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CROSS-REFERENCES TO RELATED APPLICATIONS [0001] This application is a continuation-in-part of the following application: U.S. patent application entitled FOLDED WALL ANCHOR AND SURFACE-MOUNTED ANCHORING filed recently. BACKGROUND OF THE INVENTION [0002] 1. Field of the Invention [0003] This invention relates to wall anchor constructs and to surface-mounted anchoring systems employing the same, both of which are used in cavity walls. More particularly, the invention relates to sheetmetal wall anchors and wire formative veneer ties that comprise positive interlocking components of the anchoring system. The system has application to seismic-resistant to cavity walls and other structures having special requirements. The latter include high-strength requirements for jumbo brick and stone block veneers and high-span requirements for larger cavities with thick insulation. [0004] 2. Description of the Prior Art [0005] In the late 1980's, surface-mounted wall anchors were developed by Hohmann & Barnard, Inc., patented under U.S. Pat. No. 4,598,518 of the first-named inventor hereof. The invention was commercialized under trademarks DW-10, DW-10-X, and DW-10-HS. These widely accepted building specialty products were designed primarily for dry-wall construction, but were also used with masonry backup walls. For seismic applications, it was common practice to use these wall anchor as part of the DW-10 Seismiclip interlock system which added a Byna-Tie wire formative, a Seismiclip snap-in device—described in U.S. Pat. No. 4,875,319 ('319), and a continuous wire reinforcement. [0006] In the dry wall application, the surface-mounted wall anchor of the above-described system has pronged legs that pierce the insulation and the wall board and rest against the metal stud to provide mechanical stability in a four-point landing arrangement. The vertical slot of the wall anchor enables the mason to have the wire tie adjustably positioned along a pathway of up to 3.625-inch (max.). The interlock system served well and received high scores in testing and engineering evaluations which examined the effects of various forces, particularly lateral forces, upon brick veneer masonry construction. However, under certain conditions, the system did not sufficiently maintain the integrity of the insulation. [0007] The engineering evaluations further described the advantages of having a continuous wire embedded in the mortar joint of anchored veneer wythes. The seismic aspects of these investigations were reported in the inventor's '319 patent. Besides earthquake protection, the failure of several high-rise buildings to withstand wind and other lateral forces resulted in the incorporation of a for continuous wire reinforcement requirement in the Uniform Building Code provisions. The use of a continuous wire in masonry veneer walls has also been found to provide protection against problems arising from thermal expansion and contraction and to improve the uniformity of the distribution of lateral forces in the structure. [0008] Shortly after the introduction of the pronged wall anchor, a seismic veneer anchor, which incorporated an L-shaped backplate, was introduced. This was formed from either 12- or 14-gauge sheetmetal and provided horizontally disposed openings in the arms thereof for pintle legs of the veneer anchor. In general, the pintle-receiving sheetmetal version of the Seismiclip interlock system served well, but in addition to the insulation integrity problem, installations were hampered by mortar buildup interfering with pintle leg insertion. [0009] In the 1980's, an anchor for masonry veneer walls was developed and described in U.S. Pat. No. 4,764,069 by Reinwall et al., which patent is an improvement of the masonry veneer anchor of Lopez, U.S. Pat. No. 4,473,984. Here the anchors are keyed to elements that are installed using power-rotated drivers to deposit a mounting stud in a cementitious or masonry backup wall. Fittings are then attached to the stud which include an elongated eye and a wire tie therethrough for deposition in a bed joint of the outer wythe. It is instructive to note that pin-point loading—that is forces concentrated at substantially a single point—developed from this design configuration. Upon experiencing lateral forces over time, this resulted in the loosening of the stud. [0010] Exemplary of the public sector building specification is that of the Energy Code Requirement, Boston, Mass. (see Chapter 13 of 780 CMR, Seventh Edition). This Code sets forth insulation R-values well in excess of prior editions and evokes an engineering response opting for thicker insulation and correspondingly larger cavities. Here, the emphasis is upon creating a building envelope that is designed and constructed with a continuous air barrier to control air leakage into or out of conditioned space adjacent the inner wythe. [0011] As insulation became thicker, the tearing of insulation during installation of the pronged DW-10X wall anchor, see supra, became more prevalent. This occurred as the installer would fully insert one side of the wall anchor before seating the other side. The tearing would occur during the arcuate path of the insertion of the second leg. The gapping caused in the insulation permitted air and moisture to infiltrate through the insulation along the pathway formed by the tear. While the gapping was largely resolved by placing a self-sealing, dual-barrier polymeric membrane at the site of the legs and the mounting hardware, with increasing thickness in insulation, this patchwork became less desirable. The improvements hereinbelow in surface mounted wall anchors look toward greater retention of insulation integrity and less reliance on a patch. [0012] Another prior art development occurred shortly after that of Reinwall/Lopez when Hatzinikolas and Pacholok of Fero Holding Ltd. introduced their sheetmetal masonry connector for a cavity wall. This device is described in U.S. Pat. Nos. 5,392,581 and 4,869,043. Here a sheetmetal plate connects to the side of a dry wall column and protrudes through the insulation into the cavity. A wire tie is threaded through a slot in the leading edge of the plate capturing an insulative plate thereunder and extending into a bed joint of the veneer. The underlying sheetmetal plate is highly thermally conductive, and the '581 patent describes lowering the thermal conductivity by foraminously structuring the plate. However, as there is no thermal break, a concomitant loss of the insulative integrity results. [0013] In recent building codes for masonry structures a trend away from eye and pintle structures is seen in that newer codes require adjustable anchors be detailed to prevent disengagement. This has led to anchoring systems in which the open end of the veneer tie is embedded in the corresponding bed joint of the veneer and precludes disengagement by vertical displacement. [0014] In the past, the use of wire formatives have been limited by the mortar layer thicknesses which, in turn are dictated either by the new building specifications or by pre-existing conditions, e.g. matching during renovations or additions the existing mortar layer thickness. While arguments have been made for increasing the number of the fine-wire anchors per unit area of the facing layer, architects and architectural engineers have favored wire formative anchors of sturdier wire. [0015] Contractors found that heavy wire anchors, with diameters approaching the mortar layer height specification, frequently result in misalignment. This led to the low-profile wall anchors of the inventors hereof as described in U.S. Pat. No. 6,279,283. However, the above-described technology did not address the adaption thereof to surface mounted devices. [0016] In the course of prosecution of U.S. Pat. No. 4,598,518 (Hohmann '518) several patents, indicated by an asterisk on the tabulation below, became known to the inventors hereof and are acknowledged hereby. Thereafter and in preparing for this disclosure, the additional patents which became known to the inventors are discussed further as to the significance thereof: Patent Inventor O. Cl. Issue Date 2,058,148* Hard 52/714 October, 1936 2,966,705* Massey 52/714 January, 1961 3,377,764 Storch Apr. 16, 1968 4,021,990* Schwalberg 52/714 May 10, 1977 4,305,239* Geraghty 52/713 December, 1981 4,373,314 Allan Feb. 15, 1983 4,438,611* Bryant 52/410 March, 1984 4,473,984 Lopez Oct. 2, 1984 4,598,518 Hohmann Jul. 8, 1986 4,869,038 Catani Sep. 26, 1989 4,875,319 Hohmann Oct. 24, 1989 5,392,581 Hatzinikolas et al. Feb. 28, 1995 5,408,798 Hohmann Apr. 25, 1995 5,456,052 Anderson et al. Oct. 10, 1995 5,816,008 Hohmann Oct. 15, 1998 6,209,281 Rice Apr. 3, 2001 6,279,283 Hohmann et al. Aug. 28, 2001 Foreign Patent Documents    279209* CH 52/714 March, 1952   2069024* GB 52/714 August, 1981 [0017] It is noted that with some exceptions these devices are generally descriptive of wire-to-wire anchors and wall ties and have various cooperative functional relationships with straight wire runs embedded in the inner and/or outer wythe. [0018] U.S. Pat. No. 3,377,764—D. Storch—Issued Apr. 16, 1968 [0019] Discloses a bent wire, tie-type anchor for embedment in a facing exterior wythe engaging with a loop attached to a straight wire run in a backup interior wythe. [0020] U.S. Pat. No. 4,021,990—B. J. Schwalberg—Issued May 10, 1977 [0021] Discloses a dry wall construction system for anchoring a facing veneer to wallboard/metal stud construction with a pronged sheet-metal anchor. Like Storch '764, the wall tie is embedded in the exterior wythe and is not attached to a straight wire run. [0022] U.S. Pat. No. 4,373,314—J. A. Allan—Issued Feb. 15, 1983 [0023] Discloses a vertical angle iron with one leg adapted for attachment to a stud; and the other having elongated slots to accommodate wall ties. Insulation is applied between projecting vertical legs of adjacent angle irons with slots being spaced away from the stud to avoid the insulation. [0024] U.S. Pat. No. 4,473,984—Lopez—Issued Oct. 2, 1984 [0025] Discloses a curtain-wall masonry anchor system wherein a wall tie is attached to the inner wythe by a self-tapping screw to a metal stud and to the outer wythe by embedment in a corresponding bed joint. The stud is applied through a hole cut into the insulation. [0026] U.S. Pat. No. 4,869,038—M. J. Catani—Issued 091/26/89 [0027] Discloses a veneer wall anchor system having in the interior wythe a truss-type anchor, similar to Hala et al. '226, supra, but with horizontal sheetmetal extensions. The extensions are interlocked with bent wire pintle-type wall ties that are embedded within the exterior wythe. [0028] U.S. Pat. No. 4,879,319—R. Hohmann—Issued Oct. 24, 1989 [0029] Discloses a seismic construction system for anchoring a facing veneer to wallboard/metal stud construction with a pronged sheet-metal anchor. Wall tie is distinguished over that of Schwalberg '990 and is clipped onto a straight wire run. [0030] U.S. Pat. No. 5,392,581—Hatzinikolas et al.—Issued Feb 28, 1995 [0031] Discloses a cavity-wall anchor having a conventional tie wire for mounting in the brick veneer and an L-shaped sheetmetal bracket for mounting vertically between side-by-side blocks and horizontally on atop a course of blocks. The bracket has a slit which is vertically disposed and protrudes into the cavity. The slit provides for a vertically adjustable anchor. [0032] U.S. Pat. No. 5,408,798—Hohmann—Issued Apr. 25, 1995 [0033] Discloses a seismic construction system for a cavity wall having a masonry anchor, a wall tie, and a facing anchor. Sealed eye wires extend into the cavity and wire wall ties are threaded therethrough with the open ends thereof embedded with a Hohmann '319 (see supra) clip in the mortar layer of the brick veneer. [0034] U.S. Pat. No. 5,456,052—Anderson et al.—Issued Oct. 10, 1995 [0035] Discloses a two-part masonry brick tie, the first part being designed to be installed in the inner wythe and then, later when the brick veneer is erected to be interconnected by the second part. Both parts are constructed from sheetmetal and are arranged on substantially the same horizontal plane. [0036] U.S. Pat. No. 5,816,008—Hohmann—Issued Oct. 15, 1998 [0037] Discloses a brick veneer anchor primarily for use with a cavity wall with a drywall inner wythe. The device combines an L-shaped plate for mounting on the metal stud of the drywall and extending into the cavity with a T-head bent stay. After interengagement with the L-shaped plate the free end of the bent stay is embedded in the corresponding bed joint of the veneer. [0038] U.S. Pat. No. 6,209,281—Rice—Issued Apr. 3, 2001 [0039] Discloses a masonry anchor having a conventional tie wire for mounting in the brick veneer and sheetmetal bracket for mounting on the metal-stud-supported drywall. The bracket has a slit which is vertically disposed when the bracket is mounted on the metal stud and, in application, protrudes through the drywall into the cavity. The slit provides for a vertically adjustable anchor. [0040] U.S. Pat. No. 6,279,283—Hohmann et al.—Issued Aug 28, 2001 [0041] Discloses a low-profile wall tie primarily for use in renovation construction where in order to match existing mortar height in the facing wythe a compressed wall tie is embedded in the bed joint of the brick veneer. [0042] None of the above provide the high-strength, surface-mounted wall anchor or anchoring systems utilizing these devices of this invention. As will become clear in reviewing the disclosure which follows, the cavity wall structures benefit from the recent developments described herein that lead to solving the problems of insulation integrity, of interference from excess mortar, and of high-span applications. In the related Application, wire formatives are compressively reduced in height at the junctures between the wall reinforcements and the wall anchors and various techniques of forming junctures between embedded wire formatives are introduced. SUMMARY [0043] In general terms, the invention disclosed hereby is a surface mounted wall anchor and an anchoring system employing the same. The wall anchor is a sheetmetal construct device which is described herein as functioning with various wire formative veneer ties. The two-and three-piece construction of the wall ties hereof enable the junctures of the legs and the base of the wall anchor to be located inboard from the periphery of the wall anchor. During formation of the wall anchor, the underside of the base is maintained as a flat, planar surface. Upon installation, the element(s) forming the flat base act to seal the insertion point where the legs enter into the exterior layer of building materials on the inner wythe. This sealing effect precludes the penetration of air, moisture, and water vapor through the insulation and/or wallboard, as the case may be, into the rest of the inner wythe structure. [0044] In the first embodiment, the two-piece wall anchor is an improvement of the earlier inventions of Schwalberg, U.S. Pat. No. 4,021,990 and of Hohmann, U.S. Pat. No. 4,875,319, see supra. Here it is seen that the two-piece wall anchor (with legs moved inboard) together with a swaged veneer tie and wire reinforcement in the outer wythe creates a seismic construct of superior strength. This construct is applied to a dry wall inner wythe having thick insulation over wallboard, a larger-than-normal cavity, and a facing of jumbo brick. [0045] In the second and third embodiments, the wall anchor constructs are of the winged variety. The wings in the second embodiment are perforated and permit selectively adjustable positioning of the veneer tie. Here a wall anchor construct together with a standard box veneer tie is applied to a dry wall inner wythe having interior insulation and, thus, the wall anchor legs have only to penetrate the wallboard layer. In the third embodiment, the wings are slotted with a centrally disposed reinforcement bar. The two-piece wall anchor is paired with a canted, low-profile veneer anchor. The two-piece wall anchor is surface-mounted to a masonry block inner wythe having insulation on the exterior surface and a brick facing. The use of innovative family of surface-mounted wall anchors in various applications address the problems of insulation integrity, thermal conductivity, and pin-point loading encountered in the previously discussed prior art. OBJECTS AND FEATURES OF THE INVENTION [0046] Accordingly, it is the primary object of the present invention to provide a new and novel anchoring systems for cavity walls, which systems are surface mountable to the backup wythe thereof. [0047] It is another object of the present invention to provide a new and novel wall anchor mounted on the exterior surface of the wall board or the insulation layer and secured to the metal stud or standard framing member of a dry wall construction. [0048] It is yet another object of the present invention to provide an anchoring system which is detailed to prevent disengagement under seismic or other severe environmental conditions. [0049] It is still yet another object of the present invention to provide an anchoring system which is constructed to maintain insulation integrity by preventing air and water penetration. [0050] It is a feature of the present invention that the two-piece wall anchor constructs hereof have planar baseplates for sealing against the leg insertion points. [0051] It is another feature of the present invention that the legs of the wall anchors hereof have only point contact with the metal studs with substantially no resultant thermal conductivity. [0052] It is yet another feature of the present invention that the bearing area between the wall anchor and the veneer tie spreads the forces thereacross and avoids pin-point loading. [0053] Other objects and features of the invention will become apparent upon review of the drawing and the detailed description which follows. BRIEF DESCRIPTION OF THE DRAWING [0054] In the following drawing, the same parts in the various views are afforded the same reference designators. [0055] [0055]FIG. 1 shows a first embodiment of this invention and is a perspective view of a surface-mounted anchoring system as applied to a cavity wall having a larger-than-normal cavity with an inner wythe of dry wall construction having thick insulation in the cavity and an outer wythe of brick; [0056] [0056]FIG. 2 is a rear perspective view showing the wall anchor construct of the surface-mounted anchoring system of FIG. 1; [0057] [0057]FIG. 3 is a perspective view of the surface-mounted anchoring system of FIG. 1 shown with a two-piece wall anchor, a swaged veneer tie threaded therethrough, and a reinforcing wire for seismic protection; [0058] [0058]FIG. 4 is a cross sectional view of FIG. 1 which shows the relationship of the surface-mounted anchoring system of this invention to the dry wall construction and to the brick outer wythe; [0059] [0059]FIG. 5 is a perspective view of a second embodiment of this invention showing a surface-mounted anchoring system for a cavity wall and is similar to FIG. 1, but shows a dry wall construction with interior insulation and a wall anchor construct with perforated wings with a box veneer tie for insertion into the bed joints of the brick veneer facing wall; [0060] [0060]FIG. 6 is a rear perspective view showing the wall anchor construct with perforated wings of FIG. 5; [0061] [0061]FIG. 7 is a partial perspective view of FIG. 5 showing the relationship of the wall anchor construct with perforated wings and the corresponding veneer tie; [0062] [0062]FIG. 8 is a perspective view of a third embodiment of this invention showing a surface-mounted anchoring system for a cavity wall and is similar to FIG. 1, but shows a masonry block backup wall with a wall anchor construct with slotted wings and a low-profile, canted veneer tie. [0063] [0063]FIG. 9 is a rear perspective view showing the wall anchor construct with slotted wings of FIG. 8; and, [0064] [0064]FIG. 10 is a partial perspective view of FIG. 8 showing the relationship of the wall anchor construct and the corresponding veneer tie. DESCRIPTION OF THE PREFERRED EMBODIMENTS [0065] Before entering into the detailed Description of the Preferred Embodiments, several terms which will be revisited later are defined. These terms are relevant to discussions of innovations introduced by the improvements of this disclosure that overcome the deficits of the prior art devices. [0066] In the embodiments described hereinbelow, the inner wythe is provided with insulation. In the dry wall construction, this takes the form, in one embodiment, of exterior insulation disposed on the outer surface of the inner wythe and, in another embodiment, of interior insulation disposed between the metal columns of the inner wythe. In the masonry block backup wall construction, insulation is applied to the outer surface of the masonry block. Recently, building codes have required that after the anchoring system is installed and, prior to the inner wythe being closed up, that an inspection be made for insulation integrity to ensure that the insulation prevents infiltration of air and moisture. Here the term insulation integrity is used in the same sense as the building code in that, after the installation of the anchoring system, there is no change or interference with the insulative properties and concomitantly substantially no change in the air and moisture infiltration characteristics. [0067] In a related sense, prior art sheetmetal anchors have formed a conductive bridge between the wall cavity and the interior of the building. Here the terms thermal conductivity and thermal conductivity analysis are used to examine this phenomenon and the metal-to-metal contacts across the inner wythe. [0068] Anchoring systems for cavity walls are used to secure veneer facings to a building and overcome seismic and other forces, i.e. wind shear, etc. In the past, some systems have experienced failure because the forces have been concentrated at substantially a single point. Here, the term pin-point loading refers to an anchoring system wherein forces are concentrated at a single point. [0069] In addition to that which occurs at the facing wythe, attention is further drawn to the construction at the exterior surface of the inner or backup wythe. Here there are two concerns. namely, maximizing the strength of the securement of the surface-mounted wall anchor to the backup wall and, as previously discussed minimizing the interference of the anchoring system with the insulation. The first concern is addressed using appropriate fasteners such as, for mounting to masonry block, the properly sized concrete threaded anchors with expansion sleeves or concrete expansion bolts and, for mounting to metal, dry-wall studs, self-tapping screws. The latter concern is addressed by the flatness of the base of the surface-mounted, wall anchor construct which surround the openings formed by the legs (the profile is seen in the cross-sectional drawing FIG. 4). [0070] In the detailed description, the veneer reinforcements and the veneer anchors are wire formatives, the wire used in the fabrication of veneer joint reinforcement conforms to the requirements of ASTM Standard Specification A951-00, Table 1. For the purpose fo this application tensile strength tests and yield tests of veneer joint reinforcements are, where applicable, those denominated in ASTM A-951-00 Standard Specification for Masonry Joint Reinforcement. [0071] Referring now to FIGS. 1 through 4, the first embodiment shows a surface-mounted anchoring system suitable for seismic zone applications. This anchoring system, discussed in detail hereinbelow, has a two-piece wall anchor, an interengaging veneer tie, and a veneer (outer wythe) reinforcement and is surface mounted on an externally insulated dry wall. For the first embodiment, a cavity wall having an insulative layer of 2.5 inches (approx.) and a total span of 3.5 inches (approx.) is chosen as exemplary. As the veneer being anchored is a jumbo brick veneer, the anchoring system includes extra vertical adjustment. [0072] The surface-mounted anchoring system for cavity walls is referred to generally by the numeral 10 . A cavity wall structure 12 is shown having an inner wythe or dry wall backup 14 with sheetrock or wallboard 16 mounted on metal studs or columns 17 and an outer wythe or facing wall 18 of brick 20 construction. Between the inner wythe 14 and the outer wythe 18 , a cavity 22 is formed. The cavity 22 , which has a 3.5-inch span, has attached to the exterior surface 24 of the inner wythe 14 insulation in the form of insulating panels 26 . The insulation 26 is disposed on wallboard 16 . Seams 28 between adjacent panels of insulation 26 are substantially vertical and each aligns with the center of a column 17 . [0073] Successive bed joints 30 and 32 are substantially planar and horizontally disposed and in accord with building standards are 0.375-inch (approx.) in height. Selective ones of bed joints 30 and 32 , which are formed between courses of bricks 20 , are constructed to receive therewithin the insertion portion of the anchoring system hereof. Being surface mounted onto the inner wythe, the anchoring system 10 is constructed cooperatively therewith, and as described in greater detail below, is configured to minimize air and moisture penetration around the wall anchor/inner wythe juncture. [0074] For purposes of discussion, the cavity surface 24 of the inner wythe 14 contains a horizontal line or x-axis 34 and an intersecting vertical line or y-axis 36 . A horizontal line or z-axis 38 , normal to the xy-plane, passes through the coordinate origin formed by the intersecting x- and y-axes. A two-piece wall anchor 40 is shown which has an inner or U-shaped-leg portion 42 nested therewithin. The legs penetrate the wallboard 16 insulation 26 . Two-piece wall anchor 40 is a stamped metal construct which is constructed for surface mounting on inner wythe 14 and for interconnection with veneer tie 44 . [0075] The veneer tie 44 is adapted from one shown and described in Hohmann, U.S. Pat. No. 4,875,319, which patent is incorporated herein by reference. The veneer tie 44 is shown in FIG. 1 as being emplaced on a course of bricks 20 in preparation for embedment in the mortar of bed joint 30 . In this embodiment, the system includes a veneer or outer wythe reinforcement 46 , a wall anchor 40 and a veneer tie 44 . The veneer reinforcement 46 is constructed of a wire formative conforming to the joint reinforcement requirements of ASTM Standard Specification A951-00, Table 1, see supra. [0076] At intervals along a horizontal line surface 24 , two-piece wall anchors 40 are surface-mounted using mounting hardware 48 . The two-piece wall anchors 40 are positioned on surface 24 so that the longitudinal axis of a column 17 lies within the yz-plane formed by the longitudinal axes 50 and 52 of upper leg 54 and lower leg 56 , respectively. As best shown in FIG. 2, the legs 54 and 56 are constructed so that the base surface 58 of the outer portions and the base surface 60 of the inner portion are substantially coplanar and, when installed, lie in an xy-plane. It is noted that the inner portion 42 covers the opening formed from stamping out the bail or bar 62 in the outer portion. Upon insertion of the legs 54 and 56 into insulation 26 , the base surfaces 58 and 60 suround the openings formed by the insertions. As the surfaces 58 and 60 rest snugly against the insulation, the insertion opening is covered precluding the passage of air and moisture therethrough. This construct maintains the insulation integrity. Optionally, a layer of Textroseal® sealant 63 , a thick multiply polyethylene/polymer-modified asphalt distributed by Hohmann & Barnard, Inc., Hauppauge, N.Y. 11788 may be applied under the base surfaces 58 and 60 for additional protection. [0077] The dimensional relationship between wall anchor 40 and veneer tie 44 limits the axial movement of the construct. Each veneer tie 44 has a rear leg 64 opposite the bed-joint-deposited portion thereof which is formed continuous therewith. The slot or bail aperture 66 of bail 62 is constructed, in accordance with the building code requirements, to be within the predetermined dimensions to limit the z-axis 38 movement. The slot 66 is slightly larger horizontally than the diameter of the tie. The bail-receiving slot 66 is elongated vertically to accept a veneer tie threadedly therethrough and permit y-axis adjustment. The dimensional relationship of the rear leg 64 to the width of bail 62 limits the x-axis movement of the construct. The width of the bail 62 distributes lateral forces in a manner avoiding pin-point loading. For positive interengagement and to prevent disengagement under seismic conditions, the front legs 68 and 70 of veneer tie 44 and the reinforcement wire 46 are sealed in bed joint 30 forming a closed loop. [0078] The two-piece wall anchor 40 is seen in more detail in FIGS. 2 through 4. The legs 54 and 56 are seen as being inset from the edges 72 and 74 and then extending at 90° from the inboard seams 76 and 78 , respectively, so as to extend parallel the one to the other. The legs 54 and 56 are dimensioned so that, upon installation, they extend through insulation panels 26 and wallboard 16 and the endpoints 80 thereof abut the metal studs 17 . Although only two leg structures are shown, it is within the contemplation of this invention that more two-piece legs could be constructed with each leg terminating at an inboard seam and having the insertion point 82 of the insulation 26 covered by the wall anchor body. Because the legs 54 and 56 abut the studs 17 only at endpoints 80 , the thermal conductivity across the construct is minimal as the cross sectional metal-to-metal contact area is minimized. (There is virtually no heat transfer across the mounting hardware 48 because of the nonconductive washers thereof. [0079] The description which follows is a second embodiment of the surface-mounted anchoring system for cavity walls of this invention. For ease of comprehension, wherever possible similar parts use reference designators 100 units higher than those above. Thus, the veneer tie 144 of the second embodiment is analogous to the veneer tie 44 of the first embodiment. Referring now to FIGS. 5 through 7, the second embodiment of the surface-mounted anchoring system is shown and is referred to generally by the numeral 110 . As in the first embodiment, a wall structure 112 is shown. The second embodiment has an inner wythe or backup wall 114 of a dry wall or a wallboard construct 116 on columns or studs 117 and an outer wythe or veneer 118 of facing stone 120 . Here, the anchoring system has a surface-mounted wall anchor with perforated wing portions or receptors for receiving the veneer tie portion of the anchoring system. [0080] The anchoring system 110 is surface mounted to the exterior surface 124 of the inner wythe 114 . In this embodiment batts of insulation 126 are disposed between adjacent columns 117 . Successive bed joints 130 and 132 are substantially planar and horizontally disposed and in accord with building standards are 0.375-inch (approx.) in height. Selective ones of bed joints 130 and 132 , which are formed between courses of bricks 120 , are constructed to receive therewithin the insertion portion of the anchoring system construct hereof. Being surface mounted onto the inner wythe, the anchoring system 110 is constructed cooperatively therewith, and as described in greater detail below, is configured to penetrate through the wallboard at a covered insertion point. [0081] For purposes of discussion, the cavity surface 124 of the inner wythe 114 contains a horizontal line or x-axis 134 and an intersecting vertical line or y-axis 136 . A horizontal line or z-axis 138 , normal to the xy-plane, passes through the coordinate origin formed by the intersecting x- and y-axes. A wall anchor construct 140 is shown which has a pair of legs 142 which penetrate the wallboard 116 . The wall anchor 140 is a stamped metal construct which is constructed for surface mounting on inner wythe 114 and for interconnection with veneer tie 144 . [0082] The veneer tie 144 is a box Byna-Tie® device manufactured by Hohmann & Barnard, Inc., Hauppauge, N.Y. 11788. The veneer tie 144 is shown in FIG. 5 as being emplaced on a course of bricks 120 in preparation for embedment in the mortar of bed joint 130 . In this embodiment, the system includes a wall anchor 140 and a veneer tie 144 . [0083] At intervals along a horizontal line surface 124 , wall anchors 140 are surface-mounted using mounting hardware 148 with neoprene sealing washers. The wall anchors 140 are positioned on surface 124 so that the longitudinal axis of a column 117 lies within the yz-plane formed by the longitudinal axes 150 and 152 of upper leg 154 and lower leg 156 , respectively. The legs 154 and 156 are separate L-shaped pieces, as best shown in FIG. 6, so that the base surface 158 of the leg portions and the intermediate base surface 160 are substantially coplanar and, when installed, lie in an xy-plane. Upon insertion in the wallboard 116 , the base surfaces 158 and 160 surround and rest snugly against the leg insertion openings. The surfaces 158 and 160 cover the openings precluding the passage of air and moisture therethrough and maintaining the insulation integrity. It is within the contemplation of this invention that a coating of sealant or a layer of a polymeric compound—such as a closed-cell foam—be placed on base surfaces 158 and 160 for additional sealing. [0084] In the second embodiment, perforated wing portions 162 therealong are bent upwardly (when viewing legs 142 as being bent downwardly) from intermediate base 160 for receiving veneer tie 144 therethrough. The dimensional relationship between wall anchor 140 and veneer tie 144 limits the axial movement of the construct. Each veneer tie 144 has a rear leg 164 opposite the bed-joint deposited portion thereof, which rear leg 164 is formed continuous therewith. The perforations 166 provide for selective adjustability and, unlike the other embodiments hereof, similarly restrict both the y-axis 136 and the z-axis 138 movement of the anchored veneer. The opening of the perforation 166 of wing portions 162 is constructed to be within the predetermined dimensions to limit the z-axis 138 movement in accordance with the building code requirements. The perforation 166 is slightly larger horizontally than the diameter of the tie 144 . If y-axis 136 adjustability is desired, the perforations 166 may be elongated vertically. The dimensional relationship of the rear leg 164 to the width of spacing between wing portions 162 limits the x-axis movement of the construct. Here the wingspan not only limits movement, but also avoids pin-point laoding. For positive interengagement, the front legs 168 and 170 of veneer tie 144 are sealed in bed joint 130 forming a closed loop. [0085] The wall anchor construct 140 is seen in more detail in FIGS. 6 and 7. The upper legs 154 and lower leg 156 are separate L-shaped pieces welded to recessed ends 172 and 174 , respectively, and then extending at 90° parallel the one to the other to the inboard seams 176 and 178 , respectively. The legs 154 and 156 are dimensioned so that, upon installation, they extend through wallboard 116 and the endpoints 180 thereof abut the metal studs 117 . Although only two leg structures are shown, it is within the contemplation of this invention that more legs could be constructed with each leg terminating at an inboard seam and having the insertion point 182 of the wallboard 116 covered by the wall anchor body. Because the legs 154 and 156 abut the studs 117 only at endpoints 180 , the thermal conductivity across the construct is minimal as the cross sectional metal-to-metal contact area is minimized. (There is virtually no heat transfer across the mounting hardware 148 because of the nonconductive washers thereof. [0086] The description which follows is a third embodiment of the surface-mounted anchoring system for cavity walls of this invention. For ease of comprehension, wherever possible similar parts use reference designators 100 units higher than those above. Thus, the veneer tie 244 of the third embodiment is analogous to the veneer tie 144 of the second embodiment. Referring now to FIGS. 8 through 10, the third embodiment of the surface-mounted anchoring system is shown and is referred to generally by the numeral 210 . As in the previous embodiments, a wall structure 212 is shown. Here, the third embodiment has an inner wythe or backup wall 214 of masonry block 216 and an outer wythe or veneer 218 of facing brick 220 . The anchoring system has a surface-mounted wall anchor construct with slotted wing portions or receptors for receiving the veneer tie portion of the anchoring system and a low-profile box tie. [0087] The anchoring system 210 is surface mounted to the exterior surface 224 of the inner wythe 214 . In this embodiment panels of insulation 226 are disposed on the masonry block 216 . Successive bed joints 230 and 232 are substantially planar and horizontally disposed and in accord with building standards are 0.375-inch (approx.) in height. Selective ones of bed joints 230 and 232 , which are formed between courses of bricks 220 , are constructed to receive therewithin the insertion portion of the anchoring system construct hereof. Being surface mounted onto the inner wythe, the anchoring system 210 is constructed cooperatively therewith, and as described in greater detail below, is configured to penetrate through the insulation at a covered insertion point. [0088] For purposes of discussion, the cavity surface 224 of the inner wythe 214 contains a horizontal line or x-axis 234 and an intersecting vertical line or y-axis 236 . A horizontal line or z-axis 238 , normal to the xy-plane, passes through the coordinate origin formed by the intersecting x- and y-axes. A two-piece wall anchor 240 is shown which has a pair of legs 242 which penetrate the insulation 226 . Two-piece wall anchor 240 is a stamped metal construct which is constructed for surface mounting on inner wythe 214 and for interconnection with veneer tie 244 . [0089] The veneer tie 244 is adapted from the low-profile box Byna-Tie® device manufactured by Hohmann & Barnard, Inc., Hauppauge, N.Y. 11788 under U.S. Pat. No. 6,279,283. The veneer tie 244 is shown in FIG. 8 as being emplaced on a course of bricks 220 in preparation for embedment in the mortar of bed joint 230 . In this embodiment, the system includes a two-piece wall anchor 240 and a canted veneer tie 244 . [0090] At intervals along a horizontal line surface 224 , two-piece wall anchors 240 are surface-mounted using masonry mounting hardware 248 . The two-piece wall anchors 240 are positioned on surface 224 at the intervals required by the applicable building codes. The upper leg 254 and lower leg 256 are inserted through the wall anchor body 240 , as best shown in FIG. 9, so that the base surface 258 and, when installed, lies in an xy-plane about the leg insertion openings. Upon insertion in insulation 226 , the base surface 258 rests snugly against the openings formed by the legs and serves to cover the opening precluding the passage of air and moisture therethrough, thereby maintaining the insulation integrity. It is within the contemplation of this invention that a coating of sealant or a layer of a polymeric compound—such as a closed-cell foam—be placed on base surface 258 for additional sealing. [0091] In the third embodiment, slotted wing portions 262 therealong are bent upwardly (when viewing legs 242 as extending downwardly) from base 258 for receiving veneer tie 244 therethrough. The dimensional relationship between wall anchor 240 and veneer tie 244 limits the axial movement of the construct. Each veneer tie 244 has a rear leg 264 opposite the bed-joint deposited portion thereof, which rear leg 264 is formed continuous therewith. The slots 266 provide for adjustability and, unlike the second embodiment hereof, do not restrict the y-axis 236 movement of the anchored veneer. The opening of the slot 266 of wing portions 262 is constructed to be within the predetermined dimensions to limit the z-axis 238 movement in accordance with the building code requirements. The slots 266 are slightly larger horizontally than the diameter of the tie 244 . The dimensional relationship of the rear leg 264 to the width of spacing between wing portions 262 limits the x-axis movement of the construct. For positive interengagement, the front legs 268 and 270 of veneer tie 244 are sealed in bed joint 230 forming a closed loop. [0092] The two-piece wall anchor 240 is seen in more detail in FIGS. 9 and 10. The upper leg 254 and lower leg 256 extend through slots 272 and 274 , respectively, and bend 90° at the inboard seams 276 and 280 , respectively, so as to extend parallel the one to the other. The legs 254 and 256 are dimensioned so that, upon installation, they extend through insulation panels 226 and the endpoints 280 thereof abut the exterior surface 224 of masonry block 216 . Because the insertion point 282 into insulation 226 of the legs 254 and 256 is sealingly covered by the structure, the water and water vapor penetration into the backup wall is minimal. [0093] In the veneer tie shown in FIGS. 8 and 10, a bend is made at a point of inflection 284 . This configuring of the veneer tie 244 , compensates for the additional strengthening of wall anchor 240 at crossbar 286 . Thus, if the bed joint 230 is exactly coplanar with the strengthening crossbar 286 the bent veneer tie 244 facilitates the alignment thereof. [0094] In the above description of the two-piece wall anchors of this invention various configurations are described and applications thereof in corresponding anchoring systems are provided. Because many varying and different embodiments may be made within the scope of the inventive concept herein taught, and because many modifications may be made in the embodiments herein detailed in accordance with the descriptive requirement of the law, it is to be understood that the details herein are to be interpreted as illustrative and not in a limiting sense.
Wall anchor constructs and anchoring systems employing the same are disclosed. Each anchor is a sheetmetal construct utilizable with various wire formative veneer ties. In the wall anchor structures, the junctures of the legs and the base of the wall anchor are located inboard from the periphery of the wall anchor base. With the surfaces of the leg base and the anchor base coplanar, the leg insertion point is, upon installation, sealed thereby. This sealing precludes penetration of air, moisture, and water vapor into the wall structure. Various embodiments showing wall anchor configurations with suitable veneer ties are provided.
4
[0001] The present application claims the benefit of U.S. Provisional Application Ser. No. 60/692,196, filed Jun. 17, 2005, which application is incorporated herein by reference. BACKGROUND OF THE INVENTION [0002] The present invention relates to vehicle occupant restraint and in particular to an adjustable occupant restraint allowing limited occupant movement in a moving vehicle. [0003] Numerous vehicles (land, water and air) require that passengers/crew be mobile during vehicle operation. Such mobility may cause problems for the mobile occupant if the vehicle makes a sharp turn, is involved in a crash, or encounters turbulent conditions. For the ambulance community, in particular, the accident/injury rate for occupants is one of the highest for all types of motor vehicles. Current operational procedures include being completely unrestrained to perform duties, or wearing a harness which allows the occupant to move away from the seat while still attached by straps. The issues with such procedures are that the occupant is not restrained to a substantially rigid seat, and thus is exposed to a risk of contact with hard interior components during a crash. The unrestrained occupant would continue in the direction of original vehicle travel until stopped by contact with a vehicle interior object. In the case of a harness, the occupant would swing around on the end of the straps until interior contact. All of these cases subject the occupant to a greater potential for injury than an occupant restrained to a rigid seat structure. BRIEF SUMMARY OF THE INVENTION [0004] The present invention addresses the above and other needs by providing a vehicle occupant restraint system which includes a seat base pivotally connected to a seat mounting point and seat back pivotally connecting to the seat base. The seat base pivot reside proximal to a forward edge of the seat base and the seat back pivot resides proximal to a rearward edge of the seat base. Each pivot includes a toothed rack, and an engaging member for locking the pivot. The teeth define a radius about the pivots. The engaging members are attached to the seat base and are actuated by levers attached to the seat base. A harness is attached to the seat to prevent injury of an occupant in the event of a unanticipated maneuver, crash, rough terrain, or turbulence. The restraint system comprises a robust mechanism to withstand crash loads and offer sufficient adjustment between sitting and standing positions to accommodate an occupant's duties. [0005] In accordance with one aspect of the invention, there is provided an adjustable vehicle occupant restraint system. The occupant restraint system comprises a seat mounting point, a seat base pivotally mounted to the seat mounting point proximal to a forward edge of the seat base, and a seat back pivotally mounted proximal to a rearward edge of the seat base. A seat base locking mechanism pivotally locks the seat base in one of at least two seat base positions with respect to the seat mounting point and a seat back locking mechanism pivotally locks the seat back into one of at least two seat back positions with respect to the seat base. A harness restrains the occupant with respect to the seat base and/or the seat back. A seat base lever disengages the seat base locking mechanism to permit the seat base to pivot from a first seat base position to a second seat base position, and a seat back lever disengages the seat back locking mechanism to permit the seat back to pivot from a first seat back position to a second seat back position. [0006] In accordance with another aspect of the invention, there is provided an adjustable vehicle occupant restraint system. The adjustable vehicle occupant restraint system includes a seat base pivotally mounted to a seat mounting point by a seat base pivot proximal to a forward edge of the seat base and a seat back pivotally mounted to the seat base by a seat back pivot proximal to a rearward edge of the seat base. A seat base locking mechanism locks the seat base to the seat mounting point using a seat base toothed member having angularly spaced apart first teeth and a seat base engaging member configured to engage at least one of the first teeth to lock the position of the seat base. A seat back locking mechanism locks the seat back to the seat base using a seat back toothed member having angularly spaced apart second teeth and a seat back engaging member configured to engage at least one of the second teeth to lock the position of the seat back. BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING [0007] The above and other aspects, features and advantages of the present invention will be more apparent from the following more particular description thereof, presented in conjunction with the following drawings wherein: [0008] FIG. 1 is a crew seat according to the present invention. [0009] FIG. 2A shows a seat base in a first seat base position with a seat base pivot locked. [0010] FIG. 2B shows the seat base in the first seat base position with the seat base pivot unlocked [0011] FIG. 2C shows the seat base in a second seat base position with the seat base pivot locked. [0012] FIG. 3 is a detailed view of a seat base lever showing a first slot with a third radius and a fourth radius. [0013] FIG. 4A shows a seat back in a first seat back position with a seat back pivot locked. [0014] FIG. 4B shows the seat back in the first seat back position with the seat back pivot unlocked [0015] FIG. 4C shows the seat back in a second seat back position with the seat back pivot locked. [0016] FIG. 5 is a detailed view of a seat back lever showing a second slot with a fifth radius and a sixth radius. [0017] FIG. 6A shows an occupant in the crew seat in a first seat base position and a first seat back position. [0018] FIG. 6B shows the occupant in the crew seat in a second seat base position and the first seat back position. [0019] FIG. 6C shows the occupant in the crew seat in a third seat base position and a second seat back position. [0020] Corresponding reference characters indicate corresponding components throughout the several views of the drawings. DETAILED DESCRIPTION OF THE INVENTION [0021] The following description is of the best mode presently contemplated for carrying out the invention. This description is not to be taken in a limiting sense, but is made merely for the purpose of describing one or more preferred embodiments of the invention. The scope of the invention should be determined with reference to the claims. [0022] An articulating seat 10 shown in FIG. 1 allows an occupant reasonable freedom of movement while still safely attached to a fixed seat. The seat 10 typically has a four or five point seatbelt system but could also offer some protection with a simple two-point lap belt or three-point shoulder strap lap belt restraint system. The restraint system may have extending/retractable straps that would automatically lock in a crash. Typically, the extending/retractable straps would be for the occupant's shoulders only, but this is not always the case. [0023] The seat 10 comprises a seat base 12 and a seat back 14 . The seat base 12 pivots about a seat base pivot (or hinge) 17 attached to a seat mounting point 42 (see FIG. 6A-6C ). The seat base 12 is held in position by the cooperation of a seat base engaging member (or locking pawl) 18 and a seat base toothed member 16 . The engaging member 18 is limited to linear motion by a first bracket 19 or the like. The toothed member 16 includes a plurality of angularly spaced apart teeth 16 a (see FIG. 2A ) at a common radius r 1 from the pivot 17 . The engaging member 18 fixes the rotational position of the seat base 12 by engaging at least one tooth 16 a of the toothed member 16 . The engaging member 18 may be advanced to engage the teeth by rotating a seat base lever 20 counterclockwise, wherein the engaging member 18 (see FIG. 2A ) is moved toward the toothed member 16 . The engaging member 18 may be retracted to disengage from the teeth by rotating the seat base lever 20 clockwise, wherein the engaging member 18 (see FIG. 2B ) is moved away from the toothed member 16 (see FIG. 2B ). A first spring 22 biases the engaging member 18 into the engaged (counterclockwise) position. [0024] The seat back 14 is pivotally coupled to the seat base 12 in a manner similar to the coupling of the seat base 12 to the seat mounting point 42 . A seat back engaging member (or locking pawl) 26 engages teeth 24 a (see FIG. 4A ) of a seat back toothed member 24 attached to the seat back 14 . The seat back 14 pivots about a seat back (or second) pivot (or hinge) 25 attached to the seat base 12 . The toothed member 24 includes a plurality of angularly spaced apart teeth 24 a at a common radius r 2 from the pivot 25 . The engaging member 26 is limited to linear motion by a second bracket 27 or the like. The seat back engaging member 26 may be advanced to engage the teeth 24 a by rotating a seat back lever 28 counterclockwise, wherein the engaging member 26 is moved toward the toothed member 24 . The engaging member 26 may be retracted to disengage from the teeth 26 a by rotating a seat back lever 28 clockwise, wherein the engaging member 26 is moved away from the toothed member 24 . A second spring 30 biases the engaging member 26 into the engaged position. [0025] A detailed view of the seat base 12 in a first seat bottom position, and with the engaging member 18 engaging the toothed member 16 , is shown in FIG. 2A . The lever 20 is in a counterclockwise position as indicated by a first arc 32 . A slot 34 (see FIG. 3 ) in the lever 20 has a lower slot end 34 a at a third and greater radius r 3 from a seat base lever pivot point 20 a and a higher slot end 34 b at a fourth and lesser radius r 4 from the seat base lever pivot point 20 a . The engaging member 18 is biased along arrow 36 into engagement with the toothed member 16 by the cooperation of the engaging member 18 with the slot 34 in the lever 20 . Thus, when the lever 20 is in the counterclockwise position, the engaging member 18 is pushed to the right, and engages the toothed member 16 . [0026] A detailed view of the engaging member 18 disengaged from the toothed member 16 with the seat base 12 remaining in the first seat position is shown in FIG. 2B . The lever 20 is in a clockwise position as indicated by a second arc 38 . The engaging member 18 is pulled along arrow 40 into disengagement from the toothed member 16 by the cooperation of the engaging member 18 with the slot 34 in the lever 20 . As the lever 20 moves to the clockwise position the slot end of the engaging lever 18 follows the slot to the higher slot end 34 b and is pulled towards the seat base lever pivot point 20 a and away from the toothed member 16 . [0027] A detailed view of the seat base 12 in a second seat base position (a raised position) with the engaging member 18 engaging the toothed member 16 , is shown in FIG. 2C . The lever 20 is in a counterclockwise position as indicated by the arc 32 . The engaging member 18 is pushed along arrow 36 into engagement with the toothed member 16 by the cooperation of the engaging member 18 with the slot 34 in the lever 20 . The seat base 12 may further be locked into one of a multiplicity of intermediate seat base positions by engaging the engaging member 18 with an intermediate tooth of the toothed member 16 . [0028] A detailed view of the lever 20 is shown in FIG. 3 . The slot 34 has a lower end 34 a at a third radius r 3 from the pivot point 20 a , and the slot 34 has a higher end 34 b at a fourth radius r 4 from the pivot point 20 a . The radius r 3 is greater than the radius r 4 . The difference between radius r 3 and radius r 4 results in a translation of the engaging member 18 when the lever 34 is rotated about the pivot point 20 a , which translation is sufficient to disengage the engaging member 18 from the toothed member 16 . [0029] A detailed view of the seat back 14 in a first seat back position, and with the engaging member 24 engaging the toothed member 24 , is shown in FIG. 4A . The lever 28 is in a counterclockwise position as indicated by a fourth arc 29 . A slot 35 (see FIG. 5 ) in the lever 28 has a upper slot end 35 a at a fifth and greater radius r 5 from a seat back lever pivot 28 a (which may coincide with the pivot point 20 a ) and a lower slot end 35 b at a sixth and lesser radius r 6 from the seat back lever pivot point 28 a . The engaging member 26 is biased along arrow 46 into engagement with the toothed member 24 by the cooperation of the engaging member 26 with the slot 35 in the lever 28 . Thus, when the lever 28 is in the counterclockwise position, the engaging member 26 is pushed to the left, and engages the toothed member 24 . [0030] A detailed view of the engaging member 26 disengaged from the toothed member 24 with the seat back 14 remaining in the first seat back position is shown in FIG. 4B . The lever 28 is in a clockwise position as indicated by a second arc 31 . The engaging member 26 is pulled along arrow 48 into disengagement from the toothed member 24 by the cooperation of the engaging member 26 with the slot 35 in the lever 28 . As the lever 28 moves to the clockwise position, the slot end of the engaging lever 26 follows the slot 35 to the lower slot end 35 b and is pulled towards the lever pivot point 28 a and away from the toothed member 24 . [0031] A detailed view of the seat back 14 in a second seat back position (a straightened position) with the engaging member 26 engaging the toothed member 24 , is shown in FIG. 4C . The lever 28 is in a counterclockwise position as indicated by the arc 29 . The engaging member 26 is pushed along arrow 46 into engagement with the toothed member 24 by the cooperation of the engaging member 26 with the slot 35 in the lever 28 . [0032] A detailed view of the lever 28 is shown in FIG. 5 . The slot 33 has a lower end 35 b at a fifth radius r 5 from the pivot point 28 a , and the slot 35 has a lower end 35 b at a sixth radius r 6 from the pivot point 28 a . The radius r 5 is greater than the radius r 6 . The difference between radius r 5 and radius r 6 results in a translation of the engaging member 26 when the lever 35 is rotated about the pivot point 28 a , which translation is sufficient to disengage the engaging member 26 from the toothed member 24 . [0033] A seat occupant 44 is shown in a fully seated position in FIG. 6A , in a partially seated position in FIG. 6B , and in a standing position in FIG. 6C . The seat 10 position in FIG. 6A corresponds to the seat base 12 being in the first seat base position and the seat back 14 being in the first seat back position. The partially seated position in FIG. 6B corresponds to the seat base 12 being in an intermediate seat position and the seat back 14 remaining in the first seat back position, wherein the seat base 12 has pivoted about a point proximal to a seat base forward edge 12 a . The standing position in FIG. 6C corresponds to the seat base being in the second seat base position and the seat back being in a second seat back position, wherein the seat back 14 has pivoted about a point proximal to a seat base rearward edge 12 b. [0034] While the invention herein disclosed has been described by means of specific embodiments and applications thereof, numerous modifications and variations could be made thereto by those skilled in the art without departing from the scope of the invention set forth in the claims.
A vehicle occupant restraint system includes a seat base pivotally connected to a seat mounting point and seat back pivotally connecting to the seat base. The seat base pivot reside proximal to a forward edge of the seat base and the seat back pivot resides proximal to a rearward edge of the seat base. Each pivot includes a toothed rack, and an engaging member for locking the pivot. The teeth define a radius about the pivots. The engaging members are attached to the seat base and are actuated by levers attached to the seat base. A harness is attached to the seat to prevent injury of an occupant in the event of a unanticipated maneuver, crash, rough terrain, or turbulence. The restraint system comprises a robust mechanism to withstand crash loads and offer sufficient adjustment between sitting and standing positions to accommodate an occupant's duties.
1
RELATED APPLICATION This application is a continuation-in-part of Ser. No. 912,384 filed Jul. 13, 1992 now abandoned. BACKGROUND OF THE INVENTION Antiviral agents having a guaninyl substituent on a carbohydrate surrogate are known. For example, the compound 1R-(1α,2β,3α)!-2-amino-9- 2,3-bis (hydroxymethyl)cyclobutyl!-1,9-dihydro-6H-purin-6-one, i.e., ##STR4## is an antiviral agent with activity against herpes simplex virus type 1 and 2, varicella zoster virus, human cytomeglavirus, vaccina virus, murine leukemia virus, and human immunodeficiency virus. Bisacchi et al. in U.S. Pat. No. 5,064,961 disclose preparing this antiviral agent by reacting a bis(2,3-protected hydroxymethyl)cyclobutane of the formula ##STR5## wherein X is a leaving group and R 4 is a protecting group with a protected guanine such as 2-amino-6-benzyloxypurine, 2-amino-6-methoxyethoxypurine, 2-amino-6-chloropurine, or 2-acetamido-6-hydroxy-purine in the presence of a base such as potassium carbonate or sodium hydride in a solvent such as dimethylformamide at from about 40° C. to 150° C., preferably 100° to 120° C. for 4 to 48 hours. Removal of the R 4 protecting groups and the guanine protecting group yields the desired antiviral agent. Slusarchyk et al. in U.S. Pat. No. 5,126,345 disclose a similar process to prepare the racemic compound (±)-(1α,2β,3α)-2-amino-9- 2,3-bis(hydroxy-methyl)cyclobutyl!-1,9-dihydro-6H-purin-6-one. Ichikawa et al. in European Patent Application 358,154 disclose reacting a cyclobutane of the formula ##STR6## wherein X is a leaving group and R 4 is hydrogen or a protecting group with a nucleic acid base including 2-amino-6-chloropurine in the presence of a basic catalyst. Ichikawa disclose the preparation of 1R-(1α,2β,3α)!-2-amino-9- 2,3-bis(hydroxymethyl)-cyclobutyl!-1,9-dihydro-6H-purin-6-one. Norbeck et al. in U.S. Pat. No. 5,153,352 also disclose the preparation of 1R-(1α,2β,3α)!-2-amino-9- 2,3-bis(hydroxymethyl)-cyclobutyl!-1,9-dihydro-6H-purin-6-one. Hagberg et al. in European Patent Application 55,239 and Zahler et al. in European Patent Application 458,363 disclose the tetrabutylammonium salt of 2-amino-6-benzyloxypurine. SUMMARY OF THE INVENTION This invention is directed to a process for preparing antiviral compounds of the formula ##STR7## wherein Z is a carbohydrate surrogate by reacting a purine salt of the formula ##STR8## with the compound of the formula (III) Z.sub.1 --X to yield the purine of the formula ##STR9## wherein X is a leaving group, Z 1 is a protected form of carbohydrate surrogate Z, Y 1 is iodo, bromo, or chloro, and R 1 , R 2 , R 3 , and R 4 are independently straight or branched chain alkyl of 1 to 10 carbons or substituted straight or branched chain alkyl of 1 to 10 carbons. The compound of formula IV is then converted to the antiviral agent of formula I. In the preferred process of this invention, the antiviral agent of formula I is 1R-(1α,2β,3α)!-2-amino-9- 2,3-bis(hydroxymethyl)cyclobutyl!-1,9-dihydro-6H-purin-6-one and it is prepared by reacting a purine salt of formula II with the bis(2,3-protected hydroxymethyl) cyclobutane of the formula ##STR10## wherein Prot is a hydroxy protecting group. This reaction yields the cyclobutyl purine of the formula ##STR11## which is then converted to the antiviral agent 1R-(1α,2β,3α)!-2-amino-9- 2,3-bis(hydroxymethyl)-cyclobutyl!-1,9-dihydro-6H-purin-6-one. The bis(2,3-protected hydroxymethyl)-cyclobutane of formula V is optically active, the relative sterochemistry of the substituent x is drawn to indicate that the leaving group X is cis to the vicinal --CH 2 --O--Prot substituent and that the two --CH 2 --O--Prot substituents are trans to each other. This invention is also directed to the novel purine salts of formula I. DETAILED DESCRIPTION OF THE INVENTION The term "alkyll" refers to straight and branched chain groups of 1 to 10 carbons. The term "substituted alkyl" refers to such alkyl groups of 1 to 10 carbons having one, two or three substituents, preferably one, selected from alkoxy of 1 to 6 carbons and aryl. The term "aryl" refers to phenyl and phenyl having one, two, or three substituents, preferably one, selected from alkyl of 1 to 6 carbons, alkoxy of 1 to 6 carbons, chloro, bromo, iodo, and fluoro. The carbohydrate surrogate Z includes cyclized and acyclic moieties which possess antiviral activity when substituted with a guanine moiety. Suitable groups for Z include ##STR12## Z 1 represents the moiety Z wherein the hydroxy groups are protected. Suitable hydroxy protecting groups include hindered silyl groups such as t-butyl-dimethylsilyl, t-butyldiphenylsilyl, (triphenyl-methyl)dimethylsilyl, methyldiisopropylsilyl and triisopropylsilyl, benzyl and substituted benzyl groups such as p-methoxybenzyl, acyl groups of the formula ##STR13## wherein R 5 is a straight or branched chain lower alkyl of 1 to 6 carbons, or phenyl, especially acetyl or benzoyl, trityl, and substituted trityl groups such as 4-monomethoxy trityl or 4,4'-dimethoxytrityl. X in the compounds of formula III is a leaving group such as chloro, bromo, iodo, an aryl sulfonyloxy group such as p-toluenesulfonyloxy, an alkyl sulfonyloxy group such as methanesulfonyloxy, a substituted alkyl sulfonyloxy group, preferably a perfluoroalkanesulfonyloxy group such as trifluoromethanesulfonyloxy, a nitro-substituted benzene sulfonyloxy group such as p-nitro-benzenesulfonyloxy, or fluorosulfonyloxy. The compounds of formula III are prepared according to known procedures or as set forth below. For example, the bis(2,3-protected hydroxymethyl)-cyclobutane of formula V can be prepared as taught by Bisacchi et al. in U.S. Pat. No. 5,064,961. For example, when X is a perfluoroalkane sulfonyloxy group such as trifluoromethanesulfonyloxy, the perfluoroalkanesulfonic anhydride such as trifluoromethanesulfonic anhydride is reacted with the diprotected 2,3- hydroxymethyl cyclobutanol of the formula ##STR14## in an inert solvent such as methylene chloride or chloroform, preferably methylene chloride, in the presence of a base such as pyridine or triethylamine, preferably pyridine. The reaction can be run at from about -20° C. to the boiling point of the solvent, preferably at about 0° C. to room temperature. When X is a nitro-substituted benzene sulfonyloxy group such as p-nitrobenzenesulfonyloxy, the cyclobutanol of formula VII is reacted with a nitro-substituted benzene sulfonating reagent such as p-nitrobenzenesulfonyl chloride in pyridine or in an inert solvent such as methylene chloride or chloroform containing a base such as pyridine or triethylamine. When X is fluorosulfonyloxy, the cyclobutanol of formula VII is reacted with fluorosulfonic anhydride in pyridine or in an inert solvent such as methylene chloride or chloroform containing a base such as pyridine or triethylamine. The compounds of formula III ##STR15## can be prepared from the pyran of the formulas ##STR16## For example, treatment of the compound of formula VIII with p-toluenesulfonyl chloride in pyridine, or methanesulfonyl chloride and triethylamine, or trifluoromethanesulfonic anhydride and pyridine affords the corresponding compounds of formula III wherein X is p-toluenesulfonyloxy, methane-sulfonyloxy, or trifluoromethanesulfonyloxy, respectively. Alternatively, these compounds of formula III wherein X is p-toluenesulfonyloxy can also be prepared from the isomeric compound of formula IX by known methods see I. Galynker et al., Tetrahedron Letters, 23, 4461(1982)!. For example, treatment of compound IX with diethyl or diisopropyl azodi-carboxylate in the presence of triphenylphosine, and zinc p-toluenesulfonate affords the compound of formula III wherein X is p-toluenesulfonyloxy. Alternatively, these compounds of formula III wherein X is p-toluenesulfonyloxy or methanesulfonyloxy can also be prepared from the compound of formula IX by treatment with p-toluenesulfonic acid or methane-sulfonic acid, respectively, in the presence of triethylamine, triphenylphosine, and diethyl or diisopropyl azodicarboxylate in a solvent such as toluene, ether, or dioxane. These compounds of formula III wherein X is chloro, bromo, or iodo can be prepared by treating a compound of formula IX with a methyltriphenoxy-phosphonium halide or methyltriphenylphosphonium halide (i.e., chloride, bromide, or iodide) in a solvent such as dimethylformamide. Alternatively, these compounds of formula III wherein X is chloro, bromo, or iodo can be prepared from the compound of formula IX using triphenylphosphine, diethyl or diisopropyl azodicarboxylate, and a source of halide such as methyl iodide, methyl bromide, or methylene chloride according to methodology known in the art. See, for example, H. Loibner et al., Helv. Chim. Acta., 59, 2100 (1976). The compounds of formulas VIII and IX can be prepared from the known compound of formula X See M. Okabe et al., Tetrahedron Letters, 30, 2203 (1989); M. Kugelman et al., J. Chem. Soc. Perkin I, 1113 (1976); B. Fraser-Reid et al., J. Amer. Chem. Soc., 92, 6661(1970) for the preparation of the compound of formula X! as outlined below: ##STR17## Treatment of the compound of formula X with various hydroxyl protecting reagents known in the art affords the compounds of formula XI. The compound of formula XI wherein the hydroxy protecting groups are acetyl can also be obtained by the direct reduction of tri-O-acetyl-D-glucal, i.e. ##STR18## see N. Greenspoon et al., J. Org. Chem., 53, 3723 (1988). Alternatively, this compound of formula XI can also be obtained by treatment of tri-O-acetyl-D-glucal with sodium borohydride in the presence of Cu(I)Br and tetrakis(triphenylphosphine)-palladium(O) in an aprotic solvent such as tetrahydrofuran and/or dimethoxyethane. Hydroboration of the compound of formula XI with borane-tetrahydrofuran complex followed by treatment with aqueous sodium bicarbonate and 30% hydrogen peroxide affords a mixture of the compound of formula VIII and the isomeric compound of formula IX which can be separated, e.g., by chromatography on silica gel. The compounds of formula III ##STR19## are taught by Zahler et al. in European Patent Application 458,363. The compounds of formula III ##STR20## are taught by Slusarchyk in European Application 352,013. The compounds of formula III ##STR21## are taught by Zahler et al. in U.S. Pat. No. 5,059,690. The compounds of formula III ##STR22## are taught by Ravenscroft in U.S. Pat. No. 4,658,044. The compounds of formula III ##STR23## are taught by Borthwick et al., J. Chem. Soc. Chem. Commun., 1988, p. 656-658. The compounds of formula III ##STR24## are taught by Hanna et al., J. Heterocyclic Chem., Vol. 25, p. 1899-1903 (1988). Similarly, the acyclic compounds of formula III are taught in the literature as note Martin et al., Nucleosides & Nucleotides, Vol. 8, p. 923-926 (1989); Bronson et al., J. Med. Chem., Vol. 32., p. 1457-1463 (1989); Harden et al., J. Med. Chem., Vol. 30, p 1636-1642 (1987) and J. Med. Chem., Vol. 32, p. 1738-1743 (1989); and Kim et al., J. Med. Chem., Vol. 33, p. 1207-1213 (1990) and J. Med. Chem., Vol. 33, p. 1797-1800 (1990). The purine salts of formula II are prepared by reaction of a purine compound of the formula ##STR25## with a compound of the formula ##STR26## in a solvent such as ethanol or methylene chloride and water followed by isolation of the salt from the reaction. The purine compound of formula XII wherein Y 1 is chloro is commercially available or can be prepared by known methods. The purine of formula XII wherein Y 1 is bromo can be prepared by the procedure described by A. G. Beamon et al., J. Org. Chem., 27, 986 (1962). The compound of formula XII wherein Y 1 is iodo can be prepared by treatment of the compound of formula XII wherein Y 1 is chloro with aqueous hydroiodic acid at about 1° C. The compounds of formula XIII are known in the art and are either commercially available or can be prepared by published methods. The reaction between the purine salt of formula II and the compound of formula III is run in an aprotic solvent such as methylene chloride, acetonitrile, acetone, tetrahydrofuran, and the like at a temperature of from about -20° to 100° C. for from about 30 minutes to about 24 hours, preferably from about one hour to about 12 hours. When X is a perfluoroalkanesulfonyloxy group such as trifluoro-methylsulfonyloxy, the solvent employed is pre-ferably methylene chloride and the reaction is run at from about 0° C. to about 30° C. When X is a nitro-substituted benzenesulfonyloxy group such as p-nitrobenzenesulfonyloxy, the solvent employed is preferably acetonitrile and the reaction is run at from about 30° C. to about 90° C. The resulting intermediate of formula IV is converted to the desired antiviral agent of formula I by selective removal of the hydroxy protecting group or groups in Z 1 and conversion of the Y 1 group to a 6-oxo. For example, when the hydroxy protecting group or groups in the compound of formula IV are acyl treatment with catalytic sodium methoxide in methanol yields the compound of the formula ##STR27## Similarly, when the hydroxy protecting group or groups in the compound of formula IV are hindered silyl groups treatment with fluoride ion such as tetrabutylammonium fluoride yields the compound of formula XIV and when the hydroxy protecting group or groups in the compound of formula IV are benzyl or substituted benzyl treatment with boron trichloride yields the compound of formula XIV. Acid hydrolysis of the compound of formula XIV such as by using hot aqueous hydrochloric acid gives the desired 6-oxo antiviral agent of formula I. Alternatively, treatment of the compound of formula IV wherein the hydroxy protecting group or groups are acyl, benzyl, or substituted benzyl with hot aqueous acid effects selective conversion of the Y 1 group to a 6-oxo group to provide a compound of the formula ##STR28## wherein the hydroxy group or groups in Z 1 are protected by an acyl, benzyl, or substituted benzyl. In this reaction, when the protecting group or groups are acyl and Y 1 is iodo treatment of the compound of formula IV with hot aqueous acetic acid yields the compound of formula XV. When the hydroxy protecting group or groups are benzyl or substituted benzyl and Y 1 is chloro, bromo or iodo treatment of the compound of formula IV with hot aqueous hydrochloric acid yields the compound of formula XV. The hydroxy protecting group or groups can then be removed from the compound of formula XV by the methods described above or other known methods in the art to give the desired antiviral agents of formula I. For example, when the hydroxy protecting group or groups are an acyl such as benzoyl treatment with aqueous sodium hydroxide or sodium methoxide in methanol will give the desired final product. Similarly, when the hydroxy protecting group or groups is benzyl or substituted benzyl hydrogenolysis will give the desired product. In a further alternate procedure, the compound of formula XIV or the hydroxy protected compound of formula IV wherein the protecting group or groups are acyl can be treated with excess sodium methoxide in methanol at reflux to provide a compound of the formula ##STR29## Acid hydrolysis, for example, using hot aqueous hydrochloric acid, of the compound of formula XVI gives the desired 6-oxo antiviral agent of formula I. Alternatively, treatment of a compound of formula IV wherein the hydroxy protecting group or groups are acyl with hot aqueous hydroxide such as sodium or potassium hydroxide or with an acid such as hydrochloric acid followed by sodium or potassium hydroxide and heating gives the desired 6-oxo antiviral agent of formula I. Preferably, the process of this invention employs the compounds of formula III wherein Z 1 --X is ##STR30## Prot is acetyl or benzoyl. X is p-nitrobenzenesulfonyloxy or trifluoromethanesulfonyloxy. Preferred purine salts of formula I for use within the process of this invention are those wherein: Y 1 is chloro or iodo, especially iodo. R 1 , R 2 , R 3 and R 4 are each n-butyl or R 1 , R 2 , and R 3 are ethyl and R 4 is benzyl. This preferred process, particularly when Z 1 --X is ##STR31## can be performed under milder reaction conditions, in a shorter period of time, and with higher yields than previously reported process for preparing the antiviral agents of formula I. The following examples are illustrative of the invention. EXAMPLE 1 1R-(1α,2β,3α)!-2-Amino-9- 2,3-bis(hydroxymethyl)-cyclobutyl!-1,9-dihydro-6H-purin-6-one a) 6-Iodo-9H-purin-2-amine 6-Chloro-9H-purin-2-amine (5.0 g., 29.5 mmole) was added to 47% hydrogen iodide (61 ml., 12.2 ml./g.) chilled in an ice bath. After 1.5 hours, water (61 ml.) was added and the mixture stirred in an ice- bath for 30 minutes. The yellow solid was filtered out and the filter cake was washed with water. The wet solid was transferred to a beaker and the residue in the funnel was washed into the beaker with water (30 ml.). 6M Sodium hydroxide (7 ml.) was added with stirring until all the solid had dissolved (pH 14). The solution was added to boiling water (30 ml.) containing acetic acid (3 ml.). The mixture was boiled briefly and allowed to stand at room temperature for one hour. The product was filtered off, washed with water, and dried under vacuum overnight to give 6.88 g. of the desired product; m.p. about 240° C. (dec.). Anal. calc'd. for C 5 H 4 N 5 I 0.014 H 2 O: C, 22.99; H, 1.55; N, 26.81; I, 48.57; H 2 O, 0.10 Found: C, 23.32; H, 1.52; N, 26.75; I, 48.14; H 2 O, 0.09. b) 6-Iodo-9H-purin-2-amine, ion (1-), triethyl-(phenylmethyl) ammonium(1:1) salt Benzyltriethylammonium hydroxide (24.6 ml., 43.3 mmole, 40 wt % in methanol) was added to a suspension of 6-iodo-9H-purin-2-amine (10.0 g., 38.3 mmole) stirred in absolute ethanol (22 ml.) until nearly all of the suspension had dissolved. Additional 6-iodo-9H-purin-2-amine (0.4 g.) was added and the mixture was stirred for 15 minutes. The excess 6-iodo-9H-purin-2-amine was filtered off, washed with absolute ethanol, and the filtrate evaporated until no more ethanol was observed on the condenser. The residue was rapidly stirred while ethyl acetate (25 ml.) was added all at once. A solution was formed from which a solid precipitated. Additional ethyl acetate (175 ml.) was added dropwise over 30 minutes. After precipitation was complete, the mixture was stirred for 2 hours, filtered, washed with ethyl acetate, and dried under vacuum to give 15.16 g. of the desired salt product; m.p. 156°-159° C. (effervescent). Anal. calc'd. for C 18 H 25 N 5 I.0.065 H 2 O.0.02 starting material: C, 47.39; H, 5.54; N, 18.63; I, 28.22; H 2 O, 0.26 Found: C, 47.45; H, 5.50; N, 18.89; I, 27.94; H 2 O , 0.26. c) 1S-(1α,2β,3α)!-3-(2-Amino-6-iodo-9H-Durin-9-yl)-1.2-cyclobutanedimethanol, dibenzoate ester Trifluoromethanesulfonic anhydride (4.02 ml., 24.0 mmole) in dry methylene chloride (4 ml.) was added dropwise over 5 minutes to a solution of 1S-(1α,2β,3β)!-3-hydroxy-1,2-cyclobutane-dimethanol, dibenzoate ester (6.80 g., 20.0 mmole) and pyridine (2.56 ml., 30.0 mmole) in methylene chloride (30 ml.) chilled in an ice-bath. After 20 minutes, the reaction was quenched with ice, washed into a separatory funnel with methylene chloride, and washed with cold water (2×30 ml.), 5% sodium bisulfate (30 ml.), and water (30 ml.). Each aqueous layer was rinsed with a few mls. of methylene chloride which were added to the previous layer. The methylene chloride layer was dried with magnesium sulfate with stirring for 5 minutes. The mixture was filtered and the magnesium sulfate was washed three times with methylene chloride. The total volume of the methylene chloride filtrate was about 75 ml. (about 0.25M in trifluoromethane-sulfonate). 6-Iodo-9H-purin-2-amine, ion (1 - ), triethyl-(phenylmethyl) ammonium (1:1) salt (10.49 g., 22.0 mmole) was added and the suspension was stirred at room temperature. After 6 hours the mixture was filtered, the filter cake was washed with methylene chloride, and the filtrate evaporated. The residue was taken up in water (50 ml.) and ethyl acetate (100 ml.). The aqueous layer was separated, and the ethyl acetate layer was washed with water (3×50 ml.), 30% phosphoric acid (2×10 ml.), water (50 ml.), a mixture of 5% aqueous sodium bicarbonate (30 ml.) and brine (20 ml.), and brine (10 ml.). The organic layer was dried over magnesium sulfate for 5 minutes and 10 g. of charcoal (Dacro, fine mesh) was added. The mixture was stirred for 15 minutes, filtered through Celite, and the filter cake was washed 5 times with ethyl acetate. The filtrate was evaporated to a foam (11.67 g.). The residue was evaporated from a mixture of methylene chloride (10 ml.) and absolute ethanol (10 ml.) to form a solid. This solid was heated on the steam bath to boiling with absolute ethanol (80 ml., 7 ml. g. foam) for 2 minutes. The mixture was kept at room temperature for 3 hours, filtered, and washed twice with cold 95% ethanol. The solid was dried under vacuum overnight to give 8.07 g. of the desired product; m.p. 148°-149° C., α! D =-20.5° (c=1, chloroform). TLC (silica gel, ethyl acetate, R f =0.65). Anal. calc'd. for C 25 H 22 IN 5 O 4 .0.06 H 2 O.0.02 C 2 H 5 OH: C, 51.38; H, 3.83; N, 11.96; I, 21.68; H 2 O, 0.18 Found: C, 51.19; H, 3.77; N, 11.89; I, 21.86; H 2 O, 0.18. d) 1R-(1α,2β,3α)!-2-Amino-9- 2,3-bis(hydroxy-methyl) cyclobutyl!-1,9-dihydro-6H-purin-6-one A solution of sodium methoxide (5.3 ml., 3.9M prepared from sodium/methanol) was added by syringe to a suspension of 1S-(1α,2β,3α)!-3-(2-amino-6-iodo-9H-purin-9-yl)-1,2-cyclobutanedimethanol, dibenzoate ester (8.0 g., 13.7 mmole) in dry methanol (40 ml.). The mixture was refluxed for 1.5 hours. The solution was neutralized with 1N HCl (10.1 ml.) to pH 7. The methanol was evaporated to give a reaction mixture containing 1S-(1α,2β,3α)!-3-(2-amino-6-methoxy-9H-purin-9-yl)-1,2-cyclobutanedimethanol. This aqueous mixture was washed into a separatory funnel with water (2×8 ml.) and acidified with concentrated HCl (3.6 ml., 43.9 mmole) to pH of about 0.5. The mixture was washed with methylene chloride (3×15 ml.) to remove methylbenzoate and the aqueous layer was rotary evaporated for a few minutes to remove any residual methylene chloride. The aqueous layer was heated in a 95° oil bath for 3 hours. Sodium hydroxide (10.6 ml., 4N) was added to adjust the pH to 7. Crystals formed immediately. The mixture was allowed to cool to room temperature slowly. After standing overnight at room temperature, the mixture was chilled at 0° C. for one hour, filtered, and washed with cold water. The wet product was washed into a 250 ml. flask with 35 ml. of water. The mixture was heated to boiling and 30 ml. of water was added to dissolve all of the product. The solution was kept at room temperature for 3 hours and at 0° C. for one hour. The crystals were filtered, washed with cold water, and dried under vacuum over phosphorus pentoxide to give 3.4 g. of the desired product; m.p. about 290° C. (dec.), α! D =-24.4° (c=1, dimethylsulfoxide), +25.3° (c=1, 0.1N sodium hydroxide). TLC (silica gel; tetrahydrofuran, methanol, ammonium hydroxide, 6:3:1, R f =0.45). Anal. calc'd. for C 11 H 15 N 5 O 3 .1.04 H 2 O: C, 46.51; H, 6.06; N, 24.65; H 2 O, 6.60 Found: C, 46.71; H, 6.02; N, 24.88; H 2 O, 6.62. EXAMPLE 2 1S-(1α,2β,3α)!-3-(2-Amino-6-iodo-9H-purin-9-yl)-1,2-cyclobutanedimethanol, dibenzoate ester a) 6-Iodo-9H-purin-2-amine, ion (1-), tetrabutylammonium (1:1) salt 6-Iodo-9H-purin-2-amine (133 g., 510 mmole) ground up in a mortar and pestle was washed into a 2 liter pot with 1.5 liter dichloromethane. Aqueous tetrabutylammonium hydroxide (1.53M, 333 ml., 510 mmole) was added and the mixture was stirred mechanically for 30 minutes. The mixture was then filtered through Celite, washed five times with methylene chloride, and the methylene chloride layer was separated, dried (MgSO 4 ), and evaporated. The residue was evaporated from toluene (300 ml.). The residue was taken up in 1 liter of ethyl acetate and heated briefly to form a two-phase mixture. This mixture was stirred mechanically at room temperature for 30 minutes. The resulting crystals were filtered, washed with ethyl acetate, and dried under vacuum overnight to give 213.5 g. of product. 20 g. of this material was dried further overnight at 50° C. under vacuum over phosphorus pentoxide to give 6-iodo-9H-purin-2-amine, ion (1 - ), tetrabutylammonium (1:1) salt; m.p. 114°-116° C. Anal. Calc'd. for C 5 H 3 IN 5 .C 16 H 36 N.0.13 H 2 O: C, 49.96; H, 7.84; N, 16.65; I, 25.14; H 2 , 0.46 Found: C, 50.17; H, 7.91; N, 16.86; I, 25.33; H 2 0, 0.48. b) 1S-(1α,2β,3α)!-3-(2-Amino-6-iodo-9H-purin-9-vl)-1,2-cyclobutanedimethanol, dibenzoate ester 1S-(1α,2β,3α)!-3-Hydroxy-1,2-cyclobutane-dimethanol, dibenzoate ester (3.40 g., 10.0 mmole) was dissolved in methylene chloride (15 ml.) and chilled in an ice bath. Pyridine (1.28 ml., 15.0 mmole) was added. Trifluoromethanesulfonic anhydride (2.01 ml., 12.0 mmole) was added by syringe to methylene chloride (3 ml.) in a dropping funnel. The trifluoromethanesulfonic anhydride solution was added dropwise to the cold reaction mixture over 5 minutes. After a total of 25 minutes, the reaction was worked up at a temperature below 20° C. The reaction mixture was quenched with ice and diluted to 100 ml. with methylene chloride. The organic layer was washed with 25 ml. of each of ice-water (twice), cold 5% sodium bisulfate, and ice water. Each organic layer was backwashed with 2 ml. of methylene chloride. The combined organic layers were dried over magnesium sulfate. After filtration, the solution was evaporated down to a mobile oil in a bath of ice water. 6-Iodo-9H-purin-2-amine, ion (1 - ), tetra-butylammonium (1:1) salt (6.02 g., 12 mmole, dried over phosphorus pentoxide under vacuum at 50° C., 0.13M % water) was dissolved in methylene chloride (7 ml.) and chilled in an ice bath. The above trifluoromethanesulfonyloxy material was washed into this solution with methylene chloride (5×1 ml.). After 30 minutes, the ice bath was removed and the reaction mixture was stirred overnight at room temperature. A precipitate formed. The methylene chloride was evaporated and the residue was taken up in ethyl acetate (50 ml.) by brief heating on a steam bath. The mixture was diluted with toluene (50 ml.), washed with 30% phosphoric acid (25 and 10 ml.), and water (6×150 ml.). The organic layer was then washed with 5% sodium bicarbonate (50 ml.) and brine (50 ml.) and then dried (magnesium sulfate). Charcoal (Darco, 5 g.) was added to the dry solution, stirred for 30 minutes, and filtered through Celite. The filter cake was washed with ethyl acetate (5×10 ml.). The filtrate was evaporated to give 5.51 g. of crude product. The residue was heated to boiling with absolute ethanol (90 ml.) on the steam bath. The product formed an oil on heating which crystallized in the boiling mixture. The hot mixture was allowed to cool to room temperature and allowed to stand for 4 hours and then kept at 0° C. overnight. The crystals were filtered, washed with cold 95% ethanol (2×20 ml.), and dried under vacuum to give 4.43 g. of material, m.p. 148°-149° C. This material (1.0 g.) was dissolved in methylene chloride (3 ml.) and diluted with absolute ethanol (10 ml.). The solution was evaporated under vacuum until it had become cloudy. It was heated briefly on the steam bath and kept at room temperature for 2 hours. After being kept at 0° C. overnight, the product was filtered, washed twice with cold 95% ethanol, and dried under vacuum to give 0.946 g. of the desired product; m.p. 149°-150° C., α! D =-20.5° (c=1, chloroform). TLC (silica gel; ethanol, R f =0.59). Anal. calc'd. for C 25 H 22 IN 5 O 4 .0.13 H 2 O.0.15 C 2 H 5 OH: C, 51.28; H, 3.94; N, 11.82; I, 21.41; H 2 O, 0.4 Found: C, 51.46; H, 3.75; N, 11.76; I, 21.09; H 2 O, 0.4. EXAMPLE 3 1S-(1α,2β,3α)!-3-(2-Amino-6-methoxy-9H-purin-9-yl)-1,2-cyclobutanedimethanol An analytically pure sample of this intermediate was prepared as follows. A suspension of 1S-(1α,2β,3α)!-3-(2-amino-6-iodo-9H-purin-9-yl)-1,2-cyclobutanedimethanol, dibenzoate ester (2.915 g., 5 mmole) and sodium methoxide (0.35 ml., 4.63M in methanol, 1.62 mmole) in methanol (20 ml.) was stirred under nitrogen at room temperature. After 3.5 hours a clear solution was obtained. After 4.5 hours, sodium methoxide (1.5 ml., 4.63M in methanol, 6.9 mmole) was added and the mixture was heated at 65° C. for 5 hours. The mixture was cooled to room temperature and acetic acid was added (0.48 g., 8 mmole, pH about 8.5 measured with electrode and about 5 with wet pH paper). The solvent was evaporated under vacuum and the residue was heated in acetone (15 ml.) and filtered. The insoluble material was washed with acetone (5 ml.). The solvent was removed from the filtrate and the residue was washed three times with hexane (5 ml.). The insoluble portion was redissolved in hot acetone (15 ml.). The product crystallized out. After standing overnight in an ice bath, the solid was filtered, washed with acetone (5 ml.), and dried under vacuum over phosphorus pentoxide for three hours to give 1.04 g. of crude product. After 2 days a second crop (0.236 g.) of product was obtained from the mother liquors. These two crops were combined and 1.236 g. of impure product was dissolved in hot ethyl acetate (15 ml.). Silica gel (EM-60, 60 g.) was added and the solvent was removed on a rotary evaporator. This adsorbed material was then charged on a silica gel column (about 25×250 mm) and eluted successively with ethyl acetate (100 ml.), 10% ethanol in ethyl acetate (1700 ml.), and 20% ethanol in ethyl acetate (1100 ml.). The TLC homogeneous fractions were combined and the solvent was removed to give 0.7 g. of the desired product. The solid was heated in acetone (15 ml.) and allowed to stand at room temperature for 7 hours. The product was filtered, washed with acetone and dried over phosphorus pentoxide under vacuum for 15 hours to give 0.55 g. of the desired product; m.p. 144°-1450° C.; α! D =-21.4° (c=1, dimethyl-sulfoxide). TLC(silica gel; ethanol:hexane, 1:1, R f =0.5). Anal. calc'd. for C 12 H 17 N 5 O 3 : C, 51.61; H, 6.13; N, 25.07 Found: C, 51.52; H, 6.07; N, 25.28. EXAMPLE 4 1R-(1α,2β,3α)!-2-Amino-9- 2,3-bis(hydroxymethyl)-cyclobutyl!-1,9-dihydro-6H-purin-6-one a) 6-Chloro-9H-purin-2-amine. ion(1 - ) tetra-butylammonium (1:1) salt An aqueous solution of tetrabutylammonium hydroxide (1.53M, 2.5 ml., 3.83 mmole) was added dropwise to a slurry of 6-chloro-9H-purin-2-amine (1.69 g., 10 mmole) in methylene chloride (40 ml.) at ambient temperature. After 10 minutes the biphasic solution was filtered with suction through a sintered glass funnel to remove a small amount of undissolved solid. The filtrate was transferred to a separatory funnel and the organic layer was separated, dried over magnesium sulfate, and filtered. The filtrate was evaporated under vacuum and the residue was triturated with ethyl acetate (20 ml.) and filtered. The product was dried under vacuum over phosphorus pentoxide at ambient temperature for 5 hours to give 3.41 g. of desired product; m.p. greater than 89° C. Anal. calc'd. for C 21 H 39 N 6 Cl.0.65 H 2 O: C, 59.66; H, 9.61, N, 19.88; Cl, 8.39; H 2 O, 2.79 Found: C, 59.22; H, 9.88, N, 19.86; Cl, 8.74; H 2 O, 2.77. b) 1S-(1α,2β,3α)!-3-(2-Amino-6-chloro-9H-purin-9-yl)-1.2-cyclobutanedimethanol, dibenzoate ester A solution of trifluoromethanesulfonic anhydride (5.97 ml., 35.5 mmole) in dry methylene chloride (10 ml.) was added dropwise over 5 minutes to a solution of 1S-(1α,2β,3α)!-3-hydroxy-1,2-cyclobutane-dimethanol, dibenzoate ester (10.06 g., 29.6 mmole) and pyridine (3.7 ml., 44.4 mmole) in methylene chloride (45 ml.) chilled in an ice bath. After 20 minutes the reaction was quenched with ice, washed into a separatory funnel with methylene chloride, and washed with ice cold water (2×100 ml.), 5% sodium bisulfate (150 ml.), and ice cold water (100 ml.). Each aqueous layer was washed with methylene chloride (10 ml.) which was added to the previous methylene chloride layer. The slightly colored and turbid methylene chloride layer was dried with magnesium sulfate by stirring for 20 minutes and filtered to give an almost clear solution. The solvent was evaporated to 25 ml. and then the solution was diluted to 101 ml. with dry methylene chloride to give a 0.29 molar solution of trifluoromethane-sulfonyloxy compound. The solution was stored over magnesium sulfate under argon at -20° C. 6-Chloro-9H-purin-2-amine, ion (1 - ), tetra-butylammonium (1:1) salt (2.47 g., 6 mmole) was added to the above trifluoromethanesulfonyloxy compound (17.2 ml., 0.29M in methylene chloride, 5 mmole) and the suspension was stirred at room temperature. After 6 hours the reaction flask was stored at -20° C. overnight. After warming to room temperature, the mixture was filtered. Baker silica gel (60-200 mesh, 10 ml.) was added to the filtrate and the solvent was evaporated under vacuum. The solid was charged on a silica gel column (25×260 mm., prepared in 25% ethyl acetate in hexane). The product was eluted successively with 25%, 50%, and 75% ethyl acetate in hexane (100 ml. each) and ethyl acetate (300 ml.) collecting 50 ml. fractions. Fractions 9-12 (TLC, silica gel, ethyl acetate, R f =0.56) were combined and evaporated to give 1.54 g. of desired product. c) 1S-(1α,2β,3α)!-3-(2-Amino-6-chloro-9H-purin-9-yl)-1,2-cvclobutanedimethanol A solution of sodium methoxide (0.39M in methanol, 0.081 ml., 0.32 mmole) was added by syringe to a suspension of 1S-(1α,2β,3α)!-3-(2-amino-6-chloro-9H-purin-9-yl)-1,2-cyclo-butanedimethanol, dibenzoate ester (1.54 g., 3.14 mmole) in dry methanol (20 ml.). After stirring for 2 hours at room temperature the mixture was stored for 2 days at -20° C. The product crystallized during further stirring at room temperature for 2 hours. The mixture was allowed to stand at 0° C. for 3 hours. The solid was filtered, washed with cold methanol, and dried under vacuum to give 0.52 g of desired product; m.p. 198°-201° C. TLC (silica gel; ethanol:ethyl acetate, 1:9, R f =0.49). Anal. calc'd. for C 11 H 14 ClN 5 O 2 : C, 46.43; H, 4.99; N, 24.61; Cl, 12.46; H 2 O, 0.30 Found: C, 46.81; H, 5.01; N, 24.24; Cl, 12.54; H 2 O, 0.36. d) 1R-(1α,2β,3α)!-2-Amino-9- 2,3-bis(hydroxy-methyl)-cyclobutyll-1,9-dihydro-6H-purin-6-one A mixture of 1S-(1α,2β,3α)!-3-(2-amino-6-chloro-9H-purin-9-yl)-1,2-cyclobutanedimethanol and 2N HCl was heated under nitrogen at 95° C. After one hour the mixture was neutralized with 4N sodium hydroxide (about 0.6 ml.) and a few drops of 1N sodium hydroxide to a pH of about 8.0. A thick white precipitate formed. The mixture was stirred in an ice bath for about 1.5 hours, filtered, washed with ice cold water (2 ml.), and dried over phosphorus pentoxide under vacuum to give the desired product. EXAMPLE 5 1S-(1α,2β,3α)!-3-(2-Amino-6-iodo-9H-purin-9-yl)-1.2-cyclobutanedimethanol, dibenzoate ester a) 1S-(1α,2β,3α)!-3- (4-Nitrophenyl)-sulfonyl!-oxy!-1,2-cyclobutanedimethanol, dibenzoate ester p-Nitrobenzenesulfonylchloride (5.9 g., 24.0 mmole) was added to a solution of 1S-(1α,2β,3β)!-3-hydroxy-1,2-cyclobutanedimethanol, dibenzoate ester 6.8 g., 20.0 mmole) in pyridine (20 ml.). After stirring overnight at room temperature, water (8 ml.) was added and the mixture was stirred for one hour. The pyridine was evaporated off and the residue was treated with ethyl acetate (150 ml.). The mixture was washed successively with water, 1% hydrochloric acid, water, 5% sodium bicarbonate, water, and brine. The solution was dried (MgSO 4 ), stirred for 15 minutes with activated charcoal, and filtered through Celite. The solvent was evaporated to give 8.7 g. of crude product. This crude solid was triturated with ether (25 ml.) and then stirred for one hour. The product was filtered, washed with ether, and dried under vacuum to give 7.89 g. of 1S-(1α,2β,3β)!-3- (4-nitrophenyl)sulfonyl!oxy!-1,2-cyclobutane-dimethanol, dibenzoate ester; m.p. 100°-101° C. Anal. calc'd. for C 26 H 23 NO 9 S.0.11 H 2 O: C, 59.19; H, 4.44; N, 2.65; S, 6.08; H 2 O, 0.39 Found: C, 59.17; H, 4.02; N, 2.61; S, 6.19; H 2 O, 0.39. b) 1S-(1α,2β,3α)!-3-(2-Amino-6-iodo-9H-purin-9-yl)-1,2-cyclobutanedimethanol. dibenzoate ester 6-Iodo-9H-purine-2-amine, ion (1 - ), triethyl-(phenylmethyl) ammonium (1:1) salt (4.97 g., 11.0 mmole) was added to a solution of the product from part (a) (5.25 g., 10.0 mmole) in acetonitrile (20 ml.) and the mixture was refluxed for 8.5 hours. The solvent was evaporated and the residue was taken up in ethyl acetate (200 ml.). The solution was washed with water (4×200 ml.), dried (MgSO 4 ), and the solvent was evaporated. The crude product was purified by flash chromatography over silica gel (25×200 mm. column). The product was eluted successively with 500 ml. each of 10%, 30%, 60%, and 80% ethyl acetate in hexane followed by ethyl acetate (500 ml.). Product containing fractions were combined and evaporated to give 3.73 g. of desired product. EXAMPLE 6 1R-(1α,2β,3α)!-2-Amino-9- 2,3-bis(hydroxymethyl)-cyclobutyl!-1,9-dihydro-6H-purin-6-one a) 1R-(1α,2β,3α)!-2-Amino-9- 2,3-bis(benzoyloxy)methyl!cyclobutyl!-1,9-dihydro-6H-purin-6-one A mixture of 1S-(1α,2β,3α)!-3-(2-amino-6-iodo-9H-purin-9-yl)-1,2-cyclobutanedimethanol, dibenzoate ester (1.755 g., 3.0 mmole) and 57% aqueous acetic acid was heated to 100° C. under a nitrogen atmosphere. After 4.5 hours, the solution was cooled and treated with sodium bicarbonate (252 mg., 3.0 mmole). The solvent was evaporated on a rotary evaporator and the residue was dried for one hour under vacuum. The solid was treated with water (10 ml.), filtered, and washed with water. The product was dried under vacuum overnight. The solid was slurried in aqueous sodium bicarbonate (10 ml.). After stirring for 45 minutes, the solid was filtered, washed with water, and dried under vacuum over phosphorus pentoxide to give 1.4 g. of crude product. A solution of the crude product in ethyl acetate was charged on a silica gel column (200 ml., prepared in hexane). The column was eluted successively with 100 ml. of ethyl acetate, 1.5 1. 10% methanol in ethyl acetate, and 500 ml. of 50% methanol in ethyl acetate. Fractions were collected (about 35 ml. each) as soon as the yellow band on the column started to elute. Fractions 3 to 17 gave 1.1 g. of product as a light yellow solid. An analytical sample was obtained by crystallization from ethyl acetate followed by recrystallization from acetone/water to give pure product; m.p. 160°-161° C.; α! D =11.5° (c=1, dimethylformamide). TLC (silica gel; methanol: methylene chloride, 1:9, R f =0.43). Anal. calc'd. for C 25 H 23 N 5 O 5 .0.5 H 2 O: C, 62.23; H, 5.01; N, 14.52; H 2 O, 1.87 Found C, 62.00; H, 4.68; N, 14.56; H 2 O, 1.59. b) 1R-(1α,2β,3α)!-2-Amino-9- 2,3-bis(hydroxy-methyl) cyclobutyl!-1,9-dihydro-6H-purin-6-one A suspension of the product from part (a) (95 mg., 0.2 mmole) in aqueous sodium hydroxide (1 ml., 1N) was heated under argon at 100° C. in an oil bath. After 3 hours, the mixture was cooled to room temperature and acidified with 1N hydrochloric acid to pH 3. Benzoic acid partly crystallized out during acidification. The mixture was washed with methylene chloride (3×2 ml.) to remove the benzoic acid. The pH of the aqueous layer was adjusted to 6 with 1N sodium hydroxide. The aqueous solution (total volume about 7 ml.) was concentrated to about 4 ml. on a rotary evaporator. The product was crystallized out during evaporation. The flask was cooled in an ice bath. After 3 hours, the product was filtered, washed with ice-cold water and dried over phosphorus pentoxide under vacuum to give 48 mg. of desired product as white crystals; m.p. greater than 280° (dec.). Alternatively, the desired final product was also prepared as follows: A suspension of the product from part (a) (95 mg., 0.2 mmole) in methanolic sodium methoxide (2 ml., 0.2M) was refluxed under argon in an oil bath. After 2.5 hours, the mixture was cooled to room temperature and the solvent was evaporated. The residue was treated with 1.5 ml. of 1N hydrochloric acid. The mixture was washed with methylene chloride (3×2 ml.) to remove methyl-benzoate. The pH of the aqueous layer was adjusted to 6 with 1N sodium hydroxide. The product crystallized out in a few minutes. The flask was cooled in an ice bath. After 3 hours, the product was filtered, washed with ice cold water, and dried over phosphorous pentoxide under vacuum overnight to give 42 mg. of product as pale yellow crystals; m.p. 275° (dec.). EXAMPLE 7 3S-(1α,5β,6α)!-2-Amino-1,9-dihydro-9- tetrahydro-5-hydroxy-6-(hydroxymethyl)-2H-pyran-3-yl!-6H-purin-6-one a) (2R-trans)-3-(Acetyloxy)-3,4-dihydro-2H-pyran-2-methanol, acetate (ester) A suspension of sodium borohydride (3.14 g., 83.0 mmole) in anhydrous tetrahydrofuran (226 ml.) and 1,2-dimethoxyethane (113 ml.) was refluxed for 1.5 hours. After cooling, copper(I)bromide (297 mg., 2.07 mmole) was added and the mixture was refluxed for 2 hours. To this slurry was added tri-o-acetyl-D-glucal (11.30 g., 41.53 mmole) and tetrakis-(triphenyl-phosphine)palladium(O) (2.39 g., 2.076 mmole) at room temperature. The mixture was stirred at room temperature overnight, and then heated at 50° C. for 5 hours. The reaction mixture was then cooled to room temperature, treated at 0° C. with saturated sodium bicarbonate (11 ml.) and 30% hydrogen peroxide (22 ml.). The reaction mixture was diluted with ethyl acetate, washed with saturated sodium bicarbonate, dried and concentrated in vacuo. The residue was purified by column chromatography on silica gel, eluting with ethyl acetate (5% to 10%)-hexane with 0.1% triethylamine to give the title compound as a white solid (2.18 g., 10.18 mmole). b) 2R-(2α,3β,5β)!-2- (Acetyloxy)methyl!tetrahydro-2H-pyran-3,5-diol, 3-acetate A 1.0M borane-tetrahydrofuran complex (9.59 ml., 9.59 mmole) was added dropwise at 0° C. under nitrogen to a dry tetrahydrofuran solution (22 ml.) of the product from part (a) (2.055 g., 9.59 mmole). After 2.5 hours, the mixture was treated with saturated sodium bicarbonate (9 ml.) and 30% hydrogen peroxide (4.3 ml.) at 0°-5° C. and stirred for 2 hours. The reaction mixture was cooled to 0° C., diluted with ethyl acetate, washed with sodium bicarbonate, dried and concentrated in vacuo. The crude product was purified by column chromatography on silica gel, eluting with ethyl acetate (50%, 75%)- hexane, to yield the title compound as a colorless oil (0.654 g., R f =0.44) and the epimeric alcohol, 2R-(2α,3β,5α)!-2- (acetyloxy)-methyl!tetrahydro-2H-pyran-3,5-diol, 3-acetate, as a white crystalline solid (0.325 g., R f =0.34). c) 2R-(2α,3β,5α)!-3-(Acetyloxy)-5-(2-amino-6-iodo-9H-purin-9-yl)tetrahydro-2H-pyran-2-methanol, acetate (ester) To a mixture of 6-iodo-2-aminopurine (1.21 g., 4.637 mmole) in methylene chloride (12 ml.) at room temperature, was added 1.5M tetra(n-butyl)ammonium hydroxide (2.7 ml., 4.05 mmole). The reaction mixture was stirred for 10 minutes, and the volatiles were removed in vacuo. Methylene chloride (12 ml.) was added to the white residue, and the resulting solution was dried (magnesium sulfate), filtered, and the filtrate was concentrated in vacuo to yield the tetra(n-butyl)ammonium salt of 6-iodo-2-aminopurine as a white residue. To a stirred solution of 2R-(2α,3β,5β)!-2- (acetyloxy) methyl!tetrahydro-2H-pyran-3,5-diol, 3-acetate (0.633 g., 2.72 mmol) in methylene chloride (12 ml.) at -20° C. was added pyridine (0.33 ml., 4.09 mmole) and trifluoromethanesulfonic anhydride (0.504 ml., 3.0 mmole). The reaction was warmed to room temperature. The mixture was diluted with methylene chloride, washed with 10% sulfuric acid, saturated sodium bicarbonate, and water. The organic layer was separated, dried, and concentrated in vacuo to yield crude trifluoromethanesulfonyl product as a dark pink oil. A solution of this trifluoromethanesulfonyl product in methylene chloride (4 ml.) was added to a mixture of the tetra(n-butyl) ammonium salt of 6-iodo-2-aminopurine in methylene chloride (10 ml.) and the reaction was stirred at room temperature for 16 ours. The mixture was concentrated in vacuo. The residue was dissolved in ethyl acetate (120 ml.) and water (120 ml.), treated for 2 hours with AG-MP 50 cation resin (sodium + form, 30 g.), and filtered through Celite®. The crude product was purified by column chromatography on silica gel, eluting with ethyl acetate (50%,75%,100)-hexane, to yield the title compound as a foamy yellow solid (0.587 g., 1.235 mmole). d) 3S-(3α,5β,6α)!-2-Amino-1,9-dihydro-9- tetrahydro-5-hydroxy-6-(hydroxymethyl)-2H-pyran-3-yl!-6H-purin-6-one Sodium methoxide solution (0.43M, 4.22 ml.) was added to a solution of the product from part (c) (0.58 g., 1.2 mmole) in methanol (5 ml.). The mixture was stirred at room temperature for 45 minutes and then refluxed for 5 hours. After cooling to room temperature, the pH of the mixture was adjusted to 7.0 by the addition of 1N hydrochloric acid (1.4 ml.), and concentrated in vacuo. Additional 1N hydrochloric acid (2.5 ml.) was added to the residue and this mixture was heated at 50° C. for 18 hours and then at 85° C. for 3 hours. The reaction mixture was cooled to room temperature, diluted with water, and the pH adjusted to 7.0 by the addition of 3N sodium hydroxide (0.8 ml.). The mixture was concentrated in vacuo and the residue was subjected to a CHP-20 column, eluting with a continuous gradient (water to 25% acetonitrile in water), to afford a yellow residue. This crude product was triturated in methylene chloride, recrystallized from hot water, and treated with activated charcoal to yield 48 mg. of the title compound as white crystals; α! D =-3.46° (c=0.0866, dimethylsulfoxide). 1 H NMR (270 MHz, DMSO-d 6 ): δ 10.57 (s, 1H,--NH); (s,1H,C8H); 6.47 (s,2H,--NH 2 ); 4.92 (d, J=5.28 Hz, 1H); 4.67-4.62 (t,J=5.86 Hz, 1H); 4,52(s,1H); 4.06(d,J=2.34 Hz,1H); 3.83-3.78 (dd,J=2.34 Hz,12.3 Hz, 1H); 3.66(m,1H); 3.5 (m,1H); 3.16 (m,1H); 2.51 (m,1H); 2.20 (m,1H); 1.85-1.79 (m,1H). 1.R. (KBr pellet): 3435,3194,2648,2903,1697,1639, 1606,1398,1180,1066 cm -1 . Anal. calc'd. for C 11 H 15 N 5 O 4 .0.36 H 2 O: C, 45.90; H, 5.51; N, 24.33 Found: C, 46.07; H, 5.06; N, 24.16. EXAMPLE 8 3S-(3α,4β,5α)!-2-Amino-1,9-dihydro-9- tetrahydro-4,5-bis(hydroxymethyl)-3-furanyl)-6H-purin-6-one a) 3S-(3α,4β,5α)!-6-Iodo-9- tetrahydro-4,5-bis (phenylmethoxy)methyl!-3-furanyl!-9H-purin-2-amine A mixture of 3R-(3α,4α,5β)!-tetrahydro-4,5-bis (phenylmethoxy)methyl!-3-furanol, 4-methyl-benzenesulfonate ester (54.24 g., 112.5 mmole, prepared as described in Example 1 of U.S. Pat. No. 5,059,690) and 6-iodo-9H-purin-2-amine, ion (1 - ), tetrabutylammonium (1:1) salt (89.1 g., 177.5 mmole) in anhydrous dimethylformamide (600 ml.) was heated under nitrogen at 85°-90° C. for 12 hours. The yellow solution was partitioned between water (1.5 l.) and ethyl acetate (1.5 l.). The organic layer was dried (sodium sulfate) and evaporated to give 66 g. of an oil. Chromatography on 5 l. of silica gel (K-60) in ethyl acetate/hexane (2/1) afforded 31.2 g. of the product (R f =0.42, ethyl acetate/hexane, 2/1), which gave a crystalline product on standing; m.p. 84°-86° C. b) 3S-(3α,4β,5α)!-6-Methoxy-9- tetrahydro-4,5-bis (phenylmethoxy)methyl!-3-furanyl!-9H-purin-2-amine A solution of the product from part (a) (31.2 g., 54.64 mmole) in warm methanol (500 ml.) was treated all at once with 10% sodium hydroxide (50 ml.), and then was heated for one hour on a steam cone. The pH was adjusted to 7 with 10% hydrochloric acid (45 ml.) and the mixture was evaporated to a gum. This was partitioned between ethyl acetate and water, the organic layer was dried (sodium sulfate), and evaporated to give 24.9 g. of product as a foam. TLC (silica gel; ethyl acetate) R f =0.57. c) 3S-(3α,4β,5α)!-6-Methoxy-9- tetrahydro-4,5-bis(hydroxymethyl)-3-furanyl!-9H-purin-2-amine All of the product from part (b) was covered with 95% ethanol (800 ml.), 20 g. of 20% palladium hydroxide on carbon catalyst was added, followed by cyclohexene (400 ml.). The mixture was refluxed at 85°-90° C. for 2 hours. The catalyst was filtered on Celite® and the filter cake was washed with methanol (300 ml.). The filtrate was evaporated to give 17.8 g. of the product as an oil. TLC (silica gel; chloroform:methanol:ammonium hydroxide, 6:3:1) R f =0.75. d) 3S-(3α,4β,5α)!-2-Amino-1,9-dihydro-9- tetrahydro-4,5-bis(hydroxymethyl)-3-furanyl!-6H-purin-6-one All of the crude product from part (c) was dissolved in 1N hydrochloric acid (200 ml.) and heated at 70°-75° C. for 10 hours under nitrogen. The resulting solution was cooled to room temperature nd filtered through a Celite® pad. The filtrate was basified to pH of about 8 by the addition of 20 ml. of concentrated ammonium hydroxide. The resulting white slurry was heated on a hot plate until dissolved, then allowed to come to room temperature over 2 hours. The mass of solid was filtered and washed with water (75 ml.), dried as much as possible, and the filter cake was washed with 200 ml. of acetonitrile and finally with 200 ml. of ether. Drying in vacuo gave 11.6 g. of solid, m.p. 240°-245° C., which was 99% pure by electrochromatography. This material was combined with 1.1 g. of product from a smaller run and recrystallized by dissolving in hot water (200 ml.), filtering hot (rapidly), and cooling to room temperature in an ice-bath. The solid was filtered and washed with 100 ml. of cold water. Drying in vacuo over phosphorus pentoxide for 18 hours gave 10.96 g. of product as a white solid; m.p. 270°-275° C. α! D =-46.8° (c=0.22, dimethylsulfoxide). Anal. calc'd. for C 11 H 15 N 5 O 4 .0.23H 2 O.0.088NH 4 Cl: C, 45.54; H, 5.49; N, 24.57; Cl, 1.08 Found: C, 45.54; H, 5.40; N, 24.23; Cl, 1.08.
A purine salt of the formula ##STR1## wherein Y 1 is chloro, bromo, or iodo, and R 1 , R 2 , R 3 , and R 4 are independently selected from alkyl and substituted alkyl is reacted with the compound of the formula Z.sub.1 --X to yield the purine of the formula ##STR2## wherein x is a leaving group, and Z 1 is a protected form of the carbohydrate surrogate Z. Several routes are disclosed for converting this intermediate to the antiviral agent ##STR3##
2
CLAIM PRIORITY This application claims the benefit of Korean Patent Application No. 10-2010-0110996, filed on Nov. 9, 2010 and Korean Patent Application No. 10-2011-0053376, filed on Jun. 2, 2011, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference. BACKGROUND OF THE INVENTION 1. Field of the Invention One or more aspects of the present invention relate to an optical adhesive film and a flat panel display device having the same. 2. Description of the Related Art Various display devices have recently been developed to replace cathode ray tubes. Examples of such display devices include a liquid crystal display (LCD), a field emission display (FED), a plasma display panel (PDP), and an electroluminescent (EL) display. From among these display devices, the PDP has drawn much attention since it has a simple structure, and its manufacturing process is considered most suitable to provide a large screen. However, the PDP has low luminescence efficiency and brightness and consumes a large amount of power. The EL display may be largely classified into an inorganic EL device and an organic EL device according to the material of the emission layer. The EL display is a self-emitting device, and has a quick response time, high luminescence efficiency, high brightness, and wide viewing angles. In particular, an organic light-emitting diode (OLED) display device, which is an EL device using an organic material, requires a low direct-current (DC) driving voltage, can be manufactured as a thin-film display device, can emit light having uniform characteristics, is easy to manufacture in terms of pattern formation, has high luminescence efficiency, and can emit various colors in the visible region. Therefore, research has been actively conducted into the field of OLED display devices. In the case of such an organic EL device, a bottom-emission method or a top-emission method may be established according to the direction in which light is emitted. Also, an organic EL device may be classified into passive organic light-emitting diode (PMOLED) devices and active PMOLED (AMOLED) devices according to the driving method. SUMMARY OF THE INVENTION One or more aspects of the present invention provide an optical adhesive film for improving the adhesive strength between panels of a flat panel display device, and a flat panel display device having the same. According to an aspect of the present invention, there is provided an optical adhesive film for use in a flat panel display module that displays an image, the optical adhesive film including a transmission unit disposed on the flat panel display module which allows an image to transmit through the transmission unit; and a wing member extending from at least one side surface of the transmission unit and substantially covering as least a side surface and at least a portion of a rear surface of the flat panel display module. The transmission unit is autohered to a front surface of the flat panel display module, and the wing member is autohered to side surfaces and the rear surface of the flat panel display module. The transmission unit or the wing member may be directly attached to the flat panel display module without having any member therebetween. The transmission unit or the wing member may be autohered to the flat panel display module due to surface energy therebetween. The wing member may include a base portion extending from a side surface of the transmission unit, a light-shielding member disposed on the base portion, and a reflection member disposed on the light-shielding member. According to an aspect of the present invention, there is provided an optical adhesive film for use in a flat panel display module that displays an image, the optical adhesive film including a transmission unit disposed on the flat panel display module and allowing the image to transmit through the transmission unit; a wing member extending from at least one side surface of the transmission unit, and covering at least one side surface and at least a portion of a rear surface of the flat panel display module; and an adhesive member disposed substantially covering all surfaces of the transmission unit and the wing member. The adhesive member is disposed between the flat panel display module, the transmission unit, and the wing member to bond the flat panel display module, the transmission unit, and the wing member with one another. The transmission unit may allow light emitted from the flat panel display device to pass through the transmission unit. The transmission unit may include a material such as polyethylene terephthalate (PET), a triacetyl cellulose (TAC) film, polyethylene (PE), acryl, or polyolefin. The size of the transmission unit may be equal to or greater than the size of a display region of the flat panel display module, on which the image is displayed. The width of the wing member may be greater than the height of the flat panel display module. The wing member may cover at least a side surface and at least a portion of a rear surface of the flat panel display module. The wing member may include a base portion extending from a side surface of the transmission unit; a light-shielding member disposed on the base portion; and a reflection member disposed on the light-shielding member. The base portion may be combined with the transmission unit as one body. The base portion may include a material such as polyethylene terephthalate (PET), a triacetyl cellulose (TAC) film, polyethylene (PE), acryl, or polyolefin. The light-shielding member may absorb external light incident via the base portion. The light-shielding member may include paint or pigment that absorbs visible light. The size of the light-shielding member may be equal to or greater than the size of the reflection member. The light-shielding member may be disposed substantially on the entire wing member and a portion of the transmission unit. The reflection member may reflect light emitted from the flat panel display module, thereby preventing the light from leaking to the outside The reflection member may include paint or pigment that absorbs light. The adhesive member may allow light to penetrate through. According to another aspect of the present invention, there is provided a flat panel display device including a flat panel display module for displaying an image; and an optical adhesive film adhered onto, not only front and side surfaces of the flat panel display module, but also a portion of a rear surface of the flat panel display module. The image displayed on the front surface of the flat panel display module is output via the optical adhesive film. The optical adhesive film may include a transmission unit disposed on the front surface of the flat panel display module and allowing the image to transmit through the transmission unit; a wing member extending from at least one side surface of the transmission unit, and covering the side surface and the portion of the rear surface of the flat panel display module; and an adhesive member substantially disposed over the transmission unit and the wing member. The adhesive member is disposed between the flat panel display module, the transmission unit, and the wing member so as to bond the flat panel display module, the transmission unit, and the wing member with one another. The transmission unit may allow light emitted from the flat panel display module to transmit through the transmission unit. The transmission unit may include a material such as polyethylene terephthalate (PET), a triacetyl cellulose (TAC) film, polyethylene (PE), acryl, or polyolefin. The size of the transmission unit may be equal to or greater than the size of a display region of the flat panel display module, on which the image is displayed. The width of the wing member may be greater than the height of the flat panel display module. The wing member may cover the side surface and a portion of the rear surface of the flat panel display module. The wing member may include a base portion extending from at least one side surface of the transmission unit; a light-shielding member disposed on the base portion; and a reflection member disposed on the light-shielding member. The base portion may be combined with the transmission unit as one body. The base portion may include a material such as polyethylene terephthalate (PET), a triacetyl cellulose (TAC) film, polyethylene (PE), acryl, or polyolefin. The light-shielding member may absorb external light incident via the base portion. The light-shielding member may include paint or pigment that absorbs visible light. The size of the light-shielding member may be equal to or greater than the size of the reflection member. The light-shielding member may be disposed on the entire wing member and a portion of the transmission unit. The reflection member may reflect light emitted from the flat panel display module, thereby preventing the light from leaking to the outside. The reflection member may include paint or pigment that absorbs light. The flat panel display module may have a structure, in which a backlight unit, a polarizing plate, and a liquid crystal panel are sequentially stacked. According to another aspect of the present invention, there is provided a flat panel display device including a flat panel display module for displaying an image; and an optical adhesive film autohered onto, not only on front and side surfaces of the flat panel display module, but also on a portion of a rear surface of the flat panel display module. The image displayed on the front surface of the flat panel display module is output via the optical adhesive film. The optical adhesive film is directly adhered onto the flat panel display module due to surface energy therebetween and without having any member between the optical adhesive film and the flat panel display module. The optical adhesive film may include a transmission unit disposed on the front surface of the flat panel display module and allowing the image to transmit through the transmission unit, and a wing member extending from at least one side surface of the transmission unit and covering the side surfaces and a portion of a rear surface of the flat panel display module. The transmission unit may be attached to the front surface of the flat panel display module, and the wing member may be autohered to the side surfaces and the rear surface of the flat panel display module. The wing member may include a base portion extending from a side surface of the transmission unit, a light-shielding member disposed on the base portion, and a reflection member disposed on the light-shielding member. BRIEF DESCRIPTION OF THE DRAWINGS The above and other features of the present invention will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings in which: FIG. 1 is a schematic plane view of an optical adhesive film according to an embodiment of the present invention; FIG. 2 is a cross-sectional view taken along the line I-I of FIG. 1 ; FIG. 3 is a cross-sectional view taken along the line II-II of FIG. 1 ; FIG. 4 is a schematic exploded perspective view of a flat panel display device that includes the optical adhesive film of FIG. 1 , according to an embodiment of the present invention; FIG. 5 is a schematic perspective view of the flat panel display device of FIG. 4 ; FIG. 6 is a cross-sectional view of a portion of the flat panel display device of FIG. 4 ; FIG. 7 is a cross-sectional view of a flat panel display device according to another embodiment of the present invention; FIG. 8 is a cross-sectional view of a flat panel display device according to another embodiment of the present invention; and FIG. 9 is a cross-sectional view of a flat panel display device according to another embodiment of the present invention. DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in greater detail with reference to the accompanying drawings. An active LCD that uses a thin film transistor (TFT) as a switch device is manufactured using a semiconductor manufacturing process, and it is thus difficult to provide a large screen, but has come into widespread use as a display device for notebook computers. An LCD is a non self-emitting device, and may include a liquid crystal panel and a backlight unit. The backlight unit is disposed below the liquid crystal panel, and is bonded with the liquid crystal panel via double-faced adhesive tape. FIG. 1 is a schematic plane view of an optical adhesive film 100 according to an embodiment of the present invention. FIG. 2 is a cross-sectional view taken along the line I-I of FIG. 1 . FIG. 3 is a cross-sectional view taken along the line II-II of FIG. 1 . Referring to FIGS. 1 to 3 , the optical adhesive film 100 includes a transmission unit 110 , a first wing member 111 , a second wing member 112 , a third wing member 113 , first, second, and third light-shielding members 111 b , 112 b , and 113 b , first, second, and third reflection members 111 c , 112 c , and 113 c , and an adhesive member 114 . The transmission unit 110 is disposed on a display region 10 a of a flat panel display device 1000 illustrated in FIGS. 4 and 5 . The transmission unit 110 may allow light emitted from the flat panel display device 1000 to transmit through. The transmission unit 110 may be formed of a material having high permeability to visible light. For example, the transmission unit 110 may be formed of a material such as polyethylene terephthalate (PET), a triacetyl cellulose (TAC) film, polyethylene (PE), acryl, or polyolefin. The transmission unit 110 is disposed on a display region 10 a of the flat panel display device 1000 and may thus have a shape corresponding to that of the display region 10 a . Referring to FIGS. 4 and 5 , a flat panel display module 10 has a rectangular shape, and the transmission unit 110 of the optical adhesive film 100 may thus have a rectangular shape corresponding to the shape of the display region 10 a of the flat panel display module 10 . The first to third wing members 111 to 113 may extend from first to third side surfaces 110 a , 110 b , and 110 c of the transmission unit 110 , respectively. When the first to third wing members 111 to 113 of the optical adhesive film 100 are folded, not only side portions of the flat panel display module 10 but also a portion of a rear surface of the flat panel display module 10 may be covered with the first to third wing members 111 to 113 . Specifically, when the first wing member 111 of the optical adhesive film 100 is folded, a side surface 10 c of the flat panel display module 10 and a portion of the rear surface of the flat panel display module 10 are covered with the first wing member 111 . When the second wing 112 of the optical adhesive film 100 is folded, a side surface 10 d of the flat panel display module 10 and a portion of the rear surface of the flat panel display module 10 are covered with the second wing member 112 . When the third side of the transmission unit 110 is folded, a top side surface 10 e of the flat panel display module 10 and a portion of the rear surface of the flat panel display module 10 are covered with the third wing member 113 . Widths t 1 , t 2 , and t 3 of the first to third wing members 111 to 113 may be greater than a thickness of the flat panel display module 10 . In the current embodiment, the optical adhesive film 100 covers the entire display region 10 a of the flat panel display device 1000 and the side and portions of the rear surfaces of flat panel display module 10 , thereby improving adhesive strength between the constitutional elements of the flat panel display module 10 , as will be described in detail later. The first wing member 111 may include a first base portion 111 a , the first light-shielding member 111 b , and the first reflection member 111 c . The second wing member 112 may include a second base portion 112 a , the second light-shielding member 112 b , and the second reflection member 112 c . The third wing member 113 may include a third base portion 113 a , the third light-shielding member 113 b , and the third reflection member 113 c. That is, the first wing member 111 may include the first base portion 111 a , the first light-shielding member 111 b on the first base portion 111 a , and the first reflection member 111 c on the first light-shielding member 111 b. The second wing member 112 may include the second base portion 112 a , the second light-shielding member 112 b on the second base portion 112 a , and the second reflection member 112 c on the second light-shielding member 112 b. The third wing member 113 may include the third base portion 113 a , the third light-shielding member 113 b on the third base portion 113 a , and the third reflection member 113 e on the third light-shielding member 113 b. The first to third base portions 111 a to 113 a may extend from the first to third side surfaces 110 a to 110 c of the transmission unit 110 , respectively. The first to third base portions 111 a to 113 a may be formed of the same material as the transmission unit 110 . That is, the first to third base portions 111 a to 113 a may be formed of a material such as PET, a TAC film, PE, acryl, or polyolefin, similar to the transmission unit 110 . The first to third light-shielding members 111 b to 113 b may be disposed on surfaces of the first to third base portions 111 a to 113 a , respectively. For example, the first light-shielding member 111 b may be disposed on the first base portion 111 a , the second light-shielding member 112 b may be disposed on the second base portion 112 a , and the third light-shielding member 113 may be disposed on the third base portion 113 a . The first to third light-shielding members 111 b to 113 b may be formed of paint or pigment that absorbs light, and may be formed by applying such paint or pigment onto surfaces of the first to third base portions 111 a to 113 a , respectively. The first to third light-shielding members 111 b to 113 b may absorb external light incident on a side surface of the flat panel display device 1000 . The first to third reflection members 111 c to 113 c may be formed on the first to third light-shielding members 111 b to 113 b , respectively. The first to third reflection members 111 c to 113 c may be formed of paint or pigment that reflects light, and may be formed by applying such paint or pigment onto the first to third light-shielding members 111 b to 113 b , respectively. The first to third reflection members 111 c to 113 c are disposed facing the flat panel display module 10 , and reflect light emitted from the flat panel display module 10 , thereby preventing the light from leaking via a side surface of the flat panel display module 10 . The adhesive member 114 may be disposed covering a surface of the transmission unit 110 and the first to third reflection members 111 c to 113 c . The adhesive member 114 allows the optical adhesive film 100 to be adhered onto the flat panel display module 10 . According to another embodiment of the present invention, the optical adhesive film 100 may be autohered to the flat panel display module 10 without having to use the adhesive member 114 . Here, autohesion is a type of adhesion whereby two types of polymers and an inorganic surface are united with each other by not using tacks therebetween but using the force of surface energy, for example, via wetting, magnetism, or electric charges. According to another embodiment of the present invention, the optical adhesive film 100 may be autohered to the flat panel display module 10 due to surface energy therebetween. That is, the transmission unit 110 of the optical adhesive film 100 may be autohered to a front surface of the flat panel display module 10 , and the first to third wing members 111 to 113 may be autohered not only to side surfaces of the flat panel display module 10 but also to a portion of the rear surface of the flat panel display module 10 . FIG. 4 is a schematic exploded perspective view of the flat panel display device 1000 that includes the optical adhesive film 100 of FIG. 1 , according to an embodiment of the present invention. FIG. 5 is a schematic perspective view of the flat panel display device 1000 of FIG. 4 . Referring to FIGS. 4 and 5 , the flat panel display device 1000 includes the flat panel display module 10 and the optical adhesive film 100 . The flat panel display module 10 may be a liquid crystal display device or an organic light-emitting diode display device. The optical adhesive film 100 may be adhered onto a front surface of the flat panel display module 10 . More specifically, the flat panel display module 10 may include the display region 10 a for displaying an image, and a pad region 10 b to connect to an external circuit (not shown). The transmission unit 110 of the optical adhesive film 100 is disposed correspondingly on the display region 10 a of the flat panel display module 10 . The first to third wing members 111 to 113 may be bonded with the flat panel display module 10 and cover side portions and a portion of a rear surface of the flat panel display module 10 . Specifically, the first wing member 111 is bonded with the flat panel display module 10 to cover the side surface 10 c and a portion of the rear surface of the flat panel display module 10 . The second wing member 112 is bonded with the flat panel display module 10 to cover the side surface 10 d and a portion of the rear surface of the flat panel display module 10 . The third wing member 113 is bonded with the flat panel display module 10 and covers the top side surface 10 e and a portion of the rear surface of the flat panel display module 10 . The first to third wing members 111 to 113 may be bonded with the side and rear surfaces of the flat panel display module 10 in the form of ‘C’. However, no wing member is formed at a bottom side of the transmission unit 110 (which corresponds to a bottom side surface 110 d of FIG. 1 ), and the transmission unit 110 is disposed to correspond to the display region 10 a of the flat panel display module 10 . Accordingly, the optical adhesive film 100 is not disposed on the pad region 10 b of the flat panel display module 10 , and the pad region 10 b is exposed. If the flat panel display module 10 is a liquid crystal display device, conventionally, a liquid crystal panel and a backlight unit are bonded with each other by adhering a double-faced tape onto a rear surface of the liquid crystal panel and a front surface of the backlight unit. However, the optical adhesive film 100 according to the current embodiment may be adhered onto all of a front surface (which corresponds to the display region 10 a of FIGS. 4 and 5 ) and side and rear surfaces of the liquid crystal display device with the transmission unit 110 and the first to third wing members 111 to 113 , thereby improving adhesive strength between the liquid crystal panel and the backlight unit. The first, second, and third light-shielding members 111 b , 112 b , and 113 b and the first to third reflection members 111 c to 113 c are stacked on surfaces of the first to third wing members 111 to 113 , and the first to third reflection members 111 c to 113 c are disposed facing the flat panel display module 10 . Thus, light emitted from a side surface of the flat panel display module 10 is reflected by the first to third reflection members 111 c to 113 c , thereby preventing light from leaking via the side surface of the flat panel display module 10 . Furthermore, since the first to third light-shielding members 111 c to 113 c are disposed between the first to third reflection members 111 c to 113 c and the first to third base portions 111 a to 113 a , the first to third light-shielding members 111 c to 113 c may prevent external light from being incident into the flat panel display module 10 . Since the first to third wing members 111 to 113 extend to, and are bonded with, the side and rear surfaces of the flat panel display module 10 , foreign substances or moisture may be prevented from entering the flat panel display device 1000 via a side surface of the flat panel display module 10 . According to another embodiment of the present invention, the flat panel display device 1000 may be autohered to the optical adhesive film 100 and the flat panel display module 10 without having to use an additional member, e.g., an adhesive member, between the optical adhesive film 100 and the flat panel display module 10 . In this case, the optical adhesive film 100 includes the transmission unit 110 and the first to third wing members 111 , 112 , and 113 . The transmission unit 110 is autohered to the front surface of the flat panel display module 10 , and the first to third wing members 111 to 113 is autohered to not only side surfaces of the flat panel display module 10 but also a portion of the rear surface of the flat panel display module 10 . The first wing member 111 may include the first base portion 111 a , the first light-shielding member 111 b , and the first reflection member 111 c . The second wing member 112 may include the second base portion 112 a , the second light-shielding member 112 b , and the second reflection member 112 c . The third wing member 113 may include the third base portion 113 a , the third light-shielding member 113 b , and the third reflection member 113 c . Since the first to third reflection members 111 c to 113 c contact the side and rear surfaces of the flat panel display module 10 , the first to third reflection members 111 c to 113 c are autohered to the side and rear surfaces of the flat panel display module 10 . FIG. 6 is a cross-sectional view of a portion of the flat panel display device 1000 of FIG. 4 . In detail, FIG. 6 illustrates a case where the flat panel display module 10 is a liquid crystal display device (hereafter the flat panel display module 10 will be referred to as the liquid crystal display device 10 ). The liquid crystal display device 10 may include a backlight unit 11 , a polarizing plate 13 , and a liquid crystal panel 12 . The polarizing plate 13 may be disposed between the backlight unit 11 and the liquid crystal panel 12 . In other words, the liquid crystal display device 10 may have a structure in which the polarizing plate 13 and the liquid crystal panel 12 are sequentially stacked on the flat panel display module 10 . The transmission unit 110 of the optical adhesive film 100 may be disposed on a front surface of the liquid crystal panel 12 , and is bonded with the front surface of the liquid crystal panel 12 via the adhesive member 114 . The first wing member 111 may extend from a side surface of the transmission unit 110 , and may be bonded with a side surface and a portion of a rear surface of the liquid crystal panel 12 via the adhesive member 114 . As described above, in the current embodiment, the optical adhesive film 100 is adhered onto the liquid crystal display device 10 to cover the front, side, and rear surfaces of the liquid crystal display device 10 . The transmission unit 110 is bonded with the front surface of the liquid crystal panel 12 , and is formed of a material having high permeability to visible light. Thus, an image, output via the liquid crystal panel 12 , may be displayed through the transmission unit 110 . In the optical adhesive film 100 according to the current embodiment, the adhesive member 114 is disposed on front surfaces of the transmission unit 110 and the first wing member 111 . The optical adhesive film 100 according to the current embodiment may be adhered onto all of a front surface (which corresponds to the display region 10 a of FIGS. 4 and 5 ) and side and rear surfaces of the liquid crystal display device 10 with the transmission unit 110 and the first to third wing members 111 to 113 , thereby improving an adhesive strength between the liquid crystal panel 12 and the backlight unit 11 of the liquid crystal display device 10 . The first wing member 111 may include the first base portion 111 a , the first light-shielding member 111 b , and the first reflection member 111 c . The first base portion 111 a extends from a side surface of the transmission unit 110 . The first light-shielding member 111 b and the first reflection member 111 c are stacked on the first base portion 111 a . Then, the adhesive member 114 is disposed on the first reflection member 111 c. The first reflection member 111 c is disposed facing the liquid crystal display device 10 , and reflects light emitted from the liquid crystal display device 10 , thereby preventing the light from leaking to the outside. The first reflection member 111 c may be disposed to correspond to the side and rear surfaces of the liquid crystal display device 10 . The first light-shielding member 111 b is disposed covering an outer surface of the first reflection member 111 c , and absorbs external light from the outside, thereby preventing the external light from being incident into the liquid crystal display device 10 . The first light-shielding member 111 b may be disposed on, not only the side and rear surfaces of the liquid crystal display device 10 , but also on a portion of the front surface of the liquid crystal display device 10 . A polarizing film 14 may be disposed on the transmission unit 110 . FIG. 7 is a cross-sectional view of a flat panel display device 2000 according to another embodiment of the present invention. Referring to FIG. 7 , the flat panel display device 2000 may include a liquid crystal display device 20 and an optical adhesive film 200 . The liquid crystal display device 20 may have a structure, in which a backlight unit 21 , a polarizing plate 23 , a liquid crystal panel 22 , and a polarizing film 24 are sequentially stacked. The optical adhesive film 200 may include a transmission unit 210 , a first wing member 211 , and an adhesive member 214 . The transmission unit 210 of the optical adhesive film 200 may be bonded with the polarizing film 24 on the liquid crystal panel 22 via the adhesive member 214 . The first wing member 211 may extend from a side surface of the transmission unit 210 , and may be bonded with a side surface and a portion of a rear surface of the liquid crystal display device 20 via the adhesive member 214 . As described above, the optical adhesive film 200 may be adhered onto the liquid crystal display device 10 to cover all of a front surface and the side and rear surfaces of the liquid crystal display device 20 , thereby improving adhesive strength between the constitutional elements of the liquid crystal display device 20 . The transmission unit 210 is adhered onto the entire liquid crystal panel 22 , and is formed of a material having high permeability to visible light, as described above. Thus, an image, output via the liquid crystal panel 22 , may be displayed by using the transmission unit 210 . In the optical adhesive film 200 , the adhesive member 214 is disposed over the transmission unit 210 and the first wing member 211 . The first wing member 211 may include a base portion 211 a , a light-shielding member 211 b , and a reflection member 211 c . The base portion 211 a extends from a side surface of the transmission unit 210 . The light-shielding member 211 b and the reflection member 211 c are stacked on the base portion 211 a. The reflection member 211 c is disposed facing the liquid crystal display device 20 , and reflects light emitted from the liquid crystal display device 20 , thereby preventing the light from leaking to the outside. The reflection member 211 c may be disposed to correspond to the side and rear surfaces of the liquid crystal display device 20 . The light-shielding member 211 b is disposed covering an outer surface of the reflection member 211 c , and absorbs external light from the outside, thereby preventing the external light from being incident into the liquid crystal display device 20 . The light-shielding member 211 b may be wider than the reflection member 211 c . The reflection member 211 c is disposed on the base portion 211 a to cover the side and rear surfaces of the liquid crystal display device 20 , but the light-shielding member 21 lb may be disposed on not only the side and rear surfaces of the liquid crystal display device 10 but also on the front surface of the liquid crystal display device 20 . FIG. 8 is a cross-sectional view of a flat panel display device 3000 according to another embodiment of the present invention. Referring to FIG. 8 , the flat panel display device 3000 may include a liquid crystal display device 30 and an optical adhesive film 300 . The liquid crystal display device 30 may have a structure, in which a chassis 35 , a backlight unit 31 , a polarizing plate 33 , a liquid crystal panel 32 , and a polarizing film 34 are sequentially stacked. The optical adhesive film 300 may include a transmission unit 310 , a wing member 311 , and an adhesive member 314 . The transmission unit 310 of the optical adhesive film 300 is bonded with the polarizing film 34 on the liquid crystal panel 32 via the adhesive member 314 . The wing member 311 may extend from a side surface of the transmission unit 310 , and may be bonded with a side surface and a portion of a rear surface of the liquid crystal display device 30 via the adhesive member 314 . That is, the wing member 311 may extend to a rear surface of the chassis 35 and may be bonded with the rear surface of the chassis 35 via the, adhesive member 314 . As described above, the optical adhesive film 300 is adhered onto the liquid crystal display device 30 to cover the front, side, and rear surfaces of the liquid crystal display device 30 , thereby improving adhesive strength between the constitutional elements of the liquid crystal display device 30 . The transmission unit 310 is bonded with the entire liquid crystal panel 32 , and is formed of a material having high permeability to visible light. Thus, an image output via the liquid crystal panel 32 may be displayed using the transmission unit 310 . In the optical adhesive film 300 , the adhesive member 314 is disposed over the transmission unit 310 and the wing member 311 . The wing member 311 may include a base portion 311 a , a light-shielding member 311 b , and a reflection member 311 c . The base portion 311 a extends from a side surface of the transmission unit 310 . The light-shielding member 311 b and the reflection member 311 c are stacked on the base portion 311 a. The reflection member 311 c is disposed facing the liquid crystal display device 30 , and reflects light emitted from the liquid crystal display device 30 , thereby preventing the light from leaking to the outside. The reflection member 311 c may be disposed to correspond to the side and rear surfaces of the liquid crystal display device 30 . The light-shielding member 311 b is disposed covering an outer surface of the reflection member 311 c , and absorbs external light from the outside, thereby preventing the external light from being incident into the liquid crystal display device 30 . The light-shielding member 311 b may be wider than the reflection member 311 c . The reflection member 311 c is disposed on the base portion 311 a to cover the side and rear surfaces of the liquid crystal display device 30 , but the light-shielding member 311 b may be disposed on all the side, rear, and front surfaces of the liquid crystal display device 30 . FIG. 9 is a cross-sectional view of a flat panel display device 4000 according to another embodiment of the present invention. Referring to FIG. 9 , the flat panel display device 4000 may include a liquid crystal display device 40 and an optical adhesive film 400 . The liquid crystal display device 40 may have a structure, in which a chassis 45 , a backlight unit 41 , a polarizing plate 43 , a liquid crystal panel 42 , a polarizing film 44 , and a touch panel 47 are sequentially stacked. The optical adhesive film 400 may include a transmission unit 410 , a wing member 411 , and an adhesive member 414 . The transmission unit 410 of the optical adhesive film 400 may be bonded with the touch panel 47 on the liquid crystal panel 32 via the adhesive member 414 . The wing member 411 may extend from a side surface of the transmission unit 410 , and may be bonded with the side surface and a portion of a rear surface of the liquid crystal display device 40 via the adhesive member 414 . That is, the wing member 411 may extend to a rear surface of the chassis 45 and may be bonded with the rear surface of the chassis 45 via the adhesive member 414 . As described above, the optical adhesive film 400 is adhered onto the liquid crystal display device 40 to cover all the front, side, and rear surfaces of the liquid crystal display device 40 , thereby improving adhesive strength between the constitutional elements of the liquid crystal display device 40 . The transmission unit 410 is bonded with the entire liquid crystal panel 42 , and is formed of a material having high permeability to visible light. Thus, an image output via the liquid crystal panel 42 may be displayed using the transmission unit 410 . In the optical adhesive film 400 , the adhesive member 414 is disposed over the transmission unit 410 and the wing member 411 . The wing member 411 may include a base portion 411 a , a light-shielding member 411 b , and a reflection member 411 c . The base portion 411 a extends from a side surface of the transmission unit 410 . The light-shielding member 411 b and the reflection member 411 c are stacked on the base portion 411 a. The reflection member 411 c is disposed facing the liquid crystal display device 40 , and absorbs light emitted from the liquid crystal display device 40 , thereby preventing the light from leaking to the outside. The reflection member 411 c may be disposed to correspond to the side and rear surfaces of the liquid crystal display device 40 . The light-shielding member 411 b may be disposed covering an outer surface of the reflection member 411 c , and may absorb external light from the outside, thereby preventing the external light from being incident into the liquid crystal display device 40 . The light-shielding member 411 b may be wider than the reflection member 411 c . The reflection member 411 c is disposed on the base portion 411 a to cover the side and rear surfaces of the liquid crystal display device 40 , but the light-shielding member 411 b may be disposed on all the side, rear, and front surfaces of the liquid crystal display device 40 . According to an embodiment of the present invention, an optical adhesive film is adhered onto not only a front surface of a flat panel display module but also side and rear surfaces of the flat panel display module, thereby improving adhesive strength between the constitutional elements of the flat panel display module. While this invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.
An optical adhesive film for improving the adhesive strength between constitutional elements of a flat panel display device, and a flat panel display device having the same. According to an aspect of the present invention, there is provided an optical adhesive film for use in a flat panel display module that displays an image, the optical adhesive film including a transmission unit disposed on the flat panel display module and allowing the image to transmit through the transmission unit; a wing member extending from at least one side surface of the transmission unit, and covering side surfaces and a portion of a rear surface of the flat panel display module; and an adhesive member disposed covering all surfaces of the transmission unit and the wing member.
6
CROSS REFERENCE TO RELATED APPLICATIONS Applicant claims priority under 35 U.S.C. 119 of German Application No. 10 2008 061 440.8 filed Dec. 10, 2008. BACKGROUND OF THE INVENTION 1. Field of the Invention The invention relates to a valve drive for activation of gas exchange valves of internal combustion engines. 2. The Prior Art It is known to operate gas exchange valves of an internal combustion engine variably with different opening and closing time points, as well as with different valve opening strokes. Such a valve control is described in German Patent Application No. DE 42 30 877 A1. In this connection, a camshaft block having two different cam contours is disposed on a camshaft so as to rotate with it, but in an axially displaceable manner. Depending on the axial position of the cam block, a cam contour stands in a functional connection with the stroke valve, by way of an intermediate element (transfer lever). The axial displacement of the cam block for changing the valve parameters takes place during the base circle phase, counter to the effect of a reset spring, by means of a pressure ring. German Patent Application No. DE 35 20 859 A1 describes an internal combustion engine having at least one camshaft driven by a crankshaft, for activation of inlet and outlet valves. Two cams having different structures, in terms of their cam contour, and placed directly next to one another are disposed on the camshaft; these cams determine the opening and closing time point and the opening stroke in accordance with their configuration, taking the valve play into account. During passage through the cam base circle, which has the same shape in both cams, an adjustable intermediate piece is displaced, by way of a shift rod and a lever, in such a manner that optionally, one of the two cams can be brought into a functional connection with the valve. German Patent Application No. DE 195 19 048 A1 describes a variable valve drive for an internal combustion engine, in which again, two cams having different structures, in terms of their cam contour, and placed directly next to one another are disposed on the camshaft. The change in cam engagement takes place by axial displacement of the camshaft with the cam situated on it. Furthermore, a valve drive of an internal combustion engine is described in German Patent Application No. DE 195 20 117 C2, in which an axially displaceable cam block having at least two different cam paths is disposed on the camshaft, so as to rotate with it. The adjustment of the cam block takes place by way of an adjustment organ that is guided in the interior of the camshaft. The adjustment organ is displaced in the interior of the camshaft by a dual-action hydraulic or pneumatic piston/cylinder unit disposed on the face side of the camshaft. The adjustment organ is connected with an entrainment piece that penetrates an oblong hole disposed axially in the camshaft, and ends in a bore of the cam block. German Patent Application No. DE 100 54 623 A1 describes a device for switching over a cam package on a camshaft, to activate gas exchange valves, in which the cam package is guided on the camshaft in an axially displaceable manner. The gas exchange valve is in a functional connection with different cam contours, in accordance with the position of the cam package. The adjustment of the cam package takes place by way of a setting element in interaction with a gate track. The setting element is a pin that can be displaced radially to the outside, which interacts, in the moved-out state, with at least two gate tracks formed in a guide part disposed around the cam package by approximately 180°. A disadvantage of the cited prior art is the great need for construction space that is required to adjust the cam block. These solutions can therefore be used only in the case of relatively large cylinder distances, so that the corresponding components can be accommodated. Another disadvantage is the great mass forces that occur during the setting process, which are required for displacing the cam blocks or the adjustment organs. Switching to a corresponding cam contour can generally take place only cylinder-selectively with the solutions named in the prior art. Valve-selective switching is not possible. A significant disadvantage of DE 100 54 623 A1 is that in order to switch to a different cam contour, the pin has to be moved out of the camshaft and tracked into an axially displaceable shift gate. After the switching process, the pin has to be moved back in again. This design is very parts-intensive and production-intensive, and there is the risk of damage to the camshaft, resulting from incorrect shifting of the pin. A further disadvantage is that the engine speed of rotation is limited because of the required adjustment time of the pin. Furthermore, the adjustment is dependent on the oil pressure that is present. German Patent Application No. DE 10 2004 033 798 A1 describes a valve stroke switching mechanism for gas exchange valves in an internal combustion engine, between two different cam contours, by means of a shift gate disposed on the housing of the internal combustion engine so as not to rotate, but in an axially displaceable manner. The shift gate partly surrounds the camshaft and is provided with a gate groove that widens opposite to the direction of rotation of the camshaft, the side walls of which groove each form a gate flank that can be brought reciprocally into a functional connection with a contact surface disposed on an axially displaceable second cam contour, on both sides, laterally, in order to switch the valve stroke. During valve stroke switching, the axially displaceable second cam contour is either pushed over the cam contour of the cam that is firmly connected with the camshaft, by means of the shift gate, or pushed away from the cam contour, so that optionally, two different cam contours can be brought into a functional connection with the gas exchange valve. SUMMARY OF THE INVENTION It is therefore an object of the invention to create a valve drive of the type stated, for activation of gas exchange valves of internal combustion engines, with which valve stroke switching is carried out with little technical effort, a low construction height, and at low switching forces to be applied, whereby incorrect switching and damage to the camshaft during valve stroke switching are avoided even at high engine speeds of rotation. According to the invention, this task is accomplished by a valve drive for activation of gas exchange valves of internal combustion engines, having at least one camshaft driven by the crankshaft of the internal combustion engine, axially displaceable cams disposed on the camshaft, which stand in a functional connection, directly or by way of intermediate elements, with the gas exchange valve, and a shift gate disposed on the housing of the internal combustion engine; in an axially displaceable manner. The gate is provided with a gate groove that widens counter to the direction of rotation of the camshaft, and which can be brought into a functional connection with contact surfaces of a displaceable cam contour, for valve stroke switching between at least two different cam profiles. For activation of the valve stroke switching, an adjustment shaft that can be rotated by the camshaft is disposed parallel to the camshaft, and two adjustment devices are disposed on this shaft so as to rotate with it, along with two tappets that are axially displaceable on the adjustment shaft, between the adjustment devices. The tappets are firmly connected with the axially displaceable shift gate for valve switching between at least two different cam profiles of a cam package that is axially displaceable on the camshaft. The face sides of the tappets that are disposed between the adjustment devices are each provided with a contour, which contours stand in a functional connection with one another by way of a guide pin or a counter contour that is attached to the adjustment device, in each instance. In this connection, the contours of the two tappets are disposed offset by 180°. By rotating the adjustment shaft, the tappets are axially displaced on the adjustment shaft by the guide pins or counter contours that slide on the contour. The adjustment shaft is driven by the camshaft. Camshaft can be brought into engagement with the adjustment shaft by a shiftable gear mechanism. The gear mechanism is adapted to drive the adjustment shaft a defined angle by each rotation of the camshaft. Shifting of the gear mechanism is designed to allow a temporarily engagement of the gear mechanism so that gear mechanism can be brought into or out of engagement during each rotation of the camshaft. The engagement of the cam mechanism can so be limited to a single rotation of the cam shaft to drive the adjustment shaft a defined angle range for example 90° or 180°. A first embodiment of the gear mechanism has a gear wheel on the adjustment shaft. The gear wheel is disposed so as to rotate with the shaft, but in axially displaceable manner, which gear wheel is brought into engagement with a gear segment disposed on the camshaft, by a drive disposed on the adjustment shaft, in order to rotate the adjustment shaft. An alternative embodiment of the gear mechanism has a shift cam and a lever system. The lever system which is disposed on the adjustment shaft so as to rotate with it has at least two lever arms. The shift cam is in an axially displaceable manner disposed on the camshaft so as to rotate with it. The shift cam can be brought into engagement with the lever system to drive the adjustment shaft. The advantage of the solution according to the invention consists in that reliable valve stroke switching between different cam contours takes place with little effort and little required construction space. Because of the controlled rotation of the adjustment shaft by way of the camshaft, and thus the compulsorily controlled displacement of the shift gate, incorrect switching positions during valve stroke switching are avoided. In a preferred embodiment, a cam package can be disposed on the camshaft so as to rotate with it. The cam package is firmly connected with a pin in an axially displaceable manner. The pin can be brought into engagement with the insides of the gate groove of the shift gate, which groove widens counter to the direction of rotation of the camshaft. In another embodiment, the gear segment disposed on the camshaft is disposed in such a manner that an axial displacement of the shift gate by means of the pin only takes place during engagement of the base circle profile of the camshaft with the gas exchange valve. A spring can be disposed on the gear wheel, the spring force of which is directed counter to the displacement direction of the drive. The adjustment device can be provided with a locking device consisting of a spring and a ball. BRIEF DESCRIPTION OF THE DRAWINGS Other objects and features of the present invention will become apparent from the following detailed description considered in connection with the accompanying drawings. It is to be understood, however, that the drawings are designed as an illustration only and not as a definition of the limits of the invention. In the drawings, wherein similar reference characters denote similar elements throughout the several views: FIG. 1 shows a perspective representation of one embodiment of the invention, in which a large cam contour is active; FIG. 2 shows a side view from the right according to FIG. 1 ; FIG. 3 shows a side view from the left according to FIG. 1 ; FIG. 4 shows a detail view of the camshaft with the displaceable cam segment in a switching position in which the small cam contour stands in a functional connection with a gas exchange valve; FIG. 5 shows a detail view of the camshaft with the displaceable cam segment in a switching position in which the large cam contour stands in a functional connection with a gas exchange valve; FIG. 6 shows a perspective representation of the solution according to the invention, during an activated switch between the cam profiles; FIG. 7 shows a perspective representation of the solution according to the invention, in an intermediate position during a switch between the cam profiles; FIG. 8 shows a front view according to FIG. 6 ; FIG. 9 shows a view from above according to FIG. 6 ; FIG. 10 shows a perspective representation of an alternative embodiment of the invention having an alternative gear mechanism to drive the adjustment shaft; FIG. 11 shows a front view according to FIG. 10 ; and FIG. 12 shows a perspective representation of the alternative embodiment of the invention during an activated switch between the cam profiles. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now in detail to the drawings, the valve drive according to one embodiment of the invention is shown in FIG. 1 , for activation of gas exchange valves, and consists of a camshaft 1 driven by a crankshaft of the internal combustion engine, with an adjustment shaft 12 for activating valve stroke switching between two different cam profiles 15 , 16 disposed parallel to it. In this embodiment, adjustment of two valves of a cylinder takes place. An application of the invention can also be used for multiple cylinders. A cam package 2 is mounted in an axially displaceable manner in camshaft 1 , so as to rotate with it. Cam package 2 consists of four cams, of which each set of two adjacent cams have a large cam profile 15 and a small cam profile 16 . Cam package 2 , as shown in FIGS. 4 and 5 , can be structured to be divided in the axial direction, whereby the cam part that consists of base circle profiles 14 is firmly connected with camshaft 1 , and the cam part provided with the cam parts having cam profiles 15 , 16 is displaceable relative to the firmly disposed base circle profiles 14 . FIG. 4 shows a switching position in which each small cam profile 16 stands in a functional connection with the gas exchange valves. In this switching position, small cam profile 16 is above base circle profile 14 . FIG. 5 shows a switching position in which the gas exchange valves are activated by large cam profiles 15 . In order for a precise end switching position to be achieved, a catch element, which is known but not shown, is disposed between the displaceable cam part and camshaft 1 . It is also possible to configure cam package 2 as a component that is connected with camshaft 1 so as to rotate with it, but in an axially displaceable manner on it. In this configuration, it is necessary for each of large cam profile 15 and small cam profile 16 to be provided with a uniform base circle profile 14 . A pin 4 is firmly disposed on axially displaceable cam package 2 , which pin can be brought into engagement with the inside surface of a widening gate groove 20 of an axially displaceable shift gate 3 for displacing cam package 2 . Shift gate 3 partly surrounds camshaft 1 and is provided with a gate groove 20 that widens counter to the direction of rotation of camshaft 1 . Pin 4 passes through gate groove 20 of shift gate 3 during every revolution of camshaft 1 . In this connection, pin 4 is disposed on cam package 2 in such a manner that the axis of pin 4 is disposed in accordance with a switching position that is appropriate for the phase of the base circle 14 , as shown in FIGS. 4 and 5 . A tappet 5 , 23 is firmly connected on both sides of the circumference of shift gate 3 . Tappets 5 , 23 are mounted to be axially displaceable on adjustment shaft 12 . A contour 21 is disposed on the face side of tappet 5 that lies on the outside, and a contour 22 is disposed on the face side of tappet 23 that lies on the outside. The two tappets 5 , 23 are disposed on adjustment shaft 12 , between two adjustment devices 10 , 17 that are disposed on adjustment shaft 12 so as to rotate with it. A guide pin 18 is firmly disposed on adjustment device 10 , which pin connects with contour 21 of tappet 5 . A guide pin 24 is firmly disposed on the adjustment device 17 , which pin connects with contour 22 of tappet 23 . The engagement of guide pin 18 of adjustment device 10 on contour 21 of tappet 5 is disposed offset by 180° relative to the engagement of guide pin 24 of adjustment device 17 on contour 22 of tappet 23 . In this connection, either the axes of guide pins 18 , 24 can lie in one axis direction and contours 21 , 22 are offset by 180° relative to one another, or contours 21 , 22 are disposed identically and guide pins 18 , 24 are offset by 180° relative to one another. A gear wheel 7 is mounted on adjustment shaft 12 so as to rotate with it, but in an axially displaceable manner. In order to displace gear wheel 7 on adjustment shaft 12 counter to the spring pressure of a spring 9 , gear wheel 7 is connected with a drive 6 that moves an adjustment bolt 19 out when activated. After activation of drive 6 , the axially displaceable gear wheel 7 engages into a gear segment 8 that is situated on camshaft 1 . This gear segment 8 extends on camshaft 1 over an angle range of 180° if two gas exchange valves are activated, and is disposed in such a manner that a displacement of tappets 5 , 23 takes place only if pin 4 is situated outside of gate groove 20 . If multiple gas exchange valves of additional cylinders, for example two, are activated by a cam star, gear segment 8 would extend only over an angle range of 90°. Adjustment of cam package 2 for valve stroke switching between two different cam profiles 15 , 16 takes place as follows: FIG. 6 shows a valve drive in which the switching process of engagement of small cam profile 16 with the gas exchange valves to large cam profile 15 was activated by starting up drive 6 . Cam package 2 is in the position shown in FIG. 4 before the switching process is initiated. During the adjustment process, gear wheel 7 is displaced on adjustment shaft 12 by adjustment bolt 19 , so that it engages gear segment 8 situated on camshaft 1 . Displacement of gear wheel 7 only occurs if it has been assured that no engagement of the gear wheel 7 with gear segment 8 can take place during the actual displacement process. Before gear wheel 7 engages gear segment 8 , pin 4 runs through gate groove 20 in shift gate 3 , without touching the inside walls of gate groove 20 while doing so. With the engagement of gear wheel 7 into gear segment 8 , rotation of adjustment shaft 12 by camshaft 1 takes place. FIG. 6 shows the direction of rotation of adjustment shaft 12 and of camshaft 1 and the displacement direction of cam package 2 for this example. FIG. 7 shows an intermediate position of the valve stroke switching by adjustment shaft 12 . Because of the rotation of adjustment shaft 12 , at the same time, adjustment devices 10 , 17 disposed on adjustment shaft 12 so as to rotate with it are rotated, and thus guide pins 18 , 24 firmly disposed on these devices are rotated. Since guide pins 18 , 24 are connected with contours 21 , 22 of tappets 5 , 23 that are each disposed offset by 180°, axial displacement of the two tappets 5 , 23 on adjustment shaft 12 , in the direction of adjustment device 17 , takes place. At the same time, axial displacement of shift gate 3 by tappets 5 , 23 takes place. FIG. 8 shows a side view according to FIG. 7 , and FIG. 9 shows the related top view. In FIG. 8 , the interaction of guide pins 18 , 24 with contour 21 , 22 of the tappets 5 , 23 , respectively, can be clearly seen. In this connection, contours 21 , 22 of tappets 5 , 23 are disposed in such a manner that switching of switch gate 3 in accordance with the phase takes place. After engagement of gear wheel 7 with gear segment 8 has taken its course, adjustment devices 10 , 17 have been rotated so far that guide pin 18 lies against the highest point of contour 21 , and guide pin 24 lies against the lowest point of contour 22 . The displacement of tappets 5 , 23 has been concluded. In order to prevent adjustment shaft 12 from being turned further, a locking device is disposed on adjustment device 10 or 17 . The locking device consists of a spring 11 and a ball 13 , which engages into a corresponding depression disposed in adjustment device 10 or 17 . In FIG. 2 , balls 13 engaged into the depression of adjustment device 10 can be seen. At the same time, drive 6 is deactivated, and gear wheel 7 is moved out of the engagement region of gear segment 8 by the spring force of spring 9 that acts counter to the adjustment direction of drive 6 . In FIG. 1 , this position is shown with gear wheel 7 already pushed back. During displacement of shift gate 3 by tappets 5 , 23 , the pin 4 that is firmly disposed on cam package 2 is situated outside of the region of gate groove 20 that widens counter to the direction of rotation of camshaft 1 , as shown in FIG. 7 . By further rotation of camshaft 1 , pin 4 meets the left inside surface of gate groove 20 at its widest point. As a result of the rotational movement of camshaft 1 , pin 4 migrates along the left inside of gate groove 20 . Because gate groove 20 narrows in the direction of rotation of camshaft 1 , pin 4 and thus the axially displaceable cam package 2 are displaced to the right, until large cam profile 15 lies above the corresponding base circle profile 14 , as shown in FIG. 5 . By means of a locking device disposed between camshaft 1 and the displaceable cam package, cam package 2 is locked in place in the newly achieved switching position. Because of the placement of shift gate 3 and pin 4 , a displacement of cam package 2 and thus valve stroke switching only take place if base circle profile 14 of camshaft 1 is connected to a gas exchange valve. Reverse adjustment takes place analogous to the above description, whereby tappets 5 , 23 are displaced in the direction of adjustment device 10 by guide pins 18 , 24 that connect with contours 21 , 22 . FIGS. 10 , 11 and 12 show a second embodiment of the invention, wherein similar reference characters denote similar elements throughout the several embodiments. Cam package 2 consists of three different cam profiles, the small cam profile 16 , the large cam profile 15 and a middle-sized cam profile 25 which is located between the large 15 and the small cam profile 16 . A valve stroke switching between three different valve strokes caused by the different cam profiles 15 , 16 , 25 can be realized. A tappet 5 , 23 is firmly connected to both sides of the circumference of shift gate 3 . Tappets 5 , 23 are mounted on adjustment shaft 12 and adapted to be axially displaceable on adjustment shaft 12 . Tappets 5 , 23 can be designed integrally as shown in FIG. 10 or can be separate tappets 5 , 23 as shown in FIG. 11 . The tappets 5 , 23 are disposed on adjustment shaft 12 , between two adjustment devices 10 , 17 . Differing from the first embodiment, where guide pins connecting adjustment devices 10 , 17 and tappets, are counter contours 26 , 27 disposed on the face side of the adjustment devices 10 , 17 so as to rotate with them. Counter contour 26 is disposed on the face side of adjustment device 10 opposite of contour 21 disposed on the face side of tappet 5 . Adjustment device 10 and tappet 5 are mechanically linked by contour 21 and counter contour 26 . Analogous to adjustment device 10 is a counter contour 27 disposed on the face side of adjustment device 17 opposite of contour contour 22 , disposed on the face side of tappet 23 . It is a preferred embodiment to link adjustment devices 10 , 17 with tappets 5 , 23 via contours 22 , 23 and counter contours 26 , 27 . An alternative embodiment has a link via guide pins 18 , 24 disposed on adjustment devices 10 , 17 , as described in FIGS. 6 and 7 . Another—not shown—alternative embodiment has guide pins 18 , 24 disposed on tappets 5 , 23 and linked with adjustment devices 10 , 17 where counter contours 26 , 27 are disposed on their face sides. Adjustment shaft 12 is driven by camshaft 1 which can be shiftable linked with the adjustment shaft 12 by a gear mechanism. The gear mechanism consists of a lever system 28 which is disposed on the adjustment shaft 12 so as to rotate with it and a shift cam 29 . The shift cam 29 is in an axially displaceable manner disposed on the camshaft 1 so as to rotate with it. The shift cam 29 can, depending on its axial position on the cam shaft 1 , be linked mechanically with the lever system 28 to drive the adjustment shaft 12 . In another—not shown—embodiment is the lever system 28 axially displaceable disposed on the adjustment shaft 12 and shift cam 29 has a fixed axial position on cam shaft 1 . FIGS. 10 and 11 show the gear mechanism in its inactive state where shift cam 29 and lever system 28 are unengaged. In this inactive state is the adjustment shaft 12 not driven by camshaft 1 in standstill. Tappets 5 and 23 keep their position without rotation of the adjustment devices 10 , 17 . Shift cam 29 can be actuated by actuator 30 which can axially displace the shift cam 29 on camshaft 1 . The possible axial displacement of shift cam 29 is illustrated by a double arrow in FIG. 11 . The axial displacement towards its engaged position with the lever system 28 is caused by actuator 30 whereby the reverse movement into its inactive state is supported by spring 32 . The lever system 28 —shown in FIGS. 10 , 11 and 12 —consists in this embodiment of a system of four interconnected levers arranged around a central hub, whereby each lever supports a pivotably mounted roller 31 supported on the end of each lever. In another embodiment are, instead of the rollers 31 , slide faces (not shown) supposed on the end of each lever. The shift cam 29 is mounted on cam shaft 1 so as to rotate with it, but in an axially displaceable manner. In order to displace shift cam 29 on cam shaft 1 , counter to the spring pressure of spring 32 , shift cam 29 is driven by actuator 30 that drives shift cam 29 axially on camshaft 1 . After activation of actuator 30 , the axially displaceable shift cam 29 engages into a lever of the lever system 28 that is firmly disposed on adjustment shaft 12 . Adjustment of cam package 2 for valve stroke switching between the different cam profiles 16 , 25 and 15 takes place as follows: FIG. 12 shows a valve drive in which the switching process of engagement of medium sized cam profile 25 with the gas exchange valves to large cam profile 15 was activated by starting up actuator 30 . Cam package 2 is in the position before the switching process is initiated. During the adjustment process, shift cam 29 is displaced on adjustment shaft 12 by actuator 30 , so that it engages lever system 28 situated on adjustment shaft 12 . Before shift cam 29 engages lever system 28 , pin 4 runs through gate groove 20 in shift gate 3 , without touching the inside walls of gate groove 20 while doing so. With the engagement of shift cam 29 into lever system 28 , rotation of adjustment shaft 12 by camshaft 1 takes place. Shift gate 3 is positioned by displacement devices 10 , 17 where counter contours 26 , 27 face the contours 21 , 22 of tappets 5 , 23 as described in detail above. The profile of contours 21 , 22 , counter contours 26 , 27 and their position to each other define the axial position of tappets 5 , 23 . The lever system 28 has four lever arms equally spaced around the central hub. The lever system 28 is adapted to rotate adjustment shaft 90° by each rotation of the cam shaft preferably for shifting three different cam profiles. An alternative embodiment of the lever system 28 has two lever arms equally spaced to rotate adjustment shaft 180° by each rotation of the shift cam 29 . The design of the shift element as a shift cam 29 is a preferred embodiment. The shape of the shift element can vary. It has to be adapted to drive the lever system to rotate adjustment shaft. Accordingly, while only a few embodiments of the present invention have been shown and described, it is obvious that many changes and modifications may be made thereunto without departing from the spirit and scope of the invention. 1 camshaft 2 cam package 3 shift gate 4 pin 5 tappet 6 drive 7 gear wheel 8 gear segment 9 spring 10 adjustment device 11 spring 12 adjustment shaft 13 ball 14 base circle profile 15 large cam profile 16 small cam profile 17 adjustment device 18 guide pin 19 adjustment bolt 20 gate groove 21 contour 22 contour 23 tappet 24 guide pin 25 medium-sized cam profile 26 first counter-contour 27 second counter-contour 28 lever system 29 switch cam 30 actuator 31 roller 32 spring
A valve drive for activation of gas exchange valves of internal combustion engines, with which valve stroke switching is accomplished with little effort, a low construction height, and at low switching forces. Incorrect switching and damage to the camshaft during valve stroke switching are avoided, even at high engine speeds of rotation. An adjustment shaft that is rotatable by the camshaft and parallel to the camshaft has two adjustment devices rotatably disposed on it, along with two tappets between the adjustment devices. The tappets are connected with a shift gate for valve switching between two different cam profiles of a cam package that is axially displaceable on the camshaft. The tappets each have a contour that contacts the adjustment devices via a guide pin. A gear wheel engages with a gear segment on the camshaft, via a drive on the adjustment shaft, to rotate the adjustment shaft.
