ) for discharging the brine, the body comprises a second tubular sleeve 64 extending in line with the orifice 61 .
[0065] For the connection of the valve to the duct (reference 23 , FIG. 1 ) for conveying the brine between the valve and the pump, the body comprises a third tubular sleeve 65 extending in line with the orifice 62 .
[0066] It can be seen in FIGS. 7 to 9 that each of these three sleeves is attached to the tubular part 42 by a first of its ends, for example by welding, and is furnished with a connecting flange 66 close to its second end.
[0067] The sleeves 63 and 64 are coaxial: they extend along an axis 67 perpendicular to the axis 43 and intersecting the latter; the sleeve 65 extends along an axis 68 which is also perpendicular to the axis 43 and intersects the latter, the axes 67 and 68 being orthogonal without being secant.
[0068] With reference to FIGS. 2 to 6 in particular, the rotor 70 of the valve comprises a central portion forming the plug 49 and two end portions extending on either side of the plug and forming two shaft ends 48 ; these three coaxial portions, with an axis 43 , can form a single part obtained by machining of a metal blank, for example, or else may consist of several parts fixed together.
[0069] It can be seen in FIGS. 2 and 4 to 8 that the stopper 49 is mounted so as to be able to rotate inside the cavity 41 of the valve body; accordingly, the rotor 70 is mounted in the bearings formed in the parts 46 , 47 , 50 , 51 by means of two rolling bearings 71 , 72 (ball bearings for example) fitted onto bearing surfaces formed by the shaft 48 .
[0070] With reference to FIGS. 2 to 6 in particular, the stopper consists essentially of a first portion 73 delimited by a cylindrical casing with an axis 43 and a radius 75 (see FIG. 9 ), and of a second cylindrical portion 74 with an axis 43 and radius 76 (see FIG. 8 ) which extends from the first portion 73 .
[0071] The radius 75 of the portion 73 is chosen to be slightly less than the radius 80 (see FIG. 8 ) of the cavity 41 , for example smaller than the latter by the order of 0.1 millimeter (mm) when the radius 80 is of the order of 100 mm, so as to define a very slight clearance between the peripheral surface of the portion 73 of the stopper and the wall 42 delimiting the cavity 41 .
[0072] The radius 76 of the portion 74 is chosen to be smaller than the radius 80 of the cavity 41 , for example close to the radius common to the orifices 60 to 62 , so that the portion 74 delimits with the wall 42 an annular space 79 —or second recess—allowing water to enter the valve—or leave the latter—through the orifice 62 ; for this purpose, the portion 74 of the stopper—and the volume 79 —preferably extend over a length at least equal to the diameter of the orifice 62 which opens into the volume 79 .
[0073] As illustrated notably in FIGS. 2 to 4 , 7 and 9 , the portion 73 of the stopper 49 comprises a recess 77 on its outer cylindrical face 90 .
[0074] This recess in the form of a groove or flat extends along an axis 91 orthogonal to the axis 43 of revolution/rotation of the stopper, and has a width 92 slightly smaller than the diameter of the first and second orifices 60 , 61 .
[0075] The depth 81 of the first recess 77 is substantially equal to the difference between the radius 75 of the stopper—in line with this recess—and the common (identical) radius of the orifices 60 , 61 .
[0076] The recess 77 helps—with the body—to delimit a passageway—which rotates with the stopper—allowing water to travel between the first and third orifices in the first angular positions of the stopper, which corresponds to a configuration of the valve illustrated in FIG. 4 and allowing the pump to be supplied.
[0077] Accordingly, a channel 78 is formed in the stopper and connects the recesses 77 and 79 as illustrated in FIGS. 2 to 4 and 7 in particular.
[0078] The cross section of this channel 78 is preferably at least close to that of the first and second orifices 60 , 61 and/or of that of the groove 77 , in order to limit the pressure losses caused by the water entering the valve.
[0079] The passageway formed by the recesses 77 , 79 and by the channel 78 also allows water to travel between the second and third orifices 61 , 62 in second angular positions of the stopper—corresponding to a configuration of the valve allowing the pump to be discharged—which are illustrated in FIGS. 6 and 9 in particular.
[0080] The valve also comprises two sealing devices making it possible respectively to achieve a substantially water-tight stopping of the first orifice 60 by the stopper in said second angular positions of the stopper, i.e. in the discharge position, and to ensure a substantially watertight stopping of the second orifice 61 by the stopper in said first angular positions of the stopper, i.e. in the position of supplying the pump with water.
[0081] Accordingly, as illustrated in FIGS. 10 and 11 , the body comprises two housings opening into the cavity 41 and surrounding respectively the two orifices 60 , 61 , and two sealing members respectively placed slidingly in the two housings.
[0082] A bush 93 , 94 is fitted respectively into each of the sleeves 63 , 64 with the axis 67 .
[0083] With respect to the sleeve 63 , in FIG. 11 , an outer cylindrical face 95 of the bush 93 extends coaxially to an inner cylindrical face 96 of the sleeve 63 , facing the latter, so as to delimit a housing 97 receiving a sliding sealing ring 98 and a seal 99 .
[0084] With respect to the sleeve 64 , in FIG. 10 , an outer cylindrical face 101 of the bush 94 extends coaxially to an inner cylindrical face 102 of the sleeve 64 , facing the latter, so as to delimit a housing 103 receiving a sliding sealing ring 104 and a seal 105 .
[0085] The housings 97 , 103 take the form of annular slots and the sealing members 98 , 104 have an annular—or tubular—shape adapted to the dimensions of the housings and to the shape of the portion of the stopper against which they are pressed: each sealing ring 98 , 104 has, at its end 110 , 111 being flush in the cavity 41 , a shape that is cut away according to a radius corresponding to the radius of the cylindrical portion 73 of the stopper.
[0086] A pressing device makes it possible to press the sealing ring 98 against the stopper, in order to ensure a substantially watertight stopping of the first orifice 60 , by the stopper, in angular positions of the stopper in which no portion of the groove 77 is facing this orifice.
[0087] A similar pressing device makes it possible to press the sealing ring 104 against the stopper, in order to ensure a substantially watertight stopping of the second orifice 61 , by the stopper, in angular positions of the stopper in which no portion of the groove 77 is facing this orifice.
[0088] Each of the pressing devices comprises several channels which connect one end (of the housing in question) that is opposite to the end of the housing in question that opens into the cavity, upstream—with reference to the direction of flow of the water in the valve—of the orifice in question: the pressing device associated with the sealing member 98 surrounding the first orifice 60 comprises four channels 100 distributed angularly about the axis 67 , each connecting the non-open end of the housing 97 to the inner face of the bush 93 of the sleeve 63 .
[0089] Similarly, the pressing device associated with the sealing member 104 surrounding the second orifice 61 comprises four channels 106 distributed angularly about the axis 67 and parallel with the latter, which are formed inside the sleeve 64 and each link the non-open end of the housing 103 to the cavity 41 .
[0090] The channels 100 make it possible to place the non-open end of the housing 97 and the duct conveying the water coming from the filtration module at equal pressure.
[0091] The channels 100 consequently make it possible to press against the stopper 49 the “profiled” end of each of the sliding sealing member 98 , because of the difference between the water pressures that are applied to the two opposite ends of the member 98 .
[0092] Similarly, the channels 106 make it possible to place the non-open end of the housing 103 and the cavity 41 at equal pressure and consequently make it possible to press the “profiled” end of each of the sliding sealing member 104 against the stopper, because of the difference between the pressures that are applied to the two opposite ends of the member 104 .
[0093] In the embodiment illustrated in FIG. 12 , the sealing member 98 comprises a first annular portion 980 having a first thickness 981 and of which one end is flush with the surface of the body delimiting the cavity 41 .
[0094] The member 98 comprises a second annular portion 982 coaxial with—and extending—the first annular portion 980 .
[0095] This second portion, which extends facing—and in the vicinity of—the non-open end of the housing 97 and of the channels 100 , has a thickness 983 greater than the thickness 981 so that the ring 98 is pushed back toward the stopper when its two longitudinal ends are subjected to the same pressure.
[0096] In order to prevent (or limit) water getting into the interstices extending between the ring 98 and the housing 97 in which the ring can slide, each of the annular portions 980 , 982 of the ring is furnished with an annular housing—like that referenced 984 —receiving a sealing-ring member (not shown).
[0097] Moreover, an elastically deformable member 120 , in the form of a ring forming a spring, is placed in the housing 97 receiving the ring 98 , between the non-open end of the housing 97 and the end of the portion 982 of the ring 98 .
[0098] The elastic ring 120 is arranged to keep in mutual contact the stopper 49 and the end 110 of the sealing ring 98 when the valve is not operated and/or when no water current passes through it. | The invention relates to a valve ( 24 ) comprising: a body ( 40 ) defining a cavity and provided with a first opening ( 60 ) that makes it possible to feed water into the cavity, a second opening that makes it possible to discharge water from the cavity, and a third opening that makes it possible to connect the cavity ( 41 ) with a chamber; a stopper ( 49 ) that is rotatable inside the cavity, the stopper comprising a depression ( 77 ) on the outer surface ( 90 ) thereof that contributes to the definition of a passage enabling the flow of water between the first and third openings in first angular positions of the stopper and moreover enabling the flow of water between the second and third openings in second angular positions of the stopper, a sealing device that makes it possible to ensure a sealed stopping of the first opening ( 60 ) by means of the stopper in said second angular positions of the stopper; and a second sealing device that makes it possible to ensure a sealed stopping of the second opening by means of a stopper in said first angular positions of the stopper. | 8 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] Not Applicable
FEDERALLY SPONSORED RESEARCH
[0002] Not Applicable
SEQUENCE LISTING OR PROGRAM
[0003] Not Applicable
BACKGROUND OF THE INVENTION
[0004] 1. Field of Invention
[0005] This invention relates to electronic sensing and monitoring devices, specifically a wireless electronic monitor of pH and the like for aquariums.
[0006] 2. Prior Art
[0007] Previously, a pH measurement of water in a container such as an aquarium was done using colorimetry, a process wherein the color of an indicator chemical mixed with the water under test is compared with a chart that approximately correlates that color with a discrete value of pH. Colorimetry by its nature does not provide an output as a sensor that can be processed by electronic circuitry, and is therefore not a suitable sensor for a monitor that provides a warning when pH levels are outside of a desired range.
[0008] A combination electrode of the type available from Omega Engineering of Stamford, Conn. generates a voltage dependent on ionic activity in the water, can be configured to measure pH, and can operate continuously immersed in the water being tested. The combination electrode requires a meter to be useful, and a basic meter configuration includes a display of the pH or other ionic activity and some method to calibrate the electrode with standard solutions.
[0009] While the use of the combination electrode is ubiquitous in science and industry, it is not common in aquarium keeping and the like. Most typical pH measurement systems available from scientific instrument suppliers have a cable or wire and have a meter that either sets upon a benchtop or is mounted in an equipment panel. A notable exception is a handheld pH tester with the electrode and the display integrated into a compact and rugged field instrument. For a container such as a tank, the combination electrode typically penetrates the wall of the tank using a bulkhead fitting or similar to make a watertight connection. The combination electrode is not always connected directly to a meter with a coaxial cable. A transducer that converts the electrode output to a modulated current source is well known as a transmitter. Additionally, the combination electrode output can be sent through ambient air using radio waves or infrared light to a remote meter using prior art. Lastly, industrial process control applications commonly use a set-point monitor to provide a warning or alarm when the pH of a process is not within specified limits.
[0010] A limitation of using a typical electrode and meter is the coaxial cable or wire connecting the two.
[0011] A limitation of the typical meter and combination electrode is that there is no convenient surface to place it near a typical aquarium, or to mount the electrode. The typical scientific or industrial pH measurement equipment is not an aesthetically pleasing addition to the natural environment that an aquarium attempts to represent.
[0012] A limitation of a handheld pH test meter is that the typical design is intended for sampling applications, and has neither an intrinsic means of attachment to a tank or a set-point alarm that would make it a true monitor.
[0013] A limitation of measuring the pH of a liquid in a tank or container in most industrial applications is the requirement to penetrate the wall so that the combination electrode has access to the interior of the tank.
[0014] A limitation of using radio waves to transmit the output of the electrode to a meter is that the antenna attached to the transmitter must be kept above the surface of the liquid within the tank if the liquid is conductive, such as saltwater. This is due to the phenomena of attenuation of an electromagnetic field in a conductive fluid.
[0015] A limitation of the typical pH measurement system configured with a set-point monitor is again the industrial nature of the typical equipment available. A pH electrode would either have to penetrate the wall of the aquarium, or would have to be mounted to the lip around the edge, similar to how many aquarium heaters are attached. It is preferable to keep the electrode and the meter below the lip of the aquarium to avoid interference with the cover of the tank.
OBJECTS AND ADVANTAGES
[0016] Accordingly, several objects and advantages of the present invention are:
1. to provide an automatic and periodic measurement of pH in a container such as an aquarium not possible with colorimetry; 2. to eliminate the use of a coaxial cable or wires between the pH sensor and the pH display; 3. to provide a small device that can be conveniently placed anywhere on any wall of an aquarium; 4. to eliminate the need to penetrate the wall of an aquarium or similar container; 5. to provide an efficient wireless transmittal of sensor output from within a salt water aquarium that cannot be blocked by objects within the aquarium; 6. to provide an alarm when the pH of an aquarium is outside of pre-determined limits; and 7. to obviate the need to personally test the water of an aquarium regularly.
[0024] Further objects and advantages are to provide a wireless pH monitor for aquariums that is simple to install and remove, provides an easy pH sensor replacement method, can be configured for remote monitoring, and can be configured for data logging of the pH sensor output. Still further objects and advantages of the present invention will become apparent from a consideration of the ensuing detailed description of the invention in conjunction with the accompanying drawings and the appended claims.
SUMMARY
[0025] In accordance with the present invention a wireless electronic monitor for pH in an aquarium comprising two devices that sandwich a wall of the aquarium, the interior device transmitting the output of a pH sensor through the wall to the exterior device using frequency modulated pulses of light.
DRAWINGS
Figures
[0026] FIG. 1 shows a wireless electronic monitor in an exploded view demonstrating how it is used to sandwich a transparent aquarium wall.
[0027] FIG. 2 a to 2 c show the components attached to the transmitter electronics housing.
[0028] FIGS. 3 a and 3 b show the connection of the pH sensor to complete the sense and transmit assembly (STA).
[0029] FIG. 4 shows the receive and display assembly (RDA) components that are attached to the receiver electronics housing.
[0030] FIG. 5 shows a schematic representation of the wireless monitor configured for measuring pH in an aquarium.
DRAWINGS
Reference Numerals
[0000]
6 pH Sensor
8 Molded Header
10 Transmitter Housing
12 Battery Cover
14 Transparent Window
15 Sense and Transmit Assembly (STA)
16 Transparent Tank Wall
18 Receiver Housing
20 pH Sensor Output Display
22 Water Test Button
24 Up Arrow Button
26 Down Arrow Button
28 Alarm Speaker
30 Alarm Light
32 Faceplate
33 Receive and Display Assembly (RDA)
34 Ring Magnet
36 Infrared Emitter
38 Infrared Detector
39 Infrared Emitter-Detector Pair
40 Electrical Socket Connector
42 Transmitter Circuit Board
44 Threaded Standoff
45 Transmitter Circuit Assembly
46 Potting Material
48 9 Volt Battery
50 Elastomer Battery Seal
52 Elastomer Washer
54 Thumbscrew
56 Elastomer Sensor Connection Seal
58 Electrical Pin Connector
60 Receiver Circuit Board
74 STA Waterproof Boundary
76 RDA Waterproof Boundary
100 Infrared Detector Power Supply
102 Electronic Switch Power Supply
104 Electronic Switch
106 Electronic Switch Input Voltage Level
108 pH Measurement Circuitry Power Supply
110 Manual pH Measurement Request
112 Central Processing Unit (CPU)
114 Single Voltage Pulse
116 Single Infrared Light Pulse
118 Automatic pH Measurement Request
120 Electronic Memory
122 Electronic Timer
124 Timer Output
126 Amplifier Circuit
128 pH Sensor Output
130 Amplifier Circuit Output
132 Floating Reference Circuit
134 Voltage Controlled Oscillator Circuit (VCO)
136 pH Modulated VCO Input Voltage
138 Train of Frequency Modulated Voltage Pulses
140 Train of Frequency Modulated Infrared Light Pulses
142 pH Modulated Frequency Signal
144 Digital pH Value
146 Increment Set-Point Signal
148 Decrement Set-Point Signal
150 Audible Alarm CPU Output
152 Visible Alarm CPU Output
DETAILED DESCRIPTION
FIGS. 1 Through 5 -Preferred Embodiment
[0092] The detailed description set forth in connection with the appended drawings is intended as a description of presently preferred embodiments of the invention and is not intended to represent the only forms in which the present invention may be constructed and/or utilized. The description sets forth the functions and the sequence of steps for constructing and operating the invention in connection with the illustrated embodiments. However, it is understood that the same or equivalent functions and sequences may be accomplished by different embodiments that are also intended to be encompassed within the scope of the invention.
[0093] A preferred embodiment of the wireless electronic monitor for a container such as an aquarium is illustrated in FIG. 1 (exploded view). The monitor is comprised of a sense and transmit assembly (STA) 15 and a receive and display assembly (RDA) 33 . The STA 15 is configured with a pH sensor 6 that is well known as a combination electrode of the type available from Omega Engineering Inc. of Stamford, Conn. However, any other device that exhibits a variable electrical output dependent upon aqueous ionic activity, dissolved gas concentration, or temperature and the like can be used as a transducer for the STA 15 .
[0094] A molded header 8 is cast around the electrical connection end of the pH sensor 6 from a two-part polyurethane or epoxy resin that cures at approximately room temperature. The resin cannot be cured at elevated temperatures or generate significant exothermic heat during the cure because the pH sensor 6 contains air and aqueous solutions that can expand or boil. The header 8 is a watertight electrical and mechanical connection of the sensor 6 to power and signal processing circuits within a transmitter housing 10 . In the preferred embodiment, the pH sensor 6 is detachable from the STA 15 so it can be easily replaced if broken or at the end of its operational life. The transmitter housing 10 and a battery cover 12 are both injection molded from a thermoplastic resin such as acrylonitrile butadiene styrene (ABS), polypropylene or the like. A transparent window 14 allows the transmission of light through an opening in the transmitter housing 10 . The STA 15 is oriented to place the transparent window 14 against the interior side of a transparent wall 16 . A similar opening (not shown) in a receiver housing 18 is aligned line-of-sight with the opening in the transmitter housing 10 . The alignment of the two openings and the location of the wireless monitor on the tank wall 16 is maintained using magnetic clamping force on the wall between the STA 15 and the RDA 33 .
[0095] As shown in FIG. 1 , the preferred embodiment of the RDA 33 is configured with a pH sensor output display 20 . A water test button 22 prolongs battery life by providing an on-demand measurement and display of pH. An up arrow button 24 and a down arrow button 26 permit set-point adjustments for the desired range of pH. If pH levels are outside of that range, an alarm speaker 28 and an alarm light 30 are activated. The RDA 33 is sealed from potential water spills during aquarium maintenance by a faceplate 32 . The receiver housing 18 and the faceplate 32 of the preferred embodiment are molded from similar thermoplastic materials used for the transmitter housing 10 and the battery cover 12 .
[0096] FIGS. 2 a to 2 c show the various components attached to the transmitter housing 10 . As shown in FIG. 2 a (exploded isometric view), the transparent window 14 is placed over the opening in the housing 10 and sealed watertight with silicone adhesive (not shown) or the like. A ring magnet 34 made of neodymium or similar high magnetic strength material of the type available from Master Magnetics, Inc. of Castle Rock, Colo. is placed on the window 14 and is mechanically attached to the housing 10 with epoxy adhesive (not shown) or the like. The housing 10 has a molded feature that assists aligning the window 14 and the magnet 34 with the opening in the housing 10 . A transmitter circuit assembly 45 is attached to the magnet 34 with epoxy adhesive or the like. The transmitter housing 10 is then laid on a horizontal surface and filled with a potting material 46 such as polyurethane or silicone rubber to seal the transmitter circuit assembly 45 .
[0097] As illustrated in FIG. 2 b (isometric view), the transmitter circuit assembly 45 is partly comprised of an infrared emitter-detector pair 39 , an electrical socket connector 40 , and a transmitter circuit board 42 . The transmitter circuit assembly 45 is configured to place the emitter-detector pair 39 within the center opening of the ring magnet 34 so that light can be emitted or detected through the transparent window 14 . An infrared emitter 36 , an infrared detector 38 , and the socket connector 40 are well known electronic components of the type available from Digi-Key Corporation of Thief River Falls, Minn. Other electronic components comprising the transmitter circuit assembly 45 are not shown for clarity. A transmitter circuit board 42 is drilled with holes to create locations to insert a threaded stand-off 44 made of stainless steel or aluminum. As shown in FIG. 2 c , the potting material 46 fills the transmitter housing 10 cavity to just below the openings in the stand-off 44 and the socket connector 40 .
[0098] Referring to FIG. 2 a , a rectangular recess is cast into the potting 46 by using a block of compliant material such as silicone rubber (not shown) to form the recess when the liquid potting 46 is dispensed or poured into the transmitter housing 10 . After the potting material 46 hardens, the rubber block is removed, and a 9 volt battery 48 is placed in the recess and connected to the transmitter assembly 45 using a well known 9 volt battery connector (not shown). The battery 48 is kept dry using an elastomer battery seal 50 and an elastomer washer 52 molded from silicone rubber or the like. By hand tightening a plastic thumbscrew 54 into the threaded stand-off 44 at each end of the battery cover 12 , the battery 48 is kept dry. The plastic thumbscrew 54 is designed to preferentially fail if over-tightened into the metal threaded stand-off 44 .
[0099] FIGS. 3 a (exploded isometric view) and 3 b (isometric view) show the connection of the pH sensor 6 with the molded header 8 to the assembly shown in FIG. 2 c . Referring to FIG. 3 a , an elastomer sensor connection seal 56 is molded from silicone rubber or the like to seal the gap between the molded header 8 and the hardened potting material 46 . An electrical pin connector 58 is partially encapsulated in the molded header 8 and inserted into the socket connector 40 openings (shown in FIG. 2 c ). By tightening a third thumbscrew 54 into a third threaded standoff 44 (shown in FIG. 2 c ), the seal 56 is compressed into the surface of the cured potting material 46 . Another washer 52 maintains a waterproof seal of the socket connector 40 and the pin connector 58 . FIG. 3 b shows the fully assembled and sealed STA 15 ready to submerge in water.
[0100] As shown in FIG. 4 (exploded isometric view), the RDA 33 also contains the transparent window 14 and the ring magnet 34 . Both are attached to a feature molded into the receiver housing 18 in a manner similar to the method used for the transmitter housing 10 . A receiver circuit board 60 is configured with the emitter-detector pair 39 (not shown) and is mechanically attached to the ring magnet 34 with epoxy or similar adhesive. Other electronic components on the receiver circuit board 60 and the battery power supply for the RDA 33 are not shown for clarity.
[0101] Additionally, the preferred embodiment integrates the water test button 22 , the up arrow button 24 , and the down arrow button 26 into a well known membrane switch (not shown) of the type available from Nelson Nameplate of Los Angeles, Calif. The membrane switch is fabricated from laminated sheets of polyester or polycarbonate, to which conductive and colored inks are applied. Switches, light emitting diodes, regions of transparency for viewing underlying displays, and artwork can be combined into a very flat structure that is rugged and has low fabrication costs. The membrane switch is attached to the faceplate 32 typically using tape backed with acrylic adhesive or the like to provide a sealed keypad that is waterproof. Electrical contact of such a membrane switch to an electrical connection on the receiver circuit board 60 is typically done with a pigtail formed in the laminated sheets (not shown).
[0102] A schematic representation of the wireless monitor of pH for an aquarium is illustrated in FIG. 5 . Clearly shown is the demarcation of the two main assemblies, with the STA 15 on the internal water side of the tank wall 16 , and the RDA 33 on the external air side. An STA waterproof boundary 74 is formed around the electronics contained within the STA 15 , leaving the water sensing end of the pH sensor 6 exposed to the water. Similarly, an RDA waterproof boundary 76 is formed around the electronics contained within the RDA 33 .
[0103] FIG. 5 shows that the battery 48 provides an infrared detector power supply 100 to the infrared detector 38 contained in the STA 15 . The battery 48 also provides an electronic switch power supply 102 to an electronic switch 104 . When the infrared detector 38 is not illuminated above a set light threshold level, an electronic switch input voltage level 106 is configured to keep the switch 104 open. The open switch 104 prevents consumption of a pH measurement circuitry power supply 108 during periods of time when a pH measurement is not desired.
[0104] When a pH measurement is desired, FIG. 5 shows two methods by which it may be requested. Using the RDA 33 , a manual pH measurement request 110 can be sent to a central processing unit (CPU) 112 by pressing the water test button 22 . The CPU 112 sends a single voltage pulse 114 to the infrared emitter 36 within the RDA 33 , causing it to emit a single infrared light pulse 116 . An automatic pH measurement request 118 uses stored times or time periods accessed from an electronic memory 120 by the CPU 112 to initiate the single light pulse 116 .
[0105] The single pulse of infrared light 116 transmits through the transparent window 14 in the RDA 33 , through the transparent wall 16 , through the transparent window 14 in the STM 15 , and illuminates the infrared detector 38 within the STA 15 . During the period that the detector 38 is illuminated by the light pulse 116 , the switch input voltage level 106 is configured to close the open switch 104 .
[0106] For the duration of the light pulse 116 , the pH measurement circuitry power supply 108 is connected to an electronic timer 122 that self-starts immediately. A timer output 124 is connected to the switch input voltage level 106 to hold the switch 104 closed after the duration of the single light pulse 116 has elapsed, and will remain closed for the duration that the timer 122 is on. While the electronic timer 122 is on, the pH measurement power supply 108 is connected to the timer 122 . When the timer 122 reaches the end of the specified on period, the timer output 124 is configured to open the switch 104 and eliminate its own power supply 108 . The timer 122 will not re-start until the single infrared light pulse 116 requests another pH measurement.
[0107] During the period that the timer 122 is on, the pH measurement circuitry power supply 108 is turned on to the rest of the circuitry on the transmitter circuit assembly 45 (shown in FIG. 2 b ). In the preferred embodiment, an amplifier circuit 126 and the pH sensor 6 of FIG. 5 are placed close together and encapsulated in the molded header 8 (shown in FIGS. 3 a and 3 b ). An amplifier circuit output 130 shown in FIG. 5 is connected to the transmitter circuit assembly 45 by the socket connector 40 (shown in FIGS. 2 a to 2 c ), and the pin connector 58 (shown in FIG. 3 a ).
[0108] Referring again to FIG. 5 , a floating reference circuit 132 places the reference potential for the pH sensor 6 and the amplifier circuit 126 at approximately 3 volts, or about one third of the 9 volt battery 48 potential. This is required because the pH sensor can be a positive or negative voltage. The gain of the amplifier 126 is configured so that negative voltage levels at the amplifier output 130 do not go more than about 2 volts below the reference potential for all expected values of pH to be measured. A voltage controlled oscillator circuit (VCO) 134 receives a pH modulated VCO input voltage 136 that will always be positive and indicative of the pH sensor output 128 . By placing the reference potential at approximately 3 volts and limiting the amplifier output 130 to about plus or minus 2 volts relative to that reference, the battery 48 can be used when depleted to as low as 5 volts.
[0109] The VCO 134 converts the pH dependent VCO input voltage 136 into a train of frequency modulated voltage pulses 138 . The voltage pulses 138 drive the infrared emitter 36 in the STA 15 to emit a train of frequency modulated light pulses 140 . The light pulses 140 are transmitted through the transparent window 14 in the STA 15 , the transparent tank wall 16 , and the transparent window 14 in the RDA 33 . The infrared detector 38 in the RDA 33 is illuminated by the train of light pulses 140 and generates a pH modulated frequency signal 142 that is sent to the CPU 112 . The frequency of the signal 142 is compared with a calibration look-up table in the electronic memory 120 that is obtained by measuring the frequency of the pH modulated signal 142 when the pH sensor 6 is immersed into a standard solution of known pH for two or more pH values. A digital pH value 144 of the current pH within the tank is sent to the pH sensor output display 20 and provides a visible numeric pH value.
[0110] By using the up arrow button 24 and the down arrow button 26 to adjust upper and lower bounds for acceptable pH, set-point values are stored in the electronic memory 120 . The ability to send an increment set-point signal 146 or a decrement set-point signal 148 to the CPU 112 permits adjustable alarm levels for aquarium pH. The CPU 112 is programmed to periodically make an automatic pH measurement request 118 and initiate a pH measurement in the manner shown in FIG. 5 . The pH modulated frequency signal 142 obtained from the periodic measurement is evaluated by the CPU 112 programming to ascertain whether the pH of the water contained in the tank is outside of two limit values stored in electronic memory 120 . If the pH is outside of the pre-defined limits, an audible alarm CPU output 150 will activate the alarm speaker 28 . A versatile alarm system includes a visible alarm CPU output 152 to activate the alarm light 30 when an aquarium owned by a hearing impaired person requires attention.
Operation—FIGS. 1, 2 , and 5
[0111] The manner of using the wireless monitor is to immerse the STA 15 into the aquarium water and place the side with the transparent window 14 against the transparent wall 16 of the tank. Holding the STA 15 against the interior surface of the wall 16 with one hand, the transparent window 14 in the RDA 33 is placed against the exterior surface of the wall 16 using the other hand. Sliding the RDA 33 or the STA 15 against their respective surfaces of the wall 16 , the two windows 14 are brought into approximate line-of-sight alignment until the magnet 34 in each attract one another. When the magnetic attraction between the STA 15 and the RDA 33 is sufficient to hold them in place on the tank wall 16 , they are released and rely on friction to maintain their position. When the wall 16 is sandwiched between the STA 15 and the RDA 33 , the position of this invention can be adjusted as desired by grasping the RDA 33 and sliding it on the exterior surface of the wall 16 . Held in place by magnetic attraction, the STA 15 will slide along the interior surface of the tank wall 16 and follow the movement to the desired wall 16 location for the wireless monitor. This makes it a simple process to sandwich the wall 16 with the STA 15 and the RDA 33 near the surface of the water and move it to a deeper location on the transparent wall 16 .
[0112] To make a pH measurement, the water test button 22 is manually pushed. The RDA 33 will send a single light pulse 116 to the STA 15 that will activate the timer 122 and turn the pH measurement circuit power supply 108 on for a pre-determined amount of time. For that period of time, a train of frequency modulated infrared light pulses 140 are transmitted from the STA 15 to the RDA 33 . The CPU 112 will sample the pH modulated frequency signal 142 for the time required to obtain an accurate average of its frequency. That frequency is converted to a digital pH value 144 that is then shown in the monitor display 20 as a numerical value of pH for a pre-determined amount of time.
[0113] To calibrate the pH sensor 6 or to adjust alarm set-points, there are numerous ways to indicate to the CPU 112 that such an action is desired. Simultaneously pressing the up arrow button 24 and the down arrow button 26 , or the addition of specific buttons to the faceplate 32 are only two ways that can be employed. The specific mechanism by which the look-up table in electronic memory 120 that contains calibration constants and set-point pH values is updated is beyond the scope of the present invention. Because this invention is clearly described as dependent upon the CPU 112 and the electronic memory 120 , the reader can see that the specificities of software programming are not necessary to provide full disclosure.
Additional Embodiments
[0114] There are a number of water parameters that can be sensed using a probe similar to the pH sensor of this invention. Ions that are of interest to aquarium owners are reflected in the commercial availability of colorimetry kits that test for ammonia, nitrate, nitrite, hardness and alkalinity. All of the ions measured by the colorimetry kit can be measured by similar electrodes used to measure pH, and thus can be directly used by the wireless monitor. Dissolved oxygen sensors, conductivity cells for salinity, and temperature sensors such as a thermistor are also readily adapted to the wireless monitor for aquariums.
[0115] The preferred embodiment of this invention describes a single sensor, specifically for measuring pH. In practice, this invention can be embodied with multiple sensors. A second device such as a temperature sensor can easily be attached to the described transmitter circuit assembly and provide monitoring of yet another important water parameter for aquariums and the like.
[0116] The wireless monitor can be configured with a sensor for a fluid such as a gas, enabling this invention to be used to measure moisture, flammable or explosive gas levels, and oxygen in a closed container such as a glove-box.
[0117] Configured with a radiation sensor, this invention can be used for radioactive applications where the wireless monitor can be placed on a glove-box viewing window or the leaded glass of a radioactive waste storage chamber.
[0118] This invention as described is used on an aquarium having a transparent wall of glass, acrylic or the like. In the case of an opaque tank made of a material such as fiber-filled polypropylene or polyethylene, the infrared light used to convey the sensor information would not transmit through the wall. In such a case, this invention would be useful using another form of energy to transmit the pulses that initiate of a pH measurement and subsequent pH sensor output. Such forms of energy include, but are not limited to:
1. a fluctuating magnetic field for a tank wall material that does not form a Guassian shield, such as a fiber-filled thermoplastic or thermoset polymer, copper, and some stainless steels; 2. radio or microwave frequency radiation for a non-metallic tank wall where the conductivity of the liquid within does not significantly affect the signal strength; and 3. acoustic energy to transmit the sensor output through tank walls made of a material that interposes a Gaussian shield between the STA and the RDA.
[0122] The method by which this invention can be attached to the tank wall and maintain the location in which it was placed is shown to be the mutual attraction of two magnets in the preferred embodiment. This method works best when the wall thickness is less than approximately one half inch. For a wall that is significantly thicker, this invention is useful if the STA and the RDA are attached directly to the wall using a suction cup or similar device. In applications where there are large fish that could knock the STA off from the interior wall or other turbulent scenarios, it can be attached directly to the tank wall using an adhesive such as silicone or epoxy. When using the monitor in public places, permanent attachment of the RDA to the exterior wall of the tank may be required to prevent theft.
[0123] The present invention can be used on a container such as a bag made of polyethylene, polyethylene terephthalate (PET), or similar material.
[0124] The encapsulation with the potting material of the transmitter circuit assembly can be obviated using housing structures that incorporate rubber seals and the like.
[0125] The frequency modulated voltage pulses and subsequent frequency modulated light pulses can be configured in pattern conforming to a standard serial communication format such as RS-232 or similar.
[0126] The detachable sensor shown in the preferred embodiment can be incorporated directly into the STA if the operational life is considered permanent, such as a thermocouple, thermistor, or conductivity cell and the like.
[0127] This invention finds great usefulness when configured with access to the Internet or a wireless cellular phone network to send the measurement results of many tanks to a central monitoring location.
[0128] By storing the measurement results in electronic memory for later retrieval, this invention is useful in applications such as shipment of live aquatic specimens and other records of water fitness over time.
[0129] This invention can be configured in many shapes other than rectangular, including but not limited to circular, square, triangular, or an iconic shape such as an aquatic life form, logo or decorative representation.
Advantages
[0130] From the description above, a number of advantages of this wireless electronic monitor for containers such as aquariums become evident:
1. An aquarium can be monitored around the clock for pH. 2. This invention generates an audible and visible alert if the pH of the water is outside of expected boundaries. 3. This invention is easy to install on the wall of a tank near the surface the water and can be moved to a deeper location without inserting the hand or arm into the water. 4. A pH dependent electrical signal gives the opportunity to use a CPU to manage sensor calibration, activate alarms, and store measurement results. 5. The wireless electronic monitor has a broader test range and finer resolution of measurement than colorimetry pH measurements. 6. This invention is simple to use and less intrusive for aquarium applications than laboratory and industrial pH monitoring equipment presently available. 7. Sandwiching the wall of a container such as a tank or aquarium permits this invention to operate in saltwater because the transmission medium is the wall material, not the liquid contained in the tank.
CONCLUSIONS, RAMIFICATIONS, AND SCOPE
[0138] Accordingly, the reader will see that the wireless electronic monitor can be configured with a sensor other than for pH, can use two or more sensors together such as pH and temperature, and can be configured with a sensor for gases, vapors or radioactivity. Also, this invention can use forms of energy other than light to communicate sensor output, can also be attached to a container wall with suction generating devices or adhesive, can be configured with access to distributed communications-networks to monitor multiple tanks from a remote location, and can be configured to store periodic measurement results in the electronic memory to serve as a data logger. Additional embodiments use modulated light pulses that conform to a serial communication standard, integrate the sensor into the sense and transmit assembly (STA), and can have various shapes.
[0139] Although the description above contains many specificities, these should not be construed as limiting the scope of the invention but as merely providing illustrations of some of the presently preferred embodiments of this invention. While the invention has been described in connection with certain preferred embodiments, it is not intended to limit the scope of the invention to the particular forms set forth, but on the contrary, it is intended to cover such alternatives, modifications, and equivalents as may be included within the scope of the invention as defined by the claims. | A wireless electronic monitor for a container such as an aquarium is described. The apparatus comprises a sense and transmit assembly (STA) 15 configured with a pH sensor 6 submerged in the water inside the aquarium, and a receive and display assembly (RDA) 33 that displays the output of the sensor 6 . A line-of-sight orientation is maintained between openings in each assembly using magnets to generate a clamping force on a transparent tank wall 16 . A water test button 22 is pressed, and a single pulse of light travels from the RDA 33 to the STA 15 . The single pulse of light turns the STA 15 on by closing a timed switch to the battery power. The pH sensor 6 output is converted to a train of frequency-modulated pulses of light that are transmitted back to the RDA 33 . The frequency of the train of light pulses is determined by a CPU in the RDA 33 , and assigned a pH value from calibration tables stored in electronic memory. The pH value is shown on a pH sensor output display 20 which can be manually placed anywhere on the tank wall by grasping the RDA 33 from the outside of the aquarium, and sliding the entire monitor to its desired location without getting wet hands. To fully realize a true monitor of the pH, the CPU in the RDA 33 is programmed to make periodic measurements of the pH by periodically emitting the single pulse of light to the STA 15 . The results of each measurement are compared with upper and lower pH boundaries stored in an electronic memory. If a measurement is outside of a pre-determined range, the CPU activates an alarm speaker 28 and an alarm light 30. | 0 |
FIELD OF THE INVENTION
The present invention relates to a hydrogen occluding alloy exhibiting significantly high hydrogen absorption and desorption rates, and excellent initial activation characteristics in pratical use for electrodes of batteries, for example.
BACKGROUND OF THE INVENTION
Hitherto, a variety of hydrogen occluding alloys have been proposed, and a hydrogen occluding alloy which is disclosed on page 369 of the abstract of "The 35th Battery Symposium of Japan" held in November, 1994, in Nagoya-shi, has particularly attracted attention to battery electrodes.
The hydrogen occluding alloy is a Ni-based alloy having a reduced composition comprising, by wt % (hereinafter "%" indicates "wt %"),
33.2% of rare earth elements essentially consisting of La and/or Ce,
9.8% of Co, 1.9% of Al,
5.2% of Mn, and
the balance being Ni and unavoidable impurities; and having a single phase CaCu 5 -type crystal structure.
Hydrogen occluding alloy is typically made by preparing a molten alloy having a given composition and casting it into an ingot. When putting it to practical use as a battery electrode, for example, the ingot is subjected to temper annealing in a vacuum or nonoxidizing inert gas atmosphere at a given temperature between 900 and 1,050° C. for a given time period, if necessary, and the as-cast or temper-annealed ingot is mechanically pulverized to a predetermined particle size or pulverized by a hydrogenation process under a pressurized hydrogen atmosphere which includes hydrogen absorption at a given hot temperature between 10 and 200° C. and hydrogen desorption by vacuum evacuation.
In addition, when the hydrogen occluding alloy is applied to, for example, a battery electrode, the battery can serve a practical use after an initial activation treatment in a pressurized hydrogen atmosphere for a given time period until the electrode including the hydrogen occluding alloy has a sufficient discharge capacity at an initial stage of use.
OBJECTS OF THE INVENTION
On the other hand, there recently have been large requirements, such as larger output, higher performance, and energy saving, for batteries and heat pumps in which the hydrogen occluding alloy is widely applied. Therefore, the hydrogen occluding alloy has been required to have higher hydrogen absorption and desorption rates and a shorter initial activation time than those of the foregoing conventional hydrogen occluding alloy.
SUMMARY OF THE INVENTION
In viewpoint of the above, the present inventors have studied to improve the hydrogen absorption and desorption rates and initial activation of the hydrogen occluding alloy comprising the Ni-based alloy set forth above. As a result, the following conclusion was obtained: When the conventional hydrogen occluding alloy of the as-cast or temper-annealed ingot set forth above is modified by being subjected to a treatment in which it is held in a hydrogen atmosphere of a pressure in the range of from 1 to 2 atms (atmospheres), preferably 1 to 1.2 atms, preferably for a period of time in the range of from 0.25 hours to 5 hours, then heated to a temperature in the range of from 600 to 950° C., preferably 700 to 900° C. and then cooled, the resulting alloy has a novel microstructure in which fine rare earth element hydride is dispersively distributed in a CaCu 5 -type crystal matrix. In this treatment, the alloy is preferably held in the 600 to 950° C. atmosphere for a time period of at least 0.5 hour, preferably about 1 hour. In this treatment, the hydrogen atmosphere is preferably maintained during the heat treatment in the range of from 600 to 950° C. and the hydrogen atmosphere is preferably also maintained at least until the alloy is cooled down to 300° C. or less. As discussed herein, the "ratio of the rare earth element hydride" refers to the percentage of the area of the alloy (or a section or surface of the alloy) occupied by rare earth element hydride as viewed two-dimensionally (e.g., by microscopy or diffractometry). When the ratio of the rare earth element hydride is 0.5 to 20% by area, preferably 0.5 to 10% by area, the alloy exhibits catalytic effects to remarkably promote hydrogen absorption and desorption without discharge capacity deterioration. Therefore, the alloy can absorb and desorb hydrogen atoms at rates higher than those of the conventional hydrogen occluding alloy, and initial activation is significantly promoted.
The present invention was achieved based on the results set forth above, and is characterized by a hydrogen occluding alloy having a composition comprising, by wt %,
32 to 38% of rare earth elements,
0.5 to 3.5% of Al,
0.5 to 10% of Mn,
0.005 to 0.5% of hydrogen, and
the balance being Ni and unavoidable impurities;
wherein said alloy has a microstructure characterized in that fine rare earth element hydride is dispersively distributed in a matrix having a CaCu 5 -type crystal structure in a ratio of 0.5 to 20% by area. The aforementioned rare earth elements preferably comprise La and/or Ce, optionally together with other rare earth elements including Pr and Nd. This alloy may optionally further contain Co in an amount in the range of from 0.1 to 17 wt %.
In a preferred aspect of the present invention, there is provided a hydrogen occluding alloy having a composition comprising, by wt %,
32 to 38% of rare earth elements,
0.1 to 17% of Co,
0.5 to 3.5% of Al,
0.5 to 10% of Mn,
0.005 to 0.5% of hydrogen, and
the balance being Ni and unavoidable impurities;
wherein said alloy has a microstructure characterized in that fine rare earth element hydride is dispersively distributed in a matrix having a CaCu 5 -type crystal structure in a ratio of 0.5 to 20% by area. The aforementioned rare earth elements preferably comprise La and/or Ce, optionally together with other rare earth elements including Pr and Nd.
In a further preferred aspect of the present invention, there is provided a hydrogen occluding alloy having a composition comprising, by wt %,
32 to 35% of rare earth elements,
0.5 to 3.5% of Al,
0.5 to 10% of Mn,
0.005 to 0.2% of hydrogen, and
the balance being Ni and unavoidable impurities;
wherein said alloy has a microstructure characterized in that fine rare earth element hydride is dispersively distributed in a matrix having a CaCu 5 -type crystal structure in a ratio of 0.5 to 10% by area. The aforementioned rare earth elements preferably comprise La and/or Ce, optionally together with other rare earth elements including Pr and Nd.
In a further preferred aspect of the present invention, there is provided a hydrogen occluding alloy having a composition comprising, by wt %,
32 to 35% of rare earth elements,
4 to 17% of Co,
0.5 to 3.5% of Al, 0.5 to 10% of Mn,
0.005 to 0.2% of hydrogen, and
the balance being Ni and unavoidable impurities;
wherein said alloy has a microstructure characterized in that fine rare earth element hydride is dispersively distributed in a matrix having a CaCu 5 -type crystal structure in a ratio of 0.5 to 10% by area. The aforementioned rare earth elements preferably comprise La and/or Ce, optionally together with other rare earth elements including Pr and Nd.
In addition, there is provided a method comprising:
melting raw materials in weight percentages substantially corresponding to the weight percentages in the alloys of the present invention as discussed above, thereby forming an alloy;
casting the molten metal, thereby forming an ingot;
(optionally) temper-annealing the alloy by heating the alloy to a temperature of from about 850 to 1050° C. (referred to herein as a "temper-annealing" step);
then subjecting the alloy to a hydrogen atmosphere of a pressure in the range of from 1 to 2 atms (atmospheres), preferably 1 to 1.2 atms, and a temperature in the range of from about 0 to 100° C. (referred to herein as the "holding step");
then heating the alloy to a temperature in the range of from 600 to 950° C., preferably 700 to 900° C., (referred to herein as the "heating step");
and then cooling the alloy (referred to herein as the "cooling step"), thereby providing an alloy having a novel microstructure in which fine rare earth element hydride is dispersively distributed in a CaCu 5 -type crystal matrix, with rare earth element at the Ca sites, and e.g., Ni, Co, Al, and Mn at the Cu sites.
Said CaCu 5 -type crystal structure (or AB 5 ) is well known in the art, and refers to a crystal structure having the configuration depicted in FIG. 2. In this structure, the atomic arrangement consists of an alternate stacking along the c-axis of two different layers. The layer at z=0 is close-packed and contains one A and two B atoms per unit cell. The layer at z=1/2, is close-packed with a quarter of the atoms missing, leaving three B atoms per unit cell. It is stacked relative to the layer at z=0 in such a way that the vacancies are centered on the nearest-neighbor A--A connecting lines. Thus, the A atoms are surrounded by six B atoms in each of the layers at z=0 and z=±1/2, giving a total coordination number for A by B of 18. The crystal structure is described in space group P6/mmm with the atomic positions: A on 1a, viz. (0,0,0), B 1 on 2c (1/3, 2/3, 0), (2/3, 1/3, 0) and B 11 on 3 g, viz. (1/2, 0, 1/2), (0, 1/2, 1/2), (1/2, 1/2, 1/2)(F. A. Kuijpers, Philips Res. Repts. Suppl. 1973, No. 2, p. 50).
As discussed above, in the "heating step", the alloy is preferably held in the 600 to 950° C. atmosphere for a time period of at least 0.5 hour, preferably about one hour. During this "heating step", the hydrogen atmosphere (in the range of from 1 to 2 atms) is preferably maintained. Also, the hydrogen atmosphere is preferably also maintained during the "cooling step" at least until the alloy is cooled down to 300° C. or less.
The composition of the hydrogen occluding alloy and the percentage of the rare earth element hydride according to the present invention are limited to the foregoing ranges in view of reasons which will now be described.
(a) Rare earth metal(s)
The rare earth element(s) form a matrix of a CaCu 5 -type crystal structure exhibiting hydrogen occlusion effects together with Ni, and form rare earth element occlusion effects together with Ni, and form rare earth element hydride which contributes to increased hydrogen charge and discharge rates and improved initial activation. Since discharge capacity decreases when the content is less than 32% or over 38%, the content is determined to 32 to 38%, preferably 32 to 35% and more preferably 33 to 34%. Another preferred range is 33 to 35%. The rare earth metal(s) preferably comprise La and/or Ce.
(b) Co
The (optional) Co component is dissolved into a matrix and has effects which reduce volume expansion/shrinkage during hydrogen absorption/desorption, prevent pulverization of the alloy and prolong its usable life. When the Co content is less than 0.1%, these desired effects cannot be achieved. Whereas, when the content exceeds 17%, the discharge capacity and initial activation effects tend to decrease. Accordingly, where Co is employed, the content is determined to 0.1 to 17%, preferably 4 to 17% and more preferably 6 to 12%.
(c) Al
The Al component is dissolved into the matrix and improves the corrosion resistance of the alloy. When the content is less than 0.5%, the desired corrosion resistance effects cannot be achieved. On the other hand, when the content exceeds 3.5%, the discharge capacity decreases. Therefore, the content is determined to 0.5 to 3.5%, and preferably 1 to 2%.
(d) Mn
The Mn component is dissolved into the matrix, decreases the equilibrium pressure for dissociating hydrogen, and contributes to increasing discharge capacity. When the content is less than 0.5%, a desired increase in discharge capacity cannot be achieved, whereas a content over 10% tends to decrease discharge capacity. Thus, the content is determined to 0.5 to 10%, and preferably 1 to 4.5%.
(e) Hydrogen and Rare Earth Element Hydride
Hydrogen predominantly bonds to rare earth elements by thermal hydrogenation at a high temperature to form rare earth element hydride which contributes to hydrogen absorption and desorption rates and improved initial activation. When the content is less than 0.005%, the ratio of the rare earth element hydride is less than 0.5% by area, and thus the desired effects cannot be achieved. Whereas a content exceeding 0.5% forms a rare earth element hydride at a ratio over 20% by area and thus drastically decreases discharge capacity. Therefore, the content is determined to 0.005 to 0.5%, preferably 0.005 to 0.2%, more preferably 0.01 to 0.2% and most preferably 0.01 to 0.08 so that the resulting ratio of rare earth element hydride finely distributed in the matrix is 0.5 to 20% by area, preferably 0.5 to 10% by area, more preferably 0.7 to 9% by area and most preferably 0.7 to 4% by area.
(f) Temper-annealing step (850° C. to 1050° C.)
The hydrogen occluding alloy of the present invention is (optionally) treated with a temper-annealing step after casting. If the temper-annealing temperature is less than 850° C., the desired homogenization of the alloy is not achieved. On the other hand, if the temper-annealing temperature exceeds 1050° C., the contents of the alloy may change because of vaporization of elements (e.g., Mn) in the alloy. Therefore, the temper-annealing temperature is determined to 850° C. to 1050° C. The temper-annealing step is preferably conducted for at least 1 hour, preferably about 10 hours.
(g) Holding step (0° C. to 100° C.)
Though it is preferable for said holding step to be conducted at room temperature, similar effects can be achieved at temperatures as low as 0° C. If the temperature during this step exceeds 100° C., the alloy does not occlude enough hydrogen so that a reaction of hydrogen and the alloy is not sufficiently even and/or uniform. Therefore, the temperature during this step is determined to 0° C. to 100° C., preferably 20° C. to 60° C.
(h) Heating step (600° C. to 950° C.)
The hydrogen occluding alloy of the present invention is heated after said holding step. If the heating temperature during this step is less than 600° C., a reaction for generating rare earth element hydride does not occur sufficiently. On the other hand, if the heating temperature exceeds 950° C., the desired microstructure is not achieved because of decomposition of rare earth element hydride. Therefore, the heating temperature during this step is determined to 600° C. to 950° C. preferably 700° C. to 900° C.
BRIEF DESCRIPTION OF THE DRAWING FIGURES
FIG. 1 is a schematic view illustrating the apparatus used for measuring hydrogen absorption and desorption rates of the hydrogen occluding alloy; and
FIG. 2 is a model of a CaCu 5 -type crystal structure.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
The hydrogen occluding alloy in accordance with the present invention will now be described in further detail with reference to an embodiment.
In an ordinary high-frequency induction melting furnace, Ni, La, Ce, Co, Al and Mn, as well as mischmetal, as raw materials, each having a purity not less than 99.9% were melted in a vacuum to prepare a Ni-based molten alloy having a given composition and casted into a water-cooled copper casting mold to form an ingot. The ingot was temper-annealed at a predetermined temperature within the range from 850° C. to 1,050° C. for 10 hours. After the ingot was maintained at room temperature (about 20° C.) for one hour in a hydrogen atmosphere of a given pressure within a range from 1 to 2 atms, preferably 1 to 1.2 atms, it was heated to a predetermined temperature within a range from 600 to 950° C., preferably 700 to 900° C., held at the predetermined temperature for 1 hour, and cooled to a temperature of 300° C. or less so that hydrogenation heat treatment was achieved. Hydrogen occluding alloys 1 through 47 in accordance with the present invention (hereinafter referred to as alloy(s) of the present invention) each having a composition set forth in Tables 1 through 4 and comprising powder of a particle size of 200 mesh or less were prepared in such a way. Concerning alloys 1-37, the "holding step" temperature is at room temperature (about 20° C.) and the hydrogen atmosphere is at a pressure in the range of about 1 to 1.2 atms. For alloys 38-47, Table 4 lists, in the far left column, the temperature and pressure at which the "holding step" according to the present invention was conducted.
For comparison, a conventional hydrogen occluding alloy (hereinafter called "a conventional alloy") having a composition shown in Table 4 was prepared under the same conditions as those for the alloys of the present invention, except that the hydrogenation treatment (i.e, the "holding step", the "heating step" and the "cooling step") after temper-annealing was omitted. Optionally, the alloy could be subjected to hydrogenation pulverization involving hydrogen absorption under conditions of a heating temperature of 200° C. and a holding time of 1 hour and a hydrogen atmospheric pressure of 8 atms. in a pressure vessel and hydrogen desorption by vacuum evacuation, so that the alloy has a particle size of 200 mesh or less. Such a pulverization step would not significantly affect the reported data concering the alloy.
Microstructures of the resulting hydrogen occluding alloys were observed by scanning electron microscopy at a magnification of 50,000, transmission electron microscopy at a magnification of 50,000, transmission electron microscopy at a magnification of 50,000 and powder X-ray diffractometry. The alloys 1 through 47 of the present invention have a structure in which fine rare earth element hydride is dispersively distributed in a matrix of a CaCu 5 -type crystal structure. The observed ratios (percent by area) of the rare earth element hydride are shown in Tables 1 through 4. Also, X-ray diffraction patterns confirmed that the matrix had a CaCu 5 -type crystal structure and the compound dispersively distributed in the matrix comprises rare earth element hydride. The conventional alloy had a single phase CaCu 5 -type crystal structure.
Then, the hydrogen absorption rate and the hydrogen desorption rate of each of alloys 1 through 47 of the present invention and the conventional alloy were measured according to JIS H7202 "Method for Measuring Hydrogenation Rate of Hydrogen Occluding Alloy" as follows:
Regarding the hydrogen absorption rate, as set forth in a schematic view in FIG. 1;
(a) Alloy powder was enclosed in a container 41 which was immersed in an oil or water bath 42, then a valve Vb was closed and valves Va and Vc were opened while maintaining the bath temperature at 200° C. to introduce pressurized hydrogen into the system from a hydrogen cylinder 43. When the pressure in the system reached 30 atms, the valve Va was closed, followed by allowing the system to stand until the pressure in the system decreased to a predetermined level (until the absorption of hydrogen by means of the alloy powder was completed). Thus, the powder was initially activated;
(b) When the pressure in the system decreased to a predetermined level of around 20 atms, the valve Vb was opened, followed by lowering the pressure in the system to 10 -2 Torr by a vacuum pump 44. Then, the bath temperature was lowered to 20° C., and the valves Vb and Vc were closed and the valve Va was opened to introduce hydrogen into the system, except for the container. When the pressure was raised to 30 atms, the valve Va was closed and the valve Vc was opened. In such a state, the pressure drop in the system with respect to time was measured. The amount of occluded hydrogen at the point when the amount of hydrogen occluded by powder reached 80%, and the time taken to the foregoing moment are obtained from the pressure-drop curve so that the equation: (amount of occluded hydrogen when occlusion of 80% is realized)/(time taken to realize occlusion of 80%) was calculated. The thus-obtained value was defined as hydrogen absorption rate.
The hydrogen desorption rate was determined by the following procedure: The bath was maintained at a temperature of, for example, 120°, suitable for hydrogen desorption within a range of from 100 to 300° C., in the state in which measurement of the hydrogen absorption rate had been completed, that is, in the state in which the valves Va and Vb were closed, the valve Vc was opened and the pressure in the system reached a predetermined level of around 20 atms. After the valve Vb was opened and the valve Vc was closed to evacuate the system, except for the container 41, to 10 -2 Torr, the valve Vb was closed and the valve Vc was opened. In such a state, the rise in pressure of the system with respect to time was measured. The amount of desorbed hydrogen at the point when the amount of hydrogen desorbed from powder reached 80%, and time taken to the foregoing moment are obtained from the pressure-rise curve so that the equation: (amount of desorbed hydrogen when desorption of 80% is realized)/(time taken to realize desorption of 80%) was calculated. The thus-obtained value was defined as hydrogen desorption rate. The results are shown in Tables 5 and 6.
For the purpose of evaluating the initial activation of alloys 1 through 47 of the present invention and the conventional alloy, each alloy was used as an active material for negative electrode of a battery, and the battery was subjected to repeated charge/discharge cycles until the battery showed a maximum discharge capacity as shown below in detail. The inital activation was taken as the number of charge/discharge cycles at which the discharge capacity corresponds to 97% of the maximum discharge capacity.
Cuprous oxide (Cu 2 O) as a conductive agent, polytetrafluoroethylene (PTFE) as a binder and carboxymethyl cellulose (CMC) as a thickener were added to each of alloys 1 through 47 of the present invention and the conventional alloy, and the resulting paste was loaded on a commercially available foamed nickel plate having a porosity of 95%. The foamed nickel plate was dried, pressed, and shaped into a cut plate of 30 mm by 40 mm having a thickness of 0.40 to 0.43 mm. The amount of loaded active material was approximately 1.8 g. A nickel thin plate as a lead was welded to a side of the cut plate to form a negative electrode. On the other hand, a positive electrode was formed by preparing a paste from Ni(OH) 2 as an active material, a cobalt monoxide (CoO) as a conductive agent, polytetrafluoroethylene (PTFE) as a binder and caboxymethyl cellulose (CMC) as a thickener; loading the paste on the foamed nickel plate; drying, pressing and shaping the foamed nickel plate into a cut plate of 30 mm by 40 mm having a thickness of 0.71 to 0.73 mm; and welding the nickel thin plate to a side of the cut plate. The positive electrodes were provided on both sides of the negative electrode through separators made of a polypropylene/polyethylene copolymer, and protection plates made of polyvinyl chloride were integrated therewith at both sides of the positive electrodes so as to support the positive electrodes. A battery was fabricated by inserting the integrated electrodes into a cell made of polyvinyl chloride and pouring a 28% aqueous KOH solution as an eelctrolyte solution into the cell.
The resulting battery was subjected to charge/discharge cycles under conditions of a charging rate of 0.25 C, discharging rate of 0.25 C, and an amount of charged electric variable corresponding to 135% of the negative electrode capacity. The charge/discharge cycles were repeated until the battery showed a maximum discharge capacity, where one charge and discharge cycle is counted as one charge/discharge.
Tables 5 and 6 show the maximum discharge capacity obtained by the procedure set forth above, as well as the number of charge/discharge cycles as a measure evaluating the initial activation, at which the discharge capacity is 97% of the maximum discharge capacity.
Results set forth in Tables 1 through 6 evidently demonstrate that each of alloys 1 through 47 of the present invention exhibits a similar discharge capacity to the conventional alloy and a microstructure in which fine rare earth element hydride is dispersively distributed in a matrix having a CaCu 5 -type crystal structure, the hydrogen absorption and desorption rates are extremely high and initial activation is significantly promoted by the effect of the rare earth element hydride, compared to the conventional alloy comprising a single phase CaCu 5 -type crystal structure which exhibits relatively low hydrogen absorption and desorption rates and delayed initial activation, due to non-existence of rare earth element hydride.
As described above, since the hydrogen occluding alloy in accordance with the present invention exhibits significantly high hydrogen absorption and desorption rates, and excellent initial activity in practical use, it significantly contributes to the achievement of high output, high performance, and energy saving in various mechanical apparatuses using the hydrogen occluding alloy.
TABLE 1__________________________________________________________________________ Rare earth Composition (% by weight) element Rare earth element Ni+ hydrideKind La Ce Pr Nd Co Al Mn Hydrogen Impurities (area %)__________________________________________________________________________Alloys of1 27.6 0.90 1.31 2.24 6.85 0.53 3.73 0.005 Balance 0.52the 2 28.6 0.93 1.36 2.32 6.88 1.26 3.85 0.056 Balance 2.89present3 29.8 0.97 1.42 2.42 6.91 1.30 3.77 0.189 Balance 8.09invention4 28.6 0.93 1.36 2.32 4.14 1.36 3.84 0.050 Balance 2.665 28.4 0.83 1.46 2.59 8.36 1.20 3.80 0.062 Balance 3.116 28.5 0.90 1.40 2.43 11.23 1.34 3.85 0.056 Balance 2.877 28.5 0.93 1.36 2.32 14.22 1.19 3.79 0.048 Balance 2.588 28.3 0.83 1.46 2.58 16.98 1.15 3.76 0.058 Balance 2.969 28.4 0.89 1.39 2.42 6.91 0.51 3.77 0.076 Balance 3.6710 28.8 0.94 1.37 2.34 6.87 2.13 3.85 0.042 Balance 2.35__________________________________________________________________________
TABLE 2__________________________________________________________________________ Rare earth Composition (% by weight) element Rare earth element Ni+ hydrideKind La Ce Pr Nd Co Al Mn Hydrogen Impurities (area %)__________________________________________________________________________Alloys of11 28.5 0.84 1.47 2.61 6.89 3.48 3.53 0.008 Balance 0.92the 12 28.7 0.90 1.40 2.44 6.93 1.21 0.52 0.085 Balance 4.03present13 28.7 0.93 1.36 2.33 6.92 1.35 1.95 0.065 Balance 3.25invention14 28.4 0.83 1.46 2.60 6.85 1.33 6.14 0.060 Balance 3.0515 28.3 0.89 1.39 2.41 6.86 1.19 7.90 0.030 Balance 1.8616 28.4 0.92 1.35 2.31 6.91 1.16 9.97 0.027 Balance 1.7717 28.6 0.93 1.36 2.32 9.73 1.85 5.30 0.030 Balance 1.8718 23.4 6.88 0.63 2.50 6.93 1.17 3.84 0.073 Balance 3.5719 17.9 9.34 1.84 4.31 6.93 1.31 3.87 0.060 Balance 3.0720 10.0 16.1 1.47 5.81 6.88 1.20 3.83 0.058 Balance 2.9821 7.9 20.9 1.77 7.17 0.12 1.18 3.79 0.441 Balance 17.9422 7.3 19.3 1.64 6.63 1.80 1.25 3.82 0.198 Balance 8.42__________________________________________________________________________
TABLE 3__________________________________________________________________________ Rare earth Composition (% by weight) element Rare earth element Ni+ hydrideKind La Ce Pr Nd Co Al Mn Hydrogen Impurities (area %)__________________________________________________________________________Alloys of23 27.4 1.12 1.28 2.28 -- 0.54 3.69 0.005 Balance 0.53the 24 28.7 0.93 1.37 2.33 -- 1.31 3.79 0.068 Balance 3.34present25 29.7 0.97 1.41 2.41 -- 1.28 3.81 0.178 Balance 7.65invention26 30.7 1.26 1.44 2.55 -- 1.29 3.77 0.309 Balance 12.8227 32.4 1.33 1.52 2.69 -- 1.24 3.64 0.466 Balance 18.9128 28.3 0.89 1.39 2.41 -- 0.52 3.78 0.064 Balance 3.1929 28.7 0.93 1.37 2.32 -- 2.34 3.67 0.030 Balance 1.8630 29.5 0.86 1.52 2.70 -- 3.46 3.41 0.107 Balance 4.9031 28.8 0.90 1.41 2.45 -- 1.18 0.51 0.095 Balance 4.4232 28.5 0.93 1.36 2.32 -- 1.30 2.15 0.049 Balance 2.61__________________________________________________________________________
TABLE 4__________________________________________________________________________ Rare earth Composition (% by weight) element Rare earth element Ni+ hydrideKind La Ce Pr Nd Co Al Mn Hydrogen Impurities (area %)__________________________________________________________________________Alloys of the 33 27.1 1.57 1.90 2.81 -- 1.32 5.86 0.065 Balance 3.26present 34 28.7 1.17 1.34 2.38 -- 1.25 8.11 0.081 Balance 3.86invention 35 29.6 0.96 1.41 2.41 -- 1.10 9.98 0.160 Balance 6.96 36 17.2 10.12 2.24 3.92 -- 1.25 3.66 0.074 Balance 3.61 37 7.7 19.92 2.57 4.52 -- 1.39 3.70 0.185 Balance 7.93Conventional Alloy 28.6 0.93 1.36 2.33 9.75 1.91 5.19 -- Balance --0° C., 1 atm 38 28.6 0.93 1.36 2.32 6.88 1.26 3.85 0.058 Balance 2.830° C., 1.2 atm 39 28.7 0.93 1.36 2.33 6.89 1.26 3.84 0.056 Balance 2.850° C., 2 atm 40 28.7 0.93 1.35 2.33 6.90 1.26 3.84 0.056 Balance 2.8420° C., 2 atm 41 28.6 0.93 1.36 2.33 6.87 1.26 3.83 0.055 Balance 2.8960° C., 1 atm 42 28.6 0.93 1.36 2.32 6.88 1.27 3.84 0.059 Balance 2.8860° C., 1.2 atm 43 28.6 0.93 1.35 2.32 6.87 1.27 3.84 0.056 Balance 2.8860° C., 2 atm 44 28.7 0.93 1.36 2.32 6.87 1.25 3.85 0.055 Balance 2.92100° C., 1 atm 45 28.8 0.92 1.36 2.31 6.88 1.25 3.85 0.055 Balance 2.91100° C., 1.2 atm 46 28.7 0.93 1.36 2.32 6.88 1.25 3.84 0.057 Balance 2.89100° C., 2 atm 47 28.6 0.93 1.36 2.32 6.88 1.25 3.83 0.055 Balance 2.86__________________________________________________________________________
TABLE 5______________________________________ Hydrogen Hydrogen Maximum Charge/ absorption desorption discharge discharge rate rate capacity cyclesKind (wt. %/sec.) (wt %/sec.) (mAh/g) (Number)______________________________________Alloys of the 1 0.28 0.25 357 5present 2 0.31 0.27 362 3invention 3 0.33 0.30 355 2 4 0.28 0.26 366 2 5 0.30 0.27 361 3 6 0.29 0.27 358 4 7 0.29 0.26 353 5 8 0.30 0.27 349 5 9 0.31 0.27 366 2 10 0.30 0.26 360 3 11 0.28 0.25 351 4 12 0.29 0.27 354 4 13 0.30 0.27 358 3 14 0.30 0.27 362 2 15 0.29 0.26 361 2 16 0.30 0.26 357 2 17 0.29 0.26 349 3 18 0.29 0.27 359 3 19 0.30 0.27 356 3 20 0.30 0.27 353 4 21 0.35 0.37 351 2 22 0.33 0.30 359 2______________________________________
TABLE 6______________________________________ Hydrogen Hydrogen Maximum Charge/ absorption desorption discharge discharge rate rate capacity cyclesKind (wt. %/sec.) (wt %/sec.) (mAh/g) (Number)______________________________________Alloys of the 23 0.25 0.23 361 4present 24 0.28 0.25 365 3invention 25 0.32 0.28 359 2 26 0.33 0.31 357 2 27 0.36 0.35 355 2 28 0.29 0.25 367 2 29 0.27 0.24 362 3 30 0.29 0.26 355 3 31 0.29 0.26 357 3 32 0.28 0.24 362 3 33 0.29 0.25 365 2 34 0.27 0.25 363 2 35 0.30 0.27 360 2 36 0.29 0.25 355 3 37 0.31 0.28 353 3Conventional Alloy 0.18 0.16 345 11 38 0.32 0.30 364 3 39 0.32 0.30 362 3 40 0.31 0.27 363 3 41 0.31 0.28 364 3 42 0.31 0.27 364 3 43 0.31 0.27 360 3 44 0.32 0.29 361 3 45 0.31 0.29 362 3 46 0.31 0.28 361 3 47 0.31 0.27 361 3______________________________________ | The present invention provides a hydrogen occluding alloy exhibiting high hydrogen absorption and desorption rates, and excellent initial activation in practical use, and a method of making it. There is provided a hydrogen occluding alloy having a composition comprising, by wt %, 32 to 38% of rare earth elements essentially consisting of La and/or Ce, 0.5 to 3.5% of Al, 0.5 to 10% of Mn, 0.005 to 0.5% of hydrogen, optionally 0.1 to 17% of Co, and the balance being Ni and unavoidable impurities; wherein the alloy has a microstructure characterized in that fine rare earth element hydride is dispersively distributed in a matrix having a CaCu 5 -type crystal structure in a ratio of 0.5 to 20% by area. There are also provided electrodes and batteries containing such alloys, and methods of making and using such electrodes and batteries. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application is a 35 U.S.C. §§371 national phase conversion of PCT/JP2011/002031, filed Apr. 10, 2011, which claims priority of Japanese Application No. 2010-202966, filed Sep. 10, 2010, the contents of which are incorporated by reference herein. The PCT International Application was published in the Japanese language.
TECHNICAL FIELD
The present invention relates to a wristband, in particular, a wristband for identifying a person by winding it around his/her wrist or ankle. The wristband is, for example, for a patient in a medical field or a visitor in an amusement center.
BACKGROUND ART
Conventionally, a wristband is wound in a ring shape placed around a wrist or an ankle by fastening both ends of the band together with fasteners made of plastics placed at both ends of a band body having a belt shape. Since this fastener is relatively expensive, there is a need to manufacture a wristband at lower cost.
There is a cheap wristband formed in a label type having an adhesive layer on a rear surface thereof without including the above fasteners. Both ends of this type band are adhered to each other. However, there is a problem that a user may intentionally peel off an adhesion portion of the wristband and thus one wristband may be reused by two or more users as an unauthorized use, for example, when a wristband, like one of label type, is used as tickets for an amusement center.
Of course, also in a medical field, there is a problem that the wristband, which was removed from a patient, could be mistakenly wrapped on an ankle or a wrist of other patients if the wristband once installed is used again.
In addition, there is a problem that it is difficult to fulfill the function of fracture for the reason that a notch portion formed on both ends for unauthorized use is not located at an adhesion portion (an overlapping portion), if both ends were not accurately, surely and carefully adhered along a predetermined length when both ends of a wristband of label type are adhered.
SUMMARY OF INVENTION
Technical Problem
The present invention has been made based on the above circumstances. It is an objective of the present invention to provide a wristband without the use of fasteners made of plastics, which can be produced at low cost in a structure in a label type.
It is another objective of the present invention to provide a wristband capable of preventing a patient from taking others' by mistake or unauthorized use.
It is another objective of the present invention to provide a wristband which because of fracture is difficult to return to an original state when an adhesion portion of the writstband is temporarily peeled off for the purpose of unauthorized use.
It is another objective of the present invention to provide a wristband, in which a fracturing notch used for preventing unauthorized use can be located at an adhesion portion (an overlapping portion) of both ends by securely and easily making a ring shape starting from a belt shape.
Solution to Problem
The present invention concerns a label wrapped around an object, like a wrist or ankle, or any other object and is focused on forming a fracturing notch in at least one of a first winding region and a second winding region. The regions are respectively located in the left and right ends of a printing region of the label in which specific information for indentifying a patient or a visitor is printed, and also forming an adhesion position check mark in at least one of a first winding region and a second winding region.
In an aspect of the present invention, a wristband comprises: a band base material in a belt shape; an adhesive layer formed on a rear surface of the band base material; and a mount temporarily attached to a rear surface of the adhesive layer. The band base material comprises: a printing region printable with specific information, a first winding region and a second winding region respectively located in the left and right ends of the printable region so as to be wound around a subject like a wrist or an ankle together with the printing area. At least one of the first winding region and the second winding region is formed with a fracturing notch. The adhesive layer is exposed when the mount located on the rear surface of the first winding region or the second winding region is peeled off. The exposed adhesive layer is adhered to the band base material side of the second winding region or the first winding region to form a ring shape winding on the wearer by overlapping each other. At least one of the first winding region and the second winding region is formed with an adhesion position check mark.
The fracturing notch may be located in an overlap region of the first winding region and the second winding region to form a ring shape.
The fracturing notch may have a plurality of cut lines along the length of the wristband.
The fracturing notch may be formed with a cut line having a tip portion in zigzag in a forward or reverse direction of the wristband.
The fracturing notch may be formed with a cut line extending in a width direction of at least one of the first winding region and the second winding region.
The mount may be formed with a cut line for peeling off the mount on the rear surface of the first winding region or the second winding region.
The fracturing notch may be formed in the vicinity of the adhesion position check mark.
The band base material band may be formed with a half-cut for removal.
The mount may be embossed to ensure breathability with no feeling of wrongness even when in direct contact with skin.
Advantageous Effects of Invention
In the wristband according to the present invention, a fracturing notch is formed in at least one of a first winding region and a second winding region respectively located in the left and right ends of a printable region in which specific information for indentifying a patient or a visitor is printed, and an adhesion position check mark is formed in at least one of a first winding region and a second winding region. Therefore, at least one of a first winding region and a second winding region having a fracturing notch can be adhered securely and easily to the other second winding region or first winding region by looking an adhesion position check mark. Then, it is difficult to peel off an adhesion portion while keeping the original state. A fracturing notch in an adhesion portion of the first winding region and the second winding region is fractured surely when an adhesion portion is peeled off for the purpose of unauthorized use, and thus unauthorized use should be prevented. It is thereby possible to avoid the errors during installation and removal of the wristband in the medical field.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is a plan view illustrating a wristband 1 according to an example of the present invention.
FIG. 2 is a rear view illustrating the wristband 1 .
FIG. 3 is a cross sectional view in III-III line of FIG. 1 .
FIG. 4 is a cross sectional view in IV-IV line of FIG. 1 .
FIG. 5 is a cross sectional view illustrating a state where the wristband 1 in a belt shape is formed to the wristband 1 in a ring shape.
FIG. 6 is a cross sectional view illustrating a state where the wristband 1 in a ring shape is wound around a subject W.
FIG. 7 is a perspective view illustrating a case where the wristband 1 is being removed from the subject W in a portion of a first winding region 6 or a mark 14 in a semicircle shape.
FIG. 8 is a perspective view illustrating a case where the wristband 1 is being removed from the subject W in a portion of second winding region 6 .
DESCRIPTION OF EMBODIMENTS
The present invention provides a wristband capable of being prevented from unauthorized use. Since an adhesion position check mark is formed in at least one of a first winding region and a second winding region having a fracturing notch, at least one of the first winding region and the second winding region can be surely adhered to the other of the second winding region or the first winding region while looking at the region adhesion position check mark. Thus, the function of the fracturing notch in the overlapping region of the first winding region and the second winding region is surely fulfilled without having to pay much attention to operation in winding.
EXAMPLES
Referring to FIGS. 1 to 8 , is a wristband 1 according to an example of the present invention is described. In particular, as shown in FIG. 3 , the wristband 1 comprises a band base material 2 in a belt shape, an adhesive layer 3 formed on a rear surface of the band base material 2 , and a mount 4 temporarily attached to a rear surface of the adhesive layer 3 .
The band base material 2 may be a synthetic paper which is based on, for example, polypropylene (PP), polystyrene (PS), polyethylene (PE) or the like, and mixed with or coated with a white pigment on its rear surface. Thus, by providing the base material 2 with opacity, and fitness for printing and smoothness, the band base material 2 is excellent for weather resistance, water resistance and printability. The band base material 2 has a printing region 5 located at the center extending substantially in a longitudinal direction thereof, and a first winding region 6 and a second winding region 7 located respectively in the left and right ends of the printing region 5 .
The printing region 5 is printable with specific information to identify a patient or a visitor using bar codes or any other means such as characters or symbols, and further, if necessary, an IC chip (not shown) capable of storing much more information. The first winding region 6 and the second winding region 7 are possibly wound together with the printing region 5 around a subject W ( FIGS. 5 and 6 ) such as a wrist or an ankle of a patient or a visitor.
The adhesive layer 3 may be of any type having adhesiveness or cohesiveness in a strength required, and preferably may be an ordinary paste or a strengthened paste.
A mount 4 is formed of a transparent material or the like, such as a relatively thin film and it has the strength required. The mount 4 is preferably formed with an embossed surface 8 on a rear surface thereof to ensure proper breathability with the skin even when that rear surface is in direct contact with skin, so that there is no uncomfortable feeling when installed. A position detection mark 9 ( FIGS. 2 and 3 ) is printed in advance on the rear surface of the mount 4 . When a continuous body of wristbands comprising a plurality of wristbands 1 successively disposed is installed in a printer (not shown) and transported toward the transport direction R (FIG. 1 ( 1 )) shown by arrow, the position detection mark 9 is detected using any sensor (not shown). Thus, above noted specific information, and the like, is possibly printed on a predetermined position in the printing region 5 .
Further, a transverse peel-off cut line 10 is formed at a location along the axial direction of the wristband 1 on a boundary portion of the first winding region 6 in the rear surface of the mount 4 to enable peel off a peeling region 4 A of the mount 4 on the rear surface of the second winding surface 7 . Alternatively, the peel-off cut line 10 may be formed on a boundary portion of the second winding region 7 if the mount 4 on the rear surface of the second winding region 7 is removed. A peeling region 4 A of the mount 4 on the rear surface of the first winding region 6 or the second winding region 7 can be peeled off to possibly expose the adhesive layer 3 of this winding region.
A fracturing notch 11 is formed in at least one of the first winding region 6 and the second winding region 7 . In an example in the drawings a fracturing notch 11 is shown, formed in the first winding region 6 . The notch portion 11 has, arrayed along the longitudinal direction of the wristband 1 , a plurality of cut lines 12 in zigzag which cut lines extending in the width direction of the first winding region 6 , which are relatively shorter.
The cut line 12 in zigzag may be formed of perforations, full cut lines or any type of notch, which is difficult to break under a usual external force, but easy to break under an external force with which an adhesion portion of the first winding region 6 and the second winding region 7 is compulsorily peeled off. In addition, the cut line 12 in zigzag may also be formed towards the central portion of the band base material from a portion located inward slightly from both edges of the left and right ends of the first winding region 6 , and in case of perforation and the like, an end portion may face the both edges of the left and right ends. In an enlarged view as shown in FIG. 1 , however, in the cut line 12 in zigzag, preferably one of the notch tip portions 12 A or apices of the zigzag is directed forward (for example, the transport direction R of the printer) of the wristband 1 , and the other notch tip portion 12 B is directed backward (the opposite direction from the transport direction R) of the wristband 1 . It is desirable to provide the cut line 13 in the width direction and formed in perforation, since it is formed in a proximal end of a mark 14 , as described below preferably, in a semicircular shape portion 14 .
The mark 14 is in a semicircular shape and is formed protruding at the upstream end of the first winding region 6 . The cut line 13 which extends in the width direction is formed at the proximal end of the mark and that line extends in the width direction of the first winding region 6 .
A first adhesion position check mark 15 (an adhesion position check mark) in a circular shape is printed in advance in the center of the mark 14 in the first winding region 6 . Therefore, the cut line 13 in the width direction, for the fracturing notch 11 , is formed in the vicinity of the first adhesion position check mark 15 . A second adhesion position check mark 16 (an adhesion position check mark) in a ring shape is formed in the second winding region 7 to act as an counterpart of the first adhesion position check mark 15 .
FIG. 5 is a cross sectional view illustrating a state where the wristband 1 in a belt shape is formed to the wristband 1 in a ring shape. FIG. 6 is a cross sectional view illustrating a state where the wristband 1 is wound around a subject W in a ring shape. In addition, a cut for separation is not formed in the mount 4 in the coupling region 1 A between another wristband 1 which is located upstream of the first winding region 6 . The mount 4 in the coupling region 1 A and the mount 4 (the peeling region 4 A) in the rear surface of the first winding region 6 are mutually and successively integrated, and the coupling region 1 A and the peeling region 4 A can be easily peeled off from the wristband 1 (the first winding region 6 ) by peeling off the mark 14 of the first winding region 6 from the coupling region 1 A.
As shown in FIG. 5 , the peeling region 4 A is peeled off and the adhesive layer 3 exposed in the rear surface of the first winding region is adhesively overlapped to the front surface of the band base material 2 in the second winding region 7 to constitute the overlapping region 17 (the adhesion region) and form a ring shape in such a way that it goes around the subject W. Thus, since the fracturing notch 11 is formed in the first winding region 6 , and the wristband 1 in a belt shape is possibly formed into a ring shape (a closed circle) in such manner that the fracturing notch 11 is located in the overlapping region 17 of the first winding region 6 and the second winding region 7 .
Note that, as shown by the virtual leader line in FIG. 4 , the band base material may be formed with a half cut 18 for removal to make it easier to break the wristband 1 as a proper process after finishing use thereof.
When using the wristband 1 as configured above, as shown in FIG. 6 , the wristband 1 in a ring shape is attached to the subject W. As described above, the peeling region 4 A of the mount 4 can be easily peeled off from a portion of the mark 14 in a semicircular shape in the first winding region with the connection region 1 A of the wristband 1 located in the mark 14 side in a semicircular shape in the first winding region 6 .
In a state that the adhesive layer 3 of the rear surface of the first winding region 6 is exposed, as shown in FIG. 5 , if the first winding region 6 is adhered to the second winding region 7 so that the first adhesion position check mark 15 of the first winding region 6 is put together to the second adhesion position check mark 16 of the second winding region 7 , the wristband 1 can easily attached to the subject W in a ring shape with not so much attention, as above, in a state where the fracturing notch 11 is securely located at the overlapping region of the first winding region 6 and the second winding region 7 .
Described below is the where the wristband is removed in unauthorized way to reuse it. FIG. 7 is a perspective view illustrating a case where the wristband 1 is being removed from the subject W in a portion of a first winding region 6 or a mark 14 in a semicircle shape. Conversely, FIG. 8 is a perspective view illustrating a case where the wristband 1 is being removed from the subject W in a portion of second winding region 6 .
As shown in FIG. 7 , when trying to remove wristband from a portion thereof located in the first winding region 6 or from the mark 14 in a semicircular shape, the cut line 13 in the width direction (the fracturing notch 11 ) of the mark 14 is cut off easily, and the mark 14 is separated from the first winding region 6 . It becomes thereafter difficult to return the wristband to the original state, and unauthorized use is prevented as a result. Even when the cut line 13 in the width direction is not cut off, the first winding region 6 is continuously removed from the second winding region 7 and the band base material 2 begins cutting from particularly the tip portion 12 B of the cut line 12 along the zigzag, and it becomes similarly difficult to return the wristband to the original state and unauthorized use is prevented as a result.
As shown in FIG. 8 , when trying to remove the band base material from a portion located in the second winding region 7 , the band base material 2 begins cutting from particularly the tip portion 12 A of the cut line 12 in zigzag and it becomes similarly difficult to return the wristband to the original state and unauthorized use is prevented as a result.
Thus, since it is possible to prevent unauthorized use, of course, and to produce the wristband 1 in the form of label at low cost, the wristband 1 can be discarded without reusing the issued wristband 1 , even including in the medical field after removing the first winding region 6 or the second winding region 7 from the subject W.
The example described above, describes an example in which the fracturing notch 11 is formed in the first winding region 6 . However, in the present invention, a fracturing notch 11 may be formed in the second winding region 7 and then the first winding region may be adhered to the second winding region 7 by removing the peeling region 4 A of the mount 4 on the rear surface in the first winding region 6 .
In addition, the form or the shape of the notch for fracture of the present invention is not limited to the example described above. Any type can be employed as long as a type which is difficult to return to the original state after fracture surely when an adhesion portion is temporarily peeled off for the purpose of unauthorized use. In addition, any type of an adhesion position check mark is also employed as long as the overlapping region 17 (an adhesion region) can be formed enough to the first winding region 6 and the second winding region 7 . | In a wristbhaving a label-like structure, fracturing notches for preventing unauthorized use are positioned where the two ends of the band are to be glued together. If temporary peeling of the glued ends is attempted, the wristband breaks reliably and it is difficult to return it to the original state. If fracturing notches ( 11 ) are formed on either a first winding region ( 6 ) or a second winding region ( 7 ), which are positioned at left and right ends of the printing region ( 5 ). The wristband is configured so that a ring shape can be formed by overlapping and adhering the adhesive layer on the rear surface of one of shape, the first winding region ( 6 ) or the second winding region ( 7 ) onto the other winding region. An adhesion position check mark ( 15, 16 ) is formed on either the first winding region ( 6 ) or the second winding region ( 7 ). | 1 |
FIELD OF THE INVENTION
The present invention relates to a paper coating composition providing improved printability and printing quality. More particularly, the present invention relates to a composition providing a coated paper for gravure printing that will ensure faithful reproduction of dots, excellent gloss and dry picking resistance and which undergoes minimum time-dependent deterioration in terms of these desirable characteristics.
BACKGROUND OF THE INVENTION
The feature that distinguishes gravure printing from other printing methods is its ability to produce pictures with range of tones by varying the thickness of ink which is achieved by means of varying the depth of ink cells on the printing surface of the plate. Because of this characteristic, the gravure-printed matter exhibits ample gradations of sharp definition and offers wide ranges of colors, contrasts and tones.
In order to make the most of these advantages of gravure printing, the paper substrate to be gravure-printed must allow for high fidelity of dot reproduction. However, in the highlights of gravure print, dots often fail to be formed by ink transfer and the resulting print does not have the intended quality. This problem is particularly serious with coated paper which inherently has excellent printing quality. Improvements of dot reproduction on coated paper for gravure printing are of primary concern to the paper industry because the commercial value of the coated paper is largely dependent on its ability to faithfully reproduce dots.
Styrene-butadiene latices have been extensively used as pigment binders in coated paper for gravure printing, but they are not completely satisfactory for the purpose of faithful dot reproduction and their ability in this respect is further decreased if they are used in combination with water-soluble polymers such as starch commonly used as thickeners or water retention aids. Another serious problem that has been encountered in using styrene-butadiene latices as pigment binders is that even if coated paper as manufactured has a dot reproducing ability that is satisfactory for practical purposes, this ability will be considerably deteriorated with a lapse of time.
Acrylic ester-based emulsions are known as pigment binders that ensure faithful dot reproduction and will not undergo any substantial deterioration with a lapse of time. However, coated paper using such emulsions has a low surface strength (i.e., low dry picking resistance) and is apt to foul the surfaces of supercalendering rolls.
As a result of various studies made in order to eliminate these problems with the conventional pigment binders, the present inventors found that by using a pigment binder made of a copolymer with a specified composition, a coated paper suitable for gravure printing can be provided that ensures faithful dot reproduction without undergoing any time-dependent deterioration, which exhibits a superior dry picking resistance, and which will not foul the surfaces of rolls used in supercalendering. The present invention has been accomplished on the basis of this finding.
SUMMARY OF THE INVENTION
The paper coating composition of the present invention comprises:
(A) a pigment, and
(B) a copolymer emulsion prepared by polymerizing a monomer mixture containing:
(i) 5 to 40 wt% of an α-olefin of the formula:
CH.sub.2 ═CH--R.sub.1
wherein R 1 is a hydrogen atom or an alkyl group having 1 to 12 carbon atoms;
(ii) 30 to 90 wt% of a vinyl ester of the formula: ##STR2## wherein R 2 , R 3 and R 4 are each a hydrogen atom or an alkyl group having 1 to 18 carbon atoms;
(iii) 1 to 30 wt% of at least one unsaturated carboxylic acid ester selected from the group consisting of an acrylic acid ester in which the alkyl moiety thereof has 1 to 18 carbon atoms and a methacrylic acid or dibasic unsaturated carboxylic acid ester in which the alkyl moiety thereof has 1 to 18 carbon atoms; and
(iv) 0.1 to 10 wt% of an unsaturated carboxylic acid.
DETAILED DESCRIPTION OF THE INVENTION
Examples of the α-olefin used as the component (i) in the present invention include ethylene, propylene, butene-1, hexene-1, and dodecene-1, with ethylene being particularly preferred.
Examples of the vinyl ester used as the component (ii) in the present invention include vinyl acetate, vinyl propionate, vinyl butyrate, vinyl pivalate, vinyl laurate and vinyl versatate, with vinyl acetate or mixtures thereof with other vinyl esters being particularly preferred.
The unsaturated carboxylic acid ester used as the component (iii) in the present invention is selected from the group consisting of acrylic acid esters in which the alkyl moiety thereof has 1 to 18 carbon atoms and methacrylic acid or dibasic unsaturated carboxylic acid esters in which the alkyl moiety thereof has 1 to 18 carbon atoms. Illustrative examples include methyl acrylate, ethyl acrylate, butyl acrylate, amyl acrylate, hexyl acrylate, heptyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, decyl acrylate, lauryl acrylate and stearyl acrylate; methyl methacrylate, butyl methacrylate, amyl methacrylate, hexyl methacrylate, 2-ethylhexyl methacrylate, dodecyl methacrylate, lauryl methacrylate and stearyl methacrylate; and dibutyl and bis(2-ethylhexyl)dilauryl esters of fumaric acid, maleic acid and itaconic acid. These compounds may be used as mixtures. Particularly preferred unsaturated carboxylic acid esters are those in which the alkyl moiety thereof has 5 to 14 carbon atoms and mixtures thereof with one or more of the above-described unsaturated carboxylic acid esters.
Examples of the unsaturated carboxylic acid used as the component (iv) include acrylic acid, methacrylic acid, itaconic acid, maleic acid, and fumaric acid, as well as monoesters of polybasic unsaturated carboxylic acids such as itaconic acid, maleic acid and fumaric acid. Particularly preferred compounds are acrylic acid and methacrylic acid.
The proportions of the monomer components (i) through (iv) are critical to the purpose of the present invention. They are 5 to 40 wt% for the α-olefin (i), 30 to 90 wt% for the vinyl ester (ii), 1 to 30 wt% for the unsaturated carboxylic acid ester (iii), and 0.1 to 10 wt% for the unsaturated carboxylic acid (iv). Preferred ranges are 10 to 30 wt% for (i), 50 to 85 wt% for (ii), 2 to 20 wt% for (iii) and 0.5 to 5 wt% for (iv).
If the content of the α-olefin (i) is less than 5 wt%, the desired dot reproduction is not ensured, and if its content exceeds 40 wt%, great difficulty will be involved in manufacturing the intended copolymer on a commercial scale, and in addition, the adhesion to the substrate will decrease to cause a reduced dry picking resistance or increase the chance of fouling the surfaces of rolls used in supercalendering.
If the content of the vinyl ester (ii) is less than 30 wt%, the adhesion to the substrate will decrease to cause a reduced dry picking resistance or increase the chance of fouling the surfaces of supercalendering rolls. If its content exceeds 90 wt%, the chance that inadequate dot reproduction will occur is increased.
If the content of the unsaturated carboxylic acid ester (iii) is less than 1 wt%, the desired dot reproduction is not ensured, and if its content exceeds 30 wt%, the frequency of the surfaces of supercalendering rolls being fouled will increase and the resulting print will often have a low gloss.
The content of the unsaturated carboxylic acid (iv) is particularly important for attaining the purpose of the present invention. Only when it is present in an amount of 0.1 to 10 wt% are ensured an improved adhesion to the substrate and significant improvements in dry picking resistance and dot reproduction. If the content of the component (iv) is less than 0.1 wt%, the improvement it provides is negligible, and if its content exceeds 10 wt%, the flowability of the coating composition is decreased to an undesirably low level.
The copolymer emulsion used in the present invention preferably has a glass transition point of 0° C. or below and more preferably -10° C. or below.
The copolymer emulsion used in the present invention may be prepared by copolymerizing the individual monomer components, i.e., the α-olefin, the vinyl ester, the unsaturated carboxylic acid ester, and the unsaturated carboxylic acid in an aqueous dispersion medium in the presence of a radical polymerization initiator, a pH modifying agent, an emulsifier and/or a dispersant such as protective colloid, and optionally a chain transfer agent.
The pigment (A) which is the other essential component of the composition of the present invention is selected from inorganic pigments such as kaolin, clay, talc, calcium carbonate, satin white, aluminum hydroxide and titanium oxide and organic synthetic pigments such as polystyrene, a melamine-formaldehyde resin and a urea-formaldehyde resin. These pigments may be used either singly or in combination.
In addition to the two essential components, i.e., the pigment (A) and the copolymer emulsion (B) which is comprised of the α-olefin, the vinyl ester, the unsaturated carboxylic acid ester, and the unsaturated carboxylic acid, the paper coating composition of the present invention may contain additives in amounts that will not be detrimental to the purpose of the invention. Illustrative additives include pigment binders such as a styrene-butadiene latex, an acrylic acid ester-based emulsion, starch, modified starch, casein and polyvinyl alcohol; thickeners or water retention aids such as starch, carboxymethyl cellulose, sodium alginate and carboxy-modified acrylic acid ester-based synthetic thickeners; and pigment dispersants such as sodium polyacrylate, sodium tripolyphosphate and sodium pyrophosphate. Other conventional additives may also be incorporated in the composition of the present invention, and they include preservatives, defoamers, coloring agents such as dyes and pigments, and any other agents for imparting special properties such as waterproofing agents and water repellants.
The paper coating composition of the present invention which contains as the essential components the pigment (A) and the copolymer emulsion (B) which is comprised of the α-olefin, the vinyl ester, the unsaturated carboxylic acid ester, and the unsaturated carboxylic acid may be applied to a paper substrate by any conventional means such as a blade coater, an air knife coater or a roll coater, dried by conventional methods, and if desired, supercalendered, whereby the intended coated paper suitable for gravure printing is obtained.
The following examples are provided in order to further illustrate the present invention. In the examples, all parts and percents are by weight on a solids basis.
EXAMPLE 1
An autoclave equipped with a temperature control unit and a stirrer was charged with an aqueous solution consisting of ion-exchanged water (130 parts), polyoxyethylene nonylphenol ether (4 parts), sodium lauryl sulfate (1 part), hydroxyethyl cellulose (1 part), acetic acid (0.05 part), sodium acetate (0.2 part) and Rongalite (0.5 part). The autoclave was purged with nitrogen and ethylene gases under stirring.
As the temperature in the system was held at 50° C., the autoclave was charged with 34 parts of vinyl acetate and an ethylene gas until the pressure in the system reached 70 kg/cm 2 . Thereafter, 15 parts of 12% aqueous ammonium persulfate and a monomer mixture consisting of 57 parts of vinyl acetate, 6 parts of 2-ethylhexyl acrylate and 3 parts of acrylic acid were added over a period of 5 hours, throughout which the reaction temperature was held at 50° C., and an additional ethylene gas was fed to maintain the polymerization pressure at 70 kg/cm 2 . After completion of the polymerization, aging was conducted at 50° C. for 1 hour.
The resulting emulsion had a solids content of 50% and was composed of 30% of ethylene, 64% of vinyl acetate, 4% of 2-ethylhexyl acrylate, and 2% of acrylic acid.
Using this copolymer emulsion, a paper coating composition was prepared by the following procedures.
Ninety parts of kaolin clay, 10 parts of heavy calcium carbonate, 0.4 part of a sodium polyacrylate-based dispersant and 0.2 part of sodium hydroxide were dispersed in a suitable amount of water to make a pigment slurry. To this slurry, 7 parts of the previously obtained copolymer emulsion and 0.3 part of Primal ASE-60 (a trade name of Japan Acrylic Chemical Co., Ltd. for an acrylic thickener) were added and stirred well to make an intimate mixture. The pH of the mixture was adjusted to 9.5 with an aqueous sodium hydroxide solution, and by addition of a suitable amount of water, a paper coating composition with a solids content of 63% was obtained.
This composition was applied to one side of a medium quality paper (basis weight, 70 g/m 2 in accordance with TAPPI T-410) with an experimental blade coater to provide a coating having a solids content of 8 g/m 2 on a dry basis. The coating was dried with hot air at 120° C. for 30 seconds. The coated paper was passed twice through supercalendering rolls at 60° C. and at a linear pressure of 60 kg/cm, whereby a product falling within the scope of the present invention was obtained.
The resulting coated paper was held for 24 hours at 20° C. and at 65% RH (relative humidity) in preparation for the following tests.
(1) Adaptability to gravure printing:
The paper was printed with a xylene solvent-based gravure ink in accordance with the "Method of Testing Paper for Its Adaptability to Gravure Printing" described in J. Tappi No. 24 (by the Printing Bureau, Ministry of Finance, Japan). The fidelity of dot reproduction on the paper was visually evaluated by the following criteria: 5, excellent to 1, poor.
(2) Gloss:
The paper was printed with a xylene-solvent based gravure ink in accordance with the "Method of Testing Paper for Its Adaptability to Gravure Printing" described in J. Tappi No. 24 (by the Printing Bureau, Ministry of Finance, Japan). The gloss of the solid printed areas was evaluated by the "Testing Method for 75 Specular Gloss of Paper and Paperboard" described in JIS P 8142.
(3) Dry picking resistance:
The paper was overprinted with a tack-graded ink (#15) on an RI printing machine (Akira Seisakusho Co., Ltd.) and the resistance of the paper to picking was visually evaluated by the following criteria: 5, excellent to 1, poor.
(4) Time-dependent change under accelerated conditions:
The sample was subjected to the test (1) as above after exposure to light in a fadeometer for 5 hours.
(5) Fouling of supercalendering rolls:
The fouling of the surfaces of the rolls through which the coated paper was passed twice for supercalendering was visually evaluated by the following criteria: 5, excellent to 1, poor.
The results of the tests (1) to (5) are summarized in Table 1 below.
EXAMPLES 2 TO 5
Four different samples of copolymer emulsions were prepared as in Example 1 except that the types or amounts of the monomer components were varied as shown in Table 1. Using these samples, paper coating compositions were prepared as in Example 1, and they were applied to base paper to produce coated papers which were then subjected to the tests (1) to (5) as in Example 1. The test results are summarized in Table 1.
COMPARATIVE EXAMPLES 1 TO 6
Paper coating compositions were prepared as in Example 1 except that the copolymer emulsions were replaced by those which were outside the scope of the present invention (Comparative Examples 1 to 4) and commercial products of a styrene-butadiene latex (Comparative Example 5) and an acrylic acid ester-based emulsion (Comparative Example 6), both of which are customarily used in coated paper for gravure printing. These compositions were applied to base paper to make comparative coated paper samples which were then subjected to the tests (1) to (5) as in Example 1. The formulations of the emulsions used and the results of the tests conducted are shown in Table 1.
TABLE 1__________________________________________________________________________ Adaptability Emulsion Formulation to GravureExample & Unsaturated Unsaturated PrintingComparative Vinyl Carboxylic Carboxylic As After Exposure Gloss Dry Picking Fouling of Super-Example No. α-Olefin Ester Acid Ester Acid Coated in Fadeometer (%) Resistance Calendering__________________________________________________________________________ RollsExample 1 E 30% VA 65% EHA 4% AA 1% 5.0 4.8 83.1 4.8 4.8Example 2 E 10% VA 75% EHA 10% AA 5% 5.0 4.8 83.9 5.0 5.0Example 3 E 10% VA 67% MA 20% AA 3% 5.0 4.8 83.4 5.0 5.0Example 4 E 25% VA 67% EHA 5% MAA 3% 5.0 4.8 83.6 5.0 4.8Example 5 E 15% VA 73% EHA 10% AA 2% 5.0 4.8 83.5 5.0 4.8Comparative E 5% VA 90% EHA 5% -- 3.0 2.8 83.6 3.8 3.5Example 1Comparative E 25% VA 22% EHA 50% AA 3% 3.8 3.5 81.4 2.3 2.0Example 2Comparative -- VA 85% EHA 10% AA 5% 3.0 2.8 83.2 4.0 4.0Example 3Comparative E 3% VA 95% -- AA 2% 2.5 2.3 83.5 4.3 4.0Example 4Comparative Styrene-butadiene latex 3.8 1.0 83.3 4.5 4.5Example 5 (commercial product A)Comparative Acrylic acid ester-based emulsion 4.0 3.5 83.5 1.5 1.5Example 6 (commercial product B)__________________________________________________________________________ Abbreviations: E, ethylene; VA, vinyl acetate; EHA, 2ethylhexyl acrylate; MA, methyl acrylate; AA, acrylic acid; MAA, methacrylic acid
While the invention has been described in detail and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope thereof. | A paper coating composition is disclosed, which comprises:
(A) a pigment, and
(B) a copolymer emulsion prepared by polymerizing a monomer mixture containing:
(i) 5 to 40 wt % of an α-olefin of the formula:
CH.sub.2 ═CH--R.sub.1
wherein R 1 is a hydrogen atom or an alkyl group having 1 to 12 carbon atoms;
(ii) 30 to 90 wt % of a vinyl ester of the formula: ##STR1## wherein R 2 , R 3 and R 4 are each a hydrogen atom or an alkyl group having 1 to 18 carbon atoms;
(iii) 1 to 30 wt % of at least one unsaturated carboxylic acid ester selected from the group consisting of an acrylic acid ester in which the alkyl moiety thereof has 1 to 18 carbon atoms and a methyacrylic acid or dibasic unsaturated carboxylic acid ester in which the alkyl moiety thereof has 1 to 18 carbon atoms; and
(iv) 0.1 to 10 wt % of an unsaturated carboxylic acid. The paper coating composition of the invention provides improved printability and printing quality and is particularly useful for gravure printing. | 3 |
This nonprovisional application is based on Japanese Patent Application No. 2005-167111 filed with the Japan Patent Office on Jun. 7, 2005, the entire contents of which are hereby incorporated by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a method of measuring a coefficient of dynamic friction between a golf ball and a collisional plate when the golf ball collides with the collisional plate. Analysis of such measurement allows for prediction of a coefficient of dynamic friction at the time of hitting of a golf ball by an actual golf club and can facilitate adjustment of a spin rate of the golf ball.
2. Description of the Background Art
Spin rate of a golf ball is an important characteristic that controls flying distance performance and controllability. A golf ball having high spin rate is able to rapidly stop on the green due to back spin, and is controllable such that its flying path is a draw or a fade by applying side spin to a golf ball. For this reason, golf balls of high spin rate are favored by professional golfers and low-handicapped golfers.
Contrarily, golf balls having low spin rate are inferior in controllability due to their small back spin, however, they are superior in that they can achieve large flying distances. Therefore, they are frequently used by high-handicapped golfers.
Conventionally, spin rate is adjusted by making adjustments on various factors such as rigidity of the entire golf ball, its distribution, degree of rigidity of outermost layer, thickness of outermost layer, distribution of specific gravity of the entire golf ball and the like. For example, U.S. Publication No. 2002/0019268A1 proposes a multilayered golf ball which realizes a larger launch angle and a smaller back spin compared with conventional golf balls.
Meanwhile, in view of golf clubs, depth, width, size, shape, arranging interval of grooves, punch marks or the like formed in a face plane of a club head, as well as surface roughness of the face plane are adjusted. In one known approach, for example, surface roughness or the like of a face plane is changed depending on the club number so that the lower the number of club head, or the relatively smaller the loft angle, the smaller friction coefficient the face plane has, and that the higher the number of club head, the larger friction coefficient the face plane has (see Japanese Patent Laying-Open No. 2004-000675).
SUMMARY OF THE INVENTION
As described above, a friction coefficient that contributes to a spin rate of a golf ball depends on the combination of a type of golf ball and a surface structure of a golf club head. And, estimation of friction coefficients of a golf club head against different golf balls would facilitate designing of spin rate. The present invention provides a method of readily designing spin rate of a golf ball, wherein a collisional plate which is mounted in a detachable manner is created as a model of a golf club head, and a coefficient of dynamic friction is measured by bringing a golf ball into collision with the collisional plate, and then based on the measurement, a contact force and a coefficient of dynamic friction at the time of collision between an actual golf club head and the golf ball are estimated.
The present invention provides a method for measuring a coefficient of dynamic friction between a golf ball and a collisional plate when the golf ball collides with the collisional plate disposed aslant at a predetermined angle with respect to a flying direction of the golf ball. The method includes concurrently obtaining a time function Fn(t) of contact force in the direction perpendicular to the collisional plate, and a time function Ft(t) of contact force in the direction parallel with the collisional plate; and determining as a coefficient of dynamic friction, a maximum value of a time function M(t) of ratio between Fn(t) and Ft(t) represented by M(t)=Ft(t)/Fn(t).
The collisional plate is adjustable at an angle (α) range of 10 degrees to 90 degrees with respect to the flying direction of the golf ball. Preferably, the collisional plate is mounted in a detachable manner. Further, the collisional plate may be attached with a pressure sensor.
In the measuring method of the present invention, the golf ball may be emitted vertically upward via an air gun system to collide with the collisional plate.
In the measuring method of the present invention, an initial velocity of the golf ball before collision with the collisional plate, and an angle of collisional plate may be controlled by a control box.
In the measuring method of the present invention, the collisional plate may include a substrate, a pressure sensor, a superficial plate, and a main bolt for integrally fixing them.
In the measuring method of the present invention, the substrate may be made of steel.
In the measuring method of the present invention, the superficial plate may include a main body and a covering plate, and a coefficient of dynamic friction may be measured while arbitrarily designing and varying a material, a planner shape and a surface structure of the covering plate.
In the measuring method of the present invention, the main body of the superficial plate may be made of stainless steel.
In the measuring method of the present invention, the covering plate of the superficial plate may be made of a titanium alloy containing 6% by mass of aluminum and 4% by mass of vanadium.
The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic view of a measuring method used in the present invention.
FIG. 2 is an enlarged partial section view of a collisional plate used in FIG. 1 .
FIG. 3 is a graph showing Ft(t), Fn(t) and M(t).
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The measuring method of the present invention uses a detachably mounted collisional plate, and hence is a very close model for hit of an actual golf club. It can analyze collision phenomena such as contact force and a friction phenomenon at the time of collision between an actual golf club and a golf ball by measuring a coefficient of dynamic friction.
(Method of Measuring Coefficient of Dynamic Friction)
A method of measuring a coefficient of dynamic friction between a golf ball and a collisional plate in the present invention will be explained below with reference to a measuring apparatus of FIGS. 1 and 2 .
In FIG. 1 , a golf ball 2 is emitted upward perpendicularly in the vertical direction from an emitter 1 of an air gun system. Golf ball 2 is emitted at an initial velocity in the range of about 20 to 50 m/second, for example. The initial velocity of golf ball 2 is calculated by measuring a distance and a blocking time difference between a first sensor S 1 and a second sensor S 2 .
Golf ball 2 thus emitted is brought into collision with a collisional plate 3 set in advance at a predetermined angle (α) in the emitting direction of golf ball (flying direction). These initial velocity of golf ball and angle (α) of collisional plate are controlled in a control box 4 .
Golf ball 2 after collision is reflected in the left downward direction as shown in FIG. 1 . Fn(t) which is time-series data of force along the direction perpendicular to the collisional plate and Ft(t) which is time-series data of force along the direction parallel with the collisional plate at the time of collision are measured by a pressure sensor 22 which is attached to collisional plate 3 .
In FIG. 3 , a point PO represents a position where pressure sensor 22 starts sensing force, and generally corresponds to the point at which collisional plate 3 and golf ball 2 come into collision with each other. Fn(t) which is a contact force of perpendicular direction gradually increases from point PO, peaks at a point P 4 , comes down therefrom to reach zero at a point P 3 . Point P 3 represents a point where pressure sensor 22 no longer senses force, and generally corresponds to the point where golf ball 2 leaves collisional plate 3 .
On the other hand, a value of Ft(t) which is contact force in the direction parallel with the collisional plate (i.e., shear strength) increases with time from point P 0 , peaks at P 1 , then gradually decreases to zero at point P 2 after which it takes a negative value. Since the golf ball leaves pressure sensor 22 at point P 3 , the curve of Ft(t) sensed at pressure sensor 22 takes zero at point P 3 . An area S 1 of the region where Ft(t) takes positive values within the area surrounded by the curve of Ft(t) and the time axis represents impulse where shear strength is positive. On the other hand, an area S 2 of the region where Ft(t) takes negative values within the area surrounded by the curve of Ft(t) and the time axis represents impulse where shear strength is negative. Impulse S 1 acts in such a direction that promotes back spin, and impulse S 2 acts in such a direction that restrains back spin. Here, impulse S 1 takes a larger value than impulse S 2 , and a value obtained by subtracting impulse S 2 from impulse S 1 contributes to back spin of a golf ball.
A coefficient of dynamic friction can be derived by calculating a maximum value of M(t) which is obtainable by Ft(t)/Fn(t).
(Concurrent Measuring Method of Spin Rate of Golf Ball)
In the measuring apparatus of FIG. 1 , spin rate, speed, and launch angle of a golf ball that collides with the collisional plate are measured. This may be used as identification data for determining correlation between calculated value of M(t) and spin rate.
In FIG. 1 , golf ball 2 that is reflected by the collisional plate is measured for spin rate, speed and flying angle of golf ball 2 during fly by a stroboscopic device Kb and a camera device Ka disposed laterally of the flying trajectory. Stroboscopic device Kb is connected to a stroboscopic power 5 , and camera device Ka is connected to a camera power 6 via a capacitor box 8 . Spin rate, speed, and flying angle may be analyzed by using a spin analyzing device 7 . Further, by comparing these analysis results with results of measured coefficient of dynamic friction, it is possible to evaluate correlation between coefficient of dynamic friction and spin rage, as well as influences of coefficient of dynamic friction on the initial velocity and flying angle of a golf ball.
(Structure of Collisional Plate)
In FIG. 2 , collisional plate 3 has a substrate 21 , pressures sensor 22 , a superficial plate 23 and a main bolt 25 for integrally fixing these elements.
Substrate 21 may be formed of any material without particular limitation insofar as it has a predetermined strength and rigidity, but preferably formed of steel. Substrate 21 is 5.0 to 20.0 mm thick. A model number of main bolt 25 is, for example, M 10 according to Japanese Industrial Standards (JIS).
Pressure sensor 22 may be implemented by a variety of products such as 3-component force sensor (model 9067) manufactured by Kistler Instrument Corp., for example. This sensor is able to measure force components in a parallel direction, a Y direction and a perpendicular direction. Although not illustrated, measurement of pressure is conducted with a charge amplifier (model 5011B of Kistler Instrument Corp.) connected to pressure sensor 22 . Pressure sensor 22 is formed in its center with a through-hole 24 through which main bolt 25 is inserted to integrally fix pressure sensor 22 with substrate 21 .
Superficial plate 23 is made up of a main body 23 a and a covering plate 23 b . The covering plate is attached to the main body in a detachable manner. By appropriately changing the material, the planner shape and the surface structure of covering plate, it is possible to create approximate models of various golf club heads and to measure coefficients of dynamic friction thereof. Main body 23 a and covering plate 23 b may be mounted in any way without special limitation, for example, via a bolt.
Main body 23 a of superficial plate 23 may be formed of any materials without limitation, but typically of stainless steel (SUS-630). The thickness of main body 23 a is typically in the range of 10 to 20 mm. Also, main body 23 a may have a planner shape which is substantially the same with that of pressure sensor 22 , such as a square 40-60 mm on a side. Into main body 23 a , a distal end of main bolt 25 is screwed. As a result, pressure sensor 22 is sandwiched and fixedly positioned between substrate 21 and main body 23 a.
As to covering plate 23 b , various materials, planner shapes and surface structures may be adopted, however, a titanium alloy (6-4Ti) containing 6 wt % of aluminum and 4 wt % of vanadium is typically used in view of evaluation of model of club head. Thickness of covering plate 23 b may be arbitrarily changed, for example, within the range of 1.0 to 5.0 mm. The planner shape of covering plate 23 b is substantially the same with that of main body 23 a , such as a square 40-60 mm on a side, for example. Also, covering plate 23 b has a surface roughness which may be arbitrarily adjusted, for example in the range of 2 to 20 μm in terms of 10-point average roughness Rz.
Collisional plate 3 may be positioned at any angle (α) with respect to the flying direction (launching direction) of golf ball. In the present invention, the angle (α) is typically adjusted in the range of 10° to 90°. This angle corresponds to a loft angle of golf club and may be efficiently used for designing different numbers of club heads.
EXAMPLES
A coefficient of dynamic friction of a golf ball was measured using a measuring apparatus having a general structure shown in FIG. 1 and having the following specification.
1. Specification of Measuring Apparatus
(A) Emitter: air gun system
(B) Collisional plate
Substrate
Steel
Thickness: 5.35 mm
Main body
Superficial plate
Size: 56 mm×56 mm×15 mm Stainless steel (SUS-630)
Covering plate
Size: 56 mm×56 mm×2.5 mm Titanium alloy: 6-4Ti (6 wt % Al, 4 wt % V) Average roughness: 13.6 μm±2.0 μm
Angle of inclination (α)
22 degrees (with respect to flying direction of golf ball)
(C) Pressure sensor
3-component force sensor (model 9067), product of Kistler Instrument Corp.
Charge amplifier
Model 5011B, product of Kistler Instrument Corp.
(D) Capture of contact force into PC
A pulse counter board PCI-6101 (manufactured by INTERFACE CORPORATION) was used. With a 16-bit PCI pulse counter board with 4 channels, measurement suited for a specific application may be realized in four counter modes. The maximum input frequency is 1 MHz.
2. Measuring Procedure
Measurement of coefficient of dynamic friction was conducted in the following manner.
(a) Set angle (a) of collisional plate at 22 degrees with respect to flying direction of golf ball (vertical direction).
(b) Adjust air pressure of emitter 1 .
(c) Emit golf ball from emitter.
(d) Measure initial velocity of golf ball from preset distance between sensor 1 and sensor 2 and blocking time difference of golf ball therebetween.
(e) Measure contact force Fn(t) and contact force Ft(t), and calculate maximum value of Ft(t)/Fn(t).
(f) Measure spin rate of golf ball with stroboscopic device and camera device.
3. Result of Measurement
Results obtained with the above apparatus and measuring procedure are shown in FIG. 3 . From FIG. 3 , a value of M(t) is calculated as Ft(t)/Fn(t), and a maximum value is 0.21. Since Ft and Fn tend to generate noises in initial and terminal periods where contact force rises up, a maximum value of M(t) is calculated while trimming an early stage of the initial period and a late stage of the terminal period.
The present invention provides a method capable of adjusting a contact force between a golf ball and a golf club, and a spin rate of the golf ball when the golf ball is hit by the golf club. The present invention allows for evaluation of spin rate at the time of hitting with a golf club by measuring a coefficient of dynamic friction between a golf ball and a collisional plate in an apparatus employing a club model with the collisional plate.
Although the present invention has been described and illustrated in detail, it is clearly understood that the same is by way of illustration and example only and is not to be taken by way of limitation, the spirit and scope of the present invention being limited only by the terms of the appended claims. | By bringing a golf ball into collision with a collisional plate and measuring a coefficient of dynamic friction at this collision, contact force at the time of collision between an actual golf club and the golf ball is analyzed and spin rate of the golf ball is estimated. This invention provides a method for measuring a coefficient of dynamic friction between a golf ball and a collisional plate when the golf ball collides with the collisional plate disposed aslant at a predetermined angle with respect to a flying direction of the golf ball. The method includes concurrently obtaining a time function Fn(t) of contact force in the direction perpendicular to the collisional plate, and a time function Ft(t) of contact force in the direction parallel with the collisional plate; and determining as a coefficient of dynamic friction, a maximum value of a time function M(t) of ratio between Fn(t) and Ft(t) represented by M(t)=Ft(t)/Fn(t). | 6 |
BACKGROUND OF THE INVENTION
FIELD OF THE INVENTION
The present invention relates generally to an apparatus for determining the distance between a vehicle and a fixed object, and more particularly to a system and method for assisting a driver who is backing a tractor/trailer up to a loading dock by visually and continuously letting the driver know how close the rear of the trailer is to the loading dock, thereby providing information to the driver to prevent the trailer from being backed into the loading dock and incurring the commensurate damage associated with such a collision.
Much of the cargo moved from one location to another is moved by heavy trucks, with the most common of such trucks being a tractor/trailer combination in which a large tractor is used to tow a variety of long trailers from place to place. It will be appreciated by those skilled in the art that such trailers extend well back of the cab of the tractor pulling them. While truck drivers are generally skilled in the operation of such large tractor/trailer combinations, one of the more difficult operations which they must perform on a frequent basis is backing the trailer up to a loading dock.
The driver must ensure that the tractor/trailer is being backed up in the proper lane, which may frequently be located between two other tractor/trailers, with relatively little space therebetween. In addition, the driver must accurately gauge the distance between the rear of the trailer and the edge of the loading dock, so that the tractor/trailer can be stopped in the proper position just prior to running into the loading dock. While it is relatively easy to stop the tractor/trailer in the proper position when assisted by a second person located adjacent the loading dock and at one side of the trailer, it will be appreciated that it is difficult for the driver alone to back the trailer to a position just short of the loading dock.
When the driver of a tractor/trailer does not have assistance from a second person, in order to avoid backing the trailer into the loading dock it may be necessary for the driver to stop at a position which may be well short of the loading dock, get out of the tractor, go to the rear of the trailer to see how much distance remains between the rear of the trailer and the loading dock, and then return to the cab of the tractor and continue backing up. More than one such trip from the cab of the tractor to the rear of the trailer may be necessary to properly position the rear of the trailer at the loading dock without hitting the loading dock. With the heavy weight of the tractor/trailer, particularly when the trailer is loaded, it will be appreciated that significant damage can be done to the rear of the trailer even at very slow speeds.
It is accordingly the primary objective of the present invention that it provide the driver of a tractor/trailer with an apparatus and a related method of operating the apparatus for providing an indication of the distance remaining between the rear of the trailer and a loading dock or other similar fixed object as the trailer is backed toward the loading dock or other fixed object. It is a further objective of the collision avoidance system of the present invention that it be permanently mountable on a loading dock or other fixed object in a manner such that it will reliably determine the distance between the rear of a trailer being backed toward the loading dock or other fixed object and the loading dock or other fixed object. It is a related objective of the collision avoidance system of the present invention that it be capable of providing a minimum offset distance between the rear of a trailer and the loading dock or other object such that there may be an adjustable small space, e.g. a few inches, between the rear of the trailer and the loading dock or other object when the tractor/trailer is properly parked at the loading dock.
It is also an objective of the collision avoidance system of the present invention that it be operable in a manner not requiring the driver of the tractor/trailer to get out of the cab of the tractor in order to determine the distance between the rear of the trailer and the loading dock or other fixed object. It is a related objective of the collision avoidance system of the present invention that a display be installed on the loading dock or other fixed object in a position which may easily be viewed by the driver while the driver is located in the cab of the tractor. It is a further related objective of the collision avoidance system of the present invention that the display mounted on the loading dock or other fixed object may be viewed by the driver either by looking out the window of the cab of the tractor and back toward the loading dock or other fixed object, or by looking in the side view mirror of the tractor back toward the loading dock or other fixed object.
The collision avoidance system of the present invention must be of a construction which is both durable and long lasting, and it should also require little or no maintenance to be provided by the user throughout its operating lifetime. In order to enhance the market appeal of the collision avoidance system of the present invention, it should also be of relatively inexpensive construction to thereby afford it the broadest possible market. Finally, it is also an objective that all of the aforesaid advantages and objectives of the collision avoidance system of the present invention be achieved without incurring any substantial relative disadvantage.
SUMMARY OF THE INVENTION
The disadvantages and limitations of the background art discussed above are overcome by the collision avoidance system of the present invention. With this invention, a transducer module is mounted onto the side of a loading dock or other fixed object toward which the rear of a trailer will be backed. The transducer module contains an ultrasonic transducer and circuitry for operating the ultrasonic transducer to determine the distance between the back of the trailer and the loading dock or other fixed object. An offset adjustment switch is provided to determine the minimum offset distance, e.g. a few inches, between the rear of the trailer and the loading dock or other object which will exist when the tractor/trailer is properly parked at the loading dock. When the rear of the trailer is located this minimum distance away from the loading dock or other fixed object, the transducer module will provide an indication that the distance between the rear of the trailer and the loading dock is zero.
The collision avoidance system of the present invention also provides a display module which may be mounted on the loading dock or other fixed object at a location which will be to the side (preferably, the left side) of the rear of the trailer when it is properly parked at the loading dock or other fixed object. Thus, the display module may easily be seen by the driver of the tractor as the trailer is backed up toward the loading dock or other fixed object. From this description, it will be apparent to those skilled in the art that the display may be viewed by the driver of the tractor by either looking out the window of the cab of the tractor and back toward the loading dock or other fixed object, or by looking in the side view mirror of the tractor back toward the loading dock or other fixed object. The display module will display the distance between the rear of the trailer and the loading dock or other fixed object which is determined by the transducer module.
In the preferred embodiment, the display module contains first and second numeric displays which are preferably of different colors so that the desired display will be highly distinguishable from the other numeric display. A first numeric display is conventional and is viewable by looking directly at the display module, and a second numeric display is reversed (a mirror image) such that it is viewable by looking at the reflection of the display module in a mirror. Thus, the first numeric display may be viewed by the driver of the tractor by looking out the window of the cab of the tractor and back toward the loading dock or other fixed object, while the second numeric display is reversed and may be viewed by the driver of the tractor by looking in the side view mirror of the tractor back toward the loading dock or other fixed object.
The transducer module is electrically connected to the display module by a cable extending therebetween, and the collision avoidance system is supplied with electrical power to operate it. In a first optional aspect of the collision avoidance system of the present invention, an audible alarm may be provided when the transducer module determines that there is zero distance between the rear of the trailer and the loading dock or other fixed object. In a second optional aspect of the collision avoidance system of the present invention, a second display module may be located at a remote location, such as, for example, adjacent the side of the cab of a tractor as the tractor/trailer is being backed toward the loading dock or other fixed object.
It may therefore be seen that the present invention teaches an apparatus and a related method of operating the apparatus for providing an indication of the distance remaining between the rear of the trailer and a loading dock or other similar fixed object as the trailer is backed toward the loading dock or other fixed object. The collision avoidance system of the present invention is permanently mountable on a loading dock or other fixed object in a manner such that it will reliably determine the distance between the rear of a trailer being backed toward the loading dock or other fixed object and the loading dock or other fixed object. The collision avoidance system of the present invention is also capable of providing a minimum offset distance between the rear of a trailer and the loading dock or other object such that there may be an adjustable small space, e.g. a few inches, between the rear of the trailer and the loading dock or other object when the tractor/trailer is properly parked at the loading dock.
The collision avoidance system of the present invention is operable in a manner not requiring the driver of the tractor/trailer to get out of the cab of the tractor in order to determine the distance between the rear of the trailer and the loading dock or other fixed object. A display for the collision avoidance system of the present invention may be installed on the loading dock or other fixed object in a position which may easily be viewed by the driver while the driver is located in the cab of the tractor. The display of the collision avoidance system of the present invention which is mounted on the loading dock or other fixed object may be viewed by the driver either by looking out the window of the cab of the tractor and back toward the loading dock or other fixed object, or by looking in the side view mirror of the tractor back toward the loading dock or other fixed object.
The collision avoidance system of the present invention is of a construction which is both durable and long lasting, and which will require little or no maintenance to be provided by the user throughout its operating lifetime. The collision avoidance system of the present invention is also of inexpensive construction to enhance its market appeal and to thereby afford it the broadest possible market. Finally, all of the aforesaid advantages and objectives of the collision avoidance system of the present invention are achieved without incurring any substantial relative disadvantage.
DESCRIPTION OF THE DRAWINGS
These and other advantages of the present invention are best understood with reference to the drawings, in which:
FIG. 1 is a functional schematic diagram of a collision avoidance system constructed according to the teachings of the present invention and having a transducer module and a display module which are electrically interconnected by a cable having modular connector plugs at each end thereof;
FIG. 2 is a front plan view of the display module of the collision avoidance system of the present invention illustrated in FIG. 1;
FIG. 3 is a front plan view of a loading dock having the transducer module and the display module of the collision avoidance system of the present invention illustrated in FIG. 1 installed thereon;
FIG. 4 is a view from the left side of a tractor and trailer which is being backed up to the loading dock illustrated in FIG. 3, with the rear of the trailer being located seventeen feet (plus a minimum offset distance) from the loading dock, and also showing a front view of the display module of the collision avoidance system of the present invention which is inset above the loading dock indicating seventeen feet;
FIG. 5 is a view similar to the view illustrated in FIG. 4, with the rear of the trailer being located eight feet (plus the minimum offset distance) from the loading dock, with the display module indicating eight feet; and
FIG. 6 is a view similar to the view illustrated in FIG. 4, with the rear of the trailer being located nine feet (plus the minimum offset distance) from the loading dock, with the display module indicating zero feet.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The preferred embodiment of the collision avoidance system of the present invention has two primary components which are designed to be located at separate locations which are physically spaced apart from each other. These two components are illustrated in FIG. 1, which depicts a transducer module 20 which is electrically connected to a display module 22 by a cable 24. The cable 24 has a modular plug 26 located at one end thereof, and a modular plug 28 located at the other end thereof. The modular plug 26 is for electrical connection to the transducer module 20, while the modular plug 28 is for electrical connection to the display module 22.
Referring first to the transducer module 20, it may be seen that the modular plug 26 of the cable 24 may be plugged into a modular jack 30 to electrically connect the transducer module 20 to the cable 24. The cable 24 will supply electrical power through the modular jack 30 to power conditioning circuitry 32 which conditions the electrical power to remove voltage spikes and other undesirable transients. The power conditioning circuitry 32 then supplies the conditioned power to a microprocessor 34 and transducer circuitry 36. In the preferred embodiment, the microprocessor 34 is an 8-bit microprocessor.
The transducer circuitry 36 operates an ultrasonic transducer 38, which is a combination ultrasonic transmitter/receiver such as a K series high frequency piezo transmit/receiver transducer which is available from the Polaroid OEM Group. The transducer circuitry 36 may be a ranging module for use with the K series high frequency piezo transmit/receiver transducer, and is also available from the Polaroid OEM Group. Such ultrasonic transmitter/receivers use acoustic echo transducer technology to measure distances without physically measuring the distances, at least in a conventional sense. By transmitting an ultrasonic signal from the ultrasonic transducer 38 at a first location to a surface at a second location (such as the rear of a trailer, for example), and then measuring the amount of time it takes the ultrasonic signal to reach the surface and be reflected back to the ultrasonic transducer 38, the distance between the ultrasonic transducer 38 and the surface may be determined with a high degree of precision.
The principle of operation of ultrasonic distance measuring devices is relatively simple. The ultrasonic transducer 38 is oscillated at or near its resonant frequency by the transducer circuitry 36, and the ultrasonic transducer 38 then produces an ultrasonic signal. Since the ultrasonic transducer 38 produces a relatively directional ultrasonic signal, the ultrasonic signal may be aimed in a desired direction toward a surface (such as the rear of a trailer, for example). When the ultrasonic signal reaches the surface, it will be reflected back toward the ultrasonic transducer 38, which will detect the reflected acoustic signal.
By measuring the amount of time that it takes for the ultrasonic signal to complete its round trip between the ultrasonic transducer 38 and the surface onto which it was directed (from the ultrasonic transducer 38 to the surface and back to the ultrasonic transducer 38), the distance between the ultrasonic transducer 38 and the surface can be computed. Typically, the ultrasonic transducer 38 is pulsed by the transducer circuitry 36 briefly, with the time between the pulse and the return signal being measured. This measured interval is supplied by the transducer circuitry 36 to calculating circuitry in the microprocessor 34, which calculates the distance between the ultrasonic transducer and the surface based upon the time between the pulse and the return signal and provides an output indicating the calculated distance through the modular jack 30 to the display module 22 via the cable 24.
It is desirable to provide a minimum offset distance of a few inches or so between the rear of the trailer and the loading dock or other object when the tractor/trailer is properly parked at the loading dock. When the rear of the trailer is located this minimum offset distance from the loading dock or other fixed object, the transducer module 20 should provide an indication that the distance between the rear of the trailer and the loading dock is zero. The exact amount of this minimum offset distance may be selected using an offset adjustment switch 40 to provide this information to the microprocessor 34. In the preferred embodiment, the offset adjustment switch 40 is a four pole DIP switch providing 16 different minimum offset distances which may range from zero to fifteen inches, for example. Thus, for example, if the offset adjustment switch 40 is set for three inches, the transducer module 20 will indicate zero when the rear of the trailer is located three inches from the ultrasonic transducer 38.
Referring now to the display module 22, it may be seen that the modular plug 28 of the cable 24 may be plugged into a modular jack 42 to electrically connect the display module 22 to the cable 24. A step-down transformer 44 is used to lower the level of AC voltage supplied to the display module 22. The lowered AC voltage is supplied from the step-down transformer 44 to a rectifier/regulator 46 which, as its name implies, rectifies the lowered AC voltage and provides as an output a regulated DC voltage. The regulated DC voltage from the rectifier/regulator 46 is supplied to the cable 24 through the modular jack 42 to provide power to the transducer module 20.
The regulated DC voltage from the rectifier/regulator 46 is also supplied to transient suppression circuitry 48, a microprocessor 50, a display driver 52, and a display 54. The output from the microprocessor 34 in the transducer module 20 (which is indicative of the distance between the ultrasonic transducer 38 and the rear of a trailer) is supplied via the cable 24 through the modular jack 42 to the transient suppression circuitry 48, where it is conditioned by the transient suppression circuitry 48 to remove voltage spikes and other undesirable transients. The transient suppression circuitry 48 supplies the conditioned signal to the microprocessor 50, which in the preferred embodiment is also an 8-bit microprocessor.
The microprocessor 50 converts the conditioned signal to a numeric value, which is then supplied to the display driver 52. The display driver 52 is used to operate the display 54, which in the preferred embodiment is a two digit numeric display ranging from zero to nineteen (feet). The display 54 will be more fully described in conjunction with the description of FIG. 2 below.
Optionally, the display module 22 may also include peripheral circuitry 56 which may be used to drive additional information output components. The rectifier/regulator 46 is connected to supply regulated DC voltage to the peripheral circuitry 56. The peripheral circuitry 56 may be used to drive an audio transducer 58 to produce an audible alarm when the transducer module 20 goes from one foot to zero (indicating that the rear of the trailer is located the predetermined minimum offset distance of three inches from the ultrasonic transducer 38).
The peripheral circuitry 56 is also shown as being connected to provide the numeric value from the microprocessor 50 to a modular jack 60, which is electrically connected to a second display unit 62 by a cable 64. The cable 64 has a modular plug 66 located at one end thereof, and a modular plug 68 located at the other end thereof. The modular plug 66 is for electrical connection to the display module 22, while the modular plug 68 is for electrical connection to the second display unit 62.
It may be seen that the modular plug 66 of the cable 62 may be plugged into the modular jack 60 to electrically connect the display module 22 to the cable 64. The modular plug 68 of the cable 64 may be plugged into a modular jack (not shown) in the second display unit 62 to electrically connect the second display unit 62 to the cable 64. The second display unit 62 would consist of a display driver similar to the display driver 52, and a display similar to the display 54. The second display unit 62 may be located in a location different from the location of the display module 22.
Referring next to FIG. 2, the display module 22 is illustrated with its display 54 having a first two digit numeric display 70 and a second two digit numeric display 72. Both the first and second two digit numeric displays 70 and 72 have a first digit which may be selectively actuated to produce a one and a seven segment second digit which may be selectively actuated to produce any number between zero and nine. Thus, each of the first and second two digit numeric displays 70 and 72 may selectively be operated to produce a number between zero and nineteen (feet). In operation, the first and second two digit numeric displays 70 and 72 are tied together so that each produces the same number.
The first two digit numeric display 70 is located on the top half of the display 54, and in the preferred embodiment is of a first color. The second two digit numeric display 72 is located on the bottom half of the display 54, and in the preferred embodiment is of a second color. The first two digit numeric display 70 will display a number in conventional fashion, and is viewable by looking directly at the display module 22. The second two digit numeric display 72 will display a reversed or mirror image of the number, such that it is readable only by looking at the reflection of the second two digit numeric display 72 in a mirror. In the preferred embodiment, the first two digit numeric display 70 is red and the second two digit numeric display 72 is green; it is essential that the two colors chosen are clearly distinct from each other.
Referring now to FIG. 3, a loading dock 80 of conventional height is illustrated. A wood bumper 82 is mounted on the side of the loading dock 80 such that the top surface of the wood bumper 82 is level with the top surface of the loading dock 80. A metal bumper plate 84 is mounted onto the central portion of the wood bumper 82, and extends approximately two-thirds of the width of the wood bumper 82. A metal plate 86 having the same width as the metal bumper plate 84 is located on the top surface of the wood bumper 82, and extends onto the top surface of the loading dock 80.
The transducer module 20 is mounted slightly below the bottom of the metal bumper plate 84 and is aligned with the center of the metal bumper plate 84. In practice, the transducer module 20 will be recessed inwardly from the metal bumper plate 84 to protect the transducer module 20 from damage. Thus, the total offset distance programmed into the transducer module 20 will have to be the desired minimum offset distance (the distance between the rear of the trailer and the metal bumper plate 84 on the loading dock 80 when the trailer is properly parked) plus the distance that the ultrasonic transducer 38 of the transducer module 20 is recessed inwardly from the metal bumper plate 84.
The display module 22 is mounted at the top of the loading dock 80 to the right of the transducer module 20 (as viewed when facing the loading dock from the direction from which trailers will be backed in). When a trailer is backed up to the loading dock 80 such that its back end is centered with the metal bumper plate 84 on the loading dock 80, the display module 22 will be located several feet to the left of the trailer.
A first segment of conduit 88 extends between the transducer module 20 and the display module 22, and the cable 24 (illustrated in FIG. 1) will be located inside the first segment of conduit 88. A second segment of conduit 90 extends from the display module 22, and wires (not shown) are located inside the second segment of conduit 90 to supply power to the collision avoidance system of the present invention.
Referring next to FIG. 4, a tractor 92 is illustrated as it is backing a trailer 94 toward the loading dock 80. In addition to the display module 22 mounted on the loading dock 80, an enlarged display module 22 is also inset into FIG. 4 above the loading dock 80. In FIG. 4, the rear of the trailer 94 is indicated by the display 54 on the display module 22 to be seventeen feet from the metal bumper plate 84 on the loading dock 80. Note that the first two digit numeric display 70 may be read by the driver of the tractor 92 by looking out the window of the cab of the tractor 92 and back toward the loading dock 80. Alternately, the second two digit numeric display 72 may be read by the driver of the tractor 92 by looking in the side view mirror of the tractor 92 back toward the loading dock 80.
Referring next to FIG. 5, the tractor 92 is shown to have backed the trailer 94 closer to the metal bumper plate 84 of the loading dock 80. The rear of the trailer 94 is indicated by the display 54 on the display module 22 to be eight feet from the metal bumper plate 84 on the loading dock 80.
Referring finally to FIG. 6, the tractor 92 is shown to have backed the trailer 94 to within the minimum offset distance (three inches) of the metal bumper plate 84 of the loading dock 80. At this point, the rear of the trailer 94 is indicated by the display 54 on the display module 22 to be zero feet from the metal bumper plate 84 on the loading dock 80. If the audio transducer 58 (illustrated in FIG. 1) is utilized, at this point it will produce an audible alarm. Note that if the second display unit 62 is utilized, it may, for example, be mounted at a point immediately to the left of the cab of the tractor 92 at the location at which it is shown in FIG. 5.
It may therefore be appreciated from the above detailed description of the preferred embodiment of the present invention that it teaches an apparatus and a related method of operating the apparatus for providing an indication of the distance remaining between the rear of the trailer and a loading dock or other similar fixed object as the trailer is backed toward the loading dock or other fixed object. The collision avoidance system of the present invention is permanently mountable on a loading dock or other fixed object in a manner such that it will reliably determine the distance between the rear of a trailer being backed toward the loading dock or other fixed object and the loading dock or other fixed object. The collision avoidance system of the present invention is also capable of providing a minimum offset distance between the rear of a trailer and the loading dock or other object such that there may be an adjustable small space, e.g. a few inches, between the rear of the trailer and the loading dock or other object when the tractor/trailer is properly parked at the loading dock.
The collision avoidance system of the present invention is operable in a manner not requiring the driver of the tractor/trailer to get out of the cab of the tractor in order to determine the distance between the rear of the trailer and the loading dock or other fixed object. A display for the collision avoidance system of the present invention may be installed on the loading dock or other fixed object in a position which may easily be viewed by the driver while the driver is located in the cab of the tractor. The display of the collision avoidance system of the present invention which is mounted on the loading dock or other fixed object may be viewed by the driver either by looking out the window of the cab of the tractor and back toward the loading dock or other fixed object, or by looking in the side view mirror of the tractor back toward the loading dock or other fixed object.
The collision avoidance system of the present invention is of a construction which is both durable and long lasting, and which will require little or no maintenance to be provided by the user throughout its operating lifetime. The collision avoidance system of the present invention is also of inexpensive construction to enhance its market appeal and to thereby afford it the broadest possible market. Finally, all of the aforesaid advantages and objectives of the collision avoidance system of the present invention are achieved without incurring any substantial relative disadvantage.
Although an exemplary embodiment of the collision avoidance system of the present invention has been shown and described with reference to particular embodiments and applications thereof, it will be apparent to those having ordinary skill in the art that a number of changes, modifications, or alterations to the invention as described herein may be made, none of which depart from the spirit or scope of the present invention. All such changes, modifications, and alterations should therefore be seen as being within the scope of the present invention. | A device for determining the distance between the rear of a trailer and a loading dock is disclosed which assists a driver backing the trailer up to the loading dock by visually and continuously letting the driver know how close the rear of the trailer is to the loading dock, thereby providing information to prevent the rear of the trailer from colliding with the loading dock. The distance between the back of the trailer and the loading dock is determined by an ultrasonic transducer which is mounted onto the side of the loading dock toward which the rear of the trailer will be backed. A display module mounted on the loading dock provides a numeric indication of the distance between the rear of the trailer and the loading dock. In the preferred embodiment, both a conventional numeric display (which may be read by the driver by looking out the window of the cab of the tractor and back toward the loading dock) and a reversed or mirror image (which may be read by the driver by looking in the side view mirror of the tractor back toward the loading dock or other fixed object) are provided on the display module. | 8 |
BACKGROUND OF THE INVENTION
1. The Field of the Invention
The field of the art to which this invention pertains is radio wave communication and use of antenna with stream-lined shape supports.
2. Description of the Prior Art
The prior art has covered antenna as in U.S. Pat. No. 2,635,186 and 1,962,202 but has not carried such concept of a cover to provide such a degree of support as will provide a mobile C.B. antenna that maintains fixed shape and stable angular orientation with respect to horizontal ground on a moving mobile vehicle. Antenna flexibility has been the goal and as a result during motion the transmission and reception characteristics of C.B. radio system using such antenna has not provided the reception and transmission characteristics of which the 5 watt power permitted for citizen's band radio has been capable.
SUMMARY OF THE INVENTION
By this invention, a practical and efficient broadcast system is provided whereby the transmission and reception characteristics of C.B. radio systems is substantially improved by provided mechanical support to the radiator of the antenna so that the wave pattern produced by such broadcast system is optimized, whereby the full power of the electrical input to the antenna is provided for effective transmission to an audience antenna rather than utilizing only weaker portion of the radiation pattern for such transmission. Further, such maintenance of the orientation and shape of the antenna provides for improved angular relationship of such antenna to the wave front provided by other C.B. broadcasts and a consquent improvement in effective reception of signal met by such antenna and system. The size of non-magnetic support means provided for the electrical antenna structure also permits incorporation of identification and location means to locate and identify stolen antenna units of this type.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagrammatic block diagram of a transceiver showing the component units thereof.
FIG. 2 is a side view of one embodiment of the antenna unit and positioner assembly in its operative antenna position.
FIG. 3 is a top oblique view of the antenna of FIG. 2 and antenna positioner assembly in the retracted position of the antenna.
FIG. 4 is a detail in zone 4A of FIG. 2.
FIG. 5 is a vertical longitudinal section of the antenna along the plane 5A--5A of FIG. 6.
FIG. 6 is a front view of the antenna of FIG. 5 as seen along the direction of the arrow of 6A of FIG. 5.
FIG. 7 is a top or plan view along the direction of arrow 7A of FIG. 5.
FIG. 8 is a diagrammatic plan view of a stage of the operation of the system of the antenna unit and CB radio of FIGS. 1-7.
FIG. 9 is a diagrammatic vertical sectional view along the vertical plane 9A--9A of FIG. 8. FIGS. 8 and 9 show one car 22 moving in direction 23 on one lane 28 of road 29 while another car 122 moves in lane 128 of road 29 adjacent lane 28 and in direction 123, opposite to direction 23.
FIGS. 10 and 11 illustrate the structure and operation of an alternative embodiment of antenna unit positioner assembly. FIG. 12 is an enlarged view of structures in zone 12A of FIG 10.
FIG. 13 shows one alternative location of the antenna unit 60 on the car bumper.
FIG. 14 shows other alternative locations of an antenna unit as 60--on the trunk lip, at 60.1 and on the rain gutter of the side roof line of car 22 at 60.2.
FIG. 15 is a diagrammatic showing of circuit the receiving circuit in assembly 20 compared with relations of some of the structural elements in a conventional circuit.
DESCRIPTION OF THE PREFERRED EMBODIMENT
A block diagram of a typical CB Class D transceiver 20 utilizing the electrical components 27 of the antenna assembly 60 is provided in FIG. 1 wherein the radio 20 is a combination of transmitter, receiver and power supply components with the transmitter and receiver circuits all contained on the same chassis with the some of the circuits such as the audio output modulator 38 and the audio amplifier 39 used in both circuits. In the transceiver 20 the antenna electrical elements 62 and 66 (shown in FIGS. 5 and 15) feed the radio frequency amplifier, 31; that amplifier, together with the oscillator 36 feeds the mixer and provides signal to the intermediate frequency amplifier 33 and that amplifier transmits audio signal to the detector 34 when in receiver mode; that audio signal is passed by switch 41 to audio amplifier 39 to audio output in modulator 38 and by switch arm 42 to speaker 40. The electrical power source 30 is connected to all these units 31-34, 36, 37, 38 and 39. Units 38 and 39 are used in both transmitting and receiving functions.
The conventional multiple position switch M1 provides for switching the circuits from a receiving mode of operation when its switch arms 41, 42, and 43 are connected to the switch pole referred to as "R" while the same circuits provide, in conventional manner, for transmission of radio signals when the switch arms 41, 42, and 43 of switch M1 are connected to the terminal T therefor.
Unit 20 is a multichannel transceiver provided by selector switch 45 with separate crystal oscillators so that the radio frequency amplifier therefor at 37 may deliver one of several of preselected signals to the electrical components 27 of antenna assembly 60; such unit 20 may be 3 inches high and 81/2 inches wide and 81/2 inches deep while providing the maximum R.F. input of 5 watts permitted by the Federal Communication Commission. The power to radio 20 is limited by the 5 watt maximum requirement of the Federal Communication Commission to operate in the Class D channel frequencies (26.965 to 27.255 megacycles).
A detailed schematic of such circuit elements of a conventional solid state transceiver is set out on pages 30-31 of "Understanding and Using Citizens Band Radio" published by Allied Radio Shack, January, 1971, Library of Congress Catalog Card Number: 67-18973.
The antenna unit 60 comprises a straight thin conductive element 62 and a rigid plastic shell 64 as well as a loading coil or loader 66; the antenna unit 60 is firmly held by a rigid plate 68 to a support therefor on the roof 24 of the car 22 and a coaxial cable 70 extends from the loader 66 to the transceiver 20.
In an early embodiment, the antenna unit or assembly 60 shown in FIGS. 5 - 7 had an overall length of 36 inches with an overall maximum width (left to right in FIGS. 6 and 7) of 2 inches and an overall maximum thickness (top to bottom of FIG. 7 and left to right of FIG. 5) of 4 inches; however, a 39 inch high base loaded antenna as unit 42 R-01208 WV as shown at page 216 of Lafayette catalogue 760 (of Layfayette Radio Electronics Corp., 111 Jericho Turnpike, Long Island, New York, 1976) may form the antenna element 62 and loading coil 66 and is firmly supported in a rigid plastic body as 64 as shown in FIG. 5 with a maximum of four inches of antenna wire 62 extending from the top of the rigid plastic body or shell 64; shell 64 tapers from the wide bottom at the bottom face 165 thereof to the top of the triangular shell 64. The plastic shell or cover is a strong plastic as polyethylene and is firmly attached to the surface of the antenna wire 62 and the loading coil 66 and so avoids any movement of the antenna wire 62 with respect to the loading coil 66. Further, the loading coil, as shown in FIG. 5, is firmly attached to the support therefor that is attached to the car, such as plate 68 in FIG. 2 or the bumper in FIG. 13 or the trunk deck. Such attachment to plate 68 may be by rigid nuts 161 and 162 firmly fixed to a rigid threaded hollow shaft 163 and to the plate 68. The bottom face 165 of the mass of plastic body 64 is firmly pressed against and attached to the top surface of the plate 68 and accordingly provides a rigid dimensionally stable support structure for the antenna unit 60. Antenna unit 60 always operates as a quarter wave antenna and may have a height of 72 inches with a loader coil compensating for any excess capacitance of the antenna. In the overall, the firm weather-proof plastic plastic body 64 may be made of a high strength vinyl or polyethylene plastic or other weather-proof material and has sufficient size as 4 to 12 inches width and 2 to 4 inches thickness to limit the oscillation of the topmost portion 167 of the antenna unit 60 to a movement in the longitudinal plane (the plane parallel to that shown in FIG. 5) of less than one inch at the antenna top of the unit 60 when it is six feet long and less than 1/2 inch in a 3 foot length of the antenna unit 60 at a velocity of 40 miles per hour of car 22.