5
BACKGROUND OF THE INVENTION In a typical data communication system, packets containing a variety of data types are transmitted between different nodes of a network, typically in a client-server manner. The packets are transmitted in a stream from a source node to a destination node. The nodes are interconnected via physical connections that conform to a link layer protocol such as HDLC, ATM, and frame relay, for example. These connections may include wireless links, which transmit packets using a radio frequency (RF) medium. The transport layer, however, is typically indifferent to the link layer protocols and whether the link layer is a wireless or wired link. However, wired and wireless links usually exhibit different performance characteristics. For example, wireless links typically exhibit higher error rates, longer latency times, and limited throughput depending on the number of users supported. Many transport layer protocols, however, were developed according to wired link performance expectations, and do not lend themselves to efficient implementation over wireless links. Therefore, connections that include a wireless link may suffer from performance degradation since the transport layer protocols, such as TCP, UDP, and RSTP, are not sensitive to specific performance and behavior characteristics of wireless links. The transport layer protocols are implemented to prevent inaccuracies in the data such as packet loss and transmission errors in the packet. However, certain applications employ data types that are more loss-tolerant and do not need to assure absolute accuracy in the received data stream. For example, data types such as streaming audio and video can tolerate lost packets and bit errors without substantially compromising the output perceived by a user. On the other hand, data types such as an executable file would likely result in unpredictable results if even one bit is inaccurately received. It would be beneficial, therefore, to provide a system and method to determine the application and performance metrics corresponding to a connection, and modify related link control parameters of the wireless link according to a corresponding flow model. The link control parameters may adjust the physical layer characteristics, such as bandwidth, coding levels, and the like, to tolerate packet loss when appropriate. This increases the overall perceived throughput over the wireless link. SUMMARY OF THE INVENTION A system and method for application specific control of wireless link control parameters determines link performance characteristics of a connection, and modifies the link control parameters of the connection according to a corresponding flow model to tolerate packet loss and error when appropriate to increase the overall throughput over the wireless link. Link performance characteristics indicative of a flow of a stream of packets are determined. The link performance characteristics are analyzed to determine a flow model. A transfer model is computed and mapped based on the flow model, and the link control parameters corresponding to the transfer model are then applied to the connection. A packet in an incoming stream of packets received over a connection is examined to determine a corresponding set of link performance characteristics. A particular packet in the stream is usually indicative of other packets in the stream. Accordingly, the stream of packets will tend to conform to the link performance characteristics exhibited by any one of the packets in the stream. Link performance characteristics such as a protocol type, port number, payload type, control bits, and others may be examined. The link performance characteristics are analyzed by a link controller to determine a flow model, such as by matching the link performance characteristics to a flow model table having entries of link performance metrics. In TCP/IP packet systems, for example, a packet has a link performance characteristic called a port number. Certain predetermined port numbers correspond to particular applications. The entries in the flow model table are mapped to a transfer model table. Alternatively, other computations could be performed to compute a transfer model based on the flow model. The transfer model table has entries containing link control parameters. The link control parameters may include, for example, modulation type, ARQ disable flag, coding rate, delay, jitter, minimum suggested bandwidth, average suggested bandwidth, maximum suggested bandwidth, and others. The link control parameters included in each transfer model are selected to provide optimal wireless transmission for the flow model selected. The link controller applies the link control parameters corresponding to the selected transfer model to the connection. In this manner, a wireless link can be optimized by modifying link control parameters according to the type of data carried in the packets based on a loss tolerance corresponding to the data type. BRIEF DESCRIPTION OF THE DRAWINGS The foregoing and other objects, features and advantages of the invention will be apparent from the following more particular description of preferred embodiments of the invention, as illustrated in the accompanying drawings in which like reference characters refer to the same parts throughout the different views. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention. FIG. 1 is a wireless communication system suitable for performing application specific traffic optimization; FIG. 2 is a block diagram of the traffic optimization system; FIG. 3 shows the flow model table; FIG. 4 shows the transfer model table; FIGS. 5 a - 5 c show a flowchart of application specific traffic optimization; FIG. 6 shows an example of application specific traffic optimization; and FIG. 7 shows a diagram of a particular architecture in a base station processor adapted for application specific traffic optimization as described herein. DETAILED DESCRIPTION OF THE INVENTION A description of preferred embodiments of the invention follows. Referring to FIG. 1 , in a computer network 10 , such as a network using the TCP/IP protocol, a logical connection is maintained between a local node or user 12 and a remote node 30 . The user node 12 may, for example be a personal computer (PC) and the remote node 30 may be a file server such as a web server. Data is carried between the user 12 and the remote node 30 by transmitting data in formatted packets, which flow in a stream over the connection. The connection includes both wired links 20 , 24 and a wireless link 26 . The wireless link 26 is maintained by a base station processor 16 and a subscriber access unit 14 , which is in turn connected to the user 12 . The base station processor 16 connects to a public access network such as the Internet 28 via an internetworking gateway 18 over the wired link 24 . A user 12 can therefore maintain wireless connectivity to a remote node 30 via the wireless link 26 provided by the base station processor 16 and the subscriber access unit 14 . The connection between the remote node 30 and the user 12 conforms to a protocol, such as TCP/IP. As described above, TCP/IP was developed for wired networks, and, accordingly, does not lend itself directly to efficient transmissions over the wireless link 26 . Referring to FIG. 2 , a block diagram of the present invention is shown. The base station processor 16 maintains a table of link performance metrics 32 and link control metrics 40 . A link analyzer 36 includes a link controller 38 , a flow model table 34 , and a transfer model table 42 . The set of link performance metrics 32 is defined to enumerate link performance characteristics 44 that can be monitored. The flow model table 34 is defined to specify link performance metrics 32 included in a particular flow model stored in the flow model table 34 . The link controller 38 is operable to analyze link performance characteristics 44 in the packets sent from the remote node 30 over the wired link 24 . The link performance characteristics 44 are analyzed by comparison with flow model entries in the flow model table 34 . The transfer model table 42 is defined from the link control metrics 40 , and stores transfer model entries including one or more link control parameters 46 corresponding to a particular flow model entry in the flow model table 34 . The analysis of the link performance characteristics 44 , described further below, determines a flow model 34 indicative of the stream of packets being transmitted over the link. The link controller 38 computes a corresponding transfer model entry by mapping into the transfer model table 42 . The corresponding transfer model entry in the transfer model table 42 defines one or more link control parameters 46 of the transfer model entry. The link controller 38 then applies the link control parameters 46 to the wireless link 26 via the base station processor 16 . Referring to FIG. 3 , the flow model table 34 is shown having flow model entries 34 a , 34 b , 34 c , . . . 34 n . As described above, each flow model entry 34 n defines link performance metrics 32 corresponding to the data type of a particular stream of packets. In one embodiment, a packet based network associates ports with applications. By examining the port associated with a transmitted packet, the application type can be determined. For example, in a TCP/IP network, certain well known port numbers 48 are predetermined and identified by RFC 1700 promulgated by the Internet Engineering Task Force (IETF). The flow model entry 34 n corresponding to the well known port number 48 determines the application type 50 . The application type 50 is indicative of the loss tolerance of the stream. For example, flow model entry 34 c indicates a streaming audio data type. Streaming audio is generally thought to be more loss-tolerant because lost or erroneous packets would merely be heard as a slight pop or glitch in the output audio signal heard by the user. On the other hand, flow model entry 34 b corresponds to a file transfer, and accordingly, is not tolerant to lost or erroneous packets. The use of the port number as a link performance characteristic as defined herein is exemplary. Other performance characteristics, such as those defined in the flow model table 34 and others, could be employed in computing the transfer model. The flow model is employed to compute a transfer model directed towards optimizing the packet traffic flow on a particular connection. Referring to FIGS. 2 , 3 and 4 , each flow model entry 34 n includes a transfer model index 52 . A transfer model entry 54 n is computed by mapping the transfer model index 52 into the transfer model table 42 to determine the corresponding transfer model entry 54 n . The corresponding transfer model entry 54 n includes link control metrics 40 operable to modify the connection. The link control parameters 46 of the corresponding transfer model entry are applied to the connection. In alternative embodiments, additional computations could be performed to compute the link control parameters. FIGS. 5 a - 5 c illustrate a flowchart of a particular embodiment of message flow, as defined herein, which invokes an IP port number as a link performance characteristic. An IP packet is received from the wired network, as depicted at step 100 . The protocol field is read from the IP header in the packet, as shown at step 102 . It should be noted, however, that other discriminating characteristics of the packets may be examined to construct message flows. In a particular embodiment, the protocol field is examined to determine if the protocol is TCP or UDP, as disclosed at step 104 . If the protocol is not TCP or UDP, then an alternate protocol is handled, as depicted at step 106 , and control continues as described below at step 112 . If the protocol is TCP or UDP, the port numbers are then read from the header, as shown at step 108 . A typical header has both a source and a destination port. Either port may be indicative of an application and hence, a data type. A check is made to determine if there is at least one well-known port, as disclosed at step 110 . If there is not a well-known port, then the default flow model is allowed to persist, as shown at step 112 . Referring back to FIG. 3 , if there is a well-known port, the flow model index 55 corresponding to the port is determined, as disclosed at step 114 , and the corresponding flow model entry 34 n is determined, as disclosed at step 116 . The check may include parsing the flow model table to find a matching well-known port number 48 , and may include other operations directed towards determining a particular flow model entry 34 n. Referring to FIGS. 3 , 4 , and 5 b , the selected flow model 34 n is read to determine the corresponding transfer model index 52 , as depicted at step 118 . The transfer model index 52 is invoked to determine a transfer model entry 54 a , 54 b , 54 c , . . . or 54 n in the flow model table 42 , and the corresponding link control parameters 46 are retrieved, as shown at step 120 . Other computations may also be employed to determine link control parameters, in addition to the transfer model table 42 lookup described above. Packet transmission employing the link control parameters 46 is requested, as disclosed at step 122 , by applying the link control parameters 46 to the connection. Referring to FIG. 5 c , a check is made to determine if a wireless traffic channel is available, as shown at step 124 . If a wireless traffic channel is not available, a wait is performed until a traffic channel becomes available, as depicted at step 126 . When a traffic channel is available, a check is performed to see if the link control parameters can be applied at this time for this packet as shown in step 128 . If the check is successful, the transmitter of the wireless signal is optimized according to the link control parameters established for the connection, as depicted at step 130 . The packet is then sent on the traffic channel, as depicted at step 132 , and a wait is performed for the next packet to be received as depicted at step 134 . Control then reverts to step 100 above as new IP packets are received from the network. Referring to FIGS. 3 , 4 , and 6 , an example of optimal packet flow parameters as defined by the present claims is shown. A packet flow including packet 60 has a port number value of 7070. Accordingly, the flow model index 55 is determined to be F3 stored in flow model table 34 entry 34 c . The transfer model index 52 corresponding to entry 34 c is T 30 . Indexing into the transfer model table 42 with transfer model index T 30 yields transfer model entry 54 c . The corresponding link control parameters for transfer model entry 54 c include ARQ (automatic repeat request) disable 72 value of Y (yes), minimum suggested bandwidth 74 of 28 k , average suggested bandwidth 76 of 32 k , and maximum suggested bandwidth 78 of 40 k . Since the application ID 50 is realaudio, we know that this is a streaming audio connection and therefore is loss tolerant. Accordingly, the ARQ disable may be set to Y because we need not retransmit a lost packet for the reasons described above. Similarly, the suggested bandwidth fields 74 , 76 , and 78 are set to the values corresponding to that application type. On the other hand, the message packet 62 is analyzed to have a port number of 69. Determining the flow model index 55 results in a value of F 2 . Indexing into the flow model table 34 using index 55 of F 2 yields flow model entry 34 b , corresponding to transfer model index T 20 . Computing the corresponding transfer model entry 54 n in the transfer model table 42 indicates that entry 54 b corresponds to T 20 . The corresponding link control parameters 46 for entry 54 b include ARQ disable value of N (no), minimum suggested bandwidth of 48 k , average suggested bandwidth of 64 k , and maximum suggested bandwidth of 80 k . Since flow model entry 34 b indicates a data type of trivial file transfer protocol (tftp), error-free transmission is suggested. Accordingly, the ARQ flag should not be disabled, and the suggested bandwidths are relatively larger, as shown in entry 54 b , as is determined to be most efficient for the corresponding application type. As indicated above, the foregoing example illustrates the use of a port number as a link performance characteristic and the ARQ flag and suggested bandwidth ranges as a link control parameter. In alternate embodiments other variables may also be employed without departing from the invention as claimed below. In particular, the application specific data derivable from a data packet is employed in computing a loss tolerance of the type of data on the connection, and modifying the connection to specific, optimal values for the particular data type. For example, the delay 80 link control parameter is used to specify a maximum delay which may occur between transmissions to avoid starving the user with real-time information, such as audio and video. Similarly, jitter 82 refers to the maximum variance between transmissions which should be permitted which still allows the user to maintain the incoming stream. FIG. 7 shows a particular embodiment of base station processor 16 architecture for implementing application specific traffic optimization. This architecture is operable for wireless channel allocation and message transmission as described in co-pending U.S. patent application entitled “Dynamic Bandwidth Allocation for Multiple Access Communication Using Session Queues,” Attorney docket No. 2479.2073-000, which is a continuation-in-part of a prior U.S. patent application Ser. No. 09/088,527 filed Jun. 1, 1998, entitled “Dynamic Bandwidth Allocation for Multiple Access Communications Using Buffer Urgency Factor.” The entire teachings of the above applications are incorporated herein by reference. Referring to FIG. 7 , at the base station 16 , incoming traffic is separated into individual traffic flows destined for separate subscriber access units 14 generally (FIG. 1 ). The traffic flows may be separated by various methods, such as by examining a destination address field in the TCP/IP header. The individual traffic flows are delivered first to transport modules 401 - 1 , 401 - 2 ,. . . , 401 -n with a transport module 401 corresponding to each of the intended subscriber units 14 . A given transport module 401 is the first step in a chain of processing steps that is performed on the data intended for each subscriber unit 14 . This processing chain includes not only the functionality implemented by the transport module 401 but also a number of session queues 410 , a session multiplexer 420 , and transmission buffers 440 . The outputs of the various transmission buffers 440 - 1 , 440 - 2 , . . . , 440 -n are then assembled by a transmit processor 450 that formats the data for transmission over the forward radio links. Returning attention now to the top of the FIG. 7 again, each transport module 401 has the responsibility of either monitoring the traffic flow in such a way that it stores data belonging to different transport layer sessions in specific ones of the session queues 410 associated with that transport module 401 . For example, transport module 401 - 1 assigned to handle data intended to be routed to subscriber unit 14 has associated with it a number, m, of session queues 410 - 1 - 1 , 410 - 1 - 2 , . . . , 410 - 1 -m. In the preferred embodiment, a given session may be characterized by a particular transport protocol in use. For example, in a session oriented transport protocol, a session queue 410 is assigned to each session. Such session transport oriented protocols include, for example, Transmission Control Protocol. In sessionless transport protocols, a session queue 410 is preferably assigned to each stream. Such sessionless protocols may for example be the Universal Datagram Protocol (UDP). Thus traffic destined for a particular subscriber unit 14 is not simply routed to the subscriber unit 14 . First, traffic of different types from the perspective of the transport layer are first routed to individual session queues 410 - 1 - 1 , 410 - 1 - 2 , . . . , 410 - 1 -m, associated with that particular connection. In accordance with the system as defined above, traffic indicating a new connection is analyzed to determine link performance characteristics 44 for the messages received on that connection. The link performance characteristics 44 are analyzed to determine a flow model index 55 , as described above with respect to FIG. 3 . The flow model is then used to compute a transfer model entry 54 as described above with respect to FIG. 4 . The transport module 401 invokes the link performance characteristics 46 corresponding to the computed transfer model entry 54 , and applies them to the session queue 410 -n-m for this connection. Another key function performed by the transport module 401 - 1 is to assign priorities to the individual queues 410 - 1 associated with it. It will later be understood that depending upon the bandwidth available to a particular subscriber unit 14 , traffic of higher priority will be delivered to the transmission buffer 440 - 1 before those of lower priority, as determined by the transfer model and the associated link control parameters 46 in the transfer model table 42 . This may include traffic that is not session oriented, for example, real time traffic or streaming protocols that may be carrying voice and/or video information. More particularly, the transport module 401 - 1 reports the priorities of each of the individual session queues 410 - 1 to its associated session multiplexer 420 . Traffic of higher priority will be selected by the session multiplexer 420 for loading into the transmit buffer 440 - 1 for loading traffic of lower priority, in general as determined by the link control parameters 46 from the entries 54 in the transfer model table 42 . Those skilled in the art should readily appreciate that the programs defining the operations and methods defined herein are deliverable to a subscriber access unit and to a base station processor in many forms, including but not limited to a) information permanently stored on non-writeable storage media such as ROM devices, b) information alterably stored on writeable storage media such as floppy disks, magnetic tapes, CDs, RAM devices, and other magnetic and optical media, or c) information conveyed to a computer through communication media, for example using baseband signaling or broadband signaling techniques, as in an electronic network such as the Internet or telephone modem lines. The operations and methods may be implemented in a software executable by a processor or as a set of instructions embedded in a carrier wave. Alternatively, the operations and methods may be embodied in whole or in part using hardware components, such as Application Specific Integrated Circuits (ASICs), state machines, controllers or other hardware components or devices, or a combination of hardware, software, and firmware components. While the system and method for application specific traffic optimization have been particularly shown and described with references to embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the scope of the invention encompassed by the appended claims. Accordingly, the present invention is not intended to be limited except by the following claims.
A packet data system such as a TCP/IP network transmits packets containing a variety of data types along links in the network. Packets are transmitted in a stream between nodes interconnected by the links, which conform to a transport layer protocol such as TCP, UDP, and RSTP, and include wireless links, which transmit packets using a radio frequency (RF) medium. Typical protocols, however, are usually developed to optimize throughput and minimize data error and loss over wired links, and do not lend themselves well to a wireless link. By examining the data in a packet, performance characteristics such as a port number are determined. The performance characteristics indicate the application type, and therefore, the data type, of the packets carried on the connection. Since certain data types, such as streaming audio and video, are more loss tolerant, determination of the data type is used to compute link control parameters for the wireless link that are optimal to the type of data being transmitted over the link.
7
FIELD OF INVENTION The present invention relates to arc lamps, and more particularly, to cooling an arc lamp. BACKGROUND In optical systems involving the generation and controlled radiation of long or continuous pulses of light, such as spectroscopy, or solar simulation, where high intensity, color correct illumination of sensitive working areas is required, such as in fiber optics illumination devices, it is advantageous to have a light source capable of producing the highest possible light flux density. Products utilized in such applications include short arc inert gas lamps, which may also be referred to as arc lamps. At least one short arc lamp includes a sealed chamber containing a gas pressurized to several atmospheres, and an opposed anode and cathode defining an arc gap. A window provides for the transmission of the generated light, and a reflector body may be positioned surrounding the arc gap. During operation of an arc lamp, the anode and the cathode generate a significant amount of heat. The anode and the cathode are inside the sealed chamber of the arc lamp. As a result, the reflector body is also subjected to high heat during operation of the arc lamp. The operating power of the arc lamp may be limited by the reflector body temperatures. A lower temperature reflector body allows for a higher operating lamp power. Furthermore, the reflector body may crack, and the lamp will fail, when operated at high temperatures over a long period of time. One existing technique to aid cooling of the reflector body is to directly couple a heat sink to the underside of the reflector body. However, the above technique is unsatisfactory because of the lack of adequate surface area in contact with the heat sink to dissipate heat from the reflector body to the heat sink. Another existing technique is to add a copper band along the underside of the cathode heat sink to help cool off the reflector body. Alternatively, a thermal heat transfer pad is coupled to one end of the reflector body that is near the anode to facilitate heat dissipation from the reflector body. However, these techniques also suffer from the problem of inadequate surface area in contact with the heat sink to dissipate heat from the reflector body to the heat sink. SUMMARY A method and an apparatus for cooling an arc lamp are described. In one embodiment, the arc lamp assembly includes an arc lamp, a first heat sink coupled to an anode of the arc lamp, and a thermally conductive ring surrounding a first part of the outer surface of a reflector body of the arc lamp to thermally couple the reflector body to the first heat sink. Other features of the present invention will be apparent from the accompanying drawings and from the detailed description that follows. BRIEF DESCRIPTION OF THE DRAWINGS The present invention will be understood more fully from the detailed description that follows and from the accompanying drawings, which however, should not be taken to limit the appended claims to the specific embodiments shown, but are for explanation and understanding only. FIG. 1 shows one embodiment of an arc lamp assembly. FIG. 2 shows a cross-section view of an embodiment of an arc lamp assembly. FIG. 3 shows an alternate embodiment of an arc lamp assembly. FIG. 4 shows a cross-section view of one embodiment of an arc lamp assembly. DETAILED DESCRIPTION In the following description, numerous specific details are set forth. However, it is understood that embodiments of the invention may be practiced without these specific details. In other instances, well-known components, structures, and techniques have not been shown in detail in order not to obscure the understanding of this description. FIG. 1 illustrates one embodiment of an arc lamp assembly 100 with various components separated from each other for the purpose of illustration. An assembled view 199 of the various components is shown in the bottom right corner of FIG. 1 . The arc lamp assembly 100 includes a cathode heat sink 110 , an arc lamp 120 , an electrical insulator ring 130 , a wave washer spring 140 , a retainer ring 150 , a thermally conductive ring 160 , and an anode heat sink 170 . In addition to the above components, the arc lamp assembly 100 includes a cathode and an anode (not shown) mounted inside the arc lamp 120 . The cathode is mounted near the end of the arc lamp 120 closer to the cathode heat sink 110 while the anode is mounted near the opposite end of the arc lamp 120 . The thermally conductive ring 160 may be pre-loaded to the arc lamp 120 using the wave washer spring 140 . To hold the thermally conductive ring 160 in place to assure good contact between the thermally conductive ring 160 and the arc lamp 120 , a retainer ring 150 may be coupled to the outer surface of thermally conductive ring 160 . In one embodiment, the thermally conductive ring 160 is made of copper. Detail of the way heat is dissipated from the arc lamp 120 is discussed below with reference to FIG. 2 . To prevent arcing from the thermally conductive ring 160 to the cathode heat sink 110 of the arc lamp, the electrical insulator ring 130 is coupled to the reflector body 120 to surround the outer surface of the arc lamp 120 and in between the cathode heat sink 110 and the wave washer spring 140 . In one embodiment, the electrical insulator ring 130 is made of glass silicon. Alternatively, the electrical insulator ring 130 is made of Teflon or an equivalent material that is electrically non-conductive and has a high thermal conductivity (e.g., up to 1800° C.) that is capable of sustaining operating temperature of the arc lamp. FIG. 2 shows a cross-sectional view of one embodiment of an arc lamp assembly 200 . For the purpose of illustration, only the right half of the cross-section is shown, which provides sufficient details to one of ordinary skill in the art to practice the embodiment of the present invention. The arc lamp assembly 200 includes a cathode heat sink 210 , a cathode 215 , an anode heat sink 270 , an anode 275 , a reflector body 220 , an electrically insulator ring 230 , a spring 240 , a thermally conductive ring 260 , and a retainer ring 250 . The anode 275 is mounted at one end of the reflector body 220 and the cathode 215 is mounted by a strut 217 near the opposite end of the reflector body 220 . The outer surface of the reflector body 220 is surrounded by the thermally conductive ring 260 . In one embodiment, the thermally conductive ring 260 is pre-loaded by the spring 240 . Furthermore, to ensure good contact between the thermally conductive ring 260 and the outer surface of the reflector body 220 , the retainer ring 250 is coupled to the outer surface of the thermally conductive ring 260 to provide radial compression onto the thermally conductive ring 260 . In one embodiment, the thermally conductive ring 260 is made of metallic material, such as copper. Alternatively, the thermally conductive ring 260 may be made of non-metallic material, such as aluminum nitride. During operation of the arc lamp assembly 200 , the reflector body 220 is subjected to high heat generated by the anode 275 and the cathode 215 . To cool off the reflector body 220 , the thermally conductive ring 260 allows a heat flow 201 to travel from the reflector body 220 to the anode heat sink 270 , which dissipates the heat. Since the thermally conductive ring 260 provides a large surface area in contact with the reflector body 220 , the rate of heat flow through the thermally conductive ring 260 may be increased. To further facilitate the heat flow 201 , one or more heat transfer pads or compounds 252 may be added at the locations between the thermally conductive ring 260 and the reflector body 220 or between the thermally conductive ring 260 and the anode heat sink 270 . To prevent arcing from the thermally conductive ring 260 to the metal ring of the arc lamp, the electrical insulator ring 230 may be coupled between the spring 240 and the cathode heat sink 210 . In one embodiment, the electrical insulator ring 230 is bonded to the outer surface 237 of the reflector body 220 . FIG. 3 illustrates an alternate embodiment of an arc lamp. Various components of the arc lamp assembly 300 in FIG. 3 are separated from each other for the purpose of illustration. The arc lamp assembly 300 includes a cathode heat sink 310 , an arc lamp 320 , a retainer ring 350 , a thermally conductive and electrically insulative ring 360 , and an anode heat sink 370 . The arc lamp assembly 300 further includes an anode and a cathode (not shown) mounted inside the arc lamp 320 . When assembled, the thermally conductive and electrically insulative ring 360 is coupled to the outer surface of the arc lamp 320 , surrounding the arc lamp 320 . To improve contact between the arc lamp 320 and the thermally conductive and electrically insulative ring 360 , the retainer ring 350 may be coupled to the outer surface of the thermally conductive and electrically insulative ring 360 to provide radial compression onto the thermally conductive and electrically insulative ring 360 . In one embodiment, the thermally conductive and electrically insulative ring 360 is made of aluminum nitride. More detail on the operation of the arc lamp assembly 300 is discussed below. FIG. 4 shows a cross-sectional view of one embodiment of an arc lamp assembly. For the purpose of illustration, only the right half of the cross-section is shown, which provides sufficient details to one of ordinary skill in the art to practice the embodiment of the present invention. The arc lamp assembly 400 includes a cathode heat sink 410 , a cathode 415 , an anode heat sink 470 , an anode 475 , a reflector body 420 , a thermally conductive and electrically insulative ring 460 , and a retainer ring 450 . The thermally conductive and electrically insulative ring 460 may be made of aluminum nitride. The inner surface of the thermally conductive and electrically insulative ring 460 is coupled to the outer surface of the reflector body 420 to surround the reflector body 420 . A first end of the thermally conductive and electrically insulative ring 460 is coupled to the cathode heat sink 410 and the second end of the thermally conductive and electrically insulative ring 460 is coupled to the anode heat sink 470 . By surrounding the outer surface of the reflector body 420 , the ring 460 provides more surface area for heat transfer to improve cooling of the reflector body 420 . Heat may flow from the reflector body 420 through the ring 460 to either the cathode heat sink 410 and/or the anode heat sink 470 as indicated by the arrows 403 and 401 , respectively. In one embodiment, the retainer ring 450 is coupled to the outer surface of the thermally conductive and electrically insulative ring 460 to provide radial compression onto the thermally conductive and electrically insulative ring 460 in order to hold the thermally conductive and electrically insulative ring 460 in position and to improve the contact between the thermally conductive and electrically insulative ring 460 and the reflector body 420 . Furthermore, one or more heat transfer pads or compounds may be coupled to the surfaces of the thermally conductive and electrically insulative ring 460 that are adjacent to the reflector body 420 or one of the heat sinks 410 and 470 . Some exemplary positions at which the heat transfer pads or compounds may be coupled to are indicated by the reference numerals 452 and 454 in FIG. 4 . By increasing the surface area of the thermally conductive and electrically insulative ring 460 , via which the reflector body 420 may dissipate heat to the heat sinks 410 and/or 470 , the reflector body 420 may be cooled faster. With a faster cooling rate, the reflector body 420 may operate at higher temperatures, and hence, the power of the arc lamp 400 may be increased without risking increasing the likelihood of cracking the reflector body 420 . In an exemplary embodiment, the power of the arc lamp assembly 400 may be increased by approximately 30%, such as, for example, from approximately 300 watts to about 400 watts. The foregoing discussion merely describes some exemplary embodiments of the present invention. One skilled in the art will readily recognize from such discussion, the accompanying drawings and the claims that various modifications can be made without departing from the spirit and scope of the invention.
A method and an apparatus for cooling an arc lamp have been disclosed. In one embodiment, the arc lamp assembly includes an arc lamp, a first heat sink coupled to an anode of the arc lamp, and a thermally conductive ring surrounding a first part of the outer surface of a reflector body of the arc lamp to thermally couple the reflector body to the first heat sink. Other embodiments have been described and claimed.
7
REFERENCE TO RELATED APPLICATION The present application claims the benefit of, and incorporates by reference, the commonly owned, co-pending U.S. provisional application Ser. No. 60/047,383, filed May 22,1997. BACKGROUND OF THE INVENTION The present invention concerns methods and systems for treatment of restenosis in body lumens such as blood vessels and, in particular, the treatment of in-stent restenosis. Endoluminal stents are commonly used to treat obstructed or weakened body lumens, such as blood vessels and other vascular lumens. Numerous stents exist for this purpose, including those made of metals, fibers and other biocompatible materials. In general, the stent is either formed outside the body and then guided into place (e.g., adjacent to an obstruction) through a body lumen, or is positioned into place prior to formation and is then expanded and/or formed in situ within the body lumen. Once deployed, the stent can remain in the body lumen where it will maintain the patency of the lumen and/or support the walls of the lumen which surround it. One factor impeding the success of stent technology in endoluminal treatments is the frequent occurrence of in-stent restenosis, characterized by proliferation and migration of smooth muscle cells within and/or adjacent to the implanted stent, causing reclosure or blockage of the body lumen. While the reasons for such smooth muscle cell proliferation following stent implantation are not entirely clear, it is believed that positioning of the stent within the body lumen may somehow irritate or damage the surrounding lumen walls and activate medial smooth muscle cells lining the walls. Current methods for treating endoluminal restenosis, such as that which occur within or around a stent, generally consist of invasive procedures which physically remove atherosclerotic plaque by, for example, shaving or ablating the plaque, or by implanting a second stent. However, these procedures can cause further damage to the area of treatment and/or initiate further smooth muscle cell proliferation. Accordingly, it is an object of the present invention to provide a substantially non-invasive method of treating in-stent restenosis by applying radiation to the smooth muscle cells which have grown within or around a stent implant in a manner that does not substantially damage the surrounding lumen wall or the stent itself, while resulting in a reduction of smooth muscle cell mass. SUMMARY OF THE INVENTION Methods and systems are disclosed for treating in-stent restenosis using radiation having a wavelength sufficient to kill or promote cellular death (e.g., through programmed cell death), or otherwise remove smooth muscle cells which have proliferated, or which might otherwise proliferate, in the proximity of (i.e., within, around or adjacent to) a stent within a body lumen, causing (or potentially causing) at least partial blockage of the lumen. Devices are disclosed for providing such therapeutic radiation at the stent with or without concurrent mechanical (e.g. balloon dilation) angioplasty. Treatment methods are also disclosed which include irradiating smooth muscle cells in the region of the stenosis with non-ablative, cytotoxic radiation, such as UV radiation. A cytotoxic, photoactivatable chromophore may also be delivered to the treatment site prior to irradiation. The methods and systems can be used prophylactically or to treat in-stent restenosis after blockage has occurred without further damage to surrounding tissue. In-stent restenosis can be treated effectively and with minimal tissue damage using cytotoxic, nonablative radiation, such as UV radiation. The radiation kills or otherwise inactivates smooth muscle cells which have proliferated or are susceptible to proliferation within and/or adjacent to a stent in a body lumen, causing the cells to retract from the stenosed region. The radiation is preferably delivered to the area around (e.g., within or adjacent to) the stent via an optical fiber or other waveguide incorporated, for example, into a percutaneous catheter. The term “in-stent restenosis,” as used herein, includes partial or complete blockage of a body lumen in an area of stent implantation due in whole or in part to proliferation of medial smooth muscle cells within or around (e.g., adjacent to) the stent. The term “cell overgrowth” as used herein is intended to describe any condition involving the proliferation of cells in proximity to a stent. The term “body lumen,” as used herein, includes any body lumen capable of containing a tent, such as vascular, urological, biliary, esophageal, reproductive, endobronchial, gastrointestinal, and prostatic lumens. The term “non-ablative, cytotoxic radiation,” as used herein, means radiation which directly or indirectly (e.g., by apoptosis) kills or otherwise causes the removal of smooth muscle cells in a stenosed region, resulting in a reduction in tissue mass and/or an increase in the diameter of the lumen, without the use of heat ablation. In one embodiment of the invention, the cytotoxic, non-ablative radiation is ultraviolet (UV) radiation having a wavelength of less than about 280 nanometers, down to about 240 nanometers (due to the limited transmission efficiency of glass optical fibers at lower wavelengths). The effect of UV radiation having this wavelength range, commonly known as UV “C” radiation, at the doses necessary to penetrate the build up of smooth muscle cell mass, causes direct cellular death of most cells and can cause programmed cell death in other cells, resulting in a reduction in cell mass without heating or damaging the surrounding tissue. In another embodiment of the invention, the cytotoxic, non-ablative radiation has a longer wavelength, such as UV “A” or “B” radiation in the wavelength range of about 280 nanometers to 400 nanometers, or visible radiation having a wavelength of about 400 to 700 nanometers, or infrared radiation from about 700 nanometers to 2.6 micrometers, and is used in conjunction with a photoactivatable, cytotoxic chromophore which is activated upon exposure to light at some or more of these wavelengths. The term “photoactivatable, cytotoxic chromophore,” as used herein, encompasses chromophores capable of being absorbed by mammalian tissues and being activated upon exposure to light so cells of the tissue die or cease to proliferate. In the present invention, the photoactivatable chromophore is delivered to tissue which has increased in mass (e.g., due to smooth muscle cell proliferation) within or around a stent and is causing restenosis of the lumen supported by the stent. The tissue is then exposed to radiation of a sufficient wavelength to activate the chromophore. Once activated by the light, the chromophore causes direct programmed death (apoptosis) thereby decreasing the number of cells and the mass of the tissue. Suitable chromophores for use in the invention are generally selected for absorption of light that is deliverable from common radiation sources (e.g. UV light ranging from 240-400 nanometers, or visible light having wavelengths of 400 nanometers or longer). For example, photoactivatable psoralens and hematoporphyrins can be administered systemically or locally to the stenosed region prior to irradiation, thereby rendering smooth muscle cells in the region more susceptible to radiation. Other suitable chromophores are well known in the art and include those which are photoactivated upon irradiation with either long-wave UV light (PUVA) (See, e.g., U.S. Pat. No. 5,116,864 (Mar. et al.) or with visible light (see, e.g., U.S. Pat. No. 5,514,707 (Deckelbaum et al.), the disclosures of which are incorporated herein by reference.) Various radiation sources can be use in accordance with the present invention to deliver non-ablative, cytotoxic radiation to a stenosed region within or around a stent. Generally, the radiation is delivered via a laser catheter carrying a fiber optic waveguide. Either pulsed or continuous wave (“CW”) lasers can be used in the present invention, and the lasant medium can be gaseous, liquid or solid state. The laser can be a pulsed excimer laser, such as a KrF laser. Alternatively, rare earth-doped solid state lasers, ruby lasers and Nd:YAG lasers can be operated directly or in conjunction with frequency modification means to produce an output beam at the appropriate radiation wavelength (e.g., UV wavelength). Alternatively, a UV flash lamp can be employed. In one embodiment, a laser system which operates at about 266 nanometers is used to maximize the cytotoxic effect of the radiation. This may be achieved using an output beam wavelength of about 266 nanometers or, alternatively, using an output beam wavelength of about 1064 nanometers, such as a common Nd:YAG laser, in conjunction with two doubling crystals to yield a radiation output of about 266 nanometers. Similarly, a Nd:YLF laser operating at about 1047 nanometers can be used in conjunction with two frequency doubling crystals. Other useful UV radiation sources include, for example, Argon ion lasers emitting UV light at about 257 or 275 nanometers and KrF excimer lasers emitting light at about 248 nanometers. In another embodiment of the invention, the cytotoxic, non-ablative radiation is provided by a “low energy” radiation source. The term “low energy” is used herein to describe both laser and non-coherent radiation systems having an energy output of less than about 5 J/cm 2 per pulse for pulsed lasers, or a total dose of less than about 1000 J/cm 2 , more preferably less than 100 J/cm 2 , for continuous wave lasers or non-coherent radiation sources. In general, when using conventional percutaneous catheters to deliver radiation, at least one optical fiber or waveguide is incorporated into the catheter for transmission and delivery of the radiation to the lesion (i.e., stenosed) site. For example, an optical fiber having about a 200 micron diameter core may be used. The catheter tip can also contain focusing optics or diffusive elements for use in directing the radiation emitted from the catheter within an artery. The therapeutic radiation can be provided by a single laser or a plurality of lasers operating in tandem to deliver cytotoxic, nonablative laser radiation. Catheter systems useful in connection with the present invention may also be equipped with a translucent (light-conducting) balloon which encompasses the optical fiber(s) or other energy conducting means. One example of such an apparatus is disclosed in commonly-owned, U.S. Pat. No. 5,620,438 issued to Amplatz et al. on Apr. 15, 1997 and incorporated herein by reference. Once the catheter is guided into place within or adjacent to an area of restenosis associated with a stent, the balloon is inflated to dilate the surrounding tissue. Light is then delivered into the balloon via the optical fiber(s) and is transmitted through the balloon onto the surrounding tissue of the lumen walls. The balloon is preferably large enough in diameter to completely cover (i.e., come in contact with all portions of) the stenosed region. Preferably, the balloon is at least sized such upon inflation, it extends beyond the length of the stent by a distance sufficient to dilate any blockage within the stent. The light source (or sources) can likewise be chosen to extend beyond the stent by a sufficient distance to ensure treatment of the entire restenosis. In one illustrated embodiment, a 30 mm length balloon is inflated within a 20 mm stent overgrown (infiltrated) with smooth muscle cells. The balloon is inflated so that the entire interior of the stent is dilated and the distal ends of the balloon emerge from the stent. The method of the present invention can be used to treat in-stent restenosis which has already occurred within or adjacent to a stent in a body lumen. The method provides the advantage of being substantially non-invasive and non-injurious compared to methods which physically remove or ablate endoluminal lesions. The invention will next be described in connection with certain illustrated embodiments. However, it should be clear that various changes and modifications can be made by those skilled in the art without departing from the spirit or scope of the invention. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a partially cross-sectioned side view of a surgical instrument useful in accordance with the present invention; FIG. 2 is cross-sectional front view taken along the line 2 — 2 in FIG. 1 : FIG. 3 is a schematic cross-sectional illustration of a balloon catheter device according to the present invention positioned within a stent exhibiting partial restenosis; and FIG. 4 is a schematic illustration of the balloon catheter device shown in FIG. 3 in operation. DETAILED DESCRIPTION FIG. 1 illustrates an instrument 10 especially designed for delivering radiant energy to an in-stent restenosis site within the vascular system of a patient. It is seen to comprise a elongated, flexible tubular catheter body 12 having an outer diameter of about 0.040 in. and a wall thickness of approximately 0.005 in. The catheter body is preferably extruded from polyethylene plastic and, as is illustrated in the cross-sectional front view of FIG. 2, has at least first and second lumens 14 and 16 , respectively. Appropriately joined to the exterior surface of the tubular body 12 at its distal end portion is an expansion element 18 , such as a balloon, which can circumferentially bonded at its ends 20 and 22 to the tube 12 at spaced apart locations. The expansion element 18 can be mechanically expandable but is preferably formed from polyethylene or polytetrafluoroethylene structure which can be expanded by inflation. These plastics exhibiting high radiant energy transmissivity in the UV light portion of the spectrum. The length of the expansion element is preferably chose to be at least as great or greater than the stent to be treated. The expansion element 18 may typically be anywhere from 20 to 30 mm in length and can span one or more ports 24 formed through the first lumen 14 (FIG. 2 ), i.e., the inflation lumen. It is also found expedient to locate radioopaque marker bands 26 and 28 on opposite ends of the expander member relative to a lesion to be treated under fluoroscopy. Disposed at the proximal end of the catheter body 12 is a molded plastic hub member 30 which is generally tubular and which has a Touchy-Borst type compression fitting 32 disposed near its proximal end. The hub 30 also includes first and second ports 34 and 36 having Luer fitting for connection to liquid supply tubes (not shown). The port 34 is in fluid communication with the inflation lumen 14 and when a fluid, such as normal saline, is injected under pressure into that port, it flows through the lumen 14 and the ports 24 in the catheter to affect inflation of the expansion element 18 . The port 36 is in fluid communication with the lumen 16 catheter. By pumping saline with a roller pump at a low rate of about 2-4 cubic cms per minute into the port 36 , the flow prevents blood from entering the distal end 38 of the catheter. Extending through the compression fitting 32 , the tubular hub 30 and through the second lumen 16 of the instrument 10 is an elongated, flexible, radiant energy-transmissive fiber assembly 40 . Where the radiation source to be employed is a source of UV light, the radiant energy transmissive fiber may comprise a core member 42 including a quartz fiber 44 covered by a Teflon jacket 46 . The wall thickness of the jacket may be approximately 0.003 in. The quartz fiber has a distal end 48 and the jacket 46 extends in the distal direction beyond the end 48 of the fiber for a distance of about 6 mm and forms a radiant energy diffusing and emitting element 50 . A radioopaque plug 52 is fitted into the distal end of the element 50 . Starting a predetermined distance proximal of the distal plug 52 and extending proximally through the compression fitting 32 of the hub 30 is an outer tubular reinforcing member 54 , which preferably comprises a stainless steel tube whose O.D. is about 0.014 in. The stainless steel reinforcing member 54 tightly surrounds the jacket 46 of the quartz fiber 44 and because of its relative rigidity compared to that of the quartz fiber 44 , it permits the radiant energy transmissive fiber assembly 40 to be pushed longitudinally through the lumen 16 of the catheter body 12 when a force is applied at the proximal end of the radiant energy transmissive fiber assembly. The length of the core 42 that extends beyond the distal terminus of the reinforcing member 54 may be approximately 13 in. and, as such, the assembly 40 exhibits sufficient “pushability” and “torqueability” to permit the unreinforced portion to transverse the lumen 16 of the tubular body 12 . If gamma radiation is to be delivered to the affected area of the blood vessel, a suitable source of gamma radiation, such as cobalt 60 particles may be embedded in the plastic at the distal end of an elongated flexible fiber. With continued reference to FIG. 1, there is shown attached to the portion of the radiant energy-transmissive fiber assembly 40 extending proximally beyond the compression fitting 32 and adjustable stop member 56 . The stop assembly 40 to a desired position and then locked in place by rotating the knurled grip 58 , thereby effectively establishing a predetermined travel distance between the stop member 56 and the proximal end of the hub 30 . This also defines the extent of displacement of the diffusing element 50 in the distal direction. The radiant energy-transmissive fiber assembly 40 extends proximally beyond the stop member 56 and passes through a strain relief member 60 , terminating in a standard connector 62 . Connector 62 is adapted to couple with the output of a radiant energy source (not shown). The radiant energy source is preferably a pulsed or continuous wave laser capable of producing an output beam at an appropriate UV wavelength. It has been found that a wavelength in the range of from 240 nm to 280 nm covers the range exhibiting efficacy in inhibiting smooth muscle tissue growth. The UV light emanating from the laser source passes through the quartz fiber 44 to its distal end 48 . The Teflon diffusing element 50 , comprising the jacket extension, is found to uniformly diffuse the UV light exiting the end of the quartz fiber. Because the tubular body 12 and the expander member 18 are fabricated from a highly UV light transmissive material (polyethylene), the UV light emanating from the diffuser 50 causes a radial band of light, approximately the length of the jacket extension, to radiate out through the expander member to impinge upon the intimal tissue. By controlling the displacement of the fiber in the axial direction, the emanating band of UV radiation can be made to traverse the entire length of the expander member continuously or in discrete steps to thereby expose the adjacent vessel wall to the radiant energy. Various radiation diffusive tip assemblies can also be employed in conjunction with the present invention, such the diffuser designs disclosed in International Patent Application Pub. No. WO 96/07451 published Mar. 14, 1996 and incorporated herein by reference. It is possible, of course, also to rotate the radiant energy transmissive fiber assembly within the lumen of the catheter when and if the radiation pattern exiting the diffusing member is not annularly symmetrical. The methods of the present invention can be practiced as shown in FIG. 3, where radiation delivered via a catheter instrument (such as instrument 10 described above in FIGS. 1-2 or a similar balloon catheter instrument 12 adapted to include a radiation-emitter). In use, the instrument 10 serves to treat restenosis 3 which has occurred (e.g., due to smooth muscle cell overgrowth) within and adjacent to a stent 4 situated in a region of a body lumen 7 . The instrument 10 includes an elongated flexible tube 12 with an expandable balloon 18 attached at the distal end. The overall system can further include a radiation source 70 , a fluid source 72 (for balloon inflation and/or blood stream perfusion), a diagnostic detector 74 , and a controller 76 (e.g., a microprocessor which controls the other elements by either preprogrammed instructions or real-time diagnostic or user-generated instructions). The catheter also includes at least one optical fiber assembly 40 for delivering radiation into the balloon 18 . At its proximal end, the optical fiber assembly is connected to a source of radiation 70 , such as a laser. The instrument 10 can further include one or more sensors 78 (e.g., ultrasonic probes or electrical mapping electrodes) which are electronically or optically coupled to the detector 74 to provide data on the progress of the dilation, irradiation or other conditions in-situ. Suitable lasers for delivering radiation are described, for example, in U.S. Pat. No. 5,053,033, the disclosure of which is incorporated by reference herein. The optical fiber 40 extends through the catheter body 12 into the balloon 18 attached to the distal end. The tip of the fiber is preferably designed to diffuse light outwardly through the balloon, for example, by tapering the end or by using a diffusive radio-opaque material, as is well known in the art. The radiation source 70 can be a UV light source which delivers light having a wavelength ranging from about 200 to about 400 nanometers, more preferably from about 240 to about 370 nanometers. The radiation can be provided by a variety of sources, including non-coherent UV light sources and excimer laser sources (e.g., a KrF excimer laser operating at 248 nanometers or an Argon ion laser at 257 or 275 nanometers). Alternatively, the source can be a visible light source which delivers light having a wavelength greater than 400 nanometers, preferably around 420 nanometers. The energy of the UV radiation can be about 5 J/cm 2 per pulse or less for pulsed lasers, or a total dose of about 1000 J/cm 2 or less. The power density of the radiation is preferably less than 5 watts per square centimeter, more preferably less than 2 watts per square centimeter. The use of the catheter system shown in FIG. 3 is further schematically illustrated in FIG. 4 . The catheter 12 is first guided into place adjacent to an area of smooth muscle cell overgrowth within a stent using, for example, a conventional guidewire 80 . The inflatable balloon 18 is then expanded which applies pressure against the surrounding lumen wall 7 . Expansion of the inflatable balloon 18 serves to dilate the obstructed area and increase the uniformity of light distribution onto the surrounding tissue. Following expansion of the inflatable balloon 18 , radiation from the radiation source 70 is delivered via one or more assemblies of optical fibers 40 which extend through the terminal end of the device into the inflatable balloon 18 . In one embodiment, a diffusive radio-opaque tip is attached to the terminal end through which the radiation is delivered and scattered throughout the inflatable balloon 18 . The light delivered through the inflatable balloon 18 is then absorbed by cells of the surrounding tissue, causing death or inactivation of the cells such that a reduction occurs in the mass of the tissue (e.g., the diameter of the stenosed lumen increases). In one embodiment, a photoactivatable chromophore, such as a psoralen (e.g., 8-methoxypsoralen), is delivered either locally or systemically to the treatment area 3 (See FIG. 3) prior to irradiation. The chromophore is then activated by exposure to light (e.g., visible light having a wavelength of about 420 nanometers when using 8-methoxypsoralen) and causes death of the cells in the treatment removal of the catheter device from the stenosed region, a reduction in cell mass is observed in the treatment area. Although the illustrated embodiments describe a system in which the balloon and irradiation means of the present invention are structurally distinct (with the balloon element 18 bonded directly to the catheter body 12 and the light-emitting fiber carried within an internal lumen 16 of the catheter body 12 ), it should be clear that a combined balloon and light fiber instrument can be substituted to achieve the same effect. Such an instrument (with a light emitter of an appropriate length and an appropriately sized balloon) can be constructed, for example, by following the teachings of U.S. Pat. No. 4,512,762 issued to Spears on Apr. 23, 1985 and incorporated herein by reference. Alternatively, the methods of the present invention can be practiced without a dilation balloon employing a simple radiationemitting catheter such as that disclosed in U.S. Pat. No. 5,254,112 issued to Sinofsky et al. on Oct. 19, 1993 or U.S. Pat. No. 5, 0553,033 issued to Clarke on Oct. 1, 1991, both of which are also incorporated herein by reference. Those skilled in the art will be able to recognize, or be able to ascertain using no more than routine experimentation, numerous other equivalents to the specific devices and procedures described herein. Such equivalents are considered to be within the scope of this invention and are covered by the following claims.
A method for treating in-stent restenosis using radiation having a wavelength sufficient to kill or promote cellular death (e.g., through programmed cell death), or otherwise remove smooth muscle cells which have proliferated, or which might otherwise proliferate, in the proximity of (i.e., within, around or adjacent to) a stent within a body lumen, causing (or potentially causing) at least partial blockage of the lumen. The treatment method includes irradiating smooth muscle cells in the region of the stenosis with non-ablative, cytotoxic radiation, such as UV radiation. A cytotoxic, photoactivatable chromophore may also be delivered to the treatment site prior to irradiation. The method can be used prophylactically or to treat in-stent restenosis after blockage has occurred without further damage to surrounding tissue.
0
FIELD OF THE INVENTION [0001] The present invention relates generally to communication systems, and more particularly to Short Message Service (SMS). BACKGROUND OF THE INVENTION [0002] Short Message Service (SMS) has become a very popular feature in communication systems. Because SMS messages are not time-dependent, an acknowledgement message typically is not sent to the sender of an SMS message. [0003] Currently, when a Mobile Switching Center (MSC) receives an SMS message intended for a mobile station that is not indicated to be located at the MSC, the MSC sends a failure notification to the SMS server. The MSC server does not attempt to deliver the SMS in such a scenario. Instead, the Home Location Register (HLR) waits for the mobile station to register with the HLR so that the SMS delivery may be reattempted. In the meantime, the sender is still waiting for the SMS delivery to complete. [0004] Therefore, a need exists for a method and system for reliably sending SMS messages to a mobile station when an MSC does not know where the mobile station is located. BRIEF SUMMARY OF THE INVENTION [0005] An exemplary embodiment of the present invention provides a method for delivering an SMS message. The MSC sends an alert message or page message to all subtending MMEs. [0006] An IWMSC sends an SMS message to the MSC. The SMS message is a request to send an SMS message to a mobile station. In accordance with an exemplary embodiment, the SGs association on the MSC between an MME and the MSC is not currently set. [0007] If the mobile station is not registered with the MSC, the MSC queries subtending MMEs, preferably by sending an alert message to all subtending MMEs. The alert messages help the MSC to determine whether the intended mobile station has registered with any of the MMEs. [0008] The MME to which the mobile station is registered an acknowledgement message to the MSC to indicate that the mobile station is registered with the associated MME. [0009] The MSC preferably stores the SMS message and forwards to the mobile station via the acking MME after receiving the alert acknowledgement message from the MME. [0010] In accordance with an exemplary embodiment, the mobile station sends a TAU (Tracking Area Update) message with combined TA/LA (Tracking Area/Location Area) updating to an eNodeB, which passes the TAU message to the responding MME. [0011] In response to the TAU message, the MME sends a Location Update message to the MSC. In response to the Location Update message, the MSC re-registers mobile the station so that the SGs association between the MME and the MSC can be re-established. [0012] The IWMSC sends an SMS message intended for the mobile station to the MSC. The MSC checks the SGs association for the mobile station. Since the MSC re-registered the mobile station and re-established an SGs association, the MSC acknowledges the receipt of the SMS message and processes the delivery of the SMS message to the mobile station. BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS [0013] FIG. 1 depicts a portion of a communication system in accordance with an exemplary embodiment of the present invention. [0014] FIG. 2 depicts a flow diagram of a method for delivering an SMS message in accordance with an exemplary embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION [0015] An exemplary embodiment of the present invention can be better understood with reference to FIGS. 1 and 2 . FIG. 1 depicts a portion 100 of a communication system in accordance with an exemplary embodiment of the present invention. Portion 100 includes mobile station 101 , eNodeB 103 , MME 105 , MME 115 , MME 125 , MSC 107 , and SMS-IWMSC (SMS Interworking MSC) 109 . [0016] Mobile station 101 is a device supporting voice and data communication using a wireless air interface. In an exemplary embodiment, mobile station 101 is a Circuit Switch Fall Back (CSFB) mobile station camping on LTE technology. [0017] eNodeB 103 is an LTE base station that communicates, over the air, with mobile station 101 . [0018] MME 105 , MME 115 , and MME 125 are Mobility Management Entities that each manage session states, authentication, paging, mobility with SGSN nodes, roaming, and other bearer management functions. [0019] MSC 107 is a Mobile Switching Center. In an exemplary embodiment, MSC 107 comprises a 3G MSC. MSC 107 is the network element that provides voice services and enables mobile terminals to communicate to the Public Switched Telephone Network (PSTN). [0020] SMS-IWMSC 109 is an MSC that is capable of receiving SMS messages from a mobile network and submitting the SMS messages to an appropriate Short Message Service Center (SMSC). [0021] FIG. 2 depicts a flow diagram 200 of a method for delivering an SMS message in accordance with an exemplary embodiment of the present invention. In this exemplary embodiment, the MSC sends an alert message to all subtending MMEs. In an alternate exemplary embodiment, the MSC can send a page message and deliver the SMS to the MME that responds to the page message. [0022] SMS-IWMSC 109 sends ForwardSMS message 217 to MSC 107 . ForwardSMS message 217 is a request to send an SMS message to mobile station 101 . In the exemplary embodiment depicted in FIG. 2 , mobile station 101 is not registered with MSC 107 . In an exemplary embodiment, the SGs association on MSC 107 between MME 115 and MSC 107 is not currently set. In a first exemplary embodiment, this can occur when a VLR record associated with mobile station 101 is deleted, for example due to VLR overload control or other administrative reasons. In a second exemplary embodiment, this can occur when the SGs association is equal to SGs-NULL. [0023] In accordance with the exemplary embodiment, MSC 107 queries subtending MMEs, in this exemplary embodiment MME 105 , MME 115 , and MME 125 , by sending SGsAP Alert Request message 213 to MME 115 , SGsAP Alert Request message 203 to MME 105 , and SGsAP Alert Request message 223 to MME 125 . The SGsAP Alert Request messages will help MSC 107 determine whether mobile station 101 has registered with any of the MMEs. In an alternate exemplary embodiment, MSC 107 sends a page message, preferably over an SGs interface, to corresponding MMEs and delivers ForwardSMS message 217 to the MME that responds to the page message. [0024] In this exemplary embodiment, mobile station 101 is registered with MME 115 . Therefore MME 105 sends SGs Alert Reject message 205 to MSC 107 and MME 125 sends SGs Alert Reject message 225 to MSC 107 . [0025] MME 115 sends SGsAP Alert Ack message 227 to MSC 107 . SGsAP Alert Ack message 227 indicates to MSC 107 that mobile station 101 is registered with MME 115 . [0026] In an exemplary embodiment, MSC 107 stores the SMS message and forwards to mobile station 101 via MME 115 after receiving SGsAP Alert Ack message 227 from MME 115 . [0027] In accordance with an exemplary embodiment, mobile station 101 sends a TAU (Tracking Area Update) message 311 , preferably with combined TA/LA (Tracking Area/Location Area) updating to eNodeB 103 . In an alternate exemplary embodiment, message 311 can be any message that indicates user activity by mobile station 101 . [0028] eNodeB 103 passes TAU message 311 to MME 115 via TAU message 313 . [0029] In response to TAU message 313 , MME 115 sends an SGsAP Location Update message 315 to MSC 107 . In response to SGsAP Location Update message 315 , MSC 107 re-registers mobile station 101 so that the SGs association between MME 115 and MSC 107 can be re-established. [0030] SMS-IWMSC 109 sends ForwardSMS message 317 to MSC 107 . ForwardSMS message 317 is intended for mobile station 101 . MSC 107 checks the SGs association for mobile station 101 . Since MSC 107 re-registered mobile station 101 and re-established an SGs association, MSC 107 acknowledges the receipt of ForwardSMS message 317 and processes the delivery of the SMS message to mobile station 101 . [0031] While this invention has been described in terms of certain examples thereof, it is not intended that it be limited to the above description, but rather only to the extent set forth in the claims that follow.
A Mobile Switching Center (MSC) receives a short message intended for a mobile station. The MSC determines whether the mobile station is registered at the MSC. If not registered, the MSC sends a query message to associated Mobility Management Entities (MMEs). One of the MMEs sends a message to the MSC indicating that the MME is serving the mobile station.
7
CROSS REFERENCE TO RELATED APPLICATION [0001] This application claims priority to U.S. Provisional Application No. 61/725,106 filed on Nov. 12, 2012. BACKGROUND [0002] A gas turbine engine typically includes a fan section, a compressor section, a combustor section and a turbine section. Air entering the compressor section is compressed and delivered into the combustion section where it is mixed with fuel and ignited to generate a high-speed exhaust gas flow. The high-speed exhaust gas flow expands through the turbine section to drive the compressor and the fan section. [0003] Typically, the gas turbine engine is supported under an aircraft wing on either side of the fuselage. However, such under-wing installations may not be compatible with unique aircraft configurations. Accordingly, different mounting locations for the engines such as at the rear of the fuselage are being considered. Different mountings locations present different challenges and require alternate engine configurations. [0004] A thrust reverser is utilized once an aircraft has landed, and creates a reverse thrust force to aid in slowing the aircraft. Typical thrust reversers and nozzles are components of the engine nacelle surrounding an under-wing mounted engine. Engines mounted within an aircraft fuselage do not include the same nacelle structures and therefore conventional thrust reversing devices may not be compatible. [0005] Alternate aircraft architectures may require alternate mounting locations of the gas turbine engines to enable specific wing and fuselage configurations. However, conventional gas turbine engine configurations have been developed to operate with conventional aircraft architectures. [0006] Accordingly, alternate gas turbine engine configurations may be required and developed to enable implementation of favorable aspects of alternate engine architectures. SUMMARY [0007] A propulsion system according to an exemplary embodiment of this disclosure, among other possible things includes first and second propulsors mounted at an aft portion of a fuselage, and first and second thrust reversers mounted proximate to corresponding first and second propulsors. Each of the first and second thrust reversers include respective thrust reverser doors, the thrust reverser doors rotatable to a deployed position such that longitudinal centerlines along the thrust reverser doors converge below the thrust reversers thereby reducing lift producible by redirected thrust. [0008] In a further embodiment of the foregoing propulsion system, the thrust reverser doors include an upper door and a lower door pivotally mounted for movement between a stowed position and the deployed position. [0009] In a further embodiment of any of the foregoing propulsion systems, the upper door and the lower door are pivotally mounted for movement along the longitudinal centerline that is angled relative to the vertical plane. [0010] In a further embodiment of any of the foregoing propulsion systems, includes a first engine core driving a first fan and a first bypass passage disposed along a first propulsor axis and a second engine core driving a second fan and a second bypass passage disposed along a second propulsor axis. [0011] In a further embodiment of any of the foregoing propulsion systems, the first and second thrust reversers includes corresponding first and second upper doors and first and second lower doors that are pivotally mounted for movement between a stowed position and the deployed position. [0012] In a further embodiment of any of the foregoing propulsion systems, the first and second upper doors and the first and second lower doors close on a centerline of corresponding ones of the first and second bypass passages to capture both a bypass flow stream and a core flow stream. [0013] An aircraft according to an exemplary embodiment of this disclosure, among other possible things includes a fuselage including an aft portion, a propulsion system supported within the aft portion of the fuselage, and a thrust reverser mounted in the aft portion of the fuselage proximate to the propulsion system for directing thrust in a direction to slow the aircraft. The thrust reverser directs thrust at an angle relative to a vertical plane. [0014] In a further embodiment of the foregoing aircraft, the propulsion system includes a first engine core driving a first fan within a first bypass passage disposed about a first propulsor axis and a second engine core driving a second fan within a second bypass passage disposed about a second propulsor axis and the thrust reverser inlcudes a first and second thrust reversers each directing thrust at an angle relative to the vertical plane. [0015] In a further embodiment of any of the foregoing aircrafts, the first and second thrust reversers are angled away from each other such that airflow directed above the first and second thrust reversers flows away from each other and thrust directed below the first and second thrust reversers combines to reduce excess lift. [0016] In a further embodiment of any of the foregoing aircrafts, the first and second thrust reversers include corresponding first and second upper doors and first and second lower doors that are pivotally mounted for movement between a stowed position and a deployed position. [0017] In a further embodiment of any of the foregoing aircrafts, the first and second doors and the first and second lower doors close on a corresponding one of the first propulsor axis and the second propulsor axis to capture both a bypass flow stream and a core flow stream. [0018] In a further embodiment of any of the foregoing aircrafts, the aircraft includes a vertical stabilizer extending upward from the aft portion of the fuselage and the first and second thrust reversers direct thrust away from the vertical stabilizer. [0019] In a further embodiment of any of the foregoing aircrafts, the vertical stabilizer is disposed between the first and second bypass passages. [0020] In a further embodiment of any of the foregoing aircrafts, the aircraft includes a horizontal stabilizer supported on the vertical stabilizer. [0021] Although the different examples have the specific components shown in the illustrations, embodiments of this disclosure are not limited to those particular combinations. It is possible to use some of the components or features from one of the examples in combination with features or components from another one of the examples. [0022] These and other features disclosed herein can be best understood from the following specification and drawings, the following of which is a brief description. BRIEF DESCRIPTION OF THE DRAWINGS [0023] FIG. 1 schematically shows an example aircraft with a propulsion system mounted within a fuselage. [0024] FIG. 2 is a schematic view of an example reverse flow gas turbine engine. [0025] FIG. 3 is a schematic view of view of an example thrust reverser in a stowed position. [0026] FIG. 4 is a schematic view of the example thrust reverser in a deployed position. [0027] FIG. 5 is a rear view of the thrust reverser in the deployed position. [0028] FIG. 6 is a rear view of the example thrust reverser in a stowed position. DETAILED DESCRIPTION [0029] Referring to the FIGS. 1 and 2 an aircraft 10 includes a fuselage 12 having wings 16 and a tail 14 . A propulsion system 18 is mounted in aft end 15 of the fuselage 12 . The propulsion system 18 includes first and second engine cores, which are reverse core gas turbine engines, 20 a - b that drive corresponding first and second propulsors, including fan sections 22 a - b. The first and second fan sections 22 a - b provide the propulsive thrust through corresponding first and second bypass passages 36 a - b. [0030] Each of the fan sections 22 a - b are disposed about corresponding first and second propulsor axis A 1 and A 2 . The first and second engine cores 20 a - b is disposed about a corresponding first and second engine axis B 1 and B 2 . That is the first engine core 20 a is disposed about the first engine axis B 1 and drives the first propulsor about the first propulsor axis A 1 . The second engine core 20 b is disposed about the second engine axis B 2 and drives the second fan section 20 b about the second propulsor axis A 2 . [0031] The example engine cores 20 a - b are gas generators that include a compressor 24 , a combustor 26 and a turbine 28 . Air is drawn in through inlets 32 a - b to the compressor 24 is compressed and communicated to a combustor 26 . In the combustor 26 , air is mixed with fuel and ignited to generate an exhaust gas stream that expands through the turbine 28 where energy is extracted and utilized to drive the compressor 24 and corresponding fan 22 a - b. In this example the engine cores 20 a - b drive the corresponding fan 22 a - b through a geared architecture 30 a - b that is part of the propulsor. [0032] In the disclosed example, each of the first and second propulsors 22 a - b is mounted substantially parallel to each other about respective propulsor axes A 1 , A 2 . The first and second engine axes B 1 , B 2 are disposed at an angle 34 relative to the corresponding propulsor axis A 1 , A 2 . The engine cores 20 a - b are also angled away from each other at an angle 38 . [0033] Referring to FIGS. 3 and 4 , the aircraft includes a thrust reverser for directing thrust to slow the aircraft 10 upon landing. The disclosed thrust reverser includes a first thrust reverser 40 a and a second thrust reverser 40 b for corresponding bypass passages 36 a - b. The first and second thrust reversers 40 a - b include corresponding first and second upper doors 42 a, 42 b and first and second lower doors 44 a, 44 b. [0034] The upper and lower doors 42 a - b, 44 a - b are movable between a stowed position ( FIG. 3 ) and a deployed position ( FIG. 4 ). Movement of the upper and lower doors 42 a - b, 44 a - b, is facilitated by pivots 48 that support rotation between stowed and deployed positions. An actuator 46 is provided to move the upper and lower doors 42 a - b, 44 a - b between the stowed and deployed positions. [0035] In the stowed position, thrust flows unimpeded through the bypass passages 36 a - b. In the deployed position, thrust is directed upwardly as indicated at 52 and downwardly as indicated at 56 about the propulsor axes A 1 , A 2 . The upward and downward directed thrust 52 , 54 slows the aircraft 10 during landing. In some aircraft 10 architectures, the downward directed thrust 54 can generate undesired lift by directing thrust under the aircraft fuselage 12 or other surface. As appreciated, thrust that generates lift, or interferes with desired aircraft aerodynamic performance is undesirable. [0036] Referring to FIGS. 5 and 6 , the example thrust reversers 40 a - b are angled relative to a vertical plane 50 to reduce and/or eliminate the generation of lift on the aircraft 10 . The first and second thrust reversers 40 a - b are circumferentially oriented, or clocked about the corresponding propulsor axes A 1 , A 2 to direct upward thrust 52 away from the vertical plane 50 . [0037] In this example the first and second thrust reversers 40 a - b close about respective centerlines 58 a, 58 b that are angled away from each other above the axes A 1 , A 2 . The angle 54 between the centerlines 58 a, 58 b enables direction of upward thrust 52 away from the vertical plane 50 and vertical stabilizer 19 . [0038] The angle 54 results in the centerlines 58 a - b intersecting at a point below the axes A 1 , A 2 . Accordingly, downward thrust 56 combine below the axes A 1 , A 2 and the aircraft fuselage 12 to effectively cancel any resulting lift forces generated on the fuselage 12 . [0039] Accordingly, the disclosed thrust reversers 40 a - b are angled to avoid thrust impingement on the tail 14 and also combine downward thrust to substantially reduce any generation of lift on the aircraft. [0040] Although an example embodiment has been disclosed, a worker of ordinary skill in this art would recognize that certain modifications would come within the scope of this disclosure. For that reason, the following claims should be studied to determine the scope and content of this disclosure.
An aircraft includes a fuselage including a propulsion system supported within an aft portion. A thrust reverser is mounted proximate to the propulsion system for directing thrust in a direction to slow the aircraft. The thrust reverser directs thrust at an angle relative to a vertical plane to reduce interference on control surfaces and reduce generation of underbody lift.
5
This is a continuation-in-part of patent application Ser. No. 06/761,759, now abandoned. BACKGROUND OF THE INVENTION 1. Technical Field This invention relates to shutoff nozzle valves for sandblasting equipment of the type used to control the air and sand pressure flow at the users point of use. 2. Description of the Prior Art Prior Art devices of this type have relied on a variety of configurations, such as a ball valve using teflon or urethane seals, all of which leak and become unstable after a short exposure to the air and sand mix. Other valves rely on a variety of different structures, see for example U.S. Pat. Nos. 2,641,087, 4,269,359, 2,989,283, 2,247,773 and a nozzle shutoff valve manufactured by P. K. Lindsay, Inc., Model 66E-V-D. In U.S. Pat. No. 2,641,087, a valve is disclosed which uses a hose pinching mechanism which restricts the air and sand flow stream by progressively reducing the opening in a resilient tube by pinching the tube with a movable arm. U.S. Pat. No. 4,269,359 shows a nozzle shutoff valve having a resilient pad movably positioned on to the end opening in a sandblast nozzle. A spring urged arm moves the pad into an exterior sealing relation by the activation of a lever control held by the operator on the nozzle grip. In U.S. Pat. No. 2,989,283 a self sealing fluid valve configuration is shown wherein a resilient conduit is formed in which a resilient ball valve is positioned. U.S. Pat. No. 2,247,773 discloses a fluid swing check valve having a closure member on a hinge to seal an opening by engagement with a annular valve seat. This valve is designed for use in non-abrasive fluid flow environments. In Lindsay Company, valve M-66E-V-D a movable arm having a sealing element is positioned in the air sand flow sealing the same. The sealing element is a combination of a steel washer, rubber washer and valve stem. Applicant's device is a self closing valve that provides a positive shutoff of the air and sand stream regardless of the valve position upon actuation. SUMMARY OF THE INVENTION A shutoff valve for use exclusively with sandblasting equipment that provides a fail safe positive shutoff of the sand and air stream at the nozzle site. The valve utilizes a pressure urged valve element that resist wear and associated leakage by reducing exposure to stream intraned abrasive material by a unique sealing configuration that imparts a wear reducing stream flow configuration around the valve element and seat. DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross sectional view of the shutoff valve nozzle; FIG. 2 is a section on lines 2--2 of FIG. 1 of the shutoff valve; and FIG. 3 is a cross sectional view of a portion of the shutoff valve showing flow stream configuration within. DESCRIPTION OF THE PREFERRED EMBODIMENT A sandblast nozzle shutoff valve 10 can be seen in FIGS. 1 and 2 of the drawings having a housing 11 with oppositely disposed openings 12 and 13 and a access plate and gasket 14 and 14A positioned therebetween. A nozzle fitting 15 is threadably secured within the opening 12. The nozzle fitting 15 is apertured at 15A with an area of reduced internal diameter defined by an internal annular flange 16. The nozzle fitting 15 is externally threaded between the opening 12 and a annular flange 17. A annular nozzle gasket 18 is positioned on the internal annular flange 16 in sealing relationship to a nozzle 19 shown in broken lines in FIG. 1 of the drawings. A valve seat gasket 20 is positioned on the other side of said internal annular ring 16. The nozzle fitting is tapered at 21 outwardly along the apertured 15A within the opening 12 in the housing 11. A wear tube 22 is positioned within the housing between the openings 12 and 13 with the upper portion of the tube 22 at 23 cut away. Referring now to FIG. 2 of the drawings, a control armature 24 can be seen extending transversely through the housing 11 above the wear tube 22. A pair of control armature bushings 25A and 25B are threadably secured in oppositely disposed apertures in the housing. O-rings 27 are positioned around the control armature 24 against the bushings 25 sealing the control armature 24 thereto preventing leaks therearound. A center portion 28 of the control armature 24 is of a larger diameter with a flattened portion 29 within the center portion. A valve flapper 30 having a generally flat rectangular configuration is secured to and extends from the flattened portion 29 by a fastener F. The free end of the valve flapper 30 has its end rounded and is apertured centrally inwardly from its end. A power cup 32 is of an annular configuration having a right angularly disposed tapered flange 33 extending around its perimeter. The power cup is apertured at its center point and is secured to one side of the valve flapper 30 by a fastener F aligned within registering apertures as here and before described. A ball stop holder 34 is secured to the other side of said valve flapper opposite the power cup 32. The ball stop holder 34 has an annular recess portion 35 within into which is secured a half arcuate valve seal element 36. The annular recess portion 35 defines an annular lip 35A on the ball stop holder 34 that extends around a portion of the half arcuate valve seal element 36. Referring now to FIG. 2 of the drawings, the power cup 32 is secured to the valve flapper 30 so as to be aligned within the wear tube 22 with equal clearance between the perimeter edge of the power cup and the wear tube 22. An equal flow pattern of air and sand between the wear tube and power cup is important during the closure of the valve. It is this flow characteristic around the power cup in combination with the shape of the ball stop holder 34 and its extending annular lip 35A that induces a unique flow pattern around the seal element 36 as best seen in FIG. 3 of the drawings. The flow pattern set up by the annular flange is characteristic of the principles of flow dynamics in that flow will tend to follow the surface contour of a flow disrupting article given the relative velocity of the flow. In this instance it is critical to have the initial contour flow pattern established by the annular flange 33 so that as the flow pattern follows the down stream contours it will engage the annular lip 35A and pass for the most part around the sealing element 36. The greatest potential for abrasive wear to the sealing member occurs as the valve is closed due to the increase velocity through the reduced opening. According to general principles of fluid mechanics, the flow leaving a surface tends to continue along the flow path established at the exit location on the surface. Accordingly, since the flow is divided by the downstream-most location on the annular lip away from the seal, the abrasive mixture will tend to miss that seal thereby reducing abrasion on the arcuate valve seal 36 which is effectively, in this instance, positioned in a "shielded" location with respect to the valve seal. Referring now to FIGS. 1 and 2 of the drawings, an offset handle 37 can be seen extending from one end of the control armature 24. A spring configuration 38 is connected to the other end of the control arm 24 outside of the housing 11. By moving the offset handle 37 the control armature 24 is rotated, swinging the attached valve flapper towards and away from the opening 12 in the housing 11. The spring configuration 38 urges the handle and the attached control armature constantly towards a closed position requiring the user to pull the handle upwardly towards parallel alignment with the housing in order to open the shutoff valve as seen in broken lines in FIG. 1 of the drawings. In operation, the valve flapper is moved into the stream of air and sand supplied to the shutoff valve via the inlet line L shown in broken lines extending from the opening 13 in the housing 11. As the valve flapper is advanced the pressurized air and sand stream catches the power cup 32 which has a greater surface area than the valve seal 36 and forces the same towards the opening 12 in the housing. The valve seal 36 registers in sealing relation to the valve seat gasket 20 effectively shutting of the flow of air and sand before the nozzle 19. To open the shutoff valve the operator moves the handle 37 from closed position B in an arcuate fashion to an open position shown in broken lines at position A. It will be evident from the above description that as the power cup impinges the sand and air stream flow that the differential size configuration of the power cup forces the valve flapper and moves the same with its attached half arcuate valve seal 36 into sealing relation in the aperture while reducing potential abrasion wear on the valve seal 36.
A shutoff valve for use on sandblasting equipment wherein the valve provides a fail safe positive closure of air and sand pressure stream at the nozzle where the operator is. The sand and air pressure stream provides a positive force on the valve assisting the closure and maintaining a tight seal against air and sand infiltration to the nozzle.
5
FIELD OF THE INVENTION [0001] Providing a different technology to cook in a depth way maize, other grains, cereals or legumes, increasing its internal temperature and humidity, in order to obtain a controlled and homogeneous transformation of its components, reducing the loss of pericarp, the loss of process, gas emissions and contaminated wastewater. BACKGROUND OF THE INVENT/ON [0002] The state of the art used in the tortilla shops for the production of nixtamal involves pouring maize, without prior washing, into an open container and in which excess lime and water is added, in the bottom of the tank is placed a burner, generally butane-based, that is ignited until the water reaches a temperature that can range between 88° C. and 96° C. depending on the height above sea level, the necessary time may range between 60 and 90 minutes, depending on the amount of maize, the capacity and efficiency of the burner. Subsequently it is allowed to stand in the cooking water for a period of 10 to 12 hours, after the time elapsed, it proceeds to washing, and grinding it. [0003] The Nixtamal that is produced in this way loses most maize pericarp, component composed mainly of insoluble vegetable fiber, vitamins, minerals and antioxidants naturally found therein, as its dilution by excess lime, they are throwed away with the wastewater to the drainage. The tortilla/maize performance or rate that is obtained with this nixtamal quality ranges between 130 and 150 kilograms of tortilla per 100 kilograms of maize. [0004] From traditional tortilla shops, family-scale business, 90% about, working within a production capacity range of 300 to 800 kg of tortillas per day, for this is necessary to produce 350 to 900 kilograms of nixtamal daily. In these businesses, and in similar that work using nixtamal flour as raw material, is supported almost the entire supply of tortillas in Mexico. [0005] From nixtamal characteristics depend significantly the results both economic and product quality of the tortilla shops, however, so far it has not been given sufficient importance and it lacks of equipment with new technologies that improve the procedure for cooking maize, as customary to level of the traditional tortilla shop, equipments to help them improve its profitability and product and being compact, simple to install, easily operated and early return on investment. [0006] The way as currently is produced Nixtamal is susceptible of widely improved, observing these opportunities for improvement, is that a new especial apparatus was designed, thereby may be work under process conditions, controlled and different to produce a better nixtamal, a High Performance Integral Nixtamal. [0007] The total of the tortilla shops operating in the country approximately 60% of them use maize as raw material to produce nixtamal, that when milled, it produces necessary dough to make tortilla, the rest uses nixtamalized maize flour, product that is made in large industrial facilities and which, when moisturizing it, produces dough which becomes tortilla. [0008] The Tortilla/Maize transformation ratio with the traditional system depends on the control degree on the operation thereof and is within a range of 130 to 150 kg tortilla per 100 kg maize. The ones that use nixtamalized maize flour operate within a range of 175 to 185 kilograms tortilla per 100 kilograms flour. [0009] When working with a tortilla shop with High Performance Integral Nixtamal such as that produced with the process and special equipment that is sought to be protected with the patent application described here, is obtained a transformation ratio, using maize as raw material of 170 to 180 kilograms Tortilla per 100 kilograms maize. [0010] This new technology applied to maize and other grains satisfactorily resolves current, ancestral problems, in tortilla shops installed in the country and that use maize as raw material, providing improvements such as: significantly reducing the time required for cooking maize and obtaining Nixtamal; to prevent further losing an important part of vegetable fiber, vitamins, minerals and antioxidants that are part of the grain, constituting a loss that affects the production cost and discredit nutritional properties of the tortilla; significantly reducing the flow of contaminated wastewater; increasing the tortilla/maize ratio, performance, profiting production productivity and cost, when being able to obtain the same amount of tortilla with less maize; decreasing the production cost by reducing consumption of fuel required for cooking; to help improve the ecological environment by reducing CO 2 emissions to the atmosphere and the wastewater flow to the drains. [0017] The process further provides other important advantages like: obtaining a saving within a range of 40% to 50% in the fuel consumption necessary for cooking the maize, this advantage integrated to obtain a higher performance in the conversion of maize to tortilla, will benefit the economy of business thousands making them more profitable. [0018] A significant positive consequence by the reduction in fuel consumption is the decreasing in the same proportion, in the flue gas emissions, mainly CO 2 , gases which cause greenhouse effect causing a change in weather patterns being observed. [0019] Another important advantage is that tortilla that is obtained with High Performance Integral Nixtamal, processed with this system, has better nutritional properties as it preserves practically, all components contained in the pericarp, like: as dietary or insoluble vegetal fiber, vitamins, minerals and antioxidants, same as in the traditional process are lost in large part since are diluted with cooking water and discarded, literally to the drain, further with this system the tortilla that is obtained is digested and assimilates better by its fiber additional content and higher gelatinization of the maize starches, advantages obtained with the depth cooking process at a higher pressure and temperature than the traditional process. [0020] It is an advantage to increase up to two and a half times the content of dietary or vegetal fiber since the gastrointestinal system should not digest nor assimilate and instead of it does help to cause a sense of satiety decreasing appetite and is achieved a satisfaction with lower intake of food. [0021] These advantages will benefit millions of consumers because the tortilla is the basis of the daily diet in Mexico. [0022] They are reported in national censuses, annual consumptions per capita on the order of 120 kg, this is an average of 328 grams per day which is equivalent to about 12 tortillas. [0023] The results discussed here were obtained in a real way and scale of an regular tortilla shot, since in addition to having designed and manufactured this special system of cooking maize for the production of High Performance Integral Nixtamal and reason for this request, it also was installed a commercial stone mill for milling nixtamal and producing dough and a commercial tortilla machine in order to produce tortillas. In this manner it has a pilot facility capable of producing the new High Performance Integrated Nixtamal and dough, to make 3000 tortillas per hour, of a quality higher than the standard, this facility has been operated daily for several weeks with the results here presented, during this period it has been sold the tortilla produced with the purpose of verifying the acceptance from public. BRIEF DESCRIPTION OF THE DRAWINGS [0024] FIG. 1 is a flowchart of the process. [0025] FIG. 2 shows a general arrangement of equipment. [0026] FIG. 3 shows a detailed reactor design. DETAILED DESCRIPTION OF THE INVENTION [0027] The characteristic details of this novel system to process maize and other grains, cereals or legumes will be given clearly in the following description. The equipments comprising the production system, necessary to provide the necessary conditions of the process, are a basket where maize is deposited to be thermally treated, an electric winch to move or lift the process basket and insert it in the wash tank, in which, with water and agitation are removed insecticide residues, dust and foreign material; also has a fixed structure but swivel where is installed electric winch necessary to move the wash tank basket to reactor cooking tank, where they will be generate the thermal and pressure conditions required by the process and where is achieved the transformation of maize in a High Performance integrated Nixtamal. [0028] FIG. 1 shows a flowchart of the required process for depth cooking of maize and obtaining of a High Performance Integrated Nixtamal and specially designed equipment for this purpose. The process begins by introducing the basket ( 1 ) with maize ( 2 ), this tank is supplied with water at room temperature, subsequently is stirred maize to remove dust adhered to it, insecticide residues used in grain storage and floating separate foreign matter other than maize. Simultaneously is being recirculating water of the maize wash by pump ( 7 ) that sends dirty water to the filter ( 8 ) which removes impurities and returns the clean water to the wash tank. The previous washing procedure maize despite being very important it is something that is rarely made. [0029] Once the maize is clean with the assistance of the support structure and the electrical winch, the process basket is removed of the washing tank ( 2 ) and with assistance of the rotating structure and the winch the process basket ( 1 ) is inserting to the reactor cooking tank ( 3 ), hot water is added at 60 degrees Celsius from the solar heater ( 4 ) and hydrated lime at a ratio which may range with maize type, between 1 and 3 parts by maize thousand, stirring to homogenize. The combustion chamber ( 5 ) is ignited which discharges combustion gases to the reactor ( 3 ) and the same to the atmosphere through chimney ( 6 ). Once the combustion chamber ( 5 ) is ignited, the temperature inside reactor ( 3 ) is increased; depending on the maize variety and age, the temperature rises to reach 90 to 100 degrees Celsius, once a temperature is reached at a time which may range from 12 to 15 minutes, the combustion in the chamber ( 5 ) is suspended, from this point it initiates a rest time which may range between 20 and 30 minutes, in order to homogenize the internal humidity taken by the grain, time at which is maintained temperature in the reactor cooking tank ( 3 ). When the rest time is finished, the combustion chamber ( 5 ) is re-ignited and temperature is raised inside reactor to a level which may range between 115 and 120 degrees Celsius and a pressure within a range of 1 to 1.3 kg/cm 2 , thus it achieves a depth or higher penetration cooking in the grain without losing the pericarp; by reaching these process conditions, the combustion in the chamber ( 5 ) is suspended and starts an rest period at constant temperature and by a time which may range between 5 and 10 minutes, on finishing this step, it proceeds to reduce pressure inside reactor up to atmospheric pressure level, it proceeds to open lid thereof, and with assistance of the winch and the support rotary structure the process basket ( 1 ) is removed and positions inside the washing tank ( 2 ) for cooling with water from the purifying equipment, water when passing through the ultraviolet ray lamps and with ozone injection it is purified, lowering bacterial content. In this way a product is obtained with a longer duration, without having to add preservative additives. Once nixtamal temperature is within a range 25 to 35 degrees Celsius, it unloads the process basket ( 1 ) and nixtamal is transferred to mill. At this point the process ends for the production of High Performance Integral Nixtamal. [0030] FIG. 2 shows the equipment involved in the process and not shown in the above flowchart: the basket ( 1 ) wherein maize is loaded; the wash tank ( 2 ) wherein the basket ( 1 ) is initially introduced; the electric winch ( 9 ) and rotating support structure ( 10 ) are necessary to transfer the basket to the reactor ( 3 ); the reactor lid ( 12 ) which opens to admit basket ( 1 ) within reactor ( 3 ); a hinge and clamping system of the lid ( 14 ); the solar heater ( 4 ) supplying hot water to the rector; gas burners ( 15 ) providing required thermal energy; the combustion chamber ( 5 ) providing required temperature to the burners ( 15 ) to ensure complete combustion of the gas; a chimney ( 6 ) that induces secondary air flow and combustion gases through chamber and reactor ( 3 ) and discharge them into the atmosphere; security device ( 13 ) against vapor overpressure and temperature measurement and pressure inside reactor ( 3 ); bactericidal treatment equipment ( 11 ) to purify water used at the end of the process to cool Nixtamal contained in the basket ( 1 ) and returning to the washing tank ( 2 ) for its cooling. [0042] FIG. 3 , reactor drawing specially designed to generate required specific conditions of the production process of the High Performance integrated Nixtamal. [0043] Drawing shows the most important parts that integrate the reactor and are following: reaction tank ( 1 ), cylindrical metal container designed to operate at pressure and high temperature; upper metal lid ( 2 ) which can be rotated and placed vertically with hinge support ( 3 ) for accepting the basket inside the reaction tank containing the maize to be processed. flanges ( 4 ) installed in the tank ( 1 ) and the lid ( 2 ) for clamping both sides and sealing the inner and preventing heat and steam leakages during work; internal support ( 5 ), welded to the tank ( 1 ) to support basket; metal chimney ( 6 ), part of system that will cause by natural induction an air flow through reactor and combustion chamber ( 7 ); combustion chamber ( 7 ), metal container that provides a high temperature inside atmosphere in order of 800 degrees Centigrade to ensure that the fuel is fed to the burners ( 8 ) to burn efficiently without loss into the atmosphere; chamber ( 7 ) is thermally insulated with the purpose of preventing heat losses and has a device ( 9 ) for controlling the secondary air flow entering to the system; hot air supplied by the chamber ( 7 ) is induced by chimney ( 6 ) within the high temperature chamber ( 10 ) located at the reactor bottom, chamber formed by a concentric metal ring ( 11 ) welded to the outer wall of the pressure tank ( 1 ) and to the inner wall and outer cylindrical concentric metal bottom ( 12 ), this chamber ( 10 ) directs the ascending heated gas flow to the second chamber ( 13 ) through an annular space ( 12 ) comprising between wall of two tanks, space located and designed with an area for conducting gas flow and obtaining maximize heat transfer to the interior of pressure tank ( 1 ); the reactor comprises three serial additional chambers ( 13 ), ( 14 ) and ( 15 ) for heat transfer to the interior of tank ( 1 ) formed by directional concentric metal rings ( 16 ) ( 17 ) and ( 18 ) respectively, welded to the outer wall of the tank ( 1 ) and to the interior of the tank ( 12 ). Each chamber mentioned has an annular space ( 19 ), ( 20 ), and ( 21 ) respectively, spaces located between two tanks, so as to direct the ascending gas flow between a chamber and the next one, and until gas outlet to the chimney ( 6 ); the outer tank is thermally insulated by 3 inch ceramic fiber ( 22 ) which at the same time is protected by a stainless steel metal cover; for facilitating control of process conditions, it has a bimetallic thermometer ( 23 ) and a pressure gauge ( 24 ), both located in the lid ( 2 ). it has a safety device against overpressure ( 25 ) located on the top lid ( 2 ).
A process and reactor used for the depth thermal treatment in maize for producing High Performance Integral Nixtamal, a process for treating maize under conditions different from known ones and by which a new product can be manufactured which has been called High Performance Integral Nixtamal.
0
BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a sheet transfer system, and more particularly to a sheet transfer system for transferring sheets, on which an image is recorded by an image forming system such as a printer or a copier, to a tray. 2. Description of the Related Art FIG. 9 shows a typical printer. A paper supply table 2 is disposed on one side of a printer body 1 and printing papers 3 are stacked on the paper supply table 2. The printing papers 3 are taken in the printer body 1 by an intake roller 4 and only the uppermost printing paper in the stack is separated from the stack and fed into the printer body 1 by a pair of separator rollers 5. The printing paper 3 thus supplied to the printer body 1 is passed through a resist roller 6 and an ink transfer drum 7, whereby an image is recorded on the printing paper 3 by stencil printing. The printing paper 3 bearing thereon a printed image is transferred by a sheet transfer system 8 and discharged to a tray 9 on the other side of the printer body 1. In the case of a printer, since the printed paper is still wet with ink, the printed paper is generally transferred by use of a vacuum conveyor (a suction belt) not to contact the front side of the printed paper bearing thereon the printed image. As is well known in the art, the vacuum conveyor generally comprises a pair of conveyor belts 8a which extend in parallel to the direction of transfer on opposite sides of the path along which the printed papers are transferred, and a vacuum fan 8b disposed between the conveyor belts 8a below them. When the vacuum fan 8b is operated to generate suction force, the printed paper is attracted against the conveyor belts 8a under the suction force and when the conveyor belts 8a are driven, the printed paper is conveyed and discharged onto the tray 9. Conventionally the vacuum fan 8b is disposed at the middle of the conveyor belts 8a as seen in the longitudinal direction thereof. This is for generating the suction force as uniform as possible over the entire area of the transfer area. However, in fact, the suction force is most strong at the middle of the conveyor belts 8a where the vacuum fan 8b is disposed and is gradually reduced toward the ends of the conveyor belts 8a. Further when the area of the part of the printed paper on which the suction force from the vacuum fan 8b acts is reduced, the attracting force (i.e., the paper holding force) is naturally weakened. When the attracting force is weak, the rotating force of the conveyor belts 8a cannot be efficiently transmitted to the printed paper and the transfer force is weakened. As a result, when the trailing end of the printed paper passes the middle portion of the transfer path, where the vacuum fan 8b is disposed, the printed paper comes to exist only where the attractive force is weak and the transfer force is abruptly weakened. Further when the leading end portion of the printed paper is transferred beyond the downstream end of the conveyor belts 8a, the area of the part of the printed paper on which the suction force from the vacuum fan 8b acts is reduced, which also results in a weak transfer force. When the transfer force is weakened, the printed paper stalls and sometimes cannot be properly discharged. Further there arises a problem that the printed paper cannot be ejected by a desired distance and cannot be positioned in place on the tray so that the printed papers are stacked with their edges aligned with each other. SUMMARY OF THE INVENTION In view of the foregoing observations and description, the primary object of the present invention is to provide a sheet transfer system which can constantly provide a desired transfer force to the printed paper and surely discharge the printed paper. In accordance with the present invention, there is provided a sheet transfer system for transferring sheets on which an image is recorded by an image forming system and discharging the sheets to a tray, the sheet transfer system comprising a conveyor belt and an attracting force generating means which generates an attracting force for attracting the sheets against the conveyor belt, wherein the improvement comprises that the attracting force is stronger at the downstream side portion of the conveyor belt. The expression "the attracting force is stronger at the downstream side portion of the conveyor belt" means that the attracting force is relatively strong at the downstream side portion as compared with that at the upstream side portion or the central portion. For example, the attracting force can be made stronger at the downstream side portion of the conveyor belt by disposing the attracting force generating means on the downstream side of the middle of the conveyor belt as seen in the direction of transfer. In one embodiment of the present invention, a plurality of first vacuum holes are formed in the conveyor belt. A guide plate is provided below the part of the conveyor belt which contributes to transfer of the sheet and a plurality of second vacuum holes are formed in the guide plate at a part where the second vacuum holes can be aligned with the first vacuum holes as the conveyor belt runs so that the attracting force generated by the attracting force generating means acts on the sheet through the first and second vacuum holes and the effective area which actually contributes to supplying the attracting force to the sheet to be transferred is determined by the area over which the first and second vacuum holes overlap with each other. The attracting force can be made stronger at the downstream side portion of the conveyor belt by increasing the area over which the first and second vacuum holes overlap with each other at the downstream side portion of the conveyor belt. An air blow means may be provided above the downstream side of the conveyor belt to urge the sheet toward the conveyor belt by the pressure of air blown from the air blow means. A plurality of cutaway portions may be formed on a downstream side pulley around which the conveyor belt is passed so that the attracting force can be applied through the cutaway portions. In the transfer system of the present invention, even when the leading end portion of the sheet is transferred beyond the downstream end of the conveyor belt and the area of the part of the printed paper on which the suction force from the vacuum fan acts is reduced, the sheet can be still firmly held on the conveyor belt under a desired attracting force, whereby a desired transfer force can be applied to the sheet until it is finally discharged onto the tray. Thus the aforesaid problems that the sheet stalls and sometimes cannot be properly discharged, or the sheet cannot be ejected by a desired distance and cannot be positioned in place on the tray so that the sheets are stacked with their edges aligned with each other can be overcome. Further since the attracting force is weaker at the upstream side end portion than the downstream side end portion, the following problem can be overcome. That is, when a sheet is delivered from an upstream side sheet transfer system to a downstream side sheet transfer system, the sheet once comes to extend over both the transfer systems. In such a case, when the transfer speed of the downstream side sheet transfer system is lower than that of the upstream side transfer system, the central portion of the sheet can be bulged upward due to the difference in the transfer speed since both the leading end portion and the trailing end portion of the sheet are held by the respective transfer systems. However when the attracting force is weaker at the upstream side end portion than at the downstream side end portion, the sheet holding force of the upstream side transfer system prevails over that of the downstream side transfer system and the sheet can be smoothly delivered to the downstream side transfer system without the sheet being deformed. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a front view of a printer in which a sheet transfer system in accordance with a first embodiment of the present invention is employed, FIG. 2 is a front view of the sheet transfer system, FIG. 3 is a plan view of the sheet transfer system, FIG. 4 is a front view of a sheet transfer system in accordance with a second embodiment of the present invention, FIG. 5 is a side view of the sheet transfer system, FIG. 6 is a plan view of the sheet transfer system, FIG. 7A is a plan view of a sheet transfer system in accordance with a third embodiment of the present invention, FIG. 7B is a rear view of the sheet transfer system, FIG. 8 is a front view showing a printer attached with a sorter in which a sheet transfer system in accordance with the present invention is employed, and FIG. 9 is a front view of a printer provided with a conventional sheet transfer system. DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1, a sheet transfer system 10 in accordance with a first embodiment of the present invention is disposed inside a printer body 1 of a stencil printer. The printer shown in FIG. 1 is substantially the same as that shown in FIG. 9 except the sheet transfer system, and accordingly the elements analogous to those shown in FIG. 9 are given the reference numerals. The sheet transfer system 10 is a vacuum conveyor and basically comprises a pair of conveyor belts 11 which extend in parallel to the direction of transfer of the printed paper on opposite sides of the path along which the printed papers are transferred, and a vacuum fan 12 disposed between the conveyor belts 11 below them. In the sheet transfer system 10, the printed paper is attracted against the conveyor belts 11 under suction generated by the vacuum fan 12. In this embodiment, the vacuum fan 12 is disposed on the downstream side of the middle of the conveyor belts 11 as seen in the direction of transfer. More specifically, as clearly shown in FIGS. 2 and 3, the vacuum fan 12 is disposed in the downstream side end portion of the sheet transfer system 10. With this arrangement, the suction force is the strongest in the downstream side end portion of the sheet transfer passage above the vacuum fan 12 and the weakest in the upstream side end portion. That is, the suction force is gradually increased from the upstream end toward the downstream end. A flat guide plate 13 extends horizontally below the upper run of the conveyor belts 11 substantially over entire area of the sheet transfer system 10. A casing 14 which opens upward is mounted on the lower surface of the guide plate 13 in a predetermined position. The vacuum fan 12 is mounted on the bottom of the casing 14 at the downstream side end portion of the casing 14. The inner space of the casing 14 is communicated with the vacuum fan 12 through an opening formed in the bottom of the casing 14. When the vacuum fan 12 is operated, air in the casing 14 is evacuated and suction force is generated. A drive shaft 15 extends horizontally in perpendicular to the direction of transfer on the upstream side of the sheet transfer system 10 and a pair of drive pulleys 16 are mounted on the drive shaft 15 at a predetermined distance from each other. The drive shaft 15 is rotated at a predetermined speed by a drive motor (not shown). A driven shaft 17 extends horizontally in parallel to the drive shaft 15 inside the casing 14 on the downstream side of the casing 14. Opposite end portions of the driven shaft 17 are supported for rotation on the side walls of the casing 14. A pair of driven pulleys 18 are mounted on the driven shaft 17 at a distance from each other. Thus the driven pulleys 18 are disposed inside the casing 14. The distance between the driven pulleys 18 is equal to that between the drive pulleys 16. A cutaway portion 13a is formed in the guide plate 13 at a part opposed to each driven pulley 18 and the driven pulley 18 projects outside through the cutaway portion 13a. Each conveyor belt 11 is passed around one of the drive pulleys 16 and one of the driven pulleys 18 which are opposed to each other in the direction of transfer. The shape of the cutaway portion 13a is similar to that shown in FIG. 5. When the drive shaft 15 is rotated, the conveyor belts 11 are run and the driven pulleys 17 are rotated by way of the drive pulleys 16. The parts of the conveyor belts 11 which are positioned above the guide plate 13 are able to contact the printed paper and contribute to transfer of the printed paper. The upper surface of the guide plate 13 is in contact with the conveyor belts 11 and the part of the upper surface of the guide plate 13 between the conveyor belts 11 supports the printed paper together with the conveyor belts 11. Each conveyor belt 11 is provided with a plurality of first vacuum holes 11a which are circular holes of the same diameter and are arranged in two rows at regular intervals. The first vacuum holes 11a in one row is shifted from those in the other row in the longitudinal direction of the conveyor belt 11 so that each first vacuum hole 11a in one row is positioned at the middle of adjacent two first vacuum holes 11a in the other row as seen in the transverse direction of the conveyor belt 11. A plurality of second vacuum holes 13b are formed in the guide plate 13 at the portion opposed to each conveyor belt 11. The second vacuum holes 13b are arranged in two rows in the same manner as the first vacuum holes 11a. Each of the second vacuum holes 13b is in the form of a slit extending along the axis of the row of the first vacuum holes 11a. The effective area which actually contributes to supplying suction force to the printed paper to be transferred is the overlapping portion of the first and second vacuum holes 11a and 13b. When air in the casing 14 is evacuated by the vacuum fan 12, air above the guide plate 13 is sucked into the casing 14 through the overlapping portion of the first and second vacuum holes 11a and 13b and the printed paper on the conveyor belts 11 are pressed against the conveyor belts 11a. Then when the conveyor belts 11 are run, the printed paper on the belts 11 are conveyed. The widths of the second vacuum holes 13b differ in the longitudinal direction of the conveyor belts 11. That is, the widths w of the second vacuum holes 13b on the upstream side are smaller than the widths w' of the second vacuum holes 13b on the downstream side. As a result, the suction force acting on the printed paper is larger on the downstream side than on the upstream side. Thus in this embodiment, the attracting force acting on the printed paper is increased from the upstream side toward the downstream side by shifting the vacuum fan 12 toward the downstream side and making the widths of the second vacuum holes 13a larger on the downstream side than on the upstream side, whereby the printed paper can be surely held until it is discharged to the tray and can be discharged in an optical manner. Further in this particular embodiment, a plurality of cutaway portions 18a are formed in each of the driven pulleys 18. Each cutaway portion 18a is in the form of a channel formed around the driven pulley 18. That is, the driven pulley 18 is reduced in diameter at the cutaway portion 18a. With this arrangement, attracting force can be applied to the printed paper through the cutaway portion 18a and the first vacuum hole 11a, and accordingly attracting force can be applied up to the driven pulleys 18, where conventionally no attracting force is applied to the printed paper. That is, attracting force can be applied up to the extreme discharge end of the transfer path, whereby the printed paper can be more surely conveyed and discharged. Reference numeral 19 in FIG. 3 denotes a kick roller which has a serrated peripheral edge as shown in FIG. 4 and ejects the printed paper toward the tray by pushing the trailing edge of the paper by the serrated peripheral edge thereof. Each kick roller 19 is mounted on the driven shaft 17 on the inner side of the driven pulley 18 and a part of the outer peripheral edge of the kick roller 19 projects upward above the conveyor belts 11. Though in this embodiment, the effective area which actually contributes to supplying suction force to the printed paper is made to be larger on the downstream side by increasing the widths of the second vacuum holes 13b, the effective area may be changed in other various manners. For example, it may be changed by changing the number of the second vacuum holes 13a which overlap with the first vacuum holes 11a at one time with the width of the second vacuum holes 13a kept uniform (e.g., by arranging so that one second vacuum hole 13b overlaps with one first vacuum hole 11a on the upstream side and a pair of second vacuum holes 13a overlap with one first vacuum hole 11a), or by changing the density of the second vacuum holes 13b. A second embodiment of the present invention will be described with reference to FIGS. 4 to 6, hereinbelow. In this embodiment, an air blower 20 is provided above the downstream side end portion of the transfer path. The air blower 20 comprises a fan 21 and an air guide pipe 22 whose air outlet port 22a is positioned just above the driven pulleys 18. When the fan 21 is operated, air above the fan 21 is taken in and blow over the driven pulleys 18 and the kick rollers 19 through the air outlet port 22a. Thus the printed paper on the conveyor belts 11 is pressed against the belts 11 by air blown from above through the air outlet port 22a. The air pressure together with the attracting force by the vacuum fan 12 causes the printed paper to surely receive the transfer force until its trailing edge is conveyed to the downstream end. Further, in this particular embodiment, since the air outlet port 22a is disposed just above the driven pulleys 18 and the kick roller 19, the trailing end portion of the printed paper is bent downward under the air pressure when the trailing end portion comes to the kick rollers 19 and accordingly the teeth 19a of the kick rollers 19 can be surely brought into engagement with the trailing edge of the printed paper, whereby the transfer force by the kick roller 19 can be surely transmitted to the printed paper and the printed paper can be discharged with a desirable transfer force. Though the second vacuum holes in the guide plate 13 are not shown in FIG. 6, the effective area which actually contributes to supplying suction force to the printed paper may be made to be larger on the downstream side in the manner described above in conjunction with the first embodiment, which is preferable, though not necessary, since the effect of the air blower and the effect of the biased attracting force distribution associate with each other. Further the driven pulleys 18 may be provided with the cutaway portions described above, though not necessary. A third embodiment of the present invention will be described with reference to FIGS. 7A and 7B. The sheet transfer system of this embodiment basically the same as that of the second embodiment except that the arrangement of the air blower is simplified. That is, though in the second embodiment, both the vacuum fan 12 and the air blower fan 21 are used, the vacuum fan 12 doubles as the air blower fan 21 in this embodiment, whereby the number of the parts is reduced, the structure is simplified and the overall size of the system is reduced. As shown in FIGS. 7A and 7B, there is provided a circulation passage 24 extending from below the vacuum fan 12 to above the conveyor belts 11. The circulation passage 24 is disposed, for instance, beside the conveyor belts 11 not to interfere with transfer of the printed paper to the tray 9. The upper open end of the circulation passage 24 forms an air outlet port 24a. The air outlet port 24a is positioned just above the downstream side end, more particularly just above the driven pulleys 18 and the kick rollers 19. When the vacuum fan 12 is operated, the printed paper is attracted against the conveyor belts 11 under the suction force generated by the vacuum fan 12 and at the same time air in the casing 14 is led upward through the circulation passage 24 to be blown downward through the air outlet port 24a. The printed paper on the conveyor belts 11 is pressed against the belts 11 by the air pressure as in the second embodiment. Though, in the embodiments described above, the sheet transfer system of the present invention is built in the printer body, the sheet transfer system of the present invention may be employed in other systems. For example, as shown in FIG. 8, the sheet transfer system of the present invention may be incorporated in a sorter 25 which is disposed beside the printer 1 to sort the printed papers discharged from the printer 1. The sorter 25 is provided with a plurality of trays or bins 26. The trays 26 are moved up and down by an up-and-down mechanism (not shown) and one of the trays 26 is selectively positioned near the sheet outlet port 10a of the sheet transfer system 10. The sheet transfer system 10 receives a printed sheet from the printer 1 and transfers the paper onto the tray placed near the sheet outlet port 10a. The sorter 25 may be of a known structure.
A sheet transfer system for transferring sheets on which an image is recorded by an image forming system and discharging the sheets to a tray includes a conveyor belt and a vacuum fan which generates a suction force for attracting the sheets against the conveyor belt. The suction force is stronger at the downstream side portion of the conveyor belt.
1
This application is the national phase of PCT/EP01/06359, filed Jun. 1, 2001, which claims the benefit of European Patent Application No. 00304809.7, filed Jun. 6, 2000. FIELD OF THE INVENTION The present invention pertains to a fluorinated resin and the use thereof in antifouling coating compositions for marine applications. BACKGROUND OF THE INVENTION Man-made structures such as boat hulls, buoys, drilling platforms, oil production rigs, and pipes which are immersed in water are prone to fouling by aquatic organisms such as green and brown algae, barnacles, mussels, and the like. Such structures are commonly of metal, but may also comprise other structural materials such as concrete. This fouling is a nuisance on boat hulls, because it increases frictional resistance during movement through the water, the consequence being reduced speeds and increased fuel costs. It is a nuisance on static structures such as the legs of drilling platforms and oil production rigs, firstly because the resistance of thick layers of fouling to waves and currents can cause unpredictable and potentially dangerous stresses in the structure, and, secondly, because fouling makes it difficult to inspect the structure for defects such as stress cracking and corrosion. It is a nuisance in pipes such as cooling water intakes and outlets, because the effective cross-sectional area is reduced by fouling, with the consequence that flow rates are reduced. The commercially most successful methods of inhibiting fouling have involved the use of anti-fouling coatings containing substances toxic to aquatic life, for example tributyltin chloride or cuprous oxide. Such coatings, however, are being regarded with increasing disfavour because of the damaging effects such toxins may have if released into the aquatic environment. There is accordingly a need for non-fouling coatings which do not contain markedly toxic materials. It has been known for many years, for example as disclosed in GB 1,307,001 and U.S. Pat. No. 3,702,778 that silicone rubber coatings resist fouling by aquatic organisms. It is believed that such coatings present a surface to which the organisms cannot easily adhere, and they can accordingly be called non-fouling rather than anti-fouling coatings. Silicone rubbers and silicone compounds generally have very low toxic properties. Silicone rubber coatings have, however, gained little commercial acceptance. It is difficult to make them adhere well to the substrate surface that is to be protected, and mechanically they are rather weak and liable to damage. It is known to use fluorinated polymers for fouling control in anti-fouling or non-fouling coating compositions. In JP 04-045170 a fluorinated silicone resin is disclosed which is obtained by grafting a fluorine-containing acrylate to a silicone resin having olefinically unsaturated bonds in its terminal groups. In JP 61-043668 a coating composition having antifouling properties is disclosed which is prepared by compounding an alkyd resin with a polymer prepared by reacting a fluorine-containing monomer with an acrylate polymer. In JP 06-322294 a corrosion protecting antifouling coating is disclosed comprising a film forming resin and an organopolysiloxane having oxyalkylene groups and perfluoroalkyl groups. Fluorinated polymers are also known for other uses. In JP 06-239876 a fluorinated polymer having excellent wetting properties is disclosed that is used in an adhesive. In U.S. Pat. No. 4,900,474 a perfluoroether group-containing organopolysiloxane is disclosed that is used as a silicone antifoamer. None of the fluorinated polymers that are known in the art have found wide application in antifouling coating compositions, since their anti-fouling/foul release properties are not sufficient and/or their mechanical properties do not make these compositions suited for use on various kind of structures that are immersed in water. In particular, the mechanical properties should be such that if applied as a coating composition for a boat hull, said coating composition should have sufficient strength and abrasion resistance to have a service life of several years. SUMMARY OF THE INVENTION The object of the present invention is to provide a new antifouling coating composition with very good anti-fouling/foul release properties and sufficient mechanical strength and a process for inhibiting the fouling of a substrate in a marine fouling environment wherein this new antifouling coating composition is used. This process comprises forming on a substrate, before exposure of the substrate to a marine fouling environment, a coating comprising a curable fluorinated resin of the general formula: W-L-YFC—O—R f —CFY-L-W  (I) wherein L is an organic linking group; Y is F or CF 3 ; W is a group of general formula —Si(R 1 ) α (OR 2 ) 3-α , wherein α=0, 1, or 2, preferably α=0, R 1 and R 2 independently have the meaning of linear or branched C1-C6 alkyl groups, optionally containing one or more ether groups, or C7-C12 aryl or alkyl groups, and preferably R 1 and R 2 are C1-C4 alkyl groups; R f is a group having an average molecular weight by number between 350 and 8000, preferably between 500 and 3000, and comprising repeating units having at least one of the following structures randomly distributed along the chain:  —CFXO—, —CF 2 CF 2 O—, —CF 2 CF 2 CF 2 O—, —CF 2 CF 2 CF 2 CF 2 O—, —CR 4 R 5 CF 2 CF 2 O—, —(CF(CF 3 )CF 2 O)—, —CF 2 CF(CF 3 )O—,  wherein X is F or CF 3 , R 4 and R 5 independently have the meaning of H, Cl, or C1-C4 perfluoroalkyl. DETAILED DESCRIPTION OF THE INVENTION In the curable fluorinated resin of the general formula: W-L-YFC—O—R f —CFY-L-W  (I) L is preferably a divalent linking group, more preferably L is selected from one or more of the following: a) —(CH 2 —(OCH 2 CH 2 ) n ) m —CO—NR′—(CH 2 ) q , wherein R′ is H, C 1 -C 4 alkyl or a phenyl group; m is an integer equal to 0 or 1, preferably 1; n is an integer in the range 0-8, preferably 0-5; q is an integer in the range 1-8, preferably 1-3; b) —CH 2 O—CH 2 CH 2 CH 2 — c) —CH 2 O—CH 2 —CH(OH)CH 2 —S—(CH 2 ) q L can also be a trivalent group. In this case in formula (I) -L-W becomes -L-(W) 2 . Preference is given to a compound wherein L is a) with m=1, n=0-5, and q=1-3. Further preference is given to R f being selected from one of the following structures: 1) —(CF 2 O) a′ —(C 2 F 4 O) b′ —, wherein a′/b′ is between 0.2 and 2, a′ and b′ being integers giving the above molecular weight; 2) —(C 3 F 6 O) r —(C 2 F 4 O) b —(CFXO) t —, wherein r/b is between 0.5 and 2 and (r+b)/t is between 10 and 30, b, r, and t being integers giving the above molecular weight; 3) —(C 3 F 6 O) r′ —(CFXO) t′ —CF 2 (R′f) y —CF 2 O—(CFXO) t′ —(C 3 F 6 O) r′ —, wherein t′ is larger than 0, r′/t′ is between 10 and 30, r′ and t′ being integers giving the above molecular weight, y is 0 or 1, and R′f is a C1-C4 fluoroalkyl group; 4) —(C 3 F 6 O) z —CF 2 —(R′f) y —CF 2 O—(C 3 F 6 O) z —, wherein z is an integer giving the above molecular weight, y is 0 or 1, and R′f is a C1-C4 fluoroalkyl group; 5) —(OCF 2 CF 2 CR 4 R 5 ) q —OCF 2 —(R′f) y —CF 2 O—(CR 4 R 5 CF 2 O) s —, wherein q and s are integers giving the above molecular weight, R 4 and R 5 have the meaning given above, y is 0 or 1, and R′f is a C1-C4 fluoroalkyl group. In the above structures —(C 3 F 6 O)— can be —(CF(CF 3 )CF 2 O)—or —(CF 2 CF(CF 3 )O)—. The product of formula (I) can be prepared by the method disclosed in U.S. Pat. No. 4,746,550. Good results in foul release and/or mechanical strength were found for a coating composition comprising the fluorinated resin of formula (I) that is obtainable by reacting a silicon compound, as defined below, with bifunctional perfluoropolyethers having —OH or —COOR end groups, with R═H or C1-C3 of the general formula: H—(OCH 2 CH 2 ) n —OCH 2 —CF 2 —O—R f —CF 2 —CH 2 O—(CH 2 CH 2 O) n —H  (II) or ROOC—CF 2 —O—R f —CF 2 —COOR  (III) wherein R f and n have the meaning as defined before. These compounds are commercially available from Ausimont under the names Fomblin® ZDOL, ZDEAL, ZDOL-TX. However, it is also possible to use bifunctional perfluoroethers having other end groups, e.g., epoxy groups Examples of suitable silicon compounds which can be reacted with the above bifunctional perfluoropolyether precursors are compounds of the general formula R 3 —Si—(R 4 ) 3   (IV) wherein R 3 is a group capable of coupling the silicon compound to the fluorinated polyether and the R 4 groups each independently have the meaning of an ether group, ester group, or preferably a group including a straight-chain or branched alkyl moiety having from 1 to 4 carbon atoms. For example, a silicon compound in which R 3 is an isocyanate-functional group can be coupled to a fluorinated polyether having at least two functional groups selected from hydroxyl, amine, or carboxylic acid-functional groups. A silicon compound in which R 3 is an amine-functional group can be coupled to a fluorinated polyether having at least two functional groups selected from carboxylic acid ester or epoxy-functional groups. A silicon compound in which R 3 is a thiol-functional group can be coupled to a fluorinated polyether having at least two epoxy-functional groups. Examples of preferred silicon compounds are alkoxyalkylsilyl isocyanates, alkoxysilyl alkyl isocyanates, alkoxy silanes, alkoxyalkyl silanes, and alkoxyalkylsilyl mercapto-, amino-, and glycidyl-functional compounds, such as 3-methyldimethoxy silylpropyl isocyanate, 3-trimethoxy silylpropyl isocyanate, 3-triethoxy silylpropyl isocyanate, 3-mercaptopropyl trimethoxy silane, 3-mercaptopropyl methyldimethoxy silane, 3-aminopropyl trimethoxy silane, 3-aminopropyl triethoxy silane, and 3-glycidoxypropyl trimethoxy silane. The thus obtained fluorinated resins are also the subject of the present invention. In general, good results in both anti/non-fouling properties and mechanical strength are found when the fluorinated resin has a T g in the range from −120 to 20° C. and a surface energy in the range from 10 to 25 mN/m. In general, mechanical properties improve when the T g of the resin is increased, foul release properties improve when the T g of the material is lowered. So, for each fluorinated resin an optimum balance has to be found between mechanical properties and foul release properties by tuning the T g of the resin. This tuning can, e.g., be done by varying the length of the R f segment or the W segment A coating composition can be prepared by mixing the fluorinated resin, a curing catalyst, for example a condensation catalyst, optionally a co-catalyst, optionally a crosslinker for the resin, a reactive or non-reactive fluid additive, solvents, fillers, pigments and/or thixotropes. Examples of catalysts that may be used include the carboxylic acid salts of various metals, such as tin, zinc, iron, lead, barium, and zirconium. The salts preferably are salts of long-chain carboxylic acids, for example dibutyltin dilaurate, dibutyltin dioctoate, iron stearate, tin (II) octoate, and lead octoate. Further examples of suitable catalysts include organobismuth and organotitanium compounds and organo-phosphates such as 2-ethyl-hexyl hydrogen phosphate. Other possible catalysts include chelates, for example dibutyltin acetoacetonate. Further, the catalyst may comprise a halogenated organic acid, which has at least one halogen substituent on a carbon atom which is in α-position relative to the acid group and/or at least one halogen substituent on a carbon atom which is in β-position relative to the acid group, or a derivative which is hydrolysable to form such an acid under the conditions of the condensation reaction. The presence of a cross-linker for the resin is only necessary if the resin cannot be cured by condensation. This depends on the functional groups that are present in the fluorinated resin. In general, when the fluorinated resin comprises alkoxy groups, the presence of a cross-linker is not necessary. If the fluorinated resin comprises alkoxy-silyl groups, in general the presence of a small amount of a condensation catalyst and water is sufficient to achieve full cure of the coating after application. For these compositions, normally atmospheric moisture is sufficient to induce curing and as a rule it will not be necessary to heat the coating composition after application. The crosslinker that is optionally present can be a cross-linking agent comprising a functional silane and/or one or more oxime groups. Examples of such cross-linking agents are presented in WO99/33927. Mixtures of different cross-linkers can also be used Examples of reactive or non-reactive fluid additives that can be used in the coating composition according to the present invention are non- or monofunctional fluorinated polyethers. These compounds can be represented by the following structure: T-O—CFY—O—R f —CFY-(L) k -T 1   (V) wherein k is an integer 0 or 1, T is selected from —CF 3 , —C 2 F 5 , —C 3 F 7 , CF 2 Cl, C 2 F 4 Cl, C 3 F 6 Cl, T 1 =—O-T when k=0, T 1 =W when k is 1. and wherein R f , Y, and L have the meaning as defined before. Commercial products are available from Ausimont, e.g. Fomblin® Y25. Other unreactive oils such as silicone oil, especially methyl-phenyl silicone oil, petrolatum, polyolefin oil, or a polyaromatic oil can also be used. The proportion of these reactive or non-reactive fluid additives may be in the range of from 0 to 25% by weight, based on the total weight of the coating composition. Examples of solvents that can be used in the coating composition according to the present invention include polar solvents or mixtures thereof, such as methyl isobutyl ketone or butyl acetate. Non-polar solvents or mixtures thereof, for example xylene, can be used as co-solvents Examples of fillers that can be used in the coating composition according to the present invention are barium sulphate, calcium sulphate, calcium carbonate, silicas or silicates (such as talc, feldspar, and china clay), aluminium paste/flakes, bentonite or other clays. Some fillers may have a thixotropic effect on the coating composition. The proportion of fillers may be in the range of from 0 to 25% by weight, based on the total weight of the coating composition. Examples of pigments that can be used in the coating composition according to the present invention are black iron oxide and titanium dioxide. The proportion of pigments may be in the range of from 0 to 10% by weight, based on the total weight of the coating composition. The coating composition can be applied by normal techniques, such as brush, roller or spray (airless and conventional). To achieve proper adhesion to the substrate it is preferred to apply the anti/non-fouling coating composition to a primed substrate. The primer can be any conventional primer/sealer coating system. Good results were found, in particular with respect to adhesion, when using a primer that comprises an acrylic siloxy-functional polymer, a solvent, a thixotropic agent, filler, and, optionally, a moisture scavenger. Such a primer is disclosed in WO 99/33927. It is also possible to apply the coating composition in the process according to the present invention on a substrate containing an aged anti-fouling coating layer. Before the coating composition is applied to such an aged layer, this old layer is cleaned by high-pressure water washing to remove any fouling. The primer disclosed in WO 99/33927 can be used as a tie coat between the aged coating layer and the coating composition according to the present invention. In general, low-surface energy coatings such as coatings comprising silicones or fluoropolymers do not provide a sound base for application of the coating composition according to the present invention, not even after the application of a tie-coat, since the adhesion between the aged coating layer and the freshly applied coating layer in general is insufficient. After the coating has been cured, it can be immersed immediately and gives immediate anti-fouling and fouling release protection. As indicated above, the coating composition used in the process according to the present invention has very good anti-fouling and foul release properties in combination with a high mechanical strength. This makes these coating compositions very suitable for use as anti-fouling or non-fouling coatings for marine applications. The coating can be used for both dynamic and static structures, such as boat hulls, buoys, drilling platforms, oil production rigs, and pipes which are immersed in water. The coating can be applied on any substrate that is used for these structures, such as metal, concrete, wood or fibre-reinforced resin. The coating compositions used in the process according to the present invention are preferably applied as high solids formulations. These compositions comprise less than 30% by weight of solvent, preferably less than 20%, still more preferably less than 10%. These formulations belong to the class of solventless coatings. Such coatings have minimal environmental impact in view of their low solvent content. The combination of low (ambient) temperature curing of the resins and high solids content of the coating composition makes the coating compositions according to the present invention suitable for application in the open field. The invention will be elucidated with reference to the following examples. These are intended to illustrate the invention, but are not to be construed as limiting in any manner the scope thereof. EXAMPLES Example 1 Preparation of an Adduct of a Perfluoroether 200 pbw of a bifunctional perfluoropolyether of formula (II) having n=0 and a number average molecular weight of 1000 were added to a flange-topped reaction vessel with a mechanical stirrer, a temperature probe, a water condenser, and a feed inlet. After the addition of 0.02 pbw of dibutyltin dilaurate (DBTDL), the reaction vessel was heated to 70° C. At this temperature, 88 pb of 3-(trimethoxysilylpropyl)isocyanate (TMSPI) were added dropwise over a two-hour period. During the addition the temperature was maintained at 70° C. using a temperature control unit. After the completion of the feed, the solution was stirred for another hour to complete the reaction. The progress of the reaction could be monitored by measuring the decrease of the infrared absorption of TMSPI at ˜2270 cm −1 . The adduct has a viscosity at 25° C. of 4.1 Poise (0.41 Pa.s) and a T g of −26° C. Example 2 Preparation of an Adduct of an Ethoxylated Perfluoroether Using the same process as described in Example 1, a bifunctional perfluoropolyether of formula (II) having n=1,5 and a number average molecular weight of 2000 was used as a perfluoroether starting component in the reaction. The formed adduct has a viscosity at 25° C. of 8.1 Poise (0.81 Pa.s) and a T g of −97°. Example 3 Using the process of Example 1, a perfluorinated adduct was obtained by a reaction between a bifunctional diester of formula (III) wherein R═CH 3 having a number average molecular weight of 2000 and an equimolar amount of 3-aminopropyl trimethoxysilane at 70° C. During the reaction methanol was removed by distillation until the ester IR-band at about 1800 cm −1 had disappeared completely. Example 4 A one-pack coating composition was prepared by combining 100 g of the adduct of a perfluoroether of Example 1 10 g of butyl acetate 0.2 g of 3-aminopropyl trimethoxy silane 0.1 g of dibutyltin dilaurat After application of this coating composition on a wooden substrate and curing of the composition, a coating was obtained with a modulus at 20° C. of 42.5 Mpa (measured in accordance with ASTM D1708) and a pencil hardness of 3H (measured in accordance with ASTM D3363) Example 5 A one-pack coating composition was prepared by combining 100 g of the adduct of a perfluoroether of Example 1 20 g of butyl acetate 0.2 g of 3-aminopropyl trimethoxy silane 0.1 g of dibutyltin dilaurate 3 g of Fomblin Y-25 (a perfluorinated polyether, ex Ausimont) Example 6 A two-pack coating composition was prepared by having 100 g of the adduct of a perfluoroether of Example 2 in one pack and combining 10 g of butyl acetate 0.2 g of 3-aminopropyl trimethoxy silane 0.1 g of dibutyltin dilaurate in the other pack. After application of this coating composition on a wooden substrate and curing of the composition, a coating was obtained with a modulus at 20° C. of 3.1 Mpa (measured in accordance with ASTM D1708) and a pencil hardness of 4B (measured in accordance with ASTM D3363 Example 7 A one-pack coating composition was prepared by combining 100 g of the adduct of a perfluoroether of Example 1 10 g of butyl acetate 0.2 g of 3-aminopropyl trimethoxy silane 0.1 g of dibutyltin dilaurate 30 g of talc 6 g of black iron oxide 25 g of aluminium flake Example 8 A one-pack coating composition was prepared by combining 100 g of the adduct of a perfluoroether of Example 2 20 g of butyl acetate 1 g of 2-ethylhexylhydrogen phosphate 3 g of Fomblin Y-25 (a perfluorinated polyether, ex Ausimont) The coating compositions of Examples 4-8 were applied to wood substrates bearing an anti-corrosive undercoat and coating primers as disclosed in WO 99/33927. The coating formulations were applied by brush and roller to give a layer of average dry film thickness in the range from 25 to 75 μm. For static anti-fouling assessment the coated substrates were immersed in a marine estuary known for its weed, slime, hard-shelled and soft-bodied animal fouling. After one season (February-October) the accumulated fouling was significantly less than that of control substrates not coated with the compositions and maintained under the same conditions over the same period of time. Any fouling on the substrates with the compositions of Examples 4-8 could be removed easily by light rubbing or low-pressure water jet. Accumulated fouling on the control substrates immersed over the same period could not be removed in a similar way. For these coating compositions the following quantitative fouling properties were found: % Exam- % micro soft-bodied % hard-bodied % total Push-off ple fouling animal animal fouling (PSI)* 4 25 1.7 56.7 83.4 20.55 5 23.8 3.5 41.3 68.6 11.04 6 28.8 2.2 50 81 13.34 7 19.7 2.2 6.8 28.7 6.24 8 51.4 4.2 22.4 78 9.11 *Measured in accordance with ASTM standard D-5618, barnacle type Semibalanus Balanoides Example 9 A coating composition was prepared by combining 100 g of the adduct of a perfluoroether of Example 3 20 g of butyl acetate 1 g of 2-ethylhexylhydrogen phosphate 3 g of Fomblin Y-04 (a perfluorinated polyether, ex Ausimont) Example 10 A coating composition was prepared by combining 100 g of the adduct of a perfluoroether of Example 2 20 g of butyl acetate 15 g of titaniumdioxide 1 g of 2-ethylhexylhydrogen phosphate 6 g of Fomblin Y-25 (a perfluorinated polyether, ex Ausimont) The coating compositions of Examples 9 and 10 were applied to wood substrates bearing an anti-corrosive undercoat and coating primers as disclosed in WO 99/33927. The coating formulations were applied by brush and roller to give a layer of average dry film thickness in the range from 25 to 75 μm. For static anti-fouling assessment the coated substrates were immersed in a marine estuary known for its weed, slime, hard-shelled and soft-bodied animal fouling.
A process for inhibiting the fouling of a substrate in a marine fouling environment, which comprises forming on the substrate, before exposure to the said environment, a coating comprising a curable fluorinated resin of the general formula: W-L-YFC—O—R f —CFY-L-W wherein: W is a group of the general formula —Si(R 1 ) α (OR 2 ) 3-α , wherein α=0, 1, or 2, preferably α=0, R 1 and R 2 independently have the meaning of linear of branched C 1 -C 6 alkyl groups, optionally containing one or more ether groups, or C 7 -C 12 aryl or alkyl groups, and preferably R 1 and R 2 are C1-C4 alkyl groups; L is an organic linking group; Y is F or CF 3 ; and R f is a group having an average molecular weight by number between 350 and 8000, preferably between 500 and 3000, and comprising repeating units having at least one of the following structures randomly distributed along the chain: —CFXO—, CF 2 CF 2 O—, CF 2 CF 2 CF 2 O—, CF 2 CF 2 CF 2 CF 2 O—, CR 4 R 5 CF 2 CF 2 O—, —(CF(CF 3 )CF 2 O)—, —CF 2 CF(CF 3 )O—, wherein X is F or CF 3 , R 4 and R 5 independently have the meaning of H, Cl, or C1-C4 perfluoroalkyl.
2
BACKGROUND There are many types of systems that allow users to share files. For instance, in some collaboration systems, a plurality of different users can access one or more different note taking applications and set up notebooks where the users can modify, contribute to, and share, information. The notebooks may have sections or folders, each of which contains a variety of different files. In these types of collaborative or shared systems, multiple clients or users can be working on a folder in a shared location, such as a network share location or on a web server. It is also common in these types of shared systems for an entire notebook, folder, or portions of a folder, to be moved to a new location. When this occurs, other clients may attempt to write data to the old location, without being informed that the working set (the notebook, folder, etc.) has been moved to the new location. In addition, where multiple files are to be moved (such as where an entire folder is to be moved) the client may access the notebook when the folder has only been partially moved to the new location. Similarly, some clients may be offline when the move is initiated, so even if some type of notification system is in place that notifies clients that a folder is to be moved, the offline clients will not be notified of the move in a synchronous way. Some have attempted to address this problem by relying on the server to send messages. In such a system, the server is required to keep sending messages to notify clients of the change of location. However, this often requires changes to both the server and client which may not be feasible. Similarly, this does not support older clients that have already been released. Still others have attempted to address this problem by manually generating electronic mail (or other messages) to the clients that work on the shared system. However, this often requires a person to accurately generate electronic mail messages to all users. This is cumbersome and can also be error prone. The discussion above is merely provided for general background information and is not intended to be used as an aid in determining the scope of the claimed subject matter. SUMMARY A client device accesses a shared data system and begins moving data from one location to another. The client device generates a tombstone object that includes metadata indicating that the data has been moved. When another client accesses the data at the old location, it encounters the tombstone and begins accessing the data at the new location. If the data has not already been completely moved to the new location, the second client to access the data assists in transferring the data to the new location. This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter. The claimed subject matter is not limited to implementations that solve any or all disadvantages noted in the background. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram of one illustrative data system. FIG. 2 illustrates user devices that can transmit data from an old location to a new location. FIG. 3 shows one embodiment of a tombstone. FIG. 4 shows another embodiment of a tombstone. FIG. 5 is a flow diagram illustrating one embodiment of the operation of the system shown in FIG. 1 in moving data. FIGS. 5A-5D are illustrative user interface displays. FIG. 6 shows various architectures in which the system of FIG. 1 can be employed. FIGS. 7-11 illustrate various embodiments of mobile devices. FIG. 12 shows an illustrative computing environment. DETAILED DESCRIPTION FIG. 1 is a block diagram of a data system 100 . Data system 100 includes data collaboration system (or shared data system) 102 and data collaboration system (or shared data system) 104 . User devices (or clients) 106 and 108 are coupled to data collaboration systems 102 and 104 either directly (as indicated by arrows 110 and 112 ) or through a network 114 . In the embodiment shown, users 116 and 118 access systems 102 and 104 , using user devices 106 and 108 . FIG. 1 also shows that each user device 106 and 108 has a data move component 120 and 122 , respectively. In the embodiment shown in FIG. 1 , data collaboration system 102 includes data store 124 that has a plurality of notebooks 126 and 128 . Each notebook has at least one folder 130 and 132 , and each folder has one or more files 136 and 138 , respectively. System 102 also includes one or more note taking applications 140 and 142 that generate user interfaces for display on user devices 106 and 108 , using user interface component 144 . Note taking applications 140 and 142 maintain the notebooks 126 and 128 in data store 124 , and the user interfaces allow users 116 and 118 to collaborate (such as to add, delete, modify, create, save, etc.) or shared data in the files or folders of notebooks 126 and 128 . It will be appreciated that each notebook, itself, could be a folder, while each section could be a file. Folders and files can be configured in other ways as well, where a folder contains one or more files. The folder construct can be named other things such as a notebook, a section, a collection, a notepad or other things. In fact, while the data collaboration system described herein discusses note taking applications with notebooks, this is exemplary only. Other shared data systems can be used as well, or instead. The present discussion is provided with a notebook having section folders for the sake of example only. In the embodiment shown in FIG. 1 , data collaboration system 102 also includes processor 146 . In one embodiment, processor 146 is a computer processor with associated memory and timing circuitry (not shown). Processor 146 is illustratively a functional component of system 102 and is activated by, and facilities the functionality of, the various other applications and components in system 102 . FIG. 1 shows that data collaboration system 104 is similar to data collaboration system 102 , in that it includes a data store with notebooks and section folders that each contain files. More specifically, it includes a data store 150 that includes notebooks 152 and 154 , each of which include section folders 156 and 158 . Folders 156 and 158 also each include files 160 and 162 . System 104 also includes a plurality of note taking applications 164 and 166 , along with a user interface component 168 and processor 170 . It will be noted that while systems 102 and 104 are shown with note taking applications, this is shown by way of example only. They could be provided with substantially any other type of data collaboration systems or shared data systems that allow a plurality of different users to collaborate on, or share, stored data. In one embodiment, one of the users uses his or her client device to initiate a move of a folder from one location in either system 102 or 104 to another location. For the sake of the present discussion, it will be assumed that user 116 wishes to initiate a move of folder 132 from its current location in data store 124 in data collaboration system 102 to a new location in data store 150 in data collaboration system 104 . User 116 does this by using data move component 120 in user device 106 . Moving folder 132 is indicated by arrow 172 in FIG. 1 . FIG. 2 is a simplified block diagram of system 100 (shown in FIG. 1 ), and similar items are similarly numbered. However, FIG. 2 shows user devices 106 and 108 in more detail. Specifically, FIG. 2 shows that user devices 106 and 108 each have a processor 121 and 125 that is a functional component of its device and is activated by, and facilitates the functionality of, other applications and components of its corresponding device 106 and 108 . FIG. 2 also shows that devices 106 and 108 each have a UI component 123 and 127 , respectively, for generating user interface displays with user input mechanisms for receiving user inputs, and client applications 129 and 131 that can be client components of the note taking applications 140 , 142 , 164 and 166 or other applications. The operation of data move component 120 in initiating a move of folder 132 from its old location 180 in system 102 to its new location 182 in system 104 is described in greater detail below with respect to FIGS. 5-5D . Briefly, before describing the operation in detail, the user 116 indicates that he or she wishes to move folder 132 from the old location 180 to the new location 182 . This is illustratively done by device 106 generating a suitable user interface display using user interface component 123 that displays user input mechanisms that allow user 116 to interact with data move component 120 . In response to user 116 indicating that he or she wishes to move folder 132 to its new location 182 , data move component 120 generates a tombstone 184 at the old location, and then begins moving the files in folder 132 to new location 182 . In one embodiment, tombstone 184 includes metadata that can be read by client application 129 or 131 on a user device that attempts to access folder 132 at the old location, after the move has been initiated. One embodiment of tombstone 184 is illustrated in FIG. 3 . It can be seen in FIG. 3 that the embodiment of tombstone 184 includes a metadata portion 186 and a human readable portion 188 . Metadata portion 186 illustratively includes an identity of new location identifier 190 that identifies the new location 182 , time and date information 192 that indicate the time and date that the move was initiated, a user identifier 194 that identifies the user that initiated the move, and a status indicator 196 that indicates whether the move has been completed, or whether it is in process. Of course, metadata in portion 186 can include other data 198 as well. The embodiment shown in FIG. 3 illustrates that the human readable data portion 188 in tombstone 184 includes a message that can be displayed to another user that attempts to access folder 132 in the old location 180 . In one embodiment, where the user's device is not equipped with a version of the client application 129 , 131 that can read metadata in metadata portion 186 , the message in human readable data portion 188 is displayed to the user. In the embodiment shown in FIG. 3 , the human readable data simply states “This notebook has been moved. Click the link below to open the notebook.” Human readable data portion 188 includes an actuatable link 200 which, when actuated by the user, navigates the user to the new location of the notebook or folder 132 . FIG. 4 is another embodiment of a tombstone 202 which is similar to tombstones 184 shown in FIG. 3 , and similar items are similarly numbered. However, for the embodiment shown in FIG. 4 , the entire folder 132 has not yet been moved to its new location, but instead the move is still in progress. Therefore, the information in status indicator 196 will indicate that the move is still in progress, and the human readable message will be changed to indicate this as well. In the embodiment shown in FIG. 4 , the human readable message states “This notebook is being moved. Click on the link below to open the notebook at its new location.” Of course, these are exemplary embodiments of tombstone 184 and 200 , and others could be generated as well. FIG. 5 is a flow diagram illustrating the operation of user devices 106 and 108 in moving folder 132 from its old location 180 in system 102 to its new location 182 in system 104 , in greater detail. FIGS. 5A-5D are illustrative user interface displays that are generated by the user interface components 123 and 127 and allow a user to initiate the move of a folder. FIGS. 5-5D will now be described in conjunction with one another. The description will proceed with respect to user 116 initiating a move with user device 106 . However, this is, of course, exemplary only and other users can initiate the move as well. User 116 first provides an input, through a suitable user input mechanism generated by UI component 123 , indicating that the user wishes to access folder 132 . Then, in one embodiment, client application 129 generates a user interface display, using UI component 123 , such as user interface display 300 shown in FIG. 5A . User interface display 300 shows a variety of different information corresponding to a notebook whose name is displayed in a text box 302 . The location of the given notebook is also indicated at location display portion 304 . In addition, the author of the notebook and the various other users of the notebook, for example, are indicated generally at 306 . Accessing the desired data (in this case folder 132 ) is indicated by block 399 in FIG. 5 . In the embodiment shown in FIG. 5A , the user is provided with a delete button 308 and a move button 310 . Delete button 308 allows the user to delete a notebook or other data while move button 310 allows the user to initiate the move of a notebook, or a portion of the notebook, to a new location. The user 116 illustratively actuates button 310 . This can be done in a wide variety of different ways. For instance, where the display screen of user device 106 is a touch sensitive display screen, the user 116 can actuate button 310 simply by touching it either with the user's finger or with a stylus or with another item. Of course, the user 116 can also actuate button 310 in other ways, such as by using a point and click device, by using voice commands, by using other touch gestures, etc. This input is provided to data move component 120 which is then initiated to begin moving folder 132 from old location 180 to new location 182 . Having the client initiate the move is indicated by block 400 in FIG. 5 . As the client is attempting to initiate the move at block 400 , it may be desirable to ask the user for credentials or authorization to ensure that this particular user has the authority to move the folder. This can be done as well. FIG. 5B shows an alternative user interface display 320 . Display 320 allows a user to choose a notebook using a suitable user input mechanism, such as dropdown menu 324 . Once the user has chosen the notebook, the location for that notebook is indicated generally at 326 . Display 320 also provides a plurality of buttons 328 that allow the user to perform certain actions with respect to the notebook displayed in dropdown menu 324 . Among the buttons 328 are move button 330 and delete button 332 . When the user actuates delete button 332 , the user can delete the notebook. If the user actuates button 330 , the user can initiate a move of the notebook from its current location to a new location. Once a move has been initiated, data move component 120 generates tombstone 184 at the old location of folder 132 . This is indicated by block 402 in FIG. 5 . Recall that two exemplary embodiments of tombstones are described above with respect to FIGS. 3 and 4 . Once the tombstone is generated by data move component 120 , it is stored in the old location 180 , and this is indicated by block 404 . User device 106 then generates a user interface display using component 123 that allows the user to input the identity of the new location for the file to be moved. FIG. 5C shows one embodiment of a user interface display 340 that has some similar items to user interface display 320 shown in FIG. 5B , and those items are similarly numbered. User interface display 340 shows some new locations that can be selected by the user, and these are generally indicated at 342 . In the embodiment shown in FIG. 5C , the new locations 342 are listed in a new locations list 344 that includes a plurality of different portions. List 344 is shown broken out by general location, such as a location corresponding to a given project (in this case Contoso Landscaping) shown at 346 , an individual user's cloud site 348 and a general computer location 350 . If the user selects one of items 346 , 348 and 350 , the list corresponding to the selected item expands. In the embodiment shown in FIG. 5C , the user has selected the Contoso Landscaping item 346 . Therefore, the locations corresponding to that item are divided into two sections including a recent libraries section 352 and a team sites section 354 . This list is also scrollable using a scroll bar 356 . Therefore, the user can scroll through different possible new locations and select one of them. Once the new location is selected, it is listed in a new location text box 358 and the user can begin the move by pressing move button 360 . Receiving a user input indicative of the identity of the new location is indicated by block 406 in FIG. 5 . It will of course be appreciated that the described way of selecting a new location is exemplary only and a wide variety of other ways, other users input mechanisms and other displays can be used as well. Once the new location is input or chosen by the user, the tombstone ( 184 or 202 ) is updated with a link to that new location and the tombstone metadata is updated to indicate that location as well. Of course, in another embodiment, the tombstone ( 184 or 202 ) is not created and stored in the old location until after the user has input or chosen the new location and actuated move button 360 . The present description is exemplary only. Once the user has actuated move button 360 , data move component 120 selects one of the files in folder 132 and moves the selected files from the old location 180 to the new location 182 . Selecting a file and moving the file are indicated by blocks 408 and 410 in FIG. 5 . Data move component 120 then determines whether there are more files to be moved, at block 412 . If so, processing reverts to block 408 where component 120 selects another file to be moved and moves that file. It will be appreciated that, as long as there are still files to be moved in the selected folder 132 , the tombstone stored at the old location will be tombstone 202 and will indicate the new location of folder 132 , the time and date that the move was initiated, the user who initiated the move, and the status indicator 196 will indicate that the move is still in progress. Human readable data 188 will indicate this as well. However, if, at block 412 , it is determined that all of the files have been moved, then data move component 120 modifies the tombstone 202 to be tombstone 184 and to indicate that the move has been completed. This is done by illustratively modifying the status indicator 196 and the human readable data 188 to indicate that the move has been completed. This is indicated by block 414 in FIG. 5 . It will also be appreciated that, while the move is in process, data move component 120 may lock the files in folder 132 during the move. Any changes by a client or other user device will be held locally on that client or user device until the move has been completed. During the move, data move component 120 can generate a progress bar display such as that shown in user interface display 380 in FIG. 5D . The progress bar display 380 illustratively shows the new location for the notebook (or folder) at 382 and provides a status bar 384 that indicates the progress of the move to the new location. Once the move has been completed, data move component 120 modifies application 129 so that the location of the working set (in this case folder 132 ) is set to the new location 182 . This is indicated by block 416 in FIG. 5 . Any pending changes that have been made during the move are then written to the working set at the new location 182 . This is indicated by block 418 in FIG. 5 . It may happen that, either during the move of folder 132 or after it, a different client device (such as user device 108 ) attempts to access folder 132 at the old location 180 . Because the user device 108 itself has a data move component 122 , user device 108 will discover the tombstone ( 184 or 202 ) at the old location. Having device 108 attempt to access the folder at the old location 180 and having it subsequently discover tombstone ( 184 or 202 ) is indicated by blocks 420 and 422 in FIG. 5 . In an embodiment where data move component 122 is configured to read the metadata in metadata portion 186 of tombstone 184 or 202 , data move component 122 can read the status indicator 196 to determine whether the move has been completed. This is indicated by blocks 424 and 426 in FIG. 5 . If not, then data move component 122 , itself, begins to assist in moving folder 132 from its old location 180 to the new location 182 . In doing so, data move component 122 of user device 108 begins processing at block 408 discussed above. Thus, data move component 122 on user device 108 selects a file to be moved and moves the selected file and then determines whether there are still more files to be moved. This is indicated by blocks 408 , 410 and 412 . This continues until there are no more files to be moved (at which point the move is complete) or until device 108 is off line (in which case it stops helping with the move). The particular data move component 120 or 122 that moves the last file updates the status indicator 196 in tombstone 202 to indicate that the move is now complete. Processing then continues at blocks 414 , 416 and 418 . Once the files in folder 132 have been completely moved, it may be desirable to delete them from the old location as well. Therefore, the data move component that moves the last file may optionally delete the old files from the old location. It may happen that a particular data move component 120 or 122 is not configured to read the metadata in the tombstone 184 or 202 . This may happen, for instance, where the particular data move component is an older version or has simply not been setup to read the metadata. In that case, at block 424 , the given user device 108 will simply display the human readable data from tombstone 184 or 202 to the user. This is indicated by block 430 in FIG. 5 . Thus, the user will see the displayed message “This notebook has been moved. Click the link below to open the notebook.” (where the move has been completed). Alternatively, if the move has not yet been completed, the user will be shown the message illustrated in FIG. 4 which states “This notebook is being moved. Click on the link below to open the notebook at its new location.” Of course, these are exemplary messages only and others could be used as well. FIG. 6 is a block diagram of system 100 , shown in various architectures, including cloud computing architecture 500 . Cloud computing provides computation, software, data access, and storage services that do not require end-user knowledge of the physical location or configuration of the system that delivers the services. In various embodiments, cloud computing delivers the services over a wide area network, such as the internet, using appropriate protocols. For instance, cloud computing providers deliver applications over a wide area network and they can be accessed through a web browser or any other computing component. Software or components of system 100 as well as the corresponding data, can be stored on servers at a remote location. The computing resources in a cloud computing environment can be consolidated at a remote data center location or they can be dispersed. Cloud computing infrastructures can deliver services through shared data centers, even though they appear as a single point of access for the user. Thus, the components and functions described herein can be provided from a service provider at a remote location using a cloud computing architecture. Alternatively, they can be provided from a conventional server, or they can be installed on client devices directly, or in other ways. The description is intended to include both public cloud computing and private cloud computing. Cloud computing (both public and private) provides substantially seamless pooling of resources, as well as a reduced need to manage and configure underlying hardware infrastructure. A public cloud is managed by a vendor and typically supports multiple consumers using the same infrastructure. Also, a public cloud, as opposed to a private cloud, can free up the end users from managing the hardware. A private cloud may be managed by the organization itself and the infrastructure is typically not shared with other organizations. The organization still maintains the hardware to some extent, such as installations and repairs, etc. The embodiment shown in FIG. 6 , specifically shows that system 100 is located in cloud 502 (which can be public, private, or a combination where portions are public while others are private). Therefore, user 116 uses a user device, such as user device 106 , to access those systems through cloud 502 . FIG. 6 also depicts another embodiment of a cloud architecture. FIG. 6 shows that it is also contemplated that some elements of system 100 are disposed in cloud 502 while others are not. By way of example, data store 124 can be disposed outside of cloud 502 , and accessed through cloud 502 . In another embodiment, some or all of the components of system 100 (such as note taking application 140 or other portions) are also outside of cloud 502 . Regardless of where they are located, they can be accessed directly by device 106 , through a network (either a wide area network or a local area network), they can be hosted at a remote site by a service, or they can be provided as a service through a cloud or accessed by a connection service that resides in the cloud. All of these architectures are contemplated herein. FIG. 6 further shows that some or all of the portions of system 100 can be located on device 106 . It will also be noted that system 100 , or portions of it, can be disposed on a wide variety of different devices. Some of those devices include servers, desktop computers, laptop computers, tablet computers, or other mobile devices, such as palm top computers, cell phones, smart phones, multimedia players, personal digital assistants, etc. FIG. 7 is a simplified block diagram of one illustrative embodiment of a handheld or mobile computing device that can be used as a user's or client's hand held device 16 , in which the present system (or parts of it) can be deployed. In one embodiment, device 16 can comprise one or more of user devices 106 or 108 but it can also comprise a collaboration system 102 or 104 as well. FIGS. 7-11 are examples of handheld or mobile devices. FIG. 7 provides a general block diagram of the components of a client device 16 that can run components of system 100 or that interacts with system 100 , or both. In the device 16 , a communications link 13 is provided that allows the handheld device to communicate with other computing devices and under some embodiments provides a channel for receiving information automatically, such as by scanning. Examples of communications link 13 include an infrared port, a serial/USB port, a cable network port such as an Ethernet port, and a wireless network port allowing communication though one or more communication protocols including General Packet Radio Service (GPRS), LTE, HSPA, HSPA+ and other 3G and 4G radio protocols, 1×rtt, and Short Message Service, which are wireless services used to provide cellular access to a network, as well as 802.11 and 802.11b (Wi-Fi) protocols, and Bluetooth protocol, which provide local wireless connections to networks. Under other embodiments, applications or systems (like system 100 ) are received on a removable Secure Digital (SD) card that is connected to a SD card interface 15 . SD card interface 15 and communication links 13 communicate with a processor 17 (which can also embody one of processors 146 , 170 , 121 or 125 from FIGS. 1 and 2 ) along a bus 19 that is also connected to memory 21 and input/output (I/O) components 23 , as well as clock 25 and location system 27 . I/O components 23 , in one embodiment, are provided to facilitate input and output operations. I/O components 23 for various embodiments of the device 16 can include input components such as buttons, touch sensors, multi-touch sensors, optical or video sensors, voice sensors, touch screens, proximity sensors, microphones, tilt sensors, and gravity switches and output components such as a display device, a speaker, and or a printer port. Other I/O components 23 can be used as well. Clock 25 illustratively comprises a real time clock component that outputs a time and date. It can also, illustratively, provide timing functions for processor 17 . Location system 27 illustratively includes a component that outputs a current geographical location of device 16 . This can include, for instance, a global positioning system (GPS) receiver, a LORAN system, a dead reckoning system, a cellular triangulation system, or other positioning system. It can also include, for example, mapping software or navigation software that generates desired maps, navigation routes and other geographic functions. Memory 21 stores operating system 29 , network settings 31 , applications 33 , application configuration settings 35 , data store 37 , communication drivers 39 , and communication configuration settings 41 . Memory 21 can include all types of tangible volatile and non-volatile computer-readable memory devices. It can also include computer storage media (described below). Memory 21 stores computer readable instructions that, when executed by processor 17 , cause the processor to perform computer-implemented steps or functions according to the instructions. System 100 or the items in data store 124 , for example, can reside in memory 21 . Similarly, device 16 can have a client business system 24 which can run various applications (such as application 140 or 129 ) or embody parts or all of system 100 . Processor 17 can be activated by other components to facilitate their functionality as well. Examples of the network settings 31 include things such as proxy information, Internet connection information, and mappings. Application configuration settings 35 include settings that tailor the application for a specific enterprise or user. Communication configuration settings 41 provide parameters for communicating with other computers and include items such as GPRS parameters, SMS parameters, connection user names and passwords. Applications 33 can be applications (such as application 140 or 129 ) that have previously been stored on the device 16 or applications that are installed during use, although these can be part of operating system 29 , or hosted external to device 16 , as well. FIG. 8 and show one embodiment in which device 16 is a tablet computer 600 . In FIG. 8 , computer 600 is shown with display screen 602 showing the display of FIG. 3 while FIG. 9 shows computer 600 with display screen 602 showing the display of FIG. 5B . Screen 602 can be a touch screen (so touch gestures from a user's finger 604 can be used to interact with the application) or a pen-enabled interface that receives inputs from a pen or stylus. It can also use an on-screen virtual keyboard. Of course, it might also be attached to a keyboard or other user input device through a suitable attachment mechanism, such as a wireless link or USB port, for instance. Computer 600 can also illustratively receive voice inputs as well. FIGS. 10 and 11 provide additional examples of devices 16 that can be used, although others can be used as well. In FIG. 10 , a smart phone or mobile phone 45 is provided as the device 16 . Phone 45 includes a set of keypads 47 for dialing phone numbers, a display 49 capable of displaying images including application images, icons, web pages, photographs, and video, and control buttons 51 for selecting items shown on the display. The phone includes an antenna 53 for receiving cellular phone signals such as General Packet Radio Service (GPRS) and 1×rtt, and Short Message Service (SMS) signals. In some embodiments, phone 45 also includes a Secure Digital (SD) card slot 55 that accepts a SD card 57 . The mobile device of FIG. 11 is a personal digital assistant (PDA) 59 or a multimedia player or a tablet computing device, etc. (hereinafter referred to as PDA 59 ). PDA 59 includes an inductive screen 61 that senses the position of a stylus 63 (or other pointers, such as a user's finger) when the stylus is positioned over the screen. This allows the user to select, highlight, and move items on the screen as well as draw and write. PDA 59 also includes a number of user input keys or buttons (such as button 65 ) which allow the user to scroll through menu options or other display options which are displayed on display 61 , and allow the user to change applications or select user input functions, without contacting display 61 . Although not shown, PDA 59 can include an internal antenna and an infrared transmitter/receiver that allow for wireless communication with other computers as well as connection ports that allow for hardware connections to other computing devices. Such hardware connections are typically made through a cradle that connects to the other computer through a serial or USB port. As such, these connections are non-network connections. In one embodiment, mobile device 59 also includes a SD card slot 67 that accepts a SD card 69 . Note that other forms of the devices 16 are possible. FIG. 12 is one embodiment of a computing environment in which system 100 (for example) can be deployed. With reference to FIG. 12 , an exemplary system for implementing some embodiments includes a general-purpose computing device in the form of a computer 810 . Components of computer 810 may include, but are not limited to, a processing unit 820 (which can comprise processor 146 , 170 , 121 or 125 ), a system memory 830 , and a system bus 821 that couples various system components including the system memory to the processing unit 820 . The system bus 821 may be any of several types of bus structures including a memory bus or memory controller, a peripheral bus, and a local bus using any of a variety of bus architectures. By way of example, and not limitation, such architectures include Industry Standard Architecture (ISA) bus, Micro Channel Architecture (MCA) bus, Enhanced ISA (EISA) bus, Video Electronics Standards Association (VESA) local bus, and Peripheral Component Interconnect (PCI) bus also known as Mezzanine bus. Memory and programs described with respect to FIG. 12 can be deployed in corresponding portions of FIG. 12 . Computer 810 typically includes a variety of computer readable media. Computer readable media can be any available media that can be accessed by computer 810 and includes both volatile and nonvolatile media, removable and non-removable media. By way of example, and not limitation, computer readable media may comprise computer storage media and communication media. Computer storage media is different from, and does not include, a modulated data signal or carrier wave. It includes hardware storage media including both volatile and nonvolatile, removable and non-removable media implemented in any method or technology for storage of information such as computer readable instructions, data structures, program modules or other data. Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile disks (DVD) or other optical disk storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to store the desired information and which can be accessed by computer 810 . Communication media typically embodies computer readable instructions, data structures, program modules or other data in a transport mechanism and includes any information delivery media. The term “modulated data signal” means a signal that has one or more of its characteristics set or changed in such a manner as to encode information in the signal. By way of example, and not limitation, communication media includes wired media such as a wired network or direct-wired connection, and wireless media such as acoustic, RF, infrared and other wireless media. Combinations of any of the above should also be included within the scope of computer readable media. The system memory 830 includes computer storage media in the form of volatile and/or nonvolatile memory such as read only memory (ROM) 831 and random access memory (RAM) 832 . A basic input/output system 833 (BIOS), containing the basic routines that help to transfer information between elements within computer 810 , such as during start-up, is typically stored in ROM 831 . RAM 832 typically contains data and/or program modules that are immediately accessible to and/or presently being operated on by processing unit 820 . By way of example, and not limitation, FIG. 12 illustrates operating system 834 , application programs 835 , other program modules 836 , and program data 837 . The computer 810 may also include other removable/non-removable volatile/nonvolatile computer storage media. By way of example only, FIG. 12 illustrates a hard disk drive 841 that reads from or writes to non-removable, nonvolatile magnetic media, a magnetic disk drive 851 that reads from or writes to a removable, nonvolatile magnetic disk 852 , and an optical disk drive 855 that reads from or writes to a removable, nonvolatile optical disk 856 such as a CD ROM or other optical media. Other removable/non-removable, volatile/nonvolatile computer storage media that can be used in the exemplary operating environment include, but are not limited to, magnetic tape cassettes, flash memory cards, digital versatile disks, digital video tape, solid state RAM, solid state ROM, and the like. The hard disk drive 841 is typically connected to the system bus 821 through a non-removable memory interface such as interface 840 , and magnetic disk drive 851 and optical disk drive 855 are typically connected to the system bus 821 by a removable memory interface, such as interface 850 . The drives and their associated computer storage media discussed above and illustrated in FIG. 12 , provide storage of computer readable instructions, data structures, program modules and other data for the computer 810 . In FIG. 12 , for example, hard disk drive 841 is illustrated as storing operating system 844 , application programs 845 , other program modules 846 , and program data 847 . Note that these components can either be the same as or different from operating system 834 , application programs 835 , other program modules 836 , and program data 837 . Operating system 844 , application programs 845 , other program modules 846 , and program data 847 are given different numbers here to illustrate that, at a minimum, they are different copies. A user may enter commands and information into the computer 810 through input devices such as a keyboard 862 , a microphone 863 , and a pointing device 861 , such as a mouse, trackball or touch pad. Other input devices (not shown) may include a joystick, game pad, satellite dish, scanner, or the like. These and other input devices are often connected to the processing unit 820 through a user input interface 860 that is coupled to the system bus, but may be connected by other interface and bus structures, such as a parallel port, game port or a universal serial bus (USB). A visual display 891 or other type of display device is also connected to the system bus 821 via an interface, such as a video interface 890 . In addition to the monitor, computers may also include other peripheral output devices such as speakers 897 and printer 896 , which may be connected through an output peripheral interface 895 . The computer 810 is operated in a networked environment using logical connections to one or more remote computers, such as a remote computer 880 . The remote computer 880 may be a personal computer, a hand-held device, a server, a router, a network PC, a peer device or other common network node, and typically includes many or all of the elements described above relative to the computer 810 . The logical connections depicted in FIG. 12 include a local area network (LAN) 871 and a wide area network (WAN) 873 , but may also include other networks. Such networking environments are commonplace in offices, enterprise-wide computer networks, intranets and the Internet. When used in a LAN networking environment, the computer 810 is connected to the LAN 871 through a network interface or adapter 870 . When used in a WAN networking environment, the computer 810 typically includes a modem 872 or other means for establishing communications over the WAN 873 , such as the Internet. The modem 872 , which may be internal or external, may be connected to the system bus 821 via the user input interface 860 , or other appropriate mechanism. In a networked environment, program modules depicted relative to the computer 810 , or portions thereof, may be stored in the remote memory storage device. By way of example, and not limitation, FIG. 12 illustrates remote application programs 885 as residing on remote computer 880 . It will be appreciated that the network connections shown are exemplary and other means of establishing a communications link between the computers may be used. Although the subject matter has been described in language specific to structural features and/or methodological acts, it is to be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.
A client device accesses a shared data system and begins moving data from one location to another. The client device generates a tombstone object that indicates that includes metadata indicating that the data has been moved. When another client accesses the data at the old location, it encounters the tombstone and begins accessing the data at the new location. If the data has not already been completely moved to the new location, the second client to access the data assists in transferring the data to the new location.
7
TECHNICAL FIELD This instant specification relates to inferring the gender of a face in an image. BACKGROUND In many application domains, such as photo collection, social networking, surveillance, adult-content detection, etc, it is desirable to use an automated method to determine the gender of a person in an image. Some systems use computer vision algorithms in an attempt to determine gender by directly analyzing a face within an image to determine if the face is associated with typically male or female characteristics. SUMMARY In general, this document describes inferring the gender of a person or animal from a set of images. The faces are represented in a data structure and includes links between faces having similarities. In a first aspect, a computer-implemented method includes receiving a plurality of images having human faces. The method further includes generating a data structure having representations of the faces and associations that link the representations based on similarities in appearance between the faces. The method further includes outputting a first gender value for a first representation of a first face that indicates a gender of the first face based on one or more other gender values of one or more other representations of one or more other faces that are linked to the first representation. In a second aspect, a computer-implemented method includes receiving a plurality of images having animal faces. The method further includes generating a graph having nodes representing the faces and edges that link the nodes based on similarities in appearance between the faces represented by the nodes. The method further includes outputting a first gender value for a first node that indicates a gender of a first face associated with the first node based on one or more second gender values of one or more neighboring nodes in the graph. In a third aspect, a computer-implemented method includes receiving a plurality of images having animal faces. The method further includes generating a data structure that associates a first face with one or more second faces based on similarities in appearance between the first face and the one or more second faces. The method further includes outputting a first gender value for the first face based on one or more gender values previously associated with the one or more second faces. In a fourth aspect, a system includes a face detector for identifying faces within images. The system further includes means for generating a data structure configured to associate a first face with one or more second faces based on similarities in appearance between the first face and the one or more second faces. The system further includes an interface to output a first gender value for the first face based on one or more gender values previously associated with the one or more second faces. The systems and techniques described here may provide one or more of the following advantages. First, an automated method is provided for identifying the gender of a person (or persons) in a collection of images. Second, a gender detection method is provided that does not require large data sets for training a statistical gender classifier. Third, a method for gender detection is provided that does not rely on computer vision techniques to directly identify a gender of a face based on an image of the face. Fourth, genders associated with androgynous faces within images can be more accurately determined. The details of one or more embodiments are set forth in the accompanying drawings and the description below. Other features and advantages will be apparent from the description and drawings, and from the claims. DESCRIPTION OF DRAWINGS FIG. 1 is a schematic diagram showing an example of a system for inferring the gender of a face in an image. FIG. 2 is a block diagram showing another example of a system for inferring the gender of a face in an image. FIG. 3A shows examples of images used for inferring a gender of a face in an image. FIG. 3B shows examples of comparisons and similarities between faces in images. FIG. 3C shows an example of a weighted undirected graph of the similarities between the faces in the images. FIG. 3D shows an example of manually identified gender values for a portion of the weighted undirected graph. FIG. 4 is a flow chart showing an example of a method for constructing a weighted undirected graph of similarities between faces in images. FIG. 5 is a flow chart showing an example of a method for inferring the gender of a face in an image using a weighted undirected graph of similarities between faces in images. FIGS. 6A-D show examples of gender values in a weighted undirected graph before performing a gender inferring process and after one iteration, two iterations, and four iterations of the gender inferring process, respectively. FIG. 7A shows an example of a table that stores gender values for faces. FIG. 7B shows an example of a table that stores similarity scores between a first face and other faces. FIG. 8 shows an example of a weighted undirected graph including dummy labels. FIG. 9 is a schematic diagram showing an example of a generic computing system that can be used in connection with computer-implemented methods described in this document. Like reference symbols in the various drawings indicate like elements. DETAILED DESCRIPTION This document describes systems and techniques for inferring the gender of a face in an image. A network, such as the Internet or a wide area network, can include servers hosting images of people and/or other animals. In general, an image of a female face may have similarities with images of other female faces and an image of a male face may have similarities with images of other male faces. In certain implementations, a gender determination system analyzes the similarities between the faces, including faces having a known gender and faces having an unknown gender. The gender determination system can use the similarities and the known genders to infer a gender of one or more faces having an unknown gender. In certain implementations, a face having an unknown gender may have little or no direct similarities with the faces having a known gender. The gender determination system may determine that the face having the unknown gender has similarities with one or more other unknown gender faces. The gender determination system may also determine that one or more of the other unknown gender faces have similarities with one or more faces having known genders. The gender determination system can use the chain of intermediate faces to infer the gender of the face having an unknown gender by indirectly relating the unknown gender face to a face having a known gender. FIG. 1 is a schematic diagram showing an example of a system 100 for inferring the gender of a face in an image. The system 100 includes a gender determination system 102 and multiple publisher systems 104 a - c , such as a web logging (blogging) server, an image hosting server, and a company web server, respectively. The gender determination system 102 communicates with the publisher systems 104 a - c using one or more networks, such as the Internet, and one or more network protocols, such as Hypertext Transport Protocol (HTTP). In the case of HTTP communication, the publisher systems 104 a - c can include multiple web pages 106 a - c , respectively. For example, the web page 106 a published by the blogging system is a celebrity gossip blog, the web page 106 b published by the image hosting system is an image gallery, and the web page 106 c published by the web server system is a homepage for the ACME Corporation. The web pages 106 a - c each include one or more images 108 a - e . The images 108 a - e include faces of people and/or other animals. The gender determination system 102 retrieves the images 108 a - e from the publisher systems 104 a - c and stores the images 108 a - e in a data storage 110 . The gender determination system 102 includes an inferred gender label generator 112 that performs processing to infer the gender of the faces in the images. The inferred gender label generator 112 includes a face detector 114 and a similarity calculator 116 . The face detector 114 uses face detection algorithms known to those skilled in the art to detect faces in the images 108 a - e . In certain implementations, the face detector 114 stores the portions of the images 108 a - e that include faces in the data storage 110 . Alternatively, the face detector 114 may store information that describes the location of the face portions within the images 108 a - e . The face detector 114 passes the face information to the similarity calculator 116 or otherwise notifies the similarity calculator 116 of the face information. The similarity calculator 116 calculates similarity scores between pairs of faces. The similarity calculator 116 uses facial analysis algorithms known to those skilled in the art. For example, one such facial analysis algorithm is discussed in a paper entitled “Transformation, Ranking, and Clustering for Face Recognition Algorithm Comparison,” by Stefan Leigh, Jonathan Phillips, Patrick Grother, Alan Heckert, Andrew Ruhkin, Elaine Newton, Mariama Moody, Kimball Kniskern, Susan Heath, published in association with the Third Workshop on Automatic Identification Advanced Technologies, Tarrytown, March 2002. The inferred gender label generator 112 includes or has access to predetermined gender information for one or more of the faces. For example, a user may make an input indicating that a face in the image 108 a has a gender of female and a face in the image 108 b has a gender of male. Alternatively, the inferred gender label generator 112 may generate predetermined gender information based on an algorithm, such as associating a distinguishing feature within a face as male or female. The inferred gender label generator 112 uses the predetermined gender information and the similarity scores between the faces to link each of the faces directly or indirectly to the faces having predetermined or known genders. The inferred gender label generator 112 uses the links to infer a gender for the faces. The inferred gender label generator 112 stores the similarity scores and inferred genders in the data storage 110 as a gender label value table 118 . The gender determination system 102 can output genders of the faces as gender label information 120 a - e for the images 108 a - e , respectively, to the publisher systems 104 a - c . In another implementation, the gender determination system 102 can include, or provide gender information to, an image search engine. For example, a user may make an input indicating a search for images of people or animals having a particular gender. The gender determination system 102 , or another image search system, uses the gender label information 120 a - e to provide images having the requested gender. FIG. 2 is a block diagram showing an example of a system 200 for inferring the gender of a face in an image. The system 200 includes the gender determination system 102 as previously described. The inferred gender label generator 112 receives the images 108 a - e and may store the images 108 a - e in the data storage 110 . The inferred gender label generator 112 uses the face detector 114 to locate faces within the images 108 a - e . Subsequently or concurrently, the inferred gender label generator 112 uses the similarity calculator 116 to calculate similarity scores between faces. In the system 200 , the similarity calculator 116 is included in a graph generator 202 . The graph generator 202 generates a graph of the faces in the images 108 a - e . Each face represents a node in the graph. The graph generator 202 represents the similarity scores between faces as edges that link the nodes. Each edge is associated with its similarity score. The edges linking the nodes may be undirected, bi-directional, or uni-directional. For the purposes of clarity, the edges in the following examples are undirected unless otherwise specified. The inferred gender label generator 112 associates each face with one or more gender labels and each gender label may have a gender label value. In some implementations, the gender label values are numeric values, such as decimal numbers. For example, the face in the image 108 a may have gender labels of “Male” and “Female” with associated gender label values of “0.00” and “1.00,” respectively. The inferred gender label generator 112 stores the gender label values in the gender label value table 118 . In some implementations, the gender determination system 102 includes a data storage 204 that stores one or more predetermined gender label values 206 . The gender determination system 102 may receive the predetermined gender label values, for example, from a user input. The graph generator 202 associates the predetermined gender label values 206 with corresponding nodes in the graph. For example, a user may input the gender label values of “0.00” Male and “1.00” Female for the face in the image 108 a . The graph generator 202 associates the gender label values with the node in the graph that represents the face from the image 108 a . The inferred gender label generator 112 subsequently uses the predetermined gender label values 206 as a starting point, or seed, for the algorithm to infer other gender label values of faces included in other images. FIG. 3A shows examples of the images 108 a - e used for inferring a gender of a face in an image. The gender determination system 102 may use images such as the images 108 a - e or other images. The gender determination system 102 may also use fewer or more images than are shown here. The images 108 a - e all include a person having a face. In some implementations, an image may include multiple people or animals. In this example, the image 108 a is an adult female, the image 108 b is an adult male, the image 108 c is a female child, the image 108 d is a male child, and the image 108 e is a picture of a somewhat androgynous adult. FIG. 3B shows examples of comparisons and similarities between multiple faces 302 a - e in the images 108 a - e . The face detector 114 identifies regions within the images 108 a - e that represent the faces 302 a - e . The similarity calculator 116 compares features between faces to determine similarity scores between faces. In some implementations, the similarity calculator 116 compares pairs of faces and determines a similarity score for each pair of faces. In some implementations, the similarity score is a decimal number in the range from zero to one, where zero indicates no similarity and one indicates that the faces are identical or indistinguishable. For example, the similarity calculator 116 may determine similarity scores of “0.7” between the faces 302 b and 302 d , “0.5” between the faces 302 b and 302 e , and “0.7” between the faces 302 a and 302 c . The similarity scores of “0.7” indicate that the faces 302 b and 302 d are significantly similar and the faces 302 a and 302 c are significantly similar. The similarity score of “0.5” indicates that the faces 302 b and 302 e are only somewhat similar. The similarity calculator 116 may perform the comparison and calculate a similarity score for each pair of images. The graph generator 202 uses the similarity scores to generate the graph representing similarities between the faces 302 a - e. FIG. 3C shows an example of a weighted undirected graph 310 of the similarities between the faces 302 a - e in the images 108 a - e . The graph generator 202 represents the faces 302 a - e with multiple nodes 312 a - e , respectively. The graph generator 202 links pairs of nodes with edges that represent a similarity score between the linked pair of nodes. For example, the graph generator 202 links the nodes 312 b and 312 d with an edge having an associated similarity score of “0.7.” In some implementations, the graph generator 202 generates an edge between each pair of nodes in the weighted undirected graph 310 . In some implementations, the graph generator 202 links a portion of the pairs of nodes with edges. For example, the graph generator 202 can link pairs of nodes having a threshold similarity score. In another example, the graph generator 202 can link a threshold number of nodes to a particular node, such as the five nodes having the highest similarity scores with the particular node. For the purposes of clarity in explanation, the weighted undirected graph 310 only includes edges between neighboring nodes. FIG. 3D shows an example of manually identified gender values for a portion of the weighted undirected graph 310 . As previously described, the gender determination system 102 includes the predetermined gender label values 206 . The graph generator 202 associates the predetermined gender label values 206 with corresponding nodes. For example, the graph generator 202 associates gender label values of “1.0” Male and “0.0” Female with the node 312 b and “0.0” Male and “1.0” Female with the node 312 a. In this example of a weighted undirected graph, each node eventually has a Male gender label and a Female gender label (e.g., either predetermined or inferred). The nodes 312 a - b have predetermined Male and Female gender labels and label values. As described below, the inferred gender label generator 112 uses the weighted undirected graph 310 to infer Male and Female gender label values for the nodes 312 c - e . Although this example describes two gender labels, in other implementations, a node may have zero, three, or more gender labels as well. In some implementations, the inferred gender label generator 112 also infers gender label values for nodes having predetermined gender label values. Inferred gender label values for nodes having predetermined gender label values can be used to check the accuracy of the inferred gender label generator 112 and/or to check for possible errors in the predetermined gender label values 206 . FIG. 4 is a flow chart showing an example of a method 400 for constructing a weighted undirected graph of similarities between faces in images. In some implementations, the face detector 114 , the similarity calculator 116 , and the graph generator 202 can include instructions that are executed by a processor of the gender determination system 102 . The method 400 can start with step 402 , which identifies face regions using a face detector. For example, the inferred gender label generator 112 can use the face detector 114 to locate the regions of the images 108 b and 108 d that include the faces 302 b and 302 d , respectively. In step 404 , the method 400 compares two faces and generates a similarity score representing the similarity between the two faces. For example, the similarity calculator 116 compares the faces 302 b and 302 d and calculates the similarity score of “0.7” between the faces 302 b and 302 d. If at step 406 there are more faces to compare, then the method 400 returns to step 404 and compares another pair of faces. Otherwise, the method 400 constructs a weighted undirected graph at step 408 , where the faces are nodes and the similarity scores are edges that link the nodes. For example, the graph generator 202 constructs the nodes 312 b and 312 d representing the faces 302 b and 302 d . The graph generator 202 links the nodes 312 b and 312 d with an edge associated with the similarity score of “0.7” between the nodes 312 b and 312 d. At step 410 , the method 400 receives a user input labeling a subset of the face nodes as either male or female. For example, the gender determination system 102 may receive a user input including the predetermined gender label values 206 . The predetermined gender label values 206 indicate that the node 312 b has gender label values of “1.0” Male and “0.0” Female. The inferred gender label generator 112 uses the weighted undirected graph 310 and the predetermined gender label values 206 to infer the gender of one or more faces represented by nodes in the weighted undirected graph 310 . FIG. 5 is a flow chart showing an example of a method 500 , referred to here as an “adsorption” algorithm, for inferring the gender of a face in an image using a weighted undirected graph of similarities between faces in images. In some implementations, the inferred gender label generator 112 can include instructions that are executed by a processor of the gender determination system 102 . The adsorption algorithm 500 can be executed using information from the graphs shown in FIGS. 3C-D and can be executed for every node in the graphs. The adsorption algorithm 500 can start with step 502 , which determines if a specified number of iterations have run for a graph. If the number is not complete, step 504 is performed. In step 504 , a node representing a face is selected. For example, the inferred gender label generator 112 can select a node that has gender label values that may be modified by the algorithm, such as “Male” or “Female.” In step 506 , a gender label is selected from the selected node. For example, the inferred gender label generator 112 can select the gender label “Male” if present in the selected node. In step 508 , a gender label value for the selected gender label is initialized to zero. For example, the inferred gender label generator 112 can set the gender label value for “Male” to zero. In step 510 , a neighboring node of the selected node can be selected. For example, the selected node may specify that a neighboring node has a similarity score of “0.7” with the selected node. The inferred gender label generator 112 can select the neighboring node. In step 512 , a corresponding weighted gender label value of a selected neighbor is added to a gender label value of the selected gender label. For example, if the selected neighboring node has a gender label value for the gender label “Male,” the inferred gender label generator 112 can add this value to the selected node's gender label value for “Male.” In certain implementations, the gender label value retrieved from a neighboring node can be weighted to affect the contribution of the gender label value based on the degree of distance from the selected node (e.g., based on whether the neighboring node is linked directly to the selected node, linked by two edges to the selected node, etc.) In some implementations, the gender label value can also be based on a weight or similarity score associated with the edge. In step 514 , it is determined whether there is another neighbor node to select. For example, the inferred gender label generator 112 can determine if the selected node is linked by a single edge to any additional neighbors that have not been selected. In another example, a user may specify how many degrees out (e.g., linked by two edges, three edges, etc.) the inferred gender label generator 112 should search for neighbors. If there is another neighbor that has not been selected, steps 510 and 512 can be repeated, as indicated by step 514 . If there is not another neighbor, step 516 can be performed. In step 516 , it is determined whether there is another gender label in the selected node. For example, the selected node can have multiple gender labels, such as “Male” and “Female.” If these additional gender labels have not been selected, the inferred gender label generator 112 can select one of the previously unselected gender labels and repeat steps 506 - 514 . If all the gender labels in the node have been selected, the gender label values of the selected node can be normalized, as shown in step 518 . For example, the inferred gender label generator 112 can normalize each gender label value so that it has a value between 0 and 1, where the gender label value's magnitude is proportional to its contribution relative to all the gender label values associated with that node. In step 520 , it can be determined whether there are additional nodes in the graph to select. If there are additional nodes, the method can return to step 504 . If all the nodes in the graph have been selected, the method can return to step 502 to determine whether the specified number of iterations has been performed on the graph. If so, the adsorption algorithm 500 can end. In certain implementations, the adsorption algorithm 500 can include the following pseudo code: Set t = 0 For each node, n, in the similarity graph, G:    For each gender label, l:         Initialize the gender label: n l,t = 0.0; For t = 1..x iterations:   For each node used to label other nodes, n, in the similarity graph, G:      For each gender label, l:            Initialize the gender label value: n l,t+1 = n l,t   For each node to be labeled, n, in the similarity graph, G:         For each gender label, l:            Initialize the gender label value:            n l,t+1 = n l,injection ; //where n l,injection is a node having a static assigned value      For each node, n, in the similarity graph, G:         For each node, m, that has an edge with similarity s mn ,         to n:            For each gender label:               n l,t+1 + (s mn * m l,t )      Normalize the weight of the gender labels at each n, so that the         sum of the labels at each node = 1.0 In certain implementations, after “x” iterations, the inferred gender label generator 112 can examine one or more of the nodes of the graph and probabilistically assign a gender label to each node based on the weights of the gender labels (e.g., a label with the maximum label value can be assigned to the node). In some implementations, the number of the iterations is specified in advance. In other implementations, the algorithm terminates when the gender label values for the gender labels at each node reach a steady state (e.g., a state where the difference in the label value change between iterations is smaller than a specified epsilon). In another alternative method, gender label values for nodes can be inferred by executing a random walk algorithm on the graphs. More specifically, in some implementations, given a graph, G, the inferred gender label generator 112 can calculate gender label values, or label weights, for every node by starting a random walk from each node. The random walk algorithm can include reversing the direction of each edge in the graph if the edge is directed. If the edge is bi-directional or undirected, the edge can be left unchanged. The inferred gender label generator 112 can select a node of interest and start a random walk from that node to linked nodes. At each node where there are multiple-out nodes (e.g., nodes with links to multiple other nodes), the inferred gender label generator 112 can randomly select an edge to follow. If the edges are weighted, the inferred gender label generator 112 can select an edge based on the edge's weight (e.g., the greatest weighted edge can be selected first). If during the random walk, a node is selected that is a labeling node (e.g., used as a label for other nodes), the classification for this walk is the label associated with the labeling node. The inferred gender label generator 112 can maintain a tally of the labels associated with each classification. If during the random walk, a node is selected that is not a labeling node, the inferred gender label generator 112 selects the next random path, or edge, to follow. The inferred gender label generator 112 can repeat the random walk multiple times (e.g., 1000s to 100,000s of times) for each node of interest. After completion, the inferred gender label generator 112 can derive the gender label values based on the tally of labels. This process can be repeated for each node of interest. Additionally, in some implementations, the inferred gender label generator 112 generates a second data structure, such as a second graph. The second graph can include nodes substantially similar to the weighted undirected graph 310 . In one example, the weighted undirected graph 310 includes Male gender label values and a second graph includes Female gender label values. In some implementations, the adsorption algorithm 500 can also be performed on the second graph. The inferred gender label generator 112 can select and compare the resulting label value magnitudes for a corresponding node from both the first and second graphs. In some implementations, the inferred gender label generator 112 can combine the gender label value magnitudes from each graph through linear weighting to determine a final gender label value magnitude (e.g., the first graph's gender label value contributes 0.7 and the second graph's gender label value contributes 0.3). In other implementations, the gender label values can be weighed equally to determine the final gender label value (e.g., 0.5, 0.5), or the inferred gender label generator 112 can give one gender label value its full contribution while ignoring the gender label value from the other graph (e.g., [1.0, 0.0] or [0.0, 1.0]). In other implementations, the inferred gender label generator 112 can use a cross-validation method to set the contribution weights for gender label value magnitudes from each graph. For example, the inferred gender label generator 112 can access nodes in a graph, where the nodes have gender label value magnitudes that are known. The inferred gender label generator 112 can compare the actual gender label value magnitudes with the known gender label value magnitudes. The inferred gender label generator 112 can then weight each graph based on how closely its gender label values match the known gender label values. In certain implementations, the inferred gender label generator 112 can compare the gender label value magnitudes to an expected a priori distribution, instead of or in addition to examining the final gender label magnitudes. For example, if a summed value of a first gender label across all nodes is 8.0 and the summed value of a second gender label across all of the nodes is 4.0, the a priori distribution suggests that first gender label may be twice as likely to occur as the second gender label. The inferred gender label generator 112 can use this expectation to calibrate the gender label value magnitudes for each node. If in a particular node, the first gender label value is 1.5 and the second gender label value is 1.0, then the evidence for the first gender label, although higher than the second gender label, is not as high as expected because the ratio is not as high as the a priori distribution. This decreases the confidence that the difference in magnitudes is meaningful. A confidence factor can be translated back into the rankings. In some implementations, if the difference in magnitudes is below a confidence threshold, the inferred gender label generator 112 can rank a gender label with a lower value above a gender label with a higher value (e.g., manipulate the lower value so that it is increased to a gender label value greater than the higher value). For example, if the first gender label's value is expected to be three times the value of the second gender label, but was only 1.1 times greater than the second gender label, the inferred gender label generator 112 can rank the second gender label above the first gender label. In some implementations, the confidence factor can be kept as a confidence measure, which can be used, for example, by machine learning algorithms to weight the resultant label value magnitudes. In yet other implementations, instead of or in addition to comparing the gender label value magnitudes based on the a priori distribution of the nodes, the inferred gender label generator 112 can compare the gender label value magnitudes based on an end distribution of magnitudes across all nodes. For example, the inferred gender label generator 112 can measure how different a particular node's distribution is from an average calculated across all nodes in a graph. FIGS. 6A-D show examples of gender values in a weighted undirected graph 600 before performing a gender inferring process and after one iteration, two iterations, and four iterations of the gender inferring process, respectively. Referring to FIG. 6A , the weighted undirected graph 600 includes predetermined and initial gender values for the nodes 312 a - e . The weighted undirected graph 600 only shows Male gender labels for the sake of clarity. Other gender labels may be included in the weighted undirected graph 600 or another graph having nodes corresponding to nodes in the weighted undirected graph 600 . The weighted undirected graph 600 includes predetermined gender label values for the nodes 312 a - b of “0.00” Male and “1.00” Male, respectively. The nodes 312 c - e have initial gender label values of “0.50” Male. In some implementations, an initial gender label value may be a predetermined value, such as “0.50.” Alternatively, the initial gender label value may be based on the average of the predetermined gender label values 206 or another set of gender label values. Referring to FIG. 6B , the weighted undirected graph 600 now shows the Male gender label values of the nodes 312 a - e after one iteration of the inferred gender label generator 112 . In this example, the Male gender label values of the nodes 312 a - b are fixed at “0.00” and “1.00,” respectively. The Male gender label values of the nodes 312 c - e are now “0.25,” “0.73,” and “0.53,” respectively. The relatively high similarity between the nodes 312 a and 312 c as compared to other nodes gives the node 312 c a Male gender label value (“0.25”) close to the Male gender label value of the node 312 a (“0.00”). Similarly, the relatively high similarity between the nodes 312 b and 312 d as compared to other nodes gives the node 312 d a Male gender label value (“0.73”) close to the Male gender label value of the node 312 b (“1.00”). The node 312 e has slightly higher similarity with the nodes 312 b and 312 d leading to a Male gender value (“0.53”) that leans toward Male. Referring to FIG. 6C , the weighted undirected graph 600 now shows the gender label values for the nodes 312 a - e after two iterations of the inferred gender label generator 112 . The Male gender label value of the node 312 c has increased by “0.01” to “0.26.” The Male gender label value of the node 312 d has increased by “0.01” to “0.74.” The Male gender label value of the node 312 e has increased by “0.01” to “0.54.” In some implementations, the inferred gender label generator 112 may stop processing a graph after the change in each gender label value is below a particular threshold, such as “0.01.” Referring to FIG. 6D , the weighted undirected graph 600 now shows the gender label values for the nodes 312 a - e after four iterations of the inferred gender label generator 112 . The Male gender label value of the node 312 d has increased by “0.01” to “0.75.” The Male gender label values of the nodes 312 a - e have now converged within “0.01.” The inferred gender label generator 112 stops processing the weighted undirected graph 600 and outputs the Male gender label values. Alternatively, the inferred gender label generator 112 may stop processing after a predetermined number of iterations, such as five iterations. In some implementations, the inferred gender label generator 112 infers Female gender label values for the nodes 312 a - e in addition to the Male gender label values previously described. The inferred gender label generator 112 can compare and/or combine the Male and Female gender label values to determine a gender for the faces 302 a - e associated with the nodes 312 a - e . For example, if the Male gender label value of a node is larger than its Female gender label value than the corresponding face is determined to be Male and vice versa for Female. FIG. 7A shows an example of a table 700 that stores gender values for the faces 302 a - e . The weighted undirected graphs 310 and 600 may stored in the data storage 110 or structured in a memory module as tables, such as the table 700 . In particular, the table 700 includes an identifier 702 for each of the faces 302 a - e , an indication 704 of where similarity scores to other faces can be found, a Male gender label value 706 , and a Female gender label value 708 . The entry in the table 700 for Face A indicates that the similarity scores associated with face can be found in Table A. FIG. 7B shows an example of a table 710 that stores similarity scores between a first face and other faces. In particular, the table 710 represents Table A, which includes the similarity scores associated with Face A from the table 700 . The table 710 includes an identifier 712 for each of the associated faces and a corresponding similarity score 714 . FIG. 8 shows an example of a weighted undirected graph 800 including dummy labels. In certain implementations, dummy labels can be used in the weighted undirected graph 800 to reduce effects of distant neighboring nodes. When the label value of a node is determined based on, for example, the label with the greatest label value, the weight assigned to the dummy label can be ignored and the remaining weights used in the determination. For example, the dummy labels' contribution can be removed from the calculation of the label values at the end of the algorithm (e.g., after the label values have reached a steady state or a specified number of iterations have occurred). In certain implementations, dummy labels can be used in all of the graphs generated by the inferred label generator. In other implementations, a user may specify for which graph(s) the dummy labels may be used. The example of dummy labels shown here associates a dummy node with each of the nodes 312 a - e in the weighted undirected graph 800 . In other implementations, dummy labels are assigned to a small number of nodes, such as nodes that are not associated with initial gender label values. FIG. 9 is a schematic diagram of a generic computing system 900 . The generic computing system 900 can be used for the operations described in association with any of the computer-implement methods described previously, according to one implementation. The generic computing system 900 includes a processor 902 , a memory 904 , a storage device 906 , and an input/output device 908 . Each of the processor 902 , the memory 904 , the storage device 906 , and the input/output device 908 are interconnected using a system bus 910 . The processor 902 is capable of processing instructions for execution within the generic computing system 900 . In one implementation, the processor 902 is a single-threaded processor. In another implementation, the processor 902 is a multi-threaded processor. The processor 902 is capable of processing instructions stored in the memory 904 or on the storage device 906 to display graphical information for a user interface on the input/output device 908 . The memory 904 stores information within the generic computing system 900 . In one implementation, the memory 904 is a computer-readable medium. In one implementation, the memory 904 is a volatile memory unit. In another implementation, the memory 904 is a non-volatile memory unit. The storage device 906 is capable of providing mass storage for the generic computing system 900 . In one implementation, the storage device 906 is a computer-readable medium. In various different implementations, the storage device 906 may be a floppy disk device, a hard disk device, an optical disk device, or a tape device. The input/output device 908 provides input/output operations for the generic computing system 900 . In one implementation, the input/output device 908 includes a keyboard and/or pointing device. In another implementation, the input/output device 908 includes a display unit for displaying graphical user interfaces. The features described can be implemented in digital electronic circuitry, or in computer hardware, firmware, software, or in combinations of them. The apparatus can be implemented in a computer program product tangibly embodied in an information carrier, e.g., in a machine-readable storage device or in a propagated signal, for execution by a programmable processor; and method steps can be performed by a programmable processor executing a program of instructions to perform functions of the described implementations by operating on input data and generating output. The described features can be implemented advantageously in one or more computer programs that are executable on a programmable system including at least one programmable processor coupled to receive data and instructions from, and to transmit data and instructions to, a data storage system, at least one input device, and at least one output device. A computer program is a set of instructions that can be used, directly or indirectly, in a computer to perform a certain activity or bring about a certain result. A computer program can be written in any form of programming language, including compiled or interpreted languages, and it can be deployed in any form, including as a stand-alone program or as a module, component, subroutine, or other unit suitable for use in a computing environment. Suitable processors for the execution of a program of instructions include, by way of example, both general and special purpose microprocessors, and the sole processor or one of multiple processors of any kind of computer. Generally, a processor will receive instructions and data from a read-only memory or a random access memory or both. The essential elements of a computer are a processor for executing instructions and one or more memories for storing instructions and data. Generally, a computer will also include, or be operatively coupled to communicate with, one or more mass storage devices for storing data files; such devices include magnetic disks, such as internal hard disks and removable disks; magneto-optical disks; and optical disks. Storage devices suitable for tangibly embodying computer program instructions and data include all forms of non-volatile memory, including by way of example semiconductor memory devices, such as EPROM, EEPROM, and flash memory devices; magnetic disks such as internal hard disks and removable disks; magneto-optical disks; and CD-ROM and DVD-ROM disks. The processor and the memory can be supplemented by, or incorporated in, ASICs (application-specific integrated circuits). To provide for interaction with a user, the features can be implemented on a computer having a display device such as a CRT (cathode ray tube) or LCD (liquid crystal display) monitor for displaying information to the user and a keyboard and a pointing device such as a mouse or a trackball by which the user can provide input to the computer. The features can be implemented in a computer system that includes a back-end component, such as a data server, or that includes a middleware component, such as an application server or an Internet server, or that includes a front-end component, such as a client computer having a graphical user interface or an Internet browser, or any combination of them. The components of the system can be connected by any form or medium of digital data communication such as a communication network. Examples of communication networks include, e.g., a LAN, a WAN, and the computers and networks forming the Internet. The computer system can include clients and servers. A client and server are generally remote from each other and typically interact through a network, such as the described one. The relationship of client and server arises by virtue of computer programs running on the respective computers and having a client-server relationship to each other Although a few implementations have been described in detail above, other modifications are possible. For example, image or facial labels other than gender may be used, such as ethnicity or complexion. In addition, the logic flows depicted in the figures do not require the particular order shown, or sequential order, to achieve desirable results. In addition, other steps may be provided, or steps may be eliminated, from the described flows, and other components may be added to, or removed from, the described systems. Accordingly, other implementations are within the scope of the following claims.
The subject matter of this specification can be embodied in, among other things, a computer-implemented method that includes receiving a plurality of images having human faces. The method further includes generating a data structure having representations of the faces and associations that link the representations based on similarities in appearance between the faces. The method further includes outputting a first gender value for a first representation of a first face that indicates a gender of the first face based on one or more other gender values of one or more other representations of one or more other faces that are linked to the first representation.
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BACKGROUND OF THE INVENTION The present invention is directed to cutting or slicing devices for use primarily in the culinary arts. Devices and machines for cutting or slicing fruits and vegetables are old in the art and in fact certain well known hand-operated devices have been developed for cutting or slicing only tomatoes. In certain instances such devices usually have the cutting blades mounted in a vertical plane upon a suitable supporting base or platform. An article engaging or pusher device is usually mounted on or in said base or platform for sliding movement with respect thereto contemporaneous with engaging the article to be cut or severed. In lieu of slidably mounting the pusher element upon the supporting base said pusher element may be pivotally mounted upon the base whereby the pusher element will, either swing or move through the fixed cutting blades. In certain prior art devices such as MORRETT, U.S. Pat. No. 3,605,840, dated Sept. 20, 1971, reference is made to rotating the article supported on the cutting knives or blades by the pusher element just prior to forcing the article through the fixed cutting knives. In the prior art patent to GIANGIULIO, U.S. Pat. No. 3,365,582, dated Feb. 20, 1968, the article to be cut, namely, a tomato is pushed through the fixed cutting knives without any attempt being made to rotate the tomato. In fact GIANGIULIO seems to be more concerned in moving the tomato into and through the fixed cutting knives without any rotation of the tomato. In GERSON, U.S. Pat. No. 3,605,839, dated Sept. 20, 1971, the pusher or article engaging member is pivotally mounted on one side of the fixed cutting blades and arranged to extend through said blades for moving an article into engagement with the blades on the side opposite from the pivot point of the pusher. In the various instances enumerated the article has been pushed through the fixed cutting blades utilizing article engaging or pushing members of varying types. The consensus regarding the mode of operation seems to be that articles, such as tomatoes with their relatively thick skins, should be pushed through the fixed cutting blades with a slight amount of rotation of the article, in certain instances, to enhance the slicing operation. SUMMARY OF THE INVENTION The present invention is directed to a slicing device that is readily capable of slicing tomatoes and which includes a frame for supporting a plurality of fixed cutting blades. A plurality of link elements are pivotally connected to said frame with an article engaging or pusher member pivotally connected to said link elements. The frame and article engaging or pusher member when connected to one another by the link elements tend to define a parallelogram in that the pivot points are maintained at a fixed distance from one another. The manner of connecting the pusher member to the link elements causes a certain segment or surface of said pusher member to move in a path wherein said segment or surface is disposed in a series of horizontal planes that are parallel to the horizontal plane of the cutting blades. Thus said segment or surface engages the surface of the tomato being sliced only during the final stages of the slicing operation. BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a perspective view of the slicing device embodying the present invention; FIG. 2 is a vertical sectional view of the slicing device of the present invention; FIG. 3 is a perspective view of the cutting blades and holder; FIG. 4A is a side elevational view of a portion of the slicing device of the present invention showing one position of the article on the cutting blades and the pusher member engaging said article; FIG. 4B is a view similar to FIG. 4A but showing the article in its initial stages of being sliced; and FIG. 4C is still another view similar to FIG. 4A but showing the article after it has been moved through the cutting blades. DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawing there is shown in FIG. 1 a tubular frame member consisting of elongated side pieces 10 terminating in downwardly extending leg elements and which side pieces are connected by transverse end members 12. The tubular frame members has supported thereon a base or platform member 14 which is formed with a centrally disposed rectangularly shaped opening 16 for receiving a plurality of fixed cutting blades or elements 18. The cutting blades 18, FIG. 3, are arranged in spaced parallel relation with respect to one another and the respective ends of each blade are positioned in slots 20 formed in the innermost faces of header members 22. The header members 22 are formed with longitudinally extending bores 24 which intersect the slots 20 for the reception of retaining rods 26. Each of the cutting blades 18 is formed with a suitable aperture at each end so that said blades may be anchored in the headers 22 by means of the rods 26 extending through the bores 24 in the headers and also passing through the openings in the ends of the cutting blades 18. The header members 22 with the cutting blades 18 assembled therein are positioned within the rectangular opening 16 in the base or platform member 14. The header members are anchored or secured in said base or platform member by fastening elements 28 that extend through apertures in the ends of the base or platform member 14 and project into suitable recessed bores, not shown, provided in the ends of the headers 22. Thus upon adjustment of the fastening elements 28 adequate longitudinal tension may be maintained on the various cutting blades 18 as same are retained in the headers 22. While only one pair of fastening elements 28 is shown in FIG. 1, it is to be understood that the other end of the base or platform member 14 is also provided with similar types of fastening elements which engage recessed bores provided in the end of the other header member 22. Thus the longitudinal tension that may be maintained on the cutting blades 18 may be provided by adjusting the fastening elements 28 at one or both ends of the base or platform 14. The base or platform member 14, FIG. 1, has pivotally mounted thereon, adjacent one end of the opening 16, a pair of link members or elements 30, only one of which is shown in FIG. 1. A second pair of link elements or members 32, only one of which is shown in FIG. 1, are pivotally connected to the base or platform member 14 adjacent one end of the rectangular opening 16. The free ends of the link elements or members 30 and 32 are pivotally connected to an article engaging or pusher element 34. The pusher element 34 is formed with a substantially rectangular solid upper portion 36 whose width is substantially the same as the width of the header members 22. The portion 36 of the pusher element 34 is the part to which the upper ends of the links 30 and 32 are pivotally connected by suitable fastening elements and in addition a handle 38 is connected to said upper portion 36. The lower face of the portion 36 of the pusher element 34 is provided with a plurality of integrally formed impeller or pusher blades 40 that are arranged in spaced parallel relation with respect to one another and are adapted to enter the spaces that are defined by the cutting blades 18 carried in the headers 22 when said cutter blades and headers are positioned in the base or platform member 14 in the manner as illustrated in FIG. 1. The impeller or pusher blades 40, depending from the upper portion 36 of the pusher element 34, are at the forward end of the pusher element of uniform depth so as to define or provide a relatively flat surface or area 42, FIGS. 4A and 4B. The impeller or pusher blades 40 from the flat surface or area 42 merged into an arcuate segmental portion 44 which terminates in a downwardly inclined rear segment or portion 46 which inclined rear segment or portion is disposed at an angle of approximately 60° to the horizontal. The rearmost edge or face of each impeller blade 40 terminates in a vertical surface 48, FIGS. 1 and 4, so that the rearmost edge or surface of each of the impeller or pusher blades 40 terminates in the same vertical plane which is disposed at right angles to the topmost surface of the upper portion 36 of the pusher element 34. The link element 32 is formed as a single U-shaped member that is pivotally connected to the base or platform member 14 so that a segmental portion of said link element projects below the base or platform member 14 in the manner as shown in FIGS. 1 and 2. This lower segmental portion of the link element 32 acts as a stop member by engaging the under surface of the base or platform 14 upon the pivotal movement of the article engaging or pusher element 34 and thus maintains the upper portion 36 of the pusher element 34 in spaced relation to the cutting blades 18 when the pusher element 34 has reached the end of its travel or approaches the position as shown in FIG. 4C. A pair of positioning members 52 are affixed to certain of the cutting blades 18, FIGS. 3 and 4A, adjacent one of the headers 22 for initially positioning the article that is to be sliced upon the cutting blades. In the use of the slicing device of the present invention, the cutting blades 18, with the positioning members 52 mounted on certain of the blades, are secured to the headers 22 by means of the retaining rods 26. The headers are then positioned within the rectangular opening 16 of the base or platform member 14 where they are retained by the fastening elements 28 which also apply necessary tension to the cutting knives in the securing of the headers to the base or platform 14. The article engaging or pusher element 34 is pivotally mounted on the base or platform member 14, and, as illustrated in FIG. 1, said pusher element, in its inoperative position, tends to overlie the header member 22 and the portion of the base or platform member 14 at the left hand end of said base or platform when viewing FIG. 1. By so positioning the pusher element 34 over the base or platform member 14 and the header 22 practically the entire area of the cutting knives is free of any obstruction and readily permits the placing of the article that is to be sliced upon the positioning members 52. Assuming that the article so positioned on the members 52 is a tomato the handle 38 is then grasped by the operator and moved from the left to the right, when viewing FIG. 1, so that the pusher member 34 is moved upwardly and forwardly due to the fixed link members 30 and 32 being pivotally connected to the base or platform member 14. As the pusher element 34 moves upwardly and forwardly the flat surface 42 of the impeller or pusher blades 40 initially overlies the top surface of the article that is to be sliced and this is the position that is substantially illustrated in FIG. 4A. The continued movement of the pusher element 34 through the handle 38 causes the pusher element to be elevated to a still higher point as the links 30 and 32 move about their pivot point with the base or platform member 14 so that when the links 30 and 32 are in a vertical position with respect to the base or platform 14, the pusher element 34 is at the highest point of its travel. As the pusher element is being elevated by the pivotal movement of the links 30 and 32, the arcuate segmental portion 44 of the impeller or pusher blades 40 will engage the article supported on the positioning members 52 of the cutting blades 18 and impart a rotative movement to said article while at the same time applying pressure to the article so as to force same into engagement with the cutting edge of the blades 18. The continued movement of the pusher member 34 will continue to apply pressure to the article that is to be sliced so that the arcuate segmental portion 44 of the pusher element 34 will tend to cup the article being sliced and to force same against the cutting knives 18 in a somewhat downwardly direction so that the pressure on said article is in an angular direction with respect to the horizontal surface of the cutting blades 18. The continued movement of the pusher element 34 will cause the links 30 and 32 to move from their most vertically extended position to an inclined position towards the right hand end of the base or platform 14, when viewing FIG. 1, so that the inclined rear segmental portion 46 of the impeller blades 40 will then be assisting the arcuate segmental portion 44 of said blades in engaging the article to be sliced and in forcing said article against the cutting knives 18. This position of the pusher element 40 is more or less illustrated in FIG. 4B. At this particular point the cutting knives have penetrated the article to be sliced and the continued movement of the pusher element 34 through the link elements 30 and 32 causes the impeller blades 40 to force the article through the cutting knives 18 until such time as the solid upper portion 36 of the pusher element 40 is disposed in close proximity to the upper surface of the cutting blades 18. The portion 36 of the pusher element 34 is maintained in spaced relation to the upper surface of the cutting blades 18 by the segmental portion 50 of the link 32 moving about the pivotal connection of said link with the base or frame member 14 in such a manner that the segmental portion 50 strikes the lower surface of the base or platform 14 and thus acts as a limit stop for the movement of the pusher element 34. It is to be noted that the pusher element 34 in conjunction with the base or platform 14 and the link elements 30 and 32 tend to define a parallelogram and in view of this arrangement the upper portion 36 of the pusher element 34 is always maintained in a horizontal plane that is parallel to the horizontal plane of the cutting knives 18 and base or platform 14. This movement of the pusher element 34 through the links 30 and 32 and its relationship with the base or platform 14 is clearly illustrated in FIGS. 4A, 4B and 4C. The positioning of the article, such as a tomato, upon the members 52 tends to prevent said article from sliding along the upper surface of the cutting blades 18 when said article is engaged by the pusher element 34. Thus as the pusher element is moved through its path of travel by the link elements 30 and 32 the various surfaces or areas of the impeller or pusher blades 40 will engage said article to initially impart a rotating motion to said article contemporaneous with the application of pressure thereto which will result in a penetration through the rind or tough outer skin of the article by the cutting edges of the blades 18 resulting in the severing of the article into a plurality of slices as said article passes through the spaces between the adjacent cutting blades. Although the foregoing description is necessarily of a detailed character, in order that the invention may be completely set forth, it is to be understood that the specific terminology is not intended to be restrictive or confining, and that various rearrangements of parts and modifications of detail may be resorted to without departing from the scope or spirit of the invention as herein claimed.
An apparatus for slicing fruit and vegetables such as potatoes, carrots and onions as well as tomatoes and hard boiled eggs and the like. A set of parallel cutting blades are positioned in a horizontal plane within a frame member for initially receiving the article to be cut while an article engaging member or pusher is pivotally connected to said frame for engaging and forcing said article through said cutting blades.
8
CROSS-REFERENCE TO RELATED APPLICATIONS [0001] Not Applicable STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH [0002] Not Applicable FIELD OF THE INVENTION [0003] The present invention relates to endoscopes, and in particular those in which the rotational orientation of the endoscopic image as viewed on a screen is presented in its actual relationship to the viewer's reference frame. BACKGROUND OF THE INVENTION [0004] An endoscope is an elongated tubular structure which is inserted into body cavities to examine them. The endoscope includes a telescope with an objective lens at its distal end. The telescope usually includes an image-forwarding system. In rigid endoscopes it is a series of spaced-apart lenses. In flexible endoscopes it is a bundle of tiny optical fibers assembled coherently to forward the image. Some endoscopes include a camera means, such as a CCD or CMOS image sensor, in the distal portion and forward the image electronically. This invention is applicable to all types of image forwarding systems. [0005] Many endoscopes view only directly forward. Others feature fixed or movable reflectors in the distal portion to allow off-axis viewing. Some, most commonly flexible types, feature actuated bending portions at the distal end. This invention is applicable to all types of axial, non-axial, and variable direction of view endoscopes. [0006] At the proximal end of the image-forwarding system, some endoscopes include an ocular lens which creates a virtual image for direct human visualization. Often a camera means, such as a CCD or CMOS chip, is connected to the endoscope. It receives the image and produces a signal for a video display. Some endoscopes have a camera means built directly into the endoscope. [0007] While surgeons can, and often do, look directly into the endoscope through an ocular lens, it has become more common for them to use an attached video camera and observe an image on a video screen. In a surgical or diagnostic procedure, the surgeon manipulates the endoscope. He may cause it to pitch about a lateral axis or roll about a longitudinal axis. As these manipulations occur to an endoscope with an attached camera, the camera faithfully relates what it sees, with its own upright axis displayed as the upright axis of the image on the display. This often results in rotation of the viewed image. [0008] That is the very problem. When the image is displayed on the screen and the endoscope is manipulated, it is as though the surgeon must tilt his head to follow the rotating image. However, the surgeon is standing up, and the rotating image is distracting to him. What he really wants to see on the screen is an image that is oriented the same as he would see it if he were inside, standing up, with the same upright orientation. [0009] A solution to this problem is proposed in U.S. Pat. No. 5,307,804 to Bonnet (1994), which is incorporated herein by reference in its entirety. An object of this invention was to maintain the orientation of an endoscopic image without the use of electronic sensing and positioning devices. A pendulum fixed to a camera is rotatably attached to an endoscope. The pendulum maintains an orientation with respect to gravity around the endoscope longitudinal axis. As the endoscope rotates, the pendulum causes the camera to rotate in the opposite direction relative to the endoscope. This is intended to maintain the image in a proper orientation. [0010] An endoscope with rotational orientation correction is also suggested in U.S. Pat. No. 5,899,851 to Koninckx (1999), which is incorporated herein by reference in its entirety. An electronic rotation pick-up means responsive to gravity senses rotation of a camera around the endoscope longitudinal axis. An image rotator rotates the camera image according to the rotation signal from the rotation pick-up means. [0011] Another endoscope and camera system with rotational orientation correction is disclosed in U.S. Pat. No. 6,097,423 to Mattsson-Boze, et al. (2000), which is incorporated herein by reference in its entirety. Electronic sensing and positioning devices combine to sense and correct the rotation of a camera rotatably attached to an endoscope. An accelerometer fixed to the camera serves as an electronic rotation pick-up means responsive to gravity. A motor rotates the camera according to signals from the accelerometer. This accelerometer and motor system is functionally equivalent to the pendulum described by Bonnet. While the pendulum relies on the force of gravity to rotate, the small accelerometer sensitively measures gravity and the motor rotates the assembly accordingly. The system can therefore be thought of as an electro mechanical pendulum. Mattsson-Boze also recognizes rotation of the image by electronic manipulation to correct the image orientation, but actively discourages this practice for several reasons. [0012] U.S. Pat. No. 6,471,637 to Green, et al. (2002), which is incorporated herein by reference in its entirety, discloses the same apparatus as disclosed in Mattsson-Boze, and suggests two alternative methods for image rotation. In the first method, an optical image rotator is used instead of a rotating camera. In the second method, electronic manipulation is used to correct the image orientation. Also, one or more gyroscopes are suggested as alternative electronic rotation pick-up means. [0013] U.S. patent application Ser. No. 10/093,650 by Chatenever, et al. (2002), which is incorporated herein by reference in its entirety, discloses the same apparatus as disclosed in Mattsson-Boze and in Green, and suggests two alternative methods for electronic rotation pick-up. In the first method, image analysis is used to compute a rotational signal. In the second method, a machine vision system is used to compute a rotation signal. [0014] All of the above solutions compensate only for roll about the longitudinal axis, and provide a rotationally corrected image for axial viewing endoscopes. They also provide an approximation of the correct orientation for slightly oblique viewing endoscopes held near horizontal. None of the above disclosures suggest a solution that works for significantly oblique, side, or retro viewing endoscopes. [0015] Oblique, side, or retro viewing endoscopes require a solution that takes into account the off-axis viewing direction and the endoscope pitch. Variable direction-of-view endoscopes further complicate the situation. [0016] It is an object of this invention to maintain the proper upright orientation (with respect to the viewer) of a viewed image from an endoscope. It is an additional object of this invention to be applicable to any axial, oblique, side, or retro viewing endoscope as well as any endoscope with a variable direction of view. BRIEF SUMMARY OF THE INVENTION [0017] According to a feature of this invention an electronic rotation pick-up means is fixed to the housing of an endoscope. The electronic rotation pick-up means produces signals indicating rotations of the endoscope. A microprocessor uses these signals to calculate a necessary amount of rotational correction for the endoscopic view orientation. The calculation includes factors to account for endoscope roll, endoscope pitch, and endoscope viewing direction. An image rotator rotates the endoscopic image by the calculated correction amount. The rotated image is displayed on a video display device. With this arrangement the view presented by the video display will always be “upright”, as though viewed by a surgeon standing or sitting in an upright position. [0018] What is claimed is a method for maintaining the proper upright orientation (with respect to the viewer) of an image from an endoscope comprising calculating an image orientation correction, wherein said calculating comprises accounting for the effects on image orientation caused by endoscope pitch, endoscope roll, and endoscope direction of view; rotating said image by said orientation correction; and presenting said image as corrected by said rotating. BRIEF DESCRIPTION OF THE DRAWINGS [0019] FIG. 1 is a schematic view of an endoscope useful with this invention; [0020] FIG. 2 illustrates endoscope attitude; and [0021] FIG. 3 shows the image orientation correction in accordance with the invention. DETAILED DESCRIPTION OF THE INVENTION [0022] FIG. 1 schematically shows an endoscope. The endoscope includes a shaft 10 that contains elements that are conventionally provided. The shaft has a longitudinal axis 12 . [0023] An objective optical system is provided at the distal end of the shaft to give the endoscope a view vector 14 and a field of view 16 . The objective optical system comprises components such as lenses, prisms, reflectors, etc. The objective optical system may be adjustable or mounted adjustably to provide a variable direction of view. [0024] A housing 18 is provided at the proximal end of the shaft 10 . An image sensing device or camera 20 is mounted in the housing 18 . It is configured to receive images 22 from the objective optical system. The housing 18 encases an electronic microprocessor (not shown) for performing calculations. The microprocessor is in communication with an image rotator (not shown), also contained within the housing. [0025] Image rotation can be accomplished in one or more of three ways: physical rotation of the image sensor; optical rotation of the received image prior to incidence upon the image sensor; and electronic rotation of the image within a processor. The details of these methods are not necessary for an understanding of this invention, but are described in Chatenever and other prior art. [0026] Electronic rotation pick-up means, in the preferred embodiment three accelerometers 24 , 26 , 28 responsive to gravity, are mounted to the housing 18 . Each accelerometer measures a component of gravity along a particular measurement axis. The accelerometers provide pulse-width-modulated signals to the processor which can convert each signal into a gravitational force measurement. Changes in the gravitational force measurements from the accelerometers are related to rotations of the endoscope. [0027] In order to adequately describe the method of the current invention, an appropriate mathematical framework needs to be defined. [0028] The housing 18 has a longitudinal axis 30 and a lateral axis 32 which are horizontal when the housing is in its upright position, and an upright axis 34 which is vertical when the housing is in its upright position. These axes 30 , 32 , 34 are orthogonal. Each accelerometer axis is aligned with an axis of the housing 18 . The first accelerometer 24 measures a component of gravity along the longitudinal axis 30 . The second accelerometer 26 measures a component of gravity along the lateral axis 32 . The third accelerometer 28 measures a component of gravity along the upright axis 34 . The force from the longitudinal accelerometer 24 is Z. The force from the lateral accelerometer 26 is X. The force from the upright accelerometer 28 is Y. [0029] The endoscope has a view vector 14 . The camera upright projection 36 is the projection of the default upright axis 38 of the camera 20 through the optics and along the view vector 14 . [0030] A view vector pivot axis 40 is defined at the distal end of the endoscope, initially aligned with the housing upright axis 34 . The pivot axis 40 may or may not exist in the actual implementation of the endoscope, but is defined as part of the mathematical framework. The pivot axis 40 may be realigned by rotating it about the longitudinal axis 12 . The variable theta is used to describe the angle of the pivot axis 40 relative to the upright axis 34 as rotated about the longitudinal axis 12 . The variable phi is used to describe the angle of the view vector 14 relative to the longitudinal axis 12 as rotated about the pivot axis 40 . The variable zeta is used to describe the angle of the camera upright projection 36 relative to the pivot axis 40 as rotated about the view vector 14 . It should be noted that the above parameterization uses ZYZ Euler angles, which are commonly used to describe three dimensional rotations. [0031] For simple oblique, side, or retro viewing endoscopes, the above parameterization variables theta, phi, and zeta will be fixed constants defined for each endoscope. Variable direction of view endoscopes require that one or more of the variables change during operation to reflect the changing direction of view. [0032] During use, the endoscope will be positioned with an attitude as shown in FIG. 2 . The attitude is parameterized as pitch and roll. The variable alpha is used to describe the pitch angle of the longitudinal axis 12 relative to horizontal 42 . The variable beta is used to describe the roll angle of the endoscope about its longitudinal axis 12 . Both pitch and roll may be adjusted during use. [0033] The microprocessor calculates pitch and roll from the accelerometer outputs according to the formulas: β = arctan ⁢ X Y α = arctan ⁢ Z Y / cos ⁢   ⁢ β [0034] As shown if FIG. 3 , the camera upright projection 36 is offset from gravity upright 48 by a correction angle. The variable gamma is used to describe the correction angle as a rotation about the view vector 14 . The microprocessor calculates gamma according to the formula: γ = - ζ - arctan ⁢ - sin ⁢   ⁢ α ⁢   ⁢ sin ⁢   ⁢ ϕ + cos ⁢   ⁢ α ⁢   ⁢ cos ⁢   ⁢ ϕ ⁢   ⁢ sin ⁡ ( β + θ ) cos ⁢   ⁢ α ⁢   ⁢ cos ⁡ ( β + θ ) [0035] The image rotator rotates the image by the angle gamma to align the image in the gravity upright orientation. A video display (not shown) is used to provide the corrected image to the user. The video display may be any device suitable for displaying images from the endoscope. [0036] In an alternative embodiment, one or more gyroscopes can be used as the electronic rotation pick-up means. The gyroscope output is used to determine the attitude of the endoscope. A gyroscope creates a signal representative of a force proportional to the angular displacement relative to its axis of rotation. Methods of determining attitude using gyroscopes are described in Chatenever, but the details of these methods are not necessary for an understanding of this invention. [0037] In a further embodiment of the present invention, a machine vision system is used to compute the attitude of the endoscope. In such a system, the endoscope has thereon or therein at least one signal emitting element which emits some form of energy which is received by a receiver located at some location remote from the endoscope, such is in the ceiling of the operating room, mounted on a tripod or the like, or in a wall. By analyzing the energy received from signal emitting elements, receiver calculates the attitude of the endoscope. [0038] Signal emitting elements may themselves generate the energy, such as in the case of light emitting diodes, magnets, or the like, or may comprise reflectors for reflecting energy emitted from some transmitting source located at some location remote from the endoscope, such is in the ceiling of the operating room, mounted on a tripod or the like, or in a wall. Transmitting source thus transmits energy, which is reflected off signal emitting elements, and is received by receiver. The energy may comprise, for example, infrared energy, light in the visual spectrum, magnetic energy, or the like. [0039] The present invention has been described above in terms of a presently preferred embodiment so that an understanding of the present invention can be conveyed. However, there are many alternative arrangements for a method for providing gravity referenced endoscopic image orientation not specifically described herein but with which the present invention is applicable. For example, and alternative mathematical framework describing the endoscope will lead to an alternative formula for the necessary orientation correction. In addition, while the examples were given with respect to endoscopes for use in surgical procedures, the present invention is equally applicable with respect to borescopes or the like for use within various mechanical structures. Therefore, the term “endoscope” as used herein, refers to an endoscope (used for medical procedures) or any similar device such as a borescope, a fiberscope, etc. [0040] This invention is not to be limited by the embodiments shown in the drawings and described in the description, which are given by way of example and not of limitation, but only in accordance with the scope of the appended claims.
A method is disclosed in for presenting an endoscopic image in an upright orientation. An electronic rotation pick-up means is fixed to the housing of an endoscope. The electronic rotation pick-up means produces signals indicating rotations of the endoscope. A microprocessor uses these signals to calculate a necessary amount of rotational correction for the endoscopic view orientation. The calculation includes factors to account for endoscope roll, endoscope pitch, and endoscope viewing direction. An image rotator rotates the endoscopic image by the calculated correction amount. The rotated image is displayed on a video display device.
0
CROSS-REFERENCE TO RELATED APPLICATION [0001] This application claims the priority of Provisional Application for Patent Ser. No. 60/897,456 filed on Jan. 25, 2007 which is incorporated herein by reference. FIELD OF INVENTION [0002] The present invention relates to a window shade or window covering utilizing a separator system for a control mechanism of the window shade or window covering. In particular, the present invention relates to a control mechanism for a window covering providing a disengagement function that may be utilized to prevent or minimize damage to the control mechanism as a result of unintended force on the window shade or window covering. BACKGROUND OF INVENTION [0003] There are numerous types of window shades and window coverings. Examples of such include Venetian blinds, Roman shades, and cellular shades. Typically such window shades and window coverings include a head rail having a light blocking or light shading element suspended from the head rail by one or more suspension cords. These window shades and window coverings also usually include a bottom rail that is also suspended from the head rail to provide additional weight to extend and straighten the light blocking or light shading element. Positioning of the suspension cords is adjustable through different mechanisms including cord locks, clutches, and winding drums. For example, with a clutch based control mechanism, a user controls the raising and lowering of the window covering by pulling on a control cord, which causes the clutch to drive the rotation of the clutch axle. Rotation of the clutch axle in one direction causes the suspension cords to unwind and lower the window covering. Raising of the window covering may be accomplished by applying an upward force to the bottom rail such that the clutch rotates the clutch axle in a second direction that winds the suspension cords and raises the window covering. [0004] A problem that occurs with window coverings utilizing a clutch control mechanism that has been observed is that the user sometimes will attempt to lower the window covering by pulling down on the bottom rail rather than by through use of the control cord. When a user pulls down on the bottom rail and forces the window covering closed in this manner, the clutch mechanism may be irreversibly damaged. [0005] What is needed is a device that provides for separating excessive force exerted directly on a window covering from the clutch control mechanism such that the damage that may be caused thereto is avoided. The present invention meets these desires and overcomes the shortcomings of the prior art. SUMMARY OF THE INVENTION [0006] The present invention is directed to a separation system for a control mechanism in a window covering. An embodiment of the present invention is a control mechanism including a torque-selective separator positioned on a drive axle upon which is also positioned a clutch mechanism. The drive axle comprises a clutch axle and a winding axle. [0007] The clutch mechanism may be a conventional clutch mechanism as is known in the art of window coverings. The clutch mechanism is preferably mounted about the clutch axle so as to cause the clutch axle to rotate in the desired manner. The clutch mechanism may also be connected to a control cord. When a user pulls on the control cord, the clutch causes the clutch axle to rotate. Under normal operating conditions, rotation of the clutch axle causes concurrent rotation of the winding axle such that the as the winding axle is rotated, the suspension cords are wound about one or more winding drums, and thereby, raising the window covering. Any clutch mechanism known or that may become known for use in a window covering may be utilized with the present invention. [0008] Mounted on and in a coaxial relationship with the drive axle is the separator system. The separator system is preferably formed from a body having a first portion and a second portion that are mated to one another to form the body. The body also comprises a first end and a second end. The first end defines a first recess that is configured to closely surround and circumscribe a distal end portion of the clutch axle. The second end similarly defines a second recess that is configured to closely surround and circumscribe a proximal end portion of the winding axle. Preferably, the first portion of the body and the second portion of the body each define a portion of the first and second recess. Preferably, the walls of the first and second recesses are rigid, and do not flex when force is exerted upon the walls. The first and second recess may be separated by a center partition if desired. [0009] It is preferred that the first and second recesses define a cross section that substantially matches the cross section of the portion of the drive axle, e.g., the clutch axle or winding axle, that is circumscribed. Preferably, the drive axle is non-resilient and does not compress when force is exerted upon the drive axle. Preferably, the drive axle does not contain a cavity or slot that would allow the width of the axle to be reduced in response to compression force. [0010] The drive axle and corresponding recess can define a cross section of any shape so long as the shape of the cross section creates a frictional force between the drive axle and recess when the drive axle is rotated. Such frictional force can be created from a variety of cross section components, including, but not limited to the corners of a polygonally shaped cross-section, the non-symmetrical sides of an oval-shaped cross-section, or ribs, teeth, or other protrusions projecting from a generally circular cross-section. [0011] The drive axle preferably defines a polygonal cross section. For example, the drive axle may define a square-shaped cross section. In this example, the first and second recesses would define a square-shaped cross section through which the drive axle is passed and closely circumscribed. The drive axle may also define a generally circular cross section, such as an oval-shaped cross section, in which case the first and second recesses would also define a generally circular cross section. The drive axle may also define a generally circular cross section with ribs, teeth or other protrusions projecting from its outer surface. In such a case, the first and second recesses would define a circular cross section containing slits, groves or other indentations that complement the protrusions of the projecting from the drive axle. [0012] Preferably, the first and second portions of the body provide equal portions of the recess such that the body is rotationally balanced about the drive axle. [0013] In some embodiments the cross section of the first and second recess need not match the cross section of the clutch axle or winding axle. Instead, for example, a square shaped cross section clutch axle and winding axle may be used with an octagonal recess. [0014] The first portion and the second portion of the body are movable relative to one another such that they are moveable from a mated position to an unmated position. In the mated position, the first portion and the second portion form the recess in the separator and are preferably held together by at least one biasing member, such as a spring clip. Any biasing members known in the art can be used to hold together the first portion and the second portion. Such biasing members include elastic bands, magnets, or any variety of spring. [0015] When the first portion and second portion of the body are in a mated position, the separator is preferably press fit with the drive axle. Under normal conditions, the press fit enables rotational force of the clutch axle to be transferred to the winding axle. As such, as the clutch is manipulated by the user through pulling on the control cord, the clutch axle is rotated, which causes concurrent rotation of the winding axle. [0016] As discussed above, a problem that has been observed occurs when a user attempts to lower the window covering by pulling on the bottom rail or accidentally pulls on the bottom rail. This excessive force on the bottom rail, in prior art systems, caused damage to the clutch mechanism. With the present invention, when an excessive force is exerted on the winding axle by way of a pulling force being exerted on the suspension cords, e.g., a user pulling on the bottom rail suspended by the suspension cords, the separator enables the force to not be exerted on the clutch mechanism. [0017] For example, when the first portion and second portion of the body are in a mated position, as a force is exerted on the winding axle, this force is transferred via the separator to the clutch axle and the clutch mechanism. If the amount of force exceeds a threshold level, which is less than the amount of force that would cause damage to the clutch, the winding axle is caused to rotate relative to the separator. As the winding axle rotates, due to the shape of the cross section thereof, the force exerted by the spring clip is overcome and the first portion and the second portion of the body are pried apart from one another and moved into an unmated position. As such, the winding axle is therefore able to rotate independent of the clutch axle, and the force exerted upon the winding axle is not transferred to the clutch axle or the clutch mechanism. [0018] In one embodiment, the cross sections of the clutch axle and the winding axle—as well as the first recess and the second recess—are of a regular polygon, such as a square. With the square-shaped cross section example, as the winding axle is rotated one quarter turn relative to the clutch axle, the spring clips cause the first and second portions of the body to return to a mated position. If the excessive force is still being exerted, the first and second portions of the body will again be pried apart and the winding axle rotated a quarter turn independent of the clutch axle, and then the body is returned to a mated position by the spring clips. This process continues until the force exerted on the winding drum does not exceed the threshold level. This threshold amount of force depends on the clutch mechanism in use. The threshold amount of force need only be less than whatever amount of force would cause damage to the clutch mechanism. [0019] In the embodiment discussed, the body of the separator is constructed with an assembly of two movable parts between which are defined the recesses for the axles. The number of parts can be any plurality desired. Also in the embodiment discussed, the clutch axle is detachably secured to the separator such that as the body is moved to an unmated position, the clutch axle can rotate relative to the separator. In an alternative embodiment, the clutch axle may be fixedly secured to the separator instead of by way of a press fit mount. In this alternative embodiment only the portion of the body that connects to the winding axle is moveable or adjustable to allow rotation of the winding axle relative to the separator, and in turn, relative to the clutch. [0020] In the previous embodiment, the coaction of the rotation of the winding axle and the compression of the spring clips cause the body of the separator to automatically move between a mated and an unmated position. In another alternative embodiment, the mechanism utilized to press fit the body to the axle may be releasable, yet not automatically re-engaged with the axle. In other words, if the threshold amount of force is exerted on the winding axle, the body of the separator is moved to an unmated position and thereby allowing the winding axle to rotate independent of the clutch axle, but is not caused to automatically return to a mated position. Instead, the reestablishment of the separator with the winding axle is achieved manually. [0021] The present invention has thus far been discussed in the context of a device utilized to prevent damage to a clutch mechanism. The present invention may also be used to provide a control mechanism for a window covering that may be operated either by a control cord, or by way of directly pulling or raising of the bottom rail, such as with a cordless window covering. In other words, the separator system may enable a user to pull down on the bottom rail of a window covering to lower the light blocking element, but not damage the clutch mechanism. Raising of the bottom rail is then achieved by applying an upward force to the bottom rail. If desired, the same control mechanism can include control cords to allow the user to raise and lower the window covering with the control cord. [0022] In yet another embodiment, the control mechanism may include a biasing mechanism such as found in cordless window covering applications. Examples of suitable devices are found in pending application Ser. No. 11/591,718, which was filed on Nov. 2, 2006 and application Ser. No. 11/392,340, which was filed on Mar. 29, 2006, each of which are incorporated herein by reference. An upward bias on the bottom rail and the commensurate rotational force on the winding axle may be provided by the biasing mechanism. When the user lifts directly on the bottom rail, the force exerted by the biasing mechanism may overcome the compressive force of the spring clips such that the winding axle is disengaged from the clutch axle, and the winding axle is then enabled to raised the window covering without transferring the rotational force to the clutch mechanism. BRIEF DESCRIPTION OF THE DRAWINGS [0023] In the drawings, [0024] FIG. 1 is a perspective view of a cellular window shade utilizing a separator system for a control mechanism in accordance with an embodiment of the present invention; [0025] FIG. 2 is a top plan view of a head rail of FIG. 1 ; [0026] FIG. 3 is a partial perspective view of the separator system engaged with the drive axle and in a mated position; [0027] FIG. 4 is a partial side elevational cross sectional view the separator system of FIG. 3 ; [0028] FIG. 5 is a partial perspective view of the separator system disengaged from the drive axle and in an unmated position; [0029] FIG. 6 is a partial side elevational cross sectional view the separator system of FIG. 5 ; [0030] FIG. 7 is side-elevation view of the separator system engaged with the drive axle and in a mated position wherein the drive axle and first recess have an oval shaped cross-section; [0031] FIG. 8 is a side-elevation view of the separator system shown in FIG. 7 disengaged from the drive axle and in an unmated position; [0032] FIG. 9 is side-elevation view of the separator system engaged with the drive axle and in a mated position wherein the drive axle has a generally circular cross-section containing U-shaped protrusions and the first recess has a generally circular cross-section with U-shaped indentations; and [0033] FIG. 10 is side-elevation view of the separator system engaged with the drive axle and in a mated position wherein the drive axle has a generally circular cross-section containing V-shaped protrusions and the first recess has a generally circular cross-section with V-shaped indentations. DESCRIPTION OF PREFERRED EMBODIMENT [0034] The invention disclosed herein is susceptible to embodiment in many different forms. The embodiment shown in the drawings and described in detail below is only for illustrative purposes. The disclosure is intended as an exemplification of the principles and features of the invention, but does not limit the invention to the illustrated embodiments. [0035] Referring to FIG. 1 , a cellular window 10 covering is shown. Window covering 10 includes a head rail 12 , a light blocking element, such as cellular structure 14 , a bottom rail 16 , a control cord 18 , and suspension cords (not shown). Window covering 10 may be opened by raising bottom rail 16 towards head rail 12 such that cellular structure 14 is collapsed and gathered on the bottom rail 16 . Raising of the bottom rail 16 may be effected by the user lifting the bottom rail such that the clutch mechanism ( FIG. 2 ) causes the suspension cords to be wound. Alternatively, the manipulation of the control cord 18 can be used to raise the bottom rail 16 . Lowering of the bottom rail 16 and closing of the window covering 10 may be done by manipulation of the control cord 18 , which causes the clutch mechanism to unwind the suspension cords, and thereby lower the bottom rail. [0036] As discussed, one problem that has been observed is that users of the window covering 10 sometimes attempt to close the window covering by pulling downward on bottom rail 16 . Conventional clutch mechanisms are typically designed to lock the window covering in a vertical position so that once positioned, the window covering does not close unintentionally. As such, if a user pulls too hard on the bottom rail, the resultant excessive force against the clutch lock can irreparably damage the clutch. [0037] Referring to FIG. 2 , an embodiment of the present invention that remedies the aforementioned problem is shown. Head rail 12 defines a channel in which various control components are located. Provided in the present embodiment is a drive axle comprising a winding axle 20 and a clutch axle 22 . The winding axle has mounted thereon a pair of winding drums 24 , 26 , which are supported by supports 28 and 30 . Winding axle 20 defines a proximal end portion 32 . Clutch axle 22 defines a proximal end portion 34 that is secured with clutch mechanism 36 , and a distal end portion 38 . The distal end portion 38 of the clutch axle 22 and the proximal end portion 32 of the winding axle are connected to one another by way of separator system 40 . In a preferred embodiment, the surface of the winding axle 20 and the clutch axle 22 is non-resilient and does not substantially compress when force is exerted upon it. [0038] A more detailed explanation of the separator system 40 is provided with reference to FIGS. 3-6 . Referring to FIGS. 3 and 4 , the separator system 40 is shown secured with winding axle 20 and clutch axle 22 . Separator system 40 includes a body 42 having a first portion 44 and a second portion 46 . Body 42 generally defines a first end 48 and a second end 50 . First portion 44 and second portion 46 are press fitted with the proximal end portion 32 of winding axle 20 and distal end portion 38 of clutch axle 22 by spring clips 52 and 54 . [0039] When first portion 44 and second portion 46 are in a mated position as shown in FIGS. 3 and 4 , body 42 defines a first recess 56 extending proximally from the first end 48 and a second recess 58 extending distally from the second end 50 . When in the mated position as shown, the first recess 56 and the second recess 58 define a square-shaped cross section. The cross section of the first recess 56 and the second recess 58 are configured to circumscribe the proximal end portion 32 of winding axle 20 and distal end portion 38 of clutch axle 22 , respectively. If desired, a partition 60 can be provided to separate the first recess 56 and the second recess 58 . In a preferred embodiment, the first recess 56 and second recess 58 contain rigid walls that do not flex when force is exerted upon the walls. [0040] When first portion 44 and second portion 46 are in a mated position, the body 42 of separator 40 connects the winding axle 20 and the clutch axle 22 such that force exerted on either of the winding axle 20 or clutch axle 22 is translated to the other. Thus, in normal operation, the winding axle 20 and clutch axle 22 function as an integral drive axle. [0041] Referring to FIGS. 5 and 6 , if a user exerts a pulling force on the bottom rail 16 ( FIG. 1 ) to cause it to lower, a resulting rotational force on winding axle 20 will drive the rotation of the winding axle 20 , causing the first portion 44 to separate from the second portion 46 of body 42 . Due to the geometries of the winding axle 20 , the clutch axle 22 , the first recess 56 , and the second recess 58 , if sufficient force is exerted, the compressive force of spring clips 52 and 54 are overcome. This allows first portion 44 of body 42 to separate from second portion 46 of body 42 . As such, winding axle 20 is permitted to rotate independent of the separator 40 , as well as the clutch axle 22 and clutch 36 . As the winding axle 20 continues to rotate, the geometry of first recess 56 is again brought into alignment with winding axle 20 , and spring clips 52 and 54 cause first portion 44 and second portion 46 to return to a mated position such as shown in FIGS. 3 and 4 . Guides 60 and 62 may be provided to assist in maintaining the desired alignment of the first portion 44 and the second portion 46 . If the excessive force is still being exerted, the first portion 44 and second portion 46 of the body 42 will again be pried apart and the winding axle 20 rotated a quarter turn independent of the clutch axle 22 , and then the body 42 is returned to a mated position by the spring clips 52 and 54 . This process continues until the force exerted on the winding drum does not exceed the threshold level. Once the excessive force is removed, the first portion 44 and second portion 46 of body 42 stay in a mated position and the clutch axle 22 and winding axle 20 again are connected so as to rotate synchronously. The force exerted by spring clips 52 and 54 in this embodiment can be provided by other mechanisms such as elastic bands, magnets, or springs. [0042] Referring to FIGS. 7 and 8 , an alternative embodiment of the separator system 40 is shown with an oval-shaped winding axle 120 . The oval-shaped first recess 156 in this embodiment corresponds to the shape of the winding axle 120 . The clutch axle and second recess (not shown) of this embodiment may also be oval shaped to create a consistent shape on both sides of the separator 40 . [0043] In this embodiment, a rotational force on winding axle 120 in the direction of arrow A or in the direction opposite to arrow A will cause first portion 144 to move in the direction of arrow B and will cause second portion 146 to move in the direction of arrow C. Such movement creates a separation between first portion 144 and second portion 146 such that oval-shaped winding axle 120 is permitted to rotate independent of separator 40 . [0044] Referring to FIG. 9 , an alternative embodiment of the separator system 40 is shown with a winding axle 220 having a generally circular cross-section. U-shaped protrusions 250 and 252 extend from winding axle 220 . The generally circular-shaped first recess 256 of this embodiment contains U-shaped indentations 258 and 260 that correspond to the U-shaped protrusions 250 and 252 . [0045] Referring to FIG. 10 , another alternative embodiment of the separator system 40 is shown with a winding axle 320 having generally circular cross-section. V-shaped protrusions 350 and 352 extend from winding axle 320 . The generally circular-shaped first recess 356 of this embodiment contains U-shaped indentations 358 and 360 that correspond to the V-shaped protrusions 350 and 352 . [0046] The positioning of the protrusions is not limited to the positions described in the disclosed embodiments. The protrusions 250 , 252 and 350 , 352 shown in FIGS. 9 and 10 are located on opposite sides of the winding axle 220 , 320 . The protrusions can also be placed less than 180 degrees apart from each other. Alternatively, one protrusion or more than two protrusions can extend from the winding axle. The indentations in the first recess may also be positioned to correspond with the alternative protrusion placement. [0047] While the embodiments discussed include axles and recesses with square, oval, or circular cross-sections, other shapes can be used. For example, polygonal shapes such as hexagons or octagons can be used. Other generally circular or generally polygonal shapes can be used so long as the shape of the cross section creates a frictional force between the drive axle and recess when the drive axle is rotated. [0048] Although the embodiments discussed describe a spring clip used as a biasing member, other biasing members known in the art can be used to hold together the first portion and the second portion. Such biasing members include elastic bands, magnets, or any variety of spring, including leaf springs, coil springs, and torsion springs. [0049] Another embodiment of the present invention can contain no biasing member at all, such that the body does not automatically re-engage with the axle after the body has been released. In this alternative embodiment, the reestablishment of the separator with the winding axle is achieved manually. [0050] Also, the embodiments discussed describe a separator system wherein the winding axle is disengageable from the separator system. It is also contemplated that the winding axle may be fixedly secured with the separator system, yet the clutch axle may be detachably secured with the separator system. In this configuration, if the rotational force exceeds the threshold level, the winding axle and separator system continue to rotate together while disengaged from the clutch axle. [0051] The foregoing description and the drawings are illustrative of the present invention and are not to be taken as limiting. Other arrangements of the engagement structure may be implemented. Such variations and modifications are within the spirit and the scope of the present invention and will be readily apparent to those skilled in the art in view of the scope of the invention as claimed herein.
The present invention relates to a window shade or a window covering having a control mechanism for raising and lowering the window covering. The control mechanism is provided with a separator system. In particular, the present invention relates to a control mechanism with a separator system that provides a disengagement function to prevent or minimize damage to the control mechanism as a result of unintended force on the window shade or window covering. The separator system utilizes a body movable between a mated position where a clutch axle and a winding axle move synchronously, and an unmated position where the winding axle is allowed to rotate independent of the clutch axle.
4
FIELD OF THE INVENTION [0001] The present invention relates generally to brake systems for vehicles, and more particularly to brake systems for use in an aircraft. BACKGROUND OF THE INVENTION [0002] Various types of braking systems are known. For example, hydraulic, pneumatic and electromechanical braking systems have been developed for different applications. [0003] An aircraft presents a unique set of operational and safety issues. For example, uncommanded braking due to failure can be dangerous to an aircraft during takeoff. On the other hand, it is similarly necessary to have virtually fail-proof braking available when needed (e.g., during landing). Moreover, it is important that braking be effected promptly and reliably. [0004] A typical hydraulic brake system, for example, may include the following components among others: a pressure source, a brake actuator for exerting a braking force on a wheel as a result of pressure provided by the pressure source, a valve for controlling an amount of pressure provided from the pressure source to the actuator in response to a command signal, a controller for outputting the command signal in response to system inputs provided to the controller, and a wheel speed sensor. In many such systems, the system inputs include both operator input (e.g., depression of a brake pedal), and measured pressure or force applied to the actuator in response to the operator input. SUMMARY OF THE INVENTION [0005] When an operator initially requests braking and pressurized fluid is first applied to the actuator, typically there will be some displacement of the brake components prior to force being exerted on the brake material. Consequently, the initial measured pressure or force can be very low for a period of time until braking force is actually applied. Thus, there may be a period of time when the brake command signal does not produce a brake response. [0006] This condition is sometimes referred to as brake fill and, as the controller continues to ask for brake output increases without any measurable result (e.g., braking requested but brake not yet responding with braking action), the brake command signal increases. This can occur, for example, if the controller includes an integrator that accumulates the product of error and time. Therefore, as time passes without error reduction (e.g., no brake response yet) a controller with an integrator or integral action continues to increase its output. Once the brake does finally respond to the command signal (e.g., develops braking torque), the brake responds to the increased command signal. This increased command signal is typically more braking than is desired but is the result of the accumulated error during the brake fill condition. As a consequence of the increased command signal, braking action is finally produced but at an elevated level. The controller then must rid itself of the extra accumulated error before resuming more typical braking levels. [0007] Accordingly, such application of the brakes can result in grabbing or jerky brake performance. This can occur in any type of braking system (e.g., hydraulic, pneumatic, electromechanical, etc.). In an electric brake, for example, the condition can occur as an actuator travels from its retracted position to a position engaging a brake stack. [0008] The invention provides a brake fill effect minimization function for preventing or reducing controller windup during a brake fill condition or the like that may commonly occur in hydraulically actuated brakes as well as electromechanically actuated brakes. The function temporarily reduces error input to a controller during perceived brake fill (or running clearance) conditions thereby facilitating smooth application of the brakes during initial braking and/or under anti-skid conditions. [0009] Accordingly, a system for controlling a braking torque applied to a wheel of a vehicle comprises a power source, at least one brake actuator for exerting a braking force on a wheel as a result of power provided by the power source, a feedback controller having an input for receiving a brake command signal and an output for providing a brake control signal for controlling application of a brake torque to the wheel, and a sensor for measuring an effect resulting from an amount of power supplied to the brake actuator and feeding back a signal to the controller indicative of the supplied pressure. The controller is configured to adjust the brake control signal using the signal fed back from the sensor to limit a degree of feedback control when the difference between a projected power and the supplied power exceeds a first threshold value. [0010] The controller can apply open loop control without the pressure feedback control when the difference between the projected power and the supplied power exceeds a second threshold value greater than the first threshold value. [0011] The controller can scale the error between the projected power and the supplied power when the difference between the projected power and the supplied power is between a first threshold value and a second threshold value, and the scaled error can be used for feedback control. The power source can be a hydraulic power source, and the brake output command can be operative to control a pressure control valve to supply a desired pressure to a hydraulic brake actuator. Alternatively, the power source can be an electric power source, and the brake output command can be operative to supply a current to an electromechanical brake actuator. [0012] In accordance with another aspect, a method for controlling a braking torque applied to a wheel of a vehicle by a braking system, said braking system including a power source and at least one brake actuator for exerting a braking force on a wheel as a result of power provided by the power source, the method comprises the steps of receiving a brake command signal indicative of a desired amount of braking to be applied to the wheel, and providing a brake output control signal to control an amount of power supplied to a brake actuator assembly by the power supply, measuring an effect of an amount of power supplied to the actuator assembly and performing feedback control of the brake pressure output signal using a signal indicative of the amount of supplied power, adjusting the brake output control signal using the feedback control based on the amount of supplied power, and limiting a degree of feedback control when the difference between a projected power and the supplied power exceeds a first threshold value. [0013] The method can further comprise applying open loop control without the feedback control when the difference between a projected power and the supplied power exceeds a second threshold value greater than the first threshold value. In addition, the method can include scaling the error between the projected power and the supplied power when the difference between the projected power and the supplied power is between a first threshold value and a second threshold value, and using the scaled error to perform feedback control of the output control signal. [0014] In accordance with another aspect, a device for providing a brake fill minimization function for a brake system that controls brakes based on a feedback control parameter related to measured power supplied to a brake actuator, said device being configured to receive a signal indicative of a desired amount of braking to be applied, generate a brake output control signal for controlling an amount of power to be supplied to the actuator to effect braking, receive a signal indicative of an effect of the amount of supplied power, compare the supplied power to a projected power, and limit a degree of feedback control when the difference between the projected power and the supplied power exceeds a first threshold value. [0015] The device can be configured to apply open loop control without pressure feedback control when the difference between the projected power and the supplied power exceeds a second threshold value greater than the first threshold value, and/or further configured to scale the error between the projected power and the supplied power when the difference between the projected power and the supplied power is between a first threshold value and a second threshold value, and wherein the scaled error is used by the controller for feedback control. The device can be incorporated into a brake system control unit (BSCU) of a brake system. [0016] Further features of the invention will become apparent from the following detailed description when considered in conjunction with the drawings. BRIEF DESCRIPTION OF THE DRAWINGS [0017] FIG. 1 is a schematic diagram of a hydraulic brake system. [0018] FIG. 2 is a schematic diagram of an exemplary hydraulic brake system including a brake fill effect minimization function in accordance with the invention. [0019] FIG. 3 is an control block diagram illustrating the brake fill effect minimization function. [0020] FIG. 4 is a flow chart illustrating the brake fill effect minimization function. DETAILED DESCRIPTION [0021] The present invention will now be described with reference to the drawings, wherein like reference numerals are used to refer to like elements throughout. [0022] Referring initially to FIG. 1 , a conventional hydraulic brake control system as used in an aircraft is generally designated 10 . Generally speaking, brake control on an aircraft is usually structured in a paired wheel configuration for functional modularity. For example, if the aircraft has two wheels on the left side of the aircraft and two wheels on the right side, the outer two wheels form a pair and the inner two wheels form another pair. Within a pair, there is a right wheel control and left wheel control. [0023] The left and right wheel control functions are uncoupled except possibly for locked wheel protection. The basic unit therefore consists of a control for a single wheel that can be left or right. As utilized herein, it will be appreciated that the term “wheel” is intended to refer collectively to both the wheel and tire. [0024] For sake of simplicity, the brake control system 10 (also referred to herein as system 10 ) as shown in FIG. 1 represents the basic unit for providing brake control of a single wheel (e.g., left or right). However, it will be appreciated that control for the other wheel(s) can be provided via a corresponding system(s) 10 or in a single system incorporating the same inventive principles. Moreover, the present invention as described provides brake control in connection with an aircraft. Nevertheless, it will be appreciated that the brake control system 10 including a brake fill effect minimization function according to the present invention has utility for virtually any type of vehicle and is not limited necessarily to brake control for aircraft. Further, the brake control system according to the present invention could also be used in a test environment with brake dynamometers, for example. [0025] The system 10 includes a pilot input device in the form of pedal 14 and an LVDT 16 for measuring brake pedal displacement and sending a pilot commanded signal P c to a brake system control unit BSCU 18 . Specifically, the BSCU 18 interprets the pedal displacement as a command for appropriate control mode and sends a brake pressure output command signal P 0 in the form of a valve current to a brake pressure control valve 20 that is configured to modulate pressure supplied to a brake actuator 22 from a brake power source 24 . The brake assembly 28 in turn provides braking action to wheel 30 by exerting a braking torque or force on the wheel 30 as is conventional. The wheel 30 is coupled to the aircraft (or other vehicle) via a conventional structure (not shown). [0026] The system 10 can further include a wheel speed sensor and/or brake torque sensor 34 that measures the wheel speed and/or the amount of torque exerted by the brake actuator 22 and brake assembly 28 on the wheel 30 . The wheel speed and/or brake torque sensor 34 can be any suitable type of sensor that provides an output signal (e.g., measured torque signal T m ) indicative of the braking torque and/or speed of the wheel 30 . The measured torque signal T m , for example, can be supplied to the controller 18 for use as an input to the brake controller 18 in some applications. [0027] The system 10 further includes pressure sensor 38 that measures the pressure applied to the brake actuator 22 . The pressure sensor 38 may be any conventional pressure sensor. The output of the pressure sensor 38 , measured pressure signal P m , represents the pressure supplied to the brake actuator 22 . The measured pressure signal P m is fed back to the BSCU 18 and is used as an input to the brake controller 18 representative of the applied pressure. In an electromechanical brake system, a load cell present within the actuator or the observer output within the actuator control (estimating force from actuator current and position) would provide a measurement of actuator force that could be used, as will be appreciated, in place of the P m signal in the brake fill effect minimization function as described below. [0028] Generally describing the operation of the system 10 , during a braking event the pilot of the aircraft activates the brakes by depressing the pedal 14 (or its equivalent). The depression of the pedal 14 is converted to an electrical signal (command pressure signal P c ) by LVDT 16 that is provided to the BSCU 18 . The value of the command pressure signal P c is indicative of the degree of depression of the pedal, and is related to the amount of braking commanded by the pilot. The BSCU 18 uses the command pressure signal P c to derive a suitable brake pressure output command signal P o . It will be appreciated that the brake pressure output command signal P o may be a valve current for a hydraulic brake or a force signal in the case of an electromechanical brake, for example. [0029] The brake pressure output command signal P o (e.g., valve current) is input to the pressure control valve 20 which then applies a desired pressure to the actuator 22 . The brake actuator 22 in turn applies pressure to the brake assembly 28 based on the brake pressure output from the control valve 20 in a conventional manner. The applied brake pressure creates a torque which results in a reduction in the rotational speed of the wheel 30 which is measured by the wheel speed/brake torque sensor 34 and fed back to the BSCU 18 . Utilizing the measured pressure signal P m and comparing it to the pilot commanded pressure P c and/or measured torque T m , the BSCU 18 computes a projected pressure to apply an appropriate amount of braking force to the wheel. [0030] For example, as will be described more fully below in connection with FIG. 2 , if the measured pressure signal P m is greater than the command signal P c , the BSCU 18 reduces the value of the brake pressure output command signal P o fed to control valve 20 to reduce braking. In the event the measured pressure signal P m is less than the command pressure signal P c , the BSCU 18 will increase the value of the brake pressure output command signal P o fed to control valve 20 to increase braking. [0031] As will be appreciated, in a hydraulically actuated system such as described, the time to fill the hydraulic cavity of the actuator can have negative impacts on overall system performance, particularly during low commanded pressure (e.g., initial braking application) and low runway coefficient of friction (e.g., anti-skid) conditions such as commonly occur on an icy runway. A similar effect can occur with both electromechanical and pneumatic actuators upon initial brake application during clearance take-up as well on icy runways, for example. [0032] For example, during initial braking application as the pilot commanded pressure P c increases beyond contact pressure, the brake-fill effect causes the difference between the commanded pressure P c and the measured pressure P m to increase. Thus, the brake-fill condition increases the time before the measured brake pressure P m begins responding to the pilot's commanded pressure P c . As a result, a conventional BSCU would begin ramping the output pressure signal P o upward to minimize the error between the measured and commanded pressures P m and P c . In control terminology, the brake-fill phenomena represents a source of brake controller wind-up. When the brake fill condition terminates, the measured pressure signal P m begins responding to the previously increasing control signal P o . As a consequence, the measured brake pressure P m increases in an undesired manner which can often be observed as grabbing or jerky brake performance. [0033] Turning to FIG. 2 , a brake system 50 including a brake-fill effect minimization function in accordance with the invention is illustrated. The system 50 generally includes the same components as the system 10 of FIG. 1 including a BSCU 54 for receiving a brake command from a pilot via an LVDT or the like (not shown in FIG. 2 ). The BSCU 54 generates a brake control output P o that drives valve drive circuitry 60 . A brake control valve 58 receives a brake valve current C bcv from valve drive circuitry 60 and, in response thereto, supplies hydraulic fluid to a brake actuator 62 configured to apply force to a brake stack 66 for braking a wheel 70 . A pressure sensor 74 senses the pressure supplied to the actuator 62 and feeds a corresponding signal back to the BSCU 54 . A wheel speed sensor 78 senses wheel speed and feeds a corresponding signal W s back to the BSCU 54 as well. [0034] A microprocessor of the BSCU 54 in this embodiment executes a brake control algorithm BCA 82 including the brake fill minimization function in accordance with the invention. The microprocessor accesses external signals using the BSCU 54 electrical circuitry as will be described. The primary BCA signals include pedal deflection, wheel speed as sensed by the wheel speed sensor 78 , brake line pressure as sensed by the pressure sensor 74 , brake output command signal P o and brake control valve current C bcv . [0035] During operation, pedal deflection is interpreted by the BCA 82 as setting a desired amount of pressure (known as a reference command). The BCA 82 computes output commands P o used to create brake control valve currents C bcv which result in brake pressure and brake torque to achieve wheel deceleration targets. [0036] When this projected pressure P prj differs from the measured pressure P m by a key threshold, then the BCA 82 error signal (e.g., reference speed minus measured speed) is scaled. This scaled error reduces the integrator windup so that when the actuator 62 contacts the brake stack 66 the controller output command hasn't increased dramatically. Accordingly, the time to achieve nominal controller operation under such conditions is improved. [0037] The error scaling generally occurs only when the measured pressure P m is between minimum and maximum pressure thresholds. The minimum threshold exists so that actuator 62 can initialize motion leading to the actuator 62 contact with the brake stack 66 . The maximum threshold exists to focus the minimization function activity to the brake fill delay (and not actuator response lag, for example). [0038] Accordingly, the brake fill minimization function generally operates by identifying the occurrence of a brake fill condition by comparing the projected pressure to the measured pressure, and responding to such condition by scaling the error between the brake command pressure and the measured pressure. [0039] With reference to FIG. 3 , a feedback block diagram of the function is indicated generally by reference numeral 100 . This diagram shows a simple feedback block diagram of a single wheel brake control system 102 , 106 , 108 , 110 and 112 with the brake fill minimization function 114 and 117 . The single wheel brake control system functions generally as follows. [0040] Pedal deflection is interpreted as desired wheel speed reference signal 101 by the BCA. This wheel speed reference is processed by the system W 102 to produce the reference speed 103 used by the antiskid/decel control system. This reference speed is compared with the filtered measured wheel signal 113 . The difference between the reference and measured wheel speed forms the error signal 104 . [0041] This error signal 104 is the signal which the brake fill minimization function may reduce or scale before passing the signal onto the controller 106 . The controller computes a brake command signal (u; 107 ) which is used to create a valve current for the actuation system 108 . The actuation subsystem includes BSCU circuitry, hydraulic valves, hydraulic lines, and the brake line pressure sensor. The actuation system output and input to the plant system (P; 110 ) is brake pressure 109 . The plant system includes the brake, wheel, tire, tire/runway interface. Within the plant system the pressure input is converted to brake torque which decelerates the wheel and aircraft. The wheel speed 111 is measured and processed by the sensor subsystem (M; 112 ). This is the same signal used to compute the error signal for the controller and forms the feedback loop used to implement antiskid/decel control. [0042] The brake fill minimization function monitors brake pressure performance and scales the control input error when brake performance is not desirable. The minimization function uses the measured brake pressure 109 and a projected brake pressure to determine brake performance. The projected brake pressure 115 uses the brake command signal 107 from the controller to compute the expected brake pressure. [0043] This computation can be based on input-output performance data for the actuation system (e.g., open loop current to pressure relationship for the BCV 58 ). The difference 116 between the measured and projected pressure is input to the scaling system 117 . The scaling subsystem uses the absolute value of the projected error 116 to compute the amount of scaling 105 to apply to the controller input error. When brake performance is good (e.g., small projected error) there is small scaling applied to the error signal. When brake performance is bad (e.g., brake fill effect creates a larger projected error) then more scaling is applied to the controller error. [0044] Turning to FIG. 4 , a flow diagram for the brake fill effect minimization function is illustrated and indicated generally by reference numeral 200 . As will be appreciated, this function 200 includes several functions (projected pressure, scaling function) and tuning parameters (Pmin, Pmax, Smin, Smax, emin, emax). These functions and parameters depend on the particular dynamic properties of the brake and aircraft being considered. Each sample or calculated controller update considers the above flow diagram. [0045] The process starts at process step 201 with the comparison of the measured brake pressure P m against a minimum brake pressure, P min . This minimum brake pressure exists to ensure that sufficient brake pressure is applied to initiate the process of brake fill (or running clearance closure for an electric brake). Without this condition, the function 200 could keep the brake fixed at zero pressure and no braking would occur. No other function processing occurs if the measured brake pressure fails this condition. [0046] If P m is greater than P min , then in process step 202 the measured brake pressure P m is compared with a maximum brake pressure, P max . This pressure exists to prevent the minimization function from being applied to a condition unlikely to be brake fill. Since brake fill phenomenon is isolated to a low pressure range, this maximum pressure bounds the pressure (or electric actuator position for an electric brake) over which the phenomenon is expected to occur. [0047] If the measured brake pressure P m is within the appropriate range defined by the previous two conditionals, then the projected pressure P prj and projected error e prj are calculated in process steps 203 and 204 , respectively. The projected brake pressure P prj is computed using the dynamic relationship between the brake command variable, BCA output variable, and brake pressure. This provides an estimation (without the influence of brake fill) of the brake pressure performance. Therefore, when compared to the measured pressure P m , any significantly large difference is likely the result of brake fill. Brake fill differences can occur during the initial application of pressure or when pressure oscillates (e.g., due to antiskid pressure cycling) near contact pressure. Therefore, the difference between projected P prj and measured pressures P m can be positive or negative while experiencing the effects of brake fill. [0048] The detection of brake fill phenomena generally relies more upon the magnitude of the error than the sign of the error. As a result, the brake fill minimization function 200 considers the absolute value of the difference between the projected P pr , and measured pressures P m . [0049] In process step 205 , the magnitude of the projected error e prj is compared against the maximum error bound, e max . This error bound represents a minimum error level caused by the brake fill effect. Therefore, if the error exceeds this boundary then there is a strong indication the brake is experiencing brake fill. When the projected error e prj exceeds this bound the controller input error is scaled by the maximum amount in process step 206 (specified by S min ). This provides the controller a reduced error and slows integral term output signal growth during periods of brake fill. [0050] If the error e prj does not exceed e max in process step 205 , then the magnitude of the projected error e prj is compared in process step 207 against the minimum error bound, e min . This error bound represents the condition without any error caused by the brake fill effect. Therefore, minimal scaling of the controller input error is required. When the projected error e prj is less than this bound, the controller input error is scaled by the minimum amount in process step 208 (specified by S min and generally equal to one). This provides the controller an essentially unaltered error. [0051] If the projected error e prj is between the minimum and maximum error bounds, then the scaling is determined by a linear function, for example, in process step 209 . The output of this linear function is bounded by the scaling of the previous to conditions and is specified by the following equation: [0000] S = ( S max - S min e min - e max )  e prj + ( S min  e min - S max  e max e min - e max ) [0000] As will be appreciated, the scaling could be performed in accordance with a wide range of functions of various orders, as desired. [0052] As will further be appreciated, the brake system described above may operate in two modes: antiskid/Decel Control Mode and Pressure Control Mode. In Antiskid/Decel Control Mode, pedal deflection is interpreted as setting a deceleration target. The antiskid/deceleration controller computes output commands to achieve wheel speed/deceleration targets (without explicit concern for pressure). The brake minimization function uses open loop relationships between the antiskid/deceleration controller's output command and pressure to compute a projected pressure. When the projected pressure differs from the measured pressure by a key amount of pressure then the antiskid/decel controller error signal is scaled. The scaled error reduces the integrator windup so that when the actuator does contact the brake stack the controller output command hasn't increased as much. [0053] In Pressure Control Mode operation the pedal deflection is interpreted as setting a brake pressure target. This brake pressure target is the projected pressure target during this control mode. When the projected pressure differs from the measured pressure by a key amount the pressure controller error signal is scaled. [0054] Although described chiefly in the context of a hydraulic brake, it will be appreciated that aspects of the invention can be applied to electric brakes as well. As noted, in an electric brake a brake fill-like condition can occur when a brake actuator is running clearance prior to engaging a brake stack. This clearance take-up produces essentially the same effect as a brake fill condition in a hydraulic brake and can be minimized as described above by sensing the condition and scaling the input error. [0055] As used in this description, the terms power and/or power source includes hydraulic power sources and power, electric power sources and power, and/or pneumatic power sources and power. In the context of a hydraulic or pneumatic system, an effect resulting from power supplied to an actuator includes hydraulic or pneumatic pressure. In the context of an electric system, an effect of power supplied to an actuator includes electric current [0056] Although the invention has been shown and described with respect to a certain preferred embodiment or embodiments, it is obvious that equivalent alterations and modifications will occur to others skilled in the art upon the reading and understanding of this specification and the annexed drawings. In particular regard to the various functions performed by the above described elements (components, assemblies, devices, compositions, etc.), the terms (including a reference to a “means”) used to describe such elements are intended to correspond, unless otherwise indicated, to any element which performs the specified function of the described element (i.e., that is functionally equivalent), even though not structurally equivalent to the disclosed structure which performs the function in the herein illustrated exemplary embodiment or embodiments of the invention. In addition, while a particular feature of the invention may have been described above with respect to only one or more of several illustrated embodiments, such feature may be combined with one or more other features of the other embodiments, as may be desired and advantageous for any given or particular application.
A brake fill effect minimization function for preventing or reducing brake controller windup during a brake fill condition or the like that may commonly occur in hydraulic or electromechanical brake systems, particularly during initial application of the brakes or during anti-skid conditions. The function temporarily reduces error input to the brake controller during a perceived brake fill condition (hydraulic brakes) or running clearance condition (electromechanical brakes) thereby facilitating smooth application of the brakes during initial braking and/or under anti-skid conditions.
1
FIELD OF THE INVENTION [0001] The present invention is directed to a structural element and/or floor structure for a cargo-carrying vehicle. More specifically, the present invention provides a composite floor structure for a truck and/or trailer having a reduced weight, enhanced resistance to harsh environmental conditions, high strength, and high load-bearing capacity. BACKGROUND OF THE INVENTION [0002] Flat-bed truck bodies and/or cargo trailers are often produced with an exposed frame portion upon which a floor structure is applied for carrying loads. Conventional floor structures produced for cargo vehicles are constructed from a frame of steel channels or I-beams overlaid with plywood sheet, wherein the steel tubing is affixed to the vehicle frame (via fasteners and/or welds) and wherein the plywood sheet serves as the cargo floor. In many cases, the steel tubing is welded to form a steel ladder frame that is bolted to the plywood sheet floor to form the floor structure. [0003] The steel and plywood components of conventional cargo floor structures, while relatively easy to obtain and modify to form a robust cargo floor, suffer from several shortcomings. For example, the steel channels and/or I-beams (which are in many cases 3 inches tall) and plywood (which is often 1 inch or more thick) used to construct conventional floor structures are relatively heavy materials, and thus add to the empty weight of a cargo vehicle. Such extra weight reduces the fuel economy and decreases the effective cargo capacity of the cargo vehicle. The added empty weight of cargo vehicles equipped with conventional cargo floor structures also increases wear on vehicle components, such as suspension systems and/or tires. All of these issues may result in extra costs for operators of such cargo vehicles, especially in cases where such cargo vehicles are expected to carry relatively heavy cargo loads over long distances. [0004] The steel and wood components of conventional cargo floor structures may also be especially vulnerable to the degrading influences of the weather and/or environmental conditions to which the floor structures may be exposed on a daily basis. For example, plywood floor structures may deteriorate due to rot, weather exposure, and/or insect infestation. Such deterioration may be especially prevalent where the vehicle is stored outdoors at a cargo depot and/or a cargo truck terminal for extended periods. In addition, the steel frame structure may rust. Frame rust may be particularly problematic in cargo vehicles operated in coastal environments (which may be subjected to salt water exposure) and/or cargo vehicles used in cold climates (where the frame may be subjected to exposure to road salt and/or slag used to treat roads covered in ice and snow). [0005] Although conventional cargo floor structures suffer from the disadvantages outlined above, their use is still prevalent in flat-bed cargo vehicle applications primarily due to availability, relative ease of assembly and adjustability, and because the use of such conventional floor structures is relatively consistent and well-known. However, in light of the shortcomings of these conventional cargo floor structures, there exists a need in the art for cargo floor structures that: (1) minimize the empty weight of the cargo vehicles in which they are used while still providing a durable, heavy-duty load-carrying capacity; and (2) provide a cargo floor structure that may be utilized daily in harsh environmental conditions without suffering significant deterioration due to exposure to such harsh conditions. BRIEF SUMMARY OF THE INVENTION [0006] The embodiments of the present invention satisfy the needs listed above and provide other advantages as described below. Embodiments of the present invention may include a composite cargo floor assembly. In some embodiments, the cargo floor assembly may comprise a floor member having a load-bearing surface and a mating surface opposite the load bearing surface, wherein the floor member may be formed substantially from a first composite material. The assembly may also comprise, in some embodiments, a support frame operably engaged with the mating surface of the floor member, wherein the support frame includes a first plurality of cross members extending in spaced relation in a first direction and a second plurality of cross members extending in spaced relation in a second direction such that the first and second plurality of cross members intersect and interconnect to form the support frame. In addition, the cross members may be formed substantially from a second composite material such that the cargo floor assembly has a reduced weight and an enhanced load-bearing capacity. In some embodiments, the floor assembly may further comprise an adhesive layer disposed between the mating surface of the floor member and the support frame for operably engaging the mating surface to the support frame to form the cargo floor assembly. [0007] According to some other embodiments of the present invention, the first and second plurality of cross members forming the support frame may have a substantially rectangular cross-section. In some embodiments, the cross members may also be substantially hollow. Furthermore, the cross members may also, in some embodiments, define a plurality of apertures for receiving a corresponding plurality of fasteners for operably engaging the support frame with a frame of a vehicle (such as, for example, a flat-bed truck and/or cargo trailer). [0008] Furthermore, in some assembly embodiments of the present invention, the second composite material of the first and second plurality of cross members may include, but is not limited to: a pultruded tubing material; a pultruded composite tubing; a composite tubing material comprising a polyurethane matrix and a plurality of E-glass fibers disposed within the polyurethane matrix; and combinations of such composite material components. [0009] In some cargo floor assembly embodiments of the present invention, the first composite material of the floor member may include, but is not limited to: a fiber reinforced polymer material; a fiber reinforced polymer composite; and a solid laminate. In some embodiments, wherein the first composite material comprises a fiber reinforced polymer composite, the fiber reinforced polymer composite may include, but is not limited to: a pultruded sandwich panel comprising an upper skin and a lower skin and a core disposed substantially between the upper and lower skins; a vacuum-infused sandwich panel comprising an upper skin and a lower skin and a core disposed substantially between the upper and lower skins; a pultruded panel comprising an upper skin and a lower skin and a web material disposed substantially between the upper and lower skins; and combinations of such fiber-reinforced polymer composites. [0010] In other assembly embodiments, the floor member may be substantially rectangular in shape and may further define at least one notch at a corner of the floor member for receiving a corner post adapted to extend substantially vertically from the load bearing surface of the floor member. Some additional embodiments may comprise a floor member having a substantially rectangular shape that may comprise at least one bracket extending substantially vertically from at least one edge of the floor member. In such embodiments, the bracket may be adapted to receive a side wall adapted to extend substantially vertically from the load bearing surface. Furthermore, in some such embodiments, the bracket may be integrally formed with the floor member. [0011] Thus the various embodiments of the present invention provide many advantages that may include, but are not limited to: providing a relatively lightweight and durable composite cargo floor structure that may be easily affixed to a cargo vehicle frame; and providing a composite cargo floor structure that may be more resistant to deteriorating environmental forces when compared to conventional cargo floor structures. These advantages, and others that will be evident to those skilled in the art, are provided in the various embodiments of the present invention. BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS [0012] Having thus described the invention in general terms, reference will now be made to the accompanying drawings, which are not necessarily drawn to scale, and wherein: [0013] FIG. 1 is an underside perspective view of a composite cargo floor assembly according to one embodiment of the present invention; [0014] FIG. 2 is an underside view of a support frame and the mating surface of a floor member according to one embodiment of a composite cargo floor assembly of the present invention; [0015] FIG. 3 is a top view of the load-bearing surface of a floor member according to one embodiment of a composite cargo floor assembly of the present invention; and [0016] FIG. 4 is a perspective view of a composite cargo floor assembly including brackets operably engaged with the floor member for receiving a side wall adapted to extend substantially vertically from the load bearing surface, according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION [0017] The present inventions now will be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all embodiments of the inventions are shown. Indeed, these inventions may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Like numbers refer to like elements throughout. The singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise. [0018] Although the preferred embodiments of the invention described herein are directed to a composite cargo floor assembly for attachment to a truck body, it will be appreciated by one skilled in the art that the invention is not so limited. For example, embodiments of the composite cargo floor assembly of the present invention can also be incorporated into various other types of cargo vehicles including, but not limited to: cargo trailers, railcars, maritime cargo containers, and other cargo vehicles and/or containers. [0019] Referring to FIG. 1 , one embodiment of the present invention provides a composite cargo floor assembly 10 comprising a floor member having a load-bearing surface 12 (see FIG. 3 ) and a mating surface 11 opposite the load bearing surface 12 . According to some embodiments, the assembly 10 may also comprise a support frame 20 operably engaged with a mating surface 11 of the floor member. The support frame 20 may be operably engaged with the mating surface 11 of the floor member and may include a first plurality of cross members 21 extending in spaced relation in a first direction and a second plurality of cross members 22 extending in spaced relation in a second direction such that the first and second plurality of cross members 21 , 22 intersect and interconnect to form the support frame 20 . [0020] According to some embodiments of the composite cargo floor assembly 10 of the present invention, the floor member may be formed of a first composite material that may include, but is not limited to: a fiber reinforced polymer material; a fiber reinforced polymer composite; and a solid laminate. In some embodiments, the fiber reinforced polymer composite may comprise a pultruded sandwich panel comprising an upper skin and a lower skin and a core material disposed substantially between the upper and lower skins. Other fiber reinforced polymer composites may include a vacuum-infused sandwich panel comprising an upper skin and a lower skin and a core material disposed substantially between the upper and lower skins. [0021] Exemplary core materials of the first composite material may include, but are not limited to: wood, foam, and various types of honeycomb. Other core materials may also include, but are not limited to: web materials embedded in a thermosetting resin and fiber-reinforced polymer resin materials. The upper and lower skins may also comprise composite materials such as polymer resin materials including fiber reinforcing elements embedded therein. Exemplary polymer resin materials may include, but are not limited to: thermosetting resins, such as unsaturated polyesters, vinyl esters, polyurethanes, epoxies, phenolics, and mixtures thereof. The fiber reinforcing elements may include, but are not limited to: E-glass fibers, S-glass, carbon fibers, KEVLAR®, metal (e.g., metal nano-fibers), high modulus organic fibers (e.g., aromatic polyamides, polybenzamidazoles, and aromatic polyimides), and other organic fibers (e.g., polyethylene and nylon). Blends and hybrids of such materials may also be used as a reinforcing element. Other suitable composite materials that may be used as a reinforcing element within components of the first composite material may include, but are not limited to: whiskers and fibers constructed of boron, aluminum silicate, or basalt. Exemplary fiber reinforced panels that may be used as a composite floor member and methods of making such panels are disclosed in the following U.S. patents: U.S. Pat. Nos. 5,794,402; 6,023,806; 6,044,607; 6,108,998; 6,645,333; and 6,676,785, all of which are incorporated herein in their entirety. In addition, according to some embodiments of the composite cargo floor assembly 10 of the present invention, the floor member may also comprise a TRANSONITE® composite panel available from Martin Marietta Composites of Raleigh, N.C. According to some embodiments, the core of the sandwich panel used to form the floor member may be formed of a foam material with a plurality of fibers extending through the foam and connecting the two laminated skins secured to each opposing surface of the foam core. [0022] According to some embodiments of the composite cargo floor assembly 10 of the present invention, the cross members 21 , 22 of the support frame 20 may be formed of a second composite material that may include, but is not limited to: a pultruded tubing material; a pultruded and/or extruded composite tubing; a composite tubing material comprising a polyurethane matrix and a plurality of E-glass fibers disposed within the polyurethane matrix; and combinations thereof. According to various embodiments, the second composite material forming the cross members 21 , 22 may comprise a variety of different polymer resin materials including, but not limited to: thermosetting resins, such as unsaturated polyesters, vinyl esters, polyurethanes, epoxies, phenolics, and mixtures thereof. The fiber reinforcing elements of the second composite material forming the cross members 21 , 22 may also include, but are not limited to: E-glass fibers, S-glass, carbon fibers, KEVLAR®, metal (e.g., metal nano-fibers), high modulus organic fibers (e.g., aromatic polyamides, polybenzamidazoles, and aromatic polyimides), whiskers and fibers constructed of boron, aluminum silicate, or basalt, and other organic fibers (e.g., polyethylene and nylon). [0023] Some composite cargo floor assembly 10 embodiments of the present invention may further comprise an adhesive layer disposed between the mating surface 11 of the floor member and the support frame 20 for attaching the mating surface 11 to the support frame 20 to form the cargo floor assembly 10 . The adhesive layer may comprise one or more adhesive compounds that may include, but are not limited to: polyurethane adhesives and methacrylate adhesives. Furthermore, according to some embodiments, the various cross members 21 , 22 of the support frame 20 may also be operably engaged with the floor member 20 via various types of fasteners, including, but not limited to: screws, bolts, rivets, toggle fasteners, and combinations thereof. [0024] According to some embodiments, as shown generally in FIG. 1 , the first and second plurality of cross members 21 , 22 may intersect at substantially right angles and interconnect to form a ladder-shaped support frame 20 . According to other embodiments, the first and second plurality of cross members 21 , 22 may intersect at a selected angle (such as, for example 60 degrees) and interconnect to form a plurality of X-shaped, and/or V-shaped support frame 20 elements that may be operably engaged with the mating surface 11 of the floor member. Furthermore, as shown generally in FIGS. 1 and 2 , the support frame 20 may be interrupted along a portion of the mating surface 11 of the floor member define an open channel 30 corresponding to the position of an axle or a pair of axles attached to a vehicle with which the composite cargo floor assembly 10 embodiments of the present invention may be operably engaged. As one skilled in the art will appreciate, the open channel 30 defined by the various portions and/or segments of the support frame 20 may be wide enough to accommodate 2 or more axles and/or any number or pattern of axles that may be present on a vehicle to which the composite cargo floor assembly 10 is applied. [0025] The individual cross members of the first and second plurality of cross members 21 , 22 may have various cross-sectional shapes. For example, according to some embodiments of the present invention (as shown generally in FIGS. 1, 2 , and 4 ), the first and second plurality of cross members 21 , 22 may have a substantially rectangular cross-section. According to other embodiments, the first and second plurality of cross members 21 , 22 may also be configured to have a variety of different cross-sectional shapes that may include, but are not limited to: circular, oval, half-circle, polygons (having various numbers of sides), square, and combinations of the above-listed cross-sectional shapes. Furthermore, according to various embodiments of the present invention the first and second plurality of cross members 21 , 22 may be substantially hollow so as to decrease the amount and weight of material required to form the support frame 20 . Furthermore, as one skilled in the art will appreciate, the relative thicknesses of the material wall used to form the cross members may be optimized to provide an optimal strength-to-weight ratio. [0026] Furthermore, as shown generally in FIG. 2 , the first and second plurality of cross members 21 , 22 may also define a plurality of apertures 25 for receiving a corresponding plurality of fasteners for operably engaging the support frame 20 with a frame of a vehicle with which the composite cargo floor assembly 10 may be operably engaged. For example, as shown in FIG. 2 , the cross members 21 , 22 may define a plurality of circular apertures 25 for receiving fasteners that may include, but are not limited to: bolts, rivets, screws, toggle fasteners, and combinations thereof. The apertures 25 may be defined in portions of the cross members 21 , 22 corresponding substantially to corresponding apertures defined in a portion of a cargo vehicle frame such that the composite cargo floor assembly 10 of the present invention may be operably engaged with the cargo vehicle frame via the fasteners that may extend through the apertures 25 defined in the cross members 21 , 22 . In some embodiments, the apertures 25 defined by the cross members 21 , 22 may also be threaded so as to be capable of receiving a threaded fastener such as a bolt and/or screw for operably engaging at least one embodiment of the composite cargo floor assembly 10 of the present invention with a cargo vehicle frame which may include, but is not limited to: a flat bed truck frame, a trailer frame, a flat bed railcar, and/or another cargo vehicle frame. [0027] As shown generally in FIG. 3 the floor member of the composite cargo floor assembly 10 in some embodiments of the present invention may have a substantially rectangular shape corresponding to the approximate size and/or shape of a cargo vehicle frame with which the composite cargo floor assembly 10 is designed to be operably engaged. Furthermore, in some embodiments, the floor member may define at least one notch 15 at a corner thereof for receiving a corner post (not shown) adapted to extend substantially vertically from the load bearing surface 12 of the floor member. According to various embodiments, the notch 15 defined in the floor member may be formed to have a variety of different shapes corresponding substantially to a cross-sectional shape of a corner post to be received therein. For example, the notch 15 defined in at least one corner of the floor member may define shapes including, but not limited to: rectangular, circular, oval, polygonal, half-circular, quarter-circular, and/or combinations thereof. [0028] FIG. 4 shows another alternate embodiment of the composite cargo floor assembly 10 of the present invention, wherein the floor member comprises at least one bracket 17 . According to some embodiments, the bracket 17 may include a first member attached to the floor member and extending laterally from an edge of the load-bearing surface 12 thereof. In some embodiments, the bracket 17 may also include a second member extending generally upward at a selected angle from the first member of the bracket 17 for receiving a side wall (not shown). For example, the second member of the bracket 17 may extend substantially vertically from at least one edge of the floor member as to be capable of receiving a side wall (not shown) adapted to extend substantially vertically from the load bearing surface 12 of the floor member. In some such embodiments, the bracket 17 may allow the assembly 10 of the present invention to be combined with wall structures to form an enclosed cargo-carrying structure. In some embodiments, the at least one bracket 17 may be integrally formed with the floor member and may comprise one or more of the first and/or second composite materials, as described above. For example, some embodiments of the floor member of the present invention having one or more brackets 17 , as shown generally in FIG. 4 , may be integrally formed, using heat, pressure, adhesive materials, and/or other composite material processing steps that will be appreciated by one skilled in the art such that the floor member and bracket 17 may be provided in substantially one piece, such that few or no fasteners may be required to form the integral floor member and bracket 17 sub-assembly. According to some other embodiments of the present invention, the bracket 17 may be operably engaged with one or more edges of the floor member via one or more fastener devices and/or adhesives which may include, but are not limited to: screws, bolts, rivets, toggle fasteners, epoxy adhesives and/or combinations thereof. [0029] Many modifications and other embodiments of the inventions set forth herein will come to mind to one skilled in the art to which these inventions pertain having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is to be understood that the inventions are not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.
The invention provides a composite cargo floor structure for providing a load-bearing surface on a cargo vehicle frame. More specifically, the invention provides composite cargo floor structure including a floor member composed of a first composite material and a support frame attached to the floor member, wherein the structural elements of the support frame are composted of a second composite material. The resulting composite cargo floor structure thus provides a cargo floor having a durable load-bearing capacity, a substantial resistance to harsh environmental conditions, and a reduced weight.
1
TECHNICAL FIELD [0001] The present invention relates to a method of tensioning a wrap around a blood vessel, such as an arterial vessel, and an associated tensioning device. [0002] The invention has been primarily developed for use in securing an inflatable balloon or chamber of an implantable counter-pulsation heart assist device against the ascending aorta and will be described hereinafter with reference to this application. However, the invention also finds broader application in the tensioning of wraps around any blood vessel, whether static or dynamic, applied to either an artery or vein. BACKGROUND OF THE INVENTION [0003] The Applicant's International PCT Patent Application Nos. PCT/AU00/00654 and PCT/AU01/01187 disclose heart assist devices, systems and methods. More particularly, these specifications disclose vessel deformers in the form of inflatable balloon or chambers which form part of implantable counter-pulsation heart assist devices. The balloon or chambers are cyclically inflated and deflated and used to compress the patient's ascending aorta during diastole and release the compression during systole. [0004] The balloon or chamber are generally secured to the aorta by a wrap or sheath, which is secured around a section of the aorta with the balloon or chamber between the wrap and the vessel. For the heart assist device to function efficiently, it is necessary that the wrap be a snug fit around the aorta when the balloon or chamber is deflated. [0005] During the implantation of known heart assist devices, the wrap is pulled tight around the aorta and held by forceps or similar clamps whilst the regions of the wrap adjacent to the aorta are sutured together. It is difficult for a surgeon to judge exactly how tight the wrap is during this procedure. It is also difficult for repeatable tension to be applied to wraps or for the wrap to be conformal about the length of the wrap (i.e. for the tension to be evenly spread along the length of the wrap). [0006] It is also known to apply static wraps to the exterior of blood vessels, for instance to strengthen a vessel suffering from aneurysmal disease. It is also similarly difficult to appropriately adjust the tension of such static wraps when they are applied to the vessel to be reinforced. [0007] It is an object of the present invention to substantially overcome or at least ameliorate one or more of the above disadvantages. SUMMARY OF THE INVENTION [0008] Accordingly, in a first aspect, the present invention provides a method of securing a flexible wrap around a blood vessel, the wrap being generally elongate and having first and second end portions, the method including the steps of: [0009] (1) wrapping the flexible wrap around the blood vessel; [0010] (2) passing the first end portion of the wrap through a buckle device affixed substantially distally from the first end portion of the wrap; [0011] (3) adjusting the tension in the wrap to a desired level by movement of the first end portion of the wrap relative to the buckle device; [0012] (4) securing together adjacent parts of the wrap substantially adjacent the blood vessel; and [0013] (5) removing the buckle device. [0014] The buckle device preferably includes means to hold the adjacent parts of the wrap together. [0015] The wrap preferably holds a heart assist device vessel deformer in place, most preferably against an arterial vessel. [0016] Step 4 preferably involves securing by suturing or stapling—sutures may be or known materials such as non-absorbable sutures e.g. Prolene™ or silk, or nitinol sutures or staples, or absorbable sutures such as cat-gut or Vicryl™. [0017] The method preferably also includes the step of trimming off the parts of the wrap external to the sutures. [0018] The method preferably also includes the step of releasably attaching the buckle device to the wrap prior to Step 1 . In one form, the buckle device is sutured to the second end portion of the wrap. In another form, the buckle device includes a leg or legs that respectively pierces or pierce the wrap. In another form, the buckle device includes a pair of spring legs that are adapted to clamp the wrap therebetween. These latter buckle systems are “self-holding”. [0019] In one embodiment, the buckle device preferably includes at least two parallel and spaced apart legs and the method preferably includes adjusting the tension in the wrap until the legs begin to deform towards each other. [0020] In another embodiment, the wrap includes aortic circumference distance markers, and the method preferably includes adjusting the tension in the wrap until the desired aortic circumference is reached. [0021] In still another embodiment, the buckle is adapted to lightly grip the first and second end portions of the wrap so that the wrap may be drawn tight around the vessel and then released. In this embodiment of the invention the buckle may be attached the second end portion of the wrap. More preferably, the buckle is adapted to allow the wrap to begin to pull through the buckle when the tension applied to the wrap to the vessel just equals the holding force of the buckle on the wrap—this allows a relatively repeatable tension to be applied to the wrap. [0022] The present invention further consists in a flexible wrap adapted to be secured around a blood vessel within a patient, the wrap being generally elongate and having first and second end portions, there being attached to the wrap a buckle device through which the second end portion of the wrap may be threaded to allow the wrap to be drawn to a desired tension about the blood vessel, the buckle device being removable from the wrap after the end portions thereof have been connected together around the blood vessel. [0023] The buckle device preferably includes means to hold overlapping parts of the wrap together. [0024] The buckle device is preferably attached to the wrap substantially distally to the second end portion. The buckle device is preferably attached to the wrap adjacent to the first end portion. [0025] The end portions are preferably sutured together. [0026] In another aspect, the present invention provides a heart assist device wrap for use in securing a vessel deformer to an arterial vessel, the wrap being generally elongate with two end portions and having a buckle device releasably attached thereto that includes at least a pair of substantially parallel legs with a gap therebetween through which the two end portions of the wrap can pass. [0027] In a further aspect, the present invention provides a buckle device for use in securing a wrap around an arterial vessel, the wrap being generally elongate and having two end portions, the buckle device including at least a pair of substantially parallel legs with a gap therebetween through which the two end portions of the wrap can pass, wherein at least one of the legs is adapted for releasably fixing to the wrap. [0028] In one form, the buckle device is adapted for suturing to the wrap. In this form the buckle has loops through which the buckle device is attached to one end of the wrap so that the other end of the wrap can be pulled without the buckle moving relative to the first end. [0029] In another form, the buckle device is adapted for stapling to the wrap. [0030] In a further form, the device includes a pair of enlarged ends adapted to clear suture knots during removal of the device from the secured wrap. The device may also include an enlarged formation in about the middle of one the legs, which is adapted to allow forcep access between the two legs to facilitate grasping of the second end of the wrap to draw the wrap end through the buckle. The other leg of the device is preferably formed from two part legs stemming from each of the enlarged end formations, the two part legs having a small clearance between their distal ends. The clearance is adapted to facilitate removal of the buckle from any sutures that are used to secure the wrap yet are still continuous to the wrap at the time of buckle removal. [0031] It is desirable to have the buckle device hold itself in position whilst the wrap is secured to itself, as opposed to requiring the use of surgical clamps or the like. The is buckle device may include a third leg that pierces the wrap. In this form, the three legs of the buckle device are all substantially parallel, with the first and second legs being joined at one end of the wrap and the other end of the wrap is passed between the second and third legs and adjusted to the desired wrap tension. The second and third legs act to compress and hold the wrap in position. Alternatively, small barbs can be placed on one of the legs, such that as the wrap end is pulled through, the material runs forward over the barb, and on pulling back, the barbs snag into the wrap to secure it in position whilst the wrap is secured. [0032] A further form of the invention utilises spring wire and telltales to indicate the tension developed when pulling on the wrap to secure it around the blood vessel. The arms of the buckle are formed and sized relative to spring force such that when the wrap is appropriately tensioned the arms deflect towards one another. A further feature can be added to indicate the degree of tension by the use of over-lapping perpendicular arms to the flexure. [0033] In another approach, the buckle is adapted to prevent accidental removal during its use. In one form, loops in one side of the parallel legs are provided to secure the buckle to the wrap. The loops provide secure attachment of the buckle by preventing migration of the buckle from its attaching sutures. The loops can be replaced by bends such a V or U, alternatively a tubular shape can be fit and secured to the legs to perform the same function. [0034] In a further alternative the buckle is curved to replicate the adjacent curve of a blood vessel, such as an aorta. BRIEF DESCRIPTION OF THE DRAWINGS [0035] Preferred embodiments the invention will now be described, by way of examples only, with reference to the accompanying drawings in which: [0036] FIG. 1 is a perspective view of a first embodiment of a buckle device according to the invention; [0037] FIGS. 2 to 4 sequentially show a heart assist device being secured to an arterial vessel using the buckle device shown in FIG. 1 ; [0038] FIG. 5 is a plan view of the second embodiment of buckle device according to the invention; [0039] FIGS. 6 to 9 sequentially show a heart assist device being secured to an aorta using the buckle device shown in FIG. 5 ; [0040] FIG. 10 is a perspective view of a third embodiment of a buckle device according is to the invention; [0041] FIG. 11 show a wrap secured to around an invisible arterial vessel using the buckle device shown in FIG. 10 ; and [0042] FIGS. 12 to 15 are plan views of fourth to seventh embodiments of buckle devices according to the invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT [0043] FIG. 1 shows a first embodiment of a buckle device 10 according to the invention. The device 10 is formed from stainless steel wire of approximately 1 mm in diameter. Depending on application, the wire diameter can vary from 0.1-1.5 mm, and could alternatively be molded from plastic. [0044] The device 10 includes a first leg 12 and a second leg 14 . The legs 12 , 14 are substantially parallel and spaced apart by a gap 16 . The device 10 has bulbous ends 18 and 20 and a bulbous formation 24 in the middle of the leg 12 , the purposes of which will be described below. The second leg 14 is formed from two leg parts 14 a and 14 b which have a small clearance 14 c between their distal ends, the purpose of which will also be described in more detail below. [0045] FIG. 2 shows a heart assist device 26 being secured to a section of aorta 28 (shown in phantom lines) by a substantially inelastic flexible wrap 30 , which is preferably made from polyester or similar plastics material. The wrap 30 may be made from a sheet of woven material such as that sold under the trade mark Dacron or may be made from a sheet of a film like material such as that sold under the trade mark GoreTex. The wrap 30 is longitudinal in shape and has first and second ends 30 a , 30 b. [0046] Prior to the operation to implant the heart assist device 26 , the buckle device 10 is attached to the wrap 30 , near the end 30 a , by sutures 32 . Put another way, the buckle device 10 is attached to the wrap 30 remote or distal from the end 30 b. [0047] The heart assist device 26 is then positioned on the exterior of the aorta 28 and the wrap 30 is placed over the heart assist device 26 and around the aorta 28 . The end 30 b of the wrap 30 is then pulled through the gap 16 into the position shown in FIG. 2 . The bulbous formation 24 in the leg 14 , 12 provides convenient access for forceps to reach between the two legs 14 , 16 and grasp the end 30 b of the wrap 30 to pull it through the gap 16 . [0048] The surgeon then grasps the two ends 30 a , 30 b of the wrap 30 and pulls them in substantially opposite directions until the legs 12 , 14 of the buckle device 10 begin to resiliently deform. This initial deformation provides the surgeon with a repeatable indication of the preferred level of tension in the wrap 30 . The ends 30 a , 30 b of the wrap 30 are then maintained at this preferred position and tension whilst they are joined together with sutures 34 , as shown in FIG. 3 . [0049] To complete the implantation, the parts of the wrap 30 external to the sutures 34 are cut off, as shown in FIG. 4 . The sutures 32 securing the buckle device 10 to the wrap 30 are then cut so the buckle device 10 can be slid over the sutures 34 and removed. The bulbous ends 18 , 20 of the buckle device 10 provide clearance for any knots of the sutures 34 that may be encountered during the removal of the buckle device 10 . The clearance 14 c also facilitates removal of the buckle 10 from any sutures that are used to secure the wrap 30 yet are still continuous to the wrap 30 at the time of buckle removal. [0050] FIG. 5 shows a second embodiment of the buckle device 50 according to the invention. The device 50 will now be described with reference to FIGS. 6 to 9 and like reference numerals to those shown in relation to the first embodiment will be used to indicate like features in the second embodiment. [0051] The buckle device 50 is also made from stainless steel wire and is formed from four legs 52 , 54 , 56 and 58 . The two legs 52 and 54 are folded back closely against one another so that they grip the wrap 30 when it is forced therebetween. The legs 54 , 56 and 58 are all equally spaced apart with gaps 60 and 62 therebetween. [0052] The buckle device 50 is attached to end 30 a of the wrap 30 prior to commencement of the surgical procedure. This attachment is achieved by inserting the leg 52 through two holes 64 and 66 in the wrap 30 , as shown in FIG. 6 . Threading the leg 52 through the wrap 30 in this way, in combination with the wrap also being clamped between the two legs 52 , 54 , ensures a secure attachment. The wrap 30 is then positioned around the aorta as shown in FIG. 6 with the other end 30 b threaded through the gaps 60 and 62 . Forceps 66 are then used to pull the other end 30 b of the wrap 30 through the gaps 60 , 62 , as shown in FIG. 7 . [0053] As is shown in FIG. 8 , the forceps 66 are then used to move the end 30 b of the wrap 30 relative to the buckle device 50 in order to tension same. The wrap 30 is tensioned until the leg 58 begins to resiliently deform, which again provides a repeatable indication of wrap tension to the surgeon. The two ends 30 a , 30 b of the wrap 30 are then sutured together by sutures 34 . When the suturing has been completed, the buckle device 50 is removed by sliding it away from the wrap 30 in the direction of arrow 68 . The parts of the wrap 30 external the sutures 34 can then be trimmed off. [0054] FIGS. 10 and 11 show a third embodiment of buckle device 70 according to the invention. Like reference numerals to those used in relation to the first embodiment will be used to indicate like features in the third embodiment. The device 70 is similar to the first embodiment except it also includes small angled hooks or barbs 72 , which provide a self holding or non return function to maintain the ends of the wrap 30 a , 30 b in their preferred position during their suturing together. [0055] FIGS. 12 to 15 respectively show fourth to seventh embodiments of buckle device 80 a , 80 b , 80 c , and 80 d , according to the invention. Like reference numerals to those used in relation to the first embodiment will be used to indicate like features in these embodiments. The devices 80 a , 80 b , 80 c , and 80 d all include looped portions 82 through which tacking sutures may be threaded to hold the buckle in place on the wrap. [0056] The main advantage of the devices and methods disclosed above is that they provide a consistent and repeatable indication of wrap tension to the surgeon, which enables the ends of the wrap to be accurately positioned prior to their connection by suturing. [0057] Another advantage is that the buckle device acts as a guide to suturing of the wrap to itself. The suture needle can be skimmed just above the buckle and thus the buckle acts to reduce the risk of the suture needle or staple etc to inadvertently puncture the underlying inflatable balloon. [0058] It will be appreciated by persons skilled in the art that numerous variations and/or modifications can be made to the invention as shown in the specific embodiments without departing from the spirit or scope of the invention as broadly defined. [0059] For example, the buckle devices could alternatively be made of plastic. Additionally, absorbable suture material may be used if the heart assist device is only required for a finite period (eg. two to three weeks or up to 6 months, depending on the suture material used), which would also then allow percutaneous removal. If desired the wrap may be attached to the heart assist device before placement into the patient's body.
A method of securing a flexible wrap ( 30 ) around a blood vessel ( 28 ). The wrap ( 30 ) being generally elongate and having first ( 30 a ) and second ( 30 b ) end portions. The method including the steps of 1. wrapping the flexible wrap around the blood vessel ( 28 ); 2. passing the first end ( 30 a ) of the wrap ( 30 ) through a buckle device ( 10 ) affixed substantially distally from the first end ( 30 a ) of the wrap ( 30 ); 3. adjusting the tension in the wrap ( 30 ) to a desired level by movement of the first end ( 30 a ) of the wrap ( 30 ) relative to the buckle device ( 10 ); 4. securing together adjacent parts of the wrap ( 30 ) substantially adjacent the blood vessel ( 28 ); and 5. removing the buckle device ( 10 ).