The mass of electrically nonconductive material forming shell 64 is sufficiently large that magnetically identifiable indicia such as a number bearing plate 159 may be located in that mass and may be identified by conventional magnetic readout means held at the surface of shell 64. Numbers formed of magnetically identifiable ink as used in bank checks may be located within the mass of shell 64 and covered by opaque paint on the surface, as 158, of mass of shell 64 which mass is non-conductive electrically and non-magnetic, or the outer surface of the mass of shell 64, as at 158, adjacent the magnetic indicia as 159 may be so roughened that structures on a small plate or identifying indicia as magnetic numbers are not visible to the human eye from the outside of the plastic mass of shell 64. The magnetic indicia are located below the vertical level of the antenna conductor 62 to avoid or minimize interference with the electromagnetic radiation passing thereto and therefrom. The electrically conductive antenna element 62 is an extensible antenna. It is formed of a bottom larger hollow rigid steel tube 67 of about 1/8 inch internal diameter firmly electrically and mechanically attached by threaded connection to the top of the upper cylindrical tubular portion 69 that is electrically conductive and formed of steel (and may be chrome plated) and has a smooth slidable fit in tube 67. An adjustable threaded set screw 58 is located in a threaded hole 59 therefor in the mass of shell 64 and the tube 67 and locks the movable portion 69 relative to the fixed portion 67. Screw 58 is made of plastic or other non-magnetic material to not interfere with the radio waves to and from antenna unit 60.
In the embodiment of FIGS. 2-4, the unit 60 is firmly attached onto a rigid plate 86. A pivotal piano hinge 72 is firmly attached to plate 68 and to a rigid base 74. The base 74 comprises a rear wall 75, a front wall 76, a left wall 77, and a right wall 78. Each of the walls 75-78 is rigid and vertical and firmly attached to car roof 24 and form a cable receiving chamber 79 therebetween and, together, firmly support plate 86 and unit 60 in the positions of such parts shown in FIG. 2. The coaxial cable 70 passes through a hole at the bottom of the chamber 79 in roof 24 to the loader coil 66.
A rigid antenna receiver 90 which has an upwardly open V-shaped notch 91 formed of soft rubber at its top is fastened at its bottom 92 to the roof 24 of the car. In the raised position of the antenna unit 60 as shown in FIG. 2, a non-conductive strong waterproof nylon string cable 61 firmly attaches to a non-magnetic and electrically cable-holding overload release assembly 120 fixed to car roof 24 and holds the unit 60 in vertical position.
The cable holding assembly 120 comprises a rigid arm 121 which is pivotally supported on a T-shape base 126 fixed to roof 24. A loop on the arm 121 is attached on to a pin 132 on base 126 about which pin arm 121 pivots. The control portion 129 (right side in FIG. 4) of the arm 121 is held downward by an adjustment nut 124 on a threaded rigid shaft therefor (fixed at its bottom to roof 24) against a resilient compression spring 125 to provide adjustment of the tension with which the loop end of arm 121 (left hand end of the arm 121 as shown in FIG. 4) engages a loop 63 at the bottom end of the cable 61. A flexible non-conductive weatherproof safety rope 127 is attached to the cable 61 near the loop 63. In the operative position of antenna unit 60 as shown in FIG. 2, the safety rope 127 is loose and is also attached at one end to the base 126. On attainment of a predetermined maximum tension in cable 61, which maximum tension may be set by the nut 124, the cable 61 raises the arm 121 and disengages therefrom and provides for pivotal release of the antenna unit 60 from its erect position shown in FIG. 2 to the retracted position thereof shown in FIG. 3 by the force theretofore applied to the cable 61. Accordingly, the rigid structure of the antenna unit 60 which provides for its maintained shape and angular orientation is not a cause of any damage thereto by meeting of obstruction such as trees or garage door, inasmuch as a predetermined stress along the cable 61 provides for release of unit 60 although during operation as in FIG. 2 the rigid antenna unit 60 maintains its straight shape and a fixed angular orientation with respect to the vehicle on which supported while in 10-55 m.p.h. motion.
After the antenna unit 60 is in its retracted position on receiver 90 as in FIG. 3 the safety cable 127 serves to connect the cable 61 to the holding assembly 120 and permits an operator to locate and move the loop 63 from its release position shown in FIG. 3 to the operative position thereof as shown in FIGS. 4 and 2 and return the antenna unit 60 to its position of FIG. 2. Cable 61 holds it in such a position until an overload condition again occurs or the operator chooses to retract the antenna unit 60.
With the high frequencies used in Class D operation, antenna unit 60 provides an angle of radiation which is quite low and at these frequencies the radio energy traveling outward as a sky wave is dissipated with a coaxial type quarter wave vertical antenna of which that shown in FIG. 5 is typical. As shown in FIG. 9, the radiation pattern 84 for the R. F. wave emanated by antenna unit 60 is radially downwards at its bottom as at portions 80 and 81 of the pattern 84 and, at the top thereof is a very flat or wide cone having a very wide angle 86 along the axis 87 of the antenna wire of antenna unit on the vehicle 22.
Such radiation pattern 84 is arranged symmetrically about the axis 87 and provides a central pattern plane 88 of maximum field strength passing through the center of pattern 84 which plane 88 is parallel to the rod 29 when the central axis 87 of the antenna wire 62 is vertical. However, when the axis of a conventional C.B. antenna as axis 187 of a conventional whip antenna 160 is used on a vehicle 122 traveling in direction 123 so that the plane 188 (corresponding to the central plane 88) of the radiation pattern 184 emanating from the antenna 160 on vehicle 122 is viewed as in FIG. 9 against the horizontal plane of the road 29 its central plane of maximum field strength 188 (developed by circuit elements identical to those in assembly 20 except for the antenna unit 60) does not meet the vehicle as 22 traveling in a direction 23 along lane 28 of road 29 opposite to the direction 123 of vehicle 122 at distances of 1 to 5 miles between such vehicles as diagrammatically shown in FIG. 9. Antenna unit 60 avoids the tilting and bending of the conventional antenna when such antenna are in operation on a moving vehicle; at 20 m.p.h. the conventional 102-108 inch long antenna bends 4-6 inches at its top, at 40 m.p.h. it bends 9-12 inches and at 70 m.p.h. from 18-24 inches; tilting also occurs.
Even the conventional 39 inch antenna with a loading coil provides a deflection of 4 to 6 inches at its top at a vehicle speed of 40 m.p.h. and readily vibrates 2 to 3 inches at the top. Accordingly, the antenna 20 in moving vehicle 22 carrying an antenna unit as 60 with the vertical axis 87 of antenna wire 62 maintained vertical, has a greater effective field strength than does a moving vehicle as 122 carrying an antenna as 160 with its vertical axis 187 tilted backward by the air traversed by moving vehicle 122 at an angle 189 from the vertical.
In the conventional basic mixer oscillator circuit shown in FIG. 12 for the receiving circuit, the split tuning capacitors 101 and 102 simultaneously tune the input-mixer unit 103 and the local ocillator tank circuit as 104. The radio frequency input signal from the antenna portion 27 is applied to the base of the mixer transistor 105 and the local oscillator signal is applied to the emitter 106. (This provides a certain amount of isolation between the local oscillator 104 and the input signal from the electrical antenna elements 27.) The collector of the mixer transistor 107 is connected to the primary of an intermediate frequency transformer 108 which is in parallel with a capacitor 108. This primary coil 108 and a capacitator 109 form a 455 kHz resonant circuit. The intermediate frequency which is taken off at the output 110 is accordingly directly proportional to the input energy from the electrical antenna elements 62 and 66.
The mixer input circuit selects the desired input signal from the large number of signals present at the antenna and feeds it at 103 to the r-f signal input of the mixer stage. The tuning capacitator tunes the local oscillator and the tuning capacitator and oscillator and mixer coils are so designed the local oscillator is always tuned 455 kHz higher than the mixer input circuit whereby there is always a 455 kHz frequency difference between the local oscillator and the incoming signal. The local oscillator signal at 113 is fed to the oscillator input of the mixer stage; the mixer combines the r-f input and local oscillator and generates two new frequencies, i.e., one being the sum and the other being the difference of the two input signals, whereby a 455 kHz beat frequency is produced and amplified in the intermediate frequency amplifier. While an automatic volume control circuit is standard in radio sets, this only provides for a reduction of the input to the intermediate frequency bias network. A converter may be used in the place of a separate mixer and oscillator. The intermediate frequency output at 110 (in 33) is directly controlled by the input from the antenna electrical elements 27 and, where the axis 87 of the antenna is at an angle to the vertical and hence receives only a component less than the maximum field intensity such angular deviation from the vertical reduces the reception characteristic as well as the transmission efficiency of such antenna as above described. The apparatus 60 of this invention avoids such weakening effect on reception as well as transmission by maintaining the antenna in a continued stable vertical position and shape.
The improvement of receiving sensitivity of the antenna 60 over the conventional antenna 160 is shown in FIG. 15 and measured by that the waves of radiation pattern 184 striking the vertical element 62 of antenna 60 are at right angles thereto and accordingly are fully effective because of the total structure of antenna assembly 60 to produce electric oscillations in that conductor, while, if such conductor 62 were sloped, as shown for a hypothetical portion 262, at an angle 289 (same as 189) of the total wave energy passing in direction 292 only the portion 290 perpendicular to the direction of that sloped or tilted portion 262 (sloped like axis 187 of antenna 160) and at an angle 291 to the direction 292 would be effective to generate a response in i.f. coil 110 to the total intensity 292 of the radio wave signal passing in direction 292. The vector portion 290 is that fraction of vector portion 292 which equals the cosine of angle 291, and angles 291 and 289 are equal.
Accordingly, the vertical antenna unit 60 more effectively intersects the radio wave electromagnetic field applied thereto along a plane parallel to the road or ground as 29 than does a conventional flexible antenna as 160 which in operation on a moving vehicle is bent at an angle 189 to the vertical as such bent antenna 160 receives only a component which is expressed by the formula:
F.sub.eff = F.sub.max × cos angle 189
where:
F.sub.eff = effective portion of field meeting antenna
and
F.sub.max = radio wave field intensity at the intersection with the location of the antenna.
In the embodiment of FIGS. 10 and 11 the unit 60 is firmly attached onto a rigid plate 68 and the pivotal piano hinge 72 of which the pivotal axis extends transverse to length of car and direction of extension of antenna unit 60, is firmly attached to plate 68 and to a rigid base 74 as in FIGS. 2 and 3 and the same antenna receiver 90 is used as in FIGS. 2 and 3 and a remote control antenna unit positioner assembly 220 is provided. In the raised position of the antenna unit 60 as shown in FIG. 10 the non-conductive strong weatherproof nylon string cable 61 firmly attaches to a cable-holding and overload release assembly 219 fixed to car roof 24, like the overload release assembly 120 of FIGS. 2 and 4 in front of the antenna base 74. Assembly 219 holds the unit 60 in vertical position to the position of parts shown in FIG. 10.
A remote control antenna unit position control assembly 220 comprises a motor 221 and a cable holding and overload release assembly 219. The motor 221 is connected to and is powered by the battery of car 22 through a switch 250 therefor in cab 25 of vehicle 22. Motor 221 is attached to and drives a rigid L-shaped crank 222 with a rigid longitudinally extending arm 223. Actuation of motor 221 causes arm 223 to rotate from its counter clockwise position shown in FIG. 11 to its clockwise position shown in FIG. 10 while vehicle 22 is stationary or moving. The outer end 225 of the rigid arm 223 is attached to cable portion 263 which is non-extensible and attached to one end of a turnbuckle tightener 224. The other end of the tightener is attached to the cable 61 which is attached to the antenna unit 60 shell 64 near the upper end thereof at collar 65 as shown in FIGS. 2, 5 and 10.
The outer tip 225 of the arm 223 in the position of FIG. 10 contacts one of the arms as 229 of an 8-arm star wheel 228 which is rotatably supported on a first pair of pedestal bases 226 (only one is shown). A rigid control arm 237 is pivotally supported on a horizontally extending pin 241 which pin is supported on a second pedestal 234 which is firmly attached to car roof 24.
In assembly 219, vertical rigid threaded spring adjustment shafts 242 and 236 extend through loosely fitting holes therefor in rigid pawl positioning arm 237. A light tongue positioning compression spring 244 is held in vertically adjustable position loosely on shaft 242 by an adjustable positioning nut 243 therefor which is threaded on the shaft 242 therebelow. The bottom of shaft 242 is firmly held on roof 24. A strong compression spring 235 holds upwardly and rearwardly sloped pawl tongue portion 233 of arm 237 against a forwardly extending star wheel arm 231 (in position of parts of FIG. 10). A spring positioner shaft 236 is firmly held at its bottom on surface of roof 24. Spring 235 is positioned on shaft 236. The force in spring 235 is adjusted by nut 238 on shaft 236.
Accordingly, when the switch 250 (for and connected to motor 221) in the cab of the car 22 is connected, it moves the arm 223 clockwise from its position in FIG. 11 to position thereof as shown in FIG. 10 and thereby raises the antenna unit 60 to operative position. The tip 225 of the arm 223 then strikes and moves one of the rearwardly extending arms 230 of the star wheel 228 from an initial position thereof--the position shown for arm 229 in FIG. 12--to the position thereof shown in FIG. 12 for arm 230.
In the position of parts shown in FIG. 10, the tongue end 233 of arm 237 contacts the bottom of one of the star wheel arms as 231 and prevents the star wheel from rotating and end 225 of arm 223 from rising until a predetermined tension in cable 61 is reached. Until such amount of tension in cable 61 is reached, the star wheel 228 is held from sufficient rotation to release arm 223 and an arm thereof, as 229, holds the arm 223 in a lowered (rightward) position as shown in FIG. 12, and the antenna unit 60 in erect position as shown in FIG. 10.
Assembly 219 thus adjustably provides for release of cable 61 when needed, whereupon (after release) the unit 60 moves to the position thereof shown in FIG. 11. A light spring 244 and the nut 243 on adjustment shaft 242 holds the control arm 237 in position for the movable contact with the star wheel arms as 232 during counterclockwise rotation of the star wheel 228.
The positioner assembly 220 provides that the antenna unit 60 is restored to its vertical position as in FIG. 10 from its position in FIG. 11 while the vehicle is moving or stationary. Spring 235 is provided with a rigid internal restrainer plate 240 (itself movable on shaft 236) to limit the initial vertical length of spring 235 prior to the application of force thereto by arms 223 and 237 so that the change of spring length will be sharper with change of force in cable 61. The spring 235 may, like pedestal 226, be one of pair with a harness therebetween engaging the arm 237. Restrainer plate 240 is positioned by its adjustment nut 204 on shaft 236.
The assembly 219 thus provides a longitudinally and vertically movable pawl (tongue 233) cooperatively connected to resilient means (spring 244) restraining longitudinal movement of the pawl (out of path of arms of star wheel its counterclockwise motion) and adjustable resilient means (spring 235) limiting vertical movement of the pawl (tongue 233) for release of arm 223 when a predetermined stress on line 61 is reached.
The length of antenna cords 61 and 263 and 127 provided for horizontal positioning and full rearward extension of unit 60 from hinge 72 as shown in FIGS. 3 and 11 and holding the portion of antenna unit 60 distant from hinge 72 by the notch in antenna receiver 90 as shown in FIGS. 3 and 11 without breaking such cords. Each of tensile stress supporting cords 61 (and 61 + 263) is taut in the position thereof shown in FIGS. 2 (and 10, respectively) to assist in holding the antenna unit 60 vertical.
In a particular embodiment for a 40 inch distance from plate 86 to the attachment of cord 61 to unit 60 as shown in FIGS. 2 and 10, the rear edge of arms--which are 2 inch radius--of star wheel 228 would be 30 inches forward of hinge 72, and the loop engaging arm 121 is the same distance from hinge 72. Receiver 90 is 30 inches rearward of hinge 72; arm 223 is 13 inches long. Loop rope 127 is 28 to 30 inches long. Receiver 90 is 6 inches wide, high and thick, and the notch therein is 4 inches wide at its top and 5 inches deep, and straight sided and lined with 1/2 inch thick foam rubber all along the sides of the notch.
The upper portions of the notch sides serve as a guide for the antenna unit 60 and the lower side portions of the notch fit and hold the sides of the outwardly convex faired or curved shape of the unit 60 in the position of parts shown in FIGS. 3 and 11 with a space about 1/2 inch between the then bottom or rear edge of unit 60 and the bottom of the notch.
As shown in FIG. 1, when switch M1 is in transmission mode, microphone 35 is operatively connected, as by an amplifier as 39, a modulator as 38 and power amplifier as 37 to the electrical portion 27 (comprising radiator 62 and coil 66) of the antenna unit 60.
Plate 255 is provided to hold spring 35 on nut 238; plate 264 holds spring 244 on nut 243; a cover 269 closed at its front end covers the mechanical components of release assembly 219. | A dimensionally stable antenna unit is maintained in a stable vertical position during mobile operation of the radio of which the antenna unit is a part and accordingly improves the transmitting as well as receiving characteristics of the overall radio system. | 7 |
BACKGROUND OF THE INVENTION
This invention relates to fishing lures and methods of making them, and more particularly to improved multicolored and salt emitting soft, flexible plastic lures.
Tubular soft plastic fishing lures have been made by coating a solid metal mandrel with molten plastic resin, allowing the plastic to harden and then removing the resulting hollow tubular lure from the mandrel. Attempts to make such tubular lures with two distinct colors from two differently colored thermoplastic resins have not been successful because the plastics run together and the colors become cloudy or mix into an off color when one or both plastics is hot enough to melt. The clouding of the plastics prevents transmission of light through lures that are made from translucent plastics.
The molten plastic from which such soft plastic lures are made has been impregnated with powdered salt in order to impart a salty taste to the lures. This dispersion of finely divided salt throughout the plastic makes the lure colors dull and difficult to control, and the impregnated salt makes translucent plastic lures look cloudy instead of clear, and it diminishes the effectiveness of tiny reflective speckles dispersed within translucent plastics. Also, impregnation with salt distorts the shape of some lure bodies, and impregnation of salt into the interior of a lure delays the release and dissolving of the salt into the water. Plastic lures impregnated with powdered salt are usually lost or damaged before all of the salt can migrate from the interior of the lure into the water being fished, so the salt remaining in the lure is wasted.
OBJECTIVES OF THE INVENTION
Accordingly, it is an object of this invention to provide improved flexible soft bodied plastic fishing lures.
Another object is to provide improved salt emitting fishing lures.
An additional object is to provide multicolored soft plastic fishing lures with distinct colors that do not become cloudy or blur into each other.
Another object is to provide salt emitting fishing lures that immediately release salt into the water being fished.
A further object is to provide salt emitting fishing lures that include salt crystals large enough to attract fish by reflecting light.
An additional object is to provoke strikes from game fish by providing fishing lures with surfaces that resemble the gills of a bait fish or the body parts of an injured or spawning fish.
Another object is to provide multicolored multilayered soft bodied fishing lures that have embedded light reflecting tiny speckles that are visible through an unclouded transparent outer colored plastic layer.
A further object is to provide unitary, integral, multicolored and salt emitting soft bodied plastic fishing lures that are rugged, economical, highly attractive to fish, easy for fishermen to use, and which do not possess defects found in similar prior art fishing lures.
A further object is to provide improved methods for making each of the types of fishing lures described above.
Another object is to prevent the mixing and blurring of colors when multicolored plastic fishing lures are made by dipping a mandrel into molten thermoplastic resins.
Another object is to affix visible salt particles to the exterior surface of a plastic fishing lure, without impregnating the plastic with salt.
Other objects and advantages of the fishing lures and manufacturing methods incorporating this invention will be found in the specification and claims and the scope of the invention will be set forth in the claims.
DESCRIPTION OF THE DRAWING
FIG. 1 is a perspective view of an embodiment of a fishing lure in accord with this invention.
FIG. 2 is a schematic side view of one method step of this invention.
FIG. 3 is a schematic side view of another method step of this invention.
FIG. 4 is a schematic side view of another method step of this invention.
FIG. 5 an enlarged cross sectional schematic side view one embodiment of a fishing lure in accord with this invention.
FIG. 6 is a schematic side view of the fishing lure of FIG. 5 showing another method step.
FIG. 7 is an enlarged side view of one of the streamers produced by the method step illustrated in FIG. 6 .
FIG. 8 is a schematic side view of another method step of this invention.
FIG. 9 is a schematic side view of another method step of this invention.
FIG. 10 is an enlarged partial side view of a mandrel coated with salt grains.
FIG. 11 is a schematic side view of the coated mandrel from FIG. 10 used in another method step of this invention.
FIG. 12 is a side view of another embodiment of a fishing lure in accord with this invention.
FIG. 13 is an enlarged cross sectional view taken along the line 13 — 13 in FIG. 12 .
FIG. 14 is an enlarged fragmentary view taken generally along the line 14 — 14 in FIG. 13 .
FIG. 15 is an enlarged cross sectional schematic side view of one of the tail strands from the embodiment of FIG. 12 .
FIG. 16 is an enlarged cross sectional schematic partial side view of another embodiment of the invention.
DESCRIPTION OF THE INVENTION
The drawing shows a fishing lure 1 having an open ended, multilayered and multicolored, salt emitting, soft, flexible, unitary, integral plastic body 2 in accord with this invention, including filamentary tentacles or streamers 3 . The lure body 2 is impaled on a hook 4 that has been tied to a fishing line 5 in conventional manner. The lure body 2 should be made from colored soft, resilient, flexible synthetic thermoplastic plastisol resin formulations, such as polyvinyl chloride plasticized with esters of phathalate.
A translucent or semi-transparent colored resin will permit light to pass through the lure but will cause some diffusion of the light rays. A transparent colored resin is a special case of translucence in that the diffusion of light is so slight that objects can be clearly seen through the resin forming the lure body 2 . When the plastic resin is not cloudy and is translucent or transparent, tiny reflective particles or speckles 6 can be incorporated into the plastic and dispersed into all parts of the body 2 where they will be visible, as shown in FIG. 1 .
One embodiment of the lure 1 has an open ended multilayered and multicolored body 2 that has been made by applying three differently colored plastic layers to a circular cylindrical mandrel or rod 7 . The rod 7 is first dipped into a first supply of molten plastic 8 having a predetermined first color in a container 9 , as shown in FIG. 2 . When the rod 7 is removed from the container 9 , the rod is coated with a first inner layer 10 of plastic having the first color. Then the rod 7 coated with the first layer 10 is dipped into a second supply of molten plastic 11 having a second predetermined color in a container 12 , as shown in FIG. 3 . When the rod 7 is removed from the container 12 , the rod and first layer 10 are coated with a second intermediate layer 14 of plastic having the second color. The rod 7 , which is now coated with the first and second layers 10 and 14 , is then dipped into a third supply of molten plastic 15 having a third predetermined color in a container 16 , as shown in FIG. 4 . When the rod 7 is removed from the container 16 , the rod and first and second layers 10 and 14 are coated with a third outer layer 17 of plastic having the third color. After the plastic hardens the resulting multilayered hollow tubular lure body 2 , as shown in FIG. 5, can be removed by sliding it off of the rod 7 . The streamers 3 may be cut in the lure body 2 by a gang of knives 19 that make slices 20 that are generally parallel to the lure central axis 21 . The streamers 3 may be cut before or after the body 2 is removed from the rod 7 . FIG. 7 shows a multicolored multilayered streamer 3 .
The first, second and third colors may be different from each other and still not cause blurring of the first inner plastic layer 10 or the third outer plastic layer 17 . Blurring can be prevented by using a neutral color, such as white, for the intermediate plastic layer 14 . Blurring can also be prevented by using a secondary color such as green, for the color for the intermediate layer 14 , when the inner layer 10 and the outer layer 17 are the primary colors, such as yellow and blue, that produce the secondary color of the layer 14 . To prevent blurring when the interior layer 10 and/or the outer layer 17 are translucent or transparent, the intermediate layer 14 should not be either translucent or transparent.
To simulate the gills of a bait fish, the inner layer 10 should be colored red. As the lure body 2 is jerked through the water with a stop and go action, the streamers 3 pulse back and forth toward and the away from the body's front end 22 . This action exposes and then hides the red color of the inner layer 10 in apparently the same way the gills of a fleeing bait fish are exposed to a predator game fish, which induces the game fish to strike the lure 1 . Similar game fish strike provoking action may be obtained by coloring the inner layer 10 to resemble the intestines of an injured bait fish or the roe of a spawning fish. But these strike producing actions can not be obtained with muddied colors, so the neutral intermediate layer 14 must always be present to prevent blurring of the colors of the inner and outer layers 10 and 17 .
The lure body 2 can also be made so that it will immediately exude dissolved salt from its open tail end 24 on contact with water. To make a lure with an instant strong salty flavor, a rod 7 first should be coated with a non-aqueous parting agent, such as a petroleum based liquid like SAE 5 weight motor oil. The rod may be coated by spraying the parting agent on the rod, or by dipping a rod 7 into a container 25 of parting agent 26 , as shown in FIG. 8 . The parting agent 26 must be non-aqueous because the salt will dissolve in water based parting agents. The rod 7 coated with the parting agent 26 is then dipped into a container 27 containing discrete salt grains or particles 28 having widely varying mesh sizes. The parting agent will cause the salt grains 28 to stick to the outer surface of the rod 7 as shown in FIG. 10 . Then the rod coated with salt grains can be dipped into a container 30 of resin 31 to form a hollow tubular plastic lure body 2 , having streamers 3 , as described with regard to FIGS. 2-7. The individual salt grains 28 will be embedded in the exposed inside surface 32 of the tubular body 2 , as shown in FIGS. 13 and 14. A portion 33 of the salt grains will be exposed directly to the atmosphere and the water being fished through gaps 34 in the inside surface 32 that are formed when the plastic hardens around the salt grains on the rod 7 . The streamers 3 will also have salt grains embedded in their inner surface, as shown in FIG. 15 .
The salt emitting lure body 2 may also be made into a multilayered multicolored body as described above. After the rod 7 has been removed from the container 30 , the rod with the salt grains and a first layer 10 of plastic still on its surface would be dipped into two additional containers of differently colored plastic, as described with reference to FIGS. 2-4. FIG. 16 shows that inside surface 32 of the inner layer 10 of the lure body 2 and streamers would have grains 28 of salt embedded therein. A portion 33 of the surface of the salt grains would also be exposed to the atmosphere in this multilayered multicolored embodiment.
Preferably the salt comprises sodium chloride grains having widely varying mesh sizes. The size of the individual salt grains should be large enough to be visible to the naked eye. Thus when the visible grains reflect light the grains will give a sparkle effect to the lure when the streamers 3 pulse back and forth and when the lure inside surface 32 is visible. The salt grain sizes may vary from that of table salt to that of rock salt. These sizes should be in the range of from about 10 mesh to about 45 mesh. The salt grains 28 must be three dimensional and must not be finely divided, powdered or flaked. Using the relatively large sized grains specified above will prevent the plastic from completely encapsulating the salt, which would not allow the encapsulated salt to be exposed directly to the atmosphere and water being fished. Impregnating the plastic with finely divided salt grains would also distort the shape and color of the lure body, and make translucent and transparent plastics cloudy looking. But exposing relatively large salt grains only at the lure inner surface in accord with this invention does not cloud translucent and transparent plastic or distort lure color and shape.
While the present invention has been described with reference to particular embodiments, it is not intended to illustrate or describe all of the equivalent forms or ramifications thereof. Also, the words used are words of description rather than limitation, and various changes may be made without departing from the spirit or scope of the invention disclosed herein. It is intended that the appended claims cover all such changes as fall within the true spirit and scope of the invention. | A unitary or one-piece, integral soft bodied plastic fishing lure may be multi-layered and have two or more distinct colors. Soft bodied fishing lures may emit salt flavors directly into the adjacent water that dissolves salt grains exposed at the surface of the lures directly to the water. Methods of making the multi-colored and salt emitting lures by dipping mandrels into molten plastic and supplies of salt grains are disclosed. | 0 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This patent application is related to and claims priority under 35 U.S.C. §119(e) of U.S. Provisional patent application Ser. No. 60/612,656, entitled “Shaving Implement Employing Discrete Cartridge Sections,” filed on Sep. 24, 2004. The disclosure of this patent application is incorporated by reference herein in its entirety.
FIELD OF THE INVENTION
[0002] The present invention relates generally to wet shave razors and, more particularly, to a razor cartridge incorporating discrete independently moveable cartridge segments.
BACKGROUND OF THE INVENTION
[0003] Wet shave razors have historically incorporated razor cartridges that employ one or more elongated razor blades located therein. Often these razor cartridges pivot relative to a handle to which they are coupled to allow cutting edges defined by the razor blades to more closely follow the contours of a surface to be shaved. However, due to the elongated nature of the cutting edges, as well as the often complex contours of the surface being shaved, the pivoting of the razor cartridge is sometimes not adequate to provide for conformity of the razor blades to the skin surface.
[0004] Based on the foregoing, it is the general object of the present invention to provide a razor cartridge and/or wet shave razor that improves upon or overcomes the inability of prior art razors to precisely follow the contours of a surface to be shaved during a shaving operation.
SUMMARY OF THE INVENTION
[0005] The present invention resides in one aspect in a razor cartridge having a frame and at least two discrete cartridge segments positioned therein and moveable relative thereto. Each of the cartridge segments includes at least one razor blade having an at least partially exposed cutting edge. Preferably, the razor cartridge includes a plurality of discrete cartridge segments each positioned in, and independently movable relative to the frame.
[0006] Biasing means are positioned in the frame and are in communication with each of the cartridge segments for normally urging the cartridge segments and razor assemblies disposed therein in a direction towards the surface to be shaved (a neutral position) in response to forces exerted against the cartridge segments during a shaving operation. In one embodiment of the present invention, the biasing means take the form of cantilevered spring members, each having one end resiliently coupled to the frame and a generally opposite cantilevered end engageable with an underside of one of the cartridge segments. The cantilevered spring members normally urge the cartridge segments with which they are engaged, toward the neutral position. While a cantilevered spring has been described, the present invention is not limited in this regard as other forms of biasing means known to those skilled in the pertinent art to which the present invention pertains, such as, for example, coil springs, leaf-type springs, and resilient materials such as, for example, foam, which can be substituted without departing from the broader aspects of the present invention.
[0007] In one embodiment, each of the cartridge segments includes a housing and two razor blade assemblies positioned in the housing. Each razor blade assembly includes a razor blade having an at least partially exposed cutting edge. The cartridge segments can be positioned in the frame in rows that are substantially parallel to one another, with the same or different numbers of cartridge segments in each row. In one embodiment, the cartridge segments can be positioned in the frame in arcuate, circular, or other nesting patterns. While the cartridge segments have been illustrated as including two razor blade assemblies per segment, the present invention is not limited in this regard as less than or more than two razor blade assemblies can be employed in each cartridge segment.
[0008] In another embodiment of the present invention, the cartridge segments can be positioned in the frame so that the cutting edges of the razor blades positioned in the razor blade assemblies in some of the cartridge segments generally face away from the cutting edges of the razor blades of the remaining cartridge segments. With the cartridge segments configured in this manner, the razor cartridge can cut hair when moved over a surface to be shaved in either of two generally opposite directions.
[0009] Similarly, one portion of the cartridge segments can be positioned in the frame so that the cutting edges of some of the blades located therein generally face toward the cutting edges of the blades positioned in the remainder of the cartridge segments. This configuration also allows the razor cartridge to cut hair when moved over a surface to be shaved in either of two generally opposite directions.
[0010] In one embodiment, the present invention includes a wet shave razor incorporating the above-described razor cartridge either permanently or releasably mounted onto a razor handle.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is a top view of a razor cartridge configured in accordance with the present invention.
[0012] FIG. 2 is a front view of the razor cartridge of FIG. 1 .
[0013] FIG. 3 is a side view of the razor cartridge of FIG. 1 .
[0014] FIG. 4 is a perspective view of a cartridge segment configured in accordance with the present invention.
[0015] FIG. 5 is a cross-sectional view of a razor blade assembly forming part of a cartridge segment.
[0016] FIG. 6 is a front view of the razor blade assembly of FIG. 5 .
[0017] FIG. 7 is a bottom view of the razor blade assembly of FIG. 5 .
[0018] FIG. 8 is a perspective view of a frame forming part of the razor cartridge of FIG. 1 , showing a plurality of cantilevered springs and resilient retaining members.
[0019] FIG. 9 is a cross-sectional view of the razor cartridge of FIG. 1 taken along line 9 - 9 through the center of the razor cartridge. The cartridge segments beings positioned in two successive rows with the cartridge segments being staggered so that line 9 - 9 bisects one cartridge segment in one row and is positioned between adjacent cartridge segments in the other row.
[0020] FIG. 10 is a cross-sectional view of the razor cartridge of FIG. 1 taken along line 10 - 10 and shows the manner by which the cartridge segments engage the frame.
[0021] FIG. 11 is a cross-sectional view of the razor cartridge of FIG. 1 taken along line 11 - 11 which extends through one of the cartridge segments and through an end portion of the frame.
[0022] FIGS. 12, 12 a , and 12 b are top views of embodiments of the razor cartridge of the present invention showing cartridge segments positioned in an arcuate pattern.
[0023] FIG. 13 is a cross-sectional view of a pair of razor cartridge segments positioned relative to one another so that the razor blades carried by one cartridge segment face away from the razor blades carried by the other cartridge segment thereby illustrating how these cartridge segments would be positioned relative to one another in a razor cartridge to facilitate bi-directional shaving.
[0024] FIG. 14 is a cross-sectional view of a pair of cartridge segments positioned relative to one another so that the razor blades carried by one cartridge segment face toward the razor blades carried by the other cartridge segment thereby illustrating how these cartridge segments would be positioned relative to one another in a razor cartridge to facilitate bidirectional shaving.
[0025] FIG. 15 is a top view of a wet shave razor incorporating the razor cartridge as illustrated in FIG. 1 .
[0026] FIG. 16 is a rear view of a wet shave razor incorporating the razor cartridge as illustrated in FIG. 1 .
[0027] FIG. 17 is a side view of a wet shave razor incorporating the razor cartridge as illustrated in FIG. 1 .
[0028] FIG. 18 shows a razor cartridge segment having wire wrapped cartridge segments.
[0029] FIG. 19 is a top view of an embodiment of a razor cartridge of the present invention showing a plurality of cartridge segments positioned adjacent a single longitudinally extending razor blade.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0030] As shown in FIG. 1 , a razor cartridge generally designated by the reference number 20 , includes a frame 22 and a plurality of discrete cartridge segments, generally designated by the reference number 24 , coupled thereto. As will be explained in detail below, the cartridge segments 24 are coupled to the frame 22 and are each independently moveable relative thereto. In one embodiment, illustrated in FIG. 4 , each cartridge segment 24 includes a housing 26 with two razor blade assemblies 28 positioned therein. Each of the razor blade assemblies 28 includes a razor blade 31 having an exposed cutting edge 33 . In accordance with one aspect of the invention, a length of the exposed cutting edge 33 of each of the razor blades 31 is a relatively shorter dimension than a length of exposed cutting edges of conventional blades assemblies. For example, exposed cutting edges of conventional razor blades extend over substantially all of the elongated length of a conventional cartridge frame. The Inventors have discovered that a wet shave razor employing a razor cartridge including a combination of shorter length cutting edges and discrete, independently moveable cartridge segments allows the razor cartridge to more closely follow contours of a surface to be shaved.
[0031] As shown in FIG. 4 , the cartridge segments 24 include a pair of end caps 29 one attached to each end of the housing 26 . Each end cap 29 is positioned over a portion of each of the razor blade assemblies 28 to aid in retaining the razor blade assemblies in the housing 26 . While the cartridge segments 24 have been shown and described as including two razor blade assemblies 28 , the present invention is not limited in this regard as more or less than two razor blade assemblies can be positioned in the housing 26 without departing from the broader aspects of the present invention.
[0032] As shown in FIGS. 5-7 , each razor blade assembly 28 includes a stiffener 30 and a razor blade 31 attached to the stiffener 30 . Each stiffener 30 defines a pair of apertures 32 located adjacent to the razor blade 31 to allow for a wash through of shaving debris during a shaving operation. Referring to FIGS. 9-11 , the razor blade assemblies 28 are positioned in the cartridge segments 24 , with the stiffeners 30 located so as to desirably orient the razor blades 31 relative to the frame 22 as well as to a surface to be shaved during a shaving operation.
[0033] As shown in FIG. 8 , the frame 22 includes a plurality of cantilevered spring members 32 , each cantilevered spring member 32 having one end 34 resiliently integral with the frame 22 and a generally opposite cantilevered end 36 . As will be explained in detail below, each cantilevered end 36 is engageable with an underside, shown generally at 35 , of one of the cartridge segments 24 and moveably supports the one respective cartridge segment 24 . Referring to FIGS. 9-11 during a shaving operation a pair of the cantilevered spring members 32 is positioned adjacent the underside 35 of each cartridge segment 24 with the cantilevered ends 36 of each spring member 32 abutting an end of the underside 35 of the cartridge segment 24 .
[0034] During a shaving operation, each cartridge segment 24 is independently moveable relative to the frame 22 and is normally urged, by the cantilevered spring members 32 , in an upward direction (indicated by arrow “A” of FIG. 9 ) towards a surface to be shaved into an upper-most or neutral position. While the frame 22 and spring members 32 have been shown and described as being integral with one another, the present invention is not limited in this regard as the spring members and the frame can also be distinct from one another without departing from the broader aspects of the present invention.
[0035] Referring back to FIG. 8 , the frame 22 includes resilient retaining members 40 each of which define stand-off portions 41 that extend outwardly from the frame 22 . The cartridge segments 24 are each movably retained on the frame 22 by abutment surfaces 38 at an underside of the resilient retaining members 40 . During assembly of the razor cartridge 20 , each cartridge segment 24 is slid over four retaining members 40 , one proximate each corner of the cartridge segment 24 . As the cartridge segments 24 are slid over the resilient retaining members 40 , the stand off portions 41 of the resilient retaining members 40 deform allowing a portion of the cartridge segment 24 to slide past the abutment surfaces 38 and engage a pair of the cantilevered spring elements 32 . Once a lip portion 42 defined by the housing 26 clears the abutment surfaces 38 the retaining members 40 move into an undeformed state so that the cartridge segment 24 can move (e.g., vertical translation) relative to the retaining member 40 until the lip portion 42 of the housing 26 engages the abutment surface 38 of the retaining member 40 . The position of the cartridge segments 24 when the lip portion 42 is engaged with the abutment surfaces 38 is defined herein as the aforementioned upper-most or neutral position of the cartridge segment 24 .
[0036] As shown in FIGS. 1-3 , and 9 - 11 , the razor cartridge 20 includes a guard bar 44 coupled to the frame 22 adjacent a leading edge thereof, for stretching a surface to be shaved (e.g., a user's skin), during a shaving operation, prior to the surface contacting the cutting edges 33 of the razor blades 31 . In one embodiment, the guard bar 44 is made of the same or a different material as the frame 22 . In another embodiment, the guard bar 44 employs a smooth or an uneven skin contacting surface. In yet another embodiment, the guard bar 44 incorporates a shaving aid, such as, but not limited to, an oil, a gel, medicaments, or lotion. In still another embodiment, the guard bar 44 is formed from a reduced friction material. A guard bar configured as illustrated above, is generally referred to by those skilled in the pertinent art to which the present invention pertains as a “glide strip.”
[0037] Still referring to FIGS. 1-3 , and 9 - 11 , the frame 22 includes a cap portion 46 having a comfort strip 48 coupled thereto. While the present invention has been shown and described as including a single comfort strip, the present invention is not limited in this regard as more than one comfort strip can be incorporated into the razor cartridge without departing from the broader aspects of the present invention. In one embodiment, a comfort strip is located in close proximity to each of the cartridge segments 24 , for example, on a surface of the frame 22 behind the cutting edges 33 of each razor blade 31 .
[0038] Referring back to FIG. 1 the illustrated embodiment of the razor cartridge 20 includes five cartridge segments 24 positioned in the frame 22 in two substantially parallel rows, one row containing two cartridge segments and another row containing three cartridge segments. However, it should be appreciated that the present invention is not limited in this regard as any number of rows, each containing the same or different numbers of cartridge segments 24 can be employed. Moreover, while the cartridge segments 24 have been shown and described as being positioned in the frame 22 in substantially parallel rows, the present invention is not limited in this regard as other configurations such as arcuate or circular rows can also be used. For example, as shown in FIGS. 12, 12 a , and 12 b the cartridge segments 24 are positioned in circular and arcuate patterns in the frame 22 . With respect to FIG. 12 , the cartridge segments 24 are illustrated so that the cutting edges 33 of the razor blades 31 generally face inwardly toward one another. In another embodiment, the cartridge segments 24 are positioned so that the cutting edges 33 of the razor blades 31 face outwardly. Moreover, while FIGS. 12 a and 12 b show specific arcuate cartridge segment nesting patterns, it should be appreciated that the present invention is not limited in this regard as any number of different arcuate nesting patterns can be employed without departing from the present invention.
[0039] As shown in FIG. 13 , the cartridge segments 24 can be arranged relative to one another in successive rows so that the cutting edges 33 of the razor blades 31 of the cartridge segments 24 positioned in one row face away from the cutting edges 33 of the razor blades 31 in an adjacent row thus allowing the razor cartridge 20 to cut hair when drawn over a user's skin in either of two generally opposite directions. While the illustrated embodiment shows the cutting edges 33 of the razor blades 31 carried by cartridge segments 24 in adjacent rows facing away from another to facilitate bi-directional shaving, the present invention is not limited in this regard.
[0040] As shown in FIG. 14 , the cartridge segments 24 can be positioned in successive rows such that the cutting edges 33 of the razor blades 31 positioned in the cartridge segments in one row generally face towards the cutting edges 33 of the razor blades 31 positioned in the cartridge segments 24 in the adjacent row. This embodiment also facilitates bi-directional shaving. While the cartridge segments 24 shown in FIGS. 13 and 14 illustrate the positioning of the cartridge segments for bi-directional shaving in a razor cartridge 20 having only two rows of cartridge segments, it should be appreciated that the present invention is not limited in this regard as any number of rows of cartridge segments can be employed in a razor cartridge without departing from the broader aspects of the present invention.
[0041] As shown in FIGS. 15-17 , the above described razor cartridge 20 can be attached, either permanently or releasably to a handle 50 . The razor cartridge 20 can pivot relative to the handle 50 as indicated by the arrows labeled “B.” However, the present invention is not limited in this regard as razor cartridge can also be non-rotatable relative to the handle.
[0042] As shown in FIG. 18 , the cartridge segments 24 include guard elements 52 which in the illustrated embodiment comprise wire, wrapped around the razor blades 31 to prevent excessive extrusion of a user's skin between the blades during a shaving operation. While wire wrapped razor blades have been shown and described, the present invention is not limited in this regard as other guard elements, such as, protuberances between the blades, can be substituted.
[0043] Turning to FIG. 19 , the razor cartridge 20 includes a plurality of discrete cartridge segments 24 positioned in adjacent rows. An elongated razor blade 54 is positioned between a cap portion of the razor cartridge 20 and the plurality of cartridge segments 24 . As shown in FIG. 19 , the razor blade 54 includes an elongated cutting edge 56 of a length L 3 that is of a relatively longer dimension than the length L 2 of the cutting edges 33 of the razor blades 31 of each of the discrete razor cartridge segments 24 . While a single elongated razor blade 54 has been shown in the illustrated embodiment, the present invention is not limited in this regard as more than one elongated razor blade can be employed without departing from the broader aspects of the present invention. Moreover, while the elongated razor blade 52 has been shown positioned adjacent to the cap portion of the razor cartridge, the present invention is not limited in this regard as the elongated razor blade can be positioned in other locations on the cartridge. For example, the elongated razor blade 54 can also be positioned adjacent to the guard portion 44 of the razor cartridge 20 or between adjacent rows of cartridge segments 24 .
[0044] While preferred embodiments have been shown and described, various modifications and substitutions may be made without departing from the scope of the present invention. Accordingly, it is to be understood that the present invention has been described by way of example, and not by limitation. | In a razor cartridge a frame is provided and carries at least two discrete cartridge segments each positioned in the frame for individual movement relative thereto. Each of the cartridge segments includes at least one razor blade that defines an at least partially exposed cutting edge. | 1 |
FIELD OF INVENTION
[0001] The present invention relates to a method for manufacturing an optical interference display. More particularly, the present invention relates to a method for manufacturing an optical interference display with posts of arms.
BACKGROUND OF THE INVENTION
[0002] Planar displays are popular for portable displays and displays with space limits because they are light and small in size. To date, planar displays in addition to liquid crystal displays (LCD), organic electro-luminescent displays (OLED), plasma display panels (PDP) and so on, as well as a mode of the optical interference display are of interest.
[0003] U.S. Pat. No. 5,835,255 discloses an array of display units of visible light that can be used in a planar display. Please refer to FIG. 1, which depicts a cross-sectional view of a display unit in the prior art. Every optical interference display unit 100 comprises two walls, 102 and 104 . Posts 106 support these two walls 102 and 104 , and a cavity 108 is subsequently formed. The distance between these two walls 102 and 104 , that is, the length of the cavity 108 , is D. One of the walls 102 and 104 is a semi-transmissible/semi-reflective layer with an absorption rate that partially absorbs visible light, and the other is a light reflective layer that is deformable when voltage is applied. When the incident light passes through the wall 102 or 104 and arrives in the cavity 108 , in all visible light spectra, only the visible light with the wavelength corresponding to the formula 1.1 can generate a constructive interference and can be emitted, that is,
2D=Nλ (1.1)
[0004] where N is a natural number.
[0005] When the length D of cavity 108 is equal to half of the wavelength times any natural number, a constructive interference is generated and a sharp light wave is emitted. In the meantime, if the observer follows the direction of the incident light, a reflected light with wavelength λ 1 can be observed. Therefore, the display unit 100 is “open”.
[0006] The first wall 102 is a semi-transmissible/semi-reflective electrode that comprises a substrate, an absorption layer, and a dielectric layer. Incident light passing through the first wall 102 is partially absorbed by the absorption layer. The substrate is made from conductive and transparent materials, such as ITO glass or IZO glass. The absorption layer is made from metal, such as aluminum, chromium or silver and so on. The dielectric layer is made from silicon oxide, silicon nitrite or metal oxide. Metal oxide can be obtained by directly oxidizing a portion of the absorption layer. The second wall 104 is a deformable reflective electrode. It shifts up and down by applying a voltage. The second wall 104 is typically made from dielectric materials/conductive transparent materials, or metal/conductive transparent materials.
[0007] [0007]FIG. 2 depicts a cross-sectional view of a display unit in the prior art after applying a voltage. As shown in FIG. 2, while driven by the voltage, the wall 104 is deformed and falls down towards the wall 102 due to the attraction of static electricity. At this time, the distance between wall 102 and 104 , that is, the length of the cavity 108 is not exactly zero, but is d, which can be zero. If we use d instead of D in formula 1 . 1 , only the visible light with a wavelength satisfying formula 1.1, which is λ 2 , can generate a constructive interference, and be reflected by the wall 104 , and pass through the wall 102 . Because wall 102 has a high light absorption rate for light with wavelength λ 2 , all the incident light in the visible light spectrum is filtered out and an observer who follows the direction of the incident light cannot observe any reflected light in the visible light spectrum. The display unit 100 is now “closed”.
[0008] Refer to FIG. 1 again, which shows that the posts 106 of the display unit 100 are generally made from negative photoresist materials. Refer to FIGS. 3A to 3 C, which depict a method for manufacturing a display unit in the prior art. Referring to FIG. 3A, the first wall 102 and a sacrificial layer 110 are formed in order on a transparent substrate 109 , and then an opening 112 is formed in the wall 102 and the sacrificial layer 110 . The opening 112 is suitable for forming posts therein. Next, a negative photoresist layer 111 is spin-coated on the sacrificial layer 110 and fills the opening 112 . The objective of forming the negative photoresist layer 111 is to form posts between the first wall 102 and the second wall (not shown). A backside exposure process is performed on the negative photoresist layer 111 in the opening 112 , in the direction indicated by arrow 113 to the transparent substrate 109 . The sacrificial layer 110 must be made from opaque materials, typically metal materials, to meet the needs of the backside exposure process.
[0009] Refer to FIG. 3B, which shows that posts 106 remain in the opening 112 after removing the unexposed negative photoresist layer. Then, the wall 104 is formed on the sacrificial layer 110 and posts 106 . Referring to FIG. 3C, the sacrificial layer 110 is removed by a release etch process to form a cavity 114 . The length D of the cavity 114 is the thickness of the sacrificial layer 110 . Therefore, different thicknesses of the sacrificial layers must be used in different processes of the different display units to control reflection of light with different wavelengths.
[0010] An array comprising the display unit 100 controlled by voltage operation is sufficient for a single color planar display, but not for a color planar display. A method in the prior art is to manufacture a pixel that comprises three display units with different cavity lengths as shown in FIG. 4, which depicts a cross-sectional view of a matrix color planar display in the prior art. Three display units 302 , 304 and 306 are formed as an array on a substrate 300 , respectively. Display units 302 , 304 and 306 can reflect an incident light 308 to color lights with different wavelengths, for example, which are red, green and blue lights, due to the different lengths of the cavities of the display units 302 , 304 and 306 . It is not required that different reflective mirrors be used for the display units arranged in the array. More important is that good resolution be provided and the brightness of all color lights is uniform. However, three display units with different lengths of cavities need to be manufactured separately.
[0011] Please refer to FIGS. 5A to 5 D, which depict cross-sectional views of a method for manufacturing the matrix color planar display in the prior art. In FIG. 5A, the first wall 310 and the first sacrificial layer 312 are formed in order on a transparent substrate 300 , and then openings 314 , 316 , 318 , and 320 are formed in the first wall 310 and the sacrificial layer 312 for defining predetermined positions where display units 302 , 304 , and 306 are formed. The second sacrificial layer 322 is then conformally formed on the first sacrificial layer 312 and in the openings 314 , 316 , 318 , and 320 .
[0012] Please referring to FIG. 5B, after the second sacrificial layer 322 in and between the openings 314 and 316 , and in the openings 318 and 320 is removed by a photolithographic etch process, the third sacrificial layer 324 is conformally formed on the first sacrificial layer 312 and the second sacrificial layer 322 and in the openings 314 , 316 , 318 and 320 .
[0013] Please refer to FIG. 5C, which shows that the third sacrificial layer 324 in the openings 318 and 320 remains but the remainder of the third sacrificial layer 324 is removed by a photolithographic etch process. Next, a negative photoresist is spin-coated on the first sacrificial layer 312 , the second sacrificial layer 322 , and the third sacrificial layer 324 , and in the openings 314 , 316 , 318 and 320 , and fills the all openings to form a negative photoresist layer 326 . The negative photoresist layer 326 is used for forming posts (not shown) between the first wall 310 and the second wall (not shown).
[0014] Please refer to FIG. 5D, which shows that a backside exposure process is performed on the negative photoresist layer 326 in the openings 314 , 316 , 318 and 320 in a direction of the transparent substrate 300 . The sacrificial layer 110 must be made at least from opaque materials, typically metal materials, to meet the needs of the backside exposure process. Posts 328 remain in the openings 314 , 316 , 318 and 320 after removing the unexposed negative photoresist layer 326 . Subsequently, the second wall 330 conformally covers the first sacrificial layer 312 , the second sacrificial layer 322 , the third sacrificial layer 324 and posts 328 .
[0015] Afterward, the first sacrificial layer 312 , the second sacrificial layer 322 , and the third sacrificial layer 324 are removed by a release etch process to form the display units 302 , 304 , and 306 shown in FIG. 4, wherein the lengths d1, d2, and d3 of three display units 302 , 304 , and 306 are the thicknesses of the first sacrificial layer 312 , the second sacrificial layer 322 , and the third sacrificial layer 324 , respectively. Therefore, different thicknesses of sacrificial layers must be used in different processes of the different display units, to achieve the objective for controlling reflection of different wavelengths of light.
[0016] There are at least three photolithographic etch processes required for manufacturing the matrix color planar display in the prior art, to define the lengths of the cavities of the display units 302 , 304 , and 306 . In order to cooperate with the backside exposure for forming posts, metal materials must be used for making the sacrificial layer. The cost of the complicated manufacturing process is higher, and the yield cannot be increased due to the complicated manufacturing process.
[0017] Therefore, it is an important subject to provide a simple method of manufacturing an optical interference display unit structure, for manufacturing a color optical interference display with high resolution, high brightness, simple process and high yield.
SUMMARY OF THE INVENTION
[0018] It is therefore an objective of the present invention to provide a method for manufacturing an optical interference display unit structure, and the method is suitable for manufacturing a color optical interference display with resolution and high brightness.
[0019] It is another an objective of the present invention to provide a method for manufacturing an optical interference display unit structure, and the method is suitable for manufacturing a color optical interference display with a simple and easy manufacturing process and high yield.
[0020] It is still another objective of the present invention to provide a method for manufacturing an optical interference display unit structure, and the method is suitable for manufacturing a color optical interference display with posts.
[0021] In accordance with the foregoing objectives of the present invention, one preferred embodiment of the invention provides a method for manufacturing an optical interference display unit structure. The first wall and a sacrificial layer are formed in order on a transparent substrate, and then an opening is formed in the first wall and the sacrificial layer. The opening is suitable for forming posts therein. Next, a photoresist layer is spin-coated on the sacrificial layer and fills the opening. A photolithographic process patterns the photoresist layer to define a support with an arm. The support and the arm are used for a post, and to define the length of the arm. Due to the exposure of the photoresist layer with the help of a mask, the sacrificial layer no longer must be opaque materials such as metal and the like; common dielectric materials are also used for making the sacrificial layer.
[0022] The second wall is formed on the sacrificial layer and posts, and then baking is performed on the posts. The arm may generate displacement as the pivot of the support caused by stress action. An end of the arm adjacent to the support has less displacement, but another end of the arm has more displacement. The displacement of the arm may change the position of the second wall. Afterward, the sacrificial layer is removed by a release etch process to form a cavity, and the length D of the cavity may not be equal to the thickness of the sacrificial layer due to the displacement of the arm.
[0023] The arms with the ratios of various lengths to thicknesses have various amounts of stress, and displacements and directions generated by arms are various during baking. Therefore, the arms with the ratios of various lengths to thicknesses may be used for controlling the length of the cavity, instead of the various thicknesses of the sacrificial layers used in the various processes of the display units to control various wavelengths of light reflected in the prior art. There are many advantages in the above way. First of all, the cost drops drastically. The thickness of the cavity in the prior art is the thickness of the sacrificial layer, and the sacrificial layer needs to be removed at the end of the process. However, using an upward displacement of the arms in the present invention increases the length of the cavity, so that the length of the cavity is greater than the thickness of the sacrificial layer, even if the thickness of the sacrificial layer is substantially decreased while forming the same length of cavities. Therefore, the material used for manufacturing the sacrificial layer is substantially reduced. The second, the process time is shortened. The release etch process of the metal sacrificial layer in the prior art consumes lots of time, because the sacrificial layer is removed by an etching gas that must permeate the spaces between the posts. The present invention utilizes a mask for a front exposure, so the sacrificial layer can be transparent materials such as dielectric materials, instead of opaque materials such as metal and the like as in the prior art. Besides, the thickness used by the sacrificial layer can be substantially reduced, so the time required for the release etch process can be also drastically decreased. Third, the color optical interference display formed by using posts can substantially reduce complexity of the process. The difference in the ratios of lengths to thicknesses of arms of posts is used for changing the stress of the arms. After baking, various optical interference display units have various lengths of the cavities due to the displacement of arms, such that reflected light is changed with various wavelengths, such as red, green, and blue lights, so as to obtain various color lights.
[0024] In accordance with another an objective of the present invention, one preferred embodiment of the invention provides a method for manufacturing a matrix color planar display structure. Each matrix color planar display unit has three optical interference display units. The first wall and a sacrificial layer are formed in order on a transparent substrate, and then an opening is formed in the first wall and the sacrificial layer. The opening is suitable for forming posts therein. Next, a photoresist layer is spin-coated on the sacrificial layer and fills the opening. A photolithographic process patterns the photoresist layer to define a support with an arm. The support and the arm are used for a post, and to define the length of the arm. A single photolithographic process can accomplish the arms of three optical interference display units. Due to the exposure of the photoresist layer with the help of a mask, the sacrificial layer no longer must be an opaque material such as metal and the like; common dielectric materials are also used for making the sacrificial layer.
[0025] The second wall is formed on the sacrificial layer and posts, and then baking is performed on the posts. The arm may generate displacement as the pivot of the support caused by stress action. An end of the arm adjacent to the support has less displacement, but another end of the arm has more displacement. The displacement of the arm may change the position of the second wall. Afterward, the sacrificial layer are removed by a release etching process to form a cavity, and the length D of the cavity may not be equal to the thickness of the sacrificial layer due to the displacement of the arm.
[0026] The first wall is the first electrode, and the second wall is the second electrode. Each T-shaped arm of the optical interference display unit has variable length and stress. Therefore, after baking, each optical interference display unit has various cavity lengths due to the various displacements of arms, such that reflected light is changed with different wavelengths, such as red, green, and blue light. These in turn provide various color lights for a matrix color planar display structure.
[0027] In accordance with the color planar display consisting of an array of optical interference display units disclosed by the present invention, the advantages of a matrix color planar display according to the prior art are retained, including high resolution and high brightness, as well as the advantages of a multi-layered color planar display with a simple process and high yield in the prior art. It is understood that the present invention discloses an optical interference display unit which not only keeps all advantages of the prior optical interference color planar display such as high resolution, high brightness, simple process and high yield during forming arrays, but also increases the window during processing and raises the yield of the optical interference color planar display.
[0028] It is to be understood that both the foregoing general description and the following detailed description are examples, and are intended to provide further explanation of the invention as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0029] These and other features, aspects, and advantages of the present invention will be more fully understood by reading the following detailed description of the preferred embodiment, with reference made to the accompanying drawings as follows:
[0030] [0030]FIG. 1 depicts a cross-sectional view of a display unit in the prior art;
[0031] [0031]FIG. 2 depicts a cross-sectional view of a display unit in the prior art after applying a voltage;
[0032] [0032]FIGS. 3A to 3 C depict a method for manufacturing a display unit in the prior art;
[0033] [0033]FIG. 4 depicts a cross-sectional view of a matrix color planar display in the prior art;
[0034] [0034]FIGS. 5A to 5 D depict cross-sectional views of a method of manufacturing a matrix color planar display in the prior art;
[0035] [0035]FIGS. 6A to 6 C depict a method for manufacturing an optical interference display unit according to one preferred embodiment of this invention;
[0036] [0036]FIG. 6D depicts a cross-sectional view of an optical interference display unit according to one preferred embodiment of this invention; and
[0037] [0037]FIGS. 7A to 7 D depict a method of manufacturing a matrix color planar display structure according to the second preferred embodiment of this invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0038] In order to provide more information of the optical interference display unit structure, the first embodiment is provided herein to explain the optical interference display unit structure in this invention. In addition, the second embodiment is provided to give further description of the optical interference color planar display formed with an array of the optical interference display unit.
[0039] Embodiment 1
[0040] [0040]FIGS. 6A to 6 C depict a method for manufacturing an optical interference display unit according to a preferred embodiment of the invention. Please referring to FIG. 6A first, a first electrode 502 and a sacrificial layer 506 are formed in order on a transparent substrate 501 . The sacrificial layer 506 is made of transparent materials such as dielectric materials, or opaque materials such as metal materials. An opening 508 is formed in the first electrode 502 and the sacrificial layer 506 by a photolithographic etch process. The opening 508 is suitable for forming a post therein.
[0041] Next, a material layer 510 is formed in the sacrificial layer 506 and fills the opening 508 . The material layer 510 is suitable for forming posts, and the material layer 510 generally uses photosensitive materials such as photoresists, or non-photosensitive polymer materials such as polyester, polyamide or the like. If non-photosensitive materials are used for forming the material layer 510 , a photolithographic etch process is required to define posts in the material layer 510 . In this embodiment, the photosensitive materials are used for forming the material layer 510 , so merely a photolithographic etching process is required for patterning the material layer 510 .
[0042] Please referring to FIG. 6B, the posts 512 are defined by patterning the material layer 510 during a photolithographic process. The post 512 has a support 514 disposed in the opening 508 , and the post 512 has arms 5121 and 5122 . The same photolithographic process also defines the lengths of arms 5121 and 5122 . The thicknesses of the arms 5121 and 5122 are decided in the step of forming the material layer 510 . A second electrode 504 is formed on the sacrificial layer 506 and the post 512 .
[0043] Reference is next made to FIG. 6C. A thermal process is performed, such as baking. Arms 5121 and 5122 of the post 512 may generate displacement as the pivot of the support 514 caused by stress action. Ends of the arms 5121 and 5122 adjacent to the support 514 have less displacement, but other ends of the arms 5121 and 5122 have more displacement. The displacement of arms 5121 and 5122 may change the position of the second electrode 504 . Thereafter, the sacrificial layer 506 is removed by a release etch process to form a cavity 516 .
[0044] The optical interference display unit made in FIGS. 6A to 6 C is shown in FIG. 6D, which depicts a cross-sectional view of an optical interference display unit of one preferred embodiment of this invention. An optical interference display unit 500 , which may be a color changeable pixel unit, at least comprises a first electrode 502 and a second electrode 504 . The first electrode 502 and the second electrode 504 are approximately parallel to each other. The first electrode 502 and the second electrode 504 are selected from the group consisting of narrowband mirrors, broadband mirrors, non-metal mirrors or the combination thereof.
[0045] Posts 512 support the first electrode 502 and the second electrode 504 . The arms 5121 and 5122 of the posts 512 are raised upwards. The length of the cavity is the thickness of the sacrificial layer in the optical interference display unit structure in the prior art. If the thickness of the sacrificial layer is D, the length of the cavity is D, too. In this embodiment, a cavity 516 is formed between the first electrode 502 and the second electrode 504 supported by posts 512 . The posts 512 have the arms 5121 and 5122 . The ratio of lengths to thicknesses of the arms 5121 and 5122 decide stress thereof, and a dotted line 5121 ′ and a dotted line 5122 ′ label the positions prior to performing a thermal process of the arms 5121 and 5122 . After performing the thermal process, the arms 5121 and 5122 may generate displacement; therefore the position of the second electrode 504 changes from the original position labeled by the dotted line 504 ′, and the length D′ of the cavity 516 between the first electrode 502 and the second electrode 504 changes from the original length D. Since the length of the cavity 516 changes, the frequency of a reflected light changes following the length of the cavity 516 . In general, when posts 512 are made from polyamide compounds, the ratio of lengths to thicknesses of the arms 5121 and 5122 is from 5 to 50, and the length D′ of the cavity 516 is approximately 1.5 to 3 times the length D of the thickness of the sacrificial layer. Of course, the ratio of lengths to thicknesses of the arms 5121 and 5122 can be changed to make the length D′ of the baked cavity 516 smaller than the thickness of the sacrificial layer.
[0046] In this invention, the materials suitable for forming posts 512 include positive photoresists, negative photoresists, and all kinds of polymers such as acrylic resins, epoxy resins and so on.
[0047] Embodiment 2
[0048] [0048]FIGS. 7A to 7 D depict a method for manufacturing a matrix color planar display structure according to the second preferred embodiment of this invention. Reference is made to FIG. 7A first, illustrating formation of the first electrode 602 and a sacrificial layer 604 in order on a transparent substrate 601 . The sacrificial layer 604 can be made of transparent materials such as dielectric materials, or opaque materials such as metal materials. Openings 606 , 608 , 610 , and 612 are formed in the first electrode 602 and the sacrificial layer 604 by a photolithographic etch process, and openings 606 , 608 , 610 , and 612 are suitable for forming posts therein.
[0049] Next, a material layer 614 is formed on the sacrificial layer 604 and fills the openings 606 , 608 , 610 , and 612 . The optical interference display unit 624 is defined by openings 606 and 608 , the optical interference display unit 626 is defined by openings 608 and 610 , and the optical interference display unit 628 is defined by openings 610 and 612 . The material layer 614 is suitable for forming posts, and is generally made from photosensitive materials such as polyester or non-photosensitive materials such as polyester, polyamide or the like. If a non-photosensitive material is used for forming the material layer 614 , a photolithographic etching process is required to define posts on the material layer 614 . In this embodiment, the photosensitive material is used for forming the material layer 614 , so a single photolithographic etch process is sufficient for patterning the material layer 614 .
[0050] Please refer to FIG. 7B. A photolithographic process patterns the first material layer 614 , so as to define posts 616 , 618 , 620 , and 622 . The posts 616 , 618 , 620 , and 622 have supports 6161 , 6181 , 6201 , and 6221 disposed in the openings 606 , 608 , 610 , and 612 , respectively. The posts 616 , 618 , 620 , and 622 also have arms 6162 , 6182 , 6183 , 6202 , 6203 , and 6222 . The arms 6162 , 6182 , 6183 , 6202 , 6203 , and 6222 are the same in length. A second electrode 630 is formed on the sacrificial layer 604 , posts 616 , 618 , 620 , and 622 .
[0051] Please refer to FIG. 7C. A thermal process is performed, such as baking. The arms 6162 , 6182 , 6183 , 6202 , 6203 , and 6222 of the posts 616 , 618 , 620 , and 622 may generate displacement as the pivot of the supports 6161 , 6181 , 6201 , and 6221 caused by stress action. There is less displacement at the ends of the arms 6162 , 6182 , 6183 , 6202 , 6203 , and 6222 adjacent to the supports 6161 , 6181 , 6201 , and 6221 , but more displacement at the other ends of the arms 6162 , 6182 , 6183 , 6202 , 6203 , and 6222 . The displacements of the arms 6162 and 6182 are the same, the displacements of the arms 6183 and 6202 are the same, and the displacements of the arms 6203 and 6222 are the same. But there are various displacements among three above pairs of the arms. Therefore, there are various changes in the positions of the second electrode 630 caused by the arms 6162 and 6182 , the arms 6183 and 6202 , and the arms 6203 and 6222 .
[0052] Thereafter, reference is made to FIG. 7D. The sacrificial layer 604 is removed by a release etch process to form the cavities 6241 , 6261 , and 6281 of the optical interference display units 624 , 626 , and 628 . The cavities 6241 , 6261 , and 6281 have various lengths d 1 , d 2 , and d 3 , respectively. When the optical interference display units 624 , 626 , and 628 are “open”, as shown as the formula 1.1, the design of lengths d 1 , d 2 , and d 3 of the cavities 6241 , 6261 , and 6281 can generate the reflected light with different wavelengths, such as red (R), green (G), or blue (B) light.
[0053] The lengths d 1 , d 2 , and d 3 of the cavities 6241 , 6261 , and 6281 are not decided by the thickness of the sacrificial layer, but by the lengths of the arms 6162 and 6182 , 6183 and 6202 , 6203 and 6222 , respectively. Therefore, the complicated photolithographic process of the prior art to define various lengths of the cavities forming various thicknesses of the sacrificial layers is unnecessary.
[0054] In accordance with the color planar display consisting of the array of optical interference display units disclosed by this embodiment, the advantages of a matrix color planar display in the prior art are retained, including high resolution and high brightness, as well as the advantages of the prior art multi-layered color planar display such as simple process and high yield. Compared with the matrix color planar display in the prior art, the embodiment discloses an optical interference display unit that does not require the complicated photolithographic process in the prior art to define various lengths of the cavities by forming various thicknesses of the sacrificial layers. The optical interference display unit thus has a simple process and high yield. Compared with the matrix color planar display in the prior art, the embodiment discloses an array of optical interference display units, in which all the optical interference display units that can generate reflected color light are located in the same plane. In other words, the incident light can reflect various color lights without passing through the multi-layered optical interference display unit; thus, the optical interference display unit has high resolution and high brightness. Furthermore, in the multi-layered optical interference display in the prior art, in order to make an incident light to pass through a former display unit and reach a latter display unit efficiently, and the result of light interference in the latter display unit (reflected light of green or blue light wavelength) to pass through a former display unit efficiently, the compositions and thicknesses of the first electrode and the second electrode of three types of display units are different. The manufacturing process is actually more complicated than expected. The process for the array of the optical interference display units disclosed by this invention is less difficult than the process in the prior art.
[0055] Although the present invention has been described in considerable detail with reference certain preferred embodiments thereof, other embodiments are possible. Therefore, their spirit and scope of the appended claims should no be limited to the description of the preferred embodiments container herein. In view of the foregoing, it is intended that the present invention cover modifications and variations of this invention provided they fall within the scope of the following claims and their equivalents. | A method for fabricating an interference display unit is provided. A first plate and a sacrificial layer are formed in order on a substrate and at least two openings are formed in the first plate and the sacrificial layer. A photoresist layer is spin-coated on the sacrificial layer and fills the openings. A photolithographic process patterns the photoresist layer to define a support with an arm. A second plate is formed on the sacrificial layer and posts. The arm's stress is released through a thermal process. The position of the arm is shifted and the distance between the first plate and the second plate is therefore defined. Finally, The sacrificial layer is removed. | 1 |
TECHNICAL FIELD
This invention relates generally to controlling power to the subsystems of a construction machine and particularly to distributing available power to the machine subsystems by using a power management controller responding to predetermined priorities and operational requirements. In the example given, the invention relates to the implement and drive train subsystems of a construction machine.
BACKGROUND
In operating construction machinery the available power, typically provided by an internal combustion engine, is mainly consumed by three major systems; namely, a power steering system, an implement control system and a power train system for propulsion. For safety reasons, it is typical for the steering system to be given first priority to available power. The remaining power is available for consumption by the implement operating system and the power train system.
In operating a wheel loader to load rock in a raised hopper of a rock crusher, the wheel loader scoops up a bucket load of raw material and travels toward the hopper with the bucket relatively low in interest of visibility and machine stability. Although some rock crusher hoppers are located on level ground, it is common practice to build a loading ramp to the hopper, the length and grade of which varies from site to site. As the loader approaches the hopper, the operator raises the bucket in anticipation of dumping the load when the hopper is reached. Thus the implement operating system and the power train system are simultaneously consuming power.
In prior power management systems the implement operating system is given priority to the available power for the power train system; however, the available power for the power train may be so limited as to produce excessively slow travel speed when raising the bucket and traveling up a relatively steep loading ramp. Excessively slow speed reduces operating efficiency of the wheel loader. Control systems heretofore provided for construction machinery have not allocated power to implement and power train systems to ensure their simultaneous operation in an acceptable manner.
In U.S. Pat. No. 5,525,043 issued Jun. 11, 1996 to Michael S. Lukich for a Hydraulic Power Control System, a method and apparatus are described for controlling a hydraulic control system in a hydraulic excavator to limit engine lug. The displacement of a hydraulic pump driven by the engine is reduced in response to the engine load increasing above a predefined level to prevent the engine from stalling. This method and control apparatus would not provide satisfactory minimum/maximum allocation of power to implement and drive train systems such as used in wheel loaders.
U.S. Pat. No. 6,047,545 issued Apr. 11, 2000 to Horst Deininger for Hydrostatic Drive System discloses a lift truck power system in which a hydraulic steering system is given first priority, a hydraulic work system is given second priority and a hydrostatic drive system is given third priority. This and other priority systems employed in wheel loaders give rise to the problem of excessively slow travel speed when traveling with a load of rock up a loading ramp to a rock crusher hopper and simultaneously raising the bucket in anticipation of dumping the raw material in the hopper.
U.S. Pat. No. 5,295,353 issued Mar. 22, 1994 to M. Ikari for a Controlling Arrangement for Travelling Work Vehicle illustrates and describes a wheel loader having a torque converter and two fixed capacity hydraulic pumps supplying pressure fluid to the valves controlling boom lift and bucket tile actuators. One of the two hydraulic pumps is unloaded when the accelerator pedal is at full throttle and the engine speed is under a predetermined speed. Although this control system provides a change in allocation of power when the engine does not increase speeds in response to a requested speed increase, the control does not provide for adjustment of the power allocations to the implement and power train subsystems based on the operator's desired commands.
The present invention is directed to overcoming one or more of the problems as set forth above.
SUMMARY OF THE INVENTION
In one aspect of the present invention, the available power, after satisfying vehicle steering requirements, is allocated to an implement subsystem and power train system.
The allocation of power to the implement subsystem and the power train subsystem is controlled by a power management system which is programmed to allocate a quantity of available power to the implement subsystem, such quantity falling between predetermined maximum and minimum percentages of the available power depending on the difference between desired travel speed and actual travel speed.
The maximum and minimum percentages of the available power allocated to the implement subsystem may be adjusted to provide efficient machine performance for particular machine work assignments. Adjustable set points are preferably provided to establish the minimum difference between the desired and the actual travel speed at which the maximum percent of available power is allocated to the implement subsystem and to establish the maximum difference in the desired and the actual travel speed at which the minimum percent of available power is allocated to the implement subsystem. An on-board compute is programmed to provide a smooth change in power allocation to the implement subsystem as changes occur in the difference between requested travel speed and actual travel speed.
BRIEF DESCRIPTION OF THE DRAWINGS
An embodiment of the invention is illustrated in the accompanying drawings in which:
FIG. 1 is a side view of a wheeled Loader dumping raw material into a rock crusher hopper;
FIG. 2 is a diagram showing the flow of power from an engine to power consuming subsystems;
FIG. 3 is a diagram illustrating the basic allocation of power to two subsystems;
FIG. 4 is a diagram illustrating operation of a power management controller;
FIGS. 5, 6 , 7 , 8 and 9 are curves illustrating power allocation to the implement subsystem and
FIG. 10 is a block diagram illustrating the operation of a power management controller in an engine driven construction machine.
DETAILED DESCRIPTION
In FIG. 1 a wheel loader 11 is shown dumping rocks into a hopper 12 of a rock crusher. The wheel loader 11 is equipped with an internal combustion engine 13 which drives a pair of front wheels 14 , 16 and a pair of rear wheels 17 , 18 through a power train subsystem 19 which includes a transmission 20 . The engine 13 also drives a pump 21 supplying hydraulic power to a steering subsystem 22 which includes a steering cylinder 23 , and drives a variable displacement pump 24 supplying pressurized hydraulic fluid to implement lift and tilt valves, not shown, controlling a pair of cylinders 26 , 27 and a tilt cylinder 28 of an implement subsystem 29 .
When either of the control valves, not shown, for operating the lift and tilt cylinders 26 , 27 , 28 , are shifted to a cylinder actuating position the variable displacement pump 24 is automatically stroked from neutral to a pressure fluid supplying condition, the displacement adjustment being dependent on the extend of the adjustment of the implement valve or valves.
For safety reasons the steering subsystem is given first priority to engine power. The power left over, after satisfying the steering subsystem power requirements, is available for consumption by the implement and power train subsystems and is hereinafter referred to as calculated power available or available power.
Referring to FIG. 2, a power management controller 36 on board the wheel loader 11 calculates the available power after deducting steering power being consumed and makes an allocation of the calculated power available to the implement subsystem 29 . The remaining power is available for consumption by the power train subsystem 19 .
The power management controller 36 is fed a signal such as a number indicative of the rated horse power of the engine 13 and a steering power signal, such as a number, based on desired cylinder speeds and pump pressure, which permit the power management controller 36 to calculate the power available (PA) for distribution to the implement and power train subsystems 29 , 19 .
FIG. 3 shows the calculated power available divided between the implement and power train subsystems. The fractional allocation λ of available power to the implement subsystem 29 automatically determines the power allocation to the power train subsystem 19 , represented by 1-λ. Thus, represents the fraction of the available power allocated to the implement subsystem 29 and 1-λ designates the fraction of available power allocated to the power train subsystem 19 . Since the wheel loader 11 is equipped with a variable displacement pump 24 delivering pressurized fluid to the implement subsystem, the power management controller 36 allocates power by changing the amount of pressurized fluid flowing to the implement subsystem control valves, not shown. This is done by the power management controller 36 changing the displacement of the variable displacement pump 24 .
A power distribution algorithm is loaded into a computer in the power management controller 36 which programs the computer to cause the power management controller 36 to vary the allocation of power to the implement subsystem 29 in response to deficiencies in the actual travel speed as compared to the desired travel speed of the wheel loader. A signal indicative of the desired travel speed is delivered to the power management controller 36 by a sensor, not shown, associated with a speed control, not shown, operated by the machine operator. For instance the sensor could sense displacement of an acceleration pedal. An actual travel speed signal is delivered to the power management controller by a travel speed sensor associated with the power train subsystem 19 . The travel speed sensor may sense the speed of the output shaft of the transmission of the power train subsystem 19 , which is indicative of the actual travel speed of the wheel loader.
The operation of the power management controller 36 is illustrated in FIG. 4 . The power management controller 36 is only active when a power limited condition is determined by the transmission controller. In the event the wheel loader 11 is power limited, the power available (PA) for allocation is calculated. In addition, the value of λ and the operator's desired implement power are calculated by the power management controller 36 . The implement tilt and lift levers, not shown, associated with the operator's desired lift and tilt cylinder velocities delivers a signal to the power management controller 36 which is indicative of the desired power for the implement subsystem 29 . If the desired implement power is less than the power allocated to the implement subsystem 29 , then the power management controller 36 will not issue an implement subsystem power command. In other words, the power consumed by the implement subsystem 29 will only be reduced if the operator is demanding more power for this subsystem than the power distribution algorithm would allocate. If the operator is demanding more power for the implement subsystem 29 than is allocated to the implement subsystem 29 , the power management controller 36 (which changes the stroking of the variable displacement pump 29 ) will reduce the operator implement commands until the power consumed by the implement subsystem 29 is equal to the power allocated to that subsystem.
The power management controller 36 is programmed to provide power to the implement subsystem 29 between predetermined minimum (λmin) and maximum (λmax) fractions of the available power.
The program entered into the computer is the equation:
λ=λmin+(λmax−λmin)(1−3 x 2+2 x 3)
where
x=Abs(Requested-actual trans speed)−λmax setpoint
λmin setpoint−λmax setpoint
and Abs denotes that the difference in requested transmission speed and actual transmission speed is expressed as an absolute value. In other words, if the difference is a negative number, it is transformed to a positive number.
FIG. 5 shows λ as a function of the transmission speed error in accordance with the before mentioned equation. The λ as a function of the transmission speed error in accordance with the before mentioned equation. The λ scheduling function has three segments. The first segment extends from zero to a λmax setpoint. The second segment is a transition lying between the λmax setpoint and a λmin setpoint where the value of λ ranges from λmax to λmin. the second segment of the curve, a transition part, is represented by an equation:
λ=1−3 x 2+2 x 3
which is a simple third order polynomial not especially computationally demanding of the computer of the power management controller 36 . The third segment of the curve extends beyond the λmin setpoint where λ is a fixed value of λmin. As will be noted the third order polynomial expression, 1−3x2+2x3, is part of the equation for the curve of FIG. 5 and also the later discussed curves shown in FIGS. 6-9.
There are four parameters which define the λ scheduling function; (1) λmax, (2) λmin, (3) λmax setpoint, and (4) λmin setpoint. Each parameter has physical meaning and can be specified based on operator perception. The maximum value of λ, (λmax), represents the maximum fraction of power available to the implement subsystem. The parameter λmax also determines the minimum fraction of power available for the power train subsystem 19 . Furthermore, λmin represents the minimum fraction of power available for the implement subsystem 29 and determines the maximum fraction of power available for the power train subsystem 19 .
The values of the parameters entered into the computer program, including the λmax setpoint and the λmin setpoint, are normally based on the transmission speed error incurred at a particular job site. The smallest transmission speed error selected for a given site (λmax setpoint) may also depend on the programmed values of λmax and λmin. Similarly, the largest transmission speed error selected for a given site (λmin setpoint)is dependent on the values given λmax and λmin. These parameters also affect the sensitivity of the function λ. The function λ may become too sensitive to changes in transmission speed error when transitioning between λmax λmin over a short interval. In these cases, power may be distributed erratically due to fluctuations in transmission speed error. For this reason λmax setpoint and λmin setpoint must be chosen such that λ is not significantly affected by normal fluctuations or transmission speed error.
FIG. 8 shows the values of λ with reduced λmax setpoint and λmin setpoint values. The power management controller 36 delivers the programmed maximum fraction (λmax) of available power to the implement subsystem 29 until the absolute value of the difference between the requested (desired) and actual power train speed rises to a predetermined RPM (λmax setpoint) The power management controller 36 delivers a predetermined minimum fraction (λmin) of the available power to the implement subsystem 29 upon the absolute value of the difference between the requested speed and the delivered speed exceeding a predetermined RPM.
FIG. 7 shows the same λmax and λmin setpoints as used in FIG. 5; however, the λmax and λmin values have been increased and thus the portion or fraction of available power allocated to the implement subsystem 29 has been increased, and, consequently, less power is available for the power train subsystem 19 than was available when the power management controller 36 controlled power allocation according to the curve of FIG. 5 .
FIG. 6 shows the λmax and λmin values adjusted up and down, respectively. As compared to FIG. 5, more implement subsystem 29 power (and less power to the power train subsystem 19 ) is allocated in the first section of the allocation curve and less implement subsystem power 29 is allocated than in FIG. 5 in the third section of the allocation curve.
FIG. 9 shows the operating curve of power allocation to the implement subsystem 29 with the λmax and λmin settings the same as in FIG. 5 but with changes in the λmax setpoint and the λmin setpoint. The allocation of power (λ) to the implement subsystem 29 begins to be reduced at a rather low λmax setpoint and reduction continues to a rather high λmin setpoint.
FIG. 10 is a block diagram of the power management system of this invention in an engine powered vehicle having power consuming steering, implement and power train subsystems.
INDUSTRIAL APPLICABILITY
The power management controller herein described is programmed to allocate quantities of power to the implement power subsystem 29 between maximum and minimum fractions (λ) of the available power dependent on the transmission speed error. Transmission speed error is the absolute value of the difference between the desired speed and the actual transmission speed. The chosen maximum and minimum allocations (λmax, λmin) of available power to the implement subsystem 29 are input into the computer of the power management controller together with λmax setpoint and λmin setpoint values. These parameters are selected and input into the computer to provide efficient machine operation for a particular work function and/or particular work site. In wheel loader applications, such as loading rock in the illustrated rock crusher hopper 12 , maintaining a reasonable travel speed while raising the bucket in preparation for the dumping of the raw material into the hopper, is necessary to achieve good loader productivity. When operating a construction machine with the power management system of this invention, more power is given to the power train subsystem when there are large differences between actual and desired vehicle speeds. Conversely, more power is given to the implement subsystem when there are small differences between the actual and desired vehicle speeds. By integrating the power consuming subsystems of the construction machine through actively distributing power as directed by the power management controller 36 , the actual power limitation of the machine are not readily perceived by the operator.
Each of the four parameters (λmax, λmin,λmax setpoint, λmin set point) of the λ scheduling function may be chosen and entered into the computer in response to operator preferences or feedback. These parameters allow for a customized power distribution in the construction machine for any operator and/or for any particular work site. For example, one operator may perceive excessively slow travel speed while lifting a full bucket as a power limitation. Another operator may perceive power limitation from observing slow implement responses. In either case, the parameters of the λ scheduling function may be set independently for each operator such that the power limitations of the wheel loader are not readily perceivable. Furthermore, the parameters that define the function of λ have physical meaning. This allows for easier tuning in the field.
This invention provides flexibility in the distribution of power in construction machinery based on the perception of power limited modes by any operator. When this power management controller is applied to wheel loaders there is an important additional benefit of reducing the cycle time required for loading and dumping operations, such as loading rock crusher hoppers.
Other aspects, objects and advantages of this invention can be obtained from a stud of the drawings, the disclosure and the appended claims. | A power management controller for a machine which may be subjected to work assignments taxing the available power of the machine which automatically allocates power to the machine subsystems to ensure continued acceptable machine performance as power demands change. | 4 |
FIELD OF THE INVENTION
The invention relates to a process for the production of microspheres from acrolein type compounds and to the thus prepared products. The microspheres may be fluorescent, magnetic and there can be prepared hybrido-microspheres. The microspheres are useful for various purposes such as cell labelling, cell separation, receptor separation, affinity chromatography, diagnostic purposes, enzyme immobilization, drug delivery and the like. The microspheres can be bound to various compounds having amino groups, such as drugs, enzymes, antibodies and antigens which retain their activity. The novel acrolein-type compound microspheres can be prepared by a variety of processes which are adjusted according to the desired product as regards diameter and other properties.
BACKGROUND OF THE INVENTION
There exists a great interest in the scientific community in developing a reliable technique for the isolation of cell surface receptors and for separating cells of various types. Labelling of specific receptors on cell surfaces has a great importance for understanding of various biological phenomena, such as cell-cell recognition in development, cell communication and differences between normal and tumor cell surfaces. Mapping of antigens and carbohydrate residues on the surface of cells has been studied intensively by various techniques, for example, using fluorescent (or radioactive) antibodies or lectins, or by binding biological macromolecules such as ferritin, hemocyanin, viruses and peroxidase to antibodies or lectins. The biological macromolecules were used as markers for transmission electron microscopy or for scanning electron microscopy (SEM). Polymeric microspheres were used also as markers for cell labelling. Polystyrene latex particles have been utilized as immunological markers for use in the SEM techniques. Such particles, because of their hydrophobic character, stick non-specifically to many surfaces and molecules and therefore limit their broad application. Many other types of polymeric microspheres which were hydrophilic were synthesized and were used for labelling cell surface receptors (Table 1).
TABLE 1 Classes of Hydrophilic Crosslinked Microspheres
1. Em class: methylmethacrylate (MMA) 2-hydroxyethylmethacrylate (HEMA), methacrylic acid (MA), and ethylene glycol dimethacrylate (EGDMA). a
2. L class: HEMA,MA,and bisacrylamide (BAM). b
3. BAH class: HEMA, acrylamide (AA),MA,and BAM. b
4. DMA class: HEMA, 2-dimethylaminoethylmethacrylate (DMA),and BAM. b
5. PVP class: 4-vinyl pyridine alone or with HEMA and/or AA. b
The labelling procedure was carried out by using either the direct or the indirect methods (FIG. 1).
In both methods the first step requires the covalent binding of a purified antibody to a microsphere through the functional groups on its surface. In the direct method the immunomicrospheres (microspheres to which specific antibody is covalently bound) seek out the cell antigens and bind to it, and in the indirect method an intermediate antibody is employed.
The microspheres, depending on the initial monomer composition, had either carboxyl, hydroxyl, amide and/or pyridine groups on their surface. The functional groups were used to covalently bind antibodies and other proteins to the microspheres by using either the cyanogen bromide, carbodiimide, or glutaraldehyde methods (FIGS. 2 and 3).
The last step of the microspheres derivatization technique, prior to protein binding, consisted of a reaction with glutaraldehyde, designed to introduce reactive aldehyde groups on the surface of the beads.
Recently, a patent application was filed by A. Rembaum and S. Margel describing a method for preparation of polyglutaraldehyde microspheres U.S. Ser. No. 21,988, filed Mar. 19, 1979, and now U.S. Pat. No. 4,267,235. These polyaldehyde microspheres were used for binding in a single step appropriate proteins at physiological pH.
SUMMARY OF THE INVENTION
The present invention relates to a novel synthesis of polyacrolein microspheres, homo and hydrido microspheres and to their biological potential uses.
Polyacrolein Microspheres
Polyacrolein microspheres were prepared in two ways:
(a) polymerization of acrolein under basic conditions in the presence of appropriate surfactants-anionic microspheres; and
(b) radical polymerization of acrolein in the presence of appropriate surfactants, without or in presence of other acrylic monomers, radicalic microspheres.
(a) Basic Conditions
Polymerization of acrolein, in aqueous media under basic conditions, results in the formation of the water insoluble polyacrolein polymer. The polymerization is first order related to acrolein concentration and the rate is dependent on the pH of the polymerization (FIG. 4)--the higher the pH, the faster the polymerization. Analysis by IR spectroscopy confirms the presence of aldehyde groups as well as hydroxyl groups, carboxyl groups, ether groups and double bonds. At very high pH (higher than 13.5), due to Cannizzaro reaction, (two aldeyde groups react to give one hydroxyl group and one carboxyl group) a water soluble polyacrolein is obtained.
Anionic Polyacrolein Microspheres
Polymerization of acrolein, in aqueous media under basic conditions and in the presence of appropriate surfactants (ionic, i.e. anionic and cationic), results in the formation of polyacrolein microspheres (FIG. 5). The size of the microspheres can be controlled by changing either the acrolein concentration (FIG. 6), surfactant concentration (FIG. 7) or pH of the polymerization (FIG. 8). Addition of dimethylformamide to the aqueous medium (or other correlated solvents e.g. dimethyl-sulfoxide) increases the solubility of acrolein and results in the formation of uniform large polyacrolein beads.
Fluorescent or magnetic microspheres were obtained by carrying out the acrolein polymerization in the presence of appropriate fluorochromic (e.g. fluorescein isothiocyanate, aminofluorescein, tetramethyl rhodamine isothiocyanate, etc) or ferrofluidic compounds, respectively.
(b) Radical Polymerization of Acrolein
Polymerization of acrolein in aqueous media was carried out by using redox initiators, such as ammonium persulfate-silver nitrate, or cobalt radiation (Coy). The structure of the polyacrolein obtained in a simplified form is ##STR1## where n is an integer of 100 to 10,000, and it is different from that obtained by the basic polymerization. The hydrophilicity (and therefore the specificity towards cells) of the polyacrolein, obtained by the radical polymerization, can be increased by either stirring the polymer at a high pH (approximately pH 12) of an aqueous solution (due to Cannizzaro reaction) or by copolymerizing acrolein with hydrophilic monomers (such as hydroxy methyl-methacrylate).
Radical Polyacrolein Microspheres
Radical polymerization of acrolein, in the presence of appropriate surfactants, results in the formation of the radical microspheres (which have a different structure than that obtained by the basic polymerization.) Increasing the pH (of the suspension solution) to a value between 11.5 to 13 will increase the hydrophilicity of these microspheres. Copolymerization of acrolein with hydrophilic monomers, in the presence of appropriate surfactants, also produces more hydrophylic microspheres.
HYBRIDO MICROSPHERES
The anionic polyacrolein microspheres have been coated with the radicalic microspheres (FIG. 9). The relatively large anionic microspheres are completely covered with the smaller radical beads, e.g. 2.0μ anionic beads are covered with 0.1μ radical beads. However, increasing the size of the radical microspheres to 0.5μ will cause the radical beads to detach from the surface of the anionic microspheres. The coating procedure is based on the radical polymerization of acrolein in the presence of the anionic microspheres. The mechanism of the coating involves the grafting of the radical microspheres onto the surface of the anionic beads through their double bonds.
Based on this grafting technique the anionic polyacrolein microspheres had been coated with may other types of polymeric microspheres, e.g. polyvinylpyridine microspheres (0.2μ diameter) were grafted on the surface of the anionic polyacrolein beads (2μ diameter) by carrying out the radical polymerization of 4-vinylpyridine in the presence of the anionic polyacrolein beads.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The invention is illustrated with reference to the enclosed Figures in which:
FIG. 1 is a schematic representation of direct (a) and indirect (b) labelling of living cells by means of immunomicrospheres;
FIG. 2 is a reaction scheme for the cyanogen bromide and the carbodiimide procedures;
FIG. 3 is a reaction scheme for the glutaraldehyde procedure;
FIG. 4 illustrates first-order rate plates, at various pH's for acrolein polymerization in aqueous media (temp. 23° C., acrolein concentration 2%);
FIG. 5 illustrates scanning electron microscopy photomicrographs of polyacrolein microspheres of various sizes;
FIG. 6 illustrates size of polyacrolein microspheres as a function of acrolein concentration (temp. 23° C., pH 10, surfactant (PGL-NaHSO 3 ) 0.5% w/v);
FIG. 7 illustrates size of polyacrolein microspheres as a function of surfactant (PGL-NaHSO 3 ) concentration (temp. 23° C. pH 10, acrolein 15% w/v);
FIG. 8 illustrates size of polyacrolein microspheres as a function of pH polymerization (temp. 23° C., acrolein 15% w/v, surfactant (PGL-NaHSO 3 ) 0.5% w/v).
FIG. 9 illustrates scanning electron microscopy photomicrographs of hybrido polyacrolein microspheres.
FIG. 9A illustrates 2.0μ average anionic polyacrolein microspheres coated with 0.1μ radicalic polyacrolein microspheres (×4600).
FIG. 9B illustrates 2.0μ anionic polyacrolein microspheres coated with 0.1 radicalic polyacrolein microspheres (×12000).
EXAMPLE 1
Synthesis of the surfactant -PGL-NaHSO 3
This surfactant was prepared by the reaction of polyglutaraldehyde (PGL) and sodium hydrogen sulfite (NaHSO 3 ), as follows: 12.5 g NaHSO 3 were dissolved in 30 ml H 2 O. 5 g of PGL was then added and the solution was stirred until all the PGL was dissolved. The solution was dialysed extensively against H 2 O (molecular weight cutoff of the dialysing bag was 3,500), and then lyophilized.
EXAMPLE 2
Formation of Polyacrolein Microspheres under Basic Conditions
0.2 N aqueous NaOH solution was added dropwise to a solution containing 8% w/v acrolein and 0.5% of the surfactant PGL-NaHSO 3 until pH 10.5 was reached. The reaction was continued for 2 hours, and the produced microspheres (diameter 0.1μ) were then washed four times by centrifugation at 2000×g for 20 minutes. By varying the surfactant and/or the acrolein concentration, the pH of polymerization or the solvent, the size of the microspheres can be changed in a predictable way.
EXAMPLE 3
Magnetic Microspheres
Example 2 was repeated in the presence of 5% (v/v) of a ferrofluidic solution (aqueous dispersion of Fe 3 O 4 , sold by Ferrofluidics, Burlington, Mass., No. A01 5% w/v) and resulted in the formation of magnetic polyacrolein microspheres of average size of 0.04μ. The magnetic microspheres were washed by dialysis and then separated from diamagnetic impurities by means of a permanent magnet.
EXAMPLE 4
Fluorescent Microspheres
Example 2 was repeated in the presence of 0.008% tetramethyl rhodamine isothiocyanate and resulted in the formation of 0.1μ diameter fluorescent polyacrolein microspheres.
EXAMPLE 5
Example 2 was repeated in the presence of methacrolein (instead of acrolein). Microspheres in average size of 0.1μ were produced.
EXAMPLE 6
Example 2 was repeated in the presence of crotonaldehyde (instead of acrolein). Microspheres in average size of 0.2μ were obtained.
EXAMPLE 7
The procedure of Example 2 was repeated substituting the surfactant PGL-NaHSO 3 by the anionic surfactants Dowfax 2A1 (or Dowfax 3B2). There were obtained polyacrolein microspheres in average size of 0.1μ.
EXAMPLE 8
The procedure of Example 2 was repeated substituting the surfactant PGl-NaHSO 3 with the non-ionic surfactant Polysurf 10-36B (based on a copolymer of acrylamide and isobutoxy acrylamide, provided by Bartig Industries, Inc., Birchwood Ave, New Canaan, Conn. 06840 U.S.A.). No polyacrolein microspheres were obtained by this process.
EXAMPLE 9
0.2 N aqueous was added dropwise to an aqueous solution containing 10% dimethyl formamide 25% (w/v) acrolein and 0.08% (w/v) of the surfactant PGL-NaHSO 3 unit pH 11.5 was reached. The reaction was continued for an hour and then the produced monodispersed microspheres 3μ diameter) were washed 4 times by spinning at 500×g for 10 minutes.
EXAMPLE 10
10 ml of an aqueous solution containing 10% (w/v) dimethyl formamide and 0.3% (w/v) of the surfactant PGL-Na-HSO 3 was brought to pH 11.2. The solution was stirred gently and 5 ml of acrolein was added. The reaction continued for 15 minutes and the produced beads (average size of 80μ) were washed several times by decantation.
EXAMPLE 11
Formation of Polyacrolein Microspheres under Radical Conditions
100 ml of an aqueous solution containing 9% (w/v) acrolein and 0.5% (w/v) polyethylene oxide (m.w. 100,000) was deaerated with argon and radiated then with cobalt source (1 Mega rad). The produced microspheres (0.15μ size) were washed by centrifugation 4 times at 2000×g for 30 minutes.
EXAMPLE 12
Example 11 was repeated in the presence of 5% (w/v) of hydroxy methyl methacrylate. Microspheres in average size of 0.2μ were obtained.
EXAMPLE 13
Example 11 was repeated in the presence of 1% (w/v) N.N'-methylene-bis-(acrylamide) as cross linker. Microspheres in average size of 0.15μ were obtained.
Example 14
Example 11 was repeated in the presence of methacrolein. Microspheres in average size of 0.2μ were obtained.
EXAMPLE 15
Example 14 was repeated in the presence of 0.008% (w/v) of fluorescein isothiocyanate and resulted in the formation of 0.2μ fluorescent polymethacrolein microspheres.
EXAMPLE 16
Example 11 was repeated in the prescence of methyl vinyl ketone. Microspheres in average size of 0.2μ were obtained.
EXAMPLE 17
The microspheres prepared as in Example 11 were treated for 12 hours in a basic aqueous solution (pH 12.0) and then washed four times by spinning at 2000×g for 30 minutes. The hydrophilic microspheres obtained had an average size of 0.15μ.
EXAMPLE 18
120 ml of an aqueous solution containing 9% (w/v) acrolein, 0.5% (w/v) polyethylene oxide (m.w. 100,000) and 1.0 mmol of ammonium persulfate was deaerated with argon. 1.0 mmol of AgNO 3 was then added to the stirred solution. The reaction continued for 12 hours and the produced beads with average size of 0.1μ were washed 4 times by spinning at 2000×g for 20 minutes.
EXAMPLE 19
Example 18 was repeated in the presence of 5% (v/v) of ferrofluid solution and resulted in the formation of magnetic polyacrolein microspheres of average size of 0.05μ. The magnetic microspheres were washed by dialysis and then separated from diamagnetic impurities by means of a permanent magnet.
EXAMPLE 20
Formation of Hybrido Microspheres
4 ml of an aqueous solution containing 9% (w/v) acrolein, 0.5% (w/v) polyethylene oxide (m.w. 100,000) and 100 mg of the anionic polyacrolein beads of 2.0μ size was deaerated with argon. The stirred solution was then radiated with cobalt source (1 mega rad). The grafted microspheres (FIG. 9) were washed from excess of 0.1μ radical microspheres by spinning four times at 500×g for 10 minutes.
EXAMPLE 21
4 ml of an aqueous solution containing 8% (w/v) acrolein, 0.5% (w/v) polyethylene oxide (m.w. 100,000), 0.06 mmol of ammonium persulfate and 100 mg of the anionic polyacrolein beads of 2.0μ size was deaerated with argon to the stirred solution 0.06 milimole of AgNO 3 was then added. The reaction continued for 12 hours and the grafted microspheres were washed by centrifugation 4 times at 500×g for 10 minutes.
EXAMPLE 22
The procedure of example 20 was repeated substituting acrolein with 1% (w/v) 4-vinyl pyridine.
EXAMPLE 23
The procedure of example 21 was repeated substituting acrolein with 1% (w/v) 4-vinyl pyridine.
EXAMPLE 24
Labelling of Red Blood Cells with Microspheres
Polyacrolein microspheres obtained by basic polymerization were shaken for 2 hours, at 4° C., with purified goat anti rabbit IgG (GxRIgG) (1 mg microspheres, 0.1 mg GxRIgG in total volume of 0.15 ml PBS). Thereafter unbound antibody was separated by passing the microsphere suspension through a Sepharose 4B column. The separation was monitored spectrophotometrically at A×280 nm. The free aldehyde groups of the conjugate microspheres antibody were quenched with 2% (w/v) bovine serum albumin solution for several hours at 4° C.
Fresh human RBC, from a normal donor, were shaken for 50 min at 4° C. with rabbit anti human RBC (Cappel Lab. Inc.) (10 6 human RBC with 0.8 μg rabbit against human RBC in 0.1 ml PBS solution). The sensitized cells were separated and washed 4 times by spinning the cells suspension in an international centrifuge at 500×g. The goat anti rabbit derivatized microspheres were then added to the sensitized human RBC and the mixture was shaken at 4° C. for 1 hour. The RBC were separated from unreacted derivatized microspheres by centrifugation 3 times at 500×g. The labelled cells were resuspended in PBS and were examined in light fluorescent microscopy and with fluorescence-activated cell sorter (FACS-11 (Becton-Dickinson - photomultiplier 600V, 2 filters - 550 nm).
EXAMPLE 25
Separation of turkey RBC from human RBC
A mixture containing 10 6 human RBC and 10 6 turkey RBC was treated with magnetic microspheres by using the former labelling procedure. Then a small magnet was fitted on the outside wall of a vial containing PBS solution of the cells mixture. After 10 minutes, cells which were not attracted to the wall were isolated. The attracted cells were resuspended with PBS and the magnetic separation was repeated twice. Examination with light microscopy showed that more than 90% of the attracted cells were human RBC.
Polyacrolein microspheres can be used for cell labelling and cell separation of other systems (e.g. labelling and separation of B and T cells) as well as for other purposes such as drug delivery, enzyme immunoassay, and enzyme mobilization. | Suspension polymerization of acrolein type compounds in the presence of appropriate surfactants results in the formation of microspheres in size ranging from 0.03μ to 80μ. Fluorescent and magnetic microspheres are obtained by carrying out the same polymerization in the presence of appropriate fluorochromic or ferrofluidic compounds, respectively. Hybrido polyacrolein microspheres are obtained by grafting one type of such microspheres on another type. Immunomicrospheres were formed by binding covalently at physiological pH appropriate proteins to the microspheres. The immunomicrospheres can be used for various biological applications, such as specific markers for labelling cell surface receptors, for cell separation, for diagnostic purposes, etc. | 0 |
TECHNICAL FIELD
[0001] This application relates to subsurface drilling, specifically, to downhole tools which include data logging functions. Embodiments are applicable to drilling wells for recovering hydrocarbons.
BACKGROUND
[0002] Recovering hydrocarbons from subterranean zones typically involves drilling wellbores.
[0003] Wellbores are made using surface-located drilling equipment which drives a drill string that eventually extends from the surface equipment to the formation or subterranean zone of interest. The drill string can extend thousands of feet or meters below the surface. The terminal end of the drill string includes a drill bit for drilling (or extending) the wellbore. Drilling fluid, usually in the form of a drilling “mud”, is typically pumped through the drill string. The drilling fluid cools and lubricates the drill bit and also carries cuttings back to the surface. Drilling fluid may also be used to help control bottom hole pressure to inhibit hydrocarbon influx from the formation into the wellbore and potential blow out at surface.
[0004] Bottom hole assembly (BHA) is the name given to the equipment at the terminal end of a drill string. In addition to a drill bit, a BHA may comprise elements such as: apparatus for steering the direction of the drilling (e.g. a steerable downhole mud motor or rotary steerable system); sensors for measuring properties of the surrounding geological formations (e.g. sensors for use in well logging); sensors for measuring downhole conditions as drilling progresses; one or more systems for telemetry of data to the surface; stabilizers; heavy weight drill collars; pulsers; and the like. The BHA is typically advanced into the wellbore by a string of metallic tubulars (drill pipe).
[0005] Modern drilling systems may include any of a wide range of mechanical/electronic systems in the BHA or at other downhole locations. Such electronics systems may be packaged as part of a downhole probe. A downhole probe may comprise any active mechanical, electronic, and/or electromechanical system that operates downhole. A probe may provide any of a wide range of functions including, without limitation: data acquisition; measuring properties of the surrounding geological formations (e.g. well logging); measuring downhole conditions as drilling progresses; controlling downhole equipment; monitoring status of downhole equipment; directional drilling applications; measuring while drilling (MWD) applications; logging while drilling (LWD) applications; measuring properties of downhole fluids; and the like. A probe may comprise one or more systems for: telemetry of data to the surface; collecting data by way of sensors (e.g. sensors for use in well logging) that may include one or more of vibration sensors, magnetometers, inclinometers, accelerometers, nuclear particle detectors, electromagnetic detectors, acoustic detectors, and others; acquiring images; measuring fluid flow; determining directions; emitting signals, particles or fields for detection by other devices; interfacing to other downhole equipment; sampling downhole fluids; etc.
[0006] Downhole conditions can be harsh. A probe may experience high temperatures; vibrations (including axial, lateral, and torsional vibrations); shocks; immersion in drilling fluids; high pressures (20,000 p.s.i. or more in some cases); turbulence and pulsations in the flow of drilling fluid past the probe; fluid initiated harmonics; and torsional acceleration events from slip which can lead to side-to-side and/or torsional movement of the probe. These conditions can shorten the lifespan of downhole probes and can increase the probability that a downhole probe will fail in use. Replacing a downhole probe that fails while drilling can involve very great expense.
[0007] There remains a need for ways to provide downhole tools that are cost-effective.
SUMMARY
[0008] The invention has a number of different aspects. These aspects include, without limitation, kits, methods, systems and apparatus for data logging. Particular kits, methods, systems and apparatus for data logging according to the invention may be applied in high temperature environments (e.g. over 100° C.) such as may be encountered in downhole drilling.
[0009] One example aspect provides a data logger comprising a first data store, a second data store and a controller connected to receive output from a temperature sensor indicating a temperature of the first data store. The controller may be configured to write data to the first data store and to switch to writing the data on the second data store if the indicated temperature of the first data store exceeds a first threshold temperature. The first and second data stores may be of different types. The second data store may have an operating temperature range that extends to temperatures above a maximum operating temperature of the first data store. The first threshold temperature may be within or at a limit of an operating temperature range for the first data store.
[0010] In some embodiments, the data logger comprises a power supply connected to supply a bias voltage to the first data store and the controller is connected to discontinue supply of the bias voltage to the first data store if the indicated temperature of the first data store exceeds a second threshold. The second threshold may be equal to or greater than the first threshold.
[0011] In some embodiments, upon the temperature of the first data store transitioning from above the first threshold to below the first threshold, the controller is configured to copy any data recorded in the second data store to the first data store.
[0012] In some embodiments, the first data store comprises a non-volatile memory. In other embodiments, the first data store comprises a flash RAM. In further embodiments, each of the first and second data stores comprises a single integrated circuit. In some embodiments, the maximum operating temperature of the first data store is 80° C. or less. In some embodiments, the capacity of the first data store is at least twice a capacity of the second data store.
[0013] In some embodiments, the data logger comprises a network interface connectable to receive data to be logged. The network interface may comprise a CANBUS interface.
[0014] Further aspects of the invention and features of example embodiments are illustrated in the accompanying drawings and/or described in the following description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] The accompanying drawings illustrate non-limiting example embodiments of the invention.
[0016] FIG. 1 is a schematic view of a drilling operation.
[0017] FIG. 2 is a block diagram showing functional components of an example downhole tool.
[0018] FIG. 3 is a block diagram showing another downhole tool according to an example embodiment.
DESCRIPTION
[0019] Throughout the following description specific details are set forth in order to provide a more thorough understanding to persons skilled in the art. However, well known elements may not have been shown or described in detail to avoid unnecessarily obscuring the disclosure. The following description of examples of the technology is not intended to be exhaustive or to limit the system to the precise forms of any example embodiment. Accordingly, the description and drawings are to be regarded in an illustrative, rather than a restrictive, sense.
[0020] FIG. 1 shows schematically an example drilling operation. A drill rig 10 drives a drill string 12 which includes sections of drill pipe that extend to a drill bit 14 . The illustrated drill rig 10 includes a derrick 10 A, a rig floor 10 B and draw works 10 C for supporting the drill string. Drill bit 14 is larger in diameter than the drill string above the drill bit. An annular region 15 surrounding the drill string is typically filled with drilling fluid. The drilling fluid is pumped through a bore in the drill string to the drill bit and returns to the surface through annular region 15 carrying cuttings from the drilling operation. As the well is drilled, a casing 16 may be made in the well bore. A blow out preventer 17 is supported at a top end of the casing. The drill rig illustrated in FIG. 1 is an example only. The methods and apparatus described herein are not specific to any particular type of drill rig.
[0021] This invention provides downhole tools which have two or more data stores having different properties. Some embodiments address the problem that electronic components, including memories that are useful for storing data, can typically only operate reliably within a given temperature range. Manufacturers of memory devices typically specify a range of acceptable operating temperatures for their memory devices. A problem with downhole applications is that temperatures are often quite high. In some cases, temperatures are well over 100° C. For example, temperatures of 150° C. are sometimes encountered in downhole environments. Such temperatures are in excess of the maximum specified operating temperatures for many memory devices. For example, many memory devices have maximum operating temperatures of 65° C.
[0022] This issue is currently addressed by using in downhole tools memory devices that have high temperature ratings. Memory devices having maximum operating temperatures of 200° C. or more are commercially available. However, such memory devices tend to be very expensive and tend to require more space than low temperature rated data storage devices. Furthermore, individual high-temperature memory devices have data storage capacities that are significantly less than are available in individual devices having lower temperature ratings.
[0023] An alternative to using high temperature rated storage devices is to use the commonly available and relatively inexpensive storage devices designed for operation at low temperatures and to use these storage devices notwithstanding the fact that the downhole temperatures may exceed the maximum operating temperature ratings of the low temperature devices. This, however, results in a severely reduced lifetime for these devices. If a memory device fails while the downhole tool is in use then it may become necessary to trip the downhole tool out of the well bore in order to replace the failed memory device. This can be very expensive.
[0024] This invention takes advantage of the fact that commonly available low temperature rated data storage devices such as flash integrated circuits are typically rated to survive at the temperatures commonly experienced downhole as long as they are not powered, operated (e.g. read/write) above their maximum operating temperatures. For example, the Spansion™ NAND flash memory chip is available in 1 Gb, 2 Gb, 4 Gb densities and has an operating temperature range of −40° C. to 85° C., a temperature range under bias of −50° C. to 125° C., and a storage temperature range of −65° C. to 150° C.
[0025] FIG. 2 is a block diagram showing relevant parts of a downhole tool according to an example embodiment of the invention. Downhole tool 20 comprises data generating components 22 . Data generating components 22 may, for example, comprise any number of sensors such as gamma sensors, magnetic field sensors, resistivity sensors, optical sensors, and the like. Data generating components 22 are connected to a memory system 24 by one or more data buses 25 .
[0026] Memory system 24 includes two data storage devices that differ from one another in their operating temperature ranges. Device 24 A may be a standard data storage device, such as a flash IC which has an operating temperature range, for example, having a maximum operating temperature of 85° C. or 125° C. or less. In some embodiments, data storage device 24 A has a maximum operating temperature of 65° C. or 75° C., for example.
[0027] A second data storage device 24 B has a higher operating temperature range. For example, the operating temperature range of data storage device 24 B may be up to 175° C. or 200° C. As a consequence, data storage device 24 A may be significantly less expensive than data storage device 24 B. In some embodiments, data storage device 24 A has a significantly larger capacity for data than data storage device 24 B. For example, data storage device 24 A may comprise a flash storage drive having a capacity between 64 megabits and 1 gigabit while data storage device 24 B may comprise a flash storage drive having a capacity between 8 megabits and 64 megabits.
[0028] To improve performance, storage devices 24 A, 24 B may have read/write speeds that are approximately the same. In other embodiments, the writing speed is slower than the reading speed.
[0029] Memory system 24 includes a temperature sensor 24 C and a controller 24 D which receives an input from the temperature sensor 24 C. Controller 24 D controls whether data received by way of data buses 25 is written to data storage device 24 A or data storage device 24 B. If the temperature detected by sensor 24 C is greater than a threshold temperature (indicating that the maximum operating temperature of data storage device 24 A has been reached or has nearly been reached) then data storage controller 24 D directs data received on bus or busses 25 to high temperature data store 24 B. On the other hand, if temperature sensor 24 D detects a temperature lower than the threshold, then received data is stored on low-temperature device 24 B.
[0030] In some embodiments, if the ambient temperature is above the threshold temperature for a period of time, and data has been buffered into higher temperature data store 24 B, and the temperature then falls to below the threshold temperature, upon the temperature falling to below the threshold temperature (and perhaps remaining below the threshold temperature for a period of time), any data that has been recorded to high temperature data store 24 B may be transferred on to low temperature data store 24 B. By doing so, capacity of the high-temperature data store 24 B may be freed in case the temperature again rises to a temperature above the threshold temperature.
[0031] In some embodiments, data is stored in data store 24 A using a table. The table may organize data entries into sectors. As data is entered in data store 24 A, either from data store 24 B or from elsewhere, it would increase the sector number counter and save the new data accordingly. In other embodiments, a pointer is included with data entries to indicate where the data is written or should be written.
[0032] In some embodiments, controller 24 D controls a power supply 24 E that supplies bias voltage to low-temperature data store 24 A. In such embodiments, where the temperature detected by temperature sensor 24 C exceeds a threshold (that can be the same or higher than the first threshold mentioned above), then controller 24 D may control supply 24 E to discontinue supplying bias power to data storage device 24 A. This may extend the temperature range to which data storage device 24 A may be exposed without damage.
[0033] In an example embodiment, a controller 24 D discontinues writing to low temperature memory 24 A and writes instead to a higher temperature memory 24 B when a temperature as sensed by sensor 24 C exceeds approximately 65° C. If the temperature rises to a temperature of, for example, above 80° C., bias voltage to low temperature data store 24 A is shut off. If the temperature falls again to a temperature within the operating range of low temperature data store 24 A, then controller 24 D once again applies bias voltage to data storage device 24 A and transfers in to data storage device 24 A any data that has accumulated in high temperature data storage device 24 B. Controller 24 D then directs any further data received to low-temperature data storage device 24 A until such time as the temperature once again rises to above the first threshold. In some embodiments, data storage device 24 A comprises one or more flash RAM devices. Data storage device 24 B may also comprise one or more flash RAM devices.
[0034] Temperature sensor 24 C is not necessarily dedicated to memory system 24 . For example, temperature sensor 24 C may be a temperature sensor that senses a temperature of downhole tool 20 generally.
[0035] FIG. 3 shows an example downhole tool 30 according to one embodiment. Downhole tool 30 comprises one or more sensor modules 32 , one or more data telemetry modules 34 , and a data storage module 35 all interconnected by a bus 37 . Bus 37 may, for example, comprise a CANBUS, an RS-422, an RS-485 or a K-Line. Data storage module 35 may have a construction as shown for data store 24 of FIG. 2 , for example.
[0036] While a number of exemplary aspects and embodiments have been discussed above, those of skill in the art will recognize certain modifications, permutations, additions and sub-combinations thereof. It is therefore intended that the following appended claims and claims hereafter introduced are interpreted to include all such modifications, permutations, additions and sub-combinations as are within their true spirit and scope.
Interpretation of Terms
[0037] Unless the context clearly requires otherwise, throughout the description and the claims:
“comprise,” “comprising,” and the like are to be construed in an inclusive sense, as opposed to an exclusive or exhaustive sense; that is to say, in the sense of “including, but not limited to”. “connected,” “coupled,” or any variant thereof, means any connection or coupling, either direct or indirect, between two or more elements; the coupling or connection between the elements can be physical, logical, or a combination thereof. “herein,” “above,” “below,” and words of similar import, when used to describe this specification shall refer to this specification as a whole and not to any particular portions of this specification. “or,” in reference to a list of two or more items, covers all of the following interpretations of the word: any of the items in the list, all of the items in the list, and any combination of the items in the list. the singular forms “a,” “an,” and “the” also include the meaning of any appropriate plural forms.
[0043] Words that indicate directions such as “vertical,” “transverse,” “horizontal,” “upward,” “downward,” “forward,” “backward,” “inward,” “outward,” “vertical,” “transverse,” “left,” “right,” “front,” “back,” “top,” “bottom,” “below,” “above,” “under,” and the like, used in this description and any accompanying claims (where present) depend on the specific orientation of the apparatus described and illustrated. The subject matter described herein may assume various alternative orientations. Accordingly, these directional terms are not strictly defined and should not be interpreted narrowly.
[0044] Where a component (e.g. a circuit, module, assembly, device, drill string component, drill rig system, etc.) is referred to above, unless otherwise indicated, reference to that component (including a reference to a “means”) should be interpreted as including as equivalents of that component any component which performs the function of the described component (i.e., that is functionally equivalent), including components which are not structurally equivalent to the disclosed structure which performs the function in the illustrated exemplary embodiments of the invention.
[0045] Specific examples of systems, methods and apparatus have been described herein for purposes of illustration. These are only examples. The technology provided herein can be applied to systems other than the example systems described above. Many alterations, modifications, additions, omissions and permutations are possible within the practice of this invention. This invention includes variations on described embodiments that would be apparent to the skilled addressee, including variations obtained by: replacing features, elements and/or acts with equivalent features, elements and/or acts; mixing and matching of features, elements and/or acts from different embodiments; combining features, elements and/or acts from embodiments as described herein with features, elements and/or acts of other technology; and/or omitting combining features, elements and/or acts from described embodiments.
[0046] It is therefore intended that the following appended claims and claims hereafter introduced are interpreted to include all such modifications, permutations, additions, omissions and sub-combinations as may reasonably be inferred. The scope of the claims should not be limited by the preferred embodiments set forth in the examples, but should be given the broadest interpretation consistent with the description as a whole. | A data logger comprising a first data store, a second data store and a controller connected to receive output from a temperature sensor indicating a temperature of the first data store. The controller may be configured to write data to the first data store and to switch to writing the data on the second data store if the indicated temperature of the first data store exceeds a first threshold temperature. The first and second data stores may be of different types. Upon the temperature of the first data store transitioning from above the first threshold to below the first threshold, the controller may be configured to copy any data recorded in the second data store to the first data store. | 4 |
CROSS-REFERENCE TO A RELATED APPLICATION
This application is a National Phase patent application of International Patent Application Number PCT/EP2009/061701, filed on Sep. 9, 2009, which claims priority of German Patent Application Number 10 2008 046 639.5, filed on Sep. 9, 2008.
BACKGROUND
The invention relates to a server system for providing at least one service, a method for providing a service via a server system and a method for executing an application program on a user's computer.
Such a server system for providing at least one service has an interface for connecting a server to a user's computer and an authentication means that is designed and provided to request personal identification data of a user who logs onto the server via the user's computer and permits the user's computer access if authentication is successful.
In the present case a server is to be understood as a computer or computer system which offers services in form of services or data and which can be accessed by different user's computers, the so-called clients. Hereby, the server is set up at a central location in a communication network, for instance the internet, via which a multitude of computers and computer systems are connected with each other for exchanging data. A user can connect to the server via a user's computer and thus can access the server.
In order to avoid that non-authorized users access a server, conventional servers use an authentication, which asks for personal identification data of a user, for instance a user name and a password determined in advance. The server requests thereby the user to enter its user's name and password and permits the user only access to the services of the server if user name and password have been verified. This authentication is also called a weak authentication.
SUMMARY
The object of the present invention is to provide a server system and a method for providing a service and a method for executing an application program, with which an increased protection, when operating the server system, is achieved and an access to services by a non-authorized user can be avoided with increased reliability.
This object is being solved by a server system according to an exemplary embodiment of the invention.
In case of a server system of the previously mentioned kind a server protection system is provided that is designed and provided to compare after successful authentication by the authentication means additional user's computer specific identification data with identification data stored in advance on the server and to grant authorization to the user's computer to have at least one service depending on the comparison of the user's computer specific identification data.
The object is also being solved by a method for providing a service via a server system, wherein a user connects to a server via a user's computer for obtaining access to a service offered by the server, the server requests personal identification data of the user for authentication and the server permits access for the user's computer in case of successful authentication. Hereby, it is provided that after successful authentication additional user's computer specific identification data are compared with identification data stored on the server in advance and the user's computer is granted authorization for having the at least one service depending on the comparison of the user's computer specific identification data.
The present invention is based on the principle idea that besides the certification of personal identification data for authentication of the user additional user's computer specific identification data are requested and to grant the access to a service of the server in dependency on the certification of the additional user's computer specific identification data. The personal identification data of the user can be thereby the user's name and a password, while the additional user's computer specific identification data can be for instance further personal data of the user, a network address of the user's computer, an identification of a pre-determined application program of the user's computer and/or a pre-determined time window. The personal identification data of the user come thereby from the user itself, while the additional user's computer specific identification data come either from the user itself or directly from the user's computer.
If the user's computer specific identification data are additional personal information of the user, the server protection system requires the user to enter the additional personal information—for instance the birthday of the user, the address of the user or the like—and the user transfers the user's computer specific identification data to the server via the user's computer.
If the additional user's computer specific identification data is on the other side the network address of the user's computer, then the server obtains these data in form of the so-called Mac- or IP-address directly from the user's computer in an automatic manner when providing the connection to the server (from the so-called “handshake” of the connection protocol).
If the additional user's computer specific identification data is the identification of an application program, this identification is directly transferred by the application program to the server for instance in form of the name of the application program or a name and password of the application program.
If the additional user's computer specific identification data is a pre-described compliance with a pre-determined time window, then the user can have access only within a pre-determined time window, wherein the server monitors the compliance of the time window by the means of an internal time.
The additional user's computer specific identification data can be arranged also individually to a user or a user group.
The access to a service by a user is therefore only granted, if after an authentication by the means of personal identification data of the user further additional user's computer specific identification data are certified in a further step. The process until the permission for access to the service is provided is therefore divided in two steps. In a first step a so-called weak authentication occurs, wherein only personal identification data, for instance, a user name and a password of a user are requested. If this first authentication is successful, then in a second step additional user's computer specific identification data are certified. For instance, it is certified if the network address (Mac-address or IP-address) of the users computer via which the user tries to access the server match the network address stored in advance on the server. If this is the case, the permission for accessing the desired service is granted to the user. In other words, in this case the user is granted only access to the server from a pre-determined user's computer with a specific network address. In analogue manner, further personal information of the user, an identification of the user application program or a time window can be requested as additional user's computer specific identification data, in order to grant the user access for instance only via a specific application program or only within a specific time window.
The permission for having the at least one service is granted to the user depending on the certification of the user's computer specific identification data. In dependency on the result of that certification different measures can thereby be taken.
It is for instance conceivable, that only in case of a successful certification; this means by the matching of the additional user's computer specific identification data with the identification data stored in advance on the server, access to the service is granted to the user.
Alternatively, it is conceivable that an access is granted, however the user is provided with another (false) service. This is also called “honey pot”.
In a third variant it is conceivable that despite of a failed monitoring of the additional user's computer specific identification data to grant an access and to provide the correct service, however, the user is put under specific observation.
In a fourth variant it is conceivable that the access in case of a failed authentication is not yet granted, but instead further user's computer specific identification data are requested for an additional authentication. Only if this additional authentication step fails also, the access is finally refused.
In addition to the mentioned measures, the server can also apply further measures, for instance to inform a system administrator or other pre-determined locations that a non-correct authenticated user tries to access the server.
The server can be for instance designed as a database server, which provides pre-determined data. Basically, the server protection system described here can be used in all server systems, which offer services and which can be accessed via a data network by user's computers (clients).
In a preferred embodiment the permission for having the at least one service is deleted after interrupting the connection of the server to the user's computer. The idea hereby is that a provided connection is completely removed after ending the connection, so that in case of a new connection again a complete authentication with requesting the personal identification data of the user in a first step and requesting or certifying the additional user's computer specific identification data occurs in a second step,
The server recognizes advantageously in a detection phase the user's computer specific identification data and stores them in a registry. After the initialization of the server protection system on the server at first a detection phase is conducted, in which the user's computer specific identification data from the user, for instance the network address of the user's computer, via which a user logs onto the server, are determined and stored. The detection phase of the server protection system can thereby occur besides the actual operation of the server in the background, wherein for instance user's computer specific identification data can also be read out from data recorded in advance.
In the detection phase it can furthermore be determined by configuring the adjustments, how it should respond to deviations of the user's computer specific identification data from identification data stored in the registry.
After finishing the detection phase the normal operating phase is then conducted as previously described, wherein for providing an access for having a desired service the additional user's computer specific identification data stored in the detection phase are certified and the access is granted in dependency on the result of this certification.
In a preferred embodiment it can be provided that the server can be exclusively accessed via a specific application program on the user's computer, wherein the connection to the server has to be provided via the application program of the user's computer. For further increasing the protection it is then possible to stipulate that the application program of the user's computer has to be conducted via an application protection system installed on the user's computer, wherein the protection system comprises an administration module and a time running monitor for starting and monitoring the application program.
Since the server can only be accessed via a specific application program and the application program can only be conducted by the means of an application protection system present on the user's computer it is guaranteed that non-authorized users cannot access the server. This application protection system of the user's computer is thereby provided to prevent a manipulation and a non-authorized execution of the application program, so that already on the part of the user's computer it is guaranteed that an access to the server by non-authorized users is not possible.
The application protection system with its administration module and its time running monitor can be designed such that in an initialization phase all system files of the user's computer are detected by the administration module, are provided with an identification and are stored in a first registry of the user's computer. In the initialization phase the application program installed on the user's computer is being told to the administration module in advance. The administration module then certifies which system files and modules are used by the application program, provides these with an additional identification and stores them in form of a reference list in a second registry of the user's computer.
When operating it can be provided and be determined by an adjustment, that the application program can be exclusively started via the administration module.
The conduction of the application program is monitored by the running time monitor. The running time monitor creates hereby at first an identification of the application program and certifies if this identification matches the identification of the application program sent to the administration module in advance. If this identification does not match, then pre-determined measures are introduced, for instance the program start is interrupted. If the identification matches, then the application program is carried out, wherein the running time monitors the access of the application program to the system files.
The running time monitor generates furthermore a protection object, in which the application program is conducted and which isolates the application program from other programs and processes. The protection object prevents that the application program can be accessed from other programs and processes and uses for instance an exclusive set of operating means, for instance a specific keyboard or a specific monitor. Then the application program cannot be accessed via other operating means, for instance by another keyboard. Any contact from the outside to the application program is prevented in this manner by the application protection system.
After ending the program the running time monitor removes completely its protection object.
The application program is therefore conducted in a safe environment. Simultaneously the access of the application program to the system files and modules is monitored, wherein the system files and modules have to match the system files and modules detected in advance by the administration module. If an identification of a system file, to which the application program tries to have access, matches an identification of the system file stored in advance, then the access to the system file by the application program is allowed and the system file is loaded. Hereby, it is certified if the identification of the system file in the first registry—corresponding to all system files of the user's computer—or in the second registry—corresponding to system files which were associated in advance with the application program—is present. If the system file is found and matches, then the system file is cleared. If the system file is on the other hand not found in one or in both registries, then the conduction of the application program is interrupted.
Advantageously, the application protection system of the user's computer and the server communicate with each other for mutual authentication. The authentication can hereby occur according to the ISO/IEC 9798-3 standard, wherein the application protection system and the server authenticate mutually and a connection of the user's computer to the server is only permitted, if the mutual authentication of the application protection system and the server is successful.
The object is also being solved by a method for conducting an application program on a users computer, wherein the application program of the users computer is conducted via an application protection installed on the user's computer, wherein the protection system comprises an administration module and a time running monitor for starting and monitoring the application program. The application program is thereby started via the administration module and the time running monitor monitors the access of the application program to the system files when the application program is conducted.
The administration module can detect system files in an initialization phase, provide them with identification and stores them in a first registry of the user's computer. In the initialization phase it is further certified, which system files are used by the application program, and these system files are provided with an additional identification and are stored in a second registry of the user's computer.
Furthermore, the application protection system can provide a protection object, in which the application program is conducted and which isolates the application program from other programs and processes. The method for conducting an application program on a user's computer by using an application protection system, a protection of selected application programs from outside attacks is provided, in particular from a manipulation by harmful software. A second possible application opportunity lies in a version and licensing control, in the frame of which for instance a license number is requested and a conducting of the application program is only possible by matching of the license number.
The method is based on two basic principles. According to the first basic principle it is being recognized via the application protection system, if a program with correct or modified system files, modules or data works data functions. This is being realized by the running time monitor. According to a second basic principle the application program is conducted within a protection object, which isolates the application program from other programs and processes and makes an access from the outside onto the application program impossible. The protection object can for instance allow the access to the application program only via an exclusive set of operating means, for instance a pre-determined keyboard and a pre-determined monitor, while an access with other means from the outside is impossible.
The cooperation of the application protection system of the user's computer with the server protection system of the server for a mutual authentication is in particular of an advantage, wherein the application protection system assures protection to the server that the application program is not manipulated and runs in a particular safe environment, while the server system for the user's computer guarantees that the user's computer communicates with the correct server.
BRIEF DESCRIPTION OF THE DRAWINGS
The idea of the present invention shall be explained in the following by the means of the examples illustrated in the Figures.
FIG. 1A-1C show schematic views for obtaining a connection of a user's computer to a server by conducting a weak authentication.
FIG. 2A-2D shows schematic views for obtaining a connection of a user's computer to a server by conducting a weak and a subsequent strong authentication.
FIG. 3 shows a schematic view of conducting an application program on a user's computer by using an application protection system.
DETAILED DESCRIPTION
The schematic views according to FIGS. 1A to 1C show the course when obtaining a connection between a user's computer 2 to a server 1 by using a conventional, weak authentication. The server 1 is thereby designed as a database server with different databases 10 , 11 .
The server 1 offers services in form of data 103 , 113 to which a user can have access via a user's computer 2 (client) and an interface 13 of the server 1 . A login account 12 of the server 1 is thereby designated to each user, via which a user can connect to the server 1 and log onto the server 1 . The login account 12 is again connected to a user account 101 , 111 of one or multiple of the databases 10 , 11 . Each user account 101 , 111 is again connected to one or multiple of so-called scrollings 102 , 112 via which access can be obtained to a certain data amount of data 103 , 113 and in which the data 103 , 113 are organized so that the user can access the data 103 , 113 and can work with the data 103 , 113 .
The access to the data 103 , 113 is therefore granted to a user via a user's computer 2 , the interface 13 , the login account 12 designated to the user, one or multiple user accounts 101 , 111 connected to the login account 12 and the scrollings 102 , 112 . FIG. 1A shows the status before obtaining the connection. In this status the connections between the login account 12 of a user, the user accounts 101 , 111 and the scrollings 102 , 112 are already obtained. Therefore, it is defined by these connections to which the databases 10 , 11 with which scrollings 101 , 112 and data 13 , 113 a user can have access.
In case of the example shown in FIG. 1A the login account 12 A is connected to the user account 101 a and via the user account 101 a to the scrollings 102 a . A user corresponding to the login account 12 a can therefore access via the login account 12 a the scrolling 102 a of the database 10 with the associated data 103 . The login account 12 b on the other side is connected to the user account 101 b of the database 10 and the user account 111 a of the database 11 , wherein the user account 101 b of the database 10 is connected to the scrollings 102 a , 102 b and the user account 111 a of the database 11 is connected to the scrollings 112 a , 112 b . The user assigned to the login account 12 b can therefore have access to the data 103 , 113 associated with the scrollings 102 a , 102 b of the database 10 and the scrollings 112 a , 112 b of the database 11 .
For obtaining the connection a user accesses the login account 12 designated to the user via a user's computer 2 and the interface 13 . This is schematically illustrated in FIG. 1B , wherein for instance a user accesses the login account 12 A via the user's computer 2 a and the interface 13 . The server 1 carries out hereby a so-called weak authentication within which the user name and the password of the users are requested. If the user name and the password match the user name and password of the login account 12 determined in advance then the authentication is successful and the user is granted the permission for accessing the databases 10 , 11 according to the interconnections defined in advance.
After closing the connection that means after the user is logged out, the connection of the user's computer 2 to the respective designated login account 12 is interrupted. The interconnections of the login account 12 to the respective user accounts 101 , 111 , however, are maintained. This status is illustrated in FIG. 1C .
Usually, a server 1 only conducts a weak authentication by the means of requesting a user name and a password. The security achieved thereby is however low. In particular, attacks from outside and the access by non-authorized users can only be insufficiently prevented, wherein a user as soon as access had been granted via a designated login account 12 can have unrestraint access to the data 103 , 113 , can manipulate said data and in the worst case can influence the operation of the server 1 strongly.
In the embodiment illustrated in FIGS. 2A to 2D additionally to the previously described weak authentication an additional authentication step is therefore carried out, which is designated as strong authentication. In the embodiment illustrated in FIG. 2A to FIG. 2D the server 1 contains additionally a registry 14 in which user's computer specific identification data of the user's computer 2 and the designated user in form of reference listed are stored. The authentication for obtaining the connection of a user's computer 2 to the server 1 and for providing the service offered by the server 1 in form of data 103 , 113 is then carried out in the manner illustrated in FIG. 2A to FIG. 2D .
FIG. 2A shows the initial state before obtaining a connection. In this state no interconnections of the login accounts 12 to the designated user accounts 101 , 111 exist.
In a first step, the user obtains a connection to the designated login account 12 via a user's computer 2 and the interface 13 of the server 1 , wherein within a first authentication step a weak authentication is carried out by requesting a user's name and password. This is illustrated in FIG. 2B . In the illustrated example, a user obtains for instance a connection to the designated log in account 12 a via a user's computer 2 a.
In the status illustrated in FIG. 2B , the user's computer 2 is connected via the interface 13 to the server 1 and the designated login account 12 . The access to the data 101 , 113 is however not granted to the user, since interconnection of the login account 12 to the designated user accounts 101 , 111 has not yet been obtained.
In a second step, a so called strong authentication occurs now within which additional user's computer specific identification data are requested and are compared with identification data stored in advance in the registry 14 . The user's computer specific identification data can hereby be for instance additional personal information of a user, which the user transfers via the user's computer 2 to the server 1 . Alternatively, or additionally, also the network address (IP address or Mac address) of the user's computer 2 can be monitored within the user's computer specific identification data. This is based on the fact that a user shall only be granted access to the server 1 via a specific users computer 2 with a pre-determined network address. Furthermore, the identification of a pre-defined application program or a pre-defined time window can be used as additional user's computer specific identification data. Through this, access is allowed for the user only via a specific application program or only within a pre-defined time window.
If this second authentication is successful, the pre-defined connections of the login accounts 12 to the user accounts 101 , 111 are obtained. In the example illustrated in FIG. 2C the login account 12 a is for instance connected to the user account 101 a , while the login account 12 b is connected to the user accounts 101 b , 111 a . The user can therefore access the data 103 , 113 via the user accounts 101 , 111 and the designated scrollings 102 , 112 and can have the data 103 , 113 .
The second authentication step by the means of user's computer specific identification data stored in the registry 14 takes place via a server protection system installed on the server 1 . Thereby, it is of importance that the server 1 carries out at first the weak authentication for connecting a user's computer 2 to the designated login account 12 . Herewith, the authentication for the server 1 is finished. The connection of the user to the designated login account 12 is obtained. In this status the user, however, cannot access the data 103 , 113 since the interconnections between the login account 12 and the designated user accounts 101 , 111 have not yet been established. The further authentication is taken over by the server protection system via the registry 14 and the monitoring of the additional user's computer specific identification data; wherein in dependency on the monitoring of the respective login account 12 is connected to the designated user's accounts 101 , 111 . The authentication is therefore divided by two. After a first authentication step carried out by the server 1 a second authentication step occurs carried out by the server protection system by the means of the registry 14 , wherein in dependency on successful first and second authentication the access to the data 103 , 113 is granted.
If the first authentication of the server 1 for obtaining the connection of a user's computer 2 to the designated login account 12 via the interface 13 as well as the second authentication by monitoring the user's computer specific identification data are successful, then the interconnections of the login account 12 to the designated user's account 101 , 111 illustrated in FIG. 2C are obtained and the user can access the database 10 , 11 .
After closing the connection as illustrated in FIG. 2D on the one hand the connection between the user's computer 2 and the designated login account 12 is interrupted and simultaneously also any interconnection between the login account 12 and the user's account 101 , 111 is deleted. The interconnections between the login account 12 and the user's accounts 101 , 111 are therefore completely removed and are only obtained again by a renewed login and by successful renewed authentication.
Since an additional, also as strong named authentication is carried out by certifying the additional user's computer specific identification data, the safety for operating the server 1 is tremendously increased. Due to the additional certification of the user's computer specific identification data it is in particular prevented that non-authorized users can have access to server 1 . This guarantees that an access can for instance occur only via a pre-defined computer with a defined network address or via a specific application program. Furthermore, an access can also only be granted during specific times.
If the additional authentication is not successful, different measures can be taken. It is for instance conceivable that in case of non-successful authentication the access for a user is completely denied. If for instance the first authentication by requesting the user names and passwords already fails, the access for the user is completely denied. The same is true, if the first authentication is successful, but the additional authentication by requesting the user's computer specific identification data is not successful, for instance because the network address of the user's computer 2 via which the user tries to access the server 1 does not match a network address stored in advance.
Instead of denying access, however, also less rigid measures are conceivable. For instance a user can be granted access despite unsuccessful authentication, wherein the user is however provided with other than the desired data (so-called honey pot). It is also conceivable to grant the access and provide the correct desired data, however the user is put under surveillance, i.e. his actions are monitored in a specific manner. Alternatively, it is again conceivable not to grant the access at first and request further identification data for further authentication and only in dependency on this further authentication to grant the access or finally to deny access.
The user's computer specific identification data, which shall be requested in case of the additional authentication, can be detected in a detection phase before the actual operation of the server 1 and can be stored in the registry 14 . In the detection phase for instance the network address and the application program to be used are determined and are deposited in the registry 14 , wherein in the latter operation phase during the actual operation of the server 1 an access to the server 1 is only possible via the user's computer 2 defined in advance with the pre-defined network address and the pre-defined application program. In the detection phase the server protection system can also work in the background, wherein no or at least no complete strong authentication is carried out. In an operation phase after finishing the detection phase an access is then only granted in dependency on a successful authentication in the above described manner.
An additional protection can be achieved, if a user is granted access only to the server exclusively via a pre-defined application program. If the application program is thereby conducted on the user's computer 2 by the means of an application protection system, then it is excluded right from the beginning that a non-authorized user can access the server 1 via any user's computer and any application program.
FIG. 3 shows a schematic view of an application program 24 installed on a users computer 2 . Thereby, a protection wall 21 (fire wall) as well as a virus scanner 22 are installed on the user's computer 2 , which prevent an access from the outside to the user's computer 2 as well as a manipulation by a harmful software as far as possible in a known manner. In addition, an application protection system 23 with an administration module 230 and a running time monitor 231 is installed on the user's computer 2 , which monitor the starting and the conducting of the application program 24 .
The administration module 230 of the application protection system 23 serves the administration. The administration module 230 detects thereby in an initialization phase all system files of the user's computer 2 and stores the file in a registry in form of a reference list. The administration module 230 detects thereby for each system file and each module an identification, for instance in form of a cryptographic hash value or a digital signature, and deposits them in the registry. An identification of the application program 24 to be put under protection is then told to the administration module 230 , whereupon the administration module 230 detects for the application program 24 the system files and the modules of the user's computer 2 , to which the application program 24 has access. In turn, the administration module 230 detects for each such detected system file an identification and stores these together with the identification of the application programs 24 in a separated registry.
It is additionally determined that the starting of the application program 24 can exclusively occur via the administration module 230 . Herewith, each attempt to start the application program 24 not via the administration module 230 is excluded right from the beginning.
The application program 24 is started via the administration module 230 for carrying out the said application program. The conduction of the application program 24 is then monitored by the running time monitor 231 , wherein the running time monitor 231 compares at first the identification of the application program 24 with the identification of the application program 24 stored in advance by the administration module 230 in the registry. Only if this identification matches then the starting and conducting of the application program 24 is permitted.
The running time monitor 231 generates a protection object 25 in form of an operating system object and provides them specific protection properties. The application program 24 is conducted in this protection object 25 , wherein the protection object 25 isolates the application program 24 from all other programs and processes of the user's computer 2 and makes any contact to the application program 24 from the outside impossible. The protection object 25 has thereby an exclusive set of operating means, for instance a specific keyboard or a specific monitor via which the application program 24 can be controlled.
The application program 24 is conducted in the protection object 24 until it is finished. After finishing the application program 24 the protection object 25 is completely removed.
During the time of conduction of the application program 24 the running time monitor 231 monitors each request of the application program 24 to a system file or a module of the user's computer 2 and certifies, if the identification of the system file or the module is present in the registry stored in advance by the administration module 230 within the initialization phase. The time running monitor 231 certifies thereby, if the identification of the system file is contained in the registry of all system files of the user's computer 2 or in the registry of the system files or modules designated to the application program 24 . If the requested system file is not in one or in both of the registries, the conduction of the application program 24 is interrupted. If the system file is in both registries, then the requested system file or the requested module is approved and the conduction of the application program 24 is continued.
The conduction of an application program 24 is monitored and controlled by the means of the application protection system 23 and in this manner protected from attacks from outside, for instance by a harmful software. Simultaneously, a version and license control can be carried out by the application protection system 23 by checking for instance during conduction if the application program 24 is conducted using a valid license number.
In a preferred embodiment the application protection system 23 of the user's computer 2 and the server protection system of the server 1 work together. The application protection system 23 communicates hereby with the server 1 , wherein the server 1 and the application protection system 23 authenticate each other. The communication can occur for instance via the ISO/IEC 9798-3-standard. The application protection system contacts thereby in a first step the server 1 . In a second step, the application protection system 23 and the server 1 conduct a mutual authentication, wherein by the mutual authentication the server 1 knows on the one hand that the application program 24 is not being manipulated, and on the other hand, the user's computer 2 can be sure to communicate with the correct server 1 .
The communication between server 1 and user's computer 2 in the previously described examples occurs preferably via the internet, which is a communication network for data exchange between different computers and computer systems as known.
The idea forming the basis of the invention is not restricted to the previously described embodiments, but can also be realized by completely different embodiments. The described protection system is in particular not restricted to the application for a database server, but can also be used in general for protecting a server. Furthermore, the described system can also be used as a forensic means in order to analyze infringements of access regulations. | The invention relates to a server system for providing at least one service. The system having an interface for connecting a server to a user's computer, an authentication device that is designed and provided for request personal identification data of a user who logs onto the server via the user computer and to permit the user computer access if authentication is successful, and a server protection system. The server protection system is designed and provides to compare additional user's computer specific identification data with identification data stored in advance on the server, after successful authentication by the authentication device, and to grant authorization to the user's computer to access the service or services depending on the comparison of the user's computer specific identification data. The invention also relates to a method for providing at least one service and the method for executing an application program. | 6 |
The present application claims the benefit of German Patent Application Serial Number 102010046536.4, filed Sep. 27, 2010 and German Patent Application Serial Number 102010054341.1, filed Dec. 13, 2010.
FIELD OF THE INVENTION
The invention relates to a process for applying a fire-protection coating to a substrate, and also to a substrate thus coated.
BACKGROUND OF THE INVENTION
In the fitting-out of internal spaces, wood surfaces, in particular wood veneers, are often used on cladding, furniture, or the like. The coating here is intended firstly to improve the appearance of the surface and secondly to provide protection, for example from mechanical stresses. In particular instances, this type of coating also has the function of improving fire protection.
By way of example, when furniture or cladding is installed into the interior of an aircraft there is a need to comply with fire-performance requirements under air traffic legislation. A component of this type is subjected, for example, to a Bunsen burner fire test with 60 s of exposure to a flame at a temperature of 860° C. Extinguishment of the component must occur within 15 s after the end of flame application. The distance between the point of flame application and the most distant point burnt by the flame on the surface of the specimen is not permitted to be more than 155 mm (FAA CS 25.853 (a)).
From public prior use, it is known that wood can be provided with flame-retardant impregnation. A disadvantage here is that this type of impregnation can discolor the wood and sometimes acts as plasticizer within a clearcoat layer subsequently applied. There can also be impairment of adhesion of a coating layer on the impregnated surface. It is also known from public prior use that clearcoat can be provided with chemical fire-protection compositions. Here again, a disadvantage is that discoloration of the wood surface can occur, and that the flame retardants can have an undesirable plasticizing effect.
SUMMARY OF THE INVENTION
It is an object of the invention to provide a process and a coated substrate of the type mentioned in the introduction, where these combine good surface properties with good fire protection.
The process of the invention achieves said object via the following steps:
a) applying a first clearcoat layer to the substrate; b) applying an intumescent fire-protection layer to the first clearcoat layer; c) applying a second clearcoat layer to the intumescent fire-protection layer.
DESCRIPTION OF THE DRAWING
FIG. 1 shows a representation of a cross-sectional view of a substrate having a veneer surface and a first clearcoat layer, a fire-protection layer, and a second clearcoat layer.
DEFINITIONS
Some terms used for the purposes of the invention will first be explained. A substrate is by way of example a piece of furniture, a wall cladding, or the like. Preference is given to a substrate with a wood surface.
The substrate can have been manufactured from solid wood, or can preferably be composed of a wood veneer on a supportive structure. The supportive structure can comprise a particle board, a sandwich structure, or the like.
The term clearcoat designates a coating which is in essence transparent and which does not hide a structure located thereunder, for example woodgrain.