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BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an authoring system for computerized messages such as electronic mail, and specifically to an authoring system for computerized messages that can create messages containing recipient-specific content such that all recipients do not receive the identical version of the message. 2. Description of the Related Art Current computerized messaging systems provide for the ability to send a computerized message to more than one recipient. Such systems are limited, however, in that each recipient receives the identical message. This is inconvenient, for example, in a situation where it is desired to send a private comment to some but not all of the recipients. For example, in an electronic mail (“E-mail”) messaging system, the sender authors a text message, with or without attachments, that can be sent to recipients in any of three categories: a “To:” category, a “cc:” category, and a “bcc:” category. As is known, the “To:” category is for the directly-intended recipient or recipients, the “cc:” category is for courtesy-copy recipients who are included for information, and the “bcc:” category is for blind-courtesy-copy recipients who are intended to receive the message without other recipients being aware of their receipt. However, even with the above addressing categories, what is received by each recipient is the entire text of the message and all attachments. Thus, each recipient receives the identical message. In some situations, the sender wishes to forward some portions of a message only to certain recipients and not to others. For example, a sender may desire to include private comments in the E-mail message, with the private comments being readable only by bcc recipients. However, since current E-mail systems send the identical message to each and every recipient, it is necessary for the sender to create two different E-mail messages, and to select which message is to be sent to which recipient. This arrangement is cumbersome and time-consuming, and inevitably leads to errors. SUMMARY OF THE INVENTION It is an object of the invention to address the foregoing difficulties in conventional computerized messaging systems by providing an authoring system for computerized messages, such as electronic mail, that contains recipient-specific content. In one aspect, the invention provides for a sender of computerized messages such as E-mail to select portions of the message or attachments which are sent only to certain recipients. In one embodiment, authoring of an E-mail message in which selected portions of the text or attachments are sent only to certain recipients involves the steps of first creating a message and creating a list of recipients. If no contrary instructions are entered, the entire message will be sent to all recipients. After the author has created the list of recipients, any portion or portions of the message which are to be sent only to certain recipients are selected, such as with a pointing device or with key strokes. A list of available recipients is provided to the sender for selection, such as with a “pop-up” menu. The recipients for the selected text are then selected (or selected ones can be deselected, if desired). Any other portions to be sent only to some recipients are also selected in the same way, and the respective lists of recipients for those portions are designated, resulting in a message in which one or more portions are not sent to all recipients. As an alternative approach, the author can identify which portions of the message are for which recipients in a different manner. At the beginning of the message, the author can select or list the intended recipient(s) for the initial portion of the message, and then compose that portion. The author then selects which recipients are to receive the following portion, and then composes that following portion. This procedure is continued until the message is complete. Thus, according to this aspect of the invention, authoring a computerized message that contains recipient-specific content involves composing plural portions of the message, identifying one or more recipients to which at least one portion of the message will be sent, and for each recipient associating at least one portion of the message such that at least one recipient does not receive all portions of the message. This associating may comprise selection of portions and identifying recipients of selected portions, and identification may be by either selection or deselection from the list of recipients. Thereafter, the message may be sent with each recipient receiving only its designated portion or portions of the message. Other aspects of the invention involve the provision of a pleasing and efficient visual interface between the authoring system and the sender. For example, recipients for the selected portions of the message may appear colored, underlined or otherwise highlighted when the portions of the message that are received by such recipients has received focus by the sender. The portions of the message itself may also appear colored, underlined or otherwise highlighted, even when not in focus, so as to indicate that the highlighted portion has a limited list of recipients. Color coding or some other form of differential highlighting (such as multiple underlining) may also be employed so as to show which different portions of a message are sent to different sets of recipients. In further aspects, the invention allows the sender to view the respective portions that are actually sent to each recipient. Viewing may be by color coding or differential highlighting as described above. Alternatively, the portions can be viewed in an “as-received” mode such that the sender can view the message as it will be received by each recipient. Thus, the invention allows the sender to view the message with visual cues of the portions that are sent to each recipient. Conversely, rather than viewing the message, the sender can view recipients, such as by viewing a list of recipients for each selected portion of a message. This aspect of the invention provides the sender with the ability to modify the list of recipients for each portion, and to make such modifications easily. At the receiving end of the message, a recipient can view received messages with portions highlighted or a recipient list displayed, so that the recipient of private portions of the message can know that one or more others did not receive that portion, and can further know which recipients actually received the private portion. This brief summary has been provided so that the nature of the invention may be understood quickly. A more complete understanding of the invention can be obtained by reference to the following detailed description of the preferred embodiment thereof in connection with the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a representational view of a computerized messaging system in which the present invention may be utilized. FIG. 2 is a representational view of a computer system that can serve as an E-mail client or an E-mail server for use with the present invention. FIG. 3 is a detailed block diagram showing the internal architecture of the computer system shown in FIG. 2 . FIG. 4 is a representational view showing E-mail applications and E-mail files stored in a fixed disk of a computer system that serves as an E-mail client. FIG. 5 is a representational view showing E-mail applications and E-mail files stored in a fixed disk of a computer system that serves as an E-mail server. FIG. 6 is a representational view of a graphical user interface for an E-mail editor according to the preferred embodiment of the invention. FIG. 7 is a view for illustrating how a user can manipulate the interface of FIG. 6 in order to view a message so as to see how the message will appear as received by each recipient. FIG. 8 is a representational view of a graphical user interface for an E-mail reader according to the preferred embodiment of the invention. FIG. 9 is a representational view illustrating how the interface of FIG. 8 can be manipulated so as to provide a recipient of a message with a view of the message as it is received by other recipients. FIG. 10 is a flowchart for explaining the operation of the preferred embodiment of the invention in authoring computerized messages. FIG. 11 is a flowchart for describing the operation of an E-mail editor in carrying out the authoring of computerized messages according to the preferred embodiment of the invention. FIG. 12 is a flowchart for describing viewing of a message according to the preferred embodiment of the invention. FIG. 13 is a flowchart for describing the operation of an E-mail reader in performing the viewing of computerized messages according to the preferred embodiment of the invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a representational view of computerized messaging system 1 , in this case an electronic mail system, in which the present invention can be utilized. Computer systems 2 through 6 are connected to each other through network 7 . Computer systems 2 through 5 are E-mail clients, and computer system 6 is an E-mail server. Computer systems 2 through 6 can comprise programmable general-purpose computers or other types of data processing equipment. Network 7 can comprise a local area network (LAN) such as an Etherneto network, a wide area network (WAN) such as a pair of LANs connected over a phone line via routers, a commercial E-mail network, the Internet, an intranet, or any other network that accommodates computer messaging services such as E-mail. In operation, a user generates an E-mail message using one of the E-mail clients, for example, E-mail client 2 . The user then sends the E-mail message to recipients who have access to the E-mail clients of computerized messaging system 1 . When the user sends the E-mail message, the message is communicated to E-mail server 6 . Typically, E-mail server 6 maintains a shared directory with subdirectories corresponding respectively to each of the users who have access to computerized messaging system 1 . A copy of the message is stored in the subdirectories corresponding to the intended recipients. Whenever a user is logged-on to one of E-mail clients 2 through 5 , that E-mail client periodically polls E-mail server 6 to see if any unread messages have been stored in the subdirectory corresponding to that user. In the example described above, if the user is an intended recipient of the E-mail message, the server notifies the client that a new unread message has been placed in that user's subdirectory on the server. Then, the user can read the message using the E-mail client to which the user is logged-on, and the user can store the message for later reference. After the message is read by the user, the message typically is deleted from that user's subdirectory on E-mail server 6 so as to free-up space on the server. It should be noted that the invention also is applicable to E-mail systems that differ from computerized messaging system 1 described above. For example, in other E-mail systems, a single computer system can serve as both an E-mail client and an E-mail server. The invention is applicable to E-mail systems that have any number of E-mail clients and E-mail servers, and that are interconnected through any number of networks. The invention also is applicable to other types of computerized messaging systems, such as instant message systems (e.g., WinPop®), chat rooms, and the like. FIG. 2 is a representational view of a computer system 10 that can serve as an E-mail client or an E-mail server for use with the present invention. Computer system 10 may be a Macintosh®, PC-compatible, or other type of system having an operating system which preferably is a windowing operating system, such as Microsoft® Windows, but which may also be a non-windowing system, such as DOS or UNIX. In the preferred embodiment, computer system 10 is a Pentium®-based computer system. Provided with computer system 10 are display 11 , which may be a color monitor, keyboard 12 for entering user commands, and pointing device 14 such as a mouse for pointing to and for manipulating graphical user interfaces and other objects displayed on display 11 . Computer system 10 also includes a mass storage device such as fixed disk 15 for storing computer-executable process steps for E-mail applications, E-mail files, other applications, other files, and the like. Such storage may also be provided by a CD-ROM (not shown). Network interface 17 provides an interface between computer system 10 and network 7 , as described with respect to FIG. 1 above. Thus, network interface 17 provides computer system 10 with access to computerized messaging system 1 . FIG. 3 is a detailed block diagram showing the internal architecture of computer system 10 . As shown in FIG. 3, computer system 10 includes central processing unit (CPU) 19 , which interfaces with computer bus 20 . Also interfacing with computer bus 20 are fixed disk 15 , network interface 17 , main memory (RAM) 21 , read-only memory (ROM) 22 , floppy disk interface 24 , display interface 25 to display 11 , keyboard interface 27 to keyboard 12 , and mouse interface 28 to pointing device 14 . Other components, such as a printer, scanner, modem or the like, also can be interfaced to computer bus 20 . Main memory 21 interfaces with computer bus 20 so as to provide RAM storage to CPU 19 during execution of software applications. More specifically, CPU 19 loads process steps from fixed disk 15 , another storage device, or some other source such as network 7 , into main memory 21 . CPU 19 then executes the stored process steps from main memory 21 in order to execute applications. Data such as E-mail messages can be stored in fixed disk 15 , main memory 21 , or at some other location in network 7 , where the data can be accessed by CPU 19 during execution of the process steps. As also shown in FIG. 3, fixed disk 15 typically contains an operating system, E-mail applications, E-mail files, other applications, other files, and the like. In the preferred embodiment, the E-mail applications and E-mail files stored on fixed disk 15 differ depending on whether computer system 10 is serving as an E-mail client or as an E-mail server. FIGS. 4 and 5 illustrate the E-mail applications and E-mail files stored in fixed disk 15 in these two cases. FIG. 4 is a representational view showing E-mail applications and E-mail files stored in fixed disk 15 in a case where computer system 10 is serving as an E-mail client. As shown in FIG. 4, the E-mail applications stored in fixed disk 15 include E-mail editor 31 and E-mail reader 32 . E-mail editor 31 is used for generating, editing, and sending E-mail messages to one or more recipient(s) who can access computerized messaging system 1 . E-mail reader 32 is used for reading E-mail messages sent to a user logged-on to computer system 10 . In the E-mail client context, fixed disk 15 also stores E-mail files including temporary files generated by E-mail editor 31 and by E-mail reader 32 . FIG. 5 is a representational view showing E-mail applications and E-mail files stored in fixed disk 15 in a case where computer system 10 is serving as an E-mail server. As shown in FIG. 5, the E-mail applications stored in fixed disk 15 include E-mail server 35 . E-mail server 35 manages E-mail files stored in fixed disk 15 , including unread mail 36 , read mail 37 , and sent mail 38 . Unread mail 36 includes E-mail messages stored in a shared directory before those messages have been read by their intended recipients, as described above with respect to FIG. 1 . Read mail 37 includes E-mail messages that have been read by users and that users have decided to retain for later reference. Sent mail 38 includes E-mail messages that have been sent by a user using E-mail editor 31 on an E-mail client and that the user also has retained for later reference. Preferably included with the E-mail files are logs 39 that track E-mail usage. Of course, other arrangements of E-mail files are possible. FIG. 6 is a representational view of a graphical user interface for E-mail editor 31 according to the preferred embodiment of the invention. This graphical user interface comprises E-mail editor window 41 . Included in E-mail editor window 41 are pull-down menu bar 42 , tool bar 43 , and message area 44 . As shown in FIG. 6, pull-down menu bar 42 includes pull-down menus for file commands, edit commands, view commands, format commands, tool commands, and help commands. Other pull-down menus also can be provided in pull-down menu bar 42 . Tool bar 43 includes tools for determining font type, font size, and format information for a message generated using E-mail editor window 41 . Tool bar 43 also includes send buttons 45 for sending, forwarding, and replying to messages, and attachment button 46 for attaching files to a message. Message area 44 includes “To:” list box 47 , “cc:” list box 48 , “bcc:” list box 49 , “Subject:” list box 50 , and message text area 51 . “To:” list box 47 is used for designating intended recipients of a message entered into message text area 51 . “Cc:” list box 48 is used for designating or courtesy copy recipients of the message. “Bcc:” list box 49 is used for designating blind-courtesy-copy recipients of the message. Blind-courtesy-copy recipients are recipients who are intended to receive the message without other recipients being aware of their receipt. “Subject:” list box 50 is used for entering an optional subject title for the message. Message area 51 is used for entering the text body of the message. Icons representing attachments also can appear in message text area 51 . In order to generate a message, a user manipulates items in E-mail editor window 41 using cursor 53 controlled with pointing device 14 . The user identifies intended recipients of the message in list boxes 47 through 49 , enters a subject for the message in “Subject:” list box 50 , and enters text for the body of the message in message text area 51 . Attachments can be designated using a window called up with attachment button 46 . As the message is being entered, the user can “focus” on a part of the message by pointing to that part of the message with cursor 53 and then clicking on a left button of pointing device 14 . When the user clicks the left button of pointing device 14 , focus indicator 54 appears where cursor 53 is positioned. If the user keeps the left button depressed and moves cursor 53 , focus indicator 54 follows the cursor, and any text through which focus indicator 54 passes is highlighted. This highlighted text is “selected”. In FIG. 6, text line 56 of message text area 51 has been so selected, as indicated by the broken line surrounding text line 56 . On an actual display, the selected text preferably is highlighted, as for example by being displayed in a rectangle with inverse colors as compared to unselected text. Selected text is affected by various commands entered into E-mail editor window 41 . For example, if the user selects a portion of text in message text area 51 and then activates one of the format tools in tool bar 43 , the formatting command (e.g., bold or underline) is applied to the selected text. In conventional systems, a user can utilize an E-mail editor to generate and format a message in a similar fashion as described above. The user can designate “To:” category recipients, “cc:” category go recipients, and “bcc:” category recipients. However, in these conventional systems, each recipient receives identical message text and attachments. Thus, if the user desires to direct special comments to some but not to others of the recipients, the user must create a separate message. As some of the contents of the separate message often will be the same as in the first message, this process is inefficient. The present invention addresses the foregoing deficiencies of conventional systems by allowing a user to author an E-mail message in which selected portions of text or attachments are sent only to certain recipients. In order to author such a message, the user first composes all or part of a message. In the absence of contrary instructions entered by the author (i.e., as a default procedure), the entire message will be sent to all recipients designated in list boxes 47 through 49 . Then, the user selects a portion of the message, such as text line 56 , and activates a recipient selection process, for example with key strokes or by clicking the right button of pointing device 14 . In response to this activation, a list of intended recipients is displayed, and the user can select or deselect recipients for the selected part of the message using the list. By selecting less than all of the listed recipients for portions of the message, the user easily can customize the message for different recipients. In the preferred embodiment, the list of recipients comprises a pop-up window such as pop-up window 59 shown in FIG. 6 . Pop-up window 59 includes several sections that allow different methods for selecting and/or deselecting intended recipients. Select/deselect-all section 61 allows the user to select or deselect all of the recipients at once. Individual selection section 62 allows the user to select or deselect recipients individually. As shown in FIG. 6, “Team Member 1 ”, “Manager”, and “President” have been selected as recipients for selected text line 56 . This designation of recipients is indicated by check marks next to the recipients in individual selection section 62 . Also included in pop-up window 59 are category selection section 63 and sent mail selection section 64 . Category selection section 63 allows the user to select intended recipients grouped by the recipient categories. Sent mail section 64 is provided to allow the user to designate portions of the message that should be included in the user's retained store of sent mail. For example, if the only recipient of a selected part of the message is “sent mail”, that portion of the message could be used for private notes that the user wants to retain concerning the message, but that the user does not want to be sent to any recipient. In order to select or deselect recipients, the user preferably points to a recipient using cursor 53 , and then selects or deselects that recipient by clicking on the left button of pointing device 14 . In the preferred embodiment, changes in any one of the sections are reflected in the other sections. For example, if the “To:” category in category selection section 63 is selected, the corresponding individual recipients in individual selection section 62 have check marks automatically displayed next to them, indicating that they have been selected. Optionally, if some but not all of the recipients for a category have been designated as recipients of the selected part of the message, a special mark (for example, a gray, rather than black, check mark) can be displayed next to that category. In addition, visual cues in message text area 51 and list boxes 47 through 49 preferably are provided to indicate which portions of the message are designated for which recipient. For example, text line 65 has been designated with a double underline, and recipients “Manager” and “President” in list boxes 48 and 49 , respectively, also have been highlighted with a double underline. This highlighting indicates that text line 65 is intended only for recipients “Manager” and “President”. In the preferred embodiment, highlighting such as by color-coding also is used to indicate portions of the message intended for different categories of recipients. For example, black text in message text area 51 is intended for all recipients, blue text is intended for “To:” recipients, green text is intended for “cc:” recipients, and red text is intended for “bcc:” recipients. In addition, recipients for text that is in focus can be color-coded or otherwise highlighted in list boxes 47 through 49 . Other types of highlighting and other color schemes can be used to provide the foregoing visual cues, and are included within the scope of the invention. These other types of highlighting include, for example, different fonts, different text styles (e.g., bold, shadow, etc.), flashing text, etc. After the user has designated the recipients for the various portions of the message, the user can continue adding text and attachments, redesignating recipients, etc., until the user is satisfied. In an alternative embodiment, recipients are associated with text by first selecting intended recipients. This selection can be made in a similar fashion as described above. Then, subsequently-entered text is automatically designated as intended for the selected recipients. If the user subsequently selects a different recipient or recipients, text entered following that designation is associated with those recipients. This process is repeated until the message is complete. In addition, the user can select already-entered text and modify the recipients of that text, as described above. At some point in the process of authoring the message, the user may desire to see how the message will appear as received by each recipient. Optionally, E-mail editor 31 is implemented so as to allow a user to view the message in this manner, as explained with reference to FIG. 7 below. In the preferred embodiment illustrated in FIG. 7, in order to view a message as it will be received by a particular recipient, the user clicks on view pull-down menu 66 from pull-down menu bar 42 of E-mail editor window 41 . Preferably, view pulldown menu 66 includes at least tool bars line 67 and as-received line 68 . Other lines can be provided in view pull-down menu 66 . Tool bars line 67 provides access to conventional tool bars. As-received line 68 provides access to list 69 of intended recipients. Shown in list 69 are individual selection section 71 , category selection section 72 , and sent-mail selection section 73 . Individual selection section 71 includes all recipients named in list boxes 47 through 49 . Category selection section 72 includes lines for the “To:” category, the “cc:” category, and the “bcc:” category. Sent-mail selection section 73 includes a line for selecting sent mail. In order to view the message as received by one of these recipients, the user clicks on the recipient using cursor 53 . For example, as shown in FIG. 7, Team Member 2 has been clicked on, as indicated by the check mark next to the line for Team Member 2 in individual selection section 71 . As a result, message text area 51 displays the message as it will be received by Team Member 2 . In particular, in the case that the message is the one shown in FIG. 6, text line 56 and text line 65 are omitted from the message, because Team Member 2 is not a selected recipient for these two lines of the message. Attachments can be added to the message using attachment button 46 in tool bar 43 . The recipients for an attachment can be designated in a similar manner as for portions of text. Once the user is satisfied with the contents of the message, including text and any attachments, and with the designation of recipients for portions of the text and the attachments, the user can utilize send buttons 45 to send the message to the recipients. A recipient can read the message using a conventional E-mail reader. However, in the preferred embodiment, the E-mail reader allows a recipient to identify which parts of the message he or she received that were not sent to all other recipients. FIG. 8 is a representational view of a graphical user interface for E-mail reader 32 according to the preferred embodiment of the invention. This graphical user interface comprises E-mail reader window 75 . Included in E-mail reader window 75 are pull-down menu bar 76 , tool bar 77 , and message area 78 . Message area 78 includes message information area 81 and message text area 82 . As shown in FIG. 8, message information area 81 indicates that the message is sent from “Project Leader” on “Date” to “Team Member 1 ”, “Team Member 2 ”, “Team Member 3 ”, and “Manager”. The “cc:” recipient line is placed above the “To:” recipient line because, in this example, the E-mail reader is being used by “Manager” (a “cc:” recipient). Message information area 81 also indicates that the subject of the message is “Project Status”. Message text area 82 includes message text corresponding to the message depicted in FIG. 6, including portions of text intended for recipient “Manager”. If a message includes any attachments, an icon linking the message to the attachment(s) preferably is shown in message text area 82 . Text lines 85 and 86 are highlighted, in the illustrated embodiment by underlining, to indicate that these text lines were not received by all the recipients listed in message information area 81 . It should be noted that text designated for recipient “President” in FIG. 6 is not shown in FIG. 8, because this text was not intended for receipt by “Manager”. If the user, in this case “Manager”, desires to see who else received the highlighted text, “Manager” places the text in focus and then calls up a list of the recipients for that text. For example, the user can position cursor 53 on the highlighted text and can left-click with pointing device 14 to call up focus indicator 54 . The user can then right-click with pointing device 14 to call up a list of recipients. In the preferred embodiment, the list is in a pop-up window such as pop-window 88 . The pop-up window includes individual section 89 and category section 90 . A check mark appears beside the recipients and the categories who have received the text in focus. Again, gray check marks (or other special indicators) optionally can be used to indicate that part but not all of a category has been designated as an intended recipient. Alternatively, the pop-up window can contain only those recipients who receive the text that is in focus. For example, in FIG. 8, such a pop-up window would include only “Manager”. The recipient of the message also may desire to view the message as it is received by other recipients (i.e., those who received less of the whole message than did the recipient in question). Of course, when the message is viewed in the as-received mode, only those parts of the message received by both the user and the identified recipient(s) are displayed. For example, if Manager viewed the message as received by President, Manager would not see text designated for President but not for Manager. Instead, Manager would see only those parts of the message that were intended for both Manager and President. FIG. 9 is a representational view illustrating how the preferred embodiment of E-mail reader window 75 can be manipulated to display a message as received by a particular recipient or category of recipients. The operation of E-mail reader window 75 in this respect is similar to the operation of E-mail editor window 41 shown in FIG. 7 . Briefly, the user accesses view pull-down menu 93 in pull-menu bar 76 . View pull-down menu 93 preferably includes at least tool bars line 94 and as-received line 95 . Other lines can be provided in view pull-down menu 93 . Tool bars line 94 provides access to conventional tool bars. As-received line 93 provides access to list 96 of the intended recipients. Shown in list 96 are individual section 98 and category section 99 . In order to view the message as received by one of these recipients, the user clicks on the recipient using cursor 53 . In operation, to create a message with recipient-specific content, a user composes the message, identifies one or more recipients to whom at least one portion of the message will be sent, and for each recipient associates at least one portion of the message such that at least one recipient does not receive all portions of the message. Preferably, the user can view a list of recipients of each portion and can view the message as it will be received by a particular recipient or recipients. Once the user is satisfied with the message, the author instructs the message to be sent, and the appropriate portions are sent to the appropriate respective recipients. The recipient can view the received message with portions highlighted such that the recipient of a message (or at least part thereof) is provided with visual cues as to whether other recipients have received the highlighted portions. The recipient can view portions of the message that are actually sent to each recipient, for example in an as-received mode. In addition, the recipient can view a list of recipients for each portion. FIG. 10 is a flowchart for explaining the foregoing operation of the preferred embodiment of the invention in creating computerized messages. In step S 1001 , portions of a message including text and/or attachments are authored. By default, all recipients are designated to receive all portions of the message. If it is desired to identify a subset of the recipients as intended recipients for a portion of the message in step S 1002 , flow proceeds to step S 1003 . Otherwise, flow proceeds to step S 1006 . In step S 1003 , it is determined if a portion of the message has been selected. If so, recipients for that portion are identified in step S 1004 . For example, a user could right-click with pointing device 14 , calling up pop-up window 59 . The user could then select or deselect individual recipients, categories of recipients, or sent mail, as desired. Flow then proceeds to step S 1006 . On the other hand, if text has not been selected, flow instead proceeds to step S 1005 , and recipients for subsequently entered portions are identified. For example, a user could call up pop-up window 59 and designate one or more recipients. Then, subsequently-entered text and attachments would be designated as intended for receipt by only those recipients. Flow then proceeds to step S 1006 . In step S 1006 , it is determined if the message should be viewed as received by particular recipients. If the message should be so viewed, flow proceeds to step S 1007 , where those recipients are identified. For example, the recipients can be identified using view pull-down menu 66 . After the appropriate recipients are identified, the message can be viewed as it will be received by those recipients. In any case, flow then proceeds to step S 1008 . In step S 1008 , if more text or another attachment is to be added to the message, flow returns to step S 1001 . Otherwise, if the message is complete, flow proceeds to step S 1009 , where the message is sent. FIG. 11 is a flowchart for describing the operation of E-mail editor 31 in carrying out the foregoing authoring operation. In step S 1101 , E-mail editor 31 accepts portions of a message (i.e., text and/or attachments) entered by a user. Step S 1102 determines if a user has given a command that recipients for text should be identified. If so, flow proceeds to step S 1103 , where a list of recipients such as pop-up window 59 is displayed. In step S 1104 , identification of recipients from the list is accepted. In step S 1105 , a determination is made as to whether one of the portions of the message has been selected, for example as shown by highlighting of text line 56 in FIG. 6 . If one of the portions of the message has been selected, flow proceeds to step S 1106 , where the selected portion of the message is associated with the recipients identified in step S 1104 . Otherwise, flow proceeds to step S 1107 , where E-mail editor 31 determines that subsequently entered portions of the message will be associated with the recipients identified in step S 1104 . In either case, flow then proceeds to step S 1108 , where visual cues are provided indicating the associations between portions of the message and recipients. These visual cues can be in the form of underlining, color schemes, or other forms of highlighting. If no command has been given to identify recipients, or after visual cues have been provided, flow proceeds to step S 1109 . In step S 1109 , it is determined if a command has been given to view the message as it will be received by particular recipients. Such a command can be given using as-received line 68 of view pull-down menu 66 . If a command has been given to view the message as received, flow proceeds to step S 1110 . Otherwise, flow proceeds to step S 1113 . In step S 1110 , a list of recipients is displayed, such as list 69 . Identification of recipients is accepted in step Slll, and portions of text associated with the identified recipients are displayed in step S 1112 . Thereafter, flow proceeds to step S 1113 . In step S 1113 , it is determined if a command has been given to send the message. If not, flow returns to step S 1101 , where more text and attachments can be entered into the message. If a command has been given to send the message, flow proceeds to step S 1114 . In step S 1114 , E-mail editor 31 generates A separate messages corresponding to each subset of identified recipients. For example, for the message shown in FIG. 6, separate messages are made for the following groups of recipients: (1) “Team Member 2” and “Team Member 3”; (2) “Team Member 1”, “Manager” and “President”; and (3) “Manager” and “President”. Each separate message contains only those input portions associated with the corresponding identified subset of recipients. FIG. 12 is a flowchart for describing viewing of a message according to the preferred embodiment of the invention. In step S 1201 , a message is viewed, preferably including visual cues indicating which portions of the message are intended for less than all of the recipients. If it is desired in step S 1202 to see which recipients will receive a particular portion of the text, flow proceeds to step S 1203 . Otherwise, flow proceeds to step S 1205 . In step S 1203 , a portion of text is placed in focus. Then, in step S 1204 , a list of recipients of the text in focus is called up. Next, flow proceeds to step S 1205 . In step S 1205 , it is determined if the message should be viewed as received by one or more particular recipient(s). If the message should be so viewed, a recipient or category of recipients is identified in step S 1206 . Then, the message can be viewed as received by the identified recipient(s). In any case, flow proceeds to step S 1207 , where it is determined if the viewing process is complete. If not, flow returns to step S 1201 . Otherwise, flow proceeds to step S 1208 , where the viewing process exits. FIG. 13 is a flowchart for describing the operation of E-mail reader 32 in performing the viewing operation described above. In step S 1301 , E-mail reader 32 displays text and icons for attachments for a message, preferably including visual cues indicating portions of the message that were received by fewer than all recipients. In step S 1302 , it is determined whether a command has been given to identify recipients of a particular portion of the message. In that case, flow proceeds to step S 1303 , where E-mail reader 32 determines where the user's focus is in the message. Then, a list of recipients corresponding to the text in focus is displayed in step S 1304 . The list preferably is displayed in a pop-up window such as pop-up window 88 . The list can include all possible recipients, with those recipients who receive the in-focus portion of the message being designated with, for example, check marks. Alternatively, the list can include only those recipients who receive the in focus portion. In step S 1305 , which follows steps S 1302 and S 1304 , it is determined whether a command has been given to view the message as received by one or more particular recipient(s). If so, flow proceeds to step S 1306 , where a list of recipients and categories of recipients is displayed. In step S 1307 , identification of recipient(s) is accepted, and in step S 1308 , portions of text associated with the identified recipient(s) are displayed. In any case, flow proceeds to step S 1309 , where it is determined if a command to exit E-mail reader 32 has been given. If such a command has not been given, flow returns to step S 1301 . Otherwise, flow proceeds to step S 1310 , where E-mail reader 32 exits. The invention has been described with respect to a particular illustrative embodiment. It is to be understood that the invention is not limited to the details of the above-described embodiment and that various changes, and that modifications may be made by those of ordinary skill in the art without departing from the spirit and scope of the invention.
A computerized messaging system which authors messages that contain recipient-specific content, such that each recipient does not necessarily receive a message that is identical to all other recipients. To author a computerized message that contains recipient-specific content, plural portions of the message are authored, and one or more recipients to which at least one portion of the message will be sent are identified. For each recipient, at least one portion of the message is associated with the recipient, such that at least one recipient does not receive all portions of the message. Viewing options are provided to the sender so as to enable the sender to obtain visual cues as to which portions of the message are sent to each recipient or set of recipients, or to allow the sender to view a recipient list for selected portions of the message. At the receiving side, a recipient can view a received message with visual cues such that recipients of private portions of a message can know that others did not receive the private portion, and can further know who received which portions.
8
RELATED APPLICATION [0001] The present application is a divisional application of, and claims the priority under 35 U.S.C. § 120 of, U.S. patent application Ser. No. 10/422,002 filed Apr. 22, 2003, which application is incorporated herein by reference in its entirety. BACKGROUND [0002] Optical discs have fast become an industry standard for data storage in the fields of computers, video, and music. Optical discs include, but are not limited to, compact discs (CDs), Digital Video (or Versatile) Discs (DVDs) and game system discs in a variety of formats. Commercially produced optical discs usually have digital data recorded on one side of the disc and a visual display printed on the other side of the disc. [0003] In some instances, optical discs are created that can store data on both sides of the disc. However, in many cases, it is desirable to limit the optical disc data to a single side of the disc, leaving the other side of the disc for printed text, patterns or graphics. The printed labeling on a non-data side of an optical disc can include a decorative design, text identifying the data stored on the disc, or both. [0004] As optical technology has advanced, writeable and rewritable optical discs and equipment for writing onto the discs have become reasonably priced within the grasp of ordinary consumers. Thus, many consumers currently have the ability to store data on an optical disc with home office equipment. [0005] However, very specialized and expensive equipment is required to print labeling on an optical disc. Consequently, the labeling of discs by most consumers is typically limited to printing on separate adhesive labels that are adhered to the non-data side of the disc or hand-writing with a marker directly on the disc or an adhesive label. SUMMARY [0006] A method of labeling an object includes selectively applying focused energy to thermally conductive pads on the object to create a label on the object. The conductive pads are disposed adjacent to a thermochromic layer. of independent claim BRIEF DESCRIPTION OF THE DRAWINGS [0007] The accompanying drawings illustrate various embodiments of the principles described herein and are a part of the specification. The illustrated embodiments are merely examples and do not limit the scope of the claims. [0008] FIG. 1 is an exploded view of an optical disc and detailed inset according to principles described herein. [0009] FIG. 2 is an exploded view of another optical disc and detailed inset according to principles described herein. [0010] FIG. 3 is an exploded view of another optical disc and detailed inset according to principles described herein. [0011] FIG. 4A is a side view of a first layer of an optical disc according to principles described herein. [0012] FIG. 4B is a side view of first and second layers of an optical disc according to principles described herein. [0013] FIG. 4C is a side view of first, second, and third layers of an optical disc according to principles described herein. [0014] FIG. 4D is a side view of first, second, third, and fourth layers of an optical disc according to principles described herein. [0015] FIG. 5 is a diagrammatical side view of an optical disc labeling system according to principles described herein. [0016] FIG. 6 is a top view of an optical disc with a label made according to principles described herein. [0017] Throughout the drawings, identical reference numbers designate similar, but not necessarily identical, elements. DETAILED DESCRIPTION [0018] Writeable and rewritable optical disks include materials that change optical properties (e.g. reflection, refraction, absorption, transmission, diffraction, and scatter) when heated by a focused energy source (e.g. a writing laser). By selectively changing the optical properties of particular points along an optical disc's spiral data track and leaving other areas unaffected, digital data is recorded on the disk that computers and/or audiovisual equipment can read. Some changes in optical properties, for example, a change in reflectivity, are also readily visible to consumers and typically indicate that data is stored on the optical disc. Therefore, in addition to storing data on an optical disc, it is also possible to create visible printed patterns or graphical designs on the disc by selectively changing the optical properties of portions of the disc. [0019] However, lasers used to write data onto the optical disk data track are very tightly focused and of very high resolution (about 12,000 dpi) to facilitate storage of very large amounts of data. Such high resolution lasers require thousands of laser strikes to create one 300 dpi visible spot. Consequently, it would take a very long time, perhaps an hour or more, to write a small printed pattern or graphical design onto a conventional optical disc in this manner. As a result, it is not common currently for printed patterns and/or graphical designs to be written onto conventional optical discs using the same laser that also writes digital data to the disc. [0020] The present specification describes a mass media storage device, such as an optical disc, and methods of making and using such an optical disc. The specification also describes methods of labeling mass media storages devices or any other object by the application of focused energy. [0021] As used in this specification and the appended claims, the term “optical disc” is used broadly to encompass discs for recording music, pictures, video and/or software, etc. An optical disc includes, but is not limited to, writable and rewritable storage devices including, but not limited to, Compact Discs (CDs), Compact Disc Read-Only Memory (CD-ROMs) and Digital Video (or Versatile) Discs in various formats. [0022] “Label” or “labeling” means any text, printed pattern, graphical design or combination thereof on an object. If a label is added to an optical disc, typically the label is found on one side of the optical disc, although this is not necessarily the case. “Printed pattern”, means any text, letters, words, symbols, or characters that are found on an object as part of a label for that object. “Graphical design” means any graphic or image that is found on an object as part of a label for that object. “Uniform” means having the same or substantially the same design or pattern throughout. [0023] As mentioned above, it is possible to write labels on current optical discs by applying a laser to the discs in certain patterns. The application of the laser changes the optical properties (such as reflectivity) of the exposed portions of the disc, resulting in patterns that can be made large enough to be visible to users. Lasers for writing digital, machine-readable data on optical discs are typically focused at about 2.2 μm. Therefore, if such a laser is used to also write a label onto a disc, because of the extremely small pixel size that would result, it takes a very long time to produce labels. [0024] While typically, the smaller the pixel size, the better resolution in a printed product, a 2.2 μm pixel size is unnecessarily to print a quality label. Therefore, an optical disc is described below for facilitating faster labeling without compromising data storage capability. Subsequent to the description of the optical disc itself, methods for making an optical disc are discussed, followed by a discussion of actually creating a label on the optical disc. However, it will be understood that the methods described herein are not limited to labeling optical discs. The methods and apparatus described below may be implemented with any object to facilitate labeling by the application of focused energy. The particular implementations described below with reference optical discs are therefore exemplary in nature, and not limiting. For example, the labeling techniques and apparatus described below may be applied to bottles, cans, or any other objects. [0025] In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the present systems and methods. It will be apparent, however, to one skilled in the art that the present systems and methods may be practiced without these specific details. Reference in the specification to “an embodiment,” “an example” or similar language means that a particular feature, structure, or characteristic described in connection with the embodiment or example is included in at least that one embodiment, but not necessarily in other embodiments. The various instances of the phrase “in one embodiment” or similar phrases in various places in the specification are not necessarily all referring to the same embodiment. [0026] Turning now to the figures, and in particular FIG. 1 , an exploded view of an optical disc ( 100 ) is shown according to the principles described herein. The optical disc ( 100 ) includes a label side ( 102 ) designed to facilitate labeling thereon by the application of focused energy. Instead of a long spiral track or an unusable surface typical of most optical discs, the label side ( 102 ) of the optical disc ( 100 ) includes a plurality of thermally conductive pads ( 104 ) formed on an insulating layer ( 106 ). The insulating layer ( 106 ) may include a polymer or other insulating material. The thermally conductive pads ( 104 ) formed on the insulating layer ( 106 ) are shown in a detailed inset ( 108 ) as they are generally not visible to the naked eye. The making of the thermally conductive pads ( 104 ) is discussed in detail below with reference to FIGS. 4 A-B. [0027] As shown in FIG. 1 , the thermally conductive pads ( 104 ) are each distinct and may be hexagonal. However, while the hexagonal shapes shown can be densely packed, the shape of the thermally conductive pads ( 104 ) is not so limited. Any polygonal shape, and any other shape including any combination of straight and/or curved lines, may also be used for the pads ( 104 ). For example, the thermally conductive pads ( 104 ) may be circular as shown in FIG. 2 , or elliptical as shown in FIG. 3 . [0028] The size of the thermally conductive pads ( 104 ) can be set at any desired size and will correspond to the size of a pixel in the label that is to be produced on the disc ( 100 ). For example, the size of the thermally conductive pads may be larger than approximately 5 μm. In some examples, the size of the conductive pads ( 104 ) is between approximately 5 and 50 μm. Within that range, in some examples, the size of the conductive pads is about 32 μm. [0029] The thermally conductive pads ( 104 ) are arranged adjacent to a thermochromic layer ( 110 ) that is discussed in more detail below with reference to FIGS. 4 C-D. The thermochromic layer ( 110 ) includes thermochromic materials that change in optical density when heated. Changes in optical density may be visible to the human eye and expressed in a variety of different colors, depending on the thermochromic material. For example, the thermochromic layer ( 110 ) may include leuco dye. The thermochromic layer ( 110 ) may be covered with an optically transparent layer ( 112 ) to protect the thermochromic layer ( 110 ) from scratches or other damage. Preferably, the optically transparent layer ( 112 ) will not absorb energy of wavelengths associated with lasers typically used to read and/or write optical discs. The optically transparent layer ( 112 ) may be polycarbonate or another material and is also discussed below with reference to FIG. 4D . [0030] The pixel size of the thermally conductive pads ( 104 ) is substantially larger than the typical focus size of an optical writing laser, facilitating faster labeling than previously possible using a focused energy emission source, such as an optical writing laser. As suggested by the name, each of the thermally conductive pads ( 104 ) includes a thermally conductive material. The thermally conductive material may include, for example, carbon or other thermal conductors. Accordingly, a focused energy source may direct energy to any portion of an individual thermally conductive pad ( 104 ), and the thermally conductive pad ( 104 ) will absorbs the energy and substantially evenly distributes the absorbed energy across the pad. [0031] As the energy is absorbed and distributed across the thermally conductive pad ( 104 ), the temperature of the pad increases. When the conductive pad ( 104 ) increases in temperature, the pad ( 104 ) transfers heat to portions of the thermochromic layer ( 110 ) adjacent to the pad ( 104 ). The heat transferred to the thermochromic layer ( 110 ) results in an optical density change for that portion of the thermochromic layer ( 110 ) that is heated. By selectively applying focused energy to the thermally conductive pads ( 104 ), a label of printed patterns and/or graphical designs may be quickly added to the optical disc ( 100 ) in the thermochromic layer ( 110 ). [0032] Instead of selectively writing a label to the optical disc ( 100 ) with a 2.2 μm pixel size, the use of the thermally conductive pads ( 104 ) facilitates writing labels with a pixel size of 5-50 μm or greater, corresponding to the size of the thermally conductive pads ( 104 ). This decreases the labeling write time by about 2-20 times or more. In addition to the example of an optical disc, the thermally conductive pads ( 104 ) may be combined with a thermochromic layer ( 110 ) and added to any other object to facilitate labeling of that object. [0033] In addition to enabling faster label creation, the introduction of the thermally conductive pads ( 104 ) may add to the accuracy of the labels. A typical 2.2 μm pixel created by writing to conventional optical discs tends to be misshaped (tear-shaped or elliptical) because of the rotation of the optical disc during writing. The use of specially shaped thermally conductive pads ( 104 ) ensures a desired pixel size and shape. And, although the thermally conductive pads ( 104 ) shown are all the same size, this is not necessarily so. The size and shapes of the thermally conductive pads ( 104 ) of an object may be uniform as shown, or may vary. Further, use of the relatively large thermally conductive pads ( 104 ) increases tolerance for positional errors of the focused energy emission source. Energy may be directed to any portion of the conductive pad ( 104 ), and the pad ( 104 ) will still substantially evenly distribute the energy and uniformly heat the thermochromic layer ( 110 ). [0034] The optical disc ( 100 ) (or other object) with the thermally conductive pads ( 104 ) may be made according to any of a number of methods. Particular methods of manufacture are discussed below, however, the methods discussed below are exemplary in nature and not limiting. Turning to FIGS. 4 A-D, a series of side view images of the optical disc ( 100 ) is shown in various stages of disc manufacture. According to one embodiment, the manufacture of the optical disc ( 100 ) includes indenting the insulating layer ( 106 ). As mentioned above, the insulating layer ( 106 ) may be a polymer or other deformable material. A pattern, preferably a uniform pattern, is stamped into the insulating layer ( 106 ) to form a plurality of indentations ( 400 ). The shape of the indentations (from a top view) corresponds with the hexagonal, curved, circular, elliptical, or other shapes discussed above and/or shown in FIGS. 1-3 as being possible shapes for the thermally conductive pads. The pattern may be stamped with a rigid die or other tool. Alternatively, the pattern of indentations ( 400 ) may be microembossed into the insulating layer ( 106 ) or screen-printed onto the insulating layer ( 106 ). Other methods of forming the indentations ( 400 ) may also be used. [0035] After indenting a pattern onto the insulating layer ( 106 ), a thermally conductive material is deposited onto the insulating layer ( 106 ) and/or into the indentations ( 400 ). For example, a thermally conductive material such as carbon in a solvent may be fluidly layered across the insulating layer ( 106 ). One example of a carbon/solvent mixture is ink commonly used in inkjet printers. Following application of a liquid conductive layer, the solvent is allowed to evaporate, leaving the solid carbon or other thermally conductive material in the indentations ( 400 ). Alternatively, the thermally conductive material may be inserted directly into the individual indentations ( 400 ), and there may be no need for an evaporation time allowance. The thermally conductive material disposed in the indentations defines the thermally conductive pads ( 104 ) shown in FIG. 4B . [0036] Following the formation of the thermally conductive pads ( 104 ), the thermochromic layer ( 110 ) is disposed over the thermally conductive pads ( 104 ) and the insulating layer ( 106 ) as shown in FIG. 4C . The thermochromic layer ( 110 ) may include leuco dye or other materials known to change color with the application of heat. Preferably, the thermochromic layer ( 110 ) is initially transparent to the wavelength of light generated by an energy emitter, for example, a writing laser. The material of the thermally conductive pads ( 104 ), on the other hand, is highly absorptive of the wavelength of energy emitted. [0037] An optically transparent layer ( 112 ) may be disposed over the thermochromic layer ( 10 ) as shown in FIG. 4D , although this is not necessarily so. According to some embodiments, there is no optically transparent layer ( 112 ) in addition to the thermochromic layer ( 110 ). The transparent layer ( 112 ) may be, for example, polycarbonate or some other protective material. The transparent layer ( 112 ) may be spin-coated onto the thermochromic layer ( 110 ) and protects the thermochromic layer ( 110 ) and/or the conductive pads ( 104 ) from scratches or other damage. [0038] It will be understood that opposite of the label side ( 102 , FIG. 1 ) of the optical disc ( 100 , FIG. 1 ) will normally be a data side ( 114 , FIG. 1 ). The data side ( 104 , FIG. 1 ) may be fabricated according to conventional methods that are well known to those of skill in the art having the benefit of this disclosure. The data side ( 104 , FIG. 1 ) therefore includes all of the layers typical of writable or rewritable optical discs in various formats. However, according to some embodiments, there may be two label sides ( 102 , FIG. 1 ) and no data side ( 104 , FIG. 1 ). According to embodiments with two label sides ( 102 , FIG. 1 ), only printed patterns and graphical designs may be created, and no digital data may be recorded. [0039] In an alternative construction, a specialty film could be made to include the thermally conductive pads and an insulator. The specialty film could then be applied to an object such as an optical disc, but it may also be added to any other object to facilitate labeling. [0040] According to some aspects of the construction of an optical disc, a label side may also include some permanent information that is human or machine readable. Such permanent information may include, but is not limited to: the optical disc format, the color that will be viewable when the optical density of the thermochromic layer is changed, etc. [0041] Turning now to a discussion of an actual labeling operation according to the principles discussed herein, labeling of the optical disc ( 100 , FIG. 1 ) or other objects may be accomplished with a number of commercially available products. For example, a computer with a CD Read/Write (RW) or DVD-RW drive may be used to label the optical disc ( 100 , FIG. 1 ). However, other products capable of writing to optical discs may also be used including, but not limited to, CD and DVD recorders. For purposes of example and discussion, a computer system ( 500 ) that may be used in combination with the optical disc ( 100 ) to generate a label thereon is shown in FIG. 5 . [0042] The computer system ( 500 ) includes a mount ( 502 ) and a motor ( 504 ) for holding and spinning the optical disc ( 100 ). The label side ( 102 ) of the disc ( 100 ) is shown facing the mount ( 502 ) such that a label may be written to the disc ( 100 ). It will be understood, of course, that data may also be written to the data side ( 114 ) of the optical disc ( 100 ) if the disc is turned over. [0043] Positioned to face a portion of the label side ( 102 ) of the optical disc ( 100 ) is a track ( 506 ) providing for movement of a sled ( 508 ) radially with respect to the optical disc ( 100 ). Movement of the sled ( 508 ) is actuated by a solenoid ( 509 ) or other device. A focused energy emitting device or devices, which in the present embodiment includes a first, second and third laser ( 510 , 512 , 514 , respectively), is disposed on the sled ( 508 ). The first laser ( 510 ) is a writing laser with enough power to quickly heat the thermally conductive pads ( 104 , FIG. 1 ) of the optical disc ( 100 ). The second laser ( 512 ) is an erasing laser that may be used, for example, to erase CDRW discs. The third laser ( 514 ) is a read laser and is less powerful than the first and second lasers ( 510 and 512 ) and may be used to emit a beam that is reflected and read by a detector ( 516 ). The detector ( 516 ) is also positioned on the sled ( 508 ). The third laser ( 514 ) is used when reading data from the data side ( 114 ) of the optical disc (or, in some cases, some data from the label side ( 102 )). Signals received by the detector may be conditioned by a signal conditioner ( 515 ) when the system ( 500 ) is in a reading mode. [0044] However, the system ( 500 ) is in a writing mode as shown in FIG. 5 and as the optical disc ( 100 ) spins, a label can be written on the label side ( 102 ) by applying the first laser beam ( 540 ) from the first laser ( 510 ) at selective locations. The system is controlled by a processor ( 520 ). The processor ( 520 ) controls the firing of the lasers ( 510 , 512 , 514 ), the rotation of the motor ( 504 ), and the position of the sled ( 508 ). The first laser ( 510 ) can aim an energy beam ( 540 ) very precisely to hit one or more of the thermally conductive pads ( 104 , FIG. 1 ). [0045] When the energy beam ( 540 ) strikes one of the thermally conductive pads ( 104 , FIG. 1 ), the conductive material evenly distributes the energy across the pad ( 104 , FIG. 1 ) and increases in temperature. The resulting increase in temperature heats a portion of the thermochromic layer ( 110 ) corresponding to the shape and size of the thermally conductive pad ( 104 , FIG. 1 ) that the thermochromic layer ( 110 ) is adjacent to. With an increase in temperature, that portion of thermochromic layer ( 110 ) adjacent to the thermally conductive pads ( 104 , FIG. 1 ) changes optical density and becomes visible, colored or non-transparent. It should be noted that heat transfer from the thermally conductive pad ( 104 , FIG. 1 ) to the thermochromic layer ( 110 ) will continue even after the energy beam ( 540 ) has moved to another pad ( 104 ). Therefore, the label writing process can proceed quickly as the laser ( 510 ) is aimed to strike different conductive pads ( 104 , FIG. 1 ). The laser need only be applied long enough to sufficiently heat the conductive pad ( 104 , FIG. 1 ) and does not have to be applied until the thermochromic layer ( 110 ) has changed optical properties. [0046] The first laser ( 510 ) applies the energy beam ( 540 ) to all locations programmed in the processor ( 520 ) to create a label, e.g., printed pattern and/or graphical display. For example, the first laser ( 510 ) may apply energy to selective thermally conductive pads ( 104 ) to create a printed pattern ( 600 ) or graphical design ( 602 ) as shown in FIG. 6 . An inset ( 604 ) shows that individual pixels ( 606 ) have been selectively colored by the application of energy to associated conductive pads ( 104 ). [0047] The preceding description has been presented only to illustrate and describe embodiments and examples of the principles described. This description is not intended to be exhaustive or to limit these principles to any precise form disclosed. Many modifications and variations are possible in light of the above teaching.
An optical disc includes an optical disc; a thermally conductive material disposed in a pattern of discrete pads on said disc; and a thermochromic material disposed over said pattern of thermally conductive material. A method of making an optical disc includes indenting a pattern onto an insulator; and depositing a thermally conductive material into indents of said pattern.
6
FIELD The present invention relates to image capture devices and methods of operating same and, more particularly, to three-dimensional (3D) image capture devices and methods of operating same. BACKGROUND With the widespread dissemination of cameras, technology for taking three-dimensional (3D) images using information about a distance to an object as well as a two-dimensional image of the object has received attention. A device for acquiring information about a distance to an object and sensing the distance is called a depth sensor. A 3D image sensor that obtains a 3D image using the depth sensor is called a 3D image sensor. The depth sensor measures a delay time between pulse light emitted from a light source which is then reflected from an object and received by the image sensor. A pixel of the depth sensor includes a plurality of photoelectric conversion elements. Each of the photoelectric conversion elements generates photocharge in proportion to the quantity of pulse light emitted by a light source and then reflected and returned from the object. A difference between a time of emission of the pulse light and a time of sensing the pulse light is called a time of flight (TOF). The distance to the object can be calculated from the TOF and the speed of the pulse light. In other words, the depth sensor calculates the distance to the object using the charge generated by the photoelectric conversion element. A 3D image can be realized using the distance calculated by the depth sensor and color information acquired by another sensor. However, the quality of the 3D image may be low due to various types of interference. Techniques for preventing the interference have been developed. SUMMARY An image capture device according to some embodiments of the invention includes an image sensor having an array of pixels therein, which are configured to receive light reflected from an object during an image capture time interval. This image sensor may include an image sensor pixel array, a row address decoder, a row driver, a column driver and a column address decoder, for example. A light source is also provided, which is configured to project light to the object during at least a portion of the image capture time interval. Among other things, this light source is provided to facilitate the capture of three-dimensional (3D) depth information relating to the object. A control circuit/unit is provided, which is electrically coupled to the image sensor and the light source. This control circuit is configured to drive the light source with signals that cause the light source to continuously project light to the object (without interruption) during at least a first time interval (t SRA ) when all rows of a frame of pixels within the array are being sequentially read (and then immediately reset) to yield a first frame of image data and during a second time interval (t SRA ) when all rows of the frame of pixels within the array are being sequentially read to yield a second frame of image data. According to additional embodiments of the invention, the control circuit may be further configured to drive the light source with signals that cause the light source to terminate projection of light to the object during a time interval (t LED1 ) when all of the rows of the frame of pixels within the array are concurrently capturing image data and none of the rows are being read. This control circuit may also be configured to drive the image sensor with signals that cause the frame of pixels to collect three-dimensional (3D) depth information associated with the first and second frames of image data during the first and second time intervals and also during a data integration time interval (t VB ) extending between the first and second time intervals. According to additional embodiments of the inventive concept, there is provided an image sensor control method including the operations of performing a readout operation and a reset operation on first through n-th rows sequentially in a pixel array, where “n” is an integer of at least 2; turning off a light source for a first duration after completing the readout and reset operations; and performing the readout and reset operations on the first through n-th rows sequentially in the pixel array after the first duration elapses. The operation of performing the readout and reset operations on the first through n-th rows sequentially in the pixel array may include turning on and off a select transistor and a reset transistor comprised in each pixel in the first through n-th rows sequentially in the pixel array. The operation of performing the readout and reset operations on the first through n-th rows sequentially in the pixel array after the first duration elapses may include turning on and off the select transistor and the reset transistor comprised in each pixel in the first through n-th rows sequentially in the pixel array. The light source may be a light emitting diode. According to further embodiments of the inventive concept, there is provided an image sensor control method including the operations of performing a readout operation, a reset operation, and an integration operation on first through n-th rows sequentially in a pixel array at least two times, where “n” is an integer of at least 2; turning off a light source after repeating the readout, reset, and integration operations of the first through n-rows at least two times and turning on the light source after a first duration elapses; and performing the readout, reset, and integration operations on the first through n-th rows sequentially in the pixel array at least two times after the light source is turned on. The readout, reset, and integration operations may be performed by turning on and off a transfer transistor, a select transistor, and a reset transistor, which are comprised in each cell in the first through n-th rows in the pixel array. The operation of performing the readout operation, the reset operation, and the integration operation on the first through n-th rows sequentially in the pixel array at least two times may include performing the readout, reset, and integration operations on each row four times. BRIEF DESCRIPTION OF THE DRAWINGS The above and other features and advantages of the inventive concept will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings in which: FIG. 1 is a block diagram of an image sensor according to some embodiments of the inventive concept; FIGS. 2A through 2D are circuit diagrams of examples of a pixel included in a pixel array of the image sensor illustrated in FIG. 1 ; FIG. 3 is a timing chart showing an image sensor control method using a rolling shutter in a comparison example; FIG. 4 is a timing chart showing an image sensor control method according to some embodiments of the inventive concept; FIG. 5 is a flowchart of the image sensor control method illustrated in FIG. 4 ; FIG. 6 is a timing chart showing an image sensor control method according to other embodiments of the inventive concept; FIG. 7 is a flowchart of the image sensor control method illustrated in FIG. 6 ; and FIG. 8 is a schematic block diagram of a semiconductor system including the image sensor using an image sensor control method according to some embodiments of the inventive concept. DETAILED DESCRIPTION OF THE EMBODIMENTS The inventive concept now will be described more fully hereinafter with reference to the accompanying drawings, in which embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. In the drawings, the size and relative sizes of layers and regions may be exaggerated for clarity. Like numbers refer to like elements throughout. It will be understood that when an element is referred to as being “connected” or “coupled” to another element, it can be directly connected or coupled to the other element or intervening elements may be present. In contrast, when an element is referred to as being “directly connected” or “directly coupled” to another element, there are no intervening elements present. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items and may be abbreviated as “/”. It will be understood that, although the terms first, second, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first signal could be termed a second signal, and, similarly, a second signal could be termed a first signal without departing from the teachings of the disclosure. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” or “includes” and/or “including” when used in this specification, specify the presence of stated features, regions, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, regions, integers, steps, operations, elements, components, and/or groups thereof. Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and/or the present application, and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein. FIG. 1 is a block diagram of an image sensor 100 according to some embodiments of the inventive concept. The image sensor 100 illustrated in FIG. 1 uses an image sensor control method according to some embodiments of the inventive concept and is used to obtain a three-dimensional (3D) image signal. The image sensor 100 includes a light source 120 , a pixel array 140 , a control unit 112 , a row address decoder 114 , a row driver 115 , a column driver 117 , a column address decoder 118 , a sample and hold (S/H) block 152 , an analog-to-digital converter (ADC) 154 , and an image signal processor (ISP) 156 . The light source 120 may emit light to an object 130 according to the control of the control unit 112 . Although any of various types of light emitting devices that can emit modulated light may be used as the light source 120 , a light emitting diode (LED) may be usually used as the light source 120 . The pixel array 140 may have a structure in which a plurality of pixels ( 148 a , 148 b , 148 c , or 148 d ), which will be described with reference to FIGS. 2A through 2D , are arranged in a matrix form. The pixels included in the pixel array 140 may output pixel signals (e.g., a color image signal and a distance signal) by columns in response to a plurality of control signals generated by the row driver 115 . The control unit 112 may output a plurality of control signals for controlling the operations of the light source 120 , the pixel array 140 , the row address decoder 114 , the row driver 115 , the column driver 117 , the column address decoder 118 , the S/H block 152 , the ADC 154 , and the ISP 156 and may generate addressing signals for the output of signals (e.g., a color image signal and a distance signal) sensed by the pixel array 140 . In detail, the control unit 112 may control the row address decoder 114 and the row driver 115 to select a row line to which a certain pixel is connected, so that a signal sensed by the certain pixel among a plurality of pixels included in the pixel array 140 is output. In addition, the control unit 112 may control the column driver 117 and the column address decoder 118 to select a column line to which a certain pixel is connected. The control unit 112 may also control the light source 120 to emit light periodically and may control on/off timing of photoelectric conversion elements for sensing a distance in pixels included in the pixel array 140 . The row address decoder 114 decodes a row control signal output from the control unit 112 and outputs the decoded row control signal. The row driver 115 selectively activates a row line in the pixel array 140 in response to the decoded row control signal. The column address decoder 118 decodes a column control signal (e.g., an address signal) output from the control unit 112 and outputs the decoded column control signal. The column driver 117 selectively activates a column line in the pixel array 140 in response to the decoded column control signal. The S/H block 152 may sample and hold a pixel signal output from a pixel selected by the row driver 115 and the column driver 117 . In detail, the S/H block 152 may sample and hold signals output from a pixel selected by the row driver 115 and the column driver 117 among the plurality of pixels included in the pixel array 140 . The ADC 154 may perform analog-to-digital conversion on signals output from the S/H block 152 and output digital pixel data. At this time, the S/H block 152 and the ADC 154 may be integrated into a single chip. The ADC 154 may include a correlated double sampling (CDS) circuit (not shown), which performs CDS on signals output from the S/H block 152 . At this time, the ADC 154 may compare a CDS signal with a ramp signal (not shown) and output a comparison result as the digital pixel data. The ISP 156 may perform digital image processing based on the pixel data output from the ADC 154 . The ISP 156 may receive a signal generated by the pixels included in the pixel array 140 , sense a time of flight (TOF) from the signal, and calculate a distance to the object 130 . The ISP 156 may also interpolate an RGBZ Bayer signal and generate a 3D image signal using the interpolated signal. In addition, the ISP 156 may perform edge enhancement and pseudo-color suppression. FIGS. 2A through 2D are circuit diagrams of examples of a pixel included in the pixel array 140 of the image sensor 100 illustrated in FIG. 1 . Referring to FIG. 2A , a unit pixel 148 a includes a photodiode PD, a transfer transistor Tx, a floating diffusion node FD, a reset transistor Rx, a drive transistor Dx, and a select transistor Sx. The photodiode PD is an example of a photoelectric conversion element. The photodiode PD may include at least one among a photo transistor, a photo gate, a pinned photodiode (PPD), and a combination thereof. FIG. 2A shows a 4-transistor (4T) structure that includes a single photodiode PD and four MOS transistors Tx, Rx, Dx, and Sx, but the present invention is not restricted to this example (see, e.g., FIGS. 2B-2D ). Any circuits including at least three transistors including the drive transistor Dx and the select transistor Sx and the photodiode PD may be used in the embodiments of the present invention. In the operation of the pixel 148 a , reflective light Rf_light reflected from the object 130 is incident on the pixel 148 a and the photodiode PD generates photocharge varying with the intensity of the reflective light Rf_light. The transfer transistor Tx may transfer the photocharge to the floating diffusion node FD in response to a transfer control signal TG received from the control unit 112 . The drive transistor Dx may transmit photocharge to the select transistor Sx based on the photocharge accumulated at the floating diffusion node FD. The select transistor Sx may output a pixel signal along a column line connected to the pixel 148 a in response to a select signal SEL received from the control unit 112 . The reset transistor Rx may reset the photocharge accumulated at the floating diffusion node FD in response to a reset signal RS received from the control unit 112 . Referring to FIG. 2B , an alternative unit pixel 148 b has a 3-transistor (3T) structure that includes a photodiode PD, a reset transistor Rx, a drive transistor Dx, and a select transistor Sx. Referring to FIG. 2C , another unit pixel 148 c can have a 5-transistor (5T) structure that includes a photodiode PD, a transfer transistor Tx, a reset transistor Rx, a drive transistor Dx, a select transistor Sx, and one more transistor Gx. Referring to FIG. 2D , a unit pixel 148 d can have a 5T structure that includes a photodiode PD, a transfer transistor Tx, a reset transistor Rx, a drive transistor Dx, a select transistor Sx, and one more transistor Px. A node N1 connected to the one more transistor Px may be connected to a pixel adjacent to the unit pixel 148 d. FIG. 3 is a timing chart showing an image sensor control method using a rolling shutter in a comparison example. Referring to FIG. 3 , an integration cycle for each pixel begins with reset and ends with readout. A complementary metal oxide semiconductor (CMOS) image sensor performs reset, integration, and readout operations using a rolling shutter method by which the reset and readout operations are performed on pixels in different rows at different times. In other words, rows in the pixel array 140 are sequentially subjected to the sequential reset and readout operations. For instance, at the moment when integration starts on a first row after the completion of readout and reset of the first row, readout and reset may start on a second row. In the same manner, the following rows are sequentially subjected to readout and reset. After reset is completed with respect to an n-th row (where “n” is an integer of at least 2 and “n” is 12 in the comparison example illustrated in FIG. 3 ), readout of the next frame may be started. In FIG. 3 , t SR denotes a time taken to complete the readout and reset operations with respect to a single row, t INT denotes a time taken to complete the integration operation of a single row, and t F denotes a time taken to complete a single cycle of readout, reset, and integration on a single row. The time t F may be defined as t F =t SR +t INT . The times t SR and t INT may be controlled to be the same in each row or frame. Adjusting the light emission time of the light source 120 in an image sensor is necessary to prevent over-saturation and under-exposure. The over-saturation is a phenomenon in which depth information for calculation of a distance to an object is entirely lost because an output signal of the pixel array 140 is saturated due to an excessive light emission time of the light source 120 . The under-exposure is a phenomenon in which depth information is damaged by a low signal-to-noise ratio (SNR) caused by background illumination resulting from an insufficient light emission time of the light source 120 . The background illumination is a phenomenon in which interference is raised by a light other than the light source 120 of the image sensor. The SNR indicates the strength of a signal against noise. As the SNR increases, the quality of an image also increases. Accordingly, it is necessary to periodically turn on and off the light source 120 in order to prevent the over-saturation and reduce power consumption of the image sensor. A time t LED denotes a time while the light source 120 is off. As shown by FIG. 3 , the light source 120 is turned off at a time point t OFF and turned on at a time point t ON to reduce the over-saturation and the power consumption. However, depth information may be damaged by the on/off operation of the light source 120 . In detail, the light of the light source 120 is radiated at the first through seventh rows during the integration time t INT in a first frame (which is a period during which a first cycle of readout, reset, and integration is completed with respect to the first through n-th rows) while the light is radiated at the eighth through n-th rows during time less than the integration time t INT . In other words, for instance, the light of the light source 120 is radiated at the twelfth rows in a second frame during the integration time t INT while the light is radiated at the twelfth row in the first frame during time less than the integration time t INT . As described above, because the radiation time of light from the light source 120 is irregular between rows in one frame and between adjacent frames during the integration time t INT , depth information is damaged. FIG. 4 is a timing chart showing an image sensor control method according to some embodiments of the inventive concept. Referring to FIG. 4 , t SRA denotes a time during which a cycle of readout and reset is completed with respect to all of first through n-th rows (where “n” is an integer of at least 2) and t VB is a time obtained by subtracting the time t SRA from the time t F . For convenience, it is assumed that “n” is 12. The time t SR illustrated in FIG. 4 is shorter than the time t SR illustrated in FIG. 3 . The time t SR may be adjusted by controlling the timing of the reset signal RS applied to the reset transistor Rx and the select signal SEL applied to the select transistor Sx using the control unit 112 . However, the inventive concept is not restricted to the current embodiments. The time t SR may be adjusted using various other circuits. It is assumed that readout, reset, and integration of the pixel array 140 has been completed with respect to a first frame. Thereafter, a readout operation may be performed on each of the pixels included in the first row of the pixel array 140 with respect to a second frame. In other words, the select transistor Sx of each pixel in the first row is turned on by the select signal SEL output from the control unit 112 , so that photocharge at the floating diffusion node FD is output to the column driver 117 via the drive transistor Dx. After a predetermined time during which the photocharge is output through the select transistor Sx, the select transistor Sx of each pixel in the first row is turned off and then a reset operation may be performed on the first row. In other words, the reset transistor Rx of each pixel in the first row is turned on by the reset signal RS output from the control unit 112 , so that photocharge remaining in the floating diffusion node FD is eliminated. After a predetermined period of the reset operation, the reset transistor Rx is turned off and then a readout operation may be started with respect to the second row. In addition, photocharge integration may be started with respect to the first row in parallel with the start of the readout operation on the second row. In other words, the transfer transistor Tx of each pixel in the first row is turned on by the transfer control signal TG output from the control unit 112 , so that photocharge generated by the photodiode PD is transferred to the floating diffusion node FD. These readout and reset operations may be repeated with respect to the rows sequentially until the reset operation of the twelfth row is completed. The time t SR taken to complete the readout and reset operations with respect to each row may be adjusted by controlling the timing of the select signal SEL, the reset signal RS, and the transfer control signal TG output from the control unit 112 . After the readout and reset operations on the first through twelfth rows are completed, that is, after the time t SRA elapses, the light source 120 may be turned off by the control unit 112 . Until a readout operation on each pixel in the first row of the pixel array 140 is started with respect to a third frame, the off state of the light source 120 may be maintained for a first duration t LED1 . The first duration t LED1 is a period of time while the light source 120 is off, and it may be less than or equal to the time t VB . While the light source 120 is off, the under-exposure phenomenon in which the SNR decreases may occur in the second frame since light radiation time is not sufficient. Accordingly, it is necessary to stop accumulating photocharge at the floating diffusion node FD for a second duration (not shown) during which the light source 120 is off for the first duration t LED1 . In other words, the transfer transistor Tx of every pixel in the first through twelfth rows of the pixel array 140 is simultaneously turned off by the transfer control signal TG output from the control unit 112 , so that photocharge generated by the photodiode PD is blocked from being transferred to the floating diffusion node FD. After the second duration elapses, the transfer transistor Tx is turned on, so that the photocharge resumes to be transferred to the floating diffusion node FD. The second duration refers to a period of time while accumulation of photocharge at the floating diffusion node FD is stopped, and it may be included in the first duration t LED1 . After the first duration t LED1 elapses, the light source 120 is turned on, and a readout operation may be performed on each pixel in the first row of the pixel array 140 with respect to the third frame. In other words, the select transistor Sx of each pixel in the first row is turned on by the select signal SEL output from the control unit 112 , so that photocharge at the floating diffusion node FD is output to the column driver 117 via the drive transistor Dx. After the predetermined time during which the photocharge is output through the select transistor Sx, the select transistor Sx of each pixel in the first row is turned off and then a reset operation may be performed on the first row. In other words, the reset transistor Rx of each pixel in the first row is turned on by the reset signal RS output from the control unit 112 , so that photocharge remaining in the floating diffusion node FD is eliminated. After the predetermined period of the reset operation, the reset transistor Rx is turned off and then a readout operation may be started with respect to the second row. In addition, photocharge integration may be started with respect to the first row in parallel with the start of the readout operation on the second row. In other words, the transfer transistor Tx of each pixel in the first row is turned on by the transfer control signal TG output from the control unit 112 , so that photocharge generated by the photodiode PD is transferred to the floating diffusion node FD. These readout and reset operations may be repeated with respect to the rows sequentially until the reset operation of the twelfth row is completed. When the operation of the image sensor 100 is controlled as described above, the radiation time of the light from the light source 120 is maintained constant with respect to the first through twelfth rows in the second frame during photocharge integration of each row. Although the 12 rows exist in the pixel array 140 in the current embodiments illustrated in FIG. 4 , the inventive concept is not restricted thereto. It is also illustrated in FIG. 4 that the light source 120 is turned off only in the second frame, but the inventive concept is not restricted to the current embodiments. The light source 120 may be turned off in every frame or every m frame in order to prevent the over-saturation and the under-exposure, where “m” is an integer of at least 2. In the image sensor control method according to the current embodiments, the radiation time of light from the light source 120 is the same with respect to all of rows included in the pixel array 140 during the photocharge integration of each row even if the light source 120 is turned off, so that the quality of images is increased. In addition, the photocharge integration is stopped together with the off of the light source 120 , thereby preventing the SNR from decreasing. FIG. 5 is a flowchart of the image sensor control method illustrated in FIG. 4 . Referring to FIGS. 4 and 5 , readout and reset operations may be performed on the first through n-th rows sequentially in the pixel array 140 in operation S 510 . At this time, a readout operation on each pixel included in the first row of the pixel array 140 may be performed first. In other words, the select transistor Sx of each pixel in the first row is turned on by the select signal SEL output from the control unit 112 , so that photocharge at the floating diffusion node FD is output to the column driver 117 via the drive transistor Dx. After a predetermined time during which the photocharge is output through the select transistor Sx, the select transistor Sx of each pixel in the first row is turned off and then a reset operation may be performed on the first row. In other words, the reset transistor Rx of each pixel in the first row is turned on by the reset signal RS output from the control unit 112 , so that photocharge remaining in the floating diffusion node FD is eliminated. After a predetermined period of the reset operation, the reset transistor Rx is turned off and then a readout operation may be started with respect to the second row. In addition, photocharge integration may be started with respect to the first row in parallel with the start of the readout operation on the second row. In other words, the transfer transistor Tx of each pixel in the first row is turned on by the transfer control signal TG output from the control unit 112 , so that photocharge generated by the photodiode PD is transferred to the floating diffusion node FD. These readout and reset operations may be repeated with respect to the rows sequentially until the reset operation of the twelfth row is completed. After the reset operation on the n-th row is completed, the light source 120 may be turned off for the first duration t LED1 in operation S 520 . In other words, after the readout and reset operations are completed with respect to the entire first through n-th rows, the light source 120 may be turned off by the control unit 112 . Until a readout operation on each pixel in the first row of the pixel array 140 is started with respect to a subsequent frame, the off state of the light source 120 may be maintained for the first duration t LED1 . The first duration t LED1 is a period of time while the light source 120 is off, and it may be less than or equal to the time t VB . In addition, after the readout and reset operations are completed with respect to all of the first through n-th rows, accumulation of photocharge at the floating diffusion node FD may be stopped in the first through n-th rows of the pixel array 140 for the second duration in operation S 530 . In other words, the transfer transistor Tx of every pixel in the first through n-th rows of the pixel array 140 is simultaneously turned off by the transfer control signal TG output from the control unit 112 , so that photocharge generated by the photodiode PD is blocked from being transferred to the floating diffusion node FD. After the second duration elapses, the transfer transistor Tx is turned on, so that the photocharge resumes to be transferred to the floating diffusion node FD. The second duration refers to a period of time while the photocharge accumulation at the floating diffusion node FD is stopped, and it may be included in the first duration t LED1 . After the first duration t LED1 elapses, readout and reset operations may be performed on the first through n-th rows sequentially in the pixel array 140 in operation S 540 . In other words, after the first duration t LED1 elapses, the light source 120 is turned on, and a readout operation may be performed on each pixel in the first row of the pixel array 140 with respect to the subsequent frame. In detail, the select transistor Sx of each pixel in the first row is turned on by the select signal SEL output from the control unit 112 , so that photocharge at the floating diffusion node FD is output to the column driver 117 via the drive transistor Dx. After the predetermined time during which the photocharge is output through the select transistor Sx, the select transistor Sx of each pixel in the first row is turned off and then a reset operation may be performed on the first row. In other words, the reset transistor Rx of each pixel in the first row is turned on by the reset signal RS output from the control unit 112 , so that photocharge remaining in the floating diffusion node FD is eliminated. After the predetermined period of the reset operation, the reset transistor Rx is turned off and then a readout operation may be started with respect to the second row. In addition, photocharge integration may be started with respect to the first row in parallel with the start of the readout operation on the second row. In other words, the transfer transistor Tx of each pixel in the first row is turned on by the transfer control signal TG output from the control unit 112 , so that photocharge generated by the photodiode PD is transferred to the floating diffusion node FD. These readout and reset operations may be repeated with respect to the rows sequentially until the reset operation of the n-th row is completed. FIG. 6 is a timing chart showing an image sensor control method according to other embodiments of the inventive concept. There are two timing charts in FIG. 6 . The upper one will be referred to as a first timing chart and the lower one will be referred to as a second timing chart. The first timing chart shows an image sensor control method in another comparison example. The second timing chart shows the image sensor control method according to the current embodiments of the inventive concept. Here, t SET denotes a time taken to form a single depth frame. In the image sensor 100 using CMOS-based TOF, four frames are needed to form a single depth frame. In the first timing chart, a time taken to complete a single cycle of readout, reset, and integration on a single row in the pixel array 140 is denoted by t F . In the second timing chart, a time taken to complete a single cycle of readout, reset, and integration on a single row in the pixel array 140 is denoted by t F2 . The pixel array 140 may include first through n-th rows (where “n” is an integer of at least 2). For convenience, it is assumed that “n” is 12 in the FIG. 6 . When the light source 120 is turned off from a time point t OFF to a time point t ON in the first timing chart, this on-off operation of the light source 120 may damage depth information. When it is assumed that there are first through eighth frames from the left to the right, radiation time of light from the light source 120 is irregular with respect to the second through fourth frames during photocharge integration. In particular, most of the rows are not irradiated with the light of the light source 120 during the photocharge integration in the third frame, which may result in serious damage to the depth information (see, e.g., FIG. 6 ( a )). The time t F2 taken to complete a single cycle of readout, reset, and integration on a single row in the pixel array 140 in the second timing chart is regularly reduced as compared to the time t F in the first timing chart. The time t F2 may be adjusted by controlling the timing of the transfer control signal TG applied to the transfer transistor Tx, the reset signal RS applied to the reset transistor Rx, and the select signal SEL applied to the select transistor Sx using the control unit 112 . It is assumed that there are first through eighth frames from the left to the right in the second timing chart. When the time t SET taken to form a single depth frame is maintained constant, if the time t F2 is reduced, a time taken to complete a cycle of readout, reset, and integration with respect to the first through n-th rows of the pixel array 140 up to a fourth frame (i.e., a time taken to form a first depth frame) is less than the time t SET . After a reset operation on the twelfth row is completed in the fourth frame, the light source 120 may be turned off. The light source 120 may be turned on after a third duration t LED3 . After the third duration t LED3 elapses, a readout operation may be performed on the first row in a fifth frame and the readout, reset and integration operations may be performed on the first through twelfth rows sequentially. When the light emission timing of the light source 120 of the image sensor 100 is adjusted as described above, the radiation time of light from the light source 120 is maintained constant between frames during photocharge integration in the second timing chart (i.e., FIG. 6 ( b )) unlike the first timing chart (i.e., FIG. 6 ( a )). Since the time t F2 is shorter than the time t F , the radiation time is shorter in the embodiments illustrated in the second timing chart than in the comparison example illustrated in the first timing chart. However, the shorter radiation may be compensated for by adjusting the luminance of the light source 120 . In the second timing chart, an integration time t INT for a single row is the time t F2 less the time t SR taken to complete the readout and reset operations on a single row. A minimum value t INTMIN of the time t INT is calculated using Equation 1: t INTMIN =( n− 1) t SR .  (1) The readout and reset operations are performed on each row one-at-a time and cannot be performed on a plurality of rows simultaneously. In the first frame, when the reset operation is completed on the first row, an integration time for the first row starts. In parallel with the photocharge integration of the first row, the readout and reset operations are performed on the second through n-th rows sequentially. The readout operation of the first row in the second frame cannot be started before the reset operation of the n-th row is completed. Accordingly, the time t INT needs to be at least a time obtained by multiplying the time t SR by (n−1), that is, a time taken to complete the readout and reset operations with respect to the second through n-th rows. A maximum value t INTMAX of the time t INT is calculated using Equation 2: t INTMAX = 1 4 ⁢ ⁢ FPS D - t SR , ( 2 ) where FPS D is a frame rate of a depth image, that is, the number of frames per second, and a reciprocal for FPS D is a time taken to form a depth frame, i.e., t SET . Consequently, the time t INT has a maximum value when frames are formed as shown in the first timing chart. When a single depth frame is formed of four frames, a value obtained by adding a result of multiplying t INT by 4 and a result of multiplying t SR by 4 is the same as the time t SET , i.e., the reciprocal for FPS D . Equation 2 can be obtained from these formulas. As shown by FIG. 6 , the light source 120 is turned off whenever a depth frame is completed, but the inventive concept is not restricted to the current embodiments. The light source 120 may be turned off every time when at least two depth frames are completed in order to prevent the over-saturation and the under-exposure. FIG. 7 is a flowchart of the image sensor control method illustrated in FIG. 6 . Referring to FIGS. 6 and 7 , readout, reset and integration operations may be performed on the first through n-th rows sequentially in the pixel array 140 at least two times in operation S 710 . At this time, a readout operation on each pixel included in the first row of the pixel array 140 may be performed first. In other words, the select transistor Sx of each pixel in the first row is turned on by the select signal SEL output from the control unit 112 , so that photocharge at the floating diffusion node FD is output to the column driver 117 via the drive transistor Dx. After a predetermined time during which the photocharge is output through the select transistor Sx, the select transistor Sx of each pixel in the first row is turned off and then a reset operation may be performed on the first row. In other words, the reset transistor Rx of each pixel in the first row is turned on by the reset signal RS output from the control unit 112 , so that photocharge remaining in the floating diffusion node FD is eliminated. After a predetermined period of the reset operation, the reset transistor Rx is turned off and then a readout operation may be started with respect to the second row. In addition, photocharge integration may be started with respect to the first row in parallel with the start of the readout operation on the second row. In other words, the transfer transistor Tx of each pixel in the first row is turned on by the transfer control signal TG output from the control unit 112 , so that photocharge generated by the photodiode PD is transferred to the floating diffusion node FD. These readout, reset, and integration operations may be repeated with respect to the rows sequentially until the integration operation of the n-th row is completed. In addition, the readout, reset, and integration operations performed sequentially on the first through n-th rows may be repeated at least two times (which is assumed to be four times in the embodiments illustrated in FIG. 6 ), so that a first depth frame is formed. After the first depth frame is formed, the light source 120 may be turned off for the third duration t LED3 in operation S 720 . In other words, after the readout and reset operations are completed with respect to the entire first through n-th rows, the light source 120 may be turned off by the control unit 112 . Until a readout operation on each pixel in the first row of the pixel array 140 is started with respect to a subsequent frame, the off state of the light source 120 may be maintained for the third duration t LED3 . After the third duration t LED3 elapses, the readout, reset, and integration operations may be performed on the first through n-th rows sequentially in the pixel array 140 at least two times in operation S 730 . Firstly, the readout operation may be performed on each pixel in the first row of the pixel array 140 . In detail, the select transistor Sx of each pixel in the first row is turned on by the select signal SEL output from the control unit 112 , so that photocharge at the floating diffusion node FD is output to the column driver 117 via the drive transistor Dx. After the predetermined time during which the photocharge is output through the select transistor Sx, the select transistor Sx of each pixel in the first row is turned off and then a reset operation may be performed on the first row. In other words, the reset transistor Rx of each pixel in the first row is turned on by the reset signal RS output from the control unit 112 , so that photocharge remaining in the floating diffusion node FD is eliminated. After the predetermined period of the reset operation, the reset transistor Rx is turned off and then a readout operation may be started with respect to the second row. In addition, photocharge integration may be started with respect to the first row in parallel with the start of the readout operation on the second row. In other words, the transfer transistor Tx of each pixel in the first row is turned on by the transfer control signal TG output from the control unit 112 , so that photocharge generated by the photodiode PD is transferred to the floating diffusion node FD. These readout, reset, and integration operations may be repeated with respect to the rows sequentially until the integration operation of the n-th row is completed. In addition, the readout, reset, and integration operations performed sequentially on the first through n-th rows may be repeated at least two times (which is assumed to be four times in the embodiments illustrated in FIG. 6 ), so that a second depth frame is formed. When the operation of the image sensor 100 is controlled as described above, the radiation time of the light from the light source 120 is maintained constant with respect to the first through n-th rows in each frame during photocharge integration of each row. Although the 12 rows exist in the pixel array 140 in the current embodiments illustrated in FIG. 6 , the inventive concept is not restricted thereto. In the image sensor control method according to the current embodiments, the radiation time of light from the light source 120 is the same with respect to the rows in the pixel array 140 and frames during the photocharge integration of each row even if the light source 120 is turned off, so that the quality of images is increased. FIG. 8 is a schematic block diagram of a semiconductor system 800 including the image sensor 100 using an image sensor control method according to some embodiments of the inventive concept. Referring to FIG. 8 , the semiconductor system 800 , e.g., a computer system, may include a bus 810 , a central processing unit (CPU) 820 , the image sensor 100 using the image sensor control method according to some embodiments of the inventive concept, and a memory device 830 . The semiconductor system 800 may also include an interface (not shown), which is connected to the bus 810 and communicate with an outside. Here, the interface may be an input/output interface and may also be a wireless interface. The CPU 820 may generate a control signal for controlling the operation of the image sensor 100 and may apply the control signal to the image sensor 100 via the bus 810 . The memory device 830 may receive distance information or a 3D image signal including the distance information from the image sensor 100 via the bus 810 and store the distance information or the 3D image signal. The image sensor 100 may be integrated with the CPU 820 and the memory device 830 or with a digital signal processor (DSP) into a single chip or may be independently implemented in a separate chip. As described above, according to some embodiments of the inventive concept, even when a light source is turned off in an image sensor, radiation time of light from the light source is constant with respect to rows in a pixel array during photocharge integration of each row, thereby increasing the quality of an image. In addition, the photocharge integration is stopped while the light source is off, thereby preventing an SNR from decreasing. While the inventive concept has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in forms and details may be made therein without departing from the spirit and scope of the inventive concept as defined by the following claims.
An image capture device includes an image sensor having an array of pixels therein, which are configured to receive light reflected from an object during an image capture time interval. A light source is provided, which is configured to project light to the object during at least a portion of the image capture time interval. A control circuit/unit is provided, which is electrically coupled to the image sensor and the light source. This control circuit is configured to drive the light source with signals that cause the light source to project light to the object without interruption during at least a first time interval when all rows of a frame of pixels within the array are being sequentially read and during a second time interval when all rows of the frame of pixels within the array are being sequentially read.
7
BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The present invention relates to a unit carrier for secondary units of a motor vehicle internal combustion engine, having secondary unit attachment devices and engine block attachment devices. The invention also relates to an internal combustion engine for a motor vehicle having at least one secondary unit and one secondary unit carrier. [0003] 2. The Prior Art [0004] A unit carrier for an internal combustion engine, which has secondary unit attachment devices and engine block attachment devices, is known from German Patent No. DE 195 43 350 C1. The unit carrier attaches a generator to the internal combustion engine. The secondary unit carrier is attached to a face of the internal combustion engine, and is formed by the control housing-cover. The secondary unit carrier is reinforced by means of a carrier structure that is arranged in a framework manner between the holders for the secondary units and has cross-ribs and struts connected with them. By means of the arrangement of the cross-ribs and struts, an extremely rigid control housing cover is created, by way of which an introduction of force of the secondary units into the motor housing can take place. SUMMARY OF THE INVENTION [0005] It is therefore an object of the invention to improve the crash behavior of motor vehicles. According to the invention, a unit carrier for secondary units of a motor vehicle internal combustion engine, having secondary unit attachment devices and engine block attachment devices, is provided. The unit carrier has a planned deformation point which allows a relative displacement between the secondary unit and the engine block in case of a vehicle collision, if a pre-defined force on a secondary unit is exceeded. [0006] By providing a planned deformation point, a block formation of secondary units and engine block in case of a crash is avoided, and the risk of penetration of the engine block into the passenger compartment of the motor vehicle is reduced. In this connection, block formation refers to the behavior of the engine with the secondary units as a single, rigid structure, which is displaced as a whole in case of a crash, without absorbing any impact energy. With the unit carrier according to the invention, in case of a crash, the engine block and secondary units can be displaced, relative to one another. This increases the deformation possibilities of a motor vehicle and, in case of a crash, more energy can be absorbed by car body parts or other components, by avoiding the block formation. [0007] In one embodiment of the invention, the planned deformation point is formed between the secondary unit attachment devices and the engine block attachment devices. [0008] In this manner, the planned deformation point can be formed independent of the configuration of the secondary unit attachment devices and the engine block attachment devices. This facilities the use of conventional secondary units and conventional engine blocks. Furthermore, in the case of a less severe vehicle collision, it can be assured that the secondary units and the engine block remain essentially undamaged, and merely the unit carrier has to be replaced. [0009] In addition, the planned deformation point is preferably configured as a planned breakage point. By means of these measures, part of the impact energy can be dissipated by having the unit carrier shear off at planned breakage points provided for this purpose, and a great displacement between the secondary unit and the engine block is made possible by having the unit carrier shear off. In this case, the secondary unit can be prevented from freely flying around, for example by additionally securing the secondary unit with a strap, or by securing the secondary unit with the drive belt or a drive chain, which is provided in any case. [0010] In a further development of the invention, the planned deformation point is configured such that in case of a vehicle collision, controlled deformation of the planned deformation point and dissipation of impact energy takes place, with a relative displacement between the secondary unit and the engine block. In this manner, the unit carrier can support controlled energy dissipation in case of a collision. [0011] The invention also includes an internal combustion engine having at least one secondary unit and one secondary unit carrier, wherein a front delimitation of the unit carrier and/or the at least one secondary unit lies in front, relative to a front delimitation of the engine block, seen in a collision direction to be expected here. [0012] By means of such target placement of the unit carrier and/or the secondary units in front, early contact of the combination of engine block and secondary units with the other party in the accident is produced. In this manner, the internal combustion engine can participate in the delay at an earlier point in time, and dissipation of energy can take place via displacement of the entire internal combustion engine, or also by means of a deformation of the unit carrier. In this connection, the planned deformation point of the unit carrier can be designed in different ways, so that either the unit carrier is deformed or shears off before any displacement of the engine block, or the unit carrier is deformed or shears off only after displacement of the engine block and a further increase in forces. In each case, block formation of the engine block and secondary units during the collision is avoided, and the risk of penetration of the engine block into the interior is reduced. Because energy also can be dissipated by the unit carrier according to the invention during a collision, the surrounding car body parts can be designed to be lighter, for example, since they no longer have to absorb the complete impact energy. BRIEF DESCRIPTION OF THE DRAWINGS [0013] Other objects and features of the present invention will become apparent from the following detailed description considered in connection with the accompanying drawings. It is to be understood, however, that the drawings are designed as an illustration only and not as a definition of the limits of the invention. [0014] In the drawings, wherein similar reference characters denote similar elements throughout the several views: [0015] FIG. 1 shows a schematic top view of an internal combustion engine according to the invention, in the installed state, with a unit carrier; and [0016] FIG. 2 shows a schematic representation of the internal combustion engine of FIG. 1 , after a vehicle collision. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT [0017] Referring now in detail to the drawings, FIG. 1 schematically shows an internal combustion engine 10 having an engine block 12 , which is connected with a motor vehicle by two engine bearings 14 . A forward travel direction of the motor vehicle is indicated by arrow 16 . Opposite forward travel direction 16 , a clutch bell 18 and a transmission 20 follow engine block 12 . The internal combustion engine 10 is arranged in an engine space (not shown) of the motor vehicle. Bearing points 15 that are fixed on the car body are indicated, and a rear delimitation of the engine space is represented by the indicated contour 22 of a water tank. Opposite the forward travel direction 16 , a vehicle interior follows contour 22 of the water tank. [0018] Seen in the forward travel direction 16 , a unit carrier 24 is attached to one face of engine block 12 , with several secondary units attached to this carrier, for example a generator 26 and a refrigerant compressor 28 . Generator 26 and refrigerant compressor 28 are driven by a drive belt 30 , which in turn is driven by a pulley arranged on a crankshaft continuation 32 . [0019] Seen in forward travel direction 16 , a radiator 34 follows drive belt 30 , and a front delimitation of the motor vehicle is formed by a front part structure, indicated schematically. [0020] Unit carrier 24 is configured so that the secondary units, namely generator 26 and refrigerant compressor 28 , seen in the forward travel direction 16 , are arranged on the side, next to engine block 12 . In this connection, both generator 26 and refrigerant compressor 28 are arranged at a distance from engine block 12 , by means of the unit carrier 24 , so that a relative movement of generator 26 and refrigerant compressor 28 , relative to engine block 12 , is possible in case of a crash, as will be explained in more detail below. Unit carrier 24 is provided with two planned breakage points 38 that are merely indicated schematically in FIG. 1 , by means of a notch. Planned breakage points 38 are arranged approximately at the level of the lateral delimitations of engine block 12 , seen in the forward travel direction 16 . As will be described below, unit carrier 24 can thereby shear off in the region of planned breakage points 38 , and generator 26 and/or refrigerant compressor 28 can be displaced opposite travel direction 16 , together with the broken piece of unit carrier 24 that is attached to them. [0021] Unit carrier 24 is furthermore configured so that seen in forward travel direction 16 , a front delimitation of the secondary units, namely generator 26 and refrigerant compressor 28 , is located in front, relative to a front delimitation of engine block 12 . A front delimitation of generator 26 or refrigerant compressor 28 is formed by a pulley, in each instance, by way of which drive belt 30 runs and drives a shaft of generator 26 or refrigerant compressor 28 , in each instance. In the representation according to FIG. 1 , the front delimitation of generator 26 and refrigerant compressor 28 is placed in front of engine block 12 , proceeding from the front delimitation of the latter, by approximately a quarter of its length, in the forward travel direction 16 . In this connection, the forward placement is chosen to be so great that a noteworthy dissipation of energy can already take place by means of unit carrier 24 deforming or shearing off in case of a collision. Because of the energy dissipation by unit carrier 24 , the surrounding car body parts can therefore be relieved of stress in case of a collision, and can be made lighter, if necessary. [0022] The schematic representation of FIG. 2 shows the internal combustion engine 10 of FIG. 1 after a vehicle collision. Here, the front part structure 36 has been displaced by a deformation path A opposite forward travel direction 16 . The original position of front part structure 36 and radiator 34 is indicated by dot-dash lines in FIG. 2 . [0023] As a result of the displacement of front part structure 36 by deformation path A, engine block 12 has also been displaced towards the vehicle interior, by a (smaller) distance. This can be seen, for example, by the position of the motor bearings 14 relative to the fixed bearing points 15 on the car body, which has been displaced towards the rear in FIG. 2 , as well as by the position of engine block 12 , clutch bell 18 , and transmission 20 , which position has been displaced relative to contour 22 of the water tank. [0024] In FIG. 2 , unit carrier 24 has sheared off in the region of its two planned breakage points 38 , so that both generator 26 and refrigerant compressor 28 were able to be displaced, seen opposite the forward travel direction 16 . In this connection, both generator 26 and refrigerant compressor 28 have not only been displaced opposite forward travel direction 16 , but have also performed a rotational movement, approximately about the center of unit carrier 24 . In FIG. 2 , generator 26 and refrigerant compressor 28 are now only connected with engine block 12 by way of drive belt 30 . Guidance of drive belt 30 on generator 26 and refrigerant compressor 28 , respectively, can be implemented in such a way that generator 26 and refrigerant compressor 28 , respectively, with the broken piece of unit carrier 24 attached to them, are prevented from flying around. As an alternative, unit carrier 24 can be configured so that instead of a planned breakage point, a planned deformation point is provided, and even after a vehicle collision, the secondary units are securely held on engine block 12 , by means of unit carrier 24 , which is then deformed. [0025] In total, it is evident from FIGS. 1 and 2 that because of the forward placement of generator 26 and refrigerant compressor 28 , relative to engine block 12 , the internal combustion engine 10 can already participate in a collision delay at an early point in time, and that energy dissipation by means of deformation of unit carrier 24 can already take place at an early point in time during the collision, because the secondary units are placed in front and because planned breakage points 38 are provided on unit carrier 24 . Furthermore, by providing planned breakage points 38 on unit carrier 24 , block formation of engine block 12 and generator 26 as well as the refrigerant compressor 28 is avoided, so that compared with the total deformation path A, a relatively low penetration depth of internal combustion engine 10 in the direction of the vehicle interior occurs. [0026] Accordingly, while only a few embodiments of the present invention have been shown and described, it is obvious that many changes and modifications may be made thereunto without departing from the spirit and scope of the invention.
A unit carrier for secondary units of a motor vehicle internal combustion engine, having secondary unit attachment devices and engine block attachment devices. The unit carrier has a planned deformation point, which allows a relative displacement between the secondary unit and the engine block in case of a vehicle collision, if a predefined force is exceeded. The unit carrier is used in motor vehicles having a front engine arrangement.
5
BACKGROUND OF THE INVENTION The invention relates to an automatic adjustment device for a mechanically actuated disk brake, including a sliding saddle that moves on a diagonal relative to the brake disk and whose two saddle halves, each has a brake lining support and a brake lining, cover the brake disk, an actuating shaft that has a rotating mount in one of the saddle halves, the bushed end of which exhibits a radially projecting collar, one side of which is furnished with diagonal tracks for the reception of balls, which tracks correspond to diagonal tracks on a bearing ring and serve to convert the rotational motion of the actuating shaft into the axial motion of a pressure screw which is mounted in torque-resistant fashion to a piston, while the actuating shaft is supported by an axial bearing on the sliding saddle to secure it against axial displacement on the side of the collar facing away from the diagonal tracks, and the bearing ring is capable of axial motion relative to the brake saddle, but is secured against rotation, and is supported by a sleeve-like adjustment nut into which the pressure screw is screwed and which is attached in torque-resistant fashion to an extension piece which coaxially passes through the actuating shaft. An adjustment ring is rotationally mounted relative to the extension piece, the adjustment ring or the actuating shaft having a radial pin that engages in a groove of the actuating shaft or of the adjustment ring. An adjustment sleeve is positioned on the extension piece, the adjustment ring and the adjustment sleeve having spiral gearings on their facing sides, and one of the two adjustment parts having a spiral gearing supported by a collar of the adjustment nut. A spring component is supported on the other adjustment part in order to maintain the engagement of the two spiral gearings, a directional clutch is positioned in the power flow from the adjustment ring to the adjustment nut and takes effect in the direction of brake actuation upon rotation of the actuating shaft, and a torque limiting device limits the torque that can be transferred from the adjustment ring to the adjustment nut. An adjustment device of this type described in German Patent Document DE-OS 38 14 475 employs a movable saw-tooth catch to adjust the wear on brake linings by stages. The clearing play is thus determined by the selected tooth spacing. Reducing the clearing play with a very small spacing is impossible for manufacturing reasons, however. Thus in overcoming the clearing play, a correspondingly large actuation stroke (return stroke) is necessary for brake actuation, and a reduction in the actuation path reserve may also be evident. The size of the actuating stroke, however, is also determined by the incline of the diagonal tracks on the bearing ring and on the actuating shaft. A small incline demands a relatively large actuating stroke to provide the necessary spread. An increase in the incline, which results in a more rapid positioning of the brake shoe on the brake disk when the actuating stroke is reduced, requires larger actuating cylinders to achieve the same braking effect, due to reduced transmission. In actual practice the object is to reduce the actuation stroke by means of a minimal return stroke and a clearing play that approaches zero, in order to thereby achieve a more rapid contact of the brake shoe with the brake disk and ultimately to increase the actuation reserve for emergency and complete braking. This requirement is primarily an objective when disk brakes of the given type are to be effectively employed in ABS (antilocking system) braking apparatus, i.e. reduced air consumption per braking action, faster filling times for the actuation cylinders, and thus shorter pressure buildup times for the overall brake apparatus. Given an equal total transmission for the actuating mechanism, faster brake lining contact is achieved due to shorter return strokes. This requirement can only be fulfilled by a continuously adjustable regulating device, which also operates in a force-dependent manner. In addition, the inventive adjustment device must provide a noticeable simplification vis-a-vis the state of the art, with a reduction of the number of necessary adjustment parts. The adjustment device of the invention must also make possible a simpler reset procedure, while both eliminating chatter upon rapid skipping of the spiral gearing and avoiding the use of a clearance ring for the frictional connection, inasmuch as such rings make resetting more difficult due to fluctuations in the frictional value. BRIEF SUMMARY OF THE INVENTION This problem is solved by the invention in that the adjustment sleeve is mounted in rotating fashion on the extension piece of the adjustment nut and is supported by a collar on the adjustment nut; the adjustment sleeve is connected with the adjustment nut by means of an adjustment clutch; the groove in the adjustment ring or in the actuating shaft is an axial groove; and the spiral gearings positioned on the faces of the adjustment sleeve and the adjustment ring permit reciprocal skipping in the direction of brake actuation while the spring component is compressed. BRIEF DESCRIPTION OF THE DRAWINGS Several, embodiments of the invention will now be described in detail with reference to the accompanying drawing wherein: FIG. 1 is an axially cross-sectional view through a sliding saddle disk brake of the invention; FIG. 2 is a cross-sectional view taken along line II--II in FIG. 1; FIG. 3 is a view similar to that of FIG. 1 through a modified embodiment of the invention; FIG. 4 is a cross-sectional view taken along line IV--IV in FIG. 3; and FIG. 5 is a view similar to that of FIG. 1 through another embodiment of the invention. DETAILED DESCRIPTION As can be seen from the drawing, the depicted sliding saddle disk brake comprises a sliding saddle 1, whose two saddle halves 4 and 5 cover the brake disk 6, which is indicated by broken lines. The two saddle halves each have a brake lining support 2, which supports a brake lining 3 facing the brake disk 6. In saddle half 5 of the sliding saddle 1 an actuating shaft 7 is rotationally mounted by means of a lever (not shown). Actuating shaft 7 has an inner end in the form of a bushing with a radially projecting collar 9. On its side facing away from the lever collar 9 is provided with at least two, preferably three, diagonal tracks 10 to receive balls 11, which, on the other side, run in corresponding diagonal tracks 12 on a bearing ring 13. Relative to each other, the corresponding tracks 10 and 12 are positioned on collar 9 and bearing ring 13 in such a way that rotation of the actuating shaft 7 is converted into axial motion of the bearing ring 13 and an adjustment nut 14 supported therein. Screwed into this adjustment nut 14 is a pressure screw 15, which is attached to the piston 21 in torque-resistant fashion, while the piston 21 is prevented from rotation. In order to translate axial forces from the bearing ring 13 to the adjustment nut 14, the latter is furnished with a radially projecting shoulder 17, which engages with bearing ring 13. In order that the bearing ring 13 can be axially displaced by the actuating shaft without participating in the rotation of the actuating shaft 7, rotation is prevented by an axially parallel guide groove 18, which is engaged by a guide pin 19 also passing through the piston 21 in a groove 22. This guide pin 19 is formed by the projecting front end of a screw bolt 20 screwed into a threaded bore 20' in the sliding saddle 1. A ring collar 26 of elastic plastic, which extends from the sliding saddle 1 to the piston 21, protects the actuating mechanism from penetration by foreign bodies, dirt and moisture. On the back side of the collar 9 in a direction opposite from the diagonal tracks 10, an axial bearing 27 is provided that supports actuating shaft 7 on the sliding saddle 1. The adjustment nut 14 is connected with an extension piece 24 in torsionally reinforced fashion. Rotationally mounted on the extension piece 24 are an adjustment sleeve 28 and an adjustment ring 29, whose facing sides have a spiral gearing 30. The two adjustment parts 28 and 29 are held in position by a compression spring 23 supported by extension piece 24, since the adjustment sleeve 28 rests against the heel of the adjustment nut 14. The spiral gearing 30 could be replaced by a frictionally engaged coupler. Preferably, however, a very small spiral gearing will be employed, since frictional couplers tend to undesirably separate as a result of vibration or shaking. A pin 32 secured to the actuating shaft 7 engages with an axial groove 31 of the adjustment ring 29 (see FIG. 2). The play L here represents the clearing play. The play can be eliminated, however, if the very low degree of play that is desired can be achieved by the production tolerances of the brake parts alone. By means of another pressure spring 25, which is supported both by the actuating shaft 7 and the extension piece 24 of the adjustment nut 14, shoulder 17 of adjustment nut 14 is brought into contact with the bearing ring 13, and the spreading device 9, 11, 13 is held in position on the ball guides 10, 12 without play. On the circumferential area of the adjustment nut 14 and the adjustment sleeve 28, positioned at either side of and resting on a collar, is a wrap spring 33 connecting both of these parts. With its cylindrically wound spring component this radially tensioned wrap spring 33 rests on the circumferential areas of the adjustment parts 14, 28 and forms a directional clutch. When the brake is actuated, this directional clutch transfers torque from the adjustment sleeve 28 to the adjustment nut 14, and when the brake is released it slips through like a freewheel. The secondary, force-dependent connection is produced by the spiral gearing 30 or, alternatively, by a frictional coupling between the adjustment part 28 and 29. The force-dependent adjustment process operates as follows: When the actuating shaft 7 is set in motion by braking in the direction of the arrow, its pin 32, which engages the axial groove 31 of the adjustment ring 29 without play or with play L and which employs the tension exerted by the pressure spring 23, turns the adjustment sleeve 28 by means of the spiral gearings 30 or by means of a frictional coupling. This motion of the adjustment parts 28, 29 is immediately transmitted by the wrap spring 33 to the adjustment nut 14. The torque is greater than the frictional moment, arising via the second pressure spring 25, between the shoulder 17 of the adjustment nut 14 and the bearing ring 13. The clearing play is adjusted by rotation of the adjustment nut 14 against the pressure screw 15. As soon as the brake linings 3 come into contact with the brake disk 6, the tension-induced friction between the shoulder 17 and the bearing ring 13 increases and therewith exceeds the torque that can be transferred by the spiral gearings 30. When the actuating shaft 7 further rotates in the direction of actuation, the adjustment nut 14 is held in place by the sharply increasing frictional moment on the bearing ring 13, and the adjustment ring 28 slips through against the force exerted by pressure spring 23 by means of the force-dependent spiral gearing 30 or a frictional connection with the adjustment sleeve 28, and further adjustment is prevented. The portion of the actuation path traveled under brake tension, which results in an elastic deformation of the brake, is thus not taken into account by the adjustment. When the brake is released the force of the pressure spring 23 presses the adjustment parts 28, 29 together, and as a result of the releasing motion of the actuating shaft 7, the pin 32 turns back these parts 28, 29, according to the wear on the brake linings. The adjustment nut 14 is not turned back as well, since it is held in position on the bearing ring 13 by a second pressure spring 25 and since the wrap spring 33 works as a freewheel during the release motion. In the subsequent brake action, lining wear is again adjusted in the manner described. The release action necessary when the brake linings are replaced and a new initial adjustment is set is very simple. A wrench is employed to grasp the extension piece 24 and to turn back the adjustment nut 14 in the locking direction of the wrap spring 33, while the gears of the spiral gearing 30 skip over each other. In the embodiment shown in FIGS. 1 and 2, it is possible that under certain circumstances--e.g. hardened grease resulting from low temperatures--an excessive degree of adhesive friction will arise between the contact surfaces 38 of the adjustment nut 14 and the adjustment sleeve 28, due to the tension force of the pressure spring 23. The result may be that after brake actuation, i.e. when the actuating shaft 7 returns to its starting position after the brake is released and as the result of the above-mention adhesive friction, the adjustment nut--despite the neutral direction of the one-way couplings 33 or 34--will be turned back unintentionally with the adjustment parts 28 and 29, thus negating the preceding adjustment performed during brake actuation. To avoid this, the adhesive friction, caused by the force exerted by the pressure spring 25, between the contact surfaces of parts 13, 17 must be greater than the adhesive friction between parts 14 and 28 produced by the pressure spring 23. In order to completely eliminate the axial adhesive friction between the contact surfaces 38 of parts 14, 28, which causes the undesirable return of the adjustment nut 14 after brake actuation, the elaboration shown in FIGS. 3 and 5 is provided. In this preferred embodiment, the adjustment sleeve 28 is provided with an extension, on which the turning and axially sliding adjustment ring 29 rests. The latter is acted on by compression spring 23, which in turn is supported by the extension of the adjustment sleeve 28 by means of an annular disk on the securing ring 36. The spiral gearing 30 of the force-dependent clutch is thereby kept in engaged state. The adjustment sleeve 28 itself is positioned by a fixed heel or retaining ring 37 on the extension piece to prevent axial displacement on the extension piece 24 of the adjustment nut 14. Thus the adjustment sleeve 28 is held in its position between the contact surface 38 of the adjustment nut 14 and the fixed heel 37, without spring action but with little play. The axial adhesive friction between parts 14 and 28 explained above and resulting from spring-induced force is thereby eliminated. After brake actuation is complete, thus in the direction of brake release, the adjustment parts 28 and 29 can be turned with the actuating shaft 7 in the freewheel direction of the one-way clutch 33, without the adjustment nut 14 being undesirably entrained in the same direction. The modified embodiment shown in FIG. 5 omits the wrap spring 33, which acts as a directional clutch for the transfer of torque between the adjustment nut 14 and the adjustment sleeve 28. In this variation, the role and function of the wrap spring 33 is replaced by the use of a sleeve freewheel 34, which likewise serves as a directional clutch for the transfer of torque between the adjustment nut 14 and the adjustment sleeve 28. Here the outer ring 35 of the freewheeling sleeve 34 rests on the inner circumference of the adjustment sleeve 28, and the inner ring of the freewheeling sleeve 34 rests with its roller bearing on the external circumference of the extension piece 24 of the adjustment nut 14. This embodiment also guarantees that adhesive friction between the adjustment sleeve 28 and the adjustment nut 14 does not arise. To this end, the adjustment ring 29 rests on a sleeve 39. The latter has two end collars which extend outward radially; the one collar 40 interlocks with a collar of the adjustment sleeve 28 extending radially inward, and the other collar 41 serves as a support for the pressure spring 23 and as an attachment to the fixed heel 37. To be sure, the adjustment parts 28 and 29 are thereby braced one relative to the other, but there is no axial adhesive friction between the adjustment parts and the adjustment nut 14 as caused by the pressure spring 23.
A continuous automatic adjustment device for a mechanically actuated sliding saddle disk brake (1, 2, 3, 4, 5, 6) wherein the mechanically actuated device for moving the sliding saddle (1) vis-a-vis the brake disk (6) includes a diagonal-track spreading device (10, 11, 12) around an actuating shaft (7). The adjustment device has an adjustment nut (14) coupled with the actuating shaft (7) by a directional clutch (33) which operates in the direction of actuation when actuating shaft (7) turns and is formed by a wrap spring (33) or a freewheeling sleeve (34, 35). A force-dependent coupler (30) can be axially released from the action of a compression spring (23) when a given torque is exceeded by the actuation shaft, thereby preventing rotation from being transmitted to the adjustment nut.
5
CLAIM FOR PRIORITY This application claims priority to German Application No. 10 2004 020 297.4 filed Apr. 26, 2004, which is incorporated herein, in its entirety, by reference. TECHNICAL FIELD OF THE INVENTION The invention relates to a method for manufacturing a resistively switching memory cell, and to a memory device, in particular a resistively switching memory device, and a system including such a memory device. BACKGROUND OF THE INVENTION In the case of conventional memory devices, in particular conventional semiconductor memory devices, one differentiates between so-called functional memory devices (e.g. PLAs, PALs, etc.) and so-called table memory devices, e.g. ROM devices (ROM=Read Only Memory)—in particular PROMs, EPROMs, EEPROMs, flash memories, etc.—, and RAM devices (RAM=Random Access Memory or read-write memory), e.g. DRAMs (Dynamic Random Access Memory or dynamic read-write-memory) and SRAMs (Static Random Access Memory or static read-write-memory). A RAM device is a memory for storing data under a predetermined address and for reading out the data under this address later. Since it is intended to accommodate as many memory cells as possible in a RAM device, one has been trying to realize same as simple as possible and to scale them as small as possible. In the case of SRAMs, the individual memory cells consist e.g. of few, for instance 6, transistors, and in the case of so-called DRAMs in general only of one single, correspondingly controlled capacitive element, e.g. a trench capacitor with the capacitance of which one bit each can be stored as charge. This charge, however, remains for a short time only. Therefore, a so-called “refresh” must be performed regularly, e.g. approximately every 64 ms. In contrast to that, no “refresh” has to be performed in the case of SRAMS since the data stored in the memory cell remain stored as long as an appropriate supply voltage is fed to the SRAM. In the case of non-volatile memory devices (NVMs), e.g. EPROMs, EEPROMs, and flash memories, the stored data remain, however, stored even when the supply voltage is switched off. Furthermore, so-called resistive or resistively switching memory devices have also become known recently, e.g. so-called Phase Change Memories and PMC memories (PMC=Programmable Metallization Cell), which are also referred to as CBRAM memories (CB=Conductive Bridging). In the case of resistive or resistively switching memory devices, an “active” material—which is, for instance, positioned between two appropriate electrodes (i.e. an anode and a cathode)—is placed, by appropriate switching processes, i.e. by appropriate current or voltage pulses of particular intensity and duration, in a more or less conductive state. The more conductive state corresponds e.g. to a stored, logic “One”, and the less conductive state to a stored, logic “Zero”, or vice versa. In the case of Phase Change Memories (PC memories), for instance, a chalcogenide compound may be used as an active material that is positioned between two electrodes. Chalcogenide compounds are e.g. a Ge—Sb—Te or an Ag—In—Sb—Te compound. The chalcogenide compound material has the property to be adapted to be placed in an amorphous, relatively weakly conductive, or a crystalline, relatively strongly conductive state by appropriate switching processes. The relatively strongly conductive state may, for instance, correspond to a stored, logic “One”, and the relatively weakly conductive state may correspond to a stored, logic “Zero”, or vice versa. Phase Change Memory Cells are, for instance, known from G. Wicker, Nonvolatile, High Density, High Performance Phase Change Memory, SPIE Conference on Electronics and Structures for MEMS, Vol. 3891, Queensland, 2, 1999, and e.g. from Y. N. Hwang et al., Completely CMOS Compatible Phase Change Non-volatile RAM Using NMOS Cell Transistors, IEEE Proceedings of the Nonvolatile Semiconductor Memory Workshop, Monterey, 91, 2003, S. Lai et al., OUM-a 180 nm nonvolatile memory cell element technology for stand alone and embedded applications, IEDM 2001, etc. In the case of PMC memories (PMC=Programmable Metallization Cell)—depending on whether a logic “One” or a logic “Zero” is to be written into the cell—conductive bridges (e.g. of Ag or Cu, etc.) are built up during the programming of a corresponding PMC memory cell by means of current or voltage pulses of particular duration and intensity, and by electrochemical reactions caused thereby, in an active material positioned between two electrodes, which results in a conductive state of the cell, or are broken down again, which results in a non-conductive state of the cell. PMC memory cells or CBRAM memory cells, respectively, are e.g. known from Y. Hirose, H. Hirose, J. Appl. Phys. 47, 2767 (1975), and e.g. from M. N. Kozicki, M. Yun, L. Hilt, A. Singh, Electrochemical Society Proc., Vol. 99-13, (1999) 298, M. N. Kozicki, M. Yun, S. J. Yang, J. P. Aberouette, J. P. Bird, Superlattices and Microstructures, Vol. 27, No. 5/6 (2000) 485-488, and e.g. from M. N. Kozicki, M. Mitkova, J. Zhu, M. Park, C. Gopalan, “Can Solid State Electrochemistry Eliminate the Memory Scaling Quandry”, Proc. VLSI (2002) and R. Neale: “Micron to look again at non-volatile amorphous memory”, Electronic Engineering Design (2002). CBRAM memories are, for instance, described in Y. Hirose, H. Hirose, J. Appl. Phys. 47, 2767 (1975), T. Kawaguchi et al., “Optical, electrical and structural properties of amorphous Ag—Ge—S and Ag—Ge—Se films and comparison of photo-induced and thermally induced phenomena of both systems”, J. Appl. Phys. 79 (12), 9096, 1996, and e.g. in M. Kawasaki et al., “Ionic conductivity of Agx(GeSe3)1−x (0<x0.571) glasses”, Solid State Ionics 123, 259, 1999, etc. In the case of CBRAM memory cells, an electro-chemically active material is positioned in a volume between two electrodes, for instance, an appropriate chalcogenide material e.g. in a GeSe, GeS, AgSe, or CuS compound. In the case of the CBRAM memory cell, the above-mentioned switching process is based on the fact that, by applying appropriate current or voltage pulses of particular intensity and duration to the electrodes, elements of a so-called deposition cluster increase in volume in the active material positioned between the electrodes until the two electrodes are finally bridged electroconductively, i.e. are electroconductively connected with each other, which corresponds to the electroconductive state of the CBRAM cell. By applying correspondingly inverse current or voltage pulses, this process can be reversed again, and the corresponding CBRAM cell can be placed in a non-conductive state again. This way, a “switching” between a state with a higher electroconductivity of the CBRAM memory cell and a state with a lower electroconductivity of the CBRAM memory cell can be achieved. The switching process in the CBRAM memory cell is substantially based on the modulation of the chemical composition and the local nanostructure of a chalcogenide material doped with a metal, serving as solid body electrolyte and diffusion matrix. The pure chalcogenide material typically has a semiconductor behavior and has a very high electric resistance at room temperature, the resistance being by magnitudes, i.e. decimal powers of the ohmic resistance value, higher than that of an electroconductive material. By the current or voltage pulses applied via the electrodes, the steric arrangement and the local concentration of the ionically and metallically available components of the element mobile in the diffusion matrix is changed. By that, the so-called bridging, i.e. an electric bridging of the volume between the electrodes of metal-rich depositions, can be caused, which changes the electric resistance of the CBRAM cell by several magnitudes by the ohmic resistance value being decreased by several decimal powers. One difficulty with this switching process in a CBRAM memory cell consists in that the electric resistance between the electrodes may vary relatively strongly with a particular state of the cell (“conductive” or “non-conductive”). This variation aggravates the evaluation or the differentiation, respectively, between the conductive and the non-conductive state by a corresponding evaluation circuit. This means that it is aggravated to determine whether a logic “Zero” or a logic “One” was last stored in the corresponding memory cell. A further difficulty consists in that the CBRAM memory cell does not comprise any reproducible switching properties in the “unconditioned” state. It is therefore necessary to condition the memory cell, i.e. to be able to exactly control the doping of the memory cell, to achieve a reproducible switching behavior. The CBRAM memory cell therefore has to be conditioned prior to the above-described switching behavior. This means that the doping of the chalcogenide matrix positioned between the electrodes has to be adjusted reproducibly by a mobile, metallic element so as to achieve a good control of the overall concentration or a good controllability of the metal element, respectively, and thus a good control of the electric resistance in the CBRAM memory cell. The conditioning of a CBRAM memory cell has so far been performed e.g. by means of photo diffusion, i.e. a probe that may, for instance, be generated by a metal layer on a chalcogenide material is exposed with light in the ultraviolet frequency range, this causing the metal to be driven into the probe. In literature, this method is also referred to as photo diffusion and results in a particular metallic doping profile of the chalcogenide material in which metal-rich depositions form in the chalcogenide matrix. This way, a doped and an undoped phase will be generated in the chalcogenide layer. Other methods by means of which a conditioning of the probe is achieved are, for instance, thermal methods where a regular diffusion occurs, or implantation methods. These methods may also be combined to obtain a doping of the chalcogenide matrix. A drawback of the thermal method consists in that the amorphicity of the probe may be lost since a nanocrystallization with subsequent grain growth occurs which substantially changes the nanostructure or microstructure, respectively, of the probe. The ion movability of the metal doping substance is, however, as a rule by magnitudes smaller in crystalline materials, which may involve a significant degradation of the memory cell properties. A drawback of the photo diffusion process consists i.a. in that the doping profile is very steep due to the photo-stimulated doping process since the movability of the ions is distinctly higher in the metal-rich phase. This results in an extremely critical process control since, as soon as the steep doping edge of the photo diffusion profile at the limiting area has reached the opposite electrode, the memory cell is irreversibly electrically short-circuited. If, however, the photo diffusion profile does not expand far enough through the chalcogenide matrix, an electric forming pulse is additionally required which drives the metallic material thermally into the chalcogenide material by means of local heating. The electric forming pulse is, however, incompatible with some semiconductor manufacturing processes of mass products since an electrical conditioning does not guarantee sufficient reproducibility. A drawback of the implantation process consists in that extremely high doses of metal have to be implanted, which requires a very high implantation performance and/or a very long duration of the implantation process. A further difficulty results from the fact that the implanted doping courses are formed very flatly since otherwise an undesired mixing or, in the case of too deep implantation profile courses, an electric short-circuit will be caused. SUMMARY OF THE INVENTION The present invention provides a method that enables a reproducible conditioning during the manufacturing of a CBRAM memory cell, and a system with such a memory device. The present invention includes, in particular, providing a method by which it is possible to control the diffusion of the ions in the chalcogenide material of the CBRAM memory cell and to thus optimize the concentration profile between the doped and the undoped phase of the chalcogenide matrix. In accordance with one embodiment of the invention, there is provided a method for manufacturing a memory cell, in particular a resistively switching memory cell, comprising a first electrode and a second electrode with an active material positioned therebetween, the active material being adapted to be placed in a more or less electroconductive state by means of electrochemical switching processes, wherein the method comprises: (a) doping the active material in a doping process by diffusing a mobile material into the active material from the first electrode in the direction of the second electrode, (b) optimizing the doping of the active material in a retraction process by at least partial retraction of the mobile material diffused into the active material from a region close to the second electrode. This way, the mobile material is, in the first part of the method, the doping process (a), diffused from the first electrode into the active material, wherein the doping process may be performed until the mobile material has completely diffused through the active material and has reached the second electrode. In the second part of the method, the retraction process (b), the mobile material is diffused back at least partially in the direction from the second electrode to the first electrode, so that the region close to the second electrode assumes an undoped state again. By that, the region close to the second electrode, and thus the memory cell altogether, is conditioned, i.e. the doping of the memory cell can be controlled exactly, which constitutes a prerequisite of a reproducible switching behavior of the memory cell. The active material preferably consists of a chalcogenide compound, in particular a GeSe, GeS, AgSe, CuS, Ge—Sb—Te or an Ag—In—Sb—Te compound, forming a chalcogenide matrix in which the mobile material may move or be diffused into, respectively. The mobile material includes, for example, of alkali ions or metal ions, respectively, in particular of Ag or Cu. The above-mentioned is consequently addressed by the present invention in that the ions that have been diffused too deeply into the chalcogenide matrix diffuse back again at least partially by means of the ion retraction process according to the invention, so that there is the possibility of controlling and thus optimizing the concentration profile between the doped and the undoped region in the chalcogenide layer. The present invention thus provides a method in which the penetration depth of the metal ions into the chalcogenide material may be reduced again during the so-called front end of line processing. According to the present invention, there result new possibilities of process control for the manufacturing of CBRAM memory cells. According to a preferred embodiment of the method according to the invention, a temporary overdoping of the chalcogenide matrix is, for instance, possible by means of an overdoping process, and can be reversed again in the further course of the process. According to another preferred embodiment of the present invention, the above-mentioned doping process (a) is therefore divided into the following partial steps: (a1) doping the active material by diffusing a mobile material into the active material in a doping process, (a2) overdoping the active material by diffusing the mobile material into the active material in an overdoping process exceeding method step (a1), so that a doped region from the first electrode to the second electrode is formed in the active material. The process flow can be substantially simplified in that self-adjusting processes are employed with the method according to the invention. Self-adjusting means in this context that different lithography levels or lithography processes, respectively, do not comprise any misadjustment with respect to one another. Due to the self-adjusting processes, the area of the memory cell can be reduced distinctly, and thus the dimension of the CBRAM memory cell itself can be reduced. Advantageously, the active material is positioned between two electrodes, and the doping process (a or a1, respectively) and/or the overdoping process (a2) is performed such that the mobile material is diffused into the active material from the one electrode to the other electrode. This way, a doped or overdoped phase, respectively, and an undoped phase is formed in the active material or in the chalcogenide matrix, respectively, wherein a particular penetration depth of the mobile material into the active material or the metal ions, respectively, in particular in a region between the doped or over-doped phase, respectively, and the undoped phase in the active material is obtained. Furthermore, by means of the method according to the invention, in the active material or in the chalcogenide matrix, respectively there can be formed a particular concentration profile of the mobile material or the metal ions, respectively, in particular in the region between the doped or overdoped phase and the undoped phase in the active material. By means of the method according to the invention it is consequently possible to control, during the manufacturing of CBRAM memory cells, the diffusion of the ions in the chalcogenide material of the CBRAM memory cell, and to thus optimize the concentration profile between the doped and the undoped phases of the chalcogenide matrix. The present invention substantially utilizes the effect that movable ions such as alkali ions can, in insulating glasses, depending on the polarity, be drawn to the layer surface or be driven deeper into the volume or to the opposite surface, respectively, with a charge applied from outside. By means of this electrical charging, the concentration profile in the chalcogenide layer may be modified, which enables an optimization of the resulting diffusion profile. The chalcogenide layer may, for instance, be preconditioned already by means of photo diffusion. An optimization of the diffusion profile may, in this case, mean an expansion of the limiting area, a homogenization, or even an improvement with respect to the steepness of the profile between the undoped and the doped region in the chalcogenide layer. According to a further preferred embodiment of the present invention, the mobile material is diffused into or diffused back, respectively, by means of an electric charge of appropriate polarity which is applied on the active material preferably via the electrodes from outside. The charging of the electric charge may, for instance, be performed by inert gas ion beams or by contact with a high-frequency inert gas plasma. The potential of a floating surface, e.g. an Ag/Ge—Se layer, in the plasma is, on average, approximately 10V to 15V vis-à-vis the plasma potential of some eV with the plasma electron temperatures that are presently common in coating processes and etching processes. The potential is substantially determined by the electron temperature, and this temperature is, in turn, with a fixed plasma excitation frequency, dependent on the gas pressure and on the external high frequency power fed into the plasma. With these two parameters, the potential of the floating surface, the so-called floating potential, and thus also the depth profile of the metal ions, such as Ag, in the chalcogenide layer, such as Ge—Se, may be varied. Although basically also capacitively coupled high frequency plasmas can, for instance, be used with an excitation frequency of 13.56 MHz, an inductively excited plasma at a frequency of 27 MHz (high dense plasma) is particularly suited, such as it is at present used frequently for etching processes. In this inductively coupled plasma, the substrate with the Ag/Ge—Se-layer can be better arranged geometrically, and electric interactions with the electrode faces, such as they are employed in the capacitively coupled plasmas, can be avoided better. As a working gas for the plasma discharge, apart from argon (Ar), it is in particular also inert gases with lower masses such as neon (Ne) and helium (He) that are suited since, with these working gases, sputtering effects by hitting ions are negligible. A CBRAM memory cell manufactured pursuant to the method according to the invention comprises, due to the improved conditioning, more reliable and more distinctly evaluable electric switching properties. Moreover, no more forming step is necessary with the method according to the present invention. BRIEF DESCRIPTION OF THE DRAWINGS In the following, the invention will be explained in more detail with reference to several embodiments and the enclosed drawings. In the drawings: FIG. 1 shows a resistively switching memory cell and a central control means connected thereto. FIG. 2 shows the metal concentration in the chalcogenide layer during the manufacturing of a CBRAM memory cell after a doping process according to a preferred embodiment of the present invention. FIG. 3 shows the metal concentration or the concentration profile, respectively, of the mobile material in the chalcogenide layer during the manufacturing of a CBRAM memory cell during and after an overdoping process according to a preferred embodiment of the present invention. FIG. 4 shows the metal concentration or the concentration profile, respectively, of the mobile material in the chalcogenide layer during the manufacturing of a CBRAM memory cell during and after a retraction process according to a preferred embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION FIG. 1 shows schematically and by way of example the structure of a resistively switching memory cell 1 and a central control device 5 connected thereto. On an appropriate memory device or memory chip, respectively, a plurality of further memory cells that are of a structure similar or identical to the memory cell 1 illustrated in FIG. 1 may be arranged, e.g. in an appropriate memory cell field positioned side by side in a plurality of rows or columns. In the following, the basic functioning of a resistively switching memory cell is illustrated by way of example. The memory cells 1 may be any kind of resistively switching memory cells, e.g. Phase Change Memory Cells or CBRAM memory cells (CB=Conductive Bridging). Controlled by a central control device 5 provided on the memory device, specific writing or deleting processes may be performed in the memory cells 1 of the memory device. As results from FIG. 1 , each of the above-mentioned memory cells 1 comprises two appropriate metal electrodes 2 a , 2 b , i.e. an anode and a cathode. As a material for the electrodes 2 a , 2 b , a metal such as tungsten, or a metal alloy such as TiN, TiSiN, TiAlN, TaSiN, TiW, etc., or some other suitable electrode material may be used. A layer 3 of electrochemically active material is positioned between the electrodes 2 a , 2 b . The electrochemically active material consists of a chalcogenide compound, in particular a GeSe, GeS, AgSe, CuS compound, forming a chalcogenide matrix. In the chalcogenide matrix, mobile material such as alkali ions or metal ions, in particular of Ag or Cu, may move or be diffused into, respectively. The active material layer 3 that is at least partially doped with mobile material may be placed in a more or less conductive state by appropriate switching processes that are, for instance, controlled by the central control device 5 , in particular by applying appropriate current or voltage pulses of particular intensity and duration, wherein e.g. the more conductive state corresponds to a stored, logic “One” and the less conductive state to a stored, logic “Zero”, or vice versa. The chalcogenide compound material may also be placed in a relatively weakly conductive or a relatively strongly conductive state by appropriate switching processes that are, for instance, controlled by the central control device 5 , in particular by current or voltage pulses of particular intensity and duration, wherein e.g. the relatively strongly conductive state corresponds to a stored, logic “One” and the relatively weakly conductive state to a stored, logic “Zero”, or vice versa. In order to achieve, with the memory cell 1 , a change from a relatively weakly conductive state of the active material to a relatively strongly conductive state, an appropriate current pulse of appropriate intensity and duration may be applied at the electrodes 2 a , 2 b , e.g. controlled by the central control device 5 , the current pulse effecting, due to the relatively high resistance of the active material layer 3 , that electroconductive bridges are formed between the electrodes, the bridges having a lower ohmic resistance. FIG. 2 shows a diagram for illustrating the metal concentration in the chalcogenide layer during the manufacturing of a CBRAM memory cell after a doping process according to a preferred embodiment of the present invention. The X-axis of the diagram indicates the distance between the electrodes 2 a and 2 b between which the electrochemically active material or the chalcogenide matrix, respectively, of the CBRAM memory cell is positioned. The Y-axis of the diagram indicates the concentration of the mobile material or of the metal ions, respectively, in the chalcogenide matrix. FIG. 2 illustrates the schematic doping profile or the concentration profile K 1 , respectively, of the mobile metal after the conditioning process that has, for instance, been performed by means of photo diffusion. FIG. 2 reveals that, after the doping process according to the invention, in a preferred embodiment a doped or highly doped region H has been formed in the chalcogenide material, which, starting out from the first electrode 2 a , extends into the chalcogenide matrix. Since the penetration depth of the metal ions does not reach to the second electrode 2 b , an undoped region U remains between the doped or highly doped region H and the second electrode 2 , the undoped region extending few nanometers to the second electrode 2 b. Thus, after the doping process according to the invention, in a preferred embodiment a doping profile K 1 of the metal ions in the chalcogenide matrix has been produced, which extends via a doped or highly doped region H with an intensity of approx. 30% over a majority of the chalcogenide matrix, while an undoped region U remains between the doped or highly doped region H and the second electrode 2 b . This way, the limiting area between highly doped chalcogenide and undoped chalcogenide lies distinctly before the limiting area between the chalcogenide material and the second electrode 2 b. FIG. 3 shows a diagram for illustrating the metal concentration or the concentration profile, respectively, of the mobile material in the chalcogenide layer during the manufacturing of a CBRAM memory cell during and after an overdoping process according to a preferred embodiment of the present invention. Like in FIG. 2 , the X-axis of the diagram indicates the distance between the electrodes 2 a and 2 b between which the electrochemically active material or the chalcogenide matrix, respectively, of the CBRAM memory cell is positioned, while the Y-axis of the diagram indicates the concentration of the mobile material or the metal ions, respectively, in the chalcogenide matrix. FIG. 3 illustrates both the schematic doping profile or concentration profile K 1 , respectively, of the mobile metal after the conditioning process—in dashed line—and the schematic doping profile or concentration profile K 2 , respectively, of the mobile metal after the overdoping process—in continuous line. The overdoping process may, for instance, be performed by means of prolonged photo diffusion. FIG. 3 reveals that, by the overdoping process according to the invention, in a preferred embodiment the doped or highly doped region H in the chalcogenide material is extended further into the previously undoped region V until the doped or highly doped region H extends nearly through the entire chalcogenide matrix almost up to the second electrode 2 b. Thus, after the overdoping process according to the invention, in a preferred embodiment a doping profile K 2 of the metal ions in the chalcogenide matrix has been produced, which extends via a doped or highly doped region H with an intensity of approx. 30% nearly over the entire chalcogenide matrix from the first electrode 2 a almost up to the second electrode 2 b . This way, the limiting area between highly doped chalcogenide and undoped chalcogenide lies close to the limiting area between the chalcogenide material and the second electrode 2 b. After this overdoping process, the chalcogenide material is over-saturated too strongly for the operation of a CBRAM memory cell since the limiting area between highly doped chalcogenide and undoped chalcogenide has migrated too far into the chalcogenide material. Thus, no optimal operation or no operation at all of the CBRAM memory cell as a reversibly switching element is possible in this state of doping. FIG. 4 shows a diagram for illustrating the metal concentration or the concentration profile, respectively, of the mobile material in the chalcogenide layer during the manufacturing of a CBRAM memory cell during and after a retraction process according to a preferred embodiment of the present invention. Like in FIGS. 2 and 3 , the X-axis of the diagram indicates the distance between the electrodes 2 a and 2 b between which the electrochemically active material or the chalcogenide matrix, respectively, of the CBRAM memory cell is positioned, while the Y-axis of the diagram indicates the concentration of the mobile material or the metal ions, respectively, in the chalcogenide matrix. FIG. 4 illustrates both the schematic doping profile or concentration profile K 2 , respectively, of the mobile metal after the overdoping process—in dashed line—and the schematic doping profile or concentration profile K 3 , respectively, of the mobile metal after the retraction process according to the invention—in continuous line. The retraction process may, for instance, be performed by applying charges of appropriate polarity to the electrodes 2 a and 2 b. A comparison of the schematic doping profile K 2 of the mobile metal after the overdoping process—illustrated in dashed line—with the schematic doping profile K 3 of the mobile metal after the retraction process—illustrated in continuous line—reveals that the doped or highly doped region H is partially retracted from the chalcogenide material by means of the retraction process. By the retraction of the doping edge from the second electrode, a doped or highly doped region H remains in the chalcogenide layer after the retraction process, which extends from the first electrode 2 a over a part of the chalcogenide matrix. Now, an overdoped region Ü follows the doped or highly doped region H which, after the retraction, no longer extends up to the second electrode 2 b since the concentration course has been optimized retrogradely by the retraction process. This way, the chalcogenide material is conditioned correctly and better for the operation of a CBRAM memory cell than after the photo diffusion process. In this state of doping, an optimal operation of the CBRAM memory cell as a reversibly switching element is possible.
The present invention relates to a reproducible conditioning during the manufacturing of a resistively switching CBRAM memory cell comprising a first electrode and a second electrode with an active material positioned therebetween. The active material is adapted to be placed in a more or less electroconductive state by means of electrochemical switching processes. A CBRAM memory cell manufactured pursuant to the method according to the invention has, due to the improved conditioning, more reliable and more distinctly evaluable electrical switching properties. Moreover, no more forming step is necessary with the method according to the present invention.
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FIELD OF THE INVENTION Present invention relates to a method of bleaching pulp. More particularly the present invention relates to a method of ozone bleaching of chemical pulps pretreated to improve the selectivity of the bleaching agent to react with the lignin in the pulp. BACKGROUND OF THE PRESENT INVENTION It is conventional practice to bleach chemical pulps using bleaching agents such as chlorine and chlorine dioxide to produce pulps having the desired degree of whiteness. The use of chlorine has been described as detrimental to the environment particularly when contained in the effluent from the pulp mill, and thus efforts have been made to either eliminate chlorine and/or chlorine compounds or to reduce their use to an absolute minimum. Peroxides such as hydrogen peroxide have been used in different stages of bleaching to obtain the desired brightness of pulp and reduce the amount of chlorine applied. Ozone is also used as a bleaching agent to obtain the required brightness of chemical pulps. However, ozone has been known to degrade chemical pulps and thereby reduce their quality, in particular the strength characteristics of the chemical pulp. It is generally accepted in the industry that the viscosity of the pulp provides a very good indication of the strength potential of the pulp, i.e. the higher the viscosity the better the strength characteristics at a given kappa or permanganate no. It has also been suggested to replace the water, which is the medium in which the pulp is normally contained, with a suitable organic solvent such as ethanol and methanol, and to bleach the pulp using ozone gas as described for example in Japanese patent 7849107 published May 4, 1978 by Ueshima. This patent describes a process for recovering methanol from the digestion of wood chips with sodium hydroxide and Na 2 S and using this recovered methanol as a protector for the wood pulp during the ozone bleaching. In this patent air dried pulp was impregnated with methanol substantially free of water and was not acidified. Japanese patent 7890403 published Aug. 9, 1978 to Ueshima et al. describes another application of methanol followed by ozone bleaching of the methanol containing pulp. Again, in this patent, the water free pulp was impregnated with methanol which was free of water and was not acidified. The impregnated pulp was subsequently ozonated. This patent did not show as good results as those obtained in the earlier patent described above. An article entitled "The effect of cellulose protectors on ozone bleaching of kraft pulp" by Kamisima published in the Journal of Japanese Technical Association of the Pulp and Paper Industry, Vol. 31, 9, pp 62-70, September 1977, describes a number of different solvents that may be used to protect the pulp during an ozone bleaching stage. In these teachings, air dried pulp is treated with the organic solvents (alcohols), substantially free of water, and without addition of any acid, and then bleached with ozone. This publication indicates that ethanol is not effective in improving the viscosity of the ozone bleached pulp whereas the use of methanol does produce a positive result. An article entitled "The use of ozone in bleaching of pulps" by Liebergott et al. 1991 Pulping Conference, TAPPI Proceedings, pp 1-23, provides a review of the literature on ozone bleaching and describes a number of different chemicals that have been tried, i.e. added to the pulp before and in combination with an ozone bleaching stage in attempts to overcome or significantly reduce the detrimental effects of the ozone stage on the quality of the bleached pulp. This article does not list dioxane as having been tried. In Empire State Paper Research Institute report no. 54 titled "Ozone Bleaching of Kraft Pulps" by Rothenberg et al. October 1971 the use of various percentages of dioxane in water, combined with 1% acetic acid as a medium for ozone bleaching are reported. However the results obtained were not encouraging, and the ozone (lignin-carbohydrate) selectivity decreased when the concentration of dioxane increased above 35%. BRIEF DESCRIPTION OF THE PRESENT INVENTION It is an object of the present invention to provide an improved process for bleaching pulps using a gaseous bleaching agent such a ozone. Broadly, the present invention relates to an ozone bleached chemical pulp having a viscosity equivalent to a viscosity of about 21 mPa.s at a kappa no. of 5 for Northern softwood kraft pulp. Broadly the present invention relates to a method of bleaching a chemical pulp with a gaseous bleaching agent comprising uniformly impregnating said pulp with an aqueous medium that is a solvent for lignin, is fully miscible with water, but does not significantly swell cellulose in said pulp, said medium being present in an amount sufficient to significantly improve the availability of lignin to said bleaching agent, then uniformly subjecting said impregnated pulp to the action of said gaseous bleaching agent to preferentially attack and degrade said lignin to facilitate its subsequent removal. Preferably said bleaching agent will comprise ozone. Preferably said solvent will comprise dioxane. Preferably said dioxane will be present in an amount of at least 25% dioxane in water and preferably between 50 and 90% dioxane in water. BRIEF DESCRIPTION OF THE DRAWINGS Further features, objects and advantages will be evident from the following detailed description of the preferred embodiments of the present invention taken in conjunction with the accompanying drawings in which; FIG. 1 is a schematic illustration of the process of the present invention. FIGS. 2 and 4 each are a plot of kappa no. versus ozone consumed indicating the result of the presence of dioxane in the medium (impregnation solution) on the (lignin) ozone reaction efficiency. FIGS. 3 and 5 each are a plot of viscosity versus kappa no. showing the influence of the presences of dioxane in the medium (impregnation solution) on the (lignin-carbohydrate) ozone selectivity. DETAILED DESCRIPTION OF THE INVENTION A chemical pulp is introduced as indicated at 10 and impregnated in the impregnation zone 12 with a medium that is a solvent for lignin but does not significantly swell the cellulose of the pulp. This medium thus tends to expand the lignin to a much more significant extent than the cellulose which preferably will not expand and more preferably may shrink and thereby make the lignin more accessible for reaction with the gaseous bleaching agent. A solution of dioxane in water, more specifically a solution of 1,4-dioxane and water has been found to function as a satisfactory medium to obtain the desired results. The medium must contain at least 25% dioxane (% by weight) in water and preferably 50 to 90% dioxane by weight in water. The medium is introduced to the impregnation zone 12 as schematically indicated at 14. The pH of the pulp is also adjusted to that desired for use in the ozonation stage 24 (to be described below) normally to a pH of about 1.5 to 5, preferably 2 to 3 by the addition of a suitable mineral acid as indicated at 16. It is believed that the use of a mineral acid such as sulphuric acid as opposed to acetic acid contributes to the advantage obtained by the present invention. The consistency of the wet pulp mass is adjusted as indicated at 18 by any suitable means, for example by pressing, to that required during the ozonation stage 24 which preferably will be at a high consistency of between about 20 and 60% and more preferably to about 40%. The excess impregnation liquor is removed as indicated at 20. The pulp is then fluffed in the fluffer 22 at room temperature to obtain the desired particle open structure of the pulp mass which is required to obtain uniform contact of the ozone with the impregnated pulp in the ozonation stage 24. The fluffed pulp is then transferred to the ozonation stage 24 which may take place in any suitable a vessel, provided the pulp is uniformly contacted with the ozone containing gas stream. Uniform application of ozone to the pulp is very important to obtaining the required results. The total ozone charge, expressed as percentage on oven dried pulp, will be selected based on the desired lignin content or the final brightness required and the other or further processing steps (as indicated at 26) to be applied. The further processing steps as represented at 26 may include an extraction stage as indicated at 28. The ozonation stage 24 may consist of a plurality of individual applications of ozone with or without intermediate treatments to replace the impregnation liquor and subsequent refluffing of the pulp. The amount of ozone applied in the ozonation stage will generally be in the range of 0.5 to 3.0% based on the dry weight of the pulp. Generally the conditions used in the ozonation stage of the present invention normally will be essentially the same as the conditions applied in conventional ozonation bleaching of chemical pulp although if desired, lower temperatures may be used. After ozone treatment in the ozonation stage 24 the pulp may be further treated as indicated at 26 using any suitable treatment such as alkaline extraction, further bleaching stages using other suitable bleaching agents if desired, washed, etc. The following examples will help to clarify the present invention and illustrate its operation and effectiveness. EXPERIMENTAL PROCEDURE Examples The ozone bleaching experiments forming the examples were performed in a standard rotovap equipment modified with a fritted glass gas dispersion tube inserted in the rotating round bottom flask. About 10 grams of fluffed unbleached chemical pulp at approximately 40% consistency was contacted in the flask with a 3.83% (by weight) ozone in air mixture introduced through the gas dispersion tube at a flow rate of 1.04 l/min. The unreacted ozone leaving the flask is captured in a wash bottle filled with a KI solution and measured by iodometric titration. The ozone charge can be varied by changing the time that the ozone-air mixture flows through the pulp. The rotational speed of the flask was kept at a low level of 4-5 rpm. The ozonation of pulp was performed at room temperature. Example 1 Kraft Hemlock pulp (kappa no. 31.9, viscosity 35.8 mPa.s according to TAPPI standard 230 om-82) was treated with ozone in the rotovap equipment described above. In one case the pulp was impregnated with acidified (H 2 SO 4 ) water, in the other case an acidified (H 2 SO 4 ) mixture of 1,4 dioxane and water (70.5 weight % dioxane) was used. The pH of both solutions was 1.8. The pulps were contacted with different single charges of ozone. After the ozone treatment the pulps were thoroughly washed with tap water. The kappa no. and viscosity of the washed pulps were determined and the results are listed in Table 1. The results for the water- and dioxane-water impregnated pulps are also displayed in FIGS. 2 and 3 as respectively the kappa number versus ozone consumption and the viscosity versus kappa number. FIG. 2 shows that the delignification of the dioxane-water impregnated pulps is somewhat higher at the same ozone consumption than the water impregnated pulps. More important, however, is the substantially lower viscosity loss at the same kappa shown in FIG. 3 for the dioxane-water impregnated pulps after ozonation as compared to the water impregnated pulps. In other words, this example shows that the presence of dioxane in the pulp during ozone bleaching leads to improvements in the (lignin) ozone reaction efficiency and (lignin-carbohydrate) ozone selectivity. TABLE 1__________________________________________________________________________Dioxane-Water as Impregnation Liquid Water as Impregnation LiquidO.sub.3 (% on o.d. pulp) Kappa Viscosity O.sub.3 (% on o.d. pulp) Kappa ViscositySupplConsum No. (mPa.s) Suppl Consum No. (mPa.s)__________________________________________________________________________1.08 0.93 19.2 32.1 1.08 0.87 22.3 25.91.40 1.18 16.5 31.5 2.16 1.64 17.8 18.32.16 1.85 13.0 27.9 4.36 2.60 11.0 11.2__________________________________________________________________________ Example 2 The variable in this example was the composition of the dioxane-water solution used for impregnation of the kraft Hemlock pulp (kappa no. of 31.9, viscosity 35.8 mPa.s) before ozonation. Seven solutions with a weight percentage of dioxane of respectively 0, 4.8%, 9.8%, 25.4%, 48.2%, 70.6% and 100% were used. The dioxane-water solutions were not acidified and the measured pH varies from 3.7 to 4.0. The pH of the pure water impregnation liquid is around 7.0. After impregnation, the pulp was squeezed to remove excess of the impregnation liquid, fluffed, transferred at a consistency of about 32% to the flask of the rotovap equipment, and treated with a single charge of ozone. For the other experimental conditions see the Experimental Procedure. After ozonation the pulp was washed with large amounts of tap water, made into a handsheet and airdried. The kappa number and viscosity of the air-dried sheets of the different experiments are summarized in Table 2 which shows that as the weight percentage of dioxane in the dioxane-water impregnation solution increases, the viscosity of the ozonated pulp increases until a plateau is reached at 70.6% dioxane in water. The delignification appears to be most efficient at a dioxane weight percentage of 48.2%. Since 100% dioxane is not favourable in terms of delignification it can be concluded that the presence of water is essential to maximize the delignification. Comparison of the results obtained with 0% and 70.6% dioxane in water shows that in the former case the viscosity drops from 35.8 mPa.s to 22.4 mPa.s, while in the latter a viscosity of 32.2 mPa.s is obtained at a slightly larger ozone consumption (resp. 1.6 versus 1.73%). TABLE 2______________________________________ O.sub.3 O.sub.3 Supplied ConsumedDioxane in Water (% on o.d. (% on o.d. Kappa Viscosity(weight %) pulp) pulp) No. (mPa.s)______________________________________0 1.96 1.60 21.8 22.44.8 2.16 1.59 22.0 24.49.8 2.16 1.70 20.0 24.125.4 2.16 1.68 19.1 27.348.2 2.16 1.71 18.4 29.970.6 2.16 1.73 19.4 32.2100 2.96 2.41 21.5 32.2______________________________________ Example 3 Comparison of the results in Example 1 and 2 obtained with 70.6% dioxane in the dioxane-water impregnation liquid indicates that the (lignin) ozone efficiency is much improved at the lower pH, while the pH has only a minor effect on the (lignin-cellulose) ozone selectivity. This Example investigates the combined effect of the pH and dioxane concentration of the impregnation solution on the ozone bleaching response of the kraft Hemlock pulp (kappa 31.9, viscosity 35.8 mPa). In two series of tests the pH of the impregnation solution was adjusted to respectively 1.8 and 2.3 by addition of 4N sulfuric acid. In these two series of tests a single ozone charge of 1.08% was applied and the pulp consistency was about 40%. The results thus obtained are listed in Table 3. It is again apparent from Table 3 that the viscosity of the ozonated pulp increases with increasing dioxane weight percentage of the impregnation solution. Comparison of the results obtained at the two pH levels shows that the higher viscosities are obtained at a pH of 2.3, while the kappa number of corresponding pulps at the two pH levels are approximately the same. Comparison of the results in Tables 2 and 3 shows that the amount of ozone charged in the case without acidification is about double that in the two cases with sulfuric acid addition, while the delignification achieved is similar in all three cases. Therefore, these experiments show that the addition of a small amount of a mineral acid is very beneficial to achieve a high (lignin) ozone reaction efficiency while a large improvement in the (lignin-cellulose) ozone selectivity is obtained when a dioxane weight percentage of about 70-75% is used for the dioxane-water impregnation solution. TABLE 3__________________________________________________________________________pH 1.8 pH 2.3 O.sub.3 O.sub.3 %DioxaneKappa Viscosity (% on pulp) Dioxane Kappa Viscosity (% on pulp)(wgt %)No. (mPa.s) Suppl Consum (wgt %) No. (mPa.s) Suppl Consum__________________________________________________________________________0 22.3 25.9 1.08 0.87 0 20.6 23.9 1.08 0.8610 20.2 24.7 1.08 0.88 10 20.8 26.7 1.08 0.8725 20.3 27.1 1.08 0.86 25 20.2 28.0 1.08 0.8650 20.4 29.8 1.08 0.88 50 19.4 31.7 1.08 0.8670.6 19.3 31.8 1.08 0.93 75 20.5 33.4 1.08 0.90__________________________________________________________________________ Example 4 The pulp was ozonated after impregnation with an acidified (pH of 1.8) dioxane-water solution containing 70.6 weight percent dioxane. Excess solution was subsequently removed by squeezing the impregnated pulp and after fluffing the pulp was treated in the rotovap equipment at a consistency of about 40%. In all experiments the same unbleached Hemlock kraft pulp as in the previous example was used. In the first experiment the unbleached pulp was treated with 2.16% O 3 on o.d. pulp (actual ozone consumption was 1.85%). The O 3 treated pulp was washed with water and air dried. Its kappa number and viscosity are respectively 13.0 and 27.9 mPa.s. The ozone treated and washed pulp was subsequently reimpregnated with dioxane-water, fluffed and subjected to another ozone charge of 2.59% on pulp (actual consumption was 1.67%). The pulp consistency during ozonation was again about 40%. After a water wash and air drying it was found that the pulp had a kappa number of 5.0 and a viscosity of 16.2 mPa.s. In another series of tests, the unbleached Hemlock kraft pulp was treated with 1.08% O 3 on o.d. pulp (actual consumption 0.93%). The kappa no. and viscosity of the water washed pulp after this first ozonation stage were 19.2 and 32.1 mPa.s respectively. After reimpregnation, consistency adjustment and fluffing, the pulp was treated with another ozone charge of 1.08% on o.d. pulp (1.0% O 3 was actually consumed). The kappa no. and viscosity of the water washed pulp after the two ozone stages are 9.6 and 25.8 mPa.s respectively. This is somewhat better in terms of (lignin-cellulose) ozone selectivity than the pulp obtained in the first series of tests where 2.16% of O 3 was charged in one stage, and resulted in a kappa no. and viscosity of respectively 13.9 and 27.9 mPa.s. Finally, a third ozone bleaching stage with a 0.54% O 3 charge (actual consumption 0.50%) was applied to the pulp which had been ozonated twice with a charge of 1.08% O 3 in each stage. The kappa no. and viscosity of the water washed pulp thus obtained were 4.6 and 20.9 mPa.s respectively. This compares to a kappa no. and viscosity of respectively 5.0 and 16.2 mPa.s for the pulp obtained in the first test series after two stages of ozone bleaching at a charge of respectively 2.16% and 2.59% O 3 each. This shows that stagewise ozone bleaching with relatively small ozone charges of about 1% is better in terms of both ozone efficiency and selectivity than applying larger charges of ozone (>2.0%) in fewer stages. The experiments also show that an unbleached kraft pulp with a kappa of 31.9 can be delignified to a kappa number of 4.6 and a viscosity above 20 mPa.s when ozone is charged in three stages of 1.08%, 1.08% and 0.54%. The total ozone consumption for all three stages is 2.53% on o.d. pulp. It is believed that all the ozone can be added in one stage if good contact between the pulp and the ozone containing gas can be maintained. The superior ozone bleaching response of pulp impregnated with a dioxane-water solution rather than with water alone is clearly shown in FIGS. 4 and 5 which are respectively the (lignin) ozone reaction efficiency and the (lignin-cellulose) ozone selectivity when bleaching is performed in three consecutive stages with ozone charges of 1.08%, 1.08% and 0.54% respectively. In both series of experiments the pH of the impregnation liquid is 1.8, and the pulp consistency is approximately 40%. The weight percentage of dioxane in the dioxane-water impregnation liquid is 70.6%. The results in FIGS. 4 and 5 respectively show that the presence of dioxane does not significantly change the ozone reaction efficiency but leads to a dramatic reduction in the degradation of cellulose. Although the disclosure has shown examples of softwood kraft pulp, the invention is also believed to be applicable to hardwood kraft pulps, oxygen bleached pulps and other pulps produced by a chemical or organic solvent based pulping process, and is expected to produce equivalent improved results compared to those obtained with a conventional ozone treatment. Obviously the absolute values of the viscosity and kappa no. will reflect the type of pulp being processed. Thus the term equivalent to a Northern softwood pulp is to be interpreted as requiring suitable scaling of the absolute values normally valid for the above mentioned pulp types. Having described the invention modifications will be evident to those skilled in the art without departing from the scope of the invention as defined in the appended claims.
A method of bleaching a chemical pulp with a gaseous bleaching agent by uniformly impregnating the pulp with a solvent for lignin and that is fully miscible with water but does not significantly swell cellulose so that the availability, of lignin to the bleaching agent is significantly improved, then subjecting the impregnated pulp to the action of the bleaching agent to preferentially attack the lignin for its subsequent solubilization and separation from the pulp.
3
COPYRIGHT NOTICE AND AUTHORIZATION [0001] This patent document contains material which is subject to copyright protection. [0002] © Copyright 2012. Chevron Energy Solutions Company, a division of Chevron U.S.A. Inc. All rights reserved. [0003] With respect to this material which is subject to copyright protection. The owner, Chevron Energy Solutions has no objection to the facsimile reproduction by any one of the patent disclosure, as it appears in the Patent and Trademark Office patent files or records of any country, but otherwise reserves all rights whatsoever. FIELD OF THE INVENTION [0004] This invention relates to system and method for a foldable solar canopy. BACKGROUND OF THE INVENTION [0005] Solar energy is a clean, renewal energy source. Photo-electro voltaic cell technology is increasing rapidly and makes installation of solar collector panels housing the photo-electro voltaic cells more and more economically feasible. Beyond the photo-electro voltaic cell technology itself are the problems of placement and support of the solar collector panels. Large numbers of solar collector panels must be assembled in series to achieve useful power production. In remote areas these may be placed on the ground without interfering with land use. In more developed areas, it is desirable to place the solar collector panels such that the land may also be used for other purposes, e.g., for parking lots, school/office hallways, playgrounds, or sports fields. To achieve this requires an elevated structure to support the solar collector panels. [0006] Prior known systems for elevated structures for supporting the solar collector panels are inefficient and overly expensive since they require excessive amounts of materials, particularly steel support elements, and on-site construction. Also, known systems take an excessive amount of time to install. [0007] It is desirable to have a method and system which overcomes the deficiencies of known systems. The instant invention provides such a solution. SUMMARY OF THE INVENTION [0008] The invention includes a solar canopy a structure capable of folding into a compact form for transporting, and for simple unfolding for attachment to a base. The structure comprises a plurality of hingably interconnected solar panel arrays each having a plurality of solar panels, a solar panel support channel, and a support beam; wherein the plurality of solar panels is attached to top portions of the solar panel support channel, and a bottom portion of the solar panel support channel is attached to a top portion of the support beam, the support beam having a hinged joint for cooperating in folding into mutual, near coplanar juxtaposition; and whereby the structure, when unfolded comprises a solar canopy and is T-shaped viewed on end. [0009] In another embodiment, the invention includes a solar canopy a solar canopy structure capable of folding into a compact form for transporting, and for simple unfolding for attachment to a foundation, the structure comprising one or more support beams for supporting a plurality of solar panel support channels and a plurality of solar panels, the support beams having an integral hinge for cooperating in folding into a compact form for transporting. [0010] These and other features and advantages of the present invention will be made more apparent through a consideration of the following detailed description of a preferred embodiment of the invention. In the course of this description, frequent reference will be made to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS [0011] FIG. 1 is one embodiment of a flow chart for the process of manufacturing, transporting, and installing the foldable solar canopy structure of the invention. [0012] FIG. 2 is one embodiment of a flow chart for the process of preparing the site prior to installing the foldable solar canopy structure of the invention. [0013] FIG. 3A is a side view of one embodiment of the foldable solar canopy structure of the invention when folded. [0014] FIG. 3B is a perspective view of one embodiment of the foldable solar canopy structure of the invention when folded. [0015] FIG. 4 is a side view of one embodiment of the foldable solar canopy structure of the invention unfolded and installed. [0016] FIG. 5A is a perspective view of one embodiment of multiple foldable solar canopy structures of the invention unfolded. [0017] FIG. 5B is a side elevation view of one embodiment of the foldable solar canopy structure of the invention unfolded and installed. [0018] FIG. 6 is a front elevation view of one embodiment of the foldable solar canopy structure of the invention unfolded. [0019] FIG. 7 is an isometric view of one embodiment of the foldable solar canopy structure of the invention unfolded. [0020] FIG. 8 is a side elevation view of an L-shaped embodiment of the foldable solar canopy structure of the invention unfolded. [0021] FIG. 9 is a side elevation view of an L-shaped embodiment of the foldable solar canopy structure of the invention folded. [0022] FIG. 10 is an isometric view of an L-shaped embodiment of the foldable solar canopy structure of the invention folded. [0023] FIG. 11A is an inside elevation view of another embodiment of a portion of the folded foldable solar canopy structure and bracing of the invention. [0024] FIG. 11B is an outside elevation view of another embodiment of a portion of the folded foldable solar canopy structure and bracing of the invention folded. [0025] FIG. 12 is a side elevation view of another embodiment of a portion of the folded foldable solar canopy structure and bracing of the invention. [0026] FIG. 13 is an isometric view of another embodiment of a portion of the folded foldable solar canopy structure and bracing of the invention folded. [0027] FIG. 14 is an isometric/exploded view of another embodiment of the bracing of the invention. [0028] FIG. 15 is an isometric/exploded view of another embodiment of the bracing of the invention. [0029] FIG. 16 is an isometric/exploded view of another embodiment of the bracing of the invention. [0030] FIG. 17 is a top/exploded view of another embodiment of the bracing of the invention. [0031] FIG. 18 is a top/exploded view of another embodiment of a bracing element of the invention. DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS [0032] Field labor prices are expensive. By designing a folding structure so it can be shipped, a majority of the field labor is moved into the factory. This allows for lower labor costs going into the installation of Photovoltaic Solar Shade Structures. A known method of partially addressing this problem is by manufacturing portions of the structures in the factory, then shipping those portions out in parts, and assembling them in the field. The Manufactured Folding Photovoltaic Shade Structure of the invention allows for more components to be connected, wired, tested and even commissioned in the factory before being sent to the site for installation. [0033] The invention includes a one or two or multiple column photovoltaic shade structure which is fully assembled in a factory. This assembly in some embodiments includes electrical panels, inverters, combiner boxes, lights, conduit, AC panel board or DC combiner, pull boxes, wire management components, strut, conduit, monitoring equipment and any other components which will be on the structure in the field. The assembled units are fully tested and partially commissioned in the factory before being shipped to the site for installation. In one embodiment, the largest manufactured shade structures would be up to approximately 40-50 feet plus long and weigh less than approximately 20,000 lbs. [0034] Once there is a fully assembled Shade Structure of the invention in the factory it needs to be transported to the site. This design of the invention will allow the units to be fold up while remaining wired, placed on a truck and shipped to the site. In one embodiment, specially designed shipping bracing are used to allow the Shade Structure to be folded up for shipping without damaging the equipment. [0035] In one embodiment, a horizontal beam for supporting channels and solar panels is “broken” (or articulated) in 3 locations; one in the center at the column and beam connection point. The other two broken locations are outward from the center/column and before the two outer ends of the beam. In one embodiment the outer broken locations are between the outer most solar panel and the adjacent solar panel. Hinges or other pivotable structures are part of or attached to the broken portions of the beam. In one embodiment the hinges are built into the plate steel and use bolts or steel rods as the hinge point. When the Manufactured Folding Photovoltaic Shade Structure of the invention is installed on site, each side of the structure is raised, one at a time, the bolt holes will be lined up and the bolts can be installed. If bolts are used for the hinge point, the bolts are also tightened down. [0036] In one embodiment, as the units are being unfolded the shipping, installation and transportation bracing is removed in the same order it was installed. The bracing can also be adjusted on site to ensure footing and Manufactured Folding Photovoltaic Shade Structure column alignment. [0037] Benefits of the invention include predictable/repeatable results, reduced financial risk, accuracy in scheduling, and accuracy in pricing. The benefits also include cost savings, leveraged scale to reduce cost, lower labor rates, manufacturing improvements in efficiency, enhanced procurement processes, refined and predictable pricing, controlled fabrication environment, and facilitates various design and construction tools. [0038] These and other features and advantages of the present invention will be made more apparent through a consideration of the following detailed description of a preferred embodiment of the invention. In the course of this description, frequent reference will be made to the attached drawings. [0039] FIG. 1 is one embodiment 100 of a flow chart for the process of manufacturing, transporting, and installing the foldable solar canopy structure of the invention. First in assembly step 110 the foldable solar canopy structure (also referenced as the Folding Photovoltaic Shade Structure) is manufactured by pre-assembling the separate components. Then in folding step 120 , cross-braces 322 (see, e.g., FIG. 3A ) are attached. The structure is folded and collapsed to prepare for transport to the installation site. In the loading step 130 the foldable solar canopy structure is loaded onto a transport vehicle (e.g., flat bed truck, barge, flat bed train car) for transport to the installation site. If the installation site is not prepared 140 , then the site is prepared 150 . If it is prepared the foldable solar canopy structure is mounted 160 on the prepared site, i.e., mount columns on prepared bases. In unfolding step 170 , the structure is unfolded and locked in position and any shipping brackets are removed. Then in wiring step 180 , the electrical wiring is connected between the foldable solar canopy structure and any site electrical connection for distribution or storage of solar-produced electrical energy. This concludes 190 the method of constructing, transporting, and installing the foldable solar canopy structure. [0040] FIG. 2 is one embodiment of a flow chart for the process of preparing the site prior to installing the foldable solar canopy structure 300 ( FIG. 3A ). The site for installation of the foldable solar canopy structure is prepared by a first grading and boring step 210 to level the ground as needed and bore holes for insertion of footing material, e.g., reinforced concrete, metal beam or column, or other now known or future developed footing materials. In another embodiment no footing holes are prepared and instead, e.g., a column or beam is forced into the ground. Any underground electrical infrastructure and other footing preparations are then done 220 . In the embodiment where the footing material is concrete, the concrete is then poured into the prepared footing holes, together with and reinforcement bars 230 . Care must be taken to place the footings for alignment with the foldable solar canopy structure. In one embodiment using concrete footings with embedded footing bolts protruding out of the top of the set concrete, brackets or templates should be used to insure proper placement of the footing bolts. [0041] FIG. 3A is a side view of one embodiment of the foldable solar canopy structure 300 when folded. Beam support columns 318 are for attaching at the base to a footing (not shown). The beam support columns 318 are removably attached to, e.g., reinforced concrete bollards by bolting the beam support columns 318 to the reinforced concrete bollards via bolts embedded in the concrete of the bollards and flanges 346 integral with the beam support columns 318 . [0042] Foldable Zee channel support beams have a first section 314 for hingably attachment at an inner end (relative to the center of the structure) to the top of the beam support columns 318 via hinge flange 313 . In one embodiment, the support beams are made of tube steel. An outer end of first section 314 hingably connects to a second section 317 of the Foldable Zee channel support beams via hinge flange 315 . The first section 314 in one embodiment has sufficient length for at least two solar panels 310 side-by-side. The second section 317 in one embodiment has sufficient length for at least one solar panel 310 . For each solar panel 310 on each of the first section 314 and second section 317 , there are at least two Zee channels 312 attached with an axis substantially perpendicular to the axis at least two Zee channel support beams sections 314 and 317 . While the support beams are referred to as “Zee channel” support beams, the types of channels or other support between the support beams and the solar panels may include any other known or future developed materials, e.g., C-channels or other suitable materials. [0043] Each Zee channel 312 is of sufficient length to so that it spans two Zee channel support beams, 314 (first section) and 317 (second section), where the channel support first and second sections, 314 and 317 , are parallel and in line and set at a sufficient distance apart to accommodate a plurality of solar panels 310 end-to-end or side-by-side supported by the Zee channels 312 , which are supported by the channel support beams, first and second sections, 314 and 317 , which are supported by the beam support columns 318 , one beam support column 318 per each set of two channel support beams, first and second sections, 314 and 317 . In one embodiment, each set of adjacent Zee channels 312 is disposed in a reverse orientation to each adjacent Zee channel 312 . [0044] FIG. 38 is a perspective view of one embodiment of the foldable solar canopy structure 300 when folded. [0045] FIG. 4 is a side view of one embodiment of the foldable solar canopy structure of the invention unfolded and installed. The channel support beams first and second sections, 314 and 317 , in one embodiment are a single beam with three or four hingable, foldable, pivotable, or collapsible sections. Alternately, the channel support beams first and second sections, 314 and 317 , are two beams, each having two sections, first/inner section and second/outer section 314 and 317 , respectively. In each case the sections are pivotably or hingably connected such that the beam(s) can either be folded or unfolded. The folded state is used during transportation from the manufacturing site to the installation site. The unfolded state is for the final operating configuration after installation. The hingable/pivotable connections within or between the channel support beams 314 and 317 are any known or future developed means providing for folding or unfolding and locking in the unfolded position with sufficient structural integrity for the intended load and any desired safety margin. The hingable/pivotable connections are in one embodiment integral to the beams and in another embodiment a separate hinge component fixably attached to the beam. [0046] In one embodiment the inner/first sections 314 will have integral or attached hinges on both ends, one for hingable connection to a top portion of the beam support column 318 and one for hingable connection to the inner end of the outer section 317 . In that embodiment the outer section 317 has a hingable connection only at its inner end for hingable connection to the outer end of inner/first section 314 . Other configurations are within the scope of the invention, e.g., 3-4 sections rather than 2 sections channel support beams first and second sections 314 and 317 . In the folded state the height and width of the foldable solar canopy structure 300 is sufficient for transportation on the intended mode of transportation, e.g., barge, truck, or train car. Braces 322 are added as needed and optionally only during transportation, e.g., to maintain the folded state or to provide increased strength of the solar panels 310 to the Zee channels 312 to account for the sheer force that would not be present in the final unfolded state. In this embodiment, when unfolded, the two channel support beams first and second sections 314 and 317 , one on each side of the beam support column 318 , form in effect a single beam aligned on the same axis and connected end-to-end. Ancillary electrical equipment (shown in other figures, e.g., FIG. 3A ), e.g., weather station 321 , inverter 316 , AC panel board 319 can be attached beneath the canopy, e.g., attached to a part of the beam support columns 318 or channel support beams first and second sections 314 or 317 . [0047] FIG. 5A is a perspective view of one embodiment of a plurality of the foldable solar canopy structure 300 aligned end-to-end and unfolded and installed and attached to bollard/footing 320 . Any number, e.g., 10, 20, 50, foldable solar canopy structures 300 may be aligned end-to-end to achieve the desired electric energy generation and to fit the available space at the site. Typically, the plurality of foldable solar canopy structures 300 are electrically connected in series. In this embodiment the bollard/footing 320 is above grade. In another embodiment the top of the bollard/footing is at grade. Ancillary electrical equipment, e.g., a D.C.-A.C. inverter is attached beneath the canopy, e.g., attached to a part of channel support beams first and second sections 314 or 317 . [0048] FIG. 5B is a side elevation view of one embodiment of the foldable solar canopy structure of the invention unfolded and installed. Beam support column 318 supports the rest of the structure. Hinge flanges 313 are attached to or integral with the top end of beam support column 318 . A foldable Zee channel support beam first and second sections ( 314 , 317 ) is attached to a hinge flange 313 . In one embodiment, the foldable Zee channel support beams are comprised of a first section 314 proximate to the beam support column 318 and a second section 317 . The first and second sections are connected via hinge 315 which is integral to or attached to the first and section sections ( 314 and 317 ). The end of the first section proximate to the beam support column 318 is connected to or integral with the hinges/hinge flanges 313 . The hinge flanges 313 and 315 permit the foldable Zee channel support beams to fold downwards towards the ground. In folded/collapsed position the foldable solar canopy structure 300 has a much smaller “footprint” or width making it a suitable size for transport via truck, barge, or train. [0049] Zee channels 312 are fixedly attached at perpendicular angles to the foldable Zee channel support beams at their upper side. A plurality of solar panels 310 are fixedly attached to the upper portions of the Zee channels 312 . In one embodiment the solar panels 310 are attached such that its lengthwise axis is perpendicular to the lengthwise axis of the Zee channels 312 . In one embodiment the solar panels 310 are spaced on the Zee channels 312 so as to about one another or be within a few inches or less on each side so as to maximize solar panel area for each structure. In one embodiment gaps are left between the solar panels over the channel support beams sufficient to permit attachment of braces (not shown) and for attachment of “toe” line or other line or cable for use in unfolding/expanding the foldable solar canopy structure 300 at the installation site. The hinge flanges 315 and 313 release and lock using any conventional devices such as pins or bolts (not shown) which slide into place to prevent articulation of the hinge. Other mechanisms are latches connecting the 2 parts of the hinge. Other mechanisms are clasps, overlapping lips, interacting groves, and other known or future developed mechanisms. [0050] FIG. 6 is a front elevation view of one embodiment of the foldable solar canopy structure of the invention unfolded and installed. It shows the plurality of Zee channels 312 supporting a plurality of solar panels 310 . [0051] FIG. 7 is an isometric view of one embodiment of the foldable solar canopy structure of the invention unfolded and installed. In addition to the other elements of the structure, it shows the cross-brace 322 which in one embodiment connects in multiple locations between adjacent Zee channels 312 for structural stability. Light 324 is also depicted. Other components or accessories may also be attached under the expanded foldable solar canopy structure 300 , e.g., electrical boxes 319 , inverters 316 , or other control or measurement equipment 321 . [0052] FIG. 8 is a side elevation view of an L-shaped embodiment of the foldable solar canopy structure 800 of the invention unfolded and installed. Beam support columns 318 are for attaching at the base to a footing (not shown). The beam support columns 318 are removably attached to, e.g., reinforced concrete bollards (not shown) by bolting the beam support columns 318 to the reinforced concrete bollards via bolts (not shown) embedded in the concrete of the bollards and flanges 346 integral with the beam support columns 318 . [0053] One of the foldable Zee channel support beams first and second sections ( 314 and 317 ) have a first section 314 for hingably attachment at an inner end (relative to the center of the structure) on one side at the top of the beam support columns 318 via hinge flange 313 . In one embodiment, the support beams are made of tube steel. An outer end of first section 314 hingably connects to a second section 317 of the Foldable Zee channel support beams via hinge flange 315 . The first section 314 in one embodiment has sufficient length for at least two solar panels 310 side-by-side. The second section 317 in one embodiment has sufficient length for at least one solar panel 310 . The opposing foldable Zee channel support beam ( 810 ) has only one section, having a first end attached to hinge flange 313 and an opposite end not attached. [0054] For each solar panel 310 on each of the first section 314 and second section 317 of one foldable Zee channel support beams first and second sections ( 314 and 317 ) and the other foldable Zee channel support beam ( 810 ), there are at least two Zee channels 312 attached with an axis substantially perpendicular to the axis at least two Zee channel support beams sections, 314 and 317 , and 810 . While the support beams are referred to as “Zee channel” support beams, the types of channels or other support between the support beams and the solar panels may include any other known or future developed materials, e.g., C-channels or other suitable materials. [0055] Each Zee channel 312 is of sufficient length to so that it spans two Zee channel support beams first and second sections 314 and 317 , and 810 , where the channel support beams first and second sections 314 and 317 , and 810 are parallel and in line and set at a sufficient distance apart to accommodate a plurality of solar panels 310 end-to-end or side-by-side supported by the Zee channels 312 , which are supported by the channel support beams first and second sections 314 and 317 , and 810 , which are supported by the beam support columns 318 , one beam support column 318 per each set of two channel support beams first section and second section 314 and 317 . In one embodiment, each set of adjacent Zee channels 312 is disposed in a reverse orientation to each adjacent Zee channel 312 . In an alternate embodiment there is only a Zee channel support beam on one side of beam support column 318 . [0056] FIG. 9 is a side elevation view of an L-shaped embodiment of the foldable solar canopy structure 800 of the invention folded. Since one of the channel support beams first and second sections 314 and 317 is longer than the other 810 , the former channel support beams extend farther down in the folded position. [0057] FIG. 10 is an isometric view of an L-shaped embodiment of the foldable solar canopy structure of the invention folded. [0058] FIG. 11A is an inside elevation view of another embodiment of a portion of the folded foldable solar canopy structure and bracing of the invention 1300 . In this figure the solar panels 310 are omitted for clarity. The description of FIG. 3A above is incorporated herein by reference in its entirety. Brace assembly 1301 is removably attached to beam support column 318 and to each of the channel support beams first and second sections 314 and 317 . The brace assembly 1301 is for stabilizing the solar canopy structure 1300 during transport. Brace assembly 1301 is comprised of a first and second brace clamp, here shown as single element 1310 , for removable attachment to each of the channel support beams first and second sections 314 and 317 , a third brace clamp 1315 for removable attachment to beam support column 318 , and a shock absorber 1317 for attaching the third brace clamp to each first and second brace clamp 1310 . In another embodiment shock absorber 1317 is replaced with a fixed length strut. FIG. 11B is an outside elevation view of another embodiment of a portion of the folded foldable solar canopy structure and bracing of the invention 1300 shown in FIG. 11A . [0059] Further detail of the brace assembly will be provided in other figures. The bracing assembly 1301 is suitable for use with a folded foldable solar canopy structure 1300 having either a single or multiple beam support columns 318 . In one embodiment there is one bracing assembly 1301 for each beam support column 318 . FIGS. 11A and 11B show opposing views of a single beam support column 318 . [0060] FIG. 12 is a side elevation view of another embodiment of a portion of the folded foldable solar canopy structure and bracing of the invention 1300 folded. This embodiment has two beam support columns 318 . In addition to the other bracing elements (not all shown) discussed in FIGS. 13-17 , this embodiment depicts an additional brace component, the support bar 1325 . Support bar 1325 attaches at ends to the third brace clamp 1315 attached to each beam support column 318 . In one embodiment support bar 1325 is a fixed length and in another embodiment it has a variable/adjustable length. In addition to overall stability, support bar 1325 joins the bottom portion of the two beam support columns 318 for maintaining a fixed spacing between the beam support columns, i.e., typically substantially equal at the top and bottom of the columns, so that the columns are substantially vertical. This facilitates installation at the site, i.e., where a foundation is prepared with bolts positioned for attachment of columns 318 . [0061] FIG. 13 is an isometric view of another embodiment of a portion of the folded foldable solar canopy structure and bracing of the invention in the folded position. First and second brace clamps (jointly referenced here as 1310 ) attach to each of the channel support beams first and second sections 314 and 317 and to each other. The third brace clamp 1315 attaches to beam support column 318 , and a strut/shock 1317 attaches to third brace clamp 1315 to each first and second brace clamp 1310 . Third brace clamp 1315 has connection flanges 1330 for attachment to support bar 1325 . [0062] FIG. 14 is an isometric/exploded view of another embodiment of the bracing of the invention. In this figure and in FIGS. 15-17 , the elements of the brace assembly 1301 ( FIG. 11A ) are described in more detail. First and second brace clamps 1310 in one embodiment is comprised of first brace clamp 1350 removable attached to second brace clamp 1370 . The attachment in one embodiment is via attachment flanges 1385 on second brace clamp 1370 and mating flanges (not shown) on first brace clamp 1350 . Bolt/pin 1375 passes through eyes in the attachment flanges to join them together. Other methods of removable attachment may be used. First brace clamp comprises two elements; i.e., first U-shaped body 1360 and shallow indented cover plate 1355 . Second brace clamp comprises two elements, i.e., second U-shaped body 1380 and flat cover plate 1365 . For each brace clamp the U-shaped body removably attaches to the respective cover plate, thus attaching to channel support beams first and second sections 314 and 317 . [0063] Third brace clamp 1315 comprises two elements, i.e., third U-shaped body 1340 and flat cover plate 1345 . U-shaped body 1340 removably attaches to the flat cover plate 1345 , thus attaching to support column 318 . Third brace clamp 1315 removably attaches to second brace clamp 1370 via shock absorber 1317 or other strut, rod, or other suitable means. Shock absorber 1317 removably attaches to third brace clamp 1315 via flange 1335 and a corresponding flange (not shown) on second brace clamp 1370 . [0064] FIGS. 15 , 16 , and 17 are isometric/exploded views of one embodiment a portion of the bracing assembly 1301 . For each of the first, second, and third brace clamps ( 1350 , 1370 , and 1315 , respectively), the respective U-shaped body attaches via bolts through holes (e.g., 1346 and 1347 ). Other attachment mechanisms may be used. [0065] FIG. 18 is a top/exploded view of another embodiment of a bracing element of a portion of the bracing assembly 1301 ( FIG. 11A ). Shock absorber 1317 is comprised of a first strut portion 1810 , second strut portion 1805 and connector flanges 1815 and 1817 . Other known connection methods may be used either rigid or designed to absorb shock. [0066] Other embodiments of the present invention and its individual components will become readily apparent to those skilled in the art from the foregoing detailed description. As will be realized, the invention is capable of other and different embodiments, and its several details are capable of modifications in various obvious respects, all without departing from the spirit and the scope of the present invention. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not as restrictive. It is therefore not intended that the invention be limited except as indicated by the appended claims.
A structure capable of folding into a compact form for transporting, and for simple unfolding for attachment to a base, the structure including: two or more hingably interconnected solar panel arrays each having a two or more of solar panels, a solar panel support channel, and a support beam; wherein the two or more solar panels are attached to top portions of the solar panel support channel, and a bottom portion of the solar panel support channel is attached to a top portion of the support beam, the support beam having a hinged joint for cooperating in folding into mutual, near coplanar juxtaposition; and where the structure, when unfolded includes a solar canopy and is T-shaped viewed on end.
8
BACKGROUND OF THE INVENTION This invention relates to a device that is permanently set under the driveway foundation to provide for an ice free surface. More particularly, the invention relates to a device that is preferably used in conjunction with a motor vehicle exhaust system. This invention substantially reduces the need to manually remove snow and ice from the driveway surface. The prior art teaches a variety of devices that are adapted to hasten the melting of snow. For example, U.S. Pat. Nos: 1,349,136; 2,515,341; 3,151,613; 3,189,021; 3,683,152; and others. These devices are different, however, in that they either can only melt the snow at a relatively limited area and still require manual manipulation, or do not function in conjunction with a motor vehicle exhaust system. SUMMARY OF THE INVENTION It is accordingly an object of the instant invention to avoid one or more drawbacks of the prior art. It is another object of the invention to provide for a permanent de-icing apparatus to preferably be used in conjunction with motor vehicle exhaust systems. These and other objects of the invention will become more apparent from the following detailed disclosure and claims and by reference to the accompanying drawings, in which: FIG. 1 is a front elevational view partially exploded, showing the device installed in the working position; and FIG. 2 is a top plan view in perspective of the driveway with the device in place. Broadly speaking, the instant invention includes the provision of a support surface de-icing apparatus especially adapted for use in conjunction with a motor vehicle comprising an elongated hollow conduit substantially imbedded under the surface and having first and second ends, exterior the surface and adapted to receive and permit the flow of a fluid therethrough, a first flexible conduit member open at both ends, one end communicating with the first end of the elongated conduit, the other end of the flexible conduit communicating with a source of heat exchangeable fluid, the second end of the elongated conduit communicating with and venting the fluid to the atmosphere whereby the passage of the fluid from the fluid source through the conduit and to the atmosphere is adapted to sufficiently raise the surface temperature of the support to effectuate ice melting. DETAILED DESCRIPTION Referring more particularly to the drawings, there is shown a garage 10 having a motor vehicle 12 therein. Adjacent the garage 10 there is a driveway 14 having a substantially rigid support surface. Imbedded under the surface of the driveway 14 there is disposed an elongated hollow conduit 16 open at each end and adapted to accommodate the flow of a fluid therethrough, such as exhaust gases from the motor vehicle 10, or in certain embodiments hot water or the like said open ends being exterior said surface. The conduit 16 is essentially a heat exchanger and placed such that maximum surface area is utilized. In the preferred embodiment the same is coiled or looped from one lateral end of the driveway to the other and again, etc. Both open ends 18, 20 of the conduit 16 are disposed at least adjacent the garage 10, and preferably within the garage 10. In the preferred embodiment a first open end 18 of the conduit 16 is disposed at least in communication with a hole or cut away portion 22 of the garage floor 24 or driveway surface 14 such that the end 18 is accessible at the hole 22. If desired, the same may be recessed in the hole 22 or the conduit 16 may exit therethrough such that the end 18 is at least proximate the hole 22. The conduit 16 itself is preferably made of a heat radiating material such as steel, aluminum, copper, etc. In communication with the conduit 16 by virtue of end 18 there will be a flexible length of tubing 26, such as flexible metal, rubber, etc. The tubing is a hollow walled member, open at both ends. A first end 28 as stated being adapted to engage conduit 16 and a second end 30 being adapted to engage the open end of the motor vehicle exhaust pipe 32. The second open end 34 of the conduit 16 may vent directly to the atmosphere or may releasably engage a vertically disposed after exhaust exit further conduit 36 that is adapted to exit the traveled exhaust fumes exterior to the garage 10 or at least away from the vehicle 12 where the same is not disposed in a garage 10. There is thus formed an elongated open ended exhaust system whereby once the vehicle engine is actuated, the exhaust fumes are not permitted to immediately vent to the atmosphere but are first channeled through the conduit 16 and only thereupon do they exit to the atmosphere. The foregoing taking advantage of the heat that is manifest in the exhaust fumes for de-icing of the driveway 14 surface. Of course, if desired, the final exit through conduit 36 may be merely adjacent the driveway and need not first be channeled back into the garage for exit therefrom. A supported vertical conduit can serve this purpose. It is to be understood, that hot water or any other suitable fluid, liquid or gas can also be channeled through the conduit and system of the invention. It is preferably designed however, for use in conjunction with a motor vehicle, such as car, truck, motorcycle, etc. Since it is obvious that numerous changes and modifications can be made in the above-described details without departing from the spirit and nature of the invention, it is to be understood that all such changes and modifications are included within the scope of the invention.
A device that is placed under the driveway surface and used in conjunction with a motor vehicle exhaust system to maintain an ice free driveway.
8
CLAIM OF PRIORITY The present application claims priority from Japanese application serial no. JP 2006-35907, filed on Feb. 14, 2006, the content of which is hereby incorporated by reference into this application. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique of recording information onto an optical disc by using laser beams, for example. 2. Description of the Related Art Optical-disc rotation control schemes generally used include two types, namely, a CLV (constant linearly velocity) control scheme, which is executed in a constant linear velocity mode, and a CAV (constant angular velocity) control scheme, which is executed in a constant angular velocity mode. In the CLV control, the optical-disc rotational velocity increases toward the inner periphery, such that it is difficult to enhance the recording/reproducing speeds by using the CLV scheme. As such, with increased recording/reproducing speeds, there is employed the CAV control scheme that enables enhancement in the linear velocity in the outer periphery portion. In addition, generally, in the case that information is recorded by using marks and spaces, the emission power and emission time of laser light are finely controlled to enhance mark-forming accuracy. Such a control scheme is called a “write strategy.” The write strategy is variable depending on the linear velocity in the event of recording onto the optical disc through the CAV control, so that the linear velocity of the optical disc is different depending on the radial position of the optical disc. For this reason, record parameters of the write strategy, such as the amounts of control of emission power and emission time of the pulse, have to be specified corresponding to the respective radial position. Further, characteristics such as those in rising and falling of recording laser light irradiated from lasers are slightly different depending on the respective laser, so that the write strategy has to be adjusted corresponds to each optical disc recording apparatus. As shown and described in Japanese Unexamined Patent Application Publication No. 2003-85753, in a CAV recording apparatus, record parameter learning is carried out on the innermost periphery and the outermost periphery, and record parameters in an inbetween radial position are obtained by interpolating, such as linear interpolation, from both learning results. Generally, however, during the manufacturing process, there occur many cases in which nonuniformity of a recording layer, distortion of optical disc recording grooves, and the like occur in outer periphery portions of the optical disc. As such, when high speed recording is carried out through the CAV scheme, there occurs a noise higher than a servo band in the outer periphery portion. Any one of the aforementioned the recording layer thickness nonuniformity and the recording groove distortion, herebelow, will be referred to as deviation. The deviation causes recording failure and reproducing failure because of servo swings in the outer periphery portion. For this reason, in the high speed CAV recording, when record parameter learning is carried out on the outer periphery portion with deviation, an inappropriate record parameter is likely to be learned to be an optimal record parameter. Especially, according to DVD-RAM standards, it is recommended that jitter corresponding to fluctuation of an edge component of a recording mark or space is set as an index in a record parameter learning scheme. As such, in the event that the S/N ratio is deteriorated due to recording failure as a result of the deviation, acquirement of the record parameters is significantly influenced, increasing the probability that an inappropriate record parameter is learned to be optimal. As a method of preventing such the problem, a method is known that calculates a record parameter being employed in the event of recording at high linear velocity on an outer periphery zone by carrying out a predetermined calculation on a record parameter obtained from the result of a trial write of an inner periphery zone (see Japanese Unexamined Patent Application Publication No. 2003-123255). SUMMARY OF THE INVENTION However, there remains a problem in that, because of influences of conditions of focus and tracking servos or the optical disc tilt, in the event of the high speed recording, the optimal record parameter cannot be obtained in the manner of prediction of the optimal record parameter through the calculation from the result of the inner periphery trial write. In addition, a problem exists with the conventional manner of the optimal record parameter prediction through the calculation from the result of the inner periphery trial write. The problem is that since a recode power margin of the optical disc is likely to decrease as the recording linier velocity increases, it is difficult to set a record power in a record power margin in the outer periphery zone in the conventional manner. In order to solve the problems described above, the present invention provides an optical information recording method for recording information onto a rewritable optical disc, which is used for information recording, in a manner that laser light is irradiated on a recording layer of the optical disc to thereby form marks thereon. The method comprises, in a zone of the optical disc where a linear velocity is low, determining an optimal recording parameter of a record wavelength at the linear velocity in accordance with a jitter value of a reproduced signal generated in a trial write; in a zone of the optical disc where the linear velocity is high, determining an optimal recording parameter of a record wavelength at the linear velocity in accordance with information obtainable from an amplitude value of a reproduced signal generated in a trial write; and determining an optimal recording parameter of a record wavelength in the event of recording information into an arbitrary address position is determined in a manner that a recording parameter is obtained through a predetermined calculation method from results of learning of optimal recording parameters on two or more zones of the optical disc where the linear velocities are different form one another. Further, the present invention provides an optical information recording method for recording information onto a rewritable optical disc, which is used for information recording, in a manner that laser light is irradiated on a recording layer of the optical disc to thereby form marks thereon. The method comprises, in a zone of the optical disc where a linear velocity is low, determining an optimal recording parameter of a record wavelength at the linear velocity in accordance with a jitter value of a reproduced signal generated in a trial write; in a zone of the optical disc where the linear velocity is high, determining an optimal recording parameter of a record wavelength at the linear velocity in accordance with information obtainable from an amplitude value of a reproduced signal generated in a trial write that is executed with a recording parameter obtained by predetermined calculation circuit from the result of learning of the recording parameter obtained in the zone where the linear velocity is low; and determining an optimal recording parameter of a record wavelength in the event of recording information into an arbitrary address position is determined in a manner that a recording parameter is obtained through a predetermined calculation method from results of learning of optimal recording parameters on two or more zones of the optical disc where the linear velocities are different form one another. The present invention further provides an optical information recording method for recording information onto a rewritable optical disc, which is used for information recording, in a manner that laser light is irradiated on a recording layer of the optical disc to thereby form marks thereon. The method comprises, in a zone of the optical disc where a linear velocity is low, determining an optimal recording parameter of a record wavelength at the linear velocity in accordance with a jitter value of a reproduced signal generated in a trial write; in a zone of the optical disc where the linear velocity is high, determining an optimal recording parameter of a record wavelength at the linear velocity in accordance with information obtainable from an amplitude value of a reproduced signal generated in a trial write that is executed with a recording parameter determined from the result of a previous trial write executed at the linear velocity on the optical disc; and an optimal recording parameter of a record waveform in the event of recording information into an arbitrary address position is determined in a manner that a recording parameter is obtained through a predetermined calculation method from results of learning of optimal recording parameters on two or more zones of the optical disc where the linear velocities are different form one another. BRIEF DESCRIPTION OF THE DRAWINGS In the accompanying drawings, FIG. 1 is a view showing an example of an apparatus configuration according to the first embodiment of the present invention; FIG. 2 is a view showing a recording pulse (pulse train) of a DVD-RAM (or, “DVD-RAM disc,” hereafter); FIG. 3 is a schematic diagram showing an example of the relationship between a record power and jitter; FIG. 4 is a diagram showing an example of the execution content of a trial write; FIG. 5 is a view showing servo misalignments on account of deviations; FIG. 6 is a schematic view showing an example of the relationship between the record power and beta value; FIG. 7 is an execution flowchart of the trial write according to the first embodiment; FIG. 8 is an execution flowchart of a trial write according to a second embodiment of the present invention; and FIG. 9 is an execution flowchart of a trial write according to a third embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described herebelow. First Embodiment A first embodiment will be described with reference to an example of a DVD-RAM disc. FIG. 1 shows the configuration of an optical information recording apparatus according to the present embodiment. With reference to the drawing, laser light emitted from a laser 108 is irradiated onto a specified radial position of an optical disc 101 , such as a DVD-RAM, through a collimate lens 105 and an objective lens 103 . Reflected light from the optical disc 101 is converged through a converging lens 106 through a beam splitter 104 , and then is converted into an electric signal (simply “signal,” hereafter) by a photoelectric transducer 107 . The signal thus obtained is decoded by demodulating circuit 111 through I/V converting circuit 109 and signal processing circuit 110 . Then, the signal is transferred to a host 115 (higher order processor) through a microcomputer 114 . Numeral 116 denotes a motor that rotational drives the optical disc in accordance with control by the microcomputer 114 . In a trial write, a reproduced signal is transferred to a trial-write information detection/processing circuit 112 from the signal processing circuit 110 . In accordance with the processing result of the trial-write information detection/processing circuit 112 , a record parameter value for setting the strategy for the laser driver 113 is determined. The trial-write information detection/processing circuit 112 is inclusive of a first parameter determining circuit, a second parameter determining circuit, and a third parameter determining circuit. These circuits will be described in detail below. In accordance with the parameter value, reproduce of a recording result and transfer thereof to the trial-write information detection/processing circuit 112 are repeated, thereby to obtain an optimal record parameter value. FIG. 2 shows an example of a record waveform of the DVD-RAM. Numeral 201 denotes a recording clock, numeral 202 denotes an NRZ (non-return to zero) signal, and numeral 203 denotes a laser emission waveform. In the trial write, position information of a record power Pw, an erase power Pe and pulse edges TSFP and TELP are optimized through record learning. According to the standards, it is recommended that the optimization be assessed from jitter between a binary recording waveform and a reproducing clock. For example, the record power Pw and the jitter (value) are interrelated as shown in FIG. 3 , and an optimal power is obtained from a curve 301 that represents the relationship between record power Pw and the jitter value. FIG. 4 shows a processing sequence of the trial write. First, learning (process) (step 401 ) of an erase power Pe and learning of a record power Pw are executed (step 402 ), and then a basic recording strategy is determined through learning of a pulse edge position (step 403 ) (“shift learning,” hereafter). Then, re-learning of the erase power Pe (step 404 ) and re-learning of the record power Pw (step 405 ) are executed, thereby to determine a record parameter. Then, the processing terminates. FIG. 5 shows a survey map of a servo waveform in during high double speed recording. In FIG. 5 , numeral 501 denotes a focus error signal, and numeral 502 denotes a tracking error signal. Numeral 503 , 504 denotes a servo signal swing resulting from deviations caused by optical disc forming. As the reproducing speed increases, the swing band proportionally increases; and when the servo swing increases greater than the servo band, it cannot be restrained through servo control. In the event that the deviation occurs in reproduce of record data of the optical disc, error is caused with binary data due to amplitude fluctuations of a reproduced signal. Thereby, the result of the trial, for example, cannot be properly assessed. Further, there are imposed adverse effects causing turbulences of the recording signal in the portion where the deviation has occurred. As such, in the event the deviation has occurred in a test zone, a record parameter determined in accordance with the result of a trial write executed therein is low in reliability. More specifically, a technique is known in which, in the CAV recording being performed on a DVD-RAM, record parameters are learned in respective drive test zones provided on an innermost periphery and an outermost periphery. For the midway portion, parameters are calculated by interpolating, such as linear interpolating, from the results of learning on the innermost periphery and the outermost periphery. However, in the CAV recording, the linear velocity on the outer periphery is higher than that on the inner periphery, such that it is likely to be influenced by the deviation, thereby to make it difficult to properly learn record parameters. As such, a technique has been proposed that obtains an outer-periphery record parameter through a predetermined calculation performed in accordance with the result of the trial write in an inner periphery. Generally, however, a record strategy is substantially analogous with the linear velocity. As such, although pulse edge position information can be obtained in the above-described technique, it is difficult to obtain an optimal record power only through the calculation because of, for example, the deviations or recording layer nonuniformity across the outer periphery zone. Further, since the recording linier velocity increases on the outer periphery, sensitivity to the record power of the recording layer of the optical disc increases, and an allowable amount (“record power margin,” hereafter) for the record power deviation decreases. From this fact also, a case can take place in which sufficient accuracy cannot be obtained only by performing the calculation of the outer-periphery record parameter in accordance with the inner-periphery learning result. Taking this problem into account, the present embodiment is made such that, in the trial write onto the outer-periphery zone where the linear velocity increases, the record power assessment is carried out without using the binary signal but with using either asymmetry information of the reproduced signal or a beta value of the reproduced signal. For example, as shown in FIG. 6 , the relationship between the record power Pw and the beta value of the reproduced signal is represented as a monotonical increase. As such, a process is carried out to obtain a beta value of the reproduced signal in the event that an outer-periphery record power value Pout 602 obtained from, for example, the result of an inner-periphery trial write through a predetermined calculation. Then, it is verified whether the beta value thus obtained falls within a range of preset, predetermined values. If the beta value does not fall within the range of predetermined beta values, then the record power is compensated for to fall within the range of beta values. FIG. 7 shows a processing sequence of record power learning in a CAV recording scheme according to the present embodiment. Operation of the processing sequence will be described herebelow. 1. Record parameter learning is started (step 701 ). 2. An inner-periphery trial write is executed with the jitter value of binary data set as the indicator (step 702 ). As a consequence, a parameter learning result B on the inner periphery is obtained with respect to a parameter initial value A on the inner periphery. 3. Through the predetermined calculation, an outer-periphery trial write result is predicted from the parameters A and B (step 703 ). As a consequence, a parameter learning result D on the outer periphery is obtained with respect to a parameter initial value C. 4. By using the second parameter determining circuit, record power verification and compensation through the outer-periphery trial write are executed with reproduced signal amplitude information (value) set as the index (step 704 ). As a consequence, a power compensation result E is obtained. 5. The record parameter learning terminates (step 705 ). In the above, any one of the asymmetry value and beta values used as the index in the outer-periphery trial write is a relative value of compression information of the reproduced signal. As such, even in the event that amplitude fluctuations of the reproduced signal is caused by the deviation or the like, the record power can be stably assessed by comparison with the assessment of the jitter value of the binary signal of the reproduced signal used in the inner periphery trial write. In addition, obtainment accuracy of the optimal record power value on the outer periphery can be improved. In accordance with the respective optimal record power values thus obtained on the inner and outer peripheries, the third parameter determining circuit obtains an optimal record parameter at arbitrary linear velocity and recording position. Thereby, well suited record quality can be attained even at arbitrary linear velocity and recording position. Second Embodiment A second embodiment of the present invention will be described herebelow. The configuration of an optical information recording apparatus according to the second embodiment is similar to the optical information recording apparatus according to the first embodiment, so that repetitious descriptions thereof are omitted herefrom. The first embodiment describes a method that performs the verification of and compensation for the record power on the outer periphery by using the values dependent on the amplitude value of the reproduced signal, more specifically, the asymmetry value and the beta value. However, for the rewritable optical disc such as the DVD-RAM, the record power Pw and the erase power Pe have to be learned. For the erase power, record quality after overwrite recording performed onto a zone where the base has been recorded has to be verified, such that it is difficult to determine the difference between the base record waveform and the overwritten record in accordance with the amplitude information values of the reproduced signal. DVD-RAM discs have a zone (disc information zone: DIZ) capable of recording drive-specific information. By recording the result of a trial write executed with an arbitrary apparatus onto a DIZ of an optical disc, the information (trial write result) recorded on the DIZ can be utilized in the case that the same optical disc is inserted into the same apparatus. As such, in the event that an unused optical disk is inserted into an optical information recording apparatus, a trial write by assessment of jitter of the binary signal is executed similarly as on the inner periphery, thereby to learn the record power Pw and the erase power Pe. In this event, also the amplitude information value, such as asymmetry or beta value, associated with the record power and erase power according to the outer-periphery learning results. These results are recorded onto the DIZ after trial write. FIG. 8 shows a processing sequence in the case where a same optical disc is inserted again into an optical information recording apparatus. The following describes the processing sequence. 1. Record parameter learning is started (step 801 ). 2. An inner-periphery trial write is executed with the jitter value of binary data set as the index (step 802 ). 3. It is verified whether the record parameter learning result obtained through a previous outer-periphery trial write is stored in the DIZ (step 803 ). 4. If stored, then the outer-periphery record parameter learning result described in the DIZ is set as an outer-periphery trial write result (step 804 ). Then, verification of the record power and the erase power and compensation through the outer-periphery trial write are executed with reproduced signal amplitude information (value), such as beta, set as the index (step 805 ). 5. If not stored (at step 803 ), similarly as in the case of the inner periphery, an outer-periphery trial write is executed with the jitter value of the binary data set as the index (step 806 ). 6. The trial write result is stored in a predetermined storing method (step 807 ). 7. The record parameter learning terminates (step 808 ). According to the processing sequence, the accurate (detailed) record power and erase power are learned in sequence 5 (step 806 ) when the optical disc has been firstly inserted into the optical information recording apparatus. Consequently, the outer-periphery erase power learning result can be easily and accurately obtained. Further, in this event, an optimal ratio (Pw-Pe ratio) between the record power can be obtained. Accordingly, in sequence 4 of learning the record power and the erase power in sequence 4 the record power and the erase power can be verified and compensated for in the manner that the beta value is verified by fixing the Pw-Pe ratio. For the predetermined storing method in sequence 6 (step 807 ), various methods can be contemplated. Employable methods include, for example, a method in which record parameters are stored into, for example, a predetermined zone of the optical disc, and the stored record parameters are read in the subsequent trial write execution. Another method is such that record parameters are stored into an internal memory of the optical information recording apparatus, the stored record parameters are read in the subsequent trial write execution. In the present embodiment, while the stored value of the previous trial write result is used in the outer-periphery trial write, the previous trial write result may be used as an initial value in the inner-periphery trial write. Thereby, the inner-periphery record power and erase power can be verified and compensated for. Third Embodiment A third embodiment of the present invention will be described herebelow. The configuration of an optical information recording apparatus according to the third embodiment is similar to the optical information recording apparatus according to the first embodiment, so that repetitious description thereof is omitted herefrom. The following described the processing sequence. 1. Record parameter learning is started (step 901 ). 2. An inner-periphery trial write is executed with the jitter value of binary data set as the index (step 902 ). 3. An initial value of an outer-periphery trial write is obtained through a predetermined calculation from the execution result of the inner periphery trial write (step 903 ). 4. It is verified whether a beta value obtained in the previous outer-periphery trial write is stored (step 904 ). 5. If stored, the stored beta value is set as an objective value (step 905 ). 6. If not stored, a predetermined beta value is set as an objective value (step 906 ). 7. In response to the objective beta value having been set, a beta value is obtained through an outer-periphery trial write, and verification of and compensation for the record power and the erase power is executed (step 907 ). 8. The beta value obtained as a result of the trial write is stored (step 908 ). 9. The record parameter learning terminates (step 909 ). For the predetermined storing method in sequence 8 (step 908 ), the same storing method as that in sequence 6 of the second embodiment can be used. According to the present embodiment, in the optical disc or the optical information recording apparatus, even when a sufficient zone capable of storing record parameters is not secured, only beta values obtained in the event of reproduce of record waveform associated with record parameters of trial write results are stored. Consequently, stabilized record parameter learning can be accomplished on outer periphery zones, and record powers and erase powers can be verified and compensated for thereby. FIG. 1 110 Signal processing circuit 111 Demodulating circuit 112 Trial-write information detection/processing circuit First parameter determining circuit Second parameter determining circuit Third parameter determining circuit 113 Laser driver 114 Microcomputer 115 Host (high order processor) FIG. 3 Jitter FIG. 4 Start Inner-Periphery Trial Write 401 Execute erase power learning in accordance with jitter error 402 Execute erase power learning in accordance with jitter error 403 Execute shift learning in accordance with jitter error 404 Execute erase power re-learning in accordance with jitter error 405 Execute record power (Pw) re-learning in accordance with jitter error Terminate Record Parameter Learning FIG. 7 701 Start record parameter learning 702 Execute inner-periphery trial write with jitter value of binary value set as index (parameter initial value=A; parameter learning result=B) 703 Predict outer-periphery trial write result through predetermined calculation from A and B (parameter initial value=C; parameter learning result=D) 704 Execute power verification and compensation through outer-periphery trial write with reproduced signal amplitude information as index (power compensation result=E) 705 Terminate record parameter learning FIG. 8 801 Start record parameter learning 802 Execute inner-periphery trial write with jitter value of binary value set as index 803 Previous outer-periphery recording condition is stored? 804 Set previous recording condition as trial write result 805 Obtain beta value through outer-periphery trial write by setting beta value according to previous recording condition to objective value, and execute verification of and compensation for record power and erase power 806 Execute outer-periphery trial write by setting jitter value of binary data to index 807 By using predetermined storing method, store recording parameter Obtained as trial write result 808 Terminate record parameter learning FIG. 9 901 Start record parameter learning 902 Execute inner-periphery trial write operation with jitter value of binary value set as index 903 Obtain initial value of outer-periphery trial write through predetermined calculation from execution result of inner-periphery trial write 904 Beta value in previous outer-periphery trial write is stored? 905 Set objective beta value from previous trial write result 906 Set predetermined value as objective beta value 907 Obtain beta value for objective beta value through outer-periphery trial write, and execute verification of and compensation for record power and erase power 908 By using predetermined storing method, store record parameter obtained as trial write result 909 Terminate record parameter learning
Means is provided that produces stabilized trial write results when, for example, servo misalignments are caused due to deviations on an optical disc that requires trial writes at high linear velocity. A recording method produces a recording parameter in the event of recording information into an arbitrary address position in the manner that a recording parameter is obtained through a predetermined calculation method from the results of learning of recording parameters on two or more zones of the optical disc where the linear velocities are different form one another. In a zone where the linear velocity is low, the method determines an optimal recording parameter from a jitter value of a reproduced signal waveform generated in a trial write. In a zone where the linear velocity is high, the method determines an optimal recording parameter in accordance with information obtainable from an amplitude value of a reproduced signal generated in a trial write.
6
FIELD OF INVENTION This invention relates to fuel injectors in general and particularly direct injection fuel injectors and more particularly to a swirl generator for generating a hollow cone fuel spray being ejected from the injector. BACKGROUND OF THE INVENTION Fuel spray preparation is very important as it provides a means to have much finer droplets of fuel being ejected into the engine. U.S. Pat. No. 5,114,077 issued on May 19, 1992 to Mark Cerny and entitled "Fuel Injector End Cap" is assigned to a common assignee, is concerned about the prevention of fuel seepage from the end cap of a high pressure injector. However, it describes a spray generator in a high pressure fuel injector. A high pressure fuel injector has the fuel at pressures exceeding 4.0 Bar. In '077 patent the spray generator is displaced adjacent and upstream from the valve seat member and has a plurality of passageways ending in an inclined passageway which directs the fuel tangential to the needle valve upstream of the sealing ring of the valve in the valve seat member. Another U.S. Pat. No. 5,207,384 issued on May 4, 1993 to John J. Horsting and entitled "Swirl Generator For An Injector" is also assigned to a common assignee. In this patent the swirl generator is located adjacent to the outlet orifice of the injector. The swirl generator is a two piece device that is located in the conical valve seat and operates to direct the fuel tangentially to the valve seat. The function of the swirl generator is to impart a tangential flow to the fuel and to minimize the amount of residual fuel in the injector prior to opening. A third patent, U.S. Pat. No. 5,271,563 issued on Dec. 21, 1993 to Cerny et al and entitled "Fuel Injector With A Narrow Annular Space Fuel Chamber" is assigned to Chrysler Corporation. This patent teaches a high pressure fuel injector wherein the fuel is directed tangentially to a volume surrounding the needle valve upstream of the valve seat. When the valve opens, this amount of fuel leaves the space and subsequent amounts of fuel are tangentially directed to the needle valve and have a swirling motion imparted to the fuel. SUMMARY OF THE INVENTION It is a principle advantage of the invention to develop a fine hollow cone shaped fuel discharged from the fuel injector. It is another advantage of the invention to control high pressure fuel flowing into the cylinder of an internal combustion engine and to do so with a resulting finely atomized fuel to increase combustion of the fuel in the cylinder. These and other advantages will become apparent from the swirl generator in a high pressure fuel injector. The high pressure fuel injector has a housing with an inlet end for receiving fuel, an outlet end for ejecting fuel into the cylinder of the engine. The injector valve body has an inlet end and an outlet end with an axially extending fuel passageway from the inlet end to the outlet end which is in fluid communication with the inlet of the housing. An armature coupled to a stator and is responsive to the energization of an electromagnetic source, being a coil wound around a bobbin and connected to an electronic control unit for axially moving in a reciprocating manner the armature along the axis of said valve body. A valve seat member is located at the outlet end of the valve body; and forms a sealing fit with the valve body either by a material to material fit or by means of a sealing member such as an 0-ring. The valve seat member has an axially extending fuel passageway; between its upstream and downstream surfaces. A needle valve is coupled to the armature and operates to open and close the fuel passageway in the valve seat member for inhibiting fuel flow therethrough. One or more metering disks form a swirl generator causing the fuel to form a hollow cone shaped fuel flow exiting from the injector. The swirl generator is connected to the upstream side of the valve seat member for providing a tangential flow path to fuel flowing from the fuel passageway in the valve body to the fuel passageway of the valve seat member. The fuel passageway of the valve seat member has a conical annulus extending between the upstream side and the downstream side of the valve seat member. A curved surface on the needle valve mates with the conical annulus on a circular band thereon. The circular band is in effect a single circumferential line on the surface for mating the needle valve and the valve seat to inhibit fuel flow through the valve seat. The band is located intermediate the upstream side of valve seat and the upstream opening of the axially extending opening in the valve seat. When the needle valve is removed from the valve seat, the very small cross sectional opening between the valve and the valve seat causes an increase in the fuel velocity which causes atomization of the fuel as it flows into the cone shaping area of the valve. These and other advantages will become apparent from the following drawings taken in conjunction with the detailed description of the preferred embodiment of the invention. BRIEF DESCRIPTION OF THE DRAWINGS In the drawings: FIG. 1 is a partial section view of a fuel injector taken along its longitudinal axis; FIG. 2 is an enlarged section view of the valve seat member including the swirl generator; FIG. 3 is a plan view of one of the metering disks; FIG. 4 is a plan view of the guide disk; and FIG. 5 is an alternate embodiment of the disk of FIG. 4. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the Figures by the characters of reference there is illustrated in FIG. 1 the longitudinal cross section of a high pressure fuel injector 10 according to the present invention. Not shown in FIG. 1 , for the purposes of clarity, is the fuel inlet with an in-line fuel filter and an adjustable fuel inlet tube which is longitudinally adjustable to vary the length of the armature bias spring. In addition, there is a connector for connecting the solenoid coil to a source of electrical potential and an O-ring for sealingly connecting the fuel inlet with a fuel rail or fuel supply member. Referring to FIG. 1, there is illustrated the plastic overmold member 12, the housing member 14, the bobbin 16 with the coil 18 wound therearound, the inlet tube or stator 20, the adjusting tube 22, the armature bias spring 24, the armature 26, the valve body shell 28, the valve body 30, the upper armature guide eyelet 32, the fuel passageway 34 through the valve body, the needle valve 36, the swirl generator 38 and the valve seat 40 in the valve seat member 42. The fuel outlet of the injector is the outlet of the fuel passageway in the valve seat. FIG. 1 illustrates a high pressure fuel injector with a swirl generator 38. The fuel injector 10 has an overmolded plastic member 12 encircling a metallic housing member 14. The housing member 14 encloses an electromagnetic source having a bobbin 16 with a coil 18 wound therearound. The ends of the coil 18 are connected through a connector to a source of electrical potential, such as an electronic control unit (ECU). At the top end of the inlet tube 20 which also functions as the stator, is an in-line filter for filtering out particles from the source of fuel. Inside the inlet tube 20 is an adjusting tube 22 which is used to adjust the fluid flow of the injector. A valve body 30 is enclosed by a valve body shell 28 and has an upper armature guide 32 eyelet on its inlet end. An axially extending fuel passageway 34 connects the inlet end of the injector with the outlet end of the valve body 30 which terminates at a valve seat member 42. Fuel flows in fluid communication between the inlet end of the housing and the valve seat member 42. The armature 26 is magnetically coupled to the inlet tube or stator 20 near the inlet end of the valve body 30. The armature 26 is guided in its reciprocal motion by the armature guide 32 eyelet and is responsive to an electromagnetic force generated by the coil 18 assembly for axially reciprocating the armature along the longitudinal axis of the valve body 30. The electromagnetic force is generated by current flow from an ECU through the connector to the ends of the coil 18 wound around the bobbin 16. The valve seat member 42 at the outlet end of the valve body 30 forms a sealing fit with the valve body 30 at the end of an axially extending fuel passageway 34 in the valve body 30. Alternatively an O-ring may be used to form the sealing function. Fuel flows in fluid communication from the fuel inlet, through the filter and along the inside of the adjusting tube 22 and the armature bias spring 24. From the spring 24 the fuel flows into the armature 26 and out an exit to the fuel passageway 34 in valve body 30. A needle valve 36 is connected or coupled to the armature 26 and operates to open and close the fuel passageway 34 in the valve seat member 42 for inhibiting fuel flow therethrough. One or more disks 44, 46 that form a swirl generator 38 are connected to the upstream side of the valve seat member 42 for providing a tangential flow path through the lower disk 46 to the valve needle 36. Fuel flows from the fuel passageway 34 to the valve seat member 42. The fuel passageway in the valve seat member 42 has a conical annulus 50 extending between the upstream side 52 and the downstream side 54 of the valve seat member 42. The needle valve has a curved surface 56, which in the preferred embodiment is a spherical surface although other surfaces may be used, for mating with the conical annulus 50 on a circular band 57 thereon. This circular band 57 lies along the conical annulus 50 or valve seat 40 intermediate the upstream side of the valve seat member 42 and the junction of the conical annulus 50 with the axially extending opening 58 in the valve seat member 42. When the curved surface 56 of the needle valve 36 mates with the circular band 57 on the conical annulus 50 fuel flow is inhibited from flowing through the valve seat 40. The axially extending opening 58 extends from the apex of the conical annulus 50 to the downstream side of the valve seat member 42. In one embodiment, this is a cylindrical surface with an edge that is a sharper rounded surface, that is a surface having a small radius. The one or more disks 44, 46 comprises an upstream or guide disk 44, shown in FIG. 4, having a plurality of angularly spaced circumferentially extending openings 60 between the perimeter of the disk 44 for supplying fluid to the downstream disk 46, and a central aperture 62 for guiding the needle valve 36. The downstream disk 46, shown in FIG. 3, has a like plurality of slots 64 extending respectively tangentially to the central aperture 63 from four openings 64 for metering the fluid, axially aligned with the openings 60 in the upstream disk, for directing and metering the fuel flow from the fuel passageway 34 to the valve seat member 42. FIG. 2 illustrates the completed swirl generator 38 mounted on the valve body member 42. The needle valve 36 is shown being guided in the central aperture 62 of the upstream disk 44. The fuel flowing from the opening 58 in the valve seat member 42 to the fuel outlet of the injector 10, exits in a hollow conical fuel stream. When the injector 10 is actuated, the fuel is fed into the swirl chamber, formed between the needle valve 36 and valve seat 40 and upstream from the circular band 57, through the tangential slots 64 it gains a high angular momentum. The fuel flow strikes the needle valve 36 upstream of the circular band 57. As the fuel continues to flow downstream along the conical annulus 50, its angular velocity increased. This increase in speed functions to atomize the fuel. The fuel then separates from the internal surface of the needle valve 36 due to boundary layer separation. The higher angular velocity combines with the wake region formed behind or downstream from the end of the needle valve 36 to create a stable air-cored vortex. The rotating fuel flows through the outlet opening 58 of the valve seat member 42 and emerges from the valve seat member in the form of an atomized hollow conical sheet of fuel. As the fuel flows through the slots 64 it forms a swirl pattern upstream from the circular band 57 when the needle valve 36 is separated therefrom in response to the reciprocal movement of the armature 26 under the influence of the coil 18. Referring to FIG. 5 there is illustrated a cup shaped guide member 68 having an axially aligned central aperture 70 for guiding the needle valve 36 in its reciprocal movement. In FIG. 1, the member 72 is a tubular member positioned to locate the upper disk 44. It is essential that the swirl generator 38 and the valve seat member 42 form a fluid tight assembly, FIG. 2, which is located against the axially extending member portion of the member 68 or 72 and is secured in the injector 10 by securing means such as laser welding. In the alternative, the one or more metering disks each have an axially aligned central aperture 63. The outer perimeter of the guide disk 44 has a diameter which is less than outside diameter of the valve seat member 42 to assist in the axial positioning of the needle valve 36 and the valve seat 40. It is important that the angularly spaced circumferentially extending openings 60 in the disks 44, 46 are axially in line and the central apertures 62 are aligned. There has thus been shown a high pressure swirl fuel injector as used in spark-ignited, direct injection gasoline engines. The function of the injector is to disintegrate the proper quantity of fuel into small drops and to discharge them into surrounding gaseous medium in the form of a symmetric uniform spray. Discharge coefficient and spray cone angle are two important characteristics of a swirl injector. The discharge coefficient determines the static flow rate. The cone angle directly affects the liquid film thickness and the extent of the spray exposure to the surrounding air. Normally, an increase in spray cone angle leads to improved atomization, better fuel-air mixing and better dispersion of the fuel drops throughout the combustion volume.
A high pressure fuel injector has a swirl generator with a metering disk upstream of the valve seat. The disks function to redirect the axially flowing fuel through the injector into a tangential fuel flow. As the fuel moves past the needle valve and the valve seat, the narrow cross section imparts a higher velocity to the fuel to atomize the fuel. As the fuel leaves the swirl generator and is ejected from the injector, the fuel forms a hollow conical sheet containing atomized fuel.
5
The invention relates to a process for preparing ciclesonide 1 (16α,17-[(R)-cyclohexylmethylenedioxy]-11β-hydroxy-21-(2-methyl-1-oxopropoxy)-pregna-1,4-dien-3,20-one) in epimerically pure form. This compound is a corticosteroid which has the following structure: Ciclesonide is used for the treatment of respiratory complaints. PRIOR ART The synthesis and purification of the active substance and particular aspects of the synthesis have already been described in different studies: DE 4129535 discloses the reaction of 11β,16α,17,21-tetrahydroxypregna-1,4-dien-3,20-one with isobutyric anhydride in pyridine to form the 16,17,21-triester and the subsequent reaction thereof with cyclohexane aldehyde in dioxane in the presence of hydrogen chloride and perchloric acid to obtain R,S-ciclesonide with R/S approx. 1:1. The reaction time for the second step is very long, at approx. 200 h. WO 94/22899 discloses the synthesis of the intermediate 16α,17-[(R,S)-cyclohexylmethylenedioxy]-11β,21-dihydroxy-pregna-1,4-dien-3,20-one by acid-catalysed reaction of 11β,16α,17,21-tetrahydroxypregna-1,4-dien-3,20-one with cyclohexane aldehyde. Depending on the reaction conditions the epimer ratio of R/S in the crude product varies between 95:5-25:75. In the majority of the Examples listed the potentially explosive 70% perchloric acid is used as catalyst and in one Example it is even used as solvent. The handling of concentrated perchloric acid has resulted in the past in numerous accidents with fatal consequences (cf. e.g. L. Roth, U. Weller-Schäferbarthold, Gefährliche Chemische Reaktionen CD-ROM, August 2011 edition, ecomed Sicherheit), i.e. the occupational handling of this substance requires particularly stringent safety precautions and is therefore costly. In some Examples, nitromethane is used as solvent, which is another explosive substance. WO 95/24416 discloses a process for concentrating the R epimer from 16α,17-[(R,S)-cyclohexylmethylenedioxy]-11β,21-dihydroxy-pregna-1,4-dien-3,20-one. Silylation in position 21, at least one fractional crystallisation and acid hydrolysis are necessary here in order to achieve a concentration of the R epimer to ≧97%. WO 98/09982 discloses the fractional crystallisation of R,S-ciclesonide from mixtures of water-miscible solvents and water. Four successive crystallisations from ethanol/water are needed in order to achieve a total yield for the epimer purification of approx. 50%—starting from an epimer ratio of R/S of approx. 90:10—to a proportion of R>99.5%. WO 02/38584 discloses the synthesis of 16α,17-[(R,S)-cyclohexylmethylenedioxy]-11β,21-dihydroxy-pregna-1,4-dien-3,20-one and R,S-ciclesonide with R/S>90:10 by reacting the corresponding 16,17-ketals with cyclohexane aldehyde in the presence of 70% perchloric acid. 1-Nitropropane is used as solvent. As already mentioned above, the use of concentrated perchloric acid has in the past resulted in a number of accidents with fatal consequences. WO 2004/085460 centres on the preparation of fine crystalline material by the addition of a solution of R,S-ciclesonide in a water-miscible solvent to water. No concentration of the R epimer is observed during this process. WO 2005/044759 relates to the synthesis of 16,17-acetals or 16,17-ketals of various pregnane derivatives by reacting the corresponding 16,17-dihydroxy compounds with aldehydes, acetals, ketones or ketals in 85% phosphoric acid. The reaction of 11β,16α,17,21-tetrahydroxypregna-1,4-dien-3,20-one with 2.5 equivalents of cyclohexane aldehyde in 4 parts of 85% phosphoric acid at 0-5° C., which is not described experimentally in WO 2005/044759, leads to a very unfavourable epimer ratio, as our own investigations have shown. After 5 h reaction and subsequent precipitation of the product by the addition of methanol and water, 16α,17-[(R,S)-cyclohexylmethylenedioxy]-11β,21-dihydroxy-pregna-1,4-dien-3,20-one is obtained with an R/S ratio of approx. 48:52. WO 2007/054974 discloses the synthesis of 16α,17-[(R,S)-cyclohexylmethylenedioxy]-11β,21-dihydroxy-pregna-1,4-dien-3,20-one and similar compounds by acid-catalysed reaction of the corresponding 16,17-ketals with cyclohexane aldehyde in mixtures of ionic liquids with acetonitrile or dichloromethane. Depending on the reaction conditions the R/S epimer ratio in the isolated product varies between 92:8-78:22. In all the Examples provided the potentially explosive 70% perchloric acid is used as catalyst. The yields are between 137-213%, i.e. the purity of the isolated crude products is rather low. WO 2007/056181 relates to the concentration of the R-epimer by crystallisation of R,S-ciclesonide from a solution containing at least one solvent that is water-immiscible. Four successive crystallisations from acetone/isooctane are needed in order to improve the R/S epimer ratio from approx. 90:10 to 99.75:0.25. Based on 45.9 g of product, more than 6137 g of acetone/isooctane are needed for the concentration process. When using dichloromethane/isooctane four crystallisations are needed to arrive at an R/S epimer ratio of 99.5:0.5, starting from an R/S epimer ratio of 90:10. Here again, a relatively large amount of solvent is used for the purification, namely more than 6000 g of dichloromethane/isooctane in relation to 37 g of product. US 2007/0117974 centres on the acid-catalysed reaction of 11β,16α,17,21-tetrahydroxypregna-1,4-dien-3,20-one with carboxylic acid anhydrides and aldehydes to obtain 16,17-acetals acylated in position 21 in the form of a one-pot reaction. In all the examples provided 70% perchloric acid is used as the acid component. The required excess of anhydride (6 equivalents) and aldehyde (4 equivalents) is comparatively high. WO 2008/015696 describes the chromatographic separation of R,S-ciclesonide into the two epimers using a chiral stationary phase. In all the examples a highly dilute solution is applied to the stationary phase (500 ppm, i.e. 1 g of epimer mixture dissolved in 2000 g solvent). WO 2008/035066 relates to the acid-catalysed reaction of 11β,16α,17,21-tetrahydroxypregna-1,4-dien-3,20-one and derivatives of 11β,16α,17,21-tetrahydroxypregna-1,4-dien-3,20-one acylated in position 21 with the bisulphite adduct of cyclohexane aldehyde to form the corresponding 16,17-acetals. A disadvantage of this process is that the bisulphite adduct has to be prepared from cyclohexane aldehyde and sodium disulphite in a separate reaction step. This includes the isolation and drying of the bisulphite adduct. The reaction of acetalisation is carried out in the examples described using large amounts of 70% perchloric acid, which requires a great many safety precautions. Moreover, WO 2008/035066 describes a crystalline methanol solvate of ciclesonide, which is obtained by crystallisation of the active substance from methanol. WO 2009/112557 describes the reaction of 11β,16α,17,21-tetrahydroxypregna-1,4-dien-3,20-one, 21-acetoxy-11β,16α,17-trihydroxy-pregna-1,4-dien-3,20-one or 11β,16α,17-trihydroxy-21-(2-methyl-1-oxopropoxy)-pregna-1,4-dien-3,20-one with cyclohexane aldehyde in the presence of bromine or hydriodic acid to form the corresponding 16,17-acetals. In the synthesis of 16α,17-[(R,S)-cyclohexylmethylenedioxy]-11β,21-dihydroxy-pregna-1,4-dien-3,20-one, in the first processing step the reaction mixture based on 1 g of 11β,16α,17,21-tetrahydroxypregna-1,4-dien-3,20-one used is added to 50 g of ice water, i.e. it is highly diluted. A disadvantage of the methods of synthesis known in the art is that they are either only partly or not at all designed for large-scale industrial production and the special requirements in terms of the production of ciclesonide on a large scale have not been sufficiently taken into account. Looking at the aspects of safety at work, scale-up capability and use of resources (in terms of raw materials) it becomes clear that the prior art has not hitherto described any process that addresses these points adequately. The present invention is thus based on providing an improved method of synthesis, particularly for use on an industrial scale, which enables pure ciclesonide to be produced safely and efficiently. The advantages of the present process are: use of a stable salt of isobutyric acid instead of hydrolysis-prone isobutyric acid derivatives such as e.g. isobutyric anhydride or isobutyric acid chloride. depletion of the 22S-epimer is possible at the 21-bromo-16α,17-cyclohexylmethylenedioxy-11β-hydroxypregna-1,4-dien-3,20-one stage. no perchloric acid and nitroalkanes are used in the preparation of ciclesonide. high total yield: by way of example mention may be made here of the total yield obtained with mixture A in Examples 1-6 (cf. the Experimental Section), which is approx. 38% starting from 11β,16α,17,21-tetrahydroxypregna-1,4-dien-3,20-one. DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a process for preparing ciclesonide of formula 1, characterised in that a compound of formula 2 wherein R 1 may denote Br, I or Cl, is reacted with a salt of formula wherein X + denotes alkali metal ions, preferably selected from among Li + , Na + , K + and Cs + , preferably Na + ; or N(R 2 ) 4 + , wherein R 2 denotes C 1-6 -alkyl, preferably selected independently of one another from among methyl, ethyl, n-propyl, n-butyl and tert-butyl, preferably methyl and n-butyl. Preferably, in the above process, R 1 in the compound of formula 2 denotes Br. Preferably, in the above process, X + denotes Li + , Na + , K + or Cs+, preferably Na + . Preferably in the above process, X + denotes N(R 2 ) 4 and R 2 may be selected independently of one another from among methyl, ethyl, n-propyl, n-butyl and tert-butyl, preferably methyl and n-butyl. Solvents that may be used for the above-mentioned reaction step include polar aprotic solvents [e.g. dimethylsulphoxide (DMSO), N-methyl-2-pyrrolidone (NMP), N-ethyl-2-pyrrolidone (NEP), dimethylformamide (DMF) and dimethylacetamide (DMAC)], polar ethers [e.g. tetrahydrofuran (THF), dioxane], polar nitriles (e.g. acetonitrile) and polar ketones (e.g. acetone). Preferred solvents for the reaction are dimethylsulphoxide, N-methyl-2-pyrrolidone, dimethylfomamide or mixtures thereof. In one embodiment of the invention the above-mentioned reaction of compound 2 to obtain compound 1 is carried out at a reaction temperature of 20-70° C., preferably 35-55° C. Preferably, in the above process, after the reaction has taken place the compound of formula 1 is purified by one or more, preferably one, two or three crystallisations from an alcoholic solvent, preferably ethanol or methanol/ethanol mixtures. A preferred variant of the purification is a single or repeated crystallisation from a methanol/ethanol mixture with the preferred ratio between 2:1 and 1:2, preferably about 1:1, followed by crystallisation from ethanol. Preferably, in the above process, the compound of formula 2, wherein R 1 denotes Br, is prepared by regioselective bromination of the compound of formula 3, Preferably in the above process the regioselective bromination of the compound of formula 3 is carried out with a catalytic variant of the Appel reaction (cf. J. Org. Chem. 2011, 76, 6749-6767 and Chem. Eur. J. 2011, 17, 11290-11295); with phosphorus tribromide (PBr 3 ), with bromotriphenylphosphonium bromide (BrPPh 3 Br) or with mixtures of organic triphenylphosphines, preferably PPh 3 , and an agent selected from among N-bromosuccinimide (NBS), tetrabromomethane (CBr 4 ), hexabromoacetone (CBr 3 COCBr 3 ), dibromo-Meldrum's acid (5,5-dibromo-2,2-dimethyl-4,6-dioxo-1,3-dioxane) and bromine (Br 2 ), preferably with BrPPh 3 Br or with mixtures of triphenylphosphine and a brominating agent selected from among N-bromosuccinimide, tetrabromomethane, hexabromoacetone and Br 2 , particularly N-bromosuccinimide. Preferably in the above process the regioselective bromination of the compound of formula 3 is carried out in a solvent selected from among halohydrocarbons, nitriles and mixtures of halohydrocarbons and nitriles. Examples of nitriles might be: acetonitrile and propionitrile. Examples of halohydrocarbons might be: dichloromethane, 1,2-dichloroethane and chloroform. Preferably in the above process the regioselective bromination of the compound of formula 3 is carried out in a solvent selected from among dichloromethane, acetonitrile and dichloromethane/acetonitrile mixtures. In the bromination with N-bromosuccinimide (NBS)/triphenylphosphine (PPh 3 ) the use of 1 to 2 equivalents of the NBS/PPh 3 mixture in relation to the educt is preferred. It is particularly preferable to use 1.2 to 1.5 equivalents of the NBS/PPh 3 mixture. It has been found that for the NBS/PPh 3 mixture a ratio of 1:1 or a small excess of NBS over PPh 3 is advantageous. The excesses of NBS and PPh 3 may, however, also be of different sizes according to the invention (e.g. 1.25 eq. NBS:1.25 eq. PPh 3 ; 1.35 eq. NBS:1.35 eq. PPh 3 ; 1.45 eq. NBS:1.45 eq. PPh 3 ; 1.50 eq. NBS:1.50 eq. PPh 3 ; 1.35 eq. NBS:1.20 eq. PPh 3 ; 1.35 eq. NBS:1.25 eq. PPh 3 ; 1.45 eq. NBS:1.25 eq. PPh 3 ; 1.50 eq. NBS:1.30 eq. PPh 3 ; 1.50 eq. NBS:1.35 eq. PPh 3 ). Preferably, the above process is characterised in that the compound of formula 2, wherein R 1 denotes Br, is purified after the reaction by one or more, preferably one or two, crystallisations from a polar, water-miscible, organic solvent or mixtures thereof, with or without the addition of water; preferred are mixtures of solvents selected independently of one another from among methanol, ethanol, isopropanol, acetonitrile, N-methyl-2-pyrrolidone (NMP), N-ethyl-2-pyrrolidone (NEP), dimethylformamide (DMF), dimethylacetamide (DMAC), dimethylsulphoxide (DMSO), acetone, methylethylketone (MEK), tetrahydrofuran (THF), dioxane, or other water-miscible ethers and water; preferred are mixtures of solvents selected independently of one another from among methanol, acetonitrile, NMP, NEP, DMSO, acetone, THF, MEK and water; preferred are mixtures of solvents selected independently of one another from among methanol, acetonitrile, NMP, DMSO, acetone and water. In one embodiment according to the invention the mixtures of solvents consist of two or three, preferably two solvents of the examples mentioned above. In one embodiment according to the invention of the above process for preparing the compound of formula 2 wherein R 1 denotes Br, after the reaction, for purification there is a) a first crystallisation from a polar, water-miscible organic solvent or mixtures thereof, with or without the addition of water; preferably mixtures of solvents are used selected independently of one another from among methanol, acetonitrile and water; followed by b) at least one purification by suspension in a polar, water-miscible organic solvent or mixtures thereof, with or without the addition of water; preferably mixtures of solvents are used selected independently of one another from among acetonitrile, NMP, NEP, DMF, DMAC, DMSO, acetone, MEK, THF, dioxane or other water-miscible ethers and water, preferably acetonitrile, NMP, NEP, DMF, DMAC, DMSO, acetone, MEK, THF and water, preferably acetonitrile, NMP, DMSO, acetone and water. If necessary, step b) may be repeated until the R epimer has been suitably concentrated. Preferably, there is a proportion of more than 95%, preferably 96%, preferably 97% of the R epimer in the product mixture of the compound of formula 2, wherein R 1 denotes Br. Step b) may be carried out selectively at low temperatures (e.g. ambient temperature) or high temperatures (boiling point). Preferably, the temperature is between 40° C. and boiling point, preferably between 45 and 80° C., depending on the boiling point of the solvent or mixture of solvents used. In one embodiment according to the invention the mixtures of solvents in steps a) and b) consist of two or three, preferably two solvents of the examples mentioned therein. Preferably in the above process the compound of formula 3 is obtained by a reaction of the compound of formula 4 with cyclohexane aldehyde in the presence of an acid, preferably methanesulphonic acid. The use of acids as catalyst and suitable solvents in the reaction of a compound of formula 4 with cyclohexane aldehyde has already been described in WO 94/22899, to which reference is hereby made in its entirety. Preferably in the above process the product of formula 3 is not isolated but reacted further directly to form a compound of formula 2. TERMS AND DEFINITIONS USED Compound 1 within the scope of the invention denotes ciclesonide or 16α,17-[(R)-cyclohexylmethylenedioxy]-11β-hydroxy-21-(2-methyl-1-oxopropoxy)-pregna-1,4-dien-3,20-one: The term R,S-ciclesonide within the scope of the invention denotes 16α,17-[(R,S)-cyclohexylmethylenedioxy]-11β-hydroxy-21-(2-methyl-1-oxopropoxy)-pregna-1,4-dien-3,20-one: The partial term “R,S” in the name of R,S-ciclesonide and 16α,17-[(R,S)-cyclohexylmethylenedioxy]-11β-hydroxy-21-(2-methyl-1-oxopropoxy)-pregna-1,4-dien-3,20-one denotes that it is an epimer mixture (mixture of diastereomers), but the ratio of epimers cannot be inferred from this, i.e. “R,S” does not mean that there has to be an epimer ratio of R/S 1:1. Compound 2 within the scope of the invention denotes 21-bromo-16α,17-[(R)-cyclohexylmethylenedioxy]-11β-hydroxypregna-1,4-dien-3,20-dione. Compound 3 within the scope of the invention denotes 16α,17-[(R)-cyclohexylmethylenedioxy]-11β,21-dihydroxy-pregna-1,4-dien-3,20-one. Unless otherwise stated, all the substituents are independent of one another. If for example a plurality of C 1-6 -alkyl groups were to be present as substituents on one group, then, in the case of three C 1-6 -alkyl substituents, they could independently of one another represent one methyl, one n-propyl and one tert-butyl. Unless stated otherwise, in organic compounds the groups R n , wherein n is a placeholder for a means for distinguishing different groups R, replace the hydrogen atoms that are not usually shown. If a group R n in a formula is given as a substituent of a carbon atom, this group R n may replace one or more hydrogen atoms, depending on the definition. Thus, for example, in the following formula by way of example the group R n may denote OH and hence the formula itself may denote 2-propanol. However, if the group R n denotes O or, written another way, ═O, two hydrogen atoms are replaced and the formula itself denotes acetone in this example. Also included in the subject-matter of this invention are the compounds according to the invention, including the salts thereof, wherein one or more hydrogen atoms, for example one, two, three, four or five hydrogen atoms, are replaced by deuterium. By an “organic solvent” is meant within the scope of the invention an organic, low-molecular substance which may dissolve other organic substances by a physical method. A prerequisite for suitability as a solvent is that during the dissolving process neither the dissolving substance nor the dissolved substance may change chemically, i.e. the components of the solution may be recovered in their original form by physical methods of separation such as distillation, crystallisation, sublimation, vaporisation or adsorption. For various reasons not only the pure solvents but also mixtures that combine the dissolving properties may be used. Examples include: alcohols (alcoholic solvents), preferably methanol, ethanol, propanol, butanol, octanol, cyclohexanol; glycols, preferably ethyleneglycol, diethyleneglycol; ethers/glycolethers, preferably diethyl ether, methyl-tert-butylether, dibutylether, anisol, dioxane, tetrahydrofuran, mono-, di-, tri-, polyethyleneglycolether; ketones, preferably acetone, butanone, cyclohexanone; esters, preferably acetic acid esters, glycolesters; amides, including nitrogen compounds, preferably dimethylformamide, pyridine, N-methyl-2-pyrrolidone, acetonitrile; nitro compounds, preferably nitrobenzene; halohydrocarbons, preferably dichloromethane, chloroform, tetrachloromethane, trichlorethene, tetrachlorethene, 1,2-dichloroethane, chlorofluorocarbons; aliphatic or alicyclic hydrocarbons; aromatic hydrocarbons, preferably benzene, toluene, o-xylene, m-xylene, p-xylene; or corresponding mixtures thereof. By the term “C 1-6 -alkyl” (including those that are part of other groups) are meant branched and unbranched alkyl groups with 1 to 6 carbon atoms and by the term “C 1-4 -alkyl” are meant branched and unbranched alkyl groups with 1 to 4 carbon atoms. Alkyl groups with 1 to 4 carbon atoms are preferred. Examples include: methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, sec-butyl, tert-butyl, n-pentyl, iso-pentyl, neo-pentyl or hexyl. The abbreviations Me, Et, n-Pr, i-Pr, n-Bu, i-Bu, t-Bu, etc. may optionally also be used for the above-mentioned groups. Unless stated otherwise, the definitions propyl, butyl, pentyl and hexyl include all the possible isomeric forms of the groups in question. Thus, for example, propyl includes n-propyl and iso-propyl, butyl includes iso-butyl, sec-butyl and tert-butyl etc. In purification by “suspension” a crude product obtained in solid form is stirred with a suitable solvent and washed out. The solvent is suitable, under the conditions selected, for dissolving impurities from the crude product, but dissolves the product itself only to a very minor extent or ideally not at all. However, should some of the product become dissolved, it can usually be recovered analogously to a purification by recrystallisation by cooling the solution. In principle, the same solvents may be used for the suspension as are used for purification by recrystallisation, but because of the small amounts used or the fact that the temperature is too low they are not capable of dissolving the product completely. After washing out, the suspension is filtered to recover the product. EXPERIMENTAL SECTION Example 1 Preparation of Compound 3 (Concentrate) Mixture A: 100 g of 11β,16α,17,21-tetrahydroxypregna-1,4-dien-3,20-one are suspended in 2 l of dichloromethane, cooled to −20° C. and 37 g cyclohexane aldehyde are added with stirring. Then 255 g of methanesulphonic acid are added within 30 min at this temperature. The solution thus obtained is stirred for 3 h at −20° C. The reaction solution is combined with a mixture of 160 ml of 45% sodium hydroxide solution and 500 ml of water at max. 10° C. and then adjusted to a pH of 8.5 with 100 ml of 5% sodium hydrogen carbonate solution. The phases are separated from one another and the aqueous phase is extracted once with 500 ml dichloromethane. The combined organic phases are washed once with 500 ml of water and then concentrated down to a volume of 900 ml. Mixture B: 255 g methanesulphonic acid are added to a mixture of 100 g of 11β,16α,17,21-tetrahydroxypregna-1,4-dien-3,20-one, 2 l of dichloromethane and 37 g of cyclohexane aldehyde at −10 to −15° C. within 30 min. The solution is stirred for 3 h at −15° C. and then adjusted to pH 8 with approx. 10% sodium hydroxide solution, the phases are separated from one another and the aqueous phase is extracted once with 500 ml of dichloromethane. The combined organic phases are washed once with 500 ml of water and then concentrated to a total volume of 900 ml. Mixture C: 25 g of 11β,16α,17,21-tetrahydroxypregna-1,4-dien-3,20-one and 500 ml of dichloromethane are taken and first 9 g cyclohexane aldehyde are added quickly at −15° C. and then a total of 64 g methanesulphonic acid are added at −18 to −20° C. within 30 min, with stirring. After approx. 3 h at −20° C. the reaction solution is adjusted to a pH of 2.5 with a mixture of 40 ml of 45% sodium hydroxide solution and 125 ml of water and then to a pH of 8.5 with 25 ml of 5% sodium hydrogen carbonate solution. The phases are separated from one another and the aqueous phase is extracted once with 125 ml of dichloromethane. The combined organic phases are washed once with 125 ml of water and concentrated in vacuo to a volume of 225 ml. Mixture D: 700 g of 11β,16α,17,21-tetrahydroxypregna-1,4-dien-3,20-one and 7 l of dichloromethane are placed in a 25 l reactor. The suspension is cooled to −15° C. with stirring and at this temperature 258 g cyclohexane aldehyde are metered in. Within 30 minutes 1790 g of methanesulphonic acid are added and the resulting solution is stirred for 160 min at −15° C. The reaction mixture is adjusted at max. 10° C. to a pH of 1.8 with a solution of 1.1 l of 45% sodium hydroxide solution and 5.8 l water and then adjusted to a pH of 8.0 with a 5% sodium hydrogen carbonate solution. The phases are separated from one another and the aqueous phase is extracted once with 3.7 l of dichloromethane. Then the combined organic phases are washed once with 3.5 l of water and the product solution is evaporated down to a volume of 5 l under a pressure of approx. 600 mbar and a jacket temperature of max. 50° C. Mixture E: 700 g of 11β,16α,17,21-tetrahydroxypregna-1,4-dien-3,20-one and 7 l of dichloromethane are placed in a 25 l stirred apparatus. The contents of the apparatus are cooled to −15° C. with stirring and 258 g of cyclohexane aldehyde are added. Then within 30 minutes 1790 g methanesulphonic acid are metered in and the resulting solution is stirred for a further 210 min at −15° C. The reaction mixture is combined with a solution of 1.1 l of 45% sodium hydroxide solution and 5.8 l of water at max. 10° C. and then adjusted to a pH of 8.0 with 1.8 l of a 5% sodium hydrogen carbonate solution. The phases are separated and the aqueous phase is extracted once with 3.5 l dichloromethane. The combined organic phases are washed once with 3.5 l of water and some of the solvent is distilled off at a pressure of approx. 600 mbar and a jacket temperature of max. 50° C. 5 l of compound 3 concentrate are obtained. Mixture F: 15 g cyclohexane aldehyde are added to a suspension of 40 g of 11β,16α,17,21-tetrahydroxypregna-1,4-dien-3,20-one in 400 ml dichloromethane and the mixture is cooled to −17° C. At this temperature 102 g methanesulphonic acid are metered in with stirring within 35 min. The resulting solution is stirred for a further 3 h, and at the end of the stirring time the temperature is 0° C. The reaction mixture is neutralised with a solution of 64 ml of 45% sodium hydroxide solution and 200 ml of water and then adjusted to a pH of 7.8 with approx. 5 ml of 5% sodium hydrogen carbonate solution. The phases are separated from one another, the aqueous phase is extracted once with 100 ml of dichloromethane and then the combined organic phases are washed once with 100 ml of water. The combined organic phases are worked up in mixture H of Example 2. Example 2 Preparation of Compound 2 (Crude) Mixture A: 300 ml of the concentrate of compound 3 (from Example 1, mixture A) are diluted with 480 ml of dichloromethane. 35 g of triphenylphosphine are added with stirring under an inert gas atmosphere and the solution is cooled to 10° C. In a temperature range from 10 to 16° C., 24 g of N-bromosuccinimide (NBS) are added batchwise within 1 h. After another hour the reaction mixture is evaporated to dryness, 50 ml of methanol are added and the mixture is evaporated to dryness again. Then the residue is taken up in 760 ml of methanol, 40 ml of water are added, the mixture is heated to 50° C. and stirred for 1 h. The resulting suspension is allowed to return slowly to ambient temperature. It is stirred for a further 16 h and the suspension is filtered through a suction filter. The solid separated off is washed twice with 25 ml of methanol/water 95:5 and twice with 25 ml of methanol and then dried at 60° C. in the vacuum dryer. 35 g compound 2 are obtained in crude form. Chromatographic purity (HPLC-UV): 93.5% fl. R epimer, 5.5% fl. S epimer. Mixture B: 35 g of triphenylphosphine are added to 300 ml of the concentrate of compound 3 (from Example 1, mixture A) with stirring under an inert gas atmosphere, the mixture is cooled to 10° C. and then a solution of 24 g of N-bromosuccinimide in 480 ml acetonitrile is metered in at 10 to 16° C. within 1 h. After 1 h reaction time the reaction mixture is evaporated to dryness at 40° C. in vacuo, 50 ml of methanol are added and the mixture is evaporated to dryness once more. The remaining residue is taken up in 500 ml of methanol, combined with 26 ml of water and heated to 50° C. At this temperature it is stirred for 1 h, during which time the product begins to precipitate out. After cooling to ambient temperature the suspension is stirred for a further 16 h. The precipitate separated off by vacuum filtration is washed twice with 25 ml of methanol/water 95:5 and twice with 25 ml of methanol. After drying at 60° C. in the vacuum dryer 36 g of the product is obtained. Chromatographic purity (HPLC-UV): 92.9% fl. R epimer, 5.6% fl. S epimer. Mixture C: 450 ml of the concentrate of compound 3 (from Example 1, mixture B) and 52 g triphenylphosphine are taken at 15° C., a solution of 66 g tetrabromomethane in 660 ml dichloromethane is metered in within 90 min and the mixture is stirred for another 30 min at 15 to 20° C. The reaction mixture is evaporated to dryness in vacuo at 40° C., 50 ml of methanol are added and the solvent is distilled off once more. The residue is dissolved in 760 ml of methanol, combined with 40 ml of water and stirred for several hours at ambient temperature. The resulting suspension is cooled to 10° C. After 2 h at 10° C. the precipitated solid is separated off using a filtration device, washed with 100 ml of methanol and dried at 60° C. in the vacuum dryer. 50 g product are obtained. Chromatographic purity (HPLC-UV): 89.5% fl. R epimer, 7.9% fl. S epimer. Mixture D: 450 ml of the concentrate of compound 3 (from Example 1, mixture B) are placed under an inert gas atmosphere and at 10° C. a suspension of 73 g bromotriphenylphosphonium bromide in 660 ml dichloromethane is added batchwise within 90 min. After the addition has ended the reaction mixture is stirred for another 30 min and then evaporated to dryness in vacuo. 50 ml of methanol are added to the residue and again the mixture is evaporated to dryness. The residue is taken up in a mixture of 760 ml of methanol and 40 ml of water, the resulting suspension is stirred first for several hours at ambient temperature, then cooled to 10° C. and stirred for another 2 h at 10° C. The precipitate separated off by suction filtering is washed with 100 ml of methanol and dried at 60° C. in the vacuum dryer. The yield is 45 g. Chromatographic purity (HPLC-UV): approx. 88.3% fl. R epimer, approx. 5.1% fl. S epimer. Mixture E: the concentrate of compound 3 (225 ml) obtained from mixture C of Example 1 and 26 g triphenylphosphine are placed at 10° C. under an inert gas atmosphere and a solution of 18 g of N-bromosuccinimide in 480 ml dichloromethane is added with stirring at 10 to 16° C. within 1 h. After 1 hour's reaction the solvent is distilled off in vacuo at 40° C., the residue is combined with 50 ml of methanol and the solvent is distilled off again. The residue is taken up in 760 ml of methanol with gentle heating and combined with 40 ml of water. The resulting suspension is stirred for 1 h at 50° C. Then it is allowed to come up to ambient temperature and stirred for a further 16 h. The solid is separated off by vacuum filtration, washed twice with 25 ml of methanol/water 95:5 and twice with 25 ml of methanol and then dried at 60° C. in the vacuum dryer. 25 g product are obtained. Chromatographic purity (HPLC-UV): 93.8% fl. R epimer and 4.8% fl. S epimer. Mixture F: 730 g of triphenylphosphine and 5 l of dichloromethane are added to the concentrate of compound 3 (5 l) obtained from mixture D of Example 1, with stirring, under an inert gas atmosphere, and the solution is cooled to 5° C. At 5 to 10° C., 496 g of N-bromosuccinimide are added in five batches within 1 h and stirred for a further 3 h. In the course of the second stirring period the reaction mixture is slowly heated from 10° C. to 20° C. and then the solvent is distilled off in vacuo at a jacket temperature of max. 50° C. The distillation residue is suspended in 1.4 l of methanol, the solvent is distilled off again in vacuo and then 10.5 l of methanol and 0.56 l of water are added. The resulting suspension is cooled from 40° C. to 20° C. within 2 h, stirred for a further 16 h at 20° C. and then added through a pressure filter. The filter cake obtained is washed with 0.70 l of methanol/water 95:5 and 0.70 l of methanol and then dried at 60° C. in vacuo. 660 g of compound 2 are obtained in crude form. Chromatographic purity (HPLC-UV): 91.9% fl. R epimer, 6.6% fl. S epimer; drying loss (80° C.): 0.3%. Mixture G: the concentrate of compound 3 (5 l) obtained from mixture E of Example 1, 658 g of triphenylphosphine and 5 l of dichloromethane are placed in a 25 l reactor. The reactor contents are cooled to 5° C., 446 g of N-bromosuccinimide are added batchwise within 1 h at 5 to 10° C., the mixture is kept for 1 h at 10° C. and the reaction mixture is then allowed to come up to 20° C. within 3 h. The solvent is distilled off in vacuo at max. 50° C. jacket temperature, 1.4 l of methanol are added to the residue and it is distilled again. The residue remaining in the reactor is taken up in 10.5 l of methanol and 0.56 l of water and slowly cooled from 40° C. to 20° C. The resulting suspension is stirred for another 21 h at 20° C. and then the precipitate is isolated using a pressure filter. The precipitate is washed first with 0.70 l of methanol/water 95:5 and then with 0.70 l of methanol. After drying at 50° C. in vacuo, 740 g of the product is obtained. Chromatographic purity (HPLC-UV): 92.2% fl. R epimer, 6.5% fl. S epimer; drying loss (80° C.): 1.9%. Mixture H: The combined organic phases from Mixture F of Example 1 are evaporated to dryness in vacuo, the non-volatile constituents are combined with 200 ml of acetonitrile and evaporated to dryness again at 40 to 50° C. The residue remaining is taken up in 500 ml acetonitrile and at 50° C., with stirring, 42 g triphenylphosphine and a further 250 ml acetonitrile are added under an inert gas atmosphere. The mixture is cooled to 2° C. and at this temperature 29 g of N-bromosuccinimide are added in 15 batches within 70 min. The mixture is stirred for another 3 h at 2 to 3° C. and allowed to come up to 12° C. within 90 min. The reaction mixture is evaporated down to a volume of approx. 260 ml and 13 ml of water are added at 45° C. After cooling to ambient temperature the resulting suspension is stirred for 16 h and then subjected to vacuum filtration. The isolated precipitate is washed twice with 50 ml acetonitrile and then dried at 60° C. in vacuo. 32 g of compound 2 are obtained in crude form. Chromatographic purity (HPLC-UV): 94.6% fl. R epimer, 4.2% fl. S epimer. Example 3 Purification of Compound 2 (Crude) to Compound 2 (Industrial Grade) Mixture A: 30 g of crude compound 2 (from Example 2, Mixture A) are suspended in a mixture of 588 ml of acetonitrile and 12 ml of N-methyl-2-pyrrolidone (NMP). The suspension is heated to 80° C. with stirring and kept for 1 h at this temperature. After slow cooling to 5° C. the mixture is kept for 16 h at this temperature and then added through a Büchner funnel. The precipitate separated off is washed with 50 ml of acetonitrile previously adjusted to a temperature of 5° C., and dried at 60° C. in vacuo. 23 g of industrial grade compound 2 are left. Chromatographic purity (HPLC-UV): 97.0% fl. R epimer, 2.7% fl. S epimer. Mixture B: 250 g of crude compound 2 [chromatographic purity (HPLC-UV): approx. 91.9% fl. R epimer, approx. 5.8% fl. S epimer] are suspended in a mixture of 4.9 l of acetonitrile and 0.10 l of N-methyl-2-pyrrolidone, heated to 80° C. with stirring and kept for 1 h at this temperature. Then it is slowly cooled to 20° C. and the suspension is stirred for several hours at this temperature. It is then cooled to 5° C. and stirred for 1 h at this temperature. The solid is separated off through a suction filter, washed with 0.20 l of acetonitrile and dried for approx. 15 h in the vacuum dryer at 60° C. 195 g of product are obtained. Chromatographic purity (HPLC-UV): 95.8% fl. R epimer, 3.3% fl. S epimer. Mixture C: 25 g of crude compound 2 [chromatographic purity (HPLC-UV): 89.6% fl. R epimer, 7.2% fl. S epimer] are combined with 500 ml of acetonitrile/dimethylsulphoxide 98:2 and stirred for 1 h at 80° C. The mixture is slowly cooled to 20° C. and then stirred for another 16 h at this temperature. The precipitate is filtered off through a Büchner funnel, washed with 25 ml of acetonitrile and dried for 20 h at 60° C. in vacuo. The yield is 20 g. Chromatographic purity (HPLC-UV): 95.2% fl. R epimer, 3.3% fl. S epimer. Mixture D: a suspension of 212 g of crude compound 2 [chromatographic purity (HPLC-UV): approx. 92.2% fl. R epimer and approx. 4.7% fl. S epimer), 1000 ml of acetone and 50 ml of water is stirred for 2 h at 50° C. It is then allowed to come up to ambient temperature and stirred for several more hours at ambient temperature. The precipitate separated off is washed with 200 ml of acetone/water 90:10 and then dried for 20 h at 60° C. in the vacuum dryer. 163 g of product are obtained. Chromatographic purity (HPLC-UV): 97.4% fl. R epimer, 1.4% fl. S epimer. Example 4 Preparation of Crude Ciclesonide Mixture A: A mixture of 22 g of industrial-grade compound 2 (from Example 3, mixture A), 110 ml of DMSO and 6 g of sodium isobutoxide is heated to 40° C. with stirring. After 90 min the resulting reaction solution is allowed to cool to approx. 20° C. and 176 ml of methyl-tert-butylether (MtBE) and 110 ml of water are added. The mixture is stirred vigorously for 10 min, the organic and the aqueous phase are separated from one another and the aqueous phase is discarded. The organic phase is washed three times with 60 ml of water, evaporated to dryness in vacuo, 10 ml of ethanol are added and the mixture is again evaporated to dryness. Then the residue remaining is dissolved in 33 ml of ethanol at approx. 60° C., combined with 33 ml of methanol and slowly cooled to 0° C. The suspension is stirred for 3 h at 0° C. The precipitate is separated off by suction filtering, washed with 66 ml of cold methanol and dried at 70° C. in the vacuum dryer. 20 g of crude ciclesonide are obtained. Chromatographic purity (HPLC-UV): 98.8% fl. R epimer, 0.9% fl. S epimer. Mixture B: 194 g of industrial-grade compound 2 (from Example 3, mixture B) are placed in 970 ml of dimethylsulphoxide (DMSO) at ambient temperature and 55 g of sodium isobutoxide are added with stirring. The reaction mixture is heated to 40° C., kept for 80 min at this temperature and then cooled to ambient temperature. After the addition of 1550 ml of methyl-tert-butylether and 970 ml of water the resulting 2-phase system is vigorously stirred for 10 min. After phase separation has been carried out the organic phase is washed three times with 530 ml of water and then the solvent is distilled off in vacuo. The residue remaining is taken up in 90 ml of ethanol and the solvent is distilled off again. The residue is dissolved at 60° C. in 290 ml of ethanol and combined with 290 ml of methanol. It is slowly allowed to return to ambient temperature and stirred for 15 h at this temperature. The suspension is cooled to 0° C. and kept for 2 h at this temperature. The solid is then separated off by vacuum filtration, washed with 580 ml of cold methanol and then suction filtered dry. 183 g of solid are obtained. Chromatographic purity (HPLC-UV): 98.5% fl. R epimer, 1.1% fl. S epimer; drying loss (70° C.): 2%. Mixture C: 40 g of industrial-grade compound 2 [chromatographic purity (HPLC-UV): 93.4% fl. R epimer, 2.9% fl. S epimer] are dissolved in 220 ml of N-methyl-2-pyrrolidone and 11 g of sodium isobutoxide are added at ambient temperature. The reaction mixture is heated to 50° C., kept for 3 h at this temperature and then cooled to ambient temperature. 300 ml of methyl-tert-butylether and 200 ml of water are added and a high stirring speed is selected for 10 min. After separation of the two phases the aqueous phase is discarded. The organic phase is washed three times with 100 ml of water and evaporated to dryness in vacuo. The residue is taken up in 60 ml of ethanol in the warm, briefly distilled in vacuo, 60 ml of methanol are added and the mixture is left to cool slowly to ambient temperature. The resulting suspension is stirred for several hours at ambient temperature and then for 3 h at 0° C. The precipitate separated off by suction filtration is washed once with 30 ml and once with 50 ml of cold methanol and dried for 20 h at 60° C. in the vacuum dryer. 34 g of solid are obtained. Chromatographic purity (HPLC-UV): 97.7% fl. R epimer, 0.9% fl. S epimer. Example 5 Purification of Ciclesonide (Crude) to Ciclesonide (Industrial Grade) Mixture A: the crude ciclesonide (20 g) obtained from mixture A of Example 4 is dissolved in 33 ml of ethanol at 70° C. and combined with 33 ml of methanol with stirring. The solution is cooled to 2° C. within approx. 4 h and then left to stand for 16 h at 2° C. The product that crystallises out is separated off by suction filtering. The filter cake is washed twice with 20 ml of cold methanol and then dried for 20 h at 70° C. in vacuo. 18 g of industrial-grade ciclesonide are obtained. Chromatographic purity (HPLC-UV): 99.5% fl. R epimer, 0.4% fl. S epimer. Mixture B: 181 g of crude ciclesonide (from Example 4, Mixture B) are suspended in 300 ml of ethanol at ambient temperature. During heating to 70° C. a solution is formed. 300 ml of methanol are added to this solution with stirring, it is cooled very slowly to 0° C. and the resulting crystal suspension is kept for 2 h at this temperature. The precipitate is separated off by suction filtering, the crystals are washed with 300 ml cold methanol and then suction filtered until thoroughly dry. 163 g of solid are obtained. Chromatographic purity (HPLC-UV): 99.4% fl. R epimer, 0.4% fl. S epimer; drying loss (70° C.): 2%. Example 6 Purification of Ciclesonide (Industrial Grade) to Ciclesonide (Pure) Mixture A: 170 mg of activated charcoal are added to a solution of 17 g of industrial-grade ciclesonide (from Example 5, Mixture A) which has been adjusted to a temperature of 70° C., in 24 ml of ethanol. A clear filtration is carried out and the filter residue is washed with 10 ml of ethanol. The combined filtrate is left to cool to 21° C. within 3 h. The resulting suspension is then cooled to 2° C. After 16 h at 2° C. the mixture is filtered and the precipitate is washed twice with 20 ml of cold ethanol. The isolated product is dried for 20 h at 60° C. in vacuo. The yield of pure ciclesonide is 14 g. Chromatographic purity (HPLC-UV): 99.7% fl. R epimer, 0.2% fl. S epimer; q-NMR: R epimer 99.0%; m.p.: 210° C.; water content (KF): 0.5%; ignition residue: <0.1%. Mixture B: 200 ml of ethanol are added to 160 g of industrial-grade ciclesonide (from Example 5, mixture B) and the mixture is heated to 70° C. with stirring. After the addition of 2 g activated charcoal it is filtered hot and the filter residue is washed with 115 ml of ethanol. The combined filtrate is left to cool to ambient temperature. The resulting crystal suspension is stirred for several hours at ambient temperature, cooled to 0° C. and kept for 2 h at 0° C. The crystals separated by suction filtration are washed with 160 ml of cold ethanol and then dried at 60° C. in the vacuum dryer. 129 g of pure ciclesonide are obtained. Chromatographic purity (HPLC-UV): 99.7% fl. R epimer, 0.2% fl. S epimer; m.p.: 210-211° C. Example 7 Isobutoxide Salt Screening 1 g aliquots of industrial grade compound 2 (with an epimer ratio R/S of 97.2:2.8) are dissolved in 5 ml of solvent at ambient temperature, combined with 1.4 equivalents of isobutoxide salt and stirred at 50° C. Conversion monitoring using HPLC-UV is carried out after 1 h, 2 h and 5 h. For results: see the Table. after 1 h: after 2 h: after 5 h: isobutoxide salt solvent educt/R/S* educt/R/S* educt/R/S* sodium isobutoxide NMP   0.7/97.7/1.6 <0.1/97.7/2.2 <0.1/97.1/2.8 potassium isobutoxide NMP <0.1/97.1/2.8 <0.1/97.0/2.9 <0.1/97.2/2.7 lithium isobutoxide NMP 19.9/79.5/0.6   4.0/94.8/1.2   0.1/98.0/1.9 caesium isobutoxide NMP <0.1/97.0/2.9 <0.1/97.0/2.9 <0.1/97.0/2.9 tetra-n-butylammonium NMP <0.1/96.9/3.0 <0.1/97.5/2.4 <0.1/97.6/2.3 isobutoxide tetramethylammonium isobutoxide NMP <0.1/96.9/3.0 <0.1/97.0/2.9 <0.1/97.0/2.9 sodium isobutoxide DMSO <0.1/97.3/2.6 <0.1/97.1/2.8 <0.1/97.1/2.8 *% Fl. compound 2/% Fl. ciclesonide/% Fl. 16α,17-[(S)-cyclohexylmethylenedioxy]-11β-hydroxy-21-(2-methyl-1-oxopropoxy)-pregna-1,4-dien-3,20-one
The invention relates to a process for preparing the corticosteroid ciclesonide, used for the treatment of respiratory complaints, in epimerically pure form of formula 1:
2
BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a drier apparatus and in particular to circuitry for controlling a signal device in connection with the operation of drier apparatus. 2. Description of the Prior Art In U.S. Pat. Nos. 3,365,809 of Donald F. Eppley, 3,391,467 of Samuel J. Miller, et al., 3,398,460 of Alvin J. Elders, and 3,491,458 of Alvin J. Elders et al., each of which patents is owned by the assignee hereof, a number of different drier control circuits are shown for use with clothes driers having an anti-wrinkle cycle. Additional clothes drier controls are disclosed in other U.S. Patents, such as No. 2,796,679 of Robert L. Dunkelman, No. 3,333,345 of James L. Miller, No. 3,363,326 of Edwin R. Weeks, No. 3,399,461 of Roger F. Doty, No. 3,710,138 of Curran D. Cotton, and No. 3,783,529 of James L. Miller et al. In Miller U.S. Pat. No. 3,333,345, the drier control circuit includes a buzzer controlled by a centrifugal switch of the drier motor. At the conclusion of the heated drying portion of the drier operation, a brief buzzer signal is produced when the drum temperature drops to a preselected level, with the signal being continued until the drive motor speed is reduced to a preselected low speed. In the Miller et al. U.S. Pat. No. 3,783,529, a buzzer is connected to be energized at the conclusion of any selected cycle of operation of the drier whenever the door is closed and intermittently during the duration of a no-heat portion at the end of a cycle. Manually operable switch means are provided for controlling the operation of the buzzer circuit as desired. SUMMARY OF THE INVENTION The present invention comprehends an improved control circuit for use in a drier apparatus or the like, wherein selective energization of a buzzer is effected by a cycle switch causing the buzzer to operate selectively in series with the drive motor or in parallel therewith to provide different indications of the operation of the drier. More specifically, the invention comprehends providing such an improved control circuitry wherein the cycle switch comprises a double throw switch arranged to connect the buzzer selectively in series with the drive motor and centrifugal switch and in parallel with a timed switch for normally controlling operation of the drive motor whereby de-energization of the drive motor by opening of the timed switch permits the buzzer to operate until the drive motor speed is reduced to a preselected level whereat the centrifugal switch is thrown from its normal high speed operating arrangement. Further more specifically, the cycle switch may be selectively disposed to connect the buzzer in series with the centrifugal switch and in parallel with the series connected timed switch and drive motor whereby a pulser associated with the cycle switch may cause an intermittent operation of the buzzer as during the anti-wrinkle drying cycle. The timer motor may be connected across the power supply so as to be operable independently of the drive motor. The control circuit of the present invention is extremely simple and economical of construction while yet providing the highly desirable features discussed above. BRIEF DESCRIPTION OF THE DRAWING Other features and advantages of the invention will be apparent from the following description taken in connection with the accompanying drawing wherein: FIG. 1 is a perspective view of a drier apparatus having a control circuit embodying the invention; and FIG. 2 is a schematic wiring diagram of the control circuit. DESCRIPTION OF THE PREFERRED EMBODIMENT In the exemplary embodiment of the invention as disclosed in the drawing, a drier apparatus generally designated 10 illustratively comprises a floor-mounted domestic-type clothes drier having a cabinet 11 provided with a front door 12 for front loading of clothes to be dried in the drier. The drier may include a control console 13 provided with suitable manually operable control elements, such as elements 14, for selectively controlling the operation of the drier in different modes. As discussed briefly above, the invention herein is concerned with the provision of a signal for indicating to the user different conditions of operation of the drier. More specifically, the invention comprehends the provision of signal means, which may be in the form of a signal device such as buzzer 15, for providing an audible signal to indicate to the user (a) the termination of a normal drying cycle and (b) the operation of the drier in a preselected anti-wrinkle cycle. The signal provided by the buzzer to indicate the two different conditions may be correspondingly different so as to advise the user specifically of the different conditions. More specifically as shown in FIG. 2, the drier control generally designated 16 is arranged to be connected to a three-wire power supply generally designated 17 having high voltage leads L1 and L2 and a neutral lead L3 defining, with lead L1, a low voltage supply. In the illustrated embodiment, the voltage between leads L1 and L2 is 240 volts and the voltage between leads L1 and L3 is 120 volts. The neutral lead L3 may be suitably grounded, as shown at G. The drier has drive means including a drive motor 18 for rotating the drier drum (not shown). The drive motor may be provided with a conventional start winding 19 and a run winding 20. A momentary switch such as push-to-start rotary switch 21 is connected from power supply lead L3 to the run winding 20. A common connection 22 between the start and run windings is connected through a door switch 23 and a timed switch 24 to power supply lead L1. In the "off" condition of the drier, the switch 24 may be closed so that initiation of operation of the drier may be effected by the manual closing of switch 21 thereby establishing a circuit from power supply lead L1 through closed switch 24, closed door switch 23, the parallel connection of start winding 19 and run winding 20, and switch 21 to power supply lead L3. The run and start windings are connected in parallel at this time by a centrifgal switch generally designated 25 having a moving contact 25a selectively engageable with a first fixed contact 25b connected to start winding 19, and a second fixed contact 25c connected to power supply lead L3. Thus, when the drive motor is stationary, or running at a speed less than a preselected speed, the centrifugal switch is connected as shown in FIG. 2 to connect start winding 19 in parallel with run winding 20 through switch 21 to power supply lead L3. When, however, the speed of the drive motor increases to beyond the preselected speed, moving contact 25a of the centrifugal switch is thrown from fixed contact 25b to fixed contact 25c, thereby disconnecting the start winding 19 and causing the motor to continue to run solely on the run winding 20. Such continued operation is maintained notwithstanding the release of switch 21 as the centrifugal switch now serves as a holding switch connected in parallel around the start switch 21. The switch 24 enables operation of the motor 18 during the drier cycle and terminates motor operation at the conclusion of the cycle. The switch 24, as shown in FIG. 2, is a timed switch and is controlled by a timer motor 26, which is connected through a timed switch 27 in series relationship between power supply leads L1 and L3. As further shown in FIG. 2, the timer motor is connected in series with a resistor 28 and the drier heater 29 to a second centrifugal switch 30 connected to power supply lead L2. In parallel with the series connection of timer motor 26 and resistor 28 is a series of thermostat switches, including a safety thermostat switch 31, and a pair of operating thermostat switches 32 and 33. In series with the thermostat switches is another timed switch 34 operated by the timer 26. As indicated briefly above, the invention is concerned with the control of buzzer 15 so as to provide different signals to the user corresponding to different operating conditions of the drier. As shown in FIG. 2, the control includes switch means including a cycle switch generally designated 35 for providing this desirable control of the operation of buzzer 15. The cycle switch comprises herein a single pole, double throw switch having a moving contact 35a connected to the buzzer 15, a first fixed contact 35b connected to the switch 24, and a second fixed contact 35c connected to the switch 21. The cycle switch may be manually set in either a first or second operation mode to select either a normal cycle by throwing movable contact 35a into contact with fixed contact 35b, or an anti-wrinkle cycle by throwing movable contact 35a into an electrically engageable relationship with fixed contact 35c. When thrown into engagement with fixed contact 35b, the moving contact 35a is maintained in engagement therewith during the entire drying cycle. When thrown into the engageable relationship with fixed contact 35c, the moving contact 35a is caused to intermittently make and break the connection; and, for this purpose, a pulser means which may be a conventional pulser mechanism generally designated 36 is provided. In the illustrated embodiment, the pulser mechanism causes the moving contact 35a to close with fixed contact 35c for about seven seconds at the end of approximately the first 81/2 minutes of the anti-wrinkle cycle and at 5-minute intervals thereafter during the remainder of the anti-wrinkle cycle which may be, for example, 30 minutes in duration. Thus, it can be seen that when the cycle switch 35 is arranged to engage moving contact 35a with fixed contact 35b, the buzzer is connected in parallel with timed switch 24 and is effectively shorted out by the timed switch when the timed switch is closed to energize the drive motor 18. Thus, during the normal drying cycle, the buzzer remains unenergized. However, upon completion of the drying cycle timed switch 24 opens so as to no longer short out the buzzer and thereby permit the buzzer to be energized in series with the motor run winding 20 through the centrifugal switch contact 25a closed with fixed contact 25c. This causes energization of the buzzer as the impedance of the buzzer is substantially higher than that of the run winding 20 so that only the buzzer will be effectively energized under this operating condition. The energization of the buzzer at this time continues until the coasting motor slows down to the preselected speed at which the centrifugal switch 25 is thrown back to the position where contact 25a is closed into contact 25b, thereby breaking the circuit to power supply lead L3 from the buzzer and discontinuing further production of the buzzer signal. In the conventional drier, such reduction in the motor speed occurs in approximately two to three seconds and, thus, the signal produced by the buzzer to indicate the termination of the normal drying cycle is a signal of approximately two to three seconds duration. When the cycle switch is set for anti-wrinkle operation with the moving contact 35a engageable with fixed contact 35c, a circuit is completed from the buzzer 15 through the centrifugal switch 25 to power supply lead L3 at all times during such closed condition of the switch 35. However, the pulser mechanism 36 permits such closed arrangement only at preselected intervals during the anti-wrinkle cycle, and thus the buzzer is energized intermittently during that cycle. In the illustrated embodiment, the pulser mechanism effects the engagement of moving contact 35a with fixed contact 35c at the end of approximately 81/2 minutes of operation of the drier in the anti-wrinkle mode and at the subsequent 5-minute intervals discussed above. Under this condition, the buzzer is connected in parallel with the series connection of the timed switch 24 and motor winding 20 and, thus, operation of the buzzer is controlled by the operation of the pulser mechanism 36. A highly desirable feature of the invention is the energization of the buzzer accurately at the termination of the normal drying cycle as such operation is effected without the need for control cams or the like controlling the buzzer, but rather, is controlled concurrently by the same timed switch that controls the operation of the drive motor. Thus, the operation of the buzzer is automatically accurately correlated with the termination of drive motor operation since the buzzer signal is initiated when timed switch 24 opens and terminated when centrifugal switch 25 operates from its run to its start condition. The same cycle switch is utilized in combination with the pulser mechanism to provide the additional desirable anti-wrinkle cycle indicating means and the use of the same single pole, double throw switch to effect each of these two different signal operations provides an improved low cost structure for this purpose. The normal drive motor timed control switch and the normal drive motor centrifugal switch are utilized in conjunction with the cycle switch in a novel manner to provide the highly desirable functioning described above by the alternative connection of the buzzer in series with the drive motor or in parallel therewith depending on the setting of the cycle switch. It should be understood that although the invention has been described in the context of a 240-volt electric drier, the invention could be utilized equally well with a gas drier or a 120-volt electric drier. The foregoing disclosure of specific embodiments is illustrative of the broad inventive concepts comprehended by the invention.
A control circuit for a drier wherein a buzzer is provided for signalling termination of the normal drying cycle or operation of the drier in an anti-wrinkle cycle. When utilized to signal the end of a normal cycle, the buzzer provides a short time duration signal and when utilized to indicate the operation of the drier in the anti-wrinkle cycle, the buzzer provides a longer duration signal at periodic intervals during the cycle. Control of the buzzer is by a single cycle switch connected in cooperation with a timed switch for controlling operation of the drier drive motor, and a centrifugal switch also provided for controlling operation of the drier drive motor. The cycle switch may be a double throw switch and may have an associated pulser mechanism for effecting the desired intermittent operation of the buzzer for indicating the anti-wrinkle cycle.
3
BACKGROUND OF THE INVENTION The present invention relates to a detection device, particularly for surface checking cigarettes. The surface quality of cigarettes coming off a production machine is normally checked by feeding the cigarettes successively through a detecting and monitoring device of the type described in U.S. Pat. No. 4,639,592. This comprises four separate optical units, each designed to detect surface flaws of various types on a respective quarter of the lateral surface of the cigarette, and each presenting a light source for directing a light beam on to the respective lateral surface quarter of the cigarette. The light rays reflected by each surface quarter are concentrated by the respective optical unit into a beam, which is sent to a respective monitoring unit normally comprising a telecamera. This produces an image, which is compared, inside the monitoring unit, with a specimen image, and, in the event any major discrepancies are detected between the two images, a signal is emitted for rejecting the cigarette. Though widely used and reliable enough from the operating standpoint, a major drawback of known detection devices of the aforementioned type is the relatively high cost, mainly due to featuring four monitoring units. Moreover, by virtue of each surface quarter of the cigarette requiring both a light source and an optical unit, known detection devices of the aforementioned type are also relatively cumbersome and, hence, difficult to accommodate, for example, on filter assembly machines. SUMMARY OF THE INVENTION It is an object of the present invention to provide a detection device designed to overcome the aforementioned drawbacks, and which, in particular, is relatively cheap to produce and compact as compared with the above known devices. A further object of the present invention is to provide a detection device designed to operate to a high degree of accuracy, and to supply the built-in detecting means with perfectly defined images. According to the present invention, there is provided a detection device, particularly for surface checking cigarettes, the device comprising at least one optical unit for detecting the surface characteristics of a respective half of the lateral surface of the cigarette; and light ray emitting means for illuminating said half of said surface; characterized by the fact that said optical unit comprises one monitoring unit; and means for deflecting the rays reflected by respective portions of said half of said surface, and which provide for deflecting all the rays reflected by said half of said surface into one reflected beam directed towards said one monitoring unit. According to a preferred embodiment of the present invention, said reflected ray deflecting means comprise two prismatic bodies facing respective surface quarters of the cigarette. BRIEF DESCRIPTION OF THE DRAWINGS A non-limiting embodiment of the present invention will be described by way of example with reference to the accompanying drawings, in which: FIG. 1 shows a partial side view of a preferred embodiment of the device according to the present invention; FIG. 2 shows a larger-scale detail of FIG. 1. DETAILED DESCRIPTION OF THE INVENTION Number 1 in FIG. 1 indicates a detection device for surface checking cigarettes 2 coming off a filter assembly machine (not shown). Device 1 comprises a pair of parallel, counter-rotating rollers 3 (only one of which is shown partially in FIG. 1). Rollers 3 each present a number of peripheral seats 4 for partially accommodating respective cigarettes 2, and are each rotated about a respective axis (not shown) so as to successively feed cigarettes 2 through two observation stations 5 (only one shown), at each of which a respective longitudinal half 6a of the lateral surface 6 of cigarettes 2 is observed. For each station 5, device 1 also comprises an optical unit 7 for observing and monitoring respective half 6a of surface 6. Each unit 7 presents an observation plane 8 containing the longitudinal axis 9 of cigarette 2 housed inside seat 4 in station 5, and which divides respective half 6a of surface 6 into two quarters 6b on either side of plane 8. Unit 7 comprises focusing means consisting of a known spherical optical system 10 acting as a lens; a known monitoring unit 11 connected in known manner to spherical optical system 10; and an anamorphic optical unit 12, which, together with spherical optical system 10, constitutes a device for concentrating rays on to unit 11, and is located on the opposite side of spherical optical system 10 to unit 11, for adapting the dimensions of the image of cigarette 2 to spherical optical system 10, or more specifically, for better exploiting the detecting surface of the photosensitive element. Unit 7 also comprises a pair of prismatic bodies 13 located on either side of plane 8 and facing respective quarters 6b of surface 6 of cigarette 2 in station 5. Bodies 13 each present a longitudinal axis (not shown) parallel to axis 9, and a pentagonal cross section; diverge from anamorphic optical unit 12 towards seat 4; and are defined, on the side facing seat 4, by respective flat active surfaces 14 defining a dihedron with its edge lying in plane 8, and each forming the same angle B with plane 8. On the opposite side to surface 14, each body 13 is defined laterally by two flat surfaces 15 and 16 parallel to axis 9, sloping in relation to respective surface 14, converging outwards, and connected to respective surface 14 by two flat surfaces 17 and 18 also parallel to axis 9, and of which surface 18 lies substantially in plane 8 and is tangent to surface 18 of the other body 13. Unit 7 also comprises a light source 19 for emitting a light beam 19a, which presents an axis 20 perpendicular to plane 8, and is so oriented as to impinge on a reflecting body 21 located between spherical optical system 10 and monitoring unit 11, for deflecting beam 19a (only half of which is shown in FIG. 2) in a direction parallel to plane 8, so that the rays 22 of beam 19a impinge on surface 16 of both bodies 13. In actual use, as they travel through bodies 13, rays 22 of beam 19a are deflected and divided into two beams 23 (only one shown in FIG. 2), the rays 24 of each of which form a variable angle of other than zero with plane 8, so as to provide for optimum illumination of a respective quarter 6b of surface 6 under observation. The incident rays 24 of each beam 23 are then reflected by respective quarter 6b of surface 6 to form reflected rays 24a, each of which impinges on respective surface 14 with an angle of incidence within the cone of refraction. Rays 24a thus travel through respective surface 14, and, deflected simply by a given angle of refraction, impinge on respective surface 15, which is so oriented that rays 24a form, with a perpendicular to surface 15, an angle greater than the half angle of the refraction cone. As a result, rays 24a are reflected totally by respective surface 15 on to respective surface 14, which, like surface 15, reflects them totally on to respective surface 16 in a direction substantially parallel to plane 8. Since, as shown in FIG. 2, surface 16 forms an angle very close to 90° with plane 8, rays 24a are simply deflected by surface 16 by a given angle of refraction, and continue in a direction substantially parallel to plane 8 and perpendicular to axis 9. More specifically, rays 24a from both bodies 13 converge into one beam 19b (only half of which is shown in FIG. 2), which reaches monitoring unit 11 via anamorphic optical unit 12 and spherical optical system 10. As it travels through anamorphic optical unit 12, beam 19b is compressed in a direction parallel to axis 9, and expanded in a direction perpendicular to plane 8, so as to present a section better suited to unit 11 on leaving unit 12. Unit 11 comprises, in known manner, a telecamera (not shown) or an array of photosensors, which, by means of beam 19b, is supplied with a composite image of the two quarters 6b of surface 6; and a known comparing device (not shown) in which the composite image is compared with a specimen image for detecting any discrepancies between the two. In the event discrepancies above a given threshold are detected, a signal is emitted in known manner for rejecting cigarette 2. According to a first variation, source 19 may be replaced by two light sources 25 (25') as indicated by the dot-and-dash lines, and which, unlike source 19, illuminate respective quarters 6b of surface 6 directly (or via bodies 13) by emitting respective beams 26 (26') . Bodies 13, which are relatively straightforward and cheap to produce, therefore provide, not only for halving the number of monitoring units required and so drastically reducing production cost, but also for achieving a relatively compact device particularly suitable for use on a filter assembly machine.
Cigarettes on a conveyor are surface checked, in at least one observation station, by means of at least one optical unit having a light source for directing light rays on to one half of the outer surface of the cigarette, and a pair of prismatic bodies facing respective quarters of the surface of the cigarette, and which provide for directing all the rays reflected from the aforementioned half of the surface into one beam directed towards one monitoring unit.
0
REFERENCE TO RELATED APPLICATIONS [0001] This application claims one or more inventions which were disclosed in Provisional Application No. 62/099,741, filed Jan. 5, 2015, entitled “Waste Collector with Dispenser”. The benefit under 35 USC §119(e) of the United States provisional application is hereby claimed, and the aforementioned application is hereby incorporated herein by reference. BACKGROUND OF THE INVENTION [0002] 1. Field of the Invention [0003] This invention relates to canisters and dispensers for pet waste disposable bags on rolls. It also relates to canisters and dispensers for small pet treats. More particularly, it pertains to an improvement to a single container that can store and dispense either bag rolls or pet treats. [0004] 2. Description of Related Art [0005] Dispensers for bags and treats add convenience when exercising a dog. This eliminates the hassle every time of having to fumble around looking for bags or forgetting to take one when taking out Rover. Also, it would be nice to have the option to have treats with you to reward Rover for his good behavior. Further, if a pooper scooper is taken along, it would be an advantage and convenient to have the device as an integral part of it. As such, it may be appreciated that there is a continuous need for a new and improved fixed dispenser that addresses some of the disadvantages of tearing off bags from a roll and could also be used for dispensing pellets. [0006] The most common device for carrying and dispensing pet waste bags and treats when exercising a dog is a simple canister. Roll bags are very common today. Typically fifteen bags of various colors and textures are link together with perforations and rolled onto a core. The canisters come in different shapes and sizes and can be carried on a leash or other convenient device. There are a few problems that can occur when dispensing bags from these canisters. First, threading the initial bag can sometimes be challenging because of the closed ended slots or openings for bag dispensing from the canister. Second, tearing a subsequent bag from the roll can also be a challenge and is more difficult with a stronger weighted bag. Properly tearing a bag off at the perforation is essential in order to keep next bag from pulling out of the canister prematurely. In most cases a bag requires two hands to tear it from the roll. This requires the bag to be pulled out of the dispenser beyond the perforation which leads to the next bag on the roll to hang out from the canister. Third, if bags need to be rewrapped onto the spool, this could also be a little cumbersome to do and many times the roll must be removed and rethreaded again. At times the canister caps fail and roll bags or treats fall out during a walk. Also the hanging clips can fail and the canisters can fall and get lost. [0007] U.S. Pat. No. 4,936,452 to Pauley describes an invention for dispensing of tissue where the tearing of the tissue at the perforation is not a requirement. This device a closed ended slot that when threading a new roll could be a little tricky. Finally, the anterior cylinder is non-rotational. [0008] PCT International Application publication WO2014/031940 to Williams describes a bag dispensing system with an outside plastic tube for the purpose of keeping the bags from sticking out. The anterior tube can rotate 360 degrees and has a disadvantage of jamming If a new bag gets pulled out too far after a bag was just torn off, the new bag hanging out could get wrapped around the inside dispenser by rotating the outside plastic tube too far. Bags would need to be removed and rethreaded to ready the device for use. [0009] U.S. Pat. No. 5,135,134 to Dancy provides a dispenser with one closed end slot with an anterior sleeve. Dispensing a bag is done be squeezing the outside of the device to keep the roll still, when a bag is dispensed. SUMMARY OF THE INVENTION [0010] A dual purpose vessel comprising a dispenser with a cover sleeve assembly mounted to a base. The base is fixed onto the end of a handle. Bags or pellets are stored inside the dispenser and dispensed through serrated slots or ports in the dispenser and the cover sleeve. BRIEF DESCRIPTION OF THE DRAWING [0011] FIG. 1 shows an isometric view of Container/Dispenser System dispensing a bag [0012] FIG. 2 shows an isometric view of Container/Dispenser System dispensing pellets [0013] FIG. 3 shows a front view of the invention [0014] FIG. 4 shows a cross sectional view of the invention [0015] FIG. 5 shows a side view of the Cover Sleeve and Dispenser [0016] FIG. 6 a shows a front view of the Cover Sleeve and Dispenser in Home position [0017] FIG. 6 b shows a front cross sectional view of the Cover Sleeve [0018] FIG. 7 shows the front view of the Container/Dispenser system in home position DETAILED DESCRIPTION OF THE INVENTION [0019] The Container/Dispenser System ( 100 ) is comprised of a Base ( 140 ) attached to a Dispenser ( 130 ) and a Cover Sleeve ( 110 ). The cover sleeve ( 110 ) is held into position on the dispenser ( 130 ) with cover sleeve interior upper groove ( 113 ) holding dispenser exterior upper track ( 133 ). Also, there is a cover sleeve interior lower track ( 114 ) fitting in a dispenser exterior lower groove ( 134 ). [0020] The cover sleeve will rotate 45 degrees from home position FIG. 7 . with the help of the dispenser exterior round key slot key ( 136 ) and the cover sleeve interior lower round stop tab ( 115 ). The dispenser exterior bushing ( 135 ) prevents the cover from rotating beyond the key points. [0021] This system is fixed to a pet waste collector such as the GoGo Stik® Waste Collector from AB Innovations of Syracuse, N.Y., at the end of the handle ( 150 ). The top of the cover sleeve has a loop hanger ( 119 ) that allows the cover sleeve to be removed, replaced or rotated. It also provides the pet scooper with the ability to hang up on a wall hook. [0022] This invention deals with a dispensing canister that will dispense standard roll bags and address these problems. As mentioned, another advantage of this canister is that it can dispense treats or pellets. [0023] This invention provides for a device that can double for either a bag roll dispenser or a treat dispenser. The bag dispenser has improvements over the simple canister, closed ended dispensing slots. A serrated open end slot configuration on the dispenser and serrated open end slot on the cover sleeve assist in tearing a bag off and keeping the remaining bags secure. Threading of bags is simpler and easier. [0024] A roll of bags ( 121 ) is placed in the cylindrical dispenser ( 130 ) onto the center spindle ( 122 ) while threading the first bag edge ( 120 ) into the top of the open slot ( 132 ) in the wall of the dispenser ( 130 ). Once in position, the cylindrical cover sleeve ( 110 ) is placed into position over the dispenser ( 130 ) while guiding the threaded bag up and through the bottom end of the cover sleeve open slot ( 112 ) in the wall of the cover sleeve ( 110 ). Both the dispenser and cover sleeve slots line up and be in the home position FIG. 7 , when done. The roll freely rotates in the canister and torn off at the perforation when bags are dispensed. [0025] Tearing off a bag for use is done by pulling the bag out of the slots ( 132 ), ( 112 ) until the perforation before the next bag is seen. The cover sleeve ( 110 ) can be rotated 45 degrees clockwise or 45 degrees counter clockwise FIG. 1 and FIG. 4 . from home position The cover sleeve will snap into one of these positions through the use of the cover sleeve round slot key ( 115 ) and the dispenser matching round slot ( 136 ) from home position. [0026] When in position, a bag can be torn from the device utilizing both serrated slot edges from the cover sleeve ( 110 ) and dispenser ( 130 ). The narrow dispenser serrated slot also helps in stabilizing the bag from moving while the narrow serrated cover sleeve slot helps in the tearing of the bag off of the roll at the perforation. [0027] As a treat dispenser FIG. 2 ., the dispenser is held at up at an angle that assists in the filling of the dispenser with pellets ( 160 ). The dispenser port is facing up such that a finger can block the port when filling. Once filled, the cover sleeve ( 110 ) is placed onto the dispenser ( 130 ) in the home position ( FIG. 7 ) where both concentric slots and ports line up. The pellet dispensing position is at the home position. Both the dispenser port ( 131 ) and the cover sleeve port ( 111 ) are open to allow treats to dispense from the canister FIG. 2 . When done dispensing, the cover sleeve can be rotated either 45 degrees clockwise or 45 degrees counter clockwise to close off the ports. [0000] The Dispenser provides: 1. A serrated open ended slot that aids in threading roll bags; 2. A serrated slot that aids in tearing bags from a roll at the perforation in conjunction with the cover sleeve serrated slot; 3. A port for dispensing pellets when the device is used for pellets rather than bag. The cover sleeve provides multiple advantages: 1. The serrated open end slot allows for easy bag threading; 2. The serrated slot assists in the tear off of a bag at the bags' perforations and works with the dispenser serrated slot; 3. The inside tabs on either side of the port allow the cover to snap into place when rotated 45 degrees from home position either clockwise or counter clockwise. This helps to keep bags from wrapping around the inside dispenser and keeps the device from jamming The leading tab aligns and rests in the key slot on the dispenser. This keeps the cover sleeve in place while the lagging tab pinches the bag leader against the outer dispenser wall as it exits through the port; 4. The rotating cover closes off the dispenser port if the device is used in dispensing pellets. [0035] Accordingly, it is to be understood that the embodiments of the invention herein described are merely illustrative of the application of the principles of the invention. Reference herein to details of the illustrated embodiments is not intended to limit the scope of the claims, which themselves recite those features regarded as essential to the invention. [0000] List of Reference Numbers 100 Container/Dispenser System for treat dispensing system 110 Cover Sleeve 111 Cover Sleeve Port 112 Cover Sleeve Serrated Slot 113 Cover Sleeve interior upper groove 114 Cover Sleeve interior lower track 115 Cover Sleeve interior lower stop tab 119 Cover Sleeve Loop 120 Plastic Bag 121 Plastic Bag Roll 122 Roll Tapered Dowel 130 Dispenser 131 Dispenser Port 132 Dispenser Serrated Slot 133 Dispenser Exterior Upper Track 134 Dispenser Exterior Lower Groove 135 Dispenser Exterior Bushing/Track 136 Dispenser Exterior Round Slot/Key 140 Base 150 Handle 160 Pellets
A dual purpose vessel having a dispenser with a cover sleeve assembly mounted to a base. The base is fixed onto the end of a handle. Bags or treats are stored inside the dispenser and dispensed through serrated slots in the dispenser and the cover sleeve.
1
TECHNICAL FIELD This invention relates to the art of apparatus for obtaining a randomly selected sample from a group of objects. The invention finds particular utility in obtaining a sample of fruit. BACKGROUND ART In fruit harvesting, it is necessary to obtain a random sample of the harvested fruit. For example, in the harvesting of oranges, a random sample of a harvested crop is required for inspection by agricultural authorities and for inspection by the purchaser of the harvested crop. Random samples are obtained in many ways, and the most useful methods are those which cooperate with loading and bagging apparatus. In a known random sampling system, a horizontal surface over which the harvested crop must pass has holes therein for allowing some of the fruit to fall through the holes and be collected as a sample. This arrangement is not practical because it does not allow the selection of a random sample of a predetermined size and, furthermore requires the entire horizontal surface to be covered with objects in order to obtain a truly random sample. U.S. Pat. No. 3,672,224 (Starr) shows a sampling system where articles to be sampled are directed to a discharge chute to be sampled. U.S. Pat. No. 3,111,034 (Hostetler) shows a perforated apron at one end of a conveyor. The inspector may move holes in the apron to obtain a sample. U.S. Pat. No. 2,367,397 (Harlow) shows a sampling apparatus which employs a trapdoor through which a sample drops to a chute beneath the door. SUMMARY OF THE INVENTION In accordance with the invention, two sampling stations are employed in series to obtain a random sample of a predetermined size. A first sampling mechanism causes a relatively large sample to be obtained, and a second mechanism allows a random selection of a second sample of any desired size to be selected from the first sample. The first sampling mechanism comprises an apparatus for striking the bottom of a moving conveyor belt thus causing the fruit on the conveyor belt to be bounced upwardly away from the moving conveyor belt. Since the objects were initially moving in a horizontal direction, they maintain their horizontal direction and assume a parabolic trajectory. A receptacle intercepts the objects which have assumed this trajectory and the remainder of the objects are carried by the conveyor belt to a packing station. The striking means causes a relatively large sample of objects to be thrown into the receptacle. A second conveyor belt then carries objects from this receptacle to a second sampling station. The second conveyor belt is unique in that it provides a plurality of cleats, each of which engages a single one of the objects. This causes the objects in the first sample to move single-file into the second station. The second station preferably includes a photocell arrangement for detecting the presence of each one of the objects and for operating a diverter door in response to electronic signals representing the presence of an object and a signal representing the ultimate size of the desired sample. For example, if it is determined to obtain a second sample comprising one-fifth of the first random sample, it is only necessary to provide signals instructing the diverter to select one of every five objects in a random fashion. The apparatus of the invention has several advantages. There is no spillage of the objects, and nothing blocks the line of moving objects. The second conveyor carries fruit above the main conveyor to prevent the loss of elevation which accompanies some prior art samplers. Further, the inventive apparatus is compact and is easily installed on an existing conveyor. It is an object of this invention to provide a random sampling apparatus. It is another object of this invention to provide a random sampling apparatus having two sampling stations wherein the first sampling station provides a sample larger that that which is required in the second sampling station. It is a still further object of this invention to provide a sampling station wherein a sample is obtained by causing objects carried by a moving conveyor to assume a trajectory away from the conveyor to thereby be separated from objects remaining on the conveyor. It is yet another object of the invention to provide a tilted conveyor having cleats for providing a single-file flow of said objects. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side view of a sampling apparatus in accordance with the invention. FIG. 2 is an end view of the apparatus shown in FIG. 1. FIG. 3 is a top view of the apparatus shown in FIG. 1. FIG. 4 is a cross-section taken along line 4--4 of FIG. 1. FIG. 5 is an enlarged cross-section taken along line 5--5 of FIG. 1. FIG. 6 is a side view of an impact apparatus in accordance with the invention. FIG. 7 is a top view of the impact apparatus shown in FIG. 6. DETAILED DESCRIPTION OF THE INVENTION FIG. 1 shows a side view of a random sampling apparatus in accordance with the invention. A conveyor assembly 2, as known in the art, includes a flexible conveyor belt 4 and transports a plurality of objects 6 in a generally horizontal path. The belt is preferably continuous and a lower course 4' moves in a direction opposite to that of an upper course. The conveyor assembly 2 is supported by a frame structure 8, 10, and 26. The objects are preferably fruit. A first sampling station 12 is located along the path of objects 6 carried by the flexible conveyor belt 4. First sampling station 12 comprises an apparatus for striking a lower surface of the flexible conveyor belt 4 to cause a plurality of the objects 6 to assume a trajectory, such as that indicated by the dashed line 14. The preferred embodiment of the striking apparatus will be described in detail below, and at this point it is only necessary to recognise that it is located between upper and lower courses of the flexible conveyor belt 4 so that it has access to a lower surface of the upper course. When the striking means engages the lower surface of the conveyor belt, some of the objects 6 are thrown upwardly, and since the objects 6 had a horizontal velocity from right to left of FIG. 1, they assume a trajectory 14. The objects 6 which are not thrown upwardly by the impact of the striking means are carried along the conveyor assembly 2 for further processing. A receptacle 16 extends across belt 4 and gathers objects by intersecting the trajectory 14 to thus separate a first sample of objects 6. The first sample received in receptacle 16 is directed to a second conveyor 18 and carried one-by-one into a second sampling station 20. At the second sampling station 20, a predetermined number of the objects 6 are directed into a chute 22, and the remainder is returned to the flexible conveyor belt 4. Objects representing the final sample are directed into chute 22 and collected at discharge end 24. FIG. 2 is an end view of the apparatus of FIG. 1, except that supporting frame members 8 and 10 have been omitted and the frame member 26 is partially shown. The upper end of second conveyor 18 includes a drive motor 28 for driving a second conveyor belt 30. Cleats 32 are attached to a lower edge of the second conveyor belt 30 for a purpose which will be described in more detail below. At this point, it is sufficient to point out that the second conveyor belt 30 is tilted and that cleats 32 produce a single-file line of objects 6 from the first sampling station 12. A diverting plate 34 is shown in two positions in FIG. 2. In a first position, the plate allows objects to follow the path indicated by arrow 36 to thereby return them to the flexible conveyor belt 4. In the second position, indicated by the reference numeral 34', the diverting plate causes objects 6 to enter the chute 22 as indicated by the arrow 38. The operation of plate 34 will be more fully described below. FIG. 3 is a top view of the apparatus in accordance with the invention. This figure shows the trajectory 14 which causes fruit to be received in a receptacle 16 and carried by a tilted tray 17 into a lower end of the second conveyor 18. Cleats 32 are of such a size and shape that only a single object 6 is engaged by each cleat. At the upper, or discharge, end 20 of second conveyor 18 is a detection apparatus for determining the presence of an object 6 at the discharge end. In the preferred embodiment, the detection apparatus includes a light source and photodetector 40 which directs a narrow beam of light 42 across the upper end of the second conveyor and receives light from retroreflector 44. The presence of an object 6 is detected by a change in the voltage level produced by the photodetector as a result of an object 6 blocking the beam 42. It will be appreciated that many kinds of detection apparatus may be employed to accomplish the same purpose. FIG. 4 is a cross-section taken along line 4--4 of FIG. 1 and shows the receptacle 16 and tray 17 which receive objects 6 from the first sampling station 12. FIG. 5 is an enlarged cross-section taken along line 5--5 of FIG. 1. This figure shows in some detail the preferred construction of the second conveyor 18. A second conveyor belt 30 is made of flexible material and is a continuous belt. Belt 30 is driven by a drive cylinder 46 which is secured to a shaft 48. The shaft is supported at opposite ends of a housing 50 by bearings 52. Drive cylinder 46 preferably is covered with a friction material 54 to assist in transferring force from the cylinder 46 to the second conveyor belt 30. In addition, a V-shaped protrusion 56 engages a pulley 58 which is also secured to the shaft 48 for driving the second conveyor belt 30. Shaft 48 is operatively connected to drive motor 28 by a gearbox 60. Second conveyor belt 30 has cleats 32 along a lower edge thereof for engaging individual objects 6. The cleats are preferably thin, tapered elements and a broader portion engages a single object 6 while a tapered portion prevents more than one object from being engaged. Second conveyor belt 30 is tilted about a horizontal axis in two directions. First, it is tilted in a longitudinal direction as shown in FIG. 1 and secondly, it is tilted in a lateral direction as shown in FIG. 5. The longitudinal tilt is preferably about 20 degrees and the lateral tilt is preferably about 25 degrees, each with respect to a horizontal direction. While the second conveyor is shown in the figures carrying objects in the same direction as those of conveyor 4, it will be appreciated that it could carry the objects in an opposite direction. FIGS. 6 and 7 are enlarged views of the preferred striking means used in the first sampling station 12 for causing objects 6 to assume the trajectory 14. Two bell cranks 62 (one of which shows in FIG. 6) are mounted to a common shaft 64. The shaft is carried by bearings 66. A hydraulic actuator 68 has an actuating shaft 70 which is connected to an end 72 of the bell crank 62 by clevis 74. The hydraulic actuator 68 is energized to control the actuating shaft 70 thus causing bell crank 62 to pivot about the pivotal connection provided by the bearings 66. A second end 76 of the bell crank 62 is adapted to engage the lower surface of flexible conveyor belt 4 when in the position shown in solid lines in FIG. 6. Rollers 78, 80 are connected between bell cranks 62 to provide a reduced-friction contact with the conveyor belt 4. The bell cranks 62 are preferably aligned with the direction of movement of the conveyor belt 4, as shown in FIG. 1, so that engagement with the belt does no damage but only causes the roller 78, 80 to rotate. A first bumper 82 is located on actuator 68 to absorb shock created when bell cranks 62 assume the position shown in solid lines in FIG. 6 wherein the bell cranks 62 are striking the conveyor belt 4. A second bumper 84 is located on a housing 86 and engages the end 72 of the bell cranks 62 when in the position shown in dashed lines. FIG. 7 is a top view of the striking apparatus shown in FIG. 6. A large tubular member 88 connects bell cranks 62 to insure their operation together. In the preferred embodiment, the actuators 68 are air-operated and air is supplied to a connector 90 by a hose 92. Separate supply pipes 94, 96 carry fluid from the connector 90 to respective actuators 68. Of course, the actuators may be of any form, for example, they may be electrically operated solenoids. In operation, fruit, for example, oranges, is loaded onto the flexible conveyor belt 4 and thereby carried into the first sampling station 12. The bell crank striking apparatus is programmed to apply an impulse to the lower side of conveyor belt 4 at random or predetermined intervals to cause a first sample of fruit to be thrown upwardly into the receptacle 16. The first sample of fruit flows into the lower end of second conveyor 18 which then carries single pieces of fruit upwardly to the second sampling station 20. The cooperation of the tilted conveyor belt 30 and the cleats 32 causes only individual pieces of fruit to be carried to station 20. Detecting means determines the presence of a piece of fruit and supplies information to a circuit of conventional design which also receives information regarding the size of the sample desired to be taken. Output signals from the circuit control the operation of diverter plate 34 and either causes fruit to be deflected into chute 22 or allowed to return to the conveyor 4. Fruit which has been deflected to chute 22 is then collected at the output end 24 for inspection. It will be appreciated that the apparatus in accordance with the invention efficiently samples objects by first taking a large random sample and then obtaining a second random sample from the first. Modifications of the apparatus within the scope of the appended claims will be apparent to those of skill in the art.
Apparatus for obtaining a sample of objects is provided. The objects are carried by a first conveyor belt and are sampled by striking a lower surface of the conveyor belt to cause some of the objects to be thrown upwardly over a barrier into a receptacle. The objects from the receptacle are carried by a second conveyor which has cleats for carrying objects to a detector one-by-one. The detector operates a deflecting plate to obtain a second sample for inspection. Objects which are not deflected by the plate are returned to the first conveyor belt, while those which are deflected enter a chute for collection. The apparatus for delivering an impact to the conveyor belt preferably comprises a bell crank which strikes the conveyor belt 4 in response to a hydraulic actuator.
6
FIELD OF THE INVENTION This invention relates to vapor-liquid contacting apparatus and specific features that improve the efficiency and capacity of this operation. The invention therefore relates to, for example, apparatus used as fractionation trays within fractional distillation columns. The invention may also be used in a variety of other gas-liquid contacting operations such as acid gas scrubbing or absorption processes. BACKGROUND OF THE INVENTION Fractional distillation columns having a number of vertically spaced distillation trays are widely employed in the hydrocarbon processing, chemical, and petrochemical industries. Accordingly, a large amount of research, development, and creative thinking has been devoted to providing improved fractional distillation trays. Fractionation tray development has therefore provided many variations in contacting area structure, downcomer design, and overall tray structure. Vapor-liquid contacting devices are used in a wide variety of applications for separating liquid or vapor mixtures. One of the major applications of the vapor-liquid contacting devices is in the separation of chemical compounds via fractional distillation. These devices are also used to contact a gas stream with a treating liquid which selectively removes a product compound or an impurity from the gas stream. Within a column containing vapor-liquid contacting devices, liquid flows in a generally downward direction and vapor rises vertically through the column. On each vapor-liquid contacting device, liquid flows in a generally horizontal direction across the device and vapor flows up through perforations on the device. The cross flow of vapor and liquid streams on each device generates a froth for intimate vapor-liquid contacting and mass transfer. The apparatus can be used in the separation of essentially any chemical compound amenable to separation or purification by fractional distillation. Fractionation trays are widely used in the separation of specific hydrocarbons such as propane and propylene or benzene and toluene or in the separation of various hydrocarbon fractions such as LPG (liquefied petroleum gas), naphtha or kerosene. The chemical compounds separated with the subject apparatus are not limited to hydrocarbons but may include any compound having sufficient volatility and temperature stability to be separated by fractional distillation. Examples of these materials are acetic acid, water, acetone, acetylene, styrene acrylonitrile, butadiene, cresol, xylene, chlorobenzenes, ethylene, ethane, propane, propylene, xylenols, vinyl acetate, phenol, iso and normal butane, butylenes, pentanes, heptanes, hexanes, halogenated hydrocarbons, aldehydes, ethers such as MTBE and TAME, and alcohols including tertiary butyl alcohol and isopropyl alcohol. One important issue in the field of vapor-liquid contacting columns is improving the capacity of the trays to allow vapor and liquid to flow from tray to tray without flooding. A second important issue in the field is improving the efficiency of the trays for mass transfer between vapor and liquid. In a well-known classic study by W. K. Lewis in 1936, it was found that the mass transfer efficiency of vapor-liquid contacting trays could be maximized by bringing an unmixed vapor into contact with liquid flows across each successive tray in the same direction (Case 2). The Case 2 is referred to as a parallel flow, which, as used herein, refers to liquid flows on vertical adjacent or successive trays rather than to liquid flows on a single tray. Lewis' Case 2 ensures that the driving force for mass transfer on a given tray is nearly the same regardless of where that mass transfer occurs on the tray. Because of this, substantial increases in efficiency can be obtained when using a tray operated according to Lewis' Case 2. U.S. Pat. No. 5,223,183 to Monkelbaan, et al. teaches a parallel flow tray with at least one central downcomer and no side downcomers. The downcomers of each tray are aligned with the downcomers on the other trays of the column such that the downcomers on one tray are immediately below those on the tray above. The outlets of one downcomer are directly above the inlet of another. A pair of inclined liquid deflecting baffles over each downcomer connects the outlets and inlets of vertically adjacent downcomers and provides a crisscrossing liquid flow path. The downcomer baffles prevent liquid from the tray above from entering each downcomer and define the direction of liquid flow onto the tray deck. The inclined surface of the baffle also imparts a horizontal momentum to the descending liquid which tends to push the liquid and froth present on the tray towards the inlet of the outlet downcomer for this portion or zone of the tray. In certain designs of the trays there is provided a perforated anti-penetration weir on the lower end of the downcomer baffles, with the weir being perpendicular to the downcomer baffle. Further, froth flow into an outlet downcomer is pinched by the downcomer right above, which may reduce tray capacity. U.S. Pat. No. 5,318,732 to Monkelbaan, et al. teaches another parallel flow multiple downcomer type fractionation tray, which increases tray capacity by providing imperforate stilling decks that extend across the tray deck surface outward from the downcomer inlet opening together with vertical inlet weirs attached to the outer end of the stilling decks. The inlet weirs may function as pre-weirs used in addition to the conventional inlet weir formed by the upward extension of the downcomer side wall. Further, the stilling decks help reduce pinching; however they also reduce the active area of the deck. Therefore an improved high-capacity tray providing a Lewis Case 2 parallel flow pattern is needed in the art. SUMMARY OF THE INVENTION Two determinants of the quality of a contacting tray are its efficiency for performing a process and its capacity in terms of liquid or vapor traffic. It is an objective of the subject invention to increase the efficiency of contacting trays with Lewis Case 2 vapor-liquid contacting arrangement. It is another objective of the invention to provide a vapor-liquid contacting apparatus with improved capacity. The invention comprises multiple configurations of a parallel flow multiple downcomer tray for vapor-liquid contacting processes such as the separation of chemical compounds via fractional distillation or the removal of a component of a gas stream with a treating liquid. In one embodiment, side downcomers are incorporated into a parallel flow multiple downcomer tray having a center baffle. In another embodiment, the downcomers have an inclined side wall that directs liquid onto the deck below the downcomer. The inclined side wall also provides additional volume above the inferior downcomer inlet to reduce pinching at this inlet without the need for a stilling deck. In a further embodiment, features of the first two embodiments are combined. More particularly, the invention comprises, in one form thereof, a vapor-liquid contacting tray that includes at least one centrally located downcomer. The vapor-liquid contacting tray further includes a means to define vertical liquid flow paths for liquid flowing through each central downcomer onto a subsequent tray that comprises an inclined downcomer baffle. A plurality of vapor-liquid contacting decks is included on the tray. Two side downcomers are included proximate to the outer perimeter of the tray. Each side downcomer has a liquid receiving portion and a liquid distributing portion wherein the receiving portion directs liquid to the distributing portion and the distributing portion is substantially sealed against fluid entering directly from a proximate contacting deck. A central baffle extends between at least two of the downcomers and intersects at least one of the contacting decks. In another embodiment, the invention comprises a vapor-liquid contacting tray that has a generally circular circumference and includes a plurality of central downcomers that are formed by a first elongate side wall and an opposing second elongate side wall extending a shorter vertical distance below a proximate contacting deck than the first elongate side wall. Each downcomer further includes a bottom plate that intersects the first elongate side wall. The vapor-liquid contacting tray further includes a means to define vertical liquid flow paths for liquid flowing through each downcomer onto a subsequent tray comprising an inclined downcomer baffle, wherein the downcomer baffle extends from the second elongate side wall, intersects the bottom plate, and extends at least to a vertical plane formed by the first elongate side wall. A plurality of vapor-liquid contacting decks is included on the tray. A central baffle extends between at least two of the plurality of downcomers and intersects at least one of the contacting decks. A further form of the invention comprises a vapor-liquid contacting tray that includes at least one centrally located downcomer, a means to define vertical liquid flow paths for liquid flowing through each central downcomer onto a subsequent tray comprising an inclined downcomer baffle, and a plurality of vapor-liquid contacting decks. A bubble promoter, which comprises a perforated plate, is situated on the tray to direct liquid from the inclined downcomer baffle to one of the contacting decks. A central baffle extends between at least two of the downcomers and intersects at least one of the contacting decks. An even further form of the invention comprises a vapor-liquid contacting tray that includes a plurality of vapor-liquid contacting decks and two side downcomers proximate to the outer perimeter of the tray. Each side downcomer has a liquid receiving portion and a liquid distributing portion wherein the receiving portion directs liquid to the distributing portion. A cover is included over the liquid distributing portion that prevents liquid from a superior side downcomer from entering the liquid distributing portion. The cover also directs vapor in the liquid distributing portion to a vapor flow path outside the perimeter of the tray. A still further form of the invention comprises a vapor-liquid contacting tray that has a generally circular circumference and includes at least one centrally located downcomer, a plurality of vapor-liquid contacting decks, and two side downcomers proximate to the outer perimeter of said tray. Each side downcomer has a liquid receiving portion and a liquid distributing portion wherein the receiving portion directs liquid to the distributing portion. A central baffle extends between at least two of the downcomers and intersects at least one of the contacting decks. The central baffle comprises a bend proximate to each of the side downcomers, which increases the size of the liquid receiving portions. The invention further comprises a central downcomer for a vapor-liquid contacting tray, having a first portion and a second portion, which is substantially a mirror image of the first portion. Each of the first and second portions include a first elongate side wall, an opposing second elongate side wall extending a shorter vertical distance below the proximate contacting deck than the first elongate side wall, a bottom plate that intersects the first elongate side wall, an inclined downcomer baffle that extends from the second elongate side wall, and an extension flange. The first and second portions fit together such that each of the extension flanges overlaps with the complimentary inclined downcomer baffle and second elongate side wall. In a particular embodiment, each of the first and second portions is made from a single sheet of material. The central downcomer may further include cross braces between the first and second elongate side walls of each portion. BRIEF DESCRIPTION OF THE DRAWINGS The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become apparent and be better understood by reference to the following description of several embodiments of the invention in conjunction with the accompanying drawings, wherein: FIG. 1 is a schematic view of a vapor-liquid contacting column having a plurality of vapor-liquid contacting trays according to the present invention; FIG. 2 is a schematic plan view of the first embodiment of the parallel flow multiple downcomer fractionation tray of the present invention; FIG. 3 is a schematic cross-sectional view of a column of trays according to FIG. 2 ; FIGS. 4A and 4B are schematics of a floating valve; FIG. 5 is a schematic plan view of the tray of FIG. 2 having a swept-back side weir and a bent center baffle; FIG. 6 is a schematic plan view of the second embodiment of the parallel flow multiple downcomer fractionation tray of the present invention; FIG. 7 is a schematic cross-sectional view of a column of trays according to FIG. 6 ; FIG. 8A is a bottom isometric view of a strengthened central downcomer; FIG. 8B is a top isometric view of the strengthened central downcomer of FIG. 8A ; FIGS. 9A–14 are various schematic views of the third embodiment of the parallel flow multiple downcomer fractionation tray of the present invention; and FIGS. 15 and 16 are schematic cross-sectional views of further embodiments of the parallel flow multiple downcomer fractionation tray of the present invention. Corresponding reference characters indicate corresponding parts throughout the several views. The examples set out herein illustrate several embodiments of the invention but should not be construed as limiting the scope of the invention in any manner. DETAILED DESCRIPTION Referring to FIG. 1 , there is shown an example of a vapor-liquid contacting column having a plurality of vapor-liquid contacting trays of the present invention. The details of the trays will be disclosed in the subsequent embodiments of the invention. The column 10 includes a cylindrical inner chamber 11 , a top section 12 , a bottom section 14 , and a plurality of vapor-liquid contacting trays 16 having a circular perimeter. The top section 12 collects vapor from the chamber 11 and supplies liquid to the chamber 11 . In certain applications, such as continuous fractionation, the top section 12 is in fluid communication with a condenser that condenses the vapor and adds a portion of the resultant liquid to the liquid supply to the chamber 11 . The bottom section 14 collects liquid from the chamber 11 and supplies vapor to the chamber 11 . Similar to the top section 12 , in certain applications, such as continuous fractionation, the bottom section 14 is in fluid communication with a reboiler that converts a portion of the liquid to vapor, which is added to the vapor supply. The column 10 may also include one or more intermediate feeds that adds a liquid or vapor mixture to the middle of the column 10 with some trays 16 above the feed and some trays 16 below the feed. Each tray 16 comprises a contacting deck 18 , at least one downcomer 20 , and at least one inclined downcomer baffle 22 . A particular embodiment of the invention shown in FIGS. 2 and 3 includes a plurality of parallel flow multiple downcomer fractionation trays 100 having at least one central downcomer 102 and two side downcomers 104 . Between each two downcomers 102 and 104 , each tray 100 includes active areas in the form of a perforated deck 106 . The deck 106 is bisected by central baffle 108 . The central downcomer 102 includes side walls 110 , a bottom plate 112 , stilling decks 114 , and inlet weirs 116 . The flat, horizontal bottom plate 112 extends between the side walls 110 . A number of openings 118 are provided in the bottom plate for the exit of the liquid which accumulates within the central downcomer 102 . The purpose of the bottom plate 112 is to retard the liquid flow sufficiently that the bottom of the central downcomer 102 is dynamically sealed by liquid to the upward passage of vapor. The openings may be circular, square or elongated in either direction, that is, along the width or length of the central downcomer 102 . The sealing of the downcomer outlet to upward vapor flow could be accomplished by other structures as well. The stilling decks 114 are imperforate, and thus inactive, regions just prior to the inlets of each central downcomer 102 . The combination of the inlet weir 116 and the stilling deck 114 helps prevent pinching by providing an area near the inlet of the central downcomer 102 that doesn't add vapor to the froth. The central downcomers 102 may be supported by any conventional means such as a support ring, not shown, which is welded to the inner surface of the column wall. The deck 106 may be supported, for example, by an angle-iron support welded to the side walls 110 and the support ring welded to the column wall. The central downcomers 102 and the deck 106 are bolted, clamped, or otherwise affixed to the supports so that the central downcomers 102 and the deck 106 are kept in position during operation. The central downcomers 102 may act as the main supports for the tray 100 ; however, additional support beams may need to be included for substantially large trays. Further, strengthened central downcomers may be used. An inclined baffle 120 is situated between the bottom of a central downcomer 102 and the top of a central downcomer 102 immediately below it. It may be seen that the inclined baffles 120 extend between the central downcomers 102 in such a manner that liquid may not travel horizontally over the central downcomer 102 from one decking surface 106 to another. Liquid descending from one central downcomer 102 is prevented from falling into the next lower central downcomer 102 and must flow horizontally across the decking 106 to a different downcomer, whether it's a side downcomer 104 as shown in FIG. 3 , or another central downcomer 102 in order to proceed to the subsequent tray. In this embodiment two inclined baffles 120 cover the inlet of each central downcomer 102 . The inclined baffles 120 have opposite slopes that deliver liquid onto deck portions 106 on different sides of the central downcomer 102 such that the liquid flows in the direction of the arrows. In this embodiment the inclined baffles 120 on one side of the tray 100 all slope in the same direction, and the inclined baffles 120 on the other side (or other half) of the column face in the opposite direction. Liquid therefore flows in the opposite direction on the two sides of any one tray 100 , but flows in the same direction (parallel flow) on all deck areas 106 on one side of each tray 100 . A perforated anti-penetration or distribution weir 122 may be situated at the bottom of each of the inclined baffles 120 . In the present embodiment, the distribution weir 122 is inclined for 0 to 90 degrees, preferably about 45 degrees, to horizontal. The side downcomers 104 are provided to improve the fluid handling at the sides of the tray 100 . Each of the downcomers 104 includes a receiving portion 124 and a distribution portion 126 . The receiving portion 124 includes a side weir 128 and an imperforate, sloped bottom plate 130 , which is oriented to direct liquid towards the distribution portion 126 . The distribution portion 126 includes a bottom plate 112 as described above with the central downcomers 102 . An inclined baffle 120 and distribution weir 122 are situated below the distribution portion 126 . The deck 106 is perforated to allow vapor to flow through the deck 106 and contact the fluid on the deck 106 . The perforations may take many forms including evenly spaced, circular holes and a number of vapor-directing slots. The slots are oriented such that the vapor rising upward through the deck 106 through these slots imparts a horizontal thrust or momentum to the liquid or froth on the tray 100 in the direction of the nearest outlet downcomer. There is therefore achieved a more rapid passage of the froth into the downcomer means and a decrease in the froth height on the tray. More importantly by proper slot arrangement liquid flows uniformly across deck 106 into downcomer means. These slots and their function may resemble those described in U.S. Pat. No. 4,499,035, which is incorporated herein by reference. U.S. Pat. No. 3,417,975 issued to B. Williams et al. provides representations of a portion of decking material having both circular perforations and flow directing slots. This patent is also incorporated herein for its teaching as to the design and usage of flow directing slots. FIG. 4A is an enlarged schematic view of an alternate flow opening within the deck 106 . Deck 106 has valve 130 in opening 132 . FIG. 4B is an alternative flow opening with a venturi type opening 132 ′ created by extrusion or pressing of the deck 106 . Valve 130 is inserted into venturi opening 132 ′ of deck 106 . At the midpoint of each downcomer, a central baffle 108 rises upward from each deck area 106 of the overall tray surface. This central baffle 108 may be formed from a number of connecting plates or a single plate. The central baffle 108 prevents liquid and froth present on the two sides of the central baffle 108 from admixing. The central baffle 108 terminates a short distance below the next higher tray to provide a gap which allows pressure and vapor flow equalization. The central baffle 108 optionally includes equalization ports in the middle of the deck, remote from the downcomers as described in a subsequent embodiment with reference to FIGS. 9A and 9B . As one can see with reference to FIGS. 2 and 3 , the side weirs 128 are significantly shorter than the inlet weirs 116 associated with the inlets to the central downcomers 102 . This may limit the capacity of the tray 100 because of more liquid accumulation on the deck 106 proximate to the inlet of a side downcomer 104 than proximate to the inlet of a central downcomer 102 . A swept-back side weir 128 ′, a swept back central baffle 108 ′, or both, as shown in FIG. 5 , cooperate with a side downcomer that is unequally divided between a receiving portion and a distributing portion to increase the length of the side weir thereby reducing the difference in weir loads between the side downcomers 104 and the central downcomers 102 . Also importantly, the use of swept-back weir 128 ′ and the swept-back central baffle 108 ′ increases the entrance space of the side downcomer 104 , and therefore, reduces downcomer choking tendency. Thus the capacity of the side downcomer 104 is increased so that it is substantially equal to the capacity of the central downcomers 102 . As shown in FIG. 3 the column wall may serve as a side wall of the side downcomers. In other embodiments two side walls may define the distribution portion and/or receiving portion with one of the side walls conforming to shape of the column in an abutting or spaced-apart relationship therewith. A second embodiment of the invention, shown in FIGS. 6 and 7 , includes a tray 200 having at least one central downcomer 202 . Each central downcomer 202 includes a side wall 210 a , a shortened side wall 210 b , a bottom plate 212 , an inlet weir 216 defined by the portion of side wall 210 b above the deck 206 , a liquid balancing box 234 , and an inclined baffle 220 with an anti-penetration weir 222 . The bottom plate 212 includes openings 218 for the exit of the liquid which accumulates within the central downcomer 202 . In this embodiment, the inclined baffle 220 is incorporated into one side wall 210 b to form a sloped downcomer that provides additional volume above the inlet to the central downcomer 202 . The extension of the shortened side wall 210 b below the decking can improve tray strength and aid in supporting the decking. However, extension of the shortened side wall 210 b below the decking is not required. Thus, if the first side wall extends below the decking and the second side wall does not extend below the decking, the requirement in this embodiment that the second elongate side wall extends a shorter distance below the decking than the first elongate side wall is still satisfied. The additional volume prevents pinching of liquid and froth flow over the inlet without the need for a stilling deck 114 as shown in FIGS. 2 and 3 . The liquid balancing box 234 , which may be located in the middle of the central downcomer 202 , facilitates liquid communication between the two portions of each central downcomer 202 , which are sloped in different directions. This feature promotes the balancing of the liquid flow in the case that one side of the central downcomer 202 has a higher liquid input or output than the opposite side. The deck portions 206 are similar to deck portions 106 described in the previous embodiment. Further, the central baffle 208 is similar to the central baffle 108 described in the previous embodiment. In another embodiment not shown, the central baffle extends beyond at least one of the downcomers towards the periphery of the tray. This extension of the central baffle ensures a more uniform residence time on the decking located adjacent the perimeter of the tray. As described in the first embodiment, strengthened central downcomers may be used for additional support for the tray 100 . The central downcomers may provide the majority of the support for the contacting tray 200 and since tray efficiency is increased with fewer central downcomers, strengthened central downcomers 202 may be needed. Strengthened central downcomers 202 , as shown in FIGS. 8A and 8B , may be made with two pieces (one with an inclined baffle 220 slanted one way and the other slanted in the opposite direction). Each piece may be made mostly of a single sheet of material that is cut and bent into shape. Thus there are as few joints as possible. The pieces each have a flange 254 that overlaps with the shortened side wall 210 b and the inclined baffle 220 of the opposite piece and cooperates to form a strong joint between the two pieces and also to form a modified liquid balancing box 234 that facilitates fluid transfer between the downcomer sections. The flanges 254 distribute the stress on the joint between the two downcomer pieces and include several slots 256 for liquid flow. Holes are not placed near high stress areas. The top edge of the strengthened central downcomer 202 is folded over and welded for additional strength. Further, cross braces 258 may be included to increase lateral stability of the downcomer and, thus, increase the downcomer strength. In certain embodiments with a substantially large contacting tray (such as those having a diameter of over 16-ft), structural I-beams may be used for additional support for the deck 206 while limiting the adverse affect on tray efficiency that additional downcomers may cause. In order to improve the flow of the liquid around the sides of the tray 200 and increase tray capacity, a third embodiment of the invention combining the first two embodiments is presented. Multiple downcomer trays 300 are shown in FIGS. 9A and 10 . The tray 300 includes at least one central downcomer 302 , each of which is similar in structure to the central downcomer 202 , and side downcomers 304 . The side downcomers 304 are similar in structure to the side downcomers 104 except that the side downcomers 304 may incorporate a sloped side wall to reduce pinching. More particularly, the tray 300 includes a central downcomer 302 with a liquid balancing box 334 , side downcomers 304 , a deck 306 , and a swept-back center baffle 308 ′ similar to the center baffle 108 ′ described in the first embodiment. The tray 300 may alternatively include a straight center baffle 308 , as shown in FIG. 11A . The central downcomer 302 , as well as the side downcomers 304 include an inclined downcomer baffle 320 with anti-penetration weirs 322 . The central downcomer 302 and the side downcomers 304 also include a bottom plate 312 and openings 318 . The side downcomers 304 further include a receiving portion 324 and a distribution portion 326 . The center baffle 308 ′ also includes equalization ports 350 as best seen in FIG. 9B . The equalization ports 350 allow balancing of the liquid flows between the sides of the deck 306 divided by the swept-back center baffle 308 ′. The equalization ports 350 should be kept remote from the downcomer inlets and outlets so they do not form a shortcut for the liquid to flow from an outlet to an inlet without flowing over the majority part of deck 306 . Further, the vapor-liquid mixture is similar on both sides of the baffle 308 ′ in the middle of the deck 306 , remote from the downcomers, whereas the areas proximate to the downcomers have different vapor-liquid compositions on either side of the baffle 308 ′. Particularly, one side of the baffle 308 ′ is proximate a downcomer outlet, while the opposite side of the baffle 308 ′ is proximate a downcomer inlet. The equalization ports 350 may also be used in conjunction with the straight center baffle 308 . Vapor may enter the receiving portion 324 with the liquid in the form of froth. Therefore, it may be necessary to include an outlet path for the vapor in the distribution portion 326 to prevent choking. As shown in FIG. 10 , the outlet path above the distribution portion 326 includes a side wall 351 to prevent liquid from entering and directs the vapor between the side downcomer and the outer perimeter of the tray, that is, along the inner wall of the column. The flow path may continue along the outer wall of the column to the top of the column or the vapor may be vented below a deck portion 306 of a superior tray. A momentum dampening device 352 may be installed in the distribution portion of the side downcomers to reduce the flow momentum of liquid from the receiving portion. A variation of the side downcomers 304 shown in FIGS. 11A and 11B is that the top of the distribution portion 326 is sealed with a flat plate 336 to prevent the liquid from short cutting from the superior downcomer. Further, the center baffle 308 cooperates with the flat plate 336 to prevent liquid deposited on the flat plate 336 from running into the receiving portion 324 . A perforated distribution weir 340 may be included under the distribution portion 326 next to the flat plate 336 of the inferior distribution portion to improve liquid distribution. Alternatively, a bubble promoter 342 may be included instead of the distribution weir 340 . Further methods of maximizing the active area under the distribution portion 326 are shown in FIG. 12 . The first means includes a perforated plate 344 positioned at an angle below the distribution portion 326 . A gap 345 between the deck 306 and distribution portion 326 allows vapor to enter the area under the plate 344 and the perforations allow the vapor to pass through the plate 344 and mix with the liquid deposited on the plate 344 from the superior distribution portion. Alternatively, a perforated flat plate 346 , similar to plate 344 , is used in cooperation with an inclined baffle 320 . In a further alternative, a perforated plate 348 having a combination of slots, louvers, and/or valves is used. The active area may be further increased by including a bubble promoter 342 , with gap 345 , below the outlets of the central downcomer 302 . The bubble promoters may also include an outlet weir 343 . Alternatively, bubble promoter 342 ′ is located below the outlet of the central downcomer 302 . Bubble promoter 342 ′ does not include a gap 345 , however, the portion of the contacting deck 306 under the bubble promoter 342 ′ has much more fractional perforations than the rest of the deck 306 so that the total open area of the deck 306 covered by the bubble promoter 342 ′ is equivalent to or larger than the total open area of the sloped perforated plate on the top of the bubble promoter 342 ′. This alternative provides for easier fabrication and installation. FIG. 13 shows distribution portions 326 having inclined baffles 320 of different inclinations and different distribution weirs 322 . The inclined baffles 320 provide increased volume over the distribution portion 326 to improve vapor venting and to reduce downcomer choking, similarly to the inclined baffles associated with the central downcomers 302 . With reference to line A, one can also see that the receiving portion 324 and the distribution portion 326 of the side downcomer 304 may be designed with different depths to increase downcomer capacity. FIG. 14 shows several varying distribution portions 326 that omit the bottom plate 312 and instead have a side wall that extends to close proximity to the inclined baffle 320 directly below the distribution portion 326 . The side wall leaves a small gap above the baffle 320 in order to allow liquid to escape the distribution portion 326 and not allow vapor to enter into the side downcomer 304 . While the above described methods may have advantages there may also be advantages in particular applications to increase the active area of tray 300 by simply reducing the area of distribution portion 326 . The issue of pinching may alternatively be addressed as shown in FIG. 15 . The Vapor-liquid contacting tray 400 includes at least one stepped central downcomer 402 and a plurality of stepped side downcomers 404 . These stepped downcomers include a stepped side wall 410 that increases the volume over the inlet to an inferior downcomer rather than extending the inclined baffle 420 vertically. Tray 500 , shown in FIG. 16 , comprises further variations of the central downcomers 502 . Side walls 510 are inclined or stepped on both sides of the downcomer to further increase the volume over the deck portions 506 . It should be noted that although several of the figures show downcomers having differing designs on different trays in the same column, it is expected that trays of a similar design will be used in a single column or a section of a column. It should also be noted that although substantially circular contacting trays are shown and described, other shapes, such as polygonal shapes, may also be imagined. The physical size of any portion of a parallel flow multiple downcomer tray must be chosen by a skilled designer considering all aspects of the intended operation of the tray. The spacing between vertically adjacent trays will normally be between 20 and 91 centimeters (8–36 inches) and is preferably between 30–61 centimeters (12–24 inches). The total open area of the deck area is generally in the range of about 5 to about 20 percent. For the deck with sieve holes and slots, the normal hole diameter of the circular perforations may range from about 0.3 to about 2.6 centimeters (⅛–1.0 inches). A hole size of about 0.47 to about 0.64 centimeters ( 3/16–¼ inch) is normally preferred. The open area provided by slots is from about 0.25 to about 5 percent of the area of the deck. A representative thickness of the decking is about 0.19 centimeters (0.075 inches) to 0.34 cm (0.14 inches). The rectangular inlet openings of the central downcomers are normally about 6 to about 25 cm wide (2.5–10 inches). The height of a downcomer as measured from the horizontal top edge of the first side wall to the bottom edge of the first side wall is normally between about 40 to 80% of the spacing between two adjacent trays. This includes the height that the first side wall extends above the decking and below the decking. Thus, the height of the downcomer is equivalent to the overall height of the tallest side wall. The spacing between two adjacent trays is the vertical distance measured between the decking of the two trays. The height of the central liquid/vapor baffle above the decking will normally be approximately 50 to 90% of the spacing between two adjacent trays. The width of the central downcomers may be different from each other depending on their length. The side downcomer is in some embodiments sized such that its top inlet area is similar to top inlet area of the central downcomers. While the invention has been described with reference to particular embodiments, it will be understood by those skilled in the art that the tray may be designed by combining the elements disclosed above and various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the scope of the invention. Therefore, it is intended that the invention not be limited to the particular embodiments disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope and spirit of the appended claims.