DESCRIPTION OF THE INVENTION
An intumescent fire-protection layer is applied as intermediate layer on said first clearcoat layer. An intumescent fire-protection layer comprises substances which increase their volume on exposure to heat and thus have a flame-retardant effect. Intumescent fire-protection mixtures which are suitable for producing an appropriate coating are disclosed by way of example in DE 197 51 434 A1.
In the invention, a second clearcoat layer is applied to the intumescent fire-protection layer. The first and second clearcoat layer can also be applied in a plurality of respective individual layers for the purposes of the invention.
The invention thus permits both that region of the entire coating that faces toward the substrate and that region that faces toward the exterior surface to have the properties of the clearcoat used, so that the resistance of the surface to exterior stresses and the interaction with the substrate are determined entirely via the properties of the clearcoat. The intumescent fire-protection layer has been inserted rather in the manner of a sandwich between two clearcoat layers and cannot therefore have any disadvantageous effect either on the surface properties of the entire coating or on the interaction with the substrate (in particular wood). Design of the fire-protection layer in the form of intumescent layer also permits achievement of particularly good flame retardancy.
It is preferable that the first and/or second clearcoat layer have been selected from the group consisting of polyurethane coatings, polyester coatings, and poly(meth)acrylate coatings. These comprise coatings which are in particular used for coating of wood and of wood veneer surfaces in the prior art.
Hardening of polyurethane coatings occurs via reaction of polyisocyanates with hydroxylated compounds. The hydroxy component can by way of example comprise polyesters, polyethers, or acrylic resins. Polyester coatings usually cure via polyaddition of unsaturated compounds. The same applies to poly(meth)acrylates. Examples of suitable coatings are described in Ullmann's Encyclopedia of Industrial Chemistry, 6 th edition, volume 24, pp. 594 (Paints and Coatings); and volume 39, pp. 515 (Wood, surface treatment) specifically for wood surfaces. The cited disclosure is also incorporated within the subject matter of the present application.
The intumescent fire-protection layer in the invention can comprise an intumescent synthetic resin. An intumescent synthetic resin based on melamine/formaldehyde resin is particularly suitable. The intumescent fire-protection layer can also in particular comprise flame-retardant compounds, such as phosphoric ester. Suitable intumescent compositions are described by way of example in DE 197 51 434 A1, the disclosure of which is incorporated by way of reference. Intumescent fire-protection mixtures of this type are available commercially by way of example from AISCO Chemieprodukte GmbH as K1+K2 2-Component Fire Protection System.
The intumescent fire-protection layer can be applied in the invention with a thickness of from 40 to 200 μm, preferably from 60 to 120 μm, in particular by way of example approximately 80 μm.
The clearcoat layers and/or the intumescent fire-protection layer is/are preferably applied by spraying, in particular with a spray gun. Application by spraying can give a high-quality coating. Intumescent fire-protection compositions of the prior art are generally applied by way of example with a spreader. They are generally intended for fire protection on articles where visual quality of the surface is not critical.
In the invention it is preferable to adjust the viscosity of the intumescent mixture for producing an intumescent fire-protection coating of the invention in such a way as to permit application by a spray gun. Mixtures suitable for application by a spray gun are generally those of viscosity 16 s (45 mm 2 /s) or greater (measured to DIN 53211 with a 4 mm flow cup). Preferred viscosity ranges are from 16 to 100 s (45 to 452 mm 2 /s), preferably from 17 to 80 s (51 to 360 mm 2 /s), more preferably from 19 to 60 s (63 to 267 mm 2 /s). The viscosity can be adjusted with a suitable solvent, such as water.
The intumescent fire-protection layer can comprise an additive for compatibilization with the clearcoat layers. Examples of suitable compounds for compatibilization of intumescent fire-protection compositions based on melamine/formaldehyde with polyurethane clearcoats are polyether siloxanes, which are added at a concentration of, for example, about 1% by weight to the intumescent fire-protection composition.
Appropriate polyether siloxanes are obtainable by way of example from Evonik as TEGO Wet 270.
The invention further provides a substrate with a fire-protection coating, wherein the coating comprises:
a) a first clearcoat layer on the substrate; b) an intumescent fire-protection layer on the first clearcoat layer; c) a second clearcoat layer on the intumescent fire-protection layer.
The invention further provides a substrate with a fire-protection coating, obtainable via a process of the invention.
An example of the invention is explained below, using the drawing, which is a diagram of the structure of a substrate coated in the invention.
The substrate used comprises a honeycomb sandwich panel with maple veneer adhesively bonded thereto.
The clearcoat layer is produced by using Crystallites® 2K PUR Top-Klarlack from Zweihorn. The manufacturer's instructions indicate that coating component and hardener component are used in a ratio by weight of 10:1.
The intumescent fire-protection mixture used comprises the K1+K2 2-Component Fire Protection System from AISCO Chemieprodukte GmbH. The manufacturer's instructions indicate that component K1 and component K2 are mixed in a ratio by weight of 6:4. Viscosity is then adjusted appropriately via dilution with 20% by weight of water, and 1% by weight of TEGO Wet 270 additive from Evonik (polyether siloxane) is incorporated by mixing.
The first clearcoat layer is applied by spraying onto the wood veneer of the sandwich panel until a closed-pore surface is produced. Once the material has been permitted to harden, said first clearcoat layer is subjected to an appropriate degree of abrasion, and then the intumescent fire-protection layer is applied by spraying at a thickness of 80 μm. This is likewise permitted to harden, and is subjected to an appropriate degree of abrasion. Once said intumescent fire-protection layer has been subjected to an appropriate degree of abrasion and thus activated, the second clearcoat layer is applied in two spray passes thereto.
A further inventive example is explained below.
The substrate used comprises a sheet of solid maple wood.
The clearcoat layer is produced by using Duritan® Two-Pack Pore Surfacer, Duritan® Three-Pack High-Solid Filling Primer, and Duritan® Three-Pack High-Solid High-Gloss Varnish from Zweihorn. The manufacturer's instructions indicate that component A and component B of the Pore Surfacer are used in a ratio by weight of 1:1, and coating component, hardener component, and activator component of the Filling Primer and of the High-Gloss Varnish are used in a ratio by weight of 100:100:2.
The intumescent fire-protection mixture used comprises the pyroplast-HW 300 fire-protection system from RÜTGERS Organics GmbH. The manufacturer's instructions indicate that component K1 and component K2 are mixed in a ratio by weight of 6:4.
Viscosity is then adjusted appropriately via dilution with 30% by weight of water, and 1% by weight of TEGO Wet 270 additive from Evonik (polyether siloxane) is incorporated by mixing.
The Duritan® Two-Pack Pore Surfacer is applied to the wood substrate in order to fill the pores of the wood. After curing via excitation with UV radiation, Duritan® Three-Pack High-Solid Filling Primer is applied by spraying until a closed-pore surface is produced. Layers of wet thickness 100 μm are applied here and are individually hardened via UV excitation. Said clearcoat layer is leveled by abrasion, and the intumescent fire-protection layer is then applied by spraying, at a wet thickness of 100 μm. This is permitted to harden via air-drying, and is subjected to an appropriate degree of abrasion. Once said intumescent fire-protection layer has been subjected to an appropriate degree of abrasion and thus activated, a further clearcoat layer made of Duritan® Three-Pack High-Solid Filling Primer is applied in two spray passes thereto. Finally, once the coating has been leveled by fine abrasion a final coating of Duritan® Three-Pack High-Solid High-Gloss Varnish is applied. After hardening via excitation with UV light, the final coating layer is polished to give high gloss: 90 gloss units.
The adhesion of the coating of the invention to DIN EN ISO 4624 is about 2 MPa.
The fire test described in the introduction to the description is found in the standard FAA CS 25.853 (a). When the coating of the invention is subjected to this test, the afterflame time is 0 s and the burnt section measures 85 mm. | The invention relates to a process for applying a fire-protection coating to a substrate using a process comprising the steps of applying a first clearcoat layer to the substrate, applying an intumescent fire-protection layer to the first clearcoat layer, and applying a second clearcoat layer to the intumescent fire-protection layer. | 8 |
FIELD OF THE INVENTION
[0001] This invention relates generally to the treatment of viral infections, and more specifically to the treatment of viral infections with phospholipids and phospholipid derivatives.
BACKGROUND OF THE INVENTION
[0002] A current treatment for combating human immunodeficiency virus type 1 (HIV-1) infections is the administration of the nucleoside analog 3′-azido-3′-deoxythymidine (AZT) to an afflicted subject. See, e.g., U.S. Pat. No. 4,724,232 to Rideout et al. HIV-1 infection treatment methods have also included the administration of ether lipid compounds in an amount effective to inhibit replication of the virus in infected cells, see e.g., Kucera et al., AIDS Research and Human Retroviruses 6:491 (1990), and ether lipids conjugated with AZT and other antiviral nucleoside analogs. See PCT Application No. US91/04289 (published 26 Dec. 1991). These compounds appear to act at the plasma membrane to block the endocytic process of HIV-1 into CD4 + cells and the process of virus assembly, cell fusion and pathogenesis. They also can inhibit the activity of protein kinase C. Given the seriousness of HIV-1 infection worldwide, there is an ongoing need for new methods of combating HIV-1 infections.
[0003] Another virus of serious concern, hepatitis B virus (HBV), is one of a family of hepadnaviruses that cause acute and chronic liver disease, including liver cancer. HBV, which is found in the body fluids of infected persons, makes three antigenic proteins during multiplication in liver cells: hepatitis B surface antigen (HBsAg), hepatitis B e antigen (HBeAg) and hepatitis B core antigen (HBcAg). These three virus antigenic proteins are important as markers for determining virus infection, as antibodies against the virus infection are made in response to these virus proteins in the blood. An HBV vaccine is available to prevent infection, and hyperimmune gamma globulin is available for temporary prophylaxis against developing HBV infection in persons at risk. Clearly specific antiviral agents are needed for treatment and control of HBV infections in humans.
[0004] Based on the foregoing, it is an object of the present invention to provide a new treatment method for combating the effects of HIV-1.
[0005] It is another object of the present invention to provide compounds and pharmaceutical compositions for carrying out HIV-1 treatment methods.
[0006] It is also an object of the present invention to provide a new treatment method for combating the effects of HBV.
[0007] It is a second object of the present invention to provide compounds and pharmaceutical compositions for carrying out HBV treatment methods.
SUMMARY OF THE INVENTION
[0008] These and other objects are satisfied by the present invention, which provides methods of combating viral infections. As a first aspect, the present invention provides a method of combating a viral infection in a subject in need of such treatment comprising administering to the subject an effective infection-combating amount of a compound of Formula I or a pharmaceutical salt thereof.
[0009] In the compounds of Formula I, R 1 is a branched or unbranched, saturated or unsaturated C 6 to C 18 alkyl group optionally substituted from 1 to 5 times with —OH, —COOH, oxo, amine, or substituted or unsubstituted aromatic; X is selected from the group consisting of NHCO, CH 3 NCO, CONH, CONCH 3 , S, SO, SO 2 , O, NH, and NCH 3 ; R 2 is a branched or unbranched, saturated or unsaturated C 6 to C 14 alkyl group optionally substituted from 1 to 5 times with —OH, —COOH, oxo, amine, or substituted or unsubstituted aromatic; Y is selected from the group consisting of NHCO, CH 3 NCO, CONH, CONCH 3 , S, SO, SO 2 , O, NH, and NCH 3 ; R 6 is a branched or unbranched C 2 to C 6 alkyl group; and R 3 , R 4 , and R 5 are independently methyl or ethyl, or R 3 and R 4 together form an aliphatic or heterocyclic ring having five or six members and R 5 is methyl or ethyl. Preferred compounds include 1-dodecanamido-2-decyloxypropyl-3-phosphocholine, 1-dodecanamido-2-octyloxypropyl-3-phosphocholine, and 1-dodecanamido-2-dodecyloxypropyl-3-phosphocholine. The method is particularly preferred as a treatment to combat viral infections caused by HIV-1, HBV, and herpes simplex virus. The present invention also includes pharmaceutical compositions comprising a compound of Formula I and a suitable pharmaceutical carrier.
[0010] As a second aspect, the present invention includes a method of combating viral infections in a subject in need of such treatment which comprises the administration to such a subject a compound of Formula II or a pharmaceutical salt thereof in an effective infection-combating amount.
[0011] In Formula II, the ring structure is optionally substituted from 1 to 3 times with C 1 to C 3 alkyl; R 1 is an unbranched or branched, saturated or unsaturated C 6 to C 20 alkyl group; R 2 , R 3 , and R 4 are independently methyl or ethyl, or R 2 and R 3 together form an aliphatic or heterocyclic ring having five or six members and R 4 is methyl or ethyl; X is selected from the group consisting of NHCO, CH 3 NCO, CONH, CONCH 3 , S, SO, SO 2 , O, NH, and NCH 3 ; R 5 is a branched or unbranched C 2 to C 6 alkyl group; m is 1 to 3; and n is 0 to 2. Preferred compounds of Formula II are 3-hexadecanamido-cyclohexylphosphocholine and 3-hexadecylthio-cyclohexylphosphocholine. Adminstration of the compounds of Formula II is particularly useful in treating viral infections caused by HIV-1, HBV, and herpesviruses. The present invention also includes pharmaceutical compositions comprising a compound of Formula II and a suitable pharmaceutical carrier.
[0012] A third aspect of the present invention is a method of treating viral infections comprising administering to a subject in need of such treatment an effective infection-inhibiting amount of a compound of Formula III.
[0013] In compounds of Formula III, R 1 is a branched or unbranched, saturated or unsaturated C 6 to C 18 alkyl group optionally substituted from 1 to 5 times with —OH, —COOH, oxo, amine, or substituted or unsubstituted aromatic; X is selected from the group consisting of NHCO, CH 3 NCO, CONH, CONCH 3 , S, SO, SO 2 , O, NH, and NCH 3 ; R 2 is a branched or unbranched, saturated or unsaturated C 6 to C 14 alkyl group optionally substituted from 1 to 5 times with —OH, —COOH, oxo, amine, or substituted or unsubstituted aromatic; Y is selected from the group consisting of NHCO, CH 3 NCO, CONH, CONCH 3 , S, SO, SO 2 , O, NH, and NCH 3 ; and Z is a moiety of the Formula V,
[0014] wherein:
[0015] V is H or N 3 ;
[0016] W is H or F; or
[0017] V and W together are a covalent bond; and
[0018] B is a purinyl moiety of Formula VI
[0019] optionally substituted at position 2 with ═O—OH, —SH, —NH 2 , or halogen, at position 4 with NH 2 or ═O, at position 6 with Cl, —NH 2 , —OH, or C 1 -C 3 alkyl, and at position 8 with Br or I; or
[0020] B is a pyrimidinyl moiety of Formula VII
[0021] substitued at position 4 with ═O or NH 2 and optionally substituted at position 5 with halogen or C 1 -C 3 saturated or unsaturated alkyl optionally substituted 1 to 3 times with halogen.
[0022] Pharmaceutical compositions comprising these compounds and a pharmaceutical carrier are also encompassed by the present invention.
[0023] A fourth aspect of the present invention is a method of inhibiting viral infections comprising administering to a subject in need of such treatment an effective infection-inhibiting amount of a compound of Formula IV.
[0024] In the compounds of Formula IV, the ring structure is optionally substituted from 1 to 3 times with C 1 to C 3 alkyl; R 1 is an unbranched or branched, saturated or unsaturated C 6 to C 20 alkyl group; X is selected from the group consisting of NHCO, CH 3 NCO, CONH, CONCH 3 , S, SO, SO 2 , O, NH, and NCH 3 ; m is 1 to 3; n is 0 to 2; and Z is a moiety of the Formula V,
[0025] wherein:
[0026] V is H or N 3 ;
[0027] W is H or F; or
[0028] V and W together are a covalent bond; and
[0029] B is a purinyl moiety of Formula VI
[0030] optionally substituted at position 2 with ═O—OH, —SH, —NH 2 , or halogen, at position 4 with NH 2 or ═O, at position 6 with Cl, —NH 2 , —OH, or C 1 -C 3 alkyl, and at position 8 with Br or I; or
[0031] B is a pyrimidinyl moiety of Formula VII
[0032] substitued at position 4 with ═O or NH 2 and optionally substituted at position 5 with halogen or C 1 -C 3 saturated or unsaturated alkyl optionally substituted 1 to 3 times with halogen.
[0033] The present invention also includes pharmaceutical compositions comprising a compound of Formula IV and a suitable pharmaceutical carrier.
DETAILED DESCRIPTION OF THE INVENTION
[0034] As used herein, the term “alkyl” is intended to refer to an unbranched or branched alkyl group comprising carbon atoms, such as methyl, ethyl, propyl, isopropyl, n-butyl, tert-butyl, hexyl, and octyl. The term “pharmaceutical salt” refers to a salt that retains the desired biological activity of the parent compound and does not impart undesired toxicological effects thereto. Examples of such salts are (a) salts formed with cations such as sodium, potassium, NH 4 + , magnesium, calcium polyamines, such as spermine, and spermidine, etc.; (b) acid addition salts formed with inorganic acids, for example hydrochloric acid, hydrobromic acid, sulfuric acid, phosphoric acid, nitric acid and the like; (c) salts formed with organic acids such as, for example, acetic acid, oxalic acid, tartaric acid, succinic acid, maleic acid, fumaric acid, gluconic acid, citric acid, malic acid, ascorbic acid, benzoic acid, tannic acid, palmitic acid, alginic acid, polyglutamic acid, naphthalenesulfonic acid, methanesulfonic acid, p-toluenesulfonic acid, naphthalenedisulfonic acid, polygalacturonic acid, and the like; and (d) salts formed from elemental anions such as chlorine, bromine, and iodine.
[0035] A first aspect of the present invention is a method of combating viral infection comprising administering a compound of Formula I, wherein R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , X, and Y are defined as stated above, or a pharmaceutical salt thereof. The amphipathic compounds of Formula I, which are generally analogs of phosphatidylcholine, include a glycerol backbone (represented by the chain of three carbon atoms to which other functional groups are bonded), lipophilic moieties (represented by R 1 and R 2 ) bonded to positions 1 and 2 of the glycerol backbone through functional groups (represented by X and Y) that are generally resistant to phospholipase degradation, and polar phosphate and quaternary amine groups (linked to one another through a short alkyl group) bonded to position 3 of the glycerol backbone. Each of these components of the compounds of Formula I is described separately below.
[0036] In Formula I, as described above, R 1 is a lipophilic moiety; the lipophilicity of R 1 allows the compounds of Formula I to bind with the cell membrane of a cell infected with a retrovirus to provide an anchor thereto. R 1 can be an unbranched or branched, saturated or unsaturated C 6 to C 18 alkyl group. Preferably, R 1 is an unbranched saturated or unsaturated C 8 to C 12 alkyl group, and more preferably, R 1 is an unbranched saturated C 10 or C 12 alkyl group.
[0037] In compounds of Formula I, X is a functional group that links the lipophilic moiety R 1 and the glycerol backbone of the compound. X is selected from the group consisting of NHCO, CH 3 NCO, CONH, CONCH 3 , S, SO, SO 2 , O, NH, and NCH 3 ; these functional groups are resistant to the hydrolytic activity of cellular lipases, in particular phospholipase A, which is specific for ester linkages at position 1 (as are present in phosphatidyl choline). Preferably, X is S or NHCO, with NHCO being most preferred.
[0038] In Formula I, R 2 is a lipophilic moiety which, as is true for R 1 , enables the compounds of Formula I to bind with the cell membrane of an infected cell. R 2 can be an unbranched or branched, saturated or unsaturated C 6 to C 14 alkyl group. Preferably, R 2 is an unbranched saturated or unsaturated C 8 to C 12 alkyl group, and more preferably, R 2 is an unbranched saturated C 8 or C 10 alkyl group. It is also preferred that R 1 and R 2 together contain between 18 and 22 carbon atoms.
[0039] R 2 is bonded to position 2 of the glycerol backbone through a functional group Y, which is selected from the group consisting of NHCO, CH 3 NCO, CONH, CONCH 3 , S, SO, SO 2 , O, NH, and NCH 3 . Like X, Y should be a moiety that is resistant to the hydrolytic activity of cellular lipases, and in particular phospholipase B, as this enzyme is specific for ester linkages at position 2. Preferably, X is S or O, with O being more preferred.
[0040] The polar hydrophilic end of the amphipathic compounds of Formula I, which can play a role in membrane interaction, comprises an amphoteric phosphoalkyl quaternary amine group in which the phosphate moiety carries the negative charge and the quaternary amine moiety carries the positive charge. In this group, R 6 , which is a branched or unbranched, saturated or unsatured C 2 to C 6 alkyl group, is preferably saturated C 2 . R 3 , R 4 , and R 5 are independently selected from the group consisting of methyl and ethyl, with methyl being preferred, and with R 3 , R 4 , and R 5 each being methyl being more preferred, or R 3 and R 4 together form an aliphatic or heterocyclic ring having five or six members and R 5 is methyl or ethyl.
[0041] Exemplary compounds of Formula I include 1-dodecanamido-2-decyloxypropyl-3-phosphocholine (CP-128), 1-dodecanamido-2-octyloxypropyl-3-phosphocholine (CP-130), 1-dodecanamido-2-dodecyloxypropyl-3-phosphocholine (CP-131), and 1-dodecyloxy-2-decyloxypropyl-3-phosphocholine (CP-1 29). These compounds of Formula I can be synthesized according to the procedures set forth in Examples 1 and 2 below. Other compounds of Formula I can be synthesized using the same method with the appropriate reagents substituted for those listed.
[0042] Another aspect of the invention is a method of combating viral infection by administering compounds of Formula II, wherein R 1 , R 2 , R 3 , R 4 , R 5 , X, m, and n are defined as stated above, or a pharmaceutical salt thereof. Compounds of Formula II are amphipathic moieties having a lipophilic moiety (represented by R 1 ) linked to a five- or six-membered ring structure (which is optionally sustituted 1 to 3 times with C 1 to C 3 alkyl) and a hydrophilic moiety that includes phosphate and quaternary amine groups linked by a short alkyl group that is bonded to the ring structure through the phosphate group. The hydrophilic group is linked to the ring at position 1, and the lipophilic group is linked to the ring at positions 2, 3, or 4. Like the compounds of Formula I, the compounds of Formula II are analogs of phosphatidyl choline. However, the ring structure provides a more conformationally restricted framework for the compound than compounds lacking a ring structure; this restricted framework can provide the compound with more favorable interaction with the cellular membrane and thereby increase its efficacy.
[0043] In the compounds of Formula II, R 1 can be an unbranched or branched, saturated or unsaturated C 6 to C 20 alkyl group. As with the compounds of Formulas II, R 1 is a lipophilic moiety which binds with the cell membrane of infected cells to provide an anchor thereto. Preferably, R 1 is unbranched saturated or unsaturated C 10 to C 18 alkyl. More preferably, R 1 is unbranched saturated or unsaturated C 16 to C 18 alkyl.
[0044] In compounds of Formula II, X is a functional group that links the lipophilic moiety R 1 to position 1 of the ring structure. X should be a functional group, such as NHCO, CH 3 NCO, CONH, CONCH 3 , NH, NCH 3 , S, SO, SO 2 , or O, that is able to withstand the hydrolytic activity of cellular lipases. Preferably, Y is S or NHCO.
[0045] As stated above, the polar hydrophilic end of the amphipathic compounds of Formula II comprises a phosphate group bonded to the ring structure, a short alkyl group R 5 linked at one end thereto, and a quaternary amine group linked to the opposite end of the short alkyl group. R 5 is a saturated or unsaturated, branched or unbranched C 2 to C 6 alkyl group, and is more preferably C 2 . R 2 , R 3 , and R 4 are independently selected from the group consisting of methyl and ethyl, with methyl being preferred, or R 2 and R 3 together form an aliphatic or heterocyclic five- or six-membered ring structure and R 4 is methyl or ethyl. It is more preferred that R 2 , R 3 , and R 4 are each methyl.
[0046] In the compounds of Formula II, m can be 1, 2, or 3, and n can be 0, 1, or 2. Preferably the ring structure is a five- or six-membered ring; thus, preferably m is 2 or 3 when n is 0, m is 1 or 2 when n is 1, and m is 1 when n is 2. As noted above, the ring structure provides conformational rigidity to the compound.
[0047] Exemplary compounds of Formula II include 3-hexadecylthio-cyclohexylphosphocholine (INK-1), 3-hexadecanamido-cyclohexylphosphocholine, 3-hexadecanamido-cyclopentylphosphocholine, and 3-hexadecylthio-cyclopentylphosphocholine. These compounds of Formula II can be synthesized by following the teachings of Example 3 below in combination with procedures known to those skilled in the art.
[0048] An additional aspect of the present invention is a method of combating viral infection with compounds of Formulas III and IV. These compounds substitute a moiety Z for the alkyl-quaternary amine of the compounds of Formulas I and II, wherein Z is as defined above. Z is a moiety that has demonstrated anti-viral activity by itself; thus conjugation of Z to the remainder of the compounds of Formulas III and IV provides a compound that potentially includes multiple active sites for viral inhibition.
[0049] In the compounds of Formula III, R 1 , R 2 , X and Y are defined above. R 1 is a lipophilic moiety; the lipophilicity of R 1 allows the compounds of Formula I to bind with the cell membrane of a cell infected with a retrovirus to provide an anchor thereto. R 1 can be an unbranched or branched, saturated or unsaturated C 6 to C 18 alkyl group. Preferably, R 1 is an unbranched saturated or unsaturated C 8 to C 12 alkyl group, and more preferably, R 1 is an unbranched saturated C 10 or C 12 alkyl group.
[0050] In compounds of Formula III, X is a functional group that links the lipophilic moiety R 1 and the glycerol backbone of the compound. X is selected from the group consisting of NHCO, CH 3 NCO, CONH, CONCH 3 , S, SO, SO 2 , O, NH, and NCH 3 ; these functional groups are resistant to the hydrolytic activity of cellular lipases, in particular phospholipase A, which is specific for ester linkages at position 1 (as are present in phosphatidyl choline). Preferably, X is S or NHCO, with NHCO being most preferred.
[0051] In Formula III, R 2 is a lipophilic moiety which, as is true for R 1 , enables the compounds of Formula III to bind with the cell membrane of an infected cell. R 2 can be an unbranched or branched, saturated or unsaturated C 6 to C 14 alkyl group. Preferably, R 2 is an unbranched saturated or unsaturated C 8 to C 12 alkyl group, and more preferably, R 2 is an unbranched saturated C 8 or C 10 alkyl group. It is also preferred that R 1 and R 2 together contain between 18 and 22 carbon atoms.
[0052] R 2 is bonded to position 2 of the glycerol backbone through a functional group Y, which is selected from the group consisting of NHCO, CH 3 NCO, CONH, CONCH 3 , S, SO, SO 2 , O, NH, and NCH 3 . Like X, Y should be a moiety that is resistant to the hydrolytic activity of cellular lipases, and in particular phospholipase B, as this enzyme is specific for ester linkages at position 2. Preferably, X is S or O, with O being more preferred.
[0053] In the compounds of Formula III, Z is a moiety of Formula V. Moieties of Formula V are intended to be anti-viral agents, and thus potentially provide an additional active site for anti-viral activity that may act through a different mechanism. In the moieties of Formula V, V is H, or N 3 , or V and W together from a covalent bond with H and N 3 being preferred. W is H or F, with H being preferred.
[0054] In the compounds of Formula III, B is a purinyl moiety of Formula VI or a pyrimidinyl moiety of Formula VII, each of which are substituted as described above. As used herein, a purinyl moiety comprises six- and five-membered aromatic rings having the molecular structure illustrated in Formula VI. Those skilled in this art will appreciate that the double bonds illustrated in Formula VI are present to represent that the purinyl moieties have aromatic character, and that these double bonds may shift their positions in certain compounds due to the presence of certain substituents to retain the aromatic character of the moiety; in particular, those moieties having ═O or NH 2 substituents at positions 2 and 4, such as adenine, guanine, xanthine, and hypoxanthine, are generally illustrated as having double bonds shifted from the positions shown in Formula VI. Similarly, as used herein a pyrimidinyl moiety comprises a six-membered aromatic ring having the molecular structure illustrated in Formula VII. Those skilled in this art will appreciate that the double bonds illustrated in Formula VII are included therein to represent that the moieties of Formula VII have aromatic character, and that these double bonds may shift for certain substituents, in particular for ═O and NH 2 at positions 2 and 4, in order for the moiety to retain its aromatic character. Preferably, B is selected from the group consisting of adenine, thymine, cytosine, guanine, hypoxanthine, uracil, 5-fluorouracil, 2-fluoro-adenine, 2-chloro-adenine, 2-bromo-adenine, and 2-amino-adenine.
[0055] Preferably, Z is 3′-azido-3′-deoxythymidine, dideoxyinosine, dideoxycytidine, or 2′, 3′-didehydro-3′-deoxythymidine. An exemplary preferred compound of Formula III is 3′-azido-3′-deoxy-5′-(3-dodecanamido-2-decyloxypropyl)-phosphothymidine.
[0056] A further aspect of the present invention is a method of inhibiting viral infections comprising administering to a subject an effective infection-inhibiting amount of a compound of Formula IV, wherein R 1 , R 2 , X, m, n, and Z are as defined above. In the compounds of Formula IV, R 1 can be an unbranched or branched, saturated or unsaturated C 6 to C 20 alkyl group. As with the compounds of Formula II, R 1 is a lipophilic moiety which binds with the cell membrane of infected cells to provide an anchor thereto. Preferably, R 1 is unbranched saturated or unsaturated C 10 to C 18 alkyl. More preferably, R 1 is unbranched saturated or unsaturated C 16 to C 18 alkyl.
[0057] In compounds of Formula IV, X is a functional group that links the lipophilic moiety R 1 to position 1 of the ring structure. X should be a functional group, such as NHCO, CH 3 NCO, CONH, CONCH 3 , NH, NCH 3 , S, SO, SO 2 , or O, that is able to withstand the hydrolytic activity of cellular lipases. Preferably, X is S or NHCO.
[0058] As stated above, the polar hydrophilic end of the amphipathic compounds of Formula IV comprises a phosphate group bonded to the ring structure and a moiety Z as defined in Formula V. In the moieties of Formula V, V is H, or N 3 , or V and W together form a covalent bond, with H and N 3 being preferred. W is H or F, with H being preferred.
[0059] In the compounds of Formula IV, B is a purinyl moiety of Formula VI or a pyrimidinyl moiety of Formula VII, each of which are substituted as described above. As used herein, a purinyl moiety comprises six- and five-membered aromatic rings having the molecular structure illustrated in Formula VI. Those skilled in this art will appreciate that the double bonds illustrated in Formula VI are present to represent that the purinyl moieties have aromatic character, and that these double bonds may shift their positions in certain compounds due to the presence of certain substituents to retain the aromatic character of the moiety; in particular, those moieties having ═O or NH 2 substituents at positions 2 and 4, such as adenine, guanine, xanthine, and hypoxanthine, are generally illustrated as having double bonds shifted from the positions shown in Formula VI. Similarly, as used herein a pyrimidinyl moiety comprises a six-membered aromatic ring having the molecular structure illustrated in Formula VII. Those skilled in this art will appreciate that the double bonds illustrated in Formula VII are included therein to represent that the moieties of Formula VII have aromatic character, and that these double bonds may shift for certain substituents, in particular for ═O and NH 2 at positions 2 and 4, in order for the moiety to retain its aromatic character. Preferably, B is selected from the group consisting of adenine, thymine, cytosine, guanine, hypoxanthine, uracil, 5-fluorouracil, 2-fluoro-adenine, 2-chloro-adenine, 2-bromo-adenine, and 2-amino-adenine.
[0060] Preferably, Z is selected from the group consisting of 3′-azido3′-deoxythymidine, dideoxyinosine, dideoxycytidine, and 2′, 3′-didehydro-3′-deoxythymidine.
[0061] In the compounds of Formula IV, m can be 1, 2, or 3, and n can be 0, 1, or 2. Preferably, the ring structure is a five- or six-membered ring; thus m is 2 or 3 when n is 0, m is 1 or 2 when n is 1, and m is 1 when n is 2. The ring structure provides conformational rigidity to the compound.
[0062] An exemplary compound of Formula IV is 3′-azido-3′-deoxy-5′-(3-hexadecylthiocyclohexyl)-phosphothymidine.
[0063] Experimentation has demonstrated the efficacy of the compounds of Formulas I, II, III and IV in combating viral infection. For example, compounds CP-128, CP-129, CP-130, CP-131, and INK-1 in nanomolar concentration substantially inhibit the HIV-1 activity in CEM-SS cells. Further, these compounds did so at noncytotoxic levels, thus indicating their promise as therapeutic agents for treatment of viral infections. The compounds of Formulas I, II, III and IV are believed to attach to the cell membrane and thus are particularly effective against infections caused by membrane-containing or envelope-containing viruses, as these viruses typically require access to the cell membrane to multiply and assemble through the manufacture of new viral particles. For example, the compounds of Formulas I, II, III and IV can inhibit the transport and/or incorporation of HIV-1 major glycoprotein gp120 in the cell membrane of an infected cell prior to viral assembly. Such inhibition can block the transmission of infectious HIV-1 into neighboring cells. In addition, compounds of Formulas I, II, III and IV can inhibit the production of the HBV core and “e” antigens, each of which contribute to the assembly of new virus particles and the spread of HBV infection. Other infections for which the compounds of Formulas I, II, III and IV should be efficious include those caused by other membrane-containing or envelope-containing herpesviruses, influenza, respiratory syncytial virus, mumps, measles, and parainfluenza viruses.
[0064] Experimentation has also shown that the compounds of Formulae I, II, III, and IV have potent anti-tumor activity. In particular, some of these compounds have IC 50 values of approximately 1.2 μM against the KB-cell line.
[0065] In the manufacture of a medicament according to the invention, hereinafter referred to as a “formulation,” the compounds of Formulas I, II, III and IV are typically admixed with, among other things, an acceptable carrier. The carrier must, of course, be acceptable in the sense of being compatible with any other ingredients in the formulation and must not be deleterious to the patient. The carrier may be a solid or a liquid, or both, and is preferably formulated with the compound as a unit-dose formulation, for example, a tablet, which may contain from 0.5 percent to 95 percent by weight of the active compound. One or more active compounds may be incorporated in the formulations of the invention, which may be prepared by any of the well known techniques of pharmacy consisting essentially of admixing the components.
[0066] The formulations of the invention include those suitable for oral, rectal, topical, intrathecal, buccal (e.g., sub-lingual), parenteral (e.g., subcutaneous, intramuscular, intradermal, or intravenous) and transdermal administration, although the most suitable route in any given case will depend on the nature and severity of the condition being treated and on the nature of the particular active compound which is being used.
[0067] Formulations suitable for oral administration may be presented in discrete units, such as capsules, cachets, lozenges, or tablets, each containing a predetermined amount of the active compound; as a powder or granules; as a solution or a suspension in an aqueous or nonaqueous liquid; or as an oil-in-water or water-in-oil emulsion. Such formulations may be prepared by any suitable method of pharmacy which includes the step of bringing into association the active compound and a suitable carrier (which may contain one or more accessory ingredients as noted above).
[0068] Suitable solid diluents or carriers for the solid oral pharmaceutical dosage unit forms are selected from the group consisting of lipids, carbohydrates, proteins and mineral solids, for example, starch, sucrose, lactose, kaolin, dicalcium phosphate, gelatin, acacia, corn syrup, corn starch, talc and the like.
[0069] Capsules, both hard and soft, are filled with compositions of these active ingredients in combination with suitable diluents and excipients, for example, edible oils, talc, calcium carbonate and the like, and also calcium stearate.
[0070] In general, the formulations of the invention are prepared by uniformly and intimately admixing the active compound with a liquid or finely divided solid carrier, or both, and then, if necessary, shaping the resulting mixture. For example, a tablet may be prepared by compressing or molding a powder or granules containing the active compound, optionally with one or more accessory ingredients. Compressed tablets may be prepared by compressing, in a suitable machine, the compound in a free-flowing form, such as a powder or granules optionally mixed with a binder, lubricant, inert diluent, and/or surface active/dispersing agent(s). Molded tablets may be made by molding, in a suitable machine, the powdered compound moistened with an inert liquid binder.
[0071] Liquid preparations for oral administration are prepared in water or aqueous vehicles which advantageously contain suspending agents, for example, methylcellulose, acacia, polyvinylpyrrolidone, polyvinyl alcohol and the like.
[0072] Formulations suitable for buccal (sub-lingual) administration include lozenges comprising the active compound in a flavored base, usually sucrose and acacia or tragacanth; and pastilles comprising the compound in an inert base such as gelatin, glycerin, sucrose, or acacia.
[0073] Formulations of the present invention suitable for parenteral administration conveniently comprise sterile aqueous preparations of the active compound, which preparations are preferably isotonic with the blood of the intended recipient. These preparations are preferably administered intravenously, although administration may also be effected by means of subcutaneous, intramuscular, intrathecal, or intradermal injection. The formulation should be sufficiently fluid that for easy parental administration. Such preparations may conveniently be prepared by admixing the compound with water or a glycine buffer and rendering the resulting solution sterile and isotonic with the blood. Such preparations should be stable under the conditions of manufacture and storage, and ordinarily contain in addition to the basic solvent or suspending liquid, preservatives in the nature of bacteriostatic and fungistatic agents, for example, parabens, chlorobutanol, benzyl alcohol, phenol, thimerosal, and the like. In many cases, it is preferable to include osmotically active agents, for example, sugars or sodium chloride in isotonic concentrations. Injectable formulations according to the invention generally contain from 0.1 to 5 percent w/v of active compound and are administered at a rate of 0.1 ml/min/kg.
[0074] Formulations suitable for rectal administration are preferably presented as unit dose suppositories. These may be prepared by admixing the active compound with one or more conventional solid carriers, for example, cocoa butter, and then shaping the resulting mixture.
[0075] Formulations suitable for topical application to the skin preferably take the form of an ointment, cream, lotion, paste, gel, spray, aerosol, or oil. Carriers which may be used include vaseline, lanolin, polyethylene glycols, alcohols, and combinations of two or more thereof. The active compound is generally present at a concentration of from 0.1 to 15 percent w/w, for example, from 0.5 to 2 percent w/w.
[0076] Formulations suitable for transdermal administration may be presented as discrete patches adapted to remain in intimate contact with the epidermis of the recipient for a prolonged period of time. Such patches suitably contain the active compound as an optionally buffered aqueous solution of, for example, 0.1 to 0.2M concentration with respect to the said active compound.
[0077] Formulations suitable for transdermal administration may also be delivered by iontophoresis (see, for example, Pharmaceutical Research 3 (6), 318, (1986)) and typically take the form of an optionally buffered aqueous solution of the active compound. Suitable formulations comprise citrate or bis\tris buffer (pH 6) or ethanol/water and contain from 0.1 to 0.2M active ingredient.
[0078] The compounds of Formulas I, II, III and IV are administered in an amount sufficient to combat viral infection. The dose can vary depending on the compound selected for administration, the subject, the route of administration, and other factors. Preferably, the compound is administered in an amount of at least 0.1 ng/kg, 1 ng/kg, 0.001 μg/kg or more, and is adminstered in an amount no greater than 0.1 g/kg, 0.01 g/kg, 1 mg/kg, or less.
[0079] The invention is illustrated in greater detail in the following nonlimiting examples. In the Examples, “g” means grams, “mg” means milligrams, “μg” means micrograms, “μM” means micromolar, “mL” means milliliters, “° C.” means degrees Celsius, “THF” means tetrahydrofuran, “DMF” means dimethylformamide, “mol” means moles, “mmol” means millimoles, and “psi” means pounds per square inch.
EXAMPLE 1
Preparation of Amidoalkyl Derivatives
[0080] The procedure set forth below was used to prepare the following compounds:
[0081] (a) 1-dodecanamido-2-decyloxypropyl-3-phosphocholine (CP-128)
[0082] (b) 1-dodecanamido-2-octyloxypropyl-3-phosphocholine (CP-130)
[0083] (c) 1-dodecanamido-2-dodecyloxypropyl-3-phosphocholine (CP-131)
[0084] 3-Amino-1,2-propanediol was reacted with lauroyl chloride at room temperature in pyridine and dimethyl formamide. The resulting dodecanamido propanediol was recrystallized from chloroform, then reacted with triphenylmethyl chloride. The tritylated product was recrystallized from hexanes. The C-2 hydroxyl was alkylated by reaction with sodium hydride and the appropriate alkyl bromide in tetrahydrofuran for formation of the ether linkage at C-2 (1-bromodecane for CP-128; 1-bromooctane for CP-130; 1-bromododecane for CP-131). Column chromatography on silica gel with a discontinuous gradient of hexanes:ethyl acetate (95:5 to 80:20) produced the desired 1-dodecanamido-2-alkoxy-3-trityloxypropane. Detritylation with p-toluensulfonic acid in 5:1 methylene chloride:methanol gave product having a free primary hydroxyl after column chromatography (hexanes:ethyl acetate 95:5 to 0:100). Reaction with 2-bromoethyl phosphodichloridate in diethyl ether and pyridine produced the phosphate ester, which was purified on silica gel with chloroform:methanol (100:0 to 2:1). Displacement of the bromide with aqueous trimethylamine in chloroform:isopropanol:dimethyl formamide (3:5:5) gave the final phosphocholine product after column chromatography with chloroform:methanol:ammonium hydroxide (70:35:1 to 70:35:7).
EXAMPLE 2
Preparation of 1-dodecyloxy-2-decyloxypropyl-3-phosphocholine (CP-129)
[0085] Isopropylidene glycerol was alkylated using potassium hydroxide and 1-bromododecane in toluene. The resulting ketal was hydrolyzed with hydrochloric acid in methanol, and the diol formed thereby was recrystallized from methanol. The remaining reaction steps (tritylation, alkylation, detritylation, phosphorylation, amination) followed the procedures described above in Example 1 for the alkylamido derivatives.
EXAMPLE 3
Preparation of cis- and trans-3-hexadecylthiocyclohexylphosphocholine (INK-1)
[0086] 2-Cyclohexenone (0.14 mol, 13.4 mL) was dissolved in 10 mL of 10 percent sodium hydroxide and 50 mL of THF. An equimolar amount of hexadecyl mercaptan (0.14 mol, 42.9 mL) was added to the unsaturated ketone and the mixture refluxed to produce 3-hexadecylthiocyclohexanone (70 percent yield). This product (5.23 mmol, 1.851 g) was dissolved in methanol and reduced with sodium borohydride (5.23 mmol, 0.199 g) to give a racemic mixture of 3-hexadecylthiocyclohexanol (yield 62 percent; cis:trans ratio 4:1). The phosphorylating agent was prepared by refluxing phosphorus oxychloride (0.65 mol, 60.8 mL) and 2-bromoethanol (0.38 mol, 27.0 mL) in 25 mL of trichloroethylene to produce 2-bromoethyl dichlorophosphate (yield 53 percent). The 3-hexadecylthiocyclohexanol (0.56 mmol, 0.200 g) was dissolved in diethyl ether:THF (2:1) and refluxed with the 2-bromoethyl dichlorophosphate (222 mmol, 0.3 mL) to produce 3-hexadecylthiocyclohexyl phosphoethyl bromide (yield 54 percent). The latter (0.276 mmol, 0.150 g) was dissolved in isopropyl alcohol chloroform:DMF (5:3:5) and heated at 65° C. with trimethylamine (0.042 mol, 2 mL) to produce the desired product, 3-hexadecylthiocyclohexyl-phosphocholine (yield 38 percent).
[0087] This procedure can also be used to prepare 3-alkylthio-cyclopentyl derivatives by substituting 2-cyclopentenone.
EXAMPLE 4
Preparation of cis- and trans-3-hexadecanamido-cyclohexylphosphocholine
[0088] 2-Cyclohexenone is reacted with benzylamine to give 3-benzylaminocyclohexanone. Hydrogenolysis of the benzylamino group then gives 3-aminocyclohexanone. Reaction with hexadecanoyl chloride affords 3-hexadecanamidocyclohexanone, which is then reduced with sodium borohydride to produce a cis/trans mixture of 3-hexadecanamidocyclohexanol. Separation by column chromatography then gives the pure isomers. Reaction with bromoethylphosphodichloridate, then with trimethylamine will produce 3-hexadecanamido-cyclohexylphosphocholine.
[0089] Synthesis of the 2- and 4-alkylamido derivatives can be carried out following essentially similar procedures with the substitution of appropriate starting materials.
EXAMPLE 5
Preparation of 3′-azido-3′-deoxy-5′-(dodecanamido-2-decoxypropyl)-phosphothymidine
[0090] 3-Dodecanamido-2-decoxy-propanol was synthesized via the scheme described in Morris-Natschke et al., C.I. Med. Chem. 29:2114 (1986). This alcohol was phosphorylated with diphenyl chlorophosphate in pyridine to give the corresponding phospate ester. The phenyl groups were then removed via hydrogenolysis with PtO 2 . The phosphatidic acid derivatives were then conjugated to the 5′-hydroxyl of AZT (DCC condensation).
EXAMPLE 6
Preparation of 3′-azido-3′-deoxy-5′-(dodecyoxy-2-decyloxypropyl)-phosphothymidine
[0091] A. 3-Dodecyloxy-1,2-propanediol
[0092] Isopropylideneglycerol (solketal, 26.4 g, 0.20 mol) in 60 mL of tolune was added dropwise to a solution of powdered KOH (22.4 g., 0.04 mol) in 150 mL toluene. The resulting mixture was refluxed for 4 hours. 1-Bromododecane (50 g, 0.20 mol) in 40 mL of tolune was then added dropwise, and the solution was refluxed for 10 hours. After cooling, the reaction mixture was diluted with 200 mL of ice-water and extracted with diethyl ether (3×100 mL). The ether layers were dried over magnesium sulfate, and the solvent was removed in vacuo. The residue was dissolved in 60 mL of diethyl ether and 260 mL of MeOH. Concentrated HCl (60 mL) was added, and the solution was refluxed for 16 hours. After cooling, ice-water (150 mL) was added, and the layers were separated. The aqueous layer was extracted with diethyl ether (2×75 mL). The combined organic fractions were then dried over sodium sulfate, filtered, and concentrated in vacuo. The solid residue was recrystallized from MeOH to give 37 g (0.14 mol, 71%) of a white solid.
[0093] B. 3-Dodecyloxy-1-triphenylmethoxy-2-propanol
[0094] The diol synthesized in Section A was tritylated with trityl chloride (59 g, 0.21 mol) in pyridine (200 mL) at 70° C. for 5 hours and then at room temperature overnight. The pyridine was removed under vacuum, and the solid residue was partitioned between water and CHCl 3 . The CHCl 3 layer was washed with 5 percent HCl and water, then dried over magnesium sulfate. After removal of solvent, the product was recrystallized from hexanes:ethyl acetate (10:1) to give 19 g of pure product.
[0095] C. 3-Dodecyloxy-2-decyloxy-1-triphenylmethoxypropane
[0096] The trityl ether of Section B (13.5 g, 0.027 mol) was added dropwise to an ice-cooled suspension of sodium hydride (80%, 1.6 g, 0.054 mol) in 150 mL of tetrahydrofuran under nitrogen. After stirring for 2 hours at room temperature, heat was applied (55° C.). 1-Bromodecane (6 g, 0.027 mol) was added dropwise; heating was continued for 6 hours. After cooling for 3 hours, water was added slowly. Diethyl ether (2×100 mL) was added, and the solution washed with 15 percent sodium thiosulfite, water, and brine. After drying over sodium sulfate, the ether was removed, and the residue was chromatographed with a gradient of hexanes:ethyl acetate (100:0 to 20:1) to give 9 g (52%) of a clear liquid.
[0097] D. 3-Dodecyloxy-2-decyloxy-1-propanol
[0098] Detritylation of the product of Section C was accomplished using p-toluenesulfonic acid (0.9 g) in CHCl 3 :MeOH (72 mL:36 mL) (stirred at room temperature for 48 hours, added 10 percent sodium bicarbonate, extracted with CHCl 3 , dried over magnesium sulfate, and concentrated). The residue was purified by column chromatography using a gradient of hexanes:ethyl acetate (20:1 to 5:1) to give 3.5 g (63%) of pure 3-dodecyloxy-2-decyloxy-1-propanol.
[0099] E. 3-Dodecyloxy-2-decyloxypropyl Diphenyl Phosphate
[0100] Diphenylchlorophosphate (0.7 mL, 3.4 mmol) in 10 mL of diethyl ether was cooled to 4° C. under nitrogen. 3-Dodecyloxy-2-decyloxy-1-propanol (1.0 g, 2.6 mmol) in 15 mL of pyridine and 5 mL of diethyl ether was added. The solution was warmed to room temperature then heated to about 52° C. for 3 hours. It was then cooled to room temperature, diluted with 50 mL of diethyl ether, and washed with water (2×25 mL), 0.5 N HCl (25 mL), and then water (25 mL). The organic layer was dried over sodium sulfate, filtered, and concentrated in vacuo to an oil. Chromatography with a gradient of hexanes:ethyl acetate (10:1 to 1:1) produced 980 mg (1.5 mmol, 60%) of pure product.
[0101] F. 3-Dodecyloxy-2-decyloxpropyl Phosphate
[0102] PtO 2 (69 mg) was placed in a Parr hydrogenation bottle. The diphenyl phosphate of Section E (500 mg) in 100 mL of EtOH was then added. The reaction mixture was hydrogenated at 15 psi for 1.5 hours until hydrogen uptake ceased. The reaction mixture was then filtered through Celite, and the EtOH was removed in vacuo. The oil was dissolved in 25 mL of pyridine, concentrated in vacuo, and dried under high vacuum to give 350 mg of pure solid phosphatidic acid.
[0103] G. 3′-Azido-3′-deoxy-5′-(3-dodecyloxy-2-decyloxypropyl)-phosphothymidine
[0104] AZT (43 mg, 0.16 mmol) and the phosphatidic acid of Section F (105 mg, 0.22 mmol) were azeotropically dried with pyridine (3×3 mL) by in vacuo removal. Dicyclohexylcarbodiimide (220 mg, 1.07 mmol) was added, and the drying was repeated 4 times. A final 3 mL portion of pyridine was added, and the reaction mixture was stirred at room temperature in a desiccator for 4 days. Water (1 g) was added, and the mixture was stirred for 4 hours. The solvents were removed in vacuo, and the crude material was chromatographed on 2 g of silica gel using a gradient of CHCl 3 :MeOH (15:1 to 2:1). The product was dissolved in 11 mL of CHCl 3 :MeOH:H 2 O (4:6:1) and stirred with 1.5 g of Whatman preswollen microgranular cation (Na + ) exchange concentrated in vacuo to give 37 mg of product (22%). FAB ms showed a [MH+Na] ion at 752.4350 (C 35 H 64 N 5 O 9 PNa, 1.4 ppm) and a [M+2Na] + ion at 774.4179 (C 35 H 63 N 5 O 9 PNa 2 , 2.0 ppm).
EXAMPLE 7
Procedure for Assessing Anti-HIV-1 Activity
[0105] The inhibitory effects of synthetic phospholipid compounds on the replication of human immunodeficiency virus type 1 (HIV-1) virus in cells was examined by the plaque assay procedure of L. Kucera et al., Aids Research and Human Retroviruses 6, 491 (1990). In brief, CEM-SS cell monolayers were infected with HIV-1. Infected cells were overlaid with RPMI-1640 medium plus 10 percent fetal bovine serum (FBS) supplemented with different concentrations of inhibitor. Plaques were counted at five days after infection. In this assay HIV-1 syncytial plaques are seen as large, multicellular foci (10 to 25 nuclei/syncytium) that appear either brown and granular or clear. Since the number of HIV-1 syncytial plaques correlates with reverse transcriptase (RT) and p24 core antigen activity in the HIV-1 infected cell overlay fluids, the syncytial plaque assay can be used to quantify the amount of infectious virus. Reverse transcriptase activity was assayed according to a described procedure (B. J. Poeisz et al., Proc. Natl. Acad. Scie. (U.S.A.) 77, 7415 (1980)). The activity of p24 core antigen induced by HIV-1 infection of CEM-SS cells was measured spectrophotometrically using the commercial Coulter EIA.
EXAMPLE 8
Results of Assessment of Anti-HIV-1 Activity
[0106] The results (Table 1) showed that all of the lipid compounds tested have an IC 50 against HIV-1 syncytial plaque formation ranging from 0.11 to 0.64 μM. The compounds' IC 50 for cell cytotoxicity ranged from 11.85 to 75.7 μM. The highest differential selectivity (611.7), which is a ratio of the cytotoxicity to the anti-HIV-1 activity, was obtained with compound CP-130.
TABLE 1 Evaluation of Ether Lipids for Cytotoxicity and Anti-Viral Activity in CEM-SS Cells IC50 (μM) Differential Compounds Cytotoxicity Anti-HIV-1 Activity Selectivity CP-128 31.6 0.14 225.7 CP-129 75.7 0.64 176.0 CP-130 67.2 0.11 611.7 CP-131 36.6 0.32 114.2 JM-1 (cis) 11.85 0.42 28.2
[0107] Cytotoxicity was measured by uptake of TdR-H 3 into total DNA in the presence of serial concentrations of compound.
[0108] Anti-HIV-1 activity was measured by standard plaque assay using CEM-SS cell monolayers.
[0109] Differential selectivity was determined by dividing the IC50 for cytotoxicity by the IC50 for anti-HIV-1 activity.
EXAMPLE 9
Assessment of HBV Activity Inhibition
[0110] Human hepatoblastomas (HepG2) cells were tranfected with plasmid DNA containing tandem copies of HBV genomes. These cells constituitively replicate HBV particles. HepG2 cells were treated with varying concentrations of CP-128 to determine the toxic cell concentration (TC 50 ) by neutral red dye uptake. Also, the inhibitory concentration (IC 50 ) of CP-128 for HBV replication was determined by ELISA.
[0111] It was determined that CP-128 cytotoxicity (TC 50 ) was 61.7 μM and the anti-HIV-1 activity (IC 50 ) was 15.6 μM (Table 1). These data indicate that CP-128 has selective anti-HBV activity. Mechanism studies indicate that CP-128 can have an inhibitory effect on the cellular production of HBV-induced DNA, core antigen (HBcAg) and “e” antigen (HBeAg). As a result, it is postulated that CP-128 and other compounds of the present invention are likely inhibiting the assembly of HBV nucleocapids and the packaging of viral pregenomic DNA.
[0112] The foregoing examples are illustrative of the present invention and are not to be construed as limiting thereof. The invention is defined by the following claims, with equivalents of the claims to be included therein. | A method of treating viral infections, and in particular HIV-1, hepatitis B virus, and herpes virus, is disclosed. The method comprises administering to a subject in need of such treatment an infection-controlling amount of a phospholipid or phospholipid derivative. | 2 |
This invention relates to methods of assembly of offshore tower structures.
BACKGROUND OF THE INVENTION
More particularly, the invention is concerned with an offshore tower structure of the kind comprising a central column to extend upwardly in use from the sea bed to support a platform and carry services such as conductors and risers between the sea bed and the platform, and a structure to support the column, the support structure including at least three legs joined at their apex by a sleeve which in use surrounds and supports the column above the sea bed. Such a structure is herein referred to as an "offshore tower structure of the kind defined."
An example of an offshore tower structure of the kind defined is seen in our British Pat. No. 2136860. In this example, the support structure has both upper and lower sleeves for slidably receiving the column. Assembly of this structure is by sliding one end of the column through both the sleeves and fixing, for example, by introducing grout between the column and sleeves.
Another example of an offshore tower structure of the kind defined is seen in our British Pat. No. 2116237. In this example, the support structure includes bracing to provide additional strength and foundations for the column and legs can be pre-installed on the sea bed.
The present invention offers an alternative assembly technique which is suitable, for example, for occasions where the central column is too large to be lifted by an available crane vessel.
BRIEF SUMMARY OF THE INVENTION
The invention provides a method of assembly of an offshore tower structure of the kind defined in which the column is engaged with the sleeve of the support structure by positioning the column so that its longitudinal axis is vertical or nearly vertical, positioning the support structure so that the sleeve is uppermost and the axis of the sleeve is vertical or nearly vertical, with the sleeve above the top of the column, and positioning the column in the sleeve by relative movement of the column and support structure.
By way of example, various embodiments of the invention will now be described with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1A to 1E illustrate one form of offshore tower structure in various stages of construction and using various assembly methods, and
FIGS. 2 to 5 illustrate alternative constructions and assembly methods.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
There is seen in FIGS. 1A to 1E a central column 10 and an integral pre-formed support structure 11. The support structure 11 here comprises three support legs 13 which are joined at their apex by a column-receiving sleeve 14. The lower ends of the legs 13 are connected by a structure 12 which serves as a foundation when thestructure is on the sea bed. The foundation structure 12 includes a lower column receiving sleeve 15. It will be seen that the support structure 11 is of pyramind shape, and it will be understood that the structure may comprise more than three legs. The column 10 and support structure 11 can be ballasted and de-ballasted by flooding/draining water from the legs and column, which are hollow tubular members. The water ballast in the column and legs is illustrated by the shaded areas in the drawings. The level of the water above the sea bed is illustrated pictorially in the drawings by surface ripples 16, and the sea bed is illustrated pictorially by a shadow 17.
In the method of assembly illustrated in FIG. 1A, the column 10 is floating and positioned with its longitudinal axis vertical. The support structure 11 is also floating, but is positioned at a slightly inclined angle to the vertical. This allows room for the first assembly step, as described below. The support structure 11 is held in position by means of lines 18, which may be anchor lines or lines to vessels such as tug boats. A fender (not seen in FIG. 1A) is interposed between the column 10 and the upper sleeve 14 to prevent collision damage. The first assembly step is to position the bottom of the column 10 directly over the lower sleeve 15, as seen in FIG. 1A. The column 10 is then engaged with the lower sleeve 15, as seen in FIG. 1B, by relative longitudinal movement between the column and sleeve. This may be done by ballasting the column 10 or deballasting the support structure 11 or by a combination of both. It will be appreciated here that the lower sleeve 15 has sufficient clearance to allow for the fact that the column is out of alignment relative to the axis of the sleeve, as can be seen in FIG. 1A. With the column now in engagement with the lower sleeve 15, the column is then brought into alignment with the upper sleeve, as seen in FIG. 1B. The column 10 is then engaged with the upper sleeve 14 by relative longitudinal movement between the column and sleeve. This may again be done by suitable ballasting/deballasting of the column and/or support structure. Alternatively or additionally, a pulling force may be used for engagement of the column with the sleeves, e.g. from a vessel such as a crane vessel, or from a specially installed winch deck on the top of the support structure. Such a pulling force is illustrated by reference 20 in FIG. 1B. After thus assembling the column and support structure together, the two are rigidly fixed together, e.g. by filling the spaces between the column and sleeves with grout. This can be done with the assembled structure still in its vertical position or in a horizontal position, after deballasting. The assembled structure is then lowerable into position on the sea bed where it can be anchored by driving piles through pile sleeves 19 provided in the foundation structure 12.
It will be understood that it is not essential though it may be desirable, for either the column or the support structure to be exactly vertical during assembly.
FIG. 1C shows use being made of an assisting vessel 21, with suitable fenders 22, and a winch 23.
The winch is used here to control line 24, which is attached to the base of the column 10, to aid engagement of the base of the column with the lower sleeve 15.
FIG. 1D shows lifting of the central column 10 using the crane boom 25 of a crane vessel 26 after engagement of the column with the lower sleeve 15. The vessel 26 is anchored by lines 27 and holds the support structure 11 in position by line 28. 29 represents a fender.
FIG. 1E shows an alternative assembly method. Again, the column 10 is positioned with its longitudinal axis vertical and the support structure 11 slightly offset from the vertical. Here, the column 10 is first engaged with the upper sleeve 14 of the support structure 11. This is done by positioning the support structure 11 with the upper sleeve 14 immediately above the top of the column 10 and moving the column and sleeve longitudinally relative to each other. This can be achieved by using the crane vessel 26 seen in FIG. 1E to lift the column 10. Additionally or alternatively, the column 10 and/or support structure 11 may be suitably ballasted/deballasted. Horizonal position control for the upper end of the column may be provided by a tug 30 or tugs and tugger lines 31 or by anchor lines. It will be appreciated here that it is the upper sleeve 14 which must have sufficient clearance to allow for the fact that the column is out of alignment with the axis of the sleeve upon engagement, as can be seen clearly in FIG. 1E. The lower end of the column 10 can be left to find its own horizontal position by gravity for engagement of the column with the lower sleeve 15.
In FIG. 2 there is seen a modified version of the support structure shown in FIG. 1A. In the support structure 11' shown in FIG. 2, the lower location for the column 10 is provided in the form of an openable and closable collar 35. The collar 35 is in two parts which are connected together by a hinge 36 and which have flanges 37 to receive clamping bolts. The column here is engaged with the lower location by simple relative lateral movement between the column and the open collar. The collar can then be closed and bolted.
In FIG. 3 there is seen a further modified version of the support structure shown in FIG. 1A. In the support structure 11" shown in FIG. 3, the foundation structure is in two parts 12a and 12b. The upper part 12b is pre-formed integrally with the support legs 13 and upper sleeve 14, whereas the lower part 12a is separate and incorporates the lower sleeve 15. The lower part 12a here can be pre-installed in position on the sea bed whilst the column 10 and upper part 12a of the support structure are assembled. Positioning/guiding lines 40 are conveniently used for assembling together the two parts of the foundation structure during installation, as can be seen in FIG. 3.
FIG. 4 is similar to FIG. 3 and shows the case where individual foundation units 12X and 12Z may be provided for the legs and column and pre-installed on the sea bed.
In FIG. 5 there is seen a somewhat different construction. Here again three support legs 13 are formed into a support structure 11 for the column 10 with an upper sleeve 14 at their apex for slidingly receiving the column. In addition, however, between the legs 13 and between the column 10 and legs there is provided a bracing structure 41 comprising an arrangement of stiffening struts. As can be seen in FIG. 5, a lower sleeve 15 is provided for the column at the bottom of the bracing structure 41 and a collar 42 is provided at the top of the bracing structure. The collar 42 is similar to that seen in FIG. 2, being openable and closable with hinged parts and flanges for clamping bolts. The structure is seen in FIG. 5 at an intermediate stage of construction with the lower end of the column 10 having been located in the lower sleeve 15 and engaged with the collar 42. The column 10 is about to be engaged with the upper sleeve 14. This may be effected by pulling with line and winch in the direction of arrow 43, as seen in FIG. 5. For this purpose, a temporary winch deck 44 may be incorporated onto the top of the upper sleeve 14 of the support structure 11. The deck 44 may also be used to position the mooring winches. It will again be appreciated here that the sleeve into which the column is first engaged (i.e. upper sleeve 14 or lower sleeve 15) will have sufficient clearance to allow for the offset of the column. After the column and support structure have been assembled together, the entire assembly can then be lowered onto a foundation unit or units which has been pre-installed on the sea bed. | A method of assembly of an offshore tower comprises engaging a column with a sleeve of a support structure by positioning the column so that its longitudinal axis is vertical or nearly vertical, positioning the support structure so that the column-receiving sleeve is uppermost and the axis of the sleeve is vertical or nearly vertical, with the sleeve above the top of the column, and positioning the column in the sleeve by relative longitudinal movement between the column and support structure. | 4 |
FIELD OF THE INVENTION
[0001] The invention relates to cleaning apparatus; in particular to apparatus for cleaning tracheo-oesophageal valves.
BACKGROUND OF THE INVENTION
[0002] A laryngectomy is a surgical procedure which involves the removal of a patient's voice box and other surrounding structures often for treatment of cancer of the larynx.
[0003] Tracheo-oesophageal prosthetic valves are devices which allow vocal function to be restored to a patient following a laryngectomy. This type of valve is inserted into a hole between the trachea and the oesophagus. The valve blocks the flow of secretions and food materials from the oesophagus to the airway, but allows a passage of air from the airway into the throat to permit speech.
[0004] These valves usually stay in place for approximately 6 months before being replaced by a doctor or nurse or other specially trained therapist. The valves can easily become contaminated with secretions and yeasts from the mouth which can cause infections. This can stop the device working altogether, necessitating the replacement of the valve. To prevent this happening, the valves must be cleaned daily by the patient. If valves are not cleaned effectively then their life span is shortened. Frequent replacement of these indwelling valves is not only inconvenient for a patient but can cause trauma to the opening in which the device is placed. These valves are also expensive and frequent replacement causes unnecessary expense.
[0005] Cleaning products available currently include small brushes for insertion into the valve, and pipettes with which to flush liquid through the valve. The pipettes available on the market do not give a good seal against the valve and leakage occurs during use which is inconvenient to the user. Also, the pipettes cannot be used at the same time as using a brush.
[0006] US 2002/0056219 describes a device for cleaning the inside of a gun barrel. The cleaner comprises a brush attached to a hollow rod with a handle at the opposite end. The brush is mounted so it can freely rotate when the handle is held stationary. A squeeze bottle containing cleaning fluid at the handle end can be squeezed to allow cleaning fluid to run along the hollow rod and onto the brush.
[0007] Brushes and pipettes available for cleaning these valves do not give very effective cleaning. The device described in US 2002/0056219 would not be suitable for cleaning tracheo-oesophageal valves as using this type of device would require the user to manually manipulate and rotate the brush whilst squeezing the bottle to dispense fluid into the valve.
[0008] The present invention offers cleaning apparatus that mitigates the above-identified problems.
SUMMARY OF THE INVENTION
[0009] The invention provides tracheo-oesophageal valve cleaning apparatus as specified in Claim 1 .
[0010] Preferred aspects of the invention are specified in the claims dependent on Claim 1 .
[0011] The invention provides apparatus that offers more effective cleaning of indwelling tracheo-oesophageal valves. The apparatus of the invention provides a combined brush and fluid dispenser that dispenses an amount of fluid in a one action flush, the brush being rotated to clean the valve by the same action that forces fluid across the brush and into the valve. More effective cleaning leads to prolonged life of the valves.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] In the drawings, which illustrate preferred embodiments of the invention:
[0013] FIG. 1 shows a first embodiment of a cleaning apparatus in a ‘before use’ configuration;
[0014] FIG. 2 is an exploded view of the internal workings of the apparatus of FIG. 1 ;
[0015] FIG. 3 show the location of a tracheo-oesophageal valve;
[0016] FIG. 4 shows the cleaning apparatus of FIG. 1 after use;
[0017] FIG. 5 shows a second embodiment of a cleaning apparatus, with a cutaway portion showing the internal workings of the apparatus;
[0018] FIG. 6 shows an exploded cross-sectional view of the internal workings of the apparatus of FIG. 5 ;
[0019] FIG. 7 shows a further embodiment of a cleaning apparatus with a ring-type handle; and
[0020] FIG. 8 shows an embodiment of the cleaning element of the cleaning apparatus of FIGS. 1 and 5 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0021] With reference to FIG. 1 , a first embodiment of a cleaning apparatus 1 comprises a fluid dispenser 2 with a first narrow end 7 and a second broader end 8 . A rod 3 is present within the fluid dispenser 2 . The rod 3 is connected to a shaft 4 which extends beyond the fluid dispenser 2 and out through an outlet 6 . The shaft 4 is connected to a cleaning element, which in the example is a brush 5 .
[0022] The brush 5 may be detachable from the tip of the shaft 4 . The shaft 4 may also be removable from the end 19 of the rod 3 . Alternatively, both the brush 5 and shaft 4 may together be detachable from the end 19 of the rod 3 . The brush 5 and shaft 4 or the brush 5 may therefore be removed and replaced as necessary, without the need to replace the cleaning apparatus 1 .
[0023] The fluid dispenser 2 includes a cylindrical fluid reservoir 20 . A hollow plunger 17 fits into the cylinder 20 . A seal 9 between the plunger 17 and the cylinder 20 prevents fluid from leaking at broad end 8 of the fluid dispenser 2 . The plunger 17 mounts the seal 21 at one end thereof and a handle 10 at the other end. The rod 3 is located within plunger 17 . The end of the hollow plunger 17 mounting the handle 10 is sealed, whereas the end mounting the seal 9 includes an opening. The rod 3 is located within the plunger 17 .
[0024] The fluid reservoir 20 is filled with cleaning fluid for ejection from the outlet 6 . In a preferred embodiment the cleaning fluid is a saline solution or sodium bicarbonate. The reservoir 20 may be pre-filled with cleaning fluid, and the outlet 6 may be provided with a seal to prevent leakage of fluid before use of the apparatus 1 . Alternatively, the user may fill the reservoir 20 with cleaning fluid immediately prior to use.
[0025] As shown in FIG. 2 , the rod 3 is generally cylindrical in shape and has a substantially helical groove 13 extending along its outer surface.
[0026] The end 18 of the rod 3 is mounted within the plunger 17 such that it can freely rotate about its longitudinal axis. The other end 19 of the rod 3 sits in a housing formed in the dispenser 2 such that the rod 3 can freely rotate about its longitudinal axis but is constrained against movement in the direction X. The plunger 17 includes two protruding elements 15 and 16 each extending into groove 13 of the rod 3 .
[0027] In use, the user inserts the brush 5 into the tracheo-oesophageal valve 12 ( FIG. 3 ). A lip 14 of larger diameter than the brush 5 may be present. The lip 14 prevents the user inserting the dispenser 2 too far into valve 12 . Inserting a brush too far into the valve could damage the valve and a replacement may be required. The user grasps the device using the handles 11 and depresses the plunger 17 using the handle 10 , applying pressure in the direction labelled X in FIG. 1 . The movement of the rod 3 is constrained against movement in direction X as the end 19 of the rod 3 is in contact with the walls of the dispenser 2 . The protrusions 15 and 16 are forced to move along the helical groove 13 and the rod 3 is forced to rotate, thereby rotating the brush 5 inside the valve 12 . As the rod 3 rotates, the plunger 17 moves axially inside the dispenser 2 in the direction X. This axial movement of the plunger 17 forces fluid to flow out through the outlet 6 , over the brush 5 , and into the valve 12 . FIG. 4 shows the position of the plunger 17 after use.
[0028] The fluid dispenser 2 may be refilled with fluid after each use by placing the outlet 6 into an amount of fluid. Fluid is drawn up into the fluid reservoir 20 of the dispenser 2 by withdrawing the piston 17 to its original position (see FIG. 1 ). The rod 3 is constrained against movement in direction X as it is rotatably connected with the walls of the dispenser 2 . For example the walls of the dispenser 2 may comprise a groove in which sits one or more protrusions extending radially from the rod 3 . The protrusions 15 and 16 are forced to move back along the helical groove 13 . As the plunger 17 is withdrawn, the rod 3 is forced to rotate and the reservoir 20 is re-filled with fluid.
[0029] FIGS. 5 and 6 illustrate a second embodiment of the invention. Like reference numerals are used to refer to like features.
[0030] With reference to FIGS. 5 and 6 , a second embodiment of cleaning apparatus 25 comprises a fluid dispenser 26 with a first narrow end 27 and a second broader end 28 . A rod 31 is present within the fluid dispenser 26 . The rod 31 is connected to a shaft 4 which extends beyond the dispenser 26 and out through an outlet 29 . The shaft 4 is connected to a brush 5 . As in the previous embodiment, the brush 5 may be detachable from the cleaning apparatus 1 . The shaft 4 may also be removable. The brush 5 and shaft 4 together may be detachable from the cleaning apparatus 1 .
[0031] The fluid dispenser 26 includes a cylindrical fluid reservoir 30 . A hollow plunger 32 fits closely into the cylinder 30 . A circular seal 21 between the plunger 32 and the cylinder 30 seals the fluid reservoir 30 , minimising any leakage of fluid from the broad end 28 of the dispenser 26 . The plunger 32 mounts the seal 21 at one end thereof and a handle 10 at the other end. The rod 31 is located within the plunger 32 .
[0032] The fluid reservoir 30 is filled with cleaning fluid for ejection from outlet 29 . In a preferred embodiment the cleaning fluid is a saline solution or a sodium bicarbonate solution. As with the previous embodiment, the reservoir 30 may be pre-filled with cleaning fluid, and the outlet 29 may be provided with a seal to prevent leakage of fluid before use of the apparatus 25 . Alternatively, the user may fill the reservoir 30 with cleaning fluid immediately prior to use.
[0033] As shown in FIG. 6 , the internal hollow of plunger 32 is substantially cylindrical in shape and has a substantially helical groove 22 extending along its inner surface.
[0034] The end 33 of the rod 31 is mounted within the plunger 32 such that it can freely rotate about its longitudinal axis. The other end 34 of the rod 31 sits in a housing formed in the dispenser 26 such that the rod 31 can freely rotate about its longitudinal axis but is constrained against movement in the direction X. The rod 31 includes two protruding elements 23 and 24 each extending into the groove 22 on the internal surface of the hollow plunger 32 .
[0035] In use, the user inserts the brush 5 into their tracheo-oesophageal valve 12 ( FIG. 3 ). The narrow end 27 of the dispenser 26 is tapered. The tapered end 35 prevents the user inserting the dispenser 26 too far into valve 12 . The user grasps the device using the handles 11 and depresses the plunger 10 , applying pressure in the direction labelled X in FIG. 5 . The movement of the rod 31 is constrained against movement in direction X as it is rotatably connected with the walls of the dispenser 26 . In this embodiment the rod 31 comprises a circular groove in which sits one or more protrusions 36 and 37 extending radially from the dispenser 26 . Protrusions 36 and 37 are forced to move along this circular groove and hence movement of the rod 31 is constrained against movement in the direction X. As the plunger is depressed, the protrusions 23 and 24 are forced to move along the helical groove 22 and the rod 31 is forced to rotate, thereby rotating the brush 5 inside the valve 12 . As the rod 31 rotates, the plunger 32 moves axially inside the dispenser 26 in the direction X. This axial movement of the plunger 32 forces fluid to flow out through the outlet 29 , over the brush 5 , and into the valve 12 .
[0036] As with the previous embodiment, the fluid dispenser 26 may be refilled with fluid after each use by placing the outlet 29 into an amount of fluid. Fluid is drawn up into the fluid reservoir 30 of the dispenser 26 by withdrawing the plunger 32 to its original position. The rod 31 is constrained against movement in direction X as it is rotatably connected with the walls of the dispenser 26 . As fluid is drawn up, the protrusions 23 and 24 on the rod are forced to move back along helical groove 22 . As the plunger 32 is withdrawn, the rod 31 is forced to rotate and the reservoir 30 is re-filled with fluid. There may also be a lip at the broader end 28 of the dispenser 26 to prevent the plunger being unintentionally removed from the dispenser 26 when refilling the fluid reservoir 30 .
[0037] In a further embodiment of the invention, illustrated in FIG. 7 , the plunger 32 mounts a ring handle 38 . This feature enables a user to withdraw the plunger 32 using only one finger and means the device can be operated using only one hand.
[0038] In any of the aforementioned embodiments of the invention, the brush 5 may include bristles or other projections to aid cleaning of the valve. The brush 5 may include “fin-type” projections 39 such as those shown extending radially from the core 40 of the brush 5 in FIG. 8 . The projections 39 are easier to clean and harder wearing than bristles. They are made of rubber and are simple and inexpensive to manufacture.
[0039] The apparatus of the invention enables a user to efficiently clean a tracheo-oesophageal valve using a simultaneous fluid flush and rotating brush. This one step cleaning routine is much easier for a person to carry out and leads to more efficient cleaning, hence prolonging the life of the valve. | Tracheo-oesophageal valve cleaning apparatus comprises a fluid dispenser with a fluid reservoir and an outlet; a cleaning element mounted proximal to the outlet; and a drive mechanism including an element mounted axially within the said fluid dispenser, wherein axial movement of the element of the drive mechanism towards to the outlet causes both rotation of cleaning element and fluid to be dispensed from the outlet. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates generally to active sonar systems and more particularly to methods for optimizing noise-limited and reverberation-limited target detection in littoral regions.
2. Description of the Prior Art
A major problem for sonar systems operating in shallow water is reverberation from the ocean bottom. With expanding Navy operation in littoral regions, the shallow-water reverberation problem has received much recent attention from practitioners in the art. In 1995, Henry Cox et al. (Cox and Lai, “Geometric Comb Waveforms for Reverberation Suppression,” Proceedings, Twenty-Ninth Asilomar Conference on Signals, Systems, and Computers,” Pacific Grove, Calif., Oct. 29-Nov. 1, 1995, pp. 1185-1189) proposed a class of geometric comb waveforms that offer high range resolution and excellent Doppler properties for active sonar detection of moving targets in reverberation. Until the introduction of the geometric comb waveform, active sonar practitioners were limited to fighting reverberation by using one of two methods: a spectrally-flat wide-band pulse to spread reverberation noise power over the wide pulse band and minimize reverberation power in each range bin, or a long shaded (e.g., Hanning-weighted) continuous-wave (CW) pulse to concentrate reverberation noise power at the zero-Doppler bin and permit detection of non-zero Doppler targets. The flat wide-band pulse approach has limited effectiveness in multipath echo environments such as encountered in littoral regions and the CW shaped-pulse approach achieves Doppler reverberation rejection at the expense of range resolution. The uniform comb waveform is a variation of the wide-band pulse method that uses aplurality of equally-spaced spectral components (CW tone pulses) where the spacing is selected to be large with respect to the target Doppler shifts. Each spectral component provides an echo with properties similar to the wide-band pulse approach but coherent addition of a plurality N of such spectral components provides a processing gain of 10 log N over a single CW pulse. However, the uniform comb signal is disadvantaged by the large peak-to-average power ratio (large dynamic range) of the transmitted signal, which severely limits available average signal power levels needed in noise-limited environments, and by severe range ambiguity resulting from multiple equal amplitude peaks in the autocorrelation function.
The Cox geometric comb waveform solved the range ambiguity problem by using a plurality of non-uniformly-spaced spectral components (CW tone pulses) whose frequencies are spaced according to a geometric progression. While the geometric comb waveform has been welcomed with enthusiasm by active sonar practitioners because of excellent Doppler properties for suppressing reverberation with acceptable range ambiguity, the peak-to-average power problem, while improved by nearly 10 dB over the uniform comb signal, is still disadvantageous in noise-limited littoral regions. Cox et al. suggest easing the problem somewhat by clipping the spectral-component peaks to reduce the requisite transmitter dynamic range, but this introduces spectral distortion that can corrupt other processing gains.
T. Collins et al. (Collins and Atkins, “Doppler-Sensitive Active Sonar Pulse Designs for Reverberation Processing,” IEE Proc. - Radar, Sonar Navig., Vol. 145, No. 6, December 1998, pp.347-353) later compare the theoretical and experimental performance of several reverberation-insensitive active sonar waveforms. Collins et al. show that the linear period-modulated (LPM) chirp waveform is best for low Doppler targets at long ranges and the sinusoidally frequency-modulated (SFM) pulse waveform is preferred for suppressing reverberation effects, except that the Cox comb waveform eliminate much of the range-ambiguity of the SFM system.
Many littoral regions have negligible reverberation and detection capability is accordingly ambient-noise limited over some portion of the nominal detection range of an active sonar system. This may occur in slightly deeper water at close range or in shallow water at longer range. Because active sonar transmitters suitable for littoral operation are normally power- and duty-cycle-limited, there is a need for transmit waveforms with dynamic range limited to make use of as much available power as possible. Collins et al. suggest that the SFM waveform is preferred over the Cox comb waveform despite the resulting range-ambiguity problems because of the improved noise-limited performance of the higher average transmitter power available from SFM.
There is accordingly still a clearly-felt need in the art for an active sonar system that provides improved detection performance in either reverberation-limited or noise-limited littoral regions. These unresolved problems and deficiencies are clearly felt in the art and are solved by this invention in the manner described below.
SUMMARY OF THE INVENTION
This invention solves the active sonar comb-waveform power-limitation problem by introducing for the first time a system employing a new comb waveform herein denominated the triplet-pair comb waveform. Ambient noise-limited performance of the system of this invention is superior to that of systems employing other Doppler-sensitive waveforms such as the geometric comb waveform. Reverberation-limited performance of the system of this invention is slightly inferior to that of systems employing other Doppler-sensitive waveforms but this invention eliminates much of the range ambiguity problems seen with other non-comb waveforms.
It is a purpose of this invention to provide an active sonar system with improved noise-limited performance in littoral regions with reverberation.
In one aspect, the invention is an acoustic detection method comprising the steps of transmitting an acoustic signal employing a triplet-pair comb waveform to ensonify a target area, detecting acoustic reflections from the target area at a receiver transducer, generating a transducer output signal representing the acoustic reflections, and processing the transducer output signal to determine range and Doppler values for the target area.
In a preferred embodiment, the invention is an acoustic detection apparatus comprising an acoustic transmitter for transmitting an acoustic signal to ensonify a target area, wherein the acoustic signal includes a triplet-pair comb waveform, a receiver transducer for detecting acoustic reflections from the target area, a circuit for generating a transducer output signal representing the acoustic reflections, and a signal processor for processing the transducer output signal to determine range and Doppler values for the target area.
The foregoing, together with other objects, features and advantages of this invention, can be better appreciated with reference to the following specification, claims and the accompanying drawing.
BRIEF DESCRIPTION OF THE DRAWINGS
For a more complete understanding of this invention, reference is now made to the following detailed description of the embodiments as illustrated in the accompanying drawing, in which like reference designations represent like features throughout the several views and wherein:
FIGS. 1A-1D illustrate exemplary representations of comb waveform spectra from the prior art;
FIG. 2 shows a graphical representation of the cumulative frequency-deviation from uniformity over the spectral component (tine) sequence of several exemplary comb waveforms including an exemplary triplet-pair comb waveform of this invention;
FIG. 3 shows a graphical representation in the time domain of the individual triplet sub-waveforms making up the exemplary triplet-pair comb waveform of FIG. 2;
FIG. 4 shows a graphical representation in the time domain of the individual triplet-pair sub-waveforms making up the exemplary triplet-pair comb waveform of FIG. 2;
FIGS. 5A-5B show a graphical representation in the frequency domain of the twelve spectral components of the exemplary triplet-pair comb waveform of FIGS. 2-4 and a graphical representation of the associated autocorrelation function;
FIG. 6 shows a graphical representation in the time domain of the complete exemplary triplet-pair comb waveform of FIG. 2; and
FIGS. 7A-7B show graphical representations at two resolutions of the Q-function for several waveforms including the exemplary waveforms of FIG. 2 .
DESCRIPTION OF THE PREFERRED EMBODIMENT
The active sonar system of this invention is adapted for use in littoral regions at frequencies of 100-1000 Hz. In such waters, relative shallow depths can account for a drastic decrease in passive-Sonar target detection range and a concomitant drastic increase in active-sonar reverberation levels from sea-floor scattering, relative to deeper ocean regions.
Active target detection in many littoral environments is ambient-noise limited (negligible reverberation levels) over some part of the nominal detection range of an active sonar system. For these situations, power-efficient waveforms are important for maintaining or improving detection performance. Because sonar projectors operating in the 100-1000 Hz acoustic spectrum are usually power-limited, effective noise-limited operation requires the use of as much available transmitter power as possible. In these situations, waveform gain can be expressed as follows:
WG AN =PG+PF [Eqn. 1]
PG= 10*log( T*W ) [Eqn. 2]
PF= 20*log(η) [Eqn. 3]
where:
WG AN =waveform gain in ambient noise;
PG=processing gain;
PF=power factor;
T=waveform duration;
W=waveform bandwidth;
η=waveform efficiency, the ratio of the power radiated by the subject waveform to the power radiated by a uniformly-weighted single-frequency tone ping at the center of the waveform's frequency band.
Active target detection in other littoral environments is reverberation-limited (negligible ambient-noise levels) over some part of the nominal detection range of an active sonar system. This usually occurs for close to intermediate target ranges in shallow water. Reverberation is likely to be dominated by reflections from bottom-scatterers, which have intrinsic Doppler of zero. The observed Doppler is generally narrowly-distributed about zero Doppler, which is visualized as a “ridge” centered at zero Doppler on a range & Doppler vs. received energy contour diagram. The Q-function (see G. W. Deley, “Waveform Design,” Chapter 3 of Radar Handbook, M. I. Skolnik, editor, McGraw-Hill, New York, 1980), which is defined as the integral of the waveform ambiguity function taken along constant Doppler, illuminates the extent to which the zero-Doppler ridge may mask the target echo. The Q-function is known to express reverberation suppressability versus target Doppler.
Waveform power efficiency is not an issue in reverberation-limited operating regions because processed echo-to-reverberation ratios are nominally independent of the transmitter power level. But the system range-resolution determined the vertical offset of the Q-function and system Doppler resolution determines the slope of the Q-function in the zero-Doppler region. For any signal waveform, the Q-function amplitude is reduced by 10*log (W), where W is the effective signal bandwidth. For comb waveforms, W is proportional to the “filled” portion of the spectrum, which is generally much less than the spectral span of the comb component frequencies. The Q-function slope near zero-Doppler is steeper for comb waveforms of duration, T, relative to the (single-valued) comb spectral component duration, T C . So, for example, when T C =2*T/(M+1) for the M spectral components of a FHOP comb waveform, the Q-function slope is reduced drastically with respect to the same slope for a sinusoidal frequency-modulated (SFM) comb waveform (for which T C =T).
The ambiguity function (see, for example, A. W. Rihaczek, Principles of High - Resolution Radar, McGraw-Hill, New York, 1969) is a well-known tool for examining the range and Doppler resolution properties of active sonar waveforms. As is well-known (see, for example, C. E. Cook & M. Bernfeld, Radar Signals, an Introduction to Theory and Practice, Academic Press, New York, 1967), the ambiguity function is a three-dimensional representation of the point-target response of the sonar waveform as a function of range and Doppler. Resolution granularity is important for both range and Doppler. Good range resolution reduces signal-to-reverberation ratio (SRR) by reducing the effective size of the scatterers seen by the sonar receiver when processing returns for a particular beam/range/Doppler bin. To improve range resolution over that available from the CW-Hanning tone ping, comb waveforms generally, the spectral-component spacings in comb waveforms must be unequal. Good Doppler resolution improves signal-to-interference ratio (SIR) by rejecting interference energy at all Doppler values other than the target Doppler bin. During reverberation-limited operation, the detection of target echos at low Doppler values can be improved by using comb waveforms having the best Doppler resolution; that is, those where the comb spectral component duration, T C , is equal to the waveform transmission duration, T.
Table 1 presents a representative but incomplete list of useful active sonar system waveforms and identifies the qualitative standings of the respective Doppler resolution, range resolution and power efficiency characteristics. Table 1 is organized into Doppler-sensitive (comb waveform) and Doppler-insensitive categories. The Cox (geometric) comb waveform is important in the art because of its apparent high Doppler sensitivity at moderately good range resolution. The Cox comb waveform exhibits poor power efficiency, however. The Exponential Residue Codes waveform can be appreciated with reference to J. Alsup, “Exponential Residue Codes,” IEEE Transactions on Aerospace and Electronic Systems, November 1975, pp. 1389-90.
TABLE 1
Resolution
Power
Waveform
Range
Doppler
Efficiency
Doppler Insensitive
Linear Frequency Modulation (LFM)
high
low
high
Hyperbolic Frequency Modulation (HFM)
high
low
high
Rooftop (HFM or LFM)
high
low
high
Golay Complementary Pairs
high
low
high
Pseudo-Random Noise (PRN)
high
low
high
Exponential Residue Codes
high
low
high
Doppler Sensitive
Single-Frequency Pulse (CW)
low
high
medium
FHOP Comb
medium
low
high
Newhall Comb (LFM, HFM)
low
high
medium
Sinusoidal Frequency-Modulation (SFM)
low
high
medium
Cox Geometric Comb
medium
high
low
Triplet-Pair Comb of this invention
medium
high
medium
The Triplet-Pair (TP) comb waveform described herein below, for the first time offers improved power-efficiency in addition to the other advantages of the Cox geometric comb waveform. The TP comb overcomes the low power efficiency of the Cox comb while retaining most of its improved range resolution and excellent Doppler sensitivity.
FIGS. 1A-1D illustrate exemplary representations of comb waveform spectra for identical waveform parameters of 500 Hz center frequency (f C ), 10 second duration (T), 50 Hz bandwidth (W) and twelve in-band spectral components or “tines” (M).
In accordance with the method of this invention, the TP comb waveform of this invention is specified by the following steps:
Step (a) Choose the approximate number of comb spectral components (tines), M′, needed to provide a desired ambiguity-free Doppler regime, D′, in knots, such that:
M′= 1+( W/ (0.007* f C *D′ )) [Eqn. 4]
Step (b) Choose the actual number of comb tines, M, as a multiple of six to ensure an even number of triplet pairs, and compute the average tine separation, Δf, such that:
M= 6*round( M′/ 6) [Eqn. 5]
Δ f=W/ ( M− 1) [Eqn. 6]
Step (c) Arrange the tines into sets of triplets and spectrally-weight each triplet by the vector (−1 2 −1) for form an even number of weighted triplets.
Step (d) Arrange all weighted triplets into N pairs of weighted triplets and assign a frequency spacing Δf i , (i=1, . . . , N), between the tines within each triplet for the i th triplet-pair such that the internal tine spacing is uniform for the two triplets of the i th triplet-pair.
Step (e) Without disturbing the triplet internal tine spacing uniformity, assign different frequency spacings between frequency-adjacent triplets (that are not necessarily members of the same triplet pair) such that the overall TP comb tine frequency-spacing distribution approximate the tine frequency-spacing distribution of a geometric comb.
Step (f) Generate a vector of time-domain samples for each of the M spectral components (tines) and delay the time-domain phase of each vector for the tines in the second triplet of each triplet-pair by (0.5/Δf i ).
Step (g) Generate each of the N triplet-pair waveform elements by:
(1) summing the time-domain vectors for the six tines in the i th triplet-pair; and
(2) applying a Hanning window of length T H =2*T/(N+1)) to the resulting summation, where the Hanning window begins at a time delay of (i−1)*T H /2 for the i th triplet-pair.
Step (h) Form the final TP waveform by summing the N triplet-pair waveform elements.
FIG. 2 shows a graphical representation of the cumulative frequency-deviation from uniformity over the spectral component (tine) sequence of several exemplary comb waveforms. The waveform parameters used in this example are: f C =500 Hz, V=50 Hz, and D=13 knots. In FIG. 2, the line 10 shows the uniform frequency-spacing characteristic for a Uniform Comb waveform having twelve equally-spaced tines. The line 12 shows the geometric frequency-spacing characteristic of the Cox geometric comb having 12 tines spaced in accordance with the Cox method. For these exemplary parameters, the method of this invention defines a TP comb having twelve tines organized into two triplet-pairs. The line 14 shows the frequency-spacing characteristic for this exemplary embodiment of the TP comb waveform of this invention. The deviations from equal spacing are chosen to be the vector 0.1*[−2 −2 −1 −2 −2 0 2 2 1 2 2] Hz. This results in a spectral component vector [475.00 479.35 483.69 488.14 492.48 496.83 501.37 506.12 510.86 515.51 520.25 525.00] for this example. Note the uniform internal spacing within each triplets, which is an important feature of this invention. The inter-triplet spacings for TP comb 14 were chosen to “approximate” the spacing characteristic of the Cox comb 12 to retain the advantageous range and Doppler resolution of the Cox comb. The degree of approximation can be readily appreciated from FIG. 2 .
FIG. 3 shows a graphical representation of the individual triplet sub-waveforms (step (f) above) in the time domain, including the first triplet waveform 16 , the second triplet waveform 18 , the third triplet waveform 20 , and the fourth triplet waveform 22 . FIG. 4 shows a graphical representation of the two individual triplet-pair sub-waveforms 24 and 26 from the above example after Hanning-windowing in the time domain (step (g) above). The complete exemplary TP comb waveform in the time domain is shown in FIG. 6
FIG. 5A shows a graphical representation of the twelve spectral components of the exemplary TP comb waveform discussed above and FIG. 5B shows a graphical representation of the absolute value of the autocorrelation function of the same exemplary TP comb waveform, which can be shown to have a delay resolution of 2.1 seconds at −6 dB. This exemplary TP comb waveform can be shown to have a power factor of −4.8 dB, which improves the −9.7 dB power factor of the associated Cox comb waveform 12 (FIG. 2) by a factor of 300%.
Table 2 below shows the results of a noise-limited operating comparison made by the inventor of three Doppler-sensitive waveforms using the exemplary operating parameters described above. Note that the TP comb offers waveform gain in ambient-noise-limited environments superior to either the Cox comb or the CW-Hanning tone.
TABLE 2
Power Gain
Power Factor
Waveform Gain
Waveform
dB
dB
dB
Triplet-Pair Comb
2.6
−4.8
−2.2
Cox Geometric Comb
3.5
−9.7
−6.2
CW-Hanning Tone Ping
−2.3
−4.3
−6.6
FIGS. 7A-7B show graphical representations at two resolutions of the Q-function for five waveforms. The relative reverberation-limited performance of these five waveforms are compared using the above-described exemplary waveform parameters. The line 28 represents the HFM pulse (Table 1), the line 30 represents a uniform continuous-wave (CW) pulse, the line 32 represents the Hanning-shaded CW pulse (Table 1), the line 34 represents the Cox geometric comb (FIG. 2) and the line 36 represents the triplet-pair comb waveform of this invention. FIG. 7A shows reverberation-limited detection performance over the entire Doppler region of interest from zero to 20 knots Doppler. FIG. 7B shows reverberation-limited detection performance close to the zero-Doppler hump from zero to 1.5 knots Doppler. Table 3 characterizes this performance by determining at which Doppler a given Doppler-sensitive waveform provides reverberation-suppression (a) equal to or (b) 10 dB better than the HFM waveform designed for the same system with the same exemplary parameters described above.
TABLE 3
Suppression of Target Doppler below (knots)
Waveform
Equal to HFM
−10 dB of HFM
Cox Geometric Comb
.58
.76
CW-Hanning Tone Ping
.64
.80
CW Uniform Pulse
.90
1.16
Triplet-Pair Comb
1.24
4.01
From the above teachings, is may be readily appreciated that the Cox Geometric Comb and CW-Hanning waveforms offer slightly better reverberation-limited performance than does the triplet-pair comb waveform of this invention but the triplet-pair comb waveform offers noise-limited performance substantially better than do either of these other waveforms.
Clearly, other embodiments and modifications of this invention may occur readily to those of ordinary skill in the art in view of these teachings. Therefore, this invention is to be limited only by the following claims, which include all such embodiments and modifications when viewed in conjunction with the above specification and accompanying drawing. | An active sonar system with improved noise-limited performance in littoral regions with reverberation. This invention solves the active sonar comb-waveform power-limitation problem by introducing for the first time a system employing a new comb waveform herein denominated the triplet-pair comb waveform. Ambient noise-limited performance of the system of this invention is superior to that of systems employing other Doppler-sensitive waveforms such as the geometric comb waveform. Reverberation-limited performance of the system of this invention is slightly inferior to that of systems employing other Doppler-sensitive waveforms but this invention eliminates much of the range ambiguity problems seen with other non-comb waveforms. | 6 |
FIELD OF THE INVENTION
[0001] The invention is directed to diagnostic and therapeutic uses of gelsolin.
BACKGROUND OF THE INVENTION
[0002] Inflammation is the body's response to injury, infection, or molecules perceived by the immune system as foreign. Inflammation is characterized by pain, swelling and altered function of the affected tissue. Although the ability to mount an inflammatory response is essential for survival, the ability to control inflammation is also necessary for health. Inflammatory diseases are characterized by activation of the immune system in a tissue or an organ to abnormal levels that may lead to abnormal function and/or disease in the tissue or organ.
[0003] Inflammatory diseases are a major cause of morbidity and mortality throughout the world. They affect various organs and tissues such as blood vessels, heart, brain, nerves, joints, skin, the lung, eye, gastrointestinal tract, kidneys, thyroid, adrenals, the pancreas, liver, and muscle. Treatments of inflammatory diseases have drawn a great deal of attention from the pharmaceutical industry. A recurrent theme in discussions of treatment options for inflammatory disorders is the inadequacy of the standard of care. Management and treatments are seeing improvements but there are no cures. The most common approach to treating inflammatory disorders in the last decade has addressed the pro-inflammatory role of cytokines with compounds that bind to these molecules or their receptors.
[0004] Despite recent advances, current therapies for inflammatory diseases still entail alleviating symptoms and reducing inflammation with non-specific drugs, slowing disease progression with disease-modifying agents, and improving the quality of life with lifestyle modifications, all while contending with side effects and resistance to medications. Better treatment options with less potential for side effects are needed.
[0005] Because the outcome of treatment depends on a proper diagnosis, it is important to have proper tests to diagnose inflammatory diseases and to monitor the treatment of those diseases. A proper diagnosis permits a physician to institute proper and timely therapy. Proper monitoring of treatment allows the physician to decide on the course of treatment and to advise patients and their families about the expected disease course. Thus, there is also a strong incentive to identify new improved tests and approaches to diagnose and to evaluate treatments of inflammatory diseases.
[0006] Gelsolin, first discovered as an intracellular actin-binding protein involved in cell motility (Yin, H. L. & Stossel, T. P. (1979) Nature 281, 583-6), has been recently implicated in a number of diseases. While the true function of plasma gelsolin is not known, clinical and animal studies have shown that depletion of plasma gelsolin by injury and inflammation is associated with adverse outcomes. The proposed mechanism of gelsolin depletion is that it binds abundant actin in cells exposed by tissue breakdown. More recently, gelsolin was found to bind bioactive inflammatory mediators, lysophosphatidic acid, diadenosine phosphate, Aβ peptide (a peptide implicated in the pathogenesis of Alzheimer's disease), platelet-activating factor and possibly others.
SUMMARY OF THE INVENTION
[0007] Gelsolin (GSN), specifically cytoplasmic gelsolin (cGSN), in addition to being an intracellular actin-binding protein involved in cell motility, is also an abundant secretory protein (Yin, H. L., Kwiatkowski, D. J., Mole, J. E. & Cole, F. S. (1984) J Biol Chem 259, 5271-6). The exported isoform of gelsolin, designated plasma gelsolin (pGSN), has 25 additional amino acids and originates from alternative splicing of a single gene (Kwiatkowski, D. J., Stossel, T. P., Orkin, S. H., Mole, J. E., Cohen, H. It. & Yin, H. L. (1986) Nature 323, 455-8).
[0008] This invention is based on the surprising discovery that plasma gelsolin levels are reduced in blood samples from human subjects with an inflammatory disease, rheumatoid arthritis (RA). These findings support the hypothesis that reductions in plasma gelsolin levels reflect the primary injury inflicted on joint tissues by the causative agency of rheumatoid arthritis and precede joint pain and destruction by the resultant inflammatory process. These observations provide a basis for treatment with gelsolin to prevent and/or suppresses the manifestations of inflammatory diseases. One correlate of these observations is that monitoring of plasma gelsolin levels could become part of the management strategy of rheumatoid arthritis.
[0009] Without intending to be bound by any particular mechanism or theory, it is believed that gelsolin might be exerting its protective effect by inhibiting mediators of inflammation. Thus, the invention is directed to methods of using gelsolin to diagnose inflammatory diseases and to monitor the effect of therapy. The invention also involves the use of gelsolin to treat inflammation and inflammatory diseases.
[0010] According to one aspect of the invention, a method for characterizing a subject's risk profile of developing a future inflammatory disease (e.g., rheumatoid arthritis in some preferred embodiments) is provided. The method comprises obtaining a level of gelsolin in the subject and comparing the level of the gelsolin to a predetermined value. The subject's risk profile of developing an inflammatory disease (e.g., rheumatoid arthritis) is characterized based upon the level of gelsolin in comparison to the predetermined value. A level of gelsolin at or below the predetermined level is indicative that the subject is at an elevated risk of developing the inflammatory disease and a level of gelsolin at or above the predetermined level is indicative that the subject is not at an elevated risk of developing the inflammatory disease.
[0011] In some embodiments, the method further comprises performing one or more tests to evaluate the inflammatory disease. Evaluating an inflammatory disease may involve measuring a level of a marker of inflammation in the subject. Examples of markers of inflammation include but are not limited to CRP, soluble intercellular adhesion molecule (sICAM-1), ICAM 3, BL-CAM, LFA-2, VCAM-1, NCAM, PECAM, fibrinogen, serum amyloid A (SAA), lipoprotein associated phospholipase A2 (LpP1A2), sCD40 ligand (sCD40L), myeloperoxidase, Interleukin-6 (IL-6), or Interleukin-8 (IL-8).
[0012] According to another aspect of the invention, a method for characterizing a subject's risk profile of developing a future inflammatory disease (e.g., rheumatoid arthritis in preferred embodiments) is provided. The method comprises obtaining a level of gelsolin in the subject and comparing the level of the gelsolin to a first predetermined value to establish a first risk value. A level of a second marker of inflammation in the subject is obtained and the level of the second marker of inflammation is compared to a second predetermined value to establish a second risk value. The subject's risk profile of developing the inflammatory disease is characterized based upon the combination of the first risk value and the second risk value, wherein the combination of the first risk value and second risk value establishes a third risk value different from said first and second risk values.
[0013] In some embodiments, the subject is an apparently healthy subject.
[0014] In some embodiments, the first predetermined value may be a plurality of predetermined gelsolin level ranges, one of a plurality of ranges being below about 250 mg/L of plasma and another of said ranges being above about 250 mg/L of plasma, and the comparing step comprises determining in which of said plurality of predetermined gelsolin level ranges said subject's gelsolin level falls.
[0015] According to another aspect of the invention, a method for treating a subject having or at risk of developing an inflammatory disease (e.g., rheumatoid arthritis in preferred embodiments) is provided. The method comprises administering an effective amount of gelsolin to the subject in need of such a treatment to treat the subject.
[0016] According to another aspect of the invention, a method for treating a subject having or at risk of developing an inflammatory disease (e.g., rheumatoid arthritis in preferred embodiments) is provided. The method comprises administering an effective amount of gelsolin to the subject in need of such a treatment to raise the level of gelsolin in the subject above a predetermined value.
[0017] In some embodiments, the subject is otherwise free of indications calling for treatment with gelsolin. The gelsolin preferrably is administered orally, sublingually, buccally, intranasally, intravenously, intramuscularly, intraarticularly, intraperitoneally, subcutaneously, or topically. The gelsolin may be administered prophylactically.
[0018] In some embodiments, the treatment methods further comprise administering a second agent for treating the inflammatory disease (e.g., rheumatoid arthritis in preferred embodiments). Examples of agents for treating the inflammatory disease include but are not limited to Alclofenac, Alclometasone Dipropionate, Algestone Acetonide, Alpha Amylase, Amcinafal, Amcinafide, Amfenac Sodium, Amiprilose Hydrochloride, Anakinra, Anirolac, Anitrazafen, Apazone, Balsalazide Disodium, Bendazac, Benoxaprofen, Benzydamine Hydrochloride, Bromelains, Broperamole, Budesonide, Carprofen, Cicloprofen, Cintazone, Cliprofen, Clobetasol Propionate, Clobetasone Butyrate, Clopirac, Cloticasone Propionate, Cormethasone Acetate, Cortodoxone, Cyclooxygenase-2 (COX-2) inhibitor, Deflazacort, Desonide, Desoximetasone, Dexamethasone Dipropionate, Diclofenac Potassium, Diclofenac Sodium, Diflorasone Diacetate, Diflumidone Sodium, Diflunisal, Difluprednate, Diftalone, Dimethyl Sulfoxide, Drocinonide, Endrysone, Enlimomab, Enolicam Sodium, Epirizole, Etodolac, Etofenamate, Felbinac, Fenamole, Fenbufen, Fenclofenac, Fenclorac, Fendosal, Fenpipalone, Fentiazac, Flazalone, Fluazacort, Flufenamic Acid, Flumizole, Flunisolide Acetate, Flunixin, Flunixin Meglumine, Fluocortin Butyl, Fluorometholone Acetate, Fluquazone, Flurbiprofen, Fluretofen, Fluticasone Propionate, Furaprofen, Furobufen, Halcinonide, Halobetasol Propionate, Halopredone Acetate, Ibufenac, Ibuprofen, Ibuprofen Aluminum, Ibuprofen Piconol, Ilonidap, Indomethacin, Indomethacin Sodium, Indoprofen, Indoxole, Intrazole, Isoflupredone Acetate, Isoxepac, Isoxicam, Ketoprofen, Lofemizole Hydrochloride, Lornoxicam, Loteprednol Etabonate, Meclofenamate Sodium, Meclofenamic Acid, Meclorisone Dibutyrate, Mefenamic Acid, Mesalamine, Meseclazone, Methylprednisolone Suleptanate, Morniflumate, Nabumetone, Naproxen, Naproxen Sodium, Naproxol, Nimazone, Olsalazine Sodium, Orgotein, Orpanoxin, Oxaprozin, Oxyphenbutazone, Paranyline Hydrochloride, Pentosan Polysulfate Sodium, Phenbutazone Sodium Glycerate, Pirfenidone, Piroxicam, Piroxicam Cinnamate, Piroxicam Olamine, Pirprofen, Prednazate, Prifelone, Prodolic Acid, Proquazone, Proxazole, Proxazole Citrate, Rimexolone, Romazarit, Salcolex, Salnacedin, Salsalate, Sanguinarium Chloride, Seclazone, Sermetacin, Sudoxicam, Sulindac, Suprofen, Talmetacin, Talniflumate, Talosalate, Tebufelone, Tenidap, Tenidap Sodium, Tenoxicam, Tesicam, Tesimide, Tetrydamine, Tiopinac, Tixocortol Pivalate, Tolmetin, Tolmetin Sodium, Triclonide, Triflumidate, Zidometacin, or Zomepirac Sodium.
[0019] Anti-inflammatory agents also include Cyclooxygenase-2 (COX-2) inhibitors. Cyclooxygenase is an enzyme complex present in most tissues that produces various prostaglandins and thromboxanes from arachidonic acid. Non-steroidal, antiinflammatory drugs exert most of their antiinflammatory, analgesic and antipyretic activity and inhibit hormone-induced uterine contractions and certain types of cancer growth through inhibition of the cyclooxygenase (also known as prostaglandin G/H synthase and/or prostaglandin-endoperoxide synthase). Initially, only one form of cyclooxygenase was known, the “constitutive enzyme” or cyclooxygenase-1 (COX-1). It was originally identified in bovine seminal vesicles.
[0020] Cyclooxygenase-2 (COX-2) has been cloned, sequenced and characterized initially from chicken, murine and human sources (See, e.g., U.S. Pat. No. 5,543,297, issued Aug. 6, 1996 to Cromlish, et al., and assigned to Merck Frosst Canada, Inc., Kirkland, Calif., entitled: “Human cyclooxygenase-2 cDNA and assays for evaluating cyclooxygenase-2 activity”). This enzyme is distinct from the COX-1. COX-2, is rapidly and readily inducible by a number of agents including mitogens, endotoxin, hormones, cytokines and growth factors. As prostaglandins have both physiological and pathological roles, it is believed that the constitutive enzyme, COX-1, is responsible, in large part, for endogenous basal release of prostaglandins and hence is important in their physiological functions such as the maintenance of gastrointestinal integrity and renal blood flow. By contrast, it is believed that the inducible form, COX-2, is mainly responsible for the pathological effects of prostaglandins where rapid induction of the enzyme would occur in response to such agents as inflammatory agents, hormones, growth factors, and cytokines. Therefore, it is believed that a selective inhibitor of COX-2 has similar antiinflammatory, antipyretic and analgesic properties to a conventional non-steroidal antiinflammatory drug, and in addition inhibits hormone-induced uterine contractions and also has potential anti-cancer effects, but with reduced side effects. In particular, such COX-2 inhibitors are believed to have a reduced potential for gastrointestinal toxicity, a reduced potential for renal side effects, a reduced effect on bleeding times and possibly a decreased potential to induce asthma attacks in aspirin-sensitive asthmatic subjects, and are therefore useful according to the present invention.
[0021] A number of selective COX-2 inhibitors are known in the art. Examples of selective COX-2 inhibitors include, for example, celecoxib (Celebrex®), valdecoxib (Bextra®) and rofecoxib (Vioxx®). Selective COX-2 inhibitors also include, but are not limited to, COX-2 inhibitors described in U.S. Pat. No. 5,474,995 “Phenyl heterocycles as COX-2 inhibitors”; U.S. Pat. No. 5,521,213 “Diaryl bicyclic heterocycles as inhibitors of cyclooxygenase-2”; U.S. Pat. No. 5,536,752 “Phenyl heterocycles as COX-2 inhibitors”; U.S. Pat. No. 5,550,142 “Phenyl heterocycles as COX-2 inhibitors”; U.S. Pat. No. 5,552,422 “Aryl substituted 5,5 fused aromatic nitrogen compounds as anti-inflammatory agents”; U.S. Pat. No. 5,604,253 “N-benzylindol-3-yl propanoic acid derivatives as cyclooxygenase inhibitors”; U.S. Pat. No. 5,604,260 “5-methanesulfonamido-1-indanones as an inhibitor of cyclooxygenase-2”; U.S. Pat. No. 5,639,780 N-benzyl indol-3-yl butanoic acid derivatives as cyclooxygenase inhibitors”; U.S. Pat. No. 5,677,318 Diphenyl-1,2-3-thiadiazoles as anti-inflammatory agents”; U.S. Pat. No. 5,691,374 “Diaryl-5-oxygenated-2-(5H)-furanones as COX-2 inhibitors”; U.S. Pat. No. 5,698,584 “3,4-diaryl-2-hydroxy-2,5-dihydrofurans as prodrugs to COX-2 inhibitors”; U.S. Pat. No. 5,710,140 “Phenyl heterocycles as COX-2 inhibitors”; U.S. Pat. No. 5,733,909 “Diphenyl stilbenes as prodrugs to COX-2 inhibitors”; U.S. Pat. No. 5,789,413 “Alkylated styrenes as prodrugs to COX-2 inhibitors”; U.S. Pat. No. 5,817,700 “Bisaryl cyclobutenes derivatives as cyclooxygenase inhibitors”; U.S. Pat. No. 5,849,943 “Stilbene derivatives useful as cyclooxygenase-2 inhibitors”; U.S. Pat. No. 5,861,419 “Substituted pyridines as selective cyclooxygenase-2 inhibitors”; U.S. Pat. No. 5,922,742 “Pyridinyl-2-cyclopenten-1-ones as selective cyclooxygenase-2 inhibitors”; U.S. Pat. No. 5,925,631 “Alkylated styrenes as prodrugs to COX-2 inhibitors”; all of which are commonly assigned to Merck Frosst Canada, Inc. (Kirkland, Calif.). Additional COX-2 inhibitors are also described in U.S. Pat. No. 5,643,933, assigned to G. D. Searle & Co. (Skokie, Ill.), entitled: “Substituted sulfonylphenylheterocycles as cyclooxygenase-2 and 5-lipoxygenase inhibitors.”
[0022] A number of the above-identified COX-2 inhibitors are prodrugs of selective COX-2 inhibitors, and exert their action by conversion in vivo to the active and selective COX-2 inhibitors. The active and selective COX-2 inhibitors formed from the above-identified COX-2 inhibitor prodrugs are described in detail in WO 95/00501, published Jan. 5, 1995, WO 95/18799, published Jul. 13, 1995 and U.S. Pat. No. 5,474,995, issued Dec. 12, 1995. Given the teachings of U.S. Pat. No. 5,543,297, entitled: “Human cyclooxygenase-2 cDNA and assays for evaluating cyclooxygenase-2 activity,” a person of ordinary skill in the art would be able to determine whether an agent is a selective COX-2 inhibitor or a precursor of a COX-2 inhibitor, and therefore part of the present invention.
[0023] In some embodiments, the method further comprises administering a second agent for treating rheumatoid arthritis. Examples of agents for treating rheumatoid arthritis include but are not limited to hydroxychloroquine (Plaquenil), chloroquine (Aralen), methotrexate, sulfasalazine (Azulfidine), Leflunomide (Arava), azathioprine (Imuran), penicillamine (Cuprimine or Depen), Gold salts (Ridaura or Aurolate), minocycline (Dynacin or Minocin), cyclosporine (Neoral or Sandimmune) cyclophosphamide (Cytoxan or Neosar), Etanercept (Enbrel), Infliximab (Remicade), Ahakinra (Kineret) or Adalimumab (Humira).
[0024] According to another aspect of the invention, a method for treating a subject to reduce the risk of an inflammatory disease (e.g., rheumatoid arthritis in preferred embodiments) is provided. The method comprises selecting a subject on the basis that the subject is known to have a below-normal level of gelsolin and administering to the subject an effective amount of gelsolin and/or a second agent to reduce the risk of the subject developing the inflammatory disease (e.g., rheumatoid arthritis in preferred embodiments).
[0025] According to another aspect of the invention, a method for treating a subject to reduce the risk of an inflammatory disease (e.g., rheumatoid arthritis in preferred embodiments) is provided. The method comprises selecting a subject on the basis that the subject is known to have a below-normal level of gelsolin and administering an effective amount of gelsolin and/or a second agent to the subject to raise the level of gelsolin in the subject above a predetermined value.
[0026] In some embodiments, the method further comprises administering to the subject a second agent for treating the inflammatory disease (e.g., rheumatoid arthritis in preferred embodiments). Examples of agents for treating the inflammatory disease and rheumatoid arthritis are listed above.
[0027] According to yet another aspect of the invention, a method for treating a subject with a below-normal level of gelsolin is provided. The method comprises treating the subject with a first therapy for treating or reducing the risk of an inflammatory disease (e.g., rheumatoid arthritis in preferred embodiments). A level of gelsolin in the subject is obtained. The level of gelsolin is compared to a predetermined value corresponding to a predetermined level of gelsolin (e.g., in an apparently healthy control population). If the predetermined level of gelsolin is not reached, the subject is treated with a second agent for treating or reducing the risk of the inflammatory disease (e.g., rheumatoid arthritis in preferred embodiments) until the predetermined level of gelsolin is reached.
[0028] A “below-normal level of gelsolin” is a gelsolin level is at least 10% less than the measured mean level for a given population of subjects. The mean gelsolin level can depend upon the particular population of subjects. For example, an apparently healthy population will have a different “normal” range of gelsolin than will a population of subjects which have had a prior condition. In some embodiments, the gelsolin level is at least 10% less than the measured mean level for a given population of subjects. In other embodiments, the gelsolin level is at least 20% less than the measured mean level for a given population of subjects. In still other embodiments, the gelsolin level is at least 30%, 40%, 50%, 60%, 70%, 80%, 90%, 95%, 99% or 100% less than the measured mean level for a given population of subjects. In one of the embodiments, the gelsolin level is below about 250 mg/L of plasma. In other important embodiments, the gelsolin level is below about 2.4 μM/L (micromoles/Liter) of plasma.
[0029] In some embodiments the subject is otherwise free of indications calling for treatment with the agent. When the agent is gelsolin, a subject free of indications calling for treatment with gelsolin is a subject who has no signs or symptoms calling for treatment with gelsolin. Gelsolin is indicated for the treatment of sepsis and infections. Gelsolin is also indicated for the treatment of actin-related disorders such as Adult Respiratory Distress Syndrome (ARDS), fulminant hepatic necrosis, acute renal failure, muscle injury, disorders characterized by elevated levels of BUN and/or creatinine. Actin-related disorders are known to those of ordinary skill in the art.
[0030] In other embodiments, the subject is apparently healthy. As used herein an “apparently healthy subject” is a subject who has no signs and/or symptoms of a disease.
[0031] According to another aspect of the invention, a method for evaluating the efficacy of a therapy for treating or reducing the risk of an inflammatory disease (e.g., rheumatoid arthritis in preferred embodiments) in a subject is provided. The method comprises obtaining a level of gelsolin in a subject undergoing therapy with an agent to treat or reduce the risk of inflammatory disease (e.g., rheumatoid arthritis in preferred embodiments). The level of gelsolin obtained is compared to a predetermined value corresponding to a level of gelsolin (e.g., in an apparently healthy control population). A determination of whether the level of gelsolin is above the predetermined level is indicative of whether the therapy is efficacious. In some embodiments, obtaining a level of the gelsolin is repeated so as to monitor the subject's level of the gelsolin over time.
[0032] The therapy may be with gelsolin, Alclofenac, Alclometasone Dipropionate, Algestone Acetonide, Alpha Amylase, Amcinafal, Amcinafide, Amfenac Sodium, Amiprilose Hydrochloride, Anakinra, Anirolac, Anitrazafen, Apazone, Balsalazide Disodium, Bendazac, Benoxaprofen, Benzydamine Hydrochloride, Bromelains, Broperamole, Budesonide, Carprofen, Cicloprofen, Cintazone, Cliprofen, Clobetasol Propionate, Clobetasone Butyrate, Clopirac, Cloticasone Propionate, Cormethasone Acetate, Cortodoxone, Cyclooxygenase-2 (COX-2) inhibitor, Deflazacort, Desonide, Desoximetasone, Dexamethasone Dipropionate, Diclofenac Potassium, Diclofenac Sodium, Diflorasone Diacetate, Diflumidone Sodium, Diflunisal, Difluprednate, Diftalone, Dimethyl Sulfoxide, Drocinonide, Endrysone, Enlimomab, Enolicam Sodium, Epirizole, Etodolac, Etofenamate, Felbinac, Fenamole, Fenbufen, Fenclofenac, Fenclorac, Fendosal, Fenpipalone, Fentiazac, Flazalone, Fluazacort, Flufenamic Acid, Flumizole, Flunisolide Acetate, Flunixin, Flunixin Meglumine, Fluocortin Butyl, Fluorometholone Acetate, Fluquazone, Flurbiprofen, Fluretofen, Fluticasone Propionate, Furaprofen, Furobufen, Halcinonide, Halobetasol Propionate, Halopredone Acetate, Ibufenac, Ibuprofen, Ibuprofen Aluminum, Ibuprofen Piconol, Ilonidap, Indomethacin, Indomethacin Sodium, Indoprofen, Indoxole, Intrazole, Isoflupredone Acetate, Isoxepac, Isoxicam, Ketoprofen, Lofemizole Hydrochloride, Lornoxicam, Loteprednol Etabonate, Meclofenamate Sodium, Meclofenamic Acid, Meclorisone Dibutyrate, Mefenamic Acid, Mesalamine, Meseclazone, Methylprednisolone Suleptanate, Morniflumate, Nabumetone, Naproxen, Naproxen Sodium, Naproxol, Nimazone, Olsalazine Sodium, Orgotein, Orpanoxin, Oxaprozin, Oxyphenbutazone, Paranyline Hydrochloride, Pentosan Polysulfate Sodium, Phenbutazone Sodium Glycerate, Pirfenidone, Piroxicam, Piroxicam Cinnamate, Piroxicam Olamine, Pirprofen, Prednazate, Prifelone, Prodolic Acid, Proquazone, Proxazole, Proxazole Citrate, Rimexolone, Romazarit, Salcolex, Salnacedin, Salsalate, Sanguinarium Chloride, Seclazone, Sermetacin, Sudoxicam, Sulindac, Suprofen, Talmetacin, Talniflumate, Talosalate, Tebufelone, Tenidap, Tenidap Sodium, Tenoxicam, Tesicam, Tesimide, Tetrydamine, Tiopinac, Tixocortol Pivalate, Tolmetin, Tolmetin Sodium, Triclonide, Triflumidate, Zidometacin, Zomepirac Sodium, hydroxychloroquine (Plaquenil), chloroquine (Aralen), methotrexate, sulfasalazine (Azulfidine), Leflunomide (Arava), azathioprine (Imuran), penicillamine (Cuprimine or Depen), Gold salts (Ridaura or Aurolate), minocycline (Dynacin or Minocin), cyclosporine (Neoral or Sandimmune) cyclophosphamide (Cytoxan or Neosar), Etanercept (Enbrel), Infliximab (Remicade), Anakinra (Kineret) or Adalimumab (Humira).
[0033] According to still another aspect of the invention, a method for deciding on the course of a therapy in a subject is provided. The method comprises obtaining a level of gelsolin in a subject undergoing a therapy to treat or reduce the risk of an inflammatory disease (e.g., rheumatoid arthritis in preferred embodiments). The level of gelsolin is compared to a predetermined value corresponding to a level of gelsolin (e.g., in an apparently healthy control population). Whether the level of gelsolin obtained is at or above or at or below the predetermined level is determined and the course of therapy is decided based on such determination. In some embodiments, obtaining a level of gelsolin is repeated so as to monitor the subject's level of gelsolin over time.
[0034] The following embodiments apply to various aspects of the invention set forth herein unless indicated otherwise.
[0035] The inflammatory disease may be arthritis, rheumatoid arthritis, asthma, inflammatory bowel disease (Crohn's disease or ulcerative colitis), chronic obstructive pulmonary disease (COPD), allergic rhinitis, vasculitis (polyarteritis nodosa, temporal arteritis, Wegener's granulomatosus, Takayasu's arteritis, or Behcet syndrome), inflammatory neuropathy, psoriasis, systemic lupus erythematosis (SLE), chronic thyroiditis, Hashimoto's thyroiditis, Addison's disease, polymyalgia rheumatica, Sjogren's syndrome, or Churg-Strauss syndrome. In some important embodiments, the inflammatory disease is rheumatoid arthritis.
[0036] The level of gelsolin may be in a body fluid of the subject. Examples of body fluids include but are not limited to blood, plasma, serum, urine, synovial fluid, or alveolar fluid.
[0037] The level of gelsolin may be in a body tissue of the subject. The body tissue may be joint, gastrointestinal, thyroid, adrenal, vascular, pulmonary, renal, cardiac, skin, ocular, brain pancreatic, liver, nerve, or muscle tissue. In some embodiments, the subject is an apparently healthy subject.
[0038] In some embodiments, the predetermined value is 250 mg/L of plasma or lower. In some embodiments, the predetermined value of gelsolin is about 240 mg/L, 230 mg/L, 220 mg/L, 210 mg/L, 200 mg/L, 190 mg/L, 180 mg/L, 170 mg/L, 160 mg/L, 150 mg/L, 140 mg/L, 130 mg/L, 120 mg/L, 110 mg/L, 100 mg/L, 90 mg/L, 80 mg/L, 70 mg/L, 60 mg/L, 50 mg/L, 40 mg/L, 30 mg/L, 20 mg/L, or 10 mg/L of plasma or lower.
[0039] In some other embodiments, the predetermined value is 2.4 μM/L of plasma or lower. In some embodiments, the predetermined value of gelsolin is about 2.3 μM/L, 2.2 μM/L, 2.1 μM/L, 2.0 μM/L, 1.9 μM/L, 1.8 μM/L, 1.7 μM/L, 1.6 μM/L, 1.5 μM/L, 1.4 μM/L, 1.3 μM/L, 1.2 μM/L, 1.1 μM/L, 1.0 μM/L, 0.9 μM/L, 0.8 μM/L, 0.7 μM/L, 0.6 μM/L, 0.5 μM/L, 0.4 μM/L, 0.3 μM/L, 0.2 μM/L of plasma or lower.
[0040] Each of the limitations of the invention can encompass various embodiments of the invention. It is, therefore, anticipated that each of the limitations of the invention involving any one element or combinations of elements can be included in each aspect of the invention. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including”, “comprising”, or “having”, “containing”, “involving”, and variations thereof herein, is meant to encompass the items listed thereafter and equivalents thereof as well as additional items.
[0041] These and other aspects of the inventions, as well as various advantages and utilities will be apparent with reference to the Detailed Description of the Invention. Each aspect of the invention can encompass various embodiments as will be understood.
[0042] All documents identified in this application are incorporated in their entirety herein by reference.
BRIEF DESCRIPTION OF THE DRAWINGS
[0043] FIG. 1 is a histogram showing that plasma gelsolin (pGSN) concentration is decreased in patients with rheumatoid arthritis (RA) compared to healthy controls and lower in synovial fluid than in blood in patients with RA.
[0044] FIG. 2 is an immunoblot with an antibody specific for the plasma isoform of gelsolin showing that the gelsolin present in the synovial fluid (SF) of RA patients is composed mainly of the plasma isoform.
[0045] FIG. 3 is a set of histograms showing that plasma gelsolin (pGSN) concentrations are decreased in mouse models of septic arthritis: A) Staphylococcus aureus ( S. aureus ) induced arthritis, B) sepsis induced by Staphylococcus aureus ( S. aureus ) and C) Streptococcus agalactiae (Str. agalactiae) induced septic arthritis. The decrease occurred at the earliest time-point tested (two days post-inoculation).
[0046] It is to be understood that the drawings are not required for enablement of the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0047] This invention is based on the surprising discovery that plasma gelsolin levels are reduced in blood samples from human subjects with an inflammatory disease, rheumatoid arthritis (RA). It is hypothesized that plasma gelsolin levels fall in response to the initial (unknown) injury inflicted by the agency causing RA. Therefore, peripheral gelsolin replacement can ameliorate the secondary injury mediated by various inflammatory cells. It is believed that the pattern of gelsolin depletion to predict disease and the use of gelsolin to treat disease is true for inflammatory diseases in general.
[0048] Thus, the invention involves, in some aspects, administering gelsolin to a subject to treat an inflammatory disease in the subject. The term “treat” or “treatment” is intended to include prophylaxis, amelioration, prevention or cure from the disease.
[0049] As used herein the term “subject” means any mammal that may be in need of treatment. Subjects include but are not limited to: humans, non-human primates, cats, dogs, sheep, pigs, horses, cows, rodents such as mice, hamsters, and rats. Preferred subjects are human subjects.
[0050] As used herein the term “gelsolin” encompasses wild type gelsolin (GenBank accession No.: X04412), isoforms, analogs, variants, fragments or functional derivatives of gelsolin.
[0051] Gelsolin (GSN), unlike other mammalian proteins, has both cytoplasmic (cGSN) and secreted or exported isoforms, also called plasma gelsolin (pGSN), which are derived by alternative splicing of the message from a single gene (Sun et al. J. Biol. Chem. 274:33179-33182 (1999)). As used herein, gelsolin isoforms include versions of gelsolin with some small differences in their amino acid sequences, usually a splice variant or the result of some posttranslational modification.
[0052] Gelsolin encompasses native as well as synthetic and recombinant gelsolin and gelsolin analogs. Gelsolin is an abundant secretory protein (Yin, H. L., Kwiatkowski, D. J., Mole, J. E. & Cole, F. S. (1984) J Biol Chem 259, 5271-6). The exported isoform of gelsolin, pGSN, has 25 additional amino acids and originates from alternative splicing of a single gene (Kwiatkowski, D. J., Stossel, T. P., Orkin, S. H., Mole, J. E., Colten, H. R. & Yin, H. L. (1986) Nature 323, 455-8). Recombinant human gelsolin (rhGSN) (Biogen IDEC, Inc., Cambridge, Mass.) is produced in E. coli , and though it has the same primary structure as the native protein, under standard conditions of purification, it differs from natural human plasma gelsolin by a disulfide bond that is present in the natural protein. The recombinant protein is, therefore, properly oxidized after purification, and its structure and functions are indistinguishable from human plasma gelsolin (Wen et. al., Biochemistry 35:9700-9709 (1996)). In some of the important therapeutic aspects and embodiments of the invention, the use of rhGSN is preferred. In some of the important diagnostic aspects and embodiments of the invention, the use of pGSN is preferred.
[0053] A “gelsolin analog” refers to a compound substantially similar in function to either the native gelsolin or to a fragment thereof. Gelsolin analogs include biologically active amino acid sequences substantially similar to the gelsolin sequences and may have substituted, deleted, elongated, replaced, or otherwise modified sequences that possess bioactivity substantially similar to that of gelsolin. For example, an analog of gelsolin is one which does not have the same amino acid sequence as gelsolin but which is sufficiently homologous to gelsolin so as to retain the bioactivity of gelsolin. Bioactivity can be determined, for example, by determining the properties of the gelsolin analog and/or by determining the ability of the gelsolin analog to treat or prevent rheumatoid arthritis. One example of a gelsolin bioactivity assay is gelsolin's ability to stimulate actin nucleation. Gelsolin bioactivity assays are described in the Example and are known to those of ordinary skill in the art.
[0054] A “fragment” is meant to include any portion of a gelsolin molecule which provides a segment of gelsolin which maintains the bioactivity of gelsolin; the term is meant to include gelsolin fragments which are made from any source, such as, for example, from naturally-occurring peptide sequences, synthetic or chemically-synthesized peptide sequences, and genetically engineered peptide sequences.
[0055] A “variant” of gelsolin is meant to refer to a compound substantially similar in structure and bioactivity either to native gelsolin, or to a fragment thereof. The term variant encompasses the gelsolin family of proteins. The gelsolin family of proteins is a group of actin binding proteins sharing repeats of about 15 kDa homologous domains that adopt a similar fold. Examples gelsolin family proteins include but are not limited to advillin, villin, capG, flightless proteins, fragmin, severin, adseverin, protovillin, and supervillin.
[0056] A “functional derivative” of gelsolin is a derivative which possesses a bioactivity that is substantially similar to the bioactivity of gelsolin. By “substantially similar” is meant activity which is quantitatively different but qualitatively the same. For example, a functional derivative of gelsolin could contain the same amino acid backbone as gelsolin but also contains other modifications such as post-translational modifications such as, for example, bound phospholipids, or covalently linked carbohydrate, depending on the necessity of such modifications for the performance of the diagnostic assay or therapeutic treatment. As used herein, the term is also meant to include a chemical derivative of gelsolin. Such derivatives may improve gelsolin's solubility, absorption, biological half life, etc. The derivatives may also decrease the toxicity of gelsolin, or eliminate or attenuate any undesirable side effect of gelsolin, etc. Chemical moieties capable of mediating such effects are disclosed in Remington's Pharmaceutical Sciences (1980). Procedures for coupling such moieties to a molecule such as gelsolin are well known in the art. The term “functional derivative” is intended to include the “fragments,” “variants,” “analogues,” or “chemical derivatives” of gelsolin.
[0057] The invention involves in some aspects, methods for treating an inflammatory disease (e.g., rheumatoid arthritis in preferred embodiments) in a subject. The subject is known to have, is suspected of having, or is at risk of having the inflammatory disease. The gelsolin is administered in an amount effective to treat the inflammatory disease in the subject.
[0058] A response to a treatment method of the invention can, for example, be measured by determining the physiological effects of the treatment, such as the decrease or lack of symptoms following administration of the treatment.
[0059] In another aspect of the invention, a method for monitoring therapy in a subject is provided. The method involves obtaining a level of gelsolin in a subject undergoing therapy to treat an inflammatory disease (e.g., rheumatoid arthritis in preferred embodiments). The level of gelsolin is compared to a predetermined value corresponding to a control level of gelsolin (e.g., in an apparently healthy population). A determination of whether the level of gelsolin is at or below a predetermined level is indicative of whether the subject would benefit from continued therapy with the same therapy or would benefit from a change in therapy. In some embodiments, obtaining a level of gelsolin is repeated so as to monitor the subject's levels of gelsolin over time. In some embodiments, the subject may have been undergoing the therapy for at least 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 weeks or more. In some embodiments, the subject may have been undergoing the therapy for at least 3, 4, 5, 6 months, or more.
[0060] A change in therapy with gelsolin refers to an increase in the dose of the gelsolin, a switch from one gelsolin to another gelsolin, a switch from gelsolin to another agent, the addition of another agent to the gelsolin therapeutic regimen, or a combination thereof.
[0061] According to another aspect of the invention, a method for evaluating the efficacy of a therapy for treating or reducing the risk of an inflammatory disease (e.g., rheumatoid arthritis in preferred embodiments) is provided. The method involves obtaining a level of gelsolin in a subject undergoing therapy to treat the inflammatory disease. The level of gelsolin is compared to a predetermined value corresponding to a control level of gelsolin (e.g., in an apparently healthy population). A determination that the level of gelsolin is at or above a predetermined level is indicative that the therapy is efficacious. In some embodiments, the subject may have been undergoing the therapy for at least at least 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 weeks or more. In some embodiments, the subject may have been undergoing the therapy for at least 3, 4, 5, 6 months, or more.
[0062] One aspect of the invention is directed to the measurement of gelsolin to guide treatments in order to improve outcome in subjects. On-therapy levels of gelsolin have predictive value for response to treatments of an inflammatory disease (e.g., rheumatoid arthritis in preferred embodiments). The on-therapy levels of gelsolin are additive to prior art predictors of outcome of the disease.
[0063] Subjects who would benefit from this aspect of this invention are subjects who are undergoing therapy to treat or prevent the inflammatory disease such as, for example, rheumatoid arthritis (i.e., a subject “on-therapy”). A subject on-therapy is a subject who already has been diagnosed and is in the course of treatment with a therapy for treating an inflammatory disease such as rheumatoid arthritis. The therapy can be any of the therapeutic agents referred to herein. The therapy also can be non-drug treatments. In important embodiments, the therapy is one which increases levels of gelsolin. In a particularly important embodiment, the therapy is a therapy with gelsolin. Preferred subjects are human subjects. The subject most likely to benefit from this invention is a human subject on-therapy and who has a gelsolin level at or below about 250 mg/L (or 2.4 μM/L) of plasma.
[0064] In some embodiments, the subject already has the disease. In some embodiments, the subject may be at an elevated risk of having the disease.
[0065] Risk factors for diseases are known to those of ordinary skill in the art. For example, risk factors for rheumatoid arthritis include: age (between 25 and 45 years), female gender, Caucasian or native American ethnicity, obesity, and a positive family history. The degree of risk of rheumatoid arthritis depends on the multitude and the severity or the magnitude of the risk factors that the subject has. Risk charts and prediction algorithms are available for assessing the risk of inflammatory diseases such as rheumatoid arthritis in a subject based on the presence and severity of risk factors. In some embodiments, the subject who is at an elevated risk of having the inflammatory disease may be an apparently healthy subject. An apparently healthy subject is a subject who has no signs or symptoms of disease.
[0066] Other methods of assessing the risk of an inflammatory disease in a subject are known by those of ordinary skill in the art.
[0067] The preferred treatment of the instant invention is gelsolin. Gelsolin may be administered alone, in a pharmaceutical composition or combined with other therapeutic regimens. Gelsolin and optionally other therapeutic agent(s) may be administered simultaneously or sequentially. When the other therapeutic agents are administered simultaneously they can be administered in the same or separate formulations, but are administered at the same time. The other therapeutic agents may be administered sequentially with one another and with gelsolin when the administration of the other therapeutic agents and the gelsolin is temporally separated. The separation in time between the administration of these compounds may be a matter of minutes or it may be longer.
[0068] In practicing certain methods of the present invention, it is required to obtain a level of gelsolin in a subject. This level then is compared to a predetermined value, wherein the level of gelsolin in comparison to the predetermined value is indicative of the likelihood that the subject will benefit from continued therapy. The subject then can be characterized in terms of the net benefit likely to be obtained from a change in therapy.
[0069] The level of the gelsolin for the subject can be obtained by any art recognized method. Typically, the level is determined by measuring the level of gelsolin in a body fluid, for example, blood, serum, plasma, lymph, saliva, urine, synovial fluid and the like. The level can be determined by ELISA, or other immunoassays or other conventional techniques for determining the presence of gelsolin. Conventional methods may include sending a sample(s) of a subject's body fluid to a commercial laboratory for measurement. Methods for measuring gelsolin are described in the Example.
[0070] The invention also involves comparing the level of gelsolin for the subject with a predetermined value. The predetermined value can take a variety of forms. It can be single cut-off value, such as a median or mean. It can be established based upon comparative groups, such as, for example, where the risk in one defined group is double the risk in another defined group. It can be a range, for example, where the tested population is divided equally (or unequally) into groups, such as a low-risk group, a medium-risk group and a high-risk group, or into quartiles, the lowest quartile being subjects with the highest risk and the highest quartile being subjects with the lowest risk, or into tertiles the lowest tertile being subjects with the highest risk and the highest tertile being subjects with the lowest risk. The predetermined value may be a cut-off value which is predetermined by the fact that a group having a gelsolin level no less than the cut-off value demonstrates a statistically significant increase in the risk of developing an inflammatory disease (e.g., rheumatoid arthritis in preferred embodiments) as compared to a comparative group. In some embodiments the comparative group is a group having a lower level of gelsolin.
[0071] The predetermined value can depend upon the particular population of subjects selected. For example, an apparently healthy population may have a different ‘normal’ range of gelsolin than will populations of subjects which have other conditions. Accordingly, the predetermined values selected may take into account the category in which a subject falls. Appropriate ranges and categories can be selected with no more than routine experimentation by those of ordinary skill in the art. The preferred body fluid is blood. In some embodiments, the predetermined value of gelsolin is about 250 mg/L of plasma or lower. In some embodiments, the predetermined value of gelsolin is about 240 mg/L, 230 mg/L, 220 mg/L, 210 mg/L, 200 mg/L, 190 mg/L, 180 mg/L, 170 mg/L, 160 mg/L, 150 mg/L, 140 mg/L, 130 mg/L, 120 mg/L, 110 mg/L, 100 mg/L, 90 mg/L, 80 mg/L, 70 mg/L, 60 mg/L, 50 mg/L, 40 mg/L, 30 mg/L, 20 mg/L, or 10 mg/L of plasma or lower.
[0072] In some embodiments, the predetermined value of gelsolin is about 2.4 μM/L of plasma or lower. In some embodiments, the predetermined value of gelsolin is about 2.3 μM/L, 2.2 μM/L, 2.1 μM/L, 2.0 μM/L, 1.9 μM/L, 1.8 μM/L, 1.7 μM/L, 1.6 μM/L, 1.5 μM/L, 1.4 μM/L, 1.3 μM/L, 1.2 μM/L, 1.1 μM/L, 1.0 μM/L, 0.9 μM/L, 0.8 μM/L, 0.7 μM/L, 0.6 μM/L, 0.5 μM/L, 0.4 μM/L, 0.3 μM/L, 0.2 μM/L of plasma or lower.
[0073] An important predetermined value of gelsolin is a value that is the average for a healthy subject population (i.e., subjects who have no signs and symptoms of disease). The predetermined value will depend, of course, upon the characteristics of the subject population in which the subject lies. In characterizing risk, numerous predetermined values can be established.
[0074] Presently, there are commercial sources which produce reagents for assays for gelsolin. These include, for example, Cytoskeleton (Denver, Colo.), Sigma (St. Louis, Mo.) and Calbiochem (San Diego, Calif.)
[0075] In some embodiments, the invention further comprises measuring the level of gelsolin together with a level of a second marker of an inflammatory disease (e.g., rheumatoid arthritis in preferred embodiments). Markers for inflammatory diseases are known to those of ordinary skill in the art and examples of which are described above. Examples of markers for rheumatoid arthritis include, for example, anti cyclic citrullinated peptide (anti-CCP) antibodies, HLA-DR4, and C-reactive protein (CRP). A level of gelsolin in the subject is obtained. The level of gelsolin is compared to a predetermined value to establish a first risk value. A level of the second marker inflammatory disease in the subject is also obtained. The level of the second marker inflammatory disease in the subject is compared to a second predetermined value to establish a second risk value. The subject's risk profile of developing the inflammatory disease (e.g., rheumatoid arthritis in preferred embodiments) then is characterized based upon the combination of the first risk value and the second risk value, wherein the combination of the first risk value and second risk value establishes a third risk value different from the first and second risk values. In some embodiments, the third risk value is greater than either of the first and second risk values. The preferred subjects for testing and predetermined values are as described above. The disease may be any of the inflammatory disease described above.
[0076] The invention provides methods for determining whether a subject will benefit from continued therapy or would benefit from a change in therapy. The benefit is typically a reduction in the signs and symptoms or a faster recovery from the manifestations of the disease. Signs, symptoms and manifestations of disease are known to those of ordinary skill in the art. For example, in rheumatoid arthritis, signs and symptoms of the disease include pain, swelling and tenderness in the affected joint(s).
[0077] These methods have important implications for patient treatment and also for the clinical development of new therapies. Determining whether a subject will benefit from continued therapy or would benefit from a change in therapy is clinically useful. One example of clinical usefulness of the methods of this invention includes identifying subjects who are less likely or more likely to respond to a therapy. The methods of the invention are also useful in predicting or determining that a subject would benefit from continued therapy or would benefit from a change in therapy. Health care practitioners select therapeutic regimens for treatment based upon the expected net benefit to the subject. The net benefit is derived from the risk to benefit ratio. The present invention permits the determination of whether a subject will benefit from continued therapy or would benefit from a change in therapy, thereby aiding the physician in selecting a therapy.
[0078] Another example of clinical usefulness, in the case of human subjects for example, includes aiding clinical investigators in the selection for clinical trials of subjects with a high likelihood of obtaining a net benefit. It is expected that clinical investigators now will use the present invention for determining entry criteria for clinical trials.
[0079] A subject who would benefit from continued therapy is a subject whose on-therapy level of gelsolin reaches a certain predetermined value or whose level of gelsolin is increasing. Predetermined values of gelsolin are described above. A subject who would benefit from a change in therapy is a subject whose on-therapy level of the gelsolin did not reach a certain predetermined value or whose on-therapy level of gelsolin is not increasing.
[0080] As used herein, a “change in therapy” refers to an increase or decrease in the dose of the existing therapy, a switch from one therapy to another therapy, an addition of another therapy to the existing therapy, or a combination thereof. A switch from one therapy to another may involve a switch to a therapy with a high risk profile but where the likelihood of expected benefit is increased. In some embodiments, preferred therapies are therapies that increase the levels of gelsolin. A subject who would benefit from a change in therapy by increasing the dose of the existing therapy is a subject who, for example, was on the therapy but was not receiving the maximum tolerated dose or the maximum allowed dose of the therapy and whose level of gelsolin did not reach a certain predetermined value. In such instances the dose of the existing therapy is increased until the level of gelsolin reaches a certain predetermined value. In some instances, the dose of the existing therapy is increased from the existing dose to a higher dose that is not the maximum tolerated dose nor the maximum allowed dose of the therapy. In other instances, the dose is increased to the maximum tolerated or to the maximum allowed dose of the therapy. A subject who would benefit from a change in therapy by decreasing the dose of the existing therapy is, for example, a subject whose on-therapy level of gelsolin reaches or can reach a certain predetermined value with a lower dose of the therapy.
[0081] A subject who would benefit from a switch from one therapy to another therapy is, for example, a subject who was on the maximum tolerated dose or the maximum allowed dose of the therapy and whose level of gelsolin did not reach a certain predetermined value. Another example is a subject was not on the maximum tolerated or the maximum allowed dose of the therapy but was determined by a health care practitioner to more likely benefit from another therapy. Such determinations are based, for example, on the development in the subject of unwanted side effects on the initial therapy or a lack of response to the initial therapy.
[0082] A subject who would benefit from a change in therapy by the addition of another therapy to the existing therapy is, for example, a subject who was on a therapy but whose level of gelsolin did not reach a certain predetermined value. In such instances, another therapy is added to the existing therapy. The therapy that is added to the existing therapy can have a different mechanism of action in increasing the level of gelsolin than the existing therapy. In some instances, a combination of the aforementioned changes in therapy may be used.
[0083] The invention also provides methods for determining the efficacy of a therapy. The efficacy is typically the efficacy of the therapy in increasing the level of gelsolin. This is sometimes also referred to as a positive response or a favorable response. Efficacy can be determined by a gelsolin blood test(s) to determine whether gelsolin levels are increased as a result of therapy. In some embodiments efficacy determination is based on the efficacy of a therapy in increasing both gelsolin and normalizing levels of markers of inflammation and/or normalizing white blood cell (WBC) counts.
[0084] The gelsolin measurement is typically reported in μM/L (micromoles/Liter), mg/dl (milligrams/deciliter), or mg/L (milligrams/Liter).
[0085] The invention also provides methods for deciding on the course of a therapy in a subject undergoing therapy for an inflammatory disease such as rheumatoid arthritis. Such a course of therapy is decided on the basis of the level of gelsolin. In some embodiments, the subject already has the disease or is at risk of having the inflammatory disease. In some embodiments, the subject is at an elevated risk of having the inflammatory disease the subject has one or more risk factors to have the disease.
[0086] The amount of a treatment may be varied for example by increasing or decreasing the amount of gelsolin or pharmacological agent or a therapeutic composition, by changing the therapeutic composition administered, by changing the route of administration, by changing the dosage timing and so on. The effective amount will vary with the particular condition being treated, the age and physical condition of the subject being treated, the severity of the condition, the duration of the treatment, the nature of the concurrent therapy (if any), the specific route of administration, and like factors are within the knowledge and expertise of the health practitioner. For example, an effective amount can depend upon the duration the individual has had the inflammatory disease.
[0087] An effective amount is a dosage of the therapeutic agent sufficient to provide a medically desirable result. An effective amount may also, for example, depend upon the degree to which an individual has abnormally decreased levels of gelsolin. It should be understood that the therapeutic agents of the invention are used to treat or prevent the inflammatory disease (such as rheumatoid arthritis), that is, they may be used prophylactically in subjects at risk of developing the inflammatory disease (such as rheumatoid arthritis). Thus, an effective amount is that amount which can lower the risk of, slow or perhaps prevent altogether the development of the inflammatory disease (such as rheumatoid arthritis). It will be recognized when the therapeutic agent is used in acute circumstances, it is used to prevent one or more medically undesirable results that typically flow from such adverse events.