The invention comprises multiple configurations of downcomers in a parallel flow multiple downcomer tray for vapor-liquid contacting processes such as the separation of chemical compounds via fractional distillation or the removal of a component of a gas stream with a treating liquid. In one embodiment, side downcomers are incorporated into a parallel flow multiple downcomer tray. In another embodiment, the downcomers have an inclined side wall that directs liquid onto the deck below the downcomer. The inclined side wall also provides additional volume above the inferior downcomer inlet to reduce pinching at this inlet without the need for a stilling deck.
1
This application is a continuation of application Ser. No. 033,793, filed on Apr. 3, 1987, now abandoned. BACKGROUND OF THE INVENTION 1. Field of the Invention This invention has as its object a circuit to perform a linear transformation on a digital signal composed of N digital samples, where N is a whole number. The invention is particularly applicable in the processing of digital signals, for example picture or speech signals, for the coding of these signals before they are transmitted on a transmission line. 2. Discussion of Background In these application, various types of linear transformation are used, such as for example the discrete Fourier transform, the discrete cosine transform, the discrete sine transform, the discrete Hadamard transform, or the like. These transforms are called "discrete" with reference to the digital characteristic of the processed signal. The linear transformation applied to a digital signal of N samples is represented traditionally by a graph in which the branches represent a multiplication operation and the nodes an addition or subtraction operation. Such graphs are described, for a discrete cosine transformation, in the following documents: French patent application No. 85 15649 filed on Oct. 22, 1985, now publication No. 2,589,020. "A fast computational algorithm for the discrete cosine transform" of W. H. CHEN et al, IEEE Transactions on Communication, vol. COM-25, No. 9, Sept. 1977, pages 1004 to 009, A high FDCT processor for real-time processing of NTSC color TV signal" of A. JALALI et al, IEEE Transactions on Electromagnetic Compatibility, vol. EMC-24, No. 2, May 1982, pages 278 to 286, U.S. Pat. No. 4,385,363. The practical embodiment of a circuit based on a linear transformation graph runs into two main problems, which are, on the one hand, the volume of the computations to be performed and, on the other hand, a flood of very complicated data between the various stages of the graph, because of the complexity of this graph. Numerous works have already been done on simplifying the transformation algorithms, i.e., on the graphs, by reducing the number of multiplication operations to reduce the flow of data. Actually, this reduction is desired because the multipliers are the costly elements of the circuit, both as regards their price, and their surface or their consumption. The number of multipliers is therefore reduced to a minimum by assigning to each multiplier the computations of several branches of the graph, so as to obtain a maximum rate of use of each of these multipliers. Two types of circuit for performing a linear transformation, particularly a discrete cosine transformation or a discrete Fourier transformation are known. A first known architecture consists in using a large number of signal processing microprocessors working in parallel. The known architecture consists in using standard multipliers and adders connected to one another. This circuit is described particularly in U.S. Pat. No. 4,385,363 already cited. For these two architectures, it involves an assembly of integrated circuits. It has already also been proposed to make a linear transformation circuit in the form of a specific integrated circuit comprising several multipliers working in parallel. These multipliers are not specialized, i.e., between each other they can multiply any two numbers. Circuits of the prior art exhibit the drawback of using only standard multiplying and adders, which does not make it possible to take into account the specific characteristics of the graph of the transformation that it is desired to achieve. This deviation between the architecture of the linear transformation circuits and the structure of the algorithm represented by the graph does not make it possible to optimize the processing. SUMMARY OF THE INVENTION The object of the invention is to eliminate the drawbacks, particularly the low performance to price ratio, of the circuits according to the prior art. This object is attained by a circuit for performing a linear transformation whose architecture is traced on that of the graph of the transformation. In opposition to the known circuits in which the multipliers and the adders are standard circuits, able to multiply or add any two operands, in the circuit of the invention dedicated adders and multipliers are used. More specifically, a specific multiplier corresponds to each branch of the graph of the transformation, and likewise a specific adder corresponds to each node of the graph of the transformation. Thus, each multiplier must multiply two operands one of which is fixed and represents the weight of the branch of the associated graph. Also, each adder is designed to perform only a single operation of addition or subtraction. The invention therefore has as its object a circuit to perform a linear transformation on a digital signal composed of N samples, where N is a whole number, said circuit comprising a series of stages performing operations of addition and/or multiplication along a determined linear transformation graph, said graph comprising branches each representing an operation of multiplication between a variable operand and a determined coefficient, and nodes each representing an addition or a subtraction between two variable operands, said circuit being characterized in that it comprises a multiplier associated with each branch, this multiplier being wired according to the value of the determined coefficient associated with the branch, and an adder for each node, each adder being wired according to the nature of the operation, addition or substraction, associated with this node. Preferably, the circuit of the invention is made in the form of a single integrated circuit. The circuit of the invention exhibits in particular the advantage, compared with known circuits, of a superior computing power thanks to the parallelism between its architecture and the structure of the graph of the linear transformation that it performs. This also makes it possible, in an integrated version, to optimize the cost by reducing the surface and the number of circuits used, the power consumed and the cost of development. Moreover, the reliability of the circuit is improved by it. The use of as many operators as nodes and branches of the graph makes it possible to obtain in the circuit a flood of uniform data without switching. Moreover, since each multiplier is associated with a single branch, one of its operands is constant. In the case of a discrete cosine transformation, this constant operand is a cosine or a sine. The fact that an operator is constant makes it possible for each multiplier to be specialized. BRIEF DESCRIPTION OF THE DRAWINGS The characteristics and advantages of the invention will come out better from the following description, given by way of illustration, but nonlimiting, with reference to the accompanying drawings in which: FIGS. 1a, 1b and 1c illustrate a graph of a discrete cosine transformation of size 16, FIGS. 2a, 2b and 2c illustrate an embodiment of a circuit according to the invention for putting into practice the transformation represented in FIGS. 1a, 1b and 1c. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS By way of example, a circuit is described that performs the discrete cosine transform in real time for an image organized in blocks of 16×16 pixels. In a known way, the computation flow is optimized thanks to a "pipeline" type structure in which the number of maximum operations that a sample of date must undergo is minimal. Thus, the amount of storages or of buffer registers used is minimized. French patent publication No. 2,589,020, already cited, describes the discrete cosine transformation graph for the transformation of a line or a column of 16 pixels. This graph is reproduced in FIGS. 1a, 1b and 1c. The discrete cosine transformation circuit of a block of 16×16 pixels is made in the form of a single integrated circuit comprising, in order, the following modules: an input register array performing the conversion of 16 pixels received in sequence and coded in parallel, into 16 pixels delivered bit by bit, in series, a computation operator of the discrete cosine transformation of a line of a block of 16×16 pixels, a storage and transposition register array which is used to store the line discrete cosine transformation coefficients of the entire block before accessing the column discrete cosine transformation computations. To do this, the various coefficients which arrive line after line must be rearranged by column. The use of a register array with horizontal and vertical shift and of input and output multiplexers makes it possible to use only a single storage array, a computation operator of the discrete cosine transformation of a column of a block of 16×16 pixels, an output register array which performs an inverse series-parallel conversion of it made by the input register array. The computation operators of the discrete cosine transform of a line or of a column are each in accordance with the graph represented in FIGS. 1a, 1b, and 1c. In this graph, each node represents an addition operation between the branches which end at this node, and each branch represents a multiplication of the number applied to the input of the branch by the coefficient associated with this branch. The coefficients designated Ciπ and Siπ correspond respectively to cos(iπ) and sin(iπ). French patent application No. 85 15649 can be consulted for a more detailed description of the graph. An embodiment according to the invention of a computation operator is represented in FIGS. 2a, 2b and 2c. In this embodiment, each operator comprises 44 multipliers of the parallel-series type and 72 adders of the series type. For each multiplier, the multiplying coefficient applied to the data received as input has been indicated. For each adder, the nature of the operation --addition or subtraction --has been specified by the the signs "+" and "-". In the case of a subtraction, the operand applied to the lower input of the subtracting device is subtracted from the one applied to its upper input. The parallel-series multipliers work with multipliers coded in 2's complement code and are delivered with the least significant bit (LSB) at the head. For each multiplier, the multiplicand which represents a cosine or sine coefficient is positive and wired to an adder of the modified "Manchester Carry Chain" type, to take into account the fact that this multiplicand is fixed. Besides the computing operator itself, each multiplier comprises an accumulation and shift register, and a buffer register to deliver the data bit by bit to the following computing stage in the graph. This register of the parallel-series type further comprises an inverter making it possible to provide the result to the following stage with the appropriate sign. The adders are of the series type and work also on operands coded in 2's complement code. Each adder is wired so as to perform, between the two operands, the desired addition or subtraction operation. Additional buffer registers BUFF can be used to keep the data which is unchanged between two nodes. According to the invention, and addition or multiplication operator is associated with each node or each branch of the graph. In practice, it is sometimes possible to simplify slightly the circuit associated with the graph. For example, in FIG. 1b, two branches associated with the same multiplicative coefficient cos( π/4) proceed from the same node d 6 . Of course, it is useless to provide two identical multipliers for the same node. Therefore, in FIG. 2b a single multiplier receiving the signal from node d 6 has been provided, the result of the multiplication being transmitted simultaneously to the adders corresponding to nodes e 5 and e 6 . The procedure was the same for the branches coming from node d 5 . However, in this case, the multiplicative coefficient is equal to +cos(π/4) for one branch and to -cos(π/4) for the other branch. The multiplier used has a multiplicative coefficient of cos(π/4); the minus sign which must be added for the branch going from d 5 to e 5 is restored by replacing the adder with a subtracting device at e 5 . Moreover, it is noted that it is possible to make in any circuit only multipliers having a positive multiplication coefficient, the possible sign of this coefficient being taken into account during the addition/subtraction operation which follows. The applicant has made an integrated circuit for the discrete cosine transform described above. This circuit comprises 80,000 transistors on a 49 mm 2 chip. This circuit is made in a 2 micron CMOS technology with two metallization levels. The discrete cosine transform of a block of 16×16 pixels, each coded on 8 bits, is achieved in real time at a frequency of 16 megahertz and with an internal precision of the computations on 14 bits.
A circuit which performs a linear transformation on a digital signal. A linear transformation is defined by a graph whose nodes represent operations of addition or subtraction and the branches operations of multiplication by a determined coefficient. According to the invention, the circuit comprises a multiplier for each branch, this multiplier being wired according to the value of the determined coefficient of said branch, and an adder for each node, each adder being wired according to the nature of the operation, addition or subtraction, associated with said node.
6
This application claims the benefit of and is a National Phase Entry of International Application Serial Number PCT/CA2004/001935, filed Nov. 4, 2004. This application also claims the benefit of U.S. Provisional Patent Application 60/516,874, filed on Nov. 4, 2003, from which PCT/CA2004/001935 claims priority. The International Application PCT/CA2004/001935 and U.S. Provisional Application 60/516,874 are hereby incorporated herein by reference. FIELD OF THE INVENTION This invention relates generally to framed panels and fenestration products and more particularly but not limited to products made from thermoplastic profiles welded around an insulating glass unit. BACKGROUND OF THE INVENTION To improve manufacturing efficiency and reduce product costs, various attempts have been make in recent years to develop integrated insulating glass/window frame production systems. One example which is described in a presentation given at InterGlass Metal 97' was developed in Germany by Meeth Fenester. With this production system, the window is, fabricated from plastic channel window frame profiles that are assembled around an insulating glass (IG) unit and corner welded using conventional hot plate technology. During the assembly process, the unit is held in position by means of a hot melt butyl adhesive bead that is located centrally in the frame channel. Twin silicone thermosetting glazing sealant beads are then applied in the two gaps either side of the IG unit. After assembly, the windows are stored in a truck container ready for shipping and the truck containers are left-parked outside the factory for a few hours while the two-part silicone sealant is cured. For the Meeth production system, there are four main drawbacks. First, because of the butyl adhesive bead, the glazing channel cannot be drained and this creates potential IG durability problems. Second, conventional hot plate welding is a slow process that is complicated by the need for corner flash removal. Third, the sash frame assemblies cannot be shipped until the two-part thermosetting sealant is fully cured. Fourth, the Meeth production is largely a manual process with manual loading of the individual frame profiles into the welding clamping fixtures and manual application of the sealant beads. A second example of an integrated IG/window frame system is described in U.S. Pat. No. 5,622,017 issued to Lynn et al. and assigned to the Andersen Corporation. As with the Meeth system, the Andersen window is also fabricated from plastic channel frame profiles that are assembled around an IG unit and corner welded using conventional hot plate technology. In comparison with the Meeth System, the Andersen profile incorporates conventional plastic glazing fins on one side of the channel frame profile. A structural thermosetting sealant is then applied to one side of the unit and the single glazing sealant bead is allowed to cure. Because the IG glass unit is not held in position, the frame subassembly cannot be moved for several hours while waiting for the sealant to cure. In addition, the unit cannot be accurately centered within the channel profile and so the process of sealant application cannot be easily automated. As described in U.S. Pat. No. 5,902,657 issued to Hanson et al., the channel frame profiles can be joined at the corners using friction welding with a moveable U-shaped metal platen that rapidly moves back and forth melting the plastic at the interface joint. As with conventional hot plate welding, the metal platen is then removed and the matching ends of the framing profiles are then pressured against each other. From a practical perspective, this solution is difficult to implement because as the metal plate is removed, the molten plastic material is also removed resulting in a poor weld assembly. A further concern is that the IG unit is held in position by the sloped channel walls and as a result there are potential glass breakage problems at the corners. A third example of an integrated IG/window frame system is described in PCT application CA02/000842 by Field et al (See FIGS. 21-23 therein). Again, the frame assembly is welded using friction welding but instead of using a metal platen, a plastic web is used that is vibrated back and forth using an inverted vibratory welding head. To avoid potential glass breakage problems, the IG unit is isolated from the plastic channel frame profiles using conventional rubber setting blocks. However, because the unit is not firmly held in position and is not accurately centered, the sealant application process cannot easily be automated. In addition, the profiles have to be manually loaded into the clamping fixtures and this slows down the production cycle time. SUMMARY OF THE INVENTION According to one aspect of the present invention, there is provided a framed panel unit comprising a panel; a plurality of thermoplastic frame members disposed along the edge of said panel; each frame member having first and second opposed side walls defining a channel therebetween, the edge of said panel being received within the channel of each frame member; the channel of each frame member having spacer means therein including a first spacer between said panel and said first side wall for spacing said panel from said first side wall and a second spacer between said panel and said second side wall for spacing said panel from said second side wall, and where prior to welding together the ends of said frame profiles, the spacer means retain frame members on the panel. One preferred arrangement is where at least one of said first and second spacers is positioned below the top of a respective channel wall to provide an open gap at the top of the channel between the panel and the side wall for receiving sealant. Advantageously, in this arrangement, spacers are provided in the channel, either side of the panel to center the panel in the channel and to also hold the panel in position during an assembly process, for example during application of a sealant, e.g. a reactive thermoplastic sealant, to both sides of the panel along a frame member. In this arrangement, the spacers also resiliently retain the frame members on the panel when the frame members are unconnected so that the frame members can be positioned and held in place on the panel before the frame members are connected together, for example by welding. This also facilitates handling of the unit by allowing the various components to be moved and transferred together as whole between assembly stations in a production process and, in particular, facilitates the transfer and loading of the frame members into a welding apparatus so that this loading process may be automated, rather than manual. One or both spacers may be formed separately from the frame member, or may be formed integrally therewith. One or both spacers may comprise a discrete protrusion extending into the channel for engaging a portion of the panel adjacent an edge thereof. Either one or each protrusion may have an upper surface which is deflected downwards to engage the surface of the panel so that when the pressure applied to the panel by the protrusion is increased if the frame member is pulled in a direction away from the panel, making it difficult to withdraw the frame member from the panel when installed thereon. When separately formed from the frame members, the first and second spacer may be joined together by a third intermediate spacer which spaces the edge of the panel from the base of the channel. The first, second and third spacers may thereby form a U-shaped insert and the first and second spacers may be hingedly coupled to the third spacer and may be integrally formed therewith. The spacer insert may include locator means for positioning the insert at a predetermined lateral position between the side walls of the channel, which is particularly advantageous when, due to manufacturing tolerances, the distance between the side walls of the channel are greater than required to accommodate the width of the insert. In one embodiment, the base of the channel has oppositely sloped upper surfaces which slope transversely of the channel and the locator means includes first and second oppositely sloped lower surfaces of the third spacer which engage the sloped surfaces of the channel to urge the third spacer towards a predetermined position within the channel on applying a force, for example the weight of the panel, to the third spacer towards the base of the channel. In one embodiment, the frame members are welded together by friction welding, and preferably by means of a weldable junction piece disposed between adjacent ends of the frame members. The junction piece may be a flat planar flange or may also incorporate integral legs that help position the framing members in the assembly process. In one embodiment, the framed panel unit includes a reactive thermoplastic sealant material along the junction between one or both outer surfaces of the panel and the frame member. The sealant material may have a high degree of stiffness (high modulus) to increase the structural strength and rigidity of the framed panel unit. The reactive thermoplastic sealant may for example be polyurethane or silicone based. Advantageously, as the spacers effectively position and hold the panel in the desired position, relative thereto, the sealant need not have any open time to allow the panel to be repositioned relative to the joined frame members, and no repositioning is required. This allows a warm or hot applied thermoplastic sealant to be used which cools down almost immediately on its application to the panel unit so that once the application process is complete, the unit can be moved almost immediately to the next production stage, if any, for shipment, or for storage, resulting in a fast and more efficient production process. In one embodiment, the sealant may comprise a reactive thermoplastic sealant that may have an open time of 2 seconds or less but which after exposure to moisture chemically cures and bonds to the glass. According to another aspect of the present invention, there is provided a panel unit comprising first and second opposed sheet members; a spacer between said sheet members spacing said sheet members apart, said spacer comprising a thermoplastic sealant material and being located proximate an edge of the sheet members; a frame member having a channel formed therein, said edge being disposed within said channel; and a reactive thermoplastic sealant material bonding said sheets to said frame member. Advantageously, the provision of a reactive thermoplastic sealant material which structurally bonds the sheets to the frame member allows the perimeter seal and spacer between the sheet members to be simplified and the material used to be considerably reduced. In one embodiment, the perimeter edge seal between the glazing sheets only consists of a thermoplastic sealant spacer. According to another aspect of the present invention, there is provided a method of forming a framed panel, comprising the steps of: (a) providing a panel to be framed; (b) providing a plurality of frame members for framing said panel, each frame member having a channel formed therein for receiving an edge portion of said panel and resilient means within said channel for spacing the panel from opposed side walls of said channel and for resiliently retaining said panel in said channel; (c) inserting said panel into the channel of each frame member such that said frame members are held on said panel by said resilient means; and (d) joining the ends of adjacent frame members together by welding. In one embodiment, the framing members are interconnected by junction pieces prior to transferring the frame/panel subassembly to the welding apparatus. According to another aspect of the present invention, there is provided a frame member for a panel, comprising first and second opposed side walls defining a channel therebetween for receiving said panel; first and second pre-formed spacers comprising a resilient material inserted in said channel; the first spacer being positioned against said first side wall for spacing one side of said panel therefrom and said second spacer being positioned against said second side wall to space the other side of said panel therefrom. According to another aspect of the present invention, there is provided a spacer component for use in mounting a panel within a channel of a frame member, comprising a base portion for spacing said panel from the base of said channel; a side portion extending from said base portion for spacing said panel from a side wall of said channel; and a protrusion extending from said side portion for engaging a face of said panel and for resiliently retaining said panel in said frame member. According to another aspect of the present invention, there is provided a frame member comprising first and second opposed sidewalls defining a channel therebetween and protrusions extending from each sidewall into said channel for resiliently retaining a panel therebetween. In one embodiment, the protrusions that extend from each side wall are flexible fins and according to another embodiment, a bulb seal also extends from each side wall and is located at the top of each framing channel member. According to another aspect of the present invention, there is provided a frame member comprising first and second opposed sidewalls defining a channel therebetween, at least one sidewall having an elongate recess formed therein extending along the channel and positioned below the top of a respective sidewall. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows an exploded elevation view of U-channel sash frame profiles assembled around an insulating glass panel. FIG. 2 is a vertical cross section perspective corner detail of a U-channel sash frame incorporating a double glazed insulating panel. FIG. 3 is a perspective view of a single corner vibration welding apparatus. FIG. 4A is a plan view of a single corner, vibration welding apparatus with the extrusions installed in the fixtures prior to the welding process. FIG. 4B is a view similar to FIG. 4A showing the single corner vibration welding apparatus during the welding process. FIG. 5 shows a cross section sash frame detail of a U-channel sash frame profile incorporating a conventional dual-seal insulating glass panel and where the framing profiles are temporarily held in position by means of folding rubber spacer inserts. FIG. 6A is a perspective view of the folding rubber spacer inserts prior to insertion within the U-channel sash frame profile. FIG. 6B is a perspective detail view of the folding rubber spacer inserts after insertion within the U-channel sash frame profile. FIG. 7A shows a cross section detail of the folding rubber spacer and the perimeter edge of an insulating glass panel just prior to the insertion of the panel into the folding rubber spacer. FIG. 7B is cross section detail of the perimeter edge of an insulating glass panel after the panel has been inserted into the folding rubber spacer. FIG. 8A shows an exploded cross section detail of three window sash frame components, including: (i) bottom perimeter edge of insulating glass panel, (ii) an unfolded rubber spacer insert and (iii) U-channel sash frame profile. FIG. 8B shows a cross section detail of the folding rubber spacer inserted within the U-channel sash frame profile. FIG. 8C shows the insulating glass panel inserted within the U-channel sash frame profile. FIG. 9 shows a cross section detail of the perimeter edge of a single-seal insulating glass panel incorporated within a U-channel sash frame profile. FIGS. 10A-10D show schematic plan views of the production process of an integrated IG/window frame assembly. FIG. 10A shows a schematic plan view of the insulating glass panel. FIG. 10B shows a schematic plan view of the insulating glass panel with U-shaped plastic framing profiles loosely assembled around the insulating unit. FIG. 10C shows a plan view of the insulating panel/plastic sash frame subassembly with junction pieces inserted at the corners. FIG. 10D shows a plan view of the completed window sash subassembly. FIG. 11A is a cross section plan view detail of a frame corner assembly where the thermoplastic plastic profiles are vibration welded at the corner using a corner junction piece with a diagonal web and integral legs. FIG. 11B is a cross section detail of the frame corner assembly as shown in FIG. 11A where the plastic framing profile is ultrasonically spot welded to the integral legs of the corner junction piece. FIG. 11C shows a vertical cross-section detail through the hollow profile shown in FIG. 11A . FIGS. 12A-12E show schematic plan views of a high volume production process of an integrated IG/frame assembly. FIG. 12A shows a plan view of the frame profiles assembled around an insulating glass panel. FIG. 12B shows a plan view of the insulating glass panel/frame subassembly. FIG. 12C shows a plan view of the insulating glass panel/frame subassembly suspended below a gantry. FIG. 12D shows a plan view of a four headed horizontal friction corner welder with the insulating glass panel/frame assembly dropped into position. FIG. 12E shows a plan view of the four headed horizontal friction corner welder with the insulating glass panel/frame assembly clamped into position just prior to the welding process. FIG. 13 is a vertical cross section of a U-channel sash frame window incorporating a double glazed insulating panel and thermoplastic U-channel framing profiles with integrally formed flexible fin spacers and glazing bulb seals. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawings, FIG. 1 shows an exploded elevation view of a sash window 20 where the U-shaped thermoplastic framing profiles 21 are assembled around an insulating glass panel unit 25 . Typically, the insulating glass panel unit 25 consists of two glass sheets 26 , 27 , which are shown more clearly in FIG. 5 , and are separated by a perimeter edge seal. As described in more detail in FIGS. 3 to 5 , the end joint surfaces 23 , 24 of the sash frame profile members 21 are friction welded at the corners using thermoplastic planar flange junction pieces 22 . Folding rubber spacer inserts 30 are used to hold the insulating glass panel 25 in position within the U-shaped channel profile 21 . Prior to the welding process, the folding rubber spacer inserts 30 also retain the framing profiles 21 in position on the insulating glass panel 25 . In addition, the folding rubber spacer inserts 30 also prevent the vibrating junction piece 22 from striking the corners 31 of the insulating glass panel 25 during the welding process. The folding rubber spacer inserts 30 can be made from various resilient materials with one preferred material being EPDM rubber. FIG. 2 shows an exploded perspective corner detail of a U-channel sash frame window 20 incorporating a double glazed insulating panel unit 25 . The ends 23 , 24 of the plastic framing profiles 21 are miter cut and vibration welded to a plastic planar flange junction piece 22 . The framing profiles 21 can be made from various thermoplastic materials but generally, the preferred material is polyvinyl chloride (PVC). In order for the junction pieces 22 to strongly bond to the framing profiles 21 , the junction pieces 22 are made from essentially the same type of plastic material as the framing profiles 21 . FIG. 3 shows a top perspective view of a prototype single corner vibration welding apparatus 32 . The apparatus consists of five main components: 1. Vibratory Head A linear vibratory head 33 that incorporates a top plate 34 which vibrates back and forth very rapidly in a predetermined plane. 2. Junction Piece Holding Fixture A junction piece holding fixture 35 which is directly attached to the top plate 34 and firmly holds the planar flange junction piece 22 in position. 3. Moveable Framing Fixtures Two moveable framing fixtures 36 and 37 incorporate clamping devices 38 that firmly hold the framing profiles 21 in position. 4. Control Systems A control system 39 that regulates the various operating parameters of the vibration welding apparatus 32 including: weld time, hold time, joint pressure, weld depth, amplitude, frequency and voltage. 5. Machine Frame A machine frame 40 which provides the structure that supports the other components. FIG. 4A shows a plan view of a single corner, vibration welding apparatus 32 in an open position. The linear vibration welding apparatus 32 features a vibratory head 33 that linearly moves back and forth in a pre-determined plane. The vibratory head 33 is similar to the vibratory heads used on commercially available linear vibration welders such as the Branson Mini Welder, but unlike these commercially available products, the vibratory head is turned upside down as this allows for more flexible and easy positioning of the framing profile members 41 and 42 during the frame assembly process. A flat plate 43 is bolted to the top surface of the vibratory head 33 . As with standard vibration welders, the vibratory head 33 is bolted to a separate heavy cast iron support (not shown) and isolated from the cast iron support structure (not shown) using rubber mounts. This cast iron support structure is in turn bolted to a machine frame 40 that positions the vibratory head 33 at a convenient working height. Flat plate metal sheets 44 are bolted to the top surface of the machine frame 40 but this top working surface is separated apart from the vibratory head 33 so that a minimum of vibratory movement is transferred to the machine frame 40 . Moveable profile fixtures 36 and 37 are supported on guide rails 45 directly attached to the top table plate 44 and these fixtures hold the framing profiles 41 and 42 in position. The moveable profile fixtures 36 and 37 move over the vibratory head 33 but there is no direct contact except where the framing profiles 41 and 42 contact the junction piece 22 . The moveable fixtures also allow for the miter cut ends 23 , 24 of the framing profiles 41 and 42 to be positioned parallel to the planar flange 48 of the junction piece 22 . A fixed holding fixture 35 for the junction piece 22 is located so that the planar flange 48 of the junction piece 22 is in a balanced central position. The holding fixture 35 which is directly attached to the top plate 43 of the vibratory head 33 , firmly holds the removable tab 49 of the junction piece 22 in position. FIG. 4B shows a plan view of the vibration welding equipment 32 in operation with the miter cut ends 23 and 24 of the framing profiles 41 and 42 being pressured against the planar flange 48 of the junction piece 22 . By vibrating the junction piece 22 back and forth and by simultaneously pressuring the framing profiles 41 and 42 against the planar flange 48 of the junction piece 22 , friction heat is generated at the two joint interfaces 50 and 51 . When a molten state is reached at the two joint interfaces 50 and 51 , the vibration is stopped and the perpendicular pressure is then maintained briefly while the molten plastic solidifies to form two welded joints 52 and 53 on either side of the planar flange 48 . In order to provide for even weld strength, essentially the same perpendicular engagement force has to be simultaneously applied to each side of the junction piece 22 . One of the key advantages of vibration corner welding is that by incorporating flash traps or weld beads within the junction piece 22 , it is feasible to eliminate the need for mechanical flash removal and as a result, there are substantial equipment cost savings. Although frame assemblies can be manufactured using a single corner welder, it is more productive if two or more corners are welded simultaneously. The operation of a vertical four head welder is described in PCT Application CA02/00842 by Field et al. As with conventional hot plate welders, the profiles are separately loaded into the holding fixtures and the miter cut corners are welded in either a one stage or two stage operation. With a two stage process, two diagonally opposite corners and are first welded together. For each corner weld, the process is essentially the same as with a single corner vibration welder. Both sets of framing profiles are independently pressurized against the two diagonally opposite junction pieces. The next step is for the other set of diagonally opposite corners to be welded together and the assembled frame is then unloaded. Because the friction welding process is so fast (3 to 6 seconds), this two stage process does not significantly increase cycle time and compared with simultaneously welding all four corners, the key advantage is that the required movement and control of the heads is greatly simplified. For a conventional four head, hot plate welder, the overall cycle time is about 2 minutes and this overall cycle time includes: profile loading, corner welding, cool down and frame unloading. In comparison, the overall cycle time for the two-stage vibration welding process is less than 30 seconds and so this represents a significant increase in productivity. Instead of a two stage process, a second option is to simultaneously weld all four corners in one operation. During the vibration welding process, each head has to move fractionally and because the head movements involved are so small and so complex, the control system for this simultaneous four headed welding operation is very complex and requires very sophisticated software. A further major advantage of vibration corner welding is that it is feasible to weld around an insulating glass unit. With a four headed welder, the frame profiles are loaded into the framing fixtures and the insulating glass unit is positioned between the four welding heads. The four heads then move centrally into position so that the U-shaped framing profiles overlap the perimeter edge of the insulating glass unit. With the insulating glass unit in position, the miter cut frame profiles are then welded using friction corner welding. FIG. 5 shows a bottom cross section detail of a U-channel sash window 20 . The U-shaped channel sash framing profiles 21 are assembled around a dual seal insulating glass panel unit 25 . The two gaps 57 and 58 between the insulating glass panel unit 25 and the framing profile 21 are filled with glazing sealant material 59 forming glazing beads 54 and 55 . Various glazing sealant materials can be used but one preferred material is a reactive thermoplastic sealant. Compared to conventional two-part thermosetting sealants, the advantage of a reactive thermoplastic sealant is that the one part sealant is warm or hot applied so that after a few seconds cool down, the material develops high green strength allowing the window units to be almost immediately handled. Compared to conventional widow glazing seal application where there is a need for some open time during the application process, the open time for the reactive thermoplastic sealant materials can be less than two seconds. In addition through a moisture cure process, the reactive thermoplastic material is chemically cured creating a strong adhesive bond between the glass sheets and the framing profiles. Various types of reactive thermoplastic sealants can be used but one preferred material is a reactive hot melt polyurethane adhesive that is manufactured by National Starch and Chemical Company under the trade name of Purfect Glaze. A second preferred material is a reactive hot melt silicone that is manufactured by Dow Corning under the trade name of Instant Glaze. Compared to the reactive silicone material, the reactive polyurethane material generally provides for higher adhesion strength. The modulus or stiffness of the Purfect Glaze sealant can be varied and generally, a high modulus material is preferred as this allows for the glass sheets to be firmly bonded to the framing profiles. As a result, structural advantage can be taken of the stiffness of the glass sheets 26 , 27 so that the structural performance of the framing profiles 21 is enhanced allowing for a reduction in profile size as well as the possible elimination of metal reinforcement that is typically required for large size PVC windows. With a high modulus, stiff sealant material and because of the high differential expansion between the plastic PVC framing profiles 21 and the glass sheets, 26 , 27 there is potential for cold temperature glass breakage. However, our experience has shown that even at quite extreme Canadian winter temperatures (ie below −30° C.) glass breakage is not a problem. This is because the plastic PVC material is sufficiently ductile that differential expansion within the plastic profile cross section can be accommodated. As well, the plastic framing profiles 21 are firmly adhered to the perimeter side faces of the glass sheets 26 , 27 as opposed to the bottom edge where glass breakage problems are accentuated due to glass edge micro cracks created during the glass cutting process. At cold outside temperatures, a further concern is that there can be IG edge seal failure due to loss of adhesion between the glass sheets 26 , 27 and an IG edge spacer. To eliminate this problem, there is a need for the perimeter edge seal to be somewhat flexible and for a conventional dual-seal design. One preferred option is use an inner desiccant-filled PIB/butyl spacer 62 that is backed by outer structural thermosetting sealant 63 . Other IG dual-seal options include: flexible desiccant-filled silicone or EPDM rubber foam spacer (Trade name: Super Spacer) backed by hot melt butyl sealant. Folding rubber spacer inserts 30 are used to accurately center the insulating glass panel unit 25 within the frame profile 21 . These inserts 30 temporarily hold the framing members 21 on the panel unit 25 and also positions the panel 25 in the sash frame subassembly while it is transferred to the sealant gunning application station. The bottom sides 64 and 65 of the U-channel frame profile are chamfered and this helps position the folding rubber spacer inserts 30 within the sash frame profile 21 . To further help hold the folding rubber spacer inserts 30 in position, the sidewalls of the profile also incorporate inner ledges 66 and 67 . The bottom section of the folding rubber spacer inserts 30 also incorporate a V-shaped opening that provides for water drainage from the glazing cavity 69 . To provide for consistent application, the sealant beads 54 and 55 , are produced using robotic application equipment. One option is separately apply each bead using a standard robot and where the sash assembly frame is rotated through 180° degrees after the application of the first bead 54 . A second option is to apply both beads 54 and 55 , simultaneously using automated double-head sealant application equipment that operates in a similar manner to automated sealant gunning equipment used for insulating glass sealing. For double bead application, the sash frame assembly is typically in a vertical position and to ensure that the sealant material does not deform or drip particularly on the top edge, the thermoplastic sealant material needs to have a high viscosity. FIG. 6A shows a perspective view of the folding rubber spacer insert 30 prior to installation within the U-channel profile 21 . The side wall sections 72 and 73 space the IG unit 25 away from the channel walls of the framing profile. The folding rubber spacer insert 30 incorporates V-notches 70 and 71 , that allow the rubber spacer insert to be folded at the corners. The purpose of the V-notches 70 and 71 , is to allow the inserts 30 to be easily installed within the frame profile 21 prior to the insertion of the IG panel 25 . The V-notches 70 and 71 also help the folding rubber spacer insert 30 accommodate dimensional tolerances in the frame profile. The rubber inserts 30 can be made from a variety of different rubber materials with one preferred option being EPDM rubber. Although a one piece assembly is shown in FIG. 6A , it can be appreciated by those skilled-in-the-art that the side wall sections could consist of two separate spacers that are individually attached to the side walls of the channel profile. Similarly the bottom section of the folding rubber spacer insert could also consist of a separate spacer that is positioned in the bottom channel of the framing profile. FIG. 6B shows a perspective view of the folding rubber spacer insert 30 with side sections 72 and 73 folded at right angles to the bottom section 74 . FIG. 7A shows an exploded cross section detail of the folding rubber spacer insert 30 and the perimeter edge 75 of an insulating glass unit panel 25 just prior to the insertion of the panel unit 25 into the folding spacer insert 30 . FIG. 7B is a cross section detail of the perimeter edge 75 of an insulating glass panel 25 after the panel has been inserted into the folding rubber spacer insert 30 that is held within a U-channel frame profile (not shown). The side wall sections 72 and 73 of the folding rubber spacer insert 30 incorporate a protrusion or positioning flange 76 that extends beyond the inner wall surfaces 77 of the side walls 72 and 73 . As the panel unit 25 is inserted into the folding rubber spacer 30 , the protrusion 76 is compressed downwards and so as a result, the insulating glass panel 25 is firmly wedged in position and centered within the frame profile 21 . FIG. 8 shows the production steps involved in the fabrication of the integrated IG/sash frame assembly 20 . FIG. 8A shows an exploded bottom cross section detail of a window sash frame. There are only three components shown: an insulating glass panel 25 , a folding rubber spacer insert 30 and a U-channel sash frame profile 21 . The bottom faces 78 of the rubber spacer insert 30 are coated with a low-friction coating 79 (see dotted line). The low friction coating 79 allows the rubber spacer insert 30 to slide along the U-channel framing profile 21 during the friction corner welding process. The low friction coating 79 is compatible with standard IG sealant materials and one preferred material option is a polyurethane-based coating. In comparison, the top faces 109 of the rubber insert 30 preferably have a high friction coefficient and do not move in position during the friction corner welding process. FIG. 8B shows an exploded bottom cross section detail of a window sash frame with the folding rubber spacer insert 30 inserted within the sash frame profile 21 . The rubber spacer inserts 30 can be inserted manually or alternately, the spacer inserts 30 can be automatically inserted as part of the profile cutting and fabrication process. FIG. 8C shows a bottom cross section detail of a window sash frame 20 with the IG panel unit 25 installed within rubber spacer insert 30 that is held in position within the sash frame profile 21 . The rubber spacer inserts 30 center the IG panel unit 25 in the sash frame 21 and the corners of the frame assembly are then welded using friction corner welding techniques that are described in PCT Application CA02/000842. As well as centering the panel unit 25 , the rubber spacer inserts 30 also help isolate the IG unit 25 from any resonance or vibratory movement during the welding process. The sash frame assembly is then transported to the automated frame sealing robot (not shown) with the rubber spacer inserts 30 holding the IG unit 25 in position. It should be noted that although the friction corner welding process is carried out with the IG panel unit 25 in either a horizontal or vertical position, the sealant gunning operation is typically carried out with the panel unit 25 in a vertical position. By positioning the IG panel unit 25 in a vertical position, this ensures that the IG panel unit 25 is centered within the frame profile 21 and that there is no compression of the bottom rubber side wall sections 72 and 73 . After the double bead application of the reactive hot melt sealant, the sash frame assembly can be immediately transferred to the next step in the production process which is typically hardware application. As a result through these various improvements in assembly methods, there is a continuous sash frame production process with increased throughput and productivity and no major production bottlenecks or delays. Although a double glazed panel unit is illustrated in FIG. 8 , it can be appreciated by those skilled-in-the-art that a triple glazed unit could also be used. Alternatively using a different frame profile, the same production method can be used for welding around a single glass sheet and one option is for this single glass sheet would be as the center light of a triple glazed panel unit. FIG. 9 shows a cross section bottom detail of a single seal IG panel unit 80 incorporated within a slim-line U-channel sash frame profile 81 . In contrast to a dual seal IG unit, the perimeter edge seal assembly 82 consists of a single barrier seal. Various single seal assemblies can be used including: the Intercept™ edge seal product marketed by PPG Inc. and the Swiggle Seal™ product marketed by TruSeal Inc. One preferred single seal design is to use a thermoplastic spacer 83 that is made from desiccant filled butyl and/or polyisobutylene sealant material. The thermoplastic spacer 83 is marketed under the trade name of TPS and is directly applied to the glass using automated sealant gunning equipment manufactured by Bystronic Inc. A key advantage of the TPS spacer is that the material remains somewhat flexible and as a result, the spacer/edge seal assembly can accommodate some degree of glass movement and bowing even at cold temperatures. Typically, the TPS spacer is backed up by a structural thermosetting sealant such as polysulphide or polyurethane sealant (See FIG. 5 ). However with integrated IG/sash frame assembly, the glass sheets 26 and 27 , are structurally bonded to the frame profile 81 by means of structural sealant glazing beads 54 , 55 and so as a result, there is no need for an outer structural IG sealant to hold the glass sheets 26 and 27 in position. By eliminating this outer structural sealant, there are material and equipment cost savings and as well, the frame profile size can also be reduced resulting in additional material cost savings. A further production benefit is that there are no delays while waiting for the thermosetting sealant to cure and this provides for continuous sash frame production with the resulting productivity improvements and cost savings. FIG. 10 shows the key production steps for assembling U-channel sash frame profiles 21 around an insulating glass panel unit 25 . FIG. 10A shows a schematic plan view of an insulating glass panel unit 25 . FIG. 10B shows a schematic plan view of the insulating glass panel unit 25 with U-shaped plastic framing profiles 21 loosely assembled around the insulating glass panel unit 25 . FIG. 10C shows a schematic plan view of the insulating glass unit/frame profile sub assembly 87 with corner junction pieces 22 inserted between the cut ends 23 and 24 of the framing profiles 21 . The four corners of the sash frame subassembly 87 are then welded, using methods and techniques disclosed in PCT CA 02/000842 for example. FIG. 10D shows a schematic plan view of the completed sash frame window 20 . As previously explained, the insulating glass panel unit 25 is held in position and centered in the U-shaped frame profile 21 using folding rubber spacer inserts (not shown). Although the production process is shown in schematic form in FIG. 10 , it can be appreciated by those skilled-in-the-art that the process can be fully automated using four headed production equipment as described in PCT Application CA02/000842. With a conventional, four headed hot plate welder, the overall cycle time is approximately 120 seconds and the time taken to manually load the four plastic profiles into the clamping fixtures is approximately 15 seconds. With four headed friction corner welder, the overall cycle time is less than 30 seconds but the task of manually loading the profiles takes 15 seconds while the actual weld time is less than 2 seconds. Instead of preloading the profiles into the clamping fixtures of the four headed welder, one option with friction corner welding is to loosely fit the profiles around the insulating glass unit (See FIG. 10B ). The profiles 21 can be temporarily held in place, by the folding rubber spacer inserts 30 (not shown) allowing the sub assembly of IG unit/frame profiles 87 to be transferred to the four-headed welder. The planar flange junction pieces 22 are then inserted and the corners welded using friction corner welding techniques. (See FIG. 10C ). As a result of pre-assembling the frame profiles 21 around the IG panel unit 25 , the overall cycle time can potentially be reduced to less than fifteen seconds. Finally, it should be noted that in FIG. 10 although schematic plan views are shown with the insulating glass panel unit 25 in a horizontal position, the various manufacturing operations can also be carried out with the insulating glass panel unit 25 in a vertical position. Where a thermoplastic sealant spacer is used, the sealant is preferably applied directly onto the perimeter glass edge with the glass sheet in a vertical position. As previously noted, the double bead sealant gunning operation is also carried out with the IG/frame sub assembly in a vertical position and so if all the various assembly operations are consistently carried out with the glass sub assemblies in a vertical position, there are potential productivity improvements and cost savings. FIGS. 11A and 11B show a cut out cross section plan view of a corner frame assembly 89 fabricated from square profile glass fiber filled PVC profile extrusions 90 and 91 and where the profiles 90 and 91 are vibration corner welded at using a junction piece 92 incorporating integral legs 93 . As shown in FIG. 11A , the integral legs 93 of the junction piece 92 incorporate an integral spring centering device 94 that simplifies frame assembly. The planar flange 48 of the junction piece 92 is first vibration welded to the miter cut ends 23 and 24 of the profiles 90 and 91 . Because of the need to accommodate the vibration movement back and forth, the legs 93 only loosely fit within the profile. As shown in FIG. 11B , in order to provide for additional support, the plastic framing profiles 90 and 91 are ultrasonically spot welded to the legs 93 of the junction piece 92 . A double tip welding head is typically used creating spot welds 95 and 96 . Because the legs 93 only loosely fit within the profile, the ultrasonic welding process allows the plastic to flow in the gap between the junction piece legs 93 and the profile extrusions 90 and 91 creating an extra strong welded spot bond and reduced material flow on the exterior surface. Because of their complex shape, the junction pieces 92 are typically injection molded and have to be manufactured from essentially the same base thermoplastic resin material as the extruded profiles 90 and 91 . FIG. 11C shows a vertical cross section through the hollow framing profile 91 . The integral legs 93 of the junction piece 92 consist of a rigid flat bar 97 with a central positioning fin 98 . The profile extrusion incorporates a half circular indentation 99 and this allows the positioning fin 98 to be centrally located. FIG. 12 shows an alternative high volume production process for welding around an insulating glazing panel unit 25 . FIG. 12A shows a plan view of an insulating glazing panel unit 25 with U-Channel framing profiles 21 manually assembled around an insulating glazing panel unit 25 and where the profiles 21 are loosely interconnected by junction pieces 92 that incorporate integral legs 93 . FIG. 12B shows a plan view of the insulating glass/frame subassembly 100 where the profiles 21 are positioned around the insulating glass panel unit 25 and where the profiles are in part held in position by folding rubber spacer inserts (not shown). FIG. 12C shows a plan view of the insulating glass/frame subassembly 100 suspended below a gantry 101 and held in position by means of an adjustable clamping mechanisms 102 . FIG. 12D shows a plan view of four headed horizontal friction corner welder 103 where the insulating glass/frame subassembly 100 is transferred by the gantry 101 and dropped into position in the friction corner welder 103 . The removeable tabs 49 of the junction pieces 92 are located in the junction piece holding fixture 35 that are attached to the vibratory heads 33 . FIG. 12E shows a plan view of the insulating glass/frame subassembly 100 where the frame profiles 21 are clamped in position in moveable framing fixtures 104 and where the subassembly 100 is squared prior to friction corner welding the four corners 29 . After the welding process, the removable tabs 49 are automatically cut-off and the framing fixture clamps 104 are released. The assembled sash frame window 20 is then moved by the gantry 101 to the next window production operation. Because with this high volume production process, the framing profiles are not manually placed in the profile fixtures, weld cycle time is substantially reduced to less than fifteen seconds per window unit and this results in a production output of two thousand windows per eight hour shift. It should be noted that although a high volume sash frame production method is described in FIG. 12 , it can be appreciated by those skilled-in-the-art that the same production methods and apparatus can also be used to manufacture separate window frame assemblies. FIG. 13 shows a bottom cross-section detail of a U-channel sash window profile 21 featuring flexible fin spacers 105 and glazing-bulb seal 106 . U-shaped channel profiles 21 are assembled around the insulating glass panel unit 25 . The panel unit 25 is then inserted into the channel frame profile 21 . The double set of flexible fin spacers 105 that are integrally formed with the framing profile 21 are compressed downwards and hold the insulating glass unit 25 in position. Typically, the flexible fins 105 are made from flexible PVC plastic material and are extruded simultaneously with the PVC framing profiles. The dual seal insulating glass panel unit 25 is supported on a rubber support pad 107 that is positioned centrally in the U-shaped framing profile 21 . The support pad 107 incorporates an opening 108 to allow for water drainage from the glazing cavity 69 . The flexible glazing bulb seal 106 that is also integrally formed with the framing profile 21 prevents rain water run-off from entering the glazing cavity 39 . The use of integrally formed flexible fin spacers and bulb seals does not provide for the same structural performance as the twin sealant bead assembly previously described in FIG. 5 . However for smaller residential windows the use of integrally formed spacers provides for adequate structural performance and with the added advantage of lower equipment, material and labor costs.
A framed panel and related method of manufacture are disclosed. A framed panel unit includes a panel along the edge of which thermoplastic frame members are disposed. The frame members have first and second opposed side walls which define a channel for receiving the edge of the panel. The channel of each frame member has spacers between the panel and each side wall for spacing the panel from the side walls. Prior to welding together the ends of the frame members, the spacers retain the frame members on the panel. The panel may include multiple opposed sheet members with a spacer between the sheet members spacing them apart, and a reactive thermoplastic sealant material bonding the sheets to the frame members. An associated method of forming a named panel, frame members for a panel, and a spacer component for use in mounting a panel within a channel of a frame member are also disclosed.
1
FIELD OF THE INVENTION The present invention relates generally to container placement, and more specifically to the alignment and anchoring of safe deposit box nests. BACKGROUND OF THE INVENTION Almost every bank provides, for a rental fee, the use of safe deposit boxes wherein patrons may safely store valuables. In order to provide the bank a degree of flexibility in the configuration of individual safe deposit boxes, it has become customary to group individual safe deposit boxes in modular units, called "nests", which are stacked side-by-side and atop one another from floor to ceiling in the bank vault. A safe deposit box nest generally assumes the form of a steel or aluminum enclosure having a plurality of compartments, each of which has a double locking door. Each compartment contains an insert container in which the safe deposit box renter keeps valuables. The nests are configured to have a convenient size and weight. A horizontal depth of 24 inches is standard, with a width of 355/8 inches and a height of 17 inches being typical. While there is variation in the construction details of safe deposit box nests, a common construction utilizes 1/4-inch thick mild steel for the top, bottom, rear wall, and side walls and 1/2-inch thick mild steel for the door. While some nests are characterized by a flush bottom surface, some of the newer ones achieve certain economies by constructing the nest of relatively thicker material (e.g., 1/4-inch) in a band near its front and relatively thinner material (e.g., 1/8-inch) elsewhere. This requires spaced square shims at the rear corners of the bottom surface in order to level the nest. A typical weight for an empty nest is in the range of 250 to 700 pounds. Certain geographic locations are prone to earthquakes, and there have been devised methods of securing the nests to avoid the possibly catastrophic consequences of a falling nest. The need for such methods is especially great for the newer nests described above, since the area of contact between an upper and lower nest of that type is limited to the area of the band and shims (about 15% of the total horizontal area). One solution is to anchor the nests to the walls of the vault. However, the nests may then become part of the building property which is often undesirable from the bank's point of view. It is also known to bolt an overlying nest to an underlying nest at the corresponding adjacent corners. However, such a system of securing the nests has the disadvantage that access to the inside of the nest is required. It can be appreciated that it is not always easy, or even possible, to contact the renter of the box in order to gain such access. This problem may be somewhat alleviated by making the bolts of sufficiently small cross section that they are sheared when the nests are pried apart. It is still necessary, however, to gain access for reinstallation of the bolts. Moreover, any system (such as this) that entails a physical penetration of the nests may be undesirable for security reasons. SUMMARY OF THE INVENTION The present invention provides a surprisingly simple and effective system that prevents stacked safe deposit box nests from shifting horizontally relative to one another. The system does not require access to the inside of the nest for installation or removal, is self-actuating, and does not hinder in any way the separation of stacked nests when such separation is desired. In its broadest form, the present invention utilizes registered pluralities of retainer brackets mounted along the upper and lower edges of the rear wall of the nest. The retainer brackets are configured with a central portion that is spaced away from the nest wall to define a vertically opening passageway. The retainer brackets along the lower edge of an overlying nest may then be aligned with the retainer brackets along the upper edge of an underlying nest by bringing the two nests into precise registration. A locking member is then passed through each aligned pair of retainer brackets. The locking member is preferably in the form of a tab formed of sheet material, being sized for a sliding fit into the passageway. The tab is formed with a flange to define the maximum downward movement. When fully engaged, the tab extends sufficiently below the line of contact between the nests to provide the required degree of horizontal stabilization. The nests are constrained against sideways and fore-and-aft movement. It should be realized that the nests are normally positioned with their rear walls less than about an inch from the vault wall. Thus access to the rear of the installed nests is generally impossible. However, the present invention operates without requiring access to the rear. Installation of an overlying nest over an underlying nest may be effected according to the following procedure. The overlying nest is placed over the underlying one so that the side walls of both are in coplanar relationship, but is not pushed all the way back. The tabs are placed in the lower retainer brackets of the overlying nest, but do not fully seat themselves since they encounter the upper surface of the underlying nest. The overlying nest is then pushed back to a point where the rear walls of the two nests are coplanar, at which time the tabs drop gravitationally so that the lower portions of the tabs engage the upper retainer brackets of the underlying nest, thus effecting a positive locking. Unlocking of a registered engaged pair of nests is carried out in the context of a normal procedure wherein a steel wedge is driven between the nests from the front, and a steel roller inserted into the clearance at a point about halfway back. Once the wedge is removed, the front of the nest is easily lowered with the roller acting as a fulcrum. The rear of the nest may be raised by a distance determined by the roller diameter and location. As the rear of the overlying nest moves up, the tabs are pulled out of the brackets on the underlying nest. The tabs are sized so that their lower edges clear the upper surface of the underlying nest as the overlying nest pivots about the roller. The overlying nest may then be rolled toward the front for removal and relocation. The specific tab dimensions will typically depend on the roller diameter. It has been found that a 1/2-inch downward extension of the fully seated tab below the lower surface of the overlying nest works well with the 1/2-inch diameter rollers commonly used. This provides sufficient horizontal stabilization while allowing separation of the nests as outlined above. The present invention has the advantage of avoiding connection to the vault walls. Thus the nests do not become part of the building property. The present invention has the additional important advantage that it is applicable to virtually any type of safe deposit box nest. As such, existing arrays of nests may be retrofitted to take advantage of the present invention. Penetration of the nests is not required; thus security is left inviolate. For a further understanding of the nature and advantages of the present invention, reference should be made to the remaining portions of the specification and the appended drawings. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an isometric view illustrating the safe deposit box nest anchoring system according to the present invention; FIG. 2 is a detailed isometric view of the locking mechanism according to the present invention; and FIGS. 3A-C are schematic side elevational views illustrating a preferred procedure for separating and removing the nests. DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is an isometric view illustrating the installation and locking together of a plurality of safe deposit box nests 10a, 10b, and 10c in a bank vault. Nests 10a-c are stacked in overlying registration atop a base 12 which is anchored to the floor of the vault. Nests 10a-c are metal enclosures having respective rear walls 15a-c, side walls 17a-c and 18a-c, top surfaces 20a-c, and bottom surfaces 22a-c. In an illustrative context, nests 10a-c are constructed from 1/4-inch thick mild steel. Each nest encloses a plurality of compartments, each of which has a double locking door (not shown) at the front of the nest. Although dimensions vary from one banking institution to another, a horizontal depth of 24 inches is standard, with a width of 355/8 inches and a height of 17 inches (as used by at least one banking institution), being considered representative. Base 12 has a rear surface 25. In the present context, the significance of the designation rear is that rear walls 15a-c and rear surface 25 are located within about one inch of the vault's concrete wall. As can be seen in FIG. 1, nests 10b, 10a and base 12 are maintained in precise overlying registration by a bracket and tab arrangement to be described below. Nests 10a-c carry respective first lower retainer brackets 30a-c and respective second lower retainer brackets 32a-c mounted at a predetermined spacing proximate the respective lower edges of rear walls 15a-c. Additionally, nests 10a-c carry respective first upper retainer brackets 35a-c and respective second upper retainer brackets 37a-c mounted at the same predetermined spacing proximate the respective upper edges of the rear walls 15a-c. Base 12 carries first and second retainer brackets 40 and 42 mounted at the same predetermined spacing proximate the upper edge of rear surface 25. First lower retainer brackets 30a-c have associated therewith respective securing tabs 45a-c while second lower retainer brackets 32a-c have associated therewith respective second securing tabs 47a-c. The detailed configuration and operation of the retainer brackets and securing tabs may be understood with additional reference to FIG. 2 which is an enlarged isometric view showing the cooperation of retainer brackets 35a and 30b and securing tab 45b. Each retainer bracket is of stepped construction and includes a center portion 50 and paired flanking side portions 52. Side portions 52 are mounted directly to the rear walls and support center portion 50 at a location spaced apart from the wall. The retainer brackets are preferably made of steel, with side portions 52 being welded to the wall. In alternate, equally suitable embodiments, side portions 52 may be bolted (tapped holes in the rear wall) or epoxied to the rear wall. With nest 10b situated atop nest 10a in precise overlying registration, lower retainer brackets 30b and 32b on nest 10b are precisely registered with upper retainer brackets 35a and 37a on nest 10a. As can be seen in FIG. 2, the registration of retainer brackets 35a and 30b defines a vertically extending passageway 60. In the preferred embodiment, tab 45b (as well as the other securing tabs) includes a vertical planar portion 62 and a horizontal flange portion 65. Planar portion 62 is configured to provide a free sliding fit into passageway 60 while flange 65 limits the downward movement of the tab as it slides downwardly due to its own weight. The precise dimensions of the retainer brackets and securing tabs are not critical, although, as will be seen below, the preferred removal procedure implies certain dimensional constraints on the system. For definiteness, a preferred set of dimensions will be set forth, it being understood that wide variation in most dimensions is possible. Retainer bracket 30b is preferably formed from 14 gauge (0.0747 inch) thick steel and is approximately one inch high and 33/4 inches wide, with center portion 50 being sized to define a width of approximately 15/8 inches for passageway 60. Securing tab 45b may also be formed from 14 gauge steel, with planar portion 62 being approximately 2 inches high by 11/2 inches wide. Flange 65 extends approximately 1/2-inch from planar portion 62. Upper brackets 35a-c and 37a-c are mounted with their upper edges generally flush with the upper edge of the associated nest while lower retainer brackets 30a-c and 32a-c are mounted with their respective lower edges approximately 1/2-inch above the lower edge of the associated nest. Thus, as the tab occupies the passageway, there is approximately a 1/2-inch downward extension of the tab below the confronting surfaces of the nests. The significance of this 1/2-inch dimension will be described below in connection with the removal procedure. Installation of the locking system according to the present invention may be understood with reference to FIG. 1. In FIG. 1, nests 10a and 10b are already registered and locked while nest 10c is in the process of being positioned. The positioning procedure occurs as follows. Nest 10c is first placed atop nest 10b with side walls 17c and 18c of nest 10c in coplanar relationship with side walls 17b and 18b of nest 10b. However, nest 10c is not yet pushed all the way back to bring rear wall 15c into coplanarity with rear wall 15b. At any convenient time, such as prior to placing nest 10c atop nest 10b, tabs 45c and 47c are placed in respective lower retainer brackets 30c and 32c. With nest 10c atop nest 10b, tabs 45c and 47c do not fully seat within their respective retainer brackets, but rather are impeded from full downward travel by top surface 20b of underlying nest 10b. Nest 10c is then moved back. As soon as the rear walls of the two nests become coplanar, tabs 45c and 47c gravitationally drop fully downward into underlying upper retainer brackets 35b and 37b to effect a positive lock. FIGS. 3A-C are schematic side elevational views illustrating a preferred procedure for removing nest 10c, assumed to have been previously in position. With reference to FIG. 3A, the first step of the procedure involves driving a steel wedge 70 from the front in order to raise the front end of nest 10c. Nest 10c thus pivots about the lower edge of rear wall 15c. The amount of angular rotation is not so great as to cause bending of tabs 45c and 47c that align nests 10b and 10c. With reference to FIG. 3B, a steel roller 80 is then placed in the space between the nests approximately half way back, and wedge 70 removed. A 1/2-inch diameter roller is a convenient size. Then, as seen in FIG. 3C, the front of nest 10c is moved downwardly, so that the nest pivots about roller 80 which acts as a fulcrum. This rotation raises tabs 45c and 47c out of upper retainer brackets 35b and 37b of nest 10b. It has been found that a 1/2-inch extension of the tabs beneath the lower surface of the nest is sufficiently small that nest 10c may be pulled forward without interference from the tabs. At the same time, the 1/2-inch extension provides enough incursion into the underlying retainer brackets to provide adequate horizontal stabilization. The tabs are then removed at any convenient time when they are accessible. In summary it can be seen that the present invention provides a surprisingly simple and effective system for anchoring safe deposit box nests to prevent horizontal shifting of one nest relative to another. The system does not require access to the inside of the nest for locking or unlocking, nor does it require access to the rear walls of the nests when they are in position. Furthermore, the system may be applied to safe deposit box nests of virtually any design. Therefore, the retainer brackets and tabs can form the basis of a kit for retrofitting existing safe deposit box installations. While the above provides a full and complete disclosure of the preferred embodiments of the invention, various modifications, alternate constructions, and equivalents may be employed without departing from the true spirit and scope of the invention. For example, while each rear wall edge is disclosed as being provided with two retainer brackets, larger numbers of retainer brackets could also be used. Moreover, while steel is preferred, other materials may be used. Therefore, the above description and illustrations should not be construed as limiting the scope of the invention, which is defined by the appended claims.
A system that prevents stacked safe deposit box nests from shifting horizontally relative to one another utilizes registered pluralities of retainer brackets mounted along the upper and lower edges of the rear wall of the nest. The retainer brackets are configured with a central portion that is spaced away from the nest wall to define a vertically opening passageway. The retainer brackets along the lower edge of an overlying nest may then be aligned with the retainer brackets along the upper edge of an underlying nest by bringing the two nests into precise registration. A locking member is then passed through each aligned pair of retainer brackets.
4
CROSS REFERENCE TO RELATED APPLICATIONS This application is a continuation-in-part of Ser. No. 229,242, filed Jan. 28, 1981, now abandoned, a continuation-in-part of Ser. No. 386,870, filed June 10, 1982, now abandoned, a continuation-in-part of Ser. No. 463,762, filed Feb. 4, 1983, now abandoned, and a continuation-in-part of Ser. No. 577,477 filed Feb. 6, 1984, now abandoned. BACKGROUND OF THE INVENTION This invention relates to a method of preparing polycarbonates by the interfacial technique using organic solvents. It is known from U.S. Pat. No. 3,275,601, dated Sept. 27, 1966 that trialkylamines are effective to promote the polymerization of polycarbonate resins by an interfacial process. Other patents such as U.S. Pat. Nos. 3,185,664; 3,261,810; and 3,763,099 have indicated that other catalysts can be used such as phosphonium, arsonium, sulfonium, guanidine, and diamido compounds. SUMMARY OF THE INVENTION It now has been discovered that thermoplastic aromatic polycarbonates can be made by an improved process wherein a dihydric phenol is reacted with phosgene under interfacial process conditions in the presence of an organic solvent to generate a reaction mixture containing polycarbonate oligomers, adding 25 to 125 percent by volume based on the amount of the original solvent of additional organic solvent to the reaction mixture, adding a polymerization catalyst, stirring the reaction mixture for a period of time to complete the polymerization reaction, and recovering the polycarbonate. The amount of additional solvent added to the reaction mixture is in the range from 25 to 125 percent by volume and preferably 40 to 100 percent by volume of the original amount used. The process is useful to make thermoplastic polycarbonates having a reduced yellowness index and increased light transmittance and thus it gives polycarbonates having better optical properties than the known prior art processes. DETAILED DESCRIPTION The process of the invention is carried out at a temperature in the range from 0 to 40° ° C. by reacting 1.1 to 1.3 moles and preferably 1.2 to 1.3 moles of phosgene with one mole of a dihydric phenol or a mixture of dihydric phenols with an aqueous alkali metal hydroxide solution and an organic solvent for the polycarbonate oligomers which are formed. In general, the initial charge for the process is such that the organic solvent solution of the polycarbonate oligomers has about 5 to about 60 percent by weight of oligomers and preferrably in the range from about 15 to 50 percent by weight. After the polycarbonate oligomers are formed, the reaction mixture is diluted with about 25 to 125 volume percent of additional solvent based on the original amount used. An interfacial polymerization catalyst is then added in an effective amount generally ranging from 0.05 to 5.0 weight percent based on the dihydric phenol used, the mixture is stirred for 5 to 60 minutes and preferably 10 to 30 minutes at a temperature of 10° to 40° C. and preferably 20° to 30° C., and the polycarbonate solution is recovered. When phenol is used as a chain stopper, it is desirable to add about 0 to 30% of the total effective amount of the polymerization catalyst before the phosgenation reaction, with the remainder or 70 to 100 percent being added for the polymerization reaction. If tertiary butyl phenol is used, it is desirable to add all the polymerization catalyst after the phosgenation reaction. The final polycarbonate resins can be recovered by pouring the polycarbonate solution into an excess of a non-solvent for the resin such as hexane, ethanol, or petroleum ether. The precipitated resin is then filtered and dried. The dihydric phenols employed in the practice of this invention are known dihydric phenols in which the sole reactive groups are the two phenolic hydroxyl groups. Some of these are represented by the general formula ##STR1## where A is a divalent hydrocarbon radical containing 1-15 carbon atoms, ##STR2## X is independently hydrogen, chlorine, bromine, fluorine, or a monovalent hydrocarbon radical such as an alkyl group of 1-4 carbons, an aryl group of 6-8 carbons such as phenyl, tolyl, xylyl, an oxyalkyl group of 1-4 carbons or an oxyaryl group of 6-8 carbons and n is 0 or 1. One group of suitable dihydric phenols are those illustrated below: 1,1-bis(4-hydroxyphenyl)-1-phenyl ethane 1,1-bis(4-hydroxyphenyl)-1,1-diphenyl methane 1,1-bis(4-hydroxyphenyl)cyclooctane 1,1-bis(4-hydroxyphenyl)cycloheptane 1,1-bis(4-hydroxyphenyl)cyclohexane 1,1-bis(4-hydroxyphenyl)cyclopentane 2,2-bis(3-propyl-4-hydroxyphenyl)decane 2,2-bis(3,5-dibromo-4-hydroxyphenyl)nonane 2,2-bis(3,5-isopropyl-4-hydrophenyl)nonane 2,2-bis(3,-ethyl-4-hydroxyphenyl)octane 4,4-bis(4-hydroxyphenyl)heptane 3,3-bis(3-methyl-4-hydroxyphenyl)hexane 3,3-bis(3,5-difluoro-4-hydroxyphenyl)butane 2,2-bis(3,5-difluoro-4-hydroxyphenyl)butane 2,2-bis(4-hydroxyphenyl)propane (Bis A) 1,1-bis(3-methyl-4-hydroxyphenyl)ethane 1,1-bis(4-hydroxyphenyl)methane. Another group of dihydric phenols useful in the practice of the present invention include the dihydroxyl diphenyl sulfoxides such as for example: bis(3,5-diisopropyl-4-hydroxyphenyl)sulfoxide is(3-methyl-5-ethyl-4-hydroxyphenyl)sulfoxide bis(3,5-dibromo-4-hydroxyphenyl)sulfoxide bis(3,5-dimethyl-4-hydroxyphenyl)sulfoxide bis(3-methyl-4-hydroxyphenyl)sulfoxide bis(4-hydroxyphenyl)sulfoxide. Another group of dihydric phenols which may be used in the practice of the invention includes the dihydroxaryl sulfones such as, for example: bis(3,5-diisopropyl-4-hydroxyphenyl)sulfone bis(3-methyl-5-ethyl-4-hydroxyphenyl)sulfone bis(3-chloro-4-hydroxyphenyl)sulfone bis(3,5-dibromo-4-hydroxyphenyl)sulfone bis(3,5-dimethyl-4-hydroxyphenyl)sulfone bis(3-methyl-4-hydroxyphenyl)sulfone bis(4-hydroxyphenyl)sulfone. Another group of dihydric phenols useful in the practice of the invention includes the dihydroxydiphenyls: 3,3',5,5'-tetrabromo-4,4'-dihydroxydiphenyl 3,3'-dichloro-4,4'-dihydroxydiphenyl 3,3'-diethyl-4,4'-dihydroxydiphenyl 3,3'-dimethyl-4,4'-dihydroxydiphenyl p,p'-dihydroxydiphenyl. Another group of dihydric phenols which may be used in the practice of the invention includes the dihydric phenol ethers: bis(3-chloro-5-methyl-4-hydroxyphenyl)ether bis(3,5-dibromo-4-hydroxyphenyl)ether bis(3,5-dichloro-4-hydroxyphenyl)ether bis(3-ethyl-4-hydroxyphenyl)ether bis(3-methyl-4-hydroxyphenyl)ether bis(4-hydroxyphenyl)ether. Examples of useful organic solvents that can be used herein are hydrocarbon solvents such as cyclohexane, benzene, toluene, and xylene. Examples of useful halogenated solvents are 1,1,2,2-tetrachloro ethane, methylene chloride, 1,2-dichloro ethylene, trichloromethane, and 1,1,2-trichloroethane. The interfacial polymerization catalysts used herein are well known and include for example the trialkylamines such as triethylamine, triamylamine, tributylamine, tripropylamine, and the like; the quaternary ammonium compounds such as tetramethyl ammonium hydroxide, octadecyl triethyl ammonium chloride, benzyl trimethyl ammonium chloride and the like. If desired, well known chain stoppers such as p-tertiarybutyl phenol and phenols can be added to the reaction mixture to control the molecular weight of the polycarbonate resins. Reducing agents such as alkali metal sulfides, dithionites and sufites can also be used to remove trace amounts of oxygen during the reaction. The following examples and controls are presented to illustrate but not limit the invention. CONTROL A Dilution after polycondensation with TEA (triethylamine) catalyst Into a mixture of 272.4 parts by weight of 4,4'-dihydroxy diphenyl-2,2-propane (bisphenol A), 145 parts by weight of sodium hydroxide, 1045 parts by weight of deionized water, 1330 parts by weight (1.0 liter) of methylene chloride and 5.55 parts by weight p-tertbutylphenol, 150 parts by weight of carbonyl chloride were added over a period of 0.5 hour with stirring and at a temperature of 25° C. This resulted in solution of bisphenol A polycarbonate oligomers in methylene chloride at a concentration of about 23 percent by weight in the organic phase Then, 0.946 parts by weight of triethylamine were added. Stirring was continued for fifteen minutes, the agitation was stopped, the aqueous layer removed, and 1.0 liter of additional methylene chloride was added. The resulting polymer solution containing about 11.5 percent by weight polymer was washed twice with 10% aqueous hydrochloric acid, twice with water and dried. After precipitation of the polymer with n-heptane, the optical properties of molded discs of the precipitated polymer were determined. Gel permeation chromotography (GPC) analysis gave the molecular weight data. CONTROL B Dilution before phosgenation with TEA catalyst Control A was repeated except that two liters of methylene chloride were charged to the reactor initially and no additional methylene chloride was added. This resulted in a concentration of polycarbonate polymer of about 11.5 percent by weight in the organic phase. EXAMPLE NO. 1 Dilution before polycondensation with TEA (triethylamine) catalyst Into a mixture of 272.4 parts by weight of 4,4'-dihydroxy diphenyl-2,2-propane (Bis A), 145 parts by weight of sodium hydroxide, 1045 parts by weight of deionized water, 1330 parts by weight (1.0 liter) of methylene chloride and 5.55 parts by weight p-tertbutylphenol, 150 parts by weight of carbonyl chloride were added over a period of 0.5 hour with stirring and at a temperature of 25° C. This resulted in a concentration of polycarbonate oligomers of about 23 percent by weight in the organic phase. One liter of additional methylene chloride was added to the oligomer solution. Then, 0.946 parts by weight of triethylamine were added. Stirring was continued for fifteen minutes, the agitation was stopped, and the aqueous layer was removed. The resulting polymer solution was washed twice with 10% aqueous hydrochloric acid, twice with water and dried. After precipitation of the polymer with n-heptane, the optical properties of molded discs of the precipitated polymer were determined. Gel permeation chromotography (GPC) analysis gave the molecular weight data. EXAMPLE NO. 2 Dilution before polycondensation with TEA Into a mixture of 272.4 parts by weight of 4,4'-dihydroxy diphenyl-2,2-propane (Bis A), 194 parts by weight of 50% aqueous sodium hydroxide, 900 parts by weight of deionized water, 1330 parts by weight (1.0 liter) of methylene chloride and 5.6 parts by weight p-tertbutylphenol, 151 parts by weight of carbonyl chloride were added incrementially over a period of 0.5 hour with stirring and at a temperature of 22° to 25° C. Near the end of the carbonyl chloride addition, 96 parts by weight of additional 50% aqueous sodium hydroxide were added. This resulted in an organic phase containing about 23 percent by weight of oligomers. 500 ml of additional methylene chloride was added to the oligomer solution to give an organic phase containing about 15.6 percent by weight of oligomers. Then, 0.946 parts by weight of triethylamine were added. Stirring was continued for fifteen minutes, the agitation was stopped, and the aqueous layer was removed. The resulting polymer solution was washed twice with 10% aqueous hydrochloric acid, twice with water and dried. After precipitation of the polymer with n-heptane, the optical properties of molded discs of the precipitated polymer were determined. Gel permeation chromotography (GPC) analysis gave the molecular weight data. CONTROL C Example 2 was repeated without the addition of methylene chloride before the polymerization step. EXAMPLE No. 3 A 3785 liter (1000 gallon) reactor was charged with 1088.6 kg (2400 pounds) of water; 1124.9 kg (2480 pounds) of methylene chloride; 317.5 kg (700 pounds) of bisphenol A; 4,53 kg (10 pounds) of 90% phenol, and 226.8 kg (500 pounds) of aqueous sodium hydroxide containing 50% by weight NAOH. The mixture was then cooled to a temperature in the range of 20°-25° C. In the reactor was then added in sequence, 92.9 kg (205 pounds) of phosgene; 115.6 kg (255 pounds) of 50% aqueous NaOH; 86.2 kg (190 pounds) of phosgene; and 493.1 kg (1087 pounds) of methylene chloride with constant stirring of the reactor. The organic phase contained about 32 percent by weight of oligomers. The contents of the above reactor were then transferred to a 7520 liter (2000 gallon) reactor and 1578.5 kg (3480 pounds) of methylene chloride, and 1063 grams of triethyl amine were added with stirring to give an organic phase containing about 11.2 percent by weight of polymer. After 15 minutes, 13.6 kg (30 pounds) phosgene was added to bring the pH in the reactor to 8.5. After 15 minutes of stirring, the stirrer was turned off and the aqueous phase was allowed to separate from the organic phase containing the polycarbonate. The polycarbonate resin was recovered in the manner set forth in Control A. Over a series of 22 runs, the recovered polymer had an average yellowness index of 2.4 (standard deviation of 0.6), a percent transmittence of 89.9 (standard deviation 1.0), and a weight average molecular weight of 33,200 (standard deviation 200). CONTROL D Dilution after polycondensation with 4-dimethylaminopyridine (DMAP) catalyst Control A was repeated except that 1.14 grams of 4-dimethylaminopyridine dissolved in 3.3 ml of methylene chloride was used in place of the triethylamine to catalyze the polymerization. CONTROL E Dilution after polycondensation The procedure of Control D was repeated. EXAMPLE NO. 4 Dilution before polycondensation with DMAP catalyst Example No. 1 was repeated except that 1.14 grams of 4-dimethylaminopyridine dissolved in 4 ml of methylene chloride was used in place of the triethylamine to catalyze the polymerization. The color, clarity and the molecular weight of the examples and the controls are set forth in Table I. TABLE I______________________________________ yellow- % trans- molec- % Dilu- ness mit- ular tionSample Catalyst Index.sup.(1) tance.sup.(2) Weight.sup.(3) B.P..sup.(4)______________________________________Control A TEA 3.9 89.1 33,900Control B TEA 3.6 89.1 35,000Ex. #1 TEA 2.6 90.4 31,500 100Control C TEA 2.6 89.9 34,300Ex. #2 TEA 2.2 90.7 32,300 50Ex. #3 TEA 2.4 89.9 33,200 100Control D DMAP 2.8 88.5 33,200Control E DMAP 3.2 88.9 31,300Ex. #4 DMAP 1.9 89.5 39,200 100______________________________________ .sup.(1) determined by ASTM D 1925. .sup.(2) determined by ASTM D 1003. .sup.(3) determined by gel permeation chromatography. .sup.(4) B.P. = before polycondensation. The data in Table I shows that if the reaction mixture is diluted after the phosgenation step and before the polycondensation step there is a 33.3% and 27.7% reduction in yellowness index when one compares Example 1 with Controls A and B respectively. In the same manner, there is a 32.1% and 40.6% reduction when one compares Example 4 with Controls D and E respectively. Also there is a desirable increase in the percent transmittance of Example 1 and 2 over the controls. Example 3 shows a 38.5% and a 33.3% reduction in the yellowness index compared to Controls A and B. Example 2 shows a 15.3% reduction compared to Control C.
An interfacial process for the preparation of polycarbonates having improved optical properties is disclosed wherein dihydric phenols are reacted with phosgene in the presence of an aqueous alkali solution and an organic solvent. After the polycarbonate oligomers are formed, the reaction mixture is diluted with additional solvent (25 to 125 volume percent). A polymerization catalyst such as triethylamine is then added to generate high molecular polycarbonates and the resins are then recovered.
2
BACKGROUND OF THE INVENTION There has been a serious problem, particularly from the standpoint of arthritics and older persons or persons that have knuckles that are relatively larger than the phalanx or digital portions of their hands that are to receive and carry a ring in a displaying position. If the ring is provided with a size enabling an easy movement over an enlarged knuckle, then it has a sloppy or flip-flop positioning on the phalanx portion such as to create considerable annoyance to the wearer and to present a problem from the standpoint of maintaining the setting in a firm, front viewing position. Heretofore, an attempt has been made to solve this problem by using an enlarged ring size and then after it has been positioned on the phalanx, wrapping it with tape or thread to thus reduce its size to a suitable fit. However, this is unsightly, provides difficulty in effecting wrapping and requires frequent replacement. Jewelers have endeavored to solve the problem by cutting through the back shank of the ring somewhat centrally to provide a ring with some enlarging flexibility for slide-on mounting on the finger of the wearer. The opposed cut end portions are provided with a sliding clasp for closing and latching the spacing when the ring reaches its final position on the phalanx. Such a form of catch or slide fastening results in a ridge or projection that is uncomfortable to the wearer. Also in many cases, the ring shank is not sufficiently flexible for the purpose intended. Providing a ring shank of wound flexible material is unsanitary, results in a shortened life of the shank portion, and has an objectionable feel to the wearer. SUMMARY OF THE INVENTION I have been able to primarily meet the problem involved by making use of a ring of a sufficient size to easily slide over the enlarged knuckle and then, in accordance with the invention, provide a semi-circular shaped bridge that can be thereafter moved into a secure, inside position around and within the back and side portions of the ring so as to reduce its diameter to a desired size for the finger phalanx. I was presented with the problem of how to construct and utilize such a bridge in order that it can be easily inserted and removed when it is desired to remove or reposition the ring and, at the same time, maintain its bridging position within the circular ring shank portion of the ring during normal wearing conditions and without an objectionable "feel" to the wearer. A further important factor has been the need to provide a bridge that will be relatively inexpensive to produce and that can be provided in various sizes for ready adaptation to the wearer's requirements. Heretofore, the above described cut-out type of construction or adaptation of a ring required craftsman work that has been very expensive to the ring owner. In one embodiment of my invention I have provided a removable and in a second embodiment I have provided a hinged bridge which can be easily mounted by a jeweler on a conventional ring and which will be a more refined and stable type of mounting from the standpoint that the bridge is, itself, hingedly attached to the ring shank, but in such a manner as to avoid a localized ridge or offset that will be uncomfortable to the wearer's finger. The latter construction is also so devised as to provide a one piece ring-adaptor unit, and of a type that will not damage the ring shank, will be substantially invisible when the ring is being worn, and will be so constructed that it can be easily swung into a substantially locked wearing position after the ring has been slid over the enlarged knuckle onto the finger phalanx. BRIEF DESCRIPTION OF THE DRAWINGS In the drawings, FIG. 1 is a bottom plan view of a conventional ring showing a removable adaptor device or bridge element of the invention in finger wearing position therein; this view shows the construction as it will appear looking outwardly from the hand towards the end of the finger; FIG. 2 is a plan view of the ring with the adaptor bridge element removed; FIG. 3 is a top plan view of the adaptor element or bridge device when removed from the mounted position of FIG. 1 within a ring shank; FIG. 4 is a side view in elevation of the device or element of FIG. 3; FIG. 5 is a somewhat diagrammatic view illustrating how the ring shown in FIG. 2 is slid from the index portion of the finger over an enlarged knuckle onto the wearer's phalanx and thus into a receiving position for the bridge device or element; the bridge device in this view has the correct position for the final mounting to provide a composite assembly; FIG. 6 is a top plan view of a ring employed in a second or unitary type of embodiment of the invention in which the bridging device is hingedly mounted on the central location of the ring shank; FIG. 7 is a top plan view of the ring of FIG. 6 illustrating a first step in adapting it to receive and mount a hinge part of a bridge part thereon; FIG. 8 is a top plan view and FIG. 8A is a side view of a bridge part that is to be mounted between cut-off opposed ends of the shank of the ring shown in FIG. 7; FIG. 9 is a top plan view of the ring of FIG. 7 having the bridge part of FIG. 8 in a final mounted and secured position thereon; FIG. 10 is a side view in elevation of the composite ring construction of FIG. 8 showing by an arrow how the shank is closed to provide the desired finger-fitting relation on the phalanx of the wearer; this closing action is from the back underside portion or the palm side of the finger; FIG. 11 is a sectional view on the scale of and taken along the line VIII--VIII of FIG. 9; And, FIG. 12 is a view similar to FIG. 5 but which illustrates the mounting of the composite ring of FIG. 9 on the finger of the wearer. DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring particularly to FIGS. 1 to 5, inclusive, a ring 10 of conventional construction is shown having a circular banding or shank portion 11 and a front mounting crest portion 11b. Conventionally, stone settings such as 12, may be inserted in the crown portion 11b which thus represents the portion of the ring which is to face outwardlly of the finger of the wearer for comfort and for display. As indicated a lady's ring 10 may have a groove portion 10a which extends from opposite central side portions thereof along the crest portion 11b. This is not essential, however, to the employment of a bridge device such as illustrated in FIGS. 3 and 4. As shown in FIG. 5, the ring 10 is, in accordance with the invention, provided with an enlarged size selected on the basis of the size of the wearer's enlarged knuckle B. It may be conventionally of about two sizes larger than required for a snug, comfortable wearing fit on a phalanx, terminating or hand connected portion C of a finger. The ring 10 is slid, as shown by the arrow of FIG. 5, from the index portion A over the knuckle B and into a final mounted relation within a half moon shaped adaptor element or bridge device 15 of the invention. With particular reference to FIGS. 3, 4 and 5, the adaptor device 15 is shown provided with a sloped, smoothly rounded main body 15a. The body 15a on its inside is substantially semi-circular in shape so as to form a continuation of the circular shank 11 ring 10 with which it is to be used as an inside mounting within a half portion thereof. Its smoothly sloped, rounded body 15a terminates on one side pair of slightly projecting, opposite side flanges 15b, and has a centrally located, back-positioned entry slot 15d which is shown in alignment with a projecting, knurled push tab 16 on the opposite side of its body. As indicated in FIG. 5, when the ring 10 and its shank 11 have been moved to a final wearing position, the flange 15b of the bridge 15 will engage against the inside side face of the ring band in smooth abutment therewith, while the smoothly curved side 15a and the push removal tab 16 face outwardly of the ring band and towards the tip or front end A of the finger on which the ring is mounted. The arrangement is such that normal wearing of the composite assembly on the finger phalanx C will tend to retain the bridge 15 in its inside, size-reducing position within the back half of the ring shank or its band 11 to provide a comfortable and a desired snug fit of reduced diameter for the particular size of the finger phalanx C. This half moon insert device or element 15 can be made of any suitable material, such as metal or plastic (resin) material, and a jeweler can provide sizes from, for example, 2 through 16, to fit any size ring and provide any size of fitting as required in view of the wearer's size of enlarged knuckle B and ring-receiving phalanx C. Thus, a very practical, inexpensive and highly satisfactory type of size adaptation is accomplished without in any way altering the construction of the ring. In the embodiment shown in FIGS. 9 to 11, inclusive, the circular ring body, band or shank 21 of the ring 20 also conventionally has a slight centrally located inner groove 21a and crown 22. In this embodiment, a bridge 25, preferably of metal of the same type as the ring 20, is provided with a 180° swingable hinge fit on a central back portion of the shank 21. As shown, the bridge 25 is provided with a slightly projecting hinge having a tongue portion 23 that has a bifurcated portion 24 pivotally mounted thereon by a pin 26 in such a manner that the bridge can only be swung downwardly-outwardly and backwardly when the hinge is mounted on the ring shank or body 21. See the arrow of FIG. 10. A pair of radially outwardly extending, oppositely positioned tabs or dimples 27 are secured to extend from the outer side arms of the bridge 25 for inside snap into the groove 21a to normally retain the bridge 25 when it is moved from an open or outside horizontal position of FIG. 9 to an inside swung position, as indicated by the arrows of FIGS. 10 and 12. The tabs 27 abut the inside of the ring shank 21 when the ring 20 is being carried on the phalanx C of the finger of the wearer (see FIG. 12). The construction is such that the bridge 25 cannot be moved upwardly through the ring 20 on its hinge, but can only be swung 180° from an outward horizontal position downwardly to a vertical position and then to a front, ring-inserted, horizontal, finger mounting position on the finger phalanx C (see FIG. 9). An upper face of the bridge part 25 has a push tab or knurled portion 28 in a central or middle location thereon and in an aligned relation with respect to the hinge. The tab 28 facilitates a "down" push on the semi-circular bridge 25 to open it with respect to the ring 20. A single and inexpensive procedure is involved in making the composite structure of FIGS. 9 and 10. First, the purchaser selects the style and setting of the ring 20 from the jeweler's display. The jeweler then cuts out a small piece of the shank 21, as shown in FIG. 7, to provide a slight mounting space a between exposed, opposed ends of the shank. The jeweler measures the size of the knuckle B of the finger on which the ring is to be worn and provides a ring shank of an appropriate size for sliding thereover. This may, for example, be one or two sizes larger than the desired size for a suitable snug or wearing fit on the finger phalanx C. The jeweler then selects a size of bridge part 25 from his sized stock which, when mounted on the ring 20, will provide a desired fit on the purchaser's finger phalanx C. He follows this by inserting the projecting hinge of the selected bridge 25 in the space a (see FIG. 7) and welding, soldering, brazing or cementing it securely in place between opposed ends of the ring shank 21. This provides a composite structure that does not detract from the appearance of the ring and when worn is substantially invisible to others viewing the ring. The bridge mounting is such that it will be retained within the circular ring shank as a substantially unitary, hidden, size-reducing, semi-circular back, inner part thereof. The invention also enables the jeweler to easily adapt a customer's own ring by cutting and enlarging its shank sufficiently to easily slide over the customer's finger knuckle, and then selecting the mounting a suitable semi-circular bridge of the invention to reduce the ring wearing diameter to an appropriate size.
This invention relates to a finger ring adaptor device or bridge that will permit use by the wearer of a ring of a sufficient size to be easily slid over an enlarged knuckle or joint and to be thereafter reduced to a desired snug fit on the phalanx or digital portion of the finger.
0
BACKGROUND OF THE INVENTION 1. Field of the Invention The invention relates to heating mechanisms for process chambers, and particularly, to heating mechanisms for chemical vapor deposition chambers. 2. Description of Related Art Chemical vapor deposition (CVD) is a process for depositing various types of films on substrates and is used extensively in the manufacture of semiconductor-based integrated circuits such as, for example, the processing of semiconductor wafers (wafers) to form individual integrated circuit devices. In typical CVD processing, a wafer or wafers are placed in a deposition or reaction chamber and reactant gasses are introduced into the chamber that are decomposed and reacted at a heated surface to form a thin film on the wafer or wafers. A CVD reactor vessel adds coatings to wafers using a multi-zone resistive heater (heater) to react the coating chemistry once applied to a wafer surface. The heater includes at least two resistive heating rods disposed within a tube to contact a spiral heater coil (coil) embedded within a heater disk (disk). The distinct heating rods are not equadistantly centered about the tube centerline nor the coil. Instead they are offset, the result being that areas of the heating disk can have a wide range of temperatures provided by varying the electrical power applied to the individual heating rods. A specially designed surface (susceptor) exists on one side of the heating disk upon which is supported the wafer. The wafer is heated conductively by heat transferred from the heating coil to the susceptor. Upon completion of the deposition of the film onto the wafer, the process gasses are removed, the reaction chamber purged with cleaning chemicals and inert gasses, and the wafer removed. Initially at assembly, an interior volume of the heater assembly is exposed to atmosphere. Once the heater is assembled, atmosphere will remain contained within. Oxygen in the atmosphere that is contained within the heater assembly will attack the heater components at temperatures above 700° C. As a result, the mechanical strength of the heater components will degrade with use and the heater components will have to be replaced at a cost in parts, labor, and down time for the reactor vessel. SUMMARY OF THE INVENTION A wafer processing method, comprising processing a wafer in a reaction chamber comprising a heater having an interior space; heating the reaction chamber with the heater, purging an inert gas into the heater interior space, and venting the inert gas. BRIEF DESERTION OF THE DRAWINGS FIG. 1 is an illustration of a CVD reactor assembly; FIG. 2 is an illustration of a portion of the CVD reactor assembly; FIG. 3 is an illustration of a portion of the CVD reactor assembly; FIG. 4 is an illustration of a portion of the CVD reactor assembly; FIG. 5 is a an illustration of a resistive heater assembly; FIG. 6 is an illustration of a spiral coil; FIG. 7 is an illustration of the resistive heater assembly with purge; FIG. 8 is an illustration of the resistive heater assembly with vacuum. DETAILED DESCRIPTION OF THE INVENTION The invention generally relates to a method and an apparatus for removing reactive gasses from the interior of a multi resistive heater (heater) used in a semiconductor wafer processing reaction chamber. Wafer processing requires corrosive chemistry to be applied at high temperatures and the heater components that must withstand this environment are currently manufactured from a ceramic material, aluminum nitride (AlN). While the heater interior is subject to the same heating conditions as the reaction chamber, it is sealed and not exposed to the processing gasses during operation of the reaction chamber. The heater interior is assembled and disassembled in atmosphere and therefore contains atmospheric gasses, in particular oxygen. At operating temperatures greater than 700° C., aluminum nitride when exposed to atmosphere, will react with the oxygen and the material strength of the AlN component will be reduced. As a result, the service life of the heater is reduced. The heater interior surfaces, made of aluminum nitride, that are exposed to atmosphere and processing heat during wafer processing include; the inside surfaces of a tube, a portion of a heater disk that is covered by the tube, and a set heating rod insulators. A method and apparatus for reducing or eliminating the oxygen from these inner heater surfaces (heater interior) is disclosed. In an embodiment, the method comprises a continual flow of an inert fluid through the interior of the heater to maintain an oxygen free environment. The inert fluid can be a liquid or a gas or combination of gasses that are non-reactive at the operating conditions of the intended use. In another embodiment, a vacuum is placed within the heater interior to ensure no oxygen is present. FIG. 1 is an illustration of a reactor vessel assembly (reactor) 100 that processes a film onto a semiconductor wafer. The reactor vessel assembly 100 is comprised of a chamber assembly 102 and a resistive heater assembly (heater) 104 for use in a chemical vapor deposition apparatus. Heater 104 is designed to move along an axis 105 relative to chamber assembly 102 . A chamber body 106 defines a reaction chamber 108 where the reaction between a process gas or gasses and the wafer takes place, e.g., a CVD reaction. Chamber body 106 is constructed, in an embodiment, of 6061-T6 aluminum and has passages 110 for water to flow through to cool chamber body 106 . Resident in reaction chamber 108 is resistive heater (heater) 104 that includes several heating elements (rods) 112 running the length of a heater tube (tube) 114 that are made of nickel. At the end of tube 114 is a heating disk (disk) 116 made of sintered AlN. Sintered within disk 116 is a spiral heating element (coil) 118 made of molybdenum. Rods 112 and coil 118 are joined with a brazing and are electrically conductive therein. Rods 112 are thermally insulated with AlN ceramic sleeves 120 . Coil 118 provides most of the electrical resistance and therefore most of reaction chamber 108 heating. At the end of heating disk 116 is a recess called a susceptor 122 within that is placed a wafer (not shown). In an embodiment, susceptor 122 has a surface area sufficient to support a 200 millimeter diameter semiconductor wafer (200 mm wafer) while in another embodiment, susceptor 122 has a surface area sufficient to support a 300 millimeter diameter semiconductor wafer (300 mm wafer). Referring still to FIG. 1, heater 104 is retracted along an axis 105 and the wafer (not shown) is placed in reaction chamber 108 on susceptor 122 through an entry port 134 in a side portion of chamber body 106 . To accommodate the wafer for processing, heater 104 is retracted until a surface of susceptor 122 is below entry port 134 . A transfer blade (FIG. 2 below) places the wafer (not shown) into chamber body 106 within susceptor 122 . Once loaded, entry port 134 is sealed and heater 104 is advanced in a direction toward faceplate 130 by lifter assembly 136 . At this point, process gasses controlled by a gas panel (not shown) flow into chamber 108 through port 124 , through blocker plate 128 , through faceplate 130 , and typically react or are deposited onto the wafer (not shown) to form a film (not shown). Using a pressure controlled system (not shown), the pressure in chamber 108 is established and maintained by a pressure regulator or regulators (not shown) coupled to chamber 108 . FIG. 2 is an embodiment of a simplified processing area around wafer 132 with many of the reactor 100 (FIG. 1) components removed for clarity. Process gasses 154 enter reaction chamber 108 through an opening 124 in a top surface of a chamber lid 126 of chamber body 106 . The process gases first pass through a blocker plate 128 . Blocker plate 128 is perforated with a set of holes (not shown) to radially distribute the process gas. The process gasses then pass through holes (not shown) of a second perforated plate known as a faceplate 130 . Faceplate 130 provides uniform distribution of the process gasses 154 onto wafer 132 . A pump (not shown) draws on a pumping plate 138 at a collection channel 140 . As a result, after impacting wafer 132 , process gases 154 pass through radial holes 156 in pumping plate 138 , are collected in an annular channel 140 , and are then directed out of reaction chamber 108 . Chamber 108 may then be purged 155 , for example, with an inert gas, such as nitrogen. In an embodiment, as shown in FIG. 3, after processing and purging, heater 104 is moved in a lower direction (away from a chamber lid 126 ) by a lifter assembly 136 lift pins 142 are positioned at the base of reaction chamber 108 . Lift pins 142 have one end positioned through holes in disk 116 to a contact lift plate 144 . As heater 104 moves in a lower direction along axis 105 , through the action of a lifter assembly 136 , lift pins 142 remain stationary and ultimately extend above the top surface of disk 116 to separate processed wafer 132 from the surface of susceptor 122 . In an embodiment, as shown in FIG. 4, once processed, wafer 132 is separated from the surface of susceptor 122 by transfer blade 166 of a robotic mechanism (not shown) that is inserted through opening 134 to remove wafer 132 . The steps described above are reversed to bring wafer 132 into a process position. In a high temperature operation such as low pressure CVD (LPCVD) processing of Si 3 N 4 or polysilicon, the reaction temperature inside the reaction chamber 108 can be as high as 750° C. or more. Accordingly, the exposed components in reaction chamber 108 must be compatible with such high temperature processing. Such component materials should also be compatible with the process gasses and other chemicals, such as the cleaning chemicals that may be introduced into reaction chamber 108 . An exploded view of a dual-zone heater (heater) is shown in an embodiment as illustrated in FIG. 5 . In this embodiment, tube 214 , disk 216 , and heater rod insulators 220 are comprised of sintered and machined aluminum nitride (AlN). Heater disk 216 is sintered having heating coil 218 contained within. Heating coil 218 is bonded to tube 214 through diffusion bonding or brazing as such coupling will similarly withstand the environment of reaction chamber 108 (FIG. 1 ). Heater assembly 204 includes heater disk 216 having surface 258 with susceptor (not shown) to support a wafer (not shown) and opposite surface 260 to couple to tube 214 . Located within tube 214 is two pair of heating rods 212 equidistantly disposed about a common centerline 246 . Each heating element 212 is housed in ceramic sleeve (AlN) 220 . Each heating rod 212 is made of a material having thermal expansion properties similar to the material of tube 114 . In this embodiment, heating rods 212 are made of nickel (Ni), the heating rods 212 having a thermal expansion coefficient similar to aluminum nitride. The heating rods 212 pass through an end cap 250 and are attached to electrical connections (not shown) that enter the end cap 250 from the opposite side. A thermocouple 248 can be positioned within the tube 214 of the heater assembly 204 with the electrical connections placed at the end cap 250 . An end of the thermocouple 240 can contact the heater disk 216 to provide a temperature profile of the heater disk 216 during operation. However, in an embodiment as illustrated in FIG. 6, heating rods 212 are not centered around the common centerline 217 of heater disk 216 , heater coil 218 (dashed line), and tube 214 . This non-centering of heating rods 212 to centerline 217 used by the other components, along with the individual electrical control to each heating rod 212 , provides the full temperature range required in CVD processing. Referring now to an embodiment as illustrated in FIG. 7, atmospheric gasses are purged from the inside of dual-zone heater 304 . The purge may be accomplished with a constant flow of a fluid such as an inert gas at a flow rate of approximately 100 cubic centimeters per minute (ccm) through a connector base 355 , a connector adapter 350 and into tube 314 . For an embodiment, nitrogen may be used as the inert gas. The nitrogen gas pressure applied to the heater, along with the size of the inlet port 362 and vent port 364 should be such as to provide a desired flow rate through the heater 304 . In one embodiment, the flow of nitrogen gas could be at a rate to maintain a pressure of 30 pounds per square inch (psi) when purged into an inlet port 362 . The nitrogen can vent out of heater 304 at a vent port 364 . The nitrogen used may be refrigerated to a temperature. Refrigerated nitrogen can maintain the temperature below 700° C. within the heater and further reduce AlN material degradation as a result of any small amount of oxygen remaining within the heater interior 366 . One method to refrigerate the nitrogen is to mix nitrogen at ambient temperature with nitrogen vapor evaporating off liquid nitrogen The purge may be continuous in that it can be started prior to beginning the wafer process cycle to ensure that oxygen is removed from heater interior 366 before the wafer process cycle begins. In addition, the purge into the heater may be continuous regardless of wafer processing and may only be stopped for heater disassembly to repair or discard. In an embodiment, a connector assembly 370 connects to heater 304 at one end and provides a multitude of connections. Connector assembly 370 attaches to end cap 345 , to heater tube 314 , and to chamber body 106 (FIG. 1 ). Passing through connector assembly 370 is inlet port 362 , vent port 364 , electrical connections 372 for a thermocouple (not shown), and electrical connections for heater rods 312 . Connector assembly 370 includes a connector adapter 350 and a connector base 355 . Connector adapter 350 attaches electrical connections 372 to the ends of heater rods 312 . Attached to connector adapter 350 is connector base 355 that attaches to chamber body 106 (FIG. 1 ). Inlet port 362 passes through end cap 345 while venting past the end cap 345 may be accomplished with loose dimensional tolerancing. With this connector assembly 370 configuration, a single operation of attaching connector assembly 370 to heater 304 provides for all the electrical and fluid connections simultaneously. The heater 304 acts as a pressure vessel in that it has pressure integrity. This is accomplished by O-rings 375 placed between components: heater tube 314 , end cap 345 , connector assembly 370 , to reduce loss of inert gas into the reaction chamber 108 (FIG. 1 ). Alternatively in an embodiment, as illustrated in FIG. 8, heater interior volume 466 within heater 404 may be evacuated with vacuum to remove the resident atmosphere. Connector assembly 470 connects to heater 404 at one end and provides a multitude of connections 474 . Connector assembly 470 attaches to end cap 445 , to heater tube 414 , and to chamber body 106 (FIG. 1 ). Passing through connector assembly 470 is vacuum port 462 , vent port 464 , electrical connections 472 for a thermocouple (not shown), and electrical connections for heater rods 412 . Connector assembly 470 includes a connector adapter 450 and a connector base 455 . Connector adapter 450 attaches electrical connections 472 to the ends of heater rods 412 . Attached to connector adapter 450 is connector base 455 that attaches to chamber body 106 (FIG. 1 ). Vacuum port 462 passes through end cap 445 to gain access to heater interior volume 466 . Attached to vent port 464 may be a vacuum or pressure gauge 476 to monitor vacuum levels. With this connector assembly 470 configuration, a single operation of attaching connector assembly 470 to heater 404 provides for all the electrical and fluid connections simultaneously. Heater 404 acts as a pressure vessel in that it has pressure integrity. This is accomplished with O-rings 475 that are placed between components: heater tube 414 , end cap 445 , and connector assembly 470 , to block vacuum from pulling into the heater interior volume 466 any of the reaction chamber chemistry. When vacuum is applied to vacuum port 462 , the heater interior 466 is subjected to an approximate 5 torr vacuum. In this manner, a vacuum source is continuously applied to interior 466 of heater 404 . In addition to monitoring vacuum levels, vacuum gauge 476 may be used to leak check the vacuum integrity of heater interior 466 . The ability of heater 404 to hold sufficient vacuum may be confirmed by periodic leak checks that test heater 404 pressure integrity. The leak check may be performed by sealing off heater interior 466 from a vacuum source and monitoring a loss of vacuum over time for a rate of vacuum decay. An approximate vacuum decay rate in the range of 0-2.5 torr per five hours could be acceptable. It should be appreciated for the described embodiments that modifications and adjustments to the invention might be accomplished. For instance, for the embodiment providing a vacuum in the heater interior 466 , it may be determined that for some process temperatures (below 700° C.), the vacuum requirement in the first embodiment may be of a range such as 2.5-10 torr. It should be appreciated that for the embodiment performing a purge, that a variety of fluids may be used. In particular, any inert gas may be used in substitute for nitrogen such as halogen gases. The purge of inert gas through heater interior 466 may be accomplished at purge rates that vary from 100 ccm dependent on temperature of the inert gas going in and the desired temperature of the heater interior volume 466 . Purge pressures other than 30 psi may be applied to fine-tune the purge process. Along with varying the purge flow rate, the purge gas(es) may be cooled or refrigerated to control the temperature within the heater. In addition, instead of a purge port, dimensional tolerancing of the mating connector component could be specified to be a loose tolerance. Such loose tolerancing would provide spaces between components that may allow the purge gas to leak out between the components at a sufficient rate to eliminate the need for a vent port. It is also possible to purge continuously (non-stop) regardless of wafer processing to further insure that no atmosphere is present within the heater interior during operation. In another embodiment, an inert gas is purged through the heater until the atmosphere has been removed. At a point, both purge and vent sides are shut off or blocked and the inert gas to a selected pressure would remain standing or static within the pressure vessel. A pressure gauge could be used to confirm that no discernable pressure change had occurred in the heater interior. A discernable pressure loss is any loss that is not acceptable for the design, operation, and useful life of the heater. In another embodiment, vacuum may be applied to the heater interior volume until a particular vacuum level is reached and then the vacuum source may be shut off to the heater interior volume. A vacuum gauge that is in-line or attached to the vacuum system near or at the heater interior could monitor the vacuum level within the heater interior. This would allow for better notice of loss of vacuum integrity of the heater interior.
An apparatus for wafer processing that includes a wafer reaction chamber containing a heater within, the heater including an interior volume containing at least one heating element, a fluid inlet port, and a fluid vent port positioned to vent the fluid outside the wafer reaction chamber. Additionally, the interior volume has a seal that isolates it from the wafer reaction chamber.
2
BACKGROUND OF THE INVENTION [0001] The present invention relates to cardiology, and more specifically to methods and apparatus for determining alternans data of an electrocardiogram (“ECG”) signal. [0002] Alternans are a subtle beat-to-beat change in the repeating pattern of an ECG signal. Several studies have demonstrated a high correlation between an individual's susceptibility to ventricular arrhythmia and sudden cardiac death and the presence of a T-wave alternans (“TWA”) pattern of variation in the individual's ECG signal. [0003] While an ECG signal typically has an amplitude measured in millivolts, an alternans pattern of variation with an amplitude on the order of a microvolt may be clinically significant. Accordingly, an alternans pattern of variation is typically too small to be detected by visual inspection of the ECG signal in its typical recorded resolution. Instead, digital signal processing and quantification of the alternans pattern of variation is necessary. Such signal processing and quantification of the alternans pattern of variation is complicated by the presence of noise and time shift of the alternans pattern of variation to the alignment points of each beat, which can be caused by limitation of alignment accuracy and/or physiological variations in the measured ECG signal. Current signal processing techniques utilized to detect TWA patterns of variation in an ECG signal include spectral domain methods and time domain methods. BRIEF DESCRIPTION OF THE INVENTION [0004] In light of the above, a need exists for a technique for detecting TWA patterns of variation in an ECG signal that provides improved performance as a stand-alone technique and as an add-on to other techniques. Accordingly, one or more embodiments of the invention provide methods and apparatus for determining alternans data of an ECG signal. In some embodiments, the method can include determining at least one value representing at least one morphology feature of each beat of the ECG signal and generating a set of data points based on a total quantity of values and a total quantity of beats. The data points can each include a first value determined using a first mathematical function and a second value determined using a second mathematical function. The method can also include separating the data points into a first group of points and a second group of points and generating a feature map by plotting the first group of points and the second group of points in order to assess an alternans pattern of variation. BRIEF DESCRIPTION OF THE DRAWINGS [0005] FIG. 1 is a schematic diagram illustrating a cardiac monitoring system according to the invention. [0006] FIG. 2 illustrates an ECG signal. [0007] FIG. 3 is a flow chart illustrating one embodiment of a method of the invention. [0008] FIG. 4 illustrates a maximum morphology feature. [0009] FIG. 5 illustrates a minimum morphology feature. [0010] FIG. 6 illustrates an area morphology feature. [0011] FIG. 7 illustrates another area morphology feature. [0012] FIG. 8 illustrates a further area morphology feature. [0013] FIG. 9 illustrates still another area morphology feature. [0014] FIG. 10 illustrates a plurality of beats, each beat being divided into a plurality of portions. [0015] FIG. 11 illustrates a window establishing a size of one of the plurality of portions of FIG. 10 . [0016] FIG. 12 illustrates a feature matrix. [0017] FIG. 13 illustrates a decomposition of the feature matrix of FIG. 12 as generated by a principal component analysis. [0018] FIG. 14 illustrates a plot of values of data corresponding to values representative of a morphology feature. [0019] FIG. 15 illustrates a determination of difference features using the values plotted in FIG. 14 . [0020] FIG. 16 illustrates another determination of difference features using the values plotted in FIG. 14 . [0021] FIG. 17 illustrates a further determination of a difference feature using the values plotted in FIG. 14 . [0022] FIG. 18 illustrates a feature map of first and second groups of points generated using values of a vector of data. [0023] FIG. 19 illustrates a feature map generated using values of a vector of data generated by performing a principal component analysis on a feature matrix including the vector of data utilized to generate the feature map of FIG. 18 . [0024] FIG. 20 illustrates a feature map of first and second groups of points generated using a first mathematical function and a second mathematical function. [0025] FIG. 21 illustrates a feature map of third and fourth groups of points generated using a third mathematical function and a fourth mathematical function. [0026] FIG. 22 illustrates a feature map of fifth and sixth groups of points generated using a fifth mathematical function and the sixth mathematical function. [0027] FIG. 23 illustrates a distance between a first center point of a first group of points and a second center point of a second group of points each plotted to form a feature map. [0028] FIG. 24 illustrates a spectral graph generated using values of a vector of data. [0029] FIG. 25 illustrates a spectral graph generated using values of a vector of data generated by performing a principal component analysis on a feature matrix including the vector of data utilized to generate the spectral graph of FIG. 24 . DETAILED DESCRIPTION [0030] Before any embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limited. The use of “including,” “comprising” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. The terms “mounted,” “connected” and “coupled” are used broadly and encompass both direct and indirect mounting, connecting and coupling. Further, “connected” and “coupled” are not restricted to physical or mechanical connections or couplings, and can include electrical connections or couplings, whether direct or indirect. [0031] In addition, it should be understood that embodiments of the invention include both hardware and electronic components or modules that, for purposes of discussion, may be illustrated and described as if the majority of the components were implemented solely in hardware. However, one of ordinary skill in the art, and based on a reading of this detailed description, would recognize that, in at least one embodiment, the electronic based aspects of the invention may be implemented in software. As such, it should be noted that a plurality of hardware and software based devices, as well as a plurality of different structural components may be utilized to implement the invention. Furthermore, and as described in subsequent paragraphs, the specific mechanical configurations illustrated in the drawings are intended to exemplify embodiments of the invention and that other alternative mechanical configurations are possible. [0032] FIG. 1 illustrates a cardiac monitoring system 10 according to some embodiments of the invention. The cardiac monitoring system 10 can acquire ECG data, can process the acquired ECG data to determine alternans data, and can output the alternans data to a suitable output device (e.g., a display, a printer, and the like). As used herein and in the appended claims, the term “alternans data” includes TWA data, or any other type of alternans data that is capable of being determined using one or more embodiments of the invention. [0033] The cardiac monitoring system 10 can acquire ECG data using a data acquisition module. It should be understood that ECG data can be acquired from other sources (e.g., from storage in a memory device or a hospital information system). The data acquisition module can be coupled to a patient by an array of sensors or transducers which may include, for example, electrodes coupled to the patient for obtaining an ECG signal. In the illustrated embodiment, the electrodes can include a right arm electrode RA; a left arm electrode LA; chest electrodes V 1 , V 2 , V 3 , V 4 , V 5 and V 6 ; a right leg electrode RL; and a left electrode leg LL for acquiring a standard twelve-lead, ten-electrode ECG. In other embodiments, alternative configurations of sensors or transducers (e.g., less than ten electrodes) can be used to acquire a standard or non-standard ECG signal. [0034] A representative ECG signal is schematically illustrated in FIG. 2 . The ECG signal can include [G] beats including beat-one B 1 through beat-[G] B G where [G] is a value greater than one. As used herein and in the appended claims, a capital letter in brackets represents a quantity, and a capital letter without brackets is a reference character (similar to a typical reference numeral). [0035] The data acquisition module can include filtering and digitization components for producing digitized ECG data representing the ECG signal. In some embodiments, the ECG data can be filtered using low pass and baseline wander removal filters to remove high frequency noise and low frequency artifacts. The ECG data can, in some embodiments, be filtered by removing arrhythmic beats from the ECG data and by eliminating noisy beats from the ECG data. [0036] The cardiac monitoring system 10 can include a processor and a memory associated with the processor. The processor can execute a software program stored in the memory to perform a method of the invention as illustrated in FIG. 3 . FIG. 3 is a flow chart of a method of the invention used to determine and display alternans data of an ECG signal. Although the cardiac monitoring system 10 is described herein as including a single processor that executes a single software program, it should be understood that the system can include multiple processors, memories, and/or software programs. Further, the method of the invention illustrated in FIG. 3 can be performed manually or using other systems. [0037] As shown in FIG. 3 , the processor can receive (at 100 ) ECG data representing an ECG signal. The acquired ECG data can be received (e.g., from a patient in real-time via the data acquisition module or from storage in a memory device) and can be processed as necessary. The ECG data can represent continuous and/or non-continuous beats of the ECG signal. In one embodiment, the ECG data, or a portion thereof, can be parsed into a plurality of data sets. Each data set can represent a portion of a respective beat B of the ECG signal (e.g., the T-wave portion of a respective beat B of the ECG signal), a portion of a respective odd or even median beat of the ECG signal, a portion of a respective odd or even mean beat of the ECG signal, and the like. The parsed data sets can be saved in an array (e.g., a waveform array). In other embodiments, the ECG data can be saved in a single data set, or alternatively, saved in multiple data sets. [0038] The processor can determine (at 102 ) a quantity [C] of values W representing a quantity [D] of morphology features F of a beat B (e.g., beat-one B 1 ) of a quantity [G] beats, where [C] and [D] are each a quantity greater than or equal to one. In some embodiments, a single value W is determined for each morphology feature F (i.e., the quantity of [C] is equal to the quantity of [D]). However, in some embodiments, multiple values W are determined for a single morphology feature F and/or a single value W is determined for multiple morphology features F. Determining a quantity [C] of values W representing a quantity [D] of morphology features F can be repeated for a quantity [H−1] of beats of the quantity [G] of beats represented in the collected ECG data where a quantity [H] is greater than or equal to one and less than or equal to the quantity [G]. [0039] In some embodiments, any morphology features F of the beats B can be determined. FIGS. 4-9 illustrate some examples of such morphology features F. FIG. 4 illustrates a maximum morphology feature (i.e., the maximum value of the data set representing the T-wave portion of a respective beat). FIG. 5 illustrates a minimum morphology feature (i.e., the minimum value of the data set representing the T-wave portion of a respective beat). FIG. 6 illustrates an area morphology feature (i.e., the area between a curve formed by the data set representing the T-wave portion of a respective beat and a baseline established by the minimum value of the data set). FIG. 7 illustrates another area morphology feature (i.e., the area between a curve formed by the data set representing the T-wave portion of a respective beat and a baseline established by the maximum value of the data set and a point of the data set representing the maximum up-slope of the curve). FIG. 8 illustrates still another area morphology feature (i.e., the area between a curve formed by the data set representing the T-wave portion of a respective beat and a baseline established by the minimum value of the data set and a point of the data set representing the maximum down-slope of the curve). FIG. 9 illustrates yet another area morphology feature (i.e., the area between a curve formed by the data set representing the T-wave portion of a respective beat and a baseline established by a point of the data set representing the maximum up-slope of the curve and a point of the data set representing the maximum down-slope of the curve). Other types of maximum, minimum, and area morphology features can also be used. [0040] Other examples of morphology features that can be used include amplitude morphology features (e.g., an amplitude of a point representing the maximum down-slope of the curve formed by the data set representing the T-wave portion of a respective beat) and slope morphology features (e.g., a maximum positive slope of the curve formed by the data set representing the T-wave portion of a respective beat). Another example is mathematical model morphology features obtained by determining values representing a mathematical model of the curve formed by the data set representing the T-wave portion of a respective beat using, for example, a Gaussian function model, a power of Cosine function model, and/or a bell function model. A further example is time interval morphology features (e.g., a time interval between a maximum value and a minimum value of the data set representing a T-wave portion of a respective beat). Still another example is shape correlation morphology features obtained by determining a value representing a shape correlation of the curve formed by the data set representing the T-wave portion of a respective beat using, for example, a cross-correlation method and/or an absolute difference correlation method. An additional example is ratio morphology features (e.g., a ST:T ratio). Any other suitable morphology feature can be used in other embodiments of the invention. In some embodiments, as discussed above, the morphology feature can be determined using values of the data set(s) of the ECG data. In other embodiments, the morphology features can be determined using values representing the values of the data set(s) of the ECG data (e.g., a morphology feature of the first derivative of the curve formed by a respective data set). [0041] Morphology features can be determined using an entire parsed data set as illustrated in FIGS. 4-9 , or alternatively, using a portion thereof as illustrated in FIGS. 10 and 11 . As shown in FIG. 10 , each of the beats B can be divided up in a plurality of portions. The center of each portion can be defined by a vertical divider line. As shown in FIG. 11 , a window can be established to define the size of the portion. The window can include a single value of the data set (e.g., a value representing the point where the divider line crosses the curve formed by the data set), or values of the data set representing any number of points adjacent the intersection of the curve and the divider line. [0042] As shown in FIG. 3 , the processor can generate (at 104 ) a feature matrix. As used herein and in the appended claims, the term “matrix” includes any table of values. The generated feature matrix can include a quantity [C] of values W representing each of the quantity [D] of morphology features F for each of the quantity [H] of beats B (i.e., the feature matrix includes a quantity [C]×[H] of values W). Each value W can directly represent the determined morphology feature F (e.g., the actual value of the determined area morphology feature), or can indirectly represent the determined morphology feature (e.g., a normalized value of the determined area morphology feature). [0043] A representative column-wise feature matrix A is illustrated in FIG. 12 . The feature matrix A can include [C] columns and [H] rows. The feature matrix A can use the columns to represent the quantity [D] of morphology features F (i.e., each column includes a quantity [H] of values W of the same morphology feature as determined for each of the quantity [H] of beats B), and the rows to represent the beats B (i.e., each row includes a quantity [C] of values representing the quantity [D] of morphology features for each of the quantity [H] of beats). The values W of the morphology features F can be represented in the illustrated feature matrix A using the notation W IBJ and F I B J where I is a value between one and [C], the quantity of [C] being equal to the quantity of [D], and J is a value between one and [H]. In other embodiments, the feature matrix A can be arranged in other suitable manners. In yet other embodiments, the values W representing the morphology features F can be saved for later processing. [0044] As shown in FIG. 3 , the processor can preprocess (at 106 ) the feature matrix A. In some embodiments, a principal component analysis (PCA) can be performed on the feature matrix A. PCA involves a multivariate mathematical procedure known as an eigen analysis which rotates the data to maximize the explained variance of the feature matrix A. In other words, a set of correlated variables are transformed into a set of uncorrelated variables which are ordered by reducing variability, the uncorrelated variables being linear combinations of the original variables. PCA is used to decompose the feature matrix A into three matrices, as illustrated in FIG. 13 . The three matrices can include a matrix U, a matrix S, and a matrix V. [0045] The matrix U can include the principal component vectors (e.g., the first principal component vector u 1 , the second principal component vector u 2 , . . . , the pth principal component vector u p ). The principal component vectors are also known as eigen vectors. The first principal component vector u 1 can represent the most dominant variance vector (i.e., the first principal component vector u 1 represents the largest beat-to-beat variance), the second principal component vector u 2 can represent the second most dominant variance vector, and so on. [0046] The S Matrix can include the principal components (e.g., the first principal component S 1 , the second principal component S 2 , . . . , the pth principal component S p ). The first principal component S 1 can account for as much of the variability in the data as possible, and each succeeding principal component S can account for as much of the remaining variability as possible. The first principal component S 1 can be used to determine alternans data (e.g., the square-root of the first PCA component S 1 can provide an estimation of the amplitude of the most dominant alternans pattern of variation). In some embodiments, the second principal component S 2 and the third principal component S 3 can also provide useful alternans data. [0047] The matrix V is generally known as the parameter matrix. The matrix V can be raised to a power of T. In other embodiments, the preprocessing of the feature matrix A can include other types of mathematical analyses. [0048] The robustness of the preprocessing of the feature matrix A can be enhanced by increasing the quantity of [H] as the quantity of [D] increases. In other words, an increase in the number of morphology features F represented in the feature matrix A generally requires a corresponding increase in the number of beats B for which the morphology features F are being determined; The correspondence between the quantities of [D] and [H] is often based on the dependency between each of the [D] morphology features F. In some embodiments, the quantity of [H] is greater than or equal to 32 and less than or equal to 128. In other embodiments, the quantity of [H] is less than 32 or greater than 128. In some embodiments, the value of [H] is adaptively changed in response to a corresponding change in the level of noise in the measured ECG signal. [0049] As shown in FIG. 3 , the processor can determine (at 108 ) [E] points L using data corresponding to at least some of the values W, [E] being a quantity greater than or equal to one. The data corresponding to the values W can include at least one value W, at least one value of a principal component vector (e.g., the first principal component vector u 1 ), and/or at least one value of any other data that corresponds to the values W. Each point L can include a first value (e.g., one of an X-value and a Y-value) determined using a first mathematical function Feature(beat+[N]), and a second value (e.g., the other of the X-value and the Y-value) determined using a second mathematical function Feature(beat), [N] being a quantity greater than or equal to one. Each of the first and second values of the points L represents a feature of the data corresponding to the values W. In the illustrated embodiment, the feature is a difference feature Q (i.e., the difference in amplitude between two values of the data corresponding to the values W as specified by the respective mathematical function). In other embodiments, the first and second values of the points L can represent another difference features (e.g., an absolute difference feature, a normalized difference feature, a square-root difference feature, and the like), or any other mathematically-definable feature of the data corresponding to the values W. For example, the feature can include a value feature where the feature is equal to a specified value of the data corresponding to the determined values W. [0050] Equations 1 and 2 shown below define an example of the mathematical functions Feature(beat+[N]) and Feature(beat), respectively. The first values of the points L determined using the mathematical function Feature(beat+[N]) can represent a difference feature Q K+[N] and the second values of the points L determined using the mathematical function Feature(beat) can represent the difference feature Q K , where K is a value equal to a beat (i.e., the beat for which the respective mathematical function is being used to determine either the first or second value of a point L). Feature(beat+[N])= W (beat+2[N]) −W (beat+[N]) =Q K+[N]   [e1] Feature(beat)= W (beat+[N]) −W (beat) =Q K   [e2] [0051] Tables 1-3 shown below represent the determination of points L using the mathematical functions Feature(beat+[N]) and Feature(beat) as defined in Equations 1 and 2 for [N]=1, 2, and 3, respectively. Equations 3 and 4 shown below define the mathematical functions Feature(beat+[N]) and Feature(beat) for [N]=1. Feature(beat+1)= W (beat+2) −W (beat+1) =Q K+1   [e3] Feature(beat)= W (beat+1) −W (beat) =Q K   [e4] Equations 5 and 6 shown below define the mathematical functions Feature(beat+[N]) and Feature(beat) for [N]=2. Feature(beat+2)= W (beat+4) −W (beat+2) =Q K+2   [e5] Feature(beat)= W (beat+2) −W (beat) =Q K   [e6] Equations 7 and 8 shown below define the mathematical functions Feature(beat+[N]) and Feature(beat) for [N]=3. Feature(beat+3)= W (beat+6) −W (beat+3) =Q K+3   [e7] Feature(beat)= W (beat+3) −W (beat) =Q K   [e8] [0052] As shown by Equations 3-8, the offset between the difference feature Q K+[N] and the difference feature Q K is dependent on the value of [N]. For [N]=1, the first value of the point L is determined by finding the difference between the value W of the second next beat B I+2 and the value W of the next beat B I+1 , while the second value of the point L is determined by finding the difference between the value W of the next beat B I+1 and the value W of the current beat B I . For [N]=2, the first value of the point L is determined by finding the difference between the value W of the fourth next beat B I+4 and the value W of the second next beat B I+2 , while the second value of the point L is determined by finding the difference between the value W of the second next beat B I+2 and the value W of the current beat B I . For [N]=3, the first value of the point L is determined by finding the difference between the value W of the sixth next beat B I+6 and the value W of the third next beat B I+3 , while the second value of the point L is determined by finding the difference between the value W of the third next beat B I+3 and the value W of the current beat B I . Accordingly, the first values of the points L determined using the first mathematical function Feature(beat+[N]) are offset relative to the second values of the points L determined using the second mathematical function Feature(beat) by a factor of [N]. For example, for [N]=1, the first mathematical function Feature(beat+[N]) determines Feature(2) . . . Feature(Z+1) for beat-one B 1 through beat-(Z) B Z , while the second mathematical function Feature(beat) determines Feature(1) . . . Feature(Z) for beat-one B 1 through beat-(Z) B Z ; for [N]=2, the first mathematical function Feature(beat+[N]) determines Feature(3) . . . Feature(Z+2) for beat-one B 1 through beat-(Z) B Z , while the second mathematical function Feature(beat) determines Feature(1) . . . Feature(Z) for beat-one B 1 through beat-(Z) B Z ; for [N]=3, the first mathematical function Feature(beat+[N]) determines Feature(4) . . . Feature(Z+3) for beat-one B 1 through beat-(Z) B Z while the second mathematical function Feature(beat) determines Feature(1) . . . Feature(Z) for beat-one B 1 through beat-(Z) B Z . This offset relationship between the first values of the points L determined using the first mathematical function Feature(beat+[N]) and the second values of the points L determined using the second mathematical function Feature(beat) is further illustrated in Tables 1-3. [0053] In Tables 1-3 shown below, the “Beat” column can represent respective beats B of the ECG signal and the “Feature Value” column can represent a value W of a morphology feature F of the corresponding respective beat B (e.g., an area morphology feature). As discussed above, the points L can be generated using values of other data corresponding to the determined values W. Also in Tables 1-3, an asterisk (*) represents an undetermined value of the point L (i.e., a value of the point L for which feature values W corresponding to beats B subsequent to the listed beats B 1 -B 12 are required to determine the value of the point L), “f(b+N)” represents the mathematical function Feature(beat+[N]), and “f(b)” represent the mathematical function Feature(beat). Each point L shown in Tables 1-3 includes an X-value dtermined using the first mathematical function Feature(beat+[N]) and a Y-value determined using the second mathematical function Feature(beat). [N] = 1 Feature f(b + N) = W (b+2N) − W (b+N) f(b) = W (b+N) − W (b) Feature Map Beat Value f(b + 1) = W (b + 2) − W (b+1) f(b) = W (b+1) − W (b) Point Group 1 2 f(2) = 3 − 5 = −2 f(1) = 5 − 2 = 3 (−2, 3) A 2 5 f(3) = 6 − 3 = 3 f(2) = 3 − 5 = −2 (3, −2) B 3 3 f(4) = 2 − 6 = −4 f(3) = 6 − 3 = 3 (−4, 3) A 4 6 f(5) = 4 − 2 = 2 f(4) = 2 − 6 = −4 (2, −4) B 5 2 f(6) = 3 − 4 = −1 f(5) = 4 − 2 = 2 (−1, 2) A 6 4 f(7) = 7 − 3 = 4 f(6) = 3 − 4 = −1 (4, −1) B 7 3 f(8) = 3 − 7 = −4 f(7) = 7 − 3 = 4 (−4, 4) A 8 7 f(9) = 5 − 3 = 2 f(8) = 3 − 7 = −4 (2, −4) B 9 3 f(10) = 3 − 5 = −2 f(9) = 5 − 3 = 2 (−2, 2) A 10 5 f(11) = 7 − 3 = 4 f(10) = 3 − 5 = −2 (4, −2) B 11 3 f(12) = W 13 − 7 = * f(11) = 7 − 3 = 4 (*, 4) A 12 7 f(13) = W 14 − W 13 = * f(12) = W 13 − 7 = * (*, *) B [0054] [N] = 2 Feature f(b + N) = W (b+2N) − W (b+N) f(b) = W (b+N) − W (b) Feature Map Beat Value f(b + 2) = W (b+4) − W (b+2) f(b) = W (b+2) − W (b) Point Group 1 2 f(3) = 2 − 3 = −1 f(1) = 3 − 2 = 1 (−1, 1) A 2 5 f(4) = 4 − 6 = −2 f(2) = 6 − 5 = 1 (−2, 1) B 3 3 f(5) = 3 − 2 = 1 f(3) = 2 − 3 = −1 (1, −1) A 4 6 f(6) = 7 − 4 = 3 f(4) = 4 − 6 = −2 (3, −2) B 5 2 f(7) = 3 − 3 = 0 f(5) = 3 − 2 = 1 (0, 1) A 6 4 f(8) = 5 − 7 = −2 f(6) = 7 − 4 = 3 (−2, 3) B 7 3 f(9) = 3 − 3 = 0 f(7) = 3 − 3 = 0 (0, 0) A 8 7 f(10) = 7 − 5 = 2 f(8) = 5 − 7 = −2 (2, −2) B 9 3 f(11) = W 13 − 3 = * f(9) = 3 − 3 = 0 (*, *) A 10 5 f(12) = W 14 − 7 = * f(10) = 7 − 5 = 2 (*, *) B 11 3 f(13) = W 15 − W 13 = * f(11) = W 13 − 3 = * (*, *) A 12 7 f(14) = W 16 − W 14 = * f(12) = W 14 − 7 = * (*, *) B [0055] [N] = 3 Feature f(b+N) = W (b+2N) − W (b+N) f(b) = W (b+N) − W (b) Feature Map Beat Value f(b+3) = W (b+6) − W (b+3) f(b) = W (b+3) − W (b) Point Group 1 2 f(4) = 3 − 6 = −3 f(1) = 6 − 2 = 4 (−3, 4) A 2 5 f(5) = 7 − 2 = 5 f(2) = 2 − 5 = −3 (5, −3) B 3 3 f(6) = 3 − 4 = −1 f(3) = 4 − 3 = 1 (−1, 1) A 4 6 f(7) = 5 − 3 = 2 f(4) = 3 − 6 = −3 (2, −3) B 5 2 f(8) = 3 − 7 = −4 f(5) = 7 − 2 = 5 (−4, 5) A 6 4 f(9) = 7 − 3 = 4 f(6) = 3 − 4 = −1 (4, −1) B 7 3 f(10) = W 13 − 5 = * f(7) = 5 − 3 = 2 (*, *) A 8 7 f(11) = W 14 − 3 = * f(8) = 3 − 7 = −4 (*, *) B 9 3 f(12) = W 15 − 7 = * f(9) = 7 − 3 = 4 (*, *) A 10 5 f(13) = W 16 − W 13 = * f(10) = W 13 − 5 = * (*, *) B 11 3 f(14) = W 17 − W 14 = * f(11) = W 14 − 3 = * (*, *) A 12 7 f(15) = W 18 − W 15 = * f(12) = W 15 − 7 = * (*, *) B [0056] FIG. 14 illustrates a plot of the feature values from Tables 1-3 for beat-one B 1 through beat-seven B 7 where each peak and each valley of the plot can represent a respective feature value W (e.g., value-one W 1 which represents beat-one B 1 , value-two W 2 which represents beat-two B 2 , . . . , value-seven W 7 which represents beat-seven B 7 ). [0057] FIG. 15 illustrates for [N]=1 how the mathematical functions Feature(beat+[N]) and Feature(beat) determine the first and second values of the points L which represent the difference features Q K and Q K+1 . For [N]=1, the seven values (i.e., value-one W 1 through value-seven W 7 ) generate six difference features (i.e., difference feature-one Q 1 through difference feature-six Q 6 ). Referring to Table 1, the first mathematical function generates difference feature-two Q 2 through difference feature-six Q 6 for beat-one B 1 through beat-five B 5 , respectively, using the seven values, and the second mathematical function generates difference feature-one Q 1 through difference feature-six Q 6 for beat-one B 1 through beat-six B 6 , respectively, using the seven values. [0058] The difference feature Q is illustrated in FIG. 15 as dotted-line arrows extending between two specified values of the plot of FIG. 14 . As an example, to determine difference feature-three Q 3 (i.e., the first value of the point L as determined by the first mathematical function Feature(beat+[N]) for beat-two B 2 , the second value of the point L as determined by the second mathematical function Feature(beat) for beat-three B 3 ), the difference can be found between value-four W 4 which represents beat-four B 4 and value-three W 3 which represents beat-three B 3 . Similarly, to determine difference feature-six Q 6 (i.e., the first value of the point L as determined by the first mathematical function Feature(beat+[N]) for beat-two B 5 , the second value of the point L as determined by the second mathematical function Feature(beat) for beat-six B 6 ), the difference can be found between value-four W 7 which represents beat-seven B 7 and value-six W 6 which represents beat-six B 6 . [0059] FIG. 16 illustrates for [N]=2 how the mathematical functions Feature(beat+[N]) and Feature(beat) determine the first and second values of the points L which represent the difference features Q K and Q K+2 . For [N]=2, the seven values (i.e., value-one W 1 through value-seven W 7 ) generate five difference features (i.e., difference feature-one Q 1 through difference feature-five Q 5 ). Referring to Table 2, the first mathematical function generates difference feature-three Q 3 through difference feature-five Q 5 for beat-one B 1 through beat-three B 3 , respectively, using the seven values, and the second mathematical function generates difference feature-one Q 1 through difference feature-five Q 5 for beat-one B 1 through beat-five B 5 , respectively, using the seven values. [0060] The difference feature Q is illustrated in FIG. 16 as dotted-line arrows extending between two specified values of the plot of FIG. 14 . As an example, to determine difference feature-three Q 3 (i.e., the first value of the point L as determined by the first mathematical function Feature(beat+[N]) for beat-one B 1 , the second value of the point L as determined by the second mathematical function Feature(beat) for beat-three B 3 ), the difference can be found between value-five W 5 which represents beat-five B 5 and value-three W 3 which represents beat-three B 3 . Similarly, to determine difference feature-five Q 5 (i.e., the first value of the point L as determined by the first mathematical function Feature(beat+[N]) for beat-three B 3 , the second value of the point L as determined by the second mathematical function Feature(beat) for beat-five B 5 ), the difference can be found between value-four W 7 which represents beat-seven B 7 and value-five W 5 which represents beat-five B 5 . [0061] FIG. 17 illustrates for [N]=3 how the mathematical functions Feature(beat+[N]) and Feature(beat) determine the first and second values of the points L which represent the difference features Q K and Q K+3 . For [N]=3, the seven values (i.e., value-one W 1 through value-seven W 7 ) generate four difference features (i.e., difference feature-one Q 1 through difference feature-four Q 4 ). Referring to Table 3, the first mathematical function generates difference feature-four Q 4 for beat-four B 4 using the seven values, and the second mathematical function generates difference feature-one Q 1 through difference feature-four Q 4 for beat-one B 1 through beat-four B 4 , respectively, using the seven values. [0062] The difference feature Q is illustrated in FIG. 17 as dotted-line arrows extending between two specified values of the plot of FIG. 14 . As an example, to determine difference feature-three Q 4 (i.e., the first value of the point L as determined by the first mathematical function Feature(beat+[N]) for beat-one B 1 , the second value of the point L as determined by the second mathematical function Feature(beat) for beat-three B 3 ), the difference can be found between value-seven W 7 which represents beat-seven B 7 and value-four W 4 which represents beat-four B 4 . [0063] As shown by the “Group” column of Tables 1-3, each point L can be assigned to a respective group (e.g., group A or group B). The points L representing each odd beat (e.g., beat-one B 1 , beat-three B 3 , . . . , beat-eleven B 11 ) can be assigned to a first group (i.e., group A), and the points representing each even beat (e.g., beat-two B 2 , beat-four B 4 , . . . , beat-twelve B 12 ) can be assigned to a second group (i.e., group B). The points L can be assigned to group A and group B in this manner to represent a proposed odd-even alternans pattern of variation (i.e., ABAB . . . ). In other embodiments, the points L can be alternatively assigned to groups to represent other proposed alternans patterns of variation (e.g., AABBAABB . . . , AABAAB . . . , and the like). [0064] As shown in FIG. 3 , the processor can plot (at 110 ) a feature map [e.g., a feature map of Feature(beat+[N]) versus Feature(beat)]. Both groups of points L (e.g., group A and group B) can be plotted on the same axis to generate the feature map. The polarity of the differences of the group A points are inverted relative to the polarities of the differences of the group B points. As a result, plotting the points L determined using the mathematical functions Feature(beat) and Feature(beat+[N]) as defined by Equations 1 and 2 can accentuate any difference between the values specified by the mathematical functions Feature(beat) and Feature(beat+[N]). The inverted polarity of the differences between the first and second groups is illustrated in FIGS. 15-17 where the direction of the dotted-line arrows that represent the difference features Q alternates between adjacent difference features Q. [0065] The feature map provides a visual indication of the divergence of the two groups of points, and thus the existence of a significant alternans pattern of variation. If there is a significant ABAB . . . alternans pattern of variation, the two groups of points will show separate clusters on the feature map (for example, as shown in FIGS. 20 and 22 ). If there is not a significant ABAB . . . alternans pattern of variation, the feature map will illustrate a more random pattern of points from the two groups (for example, as shown in FIG. 21 ). [0066] FIGS. 18 and 19 illustrate two examples of feature maps. The [E] points plotted to generate the feature maps of FIGS. 18 and 19 were determined using ECG data representative of an ECG signal having a 5 microvolt TWA pattern of variation, 20 microvolts of noise, and 20 milliseconds of offset, where [H] is equal to 128. The first and second groups of points can be distinguished by the markers utilized to represent the points of the group (i.e., the first group of points, group A, can include asterisks shaped markers, and the second group of points, group B, can include round markers). Lines can be used to connect sequential markers of each group (e.g., for group A, point-two P 2A can be connected to each of point-one P 1A and point-three P 3A by lines). [0067] The feature map of FIG. 18 illustrates a plot of points determined using values directly from the feature matrix A (i.e., the feature matrix A was not preprocessed using a principal component analysis or other mathematical analysis). As illustrated in FIG. 18 , the points of the first and second groups are intermixed (i.e., the feature map illustrates a random pattern of the points from the two groups). Accordingly, the feature map of FIG. 18 does not illustrate the presence of a significant divergence of the two groups of points, and thus, does not indicate the existence of a significant alternans pattern of variation. [0068] The feature map of FIG. 19 illustrates a plot of points determined using values of a first principal vector u 1 . The first principal vector u 1 is a result of a principal component analysis performed on the same feature matrix A from which the values used to determine the points L plotted in FIG. 18 were obtained. As illustrated in FIG. 19 , although the first and second groups of points are partially overlapped, the first group of points is primarily positioned in the upper-left quadrant of the feature map and the second group of points is primarily positioned in the lower-right quadrant of the feature map. Accordingly, the feature map of FIG. 19 appears to illustrate the presence of a significant divergence of the two groups of points, and thus, a significant alternans pattern of variation may exist. [0069] Although FIGS. 18 and 19 illustrate the same ECG data, the feature map of FIG. 19 indicates the existence of an alternans pattern of variation, while the feature map of FIG. 18 does not. The effect of noise and time shift in the measured ECG signal on the determined alternans data is clearly indicated by the feature maps of FIGS. 18 and 19 . Preprocessing the feature matrix A increases the robustness of the determination of alternans data by limiting the effect of noise and time shift in the measured ECG signal. [0070] In some embodiments, multiple feature maps can be generated for various quantities of [N] using the same set of values (e.g., the feature maps for [N]=1, 2, and 3, respectively, can be generated using the points determined in Tables 1-3). The display of multiple feature maps can further verify the existence of a significant alternans pattern of variation for the proposed alternans pattern of variation (e.g., a ABAB . . . alternans pattern of variation). [0071] FIGS. 20-22 illustrate feature maps for [N]=1, 2, and 3, respectively, where the points plotted in each of the feature maps were determined using the same set of values. The divergence of the first and second groups of points in the feature maps of FIGS. 20 and 22 in combination with the lack of divergence of the first and second groups of points in the feature map of FIG. 21 provides visual evidence that the proposed ABAB . . . alternans pattern of variation is correct. [0072] The operator can change the proposed alternans pattern of variation (i.e., change the grouping of the points to a different alternans pattern of variation) if the feature maps for [N]=1, 2, and 3 do illustrate differing divergence patterns for [N]=1 and 3 and [N]=2, respectively. For example, if the two groups of points diverge in the feature map for [N]=1 and 2, but not for the feature maps of [N]=3, the ECG signal represented by the values used to determine the points for the feature maps does not represent the proposed ABAB . . . alternans pattern of variation. However, the ECG signal can include a different alternans pattern of variation. Reassignment of the [E] points to different groups can be used to test a different proposed alternans pattern of variation. [0073] As shown in FIG. 3 , the processor (at 112 ) can statistically analyze the data plotted in the feature map. Although the feature map provides a visual indication of the existence of a significant alternans pattern of variation, the feature map does not provide a quantitative measure of the confidence level of the alternans pattern of variation. Accordingly, the data plotted in the feature map, or similar types of data that are not plotted in a feature map, can be statistically analyzed to provide such quantitative measures of the confidence level of the alternans pattern of variation. [0074] In some embodiments, a paired T-test can be performed on the first and second groups of points. A paired T-test is a statistical test which is performed to determine if there is a statistically significant difference between two means. The paired T-test can provide a p-value (e.g., p=0.001). In one embodiment, the confidence level is increased (i.e., a significant alternans pattern of variation exists) when the p-value is less than 0.001. In other embodiments, other suitable threshold levels can be established. [0075] In some embodiments, a cluster analysis (e.g., a fuzzy cluster analysis or a K-mean cluster analysis) can be performed on the [E] points to determine a first cluster of points and a second cluster of points. The cluster analysis can also generate a first center point for the first cluster and a second center point for the second cluster. The first and second clusters of points can be compared with the first and second groups of points, respectively. A determination can be made of the number of clustered points that match the corresponding grouped points. For example, if point-one L 1 and point-two L 2 are clustered in the first cluster, point-three L 3 and point-four L 4 are clustered in the second cluster, point-one L 1 , point-two L 2 , and point-three L 3 can be grouped in the first group, and point-four L 4 can be grouped in the second group. Clustered point-three L 3 does not correspond to grouped point-three L 3 , thereby resulting in a 75% confidence level. The confidence level can represent the percentage of clustered points that match the corresponding grouped points. In one embodiment, a confidence level about 90% can be a high confidence level, a confidence level between 60% and 90% can be a medium confidence level, and a confidence level below 60% can be a low confidence level. In other embodiments, the thresholds for the high, medium, and/or low confidence levels can be other suitable ranges of percentages or values. [0076] As shown in FIG. 3 , the processor can determine (at 114 ) an estimate of an amplitude of the alternans pattern of variation. As discussed above, in one embodiment, the square-root of a principal component (e.g., the first principal component S 1 ) can be used to provide an estimate of the amplitude. In other embodiments, a distance can be determined between a first center point of a first group of points and a second center point of a second group of points. The center points can include the center points of the first and second groups of points A and B as determined using a mathematical analysis (e.g., by taking the mean or median of the values of the points for each respective group), the center points provided by the Paired T-test, the center points provided by the cluster analysis, or any other determined center points that represent the ECG data. [0077] FIG. 23 illustrates a distance measurement between the first and second center points. The distance can be determined using Equation 9 shown below, where the first center point includes an X-value X 1 and a Y-value Y 1 and the second center point includes an X-value X 2 and a Y-value Y 2 . Amplitude ESTIMATE =√{square root over (( X 1 −X 2 ) 2 +( Y 1 −Y 2 ) 2 )}  [e9] [0078] The amplitude of the alternans pattern of variation often depends on the [D] morphology features used to determine the values W. Accordingly, the estimated amplitude is generally not an absolute value that can be compared against standardized charts. However, comparisons can be generated for estimated amplitudes of alternans patterns of variation based on the morphology features F that are determined and the processing step that is used. [0079] As shown in FIG. 3 , the processor can report (at 116 ) alternans data to a caregiver and/or the processor can store the alternans data. The alternans data (e.g., the feature maps, the estimated amplitudes of the alternans pattern of variation, the confidence level of the alternans pattern of variation, the uncertainty level of the alternans pattern of variation, the p-value of the alternans pattern of variation, and the like) can be reported using any suitable means (e.g., output to a suitable output device such as a display, a printer, and the like). [0080] As shown in FIG. 3 , in some embodiments, the processor can plot (at 118 ) a spectral graph using values resulting from preprocessing the feature matrix (e.g., the values of the first principal component vector u 1 ). FIGS. 24 and 25 illustrate two examples of spectral graphs. The values used to generate the spectral graphs of both FIGS. 24 and 25 were determined using ECG data representative of an ECG signal having a 5 microvolt TWA pattern of variation, 20 microvolts of noise, and 20 milliseconds of offset, where [H] is equal to 128. [0081] FIG. 24 illustrates a spectral graph generated using values directly from the feature matrix A (i.e., the feature matrix A was not preprocessed using a principal component analysis or other mathematical analysis). As illustrated in FIG. 24 , the spectral graph does not include a dominant frequency at half of the beat sample frequency, but instead includes a number of frequency spikes having varying amplitudes. Accordingly, the spectral graph of FIG. 24 does not indicate the existence of a significant alternans pattern of variation. FIG. 25 illustrates a spectral graph generated using values of a first principal vector u 1 . The first principal vector u 1 is a result of a principal component analysis performed on the same feature matrix A from which the values used to generate the spectral graph of FIG. 24 were obtained. FIG. 25 illustrates a single frequency spike at half of the beat sample frequency. Accordingly, unlike the spectral graph of FIG. 24 , the spectral graph of FIG. 25 appears to illustrate the presence of a significant alternans pattern of variation. The effect of noise and time shift in the measured ECG signal on the determined alternans data is indicated by the spectral graphs of FIGS. 24 and 25 . Preprocessing the feature matrix A increases the robustness of the determination of alternans data when using spectral domain methods.
Method and apparatus for determining alternans data of an ECG signal. The method can include determining at least one value representing at least one morphology feature of each beat of the ECG signal and generating a set of data points based on a total quantity of values and a total quantity of beats. The data points can each include a first value determined using a first mathematical function and a second value determined using a second mathematical function. The method can also include several preprocessing algorithms to improve the signal to noise ratio. The method can also include separating the data points into a first group of points and a second group of points and generating a feature map by plotting the first group of points and the second group of points in order to assess an alternans pattern of variation. The feature map can be analyzed by statistical tests to determine the significance difference between groups and clusters.
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PRIOR APPLICATION [0001] This application is a division of U.S. patent application Ser. No. 09/462,696 filed Jul. 18, 2000, now U.S. Pat. No. ______. FIELD OF THE INVENTION [0002] The present invention relates to refiner plates for papermaking and refining of lignocellulosic and other natural and synthetic fibrous materials in the manufacture of paper, paperboard, and fiberboard products. In particular, the invention relates to replacable refiner fillings and to method of manufacture. BACKGROUND OF THE INVENTION [0003] In nearly all milled or fabricated refiner plates, and in many cast refiner plates, the working surface of the refiner plate consists of clusters of parallel bars and grooves. The refiner filling disc is normally depicted as a complete circle, but in fact the filling often consists of several more-or-less pie-shaped segments which are much easier to handle when replacing a filling. [0004] U.S. Pat. No. 5,740,972 discloses improvements in replaceable refiner fillings and the manufacture of refiner fillings with working surfaces using relatively narrow, closely spaced bars on the working surface of the plate. The refiner fillings have relatively thin blades separated by shallower spacer bars having a thickness which determines the width of the grooves. [0005] The refiner fillings use a metal or other hard and durable material for the blades and spacers, which blades and spacers are then metallurgically bonded to each other along their entire intercontacting surfaces. A suitable metallurgical bond is achieved through any of several known methods including welding, diffusion bonding, brazing, or any other method which results in a joint strength approaching that of the blade or spacer material. Materials used include stainless steel blades bonded to carbon steel spacers and ceramic and metal composite materials as blade or spacer components in refiner fillings. A metal composite material which exhibits suitable strength and toughness characteristics for a particular refiner application is used for the blades of the filling, while a much less costly material may be used for the spacers. [0006] As disclosed in the '972 patent, segmental replacement disc refiner plates are produced with segments having both non-circular edges (i.e., side edges) which are not precisely radial Instead, the side edges are oblique to the precisely radial line such that the refiner plate segmental dividing line is parallel to the adjacent refiner blade. Each segment may typically have a value of 30, 45, or 60 degrees of a circle so that 12, 8, or 6 segments, respectively comprise a refiner disc. [0007] The blades of each cluster are positioned parallel to a side edge of the cluster and extend from the outer periphery toward the inner periphery of the segment. Blade obliqueness to the disc radius increases with distance normal to the side edge. It is desirable with refiner plates to avoid shallow crossing angles (i.e., high degree of obliquity to radial) of stator and rotor blades and therefore desirable to maintain blade obliqueness in a range of 3 to 20 degrees with respect to disc radial. Hence, the blade pattern is begun anew at that location in the refiner segment where increasing obliqueness approaches 20 degrees. So, the segment blade pattern is repeated at intervals to maintain blade obliqueness within a desired range over the entire working surface of a refiner filling. The repeated blade pattern is defined herein as a blade cluster characterized by a common cluster angle throughout the refiner filling. [0008] An obvious method for producing the components of a blade cluster for this type of fabricated refiner plate would consist of cutting individual blades and spacers, such that for any specified set of inside diameter, outside diameter, and cluster angle, each blade and spacer would have a unique length. The uniqueness of each component, and the relative difficulty of fitting them precisely, results in a high cost to manufacture. [0009] The present invention provides refiner fillings of the kind disclosed in the '972 patent and methods for manufacture of the fillings economically and efficiently with very significant reduction in the cost of tools and fixtures while greatly facilitating the assembly of refiner filling clusters. In particular, the invention facilitates the manufacture of refiner fillings in a preferred embodiment having a preferred range of working surface blade obliqueness to disc radial, working surface blades assembled in cluster units conforming to the range of blade obliqueness, a fixed pumping angle, and a fixed number of identical segments comprising a refiner filling. [0010] The invention also provides a barset envelope or parallelogram as defining a basic unit of manufacture of a working surface of blades and spacers, with each barset divisible into two identical blade clusters. SUMMARY OF THE INVENTION [0011] The present invention provides improvements in replaceable refiner and has as a primary objective the manufacture of refiner fillings with working surfaces using relatively narrow, closely spaced bars on the working surface of the plate. This is accomplished by using relatively thin blades preferably of stainless steel, separated by shallower spacer bars preferably of carbon steel having a thickness which determines the width of the grooves, and subsequently fusing or bonding the assembled blades and spacers into a solid piece by methods appropriate for the blade and spacer materials being used. [0012] In another primary aspect of the invention, the spacers and blades are assembled in bar sets according to a predetermined pattern, bonded together, and with each bar set cut in half to yield identical clusters. A refiner filling segment comprises a plurality of clusters bonded together. In a preferred embodiment, six clusters are assembled in edge to edge relation and bonded to form a filling segment. A complete refiner filling disc in preferred embodiment comprises eight segments. [0013] In a preferred method, a bar set of blades and spacers is the basic unit of manufacture with the bar set configuration or envelope established in a first step. The bar set envelope is a parallelogram with its long edge coincident with a refiner filling segmental edge. The segmental edge is offset from a true radius of the refiner disc as in the '972 patent, and the offset is defined as the pumping angle of the refiner filling. The offset or pumping angle is preferably in a range of 3° to 20°. The pumping angle is also defined as the angle between the first cluster blade and the disc radius, and also as the line between blade clusters. [0014] The number of blades and spacers comprising a bar set is selected so as to yield two identical clusters when the bar set is cut in half. A bar set cutting line is established between opposite outer and inner sides of the bar set parallelogram for cutting the bar set precisely into matching clusters. [0015] After the bar set parallelogram is defined, blades and spacers are assembled, alternating with each other, all in parallel with the long edges of the parallelogram and of course with the design offset edge of each refiner segment, and are bonded after assembly. Several of the blades lie across the path of the cutting line and are pre-notched at their intersection of the cutting line. [0016] After a bar set is cut into two identical bar clusters, one cluster is rotated 180° so that its outer long edge abuts the cut edge of the other cluster. A multiple of cut and rejoined clusters are assembled and bonded to form a refiner segment. [0017] The completed segment is characterized by an integer multiple of clusters in edge to edge relationship, the first blade of each cluster having the same offset angle as the segmental edge, and the blades of each cluster having the same range of obliquity from the refiner disc radius. [0018] The invention provides for a method of assembling clusters from only a few unique blade and spacer components. In the manufacturing method many of the blades are identical and all spacers are identical to simplify inventory of parts. A complete refiner filling disc may employ approximately 1000 blades and spacers with each bar set component having 18 blades and 19 spacers. The invention results in very significant reduction in the cost of tools and fixtures, and greatly facilitates the assembly of the clusters. OBJECTS OF THE INVENTION [0019] It is an object of the invention to provide refiner plates and a method for their manufacture. [0020] It is an object of the invention to provide improved refiner plates in which bars and spacers are assembled in proper order and are fused or bonded together. [0021] Another object of the invention is to provide efficient and economical manufacture of refiner fillings with predetermined pattern of blades and spacers. [0022] Other and further objects of the invention will occur to one skilled in the art with an understanding of the following detailed description of the invention or upon employment of the invention in practice. DESCRIPTION OF THE DRAWING [0023] A preferred embodiment of the invention has been chosen for purposes of illustrating the construction and operation of the invention and is shown in the accompanying drawing in which: [0024] FIG. 1 is a plan view of a refiner filling disc according to the invention. [0025] FIG. 2 is a fragmentary section view of a refining filling illustrating the positions of blades, spacers, and base plate. [0026] FIG. 3 is a plan view of a refiner filling segment according to the invention. [0027] FIG. 4 is a schematic view illustrating the geometric definition of a blade and spacer cluster according to the invention. [0028] FIGS. 5 a - 5 h are side and end elevational views of blades and spacers according to the invention. [0029] FIG. 6 illustrates the outline of adjacent bar set clusters. [0030] FIG. 7 illustrates the bar set clusters of FIG. 6 re-positioned to form a bar set envelope or parallelogram. [0031] FIG. 8 illustrates a bar set of blades and spacers assembled in a bar set envelope. [0032] FIG. 9 illustrates the bar set of FIG. 8 cut along line C-C, and re-positioned into adjacent bar set clusters ready for assembly into a refiner segment. [0033] FIG. 10 is a side elevation view of a bar set cluster along cut line C-C. DETAILED DESCRIPTION OF THE INVENTION [0034] Referring to the drawing, a preferred embodiment of a refiner disc filling 10 according to the invention comprises a supporting plate 12 to which blades 14 and spacers 16 are affixed and wherein the blades and spacers define the disc working surface 17 and intervening grooves 18 . [0035] As shown in FIGS. 1, 3 and 4 , in a preferred embodiment of the invention, the refiner disc filling 10 has defining margins in outer 20 and inner 22 concentric perimeters. The filling ( FIG. 1 ) comprises a plurality of filling segments A-B, B-C, and C-A with each segment having a plurality of bar clusters 24 . The outer and inner perimeter circles define an annular active refining zone 26 containing all the blades and spacers of the filling. [0036] In the filling segment A-B of FIG. 3 , each bar cluster 24 has an 10 oblique side edge 24 a offset from the disc radius R by a specified angle alpha defined as the pumping angle, with the cluster angle beta selected always to yield an integer quotient when divided into 360°, and also when divided into the segment fraction of a circular disc, i.e., 30°, 45°, 60°, 90°, 120°, etc. [0037] In the specific and preferred cases of: [0038] FIG. 1 , disc diameter is 16 inches, the offset angle alpha is 10°, each segment is 120° and contains 8 bar clusters, with a total of 24 bar clusters in the refiner filling, and with a cluster angle beta of 15; and [0039] FIG. 3 , disc diameter is 26 inches, the offset angle alpha is 5°, each segment is 60° and contains 8 bar clusters, with a total of 48 clusters in the refiner filling, and with a cluster angle beta of 7.5°. [0040] The schematic layout of FIG. 4 includes a 34 inch diameter disc, with 8 segments of 6 clusters each, a cluster angle beta of 7.5° and a pumping angle alpha of 10°. [0041] A primary aspect of the invention is the laying out of a cluster envelope which must fit within the inner and outer perimeter of the active refining zone of the circular filling, and within the two more or less radial cluster edges 24 a - b which divide the entire circle into an integer number of clusters. [0042] In the schematic of FIG. 4 , the active refining zone 26 is divided into 8 identical segments each defined by lines 30 tangent to an inner circle 32 , and with each segment subdivided by tangent lines or cluster radials 24 a - b into 6 identical bar cluster envelopes 36 . (The diameter of the inner circle 32 determines the pumping angle alpha by known geometric calculation). Each bar cluster envelope 36 is further defined by a chord 38 along the outer perimeter 20 between adjacent cluster radials 24 a - 24 b , and by an inner line 40 parallel to outer chord 38 and passing through the intersection I of the inner perimeter 22 and one of the cluster radials 24 a . In a finished refiner filling all blades and spacers will lie within the cluster envelope 36 generated in this manner. [0043] The manufacturing method first prepares a bar set pattern or envelope in the form of a parallelogram. The bar set envelope receives a precise number of blades and spacers within the envelope's exterior dimensions for yielding two identical bar clusters when the envelope is cut into equal pieces. Every cluster 24 of the refiner filling is produced in this way. [0044] An outline of adjacent bar set clusters 24 l - r appears in FIG. 6 including oblique side edges 24 a , 24 b , outer chord lines 38 , inner lines 40 and cut lines C-C. [0045] The left-hand bar set cluster outline 24 l of FIG. 6 is re-positioned in FIG. 7 alongside cluster 24 r to form a bar set envelope or parallelogram 42 . The bar set envelope 42 consists of a pair of bar clusters with parallel oblique side edges 24 a , 24 b , and with the clusters abutting each other along their cut edges C-C. The ends of the bar set envelope parallelogram are formed by chords 38 and by parallel lines 40 . This arrangement is shown in FIGS. 6 and 7 in which it is seen that one cluster 24 r is in correct operational position and the other cluster 24 l is rotated 180° to form the parallelogram pattern. In FIG. 6 representing the operating position of adjacent clusters 24 l - r , cut edges C-C appear as the left edge of each cluster. In FIG. 7 , cut edges C-C abut and define the line along which the bar set of assembled bars and spacers is cut by suitable means. The bar set envelope 42 defines the basic manufacturing unit for assembling and temporarily attaching blades and spacers prior to final metallurgical or other suitable bonding. The bar set envelope also facilitates use of identical bars and identical spacers throughout the entire filling. [0046] The blades 46 and spacer 48 are shown in FIG. 5 a - h and comprise 30 three blades types, including a long or unnotched blade 46 a , an end notched blade 46 b and a center notched blade 46 c. [0047] It is very advantageous that each blade's inner end be tapered 50 as shown in FIG. 5 , in order to prevent fibrous material from being stapled over the end of a blade positioned at inner perimeter of the active filler zone. Such stapling can eventually lead to plugging or otherwise interrupting the uniform flow of fibrous material into the active refining area. Accordingly, a taper is formed at the end of blade 46 a , and also as defining margins of notches 49 of blades 46 b and 46 c since, after a bar set is cut in half, each tapered notch margin becomes a blade inner end as is apparent in FIGS. 8, 9 and 10 . [0048] Once the bar set cluster envelope 42 is defined and the desired blade and spacer widths have been selected, a precise number and length of blades and spacers are stacked to form a parallelogram of particular width, length and bar set angle theta as in FIG. 8 . The dimensions of the bar set are such that the bar set may be cut in half along line C-C to form two identical bar clusters. [0049] In the specific example of FIG. 8 , blades 46 and spacers 48 are assembled alternately within the parallelogram. Blades with tapered ends 50 are put into position outside the barset cutting line C-C. Blades intersecting the cutting line are notched with the notch 49 occurring where the cutting line passes. This is shown in FIG. 8 where the cutting line passes notches in blades 46 b and 46 c. [0050] After the blades and spacers are assembled and temporarily or permanently bonded, the barset is cut along the dividing line C-C into identical bar clusters 24 . As shown in FIG. 9 , after cutting, one of the bar set clusters is re-positioned by rotation of 180° for assembly into a refiner segment. The segments include bolt holes 52 ( FIGS. 2, 3 ) for attachment to a refiner disc. [0051] The method of manufacture proceeds as follows. The layout ( FIG. 4 ) of a refiner filling is established including outer 28 and inner 22 perimeter circles defining an active refiner zone 26 . A pumping angle alpha and a cluster angle beta are selected (or known) for the refiner filling and located in the layout. A relatively small cluster angle results in a short outer chord 38 which is desirable. A core circle 32 tangent to the pumping angle oblique 24 a is formed to which circle all additional oblique lines 24 a and 24 b are tangent. In the example shown in FIG. 4 , a cluster angle beta of 7½° is selected. A pumping angle of approximately 10° is selected and the core circle 32 is drawn. [0052] Next, the number of segments (8 in the example of FIG. 4 ) is set and defined by 8 equally spaced oblique lines 30 . The number of clusters per segment is determined (6 in the example) by equally spaced oblique lines 24 . [0053] In the layout, a cluster envelope 36 is defined by adjacent obliques 24 a - b , a chord 38 between the intersections of the obliques and the outer perimeter circle 28 , and by an inner line 40 parallel to the chord and passing through the intersection I of the inner perimeter circle 22 and one oblique 24 a. [0054] A bar set envelope 42 ( FIGS. 6 and 7 ) is defined by a pair of cluster envelopes 24 l - r with one cluster 24 r oriented as in FIG. 3 , and the other cluster envelope 241 rotated 180° to define a parallelogram with the one cluster envelope. That is, the left edges 24 b of the cluster envelopes 24 l - r seen in FIG. 7 define a cutting line C-C along which the bar set is cut to form the cluster envelopes. The bar set envelope next receives blades and spacers sized in length and width to fit precisely within the envelope. [0055] An assembly of blades and spacers appears in FIG. 8 , including end tapered blades, and pre-notched blades with notches defined by tapered ends and with the notches situated in the cutting line. After assembly the blades and spacers are affixed to each other by means appropriate to the materials used. For example, blades and spacers may be metallurgically bonded entirely throughout the interconnecting surfaces of blades and spacers for the bar set, and then cut along the cutting line to form bar clusters. Alternatively, the bars and spacers maybe temporarily attached as by tack welding prior to cutting, and bonded after cutting. [0056] FIG. 10 illustrates the cut edge of a bar set cluster along line C-C. In this profile view the cut line diagonally intersects blades 46 c through their notches, and diagonally through spacers 48 . Blade 46 a is not cut and terminates in tapered end 50 . [0057] Various changes may be made to the structure embodying the principles of the invention. The principles of the invention, while described in preferred embodiment of refiner disc segments, are also applicable to other configurations of refiner fillings. For example, the invention also has application to working surfaces of refiners in conical or other types of refiners. [0058] The foregoing embodiments are set forth in an illustrative and not in a limiting sense. The scope of the invention is defined by the claims appended hereto.
Replaceable refiner fillings used for refining of lignocellulosic and other natural and synthetic fibrous materials in the manufacture of paper, paperboard, and fiberboard products. The refiner fillings include a pattern of blades and spacers defined by a bar cluster, with the bar cluster being the basis of formation of the filling. A method of manufacture provides bar cluster patterns based on factors including pumping angle, plurality of segments in a refiner filling, and the number of clusters in a segment. A bar set cluster is established for uniform fabrication of bar clusters for the refiner fillings.
3
FIELD OF THE INVENTION This invention relates to phase locked loops generally, and particularly to phase locked loops for use in applications in which a periodic component of the loop input signal may be subjected to occasional phase inversions. BACKGROUND OF THE INVENTION Phase locked loops (PLUs) are circuits well known in the communication arts for synchronizing a variable local oscillator with the phase and/or frequency of a component of a transmitted signal. Typically such circuitry includes a phase detector which is responsive to the transmitted signal and the output of a local oscillator for generating a phase error signal proportional to a difference between a component of the transmitted signal and the oscillator output. The phase error signal is subjected to smoothing and coupled to control the oscillation rate of the variable oscillator thus forming a self-regulating closed loop system. In order to enhance the operation of the PLL, some systems include a second loop which generates an error signal proportional to the difference between the frequency of the variable oscillator and the frequency of the component of the transmitted signal. The frequency error signal is added to the phase error signal for controlling the rate of the oscillator. Nominally, the variable oscillator will achieve the desired frequency before phase lock is achieved, at which time the frequency error signal is substantially zero and the PLL is controlled by only the phase error signal. An example of a frequency/phase responsive PLL is described by Canfield et al., in U.S. Pat. No. 5,159,292 entitled ADAPTIVE PHASE LOCKED LOOP. In the Canfield system an unlock detector is used to a switch in the frequency error signal path which actively disconnects the frequency error term when the system approaches phase lock. The active disconnection of the frequency term precludes noise in the frequency error signal from causing jitter in the phase of the signal provided by the variable oscillator. In order to detect the frequency unlock condition of the loop, the Canfield system includes a quadrature phase detector that accumulates samples of in-phase and quadrature components of the input signal and the unlock condition is determined by counting the number of times the accumulated in-phase samples change polarity during an interval (e.g., a field) and comparing this count value to a threshold value. In order to prevent the combined frequency and phase error signal from excessively altering the oscillator frequency when unlocked, the combined error signal is applied to a limiter before being low pass filtered and applied to the oscillator. SUMMARY OF THE INVENTION In phase locked loops generally a compromise must be made between acquisition speed, which requires a relatively short loop time constant, and steady state stability, which requires a relatively long loop time constant. In the Canfield et al. system a desirable increase in acquisiton speed is obtained without altering the loop time constant by adding the frequency error term to the phase error term when acquiring lock. The present invention is directed in one respect to meeting the need for further improvement in loop parameters including acquisiton speed and steady state stability. It has been found that phase locked loops of the general type described may exhibit substantial phase errors, or lock detection errors, or both for video input signals that contain substantial amounts of noise or that have been anti-copy protected by periodic burst phase inversions. (In one anti-copy coding system burst is inverted for 4 of each 20 lines). The present invention is directed in a second respect to meeting the need for a phase locked loop having improved stability for phase locking to the periodic component of transmitted signals which may be subjected to noisy input signals or to periodic phase inversions. Phase locked loop apparatus, for generating an oscillatory signal phase locked to a component of a further signal, and in accordance with the present invention, comprises a variable oscillator for generating the oscillatory signal and a source of the further signal. A phase detector responsive to the oscillatory signal and to the component of the further signal, provides a phase error signal which is coupled to the variable oscillator via a limiter. Circuit means are provided for controlling the limiting level of the limiter. BRIEF DESCRIPTION OF THE DRAWING The foregoing and further features of the invention are illustrated in the accompanying drawing, wherein like elements are denoted by like reference designators, and in which: FIG. 1 is a block diagram of a television apparatus including a phase locked loop embodying the invention; FIG. 2 is a detailed block diagram of an inhibitable counter suitable for use in the example of FIG. 1; FIG. 3 is a detailed block diagram of a burst sample accumulator suitable for use in the apparatus of FIG. 1; FIG. 4 is a detailed block diagram of a rectangular to polar coordinate converter suitable for use in the apparatus of FIG. 1; FIG. 5 is a detailed block diagram of a limiter suitable for use in the apparatus of FIG. 1; FIG. 6 is a phasor diagram illustrating certain aspects of operation of the example of FIG. 1; and FIG. 7 is a table illustrating operation of the rectangular to polar coordinate converter of FIG. 4; FIG. 8 is a detailed block diagram of a lock detector suitable for use in the phase locked loop of FIG. 1; FIG. 9 is a detailed logic diagram of a phase error rotation detector suitable for use in the lock detector of FIG. 8; and FIG. 10 is a detailed logic diagram of a burst phase wrap detector suitable for use in the lock detector of FIG. 8. DETAILED DESCRIPTION FIG. 1 illustrates a useful application of a phase locked loop embodying the invention in a color television receiver for measuring video signal noise levels so as to control various picture processing parameters of the receiver. Video noise detectors are of general utility in video signal processing apparatus. For example, such detectors may be used to advantage in video systems of a type which are designed to vary functionally in accordance with the level of noise of the video signal being processed. Such noise controlled apparatus include, illustratively, those having noise responsive programmable bandwidth filters, noise responsive horizontal peaking circuits, noise responsive variable saturation chrominance processors and noise reducing recursive filters, to name a few of such uses. The television apparatus 10 in FIG. 1 includes a video source 12 for providing a video signal S1 and a video signal processing and display unit 14 for displaying the video signal. For television receiver applications the source 12 may include a conventional tuner, IF amplifier and detector. Additionally, source 12 may include one or more baseband video inputs and suitable switching for selecting from plural video input signals. For television monitor applications the tuner may be omitted. The processing and display unit 14 may be of conventional design including, for example, luma and chroma processing circuits, a display (e.g., a kinescope or LCD device) and suitable display driver circuits. To simplify the drawing, details of sound and color processing are omitted. The baseband video signal S1 provided by source 12 is converted to a digital signal S2 for application to the video processing and display unit 14 by means of an analog to digital (A/D) converter 20 in a digital phase locked loop 16 (outlined in phantom) embodying the invention. The noise indicating signal (B0, B1) is applied to a control input of a picture enhancement processor 18 which is coupled to receive a video signal S3 from the display processor 14 and to supply an enhanced video signal S4 back to the display processor for display. The purpose of processor 18 is to enhance one or more parameters of the displayed image and vary the enhancement as a function of the noise level as indicated by the two-bit noise indicating signal (B0, B1). To this end the enhancement processor 18 may be of conventional design and may provide, illustratively a desirable reduction in video bandwidth as the noise level increases, or it may apply "depeaking" under poor signal to noise ratio conditions. Other exemplary functions that may be provided by processor 18 include utilization of utilizes the noise signal to control both video peaking and the chrominance signal level. Another useful application of the noise signal would be for controlling the degree of noise reduction applied to video signals. It is apparent that many other suitable applications exist for the noise level indicating signal (B0, B1). Digital phase locked loop 16 comprises the analog to digital (A/D) converter 20 to which the video signal S1 is applied and which supplies the converted (digital) video signal S2 to the processing and display unit 14 as previously mentioned. A phase locked sampling clock signal S5 of four times the color subcarrier frequency (4 Fsc) is provided to D/A converter 20, to a burst accumulator (or "quadrature phase detector") 22 and to a timing unit 24 by a voltage controlled oscillator 26. The timing unit 24 is synchronized with the "master clock" (S5) signal provided by VCO 26 and with deflection timing signals DFL from the video processing and display unit 14 for generating a number of timing signals for the phase locked loop 16 including horizontal synchronizing (HS), vertical synchronizing (VS) and burst gating (BG) signals. The burst gating signal BG, the 4 Fsc clock signal and the sampled video signal S2 are applied to the burst accumulator 22 which sorts and totalizes the even and odd samples of signal S2 occurring during the burst interval into two groups of samples. This includes an in-phase group of samples X (which occur at the burst peaks) and a quadrature phase group of samples Y (which occur at the burst zero crossings). The numbers X and Y represent the burst vector coordinates in a Cartesian (rectangular) coordinate system. An exemplary accumulator is shown in FIG. 2 and described later. The X and Y coordinates of the burst vector are next applied to a polar to rectangular coordinate converter 30 which converts the XY coordinates from rectangular to polar coordinate form (R,φ) having a magnitude term R and a phase angle term φ. A direct approach to providing this conversion would be to apply the X and Y values to the address inputs of a read only memory (ROM) programmed with the corresponding radius and angle values. Such an arrangement, however, would require a relatively large memory. A better approach, which eliminates the need for a large memory, would be to calculate the angles using sine, cosine or tangent trigonometric approximations. FIG. 3 is exemplary of such a coordinate system converter (rectangular to polar) and is discussed in detail later. The magnitude term R provided by polar converter 30 is applied to a burst detector 32 which outputs a signal S8 denoted "BLACK & WHITE" to an input of a burst phase jitter processor 40 when the video signal S1 includes no burst component thus indicating a black and white (monochrome) picture. Two further signals generated by polar converter 30 are a NO-BURST signal S6 and an OCTANT signal S7, both of which are applied to respective inputs of the jitter processor 40. The "NO-BURST" signal is generated by a second burst detector which is located in the polar converter (and shown in FIG. 4) and detects the absence of individual bursts of the video signal S2. This information is needed by the jitter processor to inhibit processing during selected lines of a color video signal. For example, burst is not present during certain lines of the vertical interval (e.g., lines 1-9 when vertical sync is present). Individual bursts may be missing also in a color video signal during active video intervals due, for example, to loss of signal from noise, magnetic tape drop-outs or the like. In brief summary, the system of FIG. 1 includes a pair of noise detectors. One of these detectors (32) is provided with a relatively long time constant or response speed (e.g., one field or more) for identifying black and white (monochrome) having no burst component at all. This detector inhibits the noise detection system for all monochrome video input signals. The other burst detector (310 in FIG. 3) is provided with a relatively short time constant or response speed (e.g., one line time) for identifying missing bursts on a line by line basis. In a color video signal some bursts are always missing, such as during lines 1-9 of the vertical interval, and some are occasionally missing, due to noise or tape dropouts. To achieve an accurate estimate of noise in a color video signal, the missing bursts are detected and used to provide a modification of operation of the jitter processor 40. As noted above, the polar converter 30 also outputs a signal called "OCTANT" to the jitter processor 40. The term octant, as used herein, means one eighth of a circle. For a circle expressed in terms of degrees, on octant would equal one eighth of 360 degrees or 45 degrees. For a circle expressed in radians, on octant would equal one eighth of two-Pi radians (e.g., Pi/4 radians). The octant signal comprises 3 bits and identifies which one of eight forty-five degree octants the burst vector angle occupies relative to the reference phase of the VCO 26. FIG. 6 illustrates the octants and the table of FIG. 7 lists the three-bit binary code identifying each 45 degree octant. As to the phase locked loop, the octant information is used in making an arctangent approximation to the burst angle as will be explained. The octant information also serves an additional purpose unrelated to the angle calculation. Specifically, the octant information also serves to inhibit processing of certain phase angles from the noise calculation. As an example, the "OCTANT" (S7) signal inhibits processing in the jitter processor 40 for burst angles in the 45 degree octant from 135 degrees to 180 degrees and in the 45 degree octant from -135 degrees to 180 degrees (Octants 3 and 7, respectively). This prevents erroneous measurements of video noise being made in the presence of certain anti-copy coded video signals. An anti-copy coded video signal is one in which portions of the video signal are intentionally altered in a way that makes video taping of the signal difficult. One such "anti-copy" system reverses the burst phasing for four of every twenty video lines. By inhibiting processing of the burst phase noise signal in the two octants adjacent to 180 degrees, the anti-copy coded burst signal is prevented from interfering with the burst jitter measurement of video noise. As to the phase locked loop itself, other measures are taken to reduce the effects of burst phase inversions as discussed in detail later. The phase angle signal φ (signal S9), produced by polar converter 30, is used for two purposes, namely, (i) for detection of noise in the video signal S1 and (ii) for phase locking VCO 26 to the burst component of the video signal S1. Specifically, phase signal φ provided by converter 30 is applied to an adder 40, to a frequency error detector 42 and to a lock detector 44. The output of the lock detector 44 is applied to a switch 46 that couples the frequency error output of detector 42 to another input of adder 40 when the lock detector indicates that the system is not locked. The frequency error detector 42 measures the rate of change of the phase signal φ from line to line and is, essentially, a differentiator and may be implemented by storing the phase of a previous line in a latch and subtracting the current and previous phase values to obtain the derivative with respect to time. Since the derivative of phase with respect to time equals frequency, the output of the frequency error detector is proportional to the frequency error when the system is not locked and is zero when locked. In the out-of-lock condition the lock detector 44 enables switch 46 to add the frequency error signal S10 to the phase angle signal S9 in adder 40. This "augmentation" of the phase angle signal when the loop is out of lock has been found to desirably enhance the speed of phase locking. Once locked however, lock detector 44 opens switch 46 removing the frequency error signal S10 from adder 40 and thereafter phase control is solely by means of the phase angle signal S9. The output of adder 40, as noted above, comprises the burst phase angle signal S9 when the system is locked (switch 46 open) and comprises the sum of S9 and the frequency error signal S10 when the system is out of lock. The adder output signal S17 is applied to a limiter circuit 50 that which provides limiting and separates the limited phase angle signal into its sign S11 (positive or negative) and its magnitude S12 (the unsigned angle) and these signals S11 and S12, respectively, are applied to a binary rate multiplier 60. The purpose of the binary rate multiplier 60 is to generate pulses of current for charging and discharging a capacitor in the loop filter 62 connected to the multiplier 60 to thereby control the frequency of oscillation of VCO 26. The number or rate of production of current pulses is proportional to the magnitude of the phase angle signal φ. For example, when the sign signal S11 is positive, binary rate multiplier 60 generates positive current pulses (signal S13) for charging the loop capacitor and increasing the VCO frequency. Conversely, when the sign signal S11 is negative, multiplier 60 generates negative current pulses (signal S14) for discharging the loop capacitor and decreasing the VCO frequency. At lock the magnitude of the phase angle φ approaches zero and only enough pulses are produced to maintain a locked condition. One reason for limiting the phase angle signal φ in limiter 50 is to prevent large phase or frequency errors from overly influencing the loop operation. A further function provided by limiter 50 is to provide an indicator signal ("LIMITING") S15 to the jitter processor 40 that indicates when the limiter 50 is in a limiting condition. The "limiting" signal thus signifies that the system is locked and that the burst phase angle is greater than a predetermined minimum or limiting value. Under these conditions the magnitude signal S12 is limited thereby limiting the maximum charge or discharge currents for the loop filter 62. An exemplary "limiting" value when the system is locked is a phase angle of about 3.5 degrees. This angle has been found sufficient narrow to prevent burst phase inversions from disturbing the phase locked loop as discussed in detail later. When out of lock, the limiting level is increased (by a factor of ten or more) to enhance the speed of re-acquiring lock. A suitable implementation of limiter 50 is shown in FIG. 5 and discussed later. The "limiting" signal S15 provided by limiter 50 is applied to the burst phase jitter processor 40. The combination of limiter 50 and processor 40, provides the function of deriving the noise indicating signal B0,B1 from the phase angle measurements provided by the polar converter 30. In more detail, recall that limiter 50 detects burst phase errors that exceed a relatively small angle (e.g., 3.5 degrees) when the system is locked. The burst phase jitter processor provides the function of counting the number of lines in a given time interval (e.g., a field or frame) for which the phase angle measurement (φ) exceeds the threshold angle of detection (3.5 degrees). From the count, the jitter processor 40 generates and outputs the count or a scaled version of it as the noise indicating signal. In this example, the count of burst phase excursions that exceed the threshold phase angle value and which occur within one field is scaled down to provide a two bit output signal (bits B0 and B1) which provide four discrete levels of noise indication (e.g., 00, 01, 10 and 11 in binary). The noise indicating signal is then applied to picture enhancement processor 18 for adjusting parameters of images displayed by unit 14 such as the contrast, sharpness, bandwidth or noise reduction as previously discussed. FIG. 2 is a detailed block diagram of a suitable implementation of processor 40. Essentially, the processor 40 comprises a non-wrapping inhibitable field-rate up-counter the output of which is scaled down to the two most significant bits (MSBs) to form the noise indicating signal B0, B1. Processor 40 includes six inputs and two outputs. Inputs 1, 2 and 3 receive, respectively the "limiting" signal S15, the "black and white" signal S8 and the "no burst" signal S6. Inputs 4 and 5 receive, respectively, the two least significant bits "1" and "0" of the octant indicating signal S7 and input 6 receives a vertical timing signal VS from the timing unit 24. The two outputs 7 and 8 provide the two bits B0 and B1 of the noise reduction signal to the picture enhancement processor 18. Processor 40 includes an up-counter 500 the output of which is divided by 16 in a divider 508 and applied to an output latch 510 that provides the noise indicating output signal bits B0 and B1. The up-counter 500 is clocked by the limiting signal S15 via inhibitable AND gate 502. Each time the limiter 50 indicates a phase angle greater than the minimum value (e.g., 3.5 degrees when locked) the counter 500 is advanced. The counter 500 is reset once each field by means of the vertical sync signal VS which also latches the counter output in latch 510. The output of counter 500 has been "scaled down" or divided by 16 in divider 508 to provide a more condensed presentation of the noise information. For example, a binary output value of "00" signifies that limiting has taken place less than 16 times during one field. An output of "01" signifies that limiting occurred at least 16 times but less than 32 times during one field. An output of "10" indicates that limiting has occurred at least 32 times but less than 48 times. Finally, an output of "11" signifies that limiting has taken place at least 48 times during a field. It has been found that scaling the count down to provide the above four indications of the number of times the burst angle (or "jitter") has exceeded the acceptable minimum phase error (e.g., about 3.5 degrees) provides a useful number of noise level indications. If finer resolution is desired one may divide the output of counter 500 by a number smaller than 16. Maximum resolution may be obtained by taking the count "C" of the counter directly as the noise indicating signal. In order to prevent the counter from "wrapping" or "overflowing" in cases where a large number of burst errors are made, the divided count is compared by a comparator 512 with a numerical value of "3" (binary "11"). This signifies that a count of 48 has been achieved in one field and the comparator output, being applied to an inhibit input (signified by an open circle) of AND gate 502, prevents further counting during the field. The foregoing prevents "false low" indications of noise. For example, suppose that a very noisy video signal clocks counter 500 beyond its modulo. The counter output then, at the end of a field, might be any number. If that number is less than 16 then the noise signal will equal "00" signifying a relatively noise free condition when, in fact, just the opposite is true. Accordingly, comparator 512 prevents "wrapping" of counter 500 and so ensures that counter 500 can not count beyond a value of "48" no matter how many limit indications are provided by the limiter 50. The foregoing discussion of the "non-wrapping" or overflow protection features of counter 500 illustrates one of four inhibiting conditions for the counter. The three other "inhibiting" conditions for counter 500 are (i) BLACK AND WHITE, (ii) NO BURST and (iii) SECTOR MASKING. Recall that monochrome video signals lack burst and so to avoid erroneous noise estimates the output of long time constant (field interval) burst detector (signal S8) which signifies that the video signal is monochrome is applied (at terminal 2) to a second inhibit input of AND gate 502. (Inhibit inputs are signified in the drawing by open circles at the gate inputs). The NO BURST signal S6 provided by a short time constant burst detector is also applied at input terminal 3 to another inhibit input of AND gate 502 to prevent counting during the vertical sync interval (when burst is absent) and to prevent counting otherwise defective bursts (e.g., burst missing due to tape oxide dropouts, etc.) with otherwise could yield an inaccurate count. The last inhibiting condition of the counter 500 is applied for burst angles within a sector extending 45 degrees on either side of 180 degrees which corresponds to octants 3 and 7 (shown in FIG. 6) of the burst phase angle. This is referred to in the drawing as "sector masking" and its purpose, as previously explained, is to exclude all bursts from being counted which are likely to be intentionally reversed in phase by anti-copying video coding techniques. As previously noted, one such technique reverses burst phase for 4 of each 20 video lines. Excluding the reverse phased lines from the measurement preserves the integrity of the noise estimate. The "sector mask" 504 (outlined in phantom) comprises a two input AND gate 506 which receives the two least significant bits ("1" and "0") of the octant signal S7. The complete octant code is shown in FIG. 7. This code identifies the sectors shown in FIG. 6 and determines the arithmetic processing used in the polar converter 30 for converting the quadrature samples X and Y into polar coordinates R and φ. As seen from the code table, to cover a sector of 180 degrees plus or minus 45 degrees, one needs only to inhibit the counter 500 during two octants, namely octant 3 and octant 7. As is apparent from the three bit binary code table, the least significant two bits of octants 3 and 7 are both logic "ones". Thus by ANDing the least significant bits of the octant code, the gate 506 will be enabled any time the octant code is either "3" (011 in binary) or "7" (111 in binary). The output of gate 506 is therefore connected to an inhibit input of the gate 502 whereby counting is inhibited whenever the burst phase angle is in the "excluded" sector (octants 3 or 7). FIG. 3 is a detailed logic diagram of a suitable implementation of the burst accumulator (or quadrature phase detector) 22 of FIG. 1. Reviewing briefly, the function of the accumulator is to sample burst at four times the color subcarrier frequency (4 Fsc) thus producing one sample for each 90 degrees of the burst signal. When the loop is locked, the even samples occur at the peaks of the burst thus forming the "in-phase" or "X" samples and the odd samples occur at axis crossings of burst to form the "quadrature phase" or "Y" samples. Taken together, these two values, X and Y represent the burst vector in a rectangular coordinate system. The function of the accumulator 22 is to perform the necessary arithmetic operations for properly sorting and totalizing the samples including removal of the direct current (DC) component or "pedestal" value (e.g., around black level) from the burst samples produced by the A/D converter 20. In more detail, the video signal samples produced by A/D converter 20 are in the form of unsigned binary. Since burst appears during the trailing portion of horizontal sync, it will have a DC or pedestal value around black level. The exact value may be unknown or may vary with the signal source. To remove this component from the burst measurements, the video signal S2 from A/D converter 20 is first converted from unsigned binary to a two's complement form by inverting the most significant bit (MSB) by means of an inverter 300. This change in arithmetic form facilitates addition and subtraction of samples in the accumulator. The two's complement samples from the inverter 300 are next applied to an adder/subtractor 302 comprising an exclusive OR gate 304 and a full adder 306. Selection of addition or subtraction modes is controlled by a clock signal Fsc at the color subcarrier rate which is one fourth of the 4-Fsc clock rate of the VCO 26. The adder/subtractor output is stored in two series connected latches 312 and 314 and fed back to the adder addend input. By clocking the latches at the 4 Fsc sample rate and changing from addition to subtraction every two sample periods using the Fsc clock, the in-phase samples "X" will be accumulated in latch 312 and the quadrature phase samples "Y" will be accumulated in latch 314. Since the adder/subtractor alternates between addition and subtraction every two sample periods of the 4 Fsc clock, the "X" samples are alternately added and subtracted to produce the accumulated "X" value in latch 312. It is the alternate addition and subtraction of the X value samples (e.g., +X0,-X2, +X4,.increment.X6, +X8,-X10 etc.) which results in cancellation of the DC component of X. The burst component of X does not cancel because the burst "sign" or polarity alternates every two samples and so the burst samples add. Accordingly, the burst samples accumulate and the DC component or pedestal portion of the samples simply cancel. The same result occurs for the Y samples. To confine the X and Y samples to burst only, the output of adder 306 (a 13 bit sum) is applied to the accumulator latch 312 via a burst gate 310 which is enabled for 48 of the 4-Fsc clock periods during the burst interval of each line. A typical burst (NTSC) will have 8 complete cycles corresponding to 32 samples of the 4-Fsc clock. The burst gate is intentionally made substantially wider than the burst width to ensure capture of all the burst cycles in the event of substantial timing errors in the video source. At the end of the burst gating period (48 samples of the 4-Fsc clock) a burst gate closed signal (provided by timing unit 24) is applied to latches 316 and 318 which store the accumulated burst vector data X and Y for the remainder of the line during which time the data is converted to polar form, passed through limiter 50 and the noise estimate is made by counting the number of times the limiter limit is exceeded as previously explained. FIG. 4 is a detailed logic diagram illustrating the polar converter 30 which provides the functions of: (i) conversion from rectangular to polar coordinate form (magnitude and angle) for the burst vector, (ii) identification of the specific octant the burst vector is in and (iii) generation of the "NO BURST" signal. To provide polar conversion, the X and Y coordinates from accumulator 22 are applied to respective inputs of a comparison and division circuit 410 via respective one's complemenator circuits each comprising a ones complementor or inverter (400 or 403) and a multiplex switch (402 or 404) controlled by the sign bit of the input signal. This converts the coordinates from two's complement to unsigned binary for ease of subsequent magnitude comparisons and division. For example, when the sign of X is "0" (bit 13, indicating a positive number), the remaining 12 bits of the magnitude of X are passed directly to the X input of circuit 410 via mux 402. If, however, the sign of X is negative (binary "1", indicating a negative number), then mux switch 402 couples the complemented 12 magnitude bits to the X input of circuit 410 thus converting X to unsigned binary form. The magnitude bits (e.g., 1-12) of the Y input signal are similarly converted to unsigned form under control of the Y sign bit (bit 13) for application to the Y input of the comparison and division circuit 410. Internally, the compare and divide circuit 410 includes a magnitude comparator for identifying the larger of X and Y and outputs this value as signal "L" (i.e., "larger"). The signal "L" is used to represent the "MAGNITUDE" of the polar burst vector S12 for application to the burst detector 30. The polar magnitude signal "L" is also applied to a short time constant NO-BURST detector comprising a comparator 432 which compares signal "L" with a reference level signal provided by a NO BURST threshold source 436. For purposes of overall system adjustment, the threshold source 436 is programmable to provide a number of reference values. Illustratively, burst reference values of 16, 32, 64 and 128 are available. In terms of IRE signal levels, these correspond to burst amplitudes of 1, 2, 4 and 8 IRE levels. The comparator compares signal "L", (which is the "larger" of the vector components X and Y), with the burst reference level provided by source 436 and outputs the NO-BURST signal S6 when the magnitude signal "L" is less than the burst reference signal R. As previously noted, the time constant of this burst detector is relatively short in that detection occurs on a line by line basis as compared with the long time constant burst detector 32 which has a field rate time constant for detecting monochrome video signals. The NO-BURST signal S6, as previously noted, inhibits the calculation of the video noise level for lines with burst missing such as the lines of vertical sync and lines with burst drop outs. Identification of specific octants of the burst vector is provided by a three bit octant identifications signal S7. The most significant bit comprises the sign bit of the "Y" input signal. The second most significant bit B1 comprises the sign bit of the "X" input signal. The lease significant bit LSB comprises the exclusive OR of the sign bit of the "X" input signal with the output of the X<Y magnitude comparator in circuit 410. FIG. 7, as previously noted, identifies the octants 0-7 in terms of this three bit code. Reviewing briefly, the lower two bits of the octant code are AND'ed in sector mask 504 to exclude bursts from the noise calculation near 180 degrees (+/-45 degrees) to prevent errors from video material from anti-copy protected tapes of the type in which burst is periodically inverted. Considering now the details of the polar conversion function of converter 30, this conversion is based on an approximation that for small angles (e.g., below 45 degrees) the arctangent of the angle defined by the rectangular coordinates X and Y is approximately equal to the smaller of X and Y divided by the larger of X and Y. Circuit 410 includes a magnitude detector, as previously explained, which determines the relative sizes of X and Y. This detector is used internally to perform a division of the smaller of the larger signal (signified as "S/L") and this number is used to represent the 7 least significant bits of the polar angle which cover a range of 45 degrees. To cover a full circle (360 degrees) the converter 30 adds or subtracts angles of 0, 90, or 180 degrees depending upon the octant the burst vector is in. The octants are determined as described above and the arithmetic of deriving the full value for each octant is shown in FIG. 7. In more detail, the arithmetic calculations of FIG. 7 for the burst vector angle are performed in converter 30 by a full adder 420 which by means of exclusive OR gate 414 and inverter 422 is capable of either addition or subtraction. Two multiplex switches are provided 416 and 418 which provide the numerical equivalent of fixed angles of 0, 90 and 180 degrees to one input of the adder 420. By selecting the appropriate fixed angle, and arithmetically combining (e.g., adding or subtracting) it with the arctangent approximation of the burst angle (the signal S/L), any burst angle in octants 0-3 can be represented. The remaining octants 4-7 are calculated by inverting the corresponding one of the octants 0-3. This is done by the exclusive OR gate 428 connected to the output of adder 420. As an example of calculation of the burst angle, assume that the vectors X and Y are both positive and X is larger than Y. This defines a burst vector in octant "0" which lies between zero and forty five degrees and whose angular value is approximately equal to Y/X (the smaller divided by the larger). Since X is positive, the multiplex switch 416 will select the constant "zero" as an output which corresponds to zero angular degrees. Since it is assumed that X is larger than Y the comparator signal X<Y will also be zero thus causing multiplex switch 418 to select the output of switch 416 which is zero degrees, as previously noted. Adder 420, for this condition adds a constant of zero (from switches 416 and 418) to the arctangent approximation (S/L) from compare and divide circuit 410 and since the sign of Y is zero (Y is positive) the output exclusive OR gate 428 will pass this value (+S/L) as the burst phase angle S9. For different octants adder 420 adds different constants to S/L as shown in the inset dashed circle at the adder output and shown also in the table of FIG. 7. For example, for a burst vector lying in octant 1, the complete vector angle is the value of S/L subtracted from the 90 degree reference provided by switch 416. In octant 2 the 90 degree value is added to the S/L value and in octant 3 the burst vector is determined by subtracting the S/L value from 180 degrees. For the remaining octants 4-7, the value of the burst vector is found exactly as for the corresponding octants 0-3 except that the output of the adder 420 is inverted by exclusive OR gate 428 thus reversing the sign of the indicated burst phase angle. FIG. 5 is a detailed logic diagram of the limiter 50. This unit converts the burst vector error signal (i.e., the phase plus frequency signal S17) into sign and magnitude format and provides dual mode limiting action. It limits the error signal magnitude to "7" when the system is locked and to a level of "127" when the system is unlocked. The binary values of 7 and 127 correspond, in terms of burst phase angular degrees to about 3.5 degrees and 63 degrees, respectively. Advantageously, providing a wider range of burst phase error angles before limiting is reached for the unlocked condition provides further enhancement in lock acquisition speed in addition to the speed enhancement provided by the frequency term (S10) that is added to the phase term (S9) by adder 40 when the loop is in the unlocked condition. Conversely, the narrow range of 3.5 degrees has been found to be effective in counteracting the undesirable effects of burst phase inversions as discussed in detail later. In limiter 50 the phase plus frequency signal S17 from adder 40 is converted from two's complement form to unsigned binary by means of a ones' complementor 502 and a multiplex switch 504. The switch 504 is controlled by the sign bit of the input signal to select the 14 magnitude bits as an output (S50) when the sign bit is zero (indicating a positive number) and to select the output of the ones complementor 502 when the sign bit is "1" (signifying a negative number) thus producing an unsigned binary output signal S50. The sign bit of the input signal (bit 15) is also stored in a latch 510 so as to provide the sign bit signal S11 for use by the binary rate multiplier in determining the polarity of output current (current 18 or current sinking) to the loop filter. The unsigned binary phase angle signal S50 is applied to a comparator 508 which a multiplex switch 512 to select the seven least significant bits of signal S50 (provided by a truncator 605) when signal S50 is greater than a value of "127", otherwise, switch 512 selects a constant "high limit" value of "127" as the output. This portion of the circuit thus provides a first level of limiting of the burst phase angle signal to a level of "127". If, for example, the burst phase angle is any value less than 127, then comparator 508 will select the truncated signal S54 as the output signal S56 of switch 512. Conversely, any value of burst angle greater than 127 will cause switch 512 to select the reference value of "127" as the output signal S56. A second stage of limiting of the signal S56 is provided by a comparator 514, an inhibit AND gate 516 and a second multiplex switch 518. Specifically, comparator 514 compares the burst angle signal S56 with a reference level of "7" and provides a high output if signal S56 is greater than the value of 7. The gate 516 receives the output of comparator 514 and is enabled by lock detector 44 when the lock detector output is low signifying an "locked" condition of the loop. If the input signal S56 is less than a value of "7", and the loop is locked, then switch 518 will select the signal S56 as the burst phase angle. If the input signal is greater than 7, and the loop is locked, gate 516 will cause switch 518 to select a fixed limiting value of "7" as an output thus limiting the burst phase angle to about 3.5 degrees which the loop is locked. However, if the loop is unlocked, gate 516 will cause switch 518 to select the signal S56 (which has a limiting level of 127) as the output burst vector angle. A latch 520 is provided for storing the burst vector angle signal S12. Reviewing briefly, the gate 516 provides the "limiting" output signal S15 for processor 40. This signal will be high if the loop is locked and the burst angle is greater than the reference value of "7" which corresponds to a burst phase angle of about 3.5 degrees. The "limiting" output signal will be low if the loop is not locked or if the burst phase angle error is below the limiting value of "7" which corresponds approximately, to a burst phase error of 3.5 degrees. Processor 40, as previously explained, tallies the number of times limiting has taken place when the loop is locked for developing the video noise level indicating signal (B0,B1). FIG. 8 is a detailed block diagram of the lock detector 44 which controls the limiting levels or the "phase angle window" of the limiter 50. Recall that limiter 50 has two operating modes. When unlocked, the limiting level corresponds to burst phase error limits of plus or minus about 60 degrees. This relatively wide range facilitates rapid lock acquisition by effectively decreasing the loop time constant. The acquisition of lock is further enhanced when the limiter reduces the loop time constant the lock detector also closes switch 46 which adds the frequency term S10 to the phase term S9. When locked, the detector 44 disables the frequency term by opening switch 44 and concurrently reduces the limiting level to the range of plus or minus 3.5 degrees thus substantially increasing the loop time constant. This range is quite narrow and has been found to be effective in reducing noise and in limiting the effect of the inverted bursts used in anti-copy coding. Stated another way, when lock is established loop time constant is increased and there is no signal that can produce a transient change in the burst error vector beyond 3.5 degrees. As a result, phase angle errors beyond 3.5 degrees have little effect on the operation of the VCO 26 and the oscillator output remains stable in the presence of noise or burst inversions. The circuit which controls the width or "aperture" of the "phase angle window" comprises the lock detector 44. This circuit is also provided with protection against inverted bursts. Briefly stated, this added inverted burst protection is achieved by the combination of (i) testing the phase error vector (signal S17) for phase rotation and (ii) restricting the angles for the rotation test to phase angles that the anti-copy coding never uses, namely, plus and minus 90 degrees or windows centered with respect to the vertical axis of the phase error plane (e.g., the Y axis in FIG. 6). Recall that in the prior art lock detector operated by counting the number of times accumulated in-phase samples change polarity during a field and comparing the count to a threshold value. Such an approach to lock detection has been found to be susceptible to anti-copy reverse phase bursts with the result that the lock detector can erroneously produce a false "out of lock" signal which, if not prevented, could open the aperture or window discussed above and thus produce a large VCO transient. In turn, the transient may actually cause the loop to lose phase lock. Such false "out of lock" detections are avoided in detector 44 by testing for phase error vector rotation rather than counting sign reversals of the in-phase component as in the prior art example. Additional rejection of false out of lock indications is provided by restricting the rotation test to zones or angles that inverted bursts do not occupy. A further feature of detector 44 in FIG. 8 also relates to minimization of false "out of lock" indications due not to inverted bursts but rather to the mechanics of arithmetic processing. This feature is called burst phase error "wrap" detection and is implemented in a detector 804 by examination of the left half plane of the phase error plane (see FIG. 6) to determine if the phase error vector has passed from +180 degrees to -180 degrees or vice versa. This is called phase "wrapping" because it represents a phase change in excess of the angular range of the polar converter 30 which provides polar conversions over a range of 360 degrees from -180 to +180 degrees. Stated another way, phase error changes beyond 180 degrees will "wrap" around the phase plane limits and thus may introduce false phase error indications. (The wrapping effect is somewhat like forcing a counter to count beyond its modulo so that the count passes its maximum and "wraps" around to begin counting at zero.) Phase wrapping effects in the lock detector 44 may occur, however, they are prevented from disturbing the loop by detecting when a wrap has occurred and immediately sending a "phase locked" signal to the limiter 50. By this means, the maximum disturbance to the overall loop is limited to the lowest limiting level of the limiter 50 which is about 3.5 degrees. If the phase wrapping feature of lock detector is omitted, the maximum phase error due to wrapping is the highest limiting level of the limiter 50 which, in this example, is 60 degrees. Now considering the details of FIG. 8, the burst phase angle data from polar converter 30 is applied via bus 802 to a burst phase wrap decoder 804, to an N-bit data latch 806 (which, as shown, is updated by the horizontal synchronizing signal HS at the horizontal line rate) and to a burst phase rotating detector 808. As previously noted the burst phase data may comprise a full (13 bit) binary word representing the phase error vector angle (signal S9) to high resolution. If so, the bus 802 would be connected to the signal S9 output of converter 30 as indicated by the dashed line 101 in FIG. 1 and the N-bit latch 806 would have a 13 bit capacity. However, such high high precision (13 bits) is not necessary for the purposes of detecting wrapping or rotation and so the lower resolution octant representations of the phase angle are used in the lock detector 44. For selecting octant phase angle data, the input bus 802 is connected to the octant signal output (S6) of converter 30, as indicated by the solid line 100 in FIG. 1. For octant data the N-bit data latch 806 only requires a 3-bit storage capacity since only 3 bits are required to identify all eight octants as shown in FIG. 7. Using the octant data desirably simplifies the hardware required for implementing the burst phase wrap detector, the N-bit latch and the burst phase rotating detector. The burst phase wrap and rotation detectors both require phase information from the current and previous lines. The bus 802 provides the current phase error angle (octant in this case) data from polar converter 30. The phase information from the previous line is provided by latch 806 which stores the burst angle or octant of the previous line and this data is provided to the decoders 804 and 808 via data bus 810. The burst phase rotating decoder 808 compares the current burst phase angle on bus 802 with that of the previous line on bus 810 and determines if the burst error vector is rotating in either the clockwise direction or the counter-clockwise direction. Rotation of the burst error phase may be used to indicate an unlocked condition of the loop if one selects some particular octants or angles. For example, one can not test the burst error vector at an angle of zero degrees for rotation since the vector will normally be in the vicinity of zero degrees when the loop is locked and thus would appear to be rotating almost all the time. It is recognized herein that the burst error vector can not be tested either for rotation at an angle of 180 degrees since that angle is within the expected range of bursts which have been inverted by the aforementioned anti-copy coding system. To avoid detection errors due to burst phase inversions, the rotation test is made in detector 808 only for burst angles in the vicinity of plus or minus 90 degrees. In terms of octants, this corresponds to burst phase angles passing from octant 1 to octant 2 and vice versa, and to burst angles passing from octant 5 to octant 6 and vice versa. This restriction to detection of rotation near angles of plus or minus 90 degrees, to the exclusion of angles near zero and 180 degrees provides a further degree of protection for the loop from disturbances by anti-copy coding of the type employing periodic burst inversion. This protection is in addition to that provided by the very narrow phase error window of plus or minus 3.5 degrees which is provided by the limiter 50 when in the narrow range limiting mode. Logic suitable for implementing the phase rotating detector, using octant angular data, is shown in FIG. 9. As shown, the octant data from the current and previous fields is decoded in decoders 902 and 904. The AND gate 906 determines clockwise vector rotation across the angle +90 degrees by determining if the current octant is "1" and the previous octant (from decoder 904) was "2". The AND gate 910 determines counter-clockwise rotation at +90 degrees by determining if the current octant is "2" and the previous octant was "1". In a similar fashion, AND gates 908 and 912 determine rotation about the -90 degree axis and the outputs of all of the AND gates are combined in a four input OR gate 914. This output will be high if any AND gate output is high thereby signifying that rotation has occurred for burst phase errors near 90 degrees or -90 degrees in either clockwise or counter-clockwise directions. Returning to FIG. 8, if phase rotation is detected by decoder 808, it is an indication that the oscillator and burst frequencies are different and so the loop is in an unlocked condition. The phase rotation signal (R1) could be used directly for controlling the limiting levels of limiter 50. However, a "false" unlock indication from the lock detector can have very undesirable consequences. Specifically, false unlock indications concurrently raise the limiting level to an angle of 60 degrees and closes switch 46 which adds the frequency error term to the phase error term. The effect is that a transient may be produced and, worse still, the transient may be large enough to unlock a loop that previously was locked, all because of a "false" indication that the loop was unlocked to start with. To minimize the possibility of false unlock indications due to erroneous indications of phase rotation, the phase rotating signal R1 from decoder 808 is applied to a non-wrapping, modulo 4 counter which requires that 4 rotation detections occur within one field to generate an output phase rotating signal R2. This substantially increases the degree of confidence for detector 44 that the phase rotations are valid. The phase error rotation counter comprises AND gate that passes the phase rotation signal R1 to the enable or clock input of a modulo four up counter 814 that is reset by the vertical signal VS once each field. If the up counter 814 count "C" equals four counts, decoder 816 will supply an inhibit or "non-wrap" signal to gate 812 that stops the counter from counting any more rotation pulses. This prevents the counter from "wrapping" or exceeding its modulo (4) which otherwise could give erroneous results. Gate 812 is also inhibited by the "no burst" signal from converter 30 to prevent possibly erroneous rotation indications when burst is absent from being counted. Gate 812 is synchronized for clocking counter 814 by means of a line rate (horizontal synchronizing) pulse HS and is inhibited during the vertical interval by means of the vertical synchronizing signal VS. The output of decoder 816 will be high if 4 rotations have occurred during a field thus signifying an out of lock condition and will be low otherwise. The rotation signal (R2), with a confidence level enhanced by counting rotations per field, is stored in a latch 818 at the end of each field by means of the vertical signal VS and is coupled to the limiter 50 via AND gate 820. When R2 indicates an out of lock condition, and the burst phase wrap signal applied to an inhibit input of gate 820 is low, the limiter 50 range is increased from plus or minus 3.5 degrees to plus or minus about 60 degrees and the frequency term S10 is added to the phase error term S9 thus enabling rapid re-locking. Conversely, if either the burst phase wrap signal is high or if the phase rotating signal is low, the gate 820 will reduce the limiting level of limiter 50 to 3.5 degrees and disable the frequency error term. Considering now the details of the burst phase wrap decoder 804, recall that the function of this circuit is to force the output of the lock detector 44 to a "locked" indication whenever the burst phase error vector passes from +180 to -180 degrees or vice versa. One may make this determination by comparing the current and previous phase angles using the full (13 bit) resolution of the polar converter 30. A better way is to divide the phase error plane into octants to determine if wrapping has occurred because the logic is much less complex. The logic, using octants to represent the phase angles, is defined by the following conditions: 1. The current octant is in the left half plane; and 2. the current octant and the previous octant are in opposite upper and lower half-planes. FIG. 10 illustrates one way of implementing the decoding logic for detecting burst phase error wrap. In FIG. 10 the current and previous 3-bit binary octant data from bus 802 and bus 810 is decoded to decimal form by respective decoders 1002 and 1004. Condition (1) referred to above is determined by an OR gate 1006 which is connected to the 2, 3, 6, and 7 octant outputs of decoder 1002. From FIG. 6, these octants are all of the octants in the left half-plane and so the output of OR gate 1006 will be high if the vector is anywhere in the left half-plane. Condition (2) of the phase wrap logic decoder is detected by two OR gates 1008 and 1012 and an exclusive NOR gate 1020. Gate 1008 is enabled to produce a high output if the current octant is in any one of octants 0, 1, 2, and 3. These are all of the upper half-plane so a high output of gate 1008 signifies if the current octant is in the upper half-plane. Gate 1012 performs a similar function for the previous octant. Specifically, if the previous burst phase error vector was in the upper half plane, then the output of OR gate 1012 will go high. An EXCLUSIVE-NOR gate 1020 combines the outputs of gates 1008 and 1012. If the previous and the current octants were in the upper half plane, OR if neither of the previous and current octants were in the upper half-plane, then the output,of the EX-NOR gate 1020 will be low. Accordingly, the output will be high if the current octant and the previous octant are in opposite upper and lower half-planes. This satisfies condition (2) above. A combined output signal is provided by AND gate 1022 which receives the outputs of OR gate 1006 and EX-NOR gate 1020 and provides a high output signal signifying a burst phase wrap condition when both of conditions (1) and (2) are satisfied. Stated another way, gate 1022 will produce a high output signal if the burst phase error vector passes in either direction past 180 degrees. As previously noted, this wrap condition forces the output of gate 820 low signifying a locked condition which forces the limiter level to its narrow value (3.5 degrees) and disables the frequency error term.
PLL apparatus for generating an oscillatory signal phase locked to a component of a further signal comprises a variable oscillator for generating the oscillatory signal and a source of the further signal. A phase detector responsive to the oscillatory signal and to the component of the further signal, provides a phase error signal which is coupled to the variable oscillator via a limiter. Circuit means are provided for controlling the limiting level of the limiter. The dual limiting substantially improves the loop noise tolerance and reduces the loop sensitivity to occasional phase reversals of the component of the further signal. Additional enhancements to loop stability and noise immunity are provided by an unlock detector which detects and totalizes phase rotations in a selected area of a phase plane and by a phase wrap detector which maintains a lock indication during phase angle wrapping.
8
The automatic retractable hatch guard provides enhanced safety and security to hatch openings in roofs and other walking/working surfaces. The hatch guard can also facilitate hatch conditions that meet or exceed safety standards described by various agencies and industries, for example, safety standards prescribed by the U.S. Occupational Safety and Health Administration (OSHA), standards recommended by the National Roofing Contractors Association (NRCA), and various other interested parties. Passage through a hatch opening is recognized to be a safety concern. A worker ascending a ladder to a closed hatch can be required to release the ladder with one or both hands in order to unlock and unlatch the hatch cover. It is not uncommon for the worker to have to turn to face away from the ladder to access a hatch cover latch. Furthermore, transitioning from the ladder to a roof surface 63 can require lying over a hatch lip 52 in order to swing the legs and body onto the roof. Similarly, moving through the hatch from the roof to the ladder can require dangling the legs blindly through the hatch opening to reach for the ladder. The hatch guard can address both the abovementioned situations by providing connecting handrails from the ladder below the hatch to the surface above the hatch. Additionally, the hatch guard can provide a solid, stable, access step above the hatch opening that can enable a worker to turn to face the ladder below as the worker transitions from the surface above to the ladder below. The hatch guard can be configured with an extended position where the handrails and the access step extend to provide the safety improvements mentioned above, and a retracted position where the hatch guard handrails and step retract to fit within the hatch opening underneath the hatch cover. In the retracted position, the hatch guard can provide the supplementary function of limiting access through the hatch opening, both from the ladder below and from the surface above. The hatch guard can be configured to move between the extended position and the retracted position in concert with opening and closing a hatch cover. As such, the hatch guard provides improved safety features automatically as needed, and provides improved security features also automatically. FIGURES FIG. 1 is an isometric view of an embodiment of the hatch guard with handrails and an access step extended. FIG. 2 is an isometric view of the embodiment with the handrails and the access step partially retracted. FIG. 3 is an isometric view of the embodiment with the handrails and the access step fully retracted. FIG. 4 is a bottom view of the embodiment. FIG. 5 is a detail view within line 5 - 5 that shows miter gears for extending and retracting the handrails. FIG. 6 is a side section view of the embodiment in place on a hatch. DETAILED DESCRIPTION OF THE INVENTION The hatch guard can comprise assistive handrails, such as the assistive handrail 11 , which extend upwards and outwards from a hatch to provide hand holds for workers as they enter and exit through the hatch. The handrails 11 , when extended, can be positioned oppositely across the treads of a ladder 41 below the hatch. The handrails 11 can extend upwards a distance from the hatch opening to enable a worker to pass through the hatch in a substantially vertical stance. The handrails 11 can provide a secure hand hold to facilitate a worker turning to face the ladder 41 when preparing to descend. Similarly, the handrails 11 can provide a secure hand hold to facilitate a worker stepping from the ladder 41 below up to the surface above. The hatch guard can further comprise an access step 12 that extends up and over a hatch lip 52 to provide a stable transition platform for the worker when moving from the ladder 41 below the hatch to the surface above, and from the surface above to the ladder 41 below. The access step 12 , when extended, can be positioned above the hatch lip 52 and can span at least part of the distance between the handrails 11 . The access step 12 can protect the hatch lip 52 from abrasion and other damage resulting from workers stepping onto the lip 52 as they move back and forth between the upper surface and the ladder 41 below. The access step 12 can provide a stable platform at a predictable height with respect to the hatch lip 52 to facilitate the worker turning to descend the ladder 41 as well as emerging to the surface from the ladder 41 . In the embodiment 10 , shown in the FIGS. 1-6 , the handrails 11 rotate about two axes simultaneously as they extend and retract. The primary axis 21 extends across the hatch opening 53 and the handrails 11 rotate about the primary axis 21 to move in and out of the hatch opening 53 . The secondary axis 22 is perpendicular to the primary axis 21 and rotates about the primary axis 21 along with the handrails 11 . The handrails 11 each rotate about respective secondary axes 22 to cover and to expose the hatch opening 53 as the handrails 11 move in and out, respectively, of the hatch opening 53 . The embodiment 10 comprises mechanical means, such as miter gears 31 , 32 , to move the handrails 11 about the primary and secondary axes, simultaneously. In the embodiment 10 , the handrails 11 and the access step 12 can be driven by a single motor 14 . Alternatively, the handrails 11 and the access step 12 can be separately driven by multiple motors, can be moved by linear actuators and by rotary actuators. The hatch guard can move between the extended position and the retracted position via various mechanisms and modes. An embodiment of the hatch guard can be configured to be remotely-operated, for example, to extend and retract in response to remote signals. Remote operation provides further safety and security enhancement. Utilizing the remotely-operated embodiment, a worker can cause the hatch guard to extend and retract the handrails and the access step from a secure position on the walking/working surface, from a position on a lower floor, and from various positions distal to the hatch. The remote signals can comprise mechanical signals, for example, a cranking signal from an elongated hand crank and a rotating signal from a chain/pulley assembly. The remote signals can comprise various other mechanical signals and combinations of mechanical signals. The remote signals can comprise transmitted signals from a hatch guard controller. The transmitted signals can be various point-to-point and broadcast transmission forms such as wireless and via wires, cables, and fibers. The hatch guard can comprise additional safety and security components. For example, the hatch guard can comprise a hatch opening light. The hatch opening light can be activated by the hatch guard extending and retracting. The hatch opening can be activated by a remote signal. Additionally, the hatch guard can comprise an interior smoke detector and an exterior smoke detector, for sampling the environment inside the hatch and outside the hatch, respectively. Similarly, the hatch guard can comprise an interior dangerous-gas sensor and an exterior dangerous-gas sensor. The smoke detectors and the dangerous-gas sensors can activate audible and visual alarms to alert workers to the presence of the sensed elements. The hatch guard can comprise a hatch guard controller having a processor, where the controller via the processor causes the hatch guard to extend and retract. The controller, via the processor, can respond to commands according to programmable instructions. The controller, via the processor, can respond in various ways to commands according to the programmable instructions. The controller can further comprise a data storage component for storing data, including data in the form of programmable instructions. The controller can be programmable so that executable commands can be input to the controller and so that executable commands can be edited and deleted from the processor. The controller can store data including historical data and the controller can cause the hatch guard to respond according to the historical data. The controller can respond to remote signals to cause the hatch guard to extend and retract. The controller can respond to The hatch guard controller can comprise a hatch cover manager as described in U.S. Pat. No. 7,638,962, issue date Dec. 29, 2009, which is incorporated by reference herein in its entirety. An embodiment of the hatch guard can comprise a hatch opening mechanism. The hatch opening mechanism can open and close a hatch cover 51 cooperatively with extending and retracting the handrails and access step. The hatch opening mechanism can be separately driven by a motor, can be driven by a motor shared with other hatch guard components, and can be driven by a linear actuator, a rotary actuator, and various mechanical means and combinations thereof. The embodiment so configured can comprise the aforementioned hatch cover manager and can respond to the opening and closing of the hatch cover 51 where the hatch cover 51 is controlled by the hatch cover manager. The hatch guard can be controlled by the hatch cover manager so that the hatch guard responds to various conditions as described in U.S. Pat. No. 7,638,962. The hatch guard can comprise a fixed step 42 positioned below the access step 12 when the access step 12 is extended. The fixed step 42 can provide a predetermined step height between the access step 12 and the fixed step 42 . Transitioning from a ladder 41 below, whether the ladder 41 is fixed or temporary, to the surface above can cause uncertainty when the distance from the ladder (and the top step of the ladder) to the surface can vary from hatch to hatch. The fixed step 42 can augment worker safety by minimizing uncertainty regarding the step height between the access step 12 and a first step below the hatch lip. The fixed step can be integral to the hatch guard and can be a separate hatch guard component that is attached to the building structure. The hatch guard can comprise a standalone unit suitable for retrofit installation on an existing hatch. The hatch guard can comprise a sub-unit of a commercially-available hatch assembly, where some of the hatch guard functions are integrated with the common hatch operations. The hatch guard can comprise a sub-unit of a hatch cover manager as described in U.S. Pat. No. 7,638,962, where hatch guard functions are at least partly integrated with the hatch cover manager functions and where at least some hatch guard functions are controlled the hatch cover manager controller. The hatch guard can be hardwired to an electric grid to provide power for electric components. Alternatively, the hatch guard can comprise a battery to provide power. Alternatively, the hatch guard can comprise a generator to provide power. Alternatively, the hatch guard can comprise photovoltaic cells to provide power. Alternatively, the hatch guard can comprise various power sources and combinations thereof, including combinations of the aforementioned.
An automatic retractable hatch guard provides enhanced safety and security to hatch openings and comprises retractable assistive handrails and a retractable access step that retracts to fit within a hatch opening and beneath a hatch cover and automatically extends upwards and beyond the hatch opening.
4
BACKGROUND OF THE INVENTION The invention relates to a new compound of a calcium trisulfoaluminate base and also to a process for its manufacture. The manufacture of ettringite (calcium trisulfoaluminate) starting with aluminum sulfate is already known. In the French Pat. No. 72/40,247, applied for by the applicants on Nov. 13, 1972, there is described a process for the manufacture of a fine, white charge for industry, as well as the ettringite essentially obtained by the process. In accordance with the cited patent, the process for the preparation of the ettringite or calcium trisulfoaluminate (3 CaO. Al 2 O 3 . 3 CaSO 4 . 32 H 2 O) is characterized by the simultaneous hydration of a mixture of an accurate stoichiometric composition at a temperature from about 20° to about 90° C of calcium aluminate, calcium sulfate which is as white as possible, and water in at least a quantity for a stoichiometric proportion for the reaction and at the maximum such that after the reaction, a product containing 5% by weight of ettringite (in dry form) and 95% (by weight of water), is obtained, the stoichiometry being defined by at least one of the following reactions: ______________________________________CaO. Al.sub.2 O.sub.3 + 2(CaO. H.sub.2 O) + 3(CaSO.sub.4. 2 H.sub.2O)→(CaO).sub.3 Al.sub.2 O.sub.3. 3CaSO.sub.4. 32H.sub.2 O(ettringite)(CaO).sub.3 Al.sub.2 O.sub.3 + 3(CaSO.sub.4. 2H.sub.2 O) + 26 H.sub.2 O→1 ettringiteCaO. (Al.sub.2 O.sub.3).sub.2 + 5(CaO. H.sub.2 O) + 6(CaSO.sub.4.2H.sub.2 O) + 47 H.sub.2 O →2 ettringite(CaO).sub.12.(Al.sub.2 O.sub.3).sub.7 + 9(CaO. H.sub.2 O)+ 21(CaSO.sub.4. 2H.sub.2 O) + 173 H.sub.2 O→7 ettringite.______________________________________ The obtained charge principally consists of ettringite (calcium trisulfoaluminate). It is indicated in the above mentioned patent, that the process described there does not only allow the production of all forms such as dry powder, solutions, or suspensions of concentrations or contents, practically variable at will, but also allows the utilization, as the starting materials, of different industrial compounds such as, for example, aluminous cements, unburnt cements, calcium sulfates, as well as hydraulic binders which do not exactly possess the properties of the cements which, normally, they are destined to form. It is known that the calcium silicates -- providing the utilized water of a sufficient quantity -- become hydrated by furnishing a mixture of hydrated calcium silicates, hydrated lime and eventually of silica. The hydrated silicates referred to as tobermorites are present in the form of hydrates of the general formula x CaO. y SiO 2 . z H 2 O, with x/y between from about 0.4 to about 3 and z/y between from about 0.5 to about 6. The Afwilite of the chemical formula of 3 CaO. 2 SiO 2 . 2 to 4 H 2 O is present as a particular type of tobermorite. The present invention utilizes this last hydration reaction as a source of lime for the manufacturing procedure, beginning with hydrated aluminum sulfate as starting material, of a compound essentially of calcium trisulfoaluminate. SUMMARY OF THE INVENTION Generally speaking, the new compound comprises from about 45 to 93% by weight of hydrated calcium trisulfoaluminate and from about 7 to about 55% by weight of tobermorites of which from about 0 to 25% by weight are hydrated silica counted as SiO 2 . One process for the preparation of the compound according to the invention features a hydration process in accordance with the cited patent; this process is characterized by the hydration of the silicates in an aqueous phase, namely in the presence of an excess of water and at temperatures from about 10° to about 100° C. The hydration process can be applied to the mixture of raw materials or a hydrate from the product containing the silicates which can be formed first to which is added the aluminum sulfate. Finally, all additives, all the mixtures perfected for the manufacture and the traditionally utilized Satin White, can be utilized with the product of the present invention. All other processes known for the manufacture of Satin White can be employed with the same effect. As calcium silicates, one can utilize natural or synthetic mono-, di and tri-calcium-silicates; one can also use industrial products containing such silicates and, more particularly, the white hydraulic Portland cement, which mainly includes di-, and tri-calcium silicates. The commercial form of the white Portland cement, or either ground-up or unground clinkers of said Portland cement are also suitable. Of course, the common grey Portland cement or all types of Portland cement can be employed if there is no concern over the color of the charge obtained. Other products, which are called white limes and which are enriched in di-, and tri-calcium silicates can likewise be suitable. Finally, natural or synthetic anhydrous basic calcium silicates, such as the Wollastonite can be used, but the process is much slower. The tests carried out by the applicants have brought to light the fact that the hydration of the calcium silicate or of the Portland cement, used for the formation of the calcium sulfoaluminate, leads to mixtures of silica and of calcium trisulfoaluminate. If one starts with pure calcium silicates, depending on the selected silicate, one obtains: from about 55 to 7% of tobermorites, of which from about 0 to 25% by weight is hydrated silica, counted as SiO 2 , and from about 45 to about 93% by weight of calcium trisulfoaluminate. The preliminary hydration of the calcium silicate leads to mixtures of trisulfoaluminate and tobermorites. The invention accordingly comprises the several steps and the relation of one or more of such steps with respect to each of the others, all as exemplified in the following detailed disclosure, and the scope of the application will be indicated in the claims. DESCRIPTION OF THE PREFERRED EMBODIMENTS In the following, there is described compounds mixed according to the invention, and their preparation. EXAMPLE 1 Into a standard grinder of the ball-mill type, which is furnished with balls of corundum and with an elastomeric lining to prevent contamination of the tint, there is introduced water and the following mixture, this being done in a manner so that the initial dry extract amounts to about 20% by weight: ______________________________________pure tricalcium silicate 456 parts by weighthydrated aluminum sulfatewith 18 molecules of water 666 parts by weight.______________________________________ The grinder was allowed to turn around for 6 hours while allowing the reaction to liberate the calories which it produces. The temperature increased to about 70° C. The evolution of the chemical reactions can be followed by means of X-ray diffraction analyses and after 6 hours, the total aggregate of the starting materials had disappeared by forming a mixture of calcium trisulfoaluminate and of silica gel, having a composition of about 92% by weight of calcium trisulfoaluminate and of about 8% by weight of silica. This powder was concentrated through filtration, then it was dried through atomization, and it was observed that it comprised micron-sized particles, of small rod-like elements of Satin White and of angular particles of silica gel. The powder displayed the following characteristics: ______________________________________appearance impalpable white powder;fineness 100% <8 micronscomposition co-precipitated mixture of calcium trisulfoaluminate (Satin white) of about 92% by weight and hydrated silica of about 8% by weight. (These percentages are given for the particular conditions of this example);specific gravity 1.98pH of 10% solution 8.5whiteness 94.2%abrasiveness (Valley-method) 12 ± 5 mg.______________________________________ The dispersions of the mixture in water show characteristics of high degrees of thixotropy. This charge can be utilized in the paper-making industry where it distinguishes itself by the characteristics of the Satin White. It can also be utilized in paints as thickening agent, or for the thickening of liquids, or in drilling muds, or the like. EXAMPLE 2 In a grinder equipped with corundum balls, one has completely hydrated 540 parts by weight of commercial white Portland cement of the following composition: ______________________________________SiO.sub.2 23.7 parts by weightAl.sub.2 O.sub.3 2.7 parts by weightSO.sub.3 1.2 parts by weightCaO 69.3 parts by weightFe.sub.2 O.sub.3 0.3 parts by weightvolatilecomponents 1.8 parts by weight______________________________________ by allowing the grinder to turn around under customary conditions and in the presence of an excess of water, during about 14 hours at about 60° C. Through X-ray diffraction analysis, it has been determined that the cement becomes hydrated while furnishing tobermorites and calcium hydroxide. The thermo-gravimetric analysis has revealed that 540 parts of cement have led to 307 parts by weight of lime and 418 parts by weight of tobermorites. Subsequently, 460 parts by weight of aluminum sulfate with 18 molecules of water were progressively introduced into the grinder. One again set the grinder in motion and after 30 minutes, it is observed that the reaction has terminated. In this manner, there is obtained a suspension of intimately mixed white, co-crystallized, crystals of the following composition, namely about 67% by weight of calcium trisulfoaluminate and about 33% by weight of tobermorites. The suspended powder, dried by known means such as atomization, had the following characteristics: ______________________________________appearance impalpable white powder;whiteness 96.7%specific gravity 2.04fineness 100% <9 microns.______________________________________ Thus, the utilization of the tri-calcium silicate has led to mixtures respectively constituted of from about 45 to about 93% by weight of the first constituent and of from about 55 to about 7% by weight of the second one. The quantities of the utilized products allow one, according to simple laboratory tests, to furnish mixtures partially including tobermorites and silica as components and formed from the calcium silicates. The product of the invention possesses the characteristics of fineness, of whiteness, of smoothness equal or superior to those of Satin White. Its specific gravity remains of a very low order of magnitude. However, compared to Satin White, it is capable of forming pastes of much higher concentration in an aqueous medium and therefore, has a great advantage over this pigment. In this manner, formulations for the coating of paper can be made in an easy manner and at a cheap price, e.g., by using this pigment in combination with kaolin. The pieces of information which follow, will give details of the qualities of the compounds according to the invention and utilized in paints. EXAMPLE 3 In order to demonstrate the high quantities in dry extract which one can obtain with the product according to the invention, a comparison between an aqueous dispersion of the product listed in example 2, and of commercial Satin White at about 40% by weight of dry extract can be made. There is added to each of the indicated quantities of the fluidifying polyacrylate as shown in Table 1, the viscosities of the dispersions which were measured by means of a BROOKFIELD viscometer (at 100 rpm and at about 20° C): TABLE 1______________________________________ Dispersion Agent ViscosityDispersion in % by weight in cp______________________________________Satin White 0.6 590Charge in accordance withinvention (Example 2) 0.5 45______________________________________ In another test, there was determined the maximum content in dry extract by weight furnishing pastes having a viscosity of about 5 poises measured by means of a BROOKFIELD viscometer. The following was obtained: TABLE 2______________________________________ concentration at 5 poises:______________________________________:Satin White: 27% by weight:charge accordng to):invention): 54% by weight:(example 2) )______________________________________ EXAMPLE 4 So as to bring to light the qualities of the charge in accordance with the invention, comparison was made for the measured physical and optical characteristics with those of powders of the same degree of fineness: TABLE 3__________________________________________________________________________: kaolin for : Satin White : charge in: coating purposes : : accordance with: : : the invention: : : (example 2)whiteness : 91 : 92.6 94.1specific gravities: 2.60 : 1.92 2.05__________________________________________________________________________ This example illustrates the advantage in the charge in accordance with the invention. The instant charge possesses a whiteness which is superior to that of the kaolin and even to that of Satin White. Moreover, it maintains a specific gravity very close to that of Satin White and of a distinctly lower order of magnitude than that of kaolin, which is a definite advantage for light coatings such as for paper. EXAMPLE 5 An AFNOR VII paper has been coated with a thick preparation solely pigmented with kaolin (I), with a pigmentation consisting of about 80% by weight of kaolin and about 20% by weight of Satin White (II) and, finally, with a pigmentation consisting of about 80% by weight of kaolin and about 20% of the charge in accordance with the invention (III). The following optical characteristics, measured by the traditional methods on a coated paper having one surface coated at 10 g/m 2 were obtained: TABLE 4______________________________________ I II III______________________________________whiteness(Elrepho method)- 82.2 85.2 85.3in %glossiness(photovolts)- 33 42 40in %structure of coating closed micro- micro- porous porousopacity 88.1 89.1 89.1proportion of the starch/latex binder employed for100 parts by weight ofpigment 8/8 8.8/8.8 8.8/8.8tear-off velocity [or rate]in cm/sec. ink 3804 75 cm/sec. 85 cm/sec. 90 cm/sec.______________________________________ Thus, in accordance with the invention, one can produce coating formulas which contribute to the known advantages of Satin White, while considerably reducing its inconveniences and allowing one to realize appreciable savings owing to a better yield of the chemical reaction. It should be added moreover, that this charge can be utilized as a thickening agent for paints, or as a charge for thermosetting products or the like. We wish it to be understood that we do not desire to be limited to the exact details described, for obvious modifications will occur to a person skilled in the art.
A composition is essentially of an ettringite base and contains from about 45 to 93% calcium trisulfoaluminate and from about 7 to about 55% tobermorites, of which from about 0 to 25% is hydrated silica, counted in the form of SiO 2 .
3
BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] This invention generally relates to a system and method for monitoring personnel; particularly, a personnel monitoring system and method having applications in institutions such as hospitals, homes, and penal institutions for ensuring the security of infants and monitoring the movement of children, patients, and prisoners. [0003] 2. Discussion of the Related Art [0004] Monitoring systems are available in which, for example, tags are attached to articles. If the tag and article are moved past a detector placed at a strategic location such as an exit, an alarm sounds. Such shop-lifting prevention systems are widely used in department stores. In many cases, it is desirable to monitor movement of persons and in particular to instantly detect the identity of such persons when such movement is detected. In the particular case of hospitals and penal institutions, it is desirable to monitor movement of individuals from one area to another in the building, or at entrances and exits to the building. [0005] In these cases it is not enough to simply detect movement. It is essential to be able to detect both that movement has taken place, and it is also necessary to immediately identify the person detected. [0006] For example in the case of a hospital maternity ward, where despite close monitoring, the number of infant theft attempts has been on the increase. Infant mixups or swaps have also been recent news items. [0007] The movement, location at any point in time, and identity of individuals in such settings is of paramount importance to those responsible for the safety and well being of the young, infirmed, and incarcerated. [0008] In the particular case of infants or patients in hospitals it is important not only to detect movement from one area to another, but it may also be necessary to institute some form of remedial action such as initiating an alarm or instituting a search when unwarranted movement is detected. SUMMARY OF THE INVENTION [0009] The present invention, in the most general sense, is a personnel monitoring system for locating and identifying individuals within a facility. More specifically, in accordance with a preferred embodiment, the present invention is directed to a child security system for monitoring an infant in a maternity ward setting. [0010] A preferred system of the present invention includes a locator subsystem and a security subsystem. The locator subsystem is capable of determining locations of badges. The security subsystem is capable of monitoring badges and activating alarms upon detection of security breach conditions. It is contemplated that the badges will be worn by infants and designated personnel associated with the infant (e.g., mother, father, nurse, visitors). A plurality of transceiver modules provide monitoring and location functions. A transceiver module (TM) is preferably mounted at the bassinet and another is mounted on a wall in the nursing room. [0011] The TM is capable of receiving and storing signal data including ID signals being substantially continuously transmitted from the infant and adult badges. The transceiver also includes a processor for processing the data (signal strength) from the badges. From the received data the TM processor computes range data for those badges and infant anklet that are within range. The received ID is compared with a stored local “association” database and together with the range information is used to ensure that one of the designated individuals is near the infant (i.e. a non-alarm condition defined by at least one designated person within a pre-defined, programmable, zone of safety around the infant). Badge identification and range determination is achieved using one or both of the wireless IR and RF data link from the adult badges and infant (anklet) to the TM. The two links are considered mutually redundant. [0012] In one aspect of the invention, a method of monitoring one or more infants comprises the steps of: an infant transmitter for substantially continuous transmission of an infant identification signal, said first transmitter being securably attached to an infant to be monitored; a plurality of mobile transceivers to be worn by individuals responsible for the safety of said infant, each of said plurality of badges including a transceiver transmitting a substantially continuous unique identification signal. The system includes a transceiver module comprising: a receiver for detecting the infant identification signal from the infant transmitter and the unique identification signals from the plurality of mobile transceiver; a transmitter for transmitting signals to said plurality of mobile transceivers; and a processor for determining the range of the mobile transceivers, said processor also for generating alarm condition signals. [0013] Since operation is based upon proximity detection and low cost repeaters, the method of the present invention can be effectively employed, for example, at attraction theme parks, children's hospitals, old age homes, and similarly situated venues where personnel detection is at issue. Further, if a wider area of coverage is desired, additional transceiver working in unison (i.e. WEB architecture), could detect that at least one of several networked transceivers is in touch with a particular anklet. [0014] These and other objects, features and advantages of the present invention will become apparent from the following detailed description or illustrative embodiments thereof, which is to be read in connection with the accompanying drawings. [0015] [0015]FIG. 1 is a perspective view of a typical hospital nursery environment with an infant depicted with a portion of a system of the present invention. [0016] [0016]FIG. 2A is a perspective view of a transceiver module assembly of a preferred embodiment of the present invention. [0017] [0017]FIG. 2B is a perspective view of an infant badge (anklet). [0018] [0018]FIG. 3 is a block diagram of components of a transceiver module of the present invention. [0019] [0019]FIG. 4A is a block diagram of major components of an infant badge unit (anklet). [0020] [0020]FIG. 4B is a block diagram of major components of adult badge unit. [0021] [0021]FIG. 5 is a flowchart illustrating an embodiment of a method of personnel monitoring according to the present invention. [0022] [0022]FIG. 6 is a flowchart illustrating a yellow alarm mode. [0023] [0023]FIG. 7 is a flowchart illustrating a red alarm mode. processing mode. [0024] [0024]FIG. 8 is a flowchart illustrating a pressure pad processing mode. [0025] [0025]FIG. 9 is an illustration of an overall system according to the present invention. DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS [0026] [0026]FIG. 1 illustrates an exemplary use of a personnel monitoring system of the present invention. There is shown at FIG. 1 a typical nursery 10 environment as known in hospitals or infant care rooms in which an infant 12 is placed in a bassinet 14 . The infant 12 is wearing an infant badge 15 , which can be in the form of a bracelet, anklet, or a skin contact badge and is tended to by a nurse or care giver 16 wearing an adult badge 20 . It is further contemplated that other persons affiliated with the infant (e.g., mother, father, visitors) would also be assigned badges. Also illustrated in FIG. 1 is a transceiver module (TM) 18 , which in this case is shown mounted on the bassinet 14 . Upon association of the infant and adult badges to the bassinet TM, the bassinet system constitute the basic components of a monitoring system for a single infant, as will be further described below. [0027] A wall mount TM 22 is electronically linked to the bassinet TM 18 and a ceiling unit 10 , which is in turn electronically linked to a central server of a locator system. [0028] As shown in FIG. 2A, the transceiver module housing exterior preferably includes red, green and yellow LED indicators 65 preferably located on the top of the transceiver housing that are software settable and serve to identify the operating status of the TM, for example, red alert, yellow alert or normal operation. A display 60 and a keypad facilitate interface with the TM processor, including data entry and password control. The keypad is preferably of a 12 key telephone type. As will be explained below, the keypad can also be used by the nurse to locate a wandering mom. In this case, the TM will receive the location information based on the information received from the infrared badge worn by the mother. The display would report the location of the mother. Also the keyboard can be used to reset alarms originated from the TM. Alarm conditions are transmitted to other TMs. When an alarm is received, the receiving station will report the type and location of the alarm. [0029] [0029]FIG. 3 shows a block diagram of the major components of a transceiver modules which can be mounted on the bassinet 18 and walls 22 . The transceiver module contains an internal battery supply, but also provides a connection for an auxiliary power pack. It further provides input/output connections to optional external devices such as relays, dry contact closure sensing devices, pressure pads and short range antenna. [0030] The second switch, when pressed, transmits a command, turning on piezoelectric buzzers in all associated badges, excluding the infant anklet, for 15 seconds. [0031] The transceiver module preferably includes embedded infrared (IR) transmitter and two embedded RF receiver/transmitter pairs, a processor DSP 200 with sufficient nonvolatile memory to accommodate downloadable transmission and reception attributes of operating parameters including storage for badge associations, and firmware for operating and controlling the TM. The DSP processor is controlled with a drop out (filtering) algorithm to minimize false alarms. That is, spurious signals falsely interpreted as transmissions from badges. Additionally, each TM is programmed with a unique ID as a factory setting. The unique ID may be imprinted on a label affixed to the unit. The TM can be energized from four lithium cells, which may provide continuous power to the transceiver when an optional auxiliary power pack attached to the bassinet 14 is not used. The TM includes an I/O connector for I/O functions including: 1) relay closures, 2) provide dry contact closure outputs, 3) provide auxiliary power to the transceiver, 4) provide an external antenna, 5) provide data I/O for connection to a host PC when the transceiver is acting as a server node, and 6) connecting an optional pressure pad, lights, and auxiliary power. [0032] There are two RF transceivers in each TM. One communicates with all badges within its area and the other communicates with all other TMs. The badge transceiver with antenna 210 operates at a frequency of between 300 and 400 Mhz and the TM transceiver with antenna 220 preferably operates above 900 mHz. The badge transceiver 210 is preferably designed such that the transmitter's power and the receiver's sensitivity are sufficient to communicate at a distance of at least 100 feet. Under such circumstances, the transmitted signals would certainly be received by an RF receiver disposed approximately 30 feet from its associated transmitter. Signal conditioners 216 and 226 include waveshaper and amplifier which amplify the signals received by receivers 212 and 222 . The conditions include a plurality of operatinal amplifiers for detecting the energy level of the received signal. The operation amplifiers (not shown) are connected as comparators which are set at different thresholds. The comparators are monitored by the processor 200 for determining the energy level of the signal received. Connector 218 can be used to connect to a secondary antenna and pre-amplifier. The TMs include display 240 , LEDs 260 , and speaker 270 for audiovisually indicating alarm conditions. I/Os 280 are connectible to a plurality of sensors or actuators. Sensors can be pad sensors placed in bassinets. Actuators can be controls for relays to lock doors if necessary. I/Os 280 can also be interrupts to processor 200 for triggering event or logical processes. [0033] An infrared transmitter with IR LEDs 230 transmits the TM identification data to an infrared receiver (ceiling unit 10 of FIG. 1), IR conditioner 234 receives a serial bit data stream to be transmitted from the processor 200 . The modulator 234 generates a carrier signal which is modulated by the serial data. The modulation can be by FM or ASK techniques known in the art. The modulated signal is fed to an LED driver 232 for providing current driving capability to LEDs 230 . Descriptions of an FM infrared transmitter/receiver can be found in U.S. Pat. No. 5,366,022 to U. Segov, the disclosure of which is incorporated by reference herein. [0034] According to an alternate embodiment, the TM includes an infrared receiver (not shown) for receiving infrared signals transmitted from adult badges or other TMs. [0035] Infrared receivers are disposed in ceiling units ( 10 of FIG. 1). The receiver is capable of receiving infrared transmissions from badge units, preferably at a distance of about 30 feet. The ceiling unit infrared receivers are electronically linked to the central server, which serves as the central processor of the system. The central processor receives badge and TM identification data relayed from the ceiling units. The locations of each transmitting badge or TM unit is determined by the central processor. U.S. Pat. No. 5,455,851 describes in detail a location system useable as the locator system described herein. The disclosure of the '851 in its entirety is incorporated by reference herein. [0036] The use of infrared signaling in addition to RF signaling offers several advantages. Infrared signaling its line of sight transmission path can be reused in each room without interference from other IR sources and thus allowing a backup means of data transfer while providing precise location information. Preferably the IR radiation is low level, non-coherent and totally eye-safe to avoid any eye damage and is in compliance with government regulation. The IR system is preferably a pulse infra-red operating at a selected data rate. The use of a periodic burst mode of transmission is preferred rather than a continuous mode of transmission, reducing the power consumption of the badges while allowing several IR devices to simultaneously transmit within a given area. This reduced power requirement enables the use of rechargeable battery powered transmitter units (badges) having a reasonable operating cycle. [0037] Referring now to FIG. 2B, the infant badge is a disposable RF transmitter containing a unique ID, implemented at the factory. The badge is both small and lightweight so that it may comfortably wrap around an infant's leg without interfering with the movement of the infant 12 . The infant badge somewhat resembles a charm 32 with the RF circuitry encapsulated in a rugged plastic enclosure. The infant badge is preferably hermetically sealed to be able to withstand typical hospital disinfecting procedures. The strap 30 has an embedded antenna 36 . Mechanical and electrical interlocks 37 are suited to multiple uses including an ability to tighten the strap as the baby dehydrates after birth. The electrical interlocks detect a loss of continuity. Under normal operating conditions, the badge 15 transmits power with a preferred transmit duty cycle of 0.02% at a 1 second or more rate. The rate of transmission is preferably in the range of 0.5 seconds to several seconds, being set at a manufacturing stage. An alternate embodiment of the infant badge uses an adhesive pad 38 . This pad and associated electronics allows for a measurement of skin capacitance. If the badge is removed from the baby's skin an alarm will occur. [0038] [0038]FIG. 4A shows the components of an infant badge 400 . The preprogrammed badge 10 is transmitted via RF transmitter 412 via antenna 410 . The interlock or contact sensors are connected to I/O port to interrupt processor 416 upon detection of a broken strap or contact. [0039] [0039]FIG. 4B illustrates major components of an adult badge 440 . The adult badge unit includes an RF transmitter 452 and an infrared transmitter 458 . Each badge is preprogrammed with a unique ID as a factor setting for recognition by the TM 18 . The badges will preferably transmit RF in the 300 to 400 mHz frequency range. The badges will preferably transmit between 5-15 mwatts at a 0.02% duty cycle. Other embodiments may consider alternate frequency transmission ranges and transmission powers. The infrared (IR) transmitter 458 is used to transmit badge ID data to ceiling unit receivers for location determination. In an alternative embodiment, RF transceiver 452 receives RF signals, including alarm signals from TM 18 . A piezo buzzer 466 audibly alerts the badge holder of such alarm. In a further embodiment, IR receiver 464 facilitates receipt of IR signals. [0040] Referring again to FIG. 1, a pressure pad can be placed on a bassinet 14 to detect the lifting of an infant from the bassinet. the pressure pad can be positioned on the underside of the bassinet mattress and connected to the bassinet TM 18 via a connector (not shown). In operation, when an infant 12 is lifted from the bassinet 14 , TM 18 senses a relay closure in the pressure pad and switches from a long range antenna mode to a close range antenna mode for a short duration, for about three seconds in a preferred embodiment. In short range antenna mode the TM 18 scans the immediate vicinity surrounding the bassinet 14 to determine the identity of third parties nearest the infant 12 . If an associated badge 20 and/or infant badge 15 is detected, no alarm will sound. An alarm will sound, however, if the wrong baby has mistakenly been placed in the bassinet 60 or an associated badge is not present. [0041] A TM and an infant badge form a basic monitoring system, which will provide rudimentary protection by giving an audible alarm at the TM whenever the infant is moved beyond a prescribed safety zone or distance. [0042] Before the core components of a monitoring system are placed at a monitoring location such as at a maternity ward, they must be electronically “associated”. That is, when a TM is field deployed it must have some means of recognizing transmissions from badges. That is, the present invention contemplates the simultaneous deployment of similarly situated monitoring systems for monitoring a plurality of infants. As such, the TMs receive transmissions from both the infant and adult badges within its receiving range. It must therefore be capable of distinguishing transmissions received from badges associated with the transceivers and nonassociated badges. [0043] Performing an electronic association for a single hardware set (e.g., associated an infant badge and a plurality of adult badges can preferably be done by placing the TM in close proximity to the badges to be associated and depressing an association button or keypad on the TM, preferably by selecting an ‘association’ mode from the keypad and display of the TM for a predefined duration of time. The badges transmit their respective IDs and the TM processor places the associated IDs in its memory. Preferably, upon association, the processor the TM displays the associated badges and signals the completion of the association process. Alternatively, badges to be associated are placed inside a Faraday bag (i.e. an electronic signal isolation bag where signals cannot travel beyond the confines of the bag) to perform the “electronic association”. The Faraday bag ensures that only those selected components that define a monitoring system for a particular infant (i.e. hardware set) will be “electronically associated”. [0044] When a woman checks in to give birth, she is given a RF badge and an ILS badge and the badge information is entered into the control server. The information could be downloaded into MIS or central computer. A bassinet is selected readying for delivery of the baby. The bassinet TM transceiver module can be electronically associated with the mom's badge and her ID. The selected bassinet is moved to the mom's delivery room. Several badges including at least one infant badge should be found or placed in the bassinet, ready for association with the bassinet TM. When baby is delivered, or even prior to delivery of the baby, the infant badge is associated to the bassinet TM by electronic association as previously described. The associated infant badge is attached to the infant. At that time, baby related data such as weight, size or name can be keyed into the bassinet TM. The information can then be uploaded to the wall TM and then central server or computer. Other badges can be associated for family members and visitors to the bassinet TM using the same association process. In the case of multiple births, the associated badges could be copied by all associated data downloaded to a second bassinet TM. A second infant badge is associated with the second bassinet TM. Upon delivery, the infant is placed on the bassinet, no association to wall TMs has yet been performed. When the baby is moved to the nursery, the assigned room is programmed into the bassinet TM or when the bassinet is physically placed in the room, a selection is made on the keyboard to associate that room to the bassinet TM. Once associated, the bassinet TM links with the wall TM which in turn is linked to the central server unit. The infrared locator system (ILS) in the room receives badge transmissions from the bassinet and wall TMs. [0045] The RF system and the ILS system provide two layers of electronic protection. The RF system (“electronic leash”) protects a given range (approximately 15 feet for yellow alarm and 30 feet for red alarm) whereupon if an infant badge is detected to be more than the specified distance, a yellow or red alarm sounds or is displayed. The ILS provides a more precise measure of protection by having the capability to isolate and identify the location of the bassinet TM. Thus, while the RF electronic leash may not be violated, such as when the baby is placed erroneously in an adjacent room, the ILS will detect such error and sounds an alarm. [0046] In an exemplary operation, when the mother is admitted to the hospital, the already associated devices are assigned to the mother. The nurse/care-giver scans a bar code or types in mom's name or other personal identification in the TM. The TM then accompanies mom until delivery, at which point, the associated infant badge is placed on the newborn, the TM is placed either within the bassinet or adjacent to it, and the pressure pad is connected to the TM. The remaining associated guest adult badges are then returned to the nurses station. When visitors arrive they may or may not be required to carry a badge subject to hospital policy. When a bassinet is placed in a nursing room, a wall mounted TM is associated with the bassinet TM. The infant badge periodically transmits the ID to the bassinet TM. [0047] Each associated badge transmits an RF ID that is decoded by the bassinet TM and compared with a pre-stored local ‘association’ database, and together with the calculated range information, a determination is made as to whether a responsible person (e.g., caregiver, mother, father, visitor) wearing an “associated” badge is within an acceptable range of the infant. The acceptable range is a dynamically programmable value that may change as circumstances require. Such change command may be downloaded from central server to wall TM and to bassinet TM. Note that in the general case, when multiple hardware sets are in simultaneous use, the “association” database serves to discriminate between associated and non-associated RF badge transmissions. [0048] The bassinet and wall TMs communicate via their RF transceivers (at about 900 Mhz). The wall TM is in turn electronically linked to central server via a local area network. Information received by the bassinet TM is communicated to the central server for event and data processing. Location information resident on the central server is typically used for performing event processing. For example, a determination of the badge wearers within a room. Infant, mother and associated data can also be uploaded to the central server in such a way. Alternatively, the wall TM can communicate (via infrared) with the infrared receiver at the ceiling unit, without connecting to a wired network which is in turn electronically linked to a central server. In such mode, all communications are wireless and the expensive ‘wired’ installations are dispensed. ALARM CONDITIONS [0049] Alarms are generated under 3 general scenarios: 1) when it is determined that a responsible party is not within a predefined safe distance from an infant, 2) whenever the infant is removed from the bassinet by a non-authorized party, and 3) when the infant is removed from the bassinet by an authorized party beyond a preprogrammed safety zone. [0050] Under the first scenario, the associated badges and infant badge substantially continuously transmit their IDs and range positions to the bassinet TM are determined. The TM is pre-programmed with a safe distance value that determines a maximum allowable separation distance between the infant and at least one responsible party. If the bassinet TM cannot locate at least one responsible party being within a safe distance of the infant an alarm condition occurs. It is important to note that the pre-programmed safe distance value can be changed dynamically, as circumstances require. This feature could prove useful during baby transport between departments to ensure that a responsible party is even closer to the bassinet than would normally be required. All alarm conditions are signalled at the bassinet TM with the appropriate colored LED and/or speaker. The alarm conditions are transmitted to the wall TM which in turn forwards the alarm to the central server via the ceiling unit. According to one embodiment, alarms can only be reset manually at the TM originating the alarm. [0051] Under the second and third scenarios, whenever the infant at issue is removed from the bassinet, the act of removing the infant is detected by the bassinet TM via the pressure pad located beneath the mattress. This action switches the receiving antennas in the TM from a long range high sensitivity antenna to a close-range proximity antenna for a few seconds, on the order of 3 seconds in a preferred embodiment. The range of the close proximity antenna is preferably less than about twelve feet measured from the center of the bassinet. Switching from long to close range antenna mode is intended to identify the badges within close proximity to the bassinet. If the close proximity antenna does not make a proper badge association, a red alarm condition is automatically triggered within the bassinet TM. Detecting an improper association is advantageous for a number of reasons including: 1) if a person is not authorized to pick up the baby, irrespective of whether he or she is wearing a badge, the unauthorized act of removing the baby from the bassinet will automatically sound an alarm at the bassinet TM and also at any central node and secondary transceivers in use, and 2) if a baby is mistakenly placed in the wrong bassinet, the primary transceiver cannot make a proper association thereby causing a read alarm condition. [0052] If, however, the person removing the infant from the bassinet is properly associated (i.e. wearing an electronically associated badge) then under the third scenario, further safeguards are activated whenever that person attempts to stray outside the predefined zone of safety around the bassinet. [0053] The zone of safety can be discussed as two circumferential perimeters centered about the bassinet, a first perimeter defining an inner safety zone, preferably on the order of 15 to 20 feet from the center of the bassinet, and a second perimeter defining an outer safety zone, preferably on the order of 30 feet from the center of the bassinet. If the person holding the infant strays beyond the first perimeter, the bassinet TM will go to yellow alert, illuminate a yellow flashing warning light, warning that person that they are about to exceed the outer safety zone (i.e. second perimeter). If that person does not move back inside the bounds of the first perimeter within some pre-programmed time, preferably around 30 seconds in a preferred embodiment, then the light on the bassinet TM will go to red (i.e. red alarm condition). The bassinet TM sounds an audible alarm and transmits a red alarm condition. Further, whenever the infant is moved beyond the bounds of the second perimeter an immediate red alarm condition is generated at the bassinet TM. In one embodiment, the red-alert alarm condition transmitted from the bassinet TM is received by the RF receiver 464 in the associated adult badges. The red-alert condition is transmitted to the wall TM 22 via the TM to TM RF link and in IR to ceiling unit 10 , which in turn relays the alert condition, including the ID of the originating bassinet TM 18 to the locator central server. As previously described, the central server has location information on all badge wearers and thus can alert all appropriate personnel of the hospital including central nurse stations personnel to the infant. [0054] In one embodiment, the wall mounted TM 22 is connected to a computer net work with a LAN. Such wall TM unit is switched or selected to be in central node (CN) mode. Data uploaded from the bassinet TM 18 can in turn be forwarded to a central server of the network and stored in central database. Preferably, the computer network is connected to the infrared locator system (ILS) for exchange of database and location information. The wall TM 22 can also be used to relay infrared data (to ceiling unit 10 ) if the bassinet TM 18 is not equipped with an IR transmitter. [0055] A detailed description of a preferred embodiment of the monitoring and locating system of the present invention will now be given in the context of the flowchart of FIG. 5. [0056] It should be appreciated that more than one set of associated hardware may be simultaneously utilized within a monitoring environment for the purpose of monitoring a plurality of infants. The following description explains the invention in terms of monitoring a single infant. At step 70 , all timers and relays within a module are reset. Step 72 is a determination step to determine whether the transceiver is set to operate in central node (CN) transceiver mode or as a bassinet transceiver. If the switch setting indicates central node transceiver mode then a branch will occur to the CN operation. At step 74 a determination is made concerning the activation of the self test timer flag. If the flag is active the transceiver broadcasts an “I'm OK” signal to any other transceivers within its receiving range (step 76 ). Next at step 78 , the internal timer is reset for some predetermined time interval for a re-transmission of the “‘I'm OK”’ signal. At step 80 , the self test timer is decremented. Step 82 is a determination step to decide whether the association button has been depressed on the transceiver. Depressing the association button associates IDs received by all badges transmitting to the transceiver during the association process (step 83 ). The associated badge IDs are stored in the association database of the bassinet transceiver module. At Step 84 a determination is made whether a state change has occurred in the pressure pad. If so, the process branches to step 146 (FIG. 8). [0057] At step 146 , a 3 second interval timer is started. The bassinet TM will switch from long range antenna mode to short range antenna mode inside this 3 second interval. In addition, the pad latch will be set. At step 148 the timer is decremented by some fixed amount. Step 150 is a decision step to determine whether a close proximity signal has been received by the TM. If not, then the process continues at determination step 152 to determine whether the counter has timed out. If so, a report is forwarded by the bassinet TM to the wall TM acting as a central node transceiver, describing the reason for the alarm condition (step 164 ). If the counter is determined to be other than zero at step 152 , then the process repeats the 148 - 150 - 152 loop until either the counter times out or a signal is detected. If a signal is detected at decision step 150 , a branch occurs to a filtering algorithm to determine whether the detected signal is a false signal (step 154 ). If it is determined that the signal is not a false signal, a determination is made whether the infant currently being detected by the close proximity antenna is in fact the infant to be monitored (step 156 ). Such a determination will be made by the ID transmitted by the infant's badge. This ID is checked against the IDs stored in the association database of the bassinet TM. If it is determined at step 156 that an infant other than the infant to be monitored is detected (i.e. an incorrect infant), the process continues at step 158 . Step 158 is a determination step to determine whether the detected signal is associated with a responsible party (i.e. staff, parent, etc..). If not, then the process returns to decrement the counter at step 148 . Otherwise if it is determined at decision slep 156 that the correct infant has been detected then the process continues at step 160 where an infant flag is set true. Otherwise if it is determined at decision step 158 that a responsible party was detected then a staff/parent flag/is set true at step 162 . From either step 160 or 162 , the process continues at decision step 166 , wherein a determination is made whether both the infant and staff/parent flags have been set. If so, at step 168 the pad latch, which was previously closed to initiate the alarm condition, is now cleared. The process then returns to step 74 (FIG. 5). [0058] Returning to FIG. 5, when the monitoring system is operating in normal mode, i.e., the bassinet TM has the green LED lit. The processor in bassinet TM continually monitors the infant (steps 92 to 100 ). Decision step 94 makes a determination as to whether the infant is located within the 30 foot safety zone perimeter of the bassinet. If not alarm mode processing will occur (See steps 128 - 144 ). Otherwise, if the baby is within the 30 foot perimeter, it is then determined at step 96 whether the infant is within the 15 foot inner perimeter. If not then the processing steps associated with a yellow alarm mode occur. [0059] Referring to FIG. 6, steps 106 - 126 are the processing steps associated with handling a yellow alarm condition. The 15 yellow alarm mode processing results from decision steps 96 , 98 , and 104 of FIG. 5. At step 106 , the yellow LED on the bassinet TM is lit. Where appropriate, relays controlled by the bassinet or wall TM are activated. At step 108 a timer is set to some predetermined number of seconds within which the infant must be returned inside the bounds of the first perimeter (i.e. safety zone). At step 100 , the yellow alarm condition is transmitted to the central node transceiver (wall TM). Step 112 is a determination step to determine whether a valid signal has been received while the timer counts down. If not, the process branches to decision step 132 to determine whether the counter has timed out. If not the counter is decremented at step 124 and the process loops back to decision step 112 to determine if a valid signal has been received. Otherwise, when a signal is received at step 112 a branch occurs to the drop out test algorithm to determine whether the signal is valid. If an invalid signal determination is made the process branches to step 122 to determine it the counter has timed out. If the counter has not timed out the counter is decremented at step 124 and the process returns to step 112 . Otherwise if the counter has timed out without a valid signal present (See step 116 ) the process continues at step 126 where the yellow flags, latches, counters, and relays are all reset. The process then branches to the processing steps associated with the red alarm mode (See steps 128 - 144 ). If, on the other hand, a valid signal is determined to be present at step 116 then the process continues at step 118 . Step 118 determines whether an associated badge signal is within safe distance. That is, the yellow condition was initially triggered from a negative response at decision step 96 . A no response at this step indicates that the baby is outside the inner perimeter. When this situation occurs it must be determined whether a care giver is in close proximity. This determination is made at decision step 118 . If a care giver is within close proximity the yellow alarm condition can be reset. This occurs at 10 step 120 . The process then returns to step 74 of the main loop. [0060] Referring to FIG. 7, steps 128 - 144 are the processing steps associated with handling a red alarm condition. At step 128 a 3 second timer is started. Next, at step 130 , an alarm broadcast is made to all associated badges and the central node transceiver. At step 132 a determination is made whether a signal has been received by the bassinet TM. If so, a branch occurs at step 134 to the drop out algorithm to determined whether the received signal is a false or a valid signal. If a valid signal is detected the process continues at determination step 136 where a determination is made whether a caregiver is in the room with the infant. If not, then the process branches to step 142 where the 3 second counter is decremented. Next, a determination is made at step 144 whether the counter has timed out. If not the process loops back to step 132 . Otherwise, if the counter has timed out with no care giver in the room the process loops back to step 130 where the alarm broadcast will be re-transmitted to all associated badges and the central node transceiver (wall TM). Step 142 checks if it is determined at step 138 that the reset has not been pressed on the primary transceiver. If so, the process continues at step 138 . Step 138 is a determination step to determine if the reset has been pressed on the primary transceiver. The process then continues to step 140 where the red alarm latch, flag conditions, and counters are all reset. [0061] Returning to FIG. 5, step 100 is a decision step to determine whether any new instructions have been received from the central node transceiver (wall TM). if new instructions are received from the central controller via the wall TM, then a branch occurs to respond to the new instructions. If no new instructions have been received the process continues at step 102 . Step 102 is a determination step to determine whether a read alarm has been set. If so, the process branches to the steps associated with red alarm mode processing (See steps 128 - 144 , described above). Otherwise, if not red alarm was set the process continues at step 104 where a determination is made concerning whether a yellow alarm has been set. If so, the process branches to the steps associated with yellow alarm mode processing (See steps 106 - 126 , described above). Otherwise the process returns to determination step 74 of the main loop. WANDERING BABY MODE [0062] From time to time it is necessary for an infant in maternity ward to be moved from one room or area of a ward to another. Such movement presents potential problems for a security system. The wandering baby mode addresses the needs of the enhanced security mode required under such a scenario. This mode insures that a responsible person is even closer to the bassinet than would normally be required. In operation, when a bassinet and infant are being transported from point A to point B, a central node transceiver wall TM would pinpoint the bassinet location and then change the sensitivity of the primary transceiver's receiver in response via an RF transmission from the central node transceiver as a function of location. For example, the first perimeter safe distance could be changed from 20 feet to 8 feet +/− 3 feet when movement of the infant is contemplated. INFANT TODDLER HOME ALARM [0063] Another exemplary usage of the system is to provide additional service outside the hospital setting. At discharge time, the infant anklet and the battery module of the badge may be given to the mother as a memento of her stay. The battery module is preferably intended to attach to a key ring (hereinafter referred to as a Key Chain Tag, KCT). The KCT would include the IR/RF transceiver designed to receive alarm commands and transmit ID and key press information, and a piezoelectric beeper for audible alarms. On the rear of the KCT is a bar code containing several hundred bytes of encrypted information about the child. In conjunction with the KCT and infant anklet which are given to the parents at discharge, if a bassinet TM is also given to the parent, it can be attached to a crib or stroller for outdoor use. Pressure pads may also be used with the crib or stroller as previously described. Siblings badges which operate in a similar manner as the infant anklet allow additional sibling to be monitored; and a specialty badge that is designed with moisture detectors that will transmit an alarm if in contact with water (if a pool is nearby). The infant anklet remains a functioning transmitter and the KCT is a functioning transceiver that will continue working for several years. In home operation, if the infant is moved by anyone without the mother's KCT present, an alarm will occur at the KCT. This can provide a deterrent to curious siblings or grandparents who desire to hold the baby but should not. As the infant matures and begins to walk, the same infant anklet, KCT, and primary transceiver can be used to ensure the toddler stays within a certain distance. As the child becomes increasingly independent, the primary transceiver can be placed outdoors to ensure that the toddler stays within an assigned play area. If the child roams outside the assigned play area, the primary transceiver will transmit an alarm to the mother's KCT. As an additional contemplated use, the primary transceiver can be configured to alarm whenever a child enters a restricted area. This allows for very effective coverage when multiple transceiver units are used. SECURITY AND ACCESS CONTROL [0064] Although the primary transceivers primary use is as an infant monitoring device, the units may also be used at remote locations to provide access control or emergency alarms in areas that would otherwise be unprotected. For example, the units could be placed in the hospital parking lot to minimize the threat of attack from strangers. For example, if a person in the parking lot feels threatened, a press of his or her Keychain Tag (KCT) would be received by the nearest transceiver to instantly identify his or her location. The transceiver can be pre-programmed to summon help in those situations. OTHER BENEFICIAL FEATURES [0065] A situation may occur involving a lost badge which would Compromise the security of the system. To locate the lost badge, an administrator may program a central node transceiver to transmit a “lock down” mode to all receivers within transmitting range. Immediately, the yellow lamps on each transceiver will flash thereby permitting only a few select people access to the newborns until the lockdown is cleared. Each of the transceivers receiving the instructions may be individually programmed to allow specific persons access and to deny others similar access. As such, a heightened security level is achieved. In addition, because each of the transceivers are remotely programmable, any particular transceiver, or all transceivers may be instructed to look for a match of the missing badge ID and report on the location of the missing badge and enable the audible alarm on that missing badge, thus identifying the location of the lost or stolen device. [0066] [0066]FIG. 10 shows the overall connection of the monitoring and location system according to the present invention. A plurality of IR receivers (ceiling units) 10 are connected to central server 55 . Each ceiling unit receives IR transmissions from badges and TM units 18 , 20 , and 22 . The received IR information is relayed to central server 55 . Based on the information received, central server 55 determines the location of each of all t transmitting badges and TMs by identifying the ceiling unit which forwarded the IDs. Central server 55 processes the information and stores the location information in its associated database. Such information is retrievable by a phone system PBX 50 connected to the central server. Location information can also be retrieved from central server 55 via a local area network (LAN( 60 , which in turn is connected to a plurality of wall transceiver modules (TM) 22 and PC workstation 42 . Within each room, badges 20 communicate with a bassinet TM 18 by RF and communicates with ceiling unit 10 by IR. The bassinet and wall TMs 18 , 22 transmit their ID's to ceiling units 10 via IR. The bassinet and wall TM units 18 and 22 communicates with each other in RF. U.S. Pat. No. 5,455,851 describes in detail the communication of location information having a structure similar to the illustrative system of the present invention. The disclosure of '851 patent is incorporated by reference herein. [0067] In operation, infant badge 15 and badge 20 communicate to bassinet TM 18 . Badges 20 also communicates their IDs to IR receiver 10 . Information received by bassinet TM 18 is communicated to wall TM 22 , which can be forwarded to central server 55 through LAN 60 . Accordingly, the precise location of each transmitting badge and transceiver module is known at central server 55 . Such information is retrievable from any TM 18 or 22 by keypad selection for location information. All information forwarded from bassinet TM 18 can be forwarded to central server 55 via wall TM 22 and LAN 60 including alarm conditions. Upon receipt of such alarm conditions by central server 55 , response commands can be issued by central server 55 to all personnel or a nurse station at workstation 42 to take necessary measures. Each of the wall TM 22 and 23 is capable of activating actuators such as nurse follow dome light 56 outside of each room. Triggering of relays to activate locks at entryways by TMs 22 , 23 is also contemplated. With the location and association technology employed according to the present invention, each infant, caretaker, and parent location and identity can be dynamically pinpointed and their movement tracked. Further, different alarms can be set and conditions interrogated to appropriately respond according to designed commands. [0068] It should be understood that various changes and modifications to preferred embodiments described herein will be apparent to those skilled in the art without departing from the spirit and the scope of the invention.
A system and a method for monitoring objects including infants. The system and method having a first transmitter attached to the object to be monitored, the first transmitter transmits an ID corresponding to the first transmitter. A transceiver associates transmitters by storing in memory IDs of respective transmitters. The transceiver receives the ID corresponding to the first transmitter and compares the received ID with the stored IDs. An alarm is activated upon failure of a preset condition based on signals received by the transceiver.
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CROSS REFERENCE TO RELATED APPLICATIONS [0001] This application claims priority from PCT application no. PCT/EP2005/000186, filed Jan. 12, 2005, which is based on German Application No. 102004002825.7, which was filed Jan. 12, 2004, of which the contents of both are hereby incorporated by reference. BACKGROUND OF INVENTION [0002] The invention generally relates to an operating device for an electrical appliance, as well as to an electrical appliance incorporating such an operating device. [0003] Various types of operating devices for operating electrical appliances that are actuated by placing a finger or exerting a slight pressure with a finger are known. For example, EP 859 467 A and EP 859 468 A disclose an operating principle in which a capacitance change can be brought about in a capacitive sensor element, without exerting a significant pressure or a covered operating path. This can be evaluated as an actuation. [0004] It is also known from DE 198 11 372 A to place beneath a panel of an electrical appliance on the metal frame of a glass ceramic cooking hob or electrical cooktop, a switch having a piezoelectric element. If a finger is placed on the panel area and a certain pressure exerted, said pressure can be detected by the piezoelectric element and evaluated as an actuation. However, the use of piezoelectric elements may be disadvantageous in that piezoelectric elements are relatively expensive and in part mechanically sensitive. BRIEF DESCRIPTION OF THE DRAWINGS [0005] Embodiments of the invention are described in greater detail hereinafter and the attached drawings, wherein: [0006] FIG. 1 illustrates a section through a sandwich structure of an operating device according to the invention; [0007] FIG. 2 illustrates a plan view of a layer of the operating device of FIG. 1 with several juxtaposed sensor elements; [0008] FIG. 3 illustrates a plan view of the insulating layer; and [0009] FIG. 4 illustrates an oblique view of a hob, integrated into the frame of an operating device as in FIG. 1 . DETAILED DESCRIPTION OF THE EMBODIMENTS [0010] One problem to be solved by the invention is to provide an aforementioned operating device and an electrical appliance equipped with such an operating device making it possible to avoid the prior art shortcomings and in particular so as to increase the range of uses of capacitive sensor elements, whilst simultaneously achieving robustness and reliability in daily use. [0011] This problem is solved by an operating device having the features of claim 1 and an electrical appliance having the features of claim 20 . Advantageous and preferred developments of the invention form the subject matter of further claims and are explained in greater detail hereinafter. By express reference the wording of the claims is made into part of the content of the description. [0012] According to one embodiment of the invention, the operating device has a variable-shaped or elastic operating field, which typically is a planar surface of a material that can be slightly deformed by a pressing action onto an area, which can be accomplished by the application of a finger with pressure thereto. The pressure triggering the operation is in the form of a force of a few Newtons. Under the operating field is a capacitive, preferably flat sensor element in the form of an electrically conductive, lower sensor surface. The latter forms a capacitor plate of the capacitive sensor element. Between the operating field and sensor element/sensor surface is a dielectric layer. The operating field is metallic or otherwise electrically conductive on the outside or top. If in the aforementioned manner, pressure is exerted on the operating field, the latter approaches the lower sensor surface, and the dielectric layer becomes thinner and causing a capacitance change on the sensor element. This capacitance change from an initial specific value is monitored by a corresponding evaluation circuitry. The capacitance change generally corresponds to a specific applied pressure causing a specific change of the operating field, which is detected as the user's operation of the appliance. [0013] An advantage of the invention is that a capacitive sensor element with the advantages of its control and evaluation can also be provided with a metallic surface of the associated operating field. It is in particular possible to integrate this into a larger metallic surface, whereof a non-separated area, which can be optically marked, is used as the operating field. It is in particular also possible to provide several different sensor elements or operating fields beneath a through metallic surface, without there being mutual influencing or interference between the sensor elements. [0014] The operating field or the material from which the sensor is made can be electrically conductive throughout. It is preferably constituted by a single material layer. If it is constructed in uninterrupted manner in the vicinity of the operating device or the one or more operating fields, it is possible to create an easily cleaned and relatively insensitive surface for the operating device. It is possible to construct an operating field from thin metal, for example having a metal foil with a thickness of less than 1 mm and in particular as thin as 100 μm. The material can be constituted by various metal alloys having an adequate elasticity for the indicated requirements. It is in particular possible to use high-grade steel or a chromium-plated metal which, as a result of their characteristics in connection with corrosion resistance, offer important advantages. [0015] The dielectric layer can be constructed in numerous different ways. The capacitance, as an absolute value on the sensor element, can be influenced by means of the associated dielectric constant. The main requirement made on the dielectric is compressibility as a result of the aforementioned, advantageous actuating force. It is also possible to use air as the dielectric layer. For this purpose, a certain spacing is advantageously left between the sensor surface or element and the operating field. The dielectric layer can be thinner than 1 mm and is preferably as thin as 100 μm. [0016] In a preferred embodiment of the invention, there are several sensor elements each having a sensor surface and operating fields over the same, as well as dielectric layers between the same, which are juxtaposed and have a certain mutual spacing. A simplification can be brought about if the operating fields are made from a material, particularly flat material, which is used throughout, such as a metal plate or foil. Advantageously, there are no openings, so that the surface is water-tight and can be easily cleaned. Interruptions, recesses, etc., in order to achieve the limited thickness for elasticity for compression purposes, are preferably provided on the underside, i.e. towards the sensor elements. [0017] A sensor surface can be surrounded at a certain distance, particularly a few millimetres, by a conductive surface, which forms a grounding surface. In the case of an operating device with several juxtaposed sensor elements, it is advantageous to provide a common, electrically connected or continuous grounding surface. During the manufacturing process, this surface can be formed from the same metal layer as the sensor surface faces and electrical separation is brought about by appropriate structure. In certain circumstances, a spacing layer can be provided in order to separate the sensor surface and any possible grounding surface from an electrically conductive underside of the operating fields, as well as to create space between the sensor surface and operating field for the dielectric layer. The latter should comprise insulating flat material, which can also be applied as a workable layer. Recesses can be provided in the vicinity of the sensor surfaces, so as to form the air dielectric layer. It is alternatively possible to form the spacing layer from a material having a suitable dielectric constant and appropriate thickness, which is then located between the sensor surface and operating field and which must be adequately compressible. [0018] According to a further development of the invention, the operating field can be made from a flat material or cover, which is considerably larger than the operating field. This makes it possible to construct an operating device, such as an electrical appliance, with one or more sensor elements and therefore also one or more operating fields in a cover or side wall. Thus, an operating device constructed in this way can be integrated into such a wall and, in particular, also into an electrical appliance. It is possible make the cover or its material thinner in the vicinity of the operating field than in other areas. To this end, it is possible to make material recesses on the underside by material-removing methods or by deforming methods, such as punching or stamping. Thus, a wall which offers a hold or protection can be made thinner in certain zones or areas, in order to locate the operating fields of an operating device. One possibility for such a cover is a panel of an electrical appliance, for example a front panel or frame. [0019] An electrical appliance according to the invention has at least one operating device, which corresponds to one of the above-described constructions. For this purpose, the electrical appliance advantageously has an operating area, at which the operating device is located with the one or more operating fields. For example, the electrical appliance can be a cooktop or stove with a side part, which on at least one side can be in the form of a panel or an all-round frame. The operating device is integrated into said side part or frame, for example with sensor elements located beneath the side part or frame. [0020] These and further features can be gathered from the claims, description and drawings and the individual features, both singly or in the form of subcombinations, can be implemented in an embodiment of the invention and in other fields and can represent advantageous, independently protectable constructions for which protection is claimed here. The subdivision of the application into individual sections and also the subheadings in no way restrict the general validity of the statements made thereunder. [0021] FIG. 1 diagrammatically shows in section an operating device 11 having an operating field 13 on which is placed a finger 14 exerting a slight pressure for operation or triggering an operation. On the top surface of the metal surface 25 near the operating field 13 , optically detectable markings (e.g., indicia) such as inscriptions, impressions, etc may be indicated. There can also be a corresponding surface structuring, for example using symbols by means of depressions or elevations. [0022] The operating device 11 has a sandwich structure, which will be explained hereinafter. A metal coating 17 is applied to a printed circuit board 15 as a support. The metal coating 17 is subdivided into sensor elements 17 a , whose flat shape with connection can be seen in the plan view of FIG. 2 and which form the aforementioned sensor surfaces. In place of a square shaping of the sensor elements 17 a , it is obviously also possible to use round, oval and elongated shapes. The sensor elements 17 a are worked out of the metal coating 17 through frame cutouts 18 , whose corresponding structure is also visible in FIG. 2 . The surrounding metal surface 17 b forms a type of grounding surface. The metal coating 17 can for example be applied as a copper coating using conventional methods to the circuit board 15 . Structuring the shapes can also take place in known manner. [0023] To the metal coating 17 is applied an insulating layer 19 with recesses 20 , which correspond in shape to the sensor elements 17 a , but are somewhat larger so as to surround the sensor elements like the frame cutouts 18 . The insulating layer 19 can be a plastic film, for example a polyester film. It can be self-adhesive on one or both sides so as to make it easier to produce the structure. [0024] A metal surface 25 is applied to the insulating layer 19 and can be constituted by a high-grade steel foil, a thin high-grade steel plate, etc., which more particularly when the surface is exposed so as to form the operating field 13 , can be cleaned and cared for in an advantageous, practical manner. [0025] At least in the vicinity of operating device 11 or operating fields 13 , the metal surface 25 has a uniform thickness throughout. In alternative constructions, a thicker metal layer or plate can be used and is thinned out over the operating fields 13 . [0026] A gap, filled with an air layer 22 , is formed between metal foil 25 and sensor element 17 a and is represented as an air filling by dotted lines. The air layer 22 forms a dielectric between the metallic operating field 13 and sensor element 17 a and its function will be described in greater detail hereinafter. In place of an air layer 22 as the dielectric, it is also possible to use some other dielectric, provided that it is compressible or can be compressed in order to bring the operating field 13 closer to the sensor element 17 a . This sag of the operating field 13 is illustrated in the vicinity of finger 14 by the downwardly curved broken line. [0027] A terminal 28 emanating from the downwardly projecting ends of the sensor elements 17 in FIG. 2 leads to the sensor element 17 a , for example for the control circuitry or evaluation circuitry of operating device 11 . The metal surface 25 , as illustrated in broken line form, can be connected to ground 29 . However, this may not be necessary, and if so, then there is only a capacitive coupling to sensor element 17 a or the surrounding surface 17 b of metal coating 17 . [0028] FIG. 4 shows a cooktop 31 , such as those incorporating a glass ceramic heating elements. In conventional manner, the latter has an all-round frame 33 , which is constructed on its left-hand, lower side as a front panel directed towards a user. The frame 33 has various operating fields 13 , namely to the far left, an ON-OFF switch and in the central area, a power adjusting switch for the individual hotplates and which are diagrammatically represented in circular form. Through pressure on the operating fields 13 it is possible to initiate the associated function for each heating element. In this construction, an operating device similar to that of FIG. 1 is located beneath the frame 33 . The surface of the frame 33 can be made from a metal coating, plate or foil throughout and corresponds to the metal surface 25 of FIG. 1 . As shown in FIG. 1 , the sandwich structure is only provided below the operating fields 13 . In the remaining area of the frame 33 , the metal can be solidly lined. [0029] Alternatively, the frame can be made from an metallic flat material that is several millimeters thick. The material may be thinned out from below in the vicinity of operating fields 13 and an associated operating device of FIG. 1 can be housed underneath in such thinned out areas. As an alternative to thinning out a thicker metal coating from below, there can also be a thinning out from above. In this case a resulting depression could be used as a structuring for a precise application of a finger or the like. [0030] In connection with the dimensions in FIG. 1 , it is pointed out that these can be varied. The thicknesses of the individual layers can be varied as advantageous for circuit board 15 . The metal coating 17 can be of various thickness, for example approximately 0.1 mm, such as is conventional for copper-coated circuit boards or the like. The insulating layer can also be 0.1 mm thick. The metal surface 25 above it has been used in tests with a thickness of 0.2 mm in the form of a high-grade steel foil and good results have been obtained. The exaggerated sag illustrated by the broken lines in FIG. 1 with respect to the metal surface 25 can be in the μm range, for example 10 μm or less. In the case of a test structure with a 0.2 mm thick high-grade steel foil as metal foil 25 , a weight of 230 grams gave rise to a sag such that it was possible to detect a capacitance change of 18% on sensor element 17 a . The surface of a sensor element 17 a or operating field is advantageously approximately 1 to 3 cm per side. This leads to a relatively well defined application surface, together with the resulting sag, on applying a finger 14 . [0000] Function [0031] Fundamentally, the operating device 11 according to the invention is based on the evaluation of a capacitive sensor element 17 a , a capacitance change resulting from the operation. An example of an evaluating circuit for such capacitive sensor elements, but in the case of a somewhat differently constructed sensor element, is known from EP 859 468 A. This evaluating circuit can also be used here in principle. [0032] Due to the compressive force on applying a finger 14 to operating field 13 , there is a certain sagging or deformation of the latter or of the associated metal surface 25 . This modifies the spacing between sensor element 17 a , which functionally represents a capacitor surface, and the metal surface 25 above it. This leads to a clear capacitance change on sensor element 17 a and said change can be detected and evaluated by the associated circuitry. As a result of the interposed dielectric 22 , the effect can be intensified by increasing the capacitance and in this way detection of the change is improved. [0033] Another advantage of determining the capacitance change as a relative change and not only as the absolute quantity, is avoiding false detections resulting as a function of any time-based downward sagging of the metal surface 25 and the resulting change to the absolute capacitance. [0034] Thus, the invention creates an operating device, which has a capacitive sensor element or capacitive operating principle. It is simultaneously possible to use particularly high-grade steel surfaces combined therewith on the operating fields for the operating device metal surfaces. These are particularly advantageous for practical reasons as such steel surfaces occur in numerous electrical appliances, particularly domestic appliances. Only a slight pressure with the finger is needed for operating purposes. In addition, very short operating paths are sufficient, but would not be sufficient as the switching path for mechanical switches.
An operating control device, such as for an appliance, is disclosed comprising sensor elements with a capacitive sensing function, the elements being located underneath a metallic surface that is used as the operating field. An insulating layer is situated between the elements and the metallic surface. When pressure is applied to the metallic surface the capacitance of the sensor element is altered by capacitive coupling. This alteration of capacitance can be determined by a corresponding evaluation circuit or the like for detecting activation of the device.
6
FIELD OF THE INVENTION The present invention relates to a method for producing a superstructure which is included in a tooth prosthesis system together with, inter alia, positioning members, drill guide sets, fixture guide sets and fixtures or fixture members, for example fixtures with associated spacer members, and securing members for anchoring the superstructure in the fixtures or fixture members, by means of which tooth prosthesis system a tooth prosthesis is intended to be applied (to a patient) at the time when, or a short time after, the fixtures have been applied (implanted) in the patient's jaw bone, for example on the same day or after just a few days. The superstructure can in this case be designed with a bearing part which can cooperate with the fixtures or fixture members, and a tooth-prosthesis-supporting part. The parts are designed with recesses through which the securing members extend upon said anchoring. The invention also relates to an arrangement in association with said superstructure. BACKGROUND OF THE INVENTION It is already known, for example from Swedish Patents 9602554-9 (506850) and 9602555-6 (506849), to provide such a tooth prosthesis system by means of which implantation and tooth prosthesis structuring can be executed in a very short time compared with the current times of 3 to 6 months. Reference is also made to the BR{dot over (A)}NEMARK NOVUM® system which is described for example in “Clinical Implant Dentistry and Related Research, Volume 1, Number 1, 1999” and the publication “Br{dot over (a)}nemark Osseointegration Center, May 99”. The concept is also described in the “Manual for Clinical Investigation 1999”. From the first-mentioned patent specification it is known to use a superstructure which expediently comprises a separate rail with securing members and a tooth prosthesis bridge which can be attached to the rail (see, for example, page 5, paragraph 4). The use of two matching upper and lower parts which are intended to bear against each other via a contact surface is also shown in detail in said “Manual”. SUMMARY OF THE INVENTION In the field of dentistry there is an urgent need to reduce the number of parts and components and at the same time to simplify techniques of producing and using said parts and components. There are a very large number of components on the market, and every successful attempt at implementing tried and tested and novel methods for effective treatment using a reduced number of components is seen as a step forward not only from the purely technical point of view, but also from organizational and economic points of view. When fitting a tooth prosthesis, it is essential to have access to components which are easy to adapt to different individuals, and in this respect it is important to have access to components and parts which are not critical from, for example, the point of view of structural height. It is also important to be able to make changes to the implantation method as such without adversely affecting the final result. It is important to be able to shorten the treatment time for the patient and thus eliminate certain intermediaries without adversely affecting the final result. It is also important to be able to improve the purely esthetic effect of the implanted tooth prosthesis. The main object of the present invention is to solve all or some of these problems. That which can principally be regarded as characterizing a method according to the invention is that the bearing part and the crown-supporting part are integrated over at least most of their horizontal extents, at the time of or in connection with the manufacture of the parts, by means of the parts being produced from a common blank or a material composition using a treatment or method which gives user-friendly outer shapes or bevels on the parts. In further developments of the inventive concept, it is proposed that, at the time of manufacture, the tooth-prosthesis-supporting part is given a shape which, in the horizontal cross section of the superstructure, is narrower than the bearing part, and that the parts are in this case formed with an outside transition which forms a curved or arc-shaped transition between the parts. Moreover, at its end surfaces which can cooperate with the fixtures or fixture members, the bearing part can be given depressions with plane bottom surfaces which are opposite the end surfaces of the fixtures or fixture members. The plane bottom surfaces of the depressions are given surface areas which exceed the surface areas of the fixtures or fixture members at the parts of the fixtures or fixture members cooperating with said bearing part. Moreover, at the time of its manufacture, the crown-supporting part can be provided with a number of holes extending in the transverse direction. Said parts can be made of titanium or another tissue-compatible material or tissue-compatible alloy. In a preferred embodiment, the parts are designed with a relatively low height, for example a height of between 0.5 and 1.0 mm, preferably between 0.7 and 0.8 mm. In one illustrative embodiment, the unit made up of said parts is produced by machining of a blank with subsequent grinding and/or barrel-polishing of sharp edges and production of outer bevels which give said user-friendliness. In a further embodiment, the unit forming the parts can be produced by casting material which can be sintered and solidified, and by subjecting it to a sintering procedure, and by subsequent working of the outer shape to give said user-friendliness. Moreover, at its front parts, the unit forming the superstructure can be provided or covered with material forming the tooth prosthesis, for example acrylate or another synthetic material normally used in tooth prostheses. The recesses for the securing members can have diameters which are only slightly less than the width of the tooth-prosthesis-supporting part. At the time of its production, the unit forming the superstructure can be given an arc shape and, at the ends of the arc shape, there are parts with a first bevel which is arranged on the bearing part and which via a curved part merges with the lower surface of the tooth-prosthesis-supporting part, which in turn is curved up toward the outer edge of the tooth-prosthesis-supporting part via a second bevel. That which can principally be regarded as characterizing an arrangement according to the invention is set out in the characterizing clause of the attached independent arrangement claim. Embodiments of the arrangement are set out in the subclaims linked to said independent claim. By means of what is proposed above, which runs counter to the avenues already followed in the prior art and thus opens up new approaches in this field, it is possible to eliminate an intermediate stage in the treatment by omitting the mutual relating and adapting of two cooperating parts. The material-working time in machine-working or “milling” of a blank can be substantially reduced and rendered less expensive. Considerable freedom of choice of the structure of the components can be allowed, and user-friendly and esthetically pleasing tooth prostheses can be obtained. BRIEF DESCRIPTION OF THE DRAWINGS A presently proposed embodiment of a method and of an arrangement according to the invention will be described below with reference to the attached drawings, in which: FIG. 1 shows, from the rear and in partial cross section, a superstructure and three implants or fixtures set in relation to it, with spacer members, securing screws for anchoring the superstructure in the implant, and areas of dentine, for example in the lower jaw of a human, FIG. 2 shows, in a perspective view obliquely from above right/from the rear, the superstructure with the implants/fixtures and the securing screws according to FIG. 1 , FIG. 3 shows, in a horizontal view from above, the superstructure in one structural illustrative embodiment, FIG. 4 shows the superstructure according to FIG. 3 from the inside and in a side view, FIG. 5 shows the superstructure according to FIGS. 3 and 4 from below, FIG. 6 shows the superstructure according to FIG. 4 from the side, FIG. 7 shows said superstructure in cross section along A—A in FIG. 6 , FIG. 8 shows the superstructure from the side and slightly turned in relation to FIG. 6 , FIG. 9 shows the superstructure in a perspective view, obliquely from above left, FIG. 10 , in cross section along B—B in FIG. 5 , shows the design of the bearing part and the crown-supporting part at one of the recesses for the securing members, and FIG. 11 shows the cross section of the unit along C—C in FIG. 5 . DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS In FIG. 1 , a superstructure is shown by 1 . The superstructure comprises a tooth-prosthesis-supporting part 1 a , and a bearing part 1 b which can cooperate with fixtures 2 , 3 and 4 . The parts 1 a and 1 b form a common unit, integrated along the greater part of their imaginary surfaces facing each other, cf. the surfaces of the separate parts according to the prior art. Each fixture is built in a manner known per se and can comprise an implant part which is provided with a thread 2 a , by means of which the implant or fixture can be screwed down into a hole in partially indicated dentine (jaw bone) 5 , preferably the lower jaw of a patient. The hole in the jaw bone is indicated by 5 a in FIG. 1 . At its upper end, the fixture or implant screwed down into the actual dentine or jaw bone has a spacer member which, in the incorporated state of the implant, is intended to extend above a jaw bone surface 5 b . The implant can be of the self-tapping type, and for examples of implants reference can be made to Swedish patent application 9900822-9 with date of filing Mar. 9, 1999. The upper end of the implant or the spacer member 2 b has a plane end surface 2 c. The bearing part 1 b is provided with depressions 1 c with plane bottom surfaces against which the upper surfaces 2 c of the implants are intended to bear. The unit 1 can be anchored in the implant by means of anchoring screws 7 , 8 and 9 . The anchoring screws extend in recesses 1 d through the unit 1 and each implant or spacer member is provided with a thread 2 d , in which the respective screw or in which the respective anchoring member 7 , 8 or 9 can be anchored. This anchoring is therefore done in a manner known per se. The upper part 1 a is provided with a number of through-holes 1 f which extend in the transverse direction of the upper part and which are used for holding the tooth-prosthesis-supporting part 1 a , as is symbolically indicated by 10 . On its upper side, each implant or each spacer member is provided with a hexagon 2 e which is arranged to protrude into a recess 1 e with a shape corresponding to the hexagon or with a shape locking the hexagon. The hexagon 2 e can be of another shape. The tooth prosthesis material 10 can be designed with a part 10 a which extends well above and covers both the part 1 a and the part 1 b , thus affording advantages from the esthetic point of view. FIG. 2 is intended to show the design or curve of the superstructure in a horizontal plane, which design or curve is arc-shaped and has an arc shape or curve following the curvature of the symbolically indicated dentine 5 . The figure shows the application of the implants 2 , 3 and 4 and the securing screws 7 , 8 and 9 in said arc shape. In FIG. 3 , the superstructure is shown with its parts 1 a and 1 b , from which it will be seen that the part 1 a has a narrower design than the part 1 b . In the example shown, the arc shape is substantially circular and the center is indicated by 11 . A radius r to the outer edge of the part 1 b is of the order of size of 23 mm. A radius r′ to the circular center line of the parts 1 a and 1 b is of the order of size of 20 mm. A radius r″ to the arc-shaped inner edge of the lower part is chosen at about 17 mm. The radii r′″ and r″″ to the arc-shaped outer and inner sides, respectively, of the part 1 a are chosen at about 21 mm and 18 mm, respectively. In the horizontal plane shown, the distances L, L′ between the securing member recesses 1 d are chosen at about 14.75 mm. A distance d in the radial direction between the recesses is chosen at about 6.5 mm. In FIG. 3 , a first angle α has been indicated for the radius R from the rearward/inward narrowing of the part 1 b . Said narrowing starts at a value of about 140° at said angle α. Said start of narrowing at the radii R is related to the inner surface of the part 1 b . A narrowing is also present for the outer surface of the part 1 b and the last-mentioned narrowing starts at a greater angle α (not shown in the figure for reasons of clarity). In FIG. 4 , the height of the superstructure is indicated by H. This height can be between 5 and 8 mm, for example about 6.5 mm. FIG. 4 also shows the size of the depression 1 c , or rather a height h between an underside 1 g of the superstructure and a bottom surface of the respective depression. Dimension h is about 0.5 mm less than the height H. The bottom surface of the depression 1 c has a surface area 1 which exceeds the corresponding surface area of the surface 2 c of the implant concerned (cf. FIG. 1 ). In FIG. 5 , the depressions 1 c on the part 1 b are shown from below. The surface area extents 1 are again shown. As will be seen from the figure, the surface area of the depressions is narrower at the inner surface of the part 1 b than at the outer surface of the same part. FIG. 5 also shows that, at said radius R, the part 1 b merges at its ends into a narrowed shape, in the horizontal section according to FIG. 5 , toward the points 1 b ′ and 1 b ″ of the superstructure. The total depth of the superstructure is indicated by D and is chosen at about 25.7 mm. FIG. 6 shows the positions of the holes 1 f on the part 1 a , a distance d′ between the lower surface 1 g and the center line 1 k of the hole having been chosen at about 1.5 mm. FIG. 7 shows the mutual relationships of the holes and their relationship to the central recess 1 d. The angle between the recess 1 d and each through-hole is indicated by means of the angles α″ which can be chosen at about 35°. The distance between the inner transverse holes and the recess 1 d is indicated by the angles α′″ and in the present case has been chosen at about 15°. The parts 1 a and 1 b are also indicated in this case. FIG. 8 shows the terminal transition between the parts 1 a and 1 b at the ends 1 b′ and 1 b″ . Said transitions are characterized by a first phase 11 , 11 ′ which merges into a curved transition part or 12 , 12 ′ and is thereafter finished by a further upswing phase 13 , 13 ′. FIG. 9 shows said phases (although not marked in the figure) at said ends 1 b ′ and 1 b″. FIGS. 10 and 11 show in detail the cross sections of parts 1 a and 1 b . The part 1 a has a width of about 2.8 mm in the depth direction which is indicated by A. The width or depth of the part 1 b is indicated by A′ and is chosen at about 5.5 mm. The part 1 b at the hole or recess 1 d of the securing member is indicated by 1 h ′ and assumes a value of about 3 mm. The corresponding height h″ at the position alongside the hole 1 d , i.e. the position according to FIG. 11 , assumes values of about 3.2 mm. FIG. 11 also shows the outside transitions 1 l , 1 l ′. Said transitions are arc-shaped or curved. FIG. 8 too shows the transition 1 l. The superstructure can be used in combination with positioning members, drill guide sets and fixture guide sets of the type shown in Swedish patent specification 9602554-9 (506850) mentioned at the outset. These members are therefore not described in detail here, but reference is made to the embodiments according to said patent. The superstructure can be produced by means of machining equipment in the form of milling members. After milling, the milled superstructure is surface-treated, for example by grinding equipment. Such equipment is already well known. Alternatively, a material composition or a material powder can be introduced into a mold for casting the superstructure. The superstructure thereby formed in the mold is sintered in an oven or can be made of a material that can solidify. The production equipment can in this case too consist of types known per se and will therefore not be described in detail here. By means of the above embodiment of the superstructure, the latter does not therefore have to take part in the covering function for the implants implanted in the dentine or jaw bone, and instead these implants or their ends can be exposed or uncovered during tooth prosthesis application to the unit forming the superstructure. This function affords the considerable advantage that adjustment between two different parts does not need to take place and that the covering function for the implant ends is not itself necessary in accordance with the proposal of the invention. According to FIG. 1 , the front parts of each implant in accordance with the above have cutting edges 2 f which provide a direction-stabilizing function during screwing into the dentine, irrespective of any inhomogeneity of the latter. The design and function of the cutting edge are described in the abovementioned patent application. The invention is not limited to the embodiment described above by way of example, and instead it can be modified within the scope of the attached patent claims and the inventive concept.
A superstructure is included together with other components in a tooth prosthesis system, by means of which a tooth prosthesis is intended to be applied to a patient in a short application time, for example in one or only a few days. The superstructure ( 1 ) is designed with a bearing part ( 1 b ) which can cooperate with fixture members, and a tooth-prosthesis-supporting part, and the parts are designed with recesses for said securing members. The bearing part and the tooth-prosthesis-supporting part are integrated over at least most of their horizontal extents by means of the parts being produced from a common blank or a material composition using a treatment or method which gives a user-friendly outer shape and bevels on the unit or superstructure forming the parts.