[0088] The factors involved in determining an effective amount are well known to those of ordinary skill in the art and can be addressed with no more than routine experimentation. It is generally preferred that a maximum dose of the pharmacological agents of the invention (alone or in combination with other therapeutic agents) be used, that is, the highest safe dose according to sound medical judgment. It will be understood by those of ordinary skill in the art however, that a patient may insist upon a lower dose or tolerable dose for medical reasons, psychological reasons or for virtually any other reasons.
[0089] The therapeutically effective amount of a pharmacological agent of the invention is that amount effective to treat the inflammatory disease. For example, in the case of rheumatoid arthritis, the desired response is inhibiting the progression of rheumatoid arthritis. This may involve only slowing the progression of rheumatoid arthritis temporarily, although more preferably, it involves halting the progression of the rheumatoid arthritis permanently. This can be monitored by routine diagnostic methods known to those of ordinary skill in the art. The desired response to treatment of rheumatoid arthritis also can be delaying the onset or even preventing the onset of rheumatoid arthritis.
[0090] The pharmacological agents used in the methods of the invention are preferably sterile and contain an effective amount of gelsolin for producing the desired response in a unit of weight or volume suitable for administration to a subject. The doses of pharmacological agents administered to a subject can be chosen in accordance with different parameters, in particular in accordance with the mode of administration used and the state of the subject. Other factors include the desired period of treatment. In the event that a response in a subject is insufficient at the initial doses applied, higher doses (or effectively higher doses by a different, more localized delivery route) may be employed to the extent that patient tolerance permits. The dosage of a pharmacological agent may be adjusted by the individual physician or veterinarian, particularly in the event of any complication. A therapeutically effective amount typically varies from 0.01 mg/kg to about 1000 mg/kg, preferably from about 0.1 mg/kg to about 500 mg/kg, and most preferably from about 0.2 mg/kg to about 250 mg/kg, in one or more dose administrations daily, for one or more days.
[0091] Gelsolin and optionally other therapeutics may be administered per se or in the form of a pharmaceutically acceptable salt.
[0092] Various modes of administration are known to those of ordinary skill in the art which effectively deliver the pharmacological agents of the invention to a desired tissue, cell, or bodily fluid. The administration methods are discussed elsewhere in the application. The invention is not limited by the particular modes of administration disclosed herein. Standard references in the art (e.g., Remington's Pharmaceutical Sciences, 20th Edition, Lippincott, Williams and Wilkins, Baltimore Md., 2001) provide modes of administration and formulations for delivery of various pharmaceutical preparations and formulations in pharmaceutical carriers. Other protocols which are useful for the administration of pharmacological agents of the invention will be known to one of ordinary skill in the art, in which the dose amount, schedule of administration, sites of administration, mode of administration and the like vary from those presented herein.
[0093] Administration of pharmacological agents of the invention to mammals other than humans, e.g. for testing purposes or veterinary therapeutic purposes, is carried out under substantially the same conditions as described above. It will be understood by one of ordinary skill in the art that this invention is, applicable to both human and animal diseases. Thus, this invention is intended to be used in husbandry and veterinary medicine as well as in human therapeutics.
[0094] When administered, the pharmaceutical preparations of the invention are applied in pharmaceutically-acceptable amounts and in pharmaceutically-acceptable compositions. The term “pharmaceutically acceptable” means a non-toxic material that does not interfere with the effectiveness of the biological activity of the active ingredients. Such preparations may routinely contain salts, buffering agents, preservatives, compatible carriers, and optionally other therapeutic agents. When used in medicine, the salts should be pharmaceutically acceptable, but non-pharmaceutically acceptable salts may conveniently be used to prepare pharmaceutically-acceptable salts thereof and are not excluded from the scope of the invention. Such pharmacologically and pharmaceutically-acceptable salts include, but are not limited to, those prepared from the following acids: hydrochloric, hydrobromic, sulfuric, nitric, phosphoric, maleic, acetic, salicylic, citric, formic, malonic, succinic, and the like. Also, pharmaceutically-acceptable salts can be prepared as alkaline metal or alkaline earth salts, such as sodium, potassium or calcium salts.
[0095] A pharmacological agent or composition may be combined, if desired, with a pharmaceutically-acceptable carrier. The term “pharmaceutically-acceptable carrier” as used herein means one or more compatible solid or liquid fillers, diluents or encapsulating substances which are suitable for administration into a human. The term “carrier” denotes an organic or inorganic ingredient, natural or synthetic, with which the active ingredient is combined to facilitate the application. The components of the pharmaceutical compositions also are capable of being co-mingled with the pharmacological agents of the invention, and with each other, in a manner such that there is no interaction which would substantially impair the desired pharmaceutical efficacy.
[0096] The pharmaceutical compositions may contain suitable buffering agents, as described above, including: acetate, phosphate, citrate, glycine, borate, carbonate, bicarbonate, hydroxide (and other bases) and pharmaceutically acceptable salts of the foregoing compounds. The pharmaceutical compositions also may contain, optionally, suitable preservatives, such as: benzalkonium chloride, chlorobutanol, parabens and thimerosal.
[0097] The pharmaceutical compositions may conveniently be presented in unit dosage form and may be prepared by any of the methods well known in the art of pharmacy. All methods include the step of bringing the active agent into association with a carrier, which constitutes one or more accessory ingredients. In general, the compositions are prepared by uniformly and intimately bringing the active compound into association with a liquid carrier, a finely divided solid carrier, or both, and then, if necessary, shaping the product.
[0098] The compounds, when it is desirable to deliver them systemically, may be formulated for parenteral administration by injection, e.g., by bolus injection or continuous infusion. Formulations for injection may be presented in unit dosage form, e.g., in ampoules or in multi-dose containers, with an added preservative. The compositions may take such forms as suspensions, solutions or emulsions in oily or aqueous vehicles, and may contain formulatory agents such as suspending, stabilizing and/or dispersing agents.
[0099] Pharmaceutical formulations for parenteral administration include aqueous solutions of the active compounds in water-soluble form. Additionally, suspensions of the active compounds may be prepared as appropriate oily injection suspensions. Suitable lipophilic solvents or vehicles include fatty oils such as sesame oil, or synthetic fatty acid esters, such as ethyl oleate or triglycerides, or liposomes. Aqueous injection suspensions may contain substances which increase the viscosity of the suspension, such as sodium carboxymethyl cellulose, sorbitol, or dextran. Optionally, the suspension may also contain suitable stabilizers or agents which increase the solubility of the compounds to allow for the preparation of highly concentrated solutions.
[0100] Alternatively, the active compounds may be in powder form for constitution with a suitable vehicle (e.g., saline, buffer, or sterile pyrogen-free water) before use.
[0101] Compositions suitable for oral administration may be presented as discrete units, such as capsules, tablets, pills, lozenges, each containing a predetermined amount of the active compound (e.g., gelsolin). Other compositions include suspensions in aqueous liquids or non-aqueous liquids such as a syrup, elixir, an emulsion, or a gel.
[0102] Pharmaceutical preparations for oral use can be obtained as solid excipient, optionally grinding a resulting mixture, and processing the mixture of granules, after adding suitable auxiliaries, if desired, to obtain tablets or dragee cores. Suitable excipients are, in particular, fillers such as sugars, including lactose, sucrose, mannitol, sorbitol or cellulose preparations such as, for example, maize starch, wheat starch, rice starch, potato starch, gelatin, gum tragacanth, methyl cellulose, hydroxypropylmethyl-cellulose, sodium carboxymethylcellulose, and/or polyvinylpyrrolidone (PVP). If desired, disintegrating agents may be added, such as the cross-linked polyvinyl pyrrolidone, agar, or alginic acid or a salt thereof such as sodium alginate. Optionally the oral formulations may also be formulated in saline or buffers, i.e. EDTA for neutralizing internal acid conditions or may be administered without any carriers.
[0103] Also specifically contemplated are oral dosage forms of the above component or components. The component or components may be chemically modified so that oral delivery of the derivative is efficacious. Generally, the chemical modification contemplated is the attachment of at least one moiety to the component molecule itself, where said moiety permits (a) inhibition of proteolysis; and (b) uptake into the blood stream from the stomach or intestine. Also desired is the increase in overall stability of the component or components and increase in circulation time in the body. Examples of such moieties include: polyethylene glycol, copolymers of ethylene glycol and propylene glycol, carboxymethyl cellulose, dextran, polyvinyl alcohol, polyvinyl pyrrolidone and polyproline. Abuchowski and Davis, 1981, “Soluble Polymer-Enzyme Adducts” In: Enzymes as Drugs , Hocenberg and Roberts, eds., Wiley-Interscience, New York, N.Y., pp. 367-383; Newmark, et al., 1982, J. Appl. Biochem. 4:185-189. Other polymers that could be used are poly-1,3-dioxolane and poly-1,3,6-tioxocane. Preferred for pharmaceutical usage, as indicated above, are polyethylene glycol moieties.
[0104] For the component (or derivative) the location of release may be the stomach, the small intestine (the duodenum, the jejunum, or the ileum), or the large intestine. One skilled in the art has available formulations which will not dissolve in the stomach, yet will release the material in the duodenum or elsewhere in the intestine. Preferably, the release will avoid the deleterious effects of the stomach environment, either by protection of gelsolin or by release of the biologically active material beyond the stomach environment, such as in the intestine.
[0105] To ensure full gastric resistance a coating impermeable to at least pH 5.0 is essential. Examples of the more common inert ingredients that are used as enteric coatings are cellulose acetate trimellitate (CAT), hydroxypropylmethylcellulose phthalate (HPMCP), HPMCP 50, HPMCP 55, polyvinyl acetate phthalate (PVAP), Eudragit L30D, Aquateric, cellulose acetate phthalate (CAP), Eudragit L, Eudragit S, and Shellac. These coatings may be used as mixed films.
[0106] A coating or mixture of coatings can also be used on tablets, which are not intended for protection against the stomach. This can include sugar coatings, or coatings which make the tablet easier to swallow. Capsules may consist of a hard shell (such as gelatin) for delivery of dry therapeutic i.e. powder; for liquid forms, a soft gelatin shell may be used. The shell material of cachets could be thick starch or other edible paper. For pills, lozenges, molded tablets or tablet triturates, moist massing techniques can be used.
[0107] The therapeutic can be included in the formulation as fine multi-particulates in the form of granules or pellets of particle size about 1 mm. The formulation of the material for capsule administration could also be as a powder, lightly compressed plugs or even as tablets. The therapeutic could be prepared by compression.
[0108] Colorants and flavoring agents may all be included. For example, gelsolin may be formulated (such as by liposome or microsphere encapsulation) and then further contained within an edible product, such as a refrigerated beverage containing colorants and flavoring agents.
[0109] One may dilute or increase the volume of the therapeutic with an inert material. These diluents could include carbohydrates, especially mannitol, lactose, anhydrous lactose, cellulose, sucrose, modified dextrans and starch. Certain inorganic salts may be also be used as fillers including calcium triphosphate, magnesium carbonate and sodium chloride. Some commercially available diluents are Fast-Flo, Emdex, STA-Rx 1500, Emcompress and Avicell.
[0110] Disintegrants may be included in the formulation of the therapeutic into a solid dosage form. Materials used as disintegrants include but are not limited to starch, including the commercial disintegrant based on starch, Explotab. Sodium starch glycolate, Amberlite, sodium carboxymethylcellulose, ultramylopectin, sodium alginate, gelatin, orange peel, acid carboxymethyl cellulose, natural sponge and bentonite may all be used. Another form of the disintegrants are the insoluble cationic exchange resins. Powdered gums may be used as disintegrants and as binders and these can include powdered gums such as agar, Karaya or tragacanth. Alginic acid and its sodium salt are also useful as disintegrants.
[0111] Binders may be used to hold the therapeutic agent together to form a hard tablet and include materials from natural products such as acacia, tragacanth, starch and gelatin. Others include methyl cellulose (MC), ethyl cellulose (EC) and carboxymethyl cellulose (CMC). Polyvinyl pyrrolidone (PVP) and hydroxypropylmethyl cellulose (HPMC) could both be used in alcoholic solutions to granulate the therapeutic.
[0112] An anti-frictional agent may be included in the formulation of the therapeutic to prevent sticking during the formulation process. Lubricants may be used as a layer between the therapeutic and the die wall, and these can include but are not limited to; stearic acid including its magnesium and calcium salts, polytetrafluoroethylene (PTFE), liquid paraffin, vegetable oils and waxes. Soluble lubricants may also be used such as sodium lauryl sulfate, magnesium lauryl sulfate, polyethylene glycol of various molecular weights, Carbowax 4000 and 6000.
[0113] Glidants that might improve the flow properties of the drug during formulation and to aid rearrangement during compression might be added. The glidants may include starch, talc, pyrogenic silica and hydrated silicoaluminate.
[0114] To aid dissolution of the therapeutic into the aqueous environment a surfactant might be added as a wetting agent. Surfactants may include anionic detergents such as sodium lauryl sulfate, dioctyl sodium sulfosuccinate and dioctyl sodium sulfonate. Cationic detergents might be used and could include benzalkonium chloride or benzethomium chloride. The list of potential non-ionic detergents that could be included in the formulation as surfactants are lauromacrogol 400, polyoxyl 40 stearate, polyoxyethylene hydrogenated castor oil 10, 50 and 60, glycerol monostearate, polysorbate 40, 60, 65 and 80, sucrose fatty acid ester, methyl cellulose and carboxymethyl cellulose. These surfactants could be present in the formulation of gelsolin either alone or as a mixture in different ratios.
[0115] Pharmaceutical preparations which can be used orally include push-fit capsules made of gelatin, as well as soft, sealed capsules made of gelatin and a plasticizer, such as glycerol or sorbitol. The push-fit capsules can contain the active ingredients in admixture with filler such as lactose, binders such as starches, and/or lubricants such as talc or magnesium stearate and, optionally, stabilizers. In soft capsules, the active compounds may be dissolved or suspended in suitable liquids, such as fatty oils, liquid paraffin, or liquid polyethylene glycols. In addition, stabilizers may be added.
[0116] Microspheres formulated for oral administration may also be used. Such microspheres have been well defined in the art. All formulations for oral administration should be in dosages suitable for such administration.
[0117] For buccal administration, the compositions may take the form of tablets or lozenges formulated in conventional manner.
[0118] For administration by inhalation, the compounds for use according to the present invention may be conveniently delivered in the form of an aerosol spray presentation from pressurized packs or a nebulizer, with the use of a suitable propellant, e.g., dichlorodifluoromethane, trichlorofluoromethane, dichlorotetrafluoroethane, carbon dioxide or other suitable gas. In the case of a pressurized aerosol the dosage unit may be determined by providing a valve to deliver a metered amount. Capsules and cartridges of e.g. gelatin for use in an inhaler or insufflator may be formulated containing a powder mix of the compound and a suitable powder base such as lactose or starch.
[0119] Also contemplated herein is pulmonary delivery of gelsolin. Gelsolin is delivered to the lungs of a mammal while inhaling and traverses across the lung epithelial lining to the blood stream. Other reports of inhaled molecules include Adjei et al., 1990, Pharmaceutical Research, 7:565-569; Adjei et al., 1990, International Journal of Pharmaceutics, 63:135-144 (leuprolide acetate); Braquet et al., 1989, Journal of Cardiovascular Pharmacology, 13 (suppl. 5):143-146 (endothelin-1); Hubbard et al., 1989, Annals of Internal Medicine, Vol. III, pp. 206-212 (a1-antitrypsin); Smith et al., 1989, J. Clin. Invest. 84:1145-1146 (a-1-proteinase); Oswein et al., 1990, “Aerosolization of Proteins”, Proceedings of Symposium on Respiratory Drug Delivery II, Keystone, Colo., March, (recombinant human growth hormone); Debs et al., 1988, J. Immunol. 140:3482-3488 (interferon-γ and tumor necrosis factor alpha) and Platz et al., U.S. Pat. No. 5,284,656 (granulocyte colony stimulating factor). A method and composition for pulmonary delivery of drugs for systemic effect is described in U.S. Pat. No. 5,451,569, issued Sep. 19, 1995 to Wong et al.
[0120] Contemplated for use in the practice of this invention are a wide range of mechanical devices designed for pulmonary delivery of therapeutic products; including but not limited to nebulizers, metered dose inhalers, and powder inhalers, all of which are familiar to those skilled in the art.
[0121] Some specific examples of commercially available devices suitable for the practice of this invention are the Ultravent nebulizer, manufactured by Mallinckrodt, Inc., St. Louis, Mo.; the Acorn II nebulizer, manufactured by Marquest Medical Products, Englewood, Colo.; the Ventolin metered dose inhaler, manufactured by Glaxo Inc., Research Triangle Park, N.C.; and the Spinhaler powder inhaler, manufactured by Fisons Corp., Bedford, Mass.
[0122] All such devices require the use of formulations suitable for the dispensing of gelsolin. Typically, each formulation is specific to the type of device employed and may involve the use of an appropriate propellant material, in addition to the usual diluents, adjuvants and/or carriers useful in therapy. Also, the use of liposomes, microcapsules or microspheres, inclusion complexes, or other types of carriers is contemplated. Chemically modified gelsolin may also be prepared in different formulations depending on the type of chemical modification or the type of device employed.
[0123] Formulations suitable for use with a nebulizer, either jet or ultrasonic, will typically comprise gelsolin dissolved in water at a concentration of about 0.1 to 25 mg of biologically active gelsolin per mL of solution. The formulation may also include a buffer and a simple sugar (e.g., for gelsolin stabilization and regulation of osmotic pressure). The nebulizer formulation may also contain a surfactant, to reduce or prevent surface induced aggregation of the gelsolin caused by atomization of the solution in forming the aerosol.
[0124] Formulations for use with a metered-dose inhaler device will generally comprise a finely divided powder containing the gelsolin suspended in a propellant with the aid of a surfactant. The propellant may be any conventional material employed for this purpose, such as a chlorofluorocarbon, a hydrochlorofluorocarbon, a hydrofluorocarbon, or a hydrocarbon, including trichlorofluoromethane, dichlorodifluoromethane, dichlorotetrafluoroethanol, and 1,1,1,2-tetrafluoroethane, or combinations thereof. Suitable surfactants include sorbitan trioleate and soya lecithin. Oleic acid may also be useful as a surfactant.
[0125] Formulations for dispensing from a powder inhaler device will comprise a finely divided dry powder containing gelsolin and may also include a bulking agent, such as lactose, sorbitol, sucrose, or mannitol in amounts which facilitate dispersal of the powder from the device, e.g., 50 to 90% by weight of the formulation. The gelsolin should most advantageously be prepared in particulate form with an average particle size of less than 10 min (or microns), most preferably 0.5 to 5 mm, for most effective delivery to the distal lung.
[0126] Nasal (or intranasal) delivery of a pharmaceutical composition of the present invention is also contemplated. Nasal delivery allows the passage of a pharmaceutical composition of the present invention to the blood stream directly after administering the therapeutic product to the nose, without the necessity for deposition of the product in the lung. Formulations for nasal delivery include those with dextran or cyclodextran.
[0127] For nasal administration, a useful device is a small, hard bottle to which a metered dose sprayer is attached. In one embodiment, the metered dose is delivered by drawing the pharmaceutical composition of the present invention solution into a chamber of defined volume, which chamber has an aperture dimensioned to aerosolize and aerosol formulation by forming a spray when a liquid in the chamber is compressed. The chamber is compressed to administer the pharmaceutical composition of the present invention. In a specific embodiment, the chamber is a piston arrangement. Such devices are commercially available.
[0128] Alternatively, a plastic squeeze bottle with an aperture or opening dimensioned to aerosolize an aerosol formulation by forming a spray when squeezed is used. The opening is usually found in the top of the bottle, and the top is generally tapered to partially fit in the nasal passages for efficient administration of the aerosol formulation. Preferably, the nasal inhaler will provide a metered amount of the aerosol formulation, for administration of a measured dose of the drag.
[0129] The compounds may also be formulated in rectal or vaginal compositions such as suppositories or retention enemas, e.g., containing conventional suppository bases such as cocoa butter or other glycerides.
[0130] In addition to the formulations described previously, the compounds may also be formulated as a depot preparation. Such long acting formulations may be formulated with suitable polymeric or hydrophobic materials (for example as an emulsion in an acceptable oil) or ion exchange resins, or as sparingly soluble derivatives, for example, as a sparingly soluble salt.
[0131] The pharmaceutical compositions also may comprise suitable solid or gel phase carriers or excipients. Examples of such carriers or excipients include but are not limited to calcium carbonate, calcium phosphate, various sugars, starches, cellulose derivatives, gelatin, and polymers such as polyethylene glycols.
[0132] Suitable liquid or solid pharmaceutical preparation forms are, for example, aqueous or saline solutions for inhalation, microencapsulated, encochleated, coated onto microscopic gold particles, contained in liposomes, nebulized, aerosols, pellets for implantation into the skin, or dried onto a sharp object to be scratched into the skin. The pharmaceutical compositions also include granules, powders, tablets, coated tablets, (micro)capsules, suppositories, syrups, emulsions, suspensions, creams, drops or preparations with protracted release of active compounds, in whose preparation excipients and additives and/or auxiliaries such as disintegrants, binders, coating agents, swelling agents, lubricants, flavorings, sweeteners or solubilizers are customarily used as described above. The pharmaceutical compositions are suitable for use in a variety of drug delivery systems. For a brief review of methods for drug delivery, see Langer, Science 249:1527-1533, 1990, which is incorporated herein by reference.
[0133] The therapeutic agent(s), including specifically but not limited to gelsolin, may be provided in particles. Particles as used herein means nano or microparticles (or in some instances larger) which can consist in whole or in part of gelsolin or the other therapeutic agent(s) as described herein. The particles may contain the therapeutic agent(s) in a core surrounded by a coating, including, but not limited to, an enteric coating. The therapeutic agent(s) also may be dispersed throughout the particles. The therapeutic agent(s) also may be adsorbed into the particles. The particles may be of any order release kinetics, including zero order release, first order release, second order release, delayed release, sustained release, immediate release, and any combination thereof, etc. The particle may include, in addition to the therapeutic agent(s), any of those materials routinely used in the art of pharmacy and medicine, including, but not limited to, erodible, nonerodible, biodegradable, or nonbiodegradable material or combinations thereof. The particles may be microcapsules which contain the gelsolin in a solution or in a semi-solid state. The particles may be of virtually any shape.
[0134] Both non-biodegradable and biodegradable polymeric materials can be used in the manufacture of particles for delivering the therapeutic agent(s). Such polymers may be natural or synthetic polymers. The polymer is selected based on the period of time over which release is desired. Bioadhesive polymers of particular interest include bioerodible hydrogels described by H. S. Sawhney, C. P. Pathak and J. A. Hubell in Macromolecules , (1993) 26:581-587, the teachings of which are incorporated herein. These include polyhyaluronic acids, casein, gelatin, glutin, polyanhydrides, polyacrylic acid, alginate, chitosan, poly(methyl methacrylates), poly(ethyl methacrylates), poly(butylmethacrylate), poly(isobutyl methacrylate), poly(hexylmethacrylate), poly(isodecyl methacrylate), poly(lauryl methacrylate), poly(phenyl methacrylate), poly(methyl acrylate), poly(isopropyl acrylate), poly(isobutyl acrylate), and poly(octadecyl acrylate).
[0135] The therapeutic agent(s) may be contained in controlled release systems. The term “controlled release” is intended to refer to any drug-containing formulation in which the manner and profile of drug release from the formulation are controlled. This refers to immediate as well as non-immediate release formulations, with non-immediate release formulations including but not limited to sustained release and delayed release formulations. The term “sustained release” (also referred to as “extended release”) is used in its conventional sense to refer to a drug formulation that provides for gradual release of a drug over an extended period of time, and that preferably, although not necessarily, results in substantially constant blood levels of a drug over an extended time period. The term “delayed release” is used in its conventional sense to refer to a drug formulation in which there is a time delay between administration of the formulation and the release of the drug therefrom. “Delayed release” may or may not involve gradual release of drug over an extended period of time, and thus may or may not be “sustained release.”
[0136] Use of a long-term sustained release implant may be particularly suitable for treatment of chronic conditions. “Long-term” release, as used herein, means that the implant is constructed and arranged to deliver therapeutic levels of the active ingredient for at least 7 days, and preferably 30-60 days. Long-term sustained release implants are well-known to those of ordinary skill in the art and include some of the release systems described above.
[0137] For topical administration to the eye, nasal membranes, mucous membranes or to the skin, the gelsolin may be formulated as ointments, creams or lotions, or as a transdermal patch or intraocular insert or iontophoresis. For example, ointments and creams can be formulated with an aqueous or oily base alone or together with suitable thickening and/or gelling agents. Lotions can be formulated with an aqueous or oily base and, typically, further include one or more emulsifying agents, stabilizing agents, dispersing agents, suspending agents, thickening agents, or coloring agents. (See, e.g., U.S. Pat. No. 5,563,153, entitled “Sterile Topical Anesthetic Gel”, issued to Mueller, D., et al., for a description of a pharmaceutically acceptable gel-based topical carrier.)
[0138] In general, the gelsolin is present in a topical formulation in an amount ranging from about 0.01% to about 30.0% by weight, based upon the total weight of the composition. Preferably, the gelsolin is present in an amount ranging from about 0.5 to about 30% by weight and, most preferably, the gelsolin is present in an amount ranging from about 0.5 to about 10% by weight. In one embodiment, the compositions of the invention comprise a gel mixture to maximize contact with the surface of the localized pain and minimize the volume and dosage necessary to alleviate the localized pain. GELFOAM® (a methylcellulose-based gel manufactured by Upjohn Corporation) is a preferred pharmaceutically acceptable topical carrier. Other pharmaceutically acceptable carriers include iontophoresis for transdermal drug delivery.
[0139] The invention also contemplates the use of kits. In some aspects of the invention, the kit can include a pharmaceutical preparation vial, a pharmaceutical preparation diluent vial, and gelsolin. The vial containing the diluent for the pharmaceutical preparation is optional. The diluent vial contains a diluent such as physiological saline for diluting what could be a concentrated solution or lyophilized powder of gelsolin. The instructions can include instructions for mixing a particular amount of the diluent with a particular amount of the concentrated pharmaceutical preparation, whereby a final formulation for injection or infusion is prepared. The instructions may include instructions for treating a subject with an effective amount of gelsolin. It also will be understood that the containers containing the preparations, whether the container is a bottle, a vial with a septum, an ampoule with a septum, an infusion bag, and the like, can contain indicia such as conventional markings which change color when the preparation has been autoclaved or otherwise sterilized.
[0140] The present invention is further illustrated by the following Examples, which in no way should be construed as further limiting. The entire contents of all of the references (including literature references, issued patents, published patent applications, and co-pending patent applications) cited throughout this application are hereby expressly incorporated by reference.
EXAMPLES
[0141] Plasma gelsolin (pGSN) is a secreted protein that circulates in the extracellular fluids of humans at concentrations averaging 250 mg/l. Diverse types of tissue injury lead to prolonged reductions in plasma gelsolin levels. Following severe tissue injury encountered in severe trauma, burns, sepsis, major surgery and hematopoietic stem cell transplant patients, declines in gelsolin (GSN) levels to approximately less than 25% of normal precede and, therefore, predict critical care complications measured by assisted ventilation requirements, length of intensive care unit residence and overall hospital stays, death and specific sequelae such as secondary lung injury (e.g. adult respiratory distress syndrome (ARDS), acute lung injury (ALI), multiple organ dysfunction syndromes (MODS)). Similar plasma gelsolin reductions in animal models precede lung permeability changes and inflammation, and infusion of recombinant plasma gelsolin ameliorates these effects.
Example 1
Plasma gelsolin (pGSN) Concentration is Decreased in Patients with Rheumatoid Arthritis (RA) Compared to Healthy Controls and Lower in Synovial Fluid than in Blood in Patients with RA
[0142] We measured plasma gelsolin (pGSN) levels in patients with rheumatoid arthritis (RA) to experimentally test the hypothesis that plasma gelsolin levels fall in response to the initial (unknown) injury inflicted by the agency causing rheumatoid arthritis. As shown in FIG. 1 , circulating (pGSN) levels were significantly lower in patients with RA compared to matched healthy controls (103±23 versus 142±29, P=0.0002, FIG. 1 ). pGSN levels were similar in both male and females, and were not dependent on the age of the patients or on the duration of arthritis. Circulating pGSN levels were inversely correlated to the levels of C-reactive protein (1=-0.272, p=0.026).
Materials and Methods:
[0143] Patients: Plasma and synovial fluid samples were collected from 82 RA patients attending the Rheumatology clinics, at Sahlgrenska University Hospital in Gothenburg, for acute joint effusion. RA was diagnosed according to the American College of Rheumatology criteria. At the time of synovial fluid and blood sampling all the patients received non-steroidal anti-inflammatory drugs. Recent radiographs of the hands and feet were obtained for all the patients. Presence of bone erosions defined as the loss of cortical definition of the joint, was recorded in proximal interphalangeal, metacarpophalangeal, carpus, interphalangeal and metatarsophalangeal joints of forefeet. Presence of one erosion was sufficient to fulfil requirement of an erosive disease. Presence of rheumatoid factor of any of immunoglobulin isotypes tested (IgM, -A, -G) was considered as positive. Control blood samples (n=87) were obtained from the blood donors attending Blood Transfusion Unit of Sahlgrenska University Hospital and matching the RA patients for age and gender.
[0144] Collection and preparation of samples: Synovial fluid was obtained from knee joints by arthrocentesis, aseptically aspirated and transferred into sodium citrate (0.129 mol/l; pH 7.4) containing tubes. Blood samples were simultaneously obtained from the cubital vein and collected into sodium citrate medium. Collected blood and synovial fluid samples were centrifuged at 800 g for 15 minutes, aliquoted, and stored frozen at −70° C. until use.
[0145] Measurement of pGSN concentration in plasma and synovial fluid by pyrene actin-nucleation assay: pGSN is activated by calcium and binds two actin monomers to form a nucleus from which actin polymerizes in pointed (slowest growing) end direction. Pyrene actin was prepared by derivatizing actin with N-pyrenyliodoacetamide (Molecular Probes, Eugene Oreg.). Before use pyrene actin was diluted in depolymerization buffer (Buffer A: 0.5 mM ATP, 5 mM β-mercaptoethanol, 0.2 mM Tris, 0.2 mM CaCl 2 , pH 7.4) to 20 μM, stored 1 h at 37° C. to reach monomer equilibrium and centrifuged at 250,000 g, 4° C. for 30 minutes, in an Optima™ TL Ultracentrifuge (Beckman) to pellet any remnant filamentous actin. The supernatant was withdrawn and stored in an ice water bath until used. Platelet poor plasma to be analyzed was diluted 1:5 in buffer B (0.1 M KCl, 0.2 mM MgCl 2 , 0.2 mM CaCl 2 , 0.5 mM ATP, 10 mM Tris, 0.5 mM mercaptoethanol, pH 7.4). Pyrene actin fluorescence was recorded using a luminescence fluorometer (FluoroMax-2®, JobinYvon-Spex Instruments S.A., Inc). Excitation and emission wavelengths were 366 and 386 nm, respectively. Pyrene actin was added to a final concentration of 1 μM in 280 μl buffer B containing 0.4 μM phalloidin, 1.5 mM CaCl 2 and 5 μl of diluted sample in 6×50 mm borosilicate glass culture tubes (Kimble). Nucleation was monitored over 240 s in the fluorometer following a fast vortex. The linear slope of the fluorescence increase was calculated between 100-200 s. All the samples were run in duplicates. Polymerization rate in each sample was converted to pGSN concentration by use of a standard curve of recombinant human pGSN.
[0146] Statistics: The level of pGSN in the blood and synovial fluid samples were expressed as mean±SD. Comparison between the matched blood and synovial fluid samples were analyzed by the paired t-test. Comparison of pGSN levels was also performed between the patient blood samples and the healthy controls. For further comparison patient material was stratified according to radiological findings (erosive RA vs. non-erosive RA). Differences in pGSN levels in the blood and synovial fluid between the groups were calculated separately employing the Mann-Whitney U test. For the evaluation of possible influence of the ongoing treatment on the pGSN levels, patient material was stratified according to DMARD treatment (treated vs. untreated). Comparison between the groups was performed using the Mann-Whitney U test. For all the statistical evaluation of the results, P-values below 0.05 were considered statistically significant.
Example 2
The Gelsolin Isoform Present in Synovial Fluid (SF) of RA Patients is the Plasma Isoform of Gelsolin (pGSN)
[0147] Since gelsolin is produced as both an intracellular and extracellular isoform, each of which have the capacity to induce actin polymerization, we analyzed the origin of the gelsolin activity by immunoblotting with an antibody specific for the plasma isoform (α-pGSN). Gelsolin present in SF is composed mainly of the plasma isoform ( FIG. 2 ). Plasma origin of gelsolin was also supported by a correlation between gelsolin levels in plasma and synovial fluid in the matched pair of samples (r=0.39, p=0.0006). However, pGSN activity in the SF samples from RA patients were significantly lower than that of plasma (pg/ml, 69±18 vs. 103±23, p=0.04) indicating local consumption.
Materials and Methods
[0148] Immunoblotting: The platelet poor plasmas or synovial fluids were diluted 1:100 in 1× sample buffer (SB, 20% glycerol, 4.6% Tris, 0.25 M Tris-HCl, 0.01% Bromphenol blue, 10% v/v 2-Mercaptoethanol, pH 6.8) for test of gelsolin isoform, vortexed briefly and boiled at 100° C. for 10 minutes. Samples (10 μl) were run on 10% SDS-PAGE (sodium dodecylsulfate polyacrylamide gelelectrophoresis) gels in a modified Laemmli system. Platelet lysate (2×10̂8/ml, 5 μl) and human recombinant pGSN were run as negative and positive controls for pGSN respectively. Proteins were separated for 1.5 hour at 120V. Immobilon P membranes (PVDF, 0.45 μm; Millipore Corp., Bedford, Mass.) were soaked in methanol for 1 minute and transfer buffer (192 mM glycine, 25 mM Tris, 0.1% Sodium Dodecyl Sulfate, 20% Methanol) for 5 minutes, before transfer. The transfer was carried out at variable voltage, 1A for 90 minutes. The membranes were blocked overnight in PBS containing 0.05% Tween-20, 5% Carnation nonfat dry milk and 0.05% sodium azide pH 7.4 at 4° C. For pGSN a polyclonal antibody specific for the human plasma isoform was used (1:2000, 2 h, produced in the lab). For all isoforms of GSN a primary monoclonal 2c4 anti-gelsolin antibody was used (1:2500, 2 h, produced in the lab). Secondary antibodies used were rabbit-anti-mouse IgG (H+ L)-HRP (1:5000, 80 min) and goat-anti-mouse IgG (H+L)-HRP conjugate respectively (1:3300, 80 min, Bio-Rad, Hercules, Calif.). Membranes were washed 3 times in PBS containing 0.05% Tween-20 between incubations.
[0149] Chemiluminescence detection was done using SuperSignal®, West Pico Chemiluminescent Substrate for detection of HRP (PIERCE, Rockford, Ill.). The membranes were exposed to 2 ml each of SuperSignal® West Pico Stable Peroxide Solution and SuperSignal® West Pico Luminol/Enhancer Solution for 2 minutes. HyBlot CL autoradiography film (Denville Scientific, Inc., Metuchen, N.J.) was exposed to the membrane for 1 minute in a FBXC 810 autoradiography cassette (FischerBiotech, Pittsburgh, Pa.). The film was developed using a M35A X-OMAT Processor (Kodak).
Example 3
pGSN is Decreased at Early Stages of an Experimental Mouse Model of Septic Arthritis/Sepsis
[0150] Levels of circulating pGSN were decreased both during streptococcal and staphylococcal infection. This decrease occurred early during the time course of disease, beginning 2 days post-bacterial inoculation both in arthritic and septic groups of animals. Prior to injection (day 0), the average pGSN level of the mice was 200±20 mg/L. By day 2 pGSN levels decreased to 138±16 mg/L for the arthritic Staphylococcus aureus ( S. aureus ) treated (7×10̂6 cfu/mouse) animals, 157±15 mg/L for the septic S. aureus injected animals (3.5×10̂7 cfu/mouse), and 152±15 mg/L for the animals injected with Streptococcus agalactiae (Str. agalactiae) (1×10̂7 cfu/mouse). The pGSN levels at day 9 were 141 t 21, 151±15, and 124±13 mg/L, respectively. Only the animals injected with streptococcal bacteria displayed further decrease of the circulating pGSN levels at day 9. pGSN decrease was not related to the intensity of the infection since pGSN concentrations following administration of septic doses (5 times higher than the arthritic ones), which result in higher mortality, were not lower than those observed in the arthritic-dosed mice.
Materials and Methods
[0151] Induction of S. aureus arthritis and sepsis: Female 5-6 weeks old NMRI mice were purchased from ALAB (Stockholm, Sweden) and maintained in the animal facility of the Department of Rheumatology, University of Goteborg. They were housed 10-11 animals per cage under standard conditions of temperature and light and fed standard laboratory chow and water ad libitum. S. aureus , strain LS-1, originally isolated from a swollen joint of a spontaneously arthritic NZBxW mouse, strain Newman, as well as Str. agalactiae strain 6313, a clinical isolate belonging to serotype III, were used for the induction of septic. arthritis and sepsis. Bacteria were kept frozen at −20° C., in PBS (0.13 M sodium chloride, 10 mM sodium phosphate, pH 7,4), containing 5% BSA and 10% dimethyl sulfoxide, until used. Before the injection, the bacterial solution was thawed, washed twice with PBS, and adjusted with PBS to the desired concentration. Mice were injected into the tail vein with a suspension of S. aureus or Str. agalactiae in 0.2 ml PBS. Viable counts in the leftover solution were determined to check the exact number of bacteria injected and presented as colony forming units (cfu/ml).
[0152] All the mice were monitored individually during the observation period of 8-9 days by assessment of joint appearance, weight, general appearance, alertness, and skin abnormalities. Blood samples were obtained from the tail vein in a sterile tube without anticoagulant and remained to clot for 6-8 hours. The samples were centrifuged at 3000×g for 15 min, serum was aliquoted and kept frozen at −70° C. until used.
[0153] Experimental protocol: twenty mice obtained intravenously (i.v.) a septic (LS-1, 4×10 7 cfu/mouse, n=10) or arthritogenic (7×10 6 cfu/mouse, n=10) dose of S. aureus . Additional 10 mice obtained intravenously a septic dose of Str. agalactiae (1×10 7 cfu/mouse). On days—3, 2, 4, 6, and 9 blood samples were collected by the tail vein incision for the determination pGSN levels. On day 9 all mice were sacrificed by cervical dislocation. pGSN level was determined with the same method as for the human samples (pyrene actin nucleation assay).
Example 4
pGSN Supplementation to Mice Delays Development of Arthritis
[0154] Supplementation of mice with recombinant gelsolin was performed over 7 days with 24 h interval starting immediately before bacterial inoculation (4×10 7 /ml). Five mice received gelsolin while 7 mice received PBS and were used as controls. During the first 9 days of staphylococcal infection no difference was observed in gelsolin-treated and the control groups with respect to weight loss, survival rate or development of arthritis. However, fewer of the gelsolin-treated mice developed arthritis on day 3 (1 treated vs 4 non-treated—See Table 1).
[0000]
TABLE 1
Dynamics of weight, survival and development of arthritis
in NMRI mice infected intravenously with S. aureus .
Day 1
Day 3
Day 5
Day 7
Day 9
Day 28
Gel-
31.5 g
30.0 g
27.2 g
25.3 g
25.7 g
30.8 g
Mean
solin
weight
PBS
31.2
28.5
27.7
22.9
25.4
32.4
Mean
con-
weight
trols
5G/7C
5G/7C
5G/7C
5G/7C
3G/6C
2G/6C
Survival
1G/0C
1G/4C
2G/4C
3G/4C
2G/1C
2G/2C
Arthritis
G = plasma gelsolin, C = Control.
Materials and Methods
[0155] Twelve mice were injected intravenously (i.v.) with a septic dose of S. aureus (Newman, 4×10 7 cfu/mouse). Five mice received recombinant human pGSN intra-peritoneally (i.p.) during days 0-7 and the remaining 7 mice received PBS. The mice were monitored individually up to day 28 and signs of arthritis, weight, general appearance, and alertness were followed.
[0156] Recombinant pGSN was produced in E. coli , refolded with GSSG, formulated in 0.1 M NaCl and 1 mM CaCl 2 by Biogen-Idec, Inc. (Cambridge, Mass.) and kept at −70° C. prior to use. Mice were injected with recombinant pGSN i.p. (6 mg/mouse) one hour prior to the bacterial challenge and continued with 24-hours interval (3 mg/mouse) during 7 days. The controls received a corresponding volume of PBS.
Example 5
[0157] The hypothesis that administration of gelsolin could impact upon the inflammatory processes is tested in a rodent model of collagen induced arthritis (CIA), an autoimmune model that resembles rheumatoid arthritis. CIA is inducible in inbred DBA/1 male mice by priming intradermally with heterologous or homologous collagen II (about 50 microgram) in Freunds complete adjuvant and 2 weeks later boosting with the same amount of collagen II in Freunds incomplete adjuvant. The arthritis develops approximately 3 weeks after the priming dose and reaches its maximum within 8 weeks post priming. The mice have high levels of collagen II specific antibodies, collagen II specific T cells as well as signs of systemic inflammation (e.g. production of IL-6, TNF etc). Locally in the joints one observes both overwhelming inflammatory infiltrates (consisting of T cells, macrophages, neutrophils and fibroblasts) as well as severe destruction of cartilage and subchondral bone. These features mimic well the process seen in human rheumatoid arthritis (Myers et al., Life Sciences 61, p 1861-1878, 1997).
[0158] In a therapeutic test one set of test animals receives, for example, subcutaneously 8 mg of bovine serum albumin or 8 mg human recombinant plasma gelsolin once on day ten from the start of therapy (1×) or three doses on days 2, 5 and 10 (3×). This route of administration and dosing has previously been shown to raise gelsolin levels depleted 50% by sepsis to normal. Several parameters of the disease (e.g., clinical signs and symptoms, onset, progression, severity, and remission of symptoms) are measured.
[0159] In summary, our findings support the two aspects of the hypothesis posed, namely, that reductions in plasma gelsolin levels precede manifestations of inflammatory diseases such as rheumatoid arthritis and that systemic treatment with plasma gelsolin prevents and/or suppresses these manifestations. One clinical correlate of these observations is that serial monitoring of plasma gelsolin levels could become part of the management strategy of inflammatory diseases such as rheumatoid arthritis, flagging when to intensify therapy. Another correlate is that prophylactic elevation of plasma gelsolin levels might protect patients from the sequelae of inflammation.
[0160] Although not intending to be bound by any particular mechanism or theory, it is presumed that plasma gelsolin is depleted from the blood during inflammatory diseases (such as rheumatoid arthritis (RA)) and is localized or sequestered at the site of injury/inflammation (the joint space in rheumatoid arthritis). It is believed that plasma gelsolin functions at the site of inflammation by binding to inflammatory mediators and prevents them from causing further damage by inhibiting their actions on cellular receptors. This is supported by the fact that plasma gelsolin in vitro binds to some inflammatory mediators such as lysophosphatidic acid (LPA), Aβ (Alzheimer) peptide, diadenosine 5′,5′″-P1,P3-triphosphate (Ap3A), fibronectin, fibrinogen and lipopolysaccharide (LPS) and decreases certain cellular responses to platelet activating factor (PAF). Additionally, damaged cells at the inflamed joint release actin and gelsolin binds to actin. Gelsolin may have a protective role by severing filamentous actin that might otherwise be toxic. We believe that gelsolin has an anti-inflammatory effect, but when the inflammation is severe and prolonged as in RA, gelsolin supplementation might be beneficial in reducing or treating the inflammation. Sequestration or recruitment of gelsolin to the site of inflammation (such as the joint space in rheumatoid arthritis) could explain why the plasma levels are reduced although other explanations are also possible.
EQUIVALENTS
[0161] The foregoing written specification is considered to be sufficient to enable one ordinarily skilled in the art to practice the invention. The present invention is not to be limited in scope by the example(s) provided, since the example(s) are intended as mere illustrations of one or more aspects of the invention. Other functionally equivalent embodiments are considered within the scope of the invention. Various modifications of the invention in addition to those shown and described herein will become apparent to those skilled in the art from the foregoing description. Each of the limitations of the invention can encompass various embodiments of the invention. It is, therefore, anticipated that each of the limitations of the invention involving any one element or combinations of elements can be included in each aspect of the invention. This invention is not limited in its application to the details of construction and the arrangement of components set forth or illustrated in the drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways.
[0162] Also, the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having,” “containing”, “involving”, and variations thereof herein, is meant to encompass the items listed thereafter and equivalents thereof as well as additional items.
[0163] All references, patents and patent applications that are recited in this application are incorporated by reference herein in their entirety. | The invention relates to the use of gelsolin to treat inflammatory diseases (e.g., rheumatoid arthritis) and to the use of gelsolin to diagnose, monitor, and evaluate therapies of inflammatory diseases (e.g., rheumatoid arthritis). | 6 |
[0001] This application claims priority from U.S. Provisional Application No. 61/120,442, filed Dec. 6, 2008, the contents of which are hereby incorporated by reference in their entirety.
TECHNICAL FIELD
[0002] The present invention relates to optionally substituted 3-(thio, sulfinyl or sulfonyl)-7,8-dihydro-(1H or 2H)-imidazo[1,2-a]pyrazolo[4,3-e]pyrimidin-4(5H)-one or a substituted 3-(thio, sulfinyl or sulfonyl)-7,8,9-trihydro-(1H or 2H)-pyrimido[1,2-a]pyrazolo[4,3-e]pyrimidin-4(5H)-one compounds, e.g., compounds of Formula I as described below, processes for their production, their use as pharmaceuticals and pharmaceutical compositions comprising them. Of particular interest are novel compounds useful as inhibitors of phosphodiesterase 1 (PDE1), e.g., in the treatment of diseases involving disorders of the dopamine D1 receptor intracellular pathway, such as Parkinson's disease, depression, narcolepsy, damage to cognitive function, e.g., in schizophrenia, or disorders that may be ameliorated through enhanced progesterone-signaling pathway, e.g., female sexual dysfunction.
BACKGROUND OF THE INVENTION
[0003] Eleven families of phosphodiesterases (PDEs) have been identified but only PDEs in Family I, the Ca 2+ -calmodulin-dependent phosphodiesterases (CaM-PDEs), have been shown to mediate both the calcium and cyclic nucleotide (e.g. cAMP and cGMP) signaling pathways. The three known CaM-PDE genes, PDE1A, PDE1B, and PDE1C, are all expressed in central nervous system tissue. PDE is expressed throughout the brain with higher levels of expression in the CA1 to CA3 layers of the hippocampus and cerebellum and at a low level in the striatum. PDE1A is also expressed in the lung and heart. PDE1B is predominately expressed in the striatum, dentate gyrus, olfactory tract and cerebellum, and its expression correlates with brain regions having high levels of dopaminergic innervation. Although PDE1B is primarily expressed in the central nervous system, it may be detected in the heart. PDE1C is primarily expressed in olfactory epithelium, cerebellar granule cells, and striatum. PDE1C is also expressed in the heart and vascular smooth muscle.
[0004] Cyclic nucleotide phosphodiesterases decrease intracellular cAMP and cGMP signaling by hydrolyzing these cyclic nucleotides to their respective inactive 5′-monophosphates (5′AMP and 5′GMP). CaM-PDEs play a critical role in mediating signal transduction in brain cells, particularly within an area of the brain known as the basal ganglia or striatum. For example, NMDA-type glutamate receptor activation and/or dopamine D2 receptor activation result in increased intracellular calcium concentrations, leading to activation of effectors such as calmodulin-dependent kinase II (CaMKII) and calcineurin and to activation of CaM-PDEs, resulting in reduced cAMP and cGMP. Dopamine D1 receptor activation, on the other hand, leads to activation of nucleotide cyclases, resulting in increased cAMP and cGMP. These cyclic nucleotides in turn activate protein kinase A (PKA; cAMP-dependent protein kinase) and/or protein kinase G (PKG; cGMP-dependent protein kinase) that phosphorylate downstream signal transduction pathway elements such as DARPP-32 (dopamine and cAMP-regulated phosphoprotein) and cAMP responsive element binding protein (CREB). Phosphorylated DARPP-32 in turn inhibits the activity of protein phosphates-1 (PP-1), thereby increasing the state of phosphorylation of substrate proteins such as progesterone receptor (PR), leading to induction of physiologic responses. Studies in rodents have suggested that inducing cAMP and cGMP synthesis through activation of dopamine D1 or progesterone receptor enhances progesterone signaling associated with various physiological responses, including the lordosis response associated with receptivity to mating in some rodents. See Mani, et al., Science (2000) 287: 1053, the contents of which are incorporated herein by reference.
[0005] CaM-PDEs can therefore affect dopamine-regulated and other intracellular signaling pathways in the basal ganglia (striatum), including but not limited to nitric oxide, noradrenergic, neurotensin, CCK, VIP, serotonin, glutamate (e.g., NMDA receptor, AMPA receptor), GABA, acetylcholine, adenosine (e.g., A2A receptor), cannabinoid receptor, natriuretic peptide (e.g., ANP, BNP, CNP), DARPP-32, and endorphin intracellular signaling pathways.
[0006] Phosphodiesterase (PDE) activity, in particular, phosphodiesterase 1 (PDE1) activity, functions in brain tissue as a regulator of locomotor activity and learning and memory. PDE1 is a therapeutic target for regulation of intracellular signaling pathways, preferably in the nervous system, including but not limited to a dopamine D1 receptor, dopamine D2 receptor, nitric oxide, noradrenergic, neurotensin, CCK, VIP, serotonin, glutamate (e.g., NMDA receptor, AMPA receptor), GABA, acetylcholine, adenosine (e.g., A2A receptor), cannabinoid receptor, natriuretic peptide (e.g., ANP, BNP, CNP), endorphin intracellular signaling pathway and progesterone signaling pathway. For example, inhibition of PDE should act to potentiate the effect of a dopamine D1 agonist by protecting cGMP and cAMP from degradation, and should similarly inhibit dopamine D2 receptor signaling pathways, by inhibiting PDE1 activity. Chronic elevation in intracellular calcium levels is linked to cell death in numerous disorders, particularly in neurodegerative diseases such as Alzheimer's, Parkinson's and Huntington's Diseases and in disorders of the circulatory system leading to stroke and myocardial infarction. PDE1 inhibitors are therefore potentially useful in diseases characterized by reduced dopamine D1 receptor signaling activity, such as Parkinson's disease, restless leg syndrome, depression, narcolepsy and cognitive impairment. PDE1 inhibitors are also useful in diseases that may be alleviated by the enhancement of progesterone-signaling such as female sexual dysfunction.
[0007] There is thus a need for compounds that selectively inhibit PDE1 activity, especially PDE1A or PDE1B activity.
SUMMARY OF THE INVENTION
[0008] The invention provides optionally substituted 3-(thio, sulfinyl or sulfonyl)-7,8-dihydro-(1H or 2H)-imidazo[1,2-a]pyrazolo[4,3-e]pyrimidin-4(5H)-ones or a substituted 3-(thio, sulfinyl or sulfonyl)-7,8,9-trihydro-(1H or 2H)-pyrimido[1,2-a]pyrazolo[4,3-e]pyrimidin-4(5H)-one, e.g., (1 or 2 and/or 5)-substituted, e.g., a Compound of Formula II:
[0000]
[0000] wherein
(i) L is S, SO or SO 2 ; (ii) R 1 is H or C 1-4 alkyl (e.g., methyl or ethyl); (iii) R 4 is H or C 1-6 alkyl (e.g., methyl, isopropyl) and R 2 and R 3 are, independently, H or C 1-6 alkyl (e.g., methyl or isopropyl) optionally substituted with halo or hydroxy (e.g., R 2 and R 3 are both methyl, or R 2 is H and R 3 is methyl, ethyl, isopropyl or hydroxyethyl), aryl, heteroaryl, (optionally hetero)arylalkoxy, (optionally hetero)arylC 1-6 alkyl, or R 2 and R 3 together form a 3- to 6-membered ring;
or R 2 is H and R 3 and R 4 together form a di-, tri- or tetramethylene bridge (pref. wherein the R 3 and R 4 together have the cis configuration, e.g., where the carbons carrying R 3 and R 4 have the R and S configurations, respectively);
(iv) R 5 is
a) -D-E-F, wherein:
D is C 1-4 alkylene (e.g., methylene, ethylene or prop-2-yn-1-ylenè); E is a single bond, C 2-4 alkynylene (e.g., —C≡C—), arylene (e.g., phenylene) or heteroarylene (e.g., pyridylene); F is
H, aryl (e.g., phenyl), heteroaryl (e.g., pyridyl, diazolyl, triazolyl, for example, pyrid-2-yl, imidazol-1-yl, 1,2,4-triazol-1-yl), halo (e.g., F, Br, Cl), haloC 1-4 alkyl (e.g., trifluoromethyl), —C(O)—R 15 , —N(R 16 )(R 17 ), —S(O) 2 R 21 or C 3-7 cycloalkyl optionally containing at least one atom selected from a group consisting of N or O (e.g., cyclopentyl, cyclohexyl, pyrrolidinyl (e.g., pyrrolidin-3-yl), tetrahydro-2H-pyran-4-yl, or morpholinyl);
wherein D, E and F are independently and optionally substituted with one or more
halo (e.g., F, Cl or Br), C 1-4 alkyl (e.g., methyl), haloC 1-4 alkyl (e.g., trifluoromethyl),
for example, F is heteroaryl, e.g., pyridyl substituted with one or more halo (e.g., 6-fluoropyrid-2-yl, 5-fluoropyrid-2-yl, 6-fluoropyrid-2-yl, 3-fluoropyrid-2-yl, 4-fluoropyrid-2-yl, 4,6-dichloropyrid-2-yl), haloC 1-4 alkyl (e.g., 5-trifluoromethylpyrid-2-yl) or C 1-4 alkyl (e.g., 5-methylpyrid-2-yl), or F is aryl, e.g., phenyl, substituted with one or more halo (e.g., 4-fluorophenyl) or F is a C 3-7 heterocycloalkyl (e.g., pyrrolidinyl) optionally substituted with a C 1-6 alkyl (e.g., 1-methylpyrrolidin-3-yl); or
b) a substituted heteroarylalkyl, e.g., substituted with haloalkyl; c) attached to one of the nitrogens on the pyrazolo portion of Formula I and is a moiety of Formula A
[0000]
wherein X, Y and Z are, independently, N or C, and R 8 , R 9 , R 11 and R 12 are independently H or halogen (e.g., Cl or F), and R 10 is
halogen, C 3-7 cycloalkyl, heteroC 3-7 cycloalkyl (e.g. pyrrolidinyl or piperidinyl), C 1-4 haloalkyl (e.g., trifluoromethyl), aryl (e.g., phenyl), heteroaryl (e.g., pyridyl (for example pyrid-2-yl), or thiadiazolyl (e.g., 1,2,3-thiadiazol-4-yl)), diazolyl, triazolyl, tetrazolyl, arylcarbonyl (e.g., benzoyl), alkylsulfonyl (e.g., methylsulfonyl), heteroarylcarbonyl, or alkoxycarbonyl,
wherein said aryl, heteroaryl, cycloalkyl or heterocycloalkyl is optionally substituted with one or more halo (e.g., F or Cl), C 1-4 alkyl, C 1-4 alkoxy, C 1-4 haloalkyl (e.g., trifluoromethyl), and/or —SH,
preferably R 10 is phenyl, pyridyl, piperidinyl or pyrrolidinyl optionally substituted with the substituents previously defined, e.g. optionally substituted with halo or alkyl;
provided that when X, Y, or Z is nitrogen, R 8 , R 9 , or R 10 , respectively, is not present;
(v) R 6 is
H, C 1-4 alkyl (e.g., methyl), C 3-7 cycloalkyl (e.g., cyclopentyl), aryl (e.g., phenyl), heteroaryl (e.g., pyridyl, for example, pyrid-4-yl), arylC 1-4 alkyl (e.g., benzyl), arylamino (e.g., phenylamino), heterarylamino, N,N-diC 1-4 alkylamino, N,N-diarylamino, N-aryl-N-(arylC 1-4 alkyl)amino (e.g., N-phenyl-N-(1,1′-biphen-4-ylmethyl)amino), or —N(R 18 )(R 19 ); wherein the aryl or heteroaryl is optionally substituted with one or more halo (e.g., F, Cl), hydroxy or C 1-6 alkoxy (e.g., methoxy), for example, R 6 is 4-hydroxyphenyl or 4-fluorophenyl,
(vi) n=0 or 1;
(vii) when n=1, A is —C(R 13 R 14 )—, wherein R 13 and R 14 , are, independently, H or C 1-4 alkyl, aryl, heteroaryl, (optionally hetero)arylC 1-4 alkoxy or (optionally hetero)arylC 1-4 alkyl or R 13 or R 14 can form a bridge with R 2 or R 4 ;
(viii) R 15 is C 1-4 alkyl, haloC 1-4 alkyl, —OH or —OC 1-4 alkyl (e.g., —OCH 3 )
(ix) R 16 and R 17 are independently H or C 1-4 alkyl;
(x) R 18 and R 19 are independently H, C 1-4 alky, C 3-8 cycloalkyl, heteroC 3-8 cycloalkyl, aryl (e.g., phenyl) or heteroaryl, wherein said aryl or heteroaryl is optionally substituted with one or more halo (e.g., fluorophenyl, e.g., 4-fluorophenyl), hydroxy (e.g., hydroxyphenyl, e.g., 4-hydroxyphenyl or 2-hydroxyphenyl), C 1-6 alkyl, haloC 1-6 alkyl, C 1-6 alkoxy, aryl, heteroaryl, or C 3-8 cycloalkyl,
(xi) R 20 is H, C 1-4 alkyl (e.g., methyl) or C 3-7 cycloalkyl,
(xii) R 21 is C 1-6 alkyl;
in free or form.
[0070] In another embodiment, the invention provides a Compound of Formula I:
[0000]
[0000] wherein
(i) L is S, SO or SO 2 ; (ii) R 1 is H or C 1-4 alkyl (e.g., methyl or ethyl); (iii) R 4 is H or C 1-6 alkyl (e.g., methyl, isopropyl) and R 2 and R 3 are, independently, H or C 1-6 alkyl (e.g., methyl or isopropyl) optionally substituted with halo or hydroxy (e.g., R 2 and R 3 are both methyl, or R 2 is H and R 3 is methyl, ethyl, isopropyl or hydroxyethyl), aryl, heteroaryl, (optionally hetero)arylalkoxy, or (optionally hetero)arylC 1-6 alkyl;
or R 2 is H and R 3 and R 4 together form a di-, tri- or tetramethylene bridge (pref. wherein the R 3 and R 4 together have the cis configuration, e.g., where the carbons carrying R 3 and R 4 have the R and S configurations, respectively);
(iv) R 5 is
a) -D-E-F, wherein:
D is C 1-4 alkylene (e.g., methylene, ethylene or prop-2-yn-1-ylene); E is a single bond, C 2-4 alkynylene (e.g., —C≡C—), arylene (e.g., phenylene) or heteroarylene (e.g., pyridylene); F is
H, aryl (e.g., phenyl), heteroaryl (e.g., pyridyl, diazolyl, triazolyl, for example, pyrid-2-yl, imidazol-1-yl, 1,2,4-triazol-1-yl), halo (e.g., F, Br, Cl), haloC 1-4 alkyl (e.g., trifluoromethyl), —C(O)—R 15 , —N(R 16 )(R 17 ), —S(O) 2 R 21 or C 3-7 cycloalkyl optionally containing at least one atom selected from a group consisting of N or O (e.g., cyclopentyl, cyclohexyl, pyrrolidinyl (e.g., pyrrolidin-3-yl), tetrahydro-2H-pyran-4-yl, or morpholinyl);
wherein D, E and F are independently and optionally substituted with one or more
halo (e.g., F, Cl or Br), C 1-4 alkyl (e.g., methyl), haloC 1-4 alkyl (e.g., trifluoromethyl),
for example, F is heteroaryl, e.g., pyridyl substituted with one or more halo (e.g., 6-fluoropyrid-2-yl, 5-fluoropyrid-2-yl, 6-fluoropyrid-2-yl, 3-fluoropyrid-2-yl, 4-fluoropyrid-2-yl, 4,6-dichloropyrid-2-yl), haloC 1-4 alkyl (e.g., 5-trifluoromethylpyrid-2-yl) or C 1-4 alkyl (e.g., 5-methylpyrid-2-yl), or F is aryl, e.g., phenyl, substituted with one or more halo (e.g., 4-fluorophenyl) or F is a C 3-7 heterocycloalkyl (e.g., pyrrolidinyl) optionally substituted with a C 1-6 alkyl (e.g., 1-methylpyrrolidin-3-yl); or
b) a substituted heteroarylalkyl, e.g., substituted with haloalkyl; c) attached to one of the nitrogens on the pyrazolo portion of Formula I and is a moiety of Formula A
[0000]
wherein X, Y and Z are, independently, N or C, and R 8 , R 9 , R 11 and R 12 are independently H or halogen (e.g., Cl or F), and R 10 is halogen, C 1-4 alkyl, C 3-7 cycloalkyl, C 1-4 haloalkyl (e.g., trifluoromethyl), aryl (e.g., phenyl), heteroaryl (e.g., pyridyl (for example pyrid-2-yl), or thiadiazolyl (e.g., 1,2,3-thiadiazol-4-yl)), diazolyl, triazolyl, tetrazolyl, arylcarbonyl (e.g., benzoyl), alkylsulfonyl (e.g., methylsulfonyl), heteroarylcarbonyl, or alkoxycarbonyl; provided that when X, Y, or Z is nitrogen, R 8 , R 9 , or R 10 , respectively, is not present;
(v) R 6 is
H, C 1-4 alkyl (e.g., methyl), C 3-7 cycloalkyl (e.g., cyclopentyl), aryl (e.g., phenyl), heteroaryl (e.g., pyridyl, for example, pyrid-4-yl), arylC 1-4 alkyl (e.g., benzyl), arylamino (e.g., phenylamino), heterarylamino, N,N-diC 1-4 alkylamino, N,N-diarylamino, N-aryl-N-(arylC 1-4 alkyl)amino (e.g., N-phenyl-N-(1,1′-biphen-4-ylmethyl)amino), or —N(R 18 )(R 19 ); wherein the aryl or heteroaryl is optionally substituted with one or more halo (e.g., F, Cl), hydroxy or C 1-6 alkoxy (e.g., methoxy), for example, R 6 is 4-hydroxyphenyl or 4-fluorophenyl,
(vi) n=0 or 1;
(vii) when n=1, A is —C(R 13 R 14 )—, wherein R 13 and R 14 , are, independently, H or C 1-4 alkyl, aryl, heteroaryl, (optionally hetero)arylC 1-4 alkoxy or (optionally hetero)arylC 1-4 alkyl;
(viii) R 15 is C 1-4 alkyl, haloC 1-4 alkyl, —OH or —OC 1-4 alkyl (e.g., —OCH 3 )
(ix) R 16 and R 17 are independently H or C 1-4 alkyl;
(x) R 18 and R 19 are independently H, C 1-4 alky or aryl (e.g., phenyl) wherein said aryl is optionally substituted with one or more halo (e.g., fluorophenyl, e.g., 4-fluorophenyl) or hydroxy (e.g., hydroxyphenyl, e.g., 4-hydroxyphenyl or 2-hydroxyphenyl)
(xi) R N is H, C 1-4 alkyl (e.g., methyl) or C 3-7 cycloalkyl,
(xii) R 21 is C 1-6 alkyl;
in free or salt form.
[0119] The invention further provides compounds of Formula I as follows:
1.1 Formula I, wherein L is a S, SO or SO 2 ; 1.2 Formula I or 1.1, wherein L is a S; 1.3 Formula I or 1.1, wherein L is —SO—; 1.4 Formula I or 1.1, wherein L is —SO 2 —; 1.5 Formula I, or any of 1.1-1.4, wherein R 1 is H or C 1-4 alkyl (e.g., methyl); 1.6 Formula 1.5, wherein R 1 is H; 1.7 Formula 1.5, wherein R 1 is C 1-4 alkyl (e.g., methyl or ethyl); 1.8 Formula I, or any of 1.1-1.7, wherein R 4 is H or C 1-6 alkyl (e.g., methyl, isopropyl) and R 2 and R 3 are, independently, H or C 1-6 alkyl (e.g., methyl or isopropyl) optionally substituted with halo or hydroxy (e.g., R 2 and R 3 are both methyl, or R 2 is H and R 3 is methyl, ethyl, isopropyl or hydroxyethyl), aryl, heteroaryl, (optionally hetero)arylalkoxy, or (optionally hetero)arylC 1-6 alkyl; 1.9 Formula 1.8, wherein R 2 or R 3 is H or C 1-6 alkyl (e.g., methyl or isopropyl); 1.10 Formula 1.8, wherein R 2 or R 3 is H; 1.11 Formula 1.8, wherein R 2 or R 3 is C 1-6 alkyl (e.g., methyl or isopropyl); 1.12 Formula 1.8, wherein R 2 or R 3 is methyl; 1.13 Formula 1.8, wherein R 2 or R 3 is isopropyl; 1.14 Formula I, or any of 1.1-1.7, wherein R 2 is H and R 3 and R 4 together form a di-, tri- or tetramethylene bridge (pref. wherein the R 3 and R 4 together have the cis configuration, e.g., where the carbons carrying R 3 and R 4 have the R and S configurations, respectively); 1.15 Formula I or any of 1.1-1.14, wherein R 5 is -D-E-F; 1.16 Formula 1.15, wherein D is C 1-4 alkylene (e.g., methylene, ethylene or prop-2-yn-1-ylene); 1.17 Formula 1.16, wherein D is methylene; 1.18 Any of formulae 1.15-1.17, wherein E is a single bond, C 2-4 alkynylene (e.g., —C≡C—), arylene (e.g., phenylene) or heteroarylene (e.g., pyridylene); 1.19 Any of formulae 1.15-1.17, wherein E is arylene (e.g., phenylene); 1.20 Any of formulae 1.15-1.17, wherein E is phenylene; 1.21 Any of formulae 1.15-1.17, wherein E is heteroarylene (e.g., pyridylene); 1.22 Any of formulae 1.15-1.17, wherein E is phenylene wherein F is para-substituted; 1.23 Any of formulae 1.15-1.17, wherein E is heteroarylene (e.g., pyridylene); 1.24 Any of formulae 1.15-1.17, wherein E is a single bond; 1.25 Any of formulae 1.15-1.24, wherein F is H, aryl (e.g., phenyl), heteroaryl (e.g., pyridyl, diazolyl, triazolyl, for example, pyrid-2-yl, imidazol-1-yl, 1,2,4-triazol-1-yl), halo (e.g., F, Br, Cl), haloC 1-4 alkyl (e.g., trifluoromethyl), —C(O)—R 15 , —N(R 16 )(R 17 ), —S(O) 2 R 21 or C 3-7 cycloalkyl optionally containing at least one atom selected from a group consisting of N or O (e.g., cyclopentyl, cyclohexyl, pyrrolidinyl (e.g., pyrrolidin-3-yl), tetrahydro-2H-pyran-4-yl, or morpholinyl); 1.26 Formula 1.25, wherein F is haloC 1-4 alkyl (e.g., trifluoromethyl); 1.27 Formula 1.25, wherein F is trifluoromethyl; 1.28 Formula 1.25, wherein F is halo (e.g., F, Br, Cl); 1.29 Formula 1.25, wherein F is Cl; 1.30 Formula 1.25, wherein F is heteroaryl (e.g., pyridyl, e.g., pyrid-2-yl); 1.31 Formula 1.25, wherein F is pyridyl; 1.32 Formula 1.25, wherein F is pyrid-2-yl; 1.33 Formula 1.25, wherein F is C 3-7 cycloalkyl optionally containing at least one atom selected from a group consisting of N or O (e.g., cyclopentyl, cyclohexyl, pyrrolidinyl (e.g., pyrrolidin-3-yl), tetrahydro-2H-pyran-4-yl, morpholinyl); 1.34 Formula 1.25, wherein F is cyclohexyl; 1.35 Formula 1.25, wherein F is pyrrolidinyl (e.g., pyrrolidin-3-yl);
[0155] 1.36 Formula 1.25, wherein F is cyclopentyl;
1.37 Formula 1.25, wherein F is tetrahydro-2H-pyran-4-yl; 1.38 Formula 1.25, wherein F is aryl (e.g., phenyl); 1.39 Formula 1.25, wherein F is phenyl; 1.40 Formula 1.25, wherein F is 4-chlorophenyl;
[0160] 1.41 Formula 1.25, wherein F is —S(O) 2 R 21 wherein R 21 is C 1-6 alkyl (e.g., methyl);
1.42 Formula 1.25, wherein F is —C(O)—R 15 and R 15 is C 1-4 alky (e.g., methyl), haloC 1-4 alkyl (e.g., trifluoromethyl), —OH or —OC 1-4 alkyl (e.g., —OCH 3 ); 1.43 Any of formulae 1.15-1.42, wherein D, E and F are independently and optionally substituted with one or more halo (e.g., F, Cl or Br), C 1-4 alkyl (e.g., methyl), haloC 1-4 alkyl (e.g., trifluoromethyl), for example, F is heteroaryl, e.g., pyridyl substituted with one or more halo (e.g., 6-fluoropyrid-2-yl, 5-fluoropyrid-2-yl, 6-fluoropyrid-2-yl, 3-fluoropyrid-2-yl, 4-fluoropyrid-2-yl, 4,6-dichloropyrid-2-yl), haloC 1-4 alkyl (e.g., 5-trifluoromethylpyrid-2-yl) or C 1-4 alkyl (e.g., 5-methylpyrid-2-yl), or F is aryl, e.g., phenyl, substituted with one or more halo (e.g., 4-fluorophenyl), or F is a or F is a C 3-7 heterocycloalkyl (e.g., pyrrolidinyl) optionally substituted with a C 1-6 alkyl (e.g., 1-methylpyrrolidin-3-yl); 1.44 Formula 1.43, wherein F is substituted with one or more halo (e.g., F, Cl or Br), C1-4 alkyl (e.g., methyl), halo C1-4 alkyl (e.g., trifluoromethyl); 1.45 Formula 1.43, wherein F is 6-fluoropyrid-2-yl; 1.46 Formula 1.43, wherein F is 3-fluoropyrid-2-yl; 1.47 Formula 1.43, wherein F is 4-fluoropyrid-2-yl; 1.48 Formula 1.43, wherein F is 5-fluoropyrid-2-yl; 1.49 Formula 1.43, wherein F is heteroaryl, e.g., pyridyl, optionally substituted with one or more haloC 1-4 alkyl (e.g., 5-trifluoromethylpyrid-2-yl; 1.50 Formula 1.43, wherein F is 5-trifluoromethylpyrid-2-yl; 1.51 Formula 1.43, wherein F is heteroaryl, e.g., pyridyl, optionally substituted with one or more C 1-4 alkyl (e.g., 5-methylpyrid-2-yl); 1.52 Formula 1.43, wherein F is 5-methylpyrid-2-yl; 1.53 Formula 1.25, wherein F is —C(O)—R 15 and R 15 is methyl; 1.54 Formula 1.25, wherein F is —C(O)—R 15 and R 15 is trifluoromethyl; 1.55 Formula 1.25, wherein F is —C(O)—R 15 and R 15 is —OH; 1.56 Formula 1.25, wherein F is —C(O)—R 15 and R 15 is —OC 1-4 alkyl (e.g., —OCH 3 ); 1.57 Formula 1.25, wherein F is —C(O)—R 15 and R 15 is —OCH 3 ; 1.58 Formula 1.25, wherein F is —N(R 16 )(R 17 ); 1.59 Formula I or any of 1.1-1.14, wherein R 5 is a substituted heteroarylalkyl, e.g., substituted with haloalkyl; 1.60 Formula I or any of 1.1-1.14, wherein R 5 is attached to one of the nitrogens on the pyrazolo portion of Formula I and is a moiety of Formula A
[0000]
wherein X, Y and Z are, independently, N or C, and R 8 , R 9 , R 11 and R 12 are independently H or halogen (e.g., Cl or F), and R 10 is halogen, C 1-4 alkyl, C 3-7 cycloalkyl, C 1-4 haloalkyl (e.g., trifluoromethyl), aryl (e.g., phenyl), heteroaryl (e.g., pyridyl (for example pyrid-2-yl), or thiadiazolyl (e.g., 1,2,3-thiadiazol-4-yl)), diazolyl, triazolyl, tetrazolyl, arylcarbonyl (e.g., benzoyl), alkylsulfonyl (e.g., methylsulfonyl), heteroarylcarbonyl, or alkoxycarbonyl; provided that when X, Y, or Z is nitrogen, R 8 , R 9 , or R 10 , respectively, is not present
1.61 Formula 1.60, wherein R 5 is a substituted heteroarylmethyl, e.g., para-substituted with haloalkyl;
1.62 Formula 1.60, wherein R 5 is a moiety of Formula A wherein R 8 , R 9 , R 11 , and R 12 are H and R 10 is phenyl;
1.63 Formula 1.60, wherein R 5 is a moiety of Formula A wherein R 8 , R 9 , R 11 , and R 12 are H and R 10 is pyridyl or thiadiazolyl;
1.64 Formula 1.60, wherein R 5 is a moiety of Formula A wherein R 8 , R 9 , R 11 , and R 12 are, independently, H or halogen, and R 10 is haloalkyl;
1.65 Formula 1.60, wherein R 5 is a moiety of Formula A wherein R 8 , R 9 , R 11 , and R 12 are, independently, H, and R 10 is alkyl sulfonyl;
1.66 Formula I or any of 1.1-1.65, wherein R 6 is H, C 1-4 alkyl (e.g., methyl), C 3-7 cycloalkyl (e.g., cyclopentyl), aryl, heteroaryl, arylC 1-4 alkyl (e.g., benzyl), arylamino (e.g., phenylamino), heterarylamino, N,N-diC 1-4 alkylamino, N,N-diarylamino, N-aryl-N-(arylC 1-4 alkyl)amino (e.g., N-phenyl-N-(1,1′-biphen-4-ylmethyl)amino), or —N(R 18 )(R 19 ), wherein the aryl or heteroaryl is optionally substituted with one or more halo (e.g., F, Cl), hydroxy or C 1-6 alkoxy (e.g., methoxy);
1.67 Formula 1.66, wherein R 6 is H;
1.68 Formula 1.66, wherein R 6 is C 1-4 alkyl (e.g., methyl);
1.69 Formula 1.66, wherein R 6 is C 3-7 cycloalkyl (e.g., cyclopentyl);
1.70 Formula 1.66, wherein R 6 is aryl (e.g., phenyl) optionally substituted with one or more halo (e.g., F, Cl), hydroxy or C 1-6 alkoxy (e.g., methoxy);
1.71 Formula 1.66, wherein R 6 is fluorophenyl (e.g., 4-fluorophenyl) or hydroxyphenyl (e.g., 4-hydroxyphenyl);
1.72 Formula I or any of 1.1-1.71, wherein n=0;
1.73 Formula I or any of 1.1-1.71, wherein n=1;
1.74 Formula 1.73, wherein n=1, A is —C(R 13 R 14 )—, wherein R 13 and R 14 , are, independently, H or C 1-4 alkyl, aryl, heteroaryl, (optionally hetero)arylC 1-4 alkoxy or (optionally hetero)arylC 1-4 alkyl;
1.75 any of the preceding formulae wherein the compound is selected from a group consisting of:
[0000]
1.76 any of the preceding formulae wherein the compounds inhibit phosphodiesterase-mediated (e.g., PDE1-mediated, especially PDE1B-mediated) hydrolysis of cGMP, e.g., with an IC 50 of less than 1 μM, preferably less than 500 nM, more preferably less than 50 nM in an immobilized-metal affinity particle reagent PDE assay, for example, as described in Example 9,
in free or salt form.
[0197] In another embodiment, the invention provides a Compound of Formula I or II, wherein R 6 is:
H, C 1-4 alkyl (e.g., methyl), C 3-7 cycloalkyl (e.g., cyclopentyl), aryl (e.g., phenyl), heteroaryl (e.g., pyridyl, for example, pyrid-4-yl), arylC 1-4 alkyl (e.g., benzyl), wherein the aryl or heteroaryl is optionally substituted with one or more halo (e.g., F, Cl), hydroxy or C 1-6 alkoxy (e.g., methoxy), for example, R 6 is 4-hydroxyphenyl or 4-fluorophenyl,
and the remaining substituents are as previously defined in Formula I or II or any of 1.1-1.76, in free or salt form.
[0205] In another embodiment, the invention provides a Compound of Formula I or II, wherein
R 5 is attached to one of the nitrogens on the pyrazolo portion of Formula I or II and is a moiety of Formula A
[0000]
wherein X, Y and Z are, independently, N or C, and R 8 , R 9 , R 11 and R 12 are independently H or halogen (e.g., Cl or F), and R 10 is
halogen, C 1-4 alkyl, C 3-7 cycloalkyl, heterocycloalkyl (e.g., pyrrolidinyl or piperidinyl), C 1-4 haloalkyl (e.g., trifluoromethyl), aryl (e.g., phenyl), heteroaryl (e.g., pyridyl (for example pyrid-2-yl), or thiadiazolyl (e.g., 1,2,3-thiadiazol-4-yl)), diazolyl, triazolyl, tetrazolyl, arylcarbonyl (e.g., benzoyl), alkylsulfonyl (e.g., methylsulfonyl), heteroarylcarbonyl, or alkoxycarbonyl,
wherein said aryl, heteroaryl, cycloalkyl or heterocycloalkyl is optionally substituted with one or more halo (e.g., F or Cl), C 1-4 alkyl, C 1-4 alkoxy, C 1-4 haloalkyl (e.g., trifluoromethyl), and/or —SH,
provided that when X, Y, or Z is nitrogen, R 8 , R 9 , or R 10 , respectively, is not present;
R 6 is:
H, C 1-4 alkyl (e.g., methyl), C 3-7 cycloalkyl (e.g., cyclopentyl), aryl (e.g., phenyl), heteroaryl (e.g., pyridyl, for example, pyrid-4-yl), arylC 1-4 alkyl (e.g., benzyl), wherein the aryl or heteroaryl is optionally substituted with one or more halo (e.g., F, Cl), hydroxy or C 1-6 alkoxy (e.g., methoxy), for example, R 6 is 4-hydroxyphenyl or 4-fluorophenyl,
and the remaining substituents are as previously defined in Formula I or II or any of 1.1-1.76, in free or salt form.
[0229] In still another embodiment, the invention provides a Compound of Formula I or II, wherein
R 5 is attached to one of the nitrogens on the pyrazolo portion of Formula I or II and is a moiety of Formula A
[0000]
wherein X, Y and Z are, independently, N or C, and R 8 , R 9 , R 11 and R 12 are independently H or halogen (e.g., Cl or F), and R 10 is
halogen, C 3-7 cycloalkyl, heterocycloalkyl (e.g., pyrrolidinyl or piperidinyl), C 1-4 haloalkyl (e.g., trifluoromethyl), aryl (e.g., phenyl), heteroaryl (e.g., pyridyl (for example pyrid-2-yl), or thiadiazolyl (e.g., 1,2,3-thiadiazol-4-yl)), diazolyl, triazolyl, tetrazolyl, arylcarbonyl (e.g., benzoyl), alkylsulfonyl (e.g., methylsulfonyl), heteroarylcarbonyl, or alkoxycarbonyl,
wherein said aryl, heteroaryl, cycloalkyl or heterocycloalkyl is optionally substituted with one or more halo (e.g., F or Cl), C 1-4 alkyl, C 1-4 alkoxy, C 1-4 haloalkyl (e.g., trifluoromethyl), and/or —SH,
provided that when X, Y, or Z is nitrogen, R 8 , R 9 , or R 10 , respectively, is not present;
R 6 is:
H, C 1-4 alkyl (e.g., methyl), aryl (e.g., phenyl), heteroaryl (e.g., pyridyl, for example, pyrid-4-yl), wherein the aryl or heteroaryl is optionally substituted with one or more halo (e.g., F, Cl), hydroxy or C 1-6 alkoxy (e.g., methoxy), for example, R 6 is 4-hydroxyphenyl or 4-fluorophenyl,
and the remaining substituents are as previously defined in Formula I or II or any of 1.1-1.76, in free or salt form.
[0250] In yet another embodiment, the invention provides a Compound of Formula I or H, wherein
R 5 is attached to one of the nitrogens on the pyrazolo portion of Formula I or II and is a moiety of Formula A
[0000]
wherein X, Y and Z are, independently, N or C, and R 8 , R 9 , R 11 and R 12 are independently H or halogen (e.g., Cl or F), and R 10 is
heterocycloalkyl (e.g., pyrrolidinyl or piperidinyl), aryl (e.g., phenyl), heteroaryl (e.g., pyridyl (for example pyrid-2-yl), or thiadiazolyl (e.g., 1,2,3-thiadiazol-4-yl)), diazolyl, triazolyl, tetrazolyl,
wherein said aryl, heteroaryl or heterocycloalkyl is optionally substituted with one or more halo (e.g., F or Cl), C 1 alkyl, C 1-4 alkoxy, C 1-4 haloalkyl (e.g., trifluoromethyl), and/or —SH, provided that when X, Y, or Z is nitrogen, R 8 , R 9 , or R 10 , respectively, is not present;
R 6 is:
H, C 1-4 alkyl (e.g., methyl), aryl (e.g., phenyl), heteroaryl (e.g., pyridyl, for example, pyrid-4-yl), wherein the aryl or heteroaryl is optionally substituted with one or more halo (e.g., F, hydroxy or C 1-6 alkoxy (e.g., methoxy), for example, R 6 is 4-hydroxyphenyl or 4-fluorophenyl,
and the remaining substituents are as previously defined in Formula I or II or any of 1.1-1.76, in free or salt form.
[0263] If not otherwise specified or clear from context, the following terms herein have the following meanings
(a) “Alkyl” as used herein is a saturated or unsaturated hydrocarbon moiety, preferably saturated, preferably having one to six carbon atoms, which may be linear or branched, and may be optionally mono-, di- or tri-substituted, e.g., with halogen (e.g., chloro or fluoro), hydroxy, or carboxy. (b) “Cycloalkyl” as used herein is a saturated or unsaturated nonaromatic hydrocarbon moiety, preferably saturated, preferably comprising three to nine carbon atoms, at least some of which form a nonaromatic mono- or bicyclic, or bridged cyclic structure, and which may be optionally substituted, e.g., with halogen (e.g., chloro or fluoro), hydroxy, or carboxy. Wherein the cycloalkyl optionally contains one or more atoms selected from N and O and/or S, said cycloalkyl may also be a heterocycloalkyl. (c) “Heterocycloalkyl” is, unless otherwise indicated, saturated or unsaturated nonaromatic hydrocarbon moiety, preferably saturated, preferably comprising three to nine carbon atoms, at least some of which form a nonaromatic mono- or bicyclic, or bridged cyclic structure, wherein at least one carbon atom is replaced with N, O or S, which heterocycloalkyl may be optionally substituted, e.g., with halogen (e.g., chloro or fluoro), hydroxy, or carboxy. (d) “Aryl” as used herein is a mono or bicyclic aromatic hydrocarbon, preferably phenyl, optionally substituted, e.g., with alkyl (e.g., methyl), halogen (e.g., chloro or fluoro), haloalkyl (e.g., trifluoromethyl), hydroxy, carboxy, or an additional aryl or heteroaryl (e.g., biphenyl or pyridylphenyl). (e) “Heteroaryl” as used herein is an aromatic moiety wherein one or more of the atoms making up the aromatic ring is sulfur or nitrogen rather than carbon, e.g., pyridyl or thiadiazolyl, which may be optionally substituted, e.g., with alkyl, halogen, haloalkyl, hydroxy or carboxy. (f) Wherein E is phenylene, the numbering is as follows:
[0000]
(g) It is intended that wherein the substituents end in “ene”, for example, alkylene, phenylene or arylalkylene, said substitutents are intended to bridge or be connected to two other substituents. Therefore, methylene is intended to be —CH 2 — and phenylene intended to be —C 6 H 4 — and arylalkylene is intended to be —C 6 H 4 —CH 2 — or —CH 2 —C 6 H 4 —.
[0271] Compounds of the Invention, e.g., substituted 4,5,7,8-tetrahydro-(1H or 2H)-imidazo[1,2-a]pyrazolo[4,3-e]pyrimidine or a substituted 3-(thio, sulfinyl or sulfonyl)-7,8,9-trihydro-(1H or 2H)-pyrimido[1,2-a]pyrazolo[4,3-e]pyrimidin-4(5H)-one compounds, e.g., Compounds of Formula I, e.g., any of formulae 1.1-1.76, may exist in free or salt form, e.g., as acid addition salts. In this specification unless otherwise indicated, language such as “Compounds of the Invention” is to be understood as embracing the compounds in any form, for example free or acid addition salt form, or where the compounds contain acidic substituents, in base addition salt form. The Compounds of the Invention are intended for use as pharmaceuticals, therefore pharmaceutically acceptable salts are preferred. Salts which are unsuitable for pharmaceutical uses may be useful, for example, for the isolation or purification of free Compounds of the Invention or their pharmaceutically acceptable salts, are therefore also included.
[0272] Compounds of the Invention may in some cases also exist in prodrug form. A prodrug form is compound which converts in the body to a Compound of the Invention. For example when the Compounds of the Invention contain hydroxy or carboxy substituents, these substituents may form physiologically hydrolysable and acceptable esters. As used herein, “physiologically hydrolysable and acceptable ester” means esters of Compounds of the Invention which are hydrolysable under physiological conditions to yield acids (in the case of Compounds of the Invention which have hydroxy substituents) or alcohols (in the case of Compounds of the Invention which have carboxy substituents) which are themselves physiologically tolerable at doses to be administered. Therefore, wherein the Compound of the Invention contains a hydroxy group, for example, Compound-OH, the acyl ester prodrug of such compound, i.e., Compound-O—C(O)—C 1-4 alkyl, can hydrolyze in the body to form physiologically hydrolysable alcohol (Compound-OH) on the one hand and acid on the other (e.g., HOC(O)—C 1-4 alkyl). Alternatively, wherein the Compound of the Invention contains a carboxylic acid, for example, Compound-C(O)OH, the acid ester prodrug of such compound, Compound-C(O)O—C 1-4 alkyl can hydrolyze to form Compound-C(O)OH and HO—C 1-4 alkyl. As will be appreciated the term thus embraces conventional pharmaceutical prodrug forms.
[0273] The invention also provides methods of making the Compounds of the Invention and methods of using the Compounds of the Invention for treatment of diseases and disorders as set forth below (especially treatment of diseases characterized by reduced dopamine D1 receptor signaling activity, such as Parkinson's disease, Tourette's Syndrome, Autism, fragile X syndrome, ADHD, restless leg syndrome, depression, cognitive impairment of schizophrenia, narcolepsy and diseases that may be alleviated by the enhancement of progesterone-signaling such as female sexual dysfunction), or a disease or disorder such as psychosis or glaucoma). This list is not intended to be exhaustive and may include other diseases and disorders as set forth below.
[0274] In another embodiment, the invention further provides a pharmaceutical composition comprising a Compound of the Invention, in free, pharmaceutically acceptable salt or prodrug form, in admixture with a pharmaceutically acceptable carrier.
DETAILED DESCRIPTION OF THE INVENTION
Methods of Making Compounds of the Invention
[0275] The compounds of the Invention and their pharmaceutically acceptable salts may be made using the methods as described and exemplified herein and by methods similar thereto and by methods known in the chemical art. Such methods include, but not limited to, those described below. If not commercially available, starting materials for these processes may be made by procedures, which are selected from the chemical art using techniques which are similar or analogous to the synthesis of known compounds. Various starting materials and/or Compounds of the Invention may be prepared using methods described in WO 2006/133261 and PCT/US2007/070551. All references cited herein are hereby incorporated by reference in their entirety.
[0276] The Compounds of the Invention include their enantiomers, diastereoisomers and racemates, as well as their polymorphs, hydrates, solvates and complexes. Some individual compounds within the scope of this invention may contain double bonds. Representations of double bonds in this invention are meant to include both the E and the Z isomer of the double bond. In addition, some compounds within the scope of this invention may contain one or more asymmetric centers. This invention includes the use of any of the optically pure stereoisomers as well as any combination of stereoisomers.
[0277] It is also intended that the Compounds of the Invention encompass their stable and unstable isotopes. Stable isotopes are nonradioactive isotopes which contain one additional neutron compared to the abundant nuclides of the same species (i.e., element). It is expected that the activity of compounds comprising such isotopes would be retained, and such compound would also have utility for measuring pharmacokinetics of the non-isotopic analogs. For example, the hydrogen atom at a certain position on the Compounds of the Invention may be replaced with deuterium (a stable isotope which is non-raradioactive). Examples of known stable isotopes include, but not limited to, deuterium, 13 C, 15 N, 18 O. Alternatively, unstable isotopes, which are radioactive isotopes which contain additional neutrons compared to the abundant nuclides of the same species (i.e., element), e.g., 123 I, 131 I, 125 I, 11 C, 18 F, may replace the corresponding abundant species of I, C and F. Another example of useful isotope of the compound of the invention is the 11 C isotope. These radio isotopes are useful for radio-imaging and/or pharmacokinetic studies of the compounds of the invention.
[0278] Melting points are uncorrected and (dec) indicates decomposition. Temperature are given in degrees Celsius (° C.); unless otherwise stated, operations are carried out at room or ambient temperature, that is, at a temperature in the range of 18-25° C. Chromatography means flash chromatography on silica gel; thin layer chromatography (TLC) is carried out on silica gel plates. NMR data is in the delta values of major diagnostic protons, given in parts per million (ppm) relative to tetramethylsilane (TMS) as an internal standard. Conventional abbreviations for signal shape are used. Coupling constants (J) are given in Hz. For mass spectra (MS), the lowest mass major ion is reported for molecules where isotope splitting results in multiple mass spectral peaks Solvent mixture compositions are given as volume percentages or volume ratios. In cases where the NMR spectra are complex, only diagnostic signals are reported.
[0279] Terms and Abbreviations:
[0280] BuLi=n-butyllithium
[0281] Bu t OH=tert-butyl alcohol,
[0282] CAN=ammonium cerium (IV) nitrate,
[0283] DIPEA=diisopropylethylamine,
[0284] DMF=N,N-dimethylforamide,
[0285] DMSO=dimethyl sulfoxide,
[0286] Et 2 O=diethyl ether,
[0287] EtOAc=ethyl acetate,
[0288] equiv.=equivalent(s),
[0289] h=hour(s),
[0290] HPLC=high performance liquid chromatography,
[0291] LDA=lithium diisopropylamide
[0292] MeOH=methanol,
[0293] NBS=N-bromosuccinimide
[0294] NCS=N-chlorosuccinimide
[0295] NaHCO 3 =sodium bicarbonate,
[0296] NH 4 OH=ammonium hydroxide,
[0297] Pd 2 (dba) 3 =tris[dibenzylideneacetone]dipalladium(0)
[0298] PMB=p-methoxybenzyl,
[0299] POCl 3 =phosphorous oxychloride,
[0300] SOCl 2 =thionyl chloride,
[0301] TFA=trifluoroacetic acid,
[0302] TFMSA=trifluoromethanesulfonic acid
[0303] THF=tetrahedrofuran.
[0304] The synthetic methods in this invention are illustrated below. The significances for the R groups are as set forth above for formula I or II unless otherwise indicated.
[0305] In an aspect of the invention, intermediate compounds of formula IIb can be synthesized by reacting a compound of formula IIa with a dicarboxylic acid, acetic anhydride and acetic acid mixing with heat for about 3 hours and then cooled:
[0000]
[0306] wherein R 1 is methyl.
[0307] Intermediate IIc can be prepared by for example reacting a compound of IIb with for example a chlorinating compound such as POCl 3 , sometimes with small amounts of water and heated for about 4 hours and then cooled
[0000]
[0308] Intermediate IId may be formed by reacting a compound of IIc with for example a P 1 —X in a solvent such as DMF and a base such as K 2 CO 3 at room temperature or with heating:
[0000]
[0000] wherein P 1 is a protective group [e.g., p-methoxybenzyl group (PMB)]; X is a leaving group such as a halogen, mesylate, or tosylate.
[0309] Intermediate IIe may be prepared by reacting a compound of IId with hydrazine or hydrazine hydrate in a solvent such as methanol and refluxed for about 4 hours and then cooled:
[0000]
[0310] Intermediate IVa may be formed by for example reacting a compound of IIe with POCl 3 and DMF:
[0000]
[0311] wherein R 1 is as defined previously in Formula I or II, e.g., such as a methyl group.
[0312] Intermediate IVb may be formed by reacting a compound of IVa with for example a R 5 —X in a solvent such as DMF and a base such as K 2 CO 3 at room temperature or with heating:
[0000]
[0313] Intermediate IVc may be synthesized from a compound of IVb by removing the protective group P 1 with an appropriate method. For example, if P 1 is a PMB group, then it can be removed with CAN or TFA/TFMSA at room temperature:
[0000]
[0314] Intermediate IVd can be prepared by reacting a compound of IVc with for example a chlorinating compound such as POCl 3 and refluxed for about 2 days, or heated at 150˜200° C. for about 10 min in a sealed vial with a microwave instrument and then cooled:
[0000]
[0315] Intermediate IVe can be formed by reacting a compound of IVd with an amino alcohol under basic condition in a solvent such as DMF and heated overnight then cooled:
[0000]
[0316] Alternatively, intermediate IVe can be synthesized directly from a compound of IVc by reacting with an amino alcohol and a coupling reagent such as BOP in the presence of a base such as DBU:
[0000]
[0317] wherein all the substituents are as defined previously.
[0318] Compound IVf may be formed by reacting a compound of IVe with for example a dehydrating/halogenating agent such as SOCl 2 in a solvent such as CH 2 Cl 2 at room temperature overnight or heated at 35° C. for several hours, and then cooled.
[0000]
[0319] Compound IVg may be formed by reacting a compound of IVf with for example a halogenating agent such as NCS and a base such as LDA in a solvent such as THF at low temperature for several hours.
[0000]
[0320] Alternatively, Compound IVg may be formed by reacting a compound of IVf with for example a halogenating agent such as hexachloroethane and a base such as LiHMDS in a solvent such as THF at low temperature for several hours:
[0000]
[0321] Compound I may be formed by reacting a compound of IVg with R 6 -LH for example a thiol upon heating.
[0000]
[0322] Alternatively, compound I may be formed by reacting a compound of IVf with a thiol R 6 -LH or a disulfide R 6 -L-L-R 6 in the presence of a strong base, such as a lithium reagent (e.g. LiHMDS) in a solvent such as THF.
[0323] The corresponding sulfinyl or sulfonyl derivative may be formed by reacting the 3-thio compound (e.g., wherein L is —S—) with an oxidizer such as a peroxide (e.g. oxone or hydrogen peroxide) at room temperature in a solvent such as acetonitrile.
[0324] In another aspect of the invention, The invention thus provides methods of making Compounds of Formula I or II, for example, comprising reacting Compounds 1-A with, for example, R 5 —X, in a solvent such as DMF and a base such as K 2 CO 3 at room temperature or with heating:
[0000]
[0000] wherein all the substitutents are as defined previously; X is a leaving group such as a halogen, mesylate, or tosylate.
[0325] The thio Compounds of the Invention, e.g., Formula I or II wherein L is S or Compound (I)-B may be prepared by reacting compound (IVf), e.g., with a disulfide and lithium bis(trimethylsilyl)azanide (LiHMDS).
[0000]
[0326] The sulfinyl or sulfonyl derivatives of the Invention, e.g., Formula I or II, wherein L is SO or SO 2 may be prepared by (I)-B oxidation using, e.g. oxone, in a solvent such as acetonitrile and methanol.
[0327] Methods of Using Compounds of the Invention
[0328] The Compounds of the Invention are useful in the treatment of diseases characterized by disruption of or damage to cAMP and cGMP mediated pathways, e.g., as a result of increased expression of PDE1 or decreased expression of cAMP and cGMP due to inhibition or reduced levels of inducers of cyclic nucleotide synthesis, such as dopamine and nitric oxide (NO). By preventing the degradation of cAMP and cGMP by PDE1B, thereby increasing intracellular levels of cAMP and cGMP, the Compounds of the Invention potentiate the activity of cyclic nucleotide synthesis inducers.
[0329] The invention provides methods of treatment of any one or more of the following conditions:
(i) Neurodegenerative diseases, including Parkinson's disease, restless leg, tremors, dyskinesias, Huntington's disease, Alzheimer's disease, and drug-induced movement disorders; (ii) Mental disorders, including depression, attention deficit disorder, attention deficit hyperactivity disorder, bipolar illness, anxiety, sleep disorders, e.g., narcolepsy, cognitive impairment, dementia, Tourette's syndrome, autism, fragile X syndrome, psychostimulant withdrawal, and drug addiction; (iii) Circulatory and cardiovascular disorders, including cerebrovascular disease, stroke, congestive heart disease, hypertension, pulmonary hypertension, and sexual dysfunction; (iv) Respiratory and inflammatory disorders, including asthma, chronic obstructive pulmonary disease, and allergic rhinitis, as well as autoimmune and inflammatory diseases; (v) Any disease or condition characterized by low levels of cAMP and/or cGMP (or inhibition of cAMP and/or cGMP signaling pathways) in cells expressing PDE1; and/or (vi) Any disease or condition characterized by reduced dopamine D1 receptor signaling activity,
comprising administering an effective amount of a Compound of the Invention, e.g., a compound according to any of Formula I or any of 1.1-1.76, in free, pharmaceutically acceptable salt or prodrug form, to a human or animal patient in need thereof. In another aspect, the invention provides a method of treatment of the conditions disclosed above comprising administering a therapeutically effective amount of a Compound of Formula II, in free or pharmaceutically acceptable salt form.
[0336] In an especially preferred embodiment, the invention provides methods of treatment or prophylaxis for narcolepsy. In this embodiment, PDE 1 Inhibitors may be used as a sole therapeutic agent, but may also be used in combination or for co-administration with other active agents. Thus, the invention further comprises a method of treating narcolepsy comprising administering simultaneously, sequentially, or contemporaneously administering therapeutically effective amounts of
(i) a PDE 1 Inhibitor, e.g., a compound according to any of Formula I or any of 1.1-1.76, and (ii) a compound to promote wakefulness or regulate sleep, e.g., selected from (a) central nervous system stimulants-amphetamines and amphetamine like compounds, e.g., methylphenidate, dextroamphetamine, methamphetamine, and pemoline; (b) modafinil, (c) antidepressants, e.g., tricyclics (including imipramine, desipramine, clomipramine, and protriptyline) and selective serotonin reuptake inhibitors (including fluoxetine and sertraline); and/or (d) gamma hydroxybutyrate (GHB).
in free, pharmaceutically acceptable salt or prodrug form, to a human or animal patient in need thereof. In still another embodiment, the methods of treatment or prophylaxis for narcolepsy as hereinbefore described, comprises administering a therapeutically effective amount of a Compound of Formula II as hereinbefore described, in free or pharmaceutically acceptable salt form, as a sole therapeutic agent or use in combination for co-administered with another active agent.
[0339] In another embodiment, the invention further provides methods of treatment or prophylaxis of a condition which may be alleviated by the enhancement of the progesterone signaling comprising administering an effective amount of a Compound of the Invention, e.g., a compound according to any of Formula I or any of any of 1.1-1.76, in free, pharmaceutically acceptable salt or prodrug form, to a human or animal patient in need thereof. The invention also provides methods of treatment as disclosed here, comprising administering a therapeutically effective amount of a Compound of Formula II, in free or pharmaceutically acceptable salt form. Disease or condition that may be ameliorated by enhancement of progesterone signaling include, but are not limited to, female sexual dysfunction, secondary amenorrhea (e.g., exercise amenorrhoea, anovulation, menopause, menopausal symptoms, hypothyroidism), pre-menstrual syndrome, premature labor, infertility, for example infertility due to repeated miscarriage, irregular menstrual cycles, abnormal uterine bleeding, osteoporosis, autoimmmune disease, multiple sclerosis, prostate enlargement, prostate cancer, and hypothyroidism. For example, by enhancing progesterone signaling, the PDE 1 inhibitors may be used to encourage egg implantation through effects on the lining of uterus, and to help maintain pregnancy in women who are prone to miscarriage due to immune response to pregnancy or low progesterone function. The novel PDE 1 inhibitors, e.g., as described herein, may also be useful to enhance the effectiveness of hormone replacement therapy, e.g., administered in combination with estrogen/estradiol/estriol and/or progesterone/progestins in postmenopausal women, and estrogen-induced endometrial hyperplasia and carcinoma. The methods of the invention are also useful for animal breeding, for example to induce sexual receptivity and/or estrus in a nonhuman female mammal to be bred.
[0340] In this embodiment, PDE 1 Inhibitors may be used in the foregoing methods of treatment or prophylaxis as a sole therapeutic agent, but may also be used in combination or for co-administration with other active agents, for example in conjunction with hormone replacement therapy. Thus, the invention further comprises a method of treating disorders that may be ameliorated by enhancement of progesterone signaling comprising administering simultaneously, sequentially, or contemporaneously administering therapeutically effective amounts of
(i) a PDE 1 Inhibitor, e.g., a compound according to any of Formula I or any of any of 1.1-1.76, and (ii) a hormone, e.g., selected from estrogen and estrogen analogues (e.g., estradiol, estriol, estradiol esters) and progesterone and progesterone analogues (e.g., progestins)
in free, pharmaceutically acceptable salt or prodrug form, to a human or animal patient in need thereof. In another embodiment, the invention provides the method described above wherein the PDE 1 inhibitor is a Compound of Formula II, in free or pharmaceutically acceptable salt form.
[0343] The invention also provides a method for enhancing or potentiating dopamine D1 intracellular signaling activity in a cell or tissue comprising contacting said cell or tissue with an amount of a Compound of the Invention, e.g., Formula I or any of any of 1.1-1.76, sufficient to inhibit PDE1B activity. The invention further provides a method for enhancing or potentiating dopamine D1 intracellular signaling activity in a cell or tissue comprising contacting said cell or tissue with an amount of a Compound of Formula II, in free or salt form, sufficient to inhibit PDE1 activity, e.g., PDE1A or PDE1B activity.
[0344] The invention also provides a method for treating a PDE1-related, especially PDE1B-related disorder, a dopamine D1 receptor intracellular signaling pathway disorder, or disorders that may be alleviated by the enhancement of the progesterone signaling pathway in a patient in need thereof comprising administering to the patient an effective amount of a Compound of the Invention, e.g., Formula I or any of any of 1.1-1.76, in that inhibits PDE1B, wherein PDE activity modulates phosphorylation of DARPP-32 and/or the GluR1 AMPA receptor. Similarly, the invention provides a method for treating a PDE 1-related, especially PDE1B-related disorder, a dopamine D1 receptor intracellular signaling pathway disorder, or disorders that may be alleviated by the enhancement of the progesterone signaling pathway in a patient in need thereof comprising administering to the patient an effective amount of a Compound of Formula II as hereinbefore described, in free or pharmaceutically acceptable salt form.
[0345] In another aspect, the invention also provides a method for the treatment for glaucoma or elevated intraocular pressure comprising topical administration of a therapeutically effective amount of a phospodiesterase type I (PDE1) Inhibitor of the Invention, in free or pharmaceutically acceptable salt form, in an opthalmically compatible carrier to the eye of a patient in need thereof. However, treatment may alternatively include a systemic therapy. Systemic therapy includes treatment that can directly reach the bloodstream, or oral methods of administration, for example.
[0346] The invention further provides a pharmaceutical composition for topical ophthalmic use comprising a PDE 1 inhibitor; for example an ophthalmic solution, suspension, cream or ointment comprising a PDE 1 Inhibitor of the Invention, in free or ophthamalogically acceptable salt form, in combination or association with an ophthamologically acceptable diluent or carrier.
[0347] Optionally, the PDE1 inhibitor may be administered sequentially or simultaneously with a second drug useful for treatment of glaucoma or elevated intraocular pressure. Where two active agents are administered, the therapeutically effective amount of each agent may be below the amount needed for activity as monotherapy. Accordingly, a subthreshold amount (i.e., an amount below the level necessary for efficacy as monotherapy) may be considered therapeutically effective and also may also be referred alternatively as an effective amount. Indeed, an advantage of administering different agents with different mechanisms of action and different side effect profiles may be to reduce the dosage and side effects of either or both agents, as well as to enhance or potentiate their activity as monotherapy.
[0348] The invention thus provides the method of treatment of a condition selected from glaucoma and elevated intraocular pressure comprising administering to a patient in need thereof an effective amount, e.g., a subthreshold amount, of an agent known to lower intraocular pressure concomitantly, simultaneously or sequentially with an effective amount, e.g., a subthreshold amount, of a PDE1 Inhibitor of the Invention, in free or pharmaceutically acceptable salt form, such that amount of the agent known to lower intraocular pressure and the amount of the PDE1 inhibitor in combination are effective to treat the condition.
[0349] In one embodiment, one or both of the agents are administered topically to the eye. Thus the invention provides a method of reducing the side effects of treatment of glaucoma or elevated intraocular pressure by administering a reduced dose of an agent known to lower intraocular pressure concomitantly, simultaneously or sequentially with an effective amount of a PDE1 inhibitor. However, methods other than topical administration, such as systemic therapeutic administration, may also be utilized.
[0350] The optional additional agent or agents for use in combination with a PDE1 inhibitor may, for example, be selected from the existing drugs comprise typically of instillation of a prostaglandin, pilocarpine, epinephrine, or topical beta-blocker treatment, e.g. with timolol, as well as systemically administered inhibitors of carbonic anhydrase, e.g. acetazolamide. Cholinesterase inhibitors such as physostigmine and echothiopate may also be employed and have an effect similar to that of pilocarpine. Drugs currently used to treat glaucoma thus include, e.g.,
1. Prostaglandin analogs such as latanoprost (Xalatan), bimatoprost (Lumigan) and travoprost (Travatan), which increase uveoscleral outflow of aqueous humor. Bimatoprost also increases trabecular outflow. 2. Topical beta-adrenergic receptor antagonists such as timolol, levobunolol (Betagan), and betaxolol, which decrease aqueous humor production by the ciliary body. 3. Alpha 2 -adrenergic agonists such as brimonidine (Alphagan), which work by a dual mechanism, decreasing aqueous production and increasing uveo-scleral outflow. 4. Less-selective sympathomimetics like epinephrine and dipivefrin (Propine) increase outflow of aqueous humor through trabecular meshwork and possibly through uveoscleral outflow pathway, probably by a beta 2 -agonist action. 5. Miotic agents (parasympathomimetics) like pilocarpine work by contraction of the ciliary muscle, tightening the trabecular meshwork and allowing increased outflow of the aqueous humour. 6. Carbonic anhydrase inhibitors like dorzolamide (Trusopt), brinzolamide (Azopt), acetazolamide (Diamox) lower secretion of aqueous humor by inhibiting carbonic anhydrase in the ciliary body. 7. Physostigmine is also used to treat glaucoma and delayed gastric emptying.
[0358] For example, the invention provides pharmaceutical compositions comprising a PDE1 Inhibitor of the Invention and an agent selected from (i) the prostanoids, unoprostone, latanoprost, travoprost, or bimatoprost; (ii) an alpha adrenergic agonist such as brimonidine, apraclonidine, or dipivefrin and (iii) a muscarinic agonist, such as pilocarpine. For example, the invention provides ophthalmic formulations comprising a PDE-1 Inhibitor of the Invention together with bimatoprost, abrimonidine, brimonidine, timolol, or combinations thereof, in free or ophthamalogically acceptable salt form, in combination or association with an ophthamologically acceptable diluent or carrier. In addition to selecting a combination, however, a person of ordinary skill in the art can select an appropriate selective receptor subtype agonist or antagonist. For example, for alpha adrenergic agonist, one can select an agonist selective for an alpha 1 adrenergic receptor, or an agonist selective for an alpha 2 adrenergic receptor such as brimonidine, for example. For a beta-adrenergic receptor antagonist, one can select an antagonist selective for either β 1 , or β2, or β 3 , depending on the appropriate therapeutic application. One can also select a muscarinic agonist selective for a particular receptor subtype such as M 1 -M 5 .
[0359] The PDE 1 inhibitor may be administered in the form of an ophthalmic composition, which includes an ophthalmic solution, cream or ointment. The ophthalmic composition may additionally include an intraocular-pressure lowering agent.
[0360] In yet another example, the PDE-1 Inhibitors disclosed may be combined with a subthreshold amount of an intraocular pressure-lowering agent which may be a bimatoprost ophthalmic solution, a brimonidine tartrate ophthalmic solution, or brimonidine tartrate/timolol maleate ophthalmic solution.
[0361] In addition to the above-mentioned methods, it has also been surprisingly discovered that PDE1 inhibitors are useful to treat psychosis, for example, any conditions characterized by psychotic symptoms such as hallucinations, paranoid or bizarre delusions, or disorganized speech and thinking, e.g., schizophrenia, schizoaffective disorder, schizophreniform disorder, psychotic disorder, delusional disorder, and mania, such as in acute manic episodes and bipolar disorder. Without intending to be bound by any theory, it is believed that typical and atypical antipsychotic drugs such as clozapine primarily have their antagonistic activity at the dopamine D2 receptor. PDE1 inhibitors, however, primarily act to enhance signaling at the dopamine D1 receptor. By enhancing D1 receptor signaling, PDE1 inhibitors can increase NMDA receptor function in various brain regions, for example in nucleus accumbens neurons and in the prefrontal cortex. This enhancement of function may be seen for example in NMDA receptors containing the NR2B subunit, and may occur e.g., via activation of the Src and protein kinase A family of kinases.
[0362] Therefore, the invention provides a new method for the treatment of psychosis, e.g., schizophrenia, schizoaffective disorder, schizophreniform disorder, psychotic disorder, delusional disorder, and mania, such as in acute manic episodes and bipolar disorder, comprising administering a therapeutically effective amount of a phosphodiesterase-1 (PDE 1) Inhibitor of the Invention, in free or pharmaceutically acceptable salt form, to a patient in need thereof.
[0363] PDE 1 Inhibitors may be used in the foregoing methods of treatment prophylaxis as a sole therapeutic agent, but may also be used in combination or for co-administration with other active agents. Thus, the invention further comprises a method of treating psychosis, e.g., schizophrenia, schizoaffective disorder, schizophreniform disorder, psychotic disorder, delusional disorder, or mania, comprising administering simultaneously, sequentially, or contemporaneously administering therapeutically effective amounts of:
(i) a PDE 1 Inhibitor of the invention, in free or pharmaceutically acceptable salt form; and (ii) an antipsychotic, e.g.,
Typical antipsychotics, e.g.,
Butyrophenones, e.g. Haloperidol (Haldol, Serenace), Droperidol (Droleptan); Phenothiazines, e.g., Chlorpromazine (Thorazine, Largactil), Fluphenazine (Prolixin), Perphenazine (Trilafon), Prochlorperazine (Compazine), Thioridazine (Mellaril, Melleril), Trifluoperazine (Stelazine), Mesoridazine, Periciazine, Promazine, Triflupromazine (Vesprin), Levomepromazine (Nozinan), Promethazine (Phenergan), Pimozide (Orap); Thioxanthenes, e.g., Chlorprothixene, Flupenthixol (Depixol, Fluanxol), Thiothixene (Navane), Zuclopenthixol (Clopixol, Acuphase);
Atypical antipsychotics, e.g.,
Clozapine (Clozaril), Olanzapine (Zyprexa), Risperidone (Risperdal), Quetiapine (Seroquel), Ziprasidone (Geodon), Amisulpride (Solian), Paliperidone (Invega), Aripiprazole (Abilify), Bifeprunox; norclozapine,
in free or pharmaceutically acceptable salt form, to a patient in need thereof.
[0373] In a particular embodiment, the Compounds of the Invention are particularly useful for the treatment or prophylaxis of schizophrenia.
[0374] Compounds of the Invention, in free or pharmaceutically acceptable salt form, are particularly useful for the treatment of Parkinson's disease, schizophrenia, narcolepsy, glaucoma and female sexual dysfunction.
[0375] In still another aspect, the invention provides a method of lengthening or enhancing growth of the eyelashes by administering an effective amount of a prostaglandin analogue, e.g., bimatoprost, concomitantly, simultaneously or sequentially with an effective amount of a PDE 1 inhibitor of the Invention, in free or pharmaceutically acceptable salt form, to the eye of a patient in need thereof.
[0376] In yet another aspect, the invention provides a method for the treatment or prophylaxis of traumatic brain injury comprising administering a therapeutically effective amount of a PDE1 inhibitor of the invention, in free or pharmaceutically acceptable salt form, to a patient in need thereof. Traumatic brain injury (TBI) encompasses primary injury as well as secondary injury, including both focal and diffuse brain injuries. Secondary injuries are multiple, parallel, interacting and interdependent cascades of biological reactions arising from discrete subcellular processes (e.g., toxicity due to reactive oxygen species, overstimulation of glutamate receptors, excessive influx of calcium and inflammatory upregulation) which are caused or exacerbated by the inflammatory response and progress after the initial (primary) injury. Abnormal calcium homeostasis is believed to be a critical component of the progression of secondary injury in both grey and white matter. For a review of TBI, see Park et al., CMAJ (2008) 178(9):1163-1170, the contents of which are incorporated herein in their entirety. Studies have shown that the cAMP-PKA signaling cascade is downregulated after TBI and treatment of PDE IV inhibitors such as rolipram to raise or restore cAMP level improves histopathological outcome and decreases inflammation after TBI. As Compounds of the present invention is a PDE1 inhibitor, it is believed that these compounds are also useful for the treatment of TBI, e.g., by restoring cAMP level and/or calcium homeostasis after traumatic brain injury.
[0377] The present invention also provides
(i) a Compound of the Invention, e.g., Formula I or any of any of 1.1-1.76, or Formula II as hereinbefore described in free, pharmaceutically acceptable salt or prodrug form for example for use in any method or in the treatment of any disease or condition as hereinbefore set forth, (ii) the use of a Compound of the Invention, e.g., Formula I or any of 1.1-1.76, or Formula II as hereinbefore described, in free, pharmaceutically acceptable salt or prodrug form, in the manufacture of a medicament for treating any disease or condition as hereinbefore set forth, (iii) a pharmaceutical composition comprising a Compound of the Invention, e.g., Formula I or any of 1.1-1.76, or Formula II as hereinbefore described, in free, pharmaceutically acceptable salt or prodrug form, in combination or association with a pharmaceutically acceptable diluent or carrier, and (iv) a pharmaceutical composition comprising a Compound of the Invention, e.g., Formula I or any of 1.1-1.76, or Formula II as hereinbefore described, in free, pharmaceutically acceptable salt or prodrug form, in combination or association with a pharmaceutically acceptable diluent or carrier for use in the treatment of any disease or condition as hereinbefore set forth.
[0382] Therefore, the invention provides use of a Compound of the Invention, e.g., Formula I or any of 1.1-1.76, or Formula II as hereinbefore described, in free, pharmaceutically acceptable salt or prodrug form, or a Compound of the Invention in a pharmaceutical composition form, for the manufacture of a medicament for the treatment or prophylactic treatment of the following diseases: Parkinson's disease, restless leg, tremors, dyskinesias, Huntington's disease, Alzheimer's disease, and drug-induced movement disorders; depression, attention deficit disorder, attention deficit hyperactivity disorder, bipolar illness, anxiety, sleep disorder, narcolepsy, cognitive impairment, dementia, Tourette's syndrome, autism, fragile X syndrome, psychostimulant withdrawal, and/or drug addiction; cerebrovascular disease, stroke, congestive heart disease, hypertension, pulmonary hypertension, and/or sexual dysfunction; asthma, chronic obstructive pulmonary disease, and/or allergic rhinitis, as well as autoimmune and inflammatory diseases; and/or female sexual dysfunction, exercise amenorrhoea, anovulation, menopause, menopausal symptoms, hypothyroidism, pre-menstrual syndrome, premature labor, infertility, irregular menstrual cycles, abnormal uterine bleeding, osteoporosis, multiple sclerosis, prostate enlargement, prostate cancer, hypothyroidism, estrogen-induced endometrial hyperplasia or carcinoma; and/or any disease or condition characterized by low levels of cAMP and/or cGMP (or inhibition of cAMP and/or cGMP signaling pathways) in cells expressing PDE1, and/or by reduced dopamine D1 receptor signaling activity; and/or any disease or condition that may be ameliorated by the enhancement of progesterone signaling.
[0383] The invention also provides use of a Compound of the Invention, in free or pharmaceutically acceptable salt form, for the manufacture of a medicament for the treatment or prophylactic treatment of:
a) glaucoma or elevated intraocular pressure, b) psychosis, for example, any conditions characterized by psychotic symptoms such as hallucinations, paranoid or bizarre delusions, or disorganized speech and thinking, e.g., schizophrenia, schizoaffective disorder, schizophreniform disorder, psychotic disorder, delusional disorder, and mania, such as in acute manic episodes and bipolar disorder, c) traumatic brain injury.
[0387] The phrase “Compounds of the Invention” or “PDE 1 inhibitors of the Invention” encompasses any and all of the compounds disclosed herewith, e.g., a Compound of Formula I or any of 1.1-1.76, or Formula II as hereinbefore described, in free or salt form.
[0388] The words “treatment” and “treating” are to be understood accordingly as embracing prophylaxis and treatment or amelioration of symptoms of disease as well as treatment of the cause of the disease.
[0389] For methods of treatment, the word “effective amount” is intended to encompass a therapeutically effective amount to treat a specific disease or disorder.
[0390] The term “pulmonary hypertension” is intended to encompass pulmonary arterial hypertension.
[0391] The term “patient” include human or non-human (i.e., animal) patient. In particular embodiment, the invention encompasses both human and nonhuman. In another embodiment, the invention encompasses nonhuman. In other embodiment, the term encompasses human.
[0392] The term “comprising” as used in this disclosure is intended to be open-ended and does not exclude additional, unrecited elements or method steps.
[0393] Compounds of the Invention are in particular useful for the treatment of Parkinson's disease, narcolepsy and female sexual dysfunction.
[0394] Compounds of the Invention, e.g., Formula I or any of 1.1-1.76, or Formula II as hereinbefore described, in free or pharmaceutically acceptable salt form may be used as a sole therapeutic agent, but may also be used in combination or for co-administration with other active agents. For example, as Compounds of the Invention potentiate the activity of D1 agonists, such as dopamine, they may be simultaneously, sequentially, or contemporaneously administered with conventional dopaminergic medications, such as levodopa and levodopa adjuncts (carbidopa, COMT inhibitors, MAO-B inhibitors), dopamine agonists, and anticholinergics, e.g., in the treatment of a patient having Parkinson's disease. In addition, the novel PDE 1 inhibitors, e.g., as described herein, may also be administered in combination with estrogen/estradiollestriol and/or progesterone/progestins to enhance the effectiveness of hormone replacement therapy or treatment of estrogen-induced endometrial hyperplasia or carcinoma.
[0395] Dosages employed in practicing the present invention will of course vary depending, e.g. on the particular disease or condition to be treated, the particular Compound of the Invention used, the mode of administration, and the therapy desired. Compounds of the Invention may be administered by any suitable route, including orally, parenterally, transdermally, or by inhalation, but are preferably administered orally. In general, satisfactory results, e.g. for the treatment of diseases as hereinbefore set forth are indicated to be obtained on oral administration at dosages of the order from about 0.01 to 2.0 mg/kg. In larger mammals, for example humans, an indicated daily dosage for oral administration will accordingly be in the range of from about 0.75 to 150 mg, conveniently administered once, or in divided doses 2 to 4 times, daily or in sustained release form. Unit dosage forms for oral administration thus for example may comprise from about 0.2 to 75 or 150 mg, e.g. from about 0.2 or 2.0 to 50, 75 or 100 mg of a Compound of the Invention, together with a pharmaceutically acceptable diluent or carrier therefor.
[0396] Pharmaceutical compositions comprising Compounds of the Invention may be prepared using conventional diluents or excipients and techniques known in the galenic art. Thus oral dosage forms may include tablets, capsules, solutions, suspensions and the like.
EXAMPLES
[0397] The synthetic methods for various Compounds of the Present Invention are illustrated below. Other compounds of the Invention and their salts may be made using the methods as similarly described below and/or by methods similar to those generally described in the detailed description and by methods known in the chemical art.
Example 1
(6aR,9aS)-5,6a,7,8,9,9a-hexahydro-5-methyl-3-(phenylthio)-2-(4-(6-fluoropyridin-2-yl)benzyl)-cyclopent[4,5]imidazo[1,2-a]pyrazolo[4,3-e]pyrimidin-4(2H)-one
[0398]
[0399] (6aR,9aS)-5,6a,7,8,9,9a-hexahydro-5-methyl-2-(4-(6-fluoropyridin-2-yl)benzyl)-cyclopent[4,5]imidazo[1,2-a]pyrazolo[4,3-e]pyrimidin-4(2H)-one (56.8 mg, 0.136 mmol) and phenyl disulfide (59.6 mg, 0.273 mmol) are dissolved in 1 mL of anhydrous THF, and then 273 uL of 1.0 M LiHMDS in THF is added dropwise. The reaction mixture is stirred at room temperature for an hour, and then quenched with saline. The mixture is separated with a semi-preparative HPLC to give 27 mg of pure product as yellow solids. MS (ESI) m/z 525.2 [M+H] + .
Example 2
(6aR,9aS)-5,6a,7,8,9,9a-hexahydro-5-methyl-3-(phenylsulfinyl)-2-(4-(6-fluoropyridin-2-yl)benzyl)-cyclopent[4,5]imidazo[1,2-a]pyrazolo[4,3-e]pyrimidin-4(2H)-one
[0400]
[0401] (6aR,9aS)-5,6a,7,8,9,9a-hexahydro-5-methyl-3-(phenylthio)-2-(4-(6-fluoropyridin-2-yl)benzyl)-cyclopent[4,5]imidazo[1,2-a]pyrazolo[4,3-e]pyrimidin-4(2H)-one (12 mg, 0.023 mmol) is dissolved in CH 3 CN (2 mL) and CH 3 OH (2 mL), and then an aqueous solution of oxone is added. The reaction mixture is stirred at room temperature for a week, and then purified by a semi-preparative HPLC to give pure product as white solids. MS (ESI) m/z 541.2 [M+H] + .
Example 3
(6aR,9aS)-5,6a,7,8,9,9a-hexahydro-5-methyl-3-(methylthio)-2-(4-(6-fluoropyridin-2-yl)benzyl)-cyclopent[4,5]imidazo[1,2-a]pyrazolo[4,3-e]pyrimidin-4(2H)-one
[0402]
[0403] (6aR,9aS)-5,6a,7,8,9,9a-hexahydro-5-methyl-2-(4-(6-fluoropyridin-2-yl)benzyl)-cyclopent[4,5]imidazo[1,2-a]pyrazolo[4,3-e]pyrimidin-4(2H)-one (50 mg, 0.12 mmol) and methyl disulfide (21.3 μL, 0.24 mmol) are dissolved in 1 mL of anhydrous THF, and then 360 uL of 1.0 M LDA in THF is added dropwise. The reaction mixture is stirred at room temperature for an hour, and then quenched with saline. The mixture is separated with a semi-preparative HPLC to give 6.8 mg of pure product as pale yellow solids. MS (ESI) m/z 463.2 [M+H] + .
Example 4
(6aR,9aS)-5,6a,7,8,9,9a-hexahydro-3-(methylthio)-2-(4-(6-fluoropyridin-2-yl)benzyl)-cyclopent[4,5]imidazo[1,2-a]pyrazolo[4,3-e]pyrimidin-4(2H)-one
[0404]
[0405] (6aR,9aS)-5,6a,7,8,9,9a-hexahydro-5-methyl-3-(methylthio)-2-(4-(6-fluoropyridin-2-yl)benzyl)-cyclopent[4,5]imidazo[1,2-a]pyrazolo[4,3-e]pyrimidin-4(2H)-one (25 mg, 0.054 mmol) and P 4 S 10 (48.1 mg, 0.108 mmol) are placed in a Biotage microwave vial, and then 1.0 mL of 7N ammonia in MeOH is added. The sealed vial is heated in a Biotage microwave at 150° C. for 6 h. After solvent is removed, the residue is suspended in DMF, and then filtered. The obtained filtrate is purified by a semi-preparative HPLC to give 10.6 mg of pure product as pale yellow solids (yield: 44%). MS (ESI) m/z 449.2 [M+H] + .
Example 5
(6aR,9aS)-5,6a,7,8,9,9a-hexahydro-3-(pyridin-2-ylthio)-2-(4-(6-fluoropyridin-2-yl)benzyl)-cyclopent[4,5]imidazo[1,2-a]pyrazolo[4,3-e]pyrimidin-4(2H)-one
[0406]
[0407] The synthetic procedure of this compound is analogous to EXAMPLE 1 wherein 2-pyridyl disulfide is used instead of phenyl disulfide. MS (ESI) m/z 526.2 [M+H] + .
Example 6
(6aR,9aS)-5,6a,7,8,9,9a-hexahydro-5-methyl-3-((R)-methylsulfinyl)-2-(4-(6-fluoropyridin-2-yl)benzyl)-cyclopent[4,5]imidazo[1,2-a]pyrazolo[4,3-e]pyrimidin-4(2H)-one
[0408]
[0409] (6aR,9aS)-5,6a,7,8,9,9a-hexahydro-5-methyl-3-(methylthio)-2-(4-(6-fluoropyridin-2-yl)benzyl)-cyclopent[4,5]imidazo[1,2-a]pyrazolo[4,3-e]pyrimidin-4(2H)-one (35.2 mg, 0.076 mmol) is dissolved in CH 3 CN (0.5 mL) and CH 3 OH (2 mL), and then an aqueous solution of oxone (93.7 mg, 0.152 mmol) is added. The reaction mixture is stirred at room temperature for 20 h, and then purified by a semi-preparative HPLC to give pure product as white solids. MS (ESI) m/z 479.2 [M+H] + .
Example 7
(6aR,9aS)-5,6a,7,8,9,9a-hexahydro-5-methyl-3-((S)-methylsulfinyl)-2-(4-(6-fluoropyridin-2-yl)benzyl)-cyclopent[4,5]imidazo[1,2-a]pyrazolo[4,3-e]pyrimidin-4(2H)-one
[0410]
[0411] The synthetic procedure of this compound is the same as EXAMPLE 6. A pair of diastereoisomers is obtained during the synthesis. Both diastereoisomers can be separated using an achiral reversed-phase HPLC column. Product is obtained as white solids. MS (ESI) m/z 479.2 [M+H] + .
Example 8
(6aR,9aS)-5,6a,7,8,9,9a-hexahydro-5-methyl-3-(methylsulfonyl)-2-(4-(6-fluoropyridin-2-yl)benzyl)-cyclopent[4,5]imidazo[1,2-a]pyrazolo[4,3-e]pyrimidin-4(2H)-one
[0412]
[0413] (6aR,9aS)-5,6a,7,8,9,9a-hexahydro-5-methyl-3-(methylthio)-2-(4-(6-fluoropyridin-2-yl)benzyl)-cyclopent[4,5]imidazo[1,2-a]pyrazolo[4,3-e]pyrimidin-4(2H)-one (35.2 mg, 0.076 mmol) is dissolved in CH 3 CN (0.5 mL) and CH 3 OH (2 mL), and then an aqueous solution of oxone (139 mg, 0.226 mmol) is added. The reaction mixture is stirred at room temperature for 2 days, and then purified by a semi-preparative HPLC to give pure product as white solids. MS (ESI) m/z 495.2 [M+H] + .
Example 9
Measurement of PDE1B Inhibition In Vitro Using IMAP Phosphodiesterase Assay Kit
[0414] Phosphodiesterase 1B (PDE 1B) is a calcium/calmodulin dependent phosphodiesterase enzyme that converts cyclic guanosine monophosphate (cGMP) to 5′-guanosine monophosphate (5′-GMP). PDE1B can also convert a modified cGMP substrate, such as the fluorescent molecule cGMP-fluorescein, to the corresponding GMP-fluorescein. The generation of GMP-fluorescein from cGMP-fluorescein can be quantitated, using, for example, the IMAP (Molecular Devices, Sunnyvale, Calif.) immobilized-metal affinity particle reagent.
[0415] Briefly, the IMAP reagent binds with high affinity to the free 5′-phosphate that is found in GMP-fluorescein and not in cGMP-fluorescein. The resulting GMP-fluorescein-IMAP complex is large relative to cGMP-fluorescein. Small fluorophores that are bound up in a large, slowly tumbling, complex can be distinguished from unbound fluorophores, because the photons emitted as they fluoresce retain the same polarity as the photons used to excite the fluorescence.
[0416] In the phosphodiesterase assay, cGMP-fluorescein, which cannot be bound to IMAP, and therefore retains little fluorescence polarization, is converted to GMP-fluorescein, which, when bound to IMAP, yields a large increase in fluorescence polarization (Δmp). Inhibition of phosphodiesterase, therefore, is detected as a decrease in Δmp.
[0417] Enzyme Assay
[0000] Materials: All chemicals are available from Sigma-Aldrich (St. Louis, Mo.) except for IMAP reagents (reaction buffer, binding buffer, FL-GMP and IMAP beads), which are available from Molecular Devices (Sunnyvale, Calif.).
Assay: 3′,5′-cyclic-nucleotide-specific bovine brain phosphodiesterase (Sigma, St. Louis, Mo.) is reconstituted with 50% glycerol to 2.5 U/ml. One unit of enzyme will hydrolyze 1.0 μmole of 3′,5′-cAMP to 5′-AMP per min at pH 7.5 at 30° C. One part enzyme is added to 1999 parts reaction buffer (30 μM CaCl 2 , 10 U/ml of calmodulin (Sigma P2277), 10 mM Tris-HCl pH 7.2, 10 mM MgCl 2 , 0.1% BSA, 0.05% NaN 3 ) to yield a final concentration of 1.25 mU/ml. 99 μl of diluted enzyme solution is added into each well in a flat bottom 96-well polystyrene plate to which 1 μl of test compound dissolved in 100% DMSO is added. The compounds are mixed and pre-incubated with the enzyme for 10 min at room temperature.
[0418] The FL-GMP conversion reaction is initiated by combining 4 parts enzyme and inhibitor mix with 1 part substrate solution (0.225 μM) in a 384-well microtiter plate. The reaction is incubated in dark at room temperature for 15 min. The reaction is halted by addition of 60 μl of binding reagent (1:400 dilution of IMAP beads in binding buffer supplemented with 1:1800 dilution of antifoam) to each well of the 384-well plate. The plate is incubated at room temperature for 1 hour to allow IMAP binding to proceed to completion, and then placed in an Envision multimode microplate reader (PerkinElmer, Shelton, Conn.) to measure the fluorescence polarization (Δmp).
[0419] A decrease in GMP concentration, measured as decreased Amp, is indicative of inhibition of PDE activity. IC 50 values are determined by measuring enzyme activity in the presence of 8 to 16 concentrations of compound ranging from 0.0037 nM to 80,000 nM and then plotting drug concentration versus ΔmP, which allows IC 50 values to be estimated using nonlinear regression software (XLFit; IDBS, Cambridge, Mass.).
[0420] The Compounds of the Invention may be selected and tested in an assay as described or similarly described herein for PDE1 inhibitory activity. The exemplified compounds of the invention generally have IC 50 values of less than 1 μM, e.g., some less than 250 nM, some less than 10 nM, some less than 5 nM, e.g., the Compounds of Examples 1, 2 and 3 generally have IC 50 values of less than 250 nM.
Example 10
PDE1 Inhibitor Effect on Sexual Response in Female Rats
[0421] The effect of PDE1 inhibitors on Lordosis Response in female rats may be measured as described in Mani, et al., Science (2000) 287: 1053. Ovariectomized and cannulated wild-type rats are primed with 2 μg estrogen followed 24 hours later by intracerebroventricular (icy) injection of progesterone (2 μg), PDE1 inhibitors of the present invention (0.1 mg, 1.0 mg or 2.5 mg) or sesame oil vehicle (control). The rats are tested for lordosis response in the presence of male rats. Lordosis response is quantified by the lordosis quotient (LQ=number of lordosis/10 mounts×100). | Optionally substituted 3-(thio, sulfinyl or sulfonyl)-7,8-dihydro-(1H or 2H)-imidazo[1,2-a]pyrazolo[4,3-e]pyrimidin-4(5H)-one or a substituted 3-(thio, sulfinyl or sulfonyl)-7,8,9-trihydro-(1H or 2H)-pyrimido[1,2-a]pyrazolo[4,3-e]pyrimidin-4(5H)-one compounds or Compounds of Formula (I), processes for their production, their use as pharmaceuticals and pharmaceutical compositions comprising them. | 0 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent application Ser. No. 09/455,628, filed Dec. 7, 1999, which is assigned to the same assignee as the present application, is incorporated herein by reference and is a continuation of U.S. patent application Ser. No. 08/557,147, filed Apr. 19, 1996, now U.S. Pat. No. 6,011,976, which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] This invention relates to a telecommunications system. In particular, but not exclusively, it relates to a mobile communications system such as a cellular mobile radio or telephone system.
[0003] A recent innovation in such systems has been the introduction of Subscriber Identity Modules (SIM cards). These are integrated circuit cards which can be releasably inserted into a mobile telephone and which contain in memory the subscriber's identity, i.e., his telephone number. These known SIM cards also have a rolling buffer which can store a certain number of alphanumeric characters. The buffer facilitates the so-called Short Message Service (SMS) in which a message for a subscriber or for a specified group of subscribers can be broadcast over the air, as an advanced form of radiopaging. Messages can be received by a mobile telephone whenever it is idle or on stand-by. However, if a message is received which would overfill the buffer, data is lost on a first-in-first-out basis.
[0004] It is an object of the invention to provide a more efficient and remotely reconfigurable SIM card.
SUMMARY OF THE INVENTION
[0005] From one aspect, the present invention consists in a telecommunications system comprising at least one host station and a plurality of subscriber units, the or each host station being operable to transmit a message to at least one of the subscriber units, and each subscriber unit having a multiplicity of fixed memory locations and means responsive to the detection of the message to store the message in a selected one of the fixed memory locations which can not be overwritten from the subscriber unit, but which can be accessed from the subscriber unit when required.
[0006] In the present application, a “fixed” memory location means a location into which data can be written, and excludes first-in-first-out or circular buffers. Overwriting of all the data in certain “fixed” memory locations may occur in contrast to the first-in-first-out loss of data experienced with current SMS buffers.
[0007] Thus, for example, a set of telephone numbers, each with an identifying alphanumeric tag, can be transmitted to the SIM card, allowing users easy access to commonly used services such as hotels, car hire or airline reservations. This feature is known as a Value Added Service Directory.
[0008] A message may be retrievable by the subscriber on the entry of simple, short codes into the subscriber unit, each memory location corresponding to a particular code. A message may include a telephone number and, once stored, may be able to be overwritten over the air. Preferably, the or each host station is operable to transmit a request for information stored in a subscriber unit. The information may be included in a message and it may also include information which is stored in a secure memory location, accessible only when the subscriber enters a personal identification number (PIN number). The information may include credit details relevant to the subscriber, for example, a credit card number of credit status, thus greatly facilitating credit card transactions carried out over the telephone. Using this feature of the invention, a credit account holder avoids having to dictate his account details and need only enter the mandatory PIN number.
[0009] The host station may be operable to transmit instructions to lock and/or unlock a memory location at the subscriber unit. It may be operable to transmit instructions to run a program stored in memory locations at the subscriber unit. The host station may be operable to transmit files containing functional data and/or files containing non-functional data to the subscriber unit. The messages, requests for information and the instructions being transmitted may be in a specific format which the subscriber unit is able to distinguish from other formats. The specific format may be made secure against interception.
[0010] In a preferred embodiment, the subscriber unit comprises a mobile radio or telephone and an integrated circuit card which can be removably connected to the radio/telephone. The integrated circuit card may contain the memory locations and may contain means for distinguishing the specific format from other formats. The card may contain means for distinguishing between the messages, requests for information and instructions. The card may also contain the means for storing the messages and means for acting on the requests and instructions.
[0011] From another aspect, the invention consists in a module for controlling a subscriber unit in a telecommunications system, comprising a multiplicity of fixed memory locations and means responsive to the detection of a message transmitted remotely thereto to store the message in a selected one of the fixed memory locations, and being adapted for removable connection to a transceiver of the subscriber unit.
[0012] At least one of the fixed memory locations may be protected from overwriting by the subscriber. The module or card may include means for rendering any or all of said fixed memory locations accessible or inaccessible by either the subscriber or the host station. The card may include a directory structure within which files can be stored.
[0013] The invention is particularly applicable to global telecommunication systems in which the mobile cellular telephone networks of various countries or areas communicate using a common standard. An example of such a global system is GSM (Global System for Mobile Communications) currently operating in Europe. However the invention is not limited to global systems and could be applied to a single national cellular network or even to a fixed land-linked network.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] An embodiment of the invention will now be described by way of example with reference to the accompanying drawings in which:
[0015] FIG. 1 shows the transmission of messages to a subscriber unit in a system according to the invention;
[0016] FIG. 2 shows a process in which a subscriber unit transmits a message and requested information;
[0017] FIG. 3 is a block diagram showing elements of a module shown in FIGS. 1 and 2 ;
[0018] FIG. 4 shows details of one of the blocks shown in FIG. 3 ; and
[0019] FIG. 5 is a flowchart showing the operation of the module shown in FIGS. 1 to 4 .
DETAILED DESCRIPTION OF THE INVENTION
[0020] FIG. 1 illustrates an SMS distribution path according to the invention. In the prior art, the short messages have usually been directed to a single subscriber or a specified group of subscribers such as a sales team.
[0021] However, GSM also supports a feature known as Cell Broadcast in which messages can be sent to all the subscribers in a particular area. In the embodiment of the invention illustrated, a message consists of the telephone number of an advertiser and an alphanumeric tag to identify the advertiser.
[0022] An operator enters the message into a terminal 1 . The message is then coded into a secure format known to applicants as an Embedded Command Stream (ECS) and sent via a modem 2 and a fixed line 3 to a local GSM switch 4 . According to its delivery address, the message is delivered to any or all of the other switches within that network, or even across networks.
[0023] The switch 4 , which in this example is in the geographical area to which the message is to be transmitted, delivers the message to a number of cellsites 5 . The cellsites 5 are the base transceiver stations of the GSM network.
[0024] Each cellsite 5 then broadcasts the message to a group of transceivers or mobile telephones, hereinafter referred to as “mobiles”. If Cell Broadcast is used, the group consists of all mobiles within the geographical area at the time of the broadcast.
[0025] A selected mobile 6 receiving the message transmits a confirmation of receipt back to its respective cellsite 5 . From now on, until an update situation, the system will not contact this mobile 6 again.
[0026] The mobile 6 recognizes the message as SMS data and passes it to a SIM card 7 , which is a small self-contained microprocessor, held in a slot in the mobile 6 . The SIM card 7 in turn recognizes the ECS using special hardware and software and stores the message in memory in such a way that it may not be overwritten by the subscriber. Known SIM cards contain a large number of fixed memory locations in which the subscriber can store frequently dialed numbers and corresponding alphanumeric tags. The SIM card 7 of the invention stores the message in one of these locations, and then carries out a write protect operation. The locations dedicated to storing write protected messages may be designated by code numbers relating to a particular category of advertiser. Thus, for example, car hire company telephone numbers can be stored in location 01 , hotel reservations in location 02 and so on.
[0027] FIG. 2 shows a call placing process in which a subscriber communicates with an advertiser. The subscriber, remembering that the car hire company's number is in location 01 as shown at 8 , keys in a short code corresponding to the location, such as 01 #. The mobile 6 then interrogates the SIM card 7 to retrieve the telephone number from the location. The SIM card 7 provides both the number and the alphanumeric tag giving the company's name and displays it to the subscriber. The user confirms that he wishes to proceed by pressing SEND.
[0028] Next, the mobile obtains a voice channel through which the call proceeds to the dialed number. The GSM system automatically handles intra-network and inter-network hops. At this point the subscriber can hold a voice conversation with the company.
[0029] Providing the correct equipment has been installed at the company, as soon as the call is answered, subscriber identity information read from the SIM card 7 gives the company immediate customer billing details such as a name and address.
[0030] The SIM card 7 also contains information detailing the subscriber's credit account. This information is held in a separate, secure memory location, accessible only when the subscriber enters a mandatory PIN number, known only to himself, thus confirming that the mobile has not been stolen or lost. When the subscriber has confirmed his car hire deal, he enters the PIN number into the mobile 6 , requesting the credit information from the SIM card 7 . The SIM card 7 supplies the information and the mobile uses existing voice/data techniques to transmit the information to the company, in a format secure against detection by fraudsters. The sale is confirmed by the company or its equipment and the call is terminated.
[0031] In this example, it is also possible to obtain a telephone or fax number from the operator-assisted directory enquiries system without the subscriber having to manually enter the number into the communications terminal which he desires to use.
[0032] To use this feature, the subscriber calls network directory enquiries and gives the name of the person, company or service of which he wishes to ascertain the telephone number, as well as any additional information requested by the operator answering the call. The operator then locates the number, confirms it and enquires as to whether the number is to be transmitted verbally, transferred over SMS into a given memory location of the subscriber's SIM card or both.
[0033] If the subscriber chooses a SIM update, the voice call is terminated and the operator initiates the SMS process by entering a sequence into a computer or pressing a dedicated button. The telephone number is then encoded into an ECS message at the despatch center and is posted across the network to the subscriber's communications terminal, which transmits a confirmation to the despatch center. Thus, the retry mechanism, which operates until such a confirmation is received, is suspended.
[0034] The communications terminal recognizes the message as SMS data, passes it to the SIM card, and if capable, displays a “message received” banner. The SIM card in turn recognizes the ECS using special hardware and software, and decodes it accordingly. The number, and any associated alphanumeric tag, which would normally consist of the name of the person or company, are recovered together with the memory location in which they are intended to be stored. The number and name-tag are then written to that location and are write-protected if requested by the subscriber, the overwrite protection being encoded into the message at source.
[0035] Subsequently, the subscriber attempts to place a call to the number in the known memory location by keying in the memory location number. The SIM card passes the telephone or fax number to the communications terminal on demand, and upon receipt of the subscriber's confirmation, the communications terminal sets up the call to the desired number.
[0036] FIG. 3 shows the electronic structure of the SIM card 7 . The card communicates with the mobile to which it is connected via an input/output (I/O) manager 15 , preferably using the protocol ISO 7816 T=0. A filter 16 receives incoming data from the I/O manager and detects any ECS messages from among the short messages received. The ECS messages are sent directly to an extended erasable read only memory (E 2 ROM) 17 , which is preferably a “flash” E 2 ROM. Data can also be output from the E 2 ROM directly to the I/O manager 15 . The remaining blocks shown in FIG. 3 are standard components of a SIM card.
[0037] FIG. 4 shows how the E 2 ROM is organized. A root directory 18 contains a SIM administration and identifier 19 , a GSM directory and network data 20 , and a telecom directory 21 .
[0038] The telecom directory in turn contains memory locations as follows: “abbreviated dial numbers” 22 , “capability configuration” 23 , “short messages” 24 , “fixed dial numbers” 25 , and “charging counter” 26 . Each block represents a plurality of memory locations. The frequently dialed numbers and corresponding alphanumeric tags are stored at locations 22 .
[0039] The “abbreviated dial numbers” locations 22 and the “short messages” locations 24 each have an associated locking control file 27 , 28 , respectively. The locking control files constitute means for read/write protecting and removing read/write protection from their associated memory locations. The locking control files 27 , 28 will typically be in the telecom directory 21 as shown, however they can be located elsewhere such as in an administration directory.
[0040] FIG. 5 is a flowchart illustrating the operation of the SIM card 7 , which uses the specially fabricated hardware and software which has been described above to implement the operations illustrated. At lozenge 9 , messages, requests, and instructions having ECS are distinguished from those without. Each of these ECS types consists of a data stream headed by a command which is one of at least four types: write commands for the messages, read commands for the requests for information, attribute commands for lock or unlock instructions and run commands for instructions to run a program.
[0041] The command and data types are decoded at box 10 and acted on in one of the four paths 11 - 14 .
[0042] Path 11 handles the write commands to store messages starting at a location specified therein. Path 12 handles the read commands; again, the requests for information contain a location to be accessed first. Successive locations are read and the data stored in a buffer until the required amount of data has been read. The data in the buffer is then encoded into the ECS format and despatched from the mobile using SMS to the calling party.
[0043] In path 13 , attribute commands are used to lock or unlock specified memory locations and render them accessible or inaccessible, either to calling parties or to the subscriber. In path 14 , run commands cause a program stored in the SIM card to be run.
[0044] The basic ECS system is expandable to up to 255 internal shell commands of which write, read, lock/unlock and run are four examples. The specific protocol used for the transfer of information is not fixed and could be ISO7816 T=0 or any other suitable protocol.
[0045] The internal shell commands are a supplement to the ability of the system to create external file objects within the SIM card 7 . The file objects are of two types: Application Data File Programs (ADFP's) containing functional data which can be executed by the SIM card processor and can self modify if required and Application Data Files (ADF's) containing non-functional data which does not have these capabilities. Existing ADF(P)'S can be modified over-the-air enabling advanced facilities such as personalization, re-personalization or downloadable phone book.
[0046] The SIM card 7 has a directory structure, similar to that of a computer disk, and new ADF(P)'S can be downloaded into any directory over the air. Also over the air, directories can be created, deleted and modified, multiple tree directory operations can be carried out and ADF(P)'S that are no longer required can be deleted. The amount of ADF(P) data which can be downloaded is limited only by the size of the E 2 ROM memory of the card.
[0047] The invention, as described, greatly extends the applications of SIM cards. For example, using the Value Added Services Directory, subscribers can book hotels and airline seats over their mobiles quickly and easily.
[0048] An additional advantage of this feature of the invention is that the geographical distribution of messages to cards in a specific area such as the South of France is facilitated. Thus advertisers can direct their messages to all mobile subscribers in the specific area. This, is particularly useful when subscribers “roam” from one area to another and have no knowledge of local services.
[0049] The directory enquiries download enables contact telephone or fax numbers to be delivered to a subscriber's communications terminal without any intervention by the subscriber. The process of manually entering a number whilst engaged in a call to the operator is often dangerous, especially when the subscriber is driving.
[0050] The ability of the system to download ADF(P)'S means that additional services can be added to the SIM card over the air while maintaining total compatibility with the existing cellular system. Thus the SIM card could acquire the functions of a credit card, passport, driving license, car park pass, membership card and so on, becoming a multi-service card. Also, dynamically updatable services can be added which require a different process to be run each time a service is accessed.
[0051] Once the card has extra services on it, it can be used outside of the mobile phone environment if desired as a standalone item. This can be read from or written to by a dedicated piece of hardware, such as a point of sale machine. If desired, the new services can be deleted, however the card will never lose its mobile phone SIM capability. In addition, if the card has extra services, they will continue to function even if the subscriber has been disconnected from the mobile phone network, unless otherwise desired.
[0052] Modifications are possible without departing from the scope of the invention. For example, the SIM card can be trained only to receive messages detailing services relevant to the subscriber's needs. | In a telecommunications system such as a global mobile telephone network in which each subscriber unit includes a Subscriber Identity Module (SIM card), each SIM card has fixed memory locations, to which data can be addressed over the air. Some of the locations can not be overwritten from the subscriber unit but can be accessed therefrom on the entry of short simple codes, each associated with one of the locations. Further fixed memory locations can be read over the air only when the subscriber enters a personal identification number. Locking control files are used to control read/write access to the locations respectively. | 7 |
PRIORITY
[0001] This application claims priority from a co-pending application entitled “Environmentally friendly solid lubricant sticks” filed by Michael J. Mitrovich on Dec. 5, 2005, having Ser. No. 11/295,711, which claimed priority from a provisional application entitled “Environmentally friendly solid lubricant sticks”, filed by Michael J. Mitrovich on Dec. 3, 2004, having Ser. No. 60/633,279. Application Ser. No. 11/295,711 claims priority of application entitled “Solid Lubricant and Composition” filed by Michael J. Mitrovich on Sep. 3, 2003, having Ser. No. 10/655,082 (now abandoned), which claimed priority from an application entitled “Solid Lubricant and Composition” filed by Michael J. Mitrovich on Apr. 11, 2002, having Ser. No. 10/123,001 (now U.S. Pat. No. 6,649,573), which itself claimed priority from a provisional application entitled “Solid Lubricant and Composition” filed by Michael J. Mitrovich filed on Apr. 13, 2001, having Ser. No. 60/283,869 (now abandoned), the disclosures of which are all incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] For over fifty years heavy haul railroads have used a variety of methods to reduce friction between the locomotive and railcar wheel flanges and the gauge face of the rail with which it comes in contact. Railroads and transits have realized they can save substantial amounts of money in lowered maintenance and equipment replacements if lubrication is applied. Several methods have been used including one method wherein hundreds of wayside lubricators eject hydrocarbon petroleum based lubricants onto the gauge face of the rail as the train travels through a curve. A second method for applying lubricant has been to use track inspection trucks to spray petroleum or synthetic grease onto the gauge face of the track at the inspection truck goes through a curve. A third method is to apply lubricant to the wheel flange of the locomotive whereupon the lubricant gets transferred from the wheel flange of the locomotive to the wheel flange of railcars. Lubricant is then passed back through the train as successive wheels come in contact with the rail and pick up some of the lubricant.
[0003] These types of lubrication are typically accomplished by spray devices that squirt small amounts of lubricating oil onto wheel flanges. There are inherent problems with the above-described methods of applying lubricant. First, sprayed oil has a tendency to migrate to the tread of the wheel, making it more difficult for the train to stop. Also, grease and oil on top of the rail can cause the train wheels to slip inhibiting the ability of the brakes of the train to slow or stop the train. In addition, grease and oil on top of the rail can make it difficult for the train to gain traction from a stopped position or when climbing an incline. Secondly, to keep oil spray devices in working order has required excessive maintenance time and expense.
[0004] An alternative method for overcoming problems with spraying oil onto the wheel flange of the locomotive or railcar has been to use a solid lubricant stick or rod. The stick or rod is inserted into a tube that is then applied by various mechanical means to the flanges of the wheel of a locomotive or railcar.
[0005] Prior art solid lubricants also have several inherent problems. First, prior art lubricant sticks contain graphite or molybdenum powders because of their anti-wear properties. These prior art molybdenum disulfide compound sticks were made without polymers whereby the molybdenum disulfide was smashed together in a foil wrapper. However, this made the lubricant stick very hard and brittle, so that they could not withstand a rugged locomotive or railcar environment and the sticks would break or disappear.
[0006] Prior art solid lubricant stick compositions also have used polymeric carriers to provide durability, but have also included materials that do not provide extreme pressure anti-wear protection or are potentially hazardous to the environment. In some prior art, the sticks have promoted the ability to lubricate a particular wheel flange, but because they have not contained additives to withstand the extreme pressure of a locomotive or railcar flange against the track, the lubricant has not transferred throughout the train. In other prior art, the solid lubricant has lubricated throughout the train, but these formulas contain undesirable hazardous metallic powders, because of their anti-wear capabilities, but the metallic powders not only pollute the environment, but also may be hazardous to railroad workers.
[0007] U.S. Pat. No. 3,537,819 to Davis et al., discloses that the characteristics of the solid lubricant such as hardness, deposition and rigidity are dependant on the molecular weight and the amount of high molecular weight polyethylene that is used.
[0008] U.S. Pat. No. 3,541,011 to Davis et al., also discloses a solid lubricant whereby the characteristics of the lubricant such as hardness, deposition and rigidity are dependent on the molecular weight and on the amount used of high molecular weight polyethylene.
[0009] U.S. Pat. No. 3,729,415 to Davis et al., discloses a combination of polyethylene and hydrocarbon oil in a stick lubricant that does not contain extreme anti-wear materials to prevent excessive wear.
[0010] U.S. Pat. No. 4,915,856 to Jamison discloses an alternative solid polymeric stick formula, which includes lead and other metallic powder in either single or co-extruded compositions. While the metallic powder offers anti-wear properties, it also can pollute the environment, such as ground water, when it drops alongside and also can present hazardous conditions for rail workers. Inclusion of metallic powders which may be considered hazardous by the E.P.A. is undesirable to railroads and transits.
SUMMARY OF THE INVENTION
[0011] In order to overcome problems inherent in the prior art there has been devised by the present invention a solid lubricant and composition useful for lubricating the flanges of locomotive wheels, railcar wheels, rail track, and in applications where it is desirable to reduce friction when metal contacts metal. The solid lubricant of the present invention comprises from about twenty-five percent to about seventy percent by volume of a polymeric carrier, and in combination about five to seventy-five percent by volume of organic and inorganic extreme pressure additives, including an organic and inorganic powder lubricant and optionally a synthetic extreme pressure anti-wear liquid oil and/or an optical brightener so that the lubricant can be seen under black light conditions to allow verification that the lubricant is coating the surface to which it is applied.
[0012] In the preferred embodiment, the solid lubricant composition comprises two portions, namely a first portion and a second portion. The first portion of the lubricant stick is composed generally of the following formula one: from about twenty-five percent to about seventy percent by volume (preferably from about thirty-five percent to about thirty-nine percent) of a polymeric carrier with a relatively high melt index, such as a linear low density polyethylene, a low density polyethylene, a polyolefin or a synthetic wax; from about five percent to about seventy-five percent by volume (preferably about sixty percent) of organic and inorganic powder; from about zero percent to about twenty percent by volume (preferably about one percent to about four percent) of a synthetic extreme pressure anti-wear oil; and from about zero percent to about one percent by volume (preferably about one percent) of an optical brightener. The second portion of the lubricant stick is composed generally of the following formula two: from about twenty-five percent to about seventy percent by volume (preferably about twenty-nine percent) of linear high density polyethylene polymeric carrier with a relatively low melt index; from about five percent to about seventy-five percent by volume (preferably about sixty-five percent) of organic and inorganic powder; from about zero percent to about twenty percent by volume (preferably about five percent) of a synthetic extreme pressure anti-wear oil; and from about zero percent to about one percent by volume (preferably about one percent) of an optical brightener.
[0013] The solid lubricant of the present invention uses two distinct thermo-polymer resins with different melt flow temperatures and melt point indexes to form a two portion lubricant. The first portion of applied lubricant is rapidly penetrated into a metallic surface when lubricant is first applied to a metallic surface. The second portion of the lubricant is applied more slowly, when less is needed.
[0014] Still other objects and advantages of the present invention will become readily apparent to those skilled in this art from the following detailed description wherein I have shown and described only the preferred embodiment of the invention, simply by way of illustration of the best mode contemplated by carrying out my invention. As will be realized, the invention is capable of modification in various obvious respects all without departing from the invention. Accordingly, the drawings and description of the preferred embodiment are to be regarded as illustrative in nature, and not as restrictive.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 is a perspective view of the two portions of the solid lubricant stick of the present invention.
[0016] FIG. 2 is a perspective view of the two portions of the solid lubricant stick of the present invention showing how the two portions are welded together to form a one piece lubricant stick.
[0017] FIG. 3 is a graph showing the reduced mechanical energy needed for a locomotive to go through a single lap having its wheel flanges lubricated with the present solid lubricant stick versus having dry wheel flanges.
[0018] FIG. 4 is a graph showing the wear on a solid lubricant stick of the present invention first on dry wheel flanges and after the train has reached a steady state of lubrication.
[0019] FIG. 5 is a graph showing the effect on lateral forces for a dry inside rail versus a lubricated inside rail, lubricated by means of the present solid lubricant stick. No significant effect on lateral sources indicates that the lubricant was not migrating to the top of the rail.
[0020] FIG. 6 is a graph showing the effect on lateral forces for a dry outside rail versus a lubricated outside rail, lubricated by means of the present solid lubricant stick. Also, in FIG. 6 it can be seen that there is no significant effect on lateral sources indicating that the lubricant was not migrating to the top of the rail.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0021] While the invention is susceptible of various modifications and alternative constructions, certain illustrated embodiments thereof have been shown in the drawings and will be described below in detail. It should be understood, however, that there is no intention to limit the invention to the specific form disclosed, but, on the contrary, the invention is to cover all modifications, alternative constructions, alternative uses, and equivalents falling within the spirit and scope of the invention as defined in the claims.
[0022] Referring now to the drawings in general and to FIG. 1 of the drawings in particular, there is shown a perspective view of the two portions of the solid lubricant stick of the present invention. The lubricant stick of the present invention is shown generally by the number 10 . It can be seen in FIG. 1 that the lubricant stick 10 of the present invention starts out as two separate portions ( 12 , 14 ) having two distinct formulations.
[0023] The first portion 12 of the lubricant stick 10 is composed generally of the following formula one: from about twenty-five percent to about seventy percent by volume of a polymeric carrier with a relatively high melt index, such as a linear low density polyethylene, a low density polyethylene, a polyolefin or a synthetic wax; from about five percent to about seventy-five percent by volume of organic and inorganic powder; from about zero percent to about twenty percent by volume of a synthetic extreme pressure anti-wear oil; and from about zero percent to about one percent by volume of an optical brightener.
[0024] In the preferred embodiment, the polymeric carrier is either a linear low density or low polyethylene, however, synthetic waxes with a low melt flow temperature of less than two hundred fifty degrees Fahrenheit can also be used. If a synthetic wax polymeric carrier is used instead of a linear low or low density polyethylene polymeric carrier, the melt flow temperature for the synthetic wax polymeric carrier in formula one is from about fifteen to two hundred, with a melt flow temperature between about two hundred and three hundred degrees Fahrenheit. If the polymeric carrier is either a linear low density or low density polyethylene with a relatively high melt index, the melt index of the polymeric carrier is generally from about ten to sixty and the melt flow temperature is generally lower between about three hundred and three hundred and fifty degrees Fahrenheit.
[0025] This polymeric carrier which is mixed with organic and inorganic anti-wear powders is from the polyolefin family and can be used in either of two forms. The polymeric carrier can be either a powder or pellet form, wherein the pellets are usually between 0.1 and 0.15 inch and are irregularly shaped, or in a ball, cylinder or hexagon shapes.
[0026] In the preferred embodiment, the first portion 12 of the lubricant stick 10 uses about sixty-five percent organic and inorganic powder by volume, coming from a combination of about fifty percent molybdenum disulfide powder, about ten percent graphite powder, and one to four percent by volume of synthetic extreme pressure anti-wear liquid oil and about one percent optical brightener. Other combinations of these and other ingredients will be obvious to one skilled in the art and the above formulation is given by way of illustration only. For example, the percentage of polymeric carriers used can vary according to how quickly or slowly the desired deposition of the solid lubricant is against a steel surface. The percentage of inorganic powder can vary depending on how much organic powder is used and the percentage of organic powder used can vary depending on how much inorganic powder is used.
[0027] It is also not necessary to use any extreme pressure anti-wear liquid oil or the amount of liquid oil used could be increased to from about five percent by volume to about twenty percent by volume of the composition. More than one type of liquid oil can be used and the percentage used can be varied depending on the percentage of inorganic or organic powders used. The percentage of liquid oil can also be varied depending on the percentage of liquid oil or oils needed for blending of the dry powdered materials.
[0028] The addition of an optical brightener is also not required, but is used only so that by using a black light, the lubricant deposition on wheel flanges or rail track can be verified.
[0029] In general, the first portion 12 of the lubricant stick 10 , as seen in FIG. 1 , is made of a lower melt flow temperature and higher melt index polymeric carrier than the second portion 14 of the lubricant stick 10 . The first portion 12 of the lubricant stick 10 has these characteristics so that it is rapidly penetrated into a metallic surface. In the embodiment shown in FIG. 1 , the first portion 12 of the lubricant stick 10 generally comprises about one-third of the total length of the lubricant stick 10 , so that an appropriate amount of lubricant is absorbed into the metallic surface when the lubricant is first applied, however, this dimension is easily varied, and the present invention is not to be limited to this proportion.
[0030] In FIG. 1 , it can further be seen that the lubricant stick 10 of the present invention also has a second portion 14 . The second portion 14 of the lubricating stick 10 is composed of a different formula than the first portion 12 , with that formula, formula two, generally being the following: from about twenty-five percent to about seventy percent by volume of linear high density polyethylene polymeric carrier with a relatively low melt index; from about five percent to about seventy-five percent by volume of organic and inorganic powder; from about zero percent to about twenty percent by volume of a synthetic extreme pressure anti-wear oil; and from about zero percent to about one percent by volume of an optical brightener.
[0031] In the formulation of the second portion 14 of the lubricant stick 10 , the organic and inorganic powder is preferably the same as used in the first portion 12 of the lubricant stick 10 . The difference in the formulation of the second portion 14 of the lubricant stick 10 is that the second portion 14 has a higher melt flow temperature and a lower melt index of the polymeric carrier than does the first portion 12 . In formula two, the polymeric carrier can be a linear high-density polyethylene, a high-density polyethylene, a high-density polypropylene or a high-density methylpentene.
[0032] In the preferred embodiment, a high density polyethylene is used as the polymeric carrier in formula two with a generally low melt index of about five or less. More particularly, the melt index is usually between about 0.1 and 1.0. The melt flow temperature is generally higher, between about three hundred fifty and four hundred degrees Fahrenheit. If a polypropylene is used instead, the melt index range is between about thirty and fifty and the melt flow temperature is between about four hundred and four hundred eighty degrees Fahrenheit. If methylpentene is used as the polymeric carrier, the melt index is between twenty and one hundred eighty and the melt flow temperature is between about five hundred and five hundred fifty degrees Fahrenheit. As with the variations described with reference to formula one, it is also within the spirit and scope of the present invention to vary the percentages and ingredients used in formula two. The above formulation is given by way of illustration only.
[0033] The organic and inorganic powder used in the second formula formulations is used as an anti-wear additive. In its preferred embodiment, it contains a minimum of about sixty-five percent by volume of inorganic molybdenum disulfide powder, graphite powder, talc powder, mica powder or calcium carbonate powder. The significant percentage of these extreme pressure anti-wear powders provides the lubrication necessary to prevent excessive wear due to rolling and sliding contact between wheel flanges of a locomotive and rail track.
[0034] The synthetic liquid oil in the formulation of the present lubricant stick 10 also acts as an extreme pressure anti-wear additive. The synthetic liquid oil is biodegradable mineral-based oil that assists in the blending of the polymeric carrier and the extreme pressure anti-wear powders. A ratio of about four parts per hundred to about fifteen parts per hundred of the synthetic oil can be used. In the preferred embodiment, about five percent by volume of synthetic oil in the formulation is the most effective. Less than four percent of synthetic oil by volume in the formulation is not sufficient to contribute to the mixing of the anti-wear powders and the polymeric resin of the polymeric carrier.
[0035] In the preferred embodiment, optical brightener is added to both the formulations. As previously indicated, optical brightener allows the lubricant of the present invention to be seen under black light conditions. The optical brightener therefore verifies that the solid lubricant 10 is coating the surface to which it is being applied. About one percent by volume of optical brightener is preferred in the formulation to ensure visibility, however zero to about one percent by volume may be utilized.
[0036] The solid lubricant stick 10 of the present invention uses the two formulas combined in the single lubricant stick, one example of which can be seen in FIG. 2 . This single lubricant stick having two distinct thermo-polymeric resins with distinctly different melt flow temperatures and melt point indices, so that the rate at which the lubricant is applied and absorbed can be varied. When the thermo-polymeric lubricant is first applied to the metallic surface, more lubricant is needed because the metallic surface has no lubrication and is most vulnerable to excessive wear. The first applied lubricant from the first portion 12 of the lubricant stick 10 is made of the lower melt flow temperature and the higher melt index polymeric carrier and is rapidly penetrated into the metallic surface to which it is applied thereby substantially reducing the coefficient of friction between two metallic surfaces in contact.
[0037] The second applied lubricant that is in the second portion 14 of the same lubricant stick 10 has a higher melt flow temperature and a lower melt index. After a coating of lubrication has been established by the first portion 12 of the lubricant stick 10 , less of the lubricant is needed to maintain a low coefficient of friction. Thus, the lower melt flow and higher melt index polymer of the first portion 12 of the lubricant stick 10 is no longer needed, and would be wasted, if applied.
[0038] As the lower melt flow temperature and higher melt index polymer is needed and used at a slower rate, the second portion 14 of the lubricant stick 10 is used, with the higher melt flow temperature and lower melt index, the second portion 14 of the lubricant stick 10 , acts as a maintenance material to provide continuous lubrication. In the preferred embodiment, approximately the first third 16 of lubricant stick 10 is made up of the first formula with the higher melt flow temperature and lower melt index, with the other two-thirds comprising the second formula. After the first portion 12 of the lubricant stick 10 has been used to substantially lubricate a dry wheel flange and gauge side of a rail track, the first portion 12 is no longer on the lubricant stick 10 and the second portion 14 then is used to provide lubricating maintenance to the flanges of the wheel of the locomotive and gauge side of the rail track.
[0039] Referring now to FIG. 2 of the drawings, shown is a perspective view of one embodiment of the solid lubricant stick 10 showing how the two portions 12 and 14 are welded together to form a one piece lubricant stick 10 . It can be seen in FIG. 2 that the first portion 12 of the lubricant stick 10 is welded to the second portion 14 of the lubricant stick 10 with a double “v” butt weld 18 . It is within the spirit and scope of the invention to use other weld formations, and the “v” butt weld 18 of FIG. 2 is used only as an example of a way to weld the two portions 12 and 14 together. It can be seen in FIGS. 1 and 2 that the first portion 12 of the lubricant stick 10 has a first end 20 and a second end 22 . Similarly, the second portion 14 of the lubricant stick 10 has a first end 24 and a second end 26 . The second end 22 of the first portion 12 of the lubricant stick 10 is welded to the first end 24 of the second portion 14 of the lubricant stick 10 so that a single width lubricant stick 10 is formed.
[0040] There is a four-step process of producing the lubricating stick 10 having two portions 12 and 14 . First, all materials for the first formula in the first portion 12 are blended and extruded into pellet size shapes. It is however, not necessary to pelletize the ingredients first, for instance, they can be mixed together very well with a heavy duty mixer that confines dust, or any other manner of pelletizing the ingredients that keeps dust from flying freely. Second, all materials for the second formula in the second portion 14 are blended and extruded into pellet size shapes or mixed in a heavy-duty mixer like the first formula. Third, a desired shape of each of the portions 12 and 14 of the solid lubricant stick 10 are made using extrusion, transfer molding or injection molding. Fourth, the two shapes from step three are welded together to form a single lubricant stick 10 . The two portions 12 and 14 can be joined together in any common means, including through use of extrusion welding, hot air welding or inject welding. Additionally, the two portions could be co-extruded together.
[0041] There are several methods that can be used to join the two portions 12 and 14 of the lubricating stick 10 of the present invention together. One such method is hot air welding, which utilizes hot air to heat the thermoplastic polymeric material. In this method, a hot air welder is held in one hand and a welding rod is held in the other hand. Welding material is applied between the two portions 12 and 14 and when the thermoplastic polymeric material cools, the two portions 12 and 14 are joined together as one piece. Another form of hot air welding uses steel paddles coated with Teflon®. The paddles are heated on both sides and the second end 22 of the first portion 12 and the first end 24 of the second portion 14 of the lubricant stick 10 are pressed against the paddles. When the thermoplastic polymeric material begins to soften, the heated end 22 of the first portion 12 is butted against the heated end 24 of the second portion 14 .
[0042] Another method of joining two portions 12 and 14 of the lubricating stick 10 together is by high speed welding. In high speed welding, a first tacking tip is used to clean and prepare the ends 22 and 24 of the portions 12 and 14 to be attached to each other. Then, a high speed welding tip having a feeding channel is used to join the two portion ends 22 and 24 , such that a welder does not need to hold a welding rod in his hand.
[0043] Another method joining two portions 12 and 14 together called injectiwelding uses heat from the welding tip to preplasticize the welding surface of the thermoplastic polymeric material. Molten plastic is injected under pressure below the surface of the thermoplastic polymeric material and into the weld areas thereby fusing the plastic together to form a solid weld. With injectiweld, because the orifice in the weld tip is submerged, surface preparation is not necessary.
[0044] Another method of joining two portions 12 and 14 of a solid lubricant stick 10 together is the extruded welding process. In this process, a continuous flow of extruded material that is used to join the two ends 22 and 24 of the two portions 12 and 14 of the solid lubricant stick 10 is pressed onto the welding surface. The extruder forces the joining material onto the ends 22 and 24 of the two portions 12 and 14 .
[0045] Another method of joining two portions 12 and 14 of a solid lubricant stick 10 together is through co-extrusion. Co-extrusion is the simultaneous extrusion of the first portion and the second portion through a single die.
[0046] Referring now to FIG. 3 of the drawings, a graph shows the reduced mechanical energy needed for a locomotive to go through a single lap having its wheel flanges lubricated with the present solid lubricant stick versus having dry wheel flanges. In FIG. 3 , it can be seen that there is about a forty percent average reduction in the mechanical energy needed for a train to travel around a test loop after the solid lubricant stick 10 of the present invention has been applied to locomotive wheel flanges.
[0047] There are three sections in FIG. 3 . The first section 28 of FIG. 3 shows a lap number 30 along an x-axis 32 and the mechanical energy in kWh 34 along the y-axis 36 . In the first section 28 of FIG. 3 , the dry baseline 38 is shown for laps 34 - 42 . During these laps, the average mechanical energy expended by a locomotive was 241.74 kWh. After the solid lubricant sticks 10 of the present invention were applied to the wheel flanges of a locomotive, starting at lap 43 , the mechanical energy expended showed an immediate drop once the train was at test speed, as seen in the second section 40 of FIG. 3 . By the fourth lap after lubrication 44 , the energy readings had dropped to what was established as the approximate steady state condition, 144.3 kWh. The third section 46 of FIG. 3 shows that for laps 60 - 66 , the average steady state lubrication was maintained for an average steady state lubrication was maintained for an average mechanical energy saving of thirty-nine and nine tenths percent.
[0048] Referring now to FIG. 4 of the drawings, a graph shows the wear on a solid lubricant stick 10 of the present invention, as seen in FIG. 2 , first on dry wheel flanges and then after the train has reached a steady state of lubrication. In FIG. 4 , the consumption rate 48 (wear) in inches of the lubricant stick 10 , in FIG. 2 , is shown along the y-axis 50 , and the number of laps 52 is shown along the x-axis 54 . Thus, FIG. 4 shows how much of the solid lubricant stick 10 has been consumed after thirty-four laps around a track. FIG. 4 shows that as the train becomes lubricated with the solid lubricant stick 10 , less of the lubricant is needed to maintain the reduction in energy necessary to operate the train.
[0049] Referring now to FIG. 5 of the drawings, a graph shows the effect on lateral forces for a dry inside rail versus an inside rail lubricated by means of the present solid lubricant stick. The inside and outside rail referred to in the discussion of FIGS. 5 and 6 refer to the position of the rail in a curve. When there is no migration of the lubricant to the tread of the wheel of a service truck or to the top of rail (either on the inside or outside), the lubricant does not effect how the truck or wheels adhere to the rail throughout a curve.
[0050] In FIG. 5 , lateral load force units called kips are measured along the y-axis 56 . The x-axis 58 represents the first pair of columns 60 , the maximum lateral load force 62 , and in the third pair of columns 68 , the average lateral load force 70 . Each pair of columns 60 , 64 and 68 is divided into two sections. The first pair of columns 60 has a first section 72 and a second section 74 . So, the first section 72 of the first pair of columns 60 shows the maximum lateral load force 62 under dry conditions and the second section 74 of the first pair of columns 60 shows the maximum lateral load force 62 after lubrication with the present lubricant stick 10 .
[0051] In a similar manner, the second pair of columns 64 in FIG. 5 have a first section 76 and a second section 78 . The first section 76 represents the minimum lateral load force 66 under dry conditions and the second section 78 of the second pair of columns 64 represents the minimum lateral load force 66 after lubrication with the present lubricant stick 10 . The third pair of columns 68 has a first section 80 and a second section 82 . The first section 80 of the third pair of columns 68 represents the average lateral load force 70 under dry conditions and the second section 82 of the third pair of columns 68 represents the average lateral load force 70 after lubrication with the present lubricant stick 10 . It can be seen, therefore, in FIG. 5 , that there is very little change between lateral load forces under dry conditions on an inside rail versus after lubrication on an inside rail with the present lubricant stick 10 . No significant effect on the lateral load forces indicate that the lubricant of the lubricant stick 10 was not migrating to the top of the inside rail.
[0052] Referring now to FIG. 6 , there is a graph showing the effect on lateral forces for a dry outside rail versus an outside rail lubricated by means of the present solid lubricant stick 10 . In FIG. 6 , it also can be seen that there is no significant effect on lateral load forces indicating that the lubricant was not migrating to the top of the outside rail. FIG. 6 is similar to FIG. 5 , except instead of showing the effect on lateral forces on an inside rail, FIG. 6 shows the same data for an outside rail.
[0053] In FIG. 6 , lateral load force units (kips) are measured along the y-axis 56 and the x-axis 58 represents lateral load force. The figure shows, in the first pair of columns 84 the maximum lateral force 86 , in the second pair of columns 88 the minimum lateral load force 90 , and in the third pair of columns 92 the average lateral load force 94 . Like FIG. 5 , in FIG. 6 , each pair of columns 84 , 88 and 92 are divided into two sections. The first pair of columns 84 has a first section 96 representing the dry conditions and a second section 98 representing the lubricated conditions. The second pair of columns 88 has a first section 100 representing dry conditions and a second section 102 representing lubricated conditions. The third pair of columns 92 has a first section 104 representing dry conditions and a second section 106 representing lubricated conditions.
[0054] It can be seen, therefore, in FIG. 6 , that with maximum lateral load force 86 , minimum lateral load force 90 , and average lateral load force 94 , there is no significant change in lateral load forces under dry conditions on an outside rail versus after lubrication on an outside rail with the present lubricant stick 10 . So, in FIG. 6 , no significant effect on the lateral load forces indicates also that the lubricant of the lubricant stick 10 of the present invention was not migrating to the top of the outside rail.
[0055] While there is shown and described the present preferred embodiment of the invention, it is to be distinctly understood that this invention is not limited thereto but may be variously embodied to practice within the scope of the following claims. From the foregoing description, it will be apparent that various changes may be made without departing from the spirit and scope of the invention as defined by the following claims. | A solid lubricant and composition useful for lubricating the flanges of locomotive wheels, railcar wheels, rail track and in applications where it is desirable to reduce friction when metal contacts metal. The solid lubricant having from about twenty-five percent to about seventy percent by volume of a polymeric carrier, about five to seventy-five percent by volume of organic and inorganic extreme pressure additives, about zero to twenty percent by volume synthetic extreme pressure anti-wear liquid oil, and about zero to one percent by volume optical brightener. | 2 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a semiconductor device and a manufacturing method therefor, and more particularly, to a bump structure of a semiconductor device.
[0003] 2. Description of the Related Art
[0004] FIG. 10 illustrates a conventional solder bump structure. As illustrated in FIG. 10 , a polyimide 2 is formed on an uppermost layer metal 1 . An opening is formed so that the uppermost layer metal 1 is exposed. A sputtered film 3 and an under bump metal (UBM) 4 are laminated in the opening, and a solder 5 is provided thereon.
[0005] As the process goes through generations, a bump diameter and a bump pitch (distance between bumps) have become smaller. When a solder bump is reflowed, the solder bump is melted and a width of the solder bump becomes larger. Hence, it is necessary to reduce an amount of solder as the bump pitch decreases for the purpose of preventing a short circuit between bumps.
[0006] However, reducing the amount of the solder results in a decreased standoff (distance between a chip and amounting board in flip-chip mounting), which increases a risk of generation of voids (air bubbles) when an underfill resin is injected between the chip and the mounting board.
[0007] Instead of the solder bump structure, a columnar bump structure is capable of decreasing the bump pitch while maintaining the standoff. The columnar bump structure is a structure in which a solder layer is formed on a column made of a high melting point metal such as Cu.
[0008] However, even the columnar bump structure has a weak point. Most of the columnar bump structure is made up of a high melting point metal such as Cu. Therefore, due to stresses produced in flip-chip mounting (reflow), breakage of the bump may occur. Therefore, when the columnar bump structure is applied to a product, from the viewpoint of improving yield and reliability, some measures to improve stress tolerance are necessary.
[0009] As illustrated in Japanese Patent Application Laid-open No. Hei 6-333931, a columnar bump has a structure in which a solder layer is formed on a high melting point metal which has excellent conductivity such as Cu. A thickness of the solder layer is determined by design. When an amount of the solder is large, as illustrated in Japanese Patent Application Laid-open No. Hei 6-333931, the solder goes around a periphery of the top to the side of columnar Cu to cover the columnar Cu. On the other hand, as illustrated in FIG. 11 , when the amount of the solder is set to be small, a surface tension of the solder 5 makes the solder 5 formed only on the top of a columnar Cu 6 .
[0010] FIG. 12 is a cross-sectional view of the columnar bump structure after mounting. As illustrated in FIG. 12 , an auxiliary solder 8 which is a low melting point solder is provided on a substrate pad 7 on the side of the mounting board. The auxiliary solder 8 and the solder 5 are disposed so as to be opposed to each other. By heating them, soldering is carried out.
[0011] In particular, in a product with a large chip size (for example, 15 mm×15 mm or larger), in flip-chip mounting, due to a difference in thermal expansion coefficient between the chip and the mounting board and due to a warp in the mounting board because of heat, vertical and horizontal stresses are applied to a bump positioned on an outer side of the chip.
[0012] The solder acts as an alleviator of the stresses in mounting. However, in Japanese Patent Application Laid-open No. Hei 6-333931, in the columnar bump structure, a ratio of the solder, which acts as an alleviator of the stresses in mounting, in the bump is small compared with the case of the solder bump structure. When the ratio of the solder in the bump structure is small, the stresses in mounting cannot be completely alleviated, and breakage (cracks) occurs in regions surrounded by broken lines of FIG. 12 (interface between the bump and the chip) and in a solder portion.
[0013] On the other hand, when the amount of the solder is large, the solder is melted so as to cover the columnar Cu, and hence the width of the bump becomes larger. When the bump pitch is small, there is a high risk that a short circuit between bumps occurs, which means application of the structure is difficult. Further, an area occupied by the bump in design becomes larger, and accordingly the structure is not appropriate for a decreased chip size.
[0014] Japanese Patent Application Laid-open No. Sho 62-234352 describes a two-layer bump having a high melting point solder as its lower layer and a low melting point solder as its upper layer. The bump described in Japanese Patent Application Laid-open No. Sho 62-234352 is formed only of a solder, and hence resistance of the bump is higher. The resistance of the bump becomes higher as the bump diameter becomes smaller, and hence high resistance due to a material of the bump is not preferable. Further, in reflow, even at a temperature which is lower than a melting point of the high melting point solder, the low melting point solder and the high melting point solder are gradually mixed with each other, and thus, it is difficult to maintain the columnar shape.
[0015] As described in the above, the conventional bump structures have a problem that inconvenience is caused in mounting which makes difficult the application thereof.
SUMMARY OF THE INVENTION
[0016] A semiconductor device according to one aspect of the present invention comprises: an electrode pad; and a columnar bump formed on the electrode pad, the columnar bump comprising: a first high melting point metal layer formed on the electrode pad; a first solder formed on the first high melting point metal layer; a second high melting point metal layer formed on the first solder; and a second solder which is formed on the second high melting point metal layer and is connected to an external. This makes it possible to increase a ratio of the solder in the columnar bump, to alleviate stresses in mounting, and to suppress breakage of the bump.
[0017] A semiconductor device according to another aspect of the present invention comprises: an electrode pad; and a columnar bump formed on the electrode pad, the columnar bump comprising: a first high melting point metal layer which is formed on the electrode pad, and occupies a half or more of a volume of the columnar bump; a first solder formed on the first high melting point metal layer; and a second solder which is formed on the first solder and is connected to an external. This makes it possible to increase the ratio of the solder in the columnar bump, to alleviate stresses in mounting, and to suppress breakage of the bump.
[0018] A semiconductor device according to another aspect of the present invention comprises: an electrode pad; a high melting point metal layer formed on the electrode pad; a first metal layer formed on the high melting point metal layer; and a second metal layer which is formed on the first metal layer, and has a hardness different from a hardness of the first metal layer, the high melting point metal layer, the first metal layer, and the second metal layer forming a columnar bump. This makes it possible to suppress breakage of the bump.
[0019] A method of manufacturing a semiconductor device according to another aspect of the present invention comprises forming a columnar bump on an electrode pad, the forming the columnar bump comprising: forming a first high melting point metal layer on the electrode pad; forming a first solder on the first high melting point metal layer; forming a second high melting point metal layer on the first solder; and forming a second solder on the second high melting point metal layer, the second solder being connected to an external. This makes it possible to increase the ratio of the solder in the columnar bump, to alleviate stresses in mounting, and to suppress breakage of the bump.
[0020] A method of manufacturing a semiconductor device according to another aspect of the present invention comprises forming a columnar bump on an electrode pad, the forming the columnar bump comprising: forming a first high melting point metal layer on the electrode pad, the first high melting point metal layer occupying a half or more of a volume of the columnar bump; forming a first solder on the first high melting point metal layer; and forming a second solder on the first solder, the second solder being connected to an external. This makes it possible to increase the ratio of the solder in the columnar bump, to alleviate stresses in mounting, and to suppress breakage of the bump.
[0021] The present invention can provide the semiconductor device having the bump structure which is capable of resolving inconvenience in mounting, and the manufacturing method therefor.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] In the accompanying drawings:
[0023] FIG. 1 is a cross-sectional view illustrating a structure of a columnar bump before reflow of a semiconductor device according to a first embodiment;
[0024] FIG. 2 is a cross-sectional view illustrating the structure of the columnar bump after the reflow of the semiconductor device according to the first embodiment;
[0025] FIGS. 3A and 3B are plan views illustrating the structure of the columnar bump of the semiconductor device according to the first embodiment;
[0026] FIG. 4 is a cross-sectional view illustrating a state of the semiconductor device according to the first embodiment after mounting;
[0027] FIGS. 5A and 5B are cross-sectional views illustrating manufacturing steps of a method of manufacturing the semiconductor device according to the first embodiment;
[0028] FIGS. 6C and 6D are cross-sectional views illustrating manufacturing steps of the method of manufacturing the semiconductor device according to the first embodiment;
[0029] FIG. 7E is a cross-sectional view illustrating a manufacturing step of the method of manufacturing the semiconductor device according to the first embodiment;
[0030] FIG. 8 is a cross-sectional view illustrating a structure of a columnar bump before reflow of a semiconductor device according to a second embodiment;
[0031] FIG. 9 is a cross-sectional view illustrating a structure of a columnar bump before reflow of a semiconductor device according to a third embodiment;
[0032] FIG. 10 is a cross-sectional view illustrating a structure of a solder bump of a conventional semiconductor device;
[0033] FIG. 11 is a cross-sectional view illustrating a structure of a columnar bump of a conventional semiconductor device; and
[0034] FIG. 12 is a cross-sectional view illustrating a state of the conventional semiconductor device after mounting.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
First Embodiment
[0035] A semiconductor device according to a first embodiment of the present invention is now described with reference to the drawings. FIG. 1 is a cross-sectional view illustrating a structure of a columnar bump before reflow of the semiconductor device according to this embodiment. As illustrated in FIG. 1 , a semiconductor device 10 according to this embodiment includes an uppermost layer metal 11 , a polyimide 12 , a sputtered film 13 , a first high melting point metal layer 14 , a first solder 15 , a second high melting point metal layer 16 , and a second solder 17 .
[0036] The polyimide 12 is formed on the uppermost layer metal 11 . An opening for exposing the uppermost layer metal 11 is formed in the polyimide 12 . A region in which the opening is formed is to be an electrode pad. The sputtered film 13 is provided on the uppermost layer metal 11 and the polyimide 12 in the opening.
[0037] The columnar bump is formed on the electrode pad. The columnar bump has a lamination structure in which the first high melting point metal layer 14 , the first solder 15 , the second high melting point metal layer 16 , and the second solder 17 are laminated in the stated order from the bottom. More specifically, in this embodiment, the columnar bump has a structure in which two two-layer structures each having a high melting point metal layer and a solder laminated therein are stacked. In other words, two high melting point metal layers and two solder layers are alternately laminated.
[0038] As the first high melting point metal layer 14 and the second high melting point metal layer 16 , a high melting point metal whose resistance is lower than (whose conductivity is higher than) those of the solders may be used. Exemplary high melting point metals which can be used as the first high melting point metal layer 14 and the second high melting point metal layer 16 include Cu and Au. The conductivities of Cu and Au are as follows.
[0039] Cu: 59.0E6 (S/m)
[0040] Au: 45.5E6 (S/m)
[0041] As the first solder 15 , a solder having a melting point which is higher than that of the second solder 17 as an uppermost layer is used so as not to be melted in a reflow process at the end of a bump forming process. More specifically, the first solder 15 and the second solder 17 are metal layers having different hardnesses. In particular, it is preferable that the first solder 15 be a metal layer which is softer than the first high melting point metal layer 14 . For example, it is preferable that a high melting point solder containing a soft metal such as lead (Pb) be used as the first solder 15 .
[0042] Exemplary kinds of solder include the following.
SnAgCu Solder
[0043] SnAgCu solders are almost made of Sn and contain about 0.3% of Ag and about 0.5% of Cu. The conductivities of the solders are dominated by the conductivity of Sn, 7.9E6 (S/m). The melting points of the SnAgCu solders are about 230° C.
SnZnBi Solder
[0044] The melting points of SnZnBi solders are lowered by adding Zn and Bi thereto, and are about 180° C. The conductivities of the solders are dominated by the conductivity of Sn, 7.9E6 (S/m)
Pb Solder
[0045] Pb solders contain about 95% of Pb. The melting points of the solders are about 330° C. The conductivity of Pb is 4.8E6 (S/m).
[0046] As illustrated in FIG. 1 , it is assumed that a thickness of the first high melting point metal layer 14 , a thickness of the second high melting point metal layer 16 , a thickness of the first solder 15 , and a thickness of the second solder 17 are M 1 , M 2 , h 1 , and L 1 , respectively. The thickness M 1 of the first high melting point metal layer 14 and the thickness M 2 of the second high melting point metal layer 16 satisfy Equation (1).
[0000] M1≧M2 (1)
[0047] More specifically, for the purpose of supporting the second high melting point metal layer 16 which is an upper layer by the first high melting point metal layer 14 which is a lower layer, the thickness M 1 of the first high melting point metal layer 14 which is the lower layer is set to be substantially equal to or larger than the thickness M 2 of the second high melting point metal layer 16 which is the upper layer. This makes it possible to maintain a columnar shape of the columnar bump even after a mounting process, and it is possible to suppress shortening of a distance between a chip and a mounting board in flip-chip mounting (standoff).
[0048] Further, for the purpose of suppressing an increase in resistance, the thickness (volume) of the high melting point metal layers is made to be equal to or larger than the thickness (volume) of the solders. More specifically, a sum of the thicknesses of the first high melting point metal layer 14 and the second high melting point metal layer 16 is made to be equal to or larger than a sum of the thicknesses of the first solder 15 and the second solder 17 to satisfy Equation (2).
[0000] M 1 +M 2 ≧h 1 +L 1 (2)
[0049] This makes it possible to suppress the increase in resistance due to the columnar bump.
[0050] Further, the thickness L 1 of the second solder 17 is equal to or smaller than a half of a width (diameter) W of the columnar bump as expressed by Equation (3).
[0000] L 1≦0.5× W (3)
[0051] It is to be noted that, here, a shape of the columnar bump seen from above is substantially a circle and the columnar bump is substantially a circular cylinder.
[0052] FIG. 2 illustrates the structure of the columnar bump after the reflow at a bump formation finishing stage. As illustrated in FIG. 2 , the second solder 17 as the uppermost layer is once melted in the reflow process to complete the formation of the columnar bump. If the thickness L 1 of the second solder 17 is equal to or smaller than a half of the width W of the columnar bump so as to satisfy Equation (3), when the second solder 17 is melted, the melted solder does not go around a periphery of the top to the side of the columnar bump. This can suppress horizontal spread of the solder, and thus, even when a chip size is decreased, a short circuit between bumps can be prevented.
[0053] FIGS. 3A and 3B are plan views of the columnar bump seen from above. The shape of the columnar bump seen from above may be substantially circular as illustrated in FIG. 3A , and may be a polygon as illustrated in FIG. 3B . FIG. 3B illustrates a case in which the shape of the columnar bump seen from above is an octagon. When the high melting point metal layers formed of Cu or the like are formed in the shape of a polygon as illustrated in FIG. 3B , instead of Equation (3), Equation (4) is satisfied.
[0000] L1≦A (4)
[0000] where A is a distance from a center of the polygon to a vertex which is the farthest from the center.
[0054] As described in the above, this can prevent, when the second solder 17 is melted, the melted solder from going around the periphery of the top to the side of the columnar bump, and thus, the horizontal spread of the solder can be suppressed.
[0055] FIG. 4 illustrates a state of the semiconductor device after the mounting. As illustrated in FIG. 4 , the second solder 17 as the uppermost layer of the columnar bump formed as illustrated in FIG. 2 and an auxiliary solder 22 formed on a substrate pad 21 of the mounting board are disposed so as to be opposed to each other, and reflow is carried out under temperature conditions in which only the second solder 17 is melted. It is to be noted that a low melting point solder which is melted at a temperature that is substantially similar to the melting point of the second solder 17 is used as the auxiliary solder 22 on the side of the mounting board. In this way, the semiconductor device is flip-chip mounted on the mounting board.
[0056] Conventionally, in flip-chip mounting, stresses due to a difference in thermal expansion coefficient between the chip and the mounting board and due to a warp in the mounting board because of heat cause breakage of the bump. However, according to the present invention, the ratio of the solder in the bump structure is made larger, and hence, when stresses are produced in flip-chip mounting, the stresses can be alleviated by ductility of the solder layers. More specifically, displacement due to the difference in thermal expansion coefficient between the chip and the mounting board and due to the warp in the mounting board because of heat can be made smaller. This makes it possible to prevent the breakage of the bump.
[0057] Further, the structure is a lamination structure in which the high melting point metal layers and the solders are alternately laminated, and the solder layer which is the lower layer also acts as an alleviator of the stresses. In this way, the stresses can be alleviated by the whole bump, and the breakage of the bump can be prevented more effectively than in a case in which only an upper portion of the bump alleviates the stresses.
[0058] The second high melting point metal layer 16 is formed under the second solder 17 as the uppermost layer which is melted in the reflow. The second high melting point metal layer 16 is not completely alloyed with the second solder 17 , which effectively maintains the shape of the columnar bump. Further, by restricting the ratio of the solder in the columnar bump and maintaining a certain ratio of the high melting point metal whose resistance is low such as Cu, the increase in resistance of the bump portion can be suppressed to a minimum.
[0059] Here, a method of manufacturing the semiconductor device 10 according to this embodiment is now described with reference to FIGS. 5A to 7A . FIGS. 5A to 7A are cross-sectional views for describing the method of manufacturing the semiconductor device 10 according to this embodiment.
[0060] First, similarly to a conventional process, the polyimide 12 is formed on the uppermost layer metal 11 , and patterning is carried out so as to expose a part of the uppermost layer metal 11 . Then, the sputtered film 13 to be a conductive path in plating is formed on the uppermost layer metal 11 and the polyimide 12 . In this way, a structure illustrated in FIG. 5A is obtained.
[0061] After that, a thick photoresist (PR) 20 is formed, patterning is carried out, and an opening is formed in a region in which the columnar bump is to be formed. The photoresist 20 is formed so that its thickness is larger than a height H of the columnar bump to be formed in a later process (the sum of the heights of the first high melting point metal layer 14 , the first solder 15 , the second high melting point metal layer 16 , and the second solder 17 , i.e., H=M 1 +h 1 +M 2 +L 1 ). The sputtered film 13 is exposed in the opening in the photoresist 20 . In this way, a structure illustrated in FIG. 5B is obtained.
[0062] Then, with the photoresist 20 being formed on the sputtered film 13 , high melting point metal layers and solders are alternately laminated to form the columnar bump. In this embodiment, four layers of the first high melting point metal layer 14 , the first solder 15 , the second high melting point metal layer 16 , and the second solder 17 are grown by plating in succession without removing the photoresist 20 . In this way, a structure illustrated in FIG. 6C is obtained.
[0063] Here, as the first high melting point metal layer 14 and the second high melting point metal layer 16 , a high melting point metal whose resistance is lower than (whose conductivity is higher than) those of the solders and which is not melted at the temperature of the reflow (400° C. or lower) may be used. Further, as the first solder 15 , a solder whose melting point is higher than that of the second solder 17 as the uppermost layer is used so that the first solder 15 is not melted in the reflow process at the end of the bump forming process.
[0064] For example, when a solder whose melting point is about 230° C. is used as the second solder 17 , a solder whose melting point is 280° C. or higher is used as the first solder 15 . When a solder whose melting point is about 180° C. is used as the second solder 17 , a solder whose melting point is 230° C. or higher is used as the first solder 15 . In particular, it is preferable that a high melting point solder containing a soft metal such as lead (Pb) be used as the first solder 15 .
[0065] It is to be noted that the growth thicknesses of the respective layers satisfy, as described in the above, Equations (1) and (2), and, depending on the shape of the columnar bump seen from above, Equation (3) or (4). This makes it possible to suppress the increase in resistance due to the columnar bump, and to, while maintaining the shape of the columnar bump, prevent a short circuit between bumps.
[0066] After the plating process is completed, the photoresist 20 is removed to obtain a structure illustrated in FIG. 6D . After that, the unnecessary sputtered film 13 outside the columnar bump is removed by wet etching. Then, reflow is carried out at a temperature at which only the second solder 17 is melted. This makes only the second solder 17 melted once, and, as illustrated in FIG. 7E , the formation of the bump is completed. In mounting, reflow is carried out under temperature conditions in which only the second solder 17 is melted. This enables flip-chip mounting while maintaining the shape of the columnar bump.
[0067] As described in the above, according to the present invention, when stresses are produced in flip-chip mounting, the stresses can be alleviated by the ductility of the solders, and the breakage of the bump can be prevented. Further, the shape of the columnar bump can be maintained even after the mounting process, and it is possible to suppress shortening of the distance between the chip and the mounting board in flip-chip mounting. Still further, the increase in resistance of the columnar bump can be suppressed to a minimum.
Second Embodiment
[0068] A semiconductor device according to a second embodiment of the present invention is now described with reference to FIG. 8 . FIG. 8 is a cross-sectional view illustrating a structure of a columnar bump before reflow of the semiconductor device according to this embodiment. As illustrated in FIG. 8 , a semiconductor device 10 according to this embodiment includes an uppermost layer metal 11 , a polyimide 12 , a sputtered film 13 , a first high melting point metal layer 14 , a first solder 15 , a second high melting point metal layer 16 , a second solder 17 , a third solder 18 , and a third high melting point metal layer 19 .
[0069] In this embodiment, the columnar bump has a lamination structure in which the first high melting point metal layer 14 , the first solder 15 , the second high melting point metal layer 16 , the third solder 18 , the third high melting point metal layer 19 , and the second solder 17 are laminated in the stated order from the bottom. More specifically, in this embodiment, the columnar bump has a structure in which three two-layer structures each having a high melting point metal layer and a solder laminated therein are stacked. In other words, three high melting point metal layers and three solder layers are alternately laminated.
[0070] As the third high melting point metal layer 19 , similarly to the case of the first high melting point metal layer 14 and the second high melting point metal layer 16 , a high melting point metal whose resistance is lower than (whose conductivity is higher than) those of the solders may be used. As the first solder 15 and the third solder 18 , a solder having a melting point which is higher than that of the second solder 17 as an uppermost layer is used so as not to be melted in a reflow process at the end of a bump forming process. This makes it possible to maintain a shape of the columnar bump.
[0071] As illustrated in FIG. 8 , it is assumed that a thickness of the first high melting point metal layer 14 , a thickness of the second high melting point metal layer 16 , and a thickness of the third high melting point metal layer 19 are M 1 , M 2 , and M 3 , respectively. Further, it is assumed that a thickness of the first solder 15 , a thickness of the third solder 18 , and a thickness of the second solder 17 are h 1 , h 2 , and L 1 , respectively. It is to be noted that a height H of the whole columnar bump is substantially the same as that of the first embodiment.
[0072] For the purpose of suppressing an increase in resistance, the thickness (volume) of the high melting point metal layers is made to be equal to or larger than the thickness (volume) of the solders. More specifically, a sum of the thicknesses of the first high melting point metal layer 14 , the second high melting point metal layer 16 , and the third high melting point metal layer 19 is made to be equal to or larger than a sum of the thicknesses of the first solder 15 , the third solder 18 , and the second solder 17 to satisfy Equation (5).
[0000] M 1 +M 2 +M 3 ≧h 1 +h 2 +L 1 (5)
[0073] This makes it possible to suppress the increase in resistance due to the columnar bump.
[0074] The thickness L 1 of the second solder 17 satisfies Equation (3) or (4) described in the above depending on the shape of the columnar bump seen from above. This makes it possible to suppress horizontal spread of the solder and to prevent a short circuit between bumps.
[0075] The semiconductor device having the columnar bump of the lamination structure can be formed by a process similar to that described in the above. More specifically, a photoresist 20 is formed so as to be higher than the height H of the columnar bump (the sum of the heights of the first high melting point metal layer 14 , the first solder 15 , the second high melting point metal layer 16 , the second solder 17 , the third solder 18 , and the third high melting point metal layer 19 , i.e., H=M 1 +h 1 +M 2 +h 2 +M 3 +L 1 ), patterning is carried out, and an opening is formed in a region in which the columnar bump is to be formed.
[0076] Then, with the photoresist 20 being formed on the sputtered film 13 , high melting point metal layers and solders are alternately laminated to form the columnar bump. In this embodiment, six layers of the first high melting point metal layer 14 , the first solder 15 , the second high melting point metal layer 16 , the third solder 18 , the third high melting point metal layer 19 , and the second solder 17 are grown by plating in succession without removing the photoresist 20 .
[0077] It is to be noted that the number of the laminated high melting point metal layers and solders is not limited thereto. More than three high melting point metal layers and more than three solders may be formed. In that case, as solder layers other than the uppermost layer, a solder having a melting point which is higher than that of the solder layer as the uppermost layer is used. Then, the thicknesses of the respective layers are made to satisfy Equation (6).
[0000] M 1 +M 2 +M 3 + . . . +MX≧h 1 +h 2 + . . . +L 1 (6)
[0000] where the number of the laminated high melting point metal layers or solders is X.
[0078] The thickness L 1 of the second solder 17 satisfies Equation (3) or (4) described in the above depending on the shape of the columnar bump seen from above.
Third Embodiment
[0079] A semiconductor device according to a third embodiment of the present invention is now described with reference to FIG. 9 . FIG. 9 is a cross-sectional view illustrating a structure of a columnar bump before reflow of the semiconductor device according to this embodiment. As illustrated in FIG. 9 , a semiconductor device 10 according to this embodiment includes an uppermost layer metal 11 , a polyimide 12 , a sputtered film 13 , a first high melting point metal layer 14 , a first solder 15 , and a second solder 17 .
[0080] While, in the first and second embodiments, the high melting point metal layers and the solders are alternately laminated, in the third embodiment, such a structure is employed in which the high melting point metal layer formed of Cu or the like whose thickness is equal to or larger than a half of a height (H) of the bump is formed as a lower layer, and the first solder 15 and the second solder 17 are formed in succession as an upper layer.
[0081] In this embodiment, also, as the first solder 15 , a solder whose hardness is different from that of the second solder 17 as an uppermost layer and which has a melting point that is higher than that of the second solder 17 is used. In particular, it is preferable that the first solder 15 be a metal layer which is softer than the first high melting point metal layer 14 .
[0082] As illustrated in FIG. 9 , it is assumed that a thickness of the first high melting point metal layer 14 , a thickness of the first solder 15 , and a thickness of the second solder 17 are M 1 , h 1 , and L 1 , respectively. It is to be noted that the height H of the whole columnar bump is substantially the same as that of the first embodiment. In this embodiment, the thicknesses of the respective layers satisfy Equation (7).
[0000] M 1 >h 1 +L 1 (7)
[0083] This makes it possible to suppress an increase in resistance due to the columnar bump.
[0084] The thickness L 1 of the second solder 17 satisfies Equation (3) or (4) described in the above depending on the shape of the columnar bump seen from above.
[0085] As described in the above, in the third embodiment, by adding the first solder 15 whose melting point is higher than that of the second solder 17 between the first high melting point metal layer 14 and the second solder 17 , the height of the bump can be maintained. Further, an amount of the solders which are mixed with each other in reflow can be suppressed to a minimum, whereby horizontal spread of the bump beyond its original shape caused by being melted can be suppressed.
[0086] As described in the above, according to the present invention, by providing a solder between high melting point metal layers, breakage of a bump can be suppressed, and thus, the yield and the reliability of a semiconductor device can be improved. Further, the columnar bump according to the present invention can be manufactured according to a conventional plating process without increasing the number of the photoresist, and thus, manufacture thereof with a simple process is possible.
[0087] Further, the melting point of the solder as the uppermost layer is lower than that of other solders, and hence the height of the bump can be maintained even after the reflow process. Further, by appropriately determining the amount of the solder as the uppermost layer, the horizontal spread of the bump due to the melted solder can be suppressed, which is effective in decreasing the bump pitch and the chip size. Still further, by appropriately determining the thicknesses (volumes) of the high melting point metal layers and the solder layers, the increase in resistance due to the bump can be suppressed to a minimum. | Provided is a semiconductor device having a bump structure which is capable of resolving inconvenience in mounting. The semiconductor device comprises: an electrode pad; and a columnar bump formed on the electrode pad, the columnar bump comprising: a first high melting point metal layer ( 14 ) formed on the electrode pad; a first solder ( 15 ) formed on the first high melting point metal layer ( 14 ); a second high melting point metal layer ( 16 ) formed on the first solder ( 15 ); and a second solder ( 17 ) which is formed on the second high melting point metal layer ( 16 ) and is connected to an external. | 8 |
BACKGROUND OF THE INVENTION
This invention relates to directional drilling. More particularly, this invention relates to a directional drilling apparatus and process in which a following liner is used.
SUMMARY OF THE PRIOR ART
In conventional vertical drilling, the use of lining pipes circumscribing a drill string in the form of "overshoes" is known. Such overshoes are normally used where a drilling accident occurs and a drill string has a portion of its length broken off in a vertical hole. Typically, the overshoe drilling pipe drills down concentrically about the broken section of drill string at the bottom of the hole. After drilling completely about the broken section of drilling pipe with the overshoe, conventional fishing tools can be used to retrieve the broken section of drill string to unobstruct the original and intended vertical drilling path.
It has heretofore been unknown to use such overshoes in drilling inverted arcuate paths underneath obstacles, as illustrated in my U.S. Pat. No. 3,878,903 for APPARATUS AND PROCESS FOR DRILLING UNDERGROUND ARCUATE PATHS. The purpose of the following liner in this context is to maintain the drilled hole and provide a second larger drill pipe to be used as a production casing or for subsequent reaming of the hole. Accordingly, the invention summarized hereafter is believed to radically distinguish from the known prior art.
SUMMARY OF THE INVENTION
A motor-powered directional drill is advanced in an inverted arcuate path underneath an obstacle such as a water course. A second concentric and larger lining pipe follows the advance of the directional drill either simultaneously but preferably sequentially to form a concentric annulus about the directional drill. This lining pipe preserves the directional drilling path made and prevents the collapse or the erosion of the hole due to manipulation of the directional drill. When the inverted path underneath the obstacle is completed and the liner extends the full length, the liner becomes a large diameter pipe of improved tortional capability which can be used subsequently to ream the hole to full size for placement of a production casing. A specialized drilling rig is provided having one advancing chuck for crowding the directional drill into the ground and another larger rotating chuck to rotate and advance the following lining pipe into the ground concentrically about the directional drill.
OTHER OBJECTS AND ADVANTAGES OF THE INVENTION
An object of this invention is to disclose the use of a following liner to assist a directional drill. According to this aspect, the directional drill is advanced in a leading relation into the ground and manipulated to achieve the desired path. Thereafter, and preferably in sequence behind a directional drill, a following liner is inserted for a portion, but less than all, of the length of the directional drill string in the ground.
An advantage of the following lining pipe is that even when the directional drill string is withdrawn, the directionally drilled hole will stay open in the ground, at least for the length of the following liner.
A further advantage of this apparatus is that columnar failure of the directional drill string along a substantial length of its penetration into the ground is prevented. Where a small diameter pilot string is crowded into the ground, it cannot be subjected to columnar failure and directional deviation for at least that length which is within the following liner.
An additional advantage of the following liner is that when it is placed completely along the length of the directional drilling string, it provides a larger diameter tortionally stronger pipe in the hole. This pipe can be used either as the final production casing or, alternately, can be used for further working of the drilled inverted arcuate path, such as reaming the path into a still larger hole for the placement of a production casing.
Yet another advantage of this invention is that the likelihood of a lost hole is reduced. Where failure of the initial pilot string occurs, either through breaking, sticking or the like, the following liner preserves the drill path made at least insofar as it has penetrated along the drilled path.
A further advantage of the following liner is that it can be used for communication of mud in an annulus about the pilot string either to or from the underground site where pilot string directional drilling is occurring. Cuttings can be returned from the pilot string and examined to optimize the drilling process. The drilling mud, an expensive consumable of drilling processes, can thus be processed and fully recycled. The drilled path along the length of the liner penetration into the earth is flushed clean of drilling mud so that it is fully recovered. Furthermore, the pilot string is provided with completely lubricated movement along this segment of the hole by the mud in the annulus.
A further advantage of the liner is that knifing and resultant sticking of the pilot string in the ground is prevented. Thus, where the pilot string is completely removed to alter its cutting head and thereafter reinserted into the ground, the drilled path does not become elongated in section due to the sliding passage of the drill string. Moreover, the pilot string does not tend to seat and permanently stick into the ground.
A further object of this invention is to disclose a drill rig capable of practicing the disclosed process. According to this aspect of the invention, a drilling apparatus with two discrete chucks is disclosed. The first chuck is used for crowding on a nonrotative basis a motor powered drill and following pilot string into the ground. The second chuck provides for rotation and is mounted concentrically about the pilot string. This latter chuck simultaneously rotates and advances the following liner in a concentric annulus about the pilot string. Provision is made to advance, preferably sequentially, the pilot string and following liner into the ground.
An advantage of the apparatus herein disclosed is that the improved directional process heretofore set forth in my above-referenced patent application can be practiced with this apparatus in its entirety.
A further advantage of this apparatus is that sections of pilot string and liner can be placed in concentric relation and be dropped into the path of the specialized drill rig. According to this aspect, a section of pilot string is placed interiorly of the section of liner. The drill rig is retracted its full length so that both the liner and pilot string can be connected at the ground adjacent end to the string in the ground and at the chuck end to their respective driving chucks. Thereafter, the liner is advanced for the length of the section preferbly followed by the pilot string being advanced for the length of its section. The result is the preferred sequential advance of liner and pilot string in a directional inverted underground arcuate path underneath an obstacle.
Other objects, features and advantages of this invention will become more apparent after referring to the following specification and attached drawings in which:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross sectional elevation view illustrating the operation of the present invention in drilling along an underground inverted arcuate path under an obstacle;
FIG. 2 is an elevation view of the leading end of the apparatus of the present invention illustrated in FIG. 1;
FIG. 3 is an elevation view of the drilling rig of the present invention illustrated in FIG. 1;
FIG. 4 is an enlarged cross sectional view of the drilling head of the present invention;
FIGS. 5A-C are a series of schematic views illustrating the thrusting of the following liner into the ground, crowding of the pilot string into the ground, and insertion of a new following liner/pilot string setup respectively.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The operation of the present invention in drilling along an inverted underground arcuate path is illustrated generally in FIG. 1. In the situation depicted in FIG. 1, it is desired to traverse a water course 10, drilling from a first position 12 on the surface of the ground at one side of the water course to a second position 14 beyond a structure 16 at the other side. The desired path is illustrated generally by dashed line 18, and can comprise either a constant radius arc or a path of complex curvature. A pilot hole is dilled along path 18 by a directional drill 20 powered through a trailing drill string 22 which extends through the drilled hole and exits at position 12. Directional drill 20 can be controlled according to the principles set forth in my U.S. Pat. No. 3,878,903 for "APPARATUS AND PROCESS FOR DRILLING UNDERGROUND ARCUATE PATHS." Other directional drilling techniques could be used as well.
The present invention provides a following liner 24 extending from a position substantially behind directional drill 20 to the entrance 12 to the drilled hole. Following liner 24 has a larger diameter than drill string 20 so that the following liner will fit circumferentially around the drill string within the hole. During the drilling along arcuate path 18, a survey tool is periodically inserted within drill string 22 to a position immediately behind directional drill 20 to determine the current position of the directional drill. This survey tool utilizes magnetic compasses to obtain such readings, and it is necessary to have following liner 24 trail directional drill 20 for a sufficient length so that it will not interfere with the operation of the survey tool, usually by drilling the pilot hole for some distance before beginning to insert the liner. However, when directional drill 20 is to be withdrawn from the hole, such as for replacement of the drill bit, following liner 24 will maintain a substantial portion of the hole and it will no be lost. Upon reinsertion of the drill, the drill string will pass freely along liner 24 and will not seat and become stuck in the hole. Maintaining the hole is especially critical in soft sand or loose mud, as often found underneath a water course such as 10.
At the entrace position 12 of the drilled hole into the ground, an inclined drill rig 26 is positioned in a slanted hole 28. The forward surface 30 of hole 28 is normal to the initial direction of the path into the ground for ease in drilling the hole. A large diameter pipe 32 projects through surface 30 so that it is not eroded during the drilling process.
The leading end of the drilling apparatus illustrated in FIG. 1 is shown in more detail by way of reference to FIG. 2. Directional drill 20 has a leading drill bit 40 powered by drilling mud supplied through drill string 22. As drill bit 40 dislodges and scarifies the earth along the desired arcuate path, these cuttings are entrained in the drilling mud which flows backwardly in the small annular space 42 surrounding drill string 22. Following liner 24 is provided with a cutting edge 44 at its leading end to ream the hole to a larger diameter for accommodating the liner. The inner diameter of liner 24 is preferably greater than the outer diameter of drill string 22 so that an annulus 46 is provided therebetween. The drilling mud and the cuttings entrained therein are collected in annulus 46, and will lubricate the passage of drill string 22 within liner 24. The cuttings are allowed to settle out of the drilling mud at the entrance and the drilling mud can be reused.
The drill rig 26 of the present invention is illustrated in more detail in FIG. 3. Drill rig 26 includes an inclined ramp 50 mounted to the lower surface of hole 28. A drill head 52, which will be illustrated in more detal hereinafter, is mounted on carts 54, 55 which ride along ramp 50. A rotatable chuck 56 is mounted at the leading end of cart 54 and is adapted to connect to following liner 24 for simultaneously rotating and thrusting the following liner into the ground as illustrated by arrow 58. A T-fitting 60 is mounted rearwardly of drill head 52 on cart 55. T-fitting 60 is connected to drill head 52 by a bell-shaped connection 62 which allows for rotation of the drill head relative to the T-fitting.
Drilling mud for powering the directional drill is supplied to T-fitting 60 through conduit 64 as illustrated by arrow 66. This drilling mud flows into the interior of drill head 52 and is forced through the drill string and operates a mud-driven motor in the directional drill. Used drilling mud flows out of large diameter pipe 32 and also out of the annulus between drill string 22 and liner 24 to collect in a pool 68 at the bottom of hole 28. The cuttings are allowed to settle out of pool 68, and the used drilling mud can be recycled through conduit 70 as illustrated by arrow 72 which leads to a pump which supplies the drilling mud back through conduit 64 for powering the directional drill.
The construction of drill head 52 is illustrated in more detail by way of reference to the expanded view of FIG. 4. Drill head 52 has a relatively large diameter, forwardly mounted chuck 56 adapted to connect to the trailing end of the following liner, illustrated in phantom at 24. Chuck 56 has a hollow interior open at its leading and trailing ends. In order to thrust following liner 24 downwardly into the ground, it is connected to chuck 56 which will be rotated as will be discussed hereinafter. In order to crowd the drill string into the ground, illustrated in phantom at 22, a second smaller chuck 80, also having a hollow interior, is attached to chuck 56 and is in turn connected to the trailing end of the drill string. Smaller chuck 80 is removed when following liner 24 is to be thrust into the ground.
Rotatable chuck 56 is attached to a sprocket 82 by bolts 84, 85. Sprocket 82 is driven by a chain 86 powered by a drive sprocket 88 (illustrated in FIG. 3) to rotate following liner 24 as it is thrust into the ground. When drill string 22 is to be crowded into the ground, sprocket 82 is ordinarily maintained stationary so that drill string 22 is not rotated. Drive sprocket 82 can be used to alter the azimuth of drill string 22 for controlling the directional drill according to the teachings of my above-identified copending patent application.
Chuck 56 includes a cylindrical portion 88 extending rearwardly from the leading end of the chuck. A bell-shaped housing 90 is mounted to the aft end of circular portion 88 and mates with T-fitting 60. When drill string 22 is to be crowded into the hole, a cap 94 is placed over the aft end of T-fitting 60, and drilling mud is supplied to the fitting through conduit 64 as illustrated by arrow 96. The drilling mud passes through the hollow interiors of chucks 56 and 80 and into drill string 22 to power the drill. When following liner 24 is being thrust into the hole, cap 94 is removed so that drill string 22 can project completely through chuck 56 and exit at the aft end.
The preferred sequential operation of the apparatus of the present invention is illustrated by FIGS. 5A-C in series in which the hole is partially drilled and lined. Initially, a setup including a following liner segment 90, circumscribing a drill string segment 92, is lowered over ramp 50. Segment 90 of the following liner is connected to the trailing end of the liner 24 to extend the length of the liner and drill string segment 92 is attached to the trailing end of drill string 22 to lengthen the drill string. The trailing end of liner segment 90 is connected to large diameter chuck 56 on drill head 52. The smaller chuck 80 and the cover 94 illustrated in FIG. 4 are removed.
After following liner and drill string segments 90 and 92 have been connected to drill heads 52 and 60, drill head 52 is motivated downwardly along ramp 50 as illustrated by arrow 94 in FIG. 5B to thrust following liner 24 into the hole. Chuck 56 is simultaneously rotated to facilitate movement of the liner through the ground. The position of drill string 22 remains unchanged during the thrusting of the liner and projects through drill head 52. A support 96 is provided so that drill string segment 92 does not contact the drill head.
After segment 90 of following liner 24 has been thrust into the ground, drill head 52 is returned to the aft end of ramp 50. The second smaller chuck 80 is attached to larger chuck 56, and the trailing end of drill string segment 92 is attached to the smaller chuck. Also, cap 94 is attached to the trailing end of T-fitting 60. Drill head 52 is then motivated downwardly along ramp 50 to crowd the drill string into the ground. Chuck 56 is ordinarily not rotated during this operation except to control the azimuth of the drill string. Drilling mud is supplied to T-fitting 60 through conduit 64 so that the drilling mud is forced through the drill string to power the directional drill.
Following the advancement of drill string segment 92 and following liner 90 into the ground, a new setup 100 consisting of a new following liner segment 102 circumscribing a new drill string segment 104 is ready to be lowered in place by hoist 106. Drill head 52 is returned to the aft end of ramp 50 so that the new following liner and drill string segments can be attached to the following liner and drill string respectively, and thereafter advanced into the ground to continue the drilling operation.
While the preferred embodiment of the present invention has been illustrated in detail, it is apparent that modifications and adaptations of that embodiment will occur to those skilled in the art. For example, it is apparent that a drill head could be devised in which the drill string segment and the following liner segment are simultaneously thrust into the hole. However, it is to be expressly understood that such modifications and adaptations are within the spirit and scope of the present invention, as set forth in the following claims. | A motor-powered directional drill is advanced in an inverted arcuate path underneath an obstacle such as a water course. A second concentric and larger lining pipe follows the advance of the directional drill either simultaneously but preferably sequentially to form a concentric annulus about the directional drill. This lining pipe preserves the directional drilling path made and prevents the collapse or the erosion of the hole due to manipulation of the directional drill. When the inverted path underneath the obstacle is completed and the liner extends the full length, the liner becomes a large diameter pipe of improved tortional capability which can be used subsequently to ream the hole to full size for placement of a production casing. A specialized drilling rig is provided having one advancing chuck for crowding the directional drill into the ground and another larger rotating chuck to rotate and advance the following lining pipe into the ground concentrically about the directional drill. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This is a Divisional Application of U.S. Ser. No. 11/209,272 filed on Aug. 22, 2005, which is a Continuation-In-Part of U.S. Ser. No. 11/187,092 (now issued as U.S. Pat. No. 7,229,670).
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not applicable
INCORPORATION-BY-REFERENCE OF MATERIAL SUBMITTED ON A COMPACT DISC
[0003] Not applicable
BACKGROUND OF THE INVENTION
[0004] 1. Field of the Invention
[0005] The present invention relates generally to articles of apparel and methods for making the same. More particularly, the invention concerns an improved glove having a multiplicity of strategically located gripping dots formed thereon.
[0006] 2. Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 1.98
[0007] Gloves of various constructions have been suggested in the past and have been used for work and for numerous recreational activities such as driving, shooting, ice-skating, skiing, motorcycling and a wide variety of indoor and outdoor activities. Typically, such gloves are made from leather as well as several different types of treated, relatively hard surfaced fabrics. Attempts have also been made in the past to produce knitted gloves that will enable the user to securely grip and efficiently manipulate various types of articles. While a number of different designs of knitted gloves have been suggested, most are not well suited for conducting many types of sporting activities and for manipulating various types of articles.
[0008] Knit gloves made on modern automatic glove knitting machines are generally produced in an ambidextrous or symmetrical pattern. However, once gripping dots have been applied to one side of the glove, the glove is no longer ambidextrous and instead becomes hand specific. When wearing a glove made in accordance with this method, undesirably the printed area on the thumb portion of the glove does not completely oppose the printed area on the index finger portion of the glove. It is this problem that the present invention seeks to overcome by providing a novel method for applying gripping dots to the knitted glove in a manner to ensure that the gripping dots imprinted on the thumb portion of the glove properly align with the gripping dots imprinted on the index finger portion of the glove.
[0009] One prior art, fully waterproof glove construction is described in U.S. Pat. No. 5,655,226 issued to the present inventor. This glove, which is slightly more bulky than the gloves of the present invention, comprises a three-ply glove construction with the inside and outside plies being knit and the intermediate ply being made from an elastomeric polyurethane film. The three plies are uniquely bonded together using a pliant, waterproof adhesive. The glove described in the '226 patent is not only waterproof but is also breathable so that water vapor from perspiration can be transmitted from inside to outside. For activities that do not require that the glove be absolutely waterproof, the glove of the present invention provides an attractive alternate.
[0010] As will be better understood from the description that follows, the novel glove of the present invention is provided with gripping dots on the palm portion of the glove and on opposing surfaces of the thumb portion of the glove so that when the glove is in position on the hand of the user and when the thumb and index finger are moved together, the grip dots located on the index finger of the glove will engage the grip dots located on the thumb portion of the glove. With this unique construction, the ability of the user to grip and manipulate a variety of differently configured objects and particularly to grip and manipulate objects between the thumb and the index finger is greatly enhanced. Additionally, the glove of the invention is durable, easy to don and comfortable to wear.
BRIEF SUMMARY OF THE INVENTION
[0011] It is an object of the present invention to provide an improved glove that significantly enhances the ability of the user to grip and manipulate a variety of differently configured objects and particularly to grip and manipulate objects between the thumb and the index finger.
[0012] Another object of the invention is to provide an improved glove of the aforementioned character that is easy to don and comfortable to wear.
[0013] Another object of the invention is to provide a glove of the character described in the preceding paragraphs that exhibits a multiplicity of elastomeric gripping dots on the palm side of the glove and on both sides of the thumb portion of the glove to enable the user to securely grip and manipulate various types of articles.
[0014] Another object of the invention is to provide a method of making a glove of the character described in the preceding paragraphs which is simple and straightforward, does not require the use of complicated equipment such as sewing and seaming equipment and can be performed by unskilled workmen with a minimum of training.
[0015] Another object of the invention is to provide a glove as described in the preceding paragraphs that is of simple construction and is easy and inexpensive to manufacture.
[0016] By way of summary, one form of the method of the invention for making the glove comprises the steps of knitting a knitted glove that includes a palm surface and an opposing back surface and then placing the knitted glove over a generally hand-shaped mandrel having a palm portion and a thumb portion to form a knitted glove assembly. With the glove in position over the mandrel, the thumb portion of the knitted glove is rotated about the thumb portion of the generally hand-shaped mandrel to expose front and back surfaces of thumb portion. A specially constructed stencil having a multiplicity of apertures therethrough is then placed over the knitted glove assembly. Next, a multiplicity of dots of a curable polymer emulsion, such as a polyvinyl chloride emulsion, are deposited on the palm surface of the stretched knitted glove and on the now exposed front and back surfaces of the thumb portion by forcing the emulsion through the apertures formed in the stencil to form an uncured first precursor. Then, using an appropriate curing means, the multiplicity of dots of the curable polymer emulsion deposited on the glove are cured to form a cured precursor. Finally, the cured precursor is removed from the mandrel.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)
[0017] FIG. 1 is a generally perspective view showing a knitted glove emplaced over the generally hand-shaped form, or mandrel of the apparatus of the invention.
[0018] FIG. 2 is a generally perspective, exploded view showing the stencil component of the apparatus of the invention superimposed over the assemblage shown in FIG. 1 .
[0019] FIG. 3 is a generally perspective, diagrammatic view showing the curing or irradiation means of the apparatus of the invention superimposed over the assemblage of FIG. 1 as it appears following the deposition of a multiplicity of gripping dots on the palm surface of the stretchable glove.
[0020] FIG. 4 is a generally perspective view of a knitted glove of FIG. 3 having the cured gripping dots printed on the palm surface of the glove and on one surface of the untwisted thumb portion of the glove and illustrating the mismatch of the grip dot pattern on the thumb and the index finger portions of the glove.
[0021] FIG. 5 is a top plan view illustrating a glove stretched over an aluminum mandrel with the thumb portion of the glove having been rotated about the thumb portion of the mandrel in accordance with the method of the present invention and showing the stencil component of the apparatus of the invention superimposed over the twisted thumb assemblage.
[0022] FIG. 6 is a generally perspective, diagrammatic view showing the curing or irradiation means of the apparatus of the invention superimposed over the assemblage of the lower portion of FIG. 5 as it appears following the deposition of a multiplicity of gripping dots on the palm surface of the stretchable glove and on the opposing surfaces of the twisted thumb portion of the glove.
[0023] FIG. 7 is an enlarged fragmentary plan view of the twisted thumb portion of the imprinted glove illustrating the imprinting of the gripping dots on the opposing surfaces of the thumb portion of the glove.
DETAILED DESCRIPTION OF THE INVENTION
[0024] Referring to the drawings and particularly to FIGS. 1 , 2 and 3 , one form of the apparatus of the invention for making an improved gripping glove is there illustrated. In the present form of the invention, the apparatus comprises a substantially rigid, aluminum form 14 , which has the general shape of a human hand. Form, or mandrel 14 has a first, generally planar surface 16 and a second, spaced-apart generally planar, opposing surface 18 .
[0025] Also forming a part of the apparatus of the present invention is substantially rigid stencil component 20 that has generally planar, spaced-apart opposing surfaces 20 a and 20 b . As seen in FIG. 2 stencil 20 is provided with a multiplicity of spaced-apart generally dot size apertures 22 therethrough.
[0026] Turning to FIG. 3 , it can be seen that the apparatus of the invention also includes curing, or irradiation means, generally designated by the numeral 23 , for irradiating the precursor assemblies of the invention. The character of this important irradiation means will presently be described.
[0027] By way of illustration, FIGS. 1 and 2 show a method of making a gripping glove, such as that illustrated in FIG. 4 , in which the gripping dots on the index finger of the printed glove misalign with the gripping dots provided on the thumb portion of the glove. In this example, the knitted glove has been emplaced over the mandrel 18 in the manner shown in FIG. 1 with the thumb portion 27 of the glove in a non-rotated, or non-twisted configuration. With the glove in this position, a multiplicity of dots of a polymer emulsion, such as a polyvinyl chloride emulsion, can be deposited on the palm surface 25 a of the glove and on the exposed surface 27 a of the non-rotated thumb portion of the glove by forcing the emulsion through the apertures 22 that extend through the stencil. The dots of polymer thusly deposited can then be cured using the curing means 23 illustrated in FIG. 3 of the drawings to produce the glove construction illustrated in FIG. 4 of the drawings wherein the gripping dots exhibit a rubber-like consistency. As illustrated in FIG. 4 , when the index finger of the glove is moved into engagement with the thumb portion of the glove the gripping dots on the index finger undesirably misalign with the gripping dots on the thumb portion of the glove making it difficult to grip and manipulate articles between the thumb and index finger. It is this deficiency of the glove made in accordance with the method illustrated in FIGS. 1 , 2 and 3 that the novel method of the present invention seeks to overcome.
[0028] Turning to FIGS. 5 through 7 of the drawings, the method of the present invention that overcomes the deficiency discussed in the preceding paragraph is there illustrated. The first step in this novel method is to knit, in a conventional manner well understood by those skilled in the art, a knit glove comprising a hand covering portion having a palm portion, a thumb portion and an index finger portion. Preferably, the glove, is knitted using a readily commercially available stretchable fiber. The knit glove thus formed is then emplaced over the mandrel 14 with the palm side 25 a facing up. Next, as illustrated in FIG. 5 , the thumb portion of the glove is rotated relative to the thumb portion of the mandrel so that the back portion of the thumb surface 27 is now positioned on the front side of the mandrel.
[0029] With the glove in position over the form 14 , the next step in the method of the invention is to superimpose the stencil 20 over the palm and twisted thumb portions of the glove in the manner illustrated in FIG. 5 . With the stencil 20 indexedly aligned with the glove, a multiplicity of dots 28 of a polymer emulsion, such as a liquid vinyl emulsion ( FIG. 6 ), are deposited on the palm and twisted thumb surfaces of the stretched glove by forcing the emulsion through the apertures 22 to form an uncured precursor. After the polymer emulsion is forced through the apertures 22 through the use of a squeegee or any other suitable instrumentality (not shown), the dots 28 that are formed are converted from a paste-like consistency into a rubber-like, semi-rigid consistency and are temporarily bonded to the surfaces 25 a and 27 .
[0030] Following the dot formation step to form the uncured precursor 31 , the polymer dots, such as the polyvinyl chloride emulsion dots 28 are suitably cured. This curing (fusing or conversion) of the dots may be done by exposing the uncured dots to a suitable radiation such as is emitted from the radiation means, or irradiation device 23 of the invention (see FIG. 6 ). The radiation means can comprise either an irradiation device that produces infrared heat or an irradiation device that produces ultraviolet light depending on the formulation of the emulsion. When certain emulsions are used, the radiation means can also comprise a conventional heating means for controllably heating the uncured emulsion. Radiation means, such as device 23 , are well known to those skilled in the art and are readily commercially available.
[0031] It is to be understood that in practice the uncured precursor 31 could be positioned on a conveyor belt and passed beneath the irradiation means in a manner to cure the dots 28 .
[0032] Following the curing step, the glove is removed from the form 14 . As depicted in FIG. 7 when the printed glove 37 is removed from the form, the dots provided on the surfaces of the thumb portion of the glove effectively align with the dots provided on the surfaces of the index finger portion of the glove. The unique grip dot pattern provided on the finished glove provides improved gripping characteristics both when the glove is wet and when the glove is dry compared to the grip obtainable from bare hands. More particularly, the improved glove of the invention significantly enhances the ability of the user to grip and manipulate objects between the thumb and the index finger. The novel dot pattern also makes the finished glove extremely durable and substantially abrasion resistant.
[0033] Having now described the invention in detail in accordance with the requirements of the patent statutes, those skilled in this art will have no difficulty in making changes and modifications in the individual parts or their relative assembly in order to meet specific requirements or conditions. Such changes and modifications may be made without departing from the scope and spirit of the invention, as set forth in the following claims. | An improved glove that significantly enhances the ability of the user to grip and manipulate a variety of differently configured objects and particularly to grip and manipulate objects between the thumb and the index finger. The improved glove exhibits a multiplicity of elastomeric gripping dots on the palm side of the glove and on both sides of the thumb portion of the glove to enable the user to securely grip and manipulate various types of articles. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] Reference is made to Ser. No. 60/155,494, filed Sep. 23, 1999, which is entitled “3D and Higher-dimensional Volume Segmentation via Minimum-cut Algorithms” and hereby incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a method and apparatus for segmenting 3D and higher dimensional images into two subsets in order to locate a part thereof, and in particular, to a method of segmenting without any topological restriction on the resultant subsets.
[0004] 2. Description of Related Art
[0005] A situation often occurs that a multi-dimensional array that assigns data to each multi-dimensional slot (voxel) is given and a need arises to partition the set of voxels into two or more subsets according to the data.
[0006] For instance, it is well known to obtain three-dimensional arrays of data representing one or more physical properties at regular grid positions within the interior of solid bodies. Such data may be obtained by non-intrusive methods such as computed axial tomography (CAT) systems, by magnetic resonance imaging (MRI) systems, or by other non-intrusive mechanisms such as ultrasound, positron emission tomography (PET), emission computed tomography (ECT) and multi-modality imaging (MMI). Each of these techniques produces a planar, grid-like array of values for each of a succession of slices of the solid object, thus providing a three-dimensional array of such values. Typically, the solid object is a human body or a portion thereof, although the method is equally applicable to other natural or artificial bodies. In the case of CAT scanning, the physical value is the coefficient of x-ray absorption. For MRI, the physical values are the spin-spin and the spin-lattice relaxation echoes. In any event, the measured physical values reflect the variations in composition, density or surface characteristics of the underlying physical structures.
[0007] It is likewise known to utilize such three-dimensional arrays of interior physical values to generate visual images of the interior structures within the body. In the case of the human body, the visual images thus produced can be used for medical purposes such as diagnostics or for the planning of surgical procedures. In order to display two-dimensional images of such three-dimensional interior structures, however, it is necessary to locate the position of the boundary of such structure within the array of physical values. A significant problem in displaying such internal surfaces is, therefore, the need to segment the data samples into the various tissues. This has been accomplished in the prior art by simply deciding the structure to which each voxel belongs by comparing the data associated to the voxel to a single threshold value, or to a range of threshold values, corresponding to the physical property values associated with each structure or its boundary. Bones or any other tissue, for example, can be characterized by a known range of density values to which the array values can be compared. Such simple thresholding, however, is too susceptible to noise. That is, at the boundary, voxels with values near threshold can be swayed either way by a smallest noise, giving very noisy result. What is needed is to incorporate the tendency of nearby voxels to belong to the same partition.
[0008] Domains of applications of segmentation other than medical applications include graphics, visualization tools, and reconstruction of 3D objects. In graphics, it is known to segment an object from an image. When there is a sequence of image (video), it can be considered a 3D image. Thus a segmentation of moving object from a video sequence is an application of 3D segmentation.
[0009] Also, the data array is not limited to 3D. Higher dimensional applications include four-dimensional segmentation of a temporal sequence of 3D images, such as a 3D image of beating heart.
[0010] It is important in many applications that the resultant sets of voxels are not restricted in the number of connected component. Indeed, it is generally necessary to be able to automatically choose the appropriate number of connected components. Moreover, for a larger class of applications, the subsets should have no topological restrictions at all. For instance, each connected component should be allowed to have as many holes as appropriate to fit the data. Conventional methods have at least one of the following three shortcomings: they either i) have topological restrictions on the solution, ii) are not guaranteed to reach the optimal solution, or iii) need user help or intervention. Some methods presuppose the nature of the set to be found. For instance, if arteries are expected, some methods try to find one-dimensional object with some thickness, making it difficult to find bifurcating arteries. An algorithm that has desirable topological properties is suggested in [O. Faugeras and R. Keriven. “Complete Dense Stereovision Using Level Set Methods”, in Proceedings of the 5 th European Conference on Computer Vision, Springer-Verlag. LNCS 1406, pp. 379-393, 1998], based on an entirely different method (Level Sets of Evolution Equations). Yet, it is a gradient-descent method with no guarantee to reach the optimal. Region Growing methods, similarly, have good topological properties, but require user intervention to select the regions. Moreover, no Region Growing method is an optimization method, that is, they are not guaranteed to give optimum solutions. Another technique described in [J. Shi and J. Malik. “Normalized cuts and image segmentation.” in Proceedings of the IEEE Conference on Computer Vision and Pattern Recognition 1997, pp. 731-737] uses a graph technique, which approximates the solution (i.e., it is not guaranteed), and perhaps does not have the same topological properties. The present method uses similar technique used in other area, 2D image restoration, described in [D. M. Greig, B. T. Porteous, and A. H. Seheult. “Exact maximum a posteriori estimation for binary images.” Journal of Royal Statistical Society B, 51, pp. 271-279, 1989].
SUMMARY OF THE INVENTION
[0011] Objects and Advantages
[0012] Accordingly, it is an object of the invention to provide a method to automatically segment 3D and higher-dimensional images stored in the memory of a computer system into two subsets without user intervention, with no topological restriction on the solution, and in such a way that the solution is an optimal in a precisely defined optimization criterion, including an exactly defined degree of smoothness.
[0013] In accordance with this and other objects of this invention, a method of segmenting input data representing an image is described in order to locate a part of the image. The input data further comprises voxels. The method stores a graph data structure in the memory of a computer system. The graph data structure comprises nodes and edges with weights, wherein the nodes comprise nodes s, t, and a plurality of voxel nodes. The edges comprise at least one edge from the node s to at least one of the voxel nodes, at least one edge from at least one of the voxel nodes to the node t, and at least one neighbor edge from at least one of the voxel nodes to another of the voxel nodes. The method further comprises the steps of designating one of the voxel nodes as corresponding voxel node for each of the voxels, setting the weights for the edges, partitioning the nodes into at least two groups, one including the node s and another including the node t, by a minimum-cut algorithm, and partitioning the voxels into at least two segments by assigning each of the voxels to the segment corresponding to the group to which the corresponding voxel node for the voxel belongs.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Those mentioned above and other objects and advantages of the present invention will become apparent by reference to the following description and accompanying drawings wherein:
[0015] FIG. 1A schematically shows the first nearest neighbors of a voxel in the case of three dimensions;
[0016] FIG. 1B schematically shows the second nearest neighbors of a voxel in the case of three dimensions;
[0017] FIG. 1C schematically shows the third nearest neighbors of a voxel in the case of three dimensions;
[0018] FIG. 1D schematically shows the first, second and third nearest neighbors of a voxel in the case of three dimensions;
[0019] FIG. 2 illustrates the major steps in the method of present invention;
[0020] FIG. 3A schematically shows the simplest example of the problem;
[0021] FIG. 3B shows the corresponding graph that would be used in the method of present invention to solve the problem shown in FIG. 3A ;
[0022] FIG. 4A through FIG. 4D show the four possible cut of the example graph shown in FIG. 3B ;
[0023] FIG. 5 is a block diagram of an MRI system that may be used in the present invention.
[0024] FIG. 6 is a schematic diagram showing a conceptual organization of the graph G in the case of three dimensions;
[0025] FIG. 7A shows the simplest example to illustrate merging;
[0026] FIG. 7B shows the corresponding graph that would be used in the method of present invention to solve the problem shown in FIG. 7A ; and
[0027] FIG. 7C shows the result of merging two nodes in the graph shown in FIG. 7B .
DETAILED DESCRIPTION OF THE INVENTION
[0028] General Description
[0029] Hereafter, the dimension of the input data is denoted by DIM. For three dimensions, DIM =3.
[0030] Input
[0031] In the segmentation problem that the present invention solves, a DIM-dimensional data structure stored in the memory of a computer system is given as the input to the method, which usually is realized as a computer program. In medical applications, the data is typically acquired by non-intrusive methods such as computed axial tomography (CAT) systems, by magnetic resonance imaging (MRI) systems, or by other non-intrusive mechanisms such as ultrasound, positron emission tomography (PET), emission computed tomography (ECT) and multi-modality imaging (MMI), and stored in the memory of a computer system. The data structure will be called an “image” hereafter, and comprises voxels and neighborhood structure:
i. Each voxel has associated data, such as a number or a set of numbers (vector). Voxels are conceptually laid out in a DIM-dimensional configuration. For instance, a 3D (DIM=3) image can be a simple box of size L×N×M with one voxel for each of L×N×M possible combinations of three integers (l, n, m) for l=1, . . . , L, n=1, . . . , N, and m=1, . . . , M. An image can also be a subset of such a DIM-dimensional box. ii. The neighborhood structure is defined by specifying a small set of “neighbor voxels” for each voxel, according to the application. In other words, it is specified, among all voxels, which voxel is neighboring which other voxels. The specification can be given as a data stored in the memory of a computer system, or it can be given as an implicit assumption in the program that realizes the method of the present invention, i.e., the program may assume a particular arrangement of voxels. The neighborhood structure is symmetric in the sense that if a voxel v is a neighbor of another voxel u, then u is also a neighbor of v. The simplest set of “first nearest neighbors” for a voxel includes 2×DIM nearest voxels given by increasing or decreasing one of DIM coordinate entries by 1. For instance, FIG. 1A conceptually shows the first nearest neighbors of a voxel 11 at coordinate (l, n, m) in a 3D image. Neighbor voxels are 12 at (l−1, n, m), 13 at (l+1, n, m), 14 at (l, n−1, m), 15 at (l, n+1, m), 16 at (l, n, m−1), and 17 at (l, n, m+1). The “second nearest neighbors” are those obtained by changing two of the coordinate entries by 1, and the 3D case is schematically shown in FIG. 1B . Similarly, a k-th nearest neighbor of a voxel v has k coordinate entries that are different by 1 from corresponding entries of v. FIG. 1C shows the third nearest neighbors in the three dimensional case, and FIG. 1D shows the first, second, and third nearest neighbors together in the case of three dimensions. Although such a k-th nearest neighborhood structure is a natural choice, the application of present invention is not limited to this class of neighborhood structures.
[0034] The method partitions the voxels into two complementary subsets S and T, or, equivalently, assigns one of two labels s or t to each voxel. The image will be segmented in the sense that voxels in S, to which label s is assigned, will represent the “interesting” voxels for each particular application, such as voxels corresponding to arteries. It is an advantage of the method of present invention that there is no topological restriction on the resultant subsets. Moreover, our method is completely automatic with no need for user intervention, although the method allows the user to intervene as desired in the process to improve or correct the results of the fully automatic system. The method, while addressed and discussed in depth for the 3D case, can be applied by those skilled in the art to higher or lower dimensions in a straightforward way.
[0035] The criterion as to how the image should be segmented is given by defining a set of numbers:
[0036] a) For each voxel v, a number a(v).
[0037] b) For each neighboring pair of voxels v and u, a nonnegative number b(v, u). Note that b(v, u) and b(u, v) can be different.
[0038] Then, the criterion is that the partition shall be given so that the sum
[0000]
∑
all
v
in
T
all
neighboring
(
v
,
u
)
such
that
v
is
in
S
and
u
is
in
T
a
(
v
)
+
∑
b
(
v
,
u
)
(
1
)
[0000] is minimum over all possible assignments.
[0039] The number a(v) represents the likelihood of v to belong to S. If a(v) is positive, v is more likely to belong to S in an assignment with a minimum sum (1). If it is negative, it is more likely to be in Tin an assignment with a minimum sum (1). The number b(v, u) expresses the likelihood of the boundary coming between v and u in such a way that v is in S and u is in T. It shall be larger if such likelihood is smaller.
[0040] As an example of how these numbers may be selected, suppose that the probabilities
P(v), of the voxel v belonging to S; and P(v, u), for neighboring voxels v and u, of v belonging to S and u belonging to T; are known. Then one possible way is to set
[0000] a ( v )= A log(2 P ( v )),
[0000] b ( v, u )=− B log( P ( v, u )),
[0000] where A and B are some positive numbers. If necessary, infinity in the case of zero probability can be handled in various and well-known ways, for instance by using (P(v)+h)/(1+h) instead of P(v), where h is some small (h<<1) positive number. Some examples of how these numbers may be selected in concrete examples are given in the detailed description of preferred embodiments below.
[0043] Method
[0044] FIG. 2 illustrates the major steps in the method. The main idea of the method is to map the voxels to specially interconnected nodes in a graph. Graphs are used in the art to explain certain ideas clearly; but it is also well known in the art to implement them as a data structures stored in a computer system that can be manipulated by a program. One example of such an implementation is given later in a description of an embodiment.
[0045] A directed graph with edge weights, that is, a graph where each edge has a nonnegative number called a weight associated to it, is created in step 21 . An edge from a node v to another node u is denoted hereafter by an ordered pair (v, u). The graph contains the following:
(a) There is one node for each voxel. This type of node is hereafter called the voxel node corresponding to the voxel, and the voxel node corresponding to voxel v is denoted by the same letter v. (b) There also are two special nodes s and t that correspond to the two labels s and t, respectively. (c) There are edges between voxel nodes. They represent the neighborhood structure between voxels, i.e., voxel nodes corresponding to neighboring voxels are connected by an edge. (d) For every voxel node v, there is an edge (s, v) from s to v and an edge (v, t) from v to t.
[0050] Then, in step 22, nonnegative edge weights are assigned. For each voxel node v, the edge (s, v) has a nonnegative weight w(s, v) and the edge (v, 0 has a nonnegative weight w(v, t). These weights are selected so that the following holds:
[0000] w ( s, v )− w ( v, t )= a ( v ). (2)
[0051] Each voxel node v is also connected to its neighbors. For each neighbor u of v, there are edges (v, u) and (u, v). The edge (v, u) is assigned a weight w(v, u)=b(v, u) and the edge (u, v) is assigned a weight w(u, v)=b(u, v).
[0052] These weights are chosen so that the segmentation criterion exactly corresponds to a condition on a cut of the graph. Here, a cut is a partition of the graph into two parts, one including s and another t, as well known to be often defined in the art. Then, each voxel node belongs to one of the parts, either including s or t. This defines a segmentation of the image: a node that belongs to the same partition as node s is assigned the label s, and a node that belongs to the same partition as node t is assigned the label t. If an edge goes out from the part including s to the one including t, the edge is said to be “cut.” This gives the method an ability to take neighbor interaction into account. There is one-to-one correspondence between partition of nodes and voxels. A score of the assignment (segmentation) is given by the sum of the edge weights that have been cut. The segmentation problem is thus mapped to a problem of finding the “minimum cut”, that is, a cut with the minimum score.
[0053] Thus in step 23 , a minimum-cut algorithm is applied to the graph. Any variant of minimum-cut algorithms, which are well known in the art, are known to solve this problem in polynomial time in the number of nodes and edges in the graph. The method possesses all topological properties as described/required above and can be applied to graphs embedded in any dimension, not only 3D.
[0054] Finally, in step 24 , voxels are segmented according to the cut of the graph. If a voxel node belongs to the same partition as s, the voxel to which it corresponds is assigned the label s and belongs to S. Otherwise, it is assigned the label t and belongs to T. Because of the way that the edge weights are defined, the minimum cut corresponds to the optimal segmentation, that is, it has the minimum sum of equation (1).
[0055] Thus, the method partitions the voxels into two complementary subsets S and T, or, equivalently, assigns one of two labels s or t to each voxel, according to the criterion stated above.
[0056] An Illustration of the Process with the Simplest Example
[0057] Before going into the description of an embodiment, an illustration of the process of the invention by the simplest example is in order.
[0058] FIG. 3A schematically shows the simplest example. Two voxels u and v are shown as 301 and 302 . The two voxels are neighbors of each other, which is indicated by a line segment 303 between them in the figure. Being neighbors means that the two voxels have some tendency to belong to the same partition upon segmentation. The corresponding graph that would be used in the method is shown in FIG. 3B . It has two voxel nodes 304 and 305 corresponding to the voxels 301 and 302 , denoted by the same names u and v, and two additional nodes s ( 306 ) and t ( 307 ). For each of voxel nodes 304 and 305 , there is an edge from s ( 306 ). The edge from s to u, denoted by (s,u), is shown as 308 . Similarly, the edge (s,v) appears in the figure as 309 . There are also two edges from u and v to t ( 307 ), i.e., (u,t) and (v,t), shown as 310 and 311 . There also are edges (u,v) ( 312 ) and (v,u) ( 313 ) between voxel nodes u and v ( 304 and 305 ), representing the neighborhood structure.
[0059] The method finds a cut of the graph. A cut is a partition of the nodes into two groups, containing node s ( 306 ) and t ( 307 ) respectively. FIG. 4A through FIG. 4D show the four possible cut of the example graph shown in FIG. 3B . Two groups are shown as inside (S, containing node s ( 306 )) and outside (T, containing node t ( 307 )) of a dashed curve. Thus in FIG. 4A , only s ( 306 ) is inside and other three nodes are outside. In FIG. 4B , v ( 305 ) is also inside with s ( 306 ), and so on.
[0060] Given a cut of the graph, an edge going out from S to T is said to be cut. Thus, in FIG. 4A , edges (s,u) and (s,v) ( 308 and 309 ), and only these edges, are cut. Each edge has a non-negative number called weight associated with it. The total score of a cut is the sum of weights of all cut edges. Thus, in FIG. 4A , the score of the cut is w(s,u)+w(s,v), where w(s,u) denotes the weight of the edge (s,u).
[0061] Note that one of, and only one of, the edges (s,u) ( 308 ) and (u,t) ( 310 ) is always cut. In FIG. 4A and FIG. 4B , (s,u) ( 308 ) is cut and (u,t) ( 310 ) is not; in FIG. 4C and FIG. 4D , (s,u) ( 308 ) is not cut and (u,t) ( 310 ) is. It is easy to see that (s,u) ( 308 ) is cut whenever u ( 304 ) belongs to T and (u,t) ( 310 ) is cut when it belong to S. Now, since the weights of these two edges are set so that
[0000] w ( s, u )− w ( u, t )= a ( u )
[0000] (see equation (2) above,) the contribution of the two edges to the total score of the cut is a(u) more when u ( 304 ) belongs to T than when it belongs to S. Similarly, the weight contribution from edges (s, v) ( 309 ) and (v, t) ( 311 ) is larger by a(v) when v ( 305 ) belongs to T than when it is in S. Thus, compared to the state when all voxel nodes are in S, that is, the state of FIG. 4D , the sum of the weights of cut edges from s to voxel nodes and those from voxel nodes to t is larger by exactly
[0000]
∑
all
x
in
T
a
(
x
)
.
[0000] Note that a(x) can be either negative or positive number, or zero, for any voxel node x, though the weights must be nonnegative. Since the method finds the cut with the least score, a(x) should be negative if x is likely to belong to T, or positive if it is likely to belong to S, according to the local data for the voxel x.
[0062] The edges (v,u) ( 313 ) and (u,v) ( 312 ) between the voxel nodes u and v ( 304 and 305 ) are not cut when the two nodes belong to the same partition, as in FIGS. 4A and 4D . When one of the nodes u and v ( 304 and 305 ) is in S and another in T, one of the edges (v,u) ( 313 ) and (u,v) ( 312 ) is cut. In FIG. 4B , the edge (v,u) ( 313 ) is cut, that is, it goes from within S out to T, while the edge (u,v) ( 312 ) is not cut since it goes from outside into S. Ordinarily, the weight for the two edges can be set to the same value. Then, the contribution from the two edges to the total score depends only on whether the two voxel nodes belong to the same partition or not. If it is desirable, however, the two cases where u and v are separated (u in S and v in T as in FIG. 4C , or u in T and v in S as in FIG. 4B ) can have different contributions, by letting the weights w(u,v) and w(v,u) have different values. Since the method looks for a cut with smaller total score, an edge with a smaller weight tends to be cut. Thus, if these weights are set relatively large, the two nodes tend to stay in the same partition. This gives the method a tendency to prefer a more smooth solution.
[0063] When the method finds the minimum cut, it resolves a trade-off. The likelihood of individual voxels to belong to either partition is given by the number a(u) and a(v) . If both u and v are more likely to belong to S or T, there is no conflict; both would belong to the same partition, and result would be either like FIG. 4A or FIG. 4D . Or if the voxels have no tendency to stay in the same partition, that is, if the weights w(u,v) and w(v,u) are zero, again there is no conflict and each voxel can belong to the partition to which it tends to belong. If, however, neither are the case, there is a trade-off to be resolved. Although it is a trivial problem in this simplest example, it is in general a very difficult problem to solve.
[0064] An Embodiment of the Invention—MRI image segmentation
[0065] The method of present invention is described here in more details as may be utilized in the segmentation of arteries from MRI. Note that other non-intrusive imaging systems such as computed axial tomography (CAT) systems, ultrasound, positron emission tomography (PET), emission computed tomography (ECT) and multi-modality imaging (MMI), can also utilize the present segmentation method.
[0066] A Magnetic Resonance Imaging (MRI) system examines a tissue type of the human body by applying a gradient magnetic field of varying intensities to the human body, to thereby display the arrangement of nuclear spins of bodily tissue. That is, when a radio frequency (RF) pulse wave within a strong static magnetic field is applied to the human body, the nuclear spins of bodily tissue are excited and nuclear magnetic resonance (NMR) signals are generated when the gradient magnetic field appropriate for bodily tissue is applied. By tuning various parameters such as frequency, sequence and encoding of the RF pulse and magnetization angle; and measuring properties of the NMR signals such as intensity and relaxation time; the system gathers data that can then be processed by computer. The data is generally applied projection reconstruction techniques to give information about the type of bodily tissue at different spatial positions.
[0067] FIG. 5 is a block diagram of an MRI system that may be used in the present invention. The system comprises a magnet 501 , gradient coils 502 , RF coils 503 (the RF coils should be scaled to the anatomy of interest), transmitter 504 , RF power amplifier 505 , gradient amplifier 506 , receiver 507 , digitizer 508 , computer 509 , display interface 510 , scan operation interface 511 , image display terminal 512 , camera 513 and data store 514 . The computer 509 is programmed to acquire and segment data in order to find anatomies of interest in accordance with the above-described methods.
[0068] Here, it is assumed that such a data is given in the form of a 3D data structure, stored in the memory of a computer system, that gives a set of data that characterizes the tissue-type at each voxel. Although this data, which hereafter is called an MRI response, is not necessarily described in simple terms, it is well known in the art how to process and generate such data. (Reference is made to [W. Orrison, J. Lewine, J. Sanders, and M. Hartshorne. Functional Brain Imaging , Mosby-Year Book, St Louis, 1995.1])
[0069] It is common in the art that such MRI response at each voxel is reduced to a number such that a particular number or a range of numbers correspond to a specific tissue type, so that a 2D array of such numbers as gray-scale intensity representing a cross-section of bodily-tissue can be displayed on a screen to be examined by a doctor. Accordingly, it is assumed here that the MRI response is given as a number at each voxel. However, it may be desirable depending on application that such MRI response at each voxel is given as more complex data such as a vector that, for instance, represents responses of the tissue to more than one parameter setting in the MRI process.
[0070] Here, as the input, the data structure is given as an L×N×M array D of double precision floating-point numbers. By specifying a voxel coordinate (l, n, m), the MRI response value D[l, n, m] can be accessed, where coordinate l runs from 1 to L, coordinate n runs from 1 to N, and coordinate m runs from 1 to M. Here, the 3D structure of the voxels directly corresponds to the physical 3D structure. The value at each voxel is an MRI response of the tissue at physical position (l×d 1 , n×d 2 , m×d 3 ) in some Cartesian physical coordinate system, where the physical distance between center of voxels to the three orthogonal directions are denoted by d 1 , d 2 , and d 3 . That is, the physical distance between “physical” voxel (l, n, m) and (l+1, n, m) is d 1 , between (l, n, m) and (l, n+1, m) d 2 , and between (l, n, m) and (l, n, m+1) d 3 .
[0071] As described above, the numbers due to MRI response have direct connection to the physical process of MRI. Different tissues, such as muscle, blood, brain matter, or bone, respond differently to MRI and yield different values. Here, a segmentation of artery is desired and it is assumed that a range (d min , d max ) of MRI response value signifies artery. That is, it is assumed here to be known that, if the MRI response value D[l, n, m] falls between d min and d max , the voxel at (l, n, m) is likely to be an artery voxel.
[0072] As the output, this embodiment will produce an L×N×M array B[l, n, m], which signifies the result of segmentation as B[l, n, m]=1 if the voxel at (l, n, m) is artery, and B[l, n, m]=0 if the voxel is non-artery.
[0073] Given the array D, a graph G is constructed. Here, an undirected graph, which is a special case of a directed graph, is used. It is well known in the art how to manipulate data structures on a computer to realize this end. One simple example is given below where an example minimum-cut algorithm is described.
[0074] FIG. 6 shows a conceptual schematic of the graph organization. The set of nodes V comprises two special nodes s and t, and L×N×M voxel nodes corresponding to the voxels. The voxel node that corresponds to the voxel at coordinate (l, n, m) is herein denoted by v[l, n, m].
[0075] The set E of edges comprises the following two kinds of edges:
a) Each node v[l, n, m] is connected to both s and t. The edge connecting v[l, n, m] and s is denoted by e s [l, n, m] and the edge connecting v[l, n, m] to t is denoted by e t [l,n,m]. Hence there are 2×L×N×M edges of this kind. b) Between the voxel nodes, neighboring nodes are connected. Here, in this example, the first nearest neighborhood system is used. Node v[l, n, m] is connected to nodes v[l−1, n, m], v[l+1, n, m], v[l, n−1, m], v[l, n+1, m], v[l, n, m−1], v[l, n, m+1], except when one or more of these six neighbors do not exist because they are out of the coordinate range, in which case only existing ones are connected. For instance, v[1, 2,M] is connected to v[2, 2,M], v[1, 1,M], v[1, 3,M], and v[1, 2, M−1], since v[0, 2, M] and v[1, 2, M+1] do not exist. The edge connecting v[l, n, m] and v[l+1, n, m] is denoted by e 1 [l, n, m]; the edge connecting v[l, n, m] and v[l, n+1, m] is denoted by e 2 [l, n, m]; and the edge connecting v[l, n, m] and v[l, n, m+1] is denoted by e 3 [l, n, m]. Then there are 3×L×N×M (L×N+N×M+L×M) edges of this kind.
[0078] Each edge has a nonnegative weight, that is, a double precision floating point number equal to or greater than zero. Hereafter the weight for edge e is denoted by w(e). For instance, edge e 3 [2,3,4] that connects v[2,3,4] and v[2,3,5] has the weight w(e 3 [2,3,4]).
[0079] The weights of the edges are determined as follows.
a) The weights for the edges connecting voxel nodes to s and t are set as
[0000] w ( e s [ l, n, m ])=( d max −d min ) 2
[0000] w ( e t [ l, n, m ])=( d min +d max −2× D[l, n, m ]) 2 .
The reader will note that, in (2), these weights correspond to a(v[l, n, m])=w(e s [l, n, m])−w(e t [l, n, m])=4(d max −D[l, n, m])(D[l, n, m]−d min ), which is 0 if D[l, n, m] equals to d min or d max , positive if D[l, n, m] is between d min and d max , and negative if D[l, n, m] is outside of the range [d min , d max ]. Thus, according to the definition, it makes it more likely that the voxel be classified as artery if the value falls between d min and d max . b) The weight for the edges connecting neighboring nodes are set as
[0000] w ( e 1 [ l, n, m ])= K/d 1 ,
[0000] w ( e 2 [ l, n, m ])= K/d 2 , and
[0000] w ( e 3 [ l, n, m ])= K/d 3 , where K is a positive constant that governs smoothness of the segmentation. Resulting sets are smoother if K is larger. These correspond to
[0000] b ( v[l, n, m], v[l+ 1 , n, m ])= b ( v[l+ 1 , n, m], v[l, n, m ])= K/d 1 ,
[0000] b ( v[l, n, m], v[l, n+ 1 , m ])= b ( v[l, n+ 1 , m], v[l, n, m ])= K/d 2 , and
[0000] b ( v[l, n, m,], v[l, n, m+ 1])= b ( v[l, n, m+ 1 ], v[l, n, m ])= K/d 3 ,
[0000] respectively.
[0084] Having set all the data needed to define a graph, a minimum-cut algorithm is applied to the graph. A minimum-cut algorithm divides the set of nodes into two parts so that s and t are separated. This division is called a cut of the graph. The algorithm moreover finds such a cut with the minimum value, where value of a cut is the sum of all the weights of edges whose ends lie in different parts according to the division.
[0085] Several minimum-cut algorithms are known, most of which use maximum-flow algorithm. All these algorithms give an identical results, hence which algorithm to use can be decided by reasons independent from the present invention. Also, there are known some approximation algorithms, such as the one described in [D. Karger. “A new approach to the minimum cut problem”, Journal of the ACM, 43(4) 1996]. These are not guaranteed to give the minimum, but some cut that is close to the minimum. These can also be used for the present invention, and herein called minimum-cut algorithms. An example of minimum cut algorithm is given below.
[0086] Given the result of the minimum-cut algorithm, the output values B[l, n, m] for all l, n, and m are set as follows:
If node v[l, n, m] belongs to the same part as s, set B[l, n, m]=1. Otherwise set B[l, n, m]=0.
[0089] Although these specific edge weights are defined here for the sake of concreteness, it is not necessary for the present invention to set the weights of the edges in this precise way. For instance, weight for an edge between neighboring voxel nodes can be set according to the difference of the data value D[l, n, m] between the two voxels so that it becomes greater if the values are closer, making it less likely for the voxels to be divided in different partitions.
[0090] A Minimum-Cut Algorithm
[0091] Here, a simple minimum-cut algorithm that may be used with the present invention is described. It is described as may be used for higher dimensions, although by letting the constant DIM to be 3, it can be directly used with the preceding embodiment.
[0092] Although it is presented in a form similar to a Pascal-like programming language for clarity and concreteness, and is easy to understand by one skilled in the art, it is meant to illustrate the algorithm, not to be used as a program as it is.
[0093] The entry point is the procedure Mincut, which should be called after setting the input variable Size and W as described below. The result would be in the output variable B when it returns. The algorithm uses push-relabel maximum-flow algorithm with global relabeling. (Reference is made to [B. V. Cherkassky and A. V. Goldberg. “On implementing push-relabel method for the maximum flow problem.” In Proceedings of 4 th International Programming and Combinatorial Optimization Conference, 157-171, 1995.])
[0094] Constants
[0095] DIM: Dimension of the space. In the 3D case above, DIM=3.
[0096] Types
[0097] type NodeCoord: An array [0 . . . DIM−1] of integer; DIM-dimensional node coordinate. type EdgeCoord: An array [0 . . . DIM] of integer; edge coordinate.
[0098] type NodeQueue: A queue of NodeCoord;
[0099] Notation:
[0100] For a DIM-dimensional array X, the element X[vc[0], vc[1], . . . , vc[DIM−1]] of X pointed by a NodeCoord vc is abbreviated as X[vc]. Similarly, for a (DIM+1)−dimensional array Y, Y[ec] is a short hand for Y[ec[0], ec[1], . . . , ec[DIM]]. Also, a pair of an integer and a NodeCoord like (1, vc) denotes an EdgeCoord. For instance, if i is an integer and vc is a NodeCoord, Y[i, vc] means the element Y[i, vc[0], vc[1], . . . , vc[DIM−1]].
In the algorithm, NodeCoord vc with vc[0]=−1 signifies the node s, and vc[0]=−2 means the node t. A control structure for all vc do . . . is used to mean to iterate for all NodeCoord in the DIM-dimensional hypercube specified by Size (an input variable defined below.) For instance, in the 3D example above, this means to iterate for all L×N×M combination of coordinates.
[0103] Auxiliary Routines
procedure Enqueue (vc: NodeCoord; var Q: NodeQueue);: pushes vc in the back of the queue Q. function Dequeue (var Q: NodeQueue): NodeCoord;: pops a NodeCoord vc from the queue Q and return vc. function Empty (var Q: NodeQueue): bool;: returns true if the queue Q is empty.
[0107] Input
Size: NodeCoord; The size of the voxel array. DIM-dimensional vector. W: (DIM+1)−dimensional array of double
W[0, vc]: weight of edge from s to vc W[1, vc]: weight of edge from vc to t W[1+d, vc]: weight of the edge from vc to the neighbor in d-th dimension (the node with the d-th coordinate+1.) In the 3D case, W[0, l, n, m]=w(e s [l,n,m]), W[1, l, n, m]=w(e t [l,n,m]), W[2, l, n, m]=w(e 1 [l,n,m]), W[3, l, n, m]=w(e 2 [l,n,m]), W[4, l, n, m]=w(e 3 [l,n,m])
[0118] Output
B: DIM-dimensional array of integer. B[vc]=0 if the voxel at vc belongs to the same partition as s.
[0120] Global variables
[0121] In addition to Size, W, and B above, global variables are as follows:
es, et: double precision floating point number (double) variables ds, dt, NUMNODE: integer variables curEdgeS, curEdgeT: NodeCoord variables excess: a DIM-dimensional array of doubles. One entry for each voxel. dist, curEdge: DIM-dimensional arrays of integers. One entry for each voxel. F: a (DIM +1)−dimensional array of doubles. The same size as W. Q: NodeQueue; s: NodeCoord. s[0]=−1. t: NodeCoord. t[0]=−2.
[0131] The algorithm
[0000]
function Excess(vc : NodeCoord) : double;
begin
if vc[0] =−1 then Excess ← es
{ node s }
else if vc[0] =−2 then Excess ← et
{ node t }
else Excess ← excess[vc];
end
procedure SetExcess(vc : NodeCoord; e : double);
begin
if vc[0] =−1 then es ← e
{ node s }
else if vc[0] =−2 then et ← e
{ node t }
else excess[vc] ← e;
end
function Distance(vc : NodeCoord) : integer;
begin
if vc[0] =−1 then Distance ← ds
{ node s }
else if vc[0] =−2 then Distance ← dt
{ node t }
else Distance ← dist(vc);
end
procedure SetDistance(vc : NodeCoord; d : integer);
begin
if vc[0] =−1 then ds ← d
{ node s }
else if vc[0] =−2 then dt ← d
{ node t }
else dist(vc) ← d;
end
function Active(vc : NodeCoord) : bool;
begin
if vc[0] < 0 then Active ← false
{ node s or t}
else if (Distance(vc) ≧ 0) and (Excess(vc) > 0) then Active ← true
else Active ← false;
end
function Inc(var vc : NodeCoord) : bool; {Increment for a DIM-dimensional iteration.}
var
d : integer; result : bool;
begin
result ← false;
d← 0;
while (d < DIM) and (result = false) do begin
vc[d] ← vc[d] + 1;
if vc[d] < Size[d] then result ← true
else begin
vc[d] ← 0;
d ← d + 1;
end;
end;
Inc ← result;
end
procedure Reset(var vc : NodeCoord);
var
d : integer;
begin
for d ← 0 to DIM − 1 do vc[d] ← 0;
end
function GetEdge(vc : NodeCoord; var wc : NodeCoord; var ec : EdgeCoord) : integer;
begin
if vc[0] ≧ 0 then begin { node other than s or t.}
ec ← (0, vc);
wc ← vc;
if curEdge[vc] = 0 then begin
ec[0] ← 0;
wc ← s;
result ←−1;
end
else if curEdge[vc] = 1 then begin
ec[0] ← 1;
wc ← t;
result ← 1;
end
else begin
if curEdge[vc] < 2 + DIM then begin
ec[0] ← curEdge[vc];
result ← 1;
end
else begin
ec[0] ← curEdge[vc] − DIM;
ec[ec[0] − 1] ← ec[ec[0] − 1] − 1;
result ←−1;
end;
wc[ec[0] − 2] ← wc[ec[0] − 2] + result;
end;
end
else if vc[0] =−1 then begin
ec ← (0, curEdgeS[d]);
wc ← curEdgeS;
result ← 1;
end
else begin
ec ← (1, curEdgeT[d]);
wc ← curEdgeT;
result ←−1;
end;
GetEdge ← result;
end;
function ProceedEdge(vc : NodeCoord) : bool;
var
i : integer; result, loopout : bool;
begin
result ← true;
if vc[0] ≧ 0 then
repeat begin
loopout ← true;
curEdge[vc] ← curEdge[vc] + 1;
if curEdge[vc] = 2 + 2 × DIM then begin
curEdge[vc] ← 0;
result ← false;
end
else if curEdge[vc] > 1 then begin
i ← curEdge[vc] − 2;
if ((i < DIM) and (vc[i] ≧ Size[i] − 1)) or
((i ≧ DIM) and (vc[i − DIM] = 0)) then loopout ← false;
end;
end until loopout = true
else if vc[0] =−1 then result ← Inc(curEdgeS)
else result ← Inc(curEdgeT);
ProceedEdge ← result;
end;
procedure ResetEdge(vc : NodeCoord);
var
i : integer;
begin
if vc[0] ≧ 0 then curEdge[vc] ← 0
else if vc[0] =−1 then Reset(curEdgeS)
else Reset(curEdgeT);
end
procedure Relabel(vc : NodeCoord);
var
d, dw, mdw, r : integer; rf : double; wc : NodeCoord; ec : EdgeCoord; escape : bool
begin
if Active(vc) = true then begin
d ← Distance(vc);
mdw ←−1;
escape ← false;
repeat begin
r ← GetEdge(vc, wc, ec);
rf ← W[ec] − r × F[ec];
dw ← Distance(wc);
if (rf > 0) and (d > dw) then begin
ResetEdge(vc);
escape = true;
else if rf > 0 then begin
if mdw =−1 then mdw ← dw + 1
else mdw ← min(mdw, dw + 1);
end;
end until (escape = true) or (ProceedEdge(vc) = false);
SetDistance(vc, mdw);
end;
end
procedure PushRelabel(vc : NodeCoord);
var
r : integer; delta, rf : double; wc : NodeCoord; ec : EdgeCoord; wactive : bool
begin
NodeCoord wc;
EdgeCoord ec;
r ← GetEdge(vc, wc, ec);
wactive ← Active(wc);
if (Active(vc) = true) and (Distance(vc) = Distance(wc) + 1) then begin
rf ← W[ec] − r × F[ec];
if rf > 0 then begin
delta ← min(Excess(vc), rf);
F[ec] ← F[ec] + r × delta;
SetExcess(vc, Excess(vc) − delta);
SetExcess(wc, Excess(wc) + delta);
end
else if ProceedEdge(vc) = false then Relabel(vc);
end
else if ProceedEdge(vc) = false then Relabel(vc);
if (wactive = false) and (Active(wc) = true) then Enqueue(wc, Q);
end
procedure Initialize;
var
i : integer; w : double; vc : NodeCoord;
begin
Reset(curEdgeS);
Reset(curEdgeT);
NUMNODE ← 1;
for i ← 0 to DIM − 1 do NUMNODE ← NUMNODE × Size[i];
NUMNODE ← NUMNODE + 2;
ds ← NUMNODE; dt ← 0; es ← 0; et ← 0;
for all vc do begin
w ← W[0, vc];
F[0, vc] ← w;
if w > 0 then Enqueue(vc, Q);
excess[vc] ← w;
dist(vc) ← 0;
curEdge[vc] ← 0;
for i ← 1 to DIM + 1 do F[i, vc] ← 0;
end;
end
procedure BFS(root : NodeCoord; initdist : integer); {Breadth first search in residual graph.}
var
d, r, dw : integer; rf : double; vc, wc : NodeCoord; ec : EdgeCoord; Q2 : NodeQueue;
begin
SetDistance(root, initdist);
Enqueue(root, Q2);
while Empty(Q2) = false do begin
vc ← Dequeue(Q2);
ResetEdge(vc);
d ← Distance(vc);
repeat begin
r ← GetEdge(vc, wc, ec);
dw ← Distance(wc);
if dw =−1 then begin
rf ← W[ec] + r × F[ec];
if rf > 0 then begin
SetDistance(wc, d + 1);
Enqueue(wc, Q2);
end;
end;
end until (ProceedEdge(vc) = false);
end;
end
procedure GlobalRelabel;
var
vc : NodeCoord;
begin
for all vc do SetDistance(vc, −1);
BFS(t, 0);
BFS(s, NUMNODE);
end
procedure FindCut;
var
vc : NodeCoord;
begin
for all vc do SetDistance(vc, −1);
BFS(t, 0);
for all vc do if Distance(vc) =−1 then B(vc) ← true else B(vc) ← false;
end
procedure Maxflow;
var
vc : NodeCoord; c : integer;
begin
Initialize;
while Empty(Q) = false do begin
vc ← Dequeue(Q);
d ← Distance(vc);
repeat PushRelabel(vc) until (Excess(vc) = 0) or (Distance(vc) ≠ d);
if Active(vc) = true then Enqueue(vc, Q);
c ← c + 1;
if c > NUMNODE then begin
c ← 0;
GlobalRelabel;
end;
end;
end
procedure Mincut;
var
vc : NodeCoord; c : integer;
begin
Maxflow;
FindCut;
end
RAMIFICATIONS AND SCOPE
[0132] While only certain preferred features of the invention have been illustrated and described herein, many modifications and changes will occur to those skilled in the art.
[0133] For instance, weight for an edge between neighboring voxel nodes can be set according to the difference of the data value between the two voxels so that it becomes greater if the values are closer to each other, making it less likely for the voxels to be divided in different partitions.
[0134] As mentioned above, the method of present invention can use either directed or undirected graph. According to the application and the specific implementation of the data structures, either can be more convenient than the other.
[0135] Also, there are known ways to handle specific cases more efficiently. First, if there is any edge with a zero weight in the graph, the edge can be removed without affecting the result of the segmentation. Second, if there is a pair of nodes that are very strongly connected, that is, if the nodes are connected by either (a) edges with very large weights in both directions in the directed case, or (b) by an undirected edge with a very large weight in the undirected case, these nodes will never be separated in the minimum-cut algorithm. Thus, it is possible to merge these two nodes into one node to improve the efficiency. These are well known in the art as pre-processes of minimum-cut algorithms. In such a case, there may be fewer voxel nodes than input voxels. This can be seen as corresponding voxel nodes being designated to each input voxel. In the embodiment above, the designation is a simple one to one correspondence. It can be, however, such that more than one voxel have the same designated voxel node. This simply means two voxels that has the same designated corresponding voxel node cannot be separated. After the minimum cut is found, i.e., the nodes are partitioned into groups, the segmentation of the voxels can be readily found by assigning each voxel to the segment corresponding to the group to which the voxel's corresponding voxel node belongs.
[0136] FIG. 7A shows the simplest example to illustrate this. There are three voxels, u, v, and w. Each voxel is neighbor of other two. Suppose the voxels u and w are known to have so strong a tendency to stay in the same segment that it can be assume they never can be separated. The undirected version of the method of present invention would usually give the graph shown in FIG. 7B . However, it is known that the graph shown in FIG. 7C would give an equivalent solution with fewer nodes and edges. Here, the nodes u and w are merged to one node 71 . The edges connecting s, t, or v and u and w are also merged and their weights added together. Thus, instead of edges (s,u) and (s,w) in FIG. 7B , there is only one edge from s to node 71 in FIG. 7C with a weight equal to the sum of weights of the original edges. In this example, node 71 is designated as the voxel node corresponding to both u and w. Node 72 is, on the other hand, designated as the voxel node corresponding to only one voxel, which is v, as in the ordinary case. By repeating this, it is possible to merge more than one node. The weight of an edge connecting some node x and a merged node y is given by the sum of weights of all edges that connect node x and all nodes that are merged into y. In the context of the present invention, this means that the equation (2) becomes, for a voxel node v,
[0000]
w
(
s
,
v
)
-
w
(
v
,
t
)
=
∑
all
x
corresponding
to
v
a
(
x
)
.
[0137] Note if, as in the embodiment above, each voxel node corresponds to exactly one voxel, this equation reverts to (2). This is nothing but an obvious result of applying the merging to the present context. This process of merging is well known in the art and its addition should not be considered to bring the resultant method out of the scope of the present invention.
[0138] Finally, as mentioned above, there are known more than one minimum-cut algorithms. Also, there are approximation algorithms that give approximate minimum cut. Moreover, some approximation algorithms can give so-called multiway-cut that partitions the graph into more than two groups. Such algorithms however can be easily incorporated into the scheme of the present invention by those skilled in the art.
[0139] It is, therefore, to be understood that the appended claims are intended to cover all such modifications and changes as fall within the true spirit of the invention. | A method is disclosed to automatically segment 3D and higher-dimensional images into two subsets without user intervention, with no topological restriction on the solution, and in such a way that the solution is an optimal in a precisely defined optimization criterion, including an exactly defined degree of smoothness. A minimum-cut algorithm is used on a graph devised so that the optimization criterion translates into the minimization of the graph cut. The minimum cut thus found is interpreted as the segmentation with desired property | 6 |
PRIORITY CLAIM
This application is a continuation of U.S. patent application Ser. No. 12/857,622 entitled “DOWNLINK AND UPLINK ARRAY AND BEAMFORMING ARRANGEMENT FOR WIRELESS COMMUNICATION NETWORKS” to Smith et al., filed Aug. 17, 2010, which is a continuation of U.S. patent application Ser. No. 10/358,914 entitled “DOWNLINK AND UPLINK ARRAY AND BEAMFORMING ARRANGEMENT FOR WIRELESS COMMUNICATION NETWORKS” to Smith et al., filed Feb. 5, 2003, now U.S. Pat. No. 7,792,547, all of which are incorporated herein by reference in their entirety.
FIELD OF THE INVENTION
This invention relates to an antenna array and beamforming arrangement for a base station in a wireless communications network. It is particularly applicable, but in no way limited, for use in a cellular communications network, for transmitting and receiving signals to and from mobile stations such as mobile phones or personal data assistants.
BACKGROUND
The term “wireless communications network” is used herein to refer to a communications network comprising at least one base station transceiver arranged to communicate with at least one mobile station. It will be appreciated by those skilled in the art that a wireless communications network will often take the form of a cellular communications network, in which a plurality of base station transceivers each define a geographical cell. Mobile stations located in the communications network communicate with one or more base station transceivers, for example, the closest one to the mobile station. Each base station transceiver has a limited range and a cell can be considered to be a geographical region over which a base station transceiver can communicate effectively with a mobile station therein.
Mobile stations such as mobile telephones may be located within a cellular communications network to send and receive signals to and from the base station transceivers. Each mobile station operating within a cell requires a certain amount of bandwidth to operate and because the total bandwidth of base station transceivers is limited the number of mobile stations which can operate within a cell is limited.
The provision of base stations is expensive. Firstly, the location and surveying of suitable sites for base stations is time consuming and complex since the location of any one base station impacts the base station requirements for adjacent cells. Furthermore, obtaining planning or zoning permission for base stations is becoming increasingly difficult as a result not least of concerns about electromagnetic emissions and the aesthetic impact of antenna towers.
Accordingly, there is a general desire to minimise the number of base stations. This may be achieved by improving the coverage of base stations i.e. the geographical area over which sufficient radiated powers are produced to allow effective communication with mobile stations and/or increases in capacity i.e. the number of mobile stations which may be supported by a single base station. Assuming that these aims may be met without a disproportionate increase in base station costs, it is generally understood that a reduction in the number of base stations is desirable.
One traditional approach to this problem has been to increase “sectorisation” at the base, i.e. to use a single base station location to provide coverage in different “sectors” which are arranged radially around the base station location.
Many existing systems use “tri-sectoring” in which three sectors are covered using a single base station. The prior art tri-sectoring arrangement increases both uplink and downlink capacity by a factor of almost three compared to a basic omni-directional arrangement. However, the improvement is less than three times since perfect sectorisation is not possible i.e. there is always some overlap between adjacent sectors. This loss is called partition loss and typically increases with the number of sectors at the base. Using multibeam technology to replace each sector with an array, allows beams to be formed which are narrower than the full sector width. This has a similar effect to increased sectorisation and thus improves capacity. These arrays may for example comprise a plurality of columns of antenna elements which may or may not be combined using a beam former to produce a lesser or equal number of beams by combining the outputs of the columns, for example using a Butler matrix. For N columns there can be up to (and including) N orthogonal beams.
Typically each such sector uses an antenna having a plurality of elements which provide a plurality of beams. Typically three fixed beams are used both for uplink and downlink connections in each sector. Thus in the prior art, an antenna may be used to provide three sector coverage with three beams in each of these sectors. Using an array for each sector, narrower beams may be used which may be directed when the antenna is configured, to different parts of the sector. Since the beams typically overlap, additional information is available on the uplink which may be used using conventional space-time signal processing techniques, to provide additional spatial processing gain in the uplink.
These steps have gone some way towards providing increased capacity in base stations. Nevertheless, it is anticipated that capacity requirements will increase three or four fold from present day levels within a short space of time. This capacity requirement cannot be met with a three or four fold increase in the number of base station sites for at least the reasons explained above. Thus yet further improvements to base station capacities are required.
U.S. Pat. No. 6,480,524 describes a six column array for the downlink using a three way beam former which gives good capacity benefits. Whilst it would be possible to produce three beams from a three column array, the use of a six column array allows more control of the beam shape. By shaping the beams with “deep cusps” (by using multiple elements for each beam) overlap between the beams is reduced which in turn reduces “partition loss”. This partition loss is characterised in part by interference between adjacent beams directed to different mobile stations within a sector and also by increased hand-off overhead as mobile stations hand-off back and forth between overlapped beams. Thus in the case of the downlink, there are significant advantages in reducing overlap, as explained in U.S. Pat. No. 6,480,524.
In terms of apparatus size, for the downlink it would be possible to use a six column array at the top of the mast, and maximum downlink capacity would be achieved by forming six beams with this array. However, each downlink beam would require an expensive power amplifier, together with cabling up the mast. As mentioned above, using fewer beams than columns also provides improved beam shapes. Thus, a good cost/capacity tradeoff for the downlink is a 6 column array with 3 deep cusp beams.
A further consideration in base station design is the possibility of using the same antenna array both for the uplink and downlink. The use of separate arrays requires larger areas of land and also generally has increased aesthetic impact. Where the arrays are mounted on the same structure, additional arrays also produce increased wind loading problems. Thus it is generally desirable to attempt to use the same array i.e. a common array, both for the uplink and downlink communications. However, this may place compromises on the design of the uplink antenna which typically is configured (i.e. constructed and fed) identically to that of the downlink.
Thus in practice, the capacity of a state-of-the-art base station is asymmetric i.e. greater downlink capacity is available than uplink capacity. Whilst this may be suitable for some data applications such as web-browsing or streaming video, it is unsuitable for applications such as voice communications.
SUMMARY
According to a first aspect of the invention there is provided an antenna array suitable for use in a base station in a wireless communications network, the antenna array having a first beamforming arrangement for producing uplink beams and a second beamforming arrangement for producing downlink beams, wherein the first and second beamforming arrangements are different from one another. The use of two beamforming arrangements provides the advantage that the number and shape of beams on the uplink and downlink can be independently designed to suit their differing requirements, resulting from different cost/capacity tradeoffs.
This array takes advantage of the different technical considerations for the uplink as compared to the downlink. Thus for example in the six column array described in U.S. Pat. No. 6,480,524, all six columns may be used as separate uplink receiver branches. In general, a large number of separate antenna elements for the uplink is desirable since this improves the space combiner gain and this being the case, beam overlap problems are less significant than in the downlink. Furthermore, the cost implications of multiple antenna elements is different. Power amplifiers for the downlink are considerably more expensive than low noise amplifiers required for the uplink and thus as explained in more detail below, the cost and cabling trade-offs for the uplink are different to those for the downlink. It has been found that the increased costs of using a separate beam forming arrangement for the uplink are more than outweighed by the improvements in uplink capacity for the base station.
Preferably the first and second beamforming arrangements feed a common antenna array to produce the uplink and downlink beams. A common array is an array which is used for both transmitting and receiving signals. Using a common antenna array provides the advantage that separate antenna arrays for the uplink and downlink are not required.
Preferably a plurality of (sin x/x) beams are formed for the uplink, and a plurality of low cusp beams are formed for the downlink. Preferably these beams are dual polar, and thus the antenna may advantageously be arranged to achieve diversity gain from the dual polar beams in both the downlink (transmit diversity) and uplink (receive diversity) directions.
In a preferred embodiment, the antenna array is arranged such that three dual polar low cusp beams are formed for the downlink, and six dual polar (sin x/x) beams are formed for the uplink.
The antenna array may have a six column arrangement in which the six antenna column outputs are fed directly to the receiver equipment for combination, rather than being combined at the masthead in a beamformer to give beams.
The number of uplink beams produced by the first beamforming arrangement may be twice as many as the number of downlink beams produced by the second beamforming arrangement. This enables the uplink capacity to be enhanced by a factor of approximately 2 times, without impacting the downlink performance, whilst still using a common array.
In one preferred embodiment, the number of uplink beams is four and the number of downlink beams is two. In another preferred embodiment, the number of uplink beams is six and the number of downlink beams is three.
The second beamforming arrangement may be configured to transmit multiple input multiple output (MIMO) transmissions. The first beamforming arrangement may also in principle be configured to receive MIMO transmissions.
Preferably the antenna array comprises a three beam downlink, a six beam uplink, and a plurality of circulators. Alternatively the antenna array may comprise a three beam downlink, a six beam uplink, and a plurality of filters to separate the uplink and downlink signals, the filters being arranged to discriminate on the basis of frequency. A second alternative for time domain duplexed systems (as currently deployed for Wireless LAN or UMTS in time domain duplex mode) would use multiple switches to separate the uplink and downlink signals
The uplink arrangement may use maximal ratio combining or minimum mean squared error combining.
A separate pilot may be used on each of the downlink beams. On the uplink, individual pilot signals are typically transmitted by each mobile station.
According to a second aspect of the invention there is provided a masthead of a base station transceiver including an antenna array having a first beamforming arrangement for producing uplink beams and a second beamforming arrangement for producing downlink beams, wherein the first and second beamforming arrangements are different from one another.
According to a third aspect of the invention there is provided a cellular communications network including an antenna array having a first beamforming arrangement for producing uplink beams and a second beamforming arrangement for producing downlink beams, wherein the first and second beamforming arrangements are different from one another.
According to a fourth aspect of the invention there is provided a cellular communications network comprising a plurality of cells, wherein a plurality of said cells each contains a base station transceiver having a first beamforming arrangement for producing uplink beams and a second beamforming arrangement for producing downlink beams, wherein the first and second beamforming arrangements are different from one another.
For each base station transceiver, preferably the first and second beamforming arrangements feed a common antenna array to produce the uplink and downlink beams.
Preferably a plurality of (sin x/x) beams are formed for the uplink, and a plurality of low cusp beams are formed for the downlink. Preferably these beams are dual polar.
Particularly preferably each antenna array is arranged such that three dual polar low cusp beams are formed for the downlink, and six dual polar (sin x/x) beams are formed for the uplink.
According to a fifth aspect of the invention there is provided a base station transceiver for use in a wireless communications network, the base station transceiver having an antenna array, the antenna array having a first beamforming arrangement for producing uplink beams and a second beamforming arrangement for producing downlink beams, wherein the first and second beamforming arrangements are different from one another.
Preferably the first and second beamforming arrangements feed a common antenna array to produce the uplink and downlink beams.
Preferably a plurality of (sin x/x) beams are formed for the uplink, and a plurality of low cusp beams are formed for the downlink. Preferably these beams are dual polar.
Particularly preferably the antenna array is arranged such that three dual polar low cusp beams are formed for the downlink, and six dual polar (sin x/x) beams are formed for the uplink.
According to a sixth aspect of the invention there is provided a radio signal received on a plurality of (sin x/x) beams forming an uplink of a cellular communications network.
According to a seventh aspect of the invention there is provided an antenna array suitable for use in a base station in a wireless communications network, the antenna array having a plurality of antenna elements of which at least some are combined to form a beam for transmitting downlink signals and at least some are used to form a beam for receiving uplink signals, wherein the uplink and downlink beamforming arrangements are different from one another.
According to an eighth aspect of the invention there is provided a method of operating a wireless communications network, comprising using an antenna array having a first beamforming arrangement to produce uplink beams and a second beamforming arrangement to produce downlink beams, wherein the first and second beamforming arrangements are different from one another.
Preferably the method further comprises using a common antenna array to produce the uplink and downlink beams.
Preferably the method further comprises forming a plurality of (sin x/x) beams for the uplink, and a plurality of low cusp beams for the downlink.
In a preferred embodiment the method further comprises forming three dual polar low cusp beams for the downlink, and six dual polar (sin x/x) beams for the uplink.
Preferably the method comprises combining at least some of the antenna elements to form a beam for transmitting downlink signals and using at least some of the antenna elements to form a beam for receiving uplink signals, wherein the uplink and downlink beamforming arrangements are different from one another.
Preferably the wireless communications network is a cellular wireless communications network.
Other aspects and features of the present invention will become apparent to those ordinarily skilled in the art upon review of the following description of specific embodiments of the invention in conjunction with the accompanying figures.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates uplink array processing options, associated implementation architecture, and antenna patterns as used in the simulations.
FIG. 2 illustrates a 3-beam downlink/3-beam uplink architecture.
FIG. 3 illustrates a 3-beam downlink/6-column uplink architecture.
FIG. 4 illustrates a 3-beam downlink/6-beam uplink architecture.
FIG. 5 is a plot of simulated CDMA coverage loss vs. capacity for different uplink architectures.
FIG. 6 shows filter specifications suitable for a 6-column/6-beam uplink with masthead LNA's.
FIG. 7 illustrates comparisons between a full sector antenna, a three low cusp beam arrangement, and a six column arrangement.
FIG. 8 illustrates an example of a suitable six column masthead antenna arrangement.
DETAILED DESCRIPTION
The problem of how to enhance the uplink capacity of a base station, without the need to use separate antenna arrays for the uplink and downlink, has been addressed by developing an antenna array having a first beamforming arrangement for the uplink in which preferably a plurality of (sin x/x) beams are formed, and a second beamforming arrangement for the downlink in which preferably a plurality of low cusp beams are formed. The two beamforming arrangements use a common antenna array. This approach is described in detail below.
A key issue is to determine whether an uplink architecture to support the 6-column combining (or 6-beam) options is viable, due to the increased complexity. This has not been considered before and goes against accepted practice. It has been concluded, as explained below, that such an architecture can be implemented for the uplink, and that it is possible for the uplink and downlink architectures to differ.
The analysis and simulation results which follow indicate better performance for a 6-beam uplink than for a 6-column combining scheme, although in principle the best possible performance should be similar as it is possible for the 6-column combination to apply the same transform as the 6×6 beamformer, thereby generating the (sin x/x) beams digitally. The preferred solution in terms of uplink capacity is therefore to include a 6×6 uplink beamformer at the masthead, either with or without an active masthead, depending on the coverage requirements.
As a way of increasing the uplink sensitivity, architectures in which all six of the antenna array columns are combined coherently appear feasible. This does increase the total cost of the cell-site but becomes a viable option if the additional array processing also provides an increase in capacity, such that the total cost per area for a network deployment is reduced. This can be achieved either by combining all 12 antenna columns within a sector (i.e. six array columns from 2 polarisations) using digital Maximal Ratio Combination (MRC) or minimum mean squared error (MMSE) combining in the Node B cabinet, or alternatively by forming six fixed polarisation diverse beams within each sector. In both of these approaches, there are consequently 36 cables per cell-site, as opposed to 18 cables if the uplink antenna configuration was identical to the downlink. This raises issues relating to the weights of feeder cables and the weights of any masthead electronics. For such an uplink architecture, the total weight per channel should be minimised, such that the increased gain due to array processing is not negated by the need to use very low weight (and high loss) feeder cables.
In considering the use of array processing to enhance the uplink, it is important to understand the capacity and link budget implications of the different beamforming and maximal ratio combining (MRC) options. Simulations have been conducted for asynchronous code divisional multiple access (A-CDMA) and synchronous code divisional multiple access (S-CDMA) networks, modelling the capacity available for systems with either a 3-beam uplink, 6-column MRC, or a 6-beam uplink. Our results for A-CDMA networks predict an extra 2× capacity increase for either 6-column MRC or 6 sin x/x beams, relative to a system with 3 deep-cusp beams. (These configurations therefore give 6× capacity gain relative to baseline tri-cellular.) The antenna patterns as used in the simulations, and associated implementation architecture, are shown schematically in FIG. 1 .
Similarly, it can be argued that there is an additional link budget gain available using 6-column MRC, or 6×6 beamformer, relative to the 3-beam architecture. We suggest a 6.8 dB array processing gain for 6-column MRC relative to 3.8 dB for the 3-beam architecture (assuming that the 3 beams are also MRC combined, providing additional gain for the user equipment (UE) at azimuths which fall in the deep cusps of the beam pattern). There is then a 3 dB gain for the 6-column or the 6-beam architecture relative to the 3-beam architecture.
Then it is important to demonstrate that the capacity benefits and the link budget benefits are available in combination, as opposed to providing either a capacity or a link budget gain. This has been approached via consideration of CDMA capacity equations as an aid to interpreting the results of the capacity simulations. These capacity equations have also been used to compare the network capacities of different options, but the aim of this is to interpret the simulations which use representative path loss models and beam patterns and so are ultimately more accurate than the simple capacity predictions. It should be noted however that the simulations do not include a representation of a maximum UE transmit power.
The following discussion presents a more detailed review of four viable architecture options, these being:
3 beam, no active masthead electronics
3 beam, with masthead LNA's and filters
6 column combining, no active masthead electronics
6 column combining, with masthead LNA's and filters
These are illustrated in FIGS. 2 and 3 , with FIG. 4 showing the 6 beam variants.
This capacity and link budget analysis takes a basic CDMA capacity equation and extends it to include the additional array processing factors. The network capacity is compared for a common ‘operating point’ which corresponds to a common proportion of the system ‘pole capacity’ where this ‘pole’ is reached asymptotically as the system becomes interference limited (i.e. interference to noise ratio tends to infinity) and the number of users in the system reaches a maximum.
The A-CDMA capacity results are compared for a common ‘noise rise’, i.e. the rise in noise plus user signal power, as measured at a single antenna column output. In this case, the interference consists of the combined power from each of the users within the sector or beam. In terms of a link budget for a particular user, the noise rise metric includes the power of this ‘wanted’ user.
For an S-CDMA system, the capacity is not only dependent on the noise rise, representing the amount of power from other users, but also on the degree to which this power is orthogonal to the wanted user (due to the use of orthogonal CDMA codes and also to dispersion). A ‘coverage loss’ metric is proposed, being a measure of the increase in power for each user at the receiver, required in order to overcome noise and interference from other users. This depends on both the number of other users and the extent to which their power is orthogonal. For the capacity predictions included here, capacity figures are compared on the basis of a 3 dB coverage loss, i.e. for a network in which the received power from a wanted user is 3 dB higher than it would be if it were the only user in the network.
The capacity for an A-CDMA network is defined as follows, relative to the signal to noise plus interference ratio required at the received for a user:
R = ( E b I 0 + N 0 ) · ( r b B )
where:
R is the signal to noise plus interference ratio required per user (following beam and MRC gain); r b is the information rate; and B is the CDMA chip rate (assumed to be the receiver bandwidth).
The link budget impact can be defined by the comparing the required power per user relative to thermal noise:
P k N = L R b m
where:
P k is the received power from each user in the sector; N is the thermal noise level at the receiver; b is the number of beams per sector; m is the number of channels per beam combined in MRC; and L is the coverage loss relative to a user in noise only (i.e. no interference from other users).
So, for the case with a 3-beam polarisation diversity uplink, m=2 and b=3. Similarly for the 6-column polarisation diversity uplink, m=12 and b=1. For the 6-beam polarisation diversity uplink, m=2 and b=6. This makes a simple assumption that, if a sector is divided into beams, there is a flat-topped beam pattern with gain (relative to the sector-wide pattern) equal to the number of beams. Interference from adjacent sectors or beams is assumed to be included together with the other-cell interference.
The number of users per sector is then:
k A = b [ m ( L - 1 ) + L R ] [ L R ( 1 + α ) ]
where:
k A is the number of users per A-CDMA sector; and a is the relative power of other-cell interference relative to intra-cell interference (see below).
For an S-CDMA network, the link budget impact is specified as above. The capacity equation assumes that there are a number of non-interfering users within the cell that use the same outer spreading code but different Walsh codes. If the number of users per sector is greater than the number of Walsh codes, these users will be assigned a different outer spreading code and so will cause interference to the wanted user. There is therefore a breakpoint in the capacity equation when the number of users per sector equals the number of available Walsh codes multiplied by the number of beams. This number of available Walsh codes is equal to the processing gain (B/r b ) for data links in which a single Walsh code is used per UE uplink.
The capacity is then given by:
For
L
<
L
B
k
S
=
b
[
m
(
L
-
1
)
+
L
R
β
]
[
L
R
(
β
+
α
)
]
For
L
≥
L
B
k
S
=
b
[
m
(
L
-
1
)
+
L
R
(
β
+
s
-
β
s
)
]
[
L
R
(
1
+
α
)
]
And breakpoint L B , corresponding to the case when k=s*b
L B = m [ m - R ( β ( s - 1 ) + α s ) ]
where:
k s is the number of users per S-CDMA sector; β is the orthogonality factor; and s is the number of Walsh codes available.
Taking the S-CDMA case with s=1, it can be verified that the S-CDMA capacity equation reduces to become the A-CDMA case. This also occurs if orthogonality is lost due to dispersion, i.e. if β=1.
In order to represent other-cell interference, the factor α included above has been defined by calibrating these capacity estimates against simulation results for the single-sector case with MSNIR combination. The resulting other-cell interference ratio (α=0.45) has then been used in predicting capacity values for other configurations and/or the S-CDMA cases. This parameter corresponds to a ‘geometry factor’ of 0.65. For the 6-beam architecture, the increased beam sidelobes has been represented by a value of α=0.63.
For S-CDMA, the orthogonality factor has been assumed to be β=0.5. This implies that, for users with nominally orthogonal Walsh codes, a factor of 0.5× the received power is also included as interference the wanted user.
Capacity and link budget results are presented here for E b /(N 0 +I 0 )=2 dB. This represents a 960 kbps data link with a processing gain of 6 dB where B=3.84 Mcps, and provides up to 4 Walsh codes available for use with a common outer spreading code. The variation of capacity with coverage loss for both asynchronous and synchronous systems is shown in FIG. 5 .
FIG. 5 shows that, for a nominal coverage loss of 3 dB, 6-beam S-CDMA enables the greatest number of users per sector (i.e. the greatest capacity). The next greatest capacity is obtained using 6-beam A-CDMA, followed (in order of decreasing capacity) by 6-column S-CDMA, 6-column A-CDMA, 3-beam S-CDMA, 3-beam A-CDMA, full sector S-CDMA and finally full sector A-CDMA.
The link budget and capacity benefits can be summarised for a 3 dB coverage loss as follows:
Link
A-CDMA
S-CDMA
Option
budget
capacity
capacity
3-beam,
0 dB
7.3 users/sector
×1
9.5 users/sector
×1.3
dual-polar
(ref)
(ref)
6-column,
+3 dB
11.1 users/sector
×1.5
12.2 users/sector
×1.7
dual-polar
6-beam,
+3 dB
13.0 users/sector
×1.8
16.0 users/sector
×2.2
dual-polar
This suggests that the 6-column dual-polar uplink provides a significant capacity increase over a 3-beam architecture. The 6-beam approach uses an alternative combination of the array columns and, from this analysis, gives a higher capacity. Simplistically, the 6-beam scheme would provide 2× capacity relative to a 3-beam scheme, but some of this additional gain is lost due to the higher sidelobes of the sin x/x beams as opposed to the deep cusps in the 3-beam pattern. The 6-column scheme provides a lower capacity gain than the 6-beam scheme as users see interference from all of the users within a sector, rather than just those within the same beam. For S-CDMA, the 6-column scheme gains less from the use of orthogonal codes, relative to the beamforming schemes, as the capacity equations above assume that the Walsh code set can be used only once per sector, as opposed to once per beam.
The results above can be compared with A-CDMA simulation results. For a 3 dB noise rise, these results would be as follows:
A-CDMA capacity for 3 dB noise
Normalised
Option
rise (max SNIR combining)
capacity gain
3-beam,
6.0 users/sector
×1.0 (ref.)
dual-polar
6-column,
11.7 users/sector
×1.9
dual-polar
6-beam,
12.1 users/sector
×2.0
dual-polar
These results are based on full system simulation using appropriate beam patterns and representative distributions of UE's within a network layout. In terms of capacity, the simulations can be considered to be more accurate than the results of the analysis presented here, but the analysis indicates that there is also a link budget gain available and that this is provided together with the capacity benefit.
Further comparisons between a full sector antenna, a three low cusp beam arrangement, and a six column arrangement are illustrated in FIG. 7 .
As described above, the capacity and link budget benefits of a 6-column MRC or 6-beam uplink were summarised. Cost is also a key concern for the future system architectures. Techniques which allow the network cost to be minimised are therefore of great interest. This may be achieved through reducing the cost of each Node B site, but also by providing increased range, such that the overall number of Node B installations is reduced. Solutions providing a greater capacity or coverage per sector are therefore likely to be more cost effective.
Masthead weight is one of the key constraints. It has been assumed here that the total masthead weight (including feeder cables, masthead electronics and any additional antenna weight) cannot be increased beyond the weight of an existing tri-sector receive-diversity cell-site. This allows for the weight of 6 cables which are assumed to be up to 1⅝″ diameter. The Andrew Corporation Heliax LDF series cable products have been used here as a reference, following a comparison with other cable vendors which showed these to be typical of cable insertion loss vs. weight characteristics.
Potentially, a greater weight could be allowed for a future system architecture if it were to replace multiple legacy systems. The aspect is not considered in detail here as it implies multiplexing between operators or frequency bands and therefore would involve additional hardware. However, the use of shared infrastructure or multi-band diplexers offers significant potential for reducing the overall weight of the tower installation.
Typical cell-site tower installations are rated to carry a maximum of 12⅝″ diameter cables. This is consistent with the supported antenna installation of tri-sector GSM and dual-band DCS1800/UMTS each with receive diversity. This provides an indication of the upper bound to the total weight that may be permitted for a future system architecture supporting multiplexed legacy systems.
Comparing costs for a dense urban high-base environment, assuming 30 m feeder cables, there is a lower network cost for installations using the 6-beam (or 6-column) uplink scheme. There is a potential 38% improvement in cost of Node B's per uplink capacity provided. In terms of coverage, the lowest cost per unit area is given using the 6-beam uplink combined with masthead LNA's. If masthead LNA's are not included, the cost per unit area is not significantly improved over the 3-beam uplink (although there is still a capacity doubling) as the link budget benefits of the additional interference and noise reduction are negated by the higher masthead cost. It should also be noted that the masthead weight for the 6-beam uplink does not increase relative to the 3-beam design, and current estimates actually show a useful reduction. The costs here exclude the site and backhaul costs which would also tend to de-weight the increase in masthead cost over a larger coverage area.
Results for dense urban low base (20 m feeder cables) and suburban path loss model (40 m cables) are very similar. In the suburban case, the 3-beam architecture including masthead amplifiers provides the best cost per unit area ratio. The 6-beam uplink including masthead amplifiers has almost as good a cost per unit area ratio, but with the additional benefit of the capacity doubling
Thus, the proposed preferred beamformer design uses a 6×6 Butler matrix followed by combiners to pair up beam ports such that three dual polar low cusp beams are formed for the downlink, and six (sin x/x) beams (also dual polar) are formed for the uplink. The appropriate rf circuitry (e.g. circulators, filters etc.—as shown, for example, in FIG. 4 ) are incorporated in a common array. Circulator devices typically offer a 20 dB isolation with minimal cost or weight compared to filter structures. This isolation assists in reducing filter requirements without the need for physical separation of the antenna elements. Circulators are a device which allows the downlink and uplink signals to be discriminated (based on the signal direction of propagation), such that they follow different paths at the masthead (e.g. downlink through a 3×6 beamformer and uplink through the LNA). It should be noted that circulators provide one implementation method, but any means of separating the uplink and downlink signals would be applicable. One alternative is to use filters (particularly diplexer filters) in which the discrimination is based on the use of different frequency bands for uplink and downlink signals. However, our proposed design uses circulators as one possible means of implementation without excessive weight, based on a prediction of future component capabilities.
This is an optimum arrangement for the downlink in terms of efficient use of PA's and cost per unit of capacity (as discussed in U.S. Pat. No. 6,480,524). Using six (sin x/x) beams for the downlink would be sub-optimal due to beam overlap. However, this does not impact the uplink similarly, and six (sin x/x) beams offer approximately twice the capacity of three low cusp beams for the uplink.
An efficient arrangement using circulators at the masthead has been found which allows three beam downlink and six beam uplink (for both polarisations), as shown in FIG. 4 . A six column arrangement is shown in FIG. 3 . More cables are required, but these may be of reduced diameter such that the total weight, wind loading and cost are maintained, and the uplink link budget is also enhanced due to the extra combining gain provided.
Filter specifications suitable for the 6-column/6-beam uplink with masthead LNA's are shown in FIG. 6 .
An example of a suitable six column masthead antenna arrangement is illustrated in FIG. 8 . This arrangement uses +45°/−45° dual polarisation over six columns to generate 12 beams. Each X-shaped component comprises a +45° element and a −45° element. Using dual polarisation, the problems caused by Doppler effects and the effects of buildings, which give rise to fading or cancellation (as a result of signal recombination) or multipath effects, can be mitigated. The use of dual polarisation allows diversity gain to be achieved.
Further improvement may be achieved using MMSE combining rather than the MRC described above. MMSE combining provides benefit in particular when the interference distribution is spatially ‘coloured’ (i.e. correlated from antenna column to antenna column, or from beam to beam). If the interference were spatially ‘white’ (i.e. uncorrelated from antenna column to antenna column, or from beam to beam) then the MMSE combining solution would be identical to the MRC combining solution. Simulations indicate that MMSE combining typically adds some 10-25% to the uplink capacity.
In another alternative embodiment the antenna array may be arranged such that two dual polar low cusp beams are formed for the downlink, and four dual polar (sin x/x) beams are formed for the uplink, or indeed any multiples of uplink and downlink beams may be chosen according to application requirements.
While the invention has been described according to what is presently considered to be the most practical and preferred embodiments, it must be understood that the invention is not limited to the disclosed embodiments. Those ordinarily skilled in the art will understand that various modifications and equivalent structures and functions may be made without departing from the spirit and scope of the invention as defined in the claims. Therefore, the invention as defined in the claims must be accorded the broadest possible interpretation so as to encompass all such modifications and equivalent structures and functions. In particular, it will be understood that the numbers of antenna elements, beams and beam patterns may vary according to application.
LIST OF ABBREVIATIONS
CDMA Code Division Multiple Access
A-CDMA Asynchronous Code Division Multiple Access
S-CDMA Synchronous Code Division Multiple Access
CEM Common Element Manager
DPCCH Dedicated Physical Control Channel
DPDCH Dedicated Physical Data Channel
LNA Low Noise Amplifier
MIMO Multiple Input Multiple Output
MMSE Minimum Mean Squared Error
MRC Maximal Ratio Combining
MSNIR Maximal Signal to Noise plus Interference Ratio
PA Power Amplifier
UE User Equipment
List of Abbreviations
CDMA
Code Division Multiple Access
A-CDMA
Asynchronous Code Division Multiple Access
S-CDMA
Synchronous Code Division Multiple Access
CEM
Common Element Manager
DPCCH
Dedicated Physical Control Channel
DPDCH
Dedicated Physical Data Channel
LNA
Low Noise Amplifier
MIMO
Multiple Input Multiple Output
MMSE
Minimum Mean Squared Error
MRC
Maximal Ratio Combining
MSNIR
Maximal Signal to Noise plus Interference Ratio
PA
Power Amplifier
UE
User Equipment | System and methods of cellular communications network are described herein. In one system, an antenna array is described. The antenna array has a first beamforming arrangement for producing uplink beams and a second beamforming arrangement for producing downlink beams. The first and second beamforming arrangements are different from one another. The wireless communication network communicates with a mobile station by use of the uplink and downlink beamforming arrangements. | 7 |
BACKGROUND
[0001] I. Field of the Invention
[0002] The present invention relates to communication systems, more particularly, to local authentication of a communication system subscriber.
[0003] II. Background
[0004] The field of wireless communications has many applications including, e.g., cordless telephones, paging, wireless local loops, personal digital assistants (PDAs), Internet telephony, and satellite communication systems. A particularly important application is cellular telephone systems for mobile subscribers. (As used herein, the term “cellular” systems encompasses both cellular and personal communications services (PCS) frequencies.) Various over-the-air interfaces have been developed for such cellular telephone systems including, e.g., frequency division multiple access (FDMA), time division multiple access (TDMA), and code division multiple access (CDMA). In connection therewith, various domestic and international standards have been established including, e.g., Advanced Mobile Phone Service (AMPS), Global System for Mobile (GSM), and Interim Standard 95 (IS-95). In particular, IS-95 and its derivatives, IS-95A, IS-95B, ANSI J-STD-008 (often referred to collectively herein as IS-95), and proposed high-data-rate systems for data, etc. are promulgated by the Telecommunication Industry Association (TIA) and other well known standards bodies.
[0005] Cellular telephone systems configured in accordance with the use of the IS-95 standard employ CDMA signal processing techniques to provide highly efficient and robust cellular telephone service. Exemplary cellular telephone systems configured substantially in accordance with the use of the IS-95 standard are described in U.S. Pat. Nos. 5,103,459 and 4,901,307, which are assigned to the assignee of the present invention and fully incorporated herein by reference. An exemplary described system utilizing CDMA techniques is the cdma2000 ITU-R Radio Transmission Technology (RTT) Candidate Submission (referred to herein as cdma2000), issued by the TIA. The standard for cdma2000 is given in draft versions of IS-2000 and has been approved by the TIA. The cdma2000 proposal is compatible with IS-95 systems in many ways. Another CDMA standard is the W-CDMA standard, as embodied in 3 rd Generation Partnership Project “ 3 GPP ”, Document Nos. 3G TS 25.211, 3G TS 25.212, 3G TS 25.213, and 3G TS 25.214.
[0006] Given the ubiquitous proliferation of telecommunications services in most parts of the world and the increased mobility of the general populace, it is desirable to provide communication services to a subscriber while he or she is travelling outside the range of the subscriber's home system. One method of satisfying this need is the use of an identification token, such as the Subscriber Identity Module (SIM) in GSM systems, wherein a subscriber is assigned a SIM card that can be inserted into a GSM phone. The SIM card carries information that is used to identify the billing information of the party inserting the SIM card into a mobile phone. Next generation SIM cards have been renamed as USIM (UTMS SIM) cards. In a CDMA system, the identification token is referred to as a Removable User Interface Module (R-UIM) and accomplishes the same purpose. Use of such an identification token allows a subscriber to travel without his or her personal mobile phone, which may be configured to operated on frequencies that are not used in the visited environment, and to use a locally available mobile phone without incurring costs in establishing a new account.
[0007] Although convenient, the use of such identification tokens to access account information of a subscriber can be insecure. Currently, such identification tokens are programmed to transmit private information, such as a cryptographic key used for message encryption or an authentication key for identifying the subscriber, to the mobile phone. A person contemplating the theft of account information can accomplish his or her goal by programming a mobile phone to retain private information after the identification token has been removed, or to transmit the private information to another storage unit during the legitimate use of the mobile phone. Mobile phones that have been tampered in this manner will hereafter be referred to as “rogue shells.” Hence, there is a current need to preserve the security of the private information stored on an identification token while still facilitating the use of said private information to access communication services.
SUMMARY
[0008] A novel method and apparatus for providing secure authentication to a subscriber roaming outside his or her home system is presented. In one aspect, a subscriber identification token is configured to provide authentication support to a mobile unit, wherein the mobile unit conveys information to the subscriber identification token for transformation via a secret key.
[0009] In another aspect, a subscriber identification module for providing local authentication of a subscriber in a communication system is presented, comprising: a memory; and a processor configured to implement a set of instructions stored in the memory, the set of instructions for: generating a plurality of keys in response to a received challenge; generating an authentication signal based on a received signal and a first key from the plurality of keys, wherein the received signal is transmitted from a communications unit communicatively coupled to the subscriber identification module, and the received signal is generated by the communications unit using a second key from the plurality of keys, the second key having been communicated from the subscriber identification module to the communications unit; and transmitting the authentication signal to the communications system via the communications unit.
[0010] In another aspect, a subscriber identification module is presented, comprising: a key generation element; and a signature generator configured to receive a secret key from the key generation element and information from a mobile unit, and further configured to output a signature to the mobile unit.
[0011] In another aspect, an apparatus for providing secure local authorization of a subscriber in a communication system is presented, comprising a subscriber identification module configured to interact with a communications unit, wherein the subscriber identification module comprises: a key generator for generating a plurality of keys from a received value and a secret value, wherein at least one communication key from the plurality of keys is delivered to the communications unit and at least one secret key from the plurality of keys is not delivered to the communications unit; and a signature generator for generating an authorization signal from both the at least one secret key and from an authorization message, wherein the authorization message is generated by the communications unit using the at least one communication key.
[0012] In another aspect, a method for providing authentication of a subscriber using a subscriber identification device is presented, comprising: generating a plurality of keys; transmitting at least one key from the plurality of keys to a communications device communicatively coupled to the subscriber identification device and holding private at least one key from the plurality of keys; generating a signature at the communications device using both the at least one key transmitted to the communications device and a transmission message; transmitting the signature to the subscriber identification device; receiving the signature at the subscriber identification device; generating a primary signature from the received signature; and conveying the primary signature to a communications system.
[0013] In another aspect, a method for providing authentication of a subscriber using a subscriber identification device, comprising: generating a plurality of keys; transmitting at least one key from the plurality of keys to a communications device communicatively coupled to the subscriber identification device and holding private at least one key from the plurality of keys; assigning a weight to the transmission message at the communications device in accordance with a relative importance of the transmission message; generating a signature at the communications device using both the at least one key transmitted to the communications device and the transmission message; transmitting the signature to a communications system if the assigned weight to the transmission message indicates that the transmission message is unimportant; and transmitting the signature to the subscriber identification device if the assigned weight to the transmission message indicates that the transmission message is important, whereupon the subscriber identification device generates a primary signature from the received signature signal, and then conveys the primary signature to a communications system.
DETAILED DESCRIPTION OF THE DRAWINGS
[0014] [0014]FIG. 1 is a diagram of an exemplary data communication system.
[0015] [0015]FIG. 2 is a diagram of a communication exchange between components in a wireless communication system.
[0016] [0016]FIG. 3 is a diagram of an embodiment wherein a subscriber identification token provides encryption support to a mobile unit.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0017] As illustrated in FIG. 1, a wireless communication network 10 generally includes a plurality of mobile stations (also called subscriber units or user equipment) 12 a - 12 d , a plurality of base stations (also called base station transceivers (BTSs) or Node B) 14 a - 14 c , a base station controller (BSC) (also called radio network controller or packet control function 16 ), a mobile switching center (MSC) or switch 24 , a packet data serving node (PDSN) or internetworking function (IWF) 20 , a public switched telephone network (PSTN) 22 (typically a telephone company), and an Internet Protocol (IP) network 18 (typically the Internet). For purposes of simplicity, four mobile stations 12 a - 12 d , three base stations 14 a - 14 c , one BSC 16 , one MSC 18 , and one PDSN 20 are shown. It would be understood by those skilled in the art that there could be any number of mobile stations 12 , base stations 14 , BSCs 16 , MSCs 18 , and PDSNs 20 .
[0018] In one embodiment the wireless communication network 10 is a packet data services network. The mobile stations 12 a - 12 d may be any of a number of different types of wireless communication device such as a portable phone, a cellular telephone that is connected to a laptop computer running IP-based, Web-browser applications, a cellular telephone with associated hands-free car kits, a personal data assistant (PDA) running IP-based, Web-browser applications, a wireless communication module incorporated into a portable computer, or a fixed location communication module such as might be found in a wireless local loop or meter reading system. In the most general embodiment, mobile stations may be any type of communication unit.
[0019] The mobile stations 12 a - 12 d may be configured to perform one or more wireless packet data protocols such as described in, for example, the EIA/TIA/IS-707 standard. In a particular embodiment, the mobile stations 12 a - 12 d generate IP packets destined for the IP network 24 and encapsulate the IP packets into frames using a point-to-point protocol (PPP).
[0020] In one embodiment the IP network 24 is coupled to the PDSN 20 , the PDSN 20 is coupled to the MSC 18 , the MSC 18 is coupled to the BSC 16 and the PSTN 22 , and the BSC 16 is coupled to the base stations 14 a - 14 c via wirelines configured for transmission of voice and/or data packets in accordance with any of several known protocols including, e.g., E 1 , T 1 , Asynchronous Transfer Mode (ATM), IP, Frame Relay, HDSL, ADSL, or xDSL. In an alternate embodiment, the BSC 16 is coupled directly to the PDSN 20 , and the MSC 18 is not coupled to the PDSN 20 . In another embodiment of the invention, the mobile stations 12 a - 12 d communicate with the base stations 14 a - 14 c over an RF interface defined in the 3 rd Generation Partnership Project 2 “3 GPP 2”, “Physical Layer Standard for cdma2000 Spread Spectrum Systems,” 3GPP2 Document No. C.P0002-A, TIA PN-4694, to be published as TIA/EIA/IS-2000-2-A, (Draft, edit version 30) (Nov. 19, 1999), which is fully incorporated herein by reference.
[0021] During typical operation of the wireless communication network 10 , the base stations 14 a - 14 c receive and demodulate sets of reverse-link signals from various mobile stations 12 a - 12 d engaged in telephone calls, Web browsing, or other data communications. Each reverse-link signal received by a given base station 14 a - 14 c is processed within that base station 14 a - 14 c . Each base station 14 a - 14 c may communicate with a plurality of mobile stations 12 a - 12 d by modulating and transmitting sets of forward-link signals to the mobile stations 12 a - 12 d . For example, as shown in FIG. 1, the base station 14 a communicates with first and second mobile stations 12 a , 12 b simultaneously, and the base station 14 c communicates with third and fourth mobile stations 12 c , 12 d simultaneously. The resulting packets are forwarded to the BSC 16 , which provides call resource allocation and mobility management functionality including the orchestration of soft handoffs of a call for a particular mobile station 12 a - 12 d from one base station 14 a - 14 c to another base station 14 a - 14 c . For example, a mobile station 12 c is communicating with two base stations 14 b , 14 c simultaneously. Eventually, when the mobile station 12 c moves far enough away from one of the base stations 14 c , the call will be handed off to the other base station 14 b.
[0022] If the transmission is a conventional telephone call, the BSC 16 will route the received data to the MSC 18 , which provides additional routing services for interface with the PSTN 22 . If the transmission is a packet-based transmission such as a data call destined for the IP network 24 , the MSC 18 will route the data packets to the PDSN 20 , which will send the packets to the IP network 24 . Alternatively, the BSC 16 will route the packets directly to the PDSN 20 , which sends the packets to the IP network 24 .
[0023] [0023]FIG. 2 illustrates a method for authenticating a subscriber using a mobile phone in a wireless communication system. A subscriber travelling outside of the range of his or her Home System (HS) 200 uses a mobile unit 220 in a Visited System (VS) 210 . The subscriber uses the mobile unit 220 by inserting a subscriber identification token. Such a subscriber identification token is configured to generate cryptographic and authentication information that allows a subscriber to access account services without the need for establishing a new account with the visited system. A request is sent from the mobile unit 220 to the VS 210 for service (not shown in figure). VS 210 contacts HS 200 to determine service to the subscriber (not shown in figure).
[0024] HS 200 generates a random number 240 and an expected response (XRES) 270 based on knowledge of the private information held on the subscriber identification token. The random number 240 is to be used as a challenge, wherein the targeted recipient uses the random number 240 and private knowledge to generate a confirmation response that matches the expected response 270 . The random number 240 and the XRES 270 are transmitted from the HS 200 to the VS 210 . Other information is also transmitted, but is not relevant herein (not shown in figure). Communication between the HS 200 and the VS 210 is facilitated in the manner described in FIG. 1. The VS 210 transmits the random number 240 to the mobile unit 220 and awaits the transmission of a confirmation message 260 from the mobile unit 220 . The confirmation message 260 and the XRES 270 are compared at a compare element 280 at the VS 210 . If the confirmation message 260 and XRES 270 match, the VS 210 proceeds to provide service to the mobile unit 220 .
[0025] Mobile unit 220 sends the random number 240 to the subscriber identification token 230 that has been inserted inside the mobile unit 220 by the subscriber. A Secure Key 300 is stored on the subscriber identification token 230 . Both the Secure Key 300 and the random number 240 are used by a key generator 250 to generate the confirmation message 260 , a cryptographic Cipher Key (CK) 290 , and an Integrity Key (IK) 310 . The CK 290 and IK 310 are conveyed to the mobile unit 220 .
[0026] At the mobile unit 220 , the CK 290 can be used to encrypt communications between the mobile unit 220 and the VS 210 , so that communications can be decrypted only by the intended recipient of the message. Techniques for using a cryptographic key to encrypt communications are described in co-pending U.S. patent application 09/143,441, filed on Aug. 28, 1998, entitled, “Method and Apparatus for Generating Encryption Stream Ciphers,” assigned to the assignee of the present invention, and incorporated by reference herein. It should be noted that other encryption techniques can be used without affecting the scope of the embodiments described herein.
[0027] The IK 310 can be used to generate a message authentication code (MAC), wherein the MAC is appended to a transmission message frame in order to verify that the transmission message frame originated from a particular party and to verify that the message was not altered during transmission. Techniques for generating MACs are described in co-pending U.S. patent application No. 09/371,147, filed on Aug. 9, 1999, entitled, “Method and Apparatus for Generating a Message Authentication Code,” assigned to the assignee of the present invention and incorporated by reference herein. It should be noted that other techniques for generating authentication codes may be used without affecting the scope of the embodiments described herein.
[0028] Alternatively, the IK 310 can be used to generate an authentication signature 340 based on particular information that is transmitted separately or with the transmission message. Techniques for generating an authentication signature are described in U.S. Pat. No. 5,943,615, entitled, “Method and Apparatus for Providing Authentication Security in a Wireless Communication System,” assigned to the assignee of the present invention and incorporated by reference herein. The authentication signature 340 is the output of a hashing element 330 that combines the IK 310 with a message 350 from the mobile unit 220 . The authentication signature 340 and the message 350 are transmitted over the air to the VS 210 .
[0029] As seen in FIG. 2, the cryptographic key 290 and the integrity key 310 are transmitted from the subscriber identification token 230 to the mobile unit 220 , which proceeds to generate data frames for public dissemination over the air. While this technique may prevent an eavesdropper from determining the values of such keys over the air, this technique does not provide protection from attack by a rogue shell. A rogue shell can be programmed to accept the CK 290 and the IK 310 , and to then store the keys rather than purging the presence of such keys from local memory. Another method to steal keys is to program the mobile unit 220 to transmit received keys to another location. The CK 290 and the IK 310 can then be used to fraudulently bill unauthorized communications to the subscriber. This rogue shell attack is particularly effective in systems wherein the random number generated at the Home System 200 is used in a manner that is insecure, such as the case when the same generated keys are used for an extended period of time.
[0030] An embodiment that protects against a rogue shell attack uses the processors and memory in the subscriber identification token to generate an electronic signature that cannot be reproduced by a mobile unit without the insertion of the subscriber identification token.
[0031] [0031]FIG. 3 illustrates an embodiment for performing local authentication of a subscriber in a wireless communication system. In this embodiment, the subscriber identification token 230 is programmed to generate an authentication response based on a key that is not passed to the mobile unit 220 . Hence, if the mobile unit used by a subscriber is a rogue shell, the rogue shell cannot recreate the appropriate authentication responses.
[0032] Similar to the method described in FIG. 2, the mobile unit 220 generates a signature signal based upon an IK 310 that is received from the subscriber identification token 230 and a message that is to be sent to the VS 210 . However, in the exemplary embodiment, the signature signal is not passed to the VS. The signature signal is passed to the subscriber identification token 230 , and is used along with an additional key to generate a primary signature signal. The primary signature signal is sent out to the mobile unit 220 , which in turn transmits the primary signature signal to the VS 210 for authentication purposes.
[0033] HS 200 generates a random number 240 and an expected response (XRES) 270 based on knowledge of the private information held on the subscriber identification token 230 . The random number 240 and the XRES 270 are transmitted to the VS 210 . Communication between the HS 200 and the VS 210 is facilitated in the manner described in FIG. 1. The VS 210 transmits the random number 240 to the mobile unit 220 and awaits the transmission of a confirmation message 260 from the mobile unit 220 . The confirmation message 260 and the XRES 270 are compared at a compare element 280 at the VS 210 . If the confirmation message 260 and the XRES 270 match, the VS 210 proceeds to provide service to the mobile unit 220 .
[0034] Mobile unit 220 conveys the random number 240 to the subscriber identification token 230 that has been electronically coupled with the mobile unit 220 by the subscriber. A Secure Key 300 is stored on the subscriber identification token 230 . Both the Secure Key 300 and the random number 240 are used by a key generator 250 to generate the confirmation message 260 , a Cryptographic Key (CK) 290 , an Integrity Key (IK) 310 , and a UIM Authentication Key (UAK) 320 . The CK 290 and IK 310 are conveyed to the mobile unit 220 .
[0035] At the mobile unit 220 , the CK 290 is used for encrypting transmission data frames (not shown in FIG. 3). The IK 310 is used to generate a signature signal 340 . The signature signal 340 is the output of a signature generator 330 that uses an encryption operation or a one-way operation, such as a hashing function, upon the IK 310 and a message 350 from the mobile unit 220 . The signature signal 340 is transmitted to the subscriber identification token 230 . At the subscriber identification token 230 , the signature signal 340 and the UAK 320 are manipulated by a signature generator 360 to generate a primary signature signal 370 . The primary signature signal 370 is transmitted to the mobile unit 220 and to the VS 210 , where a verification element 380 authenticates the identity of the subscriber. The verification element 380 can accomplish the verification by regenerating the signature signal 340 and the primary signature signal 370 . Alternatively, the verification element 380 can receive the signature signal 340 from the mobile unit 220 and only regenerate the primary signature signal 370 .
[0036] The regeneration of the signature signal 340 and the primary signature signal 370 at the VS 210 can be accomplished by a variety of techniques. In one embodiment, the verification element 380 can receive a UAK 390 and an integrity key from the Home System 200 . When the verification element 380 also receives the message 350 from the mobile unit 220 , the signature signal can be generated and then used to generate the primary signature element.
[0037] The signature generator 360 within the subscriber identification token 230 can comprise a memory and a processor, wherein the processor can be configured to manipulate inputs using a variety of techniques. These techniques can take the form of encryption techniques, hashing functions, or any nonreversible operation. As an example, one technique that can be implemented by the subscriber identification token is the Secure Hash Algorithm (SHA), promulgated in Federal Information Processing Standard (FIPS) PUB 186 , “Digital Signature Standard,” May 1994. Another technique that can be performed by the subscriber identification token is the Data Encryption Standard (DES), promulgated in FIPS PUB 46, January 1977. The use of the term “encryption” as used herein does not necessarily imply that operations must be reversible. The operations may be non-reversible in the embodiments described herein.
[0038] The key generator 250 can also comprise a memory and a processor. Indeed, in one embodiment, a single processor can be configured to accomplish the functions of the signature generator 360 and the key generator 250 . Verification can be performed by calculating the same result from the same inputs at the verification element 380 , and comparing the calculated and transmitted values.
[0039] A subscriber identification token used in a CDMA system or a GSM system, also known as an R-UIM or a USIM, respectively, can be configured to generate the primary signature signal 370 in the manner described above, i.e., all messages generated by the mobile unit are encrypted and authenticated. However, since the central processing unit in such tokens can be limited, it may be desirable to implement an alternative embodiment, wherein a weight of importance is assigned to a message frame so that only important messages are securely encrypted and authenticated. For example, a message frame containing billing information has more need for increased security than a message frame containing a voice payload. Hence, the mobile unit can assign a greater weight of importance to the billing information message frame and a lesser weight of importance to the voice message frame. When the subscriber identification token receives the signature signals generated from these weighted messages, the CPU can assess the different weights of importance attached to each signature signal and determine a primary signature signal for only the heavily weighted signature signals. Alternatively, the mobile unit can be programmed to convey only the “important” signature signals to the subscriber identification token. This method of selective primary signature signal generation increases the efficiency of the subscriber identification token by lightening the processing load of the subscriber identification token.
[0040] The embodiments described above prevent unauthorized use of a subscriber's account by requiring a more secure transaction between the subscriber identification token and the mobile unit. Since the mobile unit cannot generate a primary signature signal without knowledge of the secret UAK, the mobile unit that is programmed to act as a rogue shell cannot misappropriate subscriber information for wrongful purposes.
[0041] The embodiments described above also maximize the processing capability of the subscriber identification token by operating on a signature signal, rather than a message. Typically, a signature signal will have a shorter bit length than a message. Hence, less time is required for the signature generator in the subscriber identification to operate on a signature signal rather than a transmission message frame. As mentioned above, the processing capability of the subscriber identification token is usually much less than the processing capability of the mobile unit. Hence the implementation of this embodiment would provide secure authentication of messages without sacrificing speed.
[0042] However, it should be noted that improvements in processor architectures occur at an almost exponential pace. Such improvements consist of faster processing times and smaller processor sizes. Hence, another embodiment for providing local authentication can be implemented wherein the primary signature signal can be generated directly from a message, rather than indirectly through a short signature signal. A mobile unit can be configured to pass a message directly to the subscriber identification token, one with the capability to generate a primary signature signal quickly, rather than passing the message to a signature generating element within the mobile unit. In another embodiment, only a limited number of messages need be passed directly to the subscriber identification token, in accordance with the degree of security needed for said messages.
[0043] It should be noted that while the various embodiments have been described in the context of a wireless communication system, the various embodiments can be further used to provide secure local authentication of any party using an unfamiliar terminal connected in a communications network.
[0044] Thus, novel and improved methods and apparatus for performing local authentication of a subscriber in a communication system have been described. Those of skill in the art would understand that the various illustrative logical blocks, modules, circuits, and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, software, firmware, or combinations thereof. The various illustrative components, blocks, modules, circuits, and steps have been described generally in terms of their functionality. Whether the functionality is implemented as hardware, software, or firmware depends upon the particular application and design constraints imposed on the overall system. Skilled artisans recognize the interchangeability of hardware, software, and firmware under these circumstances, and how best to implement the described functionality for each particular application.
[0045] Implementation of various illustrative logical blocks, modules, circuits, and algorithm steps described in connection with the embodiments disclosed herein may be implemented or performed with a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components. A processor executing a set of firmware instructions, any conventional programmable software module and a processor, or any combination thereof can be designed to perform the functions described herein. The processor may advantageously be a microprocessor, but in the alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. The software module could reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. An exemplary processor is coupled to the storage medium so as to read information from, and write information to, the storage medium. In the alternative, the storage medium may reside in an ASIC. The ASIC may reside in a telephone or other user terminal. In the alternative, the processor and the storage medium may reside in a telephone or other user terminal. The processor may be implemented as a combination of a DSP and a microprocessor, or as two microprocessors in conjunction with a DSP core, etc. Those of skill would further appreciate that the data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced throughout the above description are represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.
[0046] Various embodiments of the present invention have thus been shown and described. It would be apparent to one of ordinary skill in the art, however, that numerous alterations may be made to the embodiments herein disclosed without departing from the spirit or scope of the invention. | Methods and apparatus are presented for providing local authentication of subscribers travelling outside their home systems. A subscriber identification token 230 provides authentication support by generating a signature 370 based upon a key that is held secret from a mobile unit 220. A mobile unit 220 that is programmed to wrongfully retain keys from a subscriber identification token 230 after a subscriber has removed his or her token is prevented from subsequently accessing the subscriber's account. | 7 |
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] This application is a continuation in part of prior filed application, application Ser. No. 13/171,578, filed Jun. 29, 2011, pursuant to 35 U.S.C. 120, the subject matter of which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to the field of oil and gas drilling and in particular to apparatuses for the containment and control of the flow of hydrocarbons from oil and gas wells.
[0003] An inherent risk in oil and gas exploration is the unintended release of oil or gas into the environment. A common cause for these releases are sudden pressure variations during the drilling process (so called kicks), usually caused by influx of formation fluids into the well bore. If the formation fluids are allowed to reach the surface, well tools and other drilling material may be blown out of the wellbore. These blowouts may result in destruction of the drilling equipment and injury or death to rig personnel. The main tool to prevent spills from these pressure variations used today are blowout preventers which essentially represent sealing devices to seal off the wellbore until active measures can be taken to control the kick. However, even with blowout preventers in place, the risk of oil spills remains. Spills can still occur due to material failure of the blowout preventer resulting from excessive pressure or accidental disruption of conducting components such as riser pipes, as well as catastrophic destruction of drilling platforms. Once a spill has occurred, measures must be taken to contain it. In previously occurring oil spills those measures have included the permanent sealing of the wellbore with filling material, and capturing the spilling oil by temporary capping of the well.
[0004] It has been recognized that known blowout preventer systems are susceptible to leaks due to material failure under high pressure. Especially in deep sea oil drilling, blowout preventers are subjected to enormous stress from external hydrostatic pressure of seawater and formation fluid pressure of the wellbore. Blowout preventers commonly used today consist of many interconnected parts with gaskets meant to seal leakage of formation fluids through the sites of interconnection. An example for a typical blowout preventer used in oil exploration is U.S. Pat. No. 7,300,033. The high stress exerted on the interconnecting spaces and gaskets makes these elements sites for potential leaks. In addition, current blowout preventer systems lack the ability to detect the build up of gas at the wellbore and relay this information to drilling personnel. Further, it has been generally recognized that current systems for emergency containment and recovery of oil spills are inadequate. An example for such a system is the apparatus used during the oil spill from the Moncado oil well in the Gulf of Mexico in 2010. The apparatus used in the Moncado oil spill essentially represents a dome designed to enclose the ruptured oil pipe. At its top this dome can be connected to a riser pipe. After placement of the device over the ruptured pipe of the Moncado well, hydrates formed due to low temperature, and accumulated in the upper region of the dome, preventing oil flow from the device into the riser pipe. Since the hydrates are lighter than water they also caused the device to become buoyant and float upwards. The attempt to contain the Moncado well and recover the spilling oil using the containment structure eventually failed. Further, emergency containment systems currently in use do not have the ability to regulate oil flow in real time but can only operate on an on or off basis.
[0005] It would therefore be desirable and advantageous to provide an improved blow-out preventer and oil spill recovery management system to obviate prior shortcomings of other systems and to provide a system in which stress on the device from formation fluid pressure is minimized, which is able to detect gas build up during drilling operations at the wellbore, and which is better adapted to respond to emergency oil spills.
SUMMARY OF THE INVENTION
[0006] In some embodiments the invention relates to an apparatus for containing and controlling the flow of hydrocarbons from a bore well or other earth formation, comprising:
[0007] An apparatus for containing and controlling the flow of hydrocarbons from a wellbore or other earth formation, including a housing enclosing a receiving and distribution chamber, said receiving and distribution chamber in fluid communication with and sealably connected to a top vertical tubular member and a bottom vertical tubular member, said top and bottom tubular members extending from said receiving and distribution chamber to the exterior of said housing, wherein the top vertical tubular member having an inner tubular member comprising means for moving said inner tubular member along the axis of said top vertical tubular member, said inner tubular member adapted upon movement to sealably connect or disconnect, said bottom vertical tubular member to said top vertical tubular member, cone aperture adapted to prevent or allow the flow of liquid into said top tubular member, at least one outlet passage between the receiving and distribution chamber and the exterior of said housing, valve means adapted to permit or prevent the flow of liquid through at least one of said outlet passages and, pump means adapted to facilitate the flow of hydrocarbons through at least one of said outlet passages.
[0008] In other embodiments the invention relates to an apparatus for containing and controlling the flow of hydrocarbons from a bore well or other earth formation, including: a housing enclosing a receiving and distribution chamber, said housing comprising at least two layers, wherein the layers have a space in between them, said receiving and distribution chamber in fluid communication with and sealably connected to a top vertical tubular member and a bottom vertical tubular member, said top and bottom tubular members extending from said receiving and distribution chamber to the exterior of said housing, wherein the top vertical tubular member having an inner tubular member comprising means for moving said inner tubular member along the axis of said top vertical tubular member, wherein the inner tubular member is adapted upon movement to sealably connect or disconnect, the bottom vertical tubular member to the top vertical tubular member, a cone aperture adapted to prevent or allow the flow of liquid into the top tubular member, at least one outlet passage between the receiving and distribution chamber and the exterior of the housing, valve means adapted to permit or prevent the flow of liquid through at least one of the outlet passages and, pump means adapted to facilitate the flow of hydrocarbons through at least one of said outlet passages.
[0009] In some embodiments the invention relates to a method for containing and controlling the flow of hydrocarbons from a well bore or other earth formation using an apparatus comprising a housing enclosing a receiving and distribution chamber, wherein the housing includes at least two layers, where the layers have a space in between them, wherein the receiving and distribution chamber are in fluid communication with and sealably connected to a top vertical tubular member and a bottom vertical tubular member, wherein the top and bottom tubular members extend from the receiving and distribution chamber to the exterior of the housing, wherein the top tubular member has an inner tubular member including means for moving the inner tubular member along the axis of the top vertical tubular member, wherein the inner tubular member is adapted upon movement to sealably connect or disconnect, the bottom vertical tubular member to the top vertical tubular member; a cone aperture adapted to prevent or allow the flow of liquid into the top tubular member; at least one outlet passage between the receiving and distribution chamber and the exterior of the housing; valve means adapted to permit or prevent the flow of liquid through at least one of the outlet passages; and pump means adapted to facilitate the flow of hydrocarbons through at least one of the outlet passages, the method including the steps of bringing the apparatus in contact with a well bore to allow hydrocarbons to enter the receiving and distribution chamber through the bottom vertical tubular member.
[0010] The present invention resolves prior art problems by diverting and distributing oil flow entering the device evenly towards outlet passages and by relieving excess pressure through blowout relieve vents, thereby minimizing the stress exerted on the device from formation fluid pressure. Further, the system solves the problem of hydrate build up and other complications that may be related to temperature encountered in prior art emergency oil spill recovery systems by providing insulation of the device to maintain a standard temperature of pressure. In addition the system provides features that allow for real time management of oil flow once the system is deployed. Further, the system provides sensors for detecting gas build up at the wellbore and means to relay this information to drilling personnel, and therefore allows early detection of a possible kick in the wellbore.
BRIEF DESCRIPTION OF THE DRAWING
[0011] Other features and advantages of the present invention will be more readily apparent upon reading the following description of currently preferred exemplified embodiments of the invention with reference to the accompanying drawing, in which:
[0012] FIG. 1 is a perspective view of the system in accordance with one embodiment of the invention;
[0013] FIG. 1A is a perspective view of a hose deployment set including buoy, coiled hose canister, clamps and air supply for buoy, in accordance with one embodiment of the invention;
[0014] FIG. 2 is a vertical section view of the system in accordance with one embodiment of the invention;
[0015] FIG. 2A is a vertical section view of the core pipe with inner sleeve pipe, cone aperture and handle bar in accordance with one embodiment of the invention;
[0016] FIG. 2B is a vertical section view of the core pipe showing the sleeve pipe of FIG. 2A in the lowered position.
[0017] FIG. 3 is a horizontal section view of the system with volume channel arches in accordance with one embodiment of the invention;
[0018] FIG. 4 is a horizontal section view of the system in accordance with one embodiment of the invention;
[0019] FIG. 5 is a horizontal section view of the system with quadruple aqueduct in accordance with one embodiment of the invention;
[0020] FIG. 6 is a horizontal section view of the system with quadruple aqueduct in accordance with one embodiment of the invention.
[0021] FIG. 7 is an elevational view of the system at an onshore drilling operation in accordance with one embodiment of the invention;
[0022] FIG. 7A is a detail view of the bit of the system shown in FIG. 7 ;
[0023] FIG. 8 is a vertical section view of the system in accordance with one embodiment of the invention;
[0024] FIG. 8A is a detail view of the drill bit of FIG. 8 ;
[0025] FIG. 8B is a detail view of the encircled region of FIG. 8 showing the grabber and cutter of the drilling string;
[0026] FIG. 9 is a horizontal section view of the system with quadruple aqueduct in accordance with one embodiment of the invention;
[0027] FIG. 10 is an elevational view of the system in deployment mode in accordance with one embodiment of the invention, and
[0028] FIG. 11 is a cross sectional view of the embodiment of the device according to the invention shown in FIG. 2 taken on line A-A;
[0029] FIG. 12 is a cross sectional view of the embodiment of the device according to the invention shown in FIG. 2 taken on line A-A, showing additional details.
[0030] FIG. 12A is a detailed cross sectional view of the embodiment of FIG. 1 ;
[0031] FIG. 12B is a cross sectional view taken on line B-B of FIG. 12A ;
[0032] FIG. 13 shows the embodiment of FIG. 8 with propeller as propulsion means;
[0033] FIG. 14 is an enlargement of the encircled region of the embodiment shown in FIG. 13 ;
[0034] FIG. 15 is a schematic cross sectional view of the walling of another embodiment of the invention;
[0035] FIG. 16 is a schematic cross sectional view of the walling of another embodiment of the invention;
[0036] FIG. 17 is a vertical cross sectional view of another embodiment of the device according to the invention; and
[0037] FIG. 18 is another embodiment of the device according to the invention including a temporary shutoff valve
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0038] Throughout all the Figures, same or corresponding elements are generally indicated by same reference numerals.
[0039] Turning now to the drawing, and in particular to FIG. 1 , there is shown a perspective view of the system in accordance with one embodiment of the invention. As shown in FIG. 1 one an advantageous embodiment may include a hose deployment set for one or more output pipes and/or relief vents. The deployment set is shown in more detail in FIG. 1A . Each set comprises a hose or other conducting means 32 , an inflatable floating device 30 , a source of compressed air 31 for the inflatable floating device, and clamping means 33 to connect to receiving storage facilities. The hose terminal that is proximal to the apparatus is connected to the output pipes or relief vents whereas the distal terminal of the hose is attached to the inflatable floating device, source of compressed air and clamps. Robotic arms 7 are attached to the outside of the housing and include a tool hold 27 with tools that can be used to replace and/or repair components of the device. A sliding door 26 gives access to the robotic arm chamber. Embodiments of the invention that are used offshore, may also include propulsion means for changing the position of the device relative to a target area. Such an embodiment is shown in FIG. 13 in which the propulsion means is constructed as propeller 34 . Referring to FIG. 1 again, reference numeral 4 indicates a compartment in which lights cameras, sensors and power lines can be accommodated. Reference numeral 5 indicates the area that includes the compartment 4 and the regulatory circuit 18 . The embodiment shown in FIG. 1 also includes doors 9 providing access to the robotic arm.
[0040] FIG. 2 shows a vertical section view of the Cap and Tap system according to an embodiment of the present invention with the housing 28 enclosing the receiving and distribution chamber 14 with sensors for fluid level, volume, pressure, escaped gas meter and analyzer 14 a. On its top the receiving and distribution chamber 14 is connected to the core pipe 13 a that leads to the main viaduct 1 . The core pipe contains an inner sleeve pipe 13 b and has a cone aperture 13 c and a handle bar 13 d. On the bottom, the receiving and distribution chamber 14 is connected to the pipe threshold 17 . Hydraulic pump managed ducts 16 lead from the receiving and distribution chamber 14 to the hydraulic pump platform 15 . Hydraulic pump managed output pipes 10 lead from the hydraulic pump platform to the exterior of the housing 28 . Volume pressure blowout relief vents 8 lead from the receiving and distribution chamber to the exterior of the housing.
[0041] In the embodiment of the invention depicted in FIG. 2 the position of the inner sleeve pipe 13 can be changed by moving it along the axis of the core pipe 13 a. By moving the inner sleeve pipe 13 , operation of the invention can be changed between two alternative modes. When the sleeve pipe is in the up-position (as shown in FIG. 2 and FIG. 2A ), the cone aperture 13 c is in the closed configuration, preventing oil flow into the core pipe. In this instance, incoming oil enters the receiving and distribution chamber 14 and is distributed evenly within the chamber by the cone aperture. The oil is distributed from the receiving and distribution chamber 14 through the hydraulic pump managed ducts 16 and eventually to the output pipes 10 . The sensors 14 a of the receiving and distribution chamber 14 are connected to a regulatory circuit 18 that in turn is connected to actuators which in turn are mechanically connected to valves adapted to permit or prevent flow of oil through the blowout relief vents. In case the pressure in the receiving and distribution chamber reaches a preset value a signal is distributed by the sensors 14 a, to the regulatory circuit 18 which in turn activates the actuators to open the valves of the blowout relief vents to relief pressure. The main viaduct 1 can be opened and closed by means of open and close valves constructed as retractable shutter bars 29 . The main viaduct 1 can also be closed temporarily by a temporary shutoff valve 29 a. The temporary shutoff valve can be advantageous under conditions when an excess of escaped gas has to be vented out.
[0042] To operate the invention in the alternative mode the sleeve pipe is moved downward until it reaches the drill collar. Upon downward movement of the inner sleeve the cone aperture opens and remains in open configuration. Ideally, the inner sleeve pipe has an inner diameter relative to the outer diameter of the pipe threshold 17 that allows for a sealing engagement when the sleeve pipe is moved over the pipe threshold 17 . In this instance oil is not allowed to enter the receiving and distribution chamber 14 but is directed to the main aqueduct 1 . The sleeve pipe can either be moved pneumatically or hydraulically with a hydraulic or pneumatic mechanism. The sleeve pipe can also be moved or manually with the handle bars. In particular, the handle bars are useful to overcome unforeseen obstructions such as mud or rocks or water log or corrosion. FIG. 11 is a cross sectional view taken along the line A-A of FIG. 2 and shows a more detailed view of the regulatory circuit 18 showing individual components 18 A-G of the regulatory circuit 18 . The regulatory circuit 18 can include means, for example schematically represented by reference numeral 18 A for transmitting the presence of gas detected by the sensors 14 a.
[0043] FIG. 2B shows the sleeve pipe in the lowered position. FIG. 12 shows the hydraulic and pneumatic mechanism for moving the inner sleeve pipe.
[0044] The embodiment shown in FIG. 2 also includes means that assist in positioning the device relative to a target area e.g. a well bore. Lights 4 A and camera 4 B are positioned preferably at the lower part of the device. Centering sensors and cameras 12 are positioned in close proximity to the drill collar to aid in centering the device on the ruptured pipe. Camera and centering sensors 12 are connected to a control circuit to allow for calculation of position of the drill collar with respect to the ruptured pipe. The embodiment may also include anchoring means 11 to anchor the device to the ground once deployment is complete.
[0045] FIG. 7 shows an elevational view of the system according to the invention at an onshore drilling operation. FIG. 7 indicates where the system according to the invention would be employed instead of a conventional blowout preventer.
[0046] Another embodiment of the invention is shown in FIG. 8 . This embodiment comprises a retractable conduit pipe 24 to allow use of the invention in regular drilling operations. The retractable conduit pipe 24 of the embodiment in FIG. 8 replaces the inner sleeve pipe of the embodiment shown in FIG. 2 . During regular drilling operations the conduit pipe 24 passes through the core pipe and the pipe threshold into the wellbore. The drill collar 22 , drill string 23 and drill bit 21 are positioned within the conduit pipe 24 . During regular drilling operations the blowout relief vents 8 and the hydraulic pump managed ducts are in closed position and not in use. The embodiment shown in FIG. 8 also comprises sensor means 14 a for detecting and measuring gas leakage in the wellbore.
[0047] FIG. 8B illustrates the grabber and cutter mechanisms. The cutter cuts the string. The grabber grabs and holds the string even after it is cut by the cutter so that there will be no need for fishing the string later.
[0048] FIG. 10 shows an example of a method to deploy an embodiment of the invention. A scaffold 20 as shown in FIG. 10 may be placed over the target site e.g. a ruptured pipe. The apparatus is then lowered into the scaffold towards the ruptured pipe. Eyes for cable hooks 3 (see FIG. 1 ) may be used to attach means for suspending the apparatus. Cameras, lights and pipe centering sensors are used to guide the apparatus to the ruptured pipe. Once the ruptured pipe has been encapsulated by the pipe threshold, anchor means are activated to anchor the apparatus to the ground. A person with skill in the art will appreciate other methods to bring the apparatus into contact with a target site such as a ruptured pipe. For example, the apparatus may be lowered to the target site without the help of a scaffold depending on conditions such as water drift, wind, etc at the site of deployment. In case no scaffold is used, the apparatus may be lowered to the ocean floor manually or with the assistance microcontrollers.
[0049] The housing of the system can be designed using any material or arrangement of components which are commonly used in the art to achieve maintenance of structural integrity under conditions commonly encountered during oil exploration. A preferred material for the housing is solid-state stainless steel. The housing can comprise several layers. In another embodiment shown in FIG. 15 , the housing comprises three layers, internal housing layer A, middle layer B and external layer C. The space between layer A and B accommodates the connectivity apparatus. In order to remove air pockets that could destabilize the CAT system the space between layer A and B may be filled with injectable plastic material to remove air pockets. The space between layer B and C can be filled with injectable insulation to maintain standard temperature of pressure. In another preferred embodiment shown in FIG. 16 , the housing comprises a fourth layer D in addition to the three layers shown for the embodiment of FIG. 15 above. In the embodiment of FIG. 16 , the space between layer C and D can be filled with ballast material such as water or mud.
[0050] The number and shape of the receiving and distribution chamber(s) may vary. One preferred embodiment shown in FIG. 2 has a single chamber wherein the shape of the inner surface of the chamber resembles that of an open torus with the top and bottom opening of the torus forming the attachment points for the core pipe and the pipe threshold respectively. In another embodiment shown in FIG. 5 and FIG. 6 , four receiving and distribution chambers may be present. In the embodiment shown in FIG. 5 and FIG. 6 the inner surface of each individual receiving and distribution chamber represents that of an ellipsoid. All four chambers are in fluid communication with each other and are sealably connected to the core pipe on their top and to the pipe threshold on their bottom.
[0051] In a particular embodiment, the receiving and distribution chambers may also include sensor means for measuring the pressure and flow of gas or oil in the chamber. The sensor means may be any structure or device known in the art to measure the pressure of liquids or gas including but not limited to piezzoresistive, capacitive, electromagnetic, piezoelectric, optical or potentiometric sensors.
[0052] The number of output pipes and blowout relief vents may vary in different embodiments. An example of an embodiment with 8 output pipes and 8 blowout relief vents is shown in FIG. 3 and FIG. 4 . FIG. 3 and FIG. 4 show that one advantageous way of arranging the output pipes and relief vents with regard to the receiving and distribution chamber is to use substantially even spacing between each output pipe and between each relief vent respectively. However, the spacing between each of the output pipes and between each of the relief vents does not have to be even.
[0053] The cone aperture may be any device or structure that is able to alternatively allow or prevent oil flow into the main aqueduct and which achieves the purpose of distributing incoming volume evenly when in a configuration to prevent oil flow into the main aqueduct. In one preferred embodiment the cone aperture comprises triangular members that are hingedly attached to the outside of the core pipe in such a way that when the edges of the triangular members are in contact with each other flow of oil or gas through the core pipe is prevented. In one embodiment the cone aperture may also include sensor means adapted to measure pressure and volume distribution of liquid or gas entering the receiving and distribution chamber. The sensor means may be any structure or device known in the art to measure the pressure of liquids or gas including but not limited to piezzoresistive, capacitive, electromagnetic, piezoelectric, optical or potentiometric sensors. In yet another embodiment, parts of the members comprising the cone aperture may be magnetic such as to facilitate bringing the edges of the individual members in contact with each other.
[0054] The means for moving the inner sleeve pipe can be any device or structure known in the art to achieve moving the sleeve pipe, including but not limited to hydraulically operated systems.
[0055] While the invention has been illustrated and described as embodied in blow-out preventer and oil spill recovery management, 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. The embodiments were chosen and described in order to best explain the principles of the invention and practical application to thereby enable a person skilled in the art to best utilize the invention and various embodiments with various modifications as are suited to the particular use contemplated. | An apparatus for containing and controlling the flow of hydrocarbons from a bore well or other earth formation includes a housing enclosing a receiving and distribution chamber, receiving and distribution chamber is in fluid communication with and sealably connected to a top vertical tubular member and a bottom vertical tubular member, wherein the top and bottom tubular members extend from the receiving and distribution chamber to the exterior of said housing. The apparatus further includes a cone aperture adapted to prevent or allow the flow of liquid into the top tubular member, at least one outlet passage between the receiving and distribution chamber and the exterior of the housing, valve means adapted to permit or prevent the flow of liquid through at least one of said outlet passages, and pump devices adapted to facilitate the flow of hydrocarbons through at least one of said outlet passages. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to rotating X-ray anode tubes and in particular to the joining of the anode disc to the anode stem.
2. Description of the Prior Art
The anode assembly of a rotating X-ray anode tube consists of an anode disc comprising a tungsten-rhenium alloy target joined to a base, or substrate, comprising either a molybdenum or molybdenum-tungsten alloy. The anode disc is joined to a stem which, in turn, is attached to the rotor of an induction motor. The stem may be of columbium.
A method for joining the substrate to the stem includes cold forming followed by a heat treatment to produce a diffusion bond between the components. However, to achieve a good diffusion bond one must practice good process steps of adhering to precise measurements and adherence to good cleanliness habits. The dimensions of the outside diameter of the stem and the inside diameter of the hole in the substrate must be maintained very closely. Ideally an interference fit is provided to produce a good diffusion bond. Such a fit is dependent upon degree of surface finish, and surface cleanliness. Should the initial extent of intimate contact between the stem and the substrate of the disc be less than desired, a poor, or incomplete, diffusion bond may result. An incomplete bond between the stem and the disc constitutes a structural flaw. Such a flaw, under the influence of rotational stresses and, more importantly, cyclic thermal stresses can nucleate a catastrophic failure of the anode disc.
It is therefore an object of this invention to provide a new and improved method for joining the stem to the substrate of the disc of an anode assembly.
Another object of this invention is to provide a two step inertia welding process to make anode assemblies for rotating X-ray anode tubes.
Other objects of this invention will, in part, be obvious and will, in part, appear hereinafter.
SUMMARY OF THE INVENTION
In accordance with the teachings of this invention there is provided a new and improved method for joining the stem to the substrate of the disc in an anode assembly for a rotating X-ray anode tube. The stem and the substrate are positioned in inertia welding apparatus in a manner whereby the surfaces to be welded together are in an abutting relationship with each other. The substrate is preheated to an elevated temperature by the application of a first predetermined flywheel moment of inertia, a first predetermined axial force and a first predetermined spindle speed to the respective positioned components. In essence the substrate is preheated by frictional energy. Thereafter, the components (stem and substrate) are joined together by a weld joint formed by inertia welding. The inertia welding is accomplished by the application of a second predetermined flywheel moment of inertia, a second predetermined axial force and a second predetermined spindle speed. The first and second flywheel moments of inertia are the same, the first axial force is less that the second axial force and the first spindle speed is greater than the second spindle speed.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevation view, in cross-section, of a disc of an anode assembly.
FIG. 2 is a side elevation view, in cross-section, of a stem of an anode assembly.
FIG. 3 is a side elevation view, in cross-section, of an anode assembly.
DESCRIPTION OF THE INVENTION
With reference to FIG. 1, there is shown a disc 10 suitable for use in rotating X-ray anode tubes. The disc 10 comprises a base or substrate 12 which has a saucer-like configuration of a central portion 14 and an integral outer portion 16. The central portion 14 has inner and outer surfaces 18 and 20, respectively. The integral outer portion 16 has inner and outer surfaces 22 and 24, respectively. Centrally disposed on the inner surface 18 is a raised boss 26 which is integral with the central portion 14. The raised boss has a central axis which is coincident with the central axis of the disc 10. Additionally the raised boss has a cross-sectional surface area 27. The material of the substrate or base 12 may be of molybdenum, a molybdenum based alloy such as Mo-5w or other suitable material capable of withstanding from 1000° C. to 1350° C. operating temperatures, rapid heating cycles from room temperature to operating temperature and returning to room temperature, and a minimum of 10,000 cycle operation. The molybdenum substrate may comprise material which is forged and recrystallized or may be made from pressed, sintered and forged stock.
Disposed on, and joined to, the outer surface 24 of the outer portion 16 of the disc 10 is a layer 28 of a metal suitable to act as an X-ray target. The metal may be of tungsten or a tungsten alloy. A suitable tungsten alloy is tungsten alloyed with from 3% to 10%, by weight, rhenium.
Referring now to FIG. 2, there is shown a stem 30 made of a suitable metal such, for example, as columbium. Other suitable materials are columbium alloys such, for example, as Cb291, Cb103 and Cb-1Zr. The stem 30 may have an interior wall surface 32 which defines an interior chamber which reduces the thermal conductivity of the stem. The chamber has a longitudinal axis coincidal with the longitudinal axis of the stem 30. The stem 30 has an integral solid end portion 34. The end portion 34 has a surface 36.
With reference to FIG. 3, the stem 30 is joined to the disc 10 by an inertia welding process. The inertia welding process joins the two components together at their respective surfaces 36 and 27. The conventional inertia welding process embodies application of pressure in one step. Therefore, since molybdenum and its alloy material, which comprises the material of the disc 10, has a relatively high ductile-to-brittle transition temperature, it is necessary to preheat the disc 10 to a temperature of from about 200° C. to about 400° C. prior to the application of pressure to accomplish the weld. The range of axial pressure required for successful inertial welding of the components is from about 35000 psi to about 50,000 psi. The flywheel moment of inertia for the stem 30 is from 9 lb-ft 2 to 19 lb-ft 2 . The range of rotation for the stem 30 is from 1400 rpm to 2800 rpm. The total upset is approximately 0.4 inch and the metal lost, or total shorting of the stem 30 is 0.2 ± 0.1 inch.
Employing the above inertia welding parameters, an excellent weld joint 40 is achieved. Examination of the weld region reveals the material in the region of the weld joint 40 to be fine grain structure. The weld joint is substantially free of voids and internal stresses which are prevalent in prior art assemblies made by other manufacturing process techniques.
A two step inertia welding process may also be practiced. By employing the two step process one eliminates the need to preheat the disc 10 separately. In the first step, a high spindle speed is employed for rotating the stem 30 and a low axial force is employed to heat the disc 10 by friction. In the second step, a lower spindle speed is employed in conjunction with a higher axial force to join the stem 30 to the disc 10 by inertia welding. The weld joint 40 which results again exhibits excellent physical characteristics. The total amount of upset is about 0.4 inches. The metal lost, from the stem 30 is 0.2 ± 0.1 inch.
The following Table summarizes the conditions for the two step inertia welding process:
Table______________________________________Parameter Minimum Maximum Preferred______________________________________Flywheel Moment 9.0 19.0 9.0of Inertia (lb-ft.sup.2)First Axial Force 3,100 4,500 3,500(lbs.)First Spindle Speed 4,000 4,800 4,500(RPM)Second Axial Force 11,000 13,250 12,500(lbs.)Second Spindle Speed 250 500 400(RPM)Upset 0.2 0.6 0.4(inches)______________________________________
The above values for the parameters have resulted in excellent weld joints when the surfaces 27 and 36 are of the order of 0.4418 inch 2 (three-fourth inch diameter). The weld energy during the friction heating cycle for the disc 10 is of the order of 65,000 lb-ft per square inch.
The effectiveness of the novel welding process of this invention was demonstrated by experiments in which weld samples were purposefully pulled to failure. In all instances, failure occurred entirely within either the molybdenum portion or the columbium alloy portion of the sample well away from the weld interface. | A two step inertia welding process is employed to join the stem to the substrate of a disc thereby forming an anode assembly for a rotating X-ray anode tube. The abutting surfaces to be joined are rubbed together to heat the substrate to an elevated temperature, at which time the weld joint is formed by inertia welding. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is related to the following applications: U.S. Ser. No. 09/343,759; U.S. Ser. No. 09/345,090; U.S. Ser. No. 09/345,089; U.S. Ser. No. 09/343,760; U.S. Ser. No. 09/345,088; U.S. Ser. No. 60/141,688; and U.S. Ser. No. 60/141,690; and claims benefit to these provisional applications; all filed on Jun. 30, 1999, and to and U.S. Ser. Nos. 09/607,032, and 09/606,559, filed on even date herewith, entitled “Tampon Having Apertured Film Cover Thermobonded to Fibrous Absorbent Structure” and “Tampon For Feminine Hygiene And Process And Apparatus For Its Production”, respectively.
FIELD OF THE INVENTION
The invention relates to a sealing roller, particularly for a device for producing a tampon for feminine hygiene as well as a method for producing a tampon.
BACKGROUND OF THE INVENTION
Friese, U.S. Pat. No. 4,816,100 discloses a method and a device for producing a tampon for the feminine hygiene. The method includes sectioning a fluid permeable and at least partially thermoplastic material and heat sealing it onto an absorbent nonwoven fiber material or fleece web. Individual sections of the absorbent are severed from the fleece web supply and are wound onto themselves to form a tampon blank having a withdrawal cord. Thereby the fluid permeable cover material is positioned on the circumference of the tampon blank and surrounds it essentially completely. Finally, the tampon blank is pressed radially into the final shape of the tampon. Friese also employs a sealing roller to heat sealing the cover material onto the fleece web or the fleece web section. The sealing roller of Friese comprises heatable sealing elements that are spaced apart around the circumference of the sealing roller. Insulating means are arranged between these sealing elements. Thus, the sealing roller sealing elements and insulating elements alternate about the surface of the sealing roller in the direction of rotation.
Wilkes et al., U.S. Pat. No. 5,634,914, discloses multilimbed regenerated cellulose fibers which patentee claims provide high absorbency and a cotton-like handle. These tampons are described as having good stability and absorbency. Longitudinally-expanding tampons having these fibers are described as having less expansion than conventional longitudinally-expanding tampons.
Finally, Nguyen et al., WO97/23185 discloses tampons that can expand in the presence of high humidity after insertion into a user's body to prevent early bypass leakage from occurring. This tampon is a substantially cylindrical mass of compressed fibers enclosed within a fluid-permeable cover. The tampon has a stability of at least about 15 N, and is capable of radially expanding upon exposure to a humid environment. The radius increases by at least about 10% after 15 minutes to 90% relative humidity at 40° C. Particularly useful in this tampon are multilimbed fibes such as those in Wilkes et al. These fibers are relatively stiff to help the early expansion of the tampons.
Unfortunately processing these fibers causes difficulty, especially when a fibrous web having stiff fibers, such as the multilimbed fibers of Wilkes, are exposed to unexpected or undesired delays during manufacture. Such delays can allow previously calendered or compressed fibrous webs to bloom or expand, possibly due to humidity, as described in Nguyen et al. This expansion can cause jams or other undesirable process interruption.
Therefore, what is needed is a device and process to produce a high-quality tampon that secures a sufficient calendering of the fibrous fleece web for fibers that are otherwise hard to maintain in a compressed condition at a low cost.
SUMMARY OF THE INVENTION
An apparatus for thermally bonding a cover material onto an absorbent, fibrous web has a substantially cylindrical, rotatable sealing roller and a rotatable anvil roller disposed adjacent the sealing roller to provide a nip therebetween. The cover material and fibrous web can be sealed and calendered in the nip of this apparatus. The sealing roller includes a sealing element and an ironing element, and both of these elements have thermally conductive material and a leading and a trailing end in the direction of rotation. The sealing roller has at least one pair of sealing and ironing elements positioned sequentially on the circumferential surface of the sealing roller in the direction of rotation. At least one end of the ironing element is thermally insulated from an adjacent end of an adjacent sealing element.
The process for producing a tampon includes the following steps: a) applying a cover sheet to a fibrous web; b) passing the fibrous web and cover sheet combination through the nip of a sealing roller and an anvil roller; c) applying heat to a first portion of the combination at a first temperature range sufficient to bond the cover sheet to the absorbent web; and d) applying heat to a second portion of the combination at a second temperature range insufficient to bond the cover sheet to the absorbent web and sufficient to calender the fibrous web. The sealing roller provides heat at both the first and second temperature ranges to the cover sheet and fibrous web combination.
Again, it is an object of the invention to provide a device and a process to produce a high-quality tampon that secures a sufficient calendering of the fibrous fleece web for fibers that are otherwise hard to maintain in a compressed condition at a low cost device for producing a high-quality tampon which secures a sufficient calendering of the fleece web for fibers which are hard to calender at low cost. This object is solved by the apparatus including the sealing roller and the process of the present invention.
BRIEF DESCRIPTION OF THE INVENTION
FIG. 1 shows diagrammatically in cross-section an embodiment of the inventive sealing roller.
FIG. 2 shows in an perspective view another embodiment of an inventive sealing roller and a fleece web section with cover material sealed onto it.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
In order to form the fleece web into the desired fleece thickness and fleece intensity, the fleece web usually is calendered, i.e., pressure and temperature are applied to it. Depending from the kind of fibers used for the fleece web, it turned out to be problematic that the fleece web is not sufficiently treated by standard calendering so that only a“subcalendering” takes place. In order to achieve the desired fleece thickness and intensity of the fleece web, some fibers, especially the fibers which are preferred because of their higher absorptive capacity, require several calendering steps which in the production process is complicated and, thus, expensive.
According to the invention, the sealing roller having at least one sealing element located at the circumference of the se ling roller comprises at least one heatable ironing element consisting of thermally conducting material that is thermally separated at at least one end from at least one adjacent sealing element. “Thermally separated” in this case means that there is essentially no, or in comparison with the relevant heating energies or energy differences, no considerable heat transport between the elements, so that the elements are at least largely insulated against each other.
Thus, it is achieved that pressure and temperature are applied to the fleece web at its entire length by the sealing roller. In addition to the original object of the sealing roller, namely the sealing of cover material onto the fleece web, the fleece web is ironed and calendered without requiring a further process step or an additional device for the already complex and expensive processes or process machines, respectively. Even hard to calender fibers are reliably and durably formed into the desired shape by the repeated ironing or calendering respectively.
The fleece web may include any absorbent materials that are capable of absorbing and/or retaining liquids (e.g., menses). The absorbent structure can be manufactured in a wide variety of sizes and shapes and from a wide variety of liquid-absorbing materials. A representative, non-limiting list of useful materials includes cellulosic materials, such as rayon, cotton, wood pulp, creped cellulose wadding, tissue wraps and laminates, peat moss, and chemically stiffened, modified, or cross-linked cellulosic fibers; polymeric materials, such as polyester fibers, polyolefin fibers, absorbent foams, absorbent sponges, superabsorbent polymers, absorbent gelling materials; formed fibers, such as capillary channel fibers and multilimbed fibers; combinations of materials, such as synthetic fibers and wood pulp including coformed fibrous structures (e.g., those materials described in Anderson et al., U.S. Pat. No. 4,100,324); or any equivalent material or combinations of materials, or mixtures of these. However, the present invention is particularly useful for processing fleece webs containing multilimbed fibers, such as those disclosed in Wilkes, U.S. Pat. No. 5,634,914, the disclosure of which is herein incorporated by reference.
Useful cover materials used in conjunction with the present invention will be recognized by the ordinarily skilled practitioner. Known cover materials include woven, knit, and nonwoven fabrics; two-dimensional and three-dimensional apertured films; polymeric nets; and the like. Preferably, the cover material is a nonwoven fabric or a three-dimensional apertured film. Such nonwoven materials are disclosed in Friese, U.S. Pat. No. 4,816,100, the disclosure of which is herein incorporated by reference. In addition, the apertured film cover of the present invention can be manufactured by standard processes known to those of ordinary skill in the art. For example, the base film that is to be apertured can be extruded, cast, or blown to form the film. The base film can be a single formulated polymeric material or blend, or it can be a laminated or multi-layered material such as described in commonly assigned, co-pending applications to Johnson et al., U.S. Ser. No., 09/345,090, and Gell et al., U.S. Ser. No., 09/345,089, the disclosures of which are herein incorporated by reference. Useful technology to form these films will be easily recognized by those of ordinary skill in the art. The base film can then be apertured by any useful process. Several examples include hot air aperturing, and water jet aperturing. Examples of these processes are disclosed in Curro, U.S. Pat. No. 4,695,422; Turi, U.S. Pat. No. 5,567,376; and Mullane, U.S. Pat. No. 4,741,877; the disclosures of each of these patents are hereby incorporated by reference. The resulting apertured film can be coated, for example as described in commonly assigned, co-pending application U.S. Ser. No., 09/345,088, filed Jun. 30, 1999, entitled“Tampon with Cover and Nonionic Surfactant”, and/or slit to a desired width for use in manufacturing a tampon.
In a preferred embodiment, the rear end of the at least one ironing element, as seen from the rotating direction of the sealing roller, is in thermal contact with the sealing element positioned behind the ironing element in the rotating direction and the front end in the rotating direction of the at least one ironing element is separated from the heatable sealing element which is located in front of the ironing element when seen from the direction of rotation. Thus, the ironing element is heated indirectly via the thermal contact of the sealing element. An additional heating device for the ironing element is not required. Moreover, the temperature of the ironing element is automatically adapted to the desired temperature predetermined or required for the heat sealing. The temperature applied to the fleece web slowly decreases from the highest temperature at the sealing element adjacent an insulating element or space to the front end of the ironing element and finally to the rear end of the ironing element to constantly calender the fleece web.
It is additionally guaranteed that a maximum temperature of the ironing element is not exceeded in the area in which a heat sealing of the cover material is to be prevented. An undesirable heat sealing of the cover material onto the fleece web is prevented and at the same time the fleece web material is ironed and calendered whereby a remarkably improved fiber structure of the fleece web is achieved.
The material of the ironing element may be chosen from numerous thermally conducting materials. In general, metals, in particular aluminum, are the preferred materials. Depending on the choice of material and the corresponding heat conductivity, the course of temperature or the temperature gradient respectively may be determined in case of an above-mentioned partial thermal contact and optimally adapted to the material in use of either the fleece web and the cover material.
The thermally separated ends of the ironing element and the sealing element are preferably spaced apart in a predetermined distance so that an insulating air aperture is formed. it is also possible to place an insulating element between the thermally separated elements. Preferably, the sealing element and the ironing element are not completely thermally separated. However, the desired level of insulation may be determined in relation to the chosen spaces between the elements or the applied insulating elements. The heat conductivity or the heat contact respectively of the ends of the ironing element and the sealing element being in thermal contact may considerably be improved if the ironing element and the sealing element at least partially overlap and/or are at least partially interlocked. The overlapping may be realized wherein the end portion of the sealing element is graded or inclined and is located below or above a correspondingly formed end portion of the ironing element and is engaged with it. This overlapping may also be regarded and designated as a“radial interlocking”. A second possibility is an at least partial interlocking of both elements at the outer surface, in general in a coaxial rotating direction of the sealing roller.
In a preferred embodiment, the sealing roller comprises two diametrically opposed sealing elements and two diametrically opposed ironing elements. This results for usual lengths of the cover material, which is applied in the form of strips of the fleece web section, respectively, in a simple and easy-to-realize geometry and dimension of the sealing roller. Thus, the desired geometrical arrangement of the ironing elements and the sealing elements is secured without requiring a great curvature of the surfaces of the elements resulting from a sealing roller having a small diameter. Naturally, it is possible to arrange only one sealing element and one ironing element or more than two sealing elements and two ironing elements alternately. The dimension of the sealing roller increases with the number of sealing and ironing elements provided for, since the circumferential length of the single elements depend from the geometry of the materials to be treated, the cover material and the fleece web section, as explained above.
Preferably, the temperature of the sealing elements is adjustable by a control to allow adjustment of the sealing element temperature to maintain it at a desired target temperature. Appropriate thermal sensors may be used to monitor the temperature. The adjustable temperature control allows the device to be adapted to the materials to be processed, so that a variety of fibers and cover materials such as those materials described above may be processed in a high quality manner.
In another embodiment, in addition to the sealing elements, the ironing elements are directly heatable. Thus, further possibilities for the temperature control of the ironing elements exist, the ironing elements especially have a constant temperature without any temperature gradient along their entire area in care this is desired for the final product to be processed. In such an embodiment, it is likely that both ends of each ironing element are thermally separated from adjacent sealing elements.
The invention further relates to a method for producing a tampon for feminine hygiene. In particular, it relates to a method involving thermally sealing an at least partially thermoplastic cover material to a fleece web at a desired sealing temperature. The method according to the invention also provides for ironing the fleece web at an ironing temperature at a location between the areas of the cover material that are sealed whereby the maximum ironing temperature does not exceed the sealing temperature. In the areas in which the ironing element works on the cover material, the ironing temperature should not be high enough to cause unintentional sealing or damage to the cover material. As described above in connection with the device according to the invention, by such method, the fleece web is at the same time calendered over its surface by the required sealing process, i.e., pressure and temperature are applied. The desired fleece web structure and fleece web thickness is secured without the requirement of a new process station and additional devices.
The preferred sealing temperature is 140° C. for the preferred fleece web containing cotton and rayon or rayon blends and a cover material containing polyethylene. This provides a reliable heat sealing of the materials in use. The cover material is reliably bonded with the fleece web section in the desired bond region while the rest of the cover material attains a temperature that does not cause it to bond or otherwise be damaged.
In another embodiment of the method according to the invention, the ironing temperature is essentially constant which is preferably realized by a separate heating of the ironing element. With this method, one end of the ironing element may be in thermal contact with the sealing element leading at least in a partial area of the ironing element to a temperature gradient or the sealing element may be thermally completely separated, the latter being the preferred variation.
FIG. 1 shows an embodiment of an inventive sealing roller 1 having two sealing elements 10 arranged diametrically facing each other and two ironing elements 20 arranged between the sealing elements 10 , said ironing elements 20 diametrically facing each other. The circumferential length of the sealing elements 10 corresponds exactly to the length of a range of a fleece web 100 to be sealed onto the cover material 200 .
The sealing elements 10 as well as the ironing elements 20 are made of a thermally conductive material. A representative, non-limiting list of materials includes metals such as steel, including stainless steel, mild steel, tool steel, and the like; and aluminum. Useful stainless steels include the 300 series including 303 , 304 , and 316 ; the 400 series, and the 800 series. Useful mild steels include 1018 and 1020 . Useful aluminum alloys include the 2000 series including 2024 ; the 3000 series including 3003 ; the 5000 series including 5052 and 5080 ; the 6000 series including 6061 , 6063 , and 6082 ; and the 7000 series including 7075 . These materials can be coated with appropriate coatings to protect the sealing element from corrosion and wear and to reduce the likelihood of the sealed material from adhering to the tooling surfaces. Such materials will be recognized by those of ordinary skill in the art.
Heating elements are associated with the sealing elements 10 in a manner to provide well-controlled heat to the sealing bars 16 . Preferably, the heating elements controllable to provide a heat accuracy of +/− 5° C., more preferably, about +/− 2° C. This can be achieved by placing, e.g., two heating elements symmetric to a middle plane of the sealing element 10 , or three or more elements in appropriate locations on the sealing element. Alternatively, it is possible to employ a single plate heating element or to incorporate conduits within the sealing element 10 to accommodate a circulated heating fluid. In addition, a temperature control element, such as a thermocouple, can be provided close to the sealing surfaces, e.g., at the middle plane of the sealing element 10 .
The ends 22 of the ironing elements 20 which, in the direction of rotation of sealing roller 1 , marked by arrow x, are positioned at the rear end, are in thermal contact with each sealing element 10 positioned back of it. The ends of the ironing elements 20 being the front ends 21 in the direction of rotation are thermally separated from each sealing element 10 positioned in front of it. The thermal separation can be simply realized by an air gap. In the current embodiment, however, the use of a high heat insulating plastic element 15 is intended.
In operation the sealing elements 10 are heated up to a temperature of 140° C. Via a thermal contact 30 heat energy is transferred from the sealing element 10 to the ironing element 20 so that each ironing element 20 has also a temperature of 140° C. at its rear end in close proximity to the thermal contact 30 . The ironing elements 20 show a temperature gradient because of the existing cooling so that in the current embodiment there is a temperature of about 80° C. at a front end 21 of each of the ironing elements 20 being separated from the sealing element 10 next to it by the insulating elements 15 .
A pressure roller 50 presses the fleece web 100 against the sealing roller so that the cover material 200 is securely sealed onto the fleece web by sealing elements 10 . Furthermore, it is provided for another transport and/or driving roller 60 that drives the fleece web 100 and/or holds it in the desired position.
FIG. 2 shows a perspective view of a further embodiment of an inventive sealing roller as well as a fleece web auction 105 with a strip of cover material 200 sealed onto it. The sealing elements 10 comprise sealing bars 16 arranged in transverse rows and at distances from one another with said sealing bars projecting about 0.3 cm from a base 17 of the sealing elements 10 .
The ironing elements 20 are not shown in FIG. 2, they merely consist of circle segments with a substantially smooth but curved surface which can be inserted into the sealing roller 1 . By a possible exchange of the ironing elements 20 the temperature and especially the temperature gradient of the ironing elements can be adapted to the desired object and the used materials, respectively in dependence on the material and its thermal conductivity. As shown in the embodiment of FIG. 1, the thermal contact is provided for between the ends being the rear ends of the ironing elements 20 in the direction of rotation x and the respective sealing elements 10 positioned back of it whereas the ends being the front ends 21 of the ironing elements 20 in the direction of rotation x are separated from the respective sealing elements 10 positioned in front of it after the ironing elements having boon inserted into the sealing roller 1 .
It is again to be stated that in the scope of the invention further variations of the sealing bars are possible and applicable. In addition to sealing the cover to the fleece web, the sealing bars 16 of the sealing element 10 can extend beyond the cover material to additional compress or calender the fleece web. This provides further beneficial calendering to stiff fibers that may be included in the fleece web.
The drawings are merely diagrammatical and not in the real ratio of dimensions so that no limitations can be deducted from the concrete dimensions.
The features disclosed in claims, specification and drawings can be substantial for the invention, either solely or in any possible combination. | An apparatus for thermally bonding a cover material onto an absorbent, fibrous web has a substantially cylindrical, rotatable sealing roller and a rotatable anvil roller disposed adjacent the sealing roller to provide a nip therebetween. The cover material and fibrous web can be sealed and calendered in the nip of this apparatus. The sealing roller includes a sealing element and an ironing element, and both of these elements have thermally conductive material and a leading and a trailing end in the direction of rotation. The sealing roller has at least one pair of sealing and ironing elements positioned sequentially on the circumferential surface of the sealing roller in the direction of rotation. At least one end of the ironing element is thermally insulated from an adjacent end of an adjacent sealing element. | 1 |
FIELD OF THE INVENTION
The present invention provides a method for preparing oligomeric aliphatic diols, polycarbonatediols based thereon and NCO-terminated prepolymers obtainable therefrom, and also the use thereof to prepare polyurethanes.
BACKGROUND OF THE INVENTION
Aliphatic polycarbonate diols have been known for a long time. They can be prepared from non-vicinal diols by reaction with diaryl carbonates (DE-OS 19 15 908), dialkyl carbonates (DE-OS 25 55 805), dioxolanones (DE-OS 25 23 352), phosgene (DE-OS 15 95 446), bischloroformates (DE-OS 8 57 948) or urea (Angew. Chem. 92 (1980) 742). From among the many diols described for use in the literature, only 1,6-hexanediol or compounds derived from 1,6-hexanediol have been widely used on an industrial scale. Thus, for example, high-quality polyurethane elastomers and also lacquers are prepared using polycarbonatediols which are based on 1,6-hexanediol.
The resistance to hydrolysis of polyurethanes prepared from these types of polycarbonatediols is particularly outstanding. It exceeds that of analogous compounds made from polyadipatepolyols by far. Pure hexanediolpolycarbonates with number-average molecular weights of 500 to 5000 are waxy substances with a softening temperature range of approx. 45 to 55° C., depending on the molecular weight. Accordingly, the polyurethanes prepared from these have an elevated shear modulus at low temperatures, i.e. they lose their flexibility. For this reason, diols were developed which were intended to compensate for this disadvantage. The following may be mentioned, for example: oligoesters based on adipic acid (DE-AS 19 64 998), oligoesters based on caprolactone (DE-AS 17 70 245) or oligomeric tetraethylene glycols (DE-AS 22 21 751) and tetrabutylene glycols.
The disadvantage with these building blocks is their more readily hydrolyzable ester group and the elevated hydrophilicity, which at the least leads to a greater swelling of the PUR molded items prepared therefrom.
Another disadvantage of polycarbonatediols based on hexanediol is the comparatively high viscosity (approx; 5000 mPas at 60° C. with a number-average molecular weight of 2000 g/mol). This can lead to problems during processing to form polyurethane molded items.
According to the disclosure in U.S. Pat. No. 4,808,691, the disadvantages mentioned can be overcome by reacting oligomeric hexanediols with diphenyl carbonate in a stoichiometric ratio such that polycarbonatediols with number-average molecular weights of 500 to 12000, preferably 700 to 6000, result, wherein the degree of oligomerization of the ether is chosen in such a way that the ratio of ether to carbonate groups is 5:1 to 1:5, preferably 3:1 to 1:3.
However, on an industrial scale, the method for preparing oligomeric hexanediols disclosed in U.S. Pat. No. 4,808,691 proves time-consuming, labor-intensive and therefore costly. The method described in detail in that document requires the separation of water of reaction by distillation, wherein an entraining agent and catalysts are also used. Naphthaline-1,5-disulfonic acid is mentioned as the preferred catalyst. Toluene, xylene, gas oil fractions, cyclohexane, chlorobenzene and the oxepane also being formed as a secondary product are used as entraining agents, wherein the formation of this product can be slightly suppressed.
Working up after reaching the desired degree of oligomerization, detectable from the amount of water formed, is performed, according to U.S. Pat. No. 4,808,691, in such a way that the reaction mixture is cooled to 100° C. and the sulfonates present in the reaction mixture are hydrolyzed by adding 5–10% of water over 1–3 hours. The catalyst released is neutralized with aqueous alkali or ammonia, the water and other volatile components are distilled off and the catalyst, deposited as a salt, is filtered off.
On an industrial scale, however, this type of procedure has two serious disadvantages: the salt is produced in a form that can be isolated only in a very lengthy process. Typical filtration times for a batch of 3 tons are of the order of magnitude of 30 hours, wherein a change of filter is required every hour. Smaller batches of, for example, 200 kg require filtration times of approx. 5 hours.
The use of coarser filter materials which, although they facilitate faster filtration, lead to less effective separation of the salt, cannot be considered because even the smallest amount of this salt has a negative effect on the reaction of the polyols obtained to give polycarbonatediols.
Furthermore, it has been shown that oligomeric hexanediols prepared in accordance with U.S. Pat. No. 4,808,691 cannot then be used universally. Although they can react with diphenyl carbonate to give the corresponding polycarbonatediols under catalysis with bis(tributyltin) oxide or dibutyltin oxide, they do not react using heavy-metal-free catalysis, e.g. using basic salts of magnesium such as magnesium hydroxide carbonate. Even the slightest contamination with salts of sulfonic acid leads to incomplete building up of the polycarbonatediol.
The use of organotin-containing catalysts is therefore a particular disadvantage because they are not ecologically harmless.
Furthermore, oligomeric hexanediols prepared in accordance with U.S. Pat. No. 4,808,691 exhibit comparatively strong discoloration that is then carried through to the corresponding secondary-products, that is polyethercarbonatepolyols, their diisocyanate prepolymers and also the polyurethane molded items produced therefrom. This undesired discoloration represents yet another disadvantage.
Another disadvantage is that hydrolysis exclusively with water and ammonia can lead to incomplete hydrolysis of the sulfonates. If these esters decompose during the course of further reactions, then the sulfonic acid released can also cause incomplete reactions.
SUMMARY OF THE INVENTION
The present invention provides a process for preparing oligomeric diols, e.g. hexanediols, which both greatly simplifies preparation and also provides widely useable products, in particular those which can be reacted further using basic magnesium salts to give polycarbonatepolyols. In addition, the oligomeric diols obtained and their secondary products should exhibit greatly reduced discoloration.
These and other advantages and benefits of the present invention will be apparent from the Detailed Description of the Invention herein below.
DETAILED DESCRIPTION OF THE INVENTION
The present invention will now be described for purposes of illustration and not limitation. Except in the operating examples, or where otherwise indicated, all numbers expressing quantities, percentages, and so forth in the specification are to be understood as being modified in all instances by the term “about.”
The inventors herein have found that separation of the catalyst is facilitated and products with improved quality are obtained by introducing a phase separation step to give an organic and an aqueous phase during working up of the reaction mixture.
The invention provides a process for preparing oligomeric aliphatic diols in which:
1. an aliphatic diol is oligomerized in the presence of an acid catalyst and an entraining agent and the water formed is distilled off azeotropically, 2. an aqueous base is added to the reaction mixture after reaching the desired degree of oligomerization and any esters formed during oligomerization are hydrolyzed, 3. the reaction mixture is adjusted to a pH of 4.0 to 8.0 by adding non oxidising inorganic acids or the salts thereof, and, 4. after phase separation of the reaction mixture, the organic phase is isolated, dewatered and filtered.
Aliphatic diols with a molecular weight of 100 to 200, preferably 118 to 175 g/mol are used as diols. 1,6-hexanediol, 3-methyl-1,3-pentanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol or 1,10-decanediol are preferably used, particularly preferably 1,6-hexanediol or mixtures of 1,6-hexanediol with up to 50 wt. % of other diols from the group including 3-methyl-1,3-pentanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol and 1,10-decanediol.
Catalysts used for diol oligomerization in the process according to the invention are strong acids with pKa values of <3, in amounts of 0.1 to 2 wt. %. Examples are inorganic acids such as sulfuric acid, phosphoric acid, hydrogen chloride, hydrogen bromide or hydrogen iodide and their aqueous solutions as well as organic acids such as butanesulfonic acid, benzenesulfonic acid, toluenesulfonic acid, benzenedisulfonic acid and naphthalinedisulfonic acid. Napthaline-1,5-disulfonic acid is preferably used.
Toluene, xylene, gas oil fractions, cyclohexane or chlorobenzene are used as entraining agents, toluene being preferred.
Oligomerization is preferably performed at temperatures of 150 to 200° C., a pressure of 700 to 1300 mbar, preferably atmospheric pressure, for a period of 5 to 25 hours, depending on the degree of oligomerization aimed at, the amount of catalyst used and the reaction temperature. The oligomerization reaction is preferably continued to a degree of oligomerization of 1.5 to 10.
In the process according to the invention, an aqueous inorganic base is added after completion of the oligomerization reaction and azeotropic separation of the water of reaction. The reaction mixture is preferably allowed to cool to about 100° C. before adding the base. Alkali metal hydroxides are preferably used as bases, particularly preferably potassium or sodium hydroxide. The bases used preferably have a water content of 5 to 50 wt. %. The amount of base added is preferably between the stoichiometric amount required for neutralization of the acid catalyst and twice that amount.
The hydrolysis, during oligomerization of the diol, of any esters formed due to reaction of the acid catalyst with hydroxyl groups in monomeric or oligomeric diols is preferably performed by stirring for at least one hour at elevated temperature, under atmospheric pressure or elevated pressure. If hydrolysis is performed at a temperature higher than 100° C., an elevated pressure is preferably applied. In practice, it has proven especially beneficial to hydrolyze for 2 to 5 hours at 90 to 100° C. under atmospheric pressure.
After completion of hydrolysis, the pH of the reaction mixture is adjusted to within the range 4.0 to 8.0, preferably 4.5 to 7.5, more preferably 5.5 to 7.0, by adding non-oxidizing inorganic acids or their salts. The reaction mixture is preferably first allowed to cool to room temperature. Acids, the salts of which are very soluble in water, are preferred. Sulfuric acid and its acid alkali metal salts and analogous phosphoric acid and carbonic acid compounds are preferred. The acids and their salts may be used in the pure form or as a solution in a solvent, in particular water.
The pH is preferably determined by adjusting 20 ml of a mixture of 9 parts of methanol and 1 part of water to a pH of 7.0, using 1/100 N NaOH or KOH, then stirring in 10 ml of the reaction mixture and reading off the pH after 5 minutes. A commercial pH meter with pH electrodes may be used for this purpose.
When a pH of 5.5 to 7.0 has been achieved, the stirrer is switched off and the mixture is left to separate into phases, an upper organic and a lower aqueous phase. In a preferred variant, salts which are readily soluble in water, preferably common salt, are added to accelerate phase separation, following final adjustment of the pH.
The aqueous phase is separated at 30–50° C. and then residual amounts of water and the entraining agent used in the condensation phase are removed from the remaining organic phase under reduced pressure (0.001–100 mbar) at elevated temperature (90–160° C.).
After cooling to 60–100° C., preferably 75–85° C., the organic phase is filtered on a pressure Nutsche filter, coated with a fine-pored filter paper (e.g. Suprasec-1000 from Seitz). A water-clear, slightly yellow liquid is obtained. The filtration time for a 3-tonne batch is approx. 3–4 hours.
Oligomeric diols obtained according to the invention are particularly suitable for preparing polycarbonatediols. Therefore, the invention also provides a process for preparing polycarbonatediols in which an oligomeric diol obtained by the process according to the invention, optionally after adding monomeric diol, in particular 1,6-hexanediol, to adjust the degree of oligomerization, is reacted with a sub-stoichiometric amount of a carbonate donor such as diphenyl carbonate, dimethyl carbonate or phosgene in the presence of a catalyst. Diphenyl carbonate is preferably used as the carbonate donor.
The molecular weight of the polycarbonatediol can be varied between wide limits by varying the stoichiometric ratios used of oligomeric diol, monomeric diol and carbonate donor. However, polycarbonatediols with number-average molecular weights of 800 to 2800, particularly preferably 1500 to 2500 g/mol, are preferable.
Heavy metal-free catalysts are preferably used as catalysts. Magnesium salts are particularly preferable, in particular magnesium hydroxide carbonate. Further details of the method of preparation of polycarbonatepolyols according to the invention are disclosed in DE-OS 101 25 557.
If the reaction is performed in the presence of a basic magnesium salt as catalyst, this is subsequently neutralized by adding acids. Examples of acids that can be used are tartaric acid, citric acid, dibutyl phosphate, phosphoric acid, sulfuric acid and their acid salts. Sulfuric acid is preferably used to neutralize the basic magnesium catalyst, wherein a clear solution is obtained. Separation from the product of the magnesium sulfate formed is not required because this behaves in an inert manner during further reaction of the polycarbonatediol.
The invention also provides a process for preparing NCO-terminated prepolymers from polycarbonatediols obtained in accordance with the invention. Here, a polycarbonatediol obtained by the process according to the invention is reacted in sub-stoichiometric amounts with a polyisocyanate. The polyisocyanates used are preferably diisocyanates from the group including diphenylmethane diisocyanate, napthaline-1,4-diisocyanate, naphthaline-1,5-diisocyanate, durene diisocyanate, toluene diisocyanate, hexamethylene-1,6-diisocyanate and isophorone diisocyanate. 4,4′-diphenylmethane diisocyanate (e.g. DESMODUR 44M, Bayer AG) and mixtures of this with 2,4′- and 2,2′-diphenylmethane diisocyanate, wherein the proportion of the latter compounds amounts to less than 10 wt. %, are particularly preferred. Prepolymers according to the invention are characterized by substantially improved storage stability as compared with those of the art.
EXAMPLES
Preparation of Oligomeric Hexanediols
Example 1
240 kg (2069 moles) of molten hexanediol were mixed with 2.5 kg of aqueous 1,5-naphthalinedisulfonic acid (35 wt. % strength) and 10 kg of toluene, with stirring, in a 300-liter VA tank with a column and azeotropic cap, reflux condenser and distillation receiver. The temperature was raised to 170° C. and 22 kg of water distilled off over the course of 10 hours under a slight stream of nitrogen.
The tank was cooled to 100° C., evacuated and 10 kg of distilled water was drawn in under the residual vacuum. After the contents of the tank were cooled to 30° C., 0.908 kg of aqueous caustic soda solution (32 wt. % strength) were added and the mixture was heated to 100° C. over the course of 2 hours. The mixture was stirred for 1 hour at 100° C., cooled to 50° C. and 103 g of concentrated aqueous sodium hydrogen sulfate solution were then added and stirring continued for another 30 min. at this temperature. The pH of the reaction mixture was 6.4, the acid value was 0.05 mg KOH/g.
Then the mixture was cooled to 30° C. and 44 kg of aqueous common salt solution (10 wt. % strength) were stirred in intensively. After switching off the stirrer, the phases separated within approx 30 min.; the lower phase was run off. The product remaining in the tank was dewatered by applying a vacuum (1 mbar) at 140° C. for 3 hours and then cooled to 80° C. The mixture was filtered within 40 minutes on a Seitz filter with a Supra 5500 filter plate.
The yield was 190 kg, the water content of the product was 0.02 wt. %, the hydroxyl value was 466 mg KOH/g and the acid value was 0.05 mg KOH/g.
Example 2 (Comparison)
240 kg (2069 moles) of molten hexanediol were mixed with 2.5 kg of aqueous 1,5-naphthalinedisulfonic acid (35 wt. % strength) and 10 kg of toluene, with stirring, in a 300-liter VA tank with a column and azeotropic cap, reflux condenser and distillation receiver. The temperature was raised to 170° C. and 21.105 kg of water distilled off over the course of 10 hours under a slight stream of nitrogen. The experimentally determined hydroxyl value at this point in time was 431 mg KOH/g.
The tank was cooled to 100° C., evacuated and 10 kg of distilled water was drawn in under the residual vacuum. After cooling the contents of the tank to 30° C., 0.9 kg of ammonia water were added and the mixture was heated to 80° C. over the course of 3 hours. After this temperature was reached, a vacuum was slowly applied, wherein the distillation of water was triggered at 350 mbar. When 15 mbar, had been reached, the temperature was increased stepwise to 140° C. and the pressure was lowered to 2 mbar using an oil pump. Stirring was continued for a further hour under these conditions, then the temperature was reduced to 80° C. and the tank was aerated. The mixture was filtered within 320 minutes on a Seitz filter with a Supra 5500 filter plate, wherein a change of filter was required after approx. every 45 minutes.
The yield was 201 kg, the water content of the product was 0.02 wt. %, the hydroxyl value was 486 mg KOH/g and the acid value was 0.05 mg KOH/g.
Preparation of Polycarbonatediols
Example 3
3000 g of the oligomeric hexanediol prepared in example 1 were reacted with 1107 g of hexanediol and 4157 g of diphenyl carbonate in the presence of 150 mg of magnesium carbonate hydroxide pentahydrate. The reaction mixture was heated for one hour at 180° C., cooled to 120° C. and then the temperature was raised to 200° C. over the course of 6 hours, wherein the pressure was 15 mbar from approx. 120° C. To complete the reaction, stirring was continued for 2 hours at 200° C. and a pressure of <1 mbar. A total of 3652 g of phenol were distilled off. For neutralization of the basic magnesium catalyst, 175 mg of concentrated sulfuric acid were added. 4600 g of polycarbonatediol were obtained.
The OH value of the polycarbonatediol was 57.9 mg KOH/g, the acid value was 0.12 mg KOH/g, the viscosity (according to DIN 53015) was 1100 mPas (75° C.). UV-spectroscopic determination of the terminal groups showed a concentration of <0.01 wt. % of phenylcarbonato groups, 0.14 wt. % of phenoxy groups and 0.02 wt. % of free phenol.
Example 4 (Comparison)
1800 g of oligomeric hexanediol with an OH value of 501 mg KOH/g, prepared according to the process described in U.S. Pat. No. 4,808,691, were reacted with 448 g of hexanediol and 2274 g of diphenyl carbonate in the presence of 70 mg of dibutyltin oxide. The reaction mixture was heated for one hour at 180° C., cooled to 120° C. and then the temperature was raised to 200° C. over the course of 6 hours, wherein the pressure was 15 mbar from approx. 120° C. To complete the reaction, stirring was continued for 2 hours at 200° C. and a pressure of <1 mbar. A total of 2002 g (contaminated with hexanediol) of phenol were distilled off and 2520 g of polycarbonatepolyol with an OH value of 48.0 g KOH/g were obtained.
The OH value of the polyethercarbonatepolyol was increased to 56.6 mg KOH/g by adding 22.5 g of hexanediol and incorporating this into the polymer by esterification. The acid value of the product was 0.2 mg KOH/g, the viscosity (according to DIN 53015) was 900 mPas (75° C.), the color index was >999 Haze. The hexanediol post-batch thus produced the target OH value, but the elimination of phenol was incomplete. The result of this is the clear and undesirable downwards shift in the viscosity.
Example 5 (Comparison)
1556 g of oligomeric hexanediol with an OH value of 501 mg KOH/g, prepared according to the process described in U.S. Pat. No. 4,808,691, were reacted with 426 g of hexanediol and 2005 g of diphenyl carbonate in the presence of 358 mg of magnesium carbonate hydroxide pentahydrate. The reaction mixture was heated for one hour to 180° C., cooled to 120° C. and then the temperature was raised to 200° C. over the course of 6 hours, wherein the pressure was 15 mbar from approx. 120° C.
No phenol could be distilled off.
Preparation of NCO-Terminated Prepolymers
Example 6 (Comparison)
781.8 kg of pure diphenylmethane diisocyanate (DESMODUR 44 M, Bayer AG) were reacted with 1300 kg of a polycarbonatediol prepared in accordance with (comparison) example 4 for two hours at 80° C. An NCO-terminated prepolymer with an NCO content (according to DIN 53185) of 9.95 wt. % and a viscosity of 1920 mPas (70° C.) (according to DIN 53015) was obtained.
To determine the storage-stability, a sample of the prepolymer was stored for three days under N 2 at 80° C. in the drying cabinet. After this storage procedure, the viscosity had risen by approx. 26% to 2420 mPas (70° C.) and the NCO content had dropped to 9.73 wt. %.
Example 7
41.4 kg of pure diphenylmethane diisocyanate (DESMODUR 44 M, Bayer AG) were reacted with 68.6 kg of a polycarbonatediol prepared in accordance with example 3 for two hours at 80° C. An NCO-terminated prepolymer with an NCO content (according to DIN 53185) of 9.91 wt. % and a viscosity of 1910 mPas (70° C.) (according to DIN 53015) was obtained.
To determine the storage-stability, a sample of the prepolymer was stored for three days under N 2 at 80° C. in the drying cabinet. After this storage procedure, the viscosity had risen by approx. 9.5% to 2090 mPas (70° C.) and the NCO content had dropped to 9.77 wt. %.
Storage for three days at 80° C. simulates storage at room temperature for a longer period (approx. 6 months, see G. M. Barrow: “Physikalische Chemie”, part III, Vieweg Verlag, Braunschweig 1970, p. 296). The measurements performed show that prepolymers prepared from polycarbonatediols according to the invention are 3-times more storage-stable than conventionally prepared prepolymers.
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 a method for preparing oligomeric aliphatic diols, polycarbonatediols based thereon and NCO-terminated prepolymers obtainable therefrom. The inventive compounds may find use in the preparation of polyurethanes. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present invention claims priority from U.S. Patent Application No. 60/789,564 filed Apr. 6, 2006, which is incorporated herein by reference for all purposes.
TECHNICAL FIELD
[0002] The present invention relates to a multi-unit wavelength dispersive optical device, and in particular to the integration of a plurality of independent wavelength dispersive optical devices onto a single platform.
BACKGROUND OF THE INVENTION
[0003] Conventional optical wavelength dispersive devices, such as those disclosed in U.S. Pat. No. 6,097,859 issued Aug. 1, 2000 to Solgaard et al; U.S. Pat. No. 6,498,872 issued Dec. 24, 2002 to Bouevitch et al; U.S. Pat. No. 6,707,959 issued Mar. 16, 2004 to Ducellier et al; U.S. Pat. No. 6,810,169 issued Oct. 26, 2004 to Bouevitch; and U.S. Pat. No. 7,014,326 issued Mar. 21, 2006 to Danagher et al, separate a multiplexed optical beam into constituent wavelengths, and then direct individual wavelengths or groups of wavelengths, which may or may not have been modified, back through the device to a desired output port. Typically the back end of the device includes individually controllable devices, such as a micro-mirror array, which are used to redirect selected wavelengths back to one of several output ports, or an array of liquid crystal cells, which are used to block or attenuate selected wavelengths.
[0004] FIG. 1 illustrates a top view of a typical platform 102 A for a wavelength dispersive device in which a light redirecting element having optical power in the form of a spherical reflector 120 receives a beam of light from a front-end unit 122 . The spherical reflector 120 reflects the beam of light to a diffraction grating 124 , which disperses the beam of light into its constituent wavelength channels. The wavelength channels are again redirected by the spherical mirror 120 to a backend unit 126 .
[0005] In the case of a wavelength blocker (WB) or a dynamic gain equalizer (DGE) the front end unit 122 can include a single input/output port with a circulator, which separates incoming from outgoing signals, or one input port with one output port. Typically the front end unit 122 will include a polarization diversity unit for ensuring the beam (or sub-beams) of light has a single state of polarization. The backend unit 126 for a WB or a DGE is an array of liquid crystal cells, which independently rotate the state of polarization of the wavelength channels to either partially attenuate or completely block selected channels from passing back through the polarization diversity unit in the front end 122 .
[0006] In the case of a wavelength selective switch (WSS) the front end unit 122 includes (See FIG. 2 ) an array 132 of input/output fibers 132 A to 132 D, each of which may have a corresponding lens 134 A to 134 D, respectively, forming a lens array 134 . An angle to offset (or switching) lens 136 converts the lateral offset of the input fibers 132 A to 132 D into an angular offset at a point 138 , which is imaged by the spherical lens 120 onto the backend unit 126 . The lens array 134 can be removed depending on the relative positions of the switching lens 136 . The backend unit 126 in an WSS is typically a micro-electro-mechanical (MEMS) array of tilting mirrors which can be used to steer each of the demultiplexed beams to one of several positions corresponding to a desired output port. The angle introduced at the back end unit 126 is then transformed by the angle to offset lens 136 to a lateral offset corresponding to the desired input/output fiber 132 A to 132 D. Alternatively, a liquid crystal phased array (LC or LCoS, if incorporated on a silicon driver substrate) can be used to redirect the light.
[0007] In operation as an WSS, a multiplexed beam of light is launched into the front-end unit 122 and optionally passes through a polarization beam splitter 138 and a waveplate 140 A or 140 B (See FIG. 3 ) to provide two sub-beams of light having the same state of polarization. The two sub-beams of light are transmitted to the spherical reflector 120 and are reflected therefrom towards the diffraction grating 124 . The diffraction grating 124 separates each of the two sub-beams into a plurality of channel sub-beams of light having different central wavelengths. The plurality of channel sub-beams are transmitted to the spherical reflector 120 , which redirects them to the MEMS or LC phased array 126 , where they are incident thereon as spatially separated spots corresponding to individual spectral channels.
[0008] Each channel sub-beam can be reflected backwards along the same path or a different path, which extends into or out of the page in FIG. 1 to the array of fibers 132 , which would extend into the page. Alternatively, each channel sub-beam can be reflected backwards along the same path or a different path, which extends in the plane of the page of FIG. 1 . The sub-beams of light are transmitted, from the MEMS or LC phased array 126 , back to the spherical reflector 120 and are redirected to the diffraction grating 124 , where they are recombined and transmitted back to the spherical reflector 120 to be transmitted to a predetermined input/output port shown in FIG. 2 .
[0009] FIG. 4 illustrates a conventional in-plane or horizontally switching platform, in which an input beam with optical wavelength channels λ 1 and λ 2 is launched via input/output port 31 through switching lens 35 to concave mirror 40 . The input beam is redirected and collimated onto a diffraction grating 50 , which laterally disperses the optical wavelength channels, and directs them at the concave mirror 40 . Each optical wavelength channel is directed at and focused onto a different independently controllable micro-mirror, e.g. 61 and 62 , which make up a MEMs array 60 . The first optical wavelength channel λ 1 is reflected straight back and therefore exits the input/output port 31 , while the second optical wavelength channel λ 2 is reflected at a predetermined angle corresponding to the lateral position of a second input/output port 32 .
[0010] A transmission path correction element, i.e. wedge, 100 , with front and rear non-parallel faces 101 and 102 , respectively, is installed between the concave mirror 40 and the MEMS array 60 . The purpose of this correction element 100 is to modify the paths of the optical signals focused by the concave mirror 40 , so as to effectively rotate the best fit planar surface approximation FP into coplanar coincidence with the optical signal-receiving surface MP 65 of the MEMS array 60 . Non-limiting examples of a suitable (field-flattening) transmission path correction element that may be used for this purpose include a portion or segment of a cylindrical lens and an optical transmission wedge. With the curvilinear focal surface LP of the spherical mirror 40 being transformed into a focal plane FP, and with that plane FP being coincident with the MEMS array plane MP 65 , variation in loss, as minimized by the best fit linear approximation of the focal plane, will be effectively eliminated.
[0011] Unfortunately, each time a customer wishes to purchase a WB, a DGE, an MWS or any form of monitor therefor, they must purchase a separate dispersion platform, i.e. spherical lens and diffraction grating along with associated opto-mechanics and packaging. An object of the present invention is to overcome the shortcomings of the prior art by providing a multi-unit wavelength dispersive device, in which a plurality of independent front and backend units can utilize the same dispersion platform and share the same opto-mechanics and packaging.
SUMMARY OF THE INVENTION
[0012] Accordingly, the present invention relates to a multi-unit wavelength dispersing device comprising:
[0013] a first input port for launching a first multiplexed optical input beam including a plurality of wavelength channels;
[0014] one or more first output ports for outputting one or more of the plurality of wavelength channels from the first optical input beam;
[0015] a first switching lens having a first optical axis for converting a lateral displacement corresponding to a position of the first input port relative to the first optical axis into an angular displacement relative to the first optical axis, and for converting an angular displacement of an outgoing optical beam into a lateral displacement corresponding to a position of a selected one of the one or more first output ports;
[0016] a second input port for launching a second multiplexed optical input beam including a plurality of wavelength channels;
[0017] one or more second output ports for outputting one or more of the plurality of wavelength channels from the second optical input beam;
[0018] a second switching lens having a second optical axis for converting a lateral displacement corresponding to a position of the second input port relative to the second optical axis into an angular displacement relative to the second optical axis, and for converting an angular displacement of an outgoing optical beam into a lateral displacement corresponding to a position of a selected one of the one or more second output ports;
[0019] a main lensing element with optical power, having a central axis, for directing and focusing the first and second input optical beams;
[0020] a wavelength dispersing element for dispersing the first and second multiplexed optical input beams into constituent wavelength channels;
[0021] a first array of wavelength channel redirecting elements for independently directing one or more selected wavelength channels from the plurality of wavelength channels in the first optical input beam to a selected one of the one or more first output ports via the main lensing element and the wavelength dispersing element by providing an angular displacement to the one or more selected wavelength channels for conversion by the first switching lens into a lateral position corresponding to the selected first output port; and
[0022] a second array of wavelength channel redirecting elements for independently directing one or more selected wavelength channels from the plurality of wavelength channels in the second optical input beam to a selected one of the one or more second output ports via the main lensing element and the wavelength dispersing element by providing an angular displacement to the one or more selected wavelength channels for conversion by the second switching lens into a lateral position corresponding to the selected second output port.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] The invention will be described in greater detail with reference to the accompanying drawings which represent preferred embodiments thereof, wherein:
[0024] FIG. 1 is a schematic representation of a top view of a conventional wavelength dispersive device;
[0025] FIG. 2 is a schematic representation of a front end of the device of FIG. 1 ;
[0026] FIG. 3 is a schematic representation of a front end of the device of FIG. 1 ;
[0027] FIG. 4 is a schematic representation of a top view of another conventional wavelength dispersive switch;
[0028] FIG. 5 is a schematic representation of an isometric view of a wavelength dispersive device according to the present invention;
[0029] FIG. 6 is a schematic representation of a top view of a wavelength dispersive device according to the present invention
[0030] FIG. 7 is a schematic representation of a side view of a wavelength dispersive device according to an embodiment of the present invention;
[0031] FIG. 8 is a schematic representation of a side view of a back-end unit of a wavelength dispersive device according to the device of FIG. 7 ;
[0032] FIG. 9 is a schematic representation of an isometric view of a back-end unit of a wavelength dispersive device according to the device of FIG. 7 ;
[0033] FIG. 10 is a schematic representation of a side view of a wavelength dispersive device according to an embodiment of the present invention; and
[0034] FIG. 11 is a schematic representation of a side view of a back-end unit of a wavelength dispersive device according to the device of FIG. 10 .
DETAILED DESCRIPTION
[0035] A dual wavelength dispersive device 200 , illustrated in FIG. 5 , includes a single main lensing element having optical power, preferably in the form of a spherical, e.g. concave, reflector 201 , which receives two independent collimated beams of light from the front-end unit 202 , and which receives and reflects beams of light to and from a wavelength dispersing element, e.g. a diffraction grating 203 , and to and from a backend unit 204 . In this embodiment the front-end unit 202 , the diffraction grating 203 , and the backend unit 204 are each disposed along a single focal plane of the spherical reflector 201 ; however, other arrangements are within the scope of the invention, including using a convex lens (or a series of lenses) and placing the diffraction grating 203 on the opposite side thereof as the front and backend units 202 and 204 , respectively.
[0036] Preferably, the diffraction grating 203 , the spherical reflector 201 , and the backend unit 204 are each constructed of fused silica and mounted together with a beam folding mirror or prism 205 to a supporting plate 215 made of the same or made from a suitable low-expansion material, such as Invar®. The beam folding mirror or prism 205 is provided for space considerations, e.g. a MEMS chip with MEMS mirrors defining the backend unit 204 and their carrier are too large to fit next to the diffraction grating 203 . Accordingly, the beam folding mirror 205 redirects the beams so that the MEMS mirrors can be placed flat under the rest of the optics. Advantageously, the design of FIG. 5 provides stability with respect to small temperature fluctuations. Moreover, the design of FIG. 5 is defocus free, since the radius of curvature of the spherical reflector 201 changes in proportion to thermal expansion or contraction of any other linear dimensions. Advantageously, the spherical mirror 201 has substantially no chromatic aberrations. The wavelength dispersing element 203 can be a reflective or a transmissive diffraction grating, with ruled or replicated lines or holographically generated lines
[0037] Preferably, a transmission path correction element 220 is installed between the redirecting element, e.g. the concave mirror 201 , and the backend unit 204 , e.g. a MEMS array 243 , for reasons discussed hereinbefore with reference to FIG. 4 .
[0038] In the front-end unit 202 , the single switching lens, e.g. 136 or 35 , found in conventional wavelength dispersive devices, is replaced by first and second horizontal cylindrical lenses 231 a and 231 b and a single vertical cylindrical lens 232 to create an elliptical beam through the system, for reduced height of the optical system. The first and second horizontal cylindrical lenses 231 a and 231 b, are positioned between two fold mirrors 234 and 236 , and act as the switching lens, while creating the desired beam waist size in the vertical direction; the single vertical cylinder lens 232 creates the desired beam waist size in the horizontal direction, i.e. there are separate switching lenses 231 a and 231 b (horizontal cylinder lenses) for each beam at the front end unit 202 , while the “conditioning” lens 232 (vertical cylinder lens) is common to all the beams.
[0039] For the sake of simplicity, the fold mirrors 205 , 234 and 236 , and conditioning lens 232 will be eliminated from any further illustrations.
[0040] With reference to FIGS. 6 to 9 , the operation of the dual wavelength dispersion device 200 will be described with reference to simultaneously redirecting a pair of wavelength channels λ 1a and λ 2a from a first input optical beam including a plurality of wavelength channels λ 1a to λ 9a , and independently redirecting a pair wavelength channel λ 8b and λ 9b from a second input optical beam including a plurality of wavelength channels λ 1b to λ 9b . Since the number of supported wavelengths usually exceeds the number of output ports, each wavelength channel λ 1a and λ 2a can represent one or several wavelength channels. The front end unit 202 includes a first set of input/output ports 241 optically coupled to the first horizontal cylindrical lens 231 a, and a second set of input/output ports 242 optically coupled to the second horizontal cylindrical lens 231 b, but not optically coupled to the first horizontal cylindrical lens 231 a. Preferably, the first set of input/output ports 241 are positioned symmetrically on either side of the optical axis of the first horizontal cylindrical lens 231 a, while the second set of input/output ports 242 are positioned symmetrically on either side of the optical axis of the second horizontal cylindrical lens 231 b The second set of input/output ports 242 are independent of the first set of input/output ports 241 , i.e. light entering one of the first set of input/output ports 241 will not exit one of the second set of input/output ports 242 . Preferably, the first and second horizontal cylindrical lenses 231 a and 231 b are substantially equally spaced on opposite sides of the optical axis OA of the reflector 201 . Typically a multiplexed beam of light is launched into the front-end unit 202 and passes through a polarization beam splitter and a waveplate (See FIG. 3 ) to provide two sub-beams of light having the same state of polarization; however, for the sake of simplicity only a single input optical beam will be discussed hereinafter.
[0041] The first input optical beam including the plurality of wavelength channels λ 1a to λ 9a is launched via one of the input/output ports in the first set of input/output ports 241 and is redirected by the first horizontal cylindrical lens 231 a through a point 245 in the focal plane of the reflector 201 to become incident on the reflector 201 for a first time at point 1 a. The first input optical beam is reflected and collimated by the reflector 201 towards the diffraction grating 203 , whereby the first input optical beam is angularly dispersed into constituent wavelength channels, as each wavelength is reflected off of the diffraction grating 203 at a different angle (see FIG. 6 ). In the preferred embodiment illustrated in FIGS. 6 and 7 , the wavelengths are dispersed in a dispersion plane, which is in the plane of (or parallel to or at an acute angle to the plane of) FIG. 6 , but perpendicular to the plane of FIG. 7 , and perpendicular to the plane including the first and second sets of input/output ports 241 and 242 , respectively, although dispersing the wavelengths in the plane of FIG. 7 is also possible.
[0042] The dispersed wavelengths λ 1a to λ 9a are incident on the reflector 201 a second time at a series of points 2 a, and are then reflected and focused to a first array of channel wavelength redirecting elements 243 e.g. a MEMs array of mirrors or an LC phased array, in the backend 204 in a first dispersion plane. The first array of redirecting elements 243 includes a plurality of tilting mirrors or LC cells, one for each wavelength channel for independently redirecting each wavelength channel λ 1a to λ 9a to any one of the first set of input/output ports 241 . Preferably, all of the mirrors in the MEMs array 243 tilt about a single axis A 1 , which lies in the first dispersion plane (or parallel thereto), i.e. in or parallel to or at an acute angle to the plane of FIG. 6 and perpendicular to the plane of FIG. 7 , to enable the wavelength channels λ 1a to λ 9a to be redirected out at an acute angle to the first dispersion plane, i.e. out of the plane of FIG. 6 and in the plane of (or a plane parallel to the plane of) FIG. 7 . In the illustrated alignment, one or more of the wavelength channels, e.g. λ 1a and λ 2a , is redirected by the first MEMs array 243 relative to the remaining wavelength channels λ 3a to λ 9a , which travel back along the same path as the incoming signal hitting the reflector 201 at points 2 a, recombining at the diffraction grating 203 forming a first multiplexed output beam, hitting the reflector 202 at point 1 a, and exiting the same input/output port through which the input beam was launched. FIG. 8 illustrates the nine angles of reflection, i.e. nine angular positions, provided by the MEMs array 243 corresponding to the nine input ports in the first set of input/output ports 241 . More or less reflection angles, i.e. angular positions, are possible depending on the number of input/output ports. The redirected wavelength channels λ 1a and λ 2a are directed towards and reflector 201 and are incident thereon for a third time at point 3 a, after which the wavelength channels λ 1a and λ 2a are directed to the diffraction grating 203 at a separate location than before for recombination into a second multiplexed output beam. Subsequently, the second multiplexed output beam, comprised of the wavelength channels λ 1a and λ 2a , is reflected by the reflector 201 to the front end 202 . The second multiplexed output beam, along with all incoming and outgoing beams, passes through point 245 in the focal plane of the reflector 201 at an angle to the optical axis of the first horizontal cylindrical lens 231 a, corresponding to the reflection angle provided by the MEMs array 243 , which corresponds to the desired input/output port. The first horizontal cylindrical lens 231 a converts the angle into a lateral displacement corresponding to the lateral position of the desired input/output port in the set of input/output ports 241 .
[0043] Simultaneously, a second input optical beam including a plurality of wavelength channels λ 1b to λ 9b is launched via one of the input/output ports in the second set of input/output ports 242 and redirected by the second horizontal cylindrical lens 231 b through a point 246 in the focal plane of the reflector 201 to become incident on the reflector 201 for a first time at point 1 b. The second input optical beam is reflected by the reflector 201 towards the diffraction grating 203 , whereby the second input optical beam is angularly dispersed into constituent wavelength channels, as each wavelength is reflected off of the diffraction grating 203 at a different angle (see FIG. 6 ). In the preferred embodiment illustrated in FIGS. 6 and 7 , the wavelengths are dispersed in a dispersion plane, which is in the plane of (or parallel to or at an acute to angle the plane of) FIG. 6 , but perpendicular to the plane of FIG. 7 , and perpendicular to the plane including the first and second sets of input/output ports 241 and 242 , respectively, although dispersing the wavelengths in the plane of FIG. 7 (or a plane parallel to the plane of FIG. 7 ) is also possible.
[0044] The dispersed wavelengths λ 1b to λ 9b are incident on the reflector 201 a second time at a series of points 2 b, and are then reflected to a second array of channel wavelength redirecting elements e.g. a MEMs array 244 , in the backend 204 in a second dispersion plane preferably parallel to the first dispersion plane. The MEMs array 244 includes a plurality of tilting mirrors, one for each wavelength channel for independently redirecting each wavelength channel λ 1b to λ 9b to any one of the second set of input/output ports 242 , i.e. only the second set of input/output ports 242 , none of the first set of input/output ports 241 . Preferably, the mirrors in the second MEMs array 244 tilt about an axis A 2 , which lies in the second dispersion plane, i.e. in or parallel to the plane of FIG. 6 and perpendicular to the plane of FIG. 7 , to enable the wavelength channels λ 1b to λ 9b to be redirected out at an acute angle to the second dispersion plane, i.e. out of the plane of (or a plane parallel to the plane) FIG. 6 and in the plane of (or a plane parallel to the plane of) FIG. 7 . In the illustrated alignment, one or more of the wavelength channels, e.g. λ 1b and λ 2b , are redirected by the second MEMs array 244 relative to the remaining wavelength channels λ 3b to λ 9b , which travel back along the same path as the second input beam hitting the reflector 201 at points 2 b, recombining at the diffraction grating 203 forming a third multiplexed output beam, hitting the reflector 202 at point 1 b, and exiting the same input/output port through which the second input beam was launched. FIG. 8 illustrates the nine angles of reflection, i.e. nine angular positions, provided by the MEMs array 244 corresponding to the nine input ports in the second set of input/output ports 242 . More or less reflection angles, i.e. angular positions, are possible depending on the number of input/output ports. The redirected wavelength channels λ 1b and λ 2b are directed towards and reflector 201 and is incident thereon for a third time at point 3 b, after which the wavelength channels λ 1b and λ 2b are directed to the diffraction grating 203 at a separate location than before for recombination into a fourth multiplexed output beam. Subsequently, the fourth multiplexed output beam, comprised of the wavelength channels λ 1b and λ 2b , is reflected by the reflector 201 to the front end 202 . The fourth multiplexed output beam, along with all incoming and outgoing beams, passes through point 246 in the focal plane of the reflector 201 at an angle to the optical axis of the second horizontal cylindrical lens 231 b, corresponding to the reflection angle provided by the second MEMs array 244 , which corresponds to the desired input/output port. The second horizontal cylindrical lens 231 b converts the angle into a lateral displacement corresponding to the lateral position of the desired input/output port in the second set of input/output ports 242 .
[0045] In the illustrated example, the first and second MEMs arrays 243 and 244 are separated by the same amount as the first and second horizontal cylindrical lenses are separated, e.g. by about 1.5 mm, and the first and second sets of input/output ports are separated by approximately 1.5 mm. The first and second MEMs arrays 243 and 244 are preferably fabricated parallel to each other on a single substrate 250 , which would enable precision alignment between the two arrays, thus eliminating the need for separate alignment of the two arrays 243 and 244 . A dual row MEMs array is less expensive than two single row MEMs arrays, and only marginally more expensive than a single row MEMs array. Similarly, the first and second horizontal cylindrical lenses 231 a and 231 b can be fabricated as a single molded optical element, thereby enabling precision alignment therebetween, and eliminating separate alignment of the individual lenses.
[0046] Alternative arrangements could have any combination of wavelengths λ 1a to λ 9a being output any combination of input/output ports in the first set of input/output ports 241 , and any combination of wavelengths λ 1b to λ 9b being output any combination of input/output ports in the second set of input/output ports 242 . Moreover, the first and second MEMs arrays 243 and 244 can be designed to switch the individual wavelength channels within the same dispersion plane, while the first and second set of input ports 241 and 242 can also be aligned in the same dispersion plane.
[0047] Furthermore, the first and second MEMs array 243 and 244 can be replaced by other optical switching elements, e.g. liquid crystal on silicon (LCoS) phased arrays, such as those disclosed in United States Patent Publication No. 2006/0067611 published Mar. 30, 2006 to Frisken et al, or an array of polarization rotators, e.g. liquid crystal cells, for independently rotating the polarization of individual wavelength channels λ 1b to λ 9b , whereby a portion, i.e. for a DGE, or the entire wavelength channel, i.e. for a WB or WSS, will be blocked or switched by a beam splitting element provided in the backend unit 204 or in the front end unit 202 , e.g. as part of the polarization diversity element. For a DGE or a WB arrangement, all of the wavelength channels λ 1b to λ 9b are recombined by the grating 203 into a single multiplexed output beam, and are returned to the same input/output port, whereby a circulator directs the single multiplexed output beam to an output port. Alternatively, all of the wavelength channels λ 1b to λ 9b can be redirected by the polarization rotating device at an angle to the incoming beam and recombined by the grating 203 into a single multiplexed output beam, which is output a different input/output port in the front end unit 202 .
[0048] With reference to FIGS. 10 and 11 , a multi-unit WSS device 300 preferably includes a single main lensing element having optical power in the form of a spherical, i.e. concave, reflector 301 , which receives three independent collimated beams of light from the front-end unit 302 , and which receives and reflects beams of light to and from a diffraction grating 303 , and to and from a backend unit 304 . In this embodiment the front-end unit 302 , the diffraction grating 303 , and the backend unit 304 are each disposed along a single focal plane of the spherical reflector 301 ; however, other arrangements are within the scope of the invention, including using a convex lens and placing the diffraction grating 303 on the opposite side thereof as the front and backend units 302 and 304 , respectively.
[0049] A transmission path correction element can be installed between the redirecting element, e.g. the concave mirror 301 , and the backend unit 304 , e.g. a MEMS array 343 , for reasons discussed hereinbefore with reference to FIG. 4 .
[0050] In the front-end unit 302 , the single switching lens, e.g. 136 or 35 , found in conventional wavelength dispersive devices, is replaced by first, second and third horizontal cylindrical lenses 331 a, 331 b and 331 c and a single vertical cylindrical lens 332 to create an elliptical beam through the system, for reduced height of the optical system. The first, second and third horizontal cylindrical lenses 331 a, 331 b and 331 c, can be positioned between two fold mirrors (not shown), and act as the switching lens, while creating the desired beam waist size in the vertical direction; the single vertical cylinder lens 332 creates the desired beam waist size in the horizontal direction, i.e. there are separate switching lenses 331 a, 331 b and 331 c (horizontal cylinder lenses) for each beam at the front end unit 302 , while the “conditioning” lens 332 (vertical cylinder lens) is common to all the beams. For the sake of simplicity, the fold mirrors and conditioning lens have been eliminated from the illustrations.
[0051] The front end unit 302 includes a first set of input/output ports 341 optically coupled to the first horizontal cylindrical lens 331 a, and a second set of input/output ports 342 optically coupled to the second horizontal cylindrical lens 331 b, but not optically coupled to the first horizontal cylindrical lens 331 a, and a third set of input/output ports 343 optically coupled to the third horizontal lens 331 c, but not the first and second horizontal cylindrical lenses 331 a and 331 b. Preferably, the first set of input/output ports 341 are positioned symmetrically on either side of the optical axis of the first horizontal cylindrical lens 331 a, while the second set of input/output ports 342 are positioned symmetrically on either side of the optical axis of the second horizontal cylindrical lens 331 b, and the third set of input/output ports 343 are positioned symmetrically on either side of the optical axis of the second horizontal cylindrical lens 331 c. The second and third sets of input/output ports 342 and 343 are independent of each other and of the first set of input/output ports 341 , i.e. light entering one of the first set of input/output ports 341 will not exit one of the second set of input/output ports 342 . Preferably, the optical axis of the first horizontal cylindrical lens 331 a is aligned with the central axis of the reflector 301 , while the second and third horizontal cylindrical lenses 331 b and 331 c are substantially equally spaced on opposite sides of the optical axis OA of the reflector 301 . Typically a multiplexed beam of light is launched into the front-end unit 302 and passes through a polarization beam splitter and a waveplate (See FIG. 3 ) to provide two sub-beams of light having the same state of polarization; however, for the sake of simplicity only a single input optical beam will be discussed hereinafter.
[0052] A first array of MEMs mirrors 344 in the back end unit 304 is used to independently direct one or more selected wavelength channels, e.g. λ 1c , from the original set of wavelength channels, e.g. λ 1c to λ 11c , to selected output ports in the first array of output ports 341 , as hereinbefore described with reference to FIG. 7 .
[0053] When switching lenses are placed above and/or below the optical axis OA of the spherical reflector 301 , the available numerical aperture on the spherical reflector 301 is reduced, whereby fewer ports can be accommodated. In the multi-unit MWS 300 the first horizontal cylindrical lens 331 a is positioned on-axis with the reflector 301 , whereby eleven ports can be accommodated in the first set of input/output ports 341 ; however, the farther the second and third cylindrical lenses 331 b and 331 c are from the optical axis OA of the spherical reflector 301 , the fewer the number of ports that can be accommodated in the second and third sets of input/output ports 342 and 343 . Accordingly, the second and third sets of input/output ports 342 and 343 can be used for alternative functions, e.g. DGE, WB or reduced port-count WSS (as hereinbefore described) and channel monitoring. In the case in which the second or third set of ports is used for a reduced port count WSS capable of functioning in an Nx1 configuration with N input ports for accepting multiplexed inputs and one common output, external passive combiners can be added to the N input ports to further increase the total input port count.
[0054] For channel monitoring, a plurality of wavelength channels, e.g. λ 1m to λ 11m , are launched via a first input/output port 342 ′, and one wavelength channel, λ nm , at a time is redirected by an array of MEMs mirrors 345 to a second input/output port 342 ″, which is optically coupled to a photodetector PD for measuring the output optical power of the selected wavelength channel as each wavelength channel is selected sequentially. The remaining wavelength channels are redirected to a third input/output port or back to the first input/output port 342 ′, which includes a circulator for separating the incoming signals from the outgoing signals and directing the outgoing signals to a separate output port.
[0055] The third set of input/output ports 343 can also be used as an WSS, but with a limited number of input/output ports, e.g. four. If the number of addressable ports in the third set of input/output ports 343 is fewer than half of the number of addressable ports in the first set of input/output ports 341 , then the third array of MEMs mirrors 346 can be fabricated in the same process and on the same substrate 350 as the first array 344 , but the third array can be processed to tilt with a limited angular range, i.e. only one direction from the horizontal, e.g. one end of each mirror will only have to tilt clockwise between a horizontal position and below horizontal without having to rotate counterclockwise above the horizontal position. Accordingly, the number of electrodes required per mirror can be reduced, e.g. by at least one half, along with the number of electrical connections thereto, since electrodes will not be required under both sides of the mirrors.
[0056] Similar to FIG. 8 , FIG. 11 illustrates the different output angles provided by the first, second and third arrays of MEMs mirrors 344 , 345 and 346 , respectively. The mirrors in the first MEMs array 344 have eleven different angular positions corresponding to the eleven different input/output ports in the first array 341 of input/output ports. The mirrors in the second MEMs array 345 have only two different positions for either directing the wavelength channel back to the input port 342 ′ or to the output port 342 ″ for sequential power monitoring. The mirrors in the third array 346 have four different positions corresponding to the limited number of ports provided in the third array of input/output ports 343 .
[0057] In use the output ports of one of the arrays of input/output ports may be optically coupled to the input ports of the other arrays of input/output ports to provide cascaded functionality, e.g. one of the signals output the WWS formed by the first array 341 and 344 can be output to the channel monitor formed by the third arrays 343 and 346 and/or the signal output the channel monitor (third arrays 343 and 346 ) can be then output to an attenuator/WB formed second arrays 342 and 345 . Alternatively, all of the channels can be sent to the channel monitor (third arrays 343 and 346 ) initially and then passed to the WSS (first array 341 and 344 ) and/or to the attenuator/WB (second arrays 342 and 345 ). | The multi-unit wavelength switch enables multiple independent wavelength switching of a plurality of incoming multiplexed optical beams simultaneously on the same optical platform. The different units can have similar functionality or provide disparate functionality, e.g. any one or more of switching, dynamic gain equalization, wavelength blocking, and power monitoring. | 6 |
TECHNICAL FIELD
The present invention relates to systems for processing sewage; more particularly, to such systems for handling biologically digestible materials in sewage; and most particularly to methods and apparatus for separating biologically-digestible materials from an influent sewage stream.
BACKGROUND OF THE INVENTION
The primary historical objective of waste water treatment operations has been to neutralize and otherwise render sewage effluence in compliance with regulatory limits based on environmental and health standards. An important and growing objective of modern waste water treatments is the generation of energy from biologically-digestible organic materials present in the waste water. To achieve this objective, during the treatment of waste water influent streams containing biologically-digestible materials, as part of selectively classifying and separating grits, solids, hair and fibers, particulates, and solvated materials, it is particularly desirable to separate the digestible materials in the influent stream from non-digestible materials such that digestion of the digestible materials can be optimized. For systems that produce sludge in processes downstream from primary clarification (i.e., secondary sludge), it is desirable to extract the remaining biologically-digestible materials present in that sludge. Optimization can include increasing and capturing the bio-gas producing materials; production of energy bearing bio-gasses such as methane, produced by the decomposition of the digestible materials; reducing the frequency with which digesters used to digest the digestible materials need to be taken off line and cleaned; automation of the process for separating the digestible materials in the influent stream for digestion to reduce operating costs; reducing energy consumption-related operating costs; reducing the particle size of organic materials to allow rapid biodegradation and to capture organics prior to conversion to carbon-dioxide and biomass; and reducing the capital costs to build a treatment facility to separate and digest biologically-digestible materials in an influent stream.
In the prior art, the separation of grit from waste water influent is a long standing problem. Grit adversely impacts equipment reliability and lifespan, and increases operating costs of downstream treatment processes. Consequently, grit separators traditionally are used to remove grit from the influent stream as early in the treatment sequence as possible, preferably prior to primary clarification, or in cases where no primary clarification exists, then prior to secondary treatment. In practice, these devices often perform poorly because they are designed for a specific flow range which often is based on peak flows based on projected increases in population or a specific maximum flow based on storm events or future expansion of flows from new industries, etc. The projected flow range frequently is not reached for a number of reasons, such as unanticipated changes in population; changes in economic conditions of a region causing industries to leave or never develop; increased inflow and infiltration (“I and I”) of water into the treatment system from deteriorating collection systems; and the increase in storm intensities.
In many treatment plants, in an attempt to provide flow equalization at the head of the plant, variable frequency drives have been added to control the pumps delivering influent to the treatment plants from wet wells used as buffers. The variable frequency drives enable operation of the pumps over a range of pump speeds rather than a single speed with the only control option being to turn them off and on. In practice, these variable frequency drives create large fluctuations in influent velocity that can hinder the performance of the highly velocity-sensitive hydrocyclone grit separators. Due to their poor performance, these velocity sensitive grit separators often fail and/or are left in disrepair, requiring grit to be removed from the influent stream as a component of the sludge formed during the primary-treatment process. Typically, the grit slowly fills the secondary treatment process tanks, contributing to reduced energy content of the primary sludge, increasing the frequency with which digesters and secondary process tanks must be cleaned, and causing wear and tear on the plant equipment.
Current typical waste water plants capture only thirty to thirty-five percent of the biologically-digestible materials during primary clarification. The remainder of the biologically-digestible materials are typically digested during secondary treatment in an activated sludge process that permits the greenhouse gas (CO 2 ) to escape into the atmosphere.
SUMMARY OF THE INVENTION
Briefly described, a system in accordance with the present application comprises a method and apparatus for separating biologically digestible materials from an influent sewage stream.
In one aspect of the present application, a primary clarification tank is used to capture sixty percent or more of the total solids from an influent stream.
In another aspect of the present application, a sludge classifying press (SCP) is used to isolate and concentrate biologically-digestible materials from sludge formed in a primary clarification tank, releasing valuable organics, such as are found in corn kernels, by fracturing the protective casings.
In another aspect of the present application, grit is captured in a chamber within the primary clarification tank and isolated from the bulk of the sludge-containing biologically-degradable materials.
In another aspect of the present application, a grit trap or hydrocyclone is used to remove grit from the sludge prior to classifying the sludge with the SCP.
In another aspect of the present application, the sludge is thickened after classification and prior to digestion.
In another aspect of the present application, one or more elements of the process for separating and digesting the biologically-digestible materials in an influent stream is automated.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will now be described, by way of example, with reference to the accompanying drawings, in which:
FIG. 1 is a schematic drawing of an embodiment of a water treatment plant in accordance with the present application;
FIG. 2 is a schematic drawing and elevational side view of an Influent Feed System (IFS) used in the embodiment shown in FIG. 1 ;
FIG. 3 is a detailed plan view of one IFS shown in FIG. 1 ;
FIG. 4 is a schematic drawing of a prior art primary treatment system suitable for use as a first stage in the present application to collect suspended and solvated BOD;
FIG. 5 is a schematic drawing and elevational end view of one embodiment of a clarification tank and IFS in fluid communication with apparatus to treat grit and sludge settled in the clarification tank and IFS in accordance with the present application;
FIG. 6 is a schematic elevational drawing of a grit separator in accordance with the present application;
FIG. 7 is a schematic drawing and plan view of an alternative embodiment of a clarification tank and IFS in fluid communication with apparatus to treat grit and sludge settled in the clarification tank and IFS in accordance with the present application;
FIG. 8 is a schematic drawing and plan view of another alternative embodiment of a clarification tank and IFS in fluid communication with apparatus to treat grit and sludge settled in the clarification tank and IFS in accordance with the present application;
FIG. 9 is a schematic drawing and plan view of another alternative embodiment of a clarification tank and IFS in fluid communication with apparatus to treat grit and sludge settled in the clarification tank and IFS in accordance with the present application;
FIG. 10 is an alternative embodiment of an IFS with separate discharge pipes for removing materials from the IFS troughs and grit box;
FIG. 11 is a schematic drawing and side elevational view of an IFS arranged to discharge grit and sludge in accordance with the present application; and
FIG. 12 is a schematic drawing and plan view of an adapative system for treatment of sludge and grit in accordance with the present application.
Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate currently preferred embodiments of the invention, and such exemplifications are not to be construed as limiting the scope of the invention in any manner.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
U.S. Pat. No. 7,972,505, PRIMARY EQUALIZATION SETTLING TANK, to Wright; U.S. Pat. No. 8,225,942 to Wright, SELF-CLEANING INFLUENT FEED SYSTEM FOR A WASTEWATER TREATMENT PLANT; U.S. Pat. No. 8,398,864 SCREENED DECANTER ASSEMBLY FOR A SETTLING TANK to Wright; co-pending U.S. patent application Ser. No. 14/142,197 METHOD AND APPARATUS FOR A VERTICAL LIFT DECANTER SYSTEM IN A WATER TREATMENT SYSTEM by Wright; co-pending U.S. patent application Ser. No. 14/142,099 FLOATABLES AND SCUM REMOVAL APPARATUS FOR A WASTE WATER TREATMENT SYSTEM by Wright, and co-pending U.S. patent application Ser. No. 14/325,421 IFS AND GRIT BOX FOR WATER CLARIFICATION SYSTEMS by Wright (the '421 application), all of which are incorporated by reference in their entirety for all purposes, disclose systems and processes for primary clarification that remove substantially all grit, solids, and particulates larger than 50 microns during primary clarification.
Separation of Biologically Digestible Materials from the Influent Stream
FIG. 1 shows a block diagram of one exemplary embodiment of a clarification system 1 configured to separate biologically-digestible materials from an influent stream. In one embodiment, the influent enters the clarification system 1 via pipes 11 where it is stored in wet well 12 . A settling tank 30 is in fluid communication with eight IFS's, 100 - 107 . Pump 13 pumps influent from wet well 12 to IFS's 100 - 107 at a substantially constant flow rate via piping 14 , 15 and 15 ′. In one embodiment, pump 13 operates under the control of a supervisory control and data acquisition system (SCADA) 900 in communication with pump 13 via communication channel 901 . In one embodiment, the SCADA 900 turns pump 13 in response to an indication of wet well 12 fluid level reaching an upper limit, the indication provided by sensor 18 in communication with SCADA 900 via communication channel 907 . In one embodiment, SCADA 900 turns pump 13 off in response to an indication of wet well 12 fluid level reaching a lower limit, the indication provided by sensor 19 in communication with SCADA 900 via communication channel 908 . In an alternative embodiment, SCADA 900 turns pump 13 off after a pre-determined period of time. In an alternate embodiment, SCADA 900 turns pump 13 off after a predetermined volume of fluid has been pumped as indicated by measuring the flow via signals provided by flow meter 25 in communication with SCADA 900 via communication channel 909 . Flow meters and sensors to measure fluid level are well known in the art.
As is well known in the art, pipes 14 , 15 and 15 ′ are configured to deliver substantially the same flow rate of influent to each IFS 100 - 107 . Flow balancing valves and/or flow splitting may be used. The influent enters the IFS's 100 - 107 where grits, solids, and optionally solvated materials, are selectively classified and separated from the influent via settling and optionally flocculation. Materials settled in the IFS's 100 - 107 are removed via discharge pipes 570 - 577 as described in more detail with reference to FIG. 5 . The influent traverses IFS's 100 - 107 to enter clarification settling tank 30 . As described in the '505 and '864 patents and '197 application, solids remaining in the influent traversing to the clarification settling tank 30 are further classified and separated from the influent via settling. Upon completion of the separation of the solids from the influent, the influent is discharged from the settling tank 30 using screen box assemblies (SBX's) 50 - 54 as described in the '197 application.
In the embodiment of FIG. 1 , flocculents are optionally added to the influent stream by flocculent delivery systems 40 , 41 . The use of flocculents, for the removal of solids and solvated materials in the treatment of waste water and designs to add flocculents to an influent waste water stream, is well known in the art.
FIG. 2 shows a side view of an exemplary IFS 100 with IFS troughs and grit box 500 and FIG. 3 shows a top view of the IFS of FIG. 2 , as further described and disclosed in the '421 application. As described in more detail in the '421 application, a mixing zone 504 is created within a grit box 500 at the location where deposition of the floc is desired. With reference to FIG. 2 and FIG. 3 , IFS 100 is configured with a grit box 500 and two IFS troughs 201 , 202 having trough walls 207 , 208 . IFS troughs 201 , 202 are in fluid communication with the grit box 500 . Influent is delivered to IFS 100 via pipe 501 and is split into two streams which enter grit box 500 via pipes 502 , 503 . The streams exit opposing pipes 502 , 503 and collide under pressure to create turbulent mixing zone 504 . A deflector plate 505 is positioned above mixing zone 504 to confine the volume of the mixing zone and return the upward velocities of the streams existing pipes 502 , 503 back into mixing zone 504 . Grit, dense solids, and flocs are deposited in grit box hopper 506 .
To limit disturbance of solids settling in the lower portion of IFS troughs 201 , 202 in proximity to the grit box 500 , the length of pipes 502 , 503 is arranged to position mixing zone 504 below the lowest portion of IFS troughs 201 , 202 in proximity to and in fluid communication with grit box 500 . Mixing zone 504 and grit box hopper 506 are positioned below the lowest portion 150 , 150 ′ of IFS troughs 201 , 202 in proximity to and in fluid communication with grit box 500 . Solids with a lower settling rate than the designed influent rise velocity in the grit box hopper 506 move into IFS troughs 201 , 202 . Additionally, prior to entering IFS troughs 201 , 202 , solids moving upward under the influence of the rising influent undergo a 90 degree change in direction, turning from vertical to horizontal thus losing inertia and lessening the fluid forces on the suspended grits, solids, and flocs. In one embodiment, as explained in more detail below, grits settle preferentially in grit box 500 .
Materials that settle in grit box 500 and clarification, tank 30 may be removed as part of periodic scouring of grit box 500 and clarification tank 30 or as part of the ongoing operation of clarification system 1 to selectively classify and separate grits, solids, particulates, and solvated materials from an influent stream.
Other methods may be used to separate and capture large quantities of biologically digestible material from an influent stream. By way of example and not limitation, with reference to FIG. 4 , large quantities of solids, suspended materials, and solvated materials can be rapidly settled from an influent stream by a prior art system such as CLARI-FLOCCULATOR packaged sewage treatment 1100 for primary treatment manufactured by Waterneer, a company with offices in Lidkoping Sweden. In the Waterneer primary treatment system, inlet feed pump 1102 is in fluid communication with influent stream 1101 and mixing chamber 1103 . Flocculent source 1106 is in fluid communication with mixing chamber 1103 . Mixing chamber 1103 is in fluid communication with turbulence redirection apparatus 1104 which is in fluid communication with sedimentation chamber 1105 . Sedimentation chamber 1105 further comprises a sludge discharge pipe 1111 , a sensor 1108 in communication with programmable controller 1107 , and valve 1109 under control of and in communication with programmable controller 1107 . Valve 1109 is positioned in sludge discharge pipe to control fluid communication of materials from sedimentation chamber 1109 through sludge discharge pipe 1111 .
In the Waterneer primary treatment system, inlet feed pump 1102 pumps water from influent stream 1101 into a mixing chamber 1103 where it is mixed with flocculents added to the influent stream by flocculent source 1106 . The influent and flocculent mix is delivered to turbulence redirection apparatus 1104 to slow the velocity of the fluid after which it is delivered to sedimentation chamber 1105 where flocs, grits and other materials settle. Effluent 1110 , free of the settled materials, is evacuated from primary treatment system 1100 . Programmable controller 1106 opens and closes valve 1109 responsive to signals from sensor 1108 indicating that the thickness of the sludge settled in sedimentation chamber 1105 has exceeded a predetermined threshold. Sludge from sedimentation chamber 1105 is evacuated via discharge pipe 1111 .
Treatment of Materials Separated from the Influent Stream to Concentrate Biologically-Digestible Materials
With reference to FIGS. 2 and 5 , grit box 500 of IFS 100 is in fluid communication with discharge pipe 570 . Fluid communication via discharge pipe 570 is controlled by valve 580 . Valve 580 may be a manually-operated valve. In an alternate embodiment, valve 580 is electronically controlled by a supervisory control and data acquisition SCADA system 900 which provides a signal via communication channel 919 to open and close valve 580 . SCADA systems and electronically controlled valves are well known in the art.
With reference to FIG. 5 in one embodiment, IFS 100 , 104 discharge pipes 570 , 574 and clarification tank 30 discharge pipe 70 are in fluid communication with sludge and grit intake pipe 20 which is in fluid communication with sludge pump 50 . Sludge pump 50 is in fluid communication with grit separator 51 via pipe 20 a . Grit separator 51 is in fluid communication with sludge classification press 52 via pipe 20 b. Sludge classification press 52 is in fluid communication with optional sludge thickener 53 via pipe 20 c . Sludge thickener 53 is in fluid communication with pipe 20 d . Optionally, a flocculent source 55 a is arranged to communicate flocculents to sludge prior to treatment by sludge classification press 52 . Optionally, a flocculent source 55 b is arranged to communicate flocculents to the sludge discharged by sludge classification press 52 . In one embodiment, sludge pump 50 is in communication with and controlled by SCADA 900 via communication channel 926 . In one embodiment, classification press 52 is in communication with and controlled by SCADA 900 via communication channel 927 . In one embodiment, flocculent sources 55 a , 55 b are in communication with and controlled by SCADA 900 via communication channels 929 a , 929 b . In one embodiment, sludge thickener 53 is in communication with and controlled by SCADA 900 via communication channel 928 .
In one embodiment, one or more optional flowmeters are incorporated in the system: flow meter 5701 to measure the flow in discharge pipe 570 ; flow meter 5741 to measure the flow in discharge pipe 574 ; flow meter 7001 to measure the flow in discharge pipe 70 ; flow meter 2001 to measure the flow in pipe 20 a; flow meter 2003 to measure the flow in discharge pipe 20 b; flow meter 2005 to measure the flow in pipe 20 c; and flow meter 2007 to measure the flow in pipe 20 d.
In one embodiment, flow meter 5701 is in communication with SCADA 900 via communication channel 917 . In one embodiment, flow meter 5741 is in communication with SCADA 900 via communication channel 920 . In one embodiment flow meter 7001 is in communication with SCADA 900 via communication channel 923 . In one embodiment, flow meter 2001 is in communication with SCADA 900 via communication channel 936 . In one embodiment, flow meter 2003 is in communication with SCADA 900 via communication channel 938 . In one embodiment, flow meter 2005 is in communication with SCADA 900 via communication channel 940 . In one embodiment, flow meter 2007 is in communication with SCADA 900 via communication channel 942 .
In one embodiment, one or more optional sensors are incorporated in the system: sensor 5702 to measure the characteristics of materials in discharge pipe 570 ; sensor 5742 to measure the characteristics of materials in discharge pipe 574 ; sensor 7002 to measure the characteristics of materials in discharge pipe 70 ; sensor 2002 to measure the characteristics of materials in discharge pipe 20 a; sensor 2004 to measure the characteristics of materials in discharge pipe 20 b; sensor 2006 to measure the characteristics of materials in discharge pipe 20 c; and, sensor 2008 to measure the characteristics of materials in discharge pipe 20 d . The optional sensors are in communication with SCADA 900 : sensor 5702 via communication channel 918 ; sensor 5742 via communication channel 921 ; sensor 7002 via communication channel 924 ; sensor 2002 via communication channel 937 ; sensor 2004 via communication channel 939 ; sensor 2006 via communication channel 941 ; and sensor 2008 via communication channel 943 .
Sensors 5702 5742 , 7002 , 2004 , 2006 , and 2008 may be a UVAS sensor, turbidity sensor, pH sensor, or any other type of sensor consistent with measuring the physical and/or chemical characteristics of sludge and grits undergoing treatment.
With reference to FIG. 5 , sludge 1000 settled in grit box 500 of IFS 100 can be removed via discharge pipe 70 . With reference to the exemplary embodiment of FIG. 2 , in one embodiment valve 580 is opened and fluid is pumped or gravity fed through pipes 410 , 415 to scour the IFS troughs and grit box. In an alternative method for evacuating and scouring the IFS, valve 580 is opened and IFS troughs 201 , 202 are scoured with liquid to evacuate solids from the entirety of the IFS. In one embodiment, as part of the ongoing operation of the clarification system 1 of FIG. 1 , to selectively classify and separate grits, solids, particulates, and solvated materials from an influent stream, valve 580 is opened to remove the settled materials without concurrent scouring of the IFS.
With reference to FIG. 5 , sludge 1000 settled in grit box 500 may have viscosity low enough to flow from the grit box under the influence of gravity. The solids content of the sludge is dependent on the type of solids, the depth of the tank, the methodology of extraction, and how long the sludge is resident in the tank prior to extraction. A representative range for the solids content of materials 1010 is from less than one-tenth of a percent to five percent or more. The head pressure from the influent in IFS 100 may be used to assist in moving sludge 1000 in grit box 500 through discharge pipe 570 . In one embodiment, sludge pump 50 is used to assist in the evacuation of materials 1000 settled in grit box 500 . In one embodiment, sludge pump 50 is electronically controlled by a supervisory control and data acquisition system SCADA 900 which provides a signal via communication channel 926 to start and stop pumping.
With reference to FIG. 5 , sludge 1010 settled in clarification tank 30 can be removed via discharge pipe 70 in liquid communication with the clarification tank 30 . Fluid communication via discharge pipe 70 is controlled by valve 80 . Sludge 1010 settled in clarification tank 30 can be removed by scouring and cleaning with a fluid as described for example in the '864 patent. In one embodiment, as part of the ongoing operation of clarification system 1 of FIG. 1 , to selectively classify and separate grits, solids, particulates, and solvated materials from an influent stream, valve 80 is opened to remove the settled materials.
Sludge 1010 , settled in clarification tank 30 may have viscosity low enough to flow from clarification tank 30 under the influence of gravity. The solids content of the sludge is dependent on the type of solids, the depth of the tank, the methodology of extraction, and how long the sludge is resident in the tank prior to extraction. A representative range for the solids content of materials 1010 is from less than one-tenth of a percent to five percent or more. The head pressure from the influent in clarification tank 30 may be used to assist in moving sludge 1010 in the clarification tank 30 through discharge pipe 70 . In one embodiment, a sludge pump 50 is used to assist in the evacuation of sludge 1010 settled in clarification tank 30 .
Sludge from IFS 100 , 104 and clarification tank 30 enters grit separator 51 which separates and removes coarse, dense solids, referred to herein as “grit” or “grits”, that are not biologically digestible from the sludge. Grit separator 51 may be a gravity separator as shown with reference to FIG. 6 or a hydro-cyclone as is well known in the art. The removal of grits from the sludge removed from clarification tank 30 and IFS' 100 - 107 rather than from the influent stream prior to primary clarification provides for improved operation of the grit separator and overall plant reliability.
With reference to FIG. 6 , there is shown one embodiment of a grit separator 51 that is a gravity separator 1200 in accordance with the current invention. Gravity separator 1200 has an influent pipe 1201 in fluid communication with a gravity separation chamber 1202 . Gravity separation chamber 1202 is in fluid communication with grit discharge pipe 1203 and sludge discharge pipe 1204 . Valve 1205 is positioned on grit discharge pipe 1203 and controls fluid communication through pipe 1203 . Influent pipe 1201 is arranged to have dimensions perpendicular to the flow of influent sludge substantially larger than the dimensions perpendicular to the flow of influent sludge of pipes providing a source of sludge to be treated for removal of grit. Influent pipe 1201 is arranged to provide a downward direction to the flow of fluids and materials as they enter gravity separation chamber 1202 giving dense solids inertia downward to gently agitate settled solids and to re-suspend any low density organic materials. The bottom of gravity separation chamber 1202 is designed to slope down to grit discharge pipe 1203 to facilitate discharge of grit under the influence of gravity.
In operation, sludge enters gravity separator 1200 from a source such as clarification tank 30 of FIG. 5 via pipe 20 a as shown with respect to FIG. 5 . The substantially larger dimensions of influent pipe 1201 relative to source pipe 20 a in the direction perpendicular to the direction of sludge flow results in a rapid and substantial decrease in sludge flow velocity. The dimensions of gravity chamber 1202 are arranged to provide time for grit to settle in the gravity chamber prior to discharge of the sludge. Periodically valve 1205 is opened to remove accumulated grit from gravity separation chamber 1202 . Preferably, valve 1205 is a pinch valve to avoid fouling and failure associated with grit becoming lodged in a valve seat.
With reference to FIG. 5 , sludge substantially free from grit exits the grit separator and is fluidly communicated to sludge classification press via pipe 20 b . The sludge classification press 52 may be a rotary screw press such as the Strainpress® Sludgecleaner SP manufactured by Huber Technology. In one embodiment, sludge classification press 52 removes all solids larger than 1.6 mm from the sludge. In alternate embodiments, the sludge classification press 52 removes solids with dimensions that range from 0.15 mm to 10 mm. In one embodiment the compression and sheering of the sludge by the sludge classification press 51 releases biologically-digestible material from items such as corn kernels while removing the indigestible or less rapidly digestible materials such as the outer layer of a corn kernel.
After treatment with sludge classification press 52 , the solids content of the sludge consists primarily of biologically-digestible materials that can be digested in a digester to produce energy-rich bio-gases such as methane. The removal of materials that are not biologically digestible increases the rate of digestion of the remaining materials, enabling greater throughput and processing of sludge by a digester. The removal of non-digestible materials reduces the frequency with which digesters need to be taken off line and cleaned.
In some applications, it may be desirable to increase the concentration of biologically-digestible material in the sludge after treatment by the sludge classification press 52 and prior to digestion to improve the efficiency of digestion, maintain a low hydraulic retention rate (HRT), and increase the volume of production of bio-gases, such as, by way of example and not limitation, methane. Optionally, a flocculent may be added to the sludge via flocculent source 55 after treatment of the sludge by sludge classification press 52 . The flocculent is added to the sludge to create flocs from dissolved and suspended biologically-digestible materials, thereby increasing the concentration of biologically-digestible materials to improve performance of the digesters that digest the resultant sludge. By way of example, in a municipal waste water treatment plant a representative range for the total solids content the sludge after treatment by sludge classification press 52 is between two and three percent, whereas a digester may operate more efficiently with a total solids content of five to seven percent, and some as much as ten percent or more, depending upon the type of digester. Current systems use total solids as a surrogate measure for the concentration of biologically-digestible organic material in sludge. Gas production comes from volatile solids (VS) which are approximately 70-80% percent of the total solids. In one embodiment of the system, the treated sludge from the sludge classification press is fluidly communicated to solids concentrator 53 via pipe 20 c . Devices to increase solids content of sludge are well known in the art. By way of example and not limitation, solids concentrator 53 may comprise a gravity deck thickener, rotary drum thickener, or a rotary screw press. Sludge thickener 53 increases the solids content of the sludge treated by sludge classification press 52 .
With reference to FIG. 7 , in one embodiment IFS 100 - 107 discharge pipes 570 - 577 and clarification tank 30 discharge pipe 70 are in fluid communication with sludge and grit intake pipe 20 which is in fluid communication with sludge pump 50 . Sludge Pump 50 is in fluid communication with grit separator 51 via pipe 20 a . Grit separator 51 is in fluid communication with sludge classification press 52 via pipe 20 b . In one embodiment, sludge classification press 52 is in fluid communication with optional sludge thickener 53 via pipe 20 c . Optionally, a flocculent source 55 is arranged to communicate flocculents to sludge traversing pipe 20 c . Optional sludge thickener 53 is in fluid communication with digester 54 via pipe 20 d and wet well 12 of FIG. 1 via pipe 22 . In one embodiment, sludge pump 50 is in communication with and controlled by SCADA 900 via communication channel 926 . In one embodiment, sludge pump 52 is in communication with and controlled by SCADA 900 via communication channel 926 . In one embodiment, flocculent source 55 is in communication with and controlled by SCADA 900 via communication channel 929 . In one embodiment, sludge thickener 53 is in communication with and controlled by SCADA 55 via communication channel 928 .
In one embodiment, sludge classification press (SCP) 52 is in fluid communication with digester 54 via pipe 20 c.
In one embodiment, digester 54 is an anaerobic digester. Sensor 64 is arranged to measure aspects of the operation of digester 54 . Sensor 64 is in communication with SCADA 900 via communication channel 944 . Sensor 64 may be one or more of temperature sensors, carbon-dioxide sensors, oxygen sensor, pH sensor, methane sensor, or any other sensor suitable for measuring the physical condition and characteristics, and chemical properties of the materials undergoing digestion.
To optimize overall operations of the system and to detect indications of existing or imminent component or system failure, in one embodiment the characteristics of the sludge are measured by sensor 64 as the sludge is treated. Bacteria in an anaerobic digester thrive best when supplied with food at constant concentration and flow rate. If the rate of organics of solid being supplied to the digester 54 goes outside of the desired ranges as measured by one or more sensors 60 , 61 , 62 , SCADA 900 adjusts the throughput of the sludge classification press 52 as needed. If the organics/solids ratios are too low, as measured by one or more sensors 60 , 61 , 62 , SCADA 900 increases the dosage supplied by flocculent source 55 . If the organics/solids ratios are too high, as measured by one or more sensors 60 , 61 , 62 , SCADA 900 decreases or stops the dosage supplied by flocculent source 55 . In one embodiment, as single sampling well and set of sensors are used to minimize cost associated with sensors and simplify issues of cross-sensor calibration and correlation across multiple sensors deployed throughout the system.
Sampling pump 56 is in fluid communication with pipes 20 a - 20 d via pipe 21 . Sampling pump 56 is preferably a positive displacement pump such as a diaphragm pump or progressive cavity pump in order to prevent fouling. Valves 7 a - 7 d control fluid communication between pipes 20 a - 20 d and pipe 21 . In one embodiment, valves 20 a - 20 d are manually operated. In one embodiment, valves 20 a - 20 d are controlled by and in communication with SCADA 900 via communication channels 935 a - 935 d . In one embodiment, sampling pump 56 is controlled by and in communication with SCADA via communication channel 931 . Sampling pump 56 is in fluid communication with sampling well 57 via pipe 21 . One or more sensors 60 , 61 , 62 are arranged in sampling well 57 to measure various characteristics of materials in sampling well 57 . The one or more sensors are controlled by and in communication with SCADA 900 via communication channels 932 , 933 , 934 . Sampling well 23 is in fluid communication with wet well 12 of FIG. 1 via pipe 23 .
Sludge from IFS 100 - 107 and clarification tank 30 is treated in a substantially similar manner by sludge pump 50 , sludge classification press 52 , solids concentrator 53 , and flocculent source 55 as described hereinabove with respect to FIG. 5 . Upon final treatment of the sludge by sludge classification press 52 , or optional sludge thickener 53 , as applicable, the sludge is fluidly communicated to digester 54 .
Sludge removed from IFS 100 - 107 and clarification tank 30 is sampled as it is discharged from sludge pump 50 via pipe 20 a . In one embodiment, SCADA 900 closes valves 7 b , 7 c , 7 d, opens valve 7 a and turns sampling pump 56 on to withdraw sludge via pipe 21 . Sludge is pumped via sampling pump 21 to sampling well 57 where one or more sludge characteristics are measured via one or more sensor 60 , 61 , 62 . Upon completion of the measurements, the sludge sample is discharged via discharge pipe 23 . In a similar manner, one or more characteristics of grit-free sludge are sampled as the sludge is discharged from grit separator 51 via pipe 20 b . In one embodiment, SCADA 900 closes valves 7 a , 7 c , 7 d , opens valve 7 b , and turns sampling pump 56 on to withdraw sludge via pipe 21 . Sludge is pumped via sampling pump 21 to sampling well 57 where sludge characteristics are measured via one or more sensors 60 , 61 , 62 . Upon completion of the measurements, the sludge sample is discharged via discharge pipe 23 . One or more characteristics of classified sludge are measured as the sludge is discharged from sludge classification press 52 via pipe 20 c . In one embodiment, SCADA 900 closes valves 7 a , 7 b , 7 d , opens valve 7 c and turns sampling pump 56 on to withdraw sludge via pipe 21 . Sludge is pumped via sampling pump 21 to sampling well 57 where one or more sludge characteristics are measured via one or more sensors 60 , 61 , 62 . Upon completion of the measurements, the sludge sample is discharged via discharge pipe 23 . One or more characteristics of concentrated sludge are measured as the sludge is discharged from solids concentrator 53 via pipe 20 d . In one embodiment SCADA 900 closes valves 7 a , 7 b , 7 c , opens valve 7 d , and turns sampling pump 56 on to withdraw sludge via pipe 21 . Sludge is pumped via sampling pump 21 to sampling well 57 where one or more sludge characteristics are measured via one or more sensor 60 , 61 , 62 . Upon completion of the measurements, the sludge sample is discharged via discharge pipe 23 .
In an alternate embodiment, and with reference to FIG. 8 , only the sludge from IFS' 100 - 107 is treated by a grit separator as the sludge in clarification tank 30 is substantially free of grits and other dense solids. IFS 100 - 107 discharge pipes 570 - 577 are in fluid communication with sludge processing intake pipe 20 ′ and sludge pump 50 ′. Sludge pump 50 ′ is in fluid communication with grit separator 51 via pipe 20 f. Grit separator 51 is in fluid communication with sludge classification press 52 via pipe 20 g . Clarification tank 30 discharge pipe 70 is in fluid communication with sludge pump 50 . Sludge pump 50 is in fluid communication with grit separator 51 via pipe 20 e.
In an alternate embodiment and with reference to FIG. 9 , the content of biologically-digestible materials in sludge from the IFS' 100 - 107 is insignificant relative to the cost of extraction from the sludge. IFS 100 - 107 discharge pipes 570 - 577 are in fluid communication with sludge processing intake pipe 20 ′ and sludge pump 50 ′. Sludge pump 50 ′ is in fluid communication with grit separator 51 via pipe 20 f . Grit separator 51 separates the grits and particulates from the liquid. Liquid and non-particulate, non-grit sludge extracted from the sludge by grit separator 51 are returned to wet well 12 of FIG. 1 via discharge pipe 26 , and grit is disposed of in a landfill or by other means.
In another alternate embodiment, and with reference to FIG. 10 where substantive biologically-degradable material settles in IFS 100 IFS troughs 201 , 202 , but not in IFS 100 grit box 500 , IFS trough 201 , 202 discharge pipes 271 , 272 may be arranged to be in fluid communication with sludge process intake pipe 20 in communication with sludge pump 50 while grit box discharge pipe 570 is arrange to be in fluid communication with sludge processing intake pipe 20 ′ in fluid communication with sludge pump 51 ′ for further treatment, as shown by way of example and not limitation in FIG. 8 and FIG. 9 .
In a waste water treatment plant, the composition of the sludge settled in the IFS troughs, grit box, and clarification tank can change over time as a result of variations in the composition of the influent, changes in plant operating conditions, and other factors such as temperature and relative humidity. With reference to FIG. 11 , to provide flexibility in the treatment of sludge from clarification tank 30 , if the sludge has substantially no grit, discharge pipe 70 may be placed in fluid communication with sludge pump 50 by opening valve 36 and closing valve 35 , resulting in the sludge bypassing grit separator 51 . Check valve 47 prevents the sludge in discharge pipe 70 from entering sludge and grit intake pipe 20 ′ via pipe 20 i . Alternatively, if there is a need to separate grit from sludge in clarification tank 30 , discharge pipe 70 is placed in fluid communication with sludge pump 50 ′ by opening valve 35 and closing valve 36 . Check valve 49 prevents sludge from clarification tank 30 flowing into IFS' 100 - 107 via sludge and grit intake pipe 20 ′. Similarly, to provide flexibility in the treatment of sludge from IFS' 100 - 107 , if the sludge has substantially no grit, sludge and grit intake pipe 20 ′ may be placed in fluid communication with sludge pump 50 by opening valve 37 and closing valve 38 , resulting in the sludge bypassing grit separator 51 . Check valve 46 prevents the sludge from IFS′ 100 - 107 flowing back into clarification tank 30 via discharge pipe 70 . Alternatively, if there is a need to separate grit from sludge in the IFS' 100 - 107 , sludge and intake pipe 20 ′ is placed in fluid communication with sludge pump 50 ′ by opening valve 38 and closing valve 37 . Check valve 48 prevents sludge from IFS' 100 - 107 flowing into clarification tank 30 via discharge pipe 70 .
Similarly, in a waste water treatment plant the amount of biologically-degradable material associated with sludge processed by grit separator 51 may change over time as a result of variations in the composition of the influent, changes in plant operating conditions and other factors such as flows from precipitation, snow melt, industrial discharges, and significant public events such as a surge in the use of toilets during Super Bowl halftime.
With reference to FIG. 9 , IFS 100 - 107 discharge pipes 570 - 577 are in fluid communication with sludge and sludge intake pipe 20 ′ which is in fluid communication with sludge pump 50 ′. IFS 100 - 107 discharge pipes 570 - 577 are in fluid communication sludge pump 50 via sludge and intake pipe 20 ′ which is in fluid communication with pipe 20 i which is in fluid communication with clarification tank 30 discharge pipe 70 which is in direct fluid communication with sludge pump 50 . Valve 38 is positioned in pipe 20 ′ to control the flow of materials from discharge pipes 570 - 577 to sludge pump 50 ′ and not to affect the fluid communication of materials between discharge pipes 570 - 577 and sludge pump 50 and between clarification tank 30 discharge pipe 70 and sludge pump 50 as described hereinbelow. Valve 37 is positioned in pipe 20 i to control the flow of materials from IFS 100 - 107 discharge pipes 570 - 577 to sludge pump 50 . Valve 37 and pipe 20 i are arrange to have no effect on the fluid communication between clarification tank 30 ′ discharge pipe 70 and sludge pump 50 and between clarification tank 30 discharge pipe 70 and sludge pump 50 ′.
Valve 36 is positioned to control the flow of materials in discharge pipe 70 to sludge pump 50 and to have no effect on the fluid communication of materials between pipe 20 ′ and sludge pump 50 ′ or on the fluid communication of materials between discharge pipe 70 and sludge pump 50 .
Clarification tank 30 discharge pipe 70 is in fluid communication with sludge pump 50 . Clarification tank 30 discharge pipe 70 is in fluid communication with sludge pump 50 ′ via pipe 20 h which is communication with pipe 20 ′. Valve 36 is positioned in discharge pipe 70 to control the fluid communication of materials in discharge pipe 70 with sludge pump 50 and to have no effect on the fluid communication between materials in discharge pipe 70 and sludge pump 50 ′ and to have no effect on fluid communication of materials in discharge pipes 570 - 577 and sludge pump 50 . Valve 35 is positioned in pipe 20 h to control the fluid communication of materials in discharge pipe 70 to sludge pump 50 ′ and to have no effect on the fluid communication of materials between discharge pipe 70 and sludge pump 50 . Valve 35 and pipe 20 h are positioned so as to have no effect on the fluid communication between materials in discharge pipes 570 - 577 and sludge pump 50 ′ via pipe 20 ′.
Flap valve 46 is positioned in discharge pipe 70 between clarification tank and valves 35 , 36 to prevent the reverse flow of materials in discharge pipe 70 when valves 35 or 36 are opened, preventing the fluid communication of materials between clarification tank 30 and IFS 100 - 107 . Flap valve 47 is positioned in pipe 20 i to prevent the reverse flow of materials through pipe 20 i when valve 37 is opened, preventing the fluid communication of materials from clarification 30 discharge pipe 70 with sludge pump 50 ′ and IFS troughs 100 - 107 via pipe 20 i. Flap valve 48 is positioned in pipe 20 h to prevent the reverse flow of materials through pipe 20 h when valve 35 is opened, preventing the fluid communication of materials from IFS troughs 100 - 107 with clarification tank 30 and sludge pump 50 via pipe 20 h . Flap valve 49 is positioned in grit and sludge intake valve 20 ′ to prevent the reverse flow of materials in sludge and intake pipe 20 ′, preventing fluid communication of materials from clarification tank 30 and IFS troughs 100 - 107 .
Sludge pump 50 is in fluid communication with sludge classification press 52 via pipe 20 e . Sludge pump 50 ′ is in communication with grit separator 51 via pipe 20 f . Grit separator 51 discharges grit-free sludge via pipe 20 g and is in communication with sludge classification press 52 via pipe 20 g. Alternatively grit separator 51 discharges grit-free pipe via pipe 26 and is in fluid communication with wet well 12 of FIG. 1 via pipe 26 . Grit Separator 51 discharges grit via discharge pipe 24 . Valve 39 is positioned on pipe 20 g to control fluid communication between grit separator 51 and sludge classification press 52 . Valve 43 is positioned on pipe 26 to control fluid communication between grit separator 51 and wet well 12 of FIG. 1 .
Sludge classification press 52 is in fluid communication with optional sludge thickener 53 via pipe 20 c . Optional solids concentrator 53 is in fluid communication with digester 54 via pipe 20 d . In one embodiment, sludge thickener is in direct fluid communication with digester 54 via pipe 20 c .
Valves 35 - 39 may be manually operated valves. In one embodiment, valves 35 - 39 are electronically-controlled valves under control of and in communication with SCADA 900 via communication channels 945 - 949 respectively. Valves 43 may be a manually operated valve. In one embodiment, valve 43 is an electronically-controlled valve under control of and in communication with SCADA 900 via communication channel 950 .
With reference to FIG. 11 , to provide flexibility in the treatment of sludge processed by grit separator 51 , if the sludge has substantially no biologically-degradable materials, valve 39 providing fluid communication between grit separator 51 and sludge classification press 52 remains closed. Valve 43 is opened and liquid and non-particulate, non-grit sludge extracted from the sludge by the grit separator 51 is returned to wet well 12 of FIG. 1 via discharge pipe 26 and grit is disposed of in a landfill or by other means. If the sludge has substantive biologically-degradable materials, valve 39 providing fluid communication between grit separator 51 and sludge classification press 52 is opened and valve 43 is closed. Liquid and non-particulate, non-grit sludge extracted from the sludge by the grit separator 51 is then treated by sludge classification press 52 and grit is disposed of in a landfill or by other means.
In one embodiment of the current application, sludge and grit that has not otherwise been separated into components by a primary treatment system is treated to remove grits and other undesirable materials and to separate and concentrate biologically digestible materials. With reference to FIG. 4 , discharge pipe 1111 of primary treatment system 1100 is in fluid communication with sludge and grit intake pipe 20 of FIG. 12 . In one embodiment, a sludge pump 50 is used to assist in the evacuation of the primary treatment system 1100 sludge. In one embodiment, sludge pump 50 is electronically controlled by a supervisory control and data acquisition system SCADA 900 which provides a signal via communication channel 926 to start and stop pumping.
A sludge treatment system may receive sludge with varying characteristics during its operation. In a waste water treatment system, the characteristics of the sludge may vary due to seasonal and diurnal variations in the characteristics of the influent as well as from periodic and/or isolated events. A storm may result in flushing of grit and particulates from a sewer system connected to the waste water treatment system. An industrial emitter may periodically discharge low grit materials rich in biologically-digestible materials into a sanitary sewer system connected to a waste water treatment plant. Clarification systems such as the prior art CLARI-FLOCCULATOR® system of FIG. 4 may be used to treat sites containing waste water that are remote or otherwise not directly connected to a waste water treatment system. In these circumstances, the sludge produced by treatment of the waste water may need to be transported to a sludge treatment system. It may be desirable to regularly or periodically treat secondary sludge to remove biologically-digestible materials as well as primary sludge. A waste treatment plant may accept food and other wastes with an exceptionally high proportion of biologically-digestible material trucked or otherwise transported directly to the plant. For these and other reasons, it is desirable to have an adaptive, configurable sludge treatment system.
With reference to FIG. 12 , in one embodiment of the current application, sludge enters grit intake pipe 20 which is in fluid communication with sludge pump 50 . Sludge pump 50 is in fluid communication with grit separator 51 via pipe 20 a. Valve 66 is arranged in line with pipe 20 a to control fluid communication to grit separator 51 . Grit separator 51 is in fluid communication with sludge classification press 52 via pipe 20 b . Valve 84 is arranged in line with pipe 20 b to control fluid communication to sludge classification press 52 . Sludge classification press 52 is in fluid communication with sludge thickener 53 via pipe 20 c . Valve 86 is arranged in line with pipe 20 c to control fluid communication to sludge thickener 53 . Sludge thickener 53 is in fluid communication with digester 54 via pipe 20 d . A flocculent source 55 is arranged to communicate flocculents to sludge prior to being treated by sludge classification press 52 via pipe 27 a or alternatively to sludge discharged from sludge classification press 52 via pipe 27 b . In one embodiment, sludge pump 50 is in communication with and controlled by SCADA 900 via communication channel 926 . In one embodiment, sludge classification press 52 is in communication with and controlled by SCADA 900 via communication channel 927 . In one embodiment, flocculent source 55 is in communication with and controlled by SCADA 900 via communication channel 929 . In one embodiment, sludge thickener 53 is in communication with and controlled by SCADA 900 via communication channel 928 .
In one embodiment, one or more optional flowmeters are incorporated in the system: flow meter 2009 to measure the flow in discharge pipe 20 ; flow meter 2001 to measure the flow in pipe 20 a , flow meter 2003 to measure the flow in discharge pipe 20 b; flow meter 2005 to measure the flow in pipe 20 c; and flow meter 2007 to measure the flow in pipe 20 d . In one embodiment, flow meter 2009 is in communication with SCADA 900 via communication channel 951 . In one embodiment, flow meter 2001 is in communication with SCADA 900 via communication channel 936 . In one embodiment, flow meter 2003 is in communication with SCADA 900 via communication channel 938 . In one embodiment, flow meter 2005 is in communication with SCADA 900 via communication channel 940 . In one embodiment, flow meter 2007 is in communication with SCADA 900 via communication channel 942 .
In one embodiment, one or more optional sensors are incorporated in the system: sensor 2010 to measure the characteristics of materials in sludge and grit intake pipe 20 ; sensor 2002 to measure the characteristics of materials in discharge pipe 20 a; sensor 2004 to measure the characteristics of materials in discharge pipe 20 b; sensor 2006 to measure the characteristics of materials in discharge pipe 20 c; and, sensor 2008 to measure the characteristics of materials in discharge pipe 20 d . The optional sensors are in communication with SCADA 900 : sensor 2010 via communication channel 952 ; sensor 2002 via communication channel 937 ; sensor 2004 via communication channel 939 ; sensor 2006 via communication channel 941 ; and sensor 2008 via communication channel 943 .
Sensors 2010 , 2004 , 2006 , and 2008 may be a UVAS sensor, turbidity sensor, pH sensor or solids sensor or any other sensor consistent with measuring the physical and/or chemical characteristics of sludge and grits undergoing treatment.
Pipe 20 a is in direct fluid communication with pipes 20 a , 20 b , 20 c , and pipe 20 d via pipe 20 j . Valve 64 controls fluid communication between pipe 20 a and pipe 20 j . Valve 65 controls fluid communication between pipe 20 j and pipe 20 b. Valve 85 controls fluid communication between pipe 20 j and pipe 20 c . Valve 87 controls fluid communication between pipe 20 j and pipe 20 d . Valve 69 controls the communication of grit discharged through grit separator 51 grit discharge pipe 24 . In one embodiment, valves 64 , 65 , 66 , 69 , 84 , 85 , 86 , 87 are manually controlled. In one embodiment, valves 64 , 65 , 66 , 69 , 84 , 85 , 86 , 87 are under the control of and in communication with SCADA 900 : valve 64 via communication channel 953 , valve 65 via communication channel 955 ; valve 66 via communication channel 954 ; valve 69 via communication channel 957 ; valve 84 via communication channel 958 ; valve 85 via communication channel 959 ; valve 86 via communication channel 960 ; and, valve 87 via communication channel 961 .
Check valve 68 is arranged in line with pipe 20 b to permit flow of fluid from grit separator 51 to sludge classification press 52 and to pipe 20 j where pipe 20 j is in fluid communication with pipe 20 b and while preventing the reverse flow of fluid to grit separator 51 . Check valve 88 is arranged in line with pipe 20 c to permit flow of fluid from sludge classification press 52 to solids concentrator 53 and to pipe 20 j where pipe 20 j is in fluid communication with pipe 20 c while preventing the reverse flow of fluid to sludge classification press 52 . Check valve 89 is arranged in line with pipe 20 d to permit flow of fluid from sludge thickener 53 to digester 54 and to pipe 20 j where pipe 20 j is in fluid communication with pipe 20 d while preventing the reverse flow of fluid to sludge thickener 53 .
The system of FIG. 12 operates in substantially the same manner as the corresponding elements of FIG. 5 when valves 64 , 65 , 85 and 87 are closed and valves 66 , 84 , 86 and 87 are opened. The system is dynamically configured to optimally and most efficiently separator biological materials from the incoming sludge by a combination of continuous monitoring of the sludge characteristics undergoing treatment and a priori knowledge of the sludge characteristics. By way of example, upon receiving sludge from an industrial beverage or food processing source known to have little grit and high solids content, the sludge treatment system of FIG. 12 may be configured to route material past the grit separator and sludge thickener by closing valves 66 and 84 and opening valves 64 , 65 , 84 , 86 and 87 . Upon receiving sludge known to have a great deal of grit, but little biologically-digestible materials, the sludge treatment system of FIG. 12 may be configured to separate grit from the fluid and discharge both by closing valves 64 , 65 and 84 and opening valve 69 .
While the invention has been described by reference to various specific embodiments, it should be understood that numerous changes may be made within the spirit and scope of the inventive concepts described. Accordingly, it is intended that the invention not be limited to the described embodiments, but will have full scope defined by the language of the following claims. | A system comprising method and apparatus for separating biologically-digestible materials from an influent sewage stream. The system may comprise a primary clarification tank to capture sixty percent or more of the total solids from an influent stream; a sludge classifying press (SCP) to isolate and concentrate biologically digestible materials from sludge formed in the primary clarification tank, releasing valuable organics, such as are found in corn kernels, by fracturing the protective casings; a grit capture mechanism in a chamber within the primary clarification tank and isolated from the bulk of the sludge containing biologically-degradable materials; a grit trap to remove grit from the sludge prior to classifying the sludge with the SCP; apparatus for adding thickener to the sludge after classification and prior to digestion; and automation of one or more elements of the process for separating and digesting the biologically digestible materials in an influent stream. | 2 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority from the provisional application Ser. No. 61/311,072 which was filed Mar. 5, 2010, the entire contents of which are incorporated herein by reference.
GOVERNMENT INTERESTS
[0002] This invention was made with U.S. government support under USDA-CSREES Awards Nos. 2008-34467-19445 and 2009-34467-20151. The government has certain rights in the invention.
BACKGROUND OF THE INVENTION
[0003] For purposes of this invention disclosure, the terms “lipid-soluble” and “lipophilic” refer to compounds or substances which are capable of dissolving in fats, oils, lipids, or non-polar solvents. The terms “lipid-soluble” and “lipophilic” are used interchangeably, and the term “lipophile” refers to a substance which is lipophilic.
[0004] Delivery of lipid-soluble materials such as vitamins A, D, E and K, fatty acids and lipid-soluble pharmaceuticals into the human (or animal) body remains a challenge. It can be difficult to maintain lipid-soluble nutrients in low-fat foods because they do not remain in solution and/or they adsorb to packaging materials (Swaisgood et al., 2001). Existing commercial delivery and fortification strategies revolve around emulsification and microencapsulation, both of which have limitations. Emulsification requires product-specific emulsifiers, many of which are not GRAS (Generally Recognized As Safe). Microencapsulation materials, such as cyclodextrins, are often expensive. In addition, these approaches invariably require using a substantial amount of fat as carriers for lipid-soluble materials.
[0005] The need for new carriers for lipid-soluble materials has become particularly apparent, given the recent resurgence of vitamin D deficiencies. Vitamin D is associated with bone health, myocardial development, brain and fetal development and reduced cancer risk. While the needs are evident, the means to incorporate vitamin D remain limited, at least in part due to the fact that vitamin D is sensitive to acid, oxygen, and light. Fortification of lipid-soluble vitamins, such as vitamin D, is challenging given their sensitive chemical nature. The presence of conjugated double bonds in vitamin D provides an easy route for decomposition by oxidation. Isomerization can occur under acidic or light conditions. Temperatures above 40° C. and relative humidity above 85% can deteriorate it, while mild acidification can isomerizes it to inactive forms.
[0006] Similarly, fortification of foods and beverages with fatty acids, such as polyunsaturated Ω-3 fatty acids, is very challenging because the fatty acids are highly insoluble in water and very sensitive to oxidative degradation which can reduce their health benefits and cause undesirable odors (Zimet et al., 2009).
[0007] Protein-based carriers offer a potential alternative to existing carriers, although the limited research to date on protein carriers has focused on dairy proteins. Wang et al. (1997) reported that beta-lactoglobulin, the major protein in whey, showed substantially greater binding affinity to vitamin D 2 than to vitamin A. They did not, however, report being able to produce a complex using beta-lactoglobulin and a vitamin. They also did not provide binding efficiency data which would indicate what proportion of the available vitamins the protein was able to bind.
[0008] Swaisgood et al. (2001) also used beta-lactoglobulin to form a complex with vitamin D. While they were able to form a complex which was soluble in aqueous solution, their approach involved affinity purification methods, including use of affinity chromatography in their preferred method, which would be cost-prohibitive for commercial applications. The authors also did not provide information about the proportion of the added vitamin D which was retained in the complex along with beta-lactoglobulin.
[0009] Zimet et al. (2009) noted that certain food proteins, particularly milk proteins, had an ability to bind to hydrophobic molecules, making them useful for the encapsulation and delivery of bioactive compounds. They reported that beta-lactoglobulin had been found to bind with vitamin D, retinoic acid, cholesterol and various aromatic compounds and fatty acids. They noted, though, that there had been no prior published work on the binding of proteins to Ω-3 fatty acids. Using a complex containing beta-lactoglobulin and pectin, they reported an encapsulation efficiency for DHA (docosahexaenoic acid) of approximately 64% (i.e., amount of DHA encapsulated as a percent of the initially added DHA).
[0010] Semo et al. (2007) attempted to use microencapsulation involving pure casein micelles. They wrote that the use of casein micelles as carriers for nutraceuticals had not yet been reported in the literature. However, they were only able to encapsulate approximately 27% of the analytically recovered vitamin D 2 which they had added to a suspension containing casein micelles.
[0011] The inventors of the present invention have unexpectedly found that using a plant-based protein, leaf protein, they were able to create a leaf protein-vitamin D complex which retained approximately 85% of the vitamin D contained in a mixture—more than three times greater percentages of vitamin D than is reported from casein micelles. The present invention pertains specifically to the use of leaf proteins in a complex with lipid-soluble materials.
[0012] The term “leaf protein” as used in this invention disclosure is intended to refer to all water-soluble proteins contained in plant leaves. The leaf protein may be obtained from any green leafy plant, as it is well known that all chlorophyll-containing plants contain soluble leaf proteins. Examples of such plants include, but are not limited to, tobacco, alfalfa and spinach. Lo et al. (2008) and Fu et al. (2010) have described a method for efficiently recovering and preparing a leaf protein powder from the leaves of green plants. Leaf protein may be extracted from plants, and a suitable leaf protein powder prepared, using the method described in Lo et al. (2008), which is incorporated by reference, or using other methods which may be known to practitioners of the art.
[0013] Leaf proteins—the proteins which occur naturally in the leaves of green plants—are perhaps the most abundant proteins in nature. They contain excellent binding, gelling, foaming, whipping and emulsifying characteristics, and have nutritional value comparable to milk protein (Lo et al., 2008; Sheen et al., 1991). Leaf protein carriers also offer another advantage over other proteins in that consumers do not have to worry about whether the products contain animal-origin or dairy-based ingredients. Leaf protein is therefore a very desirable carrier for the delivery of lipophilic substances.
SUMMARY OF THE INVENTION
[0014] This invention provides a novel composition of matter comprising a complex of leaf protein and one or more lipid-soluble materials. The present invention also provides methods of making and using such complexes.
[0015] Complexes of the invention typically comprise leaf protein and one or more lipid-soluble materials such as, for example, vitamins A, D, E, and K, fatty acids, lipid-soluble pharmaceuticals, or other lipid-soluble materials. In a preferred embodiment, the complex is a powdery solid material. This complex is useful as a carrier for the delivery of lipid-soluble materials, into or onto humans or animals. A non-limiting list of examples for the possible uses of this leaf protein-lipid-soluble material complex are as a food or in food as a delivery system for vitamins or other lipid-soluble materials; in dietary supplements and nutraceuticals, infant formulas, in pharmaceuticals or in topical compositions. Nutrient and vitamin supplements can be in any form known in the art, including but not limited to, powders, tablets (chewable or otherwise), capsules, gel-caps, elixirs, and effervescent tablets. Alternatively, nutrient and vitamin supplements can be in the form of bars, drinks, juices or shakes, among others. These and other aspects of the present invention are disclosed in more detail in the description of the invention below.
[0016] The inventors were able to produce a leaf protein-vitamin D 3 complex which retained approximately 85% of the vitamin D added to a mixture, using a preferred embodiment of the claimed method. (See FIG. 1 ). This result indicates that leaf protein is highly effective and efficient as a carrier of lipid-soluble materials. Without wishing to be bound by theory, this result also indicates that leaf protein has many binding sites, and is able to carry large amounts of target lipid-soluble materials.
[0017] Methods of the invention typically comprise preparing a suspension containing leaf protein. Optionally, non-water-soluble materials may be removed from the leaf protein suspension. Lipid-soluble materials may then be mixed with the suspension. Optionally, lipid-soluble materials may be prepared by dissolving them in a solvent prior to their addition to the suspension. When the leaf protein suspension and the lipid-soluble materials have been suitably combined, they may be further treated. In one embodiment, the mixture may be frozen and, optionally, lyophilized. In some embodiments, the mixture may be dried without freezing using techniques well known in the art, for example, spray drying. In some embodiments, the mixture is dried into a powder. The resulting product is a solid powder containing a complex of leaf protein and the target lipid-soluble material(s).
BRIEF DESCRIPTION OF THE FIGURES
[0018] FIG. 1 : Comparison of vitamin D 3 recovery in freeze-dried formulation: with tobacco leaf protein vs. control.
[0019] FIG. 2 : Comparison of vitamin D 3 recovery, and crude protein % in vitamin D-tobacco leaf protein complex of different water content.
[0020] FIG. 3 : Comparison of vitamin D 3 recovery, and crude protein % in vitamin D-tobacco leaf protein complex of varying pH.
[0021] FIG. 4 : Solubility values of vitamin D-tobacco leaf protein complex formulated at different pH (p value=0.0709).
[0022] FIG. 5 : Comparison of vitamin D 3 recovery and crude protein % in the vitamin D-tobacco leaf protein complex under different mixing conditions.
DETAILED DESCRIPTION OF INVENTION
[0023] The principles, preferred embodiments and modes of operation of the present invention will be described hereunder. The invention which is intended to be protected herein should not, however, be construed as limited to the particular forms disclosed, as 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. Accordingly, the examples, descriptions, and best mode of carrying out the invention given below should be considered exemplary in nature and not as limiting to the scope and spirit of the invention as set forth in the claims.
[0024] The objective of the methods of this invention is to produce a complex containing leaf protein and one or more lipid-soluble substances. The present invention may be used to prepare complexes consisting of leaf protein and any other lipid-soluble materials, including but not limited to, vitamins D 3 , A, E, K, other types of vitamin D, fatty acids such as DHA, eicosapentaenoic acid, linoleic acid, and alpha-linoleic acid, lipid-soluble drugs (some of which are listed below), cholesterol, retinol and retinoids and other lipophilic substances. In some embodiments, complexes of the invention may comprise 2, 3, 4, 5, or more lipid-soluble materials.
[0025] The term “target substance” as used in this invention disclosure refers to the particular lipid-soluble substance(s) which the practitioner wishes to form into a complex with leaf protein.
[0026] The present invention is based on the discovery that leaf protein very efficiently forms complexes with lipophilic substances, for example vitamin D. This property allows the use of leaf protein as a carrier for lipophilic nutrients in foods, dietary supplements and nutraceuticals, infant formulas, drugs and pharmaceuticals and topical compositions.
[0027] Lipid-soluble materials may be derived from any source known in the art, for example, the vitamin A, vitamin D, vitamin E, and vitamin K as used herein can be from any source known in the art. The term “vitamin A” as used herein refers to any form of vitamin A, including but not limited to, retinol, retinaldehydes, retinal, retinoic acid (also known as tretinoin and retin-A), and vitamin A salts and derivatives (e.g., retinol palmitate, retinyl acetate, and β-carotene and other carotenoids). The term “vitamin D” as used herein refers to any form of vitamin D, including but not limited to, ergocalciferol (D 2 ), cholecalciferol (D 3 ), 22,23-dihydroergocalciferol (D 4 ), and vitamin D salts and derivatives (e.g., 25-hydroxycholecalciferol and 1-α,25-dihydroxycholecalciferol). The term “vitamin E” as used herein refers to the family of compounds known as tocopherols (e.g., α-tocopherol, β-tocopherol, δ-tocopherol, γ-tocopherol), as well as tocol, tocoquinone, tocotrienol, and vitamin E salts (e.g., vitamin E phosphate) and derivatives (e.g., tocopherol sorbate, tocopherol acetate, tocopherol succinate, other tocopherol esters). As used herein, the term “vitamin K” refers to vitamin K 1 (phytonadione), vitamin K 2 (menaquinone), vitamin K 3 (menadione), vitamin K 4 , vitamin K 5 , vitamin K 6 , vitamin K 7 , and their salts and derivatives.
[0028] Fatty acids refer to carboxylic acids with a long unbranched aliphatic tail, and which are either saturated or unsaturated. Fatty acids include, but are not limited to DHA, eicosapentaenoic acid, linoleic acid, and alpha-linoleic acid, amongst many others.
[0029] Leaf protein powder suitable for practicing this invention may be obtained from plant leaves using the method described in Lo et al. (2008) and Fu et al. (2010), or using any other method of leaf protein processing or extraction which may be known to practitioners in the art.
[0030] One suitable method for preparing leaf protein is as follows:
[0031] Freshly harvested green plant leaves may be chopped with a hammermill. The leaves can be either freshly harvested, or they can be stored in a cool or frozen state or dried following harvest until they are ready for processing. Alternatively, physical maceration procedures, combined with mechanical pressure, can be utilized to disrupt the cell wall and prepare the proteins for solubilization.
[0032] Substantially simultaneously with the leaf rupturing, a buffer solution is added to the leaves. The inventors found that a solution containing sodium phosphate dibasic and potassium phosphate monobasic (Na 2 HPO 4 —KH 2 PO 4 ) is especially effective, although other effective buffering agents may be used. The inventors also found that a pH of 7.77 is preferable as it gave the highest protein yields with this agent, although a pH range between approximately 7.4-8.0 or even 6.5-9.0 is acceptable.
[0033] It is preferred that the buffer should have a low concentration, in order to avoid precipitating or denaturing the proteins. It was found that a buffer concentration of approximately 0.067M was the optimal concentration, although a range of 0.025M to about 0.3M is quite acceptable, and more preferably a range of about 0.067M-about 0.2 M.
[0034] It is preferred that the buffer solution should also contain both a chelating agent and a reducing agent. The purpose of the chelating agent is to remove loose ions from the resulting juice. We have found that 10 mM of EDTA, a well-known chelating agent, is effective to recover loose ions. The purpose of the reducing agent is to prevent oxidation and denaturation of the proteins. We have also found that 25 mM of 2-mercaptoethanol is effective as a reducing agent.
[0035] The ruptured leaves may be stored in the buffer solution for up to twenty-four hours, although preferably not more than five hours. While such storage is not necessary, it was found to help improve ultimate protein recovery.
[0036] An industrial filter may then be used to filter out the fibrous leaf biomass, leaving a green juice containing the soluble protein. We have found a screw press to give effective results. This green juice contains the soluble proteins along with plant chloroplast materials. Subjecting this green juice to powerful centrifuge will remove this chloroplast material, leaving an “amber juice” which contains the soluble proteins. Centrifuging at a force of approximately 12,000 g for approximately 20 minutes is sufficient to remove leaf chloroplast materials. Either continuous centrifuge or disk centrifuge is suitable. However, failure to adequately centrifuge the green juice will result in incomplete removal of the chloroplasts, and can leave an undesirable green tint in the resulting proteins.
[0037] Depending upon the desired use, it is possible to obtain several different protein products from this amber juice.
[0038] Product 1—Crude Protein Powder. The simplest approach is to prepare a protein powder product from this resulting amber juice through the use of standard industrial drying processes. This powder product can be prepared using spray drying, vacuum drying or freeze drying. However, spray drying is most practical for scale-up to an industrial level. This crude protein powder could be satisfactory for many commercial uses.
[0039] Product 2—Purified Protein Powder. It is possible to remove nucleic acids and small molecule impurities through a precipitation of the amber juice solution at its isoelectric point, which we have found to be at or about pH 5.3 (±0.5). The resulting solution can then be dried via spray drying or other industrial drying techniques to obtain a more highly purified powder product.
[0040] Product 3—It is possible to separate ribulose 1.5-bisphosphate carboxylase/oxygenase (RuBisCO) from the amber juice. An isoelectric point precipitation can be conducted at a pH of approximately 5.3 (±0.5), which is the isoelectric point for RuBisCO. This protein can then be centrifuged at a force of approximately 12,000 g or greater. The precipitate is then resuspended in buffer solution at a pH of approximately 7.77. The precipitate is then dried using spray drying or other means to produce a powder product containing RuBisCO. RuBisCO can be further purified if desired.
[0041] Product 4—The supernatant from the isoelectric point precipitation at pH 5.3 can be further purified to yield other leaf proteins. A second isoelectric point precipitation can be conducted involving the supernatant at a pH of approximately 4.2 (±0.5). The proteins can then be resuspended in buffer at a pH of approximately 7.77, and then dried using spray drying or other forms of drying.
[0042] Any of the above-described leaf protein powders may be used in the practice of the present invention.
[0043] The leaf protein powder is then placed in a suitable solvent, such as water, to form a suspension. Failure to place the protein powder into a suitable solvent may inhibit or prevent formation of an effective protein complex, as the dry protein is generally too coarse to efficiently bind or form a complex with a target substance. Additionally, preparing this protein-containing suspension is believed to expose additional binding sites to the target substance. In a preferred embodiment, water is used as the solvent to form the leaf protein aqueous suspension. In a particularly preferred embodiment, the ratio of leaf protein powder to water will be approximately 1 gram of leaf protein powder to between approximately 30 to 80 ml of water. Failure to maintain adequate water content will reduce the capacity of leaf protein to form a complex with the target substance. Use of excessive water content may add drying time and cost, and may reduce interaction of the protein and target substance.
[0044] In a preferred embodiment, the pH of the water is adjusted to between 3.3 and 6.3. Using a pH below this range may degrade the leaf protein. Using a pH in the preferred range maintains the structure of the protein, which optimizes its ability to retain the target substance.
[0045] In the present invention, the leaf protein forms a complex with one or more target substances in solution. The target substance(s), which is a lipid-soluble material, is solubilized in a suitable organic solvent, such as ethanol, methanol, other alcohols, hexane, acetone, or toluene, amongst many others. One skilled in the art will realize that the optimal organic solvent will depend on the nature of the lipid-soluble material. As an example, ethanol is particularly preferred if vitamin D 3 is the target substance.
[0046] Following solubilization of the target substance(s), the protein-containing suspension and the target-substance(s)-containing solution are then mixed together and then, in a preferred embodiment, frozen. Several techniques known to practitioners in the art may optionally be used to enhance mixing, for example, magnetic stirring, sonication, vortexing, or a combination of mixing methods. Practitioners in the art will recognize that different mixing techniques may prove more suitable for particular lipid-soluble materials than other techniques. If vitamin D 3 is the target substance, a preferred embodiment is the use of magnetic stirring for approximately five minutes.
[0047] In a preferred embodiment, freezing should occur within one hour after the protein-containing suspension is mixed with the target-substance-containing solution. In a more preferred embodiment, freezing occurs substantially immediately after the protein-containing suspension is mixed with the target-substance-containing solution. Delays in freezing after mixing the protein-containing suspension with the target-substance-containing solution may reduce the amount of the target substance which forms a complex with the leaf protein. At the time of mixture, the protein and target substance are in close contact. However, they may separate as time is allowed to pass. One skilled in the art will recognize that the rate at which the protein and target substance dissociate will depend on the nature of the target substance(s), and that this will affect the optimal time for freezing to occur.
[0048] Any techniques which obtain substantially immediate freezing of the protein-target substance mixture are potentially suitable. A non-limiting list of suitable freezing techniques include use of liquid nitrogen, dry ice or methanol. A preferred embodiment is the use of liquid nitrogen for freezing.
[0049] In a preferred embodiment, following freezing, the frozen mixture of protein and the target substance(s) is then dried. Any technique for drying may be suitable, including but not limited to freeze-drying, precipitation, oven-drying, microwaving or a combination of methods. One preferred embodiment is freeze-drying, as this technique will not degrade the protein or target substance. If freeze-drying is used, then the end product will be a powdery material containing a complex which contains leaf protein and the target substance.
[0050] The resulting dried complex, containing leaf protein and the lipid-soluble target substance(s), is suitable for use as a food additive, in forming nutrient, vitamin or other dietary supplements or nutraceuticals. Such products can be in any form known in the art, including but not limited to, tablets (including chewable tablets), capsules, gel-caps, powders, elixirs, and effervescent tablets. Alternatively, such products can be in the form of shakes, juices or other drinks, and bars.
[0051] The present invention also provides food compositions comprising complexes of leaf protein and lipophilic nutrients. Preferably the lipophilic nutrients are vitamin A, vitamin D, vitamin E, vitamin K 1 , cholesterol, carotenoids, conjugated linoleic acid, essential fatty acids, and other fatty acids. Because of its excellent nutritional qualities and water-solubility, leaf protein is highly suitable as a suitable carrier for lipophilic nutrients in food compositions. Complexes of leaf proteins and lipophilic nutrients are also useful for fortifying infant formulas with DHA and other lipid-soluble substances.
[0052] The food compositions of the present invention are formed by combining a leaf protein-lipid-soluble material complex according to the present invention with other food ingredients. Alternately stated, a food composition is a food product containing a leaf protein-lipid-soluble material complex of the present invention as an ingredient or component. A food composition can be a liquid or a solid food for human or animal consumption, and includes, but is not limited to, dairy products, processed meats, breads, cakes and other bakery products, processed fruits and vegetables, etc.
[0053] The present invention also includes compositions comprising a leaf protein-lipid soluble material complex, in which the leaf protein forms a complex with a lipophilic drug for delivery into humans or animals. Such compositions can be in any form known in the art, including but not limited to, tablets (including chewable tablets), capsules, gel-caps, powders, elixirs, and effervescent tablets. A non-limiting list of lipophilic drug substances which may used to form a leaf-protein-lipid-soluble material complex according to the present invention includes the following: Analgesics and anti-inflammatory agents: aloxiprin, auranofin, azapropazone, benorylate, diflunisal, etodolac, fenbufen, fenoprofen calcim, flurbiprofen, ibuprofen, indomethacin, ketoprofen, meclofenamic acid, mefenamic acid, nabumetone, naproxen, oxyphenbutazone, phenylbutazone, piroxicam, sulindac; Anthelmintics: albendazole, bephenium hydroxynaphthoate, cambendazole, dichlorophen, ivermectin, mebendazole, oxamniquine, oxfendazole, oxantel embonate, praziquantel, pyrantel embonate, thiabendazole; Anti-arrhythmic agents: amiodarone, disopyramide, flecamide acetate, quinidine sulphate; Anti-bacterial agents: benethamine penicillin, cinoxacin, ciprofloxacin, clarithromycin, clofazimine, cloxacillin, demeclocycline, doxycycline, erythromycin, ethionamide, imipenem, nalidixic acid, nitrofurantoin, rifampicin, spiramycin, sulphabenzamide, sulphadoxine, sulphamerazine, sulphacetamide, sulphadiazine, sulphafurazole, sulphamethoxazole, sulphapyridine, tetracycline, trimethoprim; Anti-coagulants: dicoumarol, dipyridamole, nicoumalone, phenindione; Anti-depressants: amoxapine, maprotiline, mianserin, nortriptyline, trazodone, trimipramine maleate; Anti-diabetics: acetohexamide, chlorpropamide, glibenclamide, gliclazide, glipizide, tolazamide, tolbutamide; Anti-epileptics: beclamide, carbamazepine, clonazepam, ethotoin, methoin, methsuximide, methylphenobarbitone, oxcarbazepine, paramethadione, phenacemide, phenobarbitone, phenyloin, phensuximide, primidone, sulthiame, valproic acid; Anti-fungal agents: amphotericin, butoconazole nitrate, clotrimazole, econazole nitrate, fluconazole, flucytosine, griseofulvin, itraconazole, ketoconazole, miconazole, natamycin, nystatin, sulconazole nitrate, terbinafine, terconazole, tioconazole, undecenoic acid; Anti-gout agents: allopurinol, probenecid, sulphin-pyrazone;] Anti-hypertensive agents: amlodipine, benidipine, darodipine, dilitazem, diazoxide, felodipine, guanabenz acetate, isradipine, minoxidil, nicardipine, nifedipine, nimodipine, phenoxybenzamine, prazosin, reserpine, terazosin; Anti-malarials: amodiaquine, chloroquine, chlorproguanil, halofantrine, mefloquine, proguanil, pyrimethamine, quinine sulphate; Anti-migraine agents: dihydroergotamine mesylate, ergotamine tartrate, methysergide maleate, pizotifen maleate, sumatriptan succinate; Anti-muscarinic agents: atropine, benzhexyl, biperiden, ethopropazine, hyoscyamine, mepenzolate bromide, oxyphencylcimine, tropicamide; Anti-neoplastic agents and Immunosuppressants: aminoglutethimide, amsacrine, azathioprine, busulphan, chlorambucil, cyclosporin, dacarbazine, estramustine, etoposide, lomustine, melphalan, mercaptopurine, methotrexate, mitomycin, mitotane, mitozantrone, procarbazine, tamoxifen citrate, testolactone. tacrolimus, sirolimus; Anti-protozoal agents: benznidazole, clioquinol, decoquinate, diiodohydroxyquinoline, diloxanide furoate, dinitolmide, furzolidone, metronidazole, nimorazole, nitrofurazone, omidazole, timidazole; Anti-thyroid agents: carbimazole, propylthiouracil; Alixiolytic, sedatives, hypnotics and neuroleptics: alprazolam, amylobarbitone, barbitone, bentazepam, bromazepam, bromperidol, brotizolam, butobarbitone, carbromal, chiordiazepoxide, chlormethiazole, chlorpromazine, clobazam, clotiazepam, clozapine, diazepam, droperidol, ethinamate, flunanisone, flunitrazepam, fluopromazine, flupenthixol decanoate, fluphenazine decanoate, flurazepam, baloperidol, lorazepam, lormetazepam, medazepam, meprobamate, methaqualone, midazolam, nitrazepam, oxazepam, pentobarbitone, perphenazine pimozide, prochlorperazine, sulpiride, temazepam, thioridazine, triazolam, zopiclone; beta-Blockers: acebutolol, alprenolol, atenolol, labetalol, metoprolol, nadolol, oxprenolol, pindolol, propranolol; Cardiac Inotropic agents: amrinone, digitoxin, digoxin, enoximone, lanatoside C, medigoxin; Corticosteroids: beclomethasone, betamethasone, budesonide, cortisone acetate, desoxymethasone, dexamethasone, fludrocortisone acetate, flunisolide, flucortolone, fluticasone propionate, hydrocortisone, methylprednisolone, prednisolone, prednisone, triamcinolone; Diuretics: acetazolamide, amiloride, bendrofluazide, bumetanide, chlorothiazide, chlorthalidone, ethacrynic acid, frusemide, metolazone, spironolactone, triamterene; Anti-parkinsonian agents: bromocriptine mesylate, lysuride maleate; Gastro-intestinal agents: bisacodyl, cimetidine, cisapride, diphenoxylate, domperidone, famotidine, loperamide, mesalazine, nizatidine, omeprazole, ondansetron, ranitidine, sulphasalazine; Histamine H-Receptor Antagonists: acrivastine, astemizole, cinnarizine, cyclizine, cyproheptadine, dimenhydrinate, flunarizine, loratadine, meclozine, oxatomide, terfenadine; Lipid regulating agents: bezafibrate, clofibrate, fenofibrate, gemfibrozil, probucol; Nitrates and other anti-anginal agents: amyl nitrate, glyceryl trinitrate, isosorbide dinitrate, isosorbide mononitrate, pentaerythritol tetranitrate; HIV protease inhibitors: Nelfinavir; Opioid analgesics: codeine, dextropropyoxyphene, diamorphine, dihydrocodeine, meptazinol, methadone, morphine, nalbuphine, pentazocine; Sex hormones: clomiphene citrate, danazol, ethinyl estradiol, medroxyprogesterone acetate, mestranol, methyltestosterone, norethisterone, norgestrel, estradiol, conjugated oestrogens, progesterone, stanozolol, stibestrol, testosterone, tibolone; Stimulants: amphetamine, dexamphetamine, dexfenfluramine, fenfluramine, and mazindol. (See Benita et al., 2007 regarding a list of lipophilic drugs).
[0054] The present invention also includes compositions for use in personal care and/or hygiene comprising the leaf protein-lipid-soluble material complexes disclosed herein (e.g., soaps, skin creams, soaps, cleansers, shampoos). Topical compositions containing complexes of leaf protein with vitamin E, vitamin A, conjugated linoleic acid, and essential fatty acids are preferred. The topical compositions disclosed herein are suitable for topical application to mammalian skin. The compositions comprise a safe and effective amount of the leaf protein complexes and other active agents, and a cosmetically- and/or pharmaceutically-acceptable topical carrier.
[0055] The phrase “cosmetically- and/or pharmaceutically-acceptable carrier”, as used herein, means any substantially non-toxic carrier suitable for topical administration to the skin, which generally has good aesthetic properties, and is compatible with the leaf protein-lipid-soluble material complexes of the present invention. By “compatible” it is meant that the leaf protein-lipid-soluble material complexes will remain stable and retain substantial activity therein. The carrier can be in a wide variety of forms, such as sprays, emulsions, mousses, liquids, creams, oils, lotions, ointments, gels and solids. Suitable pharmaceutically-acceptable topical carriers include, but are not limited to, water, glycerol, alcohol, propylene glycol, fatty alcohols, triglycerides, fatty acid esters, and mineral oils. Suitable topical cosmetically-acceptable carriers include, but are not limited to, water, petroleum jelly, petrolatum, mineral oil, vegetable oil, animal oil, organic and inorganic waxes, such as microcrystalline, paraffin and ozocerite wax, natural polymers, such as xanthanes, gelatin, cellulose, collagen, starch or gum arabic, synthetic polymers, alcohols, polyols, and the like. Preferably, because of its non-toxic topical properties, the pharmaceutically- and/or cosmetically-acceptable carrier is substantially miscible in water. Such water miscible carrier compositions can also include sustained or delayed release carriers, such as liposomes, microsponges, microspheres or microcapsules, aqueous based ointments, water-in-oil or oil-in-water emulsions, gels and the like.
[0056] The disclosed complex is also suitable as a component of tissue culture media or microbial growth media to promote growth, differentiation and/or viability of cultured cells. Milk proteins have been shown to be a suitable fatty acid carrier in cell culture (Swaisgood et al., 2001), and therefore leaf proteins should be similarly suitable.
EXAMPLES
Example 1
[0057] Evaluation of Different Strategies for Solubilizing Leaf Protein.
[0058] The purpose of this test was to evaluate different strategies for solubilizing the leaf protein. It is necessary to solubilize the leaf protein in order to remove residual pigments, fat content and other form a complex with the target lipid-soluble molecules.
[0059] Protein samples were subjected to solvent extraction with three organic solvents; hexane; acetone and methanol. Leaf protein powder prepared by the method of Lo et al. (2008) and Fu et al. (2010) has a water solubility value of 10.08±0.15 grams/liter (g/l). Hexane extraction of the protein powder yielded only a marginal increase in solubility of 10.82 g/l, whereas acetone extraction showed even smaller increase in solubility and methanol actually caused solubility to decrease. Based on these findings, the inventors did not utilize a solvent as pretreatment prior to mixing with vitamin D.
Example 2
[0060] Effect of Water Content on Leaf Protein-Lipophile Complex
[0061] Leaf protein samples were derived from Maryland tobacco variety 609LA, a low-alkaloid variety containing 0.6 mg/g to 0.8 mg/g of nicotine, using the method described in Lo, et al. (2008) and Fu et al. (2010). One gram of leaf protein powder was placed in a 300-ml freeze-drying glass flask (F05657000, Thermoscientific, Pittsburgh, Pa.), followed by addition of either 20 ml or 40 ml of water and 4 ml of vitamin D 3 in 99% pure ethanol (1000 ug/ml). The pH of the mixture was adjusted to pH 4.3 by gradually adding 1 M sodium hydroxide solution to the protein water solution prior to adding vitamin D 3 . This mixture was then magnetically stirred for 4 minutes before liquid nitrogen was added. Approximately 250 ml of liquid nitrogen was poured into the glass until the mixture appeared completely solid. The flask was then immediately closed with the lid and carefully placed in a thermally insulated bag filled with dry ice. The connector end of the freeze-drying flask was connected to the freeze-dryer (RVT4104 model Refrigerated Vapor Trap, Thermo Electron Corporation, NY) at −110° for 96 hours.
[0062] Using 40 ml of water per gram of leaf protein powder to obtain the vitamin D-protein complex, the inventors obtained a vitamin D 3 recovery of 84.68±3.92% of the total vitamin D 3 added. In contrast, use of only 20 ml of water per gram of protein powder significantly reduced the vitamin D 3 recovery to 70.21±8.92%. (See FIG. 2 ). The inventors observed that the spherical structure in the protein aggregates could not be maintained at the lower water content levels. Without wishing to be bound by theory, the inventors hypothesize that the increased water level at 40 ml helped form hydrogen bonds which maintained the protein structure. Conversely, at the lower water content level (which corresponded with higher protein density), self-stabilization of proteins may have taken place where proteins tended to form bonds which interconnected adjacent proteins, reducing the sites available for vitamin D 3 binding as well as limited surface area of ice-/water interface during the freeze-drying process.
Example 3
[0063] Effect of pH on Leaf Protein—Lipophile Complex
[0064] The inventors measured the effect of pH on the leaf protein—lipophile complex. They used the same preparation as described above in Example 2, except that they only used one water content level: one gram of leaf protein per 40 ml of water. They also prepared the leaf protein-vitamin D mixture described in Example 2 at three different pH levels (4.3, 8.5 and 11.0). As noted above, for pH adjustment, 1 M sodium hydroxide solution was gradually added to the protein water solution prior to adding vitamin D 3 .
[0065] The sample tested at pH 4.3 showed substantially higher recovery of vitamin D 3 (84.6%±3.92%, w/w) than either of the two other treatments. (See FIG. 3 ). There was also a slight increase in the water solubility of the vitamin D-protein complex at pH 4.3 from 10.08 to 10.78 g/l (See FIG. 4 ).
[0066] In each of the three treatments, the crude protein represented about 30% of the vitamin D 3 -tobacco leaf protein complex.
[0067] It is generally recognized that changes in pH can induce significant alterations in protein structure. At pH 4.3, the vitamin D3 -protein complex appeared to be spherical aggregates. As the pH increased to 8.5, the spherical structure opened up and bridged with adjacent aggregates, forming an interwoven structure. At pH 11.0, the spherical structure was completely disrupted, forming a continuous porous structure. In other words, porosity increased as the pH increased, corresponding to the loss of vitamin D. Without wishing to be bound by theory, the inventors believe that this increase in porosity was related to a loss of vitamin D. Again without wishing to be bound by theory, the inventors believe that that the lower porosity and spherical aggregate structure of the protein at the lower pH permitted the protein to retain or “trap” the vitamin D so it could not escape.
Example 4
[0068] Effect of Protein-Vitamin Mixing Technique on Vitamin Carrying Capacity
[0069] This test measured the effect of different techniques for mixing protein and vitamin D 3 on the protein's vitamin D 3 carrying capacity. They used the same preparation as described above in Example 2, except that they only used one water content level: one gram of leaf protein per 40 ml of water. The inventors also tested three mixing treatments: (i) magnetic stirring for 5 minutes, (ii) a Sonicator (28H ultrasonic bath, Neytech, Bloomfield, Conn.) at a frequency of 47±3 khZ for 5 minutes; and (iii) a combination involving the sonication treatment followed by the stirring treatment.
[0070] The highest vitamin recovery was obtained when the samples were stir-mixed for 5 minutes, reaching 84.68%±3.92%, w/w (weight/weight). Sonication alone resulted in a substantial reduction in vitamin D 3 recovery 62.53%±3.68%, w/w. The temperature increased by 20° C. following sonication. Without wishing to be bound by theory, the inventors hypothesize that the sharp change in temperature may have caused degradation of vitamin D 3 . Vitamin D 3 recovery was lowest when the samples were treated by both sonication and mixing (56.32±5.11%, w/w), likely due to the exposure of vitamin D 3 under elevated temperature for an extension of 5 minutes during the mixing process. (See FIG. 5 ). The crude protein content remained statistically the same in all three differentially mixed formulations.
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[0075] Forrest, S., R. Yada, D. Rousseau (2005), “Interactions of vitamin D 3 with bovine β-lactoglobulin A and β-casein.” Journal of Agricultural and Food Chemistry 53: 8003-8009.
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[0101] All publications, patents and patent applications mentioned in this specification are indicative of the level of skill of those skilled in the art to which this invention pertains, and are herein incorporated by reference to the same extent as if each individual publication, patent or patent application was specifically and individually indicated to be incorporated by reference.
[0102] Modifications may be made without departing from the basic spirit of the present invention. Accordingly, it will be appreciated by those skilled in the art that within the scope of the appended claims, the invention may be practiced other than has been specifically described herein. | This invention describes a novel composition of matter describing a complex comprising leaf protein and a lipophilic substance(s), along with the method of producing it. Delivery of lipid-soluble materials into the body is challenging because they are generally highly insoluble in water and very subject to oxidative degradation. The inventors have found that leaf protein—the water-soluble proteins derived from plant leaves—can efficiently form a complex with lipophilic materials. This leaf protein-lipid-soluble material complex is an effective carrier of lipophilic substances. As such, the leaf protein-lipid-soluble material complex disclosed herein can be used for the delivery of lipophilic vitamins, fatty acids, caretenoids, lipophilic drugs, and other lipophilic materials. This complex can be used to deliver lipophiles in foods, nutritional and dietary supplements, topical compositions and in pharmaceutical products. | 0 |
[0001] This application claims priority from applicant's U.S. Provisional Patent Application No. 61/459,687, filed on Dec. 17, 2010.
[0002] A foil, utilized such as an airfoil or hydrofoil, characterized by a duct moving relative to a mass of fluid. A constriction within the duct increases the speed of the fluid flowing within the duct and thereby produces a pressure drop inducing a mass of fluid external to the duct to accelerate into the duct. The acceleration of the fluid into the duct generates a resultant force, which can be varied and controlled to improve performance and reduce drag.
CROSS-REFERENCE TO RELATED APPLICATIONS
[0003] Not Applicable
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0004] Not Applicable
DESCRIPTION OF ATTACHED APPENDIX
[0005] Not Applicable
BACKGROUND OF THE INVENTION
[0006] The present invention is in the technical field of fluid movement and performance, more particularly, to foils. It is applicable more particularly, but not exclusively, to the production of the fixed wing of an aircraft. However, the invention may also be applied to the production of the wing of an aircraft with rotary wings. The invention may also be applied to the production of the impellers, turbines, sails, and propellers.
[0007] When a foil is moved relative to a fluid the foil produces a force. A foil is a two-dimensional cross sectional shape, at some point in the span, of a section of a fluid moving device including the blade of a propeller, rotor, or turbine; or wing such as provided for aircraft or watercraft. Foil properties are used to calculate and design three-dimensional (3D) wing and blade properties. The term “foil” makes no distinction for the type of fluid (e.g., air, gases, liquids, plasma), even though sometimes referring to an “airfoil” or “hydrofoil”.
[0008] For over 100 years, the prior art has never completely understood the dynamics of a foil. Traditionally, several approaches and theories have been taken to design foils. While the prior art concedes that Newton's laws of motion and Bernoulli's Principle are applicable the prior art has never determined how to apply them for a direct analytical mathematical solution.
[0009] National Aeronautics and Space Administration (NASA), Glen Research Center, Bernoulli and Newton , http://www.grc.nasa.gov/WWW/K-12/airplane/bernnew.html, available on the Internet; is hereby incorporated by reference.
[0010] One theory in prior design, of foils, has relied on the assumption that the different velocities of the fluid movement over the camber of the chord of the upper surface of the foil and the lower surface of the foil creates differential pressures and theoretically causes a net force normal to the direction of higher to lower fluid pressure, (e.g., generally vertical for aircraft). This is sometimes referred to as the “equal transit time theory”.
[0011] The vector component of this total force, vertical and pointing parallel to the force of gravity (for cruising aircraft) is sometimes called “lift”.
[0012] But, the total force also produces an undesirable vector component, horizontal and parallel to the force of gravity (for cruising aircraft), sometimes called “induced drag”.
[0013] National Aeronautics and Space Administration (NASA), Glen Research Center, Incorrect Theory # 1 , Longer Path or Equal Transit Theory , http://www.grc.nasa.gov/WWW/K-12/airplane/wrong1.html, available on the Internet; is hereby incorporated by reference.
[0014] Another approach in prior design of foils has based the lift provided by the foil on the theoretical dynamic pressure induced by the “angle of attack” on the lower surface area of the foil with the fluid flow. This theory presupposes that only the lower surface produces lift. But, this net force produced by the dynamic pressure acting upon the pitched surface of the foil also produces an undesirable vector component, horizontal and parallel to the force of gravity (for cruising aircraft), sometimes called “profile drag”.
[0015] National Aeronautics and Space Administration (NASA), Glen Research Center, Incorrect Theory # 2 , Skipping Stone Theory , http://www.grc.nasa.gov/WWW/K-12/airplane/wrong2.html, available on the Internet; is hereby incorporated by reference.
[0016] Another theory is based on the idea that the airfoil upper surface is shaped to act as a nozzle, which accelerates the flow. Such a nozzle configuration is called a Venturi nozzle and it can be analyzed analytically to an exact solution. But an airfoil is not a Venturi nozzle. There is no phantom surface to produce the other half of the nozzle. NASA's experiments noted that the velocity gradually decreases as you move away from the airfoil eventually approaching the free stream velocity. This is not the velocity found along the centerline of a conventional nozzle, which is typically higher than the velocity along the wall.
[0017] National Aeronautics and Space Administration (NASA), Glen Research Center, Incorrect Theory # 3 , Venturi Theory, http://www.grc.nasa.gov/WWW/K-12/airplane/wrong3.html, available on the Internet; is hereby incorporated by reference.
[0018] Since the prior art has not derived a direct mathematical analytical solution, existing design methods, for conventional foils, involves collecting data from wind tunnel tests. This method tests the current foil subject but is inaccurate when attempts are made to extrapolate the test data to other foil configurations.
[0019] Generally, profile drag and the induced drag represent the largest contributions to the total foil drag. Traditional design has targeted a reduction in profile drag. Traditionally design approaches have had to compromise between profile drag and generally fixed induced drag in order to produce acceptable lift at preferred fluid characteristics and relative motion between the foil and the fluid.
[0020] A diligent search revealed no prior references disclosing a foil characterized by a duct moving relative to a mass of fluid with a constriction within the duct. While reducing the area of a duct to induce an external fluid to flow into to the duct is common to venturi nozzles this class would not apply to a foil characterized by a duct moving relative to a fluid.
[0021] There exists, therefore, a need for a foil that has improved performance and that can be analytically calculated to an exact solution.
BRIEF SUMMARY OF THE INVENTION
[0022] The meaning of “foil” as used by this inventor refers to the use and application of the foil of prior art and of the present invention rather than particular shape, appearance, or design of the prior art, since this inventor's foil shape, appearance, and design is novel and unique compared to foils of the prior art. The use of the term foil can also apply to a three-dimensional (3D) shape embodied by the two-dimensional (2D) cross sectional view of the foil of the present invention.
[0023] According to one aspect of the invention there is provided a foil, which forms a duct, to channel the flow of a fluid from an inlet to an outlet.
[0024] The invention is characterized by a duct with an actual physical top, bottom, and two sides which constrains the flow of fluid from the inlet to the outlet. This enclosed duct therefore completely circumvents the NASA, Glenn Research Center, Incorrect Theory # 3 , Venturi Theory , argument, “There is no phantom surface to produce the other half of the nozzle.” pursuant to reference:
[0025] National Aeronautics and Space Administration (NASA), Glen Research Center, Incorrect Theory # 3 , Venturi Theory . http://www.grc.nasa.gov/WWW/K-12/airplane/wrong3.html, available on the Internet; is hereby incorporated by reference.
[0026] According to another aspect of the invention, the contained flow of fluid within the duct is channeled to a constricted area in the duct. This constriction, in the duct, increases the speed of the fluid within this constriction to satisfy the law of conservation of mass. This increase in speed results in a reduction in the fluid pressure within the duct. This reduction in fluid pressure causes an additional mass of fluid to be accelerated into the duct through an external opening in the duct. This combination of mass (M) and acceleration (A) of external fluid thus applies a force (F) vector pursuant to Newton's classical equation of motion, F (force)=M (mass) times A (acceleration). In the present invention both the magnitude and directional components of any force vectors (F) can be beneficially designed, predicted, and controlled.
[0027] The directional component of this force vector (F) can be designed into the foil or adjusted independently, of the internal fluid flow through the foil and within the duct. The force vector (F) and be directed towards the preferred direction (e.g., lift, vertical and pointing up for cruising aircraft). Since the direction and magnitude components of force vector (F) are pointed in the preferred direction there is no component of the force vector (F) perpendicular to the desired direction of lift and induced drag is substantially reduced. Thus, the present invention provides a foil that improves performance by providing control of the magnitude and directional components of the force vector (F) in order to maximize the force of lift, in the preferred direction.
[0028] In the present invention profile drag is independent of induced drag. In the present invention profile drag caused by fluid flow over the external surface structure of the foil is also independent of the foil internal fluid flow which produces the desired force, sometimes called lift. The present invention provides an improved foil design that allows profile drag to be reduced without compromising the force of lift.
[0029] A three dimensional shape (e.g., blade of a propeller, rotor, or turbine, wing, sail) can be constructed from this two dimensional foil in varying combinations of rectangular, circular, or other shape to apply a preferred vector of force. (e.g., lift, rotation, stability, control).
[0030] 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 one of many possible embodiments of the invention.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0031] The drawings constitute a part of this specification and include exemplary embodiments to the invention, which may be embodied in various forms. It is to be understood that in some instances various aspects of the invention may be shown exaggerated, enlarged, or reduced to facilitate an understanding of the invention.
[0032] FIG. 1 is a two-dimensional (2D) right side view of the foil with the right side endplate in place and the outline of the foil behind the endplate shown as a dashed line
[0033] FIG. 2 is a two-dimensional (2D) right side view of the foil with the right side endplate removed for clarity
[0034] FIG. 3 is a perspective view of the foil depicted as a three-dimensional (3D) wing mounted on a conventional aircraft looking from the front of the aircraft into the intake of the foil.
[0035] FIG. 4 is a perspective view of the foil depicted as a three-dimensional (3D) wing mounted on a conventional aircraft looking from above the aircraft into the external opening of the foil.
[0036] FIG. 5 is a perspective view of the foil depicted as a three-dimensional (3D) wing mounted on a conventional aircraft looking from behind the aircraft into the outlet of the foil.
DETAILED DESCRIPTION OF THE INVENTION
[0037] A detailed description of one possible embodiment of the invention, a two-dimensional (2D) airfoil, sometimes depicted as a three-dimensional (3D) aircraft wing, is provided herein. It is to be understood, however, that the present invention may be embodied in various forms. Therefore, specific details disclosed herein are not to be interpreted as limiting, but rather as a basis for the claims and as a representative basis for teaching one skilled in the art to employ the present invention in virtually any appropriately detailed system, structure or manner.
[0038] A more complete understanding of the invention and many of the attendant advantages thereof will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein: analogous parts are identified by like reference numerals as follows:
100 Right endplate 101 Inlet 101 A Fluid flow into inlet 102 Constriction 102 B Combined fluid flow into constriction 103 External opening 103 C Fluid flow into external opening 104 Outlet 104 D Fluid flow from outlet 105 Direction of foil travel 106 Outline of foil hidden behind right endplate 112 Force vector exerted on foil near external opening 113 Force vector exerted on foil near outlet 114 Right side airfoil with the right side endplate removed 200 Right side airfoil with the right side endplate removed and linear slide valve and flap valve in their retracted positions 201 Right side airfoil with the right side endplate removed and linear slide valve and flap valve in their extended positions 202 Linear slide valve to vary external opening 203 Rotating flap valve to vary outlet configuration 204 Actuator to vary linear slide valve at external opening 205 Actuator to rotate valve flap at outlet 300 Foil depicted as a three-dimensional (3D) aircraft wing 400 Conventional aircraft attached to foil depicted as a three-dimensional (3D) aircraft wing
[0061] Similar to fixed aircraft wing, rotary aircraft wings, submerged marine propellers, aircraft propellers, airboat propellers, water craft sails, power generating turbines, gas compressors, fans, and pump impellers the present invention can be made in various sizes and configurations including, but not exclusively, with any size of intake, outlet, external opening, and length. It should be recognized that the present invention is not limited to the use in aircraft wings having the specific designs that are herein described for purposes of example.
[0062] Referring to FIG. 2 of the drawings, the embodiment of the present invention, as an airfoil 114 has an inlet 100 , external opening 103 , an outlet 104 , and a constriction 102 .
[0063] Referring jointly to FIG. 1 , FIG. 2 , FIG. 3 , FIG. 4 , FIG. 5 , FIG. 6 , and FIG. 7 the endplates typical of right endplate 100 of FIG. 1 constrain all the fluid flow from inlet 100 to outlet 104 of airfoil 114 . The endplates typical of right endplate 100 prevent fluid from escaping from the ends of a three-dimensional airfoil embodied as a wing on an aircraft 500 , 600 , and 700 .
[0064] The foil 114 of the present invention provides a duct for the fluid flow 101 A entering the foil 114 at the intake 101 to be channeled to a constriction 102 which increases the velocity of the fluid 102 B in the constriction 103 and thereby reduces the pressure of the fluid 102 B. This reduction in fluid pressure at the constriction 102 causes a flow of fluid 103 C to accelerate into the external opening 103 into the foil 114 .
[0065] The mass of external fluid 103 C accelerating into the foil 114 thus applies a force vector 112 .
[0066] The foil 114 of the present invention also provides an outlet 104 for the fluid flow 104 D exiting the foil 114 . The area of the outlet 104 is designed to control the speed of the fluid 104 D exiting the outlet 104 . The angle of the outlet 104 is designed to control the direction of the fluid 104 D exiting the outlet 104 .
[0067] The velocity vector components of speed and direction of the fluid flow 104 D determine the force vector 113 .
[0068] In this embodiment of the present invention as an airfoil both the magnitude and directional components of the force vectors 112 and 113 can be beneficially designed, predicted, and controlled pursuant to control of the fluid flows 103 C and 104 D. A three-dimensional (3D) shape (e.g., fixed aircraft wing, rotary aircraft wings, submerged marine propellers, aircraft propellers, airboat propellers, water craft sails, power generating turbines, gas compressors, fans, and pump impellers) can be constructed from the foil 114 of the present invention in varying combinations of rectangular, circular, or other shape to apply the preferred magnitude and directional components of the force vectors 112 and 113 (e.g., lift, rotation, stability, control).
[0069] In FIG. 5 of the drawings, the embodiment of the present invention, as an airfoil is depicted as being utilized as a wing 300 for a conventional aircraft 400 . The aircraft 500 is depicted looking from the front into the intake 101 of the foil.
[0070] In FIG. 6 of the drawings, the embodiment of the present invention, as an airfoil, is depicted as being utilized as a wing 300 for a conventional aircraft 400 . The aircraft 600 is depicted looking from above into the external opening 103 of the foil.
[0071] FIG. 7 illustrates the embodiment of the present invention, as an airfoil is depicted as being utilized as a wing 300 for a conventional aircraft 400 . The aircraft 700 is depicted looking from behind into the outlet 104 of the foil.
[0072] FIG. 2 and FIG. 3 illustrate an embodiment of the present invention, configured for variable configurations, 200 and 201 with valves 202 and 203 and actuators 204 and 205 designed to vary the fluid flows 103 C and 104 D. Varying the fluid flows 103 C and 104 D thus varies the force vectors 112 and 113 .
[0073] In FIG. 3 valves 202 and 203 and actuators 204 and 205 are in their retracted positions.
[0074] In FIG. 4 valves 202 and 203 and actuators 204 and 205 are in their extended positions thus changing the speed and directional components of force vectors 112 and 113 .
[0075] The elements embodied in FIG. 1 , FIG. 2 , FIG. 3 , FIG. 4 , FIG. 5 , FIG. 6 , and FIG. 7 configured for flow of lower density fluids, such as air, can be constructed by conventional manufacturing techniques. This includes, but is not limited to, assembling spars and ribs to create a sub-structure, and overlaying a skin over this sub-structure to provide an aerodynamic surface. State-of-the-art composite fabrication techniques can be used. The materials used in the construction of the embodiments represented by FIG. 1 , FIG. 2 , FIG. 3 , FIG. 4 , FIG. 5 , FIG. 6 , and FIG. 7 are similar to those typically used in the relevant industry (e.g., aerospace, automotive, wind turbines, watercraft). This includes, but is not limited to, metals, plastics, fabrics, and/or composite materials. In the case of sails, parachutes or other winged equipment the fabric membrane can be constructed so as to maintain its shape comprised of tensioning components such as wire or fabric line to hold the shape of the wing and using the pressure of fluid to keep the foil inflated to shape.
[0076] The elements and mechanism to rotate and move 202 and 203 can be constructed by conventional manufacturing techniques. This includes, but is not limited to, assembling spars and ribs to create a sub-structure, and overlaying a skin over this sub-structure to provide an aerodynamic surface. Typical metal “flat plate” fabrication techniques can also be applied. The materials used in the construction of the movable elements are similar to those typically used in the relevant industry (e.g., aerospace, automotive, wind turbines, watercraft). This includes, but is not limited to, metals, plastics, fabrics, and/or composite materials.
[0077] The elements of the foil configured for flow of medium to higher density fluids, such as water, can be constructed by conventional manufacturing techniques. This includes, but is not limited to, machine cutting and fabricating from metal or plastic or a combination of materials.
[0078] Rotating hinges and linear bearings where applicable are similar to those typically used in the relevant industry. Standard conventional actuating equipment such as electromechanical or fluid filled actuators for positioners 204 and 205 can be used to vary the position of 202 and 203 .
[0079] With the embodiments described above one skilled in the development of foils can devise specific shapes for the foil elements that will achieve the benefits of the invention. The foil, of the present invention, can also be used in any position or angle to provide a downward or horizontal force. The foil of the present invention can be used vertically as a “sail” on a watercraft, where the foil of the present invention would produce a horizontal force to propel the watercraft in a horizontal direction.)
[0080] While the foil depicted in FIG. 1 , FIG. 2 , FIG. 3 , FIG. 4 , FIG. 5 , FIG. 6 , and FIG. 7 has a specific configuration, it is not the only foil configuration operable with the present invention. As will be set out below, rather than the invention being specific foil configuration, it is the interaction of the fluids flows at the inlet, outlet, constriction, and external opening and their combined effect on the parameters of fluid flow that provides the benefits of the invention.
[0081] With the embodiment described above one skilled in the development of foils can devise specific shapes for the foil elements that will achieve the benefits of the invention.
[0082] The advantages of the present invention include, without limitation that it improves performance and efficiency. The resulting performance of a foil designed pursuant to the embodiments of the present invention are predictable and repeatable. The configuration of the foil of the present invention can be designed, adjusted and controlled to provide the preferred and predictable results.
[0083] While the invention has been described in connection with the embodiments illustrated above, it is not intended to limit the scope of the invention to the particular form set forth, but on the contrary, it is intended to cover such alternatives, modifications, and equivalents as may be included within the spirit and scope of the invention. It is recognized that various equivalents, alternatives and modifications are possible within the scope of the appended claims and their legal equivalents. While several forms of the invention have been shown and described in the above teachings, other forms will now be apparent to those skilled in the art. Therefore, it will be understood that the embodiments shown in the drawings and described above are merely for illustrative purposes, and are not intended to limit the scope of the invention which is defined by the claims which follow. | A foil, utilized such as an airfoil or hydrofoil, characterized by a duct moving relative to a mass of fluid. The duct channels the flow of the portion of the fluid through which the duct is moving. A constriction within the duct increases the speed of the fluid constrained within the duct and thereby produces a pressure drop. The pressure drop induces a mass of fluid external to the duct and approximately parallel to the duct to accelerate into the duct. The acceleration of the external fluid mass into the duct generates a resultant force vector, which can be utilized, varied, and controlled to improve performance and reduce drag. | 1 |
BACKGROUND OF THE INVENTION
[0001] The subject matter disclosed herein relates to gas turbines, and more specifically, to systems and methods for controlling fuel flow in fuel nozzles.
[0002] Gas turbine systems generally include a compressor, a combustor, and a turbine. The compressor compresses air from an air intake, and subsequently directs the compressed air to the combustor. In the combustor, the compressed air received from the compressor is mixed with a fuel and is combusted to create combustion gases. The combustion gases are directed into the turbine. In the turbine, the combustion gases pass across turbine blades of the turbine, thereby driving the turbine blades, and a shaft to which the turbine blades are attached, into rotation. The rotation of the shaft may further drive a load, such as an electrical generator, that is coupled to the shaft.
BRIEF DESCRIPTION OF THE INVENTION
[0003] Certain embodiments commensurate in scope with the originally claimed invention are summarized below. These embodiments are not intended to limit the scope of the claimed invention, but rather these embodiments are intended only to provide a brief summary of possible forms of the invention. Indeed, the invention may encompass a variety of forms that may be similar to or different from the embodiments set forth below.
[0004] In one embodiment, a system includes a fuel supply system. The fuel supply includes a primary fuel supply, a fuel additive supply, and a common pipeline coupled to the primary fuel and fuel additive supplies. The primary fuel supply includes a primary fuel having a first average molecular weight. The fuel additive includes a fuel additive having a second molecular weight that is greater than the first average molecular weight. The common pipeline is configured to direct a mixture of the primary fuel and the fuel additive into a fuel nozzle.
[0005] In a second embodiment, a gas turbine engine includes a compressor, a combustor, a fuel supply system, and a turbine. The compressor is configured to compress air. The combustor comprises at least one fuel nozzle and is configured to receive the air from the compressor and to combust the air and a fuel mixture to generate combustion products. The fuel supply system is configured to supply the fuel mixture to the at least one fuel nozzle. The fuel supply system includes a primary fuel supply, a fuel additive supply, and a common pipeline coupled to the primary fuel supply and the fuel additive supply. The primary fuel supply includes a primary fuel having a first average volumetric heating value. The fuel additive includes a fuel additive having a second average volumetric heating value that is greater than the first average volumetric heating value. The common pipeline is configured to mix the primary fuel and the fuel additive to form the fuel mixture and to direct the fuel mixture to the combustor. The turbine is configured to receive the combustion products from the combustor.
[0006] In a third embodiment, a method includes detecting an operating parameter related to combustion of air and a fuel mixture within a combustor, determining if the operating parameter is desirable using a sensor and a controller, and adjusting a flow rate of a fuel additive based on a measurement of the operating parameter. The fuel additive has a first volumetric heating value that is greater than an overall volumetric heating value of the fuel mixture. The fuel mixture includes a primary fuel and a fuel additive.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] These and other features, aspects, and advantages of the present invention 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:
[0008] FIG. 1 is a schematic diagram of an embodiment of a gas turbine system having a fuel supply system with features to improve flame stability;
[0009] FIG. 2 is a perspective view of an embodiment of fuel nozzles of the fuel supply system, illustrating an arrangement of the fuel nozzles within a combustor of the gas turbine system;
[0010] FIG. 3 is a block diagram of an embodiment of the fuel supply system of FIG. 1 , illustrating a fuel additive supply containing higher hydrocarbons (HHCs) and/or diluents to improve flame stability within the combustor;
[0011] FIG. 4 is a partial cross-sectional view of an embodiment of the fuel nozzle of FIG. 1 with a plurality of swirl vanes to mix fuel and air for delivery into the combustor;
[0012] FIG. 5 is a perspective view of an embodiment of the swirl vane of FIG. 4 ; and
[0013] FIG. 6 is a partial cross-sectional view of an embodiment of the fuel nozzle of FIG. 1 with a plurality of pilot tubes configured to mix fuel and air for delivery into the combustor.
DETAILED DESCRIPTION OF THE INVENTION
[0014] One or more specific embodiments of the present invention will be described below. In an effort to provide a concise description of these embodiments, all features of an actual implementation may not be described in the specification. It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions must be made to achieve the developers' specific goals, such as compliance with system-related and business-related constraints, which may vary from one implementation to another. Moreover, it should be appreciated that such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure.
[0015] When introducing elements of various embodiments of the present invention, the articles “a,” “an,” “the,” and “said” are intended to mean that there are one or more of the elements. The terms “comprising,” “including,” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements.
[0016] By way of introduction, a distinction should be drawn between the terms “energy output” and “energy density”. The term “energy output” may refer to a rate of energy produced by combustion of a fuel. Accordingly, the energy output of a system may be increased by increasing a flow rate of the fuel. On the other hand, the terms “energy density” and “heating value” refer to intensive properties of the fuel. The energy density may be volumetric (i.e., energy produced per unit volume), molar (i.e., energy produced per mole of substance), or have another suitable basis. Notably, changing the flow rate of the fuel may have no impact on its energy density.
[0017] The present disclosure is directed toward systems and methods to improve flame stability within combustors of gas turbine systems. In particular, a fuel additive may be added to a primary fuel to form a fuel mixture, and the fuel mixture may then be directed to the combustor for combustion. The composition of the fuel mixture may be varied in order to adjust certain properties (e.g., energy density or heating value) of the fuel, which, in turn, may adjust the pressure, temperature, length, volume, flame front shape, or another parameter of the combustion flame. In certain embodiments, the fuel additive includes a higher hydrocarbon (HHC) with a higher molecular weight, density, and/or volumetric energy density than the primary fuel. For example, the primary fuel may be mostly methane, and the fuel additive may include ethane, propane, or butane.
[0018] As will be appreciated, the primary fuel is often a mixture of several components, such as hydrocarbons (e.g., alkanes), sulfur (e.g., thiols), and/or nitrogen (e.g., amines). These components define average properties (e.g., molecular weight, energy density, etc.) of the primary fuel. The primary fuel is typically not homogenous, and the average properties may change over time, often unpredictably. Unfortunately, these unpredictable changes result in combustion instabilities within the gas turbine system. For example, the energy density (e.g., heating value) of the primary fuel may decrease, resulting in fluctuations in flame temperature, flame pressure, and flame volume. Thus, it is now recognized that the addition of a fuel additive may help reduce these fluctuations within the primary fuel. In other words, the fuel additive can help change the average energy density, molecular weight, volumetric flow rate, and other properties of the primary fuel. In this manner, the fuel properties can help stabilize the flame, thereby reducing combustion dynamics and increasing the efficiency of the gas turbine system.
[0019] Turning now to the figures, FIG. 1 illustrates a block diagram of an embodiment of a gas turbine system 10 having a fuel supply system 11 with features to improve the operability of the gas turbine system 10 . For example, the fuel supply system 11 may supply at least one fuel additive (e.g., one or more HHCs) for stabilizing a flame within the gas turbine system 10 . In the illustrated embodiment, the fuel supply system 11 includes a fuel manifold 12 , which may route or flow a primary fuel and one or more fuel additives. Throughout the discussion, a set of axes will be referenced. These axes are based on a cylindrical coordinate system and point in an axial direction 14 , a radial direction 16 , and a circumferential direction 18 . For example, the axial direction 14 extends along a longitudinal axis 20 of the gas turbine system 10 , the radial direction 16 extends away from the longitudinal axis 20 , and the circumferential direction 18 extends around the longitudinal axis 20 .
[0020] As illustrated, the gas turbine system 10 includes a compressor 22 , a combustor 24 , and a turbine 26 . The compressor 22 receives air 28 from an intake 30 and compresses the air 28 for delivery to the combustor 24 . A portion of the air 28 is routed to a fuel nozzle 32 , where the air 28 may premix with a fuel (e.g., a fuel mixture) 34 before entering the combustion zone. As shown, the fuel 34 is supplied by the fuel manifold 12 . The fuel manifold 12 may also supply a fuel additive (e.g., one or more HHCs) to adjust the composition of the fuel 34 . As noted earlier, the composition of the fuel 34 may be adjusted in order to improve the stability of the flame within the combustor 24 .
[0021] The air 28 and the fuel 34 are fed to the combustor 24 at a ratio suitable for combustion, emissions, power output, and the like. The mixture of the air 28 and the fuel mixture 34 is subsequently combusted in the combustor 24 , thereby producing hot combustion products. The hot combustion products enter the turbine 26 and force blades 36 of the turbine 26 to rotate, thereby driving a shaft 38 of the gas turbine system 10 into rotation. The rotating shaft 38 provides the energy for the compressor 22 to compress the air 28 . More specifically, the rotating shaft 38 further rotates compressor blades 39 attached to the shaft 38 within the compressor 22 , thereby compressing the air 28 that is fed into the compressor 22 . In addition, the rotating shaft 38 may rotate a load 40 , such as an electrical generator or any device capable of utilizing the mechanical energy of the shaft 38 . After the turbine 26 extracts useful work from the combustion products, the combustion products are discharged to an exhaust 42 .
[0022] As noted previously, the fuel supply system 11 supplies a fuel additive to one or more fuel nozzles 32 in order to improve combustion stability. FIG. 2 illustrates an arrangement of the fuel nozzles 32 within the combustor 24 of the gas turbine system 10 . As shown, six fuel nozzles 32 are mounted to a head end 44 of the combustor 24 . However, in other embodiments, the number of fuel nozzles 32 may vary. For example, the gas turbine system 10 may include 1, 2, 3, 4, 5, 10, 50, 100, or more fuel nozzles 32 .
[0023] As illustrated, the six fuel nozzles 32 are disposed in a concentric arrangement. That is, five fuel nozzles 32 (e.g., outer fuel nozzles 46 ) are disposed about a central fuel nozzle 48 . As will be appreciated, the arrangement of the fuel nozzles 32 on the head end 44 may vary. For example, the fuel nozzles 32 may be disposed in a circular arrangement, in a linear arrangement, or in any other suitable arrangement.
[0024] In certain embodiments, the fuel supply system 11 may supply the fuel additive to a certain subset of the fuel nozzles 32 . For example, the central fuel nozzle 48 (e.g., pilot fuel nozzle) generally may have a greater influence on combustion dynamics, and it may be desirable to supply the fuel additive to the central fuel nozzle 48 . However, certain embodiments of the fuel supply system 11 may supply the fuel additive to all of the fuel nozzles 32 . In addition, the fuel supply system 11 may supply a similar or different HHC to each of the fuel nozzles 32 . The components of the fuel supply system 11 are discussed below with respect to FIG. 3 .
[0025] FIG. 3 illustrates a block diagram of an embodiment of the fuel supply system 11 . The fuel supply system 11 includes a primary fuel supply 50 and a fuel additive (e.g., HHC) supply 52 coupled together by a common pipe 54 . That is, the primary fuel 50 and the HHC 52 combine to form the fuel mixture 34 that is directed to the fuel nozzles 32 . The HHC 52 may be supplied from storage tanks coupled to the fuel supply system 11 . As noted earlier, the fuel additive 52 may be any fuel having a greater molecular weight, density, and/or energy density than the primary fuel 50 . For example, the primary fuel 50 may include methane, and the HHC 52 may include ethane, propane, butane, another alkane, an alkene, alkyne, or any other suitable hydrocarbon. It should be noted that the HHC 52 is often a mixture of various components, and may include hydrocarbons, thiols, amines, and the like. In certain embodiments, the HHC 52 may include any species with more than one carbon molecule (e.g., C 1 +). The HHC 52 may have at least, on average, 1, 2, 3, 4, 5, or more carbon atoms per molecule than the primary fuel 50 . Certain HHCs 52 have a higher heating value (HHV) in the range of 1500 to 11000 BTU/cubic foot.
[0026] The combustor 24 may be designed to combust the fuel mixture 34 to produce a specific total energy output. As noted earlier, the energy density of the primary fuel 50 may vary, which results in a variable total energy output. In order to stabilize and maintain the total energy output, the flow rate and/or the composition of the fuel mixture 34 may be varied. As will be appreciated, stabilization of the energy output may improve the operability and efficiency of the gas turbine system 10 .
[0027] The flow rate of the fuel mixture 34 can be increased or decreased by adding a diluent 56 and/or the HHC 52 to achieve a desired total heat output. In order to maintain an approximately constant total heat output, the HHC 52 may be used to increase the energy density of the fuel mixture 34 , thereby reducing the total flow rate of the fuel mixture 34 . Depending on the desired total energy output, the flow rate of the HHC 52 may be less than approximately 40, 30, or 20 percent of the total flow rate of the fuel mixture 34 by volume. However, in certain embodiments, it may be desirable to adjust the total energy output without changing the flow rate of the fuel mixture 34 .
[0028] In certain embodiments, the fuel nozzle 32 may operate using the primary fuel 50 without the HHC 52 until it is desired to adjust the energy density of the fuel mixture 34 . For example, the gas turbine system 10 may include a plurality of operating modes, such as a startup mode, a steady-state mode, a low load mode, a medium load mode, a high load mode, a transient mode, a shut-down mode, or any other mode, each having a controlled ratio of primary fuel 50 to the HHC 52 . For example, each of these modes may include a mixture of primary fuel 50 and 1, 2, 3, 4, 5, or more fuel additives 52 (i.e., HHCs). The primary fuel 50 and one or more fuel additives 52 may change for each mode, or they may be partially or entirely the same. Furthermore, the ratio among the primary fuel 50 and one or more fuel additives 52 may change from one mode to another.
[0029] It may also be desirable to increase the flow rate of the fuel mixture 34 without changing the total heat output. As shown, a diluent supply 56 is coupled to the common pipe 54 . The diluent 56 may be any material having a lower average molecular weight, density, and/or energy density than the primary fuel 50 . For example, the diluent may be steam, nitrogen, another inert gas, an alcohol, ketone, or any other suitable material. Thus, the addition of the diluents 56 into the primary fuel 50 decreases the energy density of the fuel mixture 34 . In a manner similar to the HHC 52 above, a flow rate of the primary fuel 50 may be decreased and a flow rate of the diluent 56 may be increased by a greater amount that impacts the pressure drop across the fuel nozzle 32 .
[0030] In order to adjust the flow rates of the primary fuel 50 , the HHC 52 , and the diluent 56 , control valves 58 , 60 , and 62 are disposed along their respective flow paths. The control valves 58 , 60 , and 62 are communicatively coupled to a controller 64 . As shown, the controller 64 includes a processor 66 and memory 68 to execute instructions to control the combustion dynamics by adjusting the control valves 58 , 60 , and 62 . These instructions may be encoded in software programs that may be executed by the processor 66 . Further, the instructions may be stored in a tangible, non-transitory, computer-readable medium, such as the memory 68 . The memory 68 may include, for example, random-access memory, read-only memory, hard drives, and the like. In certain embodiments, the controller 64 may execute instructions to control the ratio of the primary fuel 50 to the HHC 52 in each operating mode of the gas turbine system (e.g., startup mode, steady-state mode, etc.)
[0031] The combustion dynamics and flame stability are largely affected by the energy output and energy density of the fuel mixture 34 . However, the flame stability is affected by a myriad of other operating parameters, such as flame temperature, pressure fluctuations, flow rates, pressure drops, and the like. Accordingly, it is desirable to monitor certain operating parameters and adjust the flow rates of the primary fuel 50 , the fuel additive 52 , and/or the diluent 56 in response to the monitored operating parameters.
[0032] As shown, a sensor 70 is disposed upstream of the fuel nozzle 32 and another sensor 72 is disposed within or downstream of the fuel nozzle 32 . The sensors 70 and 72 monitor various operating conditions of the fuel supply system 11 and the fuel nozzle 32 , such as pressure, flow rates, pressure differentials, flame temperature, flame length, flame volume, and the like. The sensors 70 and 72 are communicatively coupled to the controller 64 , which may adjust the control valves 58 , 60 , and 62 based on the operating parameters detected by the sensors 70 and 72 . For example, the controller 64 may determine that an operating parameter is not desirable and may execute instructions to adjust the control valves 58 , 60 , 62 in order to adjust the operating parameter toward a desired range.
[0033] In certain embodiments, the sensors 70 and 72 may detect a pressure drop or differential across a portion of the fuel nozzle 32 . As noted earlier, the pressure differential may affect combustion dynamics, and thus, it is desirable to monitor and adjust the pressure differential. In a similar manner to adjusting the energy density of the fuel mixture 34 , the pressure differential across the fuel nozzle 32 may be varied by changing the composition of the fuel mixture 34 . Certain HHCs 52 have a greater heating value (i.e., energy per unit volume) than the primary fuel 50 . Thus, the HHC 52 and the primary fuel 50 may be mixed in certain ratios to reduce the flow rate of the fuel mixture 34 while maintaining an approximately constant total heat output. Lower flow rates typically have lower pressure drops through orifices, and thus, adding HHCs 52 to the fuel mixture 34 may decrease the pressure drop across the fuel nozzle 32 . Decreasing the pressure drop may be desirable, for example, to shift the heat release location and reduce combustion dynamics.
[0034] As noted earlier, changes in the operating conditions of the combustor 24 may result in combustion instabilities. Accordingly, it may be desirable to adjust the pressure differential across the fuel nozzle 32 , while maintaining an approximately constant energy output. For example, a flow rate of the HHC 52 may be increased while a flow rate of the primary fuel 50 is decreased, such that the additional energy output contributed by the HHC 52 is substantially offset by the decreased energy output contributed by the primary fuel 50 . In this manner, the resulting flow rate of the fuel mixture 34 is decreased and the density of the fuel mixture 34 is increased. As will be appreciated, the decreased flow rate may decrease the pressure drop across the fuel nozzle 32 . The increased density may have a positive effect on flame location or shape. In summary, the composition and/or flow rate of the fuel mixture 34 may be changed to adjust the pressure differential across the fuel nozzle 32 , while maintaining an approximately constant energy output.
[0035] The diluent 56 may be used in a similar manner to adjust the pressure differential across the fuel nozzle 32 . That is, the flow rate of the diluent 56 may be increased and the flow rate of the primary fuel 50 may be decreased, such that the total energy output of the fuel mixture 34 remains the same. Certain diluents 56 have a lower energy density than the primary fuel 50 . Thus, the diluents 56 and the primary fuel 50 may be mixed with various ratios to increase the flow rate of the fuel mixture 34 while maintaining an approximately constant total heat output. Higher flow rates typically have higher pressure drops through orifices, and thus, adding the diluents 56 to the fuel mixture 34 generally increases the pressure drop across the fuel nozzle 32 . In certain configurations, the flow rate of the diluent 56 may be increased while the flow rate of the primary fuel 50 is decreased or remains the same. As a result, the energy density of the fuel mixture 34 is decreased. As will be appreciated, in such a configuration, the net effect on the pressure drop helps to mitigate the combustion dynamics. Accordingly, the addition of the diluent 56 may be designed to increase the pressure drop across the fuel nozzle 32 , which may be desirable to improve the stability of the combustion flame.
[0036] The disclosed technique of holding one operating parameter constant while modifying another using the HHC 52 , the diluent 56 , or both, can be applied to various other operating parameters of the fuel nozzle 32 . For example, the pressure, energy density, flow rate, pressure drop, pressure drop, flame length, flame volume, and the like may be held constant while another parameter is simultaneously varied. In addition, the aforementioned operating parameters are given by way of example and are not intended to be limiting. That is, it may be desirable to adjust the flow rates of the primary fuel 50 , the HHC 52 , the diluent 56 , or any combination thereof to affect any other operating parameter related to combustion stability.
[0037] It should be noted that the fuel additive supply 52 and the diluent supply 56 may be used independently or in combination with each other. That is, certain embodiments of the fuel supply system 11 may include the fuel additive supply 52 but not the diluent supply 56 . In addition, the use of the fuel additive supply 52 or the diluent supply 56 may be based on the orientation of the fuel nozzles 32 about the head end 44 (see FIG. 2 ). For example, the central fuel nozzle 48 may have a greater impact on combustion dynamics and may benefit more from addition of the fuel additive 52 . On the other hand, it may be desirable to provide the outer fuel nozzles 44 with the diluent 56 in order to control the volume of the combustion flame.
[0038] It may be desirable to modify the fuel composition at different operating modes (e.g., startup, steady-state, partial load, full load, etc.) of the gas turbine system 10 . For example, each operating mode may have a different ratio of the HHC 52 to the primary fuel 50 . As will be appreciated, fuel gas compressors use a lower molecular weight fuel (e.g., the primary fuel 50 ) during start up. During partial load conditions, the HHC 52 may be slowly introduced in order to increase the molecular weight and heating value of the fuel mixture 34 . At steady-state, the HHC 52 may be maintained in order to control the heating value of the mixture 34 , as explained earlier. For example, the HHC 52 may be between approximately 0 to 30, 5 to 25, 10 to 20, or 12 to 18 percent of the total flow of the fuel mixture 34 , depending on the operating mode of the gas turbine system 10 . In addition, the percent of the HHC 52 may be the same or different between the fuel nozzles 32 (e.g., central fuel nozzle 48 and outer fuel nozzles 46 )
[0039] The configuration of the fuel nozzles 32 may also vary, as described below with respect to FIGS. 4-6 . For example, FIG. 4 illustrates an embodiment of the fuel nozzle 32 with a plurality of swirl vanes 74 to mix the air 28 with the fuel mixture 34 . As shown, the fuel nozzle 32 includes an inner wall 76 defining a central passage 78 . Additionally, a shroud 80 surrounds the inner wall 76 , thereby defining an annular passage 82 .
[0040] During operation of the fuel nozzle 32 , the air 28 flows through the annular passage 82 toward a combustion region 84 . As illustrated, the fuel mixture 34 (e.g., primary fuel 50 and HHC 52 ) flows through the central passage 78 and enters the annular passage 82 through orifices 86 of the swirl vanes 74 . For example, FIG. 5 is a perspective view of an embodiment of the swirl vane 74 having orifices 86 . As noted earlier, the operability of the fuel nozzle 32 may be affected by the pressure drop of the fuel mixture 34 across the fuel nozzle 32 . For example, the stability of the combustion flame may be affected by the pressure drop of the fuel mixture 34 across the orifices 86 . Turning back to FIG. 4 , sensors 88 and 90 are disposed within the fuel nozzle 32 to detect the pressure drop across the orifices 86 . In certain embodiments, the sensor 90 measure pressure detects fluctuations caused by the combustion of the fuel mixture 34 and the air 28 . The sensors 88 and 90 are communicatively coupled to the controller 64 of FIG. 3 , which may adjust the control valves 58 , 60 , and 62 in response to the pressure drop detected by the sensors 88 and 90 . For example, the pressure fluctuations may be used to determine respective flow rates of the HHC 52 and/or the diluent 56 .
[0041] A mixture 92 of the air 28 and the fuel 34 flows to the combustion region 84 , where the mixture 92 combusts, forming a combustion flame 94 . As shown, the combustion flame 94 occupies a volume 96 , which may be adjusted by adding the HHC 52 or the diluent 56 to the primary fuel 50 , as explained in detail above.
[0042] FIG. 6 illustrates another embodiment of the fuel nozzle 32 with a plurality of pilot tubes 98 to mix the air 28 with the fuel mixture 34 (e.g., primary fuel 50 and HHC 52 ). During operation of the fuel nozzle 32 , the air 28 flows through the central passage 78 and axially 14 into the plurality of pilot tubes 98 . The fuel mixture 34 flows through the annular passage 82 and radially 16 into the pilot tubes 98 . In certain embodiments, the fuel 34 may be supplied through one or more feed tubes. The air 28 and the fuel 34 mix within the pilot tubes 98 , and the mixture 92 of air 28 and fuel 34 is subsequently directed into the combustion region 84 . However, it should be noted that a variety of other configurations of fuel nozzles 32 with varying flow paths for the air 28 and the fuel 34 may be used. The sensors 88 and 90 are disposed within the annular passage 82 and the central passage 78 , respectively. The sensor 88 measures an upstream pressure of the fuel 34 (e.g., upstream of the pilot tubes 98 ), whereas the sensor 90 measures a downstream pressure of the fuel 34 (e.g., downstream of the pilot tubes). In certain embodiments, it may be desirable to adjust the composition of the fuel mixture 34 to improve the stability of the flame 94 based on the pressures detected by the sensors 88 and 90 . As explained earlier, the composition of the fuel 34 may be controlled by adjusting the control valves 58 , 60 , and 62 , which in turn are controlled by the controller 64 .
[0043] It should be noted that the embodiments of the fuel nozzles 32 and their respective geometries are not intended to be limiting. For example, the fuel mixture 34 may flow through the central passage 78 and air may flow through the annular passage 82 and vice versa. Indeed, the disclosed techniques may be applied to a variety of fuel nozzle designs, all of which fall within the scope and spirit of the present disclosure.
[0044] Technical effects of the disclosed embodiments include the use of the HHC 52 to adjust a fuel composition of the fuel mixture 34 . The composition of the fuel mixture 34 is varied in order to adjust certain properties (e.g., energy density or heating value) of the fuel 34 , which, in turn, adjusts the pressure, temperature, length, volume, or another parameter of the combustion flame 94 . The HHC 52 has a higher molecular weight, density, and/or energy density than the primary fuel 50 , which enables various properties of the fuel mixture 34 to be adjusted. In particular, the energy density of the fuel mixture 34 may be adjusted while maintaining an approximately constant heat input to the combustor 24 by varying the flow rate of the HHC 52 and/or the diluents 56 . Additionally or alternatively, the pressure drop across the fuel nozzle 32 may be adjusted while maintaining an approximately constant energy output. These adjustments improve the stability of the combustion flame 94 , and subsequently, improve the efficiency and operability of the gas turbine system 10 .
[0045] This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims. | A system includes a fuel supply system. The fuel supply includes a primary fuel supply, a fuel additive supply, and a common pipeline coupled to the primary fuel and fuel additive supplies. The primary fuel supply includes a primary fuel having a first average molecular weight. The fuel additive includes a fuel additive having a second molecular weight that is greater than the first average molecular weight. The common pipeline is configured to direct a mixture of the primary fuel and the fuel additive into a fuel nozzle. | 5 |
CLAIM OF PRIORITY
[0001] This application claims priority from U.S. provisional application No. 60/560,615, entitled “OPTICAL PROXIMITY CORRECTION USING CHAMFERS AND ROUNDING AT CORNERS,” filed Apr. 9, 2004, the disclosure of which is incorporated herein by reference in its entirety.
FIELD OF THE INVENTION
[0002] The present invention relates to photolithography, and in particular optical proximity techniques correction using chamfers and rounding at corners.
BACKGROUND
[0003] Lithographic apparatus can be used, for example, in the manufacture of integrated circuits (ICs). In such a case, the mask used in manufacture may contain a circuit pattern corresponding to an individual layer of the IC, and this pattern can be imaged onto a target exposure field (e.g. comprising one or more dies) on a substrate (silicon wafer) that has been coated with a layer of radiation-sensitive material (resist). In general, a single wafer will contain a whole network of adjacent target exposure fields that are successively irradiated via the projection system, one at a time. In one type of lithographic projection apparatus, each target exposure field is irradiated by exposing the entire mask pattern onto the target exposure field in one go; such an apparatus is commonly referred to as a wafer stepper. In an alternative apparatus—commonly referred to as a step-and-scan apparatus—each target exposure field is irradiated by progressively scanning the mask pattern under the projection beam in a given reference direction (the “scanning” direction) while synchronously scanning the substrate table parallel or anti-parallel to this direction. Since, in general, the projection system will have a magnification factor M (generally <1), the speed V at which the substrate table is scanned will be a factor M times that at which the mask table is scanned. More information with regard to lithographic devices as described herein can be gleaned, for example, from U.S. Pat. No. 6,046,792, incorporated herein by reference.
[0004] In a manufacturing process using a lithographic projection apparatus, a mask pattern is imaged onto a substrate that is at least partially covered by a layer of radiation-sensitive material (resist). Prior to this imaging step, the substrate may undergo various procedures, such as priming, resist coating and a soft bake. After exposure, the substrate may be subjected to other procedures, such as a post-exposure bake (PEB), development, a hard bake and measurement/inspection of the imaged features. This array of procedures is used as a basis to pattern an individual layer of a device, e.g. an IC. Such a patterned layer may then undergo various processes such as etching, ion-implantation (doping), metallization, oxidation, chemo-mechanical polishing, etc., all intended to finish off an individual layer. If several layers are required, then the whole procedure, or a variant thereof, will have to be repeated for each new layer. Eventually, an array of devices will be present on the substrate (wafer). These devices are then separated from one another by a technique such as dicing or sawing, whence the individual devices can be mounted on a carrier, connected to pins, etc.
[0005] For the sake of simplicity, the projection system may hereinafter be referred to as the “lens;” however, this term should be broadly interpreted as encompassing various types of projection systems, including refractive optics, reflective optics, and catadioptric systems, for example. The radiation system may also include components operating according to any of these design types for directing, shaping or controlling the projection beam of radiation, and such components may also be referred to below, collectively or singularly, as a “lens”. Further, the lithographic apparatus may be of a type having two or more substrate tables (and/or two or more mask tables). In such “multiple-stage” devices the additional tables may be used in parallel, or preparatory steps may be carried out on one or more tables while one or more other tables are being used for exposures. Twin stage lithographic apparatus are described, for example, in U.S. Pat. No. 5,969,441, incorporated herein by reference.
[0006] The photolithographic masks referred to above comprise geometric patterns corresponding to the circuit components to be integrated onto a silicon wafer. The patterns used to create such masks are generated utilizing CAD (computer-aided design) programs, this process often being referred to as EDA (electronic design automation). Most CAD programs follow a set of predetermined design rules in order to create functional masks. These rules are set by processing and design limitations. For example, design rules define the space tolerance between circuit devices (such as gates, capacitors, etc.) or interconnect lines, so as to ensure that the circuit devices or lines do not interact with one another in an undesirable way. The design rule limitations are typically referred to as “critical dimensions” (CD). A critical dimension of a circuit can be defined as the smallest width of a line or the smallest space between two lines. Thus, the CD determines the overall size and density of the designed circuit.
[0007] Of course, one of the goals in integrated circuit fabrication is to faithfully reproduce the original circuit design on the wafer (via the mask). However, because of the increasingly microscopic size of lithographic features and high resolution systems, the resulting features printed on the substrate tend to have some rippling, i.e., edges that are supposed to be straight are not straight. This rippling is related to “ringing” in filter theory, and is a natural side effect of efforts to accentuate the high spatial frequencies needed to image small features. Others factors that may cause rippling are known by those of ordinary skill in the art. FIG. 1 illustrates features printed on a substrate suffering from the problem of rippling.
[0008] In the current state of the art, model-based OPC corrects for mismatch between a target image and predicted image using the following steps. (1) A target layer is divided into a plurality of sections. (2) A predicted image is evaluated at one “evaluation point” (typically at the center) of each section of the plurality of sections. (3) Based on respective evaluations, features to be printed are modified in accordance with the respective evaluation at the center of the corresponding section to minimize the mismatch between the target and predicted image. In low k1 systems with the occurrence of rippling, or in systems where rippling is more prevalent, the conventional model based OPC methods accentuate rippling, as shown generally by FIG. 1 , in cases where the evaluation points happen by chance not to be placed in ideally representative locations within their respective sections.
[0009] More particularly, FIG. 2 illustrates a target image 20 superimposed on a predicted image 22 , which has rippling. The target image 20 is divided into a plurality of sections 24 , and the images 22 , 24 are evaluated at evaluation points 26 for each section 24 . Each evaluation point 26 is located at the center of the respective section 24 . Based on these evaluations, the target image is modified (modified mask 30 ), as illustrated by FIG. 3 . The modified mask takes into account the mismatch between the target image 20 and predicted image 22 . With respect to the evaluation at the center of each of the plurality of sections 24 , an offset of Δn is applied to the target image 20 , where n represents the corresponding section 24 . In other words, the resulting new edge is adjusted downwardly in each place where the original predication was high, and is adjusted upwardly in each place where the original prediction was low, as would be expected.
[0010] FIG. 4 illustrates the new predicted image 40 based on the modified mask 30 . By comparison with the predicted image 22 , in the given example conventional model based OPC accentuates rippling of the new predicted image 40 , which increases the likelihood of breaking or bridging depending on surrounding structure.
[0011] Improved results can in principle be obtained by choosing a “better” evaluation point, and some limited strategies exist in this regard. In particular, the evaluation points of sections at or near corners may be moved back away from that corner to avoid over-correction. These methods are helpful, but are difficult to apply except in simple cases due to the complexity of the interaction between surrounding contextual features and the ripples observed on a particular edge of interest.
[0012] Moreover, model based OPC uses either an aerial model or a calibrated model. A calibrated model must consider mask properties, characteristics of the tools to create the mask, resist properties, etc. Because of this, there are many disadvantages to using a calibrated model. They include extensive calibration, including building a mask and exposing wafers, and factoring in arbitrary imaging properties that cannot be attributed to the mask, semiconductor, or any associated property. The main disadvantage is that in order to calibrate a model, a reasonable mask must already exist. Thus, industry often uses the aerial model for model based OPC, because it is expedient and does not rely on existing tools. However, aerial models do not factor in product and manufacturing imperfections, as in the case of using a calibrated model.
[0013] There has yet to be created a way for eliminating mismatch between a target image and predicted image to approximate real life imperfections.
SUMMARY
[0014] The teachings herein alleviate the above noted problems and provide a novel method of optimizing a design to be formed on a substrate. The steps include approximating rounding of at least one corner of an image of the design; generating a representation of the design further to the approximate rounding of the at least one corner; generating an initial representation of a mask utilized to image the design based on the representation; and performing Optical Proximity Correction (OPC) further to the initial representation of the mask.
[0015] OPC includes the steps of generating an image of the design further to the initial representation of the mask; evaluating deviation between the representation of the design further to the approximate rounding and the image; and determining whether a result of the evaluation of Step satisfies predefined constraints. In the event the result does not satisfy predefined constraints, a next representation of the mask may be generated in accordance with the results and OPC is repeated until the deviation meets predefined constraints.
[0016] Determination of approximate rounding may be based on a derivation of predefined rule, which may be used to define dimensions of a serif. Furthermore, rounding may be approximated by selecting a size of a cutout from a chamfer and chamfering the at least one corner to approximate rounding in accordance with the size of the cutout.
[0017] When the chamfered corner is adjacent to another corner, further adjustments may be necessary, such as reducing the size of at least one of the first chamfer and the second chamfer so that the first chamfer and the second chamfer do not intersect. Alternatively, the size of the first chamfer and the second chamfer may be reduced proportionally so that the first chamfer and the second chamfer do not intersect.
[0018] Yet another novel concept includes a method for enhancing OPC. The steps include determining rounding of corners of the initial representation of the mask based on mask manufacturing constraints; and generating a modified mask representation based on the initial representation in which corner rounding is applied. Rounding at each corner has a predetermined radius.
[0019] Accordingly, both rounding of corners due to imaging constraints and rounding of mask corners due to mask manufacturing constraints may be factored.
[0020] Additional objects, advantages and novel features will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following and the accompanying drawings or may be learned by production or operation of the examples. The objects and advantages of the present teachings may be realized and attained by practice or use of the methodologies, instrumentalities and combinations particularly pointed out in the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] The drawing figures depict one or more implementations in accordance with the present teachings, by way of example only, not by way of limitation. In the figures, like reference numerals refer to the same or similar elements.
[0022] FIG. 1 illustrates exemplary features printed on a substrate suffering from rippling.
[0023] FIG. 2 illustrates an exemplary target image and corresponding predicted image suffering from rippling.
[0024] FIG. 3 illustrates the target and predicted images of FIG. 2 and an exemplary modified mask based on the evaluation of the images of FIG. 2 .
[0025] FIG. 4 illustrates an exemplary predicted image based on the modified mask of FIG. 3 .
[0026] FIG. 5A illustrates an ideal feature to be printed, and
[0027] FIG. 5B illustrates the corresponding actual feature to be printed.
[0028] FIG. 6A illustrates the overlap portion of a negative serif relative to a feature, and
[0029] FIG. 6B illustrates the overlap portion of a positive serif relative to the feature.
[0030] FIG. 7A illustrates possible interference of chamfering at adjacent corners, and
[0031] FIG. 7B illustrates chamfering adjustments to resolve the interference.
[0032] FIG. 8 illustrates a simulation of a target image, serifs applied to the target image, and chamfering of the target image.
[0033] FIG. 9 illustrates simulation preformed using a median evaluation of a modified target image adjusted for chamfering at each corner.
[0034] FIG. 10 illustrates the same simulation as in FIG. 9 but for an unmodified target image.
[0035] FIG. 11 illustrates a exemplary flow chart of the model OPC loop.
[0036] FIG. 12 illustrates a target image, modified by chamfering to simulate rounding, and a target image modified in step to apply rounding.
[0037] FIG. 13 illustrates a flowchart generally applying rounding during the corresponding step of FIG. 11 .
[0038] FIG. 14 illustrates a corner, which has been rounded, at the wafer level.
[0039] FIG. 15 schematically depicts a lithographic projection apparatus suitable for use with a mask designed with the aid of the current invention.
DESCRIPTION
[0040] Described in related U.S. patent application No. 60/557,833 (the “'833” patent application), entitled “Apparatus, Method and Program Product for Suppressing Waviness of Features to be printed using Photolithographic Systems,” filed on Mar. 30, 2004, are novel concepts for overcoming inconsistencies in a predicted image, by adjusting a mask accordingly. This application is incorporated herein by reference in its entirety.
[0041] The inventors have further devised novel concepts for reducing rippling of a predicted image and other negative affects by compensating the target image for known printing manufacture limitations. With regard to one such limitation, there has yet been devised a way to print corners beyond a predetermined sharpness. For instance, FIG. 5A illustrates an ideal feature 50 , and FIG. 5B illustrates the actual feature 52 printed or a predicted image of the feature 52 . The ideal feature 50 has an ideal corner 54 of an infinite sharpness, but because of manufacturing and physical limitations, the shape of ideal corner 54 is practically unachievable.
[0042] Described in the '833 application are novel approaches for compensating for corner rounding in the target image in model OPC. These included applying adjustment factors to evaluations taken nearing a corner or at a corner. Alternatively, evaluation points nearing and located at a corner may be eliminated entirely. Because corners will always have some rounding, the adjustment factor takes this into account, and adjustments are made to the target image accordingly.
[0043] As in the present invention, another novel approach is to modify the target image to simulate rounding at each corner. Corners will always suffer some rounding during the printing process, and OPC treatments can introduce undesirable results (“ringing”, “necking”, and “bridging”) as a result of attempting to correct for this inevitable rounding. Whereas the '833 application teaches methods by which mismatches due to corner rounding can be selectively ignored, the present invention alters the target in a way that approximates the inevitable corner rounding, and then applies OPC to attempt to reproduce this modified target.
[0044] There has been much development of rule-based OPC using serifs. U.S. Pat. Nos. 5,663,893, 5,707,765 and 6,670,081 provide exemplary descriptions of OPC using serifs. These patents are incorporated herein by reference in their entirety.
[0045] Generally serifs are sub-lithographic square shaped features positioned on corners of a circuit feature. They serve to “sharpen” the corners in the final transferred design on a wafer, for improving the correspondence between the actual circuit design and the final transferred circuit pattern on the photoresist layer. It is known that “positive” serifs at convex vertices adjust exposure energy of the mask at the vertex to prevent loss of the corner. “Negative” serifs at concave vertices remove a portion of the mask pattern at the concave vertex so as to attempt to maintain an accurate representation of the concave vertex in the final pattern. Based on the rules developed for optimizing serifs, there is a general understanding of the limitations of the “sharpness of a corner.”
[0046] In typical OPC using serifs, each edge of a given serif (both positive and negative) is adjustable relative to every other edge of a given serif so as to allow the overall dimension of the serif to be modified. As well, each serif can be modified independently of every other serif. As the '081 patent explains, these modifications of serifs are governed by predefined rules, which are selected/defined by the user in accordance with the feature pattern to be generated. It is well known that such rules will vary in accordance with different circuit design features. Of course, these rules may also be of the sort for serifs of fixed dimensions and spacing threshold(s).
[0047] FIGS. 6A and 6B illustrates a pattern to be printed using serifs. The positions and dimensions of the serifs have been exaggerated for purposes of illustration and explanation. Each serif has an “overlap portion” and an “extension portion.” The portion of a negative serif that overlaps the background of the feature is the overlap portion ( FIG. 6A ), whereas the portion of a positive serif that overlaps the actual feature is the overlap portion ( FIG. 6B ). The overlap of the serif can be defined as “short overlap” O S and “long overlap” O L . Similarly, extensions can be defined as a “short extension” E S and a “long extension” E L . Using any rule-based approach for sizing and positioning serifs, each serif for a given corner can be defined.
[0048] The inventors have found that the optimal chamfer, i.e. corner cutoff, can be derived in the same way as optimal serif dimensions. The optimal chamfering rules may differ from the ideal rules for serif correction, but the rules will be similar in form. Referring back to FIG. 5B , it is assumed that the rounding of corner 56 has been minimized using serifs, as described above, and what remains is the residual corner rounding that cannot be eliminated. By chamfering corner 54 ′ to approximate or simulate this expected rounding before OPC, as seen in FIG. 5B , the subsequent OPC treatment will not be led to compromise the correction of nearby areas in an attempt to eliminate corner rounding.
[0049] As shown in FIG. 5B corner rounding takes the form of a smooth curve. Such a shape is difficult or impossible for conventional EDA software to handle. The corner may be approximated with a sequence of straight edges, in a “polygonal” approximation. A compromise may be found between the simplicity of such a polygon and the precision with which it approximates the ideal curved figure. The inventors have found a single diagonal edge, with symmetrical 45-degree angles at each end, to be a good compromise in most cases. Restricting the geometry to edges at angles that are multiples of 45 degrees has practical advantages in mask making, because most mask-writing machines must approximate other angles using a “stairstep” pattern. However, it shall be understood that a larger number of diagonal edges, and in some cases an angle other than 45 degrees, can better approximate the true corner rounding, and may be preferred in particular situations.
[0050] Assuming the case of a single chamfering edge, without restricting its angle, the chamfer cutout would be a triangle, chosen so that one of its legs equals the short overlap O S , and the other equals the long overlap O L . The values of E S and E L , which are necessary to define a serif, are ignored when creating this chamfer. O S and O L normally differ in length because of differences in the lengths of the two original target edges, with the overlap shorter along the shorter edge. This approximates the asymmetrical curve of the actual corner rounding found in such cases. To restrict the angle to 45 degrees, as in the preferred embodiment of this invention, the two legs of the triangle must have the same length, and the shorter length, O S , is chosen.
[0051] Corners that are connected by two relatively long lines, such that the corner rounding (and the chamfering that approximates it) of one corner does not interfere with that of an adjacent corner, will have both O S and O L equal to some nominal chamfer amount. However, when lines between adjacent corners are relatively short, such as at an end of a line, sometimes referred to as a “U” edge, chamfering of one corner may interfere with the chamfering of an adjacent corner. This concept is illustrated by FIG. 7A .
[0052] Typically, rules for serifs distinguish between placing a serif on a convex corner and a concave corner. Taking the convex rules as an example, consider a “nominal” serif size rule (corresponding to a chamfer size rule) of 40 nm. However, on short “U edges”, as seen in FIG. 7B , the chamfer may be reduced so as to cut only one quarter of the line end. Of course, these rules may be modified so that the chamfer may cut any fraction of the line below one-half of the line end, for maintaining a “true” U edge.
[0053] This may be accomplished with the “ps_adj” (positive serif adjustment rule) parameter with an adjustment to the “parallel overlap” of the chamfer that is linearly dependent on the length of the U edge. For example, the nominal chamfer width could be 40 nm, and the parallel overlap adjustment could vary linearly from 0 nm at an edge length of 160 nm to −20 nm at an edge length of 80 nm. This produces a chamfer that is ¼ of the line width W, for any line width between 80 nm and 160 nm. At one end of this range, a 160 nm-wide line receives no adjustment, and the 40 nm nominal chamfer size is exactly ¼ of the 160 nm line width. At the other end of this range, an 80 nm-wide line receives a −20 nm adjustment to the 40 nm nominal chamfer size, yielding a 20 nm chamfer, which is again ¼ of the line width.
[0054] FIG. 8 illustrates a target image 800 (dashed line), serifs 802 (diagonal hatching), and the related chamfered 804 resulting at each corner of the feature to be printed. Serif 802 and chamfer 804 dimensions have been exaggerated for illustration and explanation purposes only, and may not be best for the given pattern. In addition, serifs 802 and chamfers 804 are illustrated in the same image to simply demonstrate the concepts discussed above for determining chamfer 804 dimensions.
[0055] FIG. 9 illustrates simulated results from corrections performed using median evaluation, described in patent application number '833, and in accordance with the novel concepts discussed herein. FIG. 10 illustrates simulated results from corrections performed using median evaluation, described in patent application number '833 only. In FIG. 9 , the target image is designated by 900 (dashed line), the corrected mask pattern by 902 (diagonal hatching), and the predicted printing results by 904 (horizontal hatching). In FIG. 10 , the target image is designated by 1000 (dashed line), the corrected mask pattern by 1002 (diagonal hatching) and the predicted printing results by 1004 (horizontal hatching).
[0056] Areas A-E designated in each figure have been chosen for comparing the effects of bridging, necking (or pinching), rippling, line smoothing, and average line width. Bridging has been reduced, as best seen by referring to A and B in FIG. 9 as compared to the same in FIG. 10 . Rippling has been reduced, as best seen by referring to C in FIG. 9 as compared to the same in FIG. 10 . Average line width and line smoothing is better, as best seen by referring to C and D in FIG. 9 as compared to the same in FIG. 10 . Necking has been reduced, as best seen by referring to E in FIG. 9 as compared to the same in FIG. 10 .
[0057] Even though the aforementioned modified target image for approximating rounding is a good approximation, the target image is still nonetheless an ideal representation. Please consider the further enhancements described below.
[0058] The model OPC loop for creating the above images is as follows: (1) define mask representation corresponding to the target, (2) calculate image (aerial image or in resist), (3) determine deviation between image and target, (4) modify mask, (5) repeat until image is satisfactory. By modifying the target image for chamfered corners, this model OPC loop, as discussed above, indeed generates a superior image. However, the model OPC can be modified further to take into consideration actual corner rounding, on the target, mask or both.
[0059] A mask construction function and/or target image modification function may be incorporated in the model OPC loop to factor in mask rounding that will inevitably occur with practically all lithographic printing of features having corners. FIG. 11 illustrates a exemplary flow chart of the model OPC loop incorporating both of these concepts. In Step 1100 , an initial target image is defined, such as the target image 800 illustrated by FIG. 8 . In Step 1101 , the initial estimation of the mask is chosen to be equal to the target, defined prior to Step 1101 . Steps A and B may be incorporated following Step 1100 , in which an ideal target is chosen, i.e., a target having sharp corners, and approximate rounding or chamfers is applied to respective corners of the target image, respectively. This way a more realistically achievable target is generated. This step of approximating rounding of the target accounts for the a priori knowledge that the projection system acts as a low pass filter, and hence will never be able to image sharp corners.
[0060] In Step 1102 , rounding may be applied to the initial estimation of the mask to factor in the actual rounding of corners of features on an actual mask (Step 1102 ). The rounding is typically due to mask manufacturing constraints. Such manufacturing constraints are well known to those of ordinary skill in the art. In Step 1104 , an image is generated based on the mask representation generated in Step 1102 , and in Step 1106 , deviation between the image generated and the representation is determined. Based on predefined constraints, it is determined whether the image is satisfactory (Step 1108 ). The manner of setting predefined constraints and judging whether an image is satisfactory is well known within the lithography art. If the image is acceptable, the process is ended (Step 1110 ) and a mask may be generated based on the representation of the mask used to generate the image of Step 1104 . Alternatively, if the image is unsatisfactory, the representation of the mask may be modified in accordance with well-known OPC techniques (Step 1112 ). Steps 1102 - 1108 are repeated until the image is satisfactory.
[0061] FIG. 12 demonstrates the similarity between the target modification of Step B ( FIG. 11 ) and modification of the mask representation (Step 1102 ). More particularly, FIG. 12 illustrates a target image 1200 , modified by chamfering to simulate rounding, and a mask representation 1202 modified in step 1104 to apply rounding. Target 1200 has been enlarged slightly relative to target image 1202 for illustration and explanation purposes. By applying rounding to the mask representation, a better representation of imperfections of corners, can be approximated. Furthermore, the actual rounding of the mask representation complements the target image to which approximate rounding has been applied. In other words, the actual rounding of the mask representation can be said to round the chamfered corners of the target image.
[0062] FIG. 12 also illustrates yet another concept in which each corner is rounded at the predetermined radius, r. As discussed herein, effects of rounding is known, and can be approximated generally for most types of printing. For instance, the inventors have found that for a typical mask making process radii in the range of 40-80 nm, measured at the reticule, can be expected. Of course, radii of different magnitudes can be chosen depending on complexity of the mask feature and mask making process or mask-writer system parameters.
[0063] FIG. 13 illustrates a flowchart generally applying rounding during Step 1102 of FIG. 11 . Generally, each corner is examined, as in Step 1300 , and rounding of a predetermined radius is applied, in step 1302 . In step 1304 , a modified mask representation (See 1202 , FIG. 12 ) is generated, and OPC is conducted based on this image. FIG. 14 further illustrates this concept. A corner 1400 , which has been rounded 1404 , at the wafer level basically corresponds to the size of the chamfer 1402 of the target image.
[0064] Accordingly, either or both the modification of the target image to approximate rounding or modification of the representation of the mask to simulate rounding due to mask manufacturing constraints may be used to optimize the final mask.
[0065] FIG. 15 schematically depicts a lithographic projection apparatus suitable for use with a mask designed with the aid of the current invention. The apparatus comprises:
[0066] a radiation system Ex, IL, for supplying a projection beam PB of radiation. In this particular case, the radiation system also comprises a radiation source LA;
[0067] a first object table (mask table) MT provided with a mask holder for holding a mask MA (e.g. a reticle), and connected to first positioning means for accurately positioning the mask with respect to item PL;
[0068] a second object table (substrate table) WT provided with a substrate holder for holding a substrate W (e.g. a resist-coated silicon wafer), and connected to second positioning means for accurately positioning the substrate with respect to item PL;
[0069] a projection system (“lens”) PL (e.g. a refractive, catoptric or catadioptric optical system) for imaging an irradiated portion of the mask MA onto a target portion C (e.g. comprising one or more dies) of the substrate W.
[0070] As depicted herein, the apparatus is of a transmissive type (i.e., has a transmissive mask). However, in general, it may also be of a reflective type, for example with a reflective mask. Alternatively, the apparatus may employ another kind of patterning means as an alternative to the use of a mask; examples include a programmable mirror array or LCD matrix.
[0071] The source LA (e.g. a mercury lamp or excimer laser) produces a beam of radiation. This beam is fed into an illumination system (illuminator) IL, either directly or after having traversed conditioning means, such as a beam expander Ex, for example. The illuminator IL may comprise adjusting means AM for setting the outer and/or inner radial extent (commonly referred to as σ-outer and σ-inner, respectively) of the intensity distribution in the beam. In addition, it will generally comprise various other components, such as an integrator IN and a condenser CO. In this way, the beam PB impinging on the mask MA has a desired uniformity and intensity distribution in its cross-section.
[0072] It should be noted with regard to FIG. 15 that the source LA may be within the housing of the lithographic projection apparatus (as is often the case when the source LA is a mercury lamp, for example), but that it may also be remote from the lithographic projection apparatus, the radiation beam that it produces being led into the apparatus (e.g. with the aid of suitable directing mirrors); this latter scenario is often the case when the source LA is an excimer laser (e.g. based on KrF, ArF or F 2 lasing). The current invention encompasses at least both of these scenarios.
[0073] The beam PB subsequently intercepts the mask MA, which is held on a mask table MT. Having traversed the mask MA, the beam PB passes through the lens PL, which focuses the beam PB onto a target portion C of the substrate W. With the aid of the second positioning means (and interferometric measuring means IF), the substrate table WT can be moved accurately, e.g. so as to position different target portions C in the path of the beam PB. Similarly, the first positioning means can be used to accurately position the mask MA with respect to the path of the beam PB, e.g., after mechanical retrieval of the mask MA from a mask library, or during a scan. In general, movement of the object tables MT, WT will be realized with the aid of a long-stroke module (coarse positioning) and a short-stroke module (fine positioning), which are not explicitly depicted in FIG. 15 . However, in the case of a wafer stepper (as opposed to a step-and-scan tool) the mask table MT may just be connected to a short-stroke actuator, or may be fixed.
[0074] The depicted tool can be used in two different modes:
[0075] In step mode, the mask table MT is kept essentially stationary, and an entire mask image is projected in one go (i.e., a single “flash”) onto a target portion C. The substrate table WT is then shifted in the x and/or y directions so that a different target portion C can be irradiated by the beam PB;
[0076] In scan mode, essentially the same scenario applies, except that a given target portion C is not exposed in a single “flash.” Instead, the mask table MT is movable in a given direction (the so-called “scan direction”, e.g., the y direction) with a speed v, so that the projection beam PB is caused to scan over a mask image; concurrently, the substrate table WT is simultaneously moved in the same or opposite direction at a speed V=Mv, in which M is the magnification of the lens PL (typically, M=¼ or ⅕). In this manner, a relatively large target portion C can be exposed, without having to compromise on resolution.
[0077] The concepts disclosed herein may simulate or mathematically model any generic imaging system for imaging sub wavelength features, and may be especially useful with emerging imaging technologies capable of producing wavelengths of an increasingly smaller size. Emerging technologies already in use include EUV (extreme ultraviolet) lithography that is capable of producing a 193 nm wavelength with the use of a ArF laser, and even a 157 nm wavelength with the use of a Fluorine laser. Moreover, EUV lithography is capable of producing wavelengths within a range of 20-5 nm by using a synchrotron or by hitting a material (either solid or a plasma) with high-energy electrons in order to produce photons within this range. Because most materials are absorptive within this range, illumination may be produced by reflective mirrors with a multi-stack of Molybdenum and Silicon. The multi-stack mirror has a 40 layer pairs of Molybdenum and Silicon where the thickness of each layer is a quarter wavelength. Even smaller wavelengths may be produced with X-ray lithography. Typically, a synchrotron is used to produce an X-ray wavelength. Since most material is absorptive at x-ray wavelengths, a thin piece of absorbing material defines where features would print (positive resist) or not print (negative resist).
[0078] While the concepts disclosed herein may be used for imaging on a substrate such as a silicon wafer, it shall be understood that the disclosed concepts may be used with any type of lithographic imaging systems, e.g., those used for imaging on substrates other than silicon wafers.
[0079] The concepts disclosed herein may be used as a simulator, i.e., as a computer program product capable of being implemented on a computer system. Software functionalities of the computer system involve programming, including executable code, which may be used to implement the above-described imaging model. The software code is executable by the general-purpose computer. In operation, the code and possibly the associated data records are stored within a general-purpose computer platform. At other times, however, the software may be stored at other locations and/or transported for loading into the appropriate general-purpose computer systems. Hence, the embodiments discussed above involve one or more software products in the form of one or more modules of code carried by at least one machine-readable medium. Execution of such code by a processor of the computer system enables the platform to implement the catalog and/or software downloading functions, in essentially the manner performed in the embodiments discussed and illustrated herein.
[0080] As used herein, terms such as computer or machine “readable medium” refer to any medium that participates in providing instructions to a processor for execution. Such a medium may take many forms, including but not limited to, non-volatile media, volatile media, and transmission media. Non-volatile media include, for example, optical or magnetic disks, such as any of the storage devices in any computer(s) operating as one of the server platform, discussed above. Volatile media include dynamic memory, such as main memory of such a computer platform. Physical transmission media include coaxial cables; copper wire and fiber optics, including the wires that comprise a bus within a computer system. Carrier-wave transmission media can take the form of electric or electromagnetic signals, or acoustic or light waves such as those generated during radio frequency (RF) and infrared (IR) data communications. Common forms of computer-readable media therefore include, for example: a floppy disk, a flexible disk, hard disk, magnetic tape, any other magnetic medium, a CD-ROM, DVD, any other optical medium, less commonly-used media such as punch cards, paper tape, any other physical medium with patterns of holes, a RAM, a PROM and EPROM, a FLASH-EPROM, any other memory chip or cartridge, a carrier wave transporting data or instructions, cables or links transporting such a carrier wave, or any other medium from which a computer can read programming code and/or data. Many of these forms of computer readable media may be involved in carrying one or more sequences of one or more instructions to a processor for execution.
[0081] While the foregoing has described what are considered to be the best mode and/or other examples, it is understood that various modifications may be made therein and that the subject matter disclosed herein may be implemented in various forms and examples, and that the teachings may be applied in numerous applications, only some of which have been described herein. It is intended by the following claims to claim any and all applications, modifications and variations that fall within the true scope of the present teachings. | Disclosed is a method of optimizing a design to be formed on a substrate. The method includes approximating rounding of at least one corner of an image of the design; generating a representation of the design further to the approximate rounding of the at least one corner; generating an initial representation of a mask utilized to image the design based on the representation; and performing Optical Proximity Correction (OPC) further to the initial representation of the mask. | 6 |
BACKGROUND OF THE INVENTION
The invention relates to an axial piston machine having a device for the electrically proportional adjustment of its volumetric displacement according to the features of claim 1 .
Axial piston machines such as hydraulic pumps and motors in an open or closed circuit and of swash plate design or oblique axis design are often actuated using an electrically proportional adjustment. The input signal into this adjustment unit is an electrical current. Its output signal is a hydraulic pressure. The outgoing oil pressure acts on servopistons of the axial piston machine which thus move along their movement axis. This movement is transmitted, for example, to a swash plate which, by changing its angular position, changes the volumetric displacement of the axial piston machine.
The current position of the swash plate or oblique axis is fed back to the electrically actuated adjustment unit via a mechanical feedback system. By means of this feeding back of the position, the control circuit is closed and it is ensured that the volumetric displacement of the axial piston machine also behaves proportional to the electric current at the adjustment unit. The system has a control piston which moves by means of at least one proportional magnet, but generally is displaced along its movement axis by two proportional magnets which are arranged opposite one another at its end faces, and as a result connects or disconnects ducts in such a way that oil is made available with a specific pressure for moving the servopistons. In known axial piston machines, a lever and spring system is provided for this purpose, which system ensures that the angle of the swash plate or of the valve segment in relation to the oblique axis is fed back to the control piston.
Known feedback mechanisms have structurally induced problems. On the one hand, any form of mechanical hysteresis between levers, springs and proportional magnets adversely affects the desired proportional adjustment characteristic owing to the sensitive equilibrium of forces, and on the other hand previous solutions require differently dimensioned adjustment devices depending on the overall size of the axial piston machine, which adjustment devices give rise to large overall widths in some cases owing to the lever mechanisms which are used. The proportional magnets are then a correspondingly large distance apart from one another. Since they are mounted on an exposed position on the axial piston machine, this increases the risk of damage and makes it unsuitable to use such adjustment units on axial piston machines with a small volumetric displacement and correspondingly small installation space.
The invention is based on the object of providing an axial piston machine with improved adjustment system.
SUMMARY OF THE INVENTION
This object is achieved with the axial piston machine according to claim 1 . According to the invention, the axial piston machine has a swash plate which can be adjusted by means of servopistons, or in the case of an oblique axis machine a corresponding valve segment and an adjustment unit for electrically proportionally adjusting the volumetric displacement, the adjustment unit comprising proportional magnets which can be activated electrically, and a control piston for controlling the oil pressure which moves the servopistons, and the proportional magnets acting on this control piston along a common tappet axis. A feedback device for feeding back the current swash plate or oblique axis valve segment position is provided. The feedback device comprises spring levers and a pointer which is embodied as a two-armed lever, which can be pivoted about an axis, the pointer engaging in the control piston on one side of the pivot axis, and between the spring levers on the other side.
The spring levers on the pivot axis are preferably each mounted with a bearing shell, each of which is composed of two component shells which support the spring lever at separate locations on the axis and enclose the bearing of the pointer between them. With the exception of an angular range which remains free for the spreading of the spring levers, the bearing shell of each spring lever encloses a half-space about the pivot axis. This arrangement avoids a situation in which tilting moments which would lead to inaccuracies of the adjustment device and to increased frictional forces occur at the spring levers which are stressed one against the other.
A further advantageous refinement consists in the fact that the pointer is not mounted directly on the pivot axis but rather on the spring levers. The pointer always inevitably follows one of the spring levers. Frictional forces are significantly reduced by its mounting on the spring levers.
Embodiments in which the levers are each mounted in a fork-like fashion on the pivot axis are particularly advantageous, i.e. free of tilting moments, so that they are supported at two locations on the axis and thus enclose the bearing of the pointer 3 between them, or in which the pointer is mounted with a fork on the pivot axis, with the result that it is supported at two locations on the axis, the fork of the pointer enclosing the bearings of the spring levers.
For reasons of reducing friction, the pointer head and the faces of the spring levers on which it bears are processed separately, in particular coated in a friction-reducing fashion. The pointer head may be of cylindrical or spherical construction here, or have a rectangular cross section.
It is particularly advantageous if the end of the pointer which engages in the control piston is guided as a ball in a corresponding bore in the control piston, and the point of engagement of the pointer in the control piston lies outside the centre line of the piston. In this way, a largely hysteresis-free feedback is produced, which at the same time prevents the control piston from turning. In order to avoid one-sided loading of the control piston, and an associated tilting moment, the point of engagement of the pointer in the control piston lies on the tappet axis of the magnets, which axis is thus also offset towards the centre line of the control piston.
The control piston is preferably provided along its length with a bore through which oil, which escapes due to unavoidable leakages, is conducted away.
A great advantage of the present invention is that an entire series of axial piston machines with different volumetric displacements can be covered with the adjustment device, it being possible to use the same adjustment device for all models of the series by using the pointer.
Further refinements and advantages of the invention emerge from the subsequent description of the figures.
DESCRIPTION OF THE DRAWINGS
FIG. 1 shows the adjustment device of the axial piston machine in cross section,
FIG. 2 shows the adjustment device of the axial piston machine in a section which is perpendicular to FIG. 1 ,
FIGS. 3 a , 3 b , 3 c , 3 d show the bearing of the pointer and of the spring levers according to one embodiment of the invention,
FIGS. 4 a , 4 b , 4 c , 4 d show the bearing of the pointer and of the spring levers according to a third embodiment,
FIGS. 5 a , 5 b , 5 c , 5 d show the bearing of the pointer and of the spring levers on the pivot axis according to a fourth embodiment, and
FIGS. 6 a , 6 b , 6 c , 6 d show the bearing of the pointer and of the spring levers on the pivot axis according to a fifth embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 shows a cross section through the adjustment device 1 . A control piston 2 is adjusted along a movement axis perpendicularly to the cross section shown by means of proportional magnets, with the result that an oil pressure which acts on the servopistons (not shown here) is made available. A pointer 3 which is embodied as a two-armed lever engages in the control piston 2 , which, with its movement, rotates the pointer 3 about the pivot axis 5 . The pointer 3 is guided here in a bore of the control piston 2 outside its movement axis and centre line, by means of a ball guide 4 .
On each side of the pointer 3 , a spring lever 6 , 6 ′ is also mounted on the pivot axis 5 , this bearing being embodied in such a way that tilting moments are avoided as far as possible. Such tilting moments can be produced by the forces which are exerted on the spring levers 6 , 6 ′ by the control piston 2 and by the traction spring 7 which stresses the spring levers one against the other. It is possible, for example, to use roller bearings to mount the spring levers 6 , 6 ′ and the pointer 3 .
The pivot axis 5 is formed by a pin-shaped, cylindrical axial bolt 8 which is mounted on each side in the housing and has an eccentric section 9 in its central part on which the spring levers 6 , 6 ′ and the pointer 3 are mounted. The eccentricity is dimensioned here such that, by rotating the axial bolt 8 , the pivot axis 5 can be displaced sufficiently to be able to set the zero position. Owing to the small degree of offset, no particular distinction is made between the pivot axis 5 and the axis of rotation of the axial bolt 8 in the drawing.
The traction spring 7 is clamped into the fork-like ends 10 —facing away from the pivot axis 5 —of the spring levers 6 , 6 ′. On the one hand, the pointer head 14 rests on the bearing faces 11 , 11 ′ of the spring levers 6 , 6 ′, and if the bearing faces 11 , 11 ′ protrude beyond said pointer head 14 , a pin (not shown) which is connected to the swash plate and which transmits the angular position of the swash plate to the spring levers 6 , 6 ′ also bears on them. The pivoting movement of said swash plate is directed essentially perpendicularly to the plane of the drawing in FIG. 1 here.
The control piston 2 has a defined home position. It is brought about by the two spring levers 6 , 6 ′, the pointer 3 which is embodied as a two-armed lever, the traction spring 7 , the pivot axis 5 and a connection to the swash plate, in the following way: the spring levers 6 , 6 ′ and the pointer 3 are mounted together on the pivot axis 5 in a rotatable fashion. The spring levers 6 , 6 ′ are connected at their ends to a traction spring 7 which pulls the spring levers 6 , 6 ′ one against the other in the manner of a closing clamp, the spring levers 6 , 6 ′ enclosing one end of the pointer 3 and at the same time the mechanical contact with the swash plate which is pressed into its home position by strong spring forces. When the clamp which closes the contact with the swash plate is closed, the pointer 3 is also clamped in by its end lying between them, by the spring levers 6 , 6 ′, in such a way that its play between them is virtually zero. At its other end, the pointer 3 engages in the control piston 2 and holds it in its home position. In this home position, the control piston 2 does not conduct any oil to the servopiston and the swash plate is held in the neutral position by strong springs.
So that no oil is actually made available to the servopistons in the neutral position of the control pistons 2 , the position of the pointer 3 , which, as a result of the spring levers 6 , 6 ′, is already aligned at one end in relation to the swash plate, has to be appropriately set. This is done by displacing the pivot axis 5 .
If a sufficiently large electric current flows through one of the proportional magnets 12 , 12 ′, the control piston is pushed along its movement axis by the tappet of the proportional magnet. This forces the pointer 3 to rotate about the pivot axis 5 , and to spread apart the clamp formed from the spring levers 6 , 6 ′ and the traction spring 7 . In the process, the one spring lever 6 maintains mechanical contact with the swash plate, while the other spring lever 6 ′ rotates in the same direction with the pointer 3 about the pivot axis 5 , and thus moves out of mechanical contact with the swash plate.
As a result, owing to the movement of the control pistons, oil is fed to the servopistons of the axial piston machine and the swash plate is pivoted. The oilconducting connections are expediently embodied in such a way that the movement of the swash plate by means of the mechanical contact with respect to the spring lever 6 , which is still in the resting position, causes the latter to rotate in the opposite direction to the other spring lever 6 ′. As a result, the stretched traction spring 7 pulls the spring lever 6 ′—previously deflected by the proportional magnet and the pointer 3 —back into its home position, together with the pointer 3 and control piston 2 . In the process, the spring force and the force of the proportional magnet are balanced and a specific position of the swash plate is assigned to each force level.
FIG. 2 shows the adjustment device in a section which is perpendicular to FIG. 1 . In what follows, the same reference symbols as in FIG. 1 are retained for identical components. In the adjustment device 1 , the control piston 2 is moved by proportional magnets 12 , 12 ′, an oil flow which supplies the control piston being made available via the ducts 13 , 13 ′. The pointer 3 engages in a bore in the control piston 2 on one side of its pivot axis 5 , the point of engagement of its end 4 , which is of conical construction, lying on the tappet axis of the magnets 12 , 12 ′ and being offset with respect to the centre line of the control piston, in order to avoid tilting moments and rotation of the piston. There is a continuous bore through the centre of the control piston 2 along its centre line in order to conduct away leakage oil.
The pointer 3 engages between the spring levers 6 , 6 ′, on the side of the pivot axis facing away from the control piston 2 , and said pointer 3 lies with its head 14 on part of the bearing faces 11 , 11 ′, which parts are specially processed, in particular coated, in order to avoid abrasion. The same applies to the pointer head 14 which is circular-cylindrical in the example shown but may also be embodied with a rectangular cross section or in the shape of a sphere. A pin (not illustrated) which is connected to the swash plate and transmits its angular position rests on the part of the bearing faces 11 , 11 ′ which projects beyond the pointer head. When the control piston 2 moves, the pointer head 14 presses the spring levers 6 , 6 ′ apart from one another, counter to the resistance of the pin which is connected to the swash plate.
FIGS. 3 a to 3 d show different views of a preferred embodiment of the adjustment device 1 according to the invention. The pointer 3 engages, on one side of its pivot axis 5 , in the control piston 2 , and on the other side with the cylindrical pointer head 14 , between the spring levers 6 , 6 ′ and rests there on the coated bearing faces 11 , 11 ′. The spring levers 6 , 6 ′ and pointer 3 are each mounted directly on the eccentric part 9 of the axial bolt 8 . The spring levers 6 , 6 ′ are bent, each engage on the opposite side of the pointer 3 before the pivot axis 5 and each form a bearing shell 15 , each of which is composed in turn of two separate component shells between which the pointer 3 is held. The bearing shells 15 each enclose, with the exception of an angular region which is necessary for sufficient spreading of the spring levers, a half-space about the pivot axis 5 . This results in a very symmetric arrangement in which the spring levers 6 , 6 ′ can hardly tilt at all because they are each supported on the pivot axis at two locations by means of the divided bearing shells 15 .
Further embodiments of a largely tilt-free means of bearing the spring levers 6 , 6 ′ and pointer 3 are shown in FIGS. 4 and 5 in a similar representation to that in FIG. 3 and with the same reference symbols.
In the embodiment according to FIG. 4 , the spring levers 6 , 6 ′ each engage around both sides of the pointer 3 in a symmetrical arrangement in the region of the pivot axis 5 , the bearing of each spring lever 6 , 6 ′ being supported at two locations on the eccentric part 9 of the axial bolt 8 , in the manner of a fork, on both sides of the pointer 3 . In the embodiment according to FIG. 5 , the pointer 3 is embodied in the region of the pivot axis 5 as a fork so that it is mounted on the eccentric section 9 of the axial bolt 8 at two locations. The bearing shells of the spring levers 6 , 6 ′ are arranged between the two bearings of the pointer 3 . In the cases shown in FIGS. 3 to 5 , in each case a symmetrical arrangement which is very resistant to tilting is obtained, the pointer engaging in each case centrally between the spring levers.
One particularly advantageous refinement of the adjustment device is shown by FIG. 6 . The pointer 3 is not mounted directly on the eccentric section 9 of the axial bolt 8 here but rather on the spring levers 6 , 6 ′. This reduces the frictional forces because the pointer 3 inevitably always follows the movement of one of the spring levers.
The invention results in an adjustment device which is a very compact construction, can be adjusted precisely and is resistant to tilting, it being possible to cover an entire series of axial piston machines with different volumetric displacements using one and the same adjustment device. | An axial piston machine having a swash plate or oblique axis which can be adjusted by means of servopistons and has a valve segment and an adjustment unit for the electrically proportional adjustment of the volumetric displacement, the adjustment unit comprising proportional magnets which can be activated electrically, and a control piston for controlling the oil pressure which moves the servopistons, the proportional magnets acting on this control piston along a common tappet axis. A feedback device for feeding back the current swash plate or oblique axis valve segment position is provided. The feedback device comprises spring levers and a pointer which can be pivoted about an axis, the pointer which is embodied as a two-armed lever engaging in the control piston on one side of the pivot axis, and between the spring levers on the other side. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a twin wire former for the production of a fiber web, specifically a paper, cardboard or tissue web, from a fiber suspension. This type of twin wire former is generally referred to as “Roll-Blade-Former” in the industry.
2. Description of the Related Art
A twin wire former of this type for the production of a paper web, specifically a fine paper web, is already known from the PCT-disclosure document WO 97/47803. The disclosed twin wire former includes an upstream headbox with several separation elements in its headbox nozzle, and a forming roll, preferably a suction type forming roll, having a roll diameter of ≧1.4 m and an angle of wrap of <25°. In a curved twin wire zone located downstream from the forming roll, there are also methods for the introduction of pulsating pressure effects into the paper web that is being formed.
Further, a twin wire former as mentioned above, for the production of a paper web, specifically SC paper, is also known from the European patent application EP 0 627 523 A1. Here, initial dewatering of a fiber suspension occurs on a first forming roll in a forming zone. The fiber suspension is then brought onto a curved forming shoe, having a radius of 2 m to 8 m and is further dewatered. Subsequently, at least one dewatering unit including dewatering methods is located in the line. At the end zone of the twin wire zone there is a second forming roll including at least one suction zone, where the top wire of the twin wire former is separated from the forming paper web and is led away by way of a guide roll.
The two aforementioned twin wire formers have in common that the dewatering accomplished on the forming roll or in the area of the forming zone is greater than 70%. Since considerable portions of the paper web are formed without the presence of pressure pulsations, a forming quality that is only average is unavoidable when running fiber stock suspensions that are difficult to form. It is also a disadvantage that both twin wire formers have a very long open jet distance (distance: headbox nozzle to jet impact point), for example longer than 400 mm. This has a negative effect on the web quality, in machine direction (MD) as well as in machine cross direction (CD).
In order to achieve optimum sheet quality, a certain level of forming strip dewatering is particularly important. This requires very precise dimensioning of the forming angle, since large volumes are dewatered per angle degree. The optimum forming roll wrap must generally be determined during pilot trials, which are expensive and time intensive. Since the angle of wrap must always be matched to paper type, web weight and machine speed, even a small change in any one parameter causes extensive effects, which then will have to be neutralized at great expense.
If the sheet formation system is required to accommodate a larger weight range (specific production volume P), which is always the case with production lines, then the operating point abandons the optimum operating range on product changes. In the instance of the aforementioned twin wire formers, the fiber stock suspension throughput through the headbox must then be increased detrimentally in order to regain the optimum operating window.
The present invention provides an improved twin wire former to such an extent that the aforementioned disadvantages of the state of the art are avoided. A second objective is that fiber stock suspensions having a high long fiber content which makes them particularly difficult to form, for example papers, may find optimum use.
SUMMARY OF THE INVENTION
Characteristics of the present invention include:
the rotating forming roll has an open volume (storage volume) and is a non-suction type,
the rotating forming roll has a roll diameter of less than 1,400 mm,
the rotating forming roll has an angle of wrap of less than 7°,
a forming suction box is located immediately downstream from the rotating forming roll as viewed in the direction of wire travel, and
in the area of the wedge-shaped inlet nip, the fiber suspension has a stock consistency of between 0.4% and 2.0%, preferably between 0.6% and 1.5%.
By combining these characteristics in a twin wire former, the initial dewatering (dwell time) on the forming roll, or the dewatering volume is reduced to a minimum, whereby the minimum is smaller than 30% relative to the headbox throughput of a fiber stock suspension having a stock density of between 0.4% and 2.0%, preferably between 0.6% and 1.5% in the area of the wedge-shaped inlet nip. This is achieved by the maximum forming roll diameter of 1,400 mm and by the maximum forming roll angle of wrap of 7°. The maximum forming roll diameter of 1,400 mm and the maximum forming angle of wrap of 70 cause a greatly reduced dwell time on the forming roll.
Moreover, the minimum initial dewatering on the forming roll ensures a non-critical positioning of the headbox jet.
The headbox in whose nozzle—at least one machine-wide separation element, specifically a plate—is located produces a high quality headbox jet. In accordance with the present invention, this allows and even favors utilization in the twin wire former, of fiber stock suspensions having a high long fiber content (for example paper) which are particularly difficult to form.
The surface of the forming roll having the “open volume” is grooved and/or drilled and/or deflected, or is constructed in a honeycomb design. These configurations are cost effective to produce and do not influence the rigidity or the operational safety of the forming roll negatively, which, depending upon the application may be up to 10 m wide.
In order to considerably increase the dewatering capacity of the twin wire former of the present invention, at least one additional forming suction box must be located following the forming suction box as viewed in direction of wire travel.
In order to achieve as symmetrical a web quality as possible, the forming suction boxes are located opposite each other, whereby the forming suction boxes, as viewed in the direction of wire travel, may have some distance between them.
Under technological and qualitative aspects it is advantageous if the at least one forming suction box has a curved suction surface having a radius of curvature of 1,500 mm to 10,000 mm, preferably of 2,000 mm to 5,000 mm.
At least one forming suction box includes at least one suction chamber, whose vacuum is adjustable/controllable by way of a controllable vacuum source. This permits, and even enhances considerably the adjustment of optimum operating conditions in the area of the forming suction box.
In order to once more increase the dewatering capacity of the twin wire former in accordance with the present invention, while maintaining good web qualities, a multitude of forming strips are located opposite at least one forming suction box. In accordance with the present invention at least one of the forming strips is mounted flexibly and/or at least one of the forming strips is mounted stationary, whereby their base position is adjustable relative to their wire, for example by way of sliding or pivoting.
Additionally, at least one wet suction box is located downstream from at least one forming suction box as viewed in the direction of wire travel. Preferably, the wet suction box is supplied with vacuum, whereby the vacuum is adjustable/controllable by way of a controllable vacuum source. This permits, and even considerably enhances, the adjustment of optimum operating conditions in the area of the wet suction box.
In order to keep the spatial dimensions of the twin wire former according to the present invention as small as possible, a turning roller is located prior to the separation element as viewed in the direction of wire travel, thereby reducing the actual horizontal and/or vertical length of the twin wire zone to a certain degree.
In order to permit further processing of the fiber web that is supported on the wire after the separation from the top and bottom wires, at least one flat suction box and a suction couch roll are located after the separating element as viewed in the direction of travel of the wire. This allows the degree of dewatering of the fiber web to be increased further.
When using wood-free fiber suspensions it is also advantageous if at least one machine-wide separating element, specifically a plate, is located in the nozzle of the headbox.
In a first embodiment, the twin wire zone of the twin wire former according to the present invention can essentially rise vertically from the bottom to the top, preferably with a vertical excursion of −15° to +15°, preferably from −5° to +5°; and in a second configuration can rise from the bottom to the top with an incline from the horizontal plane of approximately 5° to 45°. In another embodiment, the twin wire zone can slope from the top to the bottom with sloping gradient in the end zone. These embodiments represent the known possibilities in accordance with the state of the art, and have proven themselves frequently in the field.
It is understood that the aforementioned characteristics of the invention, which will be explained in further detail below, may be utilized not only in the cited combinations but also in other combinations, or freestanding, without abandoning the scope of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention will be better understood by reference to the following description of embodiments of the invention taken in conjunction with the accompanying drawings, wherein:
FIG. 1 is a schematic side view representation of a first embodiment of the twin wire former of the present invention;
FIG. 2 is a schematic side view representation of a second embodiment of the twin wire former of the present invention;
FIG. 3 is a schematic side view of a third embodiment of the twin wire former of the present invention;
FIG. 4 is a schematic side view of a fourth embodiment of the twin wire former of the present invention;
FIG. 5 is a diagram of the operation performance for fiber suspension in a conventional Roll-Blade-Former concept; and
FIG. 6 is an enlarged version of the optimum operating window of the operating performance for fiber suspension in a conventional Roll-Blade-Former concept.
Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate one preferred embodiment of the invention, in one form, and such exemplifications are not to be construed as limiting the scope of the invention in any manner.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawings, and more particularly to FIG. 1, there is shown a first embodiment of the twin wire former 1 in accordance with the present invention. Two continuous wires (bottom wire 2 and top wire 3 ) together form a twin wire zone 5 . In an initial area of the twin wire zone 5 in which the two wires 2 , 3 run over a dewatering element which is in the embodiment of a rotating forming roll 6 , the two wires 2 , 3 together form a wedge-shaped inlet nip 7 (“Gap-Former”) at the forming roll 6 . The nip directly accepts the fiber suspension 9 from a headbox 8 which is located at an angle toward the left and top and which is illustrated only in part. In a central area of the twin wire zone 5 the two wires 2 , 3 together with the fiber web 4 which is forming between them, run over a multitude of additional dewatering and forming elements 10 . In an end area of the twin wire zone 5 , viewed in direction of wire travel S (arrow), the two wires 2 , 3 run over a separating element 11 which is in the embodiment of a suction couch roll 12 , which separates the top wire 3 from the formed fiber web 4 and from the bottom wire 2 .
According to the present invention rotating forming roll 6 has an open volume (storage volume) and has no suction. The rotating forming roll 6 according to the present invention also has a diameter DF smaller than 1,400 mm and a forming angle of wrap a smaller than 7°. Moreover, provisions are made in accordance with the present invention that a forming suction box 15 . 1 is located immediately following the rotating forming roll 6 , viewed in the direction of wire travel S, preferably on the same side as the forming roll. In the area of the inlet nip 7 the fiber suspension 9 has a stock consistency according to the present invention of between 0.4% and 2.0%, preferably between 0.6% and 1.5%.
The open volume of the forming roll 6 is such that its surface is grooved and/or drilled and/or deflected or is constructed in a honeycomb design. An additional forming suction box 15 . 2 is also located downstream from the first forming suction box 15 . 1 , as viewed in the direction of wire travel S, whereby the forming suction boxes 15 . 1 and 15 . 2 are located opposite each other and at a distance from each other. The forming suction boxes 15 . 1 , 15 . 2 have a curved suction surface 16 having a radius of curvature R K (arrow) of 1,500 mm to 10,000 mm, specifically of 2,000 mm to 5,000 mm.
The first forming suction box 15 . 1 includes at least one suction chamber 17 . 1 , the second forming suction box 15 . 2 includes two suction chambers 17 . 21 , 17 . 22 whose vacuums are adjustable/controllable by means of controllable vacuum sources 18 . 1 , 18 . 2 .
In accordance with the present invention a multitude of forming strips 19 are located opposite the first suction chamber 17 . 21 of the second forming suction box 15 . 2 . At least one of the forming strips 19 is mounted flexibly, or at least one of the forming strips 19 is mounted stationary, whereby their base positions are adjustable relative to the top wire 3 , for example by means of sliding or pivoting.
Additionally, the headbox 8 includes a headbox nozzle 13 in which at least one machine-wide separating element 14 , specifically a plate, is located. Two separating elements 14 are depicted in FIG. 1 . This separating element 14 may be divided into sections across the machine width and its effective length may be designed to be movable within the headbox nozzle 13 by way of a mechanism including a control unit. Utilization of at least one separating element 14 is recommended, particularly when using wood-free fiber suspensions.
The twin wire zone 5 of the twin wire former 1 covered by the present invention, as viewed in the direction of wire travel S, essentially rises vertically from the bottom to the top, whereby the vertical excursion Av from the vertical plane V assumes a value of −15° to +15°, preferably from −5° to +5°.
A schematic side view of a second embodiment, which is similar to the first embodiment of the twin wire former 1 , according to the present invention, is shown in FIG. 2 . We hereby refer to FIG. 1 for reference.
The present invention provides that a wet suction box 20 which is effective on the top wire 3 is located downstream from the first forming suction box 15 . 1 which is effective on the bottom wire 2 as viewed in the direction of wire travel S. The forming suction box 15 . 1 includes three suction chambers 15 . 11 , 15 . 12 15 . 13 , whereby the vacuum is controlled by way of an adjustable vacuum source 18 . 3 . In contrast, the wet suction box 20 includes only one suction chamber 20 . 1 which is supplied with vacuum, whereby the vacuum is controlled by way of an adjustable vacuum source 18 . 4 . A multitude of forming strips 19 are located opposite the forming suction box's 15 . 1 three suction chambers 15 . 11 , 15 . 12 , and 15 . 13 . The headbox 8 , which is illustrated only partially in FIG. 2, does not contain a machine wide separation element, specifically a plate.
FIGS. 3 and 4 illustrate schematic side views of a third and fourth embodiment of the twin wire former 1 according to the present invention. Since the configurations are again similar in principal to the embodiment in FIG. 1, we refer you to FIG. 1 for reference.
Both FIG. 3 and FIG. 4 provide, according to the present invention, that the twin wire zone 5 , as viewed in the direction of wire travel S, rises from the bottom to the top with an incline N from the horizontal plane H of approximately 5° to 45°. In FIG. 3 the headbox 8 which is illustrated only partially, is located at an angle toward the right bottom and in FIG. 4 at an angle toward the right top. The twin wire formers 1 in both FIG. 3 and FIG. 4 show two forming suction boxes 15 . 1 , 15 . 2 which are located immediately downstream from the rotating forming roll 6 , as viewed in the direction of wire travel S. FIG. 3 illustrates a forming suction box 15 . 1 located on the bottom wire 2 , followed by a forming suction box 15 . 2 located on the top wire 3 , with forming strips 19 located opposite it. In contrast, FIG. 4 shows an arrangement whereby a suction forming box 15 . 1 is first located on the top wire 3 , with forming strips 19 located opposite it, followed by a forming suction box 15 . 2 located on the bottom wire.
In FIG. 3 a turning roller 21 is located downstream from the second forming suction box 15 . 2 , as viewed in the direction of wire travel S, which allows the twin wire zone 5 to slope from top to bottom in the end zone. A separating element 11 in the embodiment of a transfer suction box 22 which separates the top wire 3 from the formed fiber web 4 , and from the bottom wire 2 is located following the turning roller 21 . A flat suction box 23 and a suction couch roll 12 are located following the transfer suction box 22 . At a downstream pick-up roll 25 the fiber web 4 is taken from the bottom wire 2 by a felt 24 and is transferred to the subsequent manufacturing process.
In FIG. 4 a separating element 11 in the embodiment of a suction couch roll 12 is located downstream from the second forming suction box 15 . 2 as viewed in the direction of wire travel S. This separates the top wire 3 from the formed fiber web 4 and from the bottom wire 2 .
FIG. 5 is a diagram of the operating performance for fiber suspensions in a conventional Roll-Blade-Former concept. The abscissa indicates the throughput D S of fiber suspension through the headbox in [1/(min·m)], the ordinate indicates the forming shoe dewatering E F in [1/(min·m)]. The throughput D S assumes a value range of 8,500 [1/(min·m)] (left terminating straight line) to 18,380 [1/(min·m)] (right terminating straight line), while the forming shoe dewatering E F assumes a value range of 600 [1/(min·m)] (bottom terminating straight line) to 2000 [1/(min·m)] (top terminating straight line). The terminating straight lines provide an operating window in which the Roll-Blade-Former can be operated along a curve K (bold print) with good results within a wider weight range (specific product volume P). Very good results are achieved with the Roll-Blade-Former, for example with a view to sheet formation, within an optimum operating window Af opt. which is defined by the following terminating straight lines: throughput D S with the terminating straight lines at 15,000 [1/(min·m)] and 18,380 [1/(min·m)], and forming shoe dewatering E F at 1,300 [1/(min·m)] and 1,800 [1/(min·m)].
FIG. 6 illustrates an enlarged version of the optimum operating window Af opt ., whereby the operating point AP is in the optimum operating window Af opt . On product changes the operating point AP leaves the optimum operating window Af opt . (vertical down arrow) and is placed on the curve K′ (broken line) outside the operating window A F , providing poorer results. With the known and aforementioned twin wire formers the fiber suspension throughput D S through the headbox must then be increased in a negative way (upward arrow, angled toward right) in order to return to the optimum operating window.
In summary it can be said that the present invention of a twin wire former provides, that the aforementioned disadvantages of the state of the art are completely avoided and that fiber suspensions containing long fibers which are particularly difficult to form, for example papers, can be put to optimum use.
While this invention has been described as having a preferred design, the present invention can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims. | The invention relates to a twin wire former for the production of a fiber web specifically a paper, cardboard or tissue web, from a fiber suspension. The invention is characterized in that
the rotating forming roll has an open volume and is a non-suction type;
the rotating forming roll has a forming roll diameter of less than 1,400 mm;
the rotating forming roll has a forming roll angle of wrap of less than 70°;
a forming suction box is located immediately downstream from the rotating forming roll as viewed in direction of wire travel; and
in the area of the wedge-shaped inlet nip, the fiber stock suspension has a stock density of between 0.4% and 2.0%, preferably between 0.6% and 1.5%.
These characteristics result in an improved forming quality and web quality. | 3 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of U.S. Provisional Patent Application Ser. No. 60/907,196, filed Mar. 26, 2007.
BACKGROUND OF THE INVENTION
[0002] 1. Filed of the Invention
[0003] The present invention relates to construction tools, and more particularly to a multipurpose sawhorse end frame that can be configured into a sawhorse, scaffolding, workbench, table, or other temporary structure.
[0004] 2. Description of the Related Art
[0005] During the construction of buildings or other projects, it is often necessary to support boards so that the boards can be cut with a portable saw, such as a jig saw or portable circular saw. Similarly, it may become necessary to use scaffolding so that the construction worker can reach windows, roof gutters, and the like from the exterior of the building or other structure. The construction worker may also find a workbench or table useful for supporting tools, boards, fasteners, and other tools or workpieces that may be required during the construction project.
[0006] The transport and setup of so many accessories can become both burdensome and time-consuming. Therefore, there is a need for a single accessory that can be configured into any of the desired accessories with the use of boards or scrap lumber that would otherwise be disposed of, and which can be quickly set up and broken down for compact storage and transport. Thus, a multipurpose sawhorse end frame solving the aforementioned problems is desired.
SUMMARY OF THE INVENTION
[0007] The multipurpose sawhorse end frame has a top section defining center and lateral slots for receiving 2″×4″ beams and central slots for 2″×12″ planks, a central section with center slots for receiving 2″×4″ beams and lateral support bars for supporting 2″×12″ planks, and a bottom section having feet for supporting the frame. A plurality of diagonal braces maintain rigidity of the end frame and provide the end frame with structural strength. Two or more end frames may be configured as a sawhorse, a scaffold, a workbench, a table, or other temporary construction accessory using scrap lumber and without fasteners. The multipurpose sawhorse end frame may be made from lightweight aluminum or other suitable material.
[0008] These and other features of the present invention will become readily apparent upon further review of the following specification and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is front view of a multipurpose sawhorse end frame according to the present invention.
[0010] FIG. 2 is an environmental perspective view of a pair of multipurpose sawhorse end frames according to the present invention configured as a sawhorse with center support.
[0011] FIG. 3 is an environmental perspective view of a pair of the multipurpose sawhorse end frames according to the present invention configured as a sawhorse.
[0012] FIG. 4 is an environmental perspective view of a pair of the multipurpose sawhorse end frames according to the present invention configured as a mid-duty scaffold.
[0013] FIG. 5 is an environmental perspective view of a pair of the multipurpose sawhorse end frames according to the present invention configured as a heavy-duty scaffold.
[0014] FIG. 6 is an environmental perspective view of a pair of the multipurpose sawhorse end frames according to the present invention configured as a cantilever work support.
[0015] FIG. 7 is an environmental perspective view of a pair of the multipurpose sawhorse end frames according to the present invention configured as a worktop with seat.
[0016] FIG. 8 is an environmental perspective view of a pair of the multipurpose sawhorse end frames according to the present invention configured as a two-stage scaffold or workbench with seat.
[0017] Similar reference characters denote corresponding features consistently throughout the attached drawings.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0018] The present invention is a multipurpose sawhorse end frame that can be easily assembled or disassembled and reconfigured for a variety of purposes. A sawhorse or trestle can be erected using a pair of the end frames 200 , which are constructed from ¼4″×2″ aluminum stock, and scrap lumber for the beams. As best seen in FIG. 1 , the end frame 200 has a top section 201 having an elongated horizontal top bar 206 and an elongated horizontal bottom bar 207 . Vertical bars 208 , 209 and 210 are welded to the top bar 206 and bottom bar 207 at a first end to form a first pair of lateral slots 211 and 212 for receiving 2″×4″ beams. Vertical bars 213 , 214 and 215 are welded to middle portion of the top bar 206 and bottom bar 207 to form a pair of center slots 216 and 217 for receiving 2″×4″ beams. Vertical bars 218 , 219 and 220 are welded to the second end of top bar 206 and bottom bar 207 to form another pair of lateral slots 221 and 222 for receiving 2″×4″ beams.
[0019] A horizontal bar 223 is welded to vertical bars 210 and 213 to form a pair of central slots 224 and 225 , respectively, for receiving 2″×12″ planks. Another horizontal bar 226 is welded to vertical bars 215 and 218 to form another pair of central slots 227 and 228 , respectively, for receiving 2″×12″ planks.
[0020] A first leg bar 203 is welded at its upper end to the first end of the top section 201 and welded at a lower end to a diagonal brace 243 . A second leg bar 204 is welded at an upper end to the second end of the top section 201 and welded at a lower end to a diagonal brace 244 . An elongate base bar 202 is welded at a first end to a lower portion of first leg bar 203 a predetermined distance from diagonal brace 243 . Base bar 202 is welded at a second end to a lower portion of second leg bar 204 a predetermined distance from diagonal brace 244 . Base bar 202 is longer than the top section 201 so that leg bars 203 and 204 extend outwardly at a slight angle.
[0021] A vertical center bar 205 is welded at an upper end to the center of bottom bar 207 of top section 201 and welded at a lower end to the center of base bar 202 . A top wall 229 and bottom wall 230 are welded to a sidewall 231 and to the center bar 205 adjacent the center of the center bar 205 to form a center slot 232 in a central section of the end frame 200 for receiving a 2 ″× 4 ″ beam. A top wall 233 and bottom wall 234 are welded to a sidewall 235 and to the center bar 205 adjacent the center of the center bar 205 to form a second center slot 236 in the central section for receiving a second 2″×4″ beam.
[0022] A top end of a first diagonal brace bar 237 is welded to a first end of bottom bar 207 . A bottom end of first diagonal brace bar 237 is welded to one end of top wall 229 . A top end of a second diagonal brace bar 238 is welded to a second end of bottom bar 207 . A bottom end of second diagonal brace bar 238 is welded to one end of top wall 233 . A top end of a third diagonal brace bar 239 is welded to one end of bottom wall 230 . A bottom end of brace bar 239 is welded to base bar 202 adjacent to a first end of the base bar 202 . A top end of a fourth diagonal brace bar 240 is welded to one end of bottom wall 234 . A bottom end of brace bar 240 is welded to the base bar 202 adjacent to a second end of the base bar 202 .
[0023] Fifth diagonal brace 243 is welded at a top end to the base bar 202 adjacent to the first end of the base bar 202 and welded at a bottom end to the center of footplate 245 in the bottom section of the end frame 200 . Sixth diagonal brace bar 244 is welded at a top end to the base bar 202 adjacent the second end of base bar 202 and welded at a bottom end to the center of footplate 246 .
[0024] A first horizontal support bar 241 is welded at a first end to a center portion of first leg bar 203 and welded at a second end to the center of sidewall 231 . A second horizontal support bar 242 is welded at a first end to the center of sidewall 235 and welded at a second end to a center portion of second leg bar 204 .
[0025] To configure the end frame 200 as a sawhorse with a center support, a pair of end frames 200 are provided with 2″×4″ beams in slots 210 , 211 , 216 , 217 , 221 and 222 , as best seen in FIG. 2 . A panel 253 may be supported upon the planks, either as a workpiece or to serve as the worktop.
[0026] In FIG. 3 , the end frames 200 are shown configured as a sawhorse, trestle, or for light duty scaffolding, where the 2″×4″ beams are placed in slots 211 , 222 and 235 . Panel 253 may be placed upon the upper sawhorse to serve as a scaffold.
[0027] FIG. 4 shows the sawhorse end frames 200 configured for medium-duty scaffolding. Beam 250 is place in slot 211 , beam 251 is placed in slot 217 , beam 252 is placed in slot 222 and beam 254 is placed in slot 236 . Panel 253 is placed upon the upper planks to serve as the scaffold platform.
[0028] In FIG. 5 , beam 255 is placed into slots 216 of a pair of end frames 200 , beam 256 is placed in slots 217 , beam 259 is placed in slots 232 , while 2″×12″ plank 257 is placed in slots 224 and 2″×12″ plank 258 is placed in slots 227 to form a heavy duty scaffold.
[0029] In FIG. 6 , 2″×4″ beams 260 , 261 and 262 are passed through slots 211 , 217 and 222 , respectively, of a pair of end frames 200 and a panel is place on the extended portion of the planks to form a cantilevered work support.
[0030] In FIG. 7 , 2″×4″ beams 264 and 265 are placed in slots 211 and 222 . A panel 253 is place upon the beams 264 and 265 to serve as a worktop. A 2″×12″ plank is laid across horizontal support bars 242 to serve as a tool storage area.
[0031] In FIG. 8 , 2″×4″ beams 266 and 267 are placed in slots 212 and 216 , respectively, and a 2″×12″ plank 268 is placed in slots 224 . A 2″×12″ plank 269 is laid across horizontal support bars 242 . In this configuration the sawhorse end frames 200 serve as a two-stage scaffold or a tabletop and bench for an eating area.
[0032] It will be noted that the provision of side-by-side or double slots 210 and 211 , 216 and 217 , 221 and 222 , and 232 and 236 effective allow two 2″×4″ beams to placed side-by-side whenever a 4″×4″ beam is needed to support a load. It will be noted that the recitation of particular dimensions is exemplary, and not by way of limitation. In particular, the end frame may have slots dimensioned to accommodate, e.g., 2″×6″ beams and planks from 2″×8″ to 2″×12″, if desired.
[0033] It is to be understood that the present invention is not limited to the embodiment described above, but encompasses any and all embodiments within the scope of the following claims. | The multipurpose sawhorse end frame has a top section defining center and lateral slots for receiving 2″×4″ beams and central slots for 2″×12″ planks, a central section with center slots for receiving 2″×4″ beams and lateral support bars for supporting 2″×12″ planks, and a bottom section having feet for supporting the frame. A plurality of diagonal braces maintain rigidity of the end frame and provide the end frame with structural strength. Two or more end frames may be configured as a sawhorse, a scaffold, a workbench, a table, or other temporary construction accessory using scrap lumber and without fasteners. The multipurpose sawhorse end frame may be made from lightweight aluminum or other suitable material. | 4 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation application of U.S. patent application Ser. No. 10/149,426, filed on Jun. 24, 2002.
BACKGROUND
[0002] 1. Field of the Invention
[0003] The invention relates to weaving machine heald frame fitted with an upper and a lower cross-sectionally contoured rail, hereafter rail, for holding the healds which are held by guide elements located at the ends of the healds to the rails.
[0004] 2. Related Art
[0005] Several heald frames of this kind constitute a so-called heald frame system. The individual heald frames of this system are alternatingly raised and lowered by a heald frame machine in order to form sheds using heald-guided warps between which fillings may be inserted. The rails and the heald guide elements typically have geometries such that, in one direction of heald frame motion, one of the rails rests by a drive surface against a cooperating surface of the heald guide elements to thereby drive such healds. In the other direction of motion, a drive surface of the other rail will drive a cooperating surface of the heald guide elements which are associated with it. Because the heald frames and the healds expand on account of heat and forces applied by the warps, and because manufacturing tolerances have to be provided for both, and because additionally the healds must be displaceable along the rails, for instance to insert or repair warps, a play of about 2-3 mm is provided for the healds between the drive surfaces of the rails and the cooperating surfaces of the guide elements. When the frames move up and down, the healds will move by said 2-3 mm relative to the rails. These motions result in impacts causing on one hand noise and on the other hand heald vibrations. At high weaving rates, these motions and particularly the thereby caused vibrations may break the healds and/or the heald frames and/or the warps.
[0006] To avoid such problems, it is known from WO 97/23396 to reduce the play between the healds and the rails by providing one or more shims fitted onto one of the rails to reduce the gap between these heald drive surfaces of this rail and the cooperating surfaces of the heald guide elements down to a slight play of about 1 mm. These shims are made of plastic, and consequently damping is attained as ell. In this manner noise and the risk of damage may be reduced, although some drawbacks may be incurred regarding operability. Because the heald play is reduced longitudinally, the longitudinal movability of the healds and their movability in the direction of the rails also is restricted. As a result, an operator repairing a yarn break may be somewhat hampered and it is even possible that the healds could be bent in the course of making repairs.
BRIEF SUMMARY OF THE INVENTION
[0007] The objective of the present invention is the reduction of noise and furthermore the reduction of potential damage caused by heald vibration.
[0008] This problem is solved in that a damping stop made of material with damping properties is provided adjacent at least one end of the healds and in that the gap between this stop and the adjacent end of the healds shall be smaller than the gap between the guide element ends and the rail surfaces opposite the stop.
[0009] In this design the healds shall be driven at least in one direction by the damping stop or they shall impact the stop in one direction, as a result of which noise will be significantly reduced. Also, at least when the healds are driven in one direction or when impacted in one direction, damping shall take place and heald vibrations will be substantially reduced. This reduction in noise and adverse effect of vibrations also shall be the case for plays of larger magnitudes, for instance of 2-3 mm or more, and consequently there would be no restriction on the relative movability of the healds in the longitudinal rail direction or in their own longitudinal direction. Means are thus provided to the skilled designer to reduce the danger of noise and creaking movability or shiftability by controlling the play or to trade off somewhat more noise and somewhat greater danger of vibrations against improved heald movability.
[0010] Preferably stops shall be fitted at both heald ends. In this manner driving of the healds and the impact of the healds on drive elements takes place solely against the damping stops. The rails in accordance with this design merely provide lateral guidance. Consequently the longitudinal heald play may be selected almost arbitrarily, that is, it may be comparatively small and entail less movability and longitudinal excursion, or it may be comparatively large with commensurately good movability and longitudinal excursion.
DESCRIPTION OF THE DRAWINGS
[0011] Further features and advantages of the invention are elucidated in the description below of the illustrative embodiments shown in the attached drawings.
[0012] FIG. 1 is a schematic front view of a heald frame of the invention,
[0013] FIGS. 2, 3 are cross-sections along line II-II of FIG. 1 in different frame positions, and
[0014] FIGS. 4, 5 are cross-sections similar to FIGS. 2, 3 of a modified embodiment with a unilateral stop
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0015] The heald frame 1 shown in FIG. 1 is a frame consisting of two supporting side sidebars 2 and 3 and two supporting crossbars 4 , 5 . Rails 6 , 7 are affixed by brackets 8 in the zone of the mutually facing sides of the supporting crossbars 4 , 5 . These rails 6 , 7 receive lamellar healds 10 each fitted centrally with a yarn eyelet 12 to receive a warp. The healds 10 are guided by guide elements 13 , 14 on the rails 6 , 7 . The rails 6 , 7 are fitted for example at their longitudinal ends with limit stops 11 to prevent the healds 10 from slipping off. The rails include opposed ends located respectively towards and away from the cross bars to which they are attached, said rail ends facing adjacent guide ends defining the limits of play between the rails and the guides, in a well known manner.
[0016] The ends of the healds 10 are associated with strip shaped heald stops 15 , 16 mounted on the crossbars 4 , 5 and which drive the healds 10 in the manner described below in relation to FIGS. 2 and 3 . The guide elements 13 , 14 of the lamellar healds 10 are dimensioned in such a way relative to the rails 6 , 7 that the rails 6 , 7 shall guide the healds 10 only laterally, but will not drive the healds via their ends during lifting and lowering movements. The brackets 8 of the rails 6 , 7 are fastened by screws 9 to the crossbars 4 , 5 , said screws passing through slots 17 of the brackets 8 ( FIGS. 2, 3 ) running in the longitudinal direction of the healds 10 . In this way the position of the rails 6 , 7 is adjustable in the longitudinal direction of the lamellar healds 10 relative to the crossbars 4 , 5 .
[0017] When the heald frame is raised in the direction of the arrow A at the middle shed position, or when it is at its upper end position, then the lower ends of the healds 10 shall rest against the lower damping stop 16 as shown in FIG. 2 . When the frame is lowered in the direction of the arrow B as indicated in FIG. 3 , then the healds 10 if in the middle shed position will reverse their relative position and will come to rest by their upper end impacting against the upper damping stop 15 . Because the stops 15 , 16 are made of a damping synthetic material, the impulse will be decelerated and damped and on one hand the noise shall be much abated, while on the other hand the danger of damage caused by vibrations in the heald 10 is reduced. If then the frame is raised again in the direction of the arrow A as shown in FIG. 2 , the healds shall on the basis of the warp tension again reverse their position in a substantially impulsive manner in the middle shed zone, and thereafter they will rest by their lower end against the lower stop 16 . Accordingly the healds 10 are moved as described and their longitudinal excursions are limited solely by means of the strip shaped damping stops 15 , 16 made of damping synthetic material. Therefore the play within which the healds 10 may be moved relative to the upper crossbar 4 and the lower crossbar 5 may be selected as a relatively large play without increasing the danger of more noise and/or damage. If a relatively large play is selected, it will be easier to shift the healds 10 along the longitudinal direction of the rails 6 , 7 and furthermore to shift them in their own longitudinal direction with respect to the rails 6 , 7 —this feature being advantageous for an operator repairing a warp break.
[0018] As regards the embodiment shown in FIGS. 2 and 3 , the upper crossbar 4 and the lower crossbar 5 are fitted with a seat 18 illustratively in the form of a longitudinal groove. The stops 15 , 16 are strips received in this seat 18 and are affixed for instance by bonding. Such a seat 18 is recommended for new heald frames in accordance with the invention. If on the other hand already extant heald frames are being retrofitted to correspond with frames made in accordance with the invention, other means may be used to mount the strip shaped stops 15 , 16 . Illustratively the latter may be mounted by fasteners to the crossbars 4 , 5 in such a way that they rest on the mutually opposite edges. Moreover affixing elements may be used that are affixed to but spaced from the crossbars 4 , 5 . In the latter case those sides of the strip shaped stops 15 , 16 which are located opposite the healds 10 shall be appropriately reinforced by a reinforcing rail.
[0019] As shown in the illustrative embodiment of FIGS. 4 and 5 , a substantial improvement is attained even if only one strip shaped stop 15 is used on one side, that is, as regards this embodiment, at the upper crossbar 4 . In this configuration and as shown in FIG. 4 , the healds 10 ′ are raised by a drive surface of the upper rail 6 , said drive surface being situated opposite a cooperating surface of the upper guide element 13 ′. In this embodiment, the lower rail 7 is used only to guide the heald 10 ′ transversely. In this embodiment of FIGS. 4 and 5 , the guide elements 13 ′, 14 ′ of the healds 10 ′ are open toward the brackets 8 and as a result the healds 10 ′ also may be freely displaced in the vicinity of the brackets 8 . As regards another embodiment, the rail 6 and its associated guide element 13 ′ are dimensioned in such a way that they will only be in the transverse guide mode while the healds 10 ′ are driven in a lifting direction by the lower rail 7 which then will rest by one drive surface against a cooperating surface of the guide element 14 ′. Obviously one stop only may be used also in the region of the lower ends of the healds 10 ′, for instance a stop 16 as shown in the embodiment of FIGS. 2 and 3 . | A heald frame for a weaving machine includes stops ( 15, 16 ) made of a material with shock-absorbing properties associated with the ends of the healds ( 10 ). A gap is provided between the heald ends and the stops, such gap ensuring that the healds can be moved along guide rails forming part of the heald frame while reducing noise and potentially damaging vibrations. The healds are held on the guide rails with play and are moved by and limited in their movements in a longitudinal direction by the stops. | 3 |
DESCRIPTION
Introduction
The invention relates to a process for the stereoselective preparation of trans-4-alkyl-cyanoarylcyclohexanes of the formula: ##STR1## in which R is an unbranched or singly branched aliphatic hydrocarbon radical of 1 to 12 carbon atoms and n is an integer in the range from 0 to 2.
The trans-4-alkyl-cyanoarylcyclohexanes corresponding to Formula (I) are capable of forming nematic liquid crystal phases. They are preferably used as components of liquid crystal mixtures, especially nematic liquid crystal mixtures.
The trans-4-alkyl-(4'-cyanophenyl)cyclohexanes and the trans-4-alkyl-(4"-cyanobiphenyl-4'-yl)cyclohexanes are known compounds.
The trans-4-alkyl-(4"'-cyanoterphenyl-4'-yl)cyclohexanes are new substances. As components of liquid crystal mixtures they have the capability of enlarging the range of existence of the meso phase and of improving its stability without significantly increasing the switching times of these mixtures.
The 4-alkyl-cyanoarylcyclohexanes exist in a cis form and a trans form. Only the trans form is usable as a liquid crystal or a component of a liquid crystal mixture.
PRIOR ART
A process for preparing trans-4-alkyl-(4'-cyanophenyl)cyclohexanes is disclosed in Angew. Chem. 89, 103. 4-Alkylcyclohexanone is converted to a mixture of the two cis-trans isomers of 4-alkyl-1-phenyl-cyclohexanol with phenyl magnesium bromide in diethyl ether. The isomeric mixture is separated in a chromatographic column and separately recovered. The trans isomers are hydrogenated with molecular hydrogen in the presence of a Raney nickel catalyst, the cis isomers in the presence of palladium on activated carbon. When hydrogenating the cis isomer, isomerization to the trans isomer takes place. Both of the resulting trans-4-alkyl-phenylcyclohexane fractions are combined, acetylated according to Friedel-Crafts, subjected to haloform degradation to carboxylic acid, converted to the acid amide and finally dehydrated to the nitrile with POCl 3 .
It is a disadvantage of this known process that the 4-alkylcyclohexanones are available only with difficulty, a chromatic separation of the difficultly separable cis-trans isomers of the cyclohexanols is required and the chromatographically separated isomers must then be separately hydrogenated.
OBJECTS
It is an object of this invention to provide a process for the stereoselective preparation of trans-4-alkyl-cyanoarylcyclohexanes of the kind described above, which is simple and economical. A more particular object is to provide such a process that is based on the use of readily accessible and relatively inexpensive starting materials and that does not require any separation and separate treatment of isomeric intermediates.
These and other objects as well as the nature and scope of this invention, will become apparent from the following description and appended claims.
GENERAL DESCRIPTION
The biphenyl-, terphenyl- or quaterphenyl-4-carboxylic acids that are required as starting materials in this process are commonly available in commerce. As is well known, the biphenyl-4-carboxylic acid is readily prepared from the corresponding 4-bromo derivative by the Grignard reaction while the higher polyphenyl carboxylic acids can be prepared, for instance, by conversion with organolithium as described by H. Gilman (J. Org. Chem. 22, 446).
According to the invention, the cyclohexane-4-carboxylic acid esters that are obtained as an isomeric mixture from the starting acid by hydrogenation and esterification with a lower alkanol, e.g., methanol, ethanol, isopropanol or tert-butanol, can be quantitatively isomerized to the stereochemically pure trans-arylcyclohexane-4-carboxylic acid alkyl ester, e.g., the ethyl ester, without requiring separation of the cis-trans isomers. This can be done by treatment of the ester mixture in an anhydrous alkanol, preferably in anhydrous ethanol, under an inert gas such as nitrogen or argon in the presence of sodium or potassium, preferably in the presence of about 10 mole percent sodium based on the esters to be treated. If in doing this a methyl ester mixture is isomerized instead of the ethyl ester mixture and absolute ethanol is used as the isomerization medium, a transesterification takes place such that the trans-ethyl ester is actually obtained because of the presence of absolute ethanol in this step.
The resulting trans-arylcyclohexane-4-carboxylic acid ethyl ester is readily saponifiable in an otherwise well-known manner. For instance, the saponification can be efficiently conducted by using lithium hydroxide monohydrate in ethanol solution, which is the preferred saponifying agent. However, other alkali metal and alkaline earth metal hydroxides in alcoholic solution can be used similarly.
The resulting trans-arylcyclohexane-4-carboxylic acid is subsequently subjected to chain growth in a conventional manner and the carbonyl group in the α-position is then reduced. The chain growth must be conducted at low temperatures, e.g., at below -20° C., preferably between -50 ° and -100° C., and most preferably at -70° C., in order to have it proceed stereospecifically. The reaction is conducted under absolutely anhydrous conditions, preferably in tetrahydrofuran and/or hexane. If the aromatic residue is a phenyl radical, one may perhalogenate, preferably percholorinate, the phenyl residue prior to the chain growth reaction, preferably prior to the saponification. The required dehalogenation can then take place either before or after reduction of the carbonyl group.
In selecting among the innumerable known processes for obtaining chain growth it is important to take heed that deprotonation of the cyclohexane in the 4-position is definitely precluded. The chain growth method using the reaction with alkyl lithium, which is preferred because of its good yields, proceeds quantitatively in a stereospecific manner. Suitable alkyl metal compounds include, for instance, methyl lithium, n-propyllithium, iso-propyllithium, n-butyllithium, n-undecyllithium and other similar unbranched or singly branched organic metal compounds containing 1 to 11 or 12 carbon atoms per alkyl group.
The subsequent reduction of the carbonyl group can be obtained in a well-known manner, for instance according to Clemmensen or Wolff-Kishner.
The trans-4-alkyl-arylcyclohexane obtained after such reduction corresponds to the trans-4-alkyl-phenylcyclohexane that is obtained as an intermediate product in the previously known process. The introduction of the cyano group can then take place the same way as has been done in the prior art, via acetylation and a haloform degradation with subsequent dehydration of the amide. It is preferable, however, to do so via the direct conversion of the trans-4-alkyl-arylcyclohexane in the presence of aluminum chloride with oxalyl chloride according to Friedel-Crafts, which surprisingly also proceeds quantitatively stereospecifically and with high yields. The obtained 4'-, 4"- or 4"'-acid chloride can then be converted to the nitrile in one step via the amide.
Naturally, instead of the cyano group in the p-position of the aryl residue one can introduce other groups as may be desired, especially ester groups. Likewise, instead of the chain growth and subsequent reduction of the carbonyl group in the 4-position of the cyclohexane one can perform other modifications, for instance an esterification or transesterification with an alcohol, as is otherwise well known and common in the art pertaining to the preparation of compositions for nematic liquid crystal phases.
PREFERRED EMBODIMENT
The invention is further illustrated by the following working example.
EXAMPLE
A total 6.0 g sodium , i.e., a source of solvated electrons, is added in small portions in the course of 60 minutes under nitrogen at -70° C. to 16.2 g (0.082 mol) of a commercially available biphenyl-4-carboxylic acid in 30 g absolute anhydrous ethanol, i.e., a proton donor, and 300 ml anhydrous ammonia (to provide solvated electrons). 50 g solid ammonium chloride and 70 ml cold water are added to the resulting suspension after completion of the reaction. Subsequently the ammonia is removed under reduced pressure. After dilution with an additional 30 to 50 ml water the mixture is extracted with 100 ml diethyl ether. Subsequently the mixture is acidified with concentrated hydrochloric acid and extracted three more times with ether. The combined ether phases are dried over magnesium sulfate and concentrated. In doing this 14.6 g of a white crystalline substance precipitates out that is identified as an isomeric mixture of cis- and trans-phenylcyclohexa-2,5-diene-4-carboxylic acid.
10 g (0.050 mol) of the obtained isomeric mixture is dissolved in 5 to 10 ml methanol and a catalytic amount of p-toluenesulfonic acid and 50 ml carbon tetrachloride are added. The mixture is heated for 10 hours under reflux at atmospheric pressure. After cooling and complete separation of the two phases the carbon tetrachloride phase is removed, concentrated and dissolved in anhydrous ethanol. Subsequently it is hydrogenated with hydrogen gas using a palladium/activated carbon catalyst. After consumption of the calculated amount of hydrogen the catalyst is removed by filtration. A few milliliters of benzene are added to the reaction mixture in order to remove even the last traces of water as an azeotrope. The thus dried reaction mixture is subsequently treated with 10 mole percent sodium under nitrogen and heated 48 hours under reflux at atmospheric pressure. Subsequently, the mixture is cooled, concentrated, mixed with water, neutralized and extracted several times with diethyl ether. The combined ether extracts are dried. The ether solvent is subsequently removed under reduced pressure. 10.5 g of practically pure, white trans-phenylcyclohexane-4-carboxylic ethyl ester is thus obtained.
10.0 g (0.043 mol) of the obtained stereochemically pure ester is dissolved in ethanol and 2.7 g (0.065 mol) lithium hydroxide monohydrate is added. After completion of the saponification the reaction mixture is neutralized with an ethanol solution of hydrochloric acid, concentrated, water is removed from it by azeotropic distillation upon addition of benzene and the product is suspended in tetrahydrofuran. The suspension is cooled to -70° C. and 0.043 mol n-butyllithium in hexane is added under nitrogen. The reaction mixture is stirred at this temperature for one hour. Thereafter the reaction mixture is removed from the cryostat and poured at room temperature into an ice/water mixture. The resulting mixture is neutralized, concentrated and taken up in dioxane. The obtained ketone is then directly reduced at room temperature without any prior isolation in the usual manner according to Clemmensen. After recrystallization 5.6 g of white trans-4-n-pentylphenylcyclohexane are obtained.
The cyano group can then be introduced into the 4'-position of the phenyl residue of the thus obtained substance according to the known technique described in Angew. Chem. 89, 103.
Alternatively, one can convert the obtained trans-4-n-pentylphenyl-cyclohexane in the presence of anhydrous aluminum chloride with oxalyl chloride to the corresponding 4'-acid chloride and subsequently convert it to the trans-4-n-pentyl-(4'-cyanophenyl)cyclohexane via the amide and by dehydration of the amide with POCl 3 . The trans-4-n-pentyl-(4'-cyanophenyl)cyclohexane has a melting point of 30 ° to 30.5° C. and a clear point of 55° C. The resulting compound exhibits nematic behavior such that the presence of the equatorial trans-form is presumed. | Trans-4-alkyl-cyanoarylcyclohexanes are prepared in a stereoselective manner from arylcarboxylic acids of the formula Ar-[Ar] n -Ar-4-COOH, Ar being aryl and n being 0 to 2, by first converting such a carboxylic acid to a mixture of the cis and trans isomers of the corresponding cyclohexa-2,5-diene-4-carboxylic acid, esterifying the resulting isomer mixture with a lower alkanol and further hydrogenating the resulting esters/isomers to produce the cis and trans isomers of the corresponding cyclohexane-4-carboxylic acid esters, isomerizing the cis isomers in the mixture to the trans isomer thereby producing a mixture containing the trans isomer substantially free from cis isomer, stereospecifically saponifying the trans isomer, growing a carbon chain of desired length on the carboxyl group of the resulting carboxylic acid, reducing the carbonyl group thereof, and introducing a cyano group into the terminal aryl group. The resulting product is useful as a nematic liquid crystal. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a pressure control system for an electromagnetic reciprocating pump, and particularly to a pressure control system for an electromagnetic reciprocating pump which can maintain the actual outlet pressure at a predetermined value.
2. Description of the Prior Art
Various proposals have so far been made to the structure of a compressor equipment. But, it is general to convert a rotating drive source to the linear reciprocating motion of a compressor piston through a crank mechanism, or to generate a pressurized fluid by connecting a rotating drive source to a rotation-type fluid compressing device. The former is accompanied by a large noise and vibration, and the overall structure becomes complex. The latter is excellent in noise and vibration, but the sealing is very difficult in the rotation-type fluid compressing device.
Also, outlet pressure control for these compressor equipments is typically on-off control, and it is difficult to perform an accurate pressure control with high precision.
In contrast to this, in an electromagnetic reciprocating pump using an electromagnetic drive means as the drive source, since the electromagnetic drive means itself performs a linear motion, a mechanism for converting a rotary motion to a linear motion or an advanced sealing technique such as needed in the rotation-type fluid compressing device is not required, so it has advantages such as simplification of the structure of the whole equipment and a smooth fluid compressing motion.
In addition, different from the compressor equipments of other types as described above, it is extremely easy to vary the piston stroke in the electromagnetic reciprocating pump. That is, the piston stroke of the electromagnetic reciprocating pump directly connected to the electromagnetic drive means can be varied with a relation of 1:1 by controlling the amplitude and/or frequency of the AC current to be supplied to the excitation winding of the electromagnetic drive means to vary its motion stroke. This is another advantage of the electromagnetic reciprocating pump.
Electromagnetic drive means suitable for the electromagnetic reciprocating pump is described in Maurice Barthalon's U.S. Pat. No. 3,542,495, for instance.
As described above, the electromagnetic reciprocating pump has many advantages as compared with other type compressor equipments, but no proposal was made in the past to the pressure control of its discharge fluid.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a pressure control system for an electromagnetic reciprocating pump which maintains the outlet pressure at a present value.
The characteristic feature of the present invention resides in that a pressure sensor for detecting the actual outlet pressure of the electromagnetic reciprocating pump, and the frequency of the reciprocating motion and, if necessary, its stroke of the electromagnetic drive means are feedback controlled by using the deviation from the preset outlet pressure of the actual outlet pressure detected by the pressure sensor. According to the control of the reciprocating motion frequency and/or stroke of the electromagnetic drive means, the number of times of the reciprocating motion and/or the stroke of the compressor piston connected to the electromagnetic drive means vary, whereby the outlet pressure of the electromagnetic reciprocating pump is controlled.
Also, the characteristic feature resides in that the reciprocating motion frequency control of the electromagnetic drive means is done by modulating the frequency and amplitude of the half-wave AC current supplied to the electromagnetic drive means. With this, the control of the number of times of the reciprocating motion of the electromagnetic drive means can be carried out without changing the reciprocating motion stroke of the electromagnetic drive means and with a relatively simple construction.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a block diagram of an embodiment of the present invention;
FIG. 2 is a longitudinal section showing the schematic structure of the compressor shown in FIG. 1;
FIG. 3 is a graph showing the relationship between the error signal which is output from the adder and the oscillation frequency of the frequency oscillator; and
FIG. 4 is a graph showing the realtionship between the error signal which is output from the adder and the DC voltage which is output from the variable voltage rectifier.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention is described in detail with reference to FIG. 1, which shows a block diagram of an embodiment of the present invention.
In the same figure, a pressure demand generator 1 specifies the pressure of the fluid to be discharged from an electromagnetic reciprocating pump 31. An adder 22 adds a pressure command signal Ps output from the pressure command generator 1 and a fluid pressure signal Pi output from a pressure sensor 11, which is to be described later on, thereby operating the error signal (deviation) E. A frequency oscillator 23 receives the error signal E output from the adder 22 and generates a signal of frequency F which is a function of the error signal E. A pulse signal generator 24 generates a pulse signal in response to the output frequency signal F of the frequency oscillator 23.
The pulse signal from the pulse signal generator 24 is input to a variable voltage rectifier 21, and a DC voltage Vr in a proportional relationship with the pulse signal or frequency signal is generated from the variable voltage rectifier 21.
A power converter 25 consists of two sets of DC-AC converters 25A and 25B which are comprised of thyristors and power transistors, etc., and each of them is supplied with the DC voltage Vr from the variable voltage rectifier 21. Also, the pulse signal is input to the gate of each DC-AC converter 25A, 25B (not shown) from the pulse signal generator 24, whereby the DC-AC converters 25A and 25B are controlled for firing. Whereupon, AC half-wave voltages of an amplitude depending on the output Vr of the variable voltage rectifier 21 and of a frequency depending on the output F of the frequency oscillator 23 are output alternately from the DC-AC converters 25A and 25B.
These half-wave AC voltages are supplied to the excitation windings 26L and 27L which are wound around the stator cores 26S and 27S of a first electromagnetic drive means 26 and a second electromagnetic drive means 27, respectively. In these excitation windings, excitation currents Ima and Imb flow alternately depending on the frequency and amplitude of the output voltage of the power converter 25. This allows magnetic fluxes Φa and Φb to be alternately induced in the stator cores 26S and 27S of the first and the second electromagnetic drive means 26 and 27, depending on the magnitude of the excitation currents Ima and Imb, respectively, attracting moving cores 26M and 27M. The first and second electromagnetic drive means 26 and 27 may be the same as described in the specification of the above-mentioned U.S. Pat., for instance. Of course, it is possible to omit one of the DC-AC converters 25A and 25B, supply one half-wave of the AC output of one DC-AC converter to the first electromagnetic drive means, and supply the other half-wave of the reverse phase to the second electromagnetic drive means.
To the moving cores 26M and 27M of the first and the second electromagnetic drive means 26 and 27, the piston 28B of a compressor 28 is attached via piston rods 26A and 27A, respectively. Since the moving cores 26M and 27M are alternately attracted in the directions reverse to each other, the piston 28B reciprocates.
FIG. 2 is a longitudinal section showing the profile of the compressor 28 where the same symbols as FIG. 1 represent the same or identical portions.
In FIG. 2, the piston 28B is slidably disposed in a compressor body 28C. Connected to the piston 28B are the piston rods 26A and 27A, which are connected to the movable portions of the first and the second electromagnetic drive means 26 and 27 (FIG. 1).
The compressor body 28C is divided by the piston 28B into two fluid chambers 100A and 100B, which are provided with an outlet valve 101A and an inlet valve 101B as well as an outlet valve 102A and an inlet valve 102B, respectively. For instance, when the piston 28B is driven in the direction of an arrow G by the motion of the first electromagnetic drive means 26, the fluid in the fluid chamber 100A is discharged into a fluid passage 28A through the outlet valve 101A, and a supplemental fluid is introduced into the fluid chamber 100B through the inlet valve 102B. When the piston 28B is moved in the direction reverse to that of the arrow G by the motion of the second electromagnetic drive means 27, the fluid introduced into the fluid chamber 100B is discharged into the fluid passage 28A through the outlet valve 102A, and another supplemental fluid is introduced into the fluid chamber 100A through the inlet valve 101B. The fluid discharged into the fluid passage 28A is introduced into a pressure tank 29.
The alternate traveling of the moving cores of the first and second electromagnetic drive means 26 and 27, as described above, causes the pistons 28B of the compressor 28 to reciprocate within the compressor body 28C.
As previously stated, when the first DC-AC converter 25A is driven by the firing pulse output from the pulse signal generator 24, the excitation current Ima flows in the first electromagnetic drive means 26, and the movable portion of the first electromagnetic drive means 26 causes the piston 28B of the compressor 28 to travel toward the first electromagnetic drive means 26 (in the direction of the arrow G in FIG. 2). The piston 28B stops at a point where the repulsive force of a return spring 32 of the movable portion of the first electromagnetic drive means 26 balances with the sum of the electromagnetic force Fma of the first electromagnetic drive means 26 and the restoring force of a return spring 33 of the movable portion of the second electromagnetic drive means 27, whereby the fluid is discharged from the fluid chamber 100A of the compressor 28 and the supplemental fluid is sucked into the fluid chamber 100B.
When the second DC-AC converter 25B is driven by the subsequent firing pulse, the operation of the first DC-AC converter 25A stops, the excitation current Ima of the first electromagnetic drive means 26 becomes 0, and simultaneously the excitation current Imb begins to flow in the excitation winding 27L of the second electromagnetic drive means 27. Whereupon, the movable portion of the second electromagnetic drive means 27 causes the piston 28B of the compressor 28 to travel toward the second electromagnetic drive means 27 (in the direction reverse to the arrow G in FIG. 2). The piston 28B stops at a point where the repulsive force of the return spring 33 balances with the sum of the electromagnetic force mb of the second electromagnetic drive means 27 and the restoring force of the return spring 32, whereby the fluid is discharged from the fluid chamber 100B of the compressor 28 and the supplemental fluid is sucked into the fluid chamber 100A.
By repetition of the above described operation, the fluid is fed under pressure to the pressure tank 29 via the fluid passage 28A. The fluid under a predetermined pressure which is stored in the pressure tank 29 is taken out to the exterior through a discharge quantity regulator means 30.
The pressure sensor 11 is provided in the pressure tank 29. The pressure sensor 11 detects the fluid pressure in the pressure tank 29 and outputs an electric signal (fluid pressure signal Pi) proportional to the pressure of the fluid. The fluid pressure signal Pi is sent to the adder 22, where it is added to the pressure command signal Ps issued by the pressure demand generator 1 and the sum signal is output as the error (deviation) signal E. In this embodiment, it is predetermined that the pressure command signal Ps assumes a positive value and the fluid pressure signal Pi a negative value.
FIG. 3 is a graph showing the relationship between the error signal E output from the adder 22 and the oscillation frequency F of the frequency oscillator 23. In the same figure, assuming that the maximum error signal which the electrogmagnetic reciprocating pump 31 may produce is Emax (Emax>0), and the oscillation frequencies when the error signal is Emax or 0 is Fmax or Fmin (Fmax>Fmin>0), then the oscillation frequency F is expressed by the following equation (1) when the error signal is E.
F=Fmin+E{(Fmax-Fmin)/Emax} (1)
FIG. 4 is a graph showing the relationship between the error signal E output from the added 22 and the DC voltage Vr output from the variable voltage rectifier 21. In the same figrue, if the DC voltages when the error signal is Emax or 0 is assumed to be Vrmax or Vrmin (Vrmax>Vrmin>0), the DC voltage Vr is expressed by the following equation (2) when the error signal is E.
Vr=Vrmin+E(Vrmax-Vrmin)/Emax (2)
At least one of the Fmin and Vrmin is set at the upper limit value of the dead band where the first and second electromagnetic drive means 26 and 27 do not operate. And the one of the Fmin and Vrmin which is not set at the upper limit value is set to a value beyond the dead band.
Therefore, if the error signal E is larger than 0, that is, if the actual outlet pressure is lower than the determined outlet pressure, the frequency and amplitude of the AC voltage supplied to the first and the second electromagnetic drive means 26 and 27 vary depending on the error signal E, whereby the number of reciprocating motions of the piston 28B of the compressor 28 varies and the quantity of the fluid fed under pressure from the compressor 28 to the pressure tank 29 changes. This is, the quantity of the fluid fed under pressure from the compressor 28 to the pressure tank 29 is feedback controlled according to the fluid pressure signal Pi output from the pressure sensor 11, and as a result, the actual outlet pressure of the electromagnetic reciprocating pump 31 is automatically controlled so as to match the preset outlet pressure.
If the error signal is zero or a negative value, at least one of the oscillation frequency F and the output voltage Vr would not be larger than the upper limit value Fmin or Vrmin of the bed dead bands, so that the first and the second electromagnetic drive means 26 and 27 would not be operated.
For instance, if the frequency of the AC voltage is increased, inductance of the excitation windings of the first and the second electromagnetic drive means 26 and 27 also increase and the excitation currents decrease, so that the reciplocating strokes of the movable portions of the first and the second electromagnetic drive means 26 and 27 tend to become smaller. Since the amplitude of the output voltage of the DC-AC converter 25 is also varied along with change in the frequency of the output voltage in this embodiment, however, the currents flowing in the excitation windings can be kept constant even if inductance of the excitation windings varies. As a result, the reciprocation stroke of the movable cores of the first and the second electromagentic drive means 26 and 27, namely of the piston 28B, can always be maintained constant. In addition, the voltage control can also be made so that the excitation winding currents also increase as the frequency increases and conversely, so that the excitation currents also decrease as the frequency decreases. This enables the same effect to be obtained as that obtained when the gain of the control loop is made larger.
As shown in FIG. 1 by dotted lines, the control of the DC voltage Vr by the error signal E may be omitted. In this case, by only control of the frequency of the AC voltages supplied to the first and the second electromagnetic drive means 26 and 27, the actual outlet pressure of the electromagnetic reciprocating pump 31 can be made to match the preset outlet pressure.
If the travel distance of the movable portions of the first and the second electromagentic drive means 26 and 27 is assumed to be x, the travel distance or the stroke of the piston 28B of the compressor 28 is also x, so, if the sectional area of the piston 28B is S, the entrapment volume U of the fluid is S.x. In this embodiment, as shown in FIG. 2, when the piston 28B moves in the direction of the arrow G, the fluid is discharged from the fluid chamber 100A, and when it moves in the reverse direction, the fluid discharge is performed from the fluid chamber 100B, so that the fluid two times of the entrapment volume U can be compressively discharged during one cycle.
It is natural that the present invention can be applied not only to an electromagnetic reciprocating pump having a compressor driven by two electromagnetic drive means as shown in FIGS. 1 and 2, but also can be applied to an electromagnetic reciprocating pump having a compressor driven by single electromagnetic drive means.
Further, althrough it has been described that the oscilation frequency F and the variable output voltage Vr vary according to the error signal E as shown in FIGS. 3 and 4, the frequency F and the voltage Vr may be set at fixed values exceeding the dead band only if E is positive, and they may be set within the dead band if E is 0 or negative.
As apparent from the above description, the following technical advantages are accomplished by the present invention.
(1) By feedback controlling the reciprocating motion frequency of the electromagnetic drive means on the basis of the error signal which is a function of the actual outlet pressure and preset outlet pressure of an electromagnetic reciprocating pump so that the error signal nears 0, thereby to regulate the number of times of the reciprocation of the compressor connected to the electromagnetic drive means, the actual outlet pressure of the electromagnetic reciprocating pump is always maintained at the preset outlet pressure.
(2) By performing the oscillation frequency control of the electromagnetic drive means through modulation of the frequency and amplitude of the half-wave AC current supplied to the electromagnetic drive means, the oscillation frequency control of the electromagnetic drive means can be performed accurately with a relatively simple arrangement without effecting the reciprocation stroke of the drive means.
(3) By only control of the frequency of the AC voltages supplied to the first and the second electromagnetic drive means, the actual outlet pressure of the electromagnetic reciproccating pump 31 can be made to match the preset outlet pressure. | An electromagnetic reciprocating pump which maintains the outlet pressure at a preset value comprising a pressure sensor for detecting the actual outlet pressure of the electromagnetic reciprocating pump and means to feedback control the frequency of the reciprocating motion and, if necessary, its stroke of the electromagnetic drive means based on the deviation from the preset outlet pressure of the actual outlet pressure. The reciprocating motion frequency control of the electromagnetic drive means may be done by modulating the frequency and amplitude of the half-wave AC current supplied to the electromagnetic drive means. With this, the control of the number of times of the reciprocating motion of the electromagnetic drive means can be carried out without changing the reciprocating motion stroke of the electromagnetic drive means. | 5 |
FIELD AND BACKGROUND OF THE INVENTION
This invention relates in general to the construction of venetian blinds and in particular to a new and useful method and apparatus for assembling individual slats into an armor shutter.
There are known methods of this kind in which the slats are fed from a magazine of an inserting device where the connecting elements provided with a catch for the loops of carrier strips are to be secured to the beaded edges of the slats. Upon a usually manual removal of the slats which are provided with connecting elements, the slats are assembled to shutters in a separate apparatus, by suspending the loops of the carrier strips from the corresponding portions of the connecting elements. This method of manufacturing is complicated and time consuming and requires much space, particularly if the slatted armor shutter is to be broad, such as several meters.
SUMMARY OF THE INVENTION
The present invention is directed to a method and device, permitting the manufacture of a shutter starting from finished slats, in a single continuous operation and in one and the same apparatus, which makes it possible to provide suitable control means, save space, and avoid any manual intervention and change of equipment.
In accordance with the method of the invention, a slatted armor shutter is manufactured by arranging the slats which have beads at end in a vertical stack, removing individual slats from the vertical stack into a support position where they are held firmly, introducing connecting elements from each side of the beaded edges of the slats as they are held individually, interengage one connecting element with the other, moving the slats by steps downwardly corresponding to the spacing of the carrier strip loops which is desired until the last slat to be assembled reaches a cutting station, cutting the carrier band through at a distance above the slat and letting the slat drop into a new stack of a desired number with the assembled band.
With the invention, a slat is connected to a connecting element which includes a rear hook portion which is bendable into a securing loop and a front slat penetrating brad portion which is driven into the bead of the slat. A blind slat band is engaged through the openings of a holder part of a carrier strip which has a loop portion which is engageable in the hook portion of the connecting element. Advantageously the connecting element is applied first and mounted so that its hook portion will engage the loop portion of the carrier strip as it is moved downwardly and means are then provided for closing the hook portion into a loop so that the two parts become interengaged.
The individual tools and conveying means provided at the various stations within a vertically extended enclosure may be actuated hydraulically, for example, and a program control may be provided for this operation. It is advisable to associate the various working stations with monitoring elements which are connected to the control, and to interrupt the manufacturing process if erroneous operations appear.
Accordingly, it is an object of the invention to provide an improved assembly apparatus for assembling individual slats into an armor shutter.
A further object of the invention is to provide an apparatus for assembling the carrier strip connecting element to a beaded portion of each slat in a carrier strip to the connecting element.
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 specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which a preferred embodiment of the invention is illustrated.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 is a schematic front view of the apparatus comprising various working units;
FIGS. 2 and 3 show the receiving station of the apparatus;
FIGS. 4 and 5 are enlarged side and top plan views respectively illustrating the driving of the connecting elements into the beaded edge of a slat;
FIG. 6 shows the operation of a fastening station of the apparatus;
FIGS. 7 and 8 are enlarged top plan views showing the engaging of the loops and closing of the hooks in the fastening station;
FIGS. 7 and 8, are enlarged top plan views showing the engaging of the loops and closing of the hooks in the fastening station;
FIG. 9 illustrates the operation of both the receiving and the fastening stations, terminating with the closing of the hooks;
FIG. 10 illustrates the further displacement of the slats, after the hooks have been closed, and stacking of the finished armor shutter ready for removal and;
FIG. 11 is a schematic view similar to FIG. 1 showing part of the complete apparatus.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawings in particular the invention embodied therein comprises an apparatus and method for manufacturing a slatted armor shutter in which individual slats 2 having a bead portion 2a at each end are assembled to a slat carrier strip connecting element 5 which includes a rear hook portion 5a which is bendable into a securing loop and a front slat penetrating brad portion which is engageable into the slat bead portion 2a as shown in FIG. 5.
The drawing shows a magazine 1 accommodating a stack of horizontally superposed slats 2 having beaded edges (which protrude inwardly in the stack). The lowermost slat 2 in this stack reposes on rollers 3 which are transversely extensible and retractable by means of a fluid pressure operated piston device 3a. Below rollers 3, parting elements 4 are provided which also are extensible and retractable by means of piston devices 4a.
Laterally, yet within the enclosure of the apparatus, extending downwardly of the magazine 1, clamps 6 are provided into which connecting elements 5 can be introduced by means of a feeder (not shown) and which are actuable by means of a piston device 6a. The clamps can be moved back and forth by means of another piston device 6b, to drive connecting elements 5 into the beaded edge of the slat. This receiving station is associated with a supporting mechanism 8 which is movable by means of a piston device 8a transversely to or above the central space of the enclosure, and which comprises a section gripper 7 vertically displaceable by means of another piston device 7a.
Below supporting mechanism 8 are conveyance means for feeding in carrier strips 9 which are provided with loops 9a and are run in the enclosure downwardly on each side past a central fastening station. At this fastening station, suspension clamps 11 are provided which are actuable by piston devices 11a and associated each with a pusher 10 which is intended for bending the hook portions 5a of the connecting elements 5. The pusher 10 is actuable by means of still another piston device 10a. Below this fastening station, strip advancing clamps 12 are provided which are actuable by piston device 12a and vertically displaceable by another piston device 12b.
Clamping heads 13 are provided below strip advancing clamps 12, which are actuable by piston devices 13a and are supplied with connecting clamps. Below clamping heads 13, strip cutters 14 are provided which are actuable by piston devices 14a and extensible and retractable through another piston device 14b. In the downwardly adjacent space of the enclosure, a gripping device 15 equipped with a suction gripper for the slats is provided which can be moved by a piston device 15a transversely into and out of a standby position in the enclosure and is actuable by means of another piston device 15b. At the lower end of the enclosure, a conveying device 17 is provided for receiving and further displacing the finished armor shutter 16.
The various piston devices, for which also other actuating devices may be substituted, may be operated hydraulically or pneumatically. It is advisable to connect a further control, so that they perform their operation in a predetermined programmed cycle, optically monitoring elements may be associated with each operating step which follow the individual steps and interrupt the cycle if an error is detected.
With the just described apparatus, the inventive method may be carried out as follows:
As soon as, with rollers 3 extended into their working position, slats 2 are introduced into magazine 1, parting elements 4 are extended, the rollers 3 are retracted so that the stack drops to parting elements 4. Support 8 is then moved into its working position and suction gripper 7 is moved up close below the lowermost slat 2 of the stack. Upon a following retraction of parting elements 4, the stack drops on suction gripper 7 (FIG. 2). Now, parting elements 4 are extended again, so that they engage between the lowermost and the superjacent slat 2 of the stack, thus separating the two slats. Suction gripper 7 is then retracted, so that the lowermost slat supported thereon comes into the receiving station of support 8.
As better shown in FIGS. 4 and 5, in this station, the clamps 6 each carrying a connecting element 5 and slightly inclined downwardly to be directed against the respective beaded edge 2a of a slat 2, are pushed forward so that connecting elements 5, each provided with a point, are driven through the outer wall of the associated bead 2a and firmly fixed therein. The open hook 5a of the connecting element 5, which reamins projecting from the beaded edge, then extends in a plane approximately parallel to that of the slat.
After the empty clamps 6 retract, (to receive a new connecting element 5), the gripping device 15 is moved to the center of the enclosure and the suction gripper thereof is extended upwardly until it applies against the slat 2 held by support 8 (FIG. 3). This lifts slat 2 clear of the receiving station in support 8 so that support 8 can be moved back to its position as shown in FIG. 1 or 6.
It will be understood that support 8 and gripping device 15 are spaced from each other in the longitudinal direction of the slat. Suction gripper 7 of support 8 is disengaged from the slat and moved back into its initial position laterally of the enclosure center along with support 8. The suction gripper of gripping device 15, now holding the slat, is then retracted downwardly (FIG. 6) until the slat 2 provided with connecting elements 5 comes into the zone of suspension clamps 11 (FIG. 7). Upon extending suspension clamps 11, and engaging loops 9a of carrier strip 9 to open hooks 5a (by correspondingly moving the clamp in the plane of the slat), the pushers 10 (FIGS. 8 and 9) are actuated, whereby hooks 5a are bent to close and trop loops 9a. The slat is now suspended from carrier strips 9 and the gripper of gripper device 15 can be lowered and moved into its initial position off the center of the enclosure (FIG. 9). Simultaneously, with the bending of hooks 5a and the retraction of gripping device 15, the next slat 2 is separated in the described manner in magazine 1 from the stack and moved into the receiving station, where the same cycle is repeated. As to the first slat 2, now suspended from strips 9, the advance clamps 12 now become effective (FIG. 10) and convey this slat along with the carrier strips 9, downwardly through a step corresponding to the spacing of the carrier strips loop portions 9a on the strips 9. In this new position, advance clamps 12 oepn and are moved back into their initial position by piston device 12b.
In the just described manner, all the slats to be assembled to an armor shutter are moved from the magazine and conveyed downwardly. The lowermost slat thus reaches the conveying device 17 where, as soon as the last slat of the assembled shutter have arrived, a stack 16 is formed. As this happens, i.e. when the last slat is moved by advance clamps 12 from the hook bending position through a step downwardly and the advance clamp 12 is returned into its initial position, clamps 12 are moved again to engage strips 9. Now, by means of clamping head 13, the usual connecting clamp (now shown) is fitted onto the carrier strip 9. Then, cutters 14 are actuated and the strips are cut through between the uppermost slat of the assembled shutter and the connecting clamps (FIG. 11). This causes all of those slats which are still at more elevated locations within the central space 22 of the enclosure and which are suspended from the stips, to drop onto the stack 16 which is then removed by conveying device 17 which moves the stack 16 in a direction out of the plane of FIG. 11. Since above the cut location of cutters 14, the working cycle continues in the described manner, a new stack of slats and strips starts to form on the conveying device. FIG. 11 schematically shows how the gripping device 15 is positioned in a manner that is clear of the slats 2 and the stack 16.
This makes possible the fully automatic assemblage. The apparatus does not require much space, since the height of the needed enclosure is small. None of the needed operations is manual, and since the operations follow each other, continuously, no transfer to different locations is necessary.
In the above example, the connecting elements are provided with hooks into which, after the connecting elements 5 are driven into the beaded edge 22, the loops of the carrier strips 9 are engaged. It is possible of course, first to engage, for example, U-shaped connecting elements into the loops, and only then drive the two legs of the U into the beads. This can be done in the same working station. Other connecting elements may have hooks formed thereon in such a way that upon engaging the loops of the strip on the hook already driven into the bead, no bending of the hook is necessary.
While a specific embodiment of the invention has been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles. | The method starts with bringing the stack of slats to be assembled into a standby position. The slats are then removed from the bottom of the magazine and stepwise provided with connecting elements having hooks which are then engaged with loops provided on carrier strips of the shutter. Thereupon, the hooks are bent to close and the slats are moved downwardly by steps. After suspending the last slat, the carrier strips are cut through above the last slat, so that on a conveyor provided below, the assembled shutter forms a stack to be removed. This process is continuous, so that in immediate succession, the assemblage of a further shutter begins. | 4 |
This is a division of 08/449,747 filed May 25, 1995 now U.S. Pat. No. 5,655,703.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention, generally, relates to a process for making organic chip packages and, more particularly, to a new and improved technique by which chips are attached to substrates and substrates are attached to circuit boards that permit the substrates to be removed without affecting other attachments.
In recent years, much effort has been devoted to problems that are involved in soldering laminate chip carriers to circuit boards, and happily, many rather sophisticated problems have been solved by recognizing some of the characteristics and requirements for making the soldering connections between the chip carriers and the circuit boards. Then, before the rejoicing died down, it appeared that all of these efforts were for naught when it was found that in soldering a chip module to a mother board, the solder connections between the chip and the chip carrier in the chip module were damaged severely or destroyed completely.
It has become increasingly evident that chip modules must be removed or de-soldered from a mother board for replacement with a new or updated module or when it becomes necessary to perform other repair work. During these activities, the soldering connections between the chip and the chip carrier of the new module, or other neighboring modules on the mother board, are damaged due to thermal exposure.
An example of the type of soldering connection that is damaged by such repairs or rework is U.S. Pat. No. 4,480,261 to Hattori et al., which explains the problem and describes the complexity involved in developing a solution. This patent is of absolutely no relevance to the present invention, however.
Currently, chips are provided during manufacture with balls of solder at points where they are to be attached to a carrier, module or substrate. These balls are a Pb--Sn solder used by some manufacturers in a technique known as Controlled Collapse Chip Connection (called "C-4").
It is connections involving the C-4 balls that are damaged during heating when a module is removed or otherwise involved in a process requiring a temperature above 183 degrees C. When these connections are subjected to these temperatures, there is flow of molten Sn--Pb eutectic solder into the interface that exists between the chip and the encapsulant material.
In addition to the above identified solder flow during rework temperatures, residual moisture within the chip-carrier assembly will be converted to vapor causing large scale flow of the solder into the chip/encapsulant interface. When this occurs, severe shorting results.
2. Description of the Prior Art
The Assignee of the present invention has devoted substantial research seeking a way to avoid these activities that result in damage to soldering connections between substrates and circuit boards, such
U.S. Pat. No. 4,914,814 to Behun et al. describes a process using miniature pins with solder to form a bonding connection.
U.S. Pat. No. 5,060,844 to Behun et al. which describes a use of two solders and an epoxy layer about one of them.
IBM Technical Disclosure Bulletin, Vol. 14, No. 8, January 1972, by Martyak et al. describes the use of two solders in a distinctive structural arrangement to maintain separation.
While the methods and circuit arrangements of the prior art at first appearances have similarities with the present invention, they differ in material respects. These differences, as will be described in more detail hereinafter, are essential for the effective use of the invention and which admit of the advantages that are not available with the prior art.
OBJECTS AND SUMMARY OF THE INVENTION
It is an important object of the invention to provide a technique of attachment between a chip, a chip carrier and a circuit board whereby the module may be soldered to and/or de-soldered from the circuit board without disturbing the solder between the chip and the chip carrier.
Another object of the present invention is to provide a solder technique which permits a chip carrier to be exposed to higher temperature limits without damage to its solder connections.
Still another object of the invention is to provide a technique for connecting chips to carriers, modules or substrates that eliminates re-melting of solder connections within the carriers, modules or substrates during later solder work.
Briefly, the technique of the present invention involves attaching a chip to a carrier, and then the carrier to a mother board, by selecting a three level hierarchy of solders by temperature, level one being the highest temperature and level three being the lowest. Solder of level one in the hierarchy is used to form C-4 solder balls on the chip, and solder of level three is used to attach the carrier to a circuit board. Solder of level two in the hierarchy of solders is used to connect the C-4 solder balls to the carrier.
The above and other objects, advantages and features of the present invention will become apparent from the following detailed description of the presently preferred embodiment as illustrated in the accompanying single drawing FIGURE.
BRIEF DESCRIPTION OF THE DRAWINGS
The single drawing FIGURE is a cross sectional view in elevation illustrating a chip attached to a carrier which, in turn, is attached to a circuit board in accordance with the invention.
DETAILED DESCRIPTION OF THE INVENTION
The single drawing FIGURE illustrates a hierarchical selection of solders by their melting temperatures in an arrangement to solve a problem that arises during a process that involves soldering a chip carrier or module to a mother board.
When an assembly, such as that shown in the drawing, is subjected to a temperature above 183 degrees C., problems arise due to several factors, all of which are undesirable. These will be described in more detail as the description of the invention proceeds.
In the drawing, an assembly constructed and arranged according to the principles of the invention is identified, generally, by the numeral 10. A chip 11 has solder balls 12 formed at locations where the chip is to be attached to a carrier 13.
The solder balls 12 are called C-4 solder material, and these usually are pre-formed on chips during manufacture. C-4 solder is a high temperature material which, until about 1990, was formed of 95% Pb-5% Sn, but today it consists of 97% Pb-3% Sn.
When the carrier 13 is soldered to or de-soldered from its circuit board, it is subjected to a temperature of about 183 degrees C. Unless the technique of the present invention is followed, the exposure to this temperature will cause solder 14 to melt, producing the undesirable effects described infra.
For the purposes of the present invention, the C-4 solder can be formed of any high Pb material, for example, in the range of 90% to 97% Pb, with a small percentage of Sn material, for example, in the range of 3% to 10%. These materials melt at a high temperature, such as 300 degree C.
However, when attaching chips to organic carriers to make an organic module, a temperature of 300 degrees C. is too high for organics. Therefore, a solder with a lower melting point, such as a solder in the range 2.0% to 3.5% Ag-98% to 96.5% Sn with a melting temperature in the range of 221 to 229 degrees C., is applied to the organic carrier first. This solder is identified generally in the drawing by the reference number 14.
Now, a chip with the C-4 solder balls 12 is placed, along with an appropriate flux, against the lower temperature solder 14 on the organic carrier, and the temperature is raised to about 240 degrees C. The C-4 solder balls 12 are only wetted by the solder 14, and the solder balls become attached.
Frequently, these modules thus formed are sealed with a suitable encapsulant material 15, but the hierarchical method of the invention is applicable whether the module is encapsulated or not. Normally, such a module will have points on the opposite side, the lower side as viewed in the drawing, for attaching to a circuit board, called "mother" board.
To attach the chip-carrier module to a circuit board 16, a third solder is used having a melting temperature of 179 to 183 degrees C. The third solder is identified generally in the drawing by the reference number 17.
The third solder 17, in accordance with the invention, can be an Ag-modified eutectic solder, such as 62% Sn-36% Pb-2% Ag, which melts at 179 degrees C., or it can be the unmodified eutectic 63% Sn-37% Pb solder which melts at 183 degrees C. The three solders in the hierarchy of solders of the present invention are limited primarily by the temperature at which each melts, rather than a particular material composition of the solder.
In the past, it has been most difficult to attach a chip carrier to a circuit board because severe melting of solder 14 occurred. With the hierarchy of solders of the present invention, some insignificant softening of the solder 14 may occur, but there will be no wholescale melting with the resulting flow of solder into crevices in the encapsulant material causing electrical short circuits and the other problems experienced in the past.
A principal purpose of these solder attachment points is two fold: (1) to form a secure mechanical connection holding the parts physically together as one unit; and (2) to form a good electrical connection between any two points joined. Therefore, it is the intent of the hierarchy of solders to identify the solders by a temperature or a temperature range, rather than by a solder material.
The hierarchy of solders of the invention is most significant when used in the manufacture of organic chip packages, because such packages involve at least one chip attached to an organic substrate by the C-4 method of forming solder joints. Then, the module so formed is encapsulated to form a package.
It is this package formed as just described above that must be attached to a circuit board using solder. In other words, it is such an organic chip package that is subjected to soldering twice. The hierarchy of solders of the invention is less significant when a chip is attached directly to a circuit board where such a circuit board is the final product.
Organic chip modules with which the invention is most applicable are being used increasingly in the manufacture of packages in today's electronic industry. These organic chip modules may have a single chip or a plurality of chips on the top surface of the substrate, the bottom surface of which may have, in place of the usual solder balls, solder lands or solder bumps.
The solder balls, lands or bumps are used for attaching the modules to a circuit board, sometimes called a "mother" board in the electronics industry. It is usual also in this industry that electrical circuits are formed on the top surface of the organic carrier, substrate or laminate.
To summarize the hierarchy of solders technique of the invention, the C-4 solder balls (solder 1 in the drawing) is a high temperature solder that melts at over 300 degrees C. These solder balls do not melt when the chip is attached to the top surface of a laminate.
The attachment technique of the invention is accomplished by depositing another solder (solder 2 in the drawing) on the top surface of a laminate where the chip is to be connected. Such a solder has a melting temperature of about 220 degrees C., and when attaching the chip, the solder is subjected to a temperature of about 220 degrees C., which is just sufficient to melt it while the solder balls are only softened or wetted.
Following the attachment of the chip to the laminate, if it is to be encapsulated, it is done at this point in the manufacturing process.
When the module formed as described above is to be attached to a circuit board, a eutectic solder (solder 3 in the drawing) is used, such as 63% Sn-37% Pb. Such a solder has a melting temperature in the order of 179 to 183 degrees C., which is about 40 degrees C. lower than solder 2.
It is most significant, for the hierarchy of solders of the invention, that while various solder materials may be used, the melting point of solder 2 is intermediate that of solders 1 and 3.
Although the invention has been described in detail, it is understood that changes and modifications can be made. Therefore, the invention is to be limited only by the following claims. | The method for soldering a chip to a substrate to form a module and then soldering the module to a circuit board includes selecting a three level hierarchy of solders by the temperature required to melt. By this method, a module can be soldered to and de-soldered from a circuit board without affecting adversely the solder between the chip and the substrate. The package formed by this method is free of faults that are caused frequently during both manufacture and service. | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to self-loading firearms. More particularly, the present invention relates to the operating system of indirect gas-operated firearms in the AR15/M16 series of firearms and specifically the bolt carrier for use in such firearms.
2. Description of the Related Art
The AR15/M16 family of weapons and their derivatives including indirect gas operated versions, have been in use by the military and civilian population for many years. An essential part of this firearm's design is the bolt carrier which typically includes a bolt mounted in the carrier for axial sliding movement and rotation, a firing pin slidably mounted within the bolt and bolt carrier for restricted reciprocating axial movement, and a cam pin for producing relative rotation between the bolt and the bolt carrier.
The bolt carrier is generally cylindrical in shape with a longitudinally extending circular bore throughout its length. An elongated opening is provided in the top and bottom of the carrier to allow the hammer to extend into the interior of the bolt carrier and strike the firing pin. The rear of the carrier is received within the firearm receiver and the front of the carrier houses the bolt. The upper surface of the carrier immediately adjacent the front face includes a flat shelf for engagement with a charging handle.
The top of the carrier in front of the opening is machined to receive a carrier key which operates in conjunction with the operating rod of the firearm's gas operating system to cycle the bolt action in automatic and semi-automatic operation. A carrier with a separate carrier key that is attached to the carrier with fasteners is set forth in U.S. Pat. No. 7,461,581 (“the '581 patent”), which is owned by the assignee of the present application and is hereby expressly incorporated by reference as if fully set forth herein. This two-part construction necessitates careful machining of both the carrier and the carrier key to ensure a close fit within a narrow tolerance.
In a conventional indirect gas operated firearm, the operating rod of the gas operating system contacts the strike face of the carrier key after the weapon is fired and gas pressure displaces the operating rod rearwardly. Because the strike face is above the central axis of the bolt carrier, an undesirable phenomenon known as carrier tilt occurs during the normal operation of the firearm. Carrier tilt can be defined as the rear of the carrier tilting downwardly when the strike face has been contacted by the operating rod, resulting in the rearward movement of the carrier being resisted when the now off-axis carrier strikes the forward leading edge of the receiver extension. Eliminating carrier tilt would be a very desirable attribute.
About the exterior of the bolt carrier are a series of longitudinally extending lands or rails, usually four, which make contact with the cylindrical interior surface of the upper receiver of the firearm and serve to align the bolt carrier within the receiver. The rails include two upper rails and two lower rails spaced from one another about the exterior circumference of the bolt carrier. The upper rails extend from the elongated opening to the rear edge of the charging handle engagement shelf. The two lower rails are generally parallel with the upper rails and extend from the elongated opening all the way to the front face of the carrier.
Conventionally, the rails are contiguous and held to tight tolerance with the running surfaces in the upper receiver. Firearms such as the Stoner type rifle are very prone to stoppages and malfunctions when sand or dirt works into the receiver. Therefore, a need exists for a rail configuration that supports the carrier while reducing the likelihood of firearm malfunction when exposed to dirt and sand.
The rear end of the carrier typically does not contact the inside of the receiver but rather is supported by the longitudinal rails. To further support the carrier against carrier tilt, the rear of the carrier may be provided with a generally cylindrical boss having an outer diameter larger than the main body of the bolt carrier as described in a copending application filed on Oct. 10, 2008, entitled “Automatic Rifle Bolt Carrier with Fluted Boss”, by Jesus S. Gomez and Jason Miller (hereinafter, “the Gomez application”), which is also owned by the assignee of the present application and is hereby expressly incorporated by reference as if fully set forth herein. The boss in the Gomez application has an outer diameter large enough to make contact with the cylindrical inside of the receiver extension to ensure that the carrier centers therein.
Firearms based on the ARI5/MI6 family are the primary weapon of choice for military units in the United States and abroad. Highly trained units from all branches of service often find themselves operating in aquatic conditions prior to coming on land. The inability of the ARI5/MI6 series of weapons to be fired when water is present in the operating system puts these military personnel in a compromising position. With the current ARI5/MI6 series of weapons, and their derivatives, the firearm must be drained of all water prior to being discharged. This draining is not convenient or practical for a soldier who may come under fire immediately upon landing on a beach. Such situations are typically referred to as “over the beach operations”. Incorporating features into the operating system which allow the firearm to be immediately discharged upon exit from an aquatic environment would be highly desirable. One such feature is set forth in the Gomez application, namely, a series of longitudinal cuts or flutes spaced about the circumference of the boss to allow for water to pass by the boss. Additional water removal features would also be desirable.
It would be highly advantageous, therefore, to remedy the foregoing and other deficiencies inherent in the prior art.
SUMMARY OF THE INVENTION
In view of the foregoing, one object of the present invention is to overcome the shortcomings in the design of bolt carriers and bolts for self-loading firearms as described above.
Another object of the present invention is to overcome the phenomenon of carrier tilt in gas-operated automatic and semi-automatic firearms.
Yet another object of the present invention is to provide a bolt carrier for a gas-operated automatic or semi-automatic firearm having an carrier key integrally formed with the carrier to facilitate carrier design and manufacture.
A further object of the present invention is to provide a bolt carrier for a gas-operated automatic or semi-automatic firearm in accordance with the preceding objects in which the integral carrier key has a spherical strike face and a cylindrical counterbore which acts against the off-axis force imparted by the operating rod of the firearm's gas operating system during operation of the firearm to prevent carrier tilt.
A still further object of the present invention is to provide a bolt carrier for a gas-operated automatic or semi-automatic firearm in accordance with the preceding objects in which the rear of the carrier includes an enlarged boss as described in the Gomez application that engages the receiver to further reduce carrier tilt.
Another object of the present invention is to provide a bolt carrier for a gas-operated automatic or semi-automatic firearm in accordance with the preceding objects in which the boss has a plurality of cuts or flutes formed therein as described in the Gomez application to allow for water transfer, making the firearm safe for use in over the beach operations.
Yet another object of the present invention is to provide a bolt carrier for a gas-operated automatic or semi-automatic firearm in accordance with the preceding objects in which the rails on the upper surface of the carrier are extended all the way to the front face of the carrier to further mitigate carrier tilt.
A further object of the present invention is to provide a bolt carrier for a gas-operated automatic or semi-automatic firearm in accordance with the preceding objects in which the rails of the carrier have relief or sand cuts that provide a place for dirt and sand to accumulate so that such debris will not jam the firearm.
Another object of the present invention is to provide a bolt carrier for a gas-operated automatic or semi-automatic firearm in accordance with the preceding objects in which drain holes are provided in the bottom and rear of the receiver extension to allow water in the receiver extension to escape.
Yet another object of the present invention is to provide an improved bolt carrier in accordance with the preceding objects that can be used to upgrade existing weapons in the field without the requirement for any tools.
A still further object of the present invention to provide an improved bolt carrier for a rotary bolt action gun that is not complex in structure and which can be manufactured at low cost but yet greatly increases the reliability and safety of the firearm.
In accordance with these and other objects, the present invention is directed to a firearm from the AR15/M16 family, or an indirect gas-operated derivative, having a bolt carrier as previously described, with an improved bolt carrier which can be retrofitted to existing firearms of the AR15/M16 family of firearms using an indirect gas-operated system without any modification to the receiver of the firearm or any other part thereof.
The bolt carrier has several features that reduce carrier tilt. First, the carrier includes an integrally formed carrier key having a downwardly angled spherical strike face with a cylindrical counterbore to act against the tilting force imparted by the operating rod of the gas operating system. Second, the rear of the carrier includes a boss having a larger diameter relative to the main body of the carrier to ensure that the carrier is centered in the receiver and receiver extension, further mitigating carrier tilt as discussed previously in connection with the Gomez application. Third, the upper rails on the outer circumference of the carrier are extended to the front face of the carrier to provide longer rail support surfaces and still further reduce tilting of the carrier during operation.
In addition to reducing carrier tilt, the bolt carrier according to the present invention also includes features that reduce manufacturing costs and improve the robust operation of the firearm in adverse conditions. In particular, the bolt carrier of the instant invention has a carrier key integrally formed with the bolt carrier as one piece. This one-piece construction reduces manufacturing complexity and cost.
Further, for over the beach operations, the sides of the boss at the rear of the carrier have cuts or flutes formed therein to allow water to pass as already discussed. According to the present invention, these flutes work in conjunction with drain holes that are provided in the bottom and rear of the receiver extension. Specifically, as the weapon is fired, the bolt carrier moves rearwardly into the receiver extension. Water present in the receiver extension is forced, by the pumping action created by the moving bolt carrier, outwardly through the drain holes in the receiver extension to empty the receiver extension of water. In addition, water can pass through the flutes in the boss to exit the receiver and receiver extension by moving past the carrier as a result of the same pumping action created by the cycling of the bolt carrier during firing.
In addition, for improved performance in sandy and dirty conditions, the rails on the forward end of the carrier that contact the receiver have relief or sand cuts formed therein to provide a recess for dirt and dust to accumulate during operation of the firearm so that debris will not jam the weapon.
Finally, to improve the durability of the weapon, the operating rod is preferably made of a super alloy with high nickel and cobalt content.
These together with other improvements and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a bolt carrier according to the present invention.
FIG. 2 is another perspective view of the bolt carrier shown in FIG. 1 .
FIG. 3A shows the bolt carrier of FIGS. 1 and 2 with the other components of a firearm in battery.
FIG. 3B is an exploded view of the firearm components shown in FIG. 3A .
FIG. 4 is an end view of the integrally formed carrier key and strike face of the bolt carrier of FIGS. 1-3 .
FIG. 4A is a cross-sectional view taken along line A-A of FIG. 4 .
FIG. 4B is an enlarged view of detail B of FIG. 4 .
FIG. 5 is a partial perspective view of the firearm of FIG. 3 showing the forces exerted on the firearm when the action is first initiated upon firing of the weapon.
FIG. 6 shows the firearm of FIG. 5 after the operating rod, under gas pressure produced by firing, has struck the carrier key and initiated rearward movement of the bolt carrier.
FIG. 7 is an upper perspective view of the bolt carrier of FIGS. 1 and 2 as received within the receiver.
FIG. 8 is a lower perspective view of the components shown in FIG. 7 .
FIG. 9A is a perspective view of the receiver extension of the firearm shown in FIG. 3 .
FIG. 9B is a perspective bottom view of the receiver extension shown in FIG. 9A , showing the drain holes therein.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
In describing a preferred embodiment of the invention illustrated in the drawings, specific terminology will be resorted to for the sake of clarity. However, the invention is not intended to be limited to the specific terms so selected, and it is to be understood that each specific term includes all technical equivalents which operate in a similar manner to accomplish a similar purpose.
As used herein, the word “front” or “forward” corresponds to the end of the bolt carrier where the strike face is located, i.e., to the right as shown in FIGS. 1 and 2 . The “rear” or “rearward” or “back” corresponds to the direction opposite the end of the bolt carrier where the strike face is located, i.e., to the left as shown in FIGS. 1 and 2 . The term “battery” refers to the position of readiness of a firearm for firing.
As shown in FIGS. 1 and 2 , the present invention is directed to a bolt carrier generally designated by reference numeral 10 . It will be understood that bolt carrier 10 is intended to be employed with any indirect gas-operated firearm. It will also be understood that bolt carrier 10 is carried by an upper receiver 12 that cooperates with a lower receiver 11 and receiver extension 41 of a gas-operated automatic or semi-automatic firearm, generally designated by reference numeral 13 , as shown in FIGS. 3A and 3B . As is known, the firearm 13 includes a gas operating system generally designated by reference numeral 42 , and a barrel 43 . The receiver extension is received within the buttstock 49 .
In FIGS. 1 and 2 , the preferred embodiment of the bolt carrier 10 is shown. The bolt carrier 10 includes a hammer clearance slot 14 which permits the hammer (not shown but well known in the art) to extend into the bolt carrier 10 and strike a firing pin (not shown) positioned in bore 16 .
The exterior of the carrier includes a door opener 18 which provides room for the door latch (well known in the art) to close, and a cam slot 20 which provides a contained area for the cam pin (not shown) to rotate thus allowing the bolt 22 (see FIG. 6 ) to move rearwardly and rotate axially in the bolt carrier 10 ; the cam pin retains the bolt 22 within the bolt carrier 10 as is known in the art. One side of the bolt carrier 10 is provided with forward assist notches 24 as is well known in the art. The top of the carrier immediately adjacent the front face 26 thereof has a flat charging handle engagement shelf 28 for a charging handle 82 (see FIGS. 7 and 8 ), as is also known in the art.
The top of the bolt carrier is formed with an integral carrier key 30 having a strike face generally designated by reference numeral 32 . As illustrated in FIGS. 4 , 4 A and 4 B, according to the present invention the strike face 32 is spherical and includes a concave dimple 36 with a cylindrical counterbore 38 leading into the dimple. The cylindrical counterbore 38 has a depth of at least about 0.001 inches ranging up to about 0.5 inches, and preferably is about 0.009 inches, and serves to prevent excessive flexing of the operating rod during firearm operation. In particular, the end of the operating rod may be provided with a convex surface generally complementary with the concave dimple. During the self loading process, the operating rod is subjected to considerable stress that can cause the rod to flex. If the rod flexes enough to contact the cylindrical counterbore 38 , the cylindrical shape of the counterbore will act as a support for the rod to prevent further flexing. The outermost edge 37 of the strike face also preferably has a chamfered portion 31 leading into the counterbore as best seen in FIG. 4B .
The strike face 32 , cylindrical counter bore 38 , outermost edge 37 and chamfered portion 31 are all made with a downward angle of between about 0.05° and about 5.0°, and is preferably about 0.3°. Hence, according to a preferred embodiment, the face, counterbore, edge and chamfer are all angled downwardly, with the angle 39 as measured from the outermost edge 37 to the center axis 34 of the carrier bore 16 being between about 89.95° and about 85.0°, as shown in FIG. 4A .
As already noted, the strike face 32 is contacted by the operating rod 40 of the weapon's gas operating system 42 when the weapon is fired. In sum, when the firearm 13 is fired, gas pressure entering the gas operating system 42 pushes the operating rod 40 rearwardly against the strike face 32 as indicated by arrow 50 shown in FIG. 5 . Gas vents 52 are located at the limit of the desired operating stroke to bleed off any excess gas, preventing over-stroking. The operating rod 40 delivers a buffered impulse to the bolt carrier 10 via the strike face 32 which carrier then moves rearwardly, rotating the bolt 22 and causing it to unlock and begin the cartridge extraction process. The downward angle of the strike face 32 and counterbore 38 counteracts the off-axis force exerted by the operating rod 40 so that downward tilt of the rear 27 of the bolt carrier 10 within the receiver is prevented.
As shown in FIG. 6 , the bolt carrier 10 , having more mass than the operating rod 40 , continues to move rearwardly after the operating rod “runs out of gas”, so to speak, and returns to battery under spring tension, independently of the bolt carrier motion. The bolt carrier thereafter returns to battery under the spring force of a buffer return spring (not shown) located in the stock.
In addition to the benefits of the angled strike face 32 and counterbore 38 in reducing carrier tilt, forming the carrier key 30 integrally with the carrier 10 reduces manufacturing complexity and cost. Particularly, forming the carrier key and the carrier as a single piece eliminates the need for exact machining of separate carrier and carrier key components otherwise needed to ensure a precise fit within close tolerances. With the single-piece construction, manufacture is simplified and manufacturing costs reduced.
Preferably, the rear 27 of the bolt carrier 10 is provided with a boss, generally designated by reference numeral 60 , having an outer diameter 62 larger than the main body 64 of the bolt carrier 10 with cuts or flutes 66 therein for water passage, as already discussed herein and in the Gomez application.
As shown in FIGS. 1 , 2 , 7 and 8 , the exterior of the bolt carrier 10 is provided with a series of longitudinally extending lands or rails, generally four, that include upper rails 70 and lower rails 72 . The lower rails 72 extend from the front face 26 of the bolt carrier 10 rearwardly for a distance of about one-half the length of the bolt carrier. According to the present invention, the upper rails 70 are made with extensions 74 that extend forwardly to also reach the front face 26 of the bolt carrier as shown in FIGS. 1 , 2 and 7 . The extensions 74 lie on either side of the charging handle engagement shelf 28 . The rails 70 , 72 , in conjunction with the boss 60 , support the front 29 and rear 27 respectively, of the bolt carrier 10 to prevent the bolt carrier from tilting and wearing on the receiver 12 during the normal operation of an M16 or related firearm.
Both the upper rails 70 and the lower rails 72 , shown in FIG. 8 , have debris relief cuts 80 formed therein. These cuts 80 provide a recess which captures any dirt and other debris that enters the receiver as the bolt carrier moves back and forth during firing. By accumulating the dirt, etc. in the recess 80 , the weapon is not stalled by such material but can continue to operate.
As noted earlier, the bolt carrier 10 is received within a receiver extension 41 which is shown in isolation in FIG. 9 . According to a further feature of the present invention, the bottom 15 and rear 17 of the receiver extension 41 are provided with drain holes 45 as shown in FIG. 9B for removal of water trapped in the receiver extension during over the beach operations. As noted earlier, as the weapon is fired, the bolt carrier moves rearwardly into the receiver extension 41 . Water present in the receiver extension is forced, by the pumping action created by the reciprocating movement of the bolt carrier, outwardly through the drain holes 45 in the bottom 15 and rear 17 of the receiver extension 41 to empty the receiver extension of water. In addition, water can pass through the flutes 66 in the boss 60 to exit the receiver by moving past the carrier as a result of the same pumping action created by the cycling of the bolt carrier during firing. Hence, a firearm equipped with the water-draining cuts 66 and the receiver extension drain holes 45 can be immediately fired upon exit from an aquatic environment and, in the process, will automatically self-empty the receiver extension of trapped water.
Finally, to improve the durability of the weapon, the operating rod 40 is made of super alloy with high nickel and cobalt content. Such construction produces a stronger operating rod that is able to withstand repeated firing, and the considerable stresses associated therewith, over a longer lifespan than conventional rods. The super alloy is a martensitic age hardening iron-based steel alloy, essentially carbon free, with nickel and cobalt as the main alloying elements, preferably in the range of about 15% to about 22% nickel and about 5% to 15% cobalt by weight of the total material composition. The super alloy may also include minor amounts of aluminum, titanium and/or molybdenum as interstitial alloying elements. Preferred compositions have about 17% to about 19% nickel, about 7% to about 12.5% cobalt as the main alloying elements, and about 0.05% to about 0.15% aluminum, about 0.3% to about 1.6% titanium and about 4.6% to about 5.2% molybdenum as interstitial alloying elements, all by weight, with the remainder being iron. Preferred super alloys are available from ATI Allvac of Monroe, N.C., under the names Maraging/VascoMax C-250, Maraging/VascoMax C-300, and Maraging/VascoMax C-350.
The foregoing descriptions and drawings should be considered as illustrative only of the principles of the invention. The invention may be configured in a variety of shapes and sizes and is not limited by the dimensions of the preferred embodiment. Numerous applications of the present invention will readily occur to those skilled in the art. Therefore, it is not desired to limit the invention to the specific examples disclosed or the exact construction and operation shown and described. Rather, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention. | A bolt carrier for use with the ARI5/MI6 family of firearms is provided. The bolt carrier includes an integrally formed carrier key and spherical strike face surrounded by a cylindrical counterbore made with a downward angle to act against the tilting force imparted by the operating rod of the firearm's gas operating system. The outer surface of the carrier includes upper and lower running rails that all extend fully to the front face of the carrier to lengthen the carrier's rail support or bearing surfaces against the receiver. | 5 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a reciprocating power tool and more particularly, to a mounting structure of a grip of a hand-held reciprocating power tool such as an electric hammer and hammer drill reciprocating a tool bit at a certain cycle.
[0003] 2. Description of the Related Art
[0004] Japanese non-examined laid-open Utility Model Publication No. 1-18306 (D1) discloses an electric hammer having a vibration-proof grip. In the known electric hammer, the grip that the user holds is connected via an elastic element made of rubber to a body of the hammer in which vibration is caused.
[0005] With such construction, vibration transmitted from the hammer body to the grip can be absorbed via the elastic element. In order to maximize the effect of absorbing vibration, the spring constant of the elastic element must be small. However, if the spring constant is small, the grip and the hammer body are held unsteady with respect to each other and therefore, the spring constant of the elastic element must be set large enough to avoid such unsteadiness.
SUMMARY OF THE INVENTION
[0006] Accordingly, it is an object of the invention to provide an effective technique for enhancing the effect of reducing vibration of a grip of a reciprocating power tool.
[0007] According to the present invention, a representative reciprocating power tool may comprise a tool bit that performs an operation by reciprocating in the axial direction, a tool body that houses an actuating mechanism for driving the tool bit, and a grip mounted on the rear end of the body on the side opposite to the tool bit. The “reciprocating power tool” typically comprises any tool of the type which performs an operation while the user holds the grip and applies a pressing force on the grip in the direction of the tool body. Specifically, the “reciprocating power tool” includes impact power tools such as an electric hammer and a hammer drill, which performs fracturing or drilling operation on a workpiece by causing a tool bit to perform only hammering movement in the axial direction or the hammering movement and rotation in the circumferential direction in combination. In addition to such impact power tools, it may include cutting tools such as a reciprocating saw or a jig saw, which performs a cutting operation on a workpiece by causing a blade to perform a reciprocating movement.
[0008] According to the invention, the grip is connected to the tool body via an elastic element and a vibration damping part. The elastic element is resiliently disposed between the tool body and the grip and serves to absorb vibration transmitted from the tool body to the grip ring operation. The vibration damping part is also disposed between the tool body and the grip and serves to damp and/or attenuate the vibration. Preferably, the direction of input of the biasing force of the elastic element and the direction of damping action of the vibration damping part may generally coincide with the direction of input of vibration or the axial direction of the tool bit. The “elastic element” may comprise a rubber or a spring.
[0009] Further, the manner of “damping vibration” typically includes the manner of damping vibration by utilizing frictional resistance that acts on the sliding parts when two elements move in contact with each other. Otherwise, the manner of damping vibration by utilizing resistance produced when fluid passes though an orifice within a space of which capacity varies by the relative movement of the two elements. According to the invention, because the vibration during the operation of the power too is reduced by the elastic element in association with the vibration damping part, the spring constant of the elastic element can be made smaller without causing unstable connection between the tool body and the grip. Therefore, vibration transmitted from the tool body to the grip during operation by the reciprocating power tool is effectively reduced by the vibration absorbing action caused by the elastic deformation of the elastic body and by the damping action of the vibration damping part.
[0010] Other objects, features and advantages of the present invention will be readily understood after reading the following detailed description together with the accompanying drawings and the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is a side view showing an entire electric hammer according to an embodiment of the invention.
[0012] FIG. 2 is a side sectional view, showing the construction for mounting the upper end portion of a handgrip to the body.
[0013] FIG. 3 is a partial plan sectional view of the handgrip.
[0014] FIG. 4 is a sectional view taken along line IV-IV in FIG. 3 .
[0015] PIG. 5 is an enlarged view of the circled part A in FIG. 4 .
[0016] FIG. 6 schematically shows the construction for mounting the handgrip to the body.
[0017] FIG. 7 schematically shows a modification of a vibration damping mechanism.
[0018] FIG. 8 schematically shows a modification of the vibration damping mechanism.
[0019] FIG. 9 schematically shows a modification of the vibration damping mechanism.
DETAILED DESCRIPTION OF THE INVENTION
[0020] Each of the additional features and method steps disclosed above and below may be utilized separately or in conjunction with other features and method steps to provide and manufacture improved reciprocating power tools and method for using such reciprocating power tools and devices utilized therein. Representative examples of the present invention, which examples utilized many of these additional features and method steps in conjunction, will now be described in detail with reference to the drawings. This detailed description is merely intended to teach a person skilled in the art further details for practicing preferred aspects of the present teachings and is not intended to limit the scope of the invention. Only the claims define the scope of the claimed invention. Therefore, combinations of features and steps disclosed within the following detailed description may not be necessary to practice the invention in the broadest sense, and are instead taught merely to particularly describe some representative examples of the invention, which detailed description will now be given with reference to the accompanying drawings.
[0021] A representative embodiment of the present invention will now be described with reference to the drawings. FIG. 1 is a side view of an entire electric hammer 101 as a representative embodiment of a reciprocating power tool according to the invention. As shown in FIG. 1 , the electric hammer 101 includes a body 103 . The body 103 is a feature that corresponds to the “tool body” according to the invention. The body 103 includes a motor housing 105 , a gear housing 107 and a tool holder 109 in the tip end (front end) region of the gear housing 107 . A hammer bit 111 is mounted in the tool holder 109 such that the hammer bit 111 can move in the axial direction with respect to the tool holder 109 and can rotate in the circumferential direction together with the tool holder 109 . The hammer bit 111 is a feature that corresponds to the “tool bit” according to the invention. Further, a handgrip 113 held by the user during operation is mounted on the rear end of the body 103 . In the embodiment, for the sake of convenience of explanation, the side of the hammer bit 11 is taken as the front side and the side of the handgrip 113 as the rear side.
[0022] An impact driving mechanism (not shown) is disposed within the body 103 and serves to transmit a striking movement to the hammer bit 111 retained by the tool holder 109 . The impact driving mechanism is know in the art and therefore will be explained only briefly. A driving motor as a source is disposed within the motor housing 105 . The rotating output of the driving motor is converted into reciprocating motion of a piston via a crank mechanism disposed within the gear housing 107 . When the piston linearly moves, a striker linearly moves toward the tip end (forward) at high speed by the action of a so-called air spring caused within the cylinder by the linear movement of the pistol. The striker then collides with an impact bolt as an intermediate element. The impact bolt, in turn, linearly moves forward at high speed and collides with the hammer bit 111 . The hammer bit 11 then linearly moves in the axial direction (forward) at high speed. Thus, the hammer bit 11 performs a striking (hammering) movement and as a result, hammering operation such as chipping is performed on a workpiece (not shown). The driving motor 113 is stud or stopped by operating a trigger 115 on the handgrip 113 to turn a power switch to the “ON” or “OFF” position.
[0023] The striker and the impact bolt form a striking mechanism which transmits a striking movement to the hammer bit 111 . The striking mechanism and the hammer bit 111 move linearly substantially along the same line. Upon striking movement of the hammer bit 111 , vibration is caused in the body 103 in the axial direction of the hammer bit 111 . In order to reduce transmission of such vibration to the handgrip 113 , the handgrip 113 is mounted to the body 103 in the following manner. The construction for mounting the handgrip 113 to the body 103 will now be explained with reference to FIGS. 1 to 6 . FIG. 2 is a partial side sectional view showing the construction for mounting the upper end portion of the handgrip 113 to the body 103 . FIG. 3 is a partial plan sectional view also showing the mounting construction of the upper end portion of the handgrip 113 . FIG. 4 is a sectional view taken along line IV-IV in FIG. 3 . FIG. 5 is an enlarged view of the circled part A in FIG. 4 . FIG. 6 schematically shows the construction for mounting the handgrip 113 to the body 103 .
[0024] The handgrip 113 comprises a synthetic resin covering 121 and a grip 123 . The covering 121 is arranged to cover the rear portion of the body 103 . The grip 123 comprises a metal portion and a synthetic resin potion joined together and is mounted to the covering 121 . The covering 121 is fastened to the rear portions of the gear housing 107 and motor housing 105 which form the body 103 , by screws (not shown) at predetermined several points. Therefore, the covering 121 is secured to the body 103 and substantially defined as a member on the body 103 side.
[0025] As shown in FIGS. 1 and 2 , the grip 123 extends vertically in a direction crossing the axial direction of the hammer bit 111 . Mounting legs 123 a and 123 b extend a predetermined length from the extending ends or the upper and lower ends of the grip 123 in a direction generally parallel to the axial direction of the hammer bit 111 (in a horizontal direction). The grip 123 having the mounting legs 123 a, 123 b is thus generally U-shaped in side view. As schematically shown in FIG. 6 , the upper end mounting leg 123 a is connected to the body 103 via an elastic element in the form of a coil spring 131 and a vibration damping mechanism 141 . The lower end mounting leg 123 b is connected to tile body 103 via a pivot 127 such that it can pivot with respect to the body 103 . The construction for mounting the mounting legs 123 a, 123 b will now be explained.
[0026] As shown in FIGS. 2 and 3 , the coil spring 131 is resiliently disposed between the mounting leg 123 a on the upper end of the grip 123 and the gear housing 107 and serves to absorb vibration of the grip 123 during operation. The coil spring 131 is a feature that corresponds to the “elastic element” according to the invention. The coil spring 131 is disposed such that the direction of action of its spring force generally coincides with the axial direction of the hammer bit 111 or the direction of input of vibration. The coil spring 131 is disposed in a position near a line of travel P of the reciprocating hammer bit 111 or in a position slightly above a line of extension of the axis of the hammer bit 111 . One end of the coil spring 131 is supported by a spring receiver 133 on the grip 123 side. The other end of the coil spring 131 extends into the gear housing 107 through the covering 121 and is supported by a spring receiver 135 fixed on the gear housing 107 . The mounting leg 123 a on the upper end of the grip 123 is thus connected to the body 103 via the coil spring 131 . The spring receiver 133 on the grip 123 side also serves to hold an elastic cover 137 which will be described below.
[0027] The mounting leg 123 b on the lower end of the grip 123 is connected to the rear lower end of the covering 121 via the pivot 127 such that it can pivot on the horizontal pivot with respect to the body 103 . The grip 123 is designed such that the direction of the relative pivotal movement via the pivot 127 generally coincides with the axial direction of the hammer bit 111 or the direction of input of vibration. With such construction, the vibration absorbing function of the coil spring 131 is effectively performed with respect to the vibration in the axial direction of the hammer bit 111 transmitted from the body 103 to the grip 123 via the covering 121 .
[0028] Further, as shown in FIGS. 3 and 4 , the mounting leg 123 a on the upper end of the grip 123 is connected to the covering 121 on the body 103 side via the vibration damping mechanism 141 that damps and attenuates vibration by means of friction. The vibration damping mechanism 141 is a feature that corresponds to the “vibration damping part” according to the invention. The vibration damping mechanism 141 comprises a rod-like element 143 and a cylindrical element 145 that move (pivot on the pivot 127 ) with respect to each other. The rod-like element 143 is a feature that corresponds to the “grip-side sliding part” and the “first element”, and the cylindrical element 145 corresponds to the “body-side sliding part” and the “second element” according to the invention. The rod-like element 143 is a linear element that is integrally formed with the mounting leg 123 a on the upper end of the grip 123 . The rod-like element 143 extends generally parallel to the travel line P of the hammer bit 111 (and thus generally parallel to the coil spring 131 ) from the mounting leg 123 a toward the gear housing 107 . The rod-like element 143 is inserted into the bore of the cylindrical element 145 integrally formed with the covering 121 such that the rod-like element 143 can move with respect to the cylindrical element 145 . Further, a stopper bolt 149 is screwed into the rod-like element 143 from the covering 121 side and a head 149 a of the stopper bolt 149 contacts the end surface of the cylindrical element 145 , so that the rod-like element 143 is prevented from coming off.
[0029] The rod-like element 143 and the cylindrical element 145 are disposed on the both sides of the coil spring 131 . As shown in FIG. 4 , the rod-like element 143 and the cylindrical element 145 have a generally oval section having flat side surfaces or width across flats. Specifically, the outer surface of the rod-like element 143 and the inner surface of the cylindrical element 145 have side regions configured as vertical flat surfaces 143 a, 145 a and upper and lower regions configured as circular arc surfaces 143 b, 145 b. As shown in FIG. 5 in enlarged view, a predetermined clearance is provided between the outer surface of the rod-like element 143 and the inner surface of the cylindrical element 145 . Thus, the rod-like element 143 is loosely fitted into the cylindrical element 145 . A projection 147 is formed on one of the flat surface 143 a or side region of the rod-like element 143 and the flat surface 145 a or side region of the cylindrical element 145 . In this embodiment, the projection 147 is formed on the flat surface 143 a of the rod-like element 143 and contacts the flat surface 145 a of the cylindrical element 145 . The projection 147 causes friction (resistance to the sliding movement) by sliding in contact with the flat surface 145 a of the cylindrical element 145 when the rod-like element 143 moves with respect to the cylindrical element 145 . By this friction, vibration which is transmitted from the body 103 to the grip 123 during operation is damped. The projection 147 and the flat surface 145 a of the cylindrical element 145 which contacts the projection 147 are features that correspond to the “sliding part” according to the invention.
[0030] The relative movement of the rod-like element 143 and the cylindrical element 145 is defined by a pivotal movement around the pivot 127 . Therefore, the clearance between the circular arc surface 143 b of the rod-like element 143 and the circular arc surface 145 b of the cylindrical element 145 is designed to be large enough to avoid interference between the rod-like element 143 and the cylindrical element 145 .
[0031] The coil spring 131 and the vibration damping mechanism 141 are covered with a rubber elastic cover 137 disposed between the mounting leg 123 a on the upper end of the grip 123 and the covering 121 . The elastic cover 137 has a bellows-like cylindrical shape. One open edge of the elastic cover 137 is fitted on the inner surface of the mounting leg 123 a and anchored by the spring receiver 133 on the mounting leg 123 side. The other open edge of the elastic cover 137 is fastened by engaging with an annular engaging groove 139 that is formed in the covering 121 .
[0032] Operation and usage of the electric hammer 101 constructed as described above will now be explained. When the trigger 115 is depressed to turn on the power switch and the driving motor 113 is driven, the rotating output of the driving motor is converted into linear motion via the crank mechanism, as mentioned above. Further, the linear motion is transmitted to the hammer bit 111 as striking movement via the striking mechanism that comprises the striker and the impact bolt. Thus, the hammering operation is performed on the workpiece. The hammering operation by the electric hammer 101 is performed while the user holds the grip 123 and applies a pressing force on the grip 123 in the direction of the body 103 . When the pressing force is applied to the grip 123 , the mounting leg 123 a on the upper end of the grip 123 rotates toward the body 103 (forward) around the pivot 127 . At this time, the coil spring 131 is compressed and deformed, and the head 149 a of the stopper bolt 149 is caused to move apart from the cylindrical element 145 together with the rod-like element 143 . Thus, the grip 123 is allowed to pivot in the both directions around the pivot 127 with respect to the body 103 .
[0033] During such hammering operation by the electric hammer 101 , impulsive and cyclic vibration is caused in the body 103 when the hammer bit 111 is driven. The input of such vibration from the body 103 to the grip 123 is reduced and attenuated by the vibration absorbing action caused by elastic deformation of the coil spring 131 and by the vibration damping action caused by friction of the vibration damping mechanism 141 . Specifically, in the vibration damping mechanism 141 , friction (force of inhibiting relative movement) acts upon the contact part between the projection 147 of the rod-like element 143 and the flat surface 145 a of the cylindrical element 145 which produce sliding friction in contact with each other. By this friction, the vibration damping mechanism 141 damps vibration which is to be transmitted to the grip 123 via the coil spring 131 . The coil spring 131 has a property of keeping rocking once it starts to rock. According to this embodiment, however, the rock of the coil spring 131 is controlled by friction of the vibration damping mechanism 141 . Thus, the input of vibration from the body 103 to the grip 123 can be effectively reduced by the vibration absorbing action of the coil spring 131 and by the damping action caused by friction of the vibration damping mechanism 141 . The degree of damping of the vibration damping mechanism 141 can be adjusted by changing the magnitude of friction that acts upon the contact part between the projection 147 and the flat surface 145 a during sliding contact. Specifically, the magnitude of friction can be changed, for example, by changing the surface roughness, materials or area of the contact part or by changing the force acting upon the contact part in the direction perpendicular to the direction of movement.
[0034] Further, in this embodiment, the grip 123 is connected to the body 103 in a position near the source of vibration (near the travel line P of the hammer bit 111 ) via the coil spring 131 and the vibration damping mechanism 141 . The grip 123 is also connected to the body 103 in a position remote from the source of vibration via the pivot 127 such that it can pivot in the direction of input of vibration with respect to the body 103 . Thus, the vibration absorbing function of the coil spring 131 and the vibration damping function of the vibration damping mechanism 141 can be effectively performed. Further, the vibration damping mechanism 141 is disposed on the both sides of the coil spring 131 or on the both sides of the travel line P of the hammer bit 111 . Therefore, movements are produced on the both sides around an axis perpendicular to the travel line P of the hammer bit 111 by the sliding contact between the projection 147 of the rod-like element 143 and the flat surface 145 a of the cylindrical element 145 , and such moments act in a manner of canceling each other out. As a result, undesired generation of moments due to provision of the vibration damping mechanism 141 is avoided.
[0035] Further, by the combined use of the coil spring 131 and the vibration damping mechanism 141 , the spring constant of the coil spring 131 can be freely and easily chosen without need of considering the “unsteadiness” which may be caused between the grip 123 and the body 103 if the grip 123 is connected to the body 103 only by the coil spring 131 .
[0036] Further, in this embodiment, with the construction in which the body 103 and the grip 123 are joined to each other via the pivot 127 , they are prevented from relative movement except for the pivotal movement around the pivot 127 . Therefore, the contact between the projection 147 of the rod-like element 143 and the flat surface 145 a of the cylindrical element 145 can be held in a constant state, so that the friction in the sliding part can be stabilized. Further, the sliding part that comprises the projection 147 and the flat surface 145 a is provided on the side regions of the rod-like element 143 and the cylindrical element 145 . Thus, the sliding part can be linearly configured on the rod-like element 143 and the cylindrical element 145 that pivot on the pivot 127 with respect to each other. Therefore, the sliding contact part can be easily provided while maintaining stable friction.
[0037] Now, modifications of the vibration damping mechanism 141 will be explained with reference to FIGS. 7 to 9 .
[0038] In the above-mentioned embodiment, the cylindrical element 145 made of synthetic resin is in frictional contact with the rod-like element 143 made of metal. However, in the modification shown in FIG. 7 , the rubber elastic cover 137 is in frictional contact with the metal rod-like element 143 . Specifically, an arm 151 is integrally formed with the elastic cover 137 and extends toward the rod-like element 143 . The end of the arm 151 is pressed against the rod-like element 143 by a predetermined pressing force from a direction crossing the direction of movement of the rod-like element 143 . In this state, the arm 151 slides with respect to the rod-like element 143 . In another modification shown in FIG. 8 , an O-ring 153 is additionally disposed on the engaging surface between the rod-like element 143 and the cylindrical element 145 in the above-mentioned embodiment. According to the modifications shown in FIGS. 7 and 8 , by utilizing the elastic deformation of the arm 151 and the O-ring 153 , a required biasing force can be applied to the sliding surface in a direction crossing the sliding direction. Further, the pivotal movement of the rod-like element 143 around the pivot 127 can be accommodated by the elastic deformation. Therefore, the rod-like element 143 may have, for example, a simple circular shape in section in order to enhance the manufacturability.
[0039] Further, according to a different modification as shown in FIG. 9 , the vibration damping mechanism 141 comprises a fluid damper 155 . The fluid damper 155 includes a cylinder 156 mounted on the body 103 and a piston 157 mounted on the grip 123 . The piston 157 moves within the cylinder 156 when the body 103 and the grip 123 move with respect with each other. At this time, fluid resistance of the fluid passing through an orifice 158 within the cylinder 156 is utilized as a vibration damping force. Further different constructions other than the above-mentioned modifications can also be applied. For example, a plate spring or a resin spring may be provided and engaged with the friction sliding surface of the rod-like element 143 while applying the biasing force in a direction perpendicular to the direction of movement of the rod-like element 143 .
[0040] Instead of utilizing the coil spring 131 as an elastic element, a rubber may be used. Further, as to the mounting leg 123 b on the lower end of the grip 123 rotatably connected to the body via the pivot 127 , it may be connected to the body via the coil spring 131 and the vibration damping mechanism 141 in the same manner as the mounting leg 123 a on the upper end
[0041] Further, the friction sliding part is formed by the projection 147 and the flat surface 145 a in this embodiment, but it may be formed by opposed flat surfaces. As for the projection 147 provided between the rod-like element 143 and the cylindrical element 145 , one or more projections 147 may be provided between each paw of the opposed flat surfaces 147 , or the projections 147 may continuously extend in the direction of the relative movement. In this case, the surface of the projecting end of the projection 147 which contacts the opposed flat surface 145 a may comprise a flat surface or a spherical surface.
[0042] Further, in this embodiment, the electric hammer is described as a representative example of the reciprocating power tool. However, the invention may also be applied to a hammer drill which performs a drilling operation on a workpiece by causing a tool bit or a hammer bit to perform hammering movement in the axial direction and rotation in the circumferential direction. In addition to the impact power tools such as an electric hammer and a hammer drill, the invention may also be applied to cutting tools such as a reciprocating saw or a jig saw which perform a cutting operation on a workpiece by causing a tool bit or a blade to perform a reciprocating movement.
[0043] Further, the vibration damping part may be disposed on the both sides of a travel line of the tool bit. With such construction, moments produced on the both sides around an axis perpendicular to the travel line of the tool bit by the vibration damping action of the vibration damping part are canceled out to each other. As a result, undesired generation of moments due to provision of the vibration damping mechanism is avoided. Further, the vibration damping part may be disposed on the both sides of the travel line of the tool bit typically in such a manner that the sliding surfaces on the both sides of the travel line extend parallel to each other.
[0044] It is explicitly stated that all features disclosed in the description and/or the claims are intended to be disclosed separately and independently from each other for the purpose of original disclosure as well as for the purpose of restricting the claimed invention independent of the composition of the features in the embodiments and/or the claims. It is explicitly stated that all value ranges or indications of groups of entities disclose every possible intermediate value or intermediate entity for the purpose of original disclosure as well as for the purpose of restricting the claimed invention, in particular as limits of value ranges.
DESCRIPTION OF NUMERALS
[0000]
101 electric hammer (reciprocating power tool)
103 body (tool body)
105 motor housing
107 gear housing
109 tool holder
111 hammer bit (tool bit)
113 handgrip
115 trigger
121 covering
123 grip
123 a mounting leg on the upper end
123 b mounting leg on the lower end
127 pivot
131 coil spring
133 spring receiver
135 spring receiver
137 elastic cover
139 engaging groove
141 vibration damping mechanism (vibration damping part)
143 rod-like element
143 a flat surface
143 b circular arc surface
145 cylindrical element
145 a flat surface
145 b circular arc surface
147 projection (sliding part)
149 stopper bolt
149 a head
151 arm
153 O-ring
155 fluid damper
156 cylinder
157 piston
158 orifice | It is an object of the invention to provide an effective technique for enhancing the effect of reducing vibration of a grip of a reciprocating power tool. According to the present invention, a representative reciprocating power tool may comprise a tool bit, a tool body and a grip. The grip is connected to the tool body via an elastic element and a vibration damping part. The elastic element is resiliently disposed between the tool body and the grip and serves to absorb vibration transmitted from the tool body to the grip during operation. The vibration damping part is disposed between the tool body and the grip and serves to damp and/or attenuate the vibration. According to the invention, the spring constant of the elastic element can be made smaller due to vibration damping part. | 1 |
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