0
PRIORITY [0001] This application claims priority to U.S. Provisional Application No. 61/217,899, filed Jun. 5, 2009, which is incorporated by reference herein in its entirety. BACKGROUND [0002] Hydraulic fracturing uses fluid additives such as slickwater additives. The demand for this type of well services has increased over the past decade, especially because of its successful application for shale gas. Horizontal wells are often standard, requiring as much as 4.2 million gallons of water per well in as many as 6 to 9 fracture stages. Because of environmental concerns and fresh water availability, the flowback and produced water are collected and used for subsequent fracture treatments. Produced water is a perfect environment for sulfate reducing bacteria (SRB) and acid forming bacteria (AFB) due to its anaerobic nature (<2 ppm oxygen content) and high nutrient content (organics, free iron, etc.). Reuse of water introduces enough oxygen through regular pumping operations to allow aerobic bacteria to grow—mostly slime forming bacteria (SFB). The oxygen content is high enough for aerobic bacteria to grow but too low to kill anaerobic bacteria. The oxygen content will cause the anaerobic bacteria to stay in a biostatic state which does not kill them but prevents them from multiplying. [0003] As soon as the bacteria find an environment that is conducive to their growth, they will become active again and start multiplying. The anaerobic environment in the formation is ideal for growth of bacteria like SRBs and AFBs. The aerobic environment of the wellbore is conducive for SFBs. The growth of SRBs will not only lead to health and safety concerns due to increased sour gas or hydrogen sulfide (H 2 S) production but also to a slow souring of the reservoir. This also increases operation expenses because of corrosion (H 2 S pitting, stress cracking, etc.) in surface and subsurface tubulars. Other challenges in production can be related to AFBs (pitting) and SFBs (emulsion like materials may form). [0004] Various different methods can be applied to prevent bacteria growth and reduce operational expenses related to corrosion prevention, remediation of corrosion effects, and remediation of emulsion-like produced fluids. Common biocides are quaternary amines, glutaraldehyde, tetra-kis-hydroxylmethylphosphonium sulfate, and tetrahydro 3,5-dimethyl-1,3,5-thiadiazinane-2-thione. The issues with traditional non-oxidizing biocides like those described above are that they each have compatibility issues with common additives in stimulation fracturing treatments (e.g. quat amines are not compatible with quaternary and zircontate crosslinked fluids fluids or anionic friction reducing polymers) and that they are very toxic. Despite the treatment of water with these biocides, post-fracture treatment reservoir souring has been reported. The re-growth of SRB under reservoir conditions may lead to reservoir souring. An effective, low cost biocide that is compatible with other fluid additives and that is easily transportable is needed. FIGURES [0005] FIG. 1 is a bar graph of free active chlorine as a function of hydrochlorous acid concentration for three time periods. [0006] FIG. 2 is a bar graph of bacterial population as a function of time for three types of bacteria when a fluid comprises a friction reducer. [0007] FIG. 3 is a bar graph of bacterial population as a function of time for three types of bacteria when a fluid comprises a biocide. [0008] FIG. 4 is a bar graph of bacterial population as a function of time for three types of bacteria when a fluid comprises a hypochlorous acid. [0009] FIG. 5 is a photograph comparing produced water before and after addition of hypochlorous acid. [0010] FIG. 6 is a chart illustrating the percent drag reduction as a function of rate that compares a fluid comprising a viscosity modifying agent with and without hypochlorous acid. [0011] FIG. 7 is a chart illustrating viscosity as a function of time for the fluid identified by Table 2 and varied concentrations of hypochlorous acid. [0012] FIG. 8 is a chart illustrating viscosity as a function of time for the fluid identified by Table 3 and varied concentrations of hypochlorous acid. [0013] FIG. 9 is a chart illustrating viscosity as a function of time for the fluid identified by Table 4 and varied concentrations of hypochlorous acid. [0014] FIG. 10 is a chart illustrating viscosity as a function of time for the fluid identified by Table 5 and varied concentrations of hypochlorous acid. [0015] FIG. 11 is a schematic view of mechanical equipment configured to perform an embodiment of the invention. [0016] FIG. 12 is a chart illustrating bacterial population as a function of types of bacteria in a field trial comparing the microbe content of fresh water, produced water, mix water, mix water and hypochlorous acid, and flowback water and acid after 21 days. [0017] FIG. 13 illustrates viscosity as a function of time for a guar fluid that contains no sodium hypochlorite and two different concentrations of sodium hypochlorite. [0018] FIG. 14 shows titration curves for addition of sodium diacetate buffer to various solutions of concentrated industrial sodium hypochlorite in tap water. [0019] FIG. 15 shows titrations of some produced water samples treated with sodium hypochlorite (0.21 gpt) and one sample of tap water that was pre-acidified using citric acid prior to treatment with concentrated industrial sodium hypochlorite. [0020] FIG. 16 shows drag reduction in a 0.5″ pipe using 0.25 gpt friction reducer, versus water. [0021] FIG. 17 provides friction reduction curves at 0, 15, and 30 minutes. SUMMARY [0022] Methods and apparatus of embodiments of the invention relate to a system for treating a subterranean formation including mixing equipment to form a fluid comprising sodium hypochlorite and sodium diacetate; and pumps and a tubular to introduce the fluid into the subterranean formation, wherein a surface of the subterranean formation contains at least 15 percent less microorganisms than if no sodium hypochlorite were in the fluid. Methods and apparatus of embodiments of the invention relate to a method of producing a petroleum product from a wellbore including using a well treatment system comprising mixing equipment, pumps, and a tubular, forming a fluid comprising sodium hypochlorite and sodium diacetate; and introducing the fluid to the well treatment system to achieve a reduced population of microorganisms in the system. Methods and apparatus of embodiments of the invention relate to a system, comprising: a subterranean formation, a well treatment apparatus comprising mixing equipment, pumps, and a tubular, and a fluid comprising sodium hypochlorite and sodium diacetate to achieve a reduced population of microorganisms in the system. Methods and apparatus of embodiments of the invention relate to a method for treating a subterranean formation, comprising forming a fluid comprising sodium hypochlorite, a buffer, and a polymer; introducing the fluid to a surface of a subterranean formation; and decreasing a population of microorganisms, wherein the surface of the subterranean formation contains at least 15 percent less microorganisms than if no sodium hypochlorite were in the fluid, and wherein the fluid exhibits a pH of about 4.0 to about 7.5. Methods and apparatus of embodiments of the invention relate to a method for treating a subterranean formation, comprising forming a fluid comprising sodium hypochlorite and sodium diacetate; and introducing the fluid to a subterranean formation, wherein forming the fluid does not include introducing an acid, and wherein forming the fluid does not include forming a precipitate. DETAILED DESCRIPTION [0023] At the outset, it should be noted that in the development of any such actual embodiment, numerous implementation-specific decisions must be made to achieve the developer's specific goals, such as compliance with system related and business related constraints, which will vary from one implementation to another. Moreover, it will be appreciated that such a development effort might be complex and time consuming but would nevertheless be a routine undertaking for those of ordinary skill in the art having the benefit of this disclosure. The description and examples are presented solely for the purpose of illustrating the preferred embodiments of the invention and should not be construed as a limitation to the scope and applicability of the invention. While the compositions of the present invention are described herein as comprising certain materials, it should be understood that the composition could optionally comprise two or more chemically different materials. In addition, the composition can also comprise some components other than the ones already cited. [0024] In the summary of the invention and this description, each numerical value should be read once as modified by the term “about” (unless already expressly so modified), and then read again as not so modified unless otherwise indicated in context. Also, in the summary of the invention and this detailed description, it should be understood that a concentration range listed or described as being useful, suitable, or the like, is intended that any and every concentration within the range, including the end points, is to be considered as having been stated. For example, “a range of from 1 to 10” is to be read as indicating each and every possible number along the continuum between about 1 and about 10. Thus, even if specific data points within the range, or even no data points within the range, are explicitly identified or refer to only a few specific, it is to be understood that inventors appreciate and understand that any and all data points within the range are to be considered to have been specified, and that inventors have disclosed and enabled the entire range and all points within the range. [0025] Embodiments of the invention relate to the use of sodium hypochlorite as an effective biocide in combination with sodium diacetate for use in operations related to recovering hydrocarbons from subterranean formations, such as fracturing operations, especially those fracturing operations that use fluid additives for viscosity modification. That is, embodiments of this invention relate to the use of sodium hypochlorite and sodium diacetate for killing and managing microbes in water used for fracturing including slickwater fracturing. In some embodiments, hypochlorous acid can be delivered in a dilute and stable form, such as by using EXCELYTE™ composition, which is commercially available from Benchmark of Houston, Tex. Calcium hypochlorite may be selected for some embodiments. It also will form hypochlorous acid upon exposure to water. Hypochlorous Acid [0026] Generally, when chlorine is added to water, hypochlorous acid is formed according to the equation: [0000] Cl 2 +H 2 HOCl+HCl [0027] Hypochlorous acid has outstanding bactericidal power. This is generally attributed to its ability to diffuse through cell walls and thereby reach the vital parts of the bacterial cell. A widely accepted theory credits the death of the cell to a reaction between hypochlorous acid and enzyme. The hypochlorite ion has little if any bactericidal effect since its negative charge impedes penetration of the cell wall. [0028] The bactericidal power of a solution of chlorine, a hypochlorite, or a chloramine is directly proportional to the hypochlorous acid concentration of the solution. The percent available chlorine as un-dissociated hypochlorous acid is therefore the true measure of the bactericidal effectiveness of a solution containing one of the chemicals of the available chlorine family. [0029] The available chlorine family is comprised of the group of chemicals which, when dissolved in water, yield solutions of hypochlorous acid. These compounds may be further subdivided into those which contain free available chlorine and those which contain combined available chlorine. [0030] Oxidizing power of a hypochlorite and/or hypochlorous acid solution is attributable to the amount of active oxidant, measured as Free Available Chlorine (FAC), irrespective of pH. Organic chloramines are also a source of FAC, where the low rate of hydrolysis of dissolved organic chloramines to give hypochlorite and/or hypochlorous acid contributes little to the rate of oxidation while maintaining the total oxidizing power, which relates to the amount of organic chloramines present. Thus, organic chloramines and other reagents that contribute to FAC supply more hypochlorite and/or hypochlorous acid as these oxidizers are depleted. [0031] Hypochlorous acid is 25 to 100 times more effective than bleach as a disinfectant without being corrosive. The key active ingredient, hypochlorous acid, is a naturally occurring molecule synthesized from an electrolyzed solution of salt and water. When exposed to atmospheric conditions, it quickly degrades into saltwater, therefore not leaving ecological damage at field locations. [0032] Hypochlorous acid does not fully dissociate and has a neutral pH. (around 7.5). In aqueous solutions, hypochlorous acid partially dissociates into a salt (the hypochlorite ion), therefore its use in oil field service application does not leave an undesirable ecological footprint. In contrast, the most commonly used oxidizers do not sterilize and completely kill bacteria. Hypochlorous acid, on the other hand, reacts quickly with any organic-based or readily oxidizable materials (Fe, H 2 S) present in the water. Further, hypochlorous acid is noncorrosive compared to other biocides. [0033] In some embodiments, hypochlorous acid will have a concentration of about 1 to 8,500 ppm in a fluid. The pH of hypochlorous acid influences the free available chlorine concentration. The relationship between pH and the degree of dissociation acid is illustrated by Table 1. Hydrolysis increases rapidly as the pH rises above neutrality. [0000] TABLE 1 Dissociation of Hypochlorous Acid as a Function of pH at 25° C. pH % HOCl Undissociated 5.0 99.6 6.0 96.5 7.0 73.0 7.4 50.0 8.0 21.0 9.0 2.7 10.0 0.3 [0034] Hypochlorous acid may be commercially manufactured using several methods. In some embodiments, hypochlorous acid may be made by exposing water containing sodium chloride to an electrolytic cell. It can also be made in a more concentrated form in the field by using a buffer, such as sodium diacetate, to lower the pH of a sodium hypochlorite solution in water. Finally, in some embodiments, hypochlorous acid may be generated by dissolving chlorine gas in water. [0035] Hypochlorous acid can also be formed by introducing sodium hypochlorite into a solution that has a pH that can be synthesized from an electrolyzed solution of salt and water, or generated by lowering the pH of a hypochlorite solution to a pH below 7.5, often tailored to have a pH of 4 to 7. For example, a continuous process that includes continuous addition of sodium hypochlorite and pH modifying agent such as a weak acid such as on the fly mixing in oil field service applications may be selected. PH modifying agents such as weak acid, a buffer and/or a strong acid may be used to tailor the pH. In some embodiments, the preferred pH modifying agent may comprise water-soluble organic acids with twelve or fewer carbon atoms. The weak acid is an acid that exhibits a pKa of less than 6. Weak acids include potassium dihydrogen phosphate, phthalic acid, phthalates such as potassium hydrogen phthalate and related acid salts, chelates, citric acid, sulfamic acid, ascorbic acid, octanoic acid, nonanoic acid, propionic acid, erythorbic acid, succinic acid, glutaric acid, adipic acid, polyacrylic acid, maleic acid, cyanuric acid, orthophosphoric acid, acetic acid, and sodium, potassium, and calcium salts of these acids. A weak acid, a buffer, or a combination thereof may be used to tailor the pH. In some embodiments, the preferred weak acid may comprise water-soluble organic acids with twelve or fewer carbon atoms. The preferred weak acid exhibits a pKa of less than 6. [0036] In some embodiments, a pH modifying agent may include a strong acid that does not contain a halogen, such as sulfuric, nitric, or phosphoric acid may be used in very dilute concentration, such as nanomolar concentration. Other buffers, buffer solutions, or buffer systems may be selected. [0037] The pH modifying agent may be selected to activate upon the passage of time or temperature, such that the hypochlorous acid is present in solution after the solution containing sodium hypochlorite and pH modifying agent is pumped into a wellbore. Generally, however the hypochlorous acid is manufactured, the pH modifying agent may be selected to modify the pH of the fluid over a tailored time or temperature. Agents most likely to be effective include polylactic acid, polyglycolic acid, or similar hydrolytic polyesters. Delay may be enhanced by isolating the agent in an oil phase and the sodium hypochlorite in the water phase in some embodiments, the acid may be encapsulated. Upon temperature and downhole mixing, delayed formation of hypochlorous acid may be achieved. Fumeric acid encapsulated in wax may also be selected. [0038] However the hypochlorous acid is formed, to maintain the hypochlorous acid concentration within a fluid, the fluid may be tailored to exhibit a pH of 4.0 to 7.5 using a buffer or weak acid. In some embodiments, the preferred weak acid may comprise water-soluble organic acids with twelve or fewer carbon atoms. A weak acid is an acid that exhibits a pKa of less than 6. Weak acids include potassium dihydrogen phosphate, thallic acid, phthalates, chelates, citric acid, sulfamic acid, ascorbic acid, octanoic acid, nonanoic acid, propionic acid, erythorbic acid, succinic acid, glutaric acid, adipic acid, polyacrylic acid, maleic acid, cyanuric acid, orthophosphoric acid, acetic acid, and sodium, potassium, and calcium salts of these acids. In some embodiments, a strong acid that does not contain a halogen, such as sulfuric, nitric, or phosphoric acid may be used in very dilute concentration, such as nanomolar concentration. Other buffers, buffer solutions, or buffer systems may be selected. [0039] Additional chemicals may be added to a hypochlorous acid composition to stabilize the hypochlorous acid concentration and/or to reduce the reactivity of the bacteria's residual enzymes. Dichloroisocyanuric acid, cyanuric acid, sulfamic acid, potassium iodate, ethylenediaminetetraacetic acid, or a combination thereof may be selected for some embodiments. [0040] The method can also include contacting the aqueous medium with an enzyme activity minimizer including a metal. In an embodiment, the metal can include a heavy metal compound in the aqueous medium including oilfield produced water. In an embodiment, the heavy metal can include zirconium compound. Zirconium containing chemicals may be used to reduce the reactivity of residual bacteria enzymes. Examples of zirconium containing chemicals that act as enzyme activity minimizer include zirconium nitrate, zirconyl chloride, zirconium phosphate, zirconium potassium chloride, zirconium potassium fluoride, zirconium potassium sulfate, zirconium pyrophosphate, zirconium sulfate, zirconium tetrachloride, zirconium tetrafluoride, zirconium tetrabromide, zirconium tetraiodide, zirconyl carbonate, zirconyl hydroxynitrate, zirconyl sulfate, zirconium complexed with amino acids, zirconium complexed with phosphonic acids, hydrates thereof and combinations thereof. Organo-zirconium compound examples include zirconium acetate, zirconyl acetate, zirconium acetylacetonate, zirconium glycolate, zirconium lactate, zirconium naphthenate, sodium zirconium lactate, triethanolamine zirconium, zirconium propionate, hydrates thereof and combinations thereof. Zirconium dichloride oxide may be selected for some embodiments. Other Fluid Additives [0041] The carrier fluid, such as water, brines, or produced water, may contain other additives to tailor properties of the fluid. Rheological property modifiers such as friction reducers, viscosifiers, emulsions, stabilizers, solid particles such as proppant or fibers, or gases such as nitrogen may be included in the fluid. The fluid may include viscosity modifying agents such as guar gum, hydroxyproplyguar, hydroxyelthylcellulose, xanthan, or carboxymethylhydroxypropylguar, diutan, chitosan, or other polymers or additives used to modify viscosity for use in the oil field services industry. Water based fluids may include crosslinkers such as borate or organometallic crosslinkers. In some embodiments, the fluid may contain viscosity modifying agents that comprise viscoelastic surfactant. Viscoelastic surfactants include cationic, anionic, nonionic, mixed, zwitterionic and amphoteric surfactants, especially betaine zwitterionic viscoelastic surfactant fluid systems or amidoamine oxide viscoelastic surfactant fluid systems. Applications [0042] The fluid may be used as a fracturing fluid, drilling fluid, completions fluid, coiled tubing fluid, sand control fluids, cementing operations fluid, fracturing pit fluid, or onshore or offshore water injector fluid, or any other fluid that is introduced into a subterranean formation primarily for the recovery of hydrocarbons. The fluid is introduced to the subterranean formation by drilling equipment, fracturing equipment, coiled tubing equipment, cementing equipment, or onshore or offshore water injectors. During, before, or after the fluid is added to a subterranean formation, the formation may benefit from fracturing, drilling, controlling sand, cementing, or injecting a well. [0043] An oil field services application of a hypochlorous acid fluid may include delivery of the fluid to the following mechanical equipment. Hypocholorous acid fluid may be delivered to the low pressure side of the operation, that is, into any low pressure hose, connection, manifold, or equipment; before or during treatment. Examples of the location for addition include into pond, pit, or other water containment source; into inlet hose/manifold of water tanks (upstream of water tanks); frac tanks—all together or separate; into water tanks (frac tanks) themselves; into hose/manifold of outlet side of water tanks; into batch mixing unit; into hose/manifold in between batch mixing unit and blender; into blender itself; into exit side of blender (upstream of fracturing pumps); hose/manifold; directly into low pressure side of pump manifold (missile). Hypochlorous acid fluid may be delivered to the high pressure side of an operation including into any high pressure iron, anywhere. Pumps that may be used, either solo or combined, include positive displacement pumps, centrifugal pumps, and additive pumps. The hypochlorous acid fluid may be added to the water stream in any way. (i.e. pour from a bucket, pump it into the water, etc.). [0044] FIG. 11 is a schematic view of mechanical equipment configured to perform an embodiment of the invention. Working tanks 1101 contain water or liquid that is introduced to water line 1102 . Water line 1102 may include an entry port 1103 for acetic acid or sodium diacetate or other pH controlling agent. The entry port 1103 includes a connection to the pH control agent line 1104 which is connected to additive skids 1105 , which may be any type of pump or other delivery device. The line 1104 may include acetic acid, sodium diacetate, or other pH controlling agent or any other chemical. The skids 1105 are controlled, in part, by feedback from a control device 1106 as illustrated by lines 1107 . The water line 1102 is also in communication with a pH meter or other online or offline sampling entity 1108 which may be used to determine the pH or other property of the water as it enters water line 1102 . The entity 1108 sends a signal via a line 1109 or using a transmitter that does not require lines to a pH meter 1110 or other property measurement device which sends a signal to the control device 1106 via lines 1111 or using a transmitter that does not require lines. The entities 1108 and 1112 may be any type of probe such as an electrode. The pH meter 1110 also collects information from pH meter or other online or offline sampling entity 1112 via line 1114 or using a transmitter that does not require lines which is connected to a blender 1113 . The pH meter 1110 sends a signal via line 1115 or using a transmitter that does not require lines to the control device 1106 . In any event, as the water or liquid flows through line 1102 , it continues on into the blender 1113 where additional chemicals are introduced via line 1116 , which delivers sodium hypochlorite and/or other biocide and/or any other relevant chemical. The delivery of sodium hypochlorite is, in part, controlled by the skids 1105 , which receive a signal from the controller 1106 via lines 1117 or using a transmitter that does not require lines. The fluid flows from the blender 1113 on to the manifold 1118 via lines 1119 or using a transmitter that does not require lines, then on to the wellbore through the pumps or other lines or other equipment of the manifold 1118 and on to tubulars or other wellbore equipment. [0045] In some embodiments, the pH control or component concentration control of the system may be performed using an electronic control system as described above. In some embodiments, manual control may be used, including measuring the pH and/or composition of the water in the tanks 1101 or the line 1102 or the line 1119 . In some embodiments, no pH metering may be performed at all and the concentration of components may be established based on volume of material. In some embodiments, a hybrid manual/electronic control system may be used with sampling and addition partially manually controlled, partially electronically controlled. In some embodiments, addition of one component may be using the skids 1105 described above or using equipment configured for addition at other points in the blender, line 1119 , or in the manifold. In some embodiments, the controller 1106 and/or pH meter 1110 and/or skids may be the same piece of equipment. In some embodiments, the controller 1106 and/or pH meter 1110 may be omitted altogether, especially if the volume of material is fixed. In some embodiments the blender 1113 may be a blender, a tubular, a line, a static mixer, or any other equipment that may provide static or agitated mixing or blending. In some embodiments, the order of mechanical equipment including mixing, blending, introducing components, measuring pH may be altered. Further, the control system may be configured in alternative ways to accommodate changes in the mechanical equipment. [0046] In some alternative embodiments, delivering the components to form the hypochlorous acid fluid to the mechanical equipment in the field must be selected based on the source of the acid. Commercially available hypochlorous acid, such as EXCELYTE™, is delivered premixed into any size storage containers. It may be added to the system with any way into any of the above points of addition. Sodium hypochlorite may be combined with a weak acid on the fly or by batch mixing. In on the fly applications, the material may be added by separate add lines—one for sodium hypochlorite, one for acid/buffer (any order); by a combined system—concentrated mixture of sodium hypochlorite and acid/buffer; or by a slurry system—combined mixture of water, sodium hypochlorite and acid/buffer. In batch mixing applications, the components may be mixed together before or during the fracturing job and stored in any type of container. It may be added to the system with any way into any of the above points of addition. In some embodiments, hypochlorous acid may kill or retard the reproduction of microorganisms. In some embodiments, hypochlorous acid in the fluid will result in a fluid with at least 25 percent less microorganisms or at least 25 percent less bacteria than if no hypochlorous acid were present. EXAMPLES [0047] The following examples are presented to illustrate the preparation and properties of fluid systems, and should not be construed to limit the scope of the invention, unless otherwise expressly indicated in the appended claims. All percentages, concentrations, ratios, parts, etc. are by weight unless otherwise noted or apparent from the context of their use. [0048] Several analytical tools were selected to confirm the effectiveness of hypochlorous acid, its compatibility with other fluid additives, and its stability over time with optional stabilizing additives. Water Quality—Water Analysis (Produced Water) [0049] The type of water used in these Examples, unless described otherwise, was produced water from the Piceance Basin, which is considered to be among the dirtiest, recycled, produced water with poor quality. The sample water was provided to us by a supplier and yielded a pH of 8.0 and a TDS of 142,000 ppm. Titrimetric methods were used to determine the anions present while Inductively Coupled Plasma spectrometry was used for the detection of cations in the sample water. Free Available Chlorine (FAC) Demand Test [0050] The chlorine exists in the water as hypochlorous acid (free available chlorine, FAC). Chlorine is effective against all microorganisms and any readily oxidizable organic matter. If there is a lot of organic matter in the fracturing water, the chlorine will be consumed (or spent) and will be unavailable for killing the bacteria. Therefore, it is necessary to have a residual of FAC in the water to be effective as a biocide. The FAC demand test determines the dosage of hypochlorous acid necessary to treat the water and kill the bacteria in the frac water. The FAC demand test was used to determine the dosage of hypochlorous acid necessary to treat and kill the bacteria downhole. The FAC of the sample water was determined at several time points up to 45 minutes using various concentrations of hypochlorous acid. 5% (v/v) of hypochlorous acid solution containing 500 to 1000 ppm active ingredient was found to be the lowest effective concentration that showed a positive FAC residual necessary to sanitize and kill the microorganisms present in the produced water. FIG. 1 shows data collected on a Piceance Basin water sample. As can be seen, 5% (v/v) or 50 gpt hypochlorous acid solution was the lowest effective concentration that showed a positive result of FAC residual which was necessary to sanitize and kill the bacteria. Consequently, 50 gpt hypochlorous acid solution was used as the concentration for all subsequent testing regarding hypochlorous acid. [0051] Bottle tests were used to evaluate the biocidal efficacy of hypochlorous acid against the three types of bacteria mentioned above as well as compare its performance with friction reducer and commonly used biocide, glutaraldehyde. The bacterial population was measured at time points up to seven days. Effect of Friction Reducer on Bacterial Population [0052] FIG. 2 shows the effect of a viscosity modifying agent, that is, a friction reducer has on biological activity. As can be seen that friction reducer had little or no effect on the bacterial population. 0.25 gal/Kgal polyacrylamide emulsion was added to the Piceance Basin water sample for a period of seven days to see its effect on the biological activity. The above figure shows that the friction reducer had little or no effect on the bacterial population. Effect of Gluteraldehyde on Bacterial Population [0053] FIG. 3 shows that glutaraldehyde is not very effective in killing bacteria in Piceance River water containing 0.25 gpt of friction reducer. Note a 2 log reduction in the population of SRB after 24 hours (a 3 log reduction is desirable). However, after 7 days there was re-growth of bacteria. 0.25 gal/Kgal glutaraldehyde was added to the produced water sample along with 0.25 gal/Kgal friction reducer to evaluate the effect of glutaraldehyde on bacterial activity for seven days. The above figure shows that glutaraldehyde in the presence of friction reducer was not effective in killing the bacteria in the water sample; however, there was a 2 log reduction in the SRB population after 24 hours. After seven days, regrowth of bacteria was apparent, suggesting the possibility of sour wells after fracturing treatment. Effect of Hypochlorous Acid on Bacterial Population [0054] FIG. 4 shows the hypochlorous acid is very effective in killing all bacteria in the Piceance River water. After 7 days, the bacterial counts were blow detectable limits and no regrowth was apparent. 5 (v/v) hypochlorous acid solution (500-1000 ppm active) was added to the produced water sample containing 0.25 gal/Kgal friction reducer to evaluate the effect of hypochlorous acid activity on bacterial activity for seven days. Within five minutes, the bacterial population was significantly reduced from 10 6 cells/mL to 10 1 cells/mL. After 24 hours, the SRB population was not detectable and regrowth was not apparent after seven days. [0000] Compatibility with Slickwater Additives and Piceance River Water [0055] Visual tests were performed to illustrate that there were no incompatibilities between viscosity modifying additives and hypochlorous acid solution (500-1000 ppm active). Also, bottle tests were performed. Bottle tests (deionized water and produced water) were performed with deionized water and produced water, separately. 5% (v/v) hypochlorous acid solution was added to a series of individual bottles with slickwater additives, including clay stabilizer, scale inhibitor, friction reducer and a microemulsion. The compatibility of hypochlorous acid solution and the slickwater additives were observed at time 0 and 5 minutes. No incompatibilities were observed between the slickwater additives and hypochlorous acid solution in deionized water. Before adding hypochlorous acid solution to the produced water, there was a strong rotten egg odor in the water sample indicating the presence of SRB. After the five minute treatment of hypochlorous acid solution, a color change was observed and the rotten egg odor was eliminated. Additionally, the pH remained stable for all fluids tested. FIG. 5 shows addition of hypochlorous acid to the produced water eliminated rotten odor and color changed to a lighter shade. The pH remained stable after the hypochlorous acid treatment. Apparently, the hypochlorous acid is very effective in improving the quality of produced water by oxidizing the contaminants. Effects of Hypochlorous Acid on Friction Reducer [0056] A friction loop consisting of a ½″ and a ¾″ pipe was used for drag reduction measurements. Synthetic water was prepared based on the water analysis of the Piceance Basin produced water sample. Fifteen liters of the source water, along with the slickwater additives and hypochlorous acid solution, were stirred using an overhead stirrer at 1000 rpm for two minutes before being added to the friction loop for evaluation. Before analysis, the differential pressure gauges were purged and the pump was primed prior to recording the data for the test. The test fluid was then pumped for about 10 seconds at incremental intervals of about 6 Kg/min and the percent drag reduction was calculated. The figure shows the friction loop results of the slickwater additives and hypochlorous acid measuring the percent drag reduction as a function of flow rate (Kg/min). Varying the viscosity modifying additives with and without hypochlorous acid shows no incompatibilities as illustrated by FIG. 6 . FIG. 6 shows the friction loop results of slickwater additives and hypochlorous acid. Data are plotted as the percent drag reduction as a function of flow rate (Kg/min). Hypochlorous acid had no effect on the slickwater additives. This shows that the viscosity difference due to the presence of the hypochlorous acid in about 2 percent or less. [0000] Hypochlorous Acid in Combination with Common Fracturing Fluids [0057] The compatibility of hypochlorous acid was evaluated with common fracturing fluids currently used in field operations. The hypochlorous acid solution was used at concentrations of 0 gal/Kgal, 10 gal/Kgal, and 50 gal/Kgal. The fluid compositions are listed in Tables 2-5. Fluids were tested at 150 deg F. for a period of one hour. The mixing procedure for the fracturing fluids is as follows: 500 mL of deionized water was placed into a Waring blending cup; subsequently, the hypochlorous acid solution was added and allowed to mix for 20 seconds. The gelling agent was then added and allowed to mix for 10 minutes, after which the linear gel viscosity was checked and compared to the hydration chart (see below). The remaining additives were then added to the solution and the vortex was allowed to close (after the addition of the crosslinker). Rheology profiles of the four fluids may be found in FIGS. 7 to 10 which illustrate the experimental results generated using the fluids of tables 2-5. The fluids did not result in a significant loss in viscosity when the hypochlorous acid solution concentration was increased from 0 gal/Kgal to 50 gal/Kgal. Additionally, the fluid is still viable and capable of transporting proppant. [0058] Common Fracturing fluids that may be utilized with hypochlorous acid are listed in the following tables. [0000] TABLE 2 Fluid formulation 1 Additive Concentration Tetramethyl 2 gpt ammonium chloride (TMAC) Slurried guar 6.25 gpt Borate crosslinker 3 gpt Hypochlorous acid 0, 10, 50 gal/Kgal solution (500-1000 ppm active) [0000] TABLE 3 Fluid Formulation 2 Additive Concentration Tetramethyl 2 gpt ammonium chloride (TMAC) Slurried guar 6.25 gpt Boric acid 5.5 ppt Sodium Hydroxide 10 ppt d-Sorbitol 2 gpt Hypochlorous acid 0, 10, 50 gal/Kgal solution (500-1000 ppm active) [0000] TABLE 4 Fluid Formulation 3 Additive Concentration Tetramethyl 2 gpt ammonium chloride (TMAC) Slurried guar 6.25 gpt Sodium Borate 1.3 gpt 30% Sodium 0.5 gpt Hydroxide Hypochlorous 0, 10, 50 gal/Kgal acid solution (500-1000 ppm active) [0000] TABLE 5 Fluid Formulation 4 Additive Concentration Polyvinyl acetate/ 6.7 gpt polyvinyl alcohol copolymer Erucic amidopropyl 40 gpt dimethyl betaine Hypochlorous acid 0, 10, 50 gal/Kgal solution (500-1000 ppm active) [0000] TABLE 6 Linear Gel Viscosities at Increased Biocide Concentrations Biocide Concentration Temperature (gpt) (F.) Viscosity (511, sec −1 ) 0 71.2 19 10 74.1 18.5 50 68.7 18 Stabilization of Hypochlorous Acid [0059] Using 100 mL of 3% (v/v) bleach, 29 mL of 5% (v/v) acetic acid was added to obtain a pH of 6.5 from an initial pH value of 8.48. The FAC residual was greater than 1000 ppm. Additionally, in a separate experiment, 22 mL of 1M sodium citrate was added to the bleach solution to obtain a pH of 6.5. The FAC value was then found to be 24 ppm. More details of this portion of the experimental data are presented below in paragraph 0061. [0060] Bottle tests were used to evaluate the stabilization of hypochlorous acid with the following chemicals: dichloroisocyanuric acid (DCCA) and cyanuric acid (CA). Cyanuric acid is known to stabilize the rate of decomposition of hypochlorous acid in ultraviolet conditions. Over a period of four days, a set of bottles with the following components were left open: 1) hypochlorous acid solution (500-1000 ppm active), 2) hypochlorous acid solution +30 ppm CA, 3) hypochlorous acid solution +50 ppm CA, 4) hypochlorous acid solution +30 ppm DCCA, and 5) hypochlorous acid solution +50 ppm DCCA. At the time of preparation, the initial pH and FAC were taken and recorded (see table below). The test points were then taken again after 1 day and four days. For all solutions prepared, the pH was stable (within 5% of the starting hypochlorous acid solution) after the addition of DCCA and CA. Additionally, the FAC residual value for all solutions decreased by 5%, with the DCCA-containing solutions obtaining a consistently higher FAC residual than hypochlorous acid solution alone. [0000] Time = 0 Time = 1 day Time = 4 days FAC FAC FAC pH (ppm) pH (ppm) pH (ppm) Hypochlorous acid 6.80 726 6.86 692 7.18 628 solution Hypochlorous acid 6.51 660 6.76 646 7.13 587 solution + 30 ppm CA Hypochlorous acid 6.47 670 6.77 637 7.16 580 solution + 50 ppm CA Hypochlorous acid 6.62 739 6.75 705 7.13 639 solution + 30 ppm DCCA Hypochlorous acid 6.79 739 6.99 705 7.20 639 solution + 50 ppm DCCA Hypochlorous Acid Solution Made from Sodium Hypochorite. [0061] A tank is filled with 400 gallons of city water. To this is added 20 gallons of 12% sodium hypochlorite solution. This result in a 0.6% solution of sodium hypochorite. To this is added an excess of citric acid until the pH of the resulting solution reaches pH equal to 6.5. This stock solution is then added on the fly to the fracturing treatment. The concentration of the stock solution added to the fracturing fluid was 0.2 to 0.6 gallons per thousand gallons. Using 100 mL of 1% (v/v) sodium hypochlorite (10000 ppm), 12.8 mL of 5% (v/v) acetic acid was added to obtain a pH value of 7.0 from an initial pH of 9.7. The active concentration (FAC residual) of the resultant solution was then found to be 8500 ppm. After one hour, the active concentration remained the same. In 24 hours, the active concentration decreased by 3.5% to 8210 ppm. Similarly, 55.2 mL of 0.1M succinic acid solution was added to 100 mL 1% (v/v) sodium hypochlorite to obtain a pH value of 7.0. The active concentration was found to be 6040 ppm after titration. [0062] A fracturing treatment using hypochlorous acid lasted two days. Four stages, at 2 hours per stage, were pumped using a total of 1.86 million gallons of water. 1.6M pounds of proppant were used. In total, 19 k gallons of hypochlorous acid solution (500-1000 ppm active) was pumped. The concentration of hypochlorous acid solution that was required (10 gpt) also required bulk storage and high rate additive pumps. A 12,000 gallon fluid module (modified frac tank) was placed next to the water frac tanks. An additive skid with 2 large Waukesha pumps, capable of 45 gpm, added hypochlorous acid at a rate of 42 gpm. Hypochlorous acid solution was pumped from the bulk module tank and into the 250 bbl batch mixing tank. [0063] In another field test, 26 gpt hypochlorous acid solution was added with 1 gpt slickwater fluid and mixed for less 1 min at 80 bbls/min to a form a fluid. To be precise, the pH of the fluid was 6. Thus, the 26 gpt hypochlorous acid was 2.5 percent active hypochlorous acid and 0.075 percent hypochlorite ion. FIG. 12 is a chart illustrating bacterial population as a function of types of bacteria in a field trial comparing the microbe content of fresh water, produced water, mix water, mix water and hypochlorous acid, and flowback water and acid after 21 days. That is, FIG. 12 illustrates the microbe population demise over time. All data points were taken on location. Initial flowback data was taken 21 days after job completion. The final flowback data point was taken 51 days after job completion. [0000] Sodium Diacetate in Combination with Sodium Hypochlorite [0064] Several tests were performed to illustrate how sodium diacetate works as a buffer for maintaining the pH and thus the integrity of the sodium hypochlorite. Titrations were performed using Eppendorf-style micropipettors to dispense sodium diacetate into 100 ml fluid samples contained in glass jars. The mixture was continuously stirred at medium shear by a 15 mm Teflon stir bar actuated by an Ika stir plate. The pH was measured using a Fisher Scientific XL-15 pH meter that was calibrated freshly prior to the beginning of each titration. FAC was measured using the Hach spectrophotometer, which colorimetrically evaluates [OCl]. A friction loop consisting of a ½″ and a ¾″ pipe was used for drag reduction (DR) measurements. The pressure difference (denoted as ΔP) across the pipes, as well as the mass flow and the temperature were recorded or each fluid analyzed. Initially, the friction loop was calibrated with local tap water prior to the fluid testing and all tests were run at room temperature. Fluid was prepared by adding 0.25 gpt friction reducer to treated water and stirring for 2 minutes at 100 rpm using an overhead mixer. After the prepared fluid was added to the friction loop hopper, the differential pressure gauges were purged and the pump was primed prior to recording the data for the test. The test fluid was pumped for about 10 seconds at incremental intervals of about 6 Kg/min and the percent drag reduction (% DR) is calculated using the following equation (Eq 3): [0000] %   DR = Δ   Pwater - Δ   Pfluid Δ   Pwater · 100. ( 3 ) [0065] Each fluid had its friction pressure measured at time 0, at time=15 minutes, and at time=30 minutes to gauge the effect of the formation cleaning fluid and buffer on the acrylamide friction reducer. A control experiment without buffer and concentrated industrial sodium hypochlorite was run in a similar manner to evaluate the decrease in friction pressure inherent in running the fluid through the loop repeatedly. [0066] The first round of titrations were performed using various concentrations of concentrated industrial sodium hypochlorite in Sugar Land tap water to ensure the performance of sodium diacetate buffer was as expected in the presence of sodium hypochlorite. Several concentrations of sodium hypochlorite and other readily available reagents were tested. The results are summarized in FIG. 14 . FIG. 14 shows titration curves for addition of sodium diacetate buffer to various solutions of concentrated industrial sodium hypochlorite in tap water. [0067] In the simplest of these experiments, tap water with an initial pH of 7.82 has its pH changed to 5.43 by the addition of 0.5 gpt buffer. Addition of a further 0.5 gpt or even another 10 gpt preserve apH.of just under 5.4. There is a stir-rate dependence in the experiment—at low shear, the pH reported by the probe is not quickly representative of the bulk solution because the probe is immersed in ˜2.5″ of a 100 ml solution. With increased stirring, this feature went away. The same “high shear” stir rate was used in all the other experiments. Several water samples containing a level of concentrated industrial sodium hypochlorite appropriate to water cleaning were tested in the same manner, and all converge on pH of between 5.4 and 7 with minimal addition of buffer. Note that all the titrations trend out to final pH values between 5 and 7, even when as much as 12.5 gpt buffer is added. [0068] FIG. 15 shows titrations of some produced water samples treated with concentrated industrial sodium hypochlorite (0.21 gpt) and one sample of tap water that was pre-acidified using citric acid prior to treatment with concentrated industrial sodium hypochlorite. FIG. 15 illustrates titration of various acidic and produced waters with sodium diacetate buffer. Even acidic produced waters can have pH correction up into a more benign range using sodium diacetate buffer. [0069] The objective of friction pressure measurements was to verify which combinations of friction reducer, formation cleaning agent (concentrated industrial sodium hypochlorite), and buffer have little or no effect on the friction reducing capacity. In order to establish this, a control experiment was performed to quantify the effect of recirculation in the loop on the acrylamide polymer in the friction reducer. FIG. 16 shows drag reduction in a 0.5″ pipe using 0.25 gpt friction reducer, versus water. [0070] At high rate, the friction reducer reduces friction by about 65%. Test duration is about 3 minutes. The test was repeated after the fluid was simply left to sit in the loop under static conditions, giving the lower (30 min) trace, which shows ˜61% friction reduction. [0071] This experiment was then performed using a fresh sample with 0.25 gpt friction reducer, 0.21 gpt concentrated industrial sodium hypochlorite, and 0.5 gpt sodium diacetate. The friction reduction curves at 0, 15, and 30 minutes are shown in FIG. 17 . It is notable that 30 minutes and two cycles of testing cause roughly the same depletion of friction reducing power when sodium diacetate and sodium hypochlorite are present as was observed for the friction reducer itself. One interpretation is that chemical activity of the sodium diacetate and sodium hypochlorite on the friction reducer is negligible as compared to the shear imposed by the test. When extrapolating from a lab scale to a field situation, the shear rates may be considerably higher but the chemistry should be the same. [0072] From this data, it may be concluded that sodium diacetate buffer can correct the pH of a hypochlorite solution in produced water from a high pH to below 5.5. Sodium diacetate buffer can correct the pH of a more strongly acidic hypochlorous acid solution in produced water from a pH near 3.0 to a pH of almost 5.0. Sodium diacetate buffer does not have an adverse effect on the stability of concentrated sodium diacetate solutions at concentrations relevant to slickwater fracturing. In fact, sodium diacetate buffer adjusts pH of alkaline fluids into a range where the active water cleaning chemical in concentrated industrial sodium hypochlorite is more stable than it would be if the fluid were nearer to neutral pH. Sodium diacetate buffer and concentrated sodium hypochlorite together do not have a measurable effect on the friction reducing ability of friction reducer as measured in a friction loop test. [0073] The particular embodiments disclosed above are illustrative only, as the invention may be modified and practiced in different but equivalent manners apparent to those skilled in the art having the benefit of the teachings herein. Furthermore, no limitations are intended to the details herein shown, other than as described in the claims below. It is therefore evident that the particular embodiments disclosed above may be altered or modified and all such variations are considered within the scope and spirit of the invention. Accordingly, the protection sought herein is as set forth in the claims below.
Methods and apparatus of embodiments of the invention relate to a system for treating a subterranean formation including mixing equipment to form a fluid comprising sodium hypochlorite and sodium diacetate; and pumps and a tubular to introduce the fluid into the subterranean formation, wherein a surface of the subterranean formation contains at least 15 percent less microorganisms than if no sodium hypochlorite were in the fluid. Methods and apparatus of embodiments of the invention relate to a method of producing a petroleum product from a wellbore including using a well treatment system comprising mixing equipment, pumps, and a tubular, forming a fluid comprising sodium hypochlorite and sodium diacetate; and introducing the fluid to the well treatment system to achieve a reduced population of microorganisms in the system. Methods and apparatus of embodiments of the invention relate to a system, comprising: a subterranean formation, a well treatment apparatus comprising mixing equipment, pumps, and a tubular, and a fluid comprising sodium hypochlorite and sodium diacetate to achieve a reduced population of microorganisms in the system. Methods and apparatus of embodiments of the invention relate to a method for treating a subterranean formation, comprising forming a fluid comprising sodium hypochlorite, a buffer, and a polymer; introducing the fluid to a surface of a subterranean formation; and decreasing a population of microorganisms, wherein the surface of the subterranean formation contains at least 15 percent less microorganisms than if no sodium hypochlorite were in the fluid, and wherein the fluid exhibits a pH of about 4.0 to about 7.5. Methods and apparatus of embodiments of the invention relate to a method for treating a subterranean formation, comprising forming a fluid comprising sodium hypochlorite and sodium diacetate; and introducing the fluid to a subterranean formation, wherein forming the fluid does not include introducing an acid, and wherein forming the fluid does not include forming a precipitate.
4
FIELD OF THE INVENTION The present invention relates to a color photographic light-sensitive material, more specifically a silver halide color photographic light-sensitive material which offers excellent hue reproduction. BACKGROUND OF THE INVENTION In recent years, there have been noticeable image quality improvements in silver halide multiple-layered color photographic light-sensitive materials. Specifically, with the recent progress of color photographic light-sensitive materials, major factors of image quality, particularly sharpness and graininess have reached a fair level; color prints and slide photographs of the service print size obtained by users are not said to be significantly unsatisfactory. However, with respect to color reproducibility, one of the four factors of image quality, there have been improvements in color purity and brilliant and slightly accentuated reproduction is now possible, but much remains unsatisfactory as to hue reproduction, especially for the hues which have been difficult to exactly reproduce by photography. For example, so-called red-reflecting colors, which reflect light rays longer than 600 nm in wavelength, i.e., purple colors such as purple and blue-purple and green colors such as blue-green and yellow-green are sometimes reproduced into colors by far different from the original color, which may disappoint the user. The major factors associated with color reproduction include the spectral sensitivity distribution and interimage effect (hereinafter abbreviated IIE) of color light-sensitive material. Improvement in color reproduction by IIE is disclosed in Japanese Patent Publication Open to Public Inspection (hereinafter referred to as Japanese Patent O.P.I. Publication) No. 2537/1975 and other publications. Specifically, it is known that a compound which couples with the oxidation product of color developing agent to form a development inhibitor or precursor thereof (DIR compound) has a color reproduction improving effect on silver halide multiple-layered color photographic light-sensitive materials due to IIE by retarding the development of other coloring layers by the development inhibitor released therefrom. In the case of color negative films, it is possible to prevent color staining due to secondary absorption by the coupler by using a colored coupler in such amounts that the undesirable absorption (secondary absorption) is compensated. It is also possible to obtain an IIE-like effect by using the colored coupler in amounts higher than the minimum secondary absorption compensating level. However, when using a colored coupler in excess, the increase in minimum film density makes right judgment of printing color/density correction very difficult and lengthens printing time and thus degrades workability in laboratories. These techniques have contributed to improvements in color reproduction, especially color purity. Having an inhibiting group or precursor with high mobility, diffusible DIR, which has recently been commonly used, causes hue change, though color purity can be improved, if its orientation is not well controlled. With respect to spectral sensitivity distribution, Japanese Patent Examined Publication No. 6207/1974 discloses a method in which a filter layer etc. are used to shift the spectral sensitivity distributions in the blue-sensitive and red-sensitive silver halide emulsion layers (hereinafter referred to as blue-sensitive layer and red-sensitive layer for short) toward the spectral sensitivity distribution of the green-sensitive layer to mitigate the fluctuation in color reproduction among different light sources for picture taking. However, this does not serve as a means of improving hue reproduction for the colors difficult to reproduce. Moreover, it causes significant sensitivity reduction and narrows the color reproduction range due to the wide overlap of spectral sensitivity distribution among the color sensitive layers, which hampers satisfactory reproduction of highly chromatic colors, though reproducibility is little affected by color temperature change. Generally, in controlling spectral sensitivity distribution, short wave shift of red-sensitive layer is important from the viewpoint of approximation of the peak wavelength of light-sensitive material to the human optic sensitivity for exact hue reproduction. Short wave shift of red-sensitive layer is particularly important in the reproduction of so-called red-reflecting colors such as reproduction of blue-purple color in the reproduction of flower colors. However, such short wave shift of red-sensitive layer results in chromaticity reduction, causing disadvantages in the reproducibility for skin color, which is important in the color reproduction in color photography, i.e., the healthy reddishness unique to skin color is lost and the color reproduced lacks liveliness. Japanese Patent O.P.I. Publication Nos. 20926/1978 and 131937/1984 disclose arts of short wave shift, in which the spectral sensitivity distribution in the red-sensitive layer is shifted toward that in the green-sensitive layer, but neither offers a satisfactory effect. Japanese Patent O.P.I. Publication No. 181144/1990 specifies the sensitivity difference between the blue-sensitive layer and the green-sensitive layer and the yellow filter layer density at 480 nm to improve the reproduction of blue-green and other colors. Also, an art in which spectral sensitivity and IIE are specified is disclosed in Japanese Patent O.P.I. Publication No. 160449/1987, in which IIE orientation is specified for each light-sensitive layer. Japanese Patent O.P.I. Publication No. 160448/1987 discloses an art in which a negative spectral sensitivity corresponding to the human eye spectral sensitivity is obtained by providing a cyan-containing light-sensitive layer and applying IIE on the red-sensitive layer. Specifically, in addition to the essential blue-, green- and red-sensitive layers, an IIE expression layer (cyan containing light-sensitive layer) is required to obtain the desired IIE effect, which increases the amount of silver coated raises production cost, and the obtained effect is unsatisfactory. None of the arts described above offers satisfactory color reproduction; there have been demands for light-sensitive materials offering good color reproduction. SUMMARY OF THE INVENTION The object of the present invention is to provide a silver halide color photographic light-sensitive material capable of exactly reproducing the hues which have been difficult to reproduce, particularly the hues of red to magenta colors and the hues of green colors such as blue-green and green without being accompanied by degradation of the reproducibility for the primary colors. The present inventors made investigations and accomplished the object of the present invention described above by means of a silver halide color photographic light-sensitive material having at least one blue-sensitive silver halide emulsion layer, at least one green-sensitive silver halide emulsion layer and at least one red-sensitive silver halide emulsion layer on the support, wherein the maximum sensitivity wavelength λ B of the spectral sensitivity distribution in said blue-sensitive silver halide emulsion layer falls in the range of 400 nm≦λ B ≦470 nm, the sensitivity of said blue-sensitive silver halide emulsion layer at 480 nm does not exceed 40% of the sensitivity at the maximum sensitivity wavelength λ B and the gradient of said blue-sensitive silver halide emulsion layer after blue light separation exposure γSB and the gradient of the blue-sensitive silver halide emulsion layer after white light exposure γ WB bears the relationship of γ SB /γ WB ≧1.25. The present invention is hereinafter described in detail. DETAILED DESCRIPTION OF THE INVENTION In the present invention, spectral sensitivity distribution is defined as a function of wavelength wherein the light-sensitive material is exposed to spectral light between 380 nm and 700 nm at intervals of several nanometers and its sensitivity is expressed as the reciprocal of the amount of exposure which provides a density of minimum density +1.0 at each wavelength. In the present invention, the spectral sensitivity distribution in the blue-sensitive layer should fall in the range of 400 nm≦maximum sensitivity wavelength λ B ≦470 nm, preferably 405≦λ B ≦465 nm, and more preferably 410 nm≦λ B ≦460 nm. Also, the sensitivity of the blue-sensitive layer at λ=480 nm should be not more than 40%, preferably not more than 30%, and more preferably not more than 20% of its maximum sensitivity. Although there is no limitation on the spectral sensitivity of the green- or red-sensitive layer, the maximum sensitivity wavelength is preferably 520 nm≦λ G 570 nm and 590 nm≦λ R ≦640 nm, more preferably 530 nm≦λ G ≦555 nm and 600 nm≦λ R ≦630 nm. In the present invention, to obtain the above-mentioned constitution of the spectral sensitivity distribution in the blue-sensitive layer, any appropriate means can be used. Examples of usable means include the method in which a given silver halide is spectrally sensitized with a sensitizing dye having an absorption spectrum in the desired wavelength band, the method in which the halogen composition or distribution of silver halide is optimized using no sensitizing dye to obtain the desired spectral sensitivity, and the method in which an appropriate light absorbent is used in the light-sensitive material to obtain the desired spectral sensitivity distribution. Examples of sensitizing dyes preferably used in the blue-sensitive layer to obtain the desired spectral sensitivity distribution in the light-sensitive material of the present invention are given below. ##STR1## In the present invention, any known light-sensitive silver halide can be used in each light-sensitive layer. Although the light-sensitive silver halide is preferably composed of silver iodobromide, which is commonly used in picture taking materials, silver chloroiodobromide, silver bromide, silver chloride and others can also be used. With respect to the blue-sensitive layer, it is preferable to use a silver iodobromide or silver chloroiodobromide having a silver iodide content of not more than 4 mol %, more preferably not more than 3 mol % from the viewpoint of control of the spectral sensitivity distribution in the blue-sensitive layer and easy obtainment of IIE. It is also preferable that at least the silver halide in the blue-sensitive layer contain tabular silver halide grains. The tabular silver halide emulsion for the present invention preferably has an aspect ratio (diameter/thickness) of not less than 3.0, more preferably 3.5 to 10, and still more preferably 4.0 to 8.0. The diameter of a grain mentioned here is defined as the diameter of the circle occupying the same area as the projected area of a silver halide grain as determined on an electron micrograph of the grain. The projected area of a grain can be calculated from the sum of these grain areas. In any case, the area can be obtained by electron microscopy of a silver halide crystal sample whose grains are spread over a sample table to such extent that no grains overlap each other. The thickness of a grain can be determined by obliquely observing the sample using an electron microscope and is expressed as the distance between two parallel planes constituting the tabular silver halide grain. With respect to the tabular silver halide emulsion for the present invention, the silver halide grains having an aspect ratio of not less than 3.0 preferably account for not less than 50%, more preferably not less than 60%, and ideally not less than 70% of all silver halide grains. The tabular silver halide emulsion for the present invention is preferably a monodispersed emulsion, and it is more preferable that the silver halide grains falling in the grain size range of ±20% around the average grain diameter d m account for not less than 50% by weight. Here, the average grain size d m is defined as the grain diameter di which gives a maximum value for n i ×d i 3 , wherein d i denotes the grain diameter and ni denotes the number of grains having a diameter of d i (significant up to three digits, rounded off at the last digit). The grain diameter stated here is the diameter of the diameter of a circle converted from a grain projection image with the same area. Grain size can be obtained by measuring the diameter of the grain or the area of projected circle on an electron micrograph taken at ×10000 to 50000 (the number of subject grains should be not less than 1000 randomly). A highly monodispersed emulsion preferred for the present invention has a distribution width of not more than 20%, more preferably not more than 15% as calculated using the following equation: (Grain size standard deviation/average grain size)×100=distribution width (%) Here, average grain size is measured in accordance with the measuring method described above. Average grain size is obtained as an arithmetic mean. Average grain size=Σd.sub.i n.sub.i Σn.sub.i The tabular silver halide emulsion for the present invention is preferably a silver iodobromide or silver chloroiodobromide emulsion having an average silver iodide content of less than 4.0 mol %, more preferably 0 to 3.0 mol %, and ideally 1 to 2.5 mol %. A silver halide emulsion preferably used for the present invention can be obtained by localizing silver iodide in the grains. A preferred mode is that a silver iodobromide having a lower silver iodide content is deposited on the core having a higher silver iodide content. The silver iodide content of the core is preferably 5 to 45 mol %, more preferably 10 to 40 mol %. The silver iodide contents of the shell and the core are preferably different from each other by not less than 10 mol %, more preferably not less than 20 mol %, and ideally not less than 30 to 40 mol %. In the above-mentioned mode, another silver halide phase may be present in the central portion of the core or between the core and the shell. The volume of the shell preferably accounts for 10 to 90 mol %, more preferably 50 to 80 mol % of the total volume of all grains. The core, shell and other silver halide phases may have the same composition, or may be a group of uniformly composed phases wherein the group composition changes step by step, or may be a group of phases wherein the phase composition changes continuously, or may be a combination thereof. It is another mode of the present invention that the silver iodide content changes continuously from the center to outside of the grain and the silver iodide localized in the grains does not form a substantially uniform phase. In this case, the silver iodide content preferably decreases monotonously outwardly from the point of maximum silver iodide content in the grains. The silver halide is preferably a silver iodobromide wherein the silver iodide content in the grain surface region is not more than 7 mol %, more preferably 0 to 5 mol %, and ideally 0 to 3.0 mol %. A tabular silver halide emulsion can be produced in accordance with Japanese Patent O.P.I. Publication Nos. 113926/1983, 113927/1983, 113934/1983 and 1855/1987, European Patent Nos. 219,849 and 219,850 and other publications. For obtaining a silver halide emulsion for the present invention, it is preferable to deposit a silver iodobromide phase or silver bromide phase on the monodispersed seed crystal. A monodispersed tabular silver halide emulsion can be prepared in accordance with Japanese Patent O.P.I. Publication No. 6643/1986 and other publications. Examples of the silver halide solvent used in the seed grain formation process for the present invention include (a) the organic thioethers described in U.S. Pat. Nos. 3,271,157, 3,531,289 and 3,574,628, Japanese Patent O.P.I. Publication Nos. 1019/1979 and 158917/1979, and Japanese Patent Examined Publication No. 30571/1983, (b) the thiourea derivatives described in Japanese Patent O.P.I. Publication Nos. 82408/1978, 29829/1980 and 77737/1980, (c) the AgX solvents having a thiocarbonyl group between an oxygen or sulfur atom and a nitrogen atom, described in Japanese Patent O.P.I. Publication No. 144319/1978, (d) the imidazoles described in Japanese Patent O.P.I. Publication No. 100717/1979, (e) sulfites, (f) thiocyanates, (g) ammonia, (h) the hydroxyalkyl-substituted ethylenediamines described in Japanese Patent O.P.I. Publication No. 196228/1982, (i) the substituted mercaptotetrazoles described in Japanese Patent O.P.I. Publication No. 202531/1982, (j) water-soluble bromides, and (k) the benzimidazole derivatives described in Japanese Patent O.P.I. Publication No. 54333/1983. Gradient (γ value) can be obtained by measuring a sample developed after white light exposure and color separation exposure using a Status M filter and determining the gradient in the exposure range for ΔlogE=1.0 from D min +0.3 on the characteristic curve thus obtained. Single color light separation exposure for blue, green and red colors means exposure with a light ray having spectral energy corresponding to the spectral sensitivity distribution in each light-sensitive emulsion layer. For blue light exposure, green light exposure and red light exposure, Wratten gelatin filters W-98, W-99 and W-26, respectively, can be used for colorimetry. White light exposure in the present invention is as generally mentioned by those skilled in the art, and is achieved using a light source with a color temperature of 4800 K. to 5500 K. In the present invention, the blue-sensitive layer gradient in blue light separation exposure γ SB and the blue-sensitive layer gradient in white light exposure γ WB should bear the relationship of γ SB /γ WB ≦1.25. If the ratio exceeds the upper limit of about 2.5, processing fluctuation tends to widen. The ratio is preferably 1.35≦γ SB /γ WB ≦2.10, more preferably 1.45≦γ SB /γ WB ≦2.00. Although this value is difficult to specify decisively because it is affected by various factors including silver halide grain developability, diffusion rate in the film, film thickness, inhibitability by inhibitor and coupler coupling speed, it is advantageous to regulate IIE with a DIR compound. Generally, a blue-sensitive layer separation in blue light exposure γ SB higher than that in white light exposure γ WB means a great IIE on the blue-sensitive layer. The IIE on the blue-sensitive layer is attributable to the green- and red-sensitive layers. From the viewpoint of enhancement of the effect of the present invention, it is desirable that the IIE of the green-sensitive layer on the blue-sensitive layer is intense. Specifically, it is preferable to add a diffusible DIR compound to the green-sensitive layer adjoining the blue-sensitive layer. From the viewpoint of graininess and latitude, it is preferable that the green-sensitive layer comprise a number of layers including a high-speed layer, a low-speed layer and if necessary a moderate-speed layer. It is a preferred mode of embodiment of the present invention to add a diffusible DIR compound to the maximum sensitivity layer. With respect to the green- and red-sensitive layers as well as the blue-sensitive layer, the separation γ obtained in single light exposure is desirably higher than that obtained with white light. The ratio is preferably γ SG /γ WG ≦1.15 and γ SR /γ WR ≦1.30, more preferably γ SG /γ WG ≦1.30 and γ SR /γ WR ≦1.40, respectively. In the present invention, it is preferable to add a diffusible DIR compound, which releases a development inhibitor or precursor thereof upon reaction with the oxidation product of developing agent, as stated above. Examples of diffusible DIR compounds which can be used for the present invention are given in U.S. Pat. Nos. 4,234,678, 3,227,554, 3,617,291, 3,958,993, 4,149,886, 3,933,500, 2,072,363 and 2,070,266, Japanese Patent O.P.I. Publication Nos. 56837/1982 and 13239/1976, Research Disclosure No. 21228 (December 1981) and other publications. The diffusible DIR compounds shown in Japanese Patent O.P.I. Publication No. 110452/1990, pp. 485-489, are especially preferable. The silver halide emulsion used in the color photographic light-sensitive material of the present invention may be chemically sensitized by a conventional method. The silver halide emulsion may contain an antifogging agent, stabilizer and other additives. It is advantageous to use gelatin as the binder for the emulsion (this is not to be construed as limitative). The emulsion layers and other hydrophilic colloidal layers may be hardened and may contain a plasticizer and a dispersion (latex) of water-insoluble or sparingly soluble synthetic polymer. The present invention is preferably applicable to picture taking light-sensitive materials such as color negative films and color reversal films. The emulsion layer for the color photographic light-sensitive material of the present invention incorporates a known color developing developer. It is also possible to use a colored coupler and competitive coupler having a corrective effect, and a chemical substance which releases a photographically useful fragment such as a development accelerator, bleach accelerator, developer, silver halide solvent, toning agent, hardener, fogging agent, antifogging agent, chemical sensitizer, spectral sensitizer and desensitizer upon coupling with the oxidation product of developing agent. The light-sensitive material may be provided with auxiliary layers such as filter layers, anti-halation layers and anti-irradiation layers. These layers and/or emulsion layers may contain a dye which oozes out or bleached from the light-sensitive material during the developing process. The light-sensitive material may be formulated with a formalin scavenger, brightener, matting agent, lubricant, image stabilizer, surfactant, anti-stain agent, development accelerator, development retarder and bleach accelerator. Any substance can be used as the support, such as polyethylene-laminated paper, polyethylene terephthalate films, baryta paper and cellulose triacetate. A dye image can be obtained using the color photographic light-sensitive material of the present invention by carrying out an ordinary color photographic process after exposure. EXAMPLE The present invention is hereinafter described in more detail by means of the following example. In the following example, the amount of addition to the silver halide photographic light-sensitive material is expressed in gram per m 2 , unless otherwise specified. Also, the amount of silver halide and colloidal silver is expressed as the amount of silver. For sensitizing dyes, the amount is expressed as molar ratio to mol of silver halide in the same layer. Layers having the following compositions were formed on a triacetyl cellulose film support in this order from the support side to yield a multiple-layered color photographic light-sensitive material sample No. 101. __________________________________________________________________________Sample No. 101__________________________________________________________________________Layer 1: Anti-halation layerBlack colloidal silver 0.18UV absorbent UV-1 0.23High boiling solvent Oil-1 0.20Gelatin 1.48Layer 2: InterlayerGelatin 1.00Layer 3: Low speed red-sensitive emulsion layerMonodispersed silver iodobromide emulsion A1 (average grain size 0.27μm, average 0.70silver iodide content 7 mol %, distribution width 13%)Sensitizing dye SD-1 6.0 × 10.sup.-4Sensitizing dye SD-2 5.5 × 10.sup.-4Cyan coupler C-1 0.60Colored cyan coupler CC-1 0.15DIR compound DD-1 0.04DIR compound DD-3 0.004High boiling solvent Oil-1 0.50Gelatin 1.0Layer 4: High speed red-sensitive emulsion layerMonodispersed silver iodobromide emulsion B1 (average grain size 0.38μm, average 0.88silver iodide content 7 mol %, distribution width 14%)Sensitizing dye SD-1 2.2 × 10.sup.-4Sensitizing dye SD-2 2.0 × 10.sup.-4Cyan coupler C-1 0.13Colored cyan coupler CC-1 0.01DIR compound DD-1 0.03DIR compound DD-3 0.005High boiling solvent Oil-1 0.15Gelatin 1.10Layer 5: InterlayerAnti-color staining agent SC-1 0.10High boiling solvent Oil-2 0.10Gelatin 1.00Layer 6: Low speed green-sensitive emulsion layerMonodispersed silver iodobromide emulsion A1 0.90Sensitizing dye SD-2 8.5 × 10.sup.-5Sensitizing dye SD-3 8.0 × 10.sup.-4Magenta coupler M-1 0.53Colored magenta coupler CM-2 0.09High boiling solvent Oil-2 0.70Gelatin 1.10Layer 7: High speed green-sensitive emulsion layerMonodispersed silver iodobromide emulsion B1 0.90Sensitizing dye SD-4 3.0 × 10.sup.-4Sensitizing dye SD-5 1.8 × 10.sup.-4Magenta coupler M-1 0.17Colored magenta coupler CM-1 0.08High boiling solvent Oil-2 0.40Gelatin 0.90Layer 8: Yellow filter layerYellow colloidal silver 0.11Anti-color staining agent SC-1 0.08High boiling solvent Oil-2 0.08Gelatin 1.00Layer 9: Low speed blue-sensitive emulsion layerMonodispersed silver iodobromide emulsion A1 0.45Sensitizing dye SD-6 7.0 × 10.sup.-4Yellow coupler Y-1 0.40Yellow coupler Y-2 0.30DIR compound DD-1 0.01High boiling solvent Oil-2 0.06Gelatin 0.90Layer 10: High speed blue-sensive emulsion layerMonodispersed silver iodobromide emulsion B1 0.65Sensitizing dye SD-6 4.8 × 10.sup.-4Yellow coupler Y-1 0.18High boiling solvent Oil-2 0.08Gelatin 0.50Layer 11: First protective layerFine grains of silver iodobromide emulsion 0.40(average grain size 0.08 μm)UV absorbent UV-1 0.07UV absorbent UV-2 0.10High boiling solvent Oil-1 0.07High boiling solvent Oil-3 0.07Gelatin 0.65Layer 12: Second protective layerAlkali-soluble matting agent (average grain size 2 μm) 0.15Polymethyl methacrylate (average grain size 2.2 μm) 0.04Lubricant WAX-1 0.04Gelatin 0.60C-1 ##STR2##M-1 ##STR3##Y-1 ##STR4##Y-2 ##STR5##CC-1 ##STR6##CM-1 ##STR7##CM-2 ##STR8##DD-1 ##STR9##DD-2 ##STR10##DD-3 ##STR11##DD-4 ##STR12##Oil-1 ##STR13##Oil-2 ##STR14##Oil-3 ##STR15##SC-1 ##STR16##UV-1 ##STR17##UV-2 ##STR18##WAX-1 ##STR19##Weight average molecular weight Mw = 3,000SD-1 ##STR20##SD-2 ##STR21##SD-3 ##STR22##SD-4 ##STR23##SD-5 ##STR24##SD-6 ##STR25##__________________________________________________________________________ In addition to these compositions, a coating aid Su-1, a dispersing agent Su-2, a viscosity regulator, hardeners H-1 and H-2, a stabilizer ST-1, an antifogging agent AF-1 and two kinds of AF-2 having a weight average molecular weight of 100,000 or 1,100,000, respectively, were added. ##STR26## Sample Nos. 102 through 107 were prepared in the same manner as with Sample No. 101 except that the emulsions and sensitizing dyes in the blue-sensitive layers (Layers 9 and 10) and the DIR compounds in the green-sensitive layers (Layers 6 and 7) were changed as shown in Table 1. TABLE 1__________________________________________________________________________Sample No. 101 102 103 104 105 106 107__________________________________________________________________________Blue-Layer 10 Emulsion B1 B2 B1 B2 B3 B3 B3sensitive Sensitizing dye SD-6 SD-6 SS-13 SS-13 SS-13* SS-13* SS-13*layerLayer 9 Emulsion A1 A2 A1 A2 A3 A3 A3 Sensitizing dye SD-6 SD-6 SS-13 SS-13 SS-13* SS-13* SS-13*Green-Layer 7 DIR compound -- DD-2 DD-2 DD-2 DD-2 DD-4sensitive (amount of addition) 0.02 0.02 0.02 0.04 0.04layerLayer 6 DIR compund -- DD-2 DD-2 DD-2 DD-2 DD-4 (amount of addition) 0.005 0.005 0.005 0.005 0.005__________________________________________________________________________ Emulsion A2: A monodispersed silver iodobromide emulsion (average grain size 0.27 μm, average silver iodide content 3.5 mol %, distribution width 12%). Emulsion A3: A tabular silver iodobromide emulsion (average grain size 0.52 μm, aspect ratio 6.6, average silver iodide content 2.0 mol %). Emulsion B2: A monodispersed silver iodobromide emulsion (average grain size 0.38 μm, average silver iodide content 3.5 mol %, distribution width 15%). Emulsion B3: A tabular silver iodobromide emulsion (average grain size 0.88 μm, aspect ratio 5.5, average silver iodide content 2.0 mol %). Using these sample Nos. 101 through 107, a JIS standard color slip (glossy type) produced by Nippon Kitei Kyokai and a cloth chart including five kinds of red cloth ranging from red to purple as determined on the hue ring were photographed, followed by the following color developing process. After single color exposure through a 380-700 nm interference filter, each sample was developed and spectral sensitivity distribution was determined. B, G and R separation exposure was conducted using a Wratten filter and the value for γ SB /γ SW was calculated from D min +0.1 in the exposure range of ΔlogE=1.0. ______________________________________Processing procedures (38° C.)______________________________________Color development 3 minutes 10 secondsBleaching 6 minutes 30 secondsWashing 3 minutes 15 secondsFixation 6 minutes 30 secondsWashing 3 minutes 15 secondsStabilization 1 minute 30 secondsDrying______________________________________ The processing solutions used in the respective processing procedures had the following compositions: ______________________________________Color developer______________________________________4-amino-3-methyl-N-ethyl-N-(β-hydroxyethyl) 4.75 ganiline sulfateAnhydrous sodium sulfite 4.25 gHydroxylamine 1/2 sulfate 2.0 gAnhydrous potassium carbonate 37.5 gSodium bromide 1.3 gTrisodium nitrilotriacetate monohydrate 2.5 gPotassium hydroxide 1.0 g______________________________________ Water was added to make a total quantity of 1 l (pH=10.0). ______________________________________Bleacher______________________________________Iron (III) ammonium ethylenediaminetetraacetate 100 gDiammonium ethylenediaminetetraacetate 10.0 gAmmonium bromide 150.0 gGlacial acetic acid 10 ml______________________________________ Water was added to make a total quantity of 1 l, and aqueous ammonia was added to obtain a pH of 6.0. ______________________________________Fixer______________________________________Ammonium thiosulfate 175.0 gAnhydrous sodium sulfite 8.5 gSodium metasulfite 2.3 g______________________________________ Water was added to make a total quantity of 1 l, and acetic acid was added to obtain a pH of 6.0. ______________________________________Stabilizer______________________________________Formalin (37% aqueous solution) 1.5 mlKonidax (produced by Konica Corporation) 7.5 ml______________________________________ Water was added to make a total quantity of 1 l. From the developed films thus obtained, images were printed on color paper (Konica Color PC Paper type SR) so that gray of an optical density of 0.7 was reproduced into the same density. The reproduced colors and original colors were each subjected to colorimetry using a color analyzer (CMS-1200, produced by Murakami Shikisai Sha) on the basis of the L * a * b * color system, and the chromaticity difference at maximum chromaticity and the average hue difference on the cloth chart were calculated for 5PB, 5G and 5R on the JIS standard color slip. Chromaticity difference was determined by measuring (the distance from the crossing point to the original chromaticity point, in the length between the zeropoint) and the original chromaticity point when a line is drawn to pass the reproduced color points at an right angle with respect to the line passing on the zero point and the original chromaticity point on the a * b * plain. As the value decreases, the brilliancy of the color reproduced increases. Average hue difference on the cloth chart was calculated by plotting the original color and reproduced color on the a * b * plain and averaging the absolute values (Δθ) of the difference in the gradient θ of the line passing the zero point (Δθm). As the value for Δθm decreases, the hue difference decreases. From the spectral sensitivity distribution was determined the relative sensitivity at the peak wavelength on the spectral sensitivity distribution curve for D min +1.0 in blue light colorimetry, relative to the sensitivity at 480 nm. For sensitivity comparison, the following equation was used. (Sensitivity at 480 nm/maximum sensitivity)×100 (%) The results are summarized in Table 2. TABLE 2__________________________________________________________________________ 101 102 103 104 105 106 107Sample No. Comparative Comparative Comparative Inventive Inventive Inventive Inventive__________________________________________________________________________Blue-λmax (nm) 475 470 465 455 450 450 450sensitiveRelative 80 55 35 20 7 6 6layersensitivity(%) at 480 nmγ.sub.SB /γ.sub.WB 1.15 1.30 1.18 1.43 1.58 1.70 1.68Chromaticity difference 10.1 9.2 11.3 9.0 9.3 8.5 8.5Hue difference Δθm 13.8 10.9 12.1 7.3 6.9 5.8 5.2__________________________________________________________________________ As seen from Table 2, when blue separation γ alone was increased or the relative sensitivity at 480 nm of the blue-sensitive layer alone was decreased in Comparative Sample No. 101, it was difficult to reproduce brilliant chromaticity and exactly reproduce the original hue as in Sample Nos. 102 and 103, even when the other requirements were met. On the other hand, Sample No. 104, which meets the above-mentioned requirements, and Sample Nos. 105 through 107, both of which use a tabular emulsion according to the present invention, are capable of exactly reproduce the original hue with no influence on the brilliancy of the primary colors.
Disclosed is a silver halide color photographic light-sensitive material having at least one blue-sensitive silver halide emulsion layer, at least one green-sensitive silver halide emulsion layer and at least one red-sensitive silver halide emulsion layer on the support, wherein the maximum sensitivity wavelength λ B of the spectral sensitivity distribution in said blue-sensitive silver halide emulsion layer at 400 nm≦λ B ≦470 nm, the sensitivity of said blue-sensitive silver halide emulsion layer at 480 nm does not exceed 40% of the sensitivity at the maximum sensitivity wavelength λ B and the gradient of said blue-sensitive silver halide emulsion layer after blue light separation exposure γ SB and the gradient of said blue-sensitive silver halide emulsion layer after white light exposure γ WB bears the relationship of γ SB /γ WB ≦1.25. The silver halide color photographic light-sensitive material according to this invention is capable of exactly reproducing the hues that have been difficult to reproduce, particularly the hues of red to magenta colors and the hues of green colors such as blue-green and green without being accomplished by degradation of the reproducibility for the primary colors.
6
BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a mast assembly or derrick structure for drilling wells, such as oil or gas wells. It is particularly useful when installed on a floating drilling platform, such as a drilling vessel, but its use is not so limited, as many of its advantages are realized in land-based installations, or in mobile equipment for use on land. 2. Description of the Prior Art Marine drilling rigs are known in which a mast or derrick is pivoted to a floating platform for swinging movements between a horizontal position, in which the floating rig is readily moved between drilling locations or sites, and a vertical position in which the drilling operation is performed. One such known rig is disclosed in U.S. Pat. No. 2,475,933 issued July 12, 1949, "Marine Drilling Rig", Woolslayer et al. Such masts are very heavy and require great power to raise them from the horizontal to the upright position. If a hook assembly and traveling block guiding apparatus were to be added to the hoisting equipment, and if a vertical pipe rack and racker equipment were to be added to the mast or derrick, the weight of the assembly would become excessive, and it would, therefore, be impracticable to provide sufficient power to conveniently raise and lower the mast. SUMMARY OF THE INVENTION An object of the invention is to provide a drilling-mast assembly that has at least two stages that are horizontally disposed to provide a low profile and a low center of gravity, and that are conveniently swung to the upright positions for the drilling of a well. When this drilling mast assembly is provided on a mobile rig, seaworthiness or roadability as the case may be, is achieved, and the mobile rig may easily pass under bridges or other obstructions when the mast stages are reclined. Another object of the invention is to provide such a multi-stage mast, the separately swingable stages of which each carries a part of the heavy derrick equipment, such as the crown block, the traveling block, the hook assembly, the traveling block guide and positioner, the fingerboard rack, and the racker carriages and arms. The foregoing and other aims, objects and advantages of the invention, as will appear in or be evident from the following description of a preferred embodiment of the invention, are realized in a multi-stage, well-drilling mast comprising a platform; a first stage mast; means pivotally mounting said first stage mast on said platform for swinging movements between horizontal and upright positions; means for locking said first stage mast in upright position; a second stage mast; means pivotally mounting said second stage mast on said platform for swinging movements between an upright position adjacent to said first stage mast in its upright position and a horizontal position; and means for locking said second stage mast in upright position. BRIEF DESCRIPTION OF THE DRAWINGS In the drawings, in which like reference numerals refer to corresponding parts in the several views: FIG. 1 is an elevational view of a semi-submersible marine drilling platform upon which is mounted and shown in erect position an exemplary multi-stage drilling mast in accordance with the invention, the drilling mast also being shown in retracted position in dotted lines; FIG. 2 is an enlarged elevational view of the multi-stage drilling mast in retracted position, and rigged for the raising of the first stage; FIG. 3 is an elevational view, on the same scale as FIG. 2, of the multi-stage drilling mast with the first stage in erect position and the second stage in retracted position; FIG. 4 is a view similar to FIG. 3, but showing certain rigging installed for elevating the second stage; FIG. 5 is a view similar to FIG. 4, but with the first and second stages in erect position; FIG. 6 is a partial schematic view similar to FIG. 2 showing the first stage of the multi-stage mast in reclined condition, and showing rigging for erecting the first stage; FIG. 7 is a partial schematic view similar to FIG. 4 showing rigging for elevating the second stage; FIG. 8 is a right-hand side view of the first stage of the multi-stage mast taken along the line 8--8 of FIG. 5, but with the elevating rigging removed; FIG. 9 is a fragmentary view taken along the line 9--9 of FIG. 5, also with the elevating rigging removed; FIG. 10 is a further enlarged view of a portion of the multi-stage mast as seen in FIG. 3; and FIG. 11 is a view taken along the line 11--11 of FIG. 10. DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawings, particularly to FIG. 1, the semi-submersible drilling platform 21 shown is of a known type and is illustrated as being afloat on a body of water, the surface of which is indicated at 22. The platform has a main deck 23 upon which stand houses 24, 25 used for purposes of storage and shelter. The roof 26 of the house 24 provides a pad for the landing and take-off of a helicopter employed in transporting personnel and equipment between the platform and a land base. An elevated drilling floor 27 is erected on the main deck and carries the usual drawworks 28. The floor also serves as a base for and supports a multi-stage drilling mast 29 that embodies the present invention. The mast has a first or main stage 31 and a second or auxiliary stage 32, the mast being shown in the upright or drilling position. A cable 33 leads from the drawworks over a crown block 34, mounted on a water table 30 atop the first stage 31, and thence to a traveling block, not shown in FIG. 1, but hereinafter described with reference to certain subsequent figures. As is customary, the drilling floor is equipped with a rotary table, not shown, and other drilling equipment usual to rotary drilling rigs. Holes, not shown, are provided in the drilling floor 27 and main deck 23 for the passage of the drill string, not shown, which, during the drilling operation, hangs from the drilling rig and extends to the floor of the body of water and into the earth below, all as well known in marine drilling technology. As shown in dotted lines, the multi-stage mast is seen in its retracted and horizontal position in which the lower ends of both the first 31 and second 32 stages are supported by the drilling floor structure, with the upper end of the first stage 31 resting upon a vertical support 35 and the upper end of the second stage 32 resting upon another support 36. As shown, these supports are carried by the main deck 23. A supply of drill pipe 37 is contained in a rack 38 on the deck 23. Referring now to FIGS. 5, 8, 10 and 11, it is seen that an A-frame, designated by the general reference numeral 39, is carried by the drilling floor 27. The A-frame has a pair of horizontally spaced, upright, side frames 41, 42. The side frames 41, 42 are mirror images of each other, and a description of only the side frame 41 will suffice. The side frame 41 has a base rail 43, a front strut 44, and a rear strut 45, joined at their ends in a triangular configuration. A cross-brace 46 is secured between the front and rear struts and parallel to the base rail 43, and a gusset 47 is welded in the apex between the front and rear struts. The base rail is suitably fastened to the drilling floor 27. Between the tops of the side frames 41, 42, a horizontal arbor 48 is welded. The arbor provides a structural member for the A-frame 39, and also serves to rotatably mount the sheaves 49, 51, 52. Collars 53' are fixed to the arbor to position the sheaves in spaced relation therealong. As best seen in FIGS. 5 and 8, the first or main stage 31 of the mast is a trusswork structure having four upright members or legs at the respective four corners thereof. Two of the upright members 52, 54 are at the front of the first stage, and the other two, one 55 of which seen in FIG. 5 are at the rear. The rear upright members 55 have downward extensions 56 bent at an angle to conform to and lie adjacent to the front struts 44 of the A-frame, previously described. The downward extensions 56 are joined to the respective front legs 53, 54 at the bottom of the first stage, and the joints are provided with gussets 57, as shown in FIG. 10. Cross braces 58 and sway braces 59 add rigidity and strength to the structure. As best seen in FIGS. 8 and 10, a pair of laterally spaced, upstanding clevises 61, 62 are secured to the drilling floor 27 to receive the gussetted bottom portions 63, 64 of the first stage. These bottom portions are pivoted to the clevises by pivot pins 65, 66, about which the first stage may be swung to vertical and horizontal positions. The first stage is releasably secured in its upright position by means shown in detail in FIGS. 10 and 11. Referring to these figures, it is seen that the arbor 48 has two upstanding lugs 67, 67 welded to it, each near an end of the arbor. Cooperating lugs 68, 68 are welded to the rear legs 55. Each pair of opposed lugs 67, 68 has a locking bolt 69 passing through aligned holes in the lugs. Washers 71', 71' are placed on the bolts and between the lugs. Thus, when the bolts are tightened, solid connections are made between the pairs of opposed lugs. When the bolts are removed, the first stage of the mast is free to be lowered to horizontal position, as is described later hereinafter. Turning now to FIGS. 5, 9 and 10, it is seen that the second stage 32 is also a trusswork structure having four upright members or legs at the corners thereof. Two of these legs 71, 72 are at the front of the stage, and two 73, 73 are at the rear. Each of the front legs has a downward extension 74, 74 inclined rearwardly and joined to the respective rear legs 73 at their lower ends 75, 75. These lower ends are provided with gusset plates 76 (See FIG. 10) for strengthening the joints. A pair of laterally spaced pivot brackets 77, 77 are anchored to the drilling floor 27, and pivot pins 78, 78 are passed through aligned holes in the brackets 77, 77 and the lower ends 75, 75 of the second stage to pivotally mount the latter for movement between its erect and recumbent positions. The top of the second stage has a horizontal frame including a transverse member 79 and spaced side members 81, 81, the inner ends of the latter, as seen in FIG. 8, being received between and adjacent to the front legs 53, 54 of the first stage, and releasably locked thereto by removable locking pins 82, 82. Cross-braces 83 and sway braces 84 extend between the legs of the second stage to add strength and rigidity to it. Referring again to FIGS. 5 and 8, it is seen that the first or main stage 31 of the multi-stage mast of the invention carries the hoisting equipment. This equipment includes not only the crown block 34, previously referred to, but also a traveling block 85 suspended from the crown block by the wire-rope cable 33, mentioned hereinbefore. The traveling block is raised and lowered in the first stage by the drawworks 28 to move the drilling string (not shown) into and out of the well, as is conventional. A hook assembly 86 is suspended from the traveling block by a bail 87, and the assembly has a hood member 88 from which is suspended the load to be raised or lowered. Block and hook positioning and guiding apparatus is also provided. In the illustrated embodiment, this apparatus has a carriage 89 vertically movable on a pair of parallel, vertical guide rails 91, 91 affixed to the first stage structure. A pair of vertically spaced, parallel links 92, 92 is pivoted to the carriage and the traveling block, and a third parallel link 93 is pivoted to the carriage and the hook assembly. Motor means, not shown, in the form of a piston-and-cylinder device, one end of which is attached to the carriage and the other end of which is attached to the traveling block, moves the traveling block and hook assembly from a position on the center line of the first stage, which is an extension of the center line of the well, to another position displaced to the rear of the center line, and selectively holds the traveling block and hook assembly in either of such positions. With this apparatus, drill pipe may be handled rapidly in making round trips for the purpose of replacing a worn drill bit, for example. This hoisting apparatus and its method of use are well known, per se, and are more fully disclosed in U.S. Pat. No. 3,507,405 issued Apr. 21, 1970, "Block and Hook Structure Positioning and Guiding Apparatus", Taylor L. Jones et al., to which reference is made. Reverting now to FIGS. 5 and 9, it is seen that the second or auxiliary stage 32 of the mast of the invention carries the pipe storage racks and the equipment for racking and unracking the stands of drill pipe and the drill collars, and for transporting them to racked positions and positions over the rotary table and in line with the well bore. The pipe storage and racker apparatus may be of the kind shown and described in U.S. Pat. No. 3,501,017 issued Mar. 17, 1970, "Finger Board and Racker Apparatus and Method", Noal E. Johnson et al, and in U.S. Pat. No. 3,561,811 issued Feb. 9, 1971, "Well Pipe Racker", John W. Turner, Jr., to which reference is made for a more complete disclosure. In brief, the pipe storage equipment or rack includes a fingerboard 94 mounted on the second stage near the upper end thereof, an intermediate rack member 95, and a base 96 on the floor 27. Stands of pipe are received vertically in the rack, with their lower ends resting on the base 96, their upper ends received in slots (not shown) in the fingerboard 94, and their medial portions embraced in the intermediate rack member 95. Further, and also in brief, the racker apparatus includes an upper racker 97, an intermediate racker 98, and a lower racker 99. The upper and lower rackers are identical in construction and operation, and the upper racker only will be described. The upper racker has a laterally extending, elongate frame 101 mounted on the front legs 71, 72 of the second stage 32. This frame provides upper and lower parallel guide rails 102, 103 on which a racker arm carriage 104 is mounted for transverse movement along the guide rails. The carriage is provided with a remotely controlled motor (not shown) for translating the carriage along the rails. A racker arm 105 is reciprocably carried in a tubular guide 106 on the carriage and mounted in the guide for forward and backward motion into and out of the first stage 31. The arm is moved in its tubular guide by another remotely controlled motor (not shown). At the inner end of the racker arm is mounted a racker head 107 which, as disclosed in the aforementioned U.S. Pat. No. 3,561,811 may be in the form of a claw for holding the upper end of a well pipe and moving it horizontally from place to place in the first stage 31 by effecting lateral movements of the carriage 104 and inward and outward movements of the racker arm 105. The intermediate racker 98 is similar to the upper and lower rackers in the arrangement of the guide rails, the carriage with its tubular racker arm guide, and the reciprocable racker arm. However, the inner end of the racker arm 105' is provided with a vertically disposed head support and guide member 108 on which is mounted, for vertical movement, an intermediate racker head 109. This racker head is connected by a line 111 that passes over a sheave 112 to a hydraulic piston-and-cylinder motor 113, which is remotely controlled to raise and lower the intermediate racker head on the member 108. The intermediate racker head has a claw that grips a medial portion of a stand of well pipe and, operated in concert with the upper racker, transports the pipe to positions on the center line of the main stage and positions in the rack. The well pipe may be vertically manipulated by vertically moving the intermediate racker head 109. Reference is now made to FIGS. 2, 3 and 6 for showing of equipment for pivoting the first stage 31 between horizontal and vertical positions. The drawworks 28 is provided with the usual powered cable drum 114 for the hoist cable 33 that longitudinally moves the traveling block 85 and the attached hook assembly 86 in the first stage. Each of the rear legs 55, 55 of the first stage has a wire rope anchor 115, 116, and each of the downward extensions 56, 56 is provided with an inwardly projecting sheave 117, 118. A single sheave auxiliary block 119 is attached by a bail 120 to the hook 86. As best seen in FIG. 6, a length of wire rope 121, forming a sling, has one end secured to the anchor 115. The rope passes around the sheave 49 on the A-frame 39, under the sheave 117, through the auxiliary block 119, under the sheave 118, around the sheave 52, and back to the anchor 116, to which it is secured. As seen in FIGS. 2 and 6, the hook assembly 85 is positioned near the bottom of the first stage when the sling is applied. To raise the first stage to the upright position shown in FIG. 3, the drawworks is operated to reel in the hoist cable 33 and to raise the traveling block, the hook 86, and the auxiliary block 119 in the first stage. As the auxiliary block 119 is raised, the wire rope 121 sling applies a counterclockwise turning movement to the first stage 31 about the axis of the pivot pins 65 and 66 (See FIG. 8) to swing the first stage from its horizontal disposition of FIG. 2 to its vertical disposition of FIG. 3. When the first stage has reached the upright position, it is locked in that position by the locking bolts 69, 69 (See FIG. 10) as previously described. After the first stage has been locked in upright position, the wire rope 121 sling may be removed. From the foregoing description of the raising of the first stage, it will be obvious that the first stage may be lowered to its horizontal position by reversing the operations performed in raising it. In lowering the first stage, it may be necessary, in the initial increments of movement, to jack it in the counterclockwise direction until its center of gravity passes over its pivot axis, whereupon gravity will urge it towards its horizontal position to which it is gently lowered by braking the drawworks drum 114. The raising and lowering of the second stage 32 will now be described with reference to FIGS. 4, 5 and 7. Referring particularly to FIG. 7, one sees that the rear legs 73, 73 of the second stage 32 are provided with sheaves 122, 123, and that the front legs 53, 54 of the first stage 31 have cooperating sheaves 124, 125 mounted thereon. A sling is formed of a wire rope 126, one end of which is secured to the left-hand end of the arbor 48 of the A-frame 39. The rope then passes around the sheaves 122, 124, through the auxiliary block 119, around the sheaves 125, 123, and back to the right-hand end of the arbor 48, where it is secured. In order to swing the second stage 32 from its horizontal position, as seen in FIG. 4, to its vertical position, as seen in FIG. 5, the traveling block 85 is lifted by operating the drawworks 28 to wind the cable 33 on the drum 114. The raising of the traveling block also raises the hook assembly 86 and the auxiliary block 119, which pulls the wire rope 126 sling from its position of FIG. 4 to its position of FIG. 5, thereby applying torque to the second stage and swinging it counterclockwise about the pivots 78, 78 (See FIG. 9) into the upright position. The second stage is locked in upright position to the first stage by inserting the locking pins 82 through the side members 81 of the second stage and the front legs 53, 54 of the first stage, as hereinbefore described. After the second stage has been locked upright, the wire rope 126 sling and the auxiliary block 119 may be removed to prepare the mast for drilling. To lower the second stage from vertical to horizontal position, the steps followed in raising it are merely reversed. In operation, the drilling vessel, with both stages of the multi-stage mast reclined, as shown in dotted lines in FIG. 1, is towed to the drilling site and anchored thereat. The two stages of the mast are successively raised to their upright positions and locked therein, as hereinbefore described and as shown in FIG. 1. With the mast so erected, the drilling of the well is carried out in the usual way. When round trips are made, as for the purpose of replacing a worn out bit, the drilling string is withdrawn from the well by means of the hoisting equipment carried by the main stage of the mast and is broken down, usually into stands of three singles, and racked in the fingerboard rack, carried by the auxiliary stage, by use of the rackers, also carried by the auxiliary stage. Following completion of the well and removal of the well pipe from the mast, the two stages of the mast are successively lowered to their horizontal positions, and the drilling vessel is ready to be moved to another location. From the foregoing description it is seen that the present invention provides a multi-stage, drilling mast that achieves the objects of the invention. While an exemplary form of the invention is herein shown and described, it will be understood that this form is merely illustrative, and that the scope of the invention is best defined in the accompanying claims. Various changes in the illustrated embodiment of the invention will occur to those skilled in the art without departing from the spirit and scope of the invention.
A multi-stage, well-drilling mast assembly, particularly adapted to mobile drilling platforms, such as drilling vessels, the assembly having a main stage mast and an auxiliary mast, both pivoted to the platform for swinging movements between horizontal and vertical positions. The main stage carries well pipe hoisting equipment, and the auxiliary stage carries rack equipment for vertically storing well pipe, and racker equipment for moving the well pipe between the rack and the center line of the mast assembly. Slings operated by the hoisting equipment swing the stages between horizontal and vertical positions. A low profile and a low center of gravity are achieved when the stages are horizontally disposed. The distribution of the weight of the hoist, the rack, and the rackers between the stages of the mast assembly provides a multi-stage mast assembly in which the individual stages may be conveniently swung between reclined and vertical, well-drilling positions.
4
BACKGROUND OF THE INVENTION This invention relates to a crane and method of using a crane. More specifically, but not by way of limitation, this invention relates to a swing arm crane and a method of using the crane to lift loads on a rig. In the course of searching for oil and gas, operators drill in various regions of the globe, including the world's oceans. Many times, a floating type of drilling rig or floating production platform is utilized, as is well understood by those of ordinary skill in the art. During the course of drilling, completion, and/or production operations, operators may find it necessary to perform remedial well work. Remedial well work can be performed with a coiled tubing unit, a snubbing unit, workover rig, etc. In the use of a coiled tubing unit and/or snubbing unit, operators will rig up a lift frame within the derrick. The lift frame is used to support injector heads, lubricators, etc. during the rig up, operation and rig down phases of the well work. Many times, the operator finds it necessary to lift equipment from a staging area to the work area within the lift frame. Prior art equipment, such as cranes, have been used to aid operators in picking up and moving supplemental equipment from one point to another. However, oil field equipment is bulky. Prior art cranes and/or winches needed to lift this equipment are inadequate. In fact, operators will many times use a drilling rig's air tugger in order to lift and move equipment. However, air tuggers are generally ill suited and/or positioned for lifting this type of equipment. For instance, the air tuggers have a limited swing range of motion and have other uses for the rig crew. Therefore, there is a need for a crane that will lift equipment. There is also a need for a crane that has a significant swing range of motion. There is also a need for a crane that can be used in conjunction with remedial well work on drilling and production platforms. The present invention will meet these needs, as well as others, as will be more readily understood by a reading of the following. SUMMARY OF THE INVENTION An apparatus for lifting and moving a load is disclosed. The apparatus comprises a lift frame having a first and second vertical member, and wherein the first and second vertical member are connected so that an inner portion is provided defining a working window area. The apparatus further comprises a rotary actuator mounted on the first vertical member, and an arm having a first end and a second end, and wherein the first end of the arm is pivotly connected to the rotary actuator. The rotary actuator may be a hydraulic motor. The arm is pivotal from an area exterior of the working window area to an area within the working window area. The apparatus also includes a cable attached at a distal end to the first end of the arm and a proximal end to the load. The apparatus may further comprise a bracket mounted on the first vertical member, with the bracket having a hinge operatively attached thereto. In the preferred embodiment, the second end of the arm is attached to the hinge so that the arm is pivotal from an area exterior of the working window area to an area within the working area. The apparatus may further comprise a winch means, operatively attached to the arm, for lifting a load with the cable. In one of the preferred embodiments, the winch means comprises a winch attached to the second end of the arm, and wherein the cable is partially spooled on the winch, with the cable being directed through a sheave attached to the first end of the arm, and wherein the sheave is pivotal from the area exterior of the working window area to the area within the working window area. The lift frame may further comprise a coiled tubing injector head attached to the lift frame, and an elevation means for adjusting the orientation of the coiled tubing injector head. The elevation means comprises a means for moving the injector head in a horizontal plane and means for moving the injector head in a vertical plane. The apparatus may further comprise a connector plate connected to the first and second vertical member and a lift sub operatively associated with a block contained within a derrick of a rig. In one preferred embodiment, the coiled tubing injector head is connected to a well head, and wherein the well head is connected to a well that extends to a subterranean zone. A method for performing well work on a rig is also disclosed, wherein a well extends from the rig to a subterranean zone. The method comprises providing a well intervention string assembly on the rig. The well intervention string assembly includes a lift frame, with the lift frame comprising: a first and second vertical member, and wherein the first and second vertical member are connected so that an inner portion is provided defining a working window area; a rotary actuator mounted on the first vertical member; an arm attached to the first vertical member and wherein the arm is pivotal from an area exterior of the working window area to an area within the working window area; and a cable, operatively attached to the arm, for lifting a load. The method further comprises rigging up a coiled tubing injector head to the lift frame. The method also comprises lifting a piece of supplemental equipment with the cable from the area exterior of the working window area. Thereafter, the arm is rotated with the rotary actuator so that the piece of supplemental equipment is rotated to within the working window area and the equipment is rigged up to the well intervention string assembly. A coiled tubing is lowered through the injector head into the well. In one of the preferred embodiments, a second end of the arm is attached to a hinge and the hinge is attached to the first vertical member so that the arm is pivotal from an area out of the working window area to an area within the working area. Also in one preferred embodiment, a connector plate is connected to the first and second vertical member and a lift sub is operatively attached with the block contained within the derrick of the rig, and wherein the lift sub is connected to the connector bar. In this embodiment, the step of rigging up the coiled tubing injector head includes suspending the lift frame from the derrick of the rig with the lift sub. An advantage of the present invention is that an angle of rotation of 180 degrees is possible. Another advantage is that an operator may perform work within a work window and the swing arm crane can be pivoted outside the work window. Still yet another advantage is that the use of the device herein disclosed frees up other crane devices on a rig such as the air tuggers. Yet another advantage is that an operator may use power means that are already present on the rig, such as a hydraulic power source or a pneumatic power source. A feature of the present invention includes use of a rotary actuator, such as a hydraulic motor, to pivot the arm. Another feature is that the arm freely rotates in an angle of rotation of at least 180 degrees. Still yet another feature is that the arm mounts to a support structure, such as a lift frame and the arm can rotate from an aft position to a fore position relative to the support structure. Yet another feature is that the winch, in one preferred embodiment, is attached to the bottom end of the arm, and the sheave is at the top end of the arm, thereby providing for a balanced mechanical design when lifting or lowering loads. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an isometric view of the swing arm crane attached to a support structure. FIG. 2 is front plan elevation view of the swing arm crane mounted on a lift frame, with the swing arm crane positioned within the working area. FIG. 3 is a side plan elevation view of the lift frame of FIG. 2 , wherein the swing arm crane has been pivoted 90 degrees. FIG. 4 is a front plan elevation view of the swing arm crane with the swing arm crane mounted on the lift frame, with the swing arm crane being pivoted exterior of the working area. FIG. 5 is a top plan view of the swing arm crane seen in FIG. 4 illustrating the range of motion. FIG. 6 is an isometric view of the swing arm crane attached to a coiled tubing lift frame positioned on a rig. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to FIG. 1 , an isometric view of the swing arm crane 2 will now be described. The swing arm crane 2 is attached to a support structure 4 . A base plate 6 is attached to the support structure 4 via nuts and bolts. Other attachment means are possible, such as attaching the base plate 6 via welding. The base plate 6 has a first hinge means 8 attached thereto, and wherein the first hinge means 8 has a first end 10 attached to the base plate 6 and a second end 12 connected to the attachment plate 14 . The first hinge means 8 will contain the rotary actuator means 16 for pivoting the swing arm 18 , and wherein the arm 18 is pivotal from an area exterior of a working window area to an area within the working window area, as will be explained in greater detail later in the application. The rotary actuator means 16 is a hydraulic motor in one preferred embodiment, and wherein the motor is commercially available from Helac Corporation under the name Rotary Actuator (model no. L30-65E FT 180 52 OG). Hydraulic input line Li and output line Lo are shown. It should be noted that it is also possible to have a rotary actuator means 16 that is powered via a pneumatic power source. Extending from the attachment plate 14 is the member 20 , and wherein the member 20 has connected thereto a first cable sheave 22 and a second cable sheave 24 . An angle brace 25 for supporting the second cable sheave 24 is also provided. At the bottom end of the arm 18 is the winch 26 , and wherein the winch 26 will, in one preferred embodiment, be a two-ton winch with a 7/16 inch braided cable 28 . In the most preferred embodiment, the winch 26 is a hydraulic winch, with FIG. 1 showing the input line Li and output line Lo. The cable 28 is directed from the winch 26 , through the first cable sheave 22 , then through the second cable sheave 24 . As can be seen in FIG. 1 , an attachment means 29 for attaching to supplemental equipment is provided on the distal end of the cable 28 , and wherein in one preferred embodiment, the attachment means 29 is a hook 29 . The proximal end of the cable 28 is attached to the winch 26 . The winch 26 is pivotly attached to a second hinge means 30 and wherein the second hinge means 30 is connected to a bracket 31 . As seen in FIG. 1 , in the most preferred embodiment, the bracket 31 is attached to the support structure 4 via conventional means such as nuts and bolts. As noted earlier, other means are possible such as welding. Note that in FIG. 1 , the swing arm crane 2 is in a balanced state in that the cable 28 , that leads from an aft attached winch 26 , extends to the first cable sheave 22 which in turn extends perpendicularly to the second sheave 24 and wherein the cable 28 then extends perpendicularly therefrom, and wherein the cable 28 will then be attached to a load. In this configuration, when a load is lifted, the moment created at base plate 6 will tend to want to rotate the bottom end of the arm 18 outward; however, since the arm 18 is attached to the support structure 4 via the second hinge means 30 , the force will be countered by the support structure 4 , and the swing arm crane 2 is in a stable state. Additionally, the swing arm crane 2 remains in this stable state through the 180 degree range of motion i.e. from a position fore and aft of the support structure 4 . Referring now to FIG. 2 , a front plan elevation view of the swing arm crane 2 mounted on a lift frame 32 is illustrated. The lift frame 32 is commercially available from Devin International Inc. under the name Coiled Tubing Lift Frame. The swing arm crane 2 is shown within a working area window, with the working area window being designated by the numeral 34 . It should be noted that like numbers appearing in the various figures refer to like components. In one of the preferred embodiments, the lift frame 32 comprises generally a first vertical member 36 and a second vertical member 38 . The vertical members are connected via a top connector plate 40 and a bottom connector plate 42 , and wherein the connector plates 40 , 42 structurally connect the vertical members 36 , 38 . Also included in the lift frame 32 is the winch mounting plate 44 , and wherein the winch mounting plate 44 is connected at both ends to the vertical members 36 , 38 as shown in FIG. 2 . The winch mounting plate 44 also has the second winch means 46 for winching equipment and other loads as desired by the operator. For instance, the second winch means 46 can be used to lift and lower the coil tubing injector head (which can be seen in FIG. 6 ). Returning to FIG. 2 , the cable 48 is shown partially spooled on the second winch means 46 and can be used to aid in rigging up the coiled tubing injector head. As shown in FIG. 6 , the lift frame 32 can also have an elevation device 50 for the coiled tubing injector head operatively attached to the lift frame 32 . As illustrated in FIG. 6 , the elevation device 50 is operatively included, and wherein the elevation device 50 is commercially available from Devin International Inc. under the name Mini-Track. The elevation device 50 can lift in a vertical plane and can also move in horizontal plane in order to move the injector head for various operational purposes, as will be understood by those of ordinary skill in the art. Returning to FIG. 2 , FIG. 2 also depicts a lift sub 52 . The lift sub 52 allows attachment to elevators (not shown), wherein the elevators will be suspended in the derrick of the rig via the block, as will be explained in more detail later in the application. FIG. 3 is a side plan elevation view of the lift frame of FIG. 2 wherein the swing arm crane 2 has been pivoted 90 degrees from the position illustrated in FIG. 2 . Hence, the second vertical member 38 is shown. The swing arm crane 2 is on the outer periphery of the working window area 34 . In FIG. 4 , a front plan elevation view of the swing arm crane 2 mounted on the lift frame 32 is shown, and in FIG. 4 , the swing arm crane 2 has been pivoted 180 degrees from the orientation seen in FIG. 2 . In FIG. 4 , the swing arm crane 2 is exterior of the working area window 34 . In other words, the swing arm crane 2 is no longer positioned within the working area window 34 . The swing arm crane 2 has been pivoted by the rotary actuation means 16 . As noted earlier, the rotary actuation means 16 is in one of the preferred embodiments a hydraulic motor. One of the features of the present invention is that the swing arm crane 2 can move from the area 34 to the area exterior of the working area window 34 via pivoting at the first hinge 8 and the second hinge 30 . The swing arm crane 2 can also move from the area exterior of the working area window 34 to the area inside the working area window 34 . As is understood by those of ordinary skill in the art, the coiled tubing injector head is rigged up within the working area window using the second winch means 46 . The coiled tubing injector head is rigged up to the well intervention string assembly. The well intervention string assembly (as seen in FIG. 6 ) is the surface work string connected at one end to the well and at the second end to the block. In operation, the operator may find it necessary to also rig up supplemental equipment, such as Blow Out Preventors, lubricators, down hole tools, assemblies, etc. to the well intervention string assembly. The supplemental equipment is an appendage to the well intervention string assembly. Hence, the, supplemental equipment can be picked-up with the swing arm crane 2 and wherein the supplemental equipment is outside the working area window (for instance, on the deck of the rig). The swing arm crane 2 , with the attached supplemental equipment, is rotated to within the working area window 34 , and wherein the supplemental equipment can be rigged up to the well intervention string assembly as needed. Therefore, the workers have installed certain appendage supplemental equipment with the aid of the swing arm crane 2 . FIG. 5 depicts a top plan view of the swing arm crane 2 seen in FIG. 4 . FIG. 5 illustrates the range of motion. The position denoted by the letter A shows the swing arm crane 2 oriented within the working area window 34 . The position denoted by the letter B shows the swing arm crane 2 having been rotated 90 degrees from the A position, which is still within the working area window 34 . Once the swing arm crane 2 is rotated to approximately 91 degrees, the swing arm crane 2 is exterior of the working window area 34 . Hence, the swing arm crane 2 is within the inner portion 34 when the swing arm crane 2 is within this 90 degree (right angle) range denoted by the shaded area 80 . The C position shows the swing arm crane 2 having been rotated 180 degrees from the A position, which is also exterior of the working area window 34 . Referring now to FIG. 6 , an isometric view of the swing arm crane 2 attached to the lift frame 32 positioned within a derrick 60 of rig is shown. A coiled tubing injector head 62 is shown being positioned within the working area window 34 . The coiled tubing injector head 62 is commercially available from Hydra Rig Corporation under the name Coiled Tubing Injector Head. The second winch means 46 has a hoist 64 operatively associated therewith and wherein the hoist is operatively attached to the coiled tubing injector head 62 . The swing arm crane 2 has been moved to a position exterior of the working area window 34 . The coiled tubing injector head 62 is rigged up to the well head, seen generally at 66 . The elevation device 50 may be used to lift the coiled tubing injector head 62 for various purposes during operations. The surface work string and assembly connected at one end to the well head 66 and at the opposite end to the block 68 is collectively referred to as the well intervention string assembly 70 . The well head 66 connects to a subterranean well 72 that intersects a hydrocarbon bearing reservoir 74 . In the position seen in FIG. 6 , the operator can use the swing arm crane 2 to aid in rigging up, or rigging down, by lifting supplemental equipment E required during operations, such as rigging up or rigging down BOPs, lubricators, down hole tools, assemblies, etc., as noted earlier. Once the head 62 is rigged up, the operator can run into the well with coiled tubing 76 and perform the necessary well work, as is readily understood by those of ordinary skill in the art. After the well work, the swing arm crane 2 can be used to rig down the equipment. Changes and modifications in the specifically described embodiments can be carried out without departing from the scope of the invention which is intended to be limited only by the scope of the appended claims and any equivalents thereof.
An apparatus for lifting and moving a load. The apparatus comprises a lift frame having a first and second vertical member that are connected so that a working window area is defined. The apparatus further comprises a rotary actuator mounted on the first vertical member, and an arm having a first end and a second end, and wherein the first end of the arm is pivotly connected to the rotary actuator. The arm is pivotal from an area exterior of the working window area to an area within the working window area. The apparatus may further comprise a winch, operatively attached to the arm, for lifting a load with the cable. A method of lifting a load is also disclosed.
4
BACKGROUND OF THE INVENTION The present invention relates to a switching device to be used in a camera and, more particularly, a switching device for controlling both self-timer and normal operations. Conventionally, when a self-timer operation in a camera is to be executed by a camera, the operational mode is first changed to a self-timer standby mode by means of a self-timer switch. Thereafter, the shutter release button is depressed, and the self-timer operation is carried out. However, the use of many independent switches and modes increases the cost of the camera and makes the operation of the camera complicated. Furthermore, in conventional cameras, switching devices (such as, for example, shutter release and self-timer buttons) consist of many switching parts, springs and lead wires. The combination of these factors results in many problems, among them a high part count, an overcomplicated structure, poor assembling efficiency, and high cost. SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide an improved switching device for a camera, capable of readily executing self-timer photographing, yet making the structure simple while improving assembling efficiency. In order to meet the objects of the invention, a switching device for a camera includes a photometric switch; a release switch; a shutter release button, operatively connected to the release switch and to the photometric switch, for turning On the photometric switch when half depressed and turning ON both the release switch and the photometric switch when further depressed; and a self-timer button, operatively connected to the release switch, for turning ON only the release switch when depressed. Accordingly, the switching device of the camera is able to discriminate the desired operation of self-timer or normal operations. Preferably, the switching device further includes control means for detecting the turning ON of the release switch and the photometric switch and for executing a self-timer operation when the release switch is ON but the photometric switch is OFF. In this manner, the switching device sets and executes the self-timer operation in response to a combination of switch states when the self-timer button is depressed. In this case, the control means preferably executes a photometric operation when the release switch is OFF but the photometric switch is ON, and executes a shutter release operation when the release switch is ON and the photometric switch is ON. In this manner, the switching device sets and executes subsequent photometric and shutter release operations in response to a combination of switch states when the shutter release button is depressed. In one particular case, the switching device includes a shutter release contact arranged to be depressable by the shutter release button; a self-timer contact arranged to be depressable by the self-timer button; a photometric contact opposing the shutter release contact, provided to the photometric switch; and a first and a second electrical contact provided to the release switch, the first electrical contact opposing the self-timer contact, and the second electrical contact opposing the photometric contact. Accordingly, the appropriate switches can be activated by the closing of contacts in the correct combinations when the buttons are depressed. In this case, when the shutter release button is half depressed, the shutter release contact electrically connects to the photometric contact, and when the shutter release button is further depressed, all of the shutter release contact, the photometric contact, and the second electrical contact of the release switch electrically connect. When the self-timer button is depressed, the self-timer contact electrically connects to the first electrical contact of the release switch. The correct combinations of contact positions to electrically connect the switches are achieved with this arrangement of contacts. In this arrangement of contacts, the switching device preferably includes control means for executing a self-timer operation when the self-timer contact is electrically connected to the release switch, for executing a photometric operation when the shutter release contact is electrically connected to the photometric switch, and for executing a shutter release operation when all of the shutter release contact, the photometric contact, and the release switch electrically connect. According to a particular development, the photometric switch includes a photometric switch plate upon which the photometric contact is provided, and the release switch includes a release switch plate upon which the first and second electrical contacts are provided. The use of switch plates facilitates the arrangement of the contacts. In this case, the photometric switch plate and the release switch plate are formed from conductive and resilient plate spring material, and the photometric switch plate is formed substantially in a U-shape, surrounding the release switch plate. The combinations of contact positions can thereby be compactly achieved. A particularly favorable arrangement is implemented when the U-shape of the photometric switch plate includes an upper arm above the release switch plate and a lower arm below the release switch plate, and the photometric contact is formed on the upper arm. In another development, the self-timer contact and the shutter release contact are provided on a unitary common switch plate, and the photometric switch plate and the release switch plate are supported by a chassis of the camera, and the common switch plate, shutter release button, and self-timer button are supported by a front decorative plate fixed to the camera body. In this case, each of the contact-supporting switch plates are arranged in a compact space and can be easily assembled. In a preferred arrangement, the common switch plate is provided with a first resilient arm bearing the shutter release contact and a second resilient arm bearing the self-timer contact, and the first resilient arm and the second resilient arm bias the shutter release button and the self-timer button, respectively, toward undepressed positions. In this manner, the elements of the common swatch plate serve as electrical contacts and as resilient members to provide, a return action in the button operation. According to one preferred embodiment, a plurality of resilient tabs, for holding the release switch plate and the photometric switch plate, are provided on-the chassis displaced from one another. The resilient tabs have clearances therebetween into which the release switch plate and photometric switch plate are inserted. In this manner, the assembly of the switch plates is easily accomplished. In this case, the plurality of resilient tabs preferably includes means for locking the release switch plate and the photometric switch plate into the clearances therebetween. The release switch plate may be inserted and locked between a first and a second resilient tab of the plurality of resilient tabs, and the photometric switch plate may be inserted and locked between the second resilient tab and a third resilient tab of the plurality of resilient tabs. In this manner each of the switch plates is snapped into place, and resilient tabs can participate in holding more than one switch plate, a minimum number of resilient tabs is used to hold the switch plates. In another preferred embodiment, the self-timer contact and the shutter release contact are provided on a unitary common switch plate, and the camera chassis is provided with an electrically conductive plate for connecting the common switch plate with common DX code conductive pattern terminals of a film cartridge inserted in the camera. In this case, the camera may detect whether or not a film having a DX code conductive pattern portion defining a predetermined group of film speeds is inserted in the camera. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded view showing a mounting arrangement of an embodiment of the switching devise according to the invention; FIG. 2 is an partially exploded view showing an arrangement of switches in the embodiment of a switching device; FIG. 3 is a perspective view showing the assembled condition of the embodiment of a switching device; FIG. 4 is a front view showing the mounting of the switching device to a camera body, from the viewpoint of arrow Y in FIG. 3; FIG. 5A is a sectioned view along line X--X of FIG. 3, showing a half depressed shutter release button; FIG. 5B is a sectioned view along line X--X of FIG. 3, showing a fully depressed shutter release button; FIG. 6 is a sectioned view along line X--X of FIG. 3, showing a depressed self timer button; FIG. 7 is a block diagram schematic of the embodiment of a switching device; FIG. 8 is a timing chart explaining the operation of a normal shutter release operation when the shutter release button is depressed; and FIG. 9 is a timing chart explaining the operation of self-timer operation when the self-timer button is depressed. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiment of a switching device according to the invention is shown in perspective and exploded views from FIG. 1 through FIG. 3. FIG. 1 is an exploded view showing the arrangement of switch plates on a plastic camera body 13; FIG. 2 is a partially exploded view showing switch plates and buttons assembled to the plastic camera body 13; and FIG. 3 is a perspective view showing the assembled switching device. In FIGS. 2 and 3, the plastic camera body 13 is shown by a phantom line. As shown in FIGS. 1 and 2, a photometric switch plate 21 and a release switch plate 22 are supported by portions of the plastic camera body 13. The photometric switch plate 21 is formed from resilient and conductive plate spring material, in a substantially a U-shape. A lower arm 21D forms a lower side of the U-shape, while an upper (plate spring) arm 21U forms an upper portion of the U-shape. An upper contact 21x, which acts as a photometric switch PH SW in combination with a shutter release contact arm 19x (shown in FIGS. 2 and 4), is formed on the upper arm 21U. The photometric switch plate 21 further includes a terminal 21b extending from the lower arm 21D, to which a signal connection to a microcontroller 25 (shown in FIG. 7) is made. The release switch plate 22 is formed from resilient and conductive plate spring material, and is shaped having a mounting base 22a with a long arm 22L and a short arm 22S extending in the same direction from the base 22a. The long arm 22L is bent up from the base 22a, and has a first contact 22x near its distal end. The first contact 22x acts as a release switch RLS SW in combination with a self-timer contact arm 19y (shown in FIGS. 2 and 4). The short arm 22S is substantially coplanar with the base 22a, and has a second contact 22y near its distal end. The second contact 22y acts as the release switch RLS SW in combination with the shutter release contact arm 19x (shown in FIGS. 2 and 4) and the upper contact 21x. The release plate 22 further includes a terminal 22b extending from the base 22a, to which a signal connection to the controller 25 (shown in FIG. 7) is made. As shown in FIG. 1, a lower resilient locking tab 14, an upper resilient locking tab 15, and a middle resilient locking tab 16 extend from the camera body 3. The locking tabs 14, 15, and 16 are used for mounting the photometric switch plate 21 and release switch plate 22. From the perspective of FIG. 1, the middle locking tab 16 is separated from the upper locking tab 15 in the vertical direction by a clearance approximately the thickness of the mounting base 22a of the release switch plate 22, and is positioned to the left of the upper locking tab 15. The lower locking tab 14 is separated from the middle locking tab 16 in the vertical direction by a clearance approximately the thickness of the lower arm 21D of the photometric switch plate 21, and is positioned to the right of both the upper locking tab 15 and the middle locking tab 16. The lower locking tab 14 is provided with an upwardly extending locking hook 14a. Similarly, the middle locking tab 16 is provided with an upwardly extending locking hook 16a. One of the features of this embodiment is the supporting and mounting structure for the photometric switch plate 21 and release switch plate 22, including the locking tabs 14, 15, and 16, and shown in FIGS. 1, 2, and 4. The lower arm 21D of the photometric switch plate 21 is inserted and locked in the clearance between the lower locking tab 14 and the middle locking tab 16. Each of the locking tabs 14, 15, and 16 is resilient, being unitarily formed with the plastic camera body. According to this embodiment, the locking tabs 14, 15, and 16 of the plastic camera body 13 slightly bend (resiliently) when the switch plates 21 and 22 are mounted to the body 13, but the plate spring switch plates 21 and 22 may be alternatively formed to be more resilient than the plastic camera body 13. When the photometric switch plate 21 is inserted, it pushes the locking-hook 14a of the resilient lower locking tab downward, and also pushes the resilient middle locking tab 16 slightly upward. The lower side of a camera body portion 13a provides an additional resistance on the side of the lower locking tab 14 opposite the middle locking tab 16. Alternatively, the locking tabs 14, 15, and 16 can be formed to slightly overlap in the vertical direction to act against any moment upon insertion when the trailing edge of the lower arm 21D passes the locking hook 14a, the lower arm 21D snaps into the clearance between the tabs 14 and 16, and the tabs 14 and 16 elastically snap back to their neutral positions. At this time, a click sound is generated, verifying the proper mounting of the photometric switch plate 21. The locking hook 14a prevents any movement of the photometric switch plate 21 out of the clearance. Thus, the photometric switch plate 21 inserted in the slit is locked into the clearance between the lower locking tab 14 and the middle locking tab 16 by the locking hook 14a. The mounting base 22a of the release switch plate 22 is similarly supported and locked, and is similarly inserted. Specifically, the mounting base 22a of the release switch plate 22 is inserted and locked in the clearance between the middle locking tab 16 and the upper locking tab 15. When the release switch plate 22 is inserted, it pushes the locking hook 16a of the resilient middle locking tab 16 downward, and also pushes the resilient upper locking tab 15 slightly upward. The upper side of the camera body portion 13a provides an additional resistance on the side of the upper locking tab 15 opposite the middle locking tab 16. When the trailing edge of the mounting base 22a passes the locking hook 16a, the mounting base 22a elastically snaps into the clearance between the tabs 16 and 15, and the tabs 16 and 15 elastically snap back to their neutral positions. At this time, a click sound is generated, verifying the proper mounting of the release switch plate 22. The locking hook 16a prevents any movement of the release switch plate 22 out of the clearance. Thus, the release switch plate 22 inserted in the slit is locked into the clearance between the middle locking tab 16 and the upper locking tab 15 by the locking hook 16a. As shown in FIGS. 2 through 6, a shutter release button 17 and a self-timer button 18 are depressably supported on a front decorative plate 10 (shown by a phantom line in FIGS. 5A, 5B, and 6). A common switch plate 19 constructed from electrically conductive plate spring material is fixed to the front decorative plate 10 near the shutter release button 17 and self-timer button 18. Specifically, the common switch plate 19 is fixed to the front decorative plate 10 by means of pins 19d passing through a plurality of mounting holes 19a formed on the common switch plate 19 (as shown in FIGS. 4 through 6). The front decorative plate 10 is fixed in turn to the plastic camera body 13. A resilient shutter release contact arm 19x and a resilient self-timer contact arm 19y fork from the (plate spring) common switch plate 19 toward the lower portion of the shutter release button 17 and the self-timer button 18, respectively. The resilient contact arms 19x and 19y are upwardly biased to contact the buttons 17 and 18, respectively, so that the shutter release button 17 and the self-timer button 18 are held at their undepressed positions. The common switch plate 19 is further provided with a brush 19c to contact a common conductive plate 12. Since the photometric switch plate 22 is mounted in the camera body 13 as shown in FIG. 2, when the front decorative plate 10 is assembled to the camera body 13 to place the common switch plate in the position shown in FIG. 3, the upper contact 21x opposes the shutter release contact arm 19x of the common switch plate 19. Furthermore, since the release switch plate 22 is mounted in the camera body 3 as shown in FIG. 2, the first contact 22x on the long arm 22L opposes the self-timer contact 19y of the common switch plate 19, and the second contact 22y on the short arm opposes the bottom of the upper contact 21x of the photometric switch plate 21. Thus, when the plates 19, 21, and 22 are mounted in the camera body 13 as shown in FIGS. 3 and 4, the second contact 22y, together with the shutter release contact 19x, acts as the release switch RLS SW , and the upper contact 21x of the photometric switch plate 21 is positioned between these two contact terminals. A common conductive plate 12 having a first DX contact 12b is fixed on the camera body 13, and a separate second DX contact 12a is fixed to the camera body 13 near the first DX contact 12b. As shown in FIGS. 2 and 3, a film cartridge 11, to be placed in a cartridge chamber of the camera body 13, is provided with a DX code conductive pattern 11d on the outer surface thereof. DX code conductive patterns used on film cartridges have standardized binary code patterns of conductive portions and non-conductive portions, each distinctive DX code pattern representing a certain film speed. Within the many standard DX code patterns, some patterns are alike in one or more of the conductive or non-conductive portions of the pattern. More specifically, in some cases, similar film speeds are alike in at least some portions of the identifying DX code pattern. For example, a specific portion of the various DX code conductive patterns is non-conductive for all standard film speeds under ISO 400, and conductive for all speeds including ISO 400 and above. In the context of this specification, a DX code pattern portion in a predetermined position that defines an exclusive set of film speeds, is defined as a "shared DX code portion". The film cartridge 11 shown in FIGS. 1 through 3 is shown with a shared DX code portion 11e. FIG. 7 shows a schematic including a controller 25, release switch RLS SW , photometric switch PH SW , the common conductive plate 12, the first and second DX contacts 12b and 12a, and a shared DX code portion 11e. As shown in FIG. 7, inputs of the controller 25, connected to the release switch RLS SW and the photometric switch PH SW , are tied high. Furthermore, the DX contacts 12a, 12b, combined with the shared DX code portion 11e, act as a shared portion detection switch DX SW . An input of the controller 25, connected to the shared portion detection switch DX SW , is tied high. As shown in FIGS. 1 through 4, a connection to ground is provided for each of the switches RLS SW , PH SW , DX SW by the common conductive plate 12. A portion (DX contact 12b) of the shared portion detection switch DX SW is unitarily formed with the common conductive plate 12. The self-timer contact arm 19y of the release switch RLS SW , and the shutter release contact arm 19x of the photometric switch PH SW are connected to the common conductive plate 12 (as ground) by the brush 19c. The controller 25 controls a metering sensor (not shown) and self-timer circuit shown) when one of the shown switches is turned ON or OFF. As shown in FIGS. 1 through 3, when a film cartridge 11 is inserted in the camera body 13, the DX contacts 12a and 12b contact the shared DX code portion 11e of the DX code conductive pattern 11d of the film cartridge 11. Thus, using the shared portion detection switch DX SW , the controller 25 detects which group of two exclusive film speed groups (for example, one of "below ISO 400" or "ISO 400and above") to which a film inserted in the cartridge chamber belongs, according to the DX code shared portion 11e. If no film is inserted, the controller 25 defaults to one of the exclusive groups. As shown in FIGS. 5A and 8, during a normal shutter release operation, when the shutter release button 17 is half depressed, the shutter release contact arm 19x of the common switch plate 19 moves down to electrically contact the upper contact 21x of the photometric switch plate 21. As shown in FIG. 8, the controller 25 detects the closing of the photometric switch PH SW (that is, a portion of the common switch plate 19 contacts the photometric switch plate 21), and a photometric measurement is taken in response. Then, when the shutter release button 17 is further depressed, as shown in FIG. 5B, the shutter release contact arm 19x of the common switch plate 19, the upper contact 21x of the photometric switch plate 21, and the second contact 22y of the release switch plate 22 all contact. As shown in FIG. 8, the controller 25 detects the closing of both the photometric switch PH SW and the release switch RLS SW (that is, portions of the common switch plate 19 contact both of the photometric switch plate 21 and release switch 22), and the exposure operation is carried out in response. As shown in FIGS. 6 and 9, when the self-timer button 18 is depressed, the self-timer contact arm 19y of the common switch plate 19 moves accordingly down to electrically contact the first contact 22x of the release switch plate 22. Consequently, the controller 25 detects that the release switch RLS SW is closed (that is, that a portion of the common switch plate 19 contacts the shutter release plate 22), but that the photometric switch PH SW is not, and a preset self-timer circuit (not shown) is operated in response. In this case, even though the photometric switch PH SW is not turned ON, the photometric measurement is instructed by the self-timer circuit just prior to the exposure operation. As described above, a self-timer operation is readily carried out, and the switching device of the camera having a simple structure and improved assembly efficiency is provided. The present disclosure relates to subject matter contained in Japanese Patent Application No. HEI 06-326323, filed on Dec. 27, 1994, which is expressly incorporated herein by reference in its entirety.
A release switch is directly activated by a self-timer button, and a shutter release button first activates a photometric switch, then the release switch. The self-timer operation is carried out in response to the activation of only the release switch, a photometric operation is carried out in response to the activation of only the photometric switch, and a shutter release operation is carried out in response to the sequential activation of both the photometric switch and the release switch.
6
BACKGROUND OF THE INVENTION The present invention relates to a recording method by use of inks, and more particularly to a recording method by use of color ink, which method is particularly suitable for use in ink-jet printing. Conventionally there are known color printing methods employing inks each containing at least one of primary color colorants, that is, cyan, yellow and magenta colorants. In these color printing methods, highly water-soluble dyes capable of yielding excellent color tone are employed. However, those dyes have the shortcoming that they are poor in water resistance and light resistance even if they are used alone or in combination. In order to improve on the above conventional shortcoming, there has been proposed in Japanese Laid-open Patent Application Ser. No. 56-64992 a method of improving the water resistance of the recorded images by applying a polycationic agent to the surface of a recording sheet. By this method, the water resistance of the recorded images can be improved. However, the light resistance of the images becomes poor. The result is that the overall quality of the recorded images cannot be improved by this method. SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a recording method by use of inks, which method is capable of yielding color images with totally improved image quality, in particular, having high water resistance and high light resistance. According to the present invention, the above object is attained by a recording method in which there are employed an aqueous ink comprising at least one dye selected from the group consisting of the following dyes (a) through (d), and a recording medium containing at least one component selected from the group consisting of water-soluble salts of metals with an ion valence of 2 or more, alkyl amines, polyamines and quaternary ammonium salts. (a) pyrazolone azo dyes of the following formula I ##STR1## where M + represents Li + , Na + , K + , Cs + , NH 4 + or NR 4 1+ (in which R 1 represents an alkyl group), X 1 represents F, Cl, Br, I or hydrogen, and Y 1 represents hydrogen, an alkyl group or --COO--M + . (b) phthalocyanine sulfonate dyes of the following formula II ##STR2## where M + is the same as that defined in the formula I, and m is an integer of 2 to 4. (c) xanthene dyes of the following formula III or IV ##STR3## where M represents Li, Na, K, Cs, NH 4 or NR 4 1 (in which R 1 represents an alkyl group), X 2 represents Br, I or Cl, and Y 2 represents Br, I or Cl. ##STR4## where M is the same as that in the formula III, and R 2 represents hydrogen or an alkyl group. (d) azo dyes of the following formula V or VI ##STR5## wherein n is an integer of 0 or 1, X 3 represents hydrogen or --NH 2 , Y 3 represents hydrogen or --NHR 1 (in which R 1 represents an alkyl group), Z represents hydrogen, --OH or --COOM, and R 3 represents hydrogen, an alkyl group or --SO 3 M (in which M is the same as that defined in formula III); ##STR6## wherein X 4 represents hydrogen, --SO 3 M or --COOM (in which M is the same as that defined in the formula III). DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Representative pyrazolone azo dyes of the previously described formula I are, for example, C.I. Acid Yellow 17 and C.I. Acid Yellow 23. The former is the dye with X 1 being Cl and Y 1 being a methyl group in the formula I, and the latter is the dye with X 1 being hydrogen, and Y 1 being --COONa. Both dyes are in the form of a sodium sulfonate. Representative phthalocyanine sulfonate dyes of the previously described formula II are, for example, C.I. Direct Blue 87 and C.I. Acid Blue 249. The former is the dye with M + being Na + , and m being 3 in the formula II, and the latter is the dye with M + being Na + and m being 4 in the formula II. Representative dyes of the previously described xanthene dyes are, for example, C.I. Acid Red 52, C.I. Acid Red 92, C.I. Acid Red 94 and C.I. Acid Red 289. Representative azo dyes of the previously described formula V or VI are C.I. Acid Red 143, C.I. Acid Red 254, C.I. Acid Red 274 and C.I. Acid Red 260. In the present invention, as the metal salts to be applied to the surface of the recording medium or to be contained in the recording medium for treating the recording medium, the following can be employed: calcium chloride, calcium sulfate, calcium nitrate, magnesium chloride, magnesium sulfate, magnesium nitrate, aluminum chloride, aluminum sulfate, aluminum nitrate, barium chloride, barium nitrate, ferrous chloride, strontium chloride, strontium nitrate, stannous chloride, stannous fluoride, gallium chloride, gallium sulfate and gallium nitrate. When one of the above metal salts is employed as a treatment agent for the recording medium in the present invention, it is preferable that it be contained in the recording medium in an amount of 0.2 g/m 2 or more, more preferably in an amount of 0.5 g/m 2 or more. As the treatment agent for the recording medium, the following alkyl amine salts can also be employed: decylamine acetate, undecylamine acetate, dodecylamine acetate, tridecylamine acetate, tetradecylamine acetate, pentadecylamine acetate, hexadecylamine acetate, heptadecylamine acetate, octadecylamine acetate, nonadecylamine acetate and eicosylamine acetate. When the above alkyl amine salts are employed as the treatment agent in the present invention, it is preferable that the agent be contained in the recording medium in an amount of 0.1 g/m 2 or more. As the treatment agent for the recording medium, the following polyamines can also be employed: polyamide polyamine resin, polyamide-polyamine-epichlorohydrin resin, and quaternary cationic bridged polymers prepared by the reaction of the acetic acid salt or hydrochloric acid salt of polydimethylaminoethyl methacrylate and epichlorohydrin. When the above polyamines are employed as the treatment agent in the present invention, it is preferable that the agent be contained in the recording medium in an amount of 0.1 g/m 2 or more. As the treatment agent for the recording medium, the following quaternary ammonium salts can also be employed: cetyltrimethyl ammonium bromide, cetyltrimethyl ammonium chloride, alkylisoquinolium bromide, alkylisoquinolium chloride, hexadodecyltrimethyl ammonium bromide and hexadodecyltrimethyl ammonium chloride. When the above quaternary ammonium salts are employed as the treatment agent in the present invention, it is preferable that the agent be contained in the recording medium in an amount of 0.1 g/m 2 or more. The above treatment agents can be contained in the recording medium or applied thereto, for example, by one of the following methods: (1) The agent is contained when the recording medium is made. (2) The agent is contained in the surface layer of the recording medium. (3) The agent is applied to the recording medium. The images recorded on the thus treated recording medium by the ink containing one of or any combination of the previously described dyes are improved on the water resistance and light resistance thereof. Of the above described treatment agents, aluminum chloride, calcium chloride and octadecylamine acetate are particularly effective for improvement of the water resistance and light resistance of the recorded images. The inks employed in the present invention are particularly useful for ink-jet recording. These inks are useful not only for ink-jet recording, but also for use with conventional writing instruments. BRIEF DESCRIPTION OF THE DRAWING The drawing is a schematic representation illustrating a representative process according to this invention. Embodiments of an ink recording method according to the present invention will now be explained by referring to the following examples: EXAMPLE 1 In a 5 wt.% aqueous solution of aluminum chloride, there was immersed a commercially available recording sheet for ink-jet recording with a size degree of 0 sec, a brightness of 80 degrees (measured by a testing method for brightness by Hunter of paper and pulp in accordance with the Japanese Industrial Standard P 8123) and with a surface pH of 8, whereby the recording sheet was coated with the aluminum chloride with a deposition of 1.5 g/m 2 when dried, so that a recording medium for use in the present invention was prepared. The following inks were prepared in accordance with the following respective formulations: ______________________________________ Parts by Weight______________________________________Ink A (magenta)C.I. Acid Red 92 3(commercially available fromDaiwa Dyestuff Mfg. Co., Ltd.)Glycerin 8Diethylene glycol 24Deltop 33 0.5(commercially available fromTakeda Chemical Industries, Ltd.)Pure Water 56.5Ink B (cyan)Copper phthalocyanine tetrasulfonic acid 3(commercially available fromSumitomo Chemical Co., Ltd.)Glycerin 8Diethylene glycol 24Deltop 33(commercially available from 0.5Takeda Chemical Industries, Ltd.)Pure Water 56.5Ink C (yellow)C.I. Acid Yellow 23 3(commercially available fromDaiwa Dyestuff Mfg. Co., Ltd.)Glycerin 8Diethylene glycol 24Deltop 33 0.5(commercially available fromTakeda Chemical Industries, Ltd.)Pure Water 56.5______________________________________ The above inks were ejected individually or in such combinations as shown in Table 1 from a nozzle with a diameter of 60 μm at a speed of 17 m/sec to form dot images on the above-treated recording sheet. The water resistance of the dot images was determined by immersing the dot-image-bearing recording sheets in water at a temperature of 30° C. for 1 minute, 5 minutes after the formation of the dot images by each ink, and then measuring the difference between the image density of the dot images before the immersion and the image density after the immersion, thereby assessing the ratio of the fading of the dot images. The colors of the dot images were evaluated by a GATF color evaluation method, by which the hue error and change in greyness of the dot images were assessed. The light resistance of the dot images was determined by exposing the dot images to the light of a carbon arc for 3 hours and assessing by a fade meter the ratio of the fading of the images caused by the exposure. The results are shown in Table 1. For comparison, dot images were formed in the same manner as described above on the same recording sheet as that employed in Example 1, but which was not treated by the aqueous solution of aluminum chloride, and were then subjected to the same tests for assessing the water resistance, the hue error and change in greyness and the light resistance of the dot images. The results are also shown in Table 1. TABLE 1______________________________________ Treated Untreated Paper Paper______________________________________Magenta Ink A Ink A______________________________________Water Resistance 9.0 29.6(Fading ratio)Light Resistance 5.8 10.7(Fading ratio)Hue Error 56.8 48.9Greyness 8.1 6.1Drying Time (sec) 2.0/less 2.0/less______________________________________Cyan Ink B Ink B______________________________________Water Resistance 4.5 32.0(Fading ratio)Light Resistance(Fading ratio) 0 1.0Hue Error 35.0 34.0Greyness 18.0 16.0Drying Time (sec) 2.0/less 2.0/less______________________________________Yellow Ink C Ink C______________________________________Water Resistance 18.6 72.6(Fading ratio)Light Resistance 2.8 4.1(Fading ratio)Hue Error 9.1 11.6Greyness 5.7 5.5Drying Time (sec) 2.0/less 2.0/less______________________________________ Ink A + Ink A +Mixed Color (Red) Ink C Ink C______________________________________Water Resistance 19.0 70.0(Fading ratio)Light Resistance 6.5 10.0(Fading ratio)______________________________________ Ink A + Ink A +Mixed Color (Blue) Ink B Ink B______________________________________Water Resistance 10.0 28.0(Fading ratio)Light Resistance 6.0 11.0(Fading ratio______________________________________ Ink B + Ink B +Mixed Color (Green) Ink C Ink C______________________________________Water Resistance 19.0 73.0(Fading ratio)Light Resistance 3.0 3.0(Fading ratio)______________________________________ EXAMPLE 2 An aqueous solution containing 0.6 wt.% of octadecylamine acetate and 2 wt.% of polyvinyl alcohol was applied to a recording sheet with a size degree of 4 sec, a brightness of 82 degrees (measured by a testing method for brightness by Hunter of paper and pulp in accordance with the Japanese Industrial Standard P 8123) and with a surface pH of 5.5, whereby the solid components of the solution were deposited in an amount of 5 g/m 2 on the recording sheet when dried, so that a recording medium for use in the present invention was prepared. The following inks were prepared by mixing the following respective components in accordance with the following respective formulations: ______________________________________ Parts by Weight______________________________________Ink D (magenta)C.I. Acid Red 254 3(commercially available fromNippon Kayaku Co., Ltd.)Glycerin 8Diethylene glycol 24Deltop 33(commercially available fromTakeda Chemical Industries, Ltd.) 0.5Pure Water 64.5Ink E (cyan)Copper phthalocyanine trisulfonic acid 3(commercially available fromDaiwa Dyestuff Mfg. Co., Ltd.)Glycerin 8Diethylene glycol 24Deltop 33 0.5(commercially available fromTakeda Chemical Industries, Ltd.)Pure Water 64.5Ink F (yellow)C.I. Acid Yellow 17 3(commercially available fromDaiwa Dyestuff Mfg. Co., Ltd.)Glycerin 8Diethylene glycol 24Deltop 33 0.5(commercially available fromTakeda Chemical Industries, Ltd.)Pure Water 64.5______________________________________ The above inks were ejected individually or in such combinations as shown in Table 2 from a nozzle with a diameter of 60 μm at a speed of 17 m/sec, thereby forming dot images on the above-treated recording medium. The water resistance, the hue error and change in greyness and the light resistance of the dot images were determined in the same manner as in Example 1. The results are shown in Table 2. For comparison, dot images were formed on the above recording sheet without the above described treatment, in the same manner as in Example 1, and were then subjected to the same tests for assessing the water resistance, the hue error and change in greyness and the light resistance thereof. The results are also shown in Table 2. TABLE 2______________________________________ Treated Untreated Paper Paper______________________________________Magenta Ink D Ink D______________________________________Water Resistance 10.0 40.0(Fading ratio)Light Resistance 1.0 3.0(Fading ratio)Hue Error 40.3 37.5Greyness 15.3 16.2Drying Time (sec) 2.0/less 2.0/less______________________________________Cyan Ink E Ink E______________________________________Water Resistance 0 29.0(Fading ratio)Light Resistance 2.6 1.0Hue Error 31.8 32.1Greyness 15.4 18.4Drying Time (sec) 2.0/less 2.0/less______________________________________Yellow Ink F Ink F______________________________________Water Resistance 27.0 60.0(Fading ratio)Light Resistance 0 3.5(Fading ratio)Hue Error 9.5 9.5Greyness 5.0 4.5Dryness Time (sec) 2.0/less 2.0/less______________________________________ Ink D + Ink D +Mixed Color (Red) Ink F Ink F______________________________________Water Resistance 25.0 60.0(Fading ratio)Light Resistance 1.0 3.5(Fading ratio)______________________________________ Ink D + Ink D +Mixed Color (Blue) Ink E Ink E______________________________________Water Resistance 10.0 40.0(Fading ratio)Light Resistance 2.5 3.0(Fading ratio)______________________________________Ink E + Ink E +Mixed Color (Green) Ink F Ink F______________________________________Water Resistance 24.0 60.0(Fading ratio)Light Resistance 3.0 3.5(Fading ratio)______________________________________ EXAMPLE 3 In a 5 wt.% aqueous solution of calcium chloride, there was immersed a commercially available recording sheet for ink-jet recording with a size degree of 0 sec, a brightness of 80 degrees (measured by a testing method for brightness by Hunter of paper and pulp in accordance with the Japanese Industrial Standard P 8123) and with a surface pH of 8, which was the same recording sheet as that employed in Example 1, whereby the recording sheet was coated with the calcium chloride with a deposition of 3.5 g/m 2 when dried, so that a recording medium for use in the present invention was prepared. A magenta Ink G was prepared in accordance with the following formulation: ______________________________________Ink G (magenta) Parts by Weight______________________________________C.I. Acid Red 289 3(commercially available fromDaiwa Dyestuff Mfg. Co., Ltd.)Glycerin 8Diethylene glycol 24Deltop 33(commercially available fromTakeda Chemical Industries, Ltd.) 0.5Pure Water 64.5______________________________________ By use of the above Ink G, a mixed red ink prepared by mixing Ink C (yellow) (prepared in Example 1) and the Ink G and a mixed blue ink prepared by mixing Ink B (cyan) (prepared in Example 1) and the above Ink G, dot images were formed on the above prepared recording medium and were then subjected to the same tests for assessing the water resistance, the hue error and change in greyness and the light resistance of the dot images as in Example 1. The results are shown in Table 3. For comparison, dot images were formed on the recording sheet without the above treatment, in the same manner as in Example 1, and were then subjected to the same tests for assessing the water resistance, the hue error and change in greyness and the light resistance thereof. The results are also shown in Table 3. EXAMPLE 4 In a 3 wt.% aqueous solution of tetradecylamine acetate, there was immersed a recording sheet with a size degree of 4 sec, a brightness of 82 degrees (measured by a testing method for brightness by Hunter of paper and pulp in accordance with the Japanese Industrial Standard P 8123) and with a surface pH of 5.5, which was the same recording sheet as that employed in Example 2, whereby the recording sheet was coated with the tetradecylamine acetate with a deposition of 1.0 g/m 2 when dried, so that a recording medium for use in the present invention was prepared. A magenta Ink H was prepared in accordance with the following formulation: ______________________________________Ink H (magenta) Parts by Weight______________________________________C.I. Acid Red 274 3(commercially available fromNippon Kayaku Co., Ltd.)Glycerin 16Diethylene glycol 16Deltop 33 0.5(commercially available fromTakeda Chemical Industries, Ltd.)Pure Water 64.5______________________________________ By use of the above Ink H, a mixed red ink prepared by mixing Ink F (yellow) (prepared in Example 2) and the Ink H and a mixed blue ink prepared by mixing Ink E (cyan) (prepared in Example 2) and the above Ink H, dot images were formed on the above prepared recording medium and were then subjected to the same tests for assessing the water resistance, the hue error and change in greyness and the light resistance of the dot images as in Example 1. The results are shown in Table 3. For comparison, dot images were formed on the same untreated recording sheet as that employed in Example 2, in the same manner as in Example 1, and were then subjected to the same tests for assessing the water resistance, the hue error and change in greyness and the light resistance thereof. The results are also shown in Table 3. EXAMPLE 5 In a 7 wt.% aqueous solution of aluminum chloride, there was immersed the same recording sheet as that employed in Example 2, whereby the recording sheet was coated with the aluminum chloride with a deposition of 4 g/m 2 when dried, so that a recording medium for use in the present invention was prepared. A magenta Ink I was prepared in accordance with the following formulation: ______________________________________Ink I (magenta) Parts by Weight______________________________________C.I. Acid Red 143 5(commercially available fromNippon Kayaku Co., Ltd.)Glycerin 6Diethylene glycol 12Deltop 33 0.5(commercially available fromTakeda Chemical Industries, Ltd.)Pure Water 75.5______________________________________ By use of the above Ink I, a mixed red ink prepared by mixing INk C (yellow) and the Ink I and a mixed blue ink prepared by mixing Ink B (cyan) and the above Ink I, dot images were formed on the above prepared recording medium and were then subjected to the same tests for assessing the water resistance, the hue error and change in greyness and the light resistance of the dot imges as in Example 1. The results are shown in Table 3. For comparison, dot images were formed on the same untreated recording sheets as that employed in Example 2, in the same manner as in Example 1, and were then subjected to the same tests for assessing the water resistance, the hue error and change in greyness and the light resistance thereof. The results are also shown in Table 3. EXAMPLE 6 In a 4 wt.% aqueous solution of aluminum chloride, there was immersed the same recording sheet as that employed in Example 1, whereby the recording sheet was coated with the aluminum chloride with a deposition of 3.0 g/m 2 when dried, so that a recording medium for use in the present invention was prepared. A magenta Ink J was prepared in accordance with the following formulation: ______________________________________Ink J (magenta) Parts by Weight______________________________________C.I. Acid Red 94 4.5(commercially available fromHodogaya Chemical Co., Ltd.)Glycerin 12Diethylene glycol 25Deltop 33 0.5(commercially available fromTakeda Chemical Industries, Ltd.)Pure Water 58______________________________________ By use of the above ink J, a mixed red ink prepared by mixing Ink C (yellow) and the Ink J and a mixed blue ink prepared by mixing Ink B (cyan) and the above Ink J, dot images were formed on the above prepared recording medium and were then subjected to the same tests for assessing the water resistance, the hue error and change in greyness and the light resistance of the dot images as in Example 1. The results are shown in Table 3. For comparison, dot images were formed on the same untreated recording sheet as that employed in Example 1, in the same manner as in Example 1, and were then subjected to the same tests for assessing the water resistance, the hue error and change in greyness and the light resistance thereof. The results are also shown in Table 3. TABLE 3______________________________________ Treated Untreated Paper Paper______________________________________Example 3Magenta Ink G Ink G______________________________________Water Resistance 30.0 56.0(Fading ratio)Light Resistance 2.0 12.0(Fading ratio)Hue Error 12.2 9.8Greyness 17.2 20.4______________________________________ Ink C + Ink C +Mixed Color (Red) Ink G Ink G______________________________________Water Resistance 30.0 75.0(Fading ratio)Light Resistance 3.0 12.0(Fading ratio)______________________________________ Ink B + Ink B +Mixed Color (Blue) Ink G Ink G______________________________________Water Resistance 30.0 56.0(Fading ratio)Light Resistance 2.0 12.0(Fading ratio)______________________________________Example 4Magenta Ink H Ink H______________________________________Water Resistance 18.0 25.0(Fading ratio)Light Resistance 5.0 12.8(Fading ratio)Hue Error 31.0 36.1Greyness 17.4 19.4______________________________________ Ink H + Ink H +Mixed Color (Red) Ink F Ink F______________________________________Water Resistance 30.0 75.0(Fading ratio)Light Resistance 5.0 12.8(Fading ratio)______________________________________ Ink E + Ink E +Mixed Color (Blue) Ink H Ink H______________________________________Water Resistance 18.0 30.0(Fading ratio)Light Resistance 5.0 13.0(Fading ratio)______________________________________Example 5Magenta Ink I Ink I______________________________________Water Resistance 15.0 60.0(Fading ratio)Light Resistance 0 0.5(Fading ratio)Hue Error 44.5 40.4Greyness 23.7 23.2______________________________________ Ink I + Ink I +Mixed Color (Red) Ink C Ink C______________________________________Water Resistance 19.0 73.0(Fading ratio)Light Resistance 3.0 4.0(Fading ratio)______________________________________ Ink I + Ink I +Mixed Color (Blue) Ink B Ink B______________________________________Water Resistance 17.0 60.0(Fading ratio)Light Resistance 0 1.0(Fading ratio)______________________________________Example 6Magenta Ink J Ink J______________________________________Water Resistance 5.0 5.0(Fading ratio)Light Resistance 10.0 15.0(Fading ratio)Hue Error 40.0 35.0Greyness 8.0 8.0______________________________________ Ink J + Ink J +Mixed Color (Red) Ink C Ink C______________________________________Water Resistance 19.0 73.0(Fading ratio)Light Resistance 10.0 15.0(Fading ratio)______________________________________ Ink J + Ink J +Mixed Color (Blue) Ink B Ink B______________________________________Water Resistance 5.0 35.0(Fading ratio)Light Resistance 12.0 15.0(Fading ratio)______________________________________ EXAMPLE 7 By dispersing the following components, a dispersion was prepared. ______________________________________ Parts by Weight______________________________________Calcium carbonate 17Zinc chloride 4Styrene-butadiene copolymer 19Latex (Solid components)Polyvinyl alcohol 2Water 58______________________________________ The above dispersion was applied to one side of a sheet of high quality paper with a 12 g/m 2 deposition of the solid components (when dried) by a doctor blade and was then dried at 105° C. for 5 minutes. Thereafter, the coated sheet was subjected to calendering to make the surface of the coated sheet smooth. Ink A (magenta), Ink B (cyan), Ink C (yellow) were individually ejected from a nozzle with a diameter of 60 μm at a speed of 17 m/sec, so that dot images were formed on the above treated sheet. The thus formed dot images were then subjected to the same tests as in Example 1 for assessing the water resistance, the hue error and change in greyness and the light resistance of the dot images. The results are shown in Table 4. For comparison, a comparative dispersion was prepared in the same manner as mentioned above in accordance with the following formulation: ______________________________________ Parts by Weight______________________________________Calcium carbonate 17Styrene-butadiene copolymer 19Latex (Solid components)Polyvinyl alcohol 2Water 58______________________________________ In the above formulation, only zinc chloride was eliminated from the first-mentioned formulation. The thus prepared comparative dispersion was applied to one side of a sheet of the same high quality paper as mentioned above with a 12 g/m 2 deposition of the solid components (when dried) by a doctor blade and was then dried at 105° C. for 5 minutes. Thereafter the comparative coated sheet was subjected to calendering in the same manner mentioned above, thereby making the surface thereof smooth. Ink A, Ink B and Ink C were individually ejected from the same nozzle at the same speed as mentioned above, thereby forming dot images on the comparative coated sheet. The dot images formed on the comparative coated sheet were then subjected to the same tests for assessing the water resistance, the hue error and change in greyness and the light resistance thereof. The results are also shown in Table 4. TABLE 4______________________________________ Example Comparative Example Ink Ink Ink Ink Ink Ink A B C A B C______________________________________Water Resistance 3.5 0 17.3 75.3 34.5 70.5(Fading ratio)Light Resistance 5.0 1.0 1.9 32.0 8.2 5.3(Fading ratio)Hue Error 43.0 26.3 9.0 44.0 25.8 11.3Greyness 6.7 18.2 6.2 5.8 19.1 5.7Drying Time 2 2 2 2 2 2(sec)/less______________________________________ EXAMPLE 8 By dispersing the following components, a dispersion was prepared. ______________________________________ Parts by Weight______________________________________Silica (Oil adsorption 130) 10Aluminum chloride 4Acryl latex (solid components) 3Polyvinyl alcohol 13Starch 3Water 67______________________________________ The above dispersion was applied to one side of a sheet of acetate film with a thickness of 75 μm, with a 8 g/m 2 deposition of the solid components (when dried) by an air-knife coating method and was then dried at 90° C. for 10 minutes, whereby a recording medium for ink-jet printing for use in the present invention was prepared. Ink D (magenta), Ink E (cyan) and Ink F (yellow) were individually ejected from a nozzle with a diameter of 60 μm at a speed of 17 m/sec, so that dot images were formed on the above prepared recording medium. The thus formed dot images were then subjected to the same tests as in Example 1 for assessing the water resistance, the hue error and change in greyness and the light resistance of the dot images. The results are shown in Table 5. For comparison, a comparative dispersion was prepared in the same manner as mentioned above in accordance with the following formulation: ______________________________________ Parts by Weight______________________________________Silica (Oil adsorption 130) 10Acryl latex (solid components) 3Polyvinyl alcohol 13Starch 3Water 67______________________________________ In the above formulation, only aluminum chloride was eliminated from the first-mentioned formulation in Example 8. The thus prepared comparative dispersion was applied to one side of a sheet of the same acetate film as mentioned above with a 8 g/m 2 deposition of the solid components (when dried) by the same air-knife coating method and was then dried at 90° C. for 10 minutes, whereby a comparative recording medium was prepared. Ink D, Ink E and Ink F were individually ejected from the same nozzle at the same speed as mentioned above on the comparative recording medium, thereby forming dot images thereon. The dot images formed on the comparative recording medium were then subjected to the same tests as in Example 1 for assessing the water resistance, the hue error and change in greyness and the light resistance thereof. The resulted are also shown in Table 5. TABLE 5______________________________________ Example Comparative Example Ink Ink Ink Ink Ink Ink D E F D E F______________________________________Water Resistance 73 0 20.0 53 32.0 73.2(Fading ratio)Light Resistance 1.5 0.5 1.0 4.8 2.7 5.2(Fading ratio)Hue Error 28.3 24.2 9.1 25.5 25.1 8.9Greyness 14.1 19.2 6.2 15.3 18.2 5.3______________________________________ As can be seen from the above described embodiments of the recording method according to the present invention and the comparative examples, the present invention provides a recording method capable of yielding color images with totally improved image quality, in particular, having high water resistance and high heat resistance.
A recording method by use of an ink is disclosed, in which images are formed by an aqueous ink comprising at least one dye selected from the group consisting of a pyrazolone azo dye, a phthalocyanine sulfonate dye, a xanthene dye and an azo dye on a recording medium containing at least one component selected from the group consisting of a water-soluble metal salt whose metal has an ion valence of 2 or more, an alkyl amine and a quaternary ammonium salt.
2
This is a division of application Ser. No. 453,241, filed Mar. 21, 1974. BACKGROUND OF THE INVENTION With the advent of high power gas lasers, the amount of power lost through inefficient operation is continuously increasing. This problem is important not only because of economic considerations, but also because the amount of energy being dissipated as heat has serious deleterious effects on the laser materials, resulting in degradation of its components. Maximum laser efficiency, can, in principle, be best achieved by tailoring the energy requirements to obtain excitation of the metastable state or the upper laser level. But unfortunately, this theory is generally inapplicable for existing gas lasers which employ conventional methods of gaseous discharge since in these cases, the average electron energy is largely dictated by the conditions and requirements for maintaining a sustained discharge. For CO 2 lasers involving vibration-rotation transitions, operation at high pressures is generally more desirable. By raising the gas pressure, the laser power output can conveniently be increased without increasing the cavity dimensions, thereby eliminating the need for using long cavities which are difficult to manage. Unfortunately, at high gas pressures, uniformly distributed electrical discharges are very difficult to maintain and laser oscillation may terminate because of arcing and localized current build up. An example of arcing being caused by high gas pressures occurs in a pulsed CO 2 laser where the high density of the active molecules requires that the energy per pulse per unit of volume increase linearly with the gas pressure. The increase in gas pressure becomes apparent, if it is recognized that population of the upper energy levels is generally induced by three methods. In the first method electrons collide directly with CO 2 molecules. A second method involves an intermediate reaction and requires traces of a secondary gas, such as N 2 within the discharge chamber. The electrons first collide with the N 2 molecules and the excited N 2 molecules, in turn, collide with ground state CO 2 molecules. Each collision may add photons to the laser field, and thus the second method is often used in conjunction with the first to increase the power output of the laser. Without the presence of the secondary gas this intermediate reaction does not occur since after contributing photons to the laser field, the excited CO 2 molecules are left in the lower state of laser transition. However, the molecules eventually decay to the ground state at which point they can be re-excited by collision with the N 2 molecules. A third method may also increase the power output of the laser and involves deactivation of the lower laser levels by addition of a gas which depopulates the lower energy levels. The repitition rate of all the molecular collisions is directly related to the gas pressure and consequently, the maximum laser power available per unit volume depends on the operating pressure. Therefore, if high output power in a pulsed CO 2 laser is desired, it is accompanied by an increase in pressure. This increased pressure can cause arcing since although the voltage drop across a cathode is essentially constant, a negative electrode within a plasma does not provide a uniform discharge distribution. Intense plasma distributed locally creates a bright or hot cathode spot having an energy input per unit area which increases rapidly with pressure to cause arcing. Also, the thickness of the cathode drop region decreases as the pressure increases causing the energy dissipated per unit volume in the cathode drop region to increase, resulting in current build up which, in turn, causes arcing. For all these reasons, the tendency of a glow discharge to change into an arc increases rapidly as the gas pressure is raised. One solution to this problem has recently been proposed in an article titled "Transversely Excited Atmospheric Pressure Carbon Dioxide Laser" by A. J. Beaulieu. This article relates to a pulsed atmospheric pressure He--N 2 --CO 2 laser wherein a transversely excited discharge of short duration is maintained between the large flat anode and a row of resistive pin cathodes. A large number of these resistors are used to impede localized current build up which prevent local arcing of plasma and achieve a laser output of 2J per pulse at a repetition rate of 1,000 PPS and an efficiency of 17%. The current pulse for exciting the laser is obtained by discharging a 0.02 microfarad capacitor which had been charged to 17,000 volts. However, the discharge stability obtained was accompanied by a reduction of efficiency due to energy losses in the resistor network and therefore the Beaulieu device also has a considerable energy loss during its operation. SUMMARY OF THE INVENTION An object of the invention is to reduce the energy requirements of a high pressure gas laser. Briefly, the present invention overcomes the difficulties common to high pressure gas lasers by permitting electron energy to be chosen largely based on the energy considerations required to accelerate electrons instead of energy/pressure requirements necessary to supply the electrons. One embodiment of the invention consist of a row of auxiliary electrode means, each electrode means consisting of a cathode and anode which independently maintains an auxiliary discharge. A principal discharge is maintained between a large flat or cylindrical anode and a virtual cathode which is created within the body of a glow plasma produced by the auxiliary electrodes. A principal discharge is maintained transverse to the auxiliary discharge and independently thereof to accelerate the electrons and effect the number of collisions between the electrons and the gas molecules. With the auxiliary discharge produced by the plasma cathode supplying the required electrons, and the accelerating electric field being independently controlled by the principal discharge, the present device permits a wider range of operating parameters of a CO 2 laser than is available through prior art devices. In a specific embodiment, the auxiliary electrodes can consist of brush cathodes, gas-fed hollow cathodes, or simple wire mesh. To prevent current concentration and arcing, distribution resistors or simple solid state constant current devices can be placed in series with the auxiliary electrodes. Since the power required to maintain the auxiliary discharge constitutes only a small portion of the total power input, energy dissipated by the distribution resistors is considerably less than the energy dissipated by resistors placed in the primary discharge circuit. BRIEF DESCRIPTION OF THE DRAWING Other objects, advantages and novel features of the present invention will appear from a reading of the following detailed description of the invention when considered in conjunction with the accompanying drawings, in which: FIG. 1 is a schematic illustration of an embodiment of the invention when energized from a DC source; FIG. 2 is a prespective view of a brush hollow cathode used in the embodiment of FIG. 1; FIG. 3 is a cross-sectional view of the brush hollow cathode of FIG. 2; and FIG. 4 is a schematic illustration another form of the invention when energized from an AC source. DETAILED DESCRIPTION OF THE INVENTION Referring to the drawings, and initially to FIG. 1, there is shown a general view 20 of an embodiment of the invention which can be used with a gaseous discharge device. It should be understood that the drawing is for purposes of illustration only and is not drawn to scale. An envelope 21 is shown by dotted lines which describe generally the outline of a laser cavity. Within the envelope 21, a principal discharge is maintained between a large flat or cylindrical anode 22 and virtual cathode 24 located within an auxiliary discharge region 25. The auxiliary discharge region 25 is produced by the combined effect of the individual discharges of electrodes 26-40, which are disclosed in detail in the discussion of FIGS. 2 and 3. Generally, however, these electrodes consist of stainless steel rectangular anodes, 42-56, and corresponding stainless steel tubes 58-72. A potential difference is maintained between anodes 42-56 and cathodes 58-72 and is derived from an auxiliary tap 73 on power source 74, auxiliary tap 73 having its positive terminal 77 connected to the rectangular anodes 42-56 by lead 75 and corresponding distribution resistors 76-90. It's negative terminal 78 is connected to tubes 58-72 via conductor 79. The power dissipated by distribution resistors 76-90 is a fraction of the power being supplied by primary source 74 due to the fact that the power requirements for the auxiliary electrodes 26-40 are only a fraction of that required for the main discharge. Anode 22 is connected to positive terminal 91 of power supply 74 by conductor 94, thus maintaining a potential difference between anode 22 and the virtual cathode 24. Mirrors 98 and 100 are of the conventional type used to promote oscillation and the laser output may be taken at the location of either mirror by appropriate selection of transmissive mirrors or windows, such as a mirror with a small aperture. In the case of CO 2 lasers, gas may be introduced into the glow discharge region 25 through the stainless steel tubes 58-72. A supply 102 is used to introduce CO 2 to the tubes 58-72 through duct 103 and thus to the auxiliary discharge region 25. If the CO 2 is drawn through the auxiliary electrodes into the discharge region 25, the gas pressure at the point where it is discharged through the cathodes is greater than in the discharge region 25; and the additional differential pressure aids in maximizing the cathode operation at high operating pressures. In this event, the gas can be withdrawn from the chamber by any means, such as a vent port 105 located behind the anode or elsewhere. An alternative way is to connect a vacuum pump 102 to the tubes 58-72 to pull the gas in the chamber through the capillaries resulting in the interior of the tubes being operated at a lower pressure relative to the discharge region 25. For the alternative method gas must be introduced into the chamber through port 105 and the tubes 58-72 are then used as the exhaust ports. The operation of the auxiliary discharge electrodes 26-40 will be more apparent upon a review of FIGS. 2 and 3 where a detailed drawing of electrode 26 is shown. Electrode structure 26 is shown with the stainless steel rectangular anode 42 being insulated from stainless steel tube 58 by means of a ceramic epoxy insulator 104. Once again, the potential difference is maintained between anode 42 and tube 58 by means of auxiliary tap 73 and distribution resistor 76. Extending from the end 106 of the epoxy insulator 104 is a plurality of stainless steel capillary tubes 108 which are electrically connected to tubular conductor 58 and thus also maintained at a potential difference relative to the rectangular anode 42. The capillary tubes 108 form a brush cathode which together with anode 42 create an auxiliary discharge region there between. CO 2 gas supplied through stainless steel tube 58 enters discharge region 25 through the capillaries 108. The electric field established between anode 42 and the capillaries 108 sometimes causes the plasma to enter the capillaries 108 depending on the pressure within the capillaries. Although capillaries 108 are shown, wire mesh could be used. In this event, the wire mesh would cover the opening in the end 106 of the epoxy insulator 104 while also being electrically connected to the tube 58. The only requirement for the wire mesh is that it contain apertures to allow the flow of gas between tube 58 and region 25. The plasma consists of a mixture of gas, ions and electrons. The ions return to the cathode. The electrons within the plasma travel to anode 22 and anodes 42, 44, 46, 48, 50, 52, 54, 56 and their acceleration depends on the magnitude of the electric field established by source 92. Thus the plasma generated by each electrode acts as a cathode and when all of the electrodes 26-40 are aligned as shown in FIG. 1, the virtual plasma cathode, approximately along line 24, develops. The movement of the electrons from the plasma cathode 24 to the anode 22 results in collisions between the accelerated electrons and the gas molecules and ions and these collisions initiate the lasing activity. As mentioned, in one mode of operation, traces of a secondary gas, such as nitrogen, must be present in the discharge chamber in order to populate the upper laser level. Nitrogen can be supplied to the discharge chamber by mixing it with the CO 2 gas. The electric field existing between anode 22 and virtual cathode 24 can be maintained by source 74 to select the electron acceleration independently of the power requirements for the auxiliary discharge electrodes 26-40. Collisions between the accelerated electrons and N 2 molecules causes population of the upper laser level of the CO 2 molecules and the frequency of these collisions is also related to the electric field. An atmospheric pressure laser is capable of continous wave or pulsed operation. However when the laser is used in the pulsed operation mode, inductances should be placed in series with the individual electrodes 26-40 to aid in uniform distribution of the current. The inductances are relatively loss free and eventually return the energy to the laser. Howeven, often this energy is returned after the laser activity is terminated, and thus the use of inductances does not always, increase the operational efficienty of the system. As an alternative to the inductances, a section of transmission line can be used. The transmission line has energy reflecting capabilities which introduces a delay and results in a flat top pulse. The structure shown in FIG. 1 is designed to operate with a DC power supply or pulsed supply and is practical only for reasonable power levels. When laser actvity in the multi-megawatt range is desired, a DC or pulsed power supply becomes restrictive. The structure shown in FIG. 4 is designed to operate from raw AC through a 3-phase 60 cycle per second transformer and the power supply problems associated with an AC system of this type are significantly less than its DC or pulsed counterpart. Anode 22 and virtual cathode 24 of FIG. 1 have been replaced in FIG. 4 by a symmetrical electrode structure which functions either as a cathode or anode, depending on the portion of the AC cycle in operation at a given instant. The structure of the auxiliary discharge electrodes 110-120 is identical to that shown in FIGS. 2 and 3, with the power for the electrodes 110-120 being derived in FIG. 4 from auxiliary taps 122-132 on high power transformers 134-138. The phases of the transformer windings 134-138 and the auxiliary windings 122-132 are shown by the conventional dot method. As mentioned, the electrodes 110-120 operate both as a cathode and anode and to aid in understanding this operation, electrode pair 114 and 120 is discussed in detail. The potential difference between cathode and anode of electrode 114 is maintained by auxiliary transformer tap 126. Similarly, auxiliary transformer tap 132 is used to generate the potential difference for electrode 120 thus enabling it to produce the required supply of electrons. High power transformer 138 alternately drives one of the electrodes 114 or 120 more positive than the other. During the period when electrode 114 is positive with respect to electrode 120, electrode 114 acts as the anode and electrode 120 as the cathode, with electrons traveling from electrode 120 to electrode 114 during this portion of the operating cycle. During the portion of the cycle which electrode 120 becomes positive relative to electrode 114, electrode 120 acts as the anode and electrode 114 as the cathode with electrons traveling from electrode 114 to electrode 120. The remaining electrode pairs operate in similar manner with each electrode operating as a cathode for a portion of the AC cycle and as an anode for other portions AC cycle. The electrons emitted by the cathode generally travels directly to the anode of the same electrode pair. Ocassionally, however electrons are diverted to one or more of the other positive electrodes. But the effect of this diversion of electrons is minimal since the electrons must have a return path to the cathode source of electrons. Thus a secondary anode accepts only a few extra electrons before it becomes saturated and refuses to accept additional electrons. To maintain a high plasma utilization within the active region, the spacing between the electrodes in each pair is maintained at a distance comparable to the diameter of the beam so that the plasma region outside of the central intersection 140 is kept at a minimum. The plasma region which is not common to all electrode pairs, such a region 142, represents a loss of power and efficiency, and should be corrected either by proper spacing of the electrodes or by designing mirrors large enough to encompass the outer plasma space. If not correct, the region such as 142 of plasma exterior to the common region 140 continues to lase but since these regions are effected by only one electrode pair operating for one-third of the total duty cycle, the lasing operation in these areas is discontinous and contains a high ripple component. The mirrors are not shown in FIG. 4 for purposes of clarity. The mirrors would be placed along an axis 147, which is directed into the page. Once again the laser output may be taken at the mirror locations. Thus, there is described improved method and apparatus which permits electron energy in a laser cavity to be chosen based on energy requirements for accelerating electrons rather than energy requirements for providing a sufficient number of electrons. By maintaining an auxiliary discharge to provide the necessary electrons to the laser and providing a transverse electric field to accelerate the electrons, the excitation of the laser can be controlled independently of the requirements for maintaining the sustained discharge. Obviously, many modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically described.
The present invention relates to improved method and structure for producing an electric discharge in a laser cavity which eliminates arcing and permits electron energy to be chosen based on energy requirements for accelerating the electrons rather than energy and/or pressure requirements for supplying electrons. An auxiliary discharge is maintained to provide the electrons necessary for laser excitation. A transverse electric field is then superimposed to impart the energy required to accelerate the electrons.
7
BACKGROUND OF THE INVENTION The present invention relates to a biodegradable crosslinked polymer having a chelating effect and a function to disperse an oily substance and an inorganic substance hardly soluble in water as well as showing excellent dispersion performance into water and further, the invention relates to a process for producing the crosslinked polymer. Still further, it relates to use of the crosslinked polymer, especially, relates to detergency enhanced by combining this crosslinked polymer with a detergent composition and, thence, a builder excellent in biodegradability and a detergent composition containing this builder. In addition, it relates to a biodegradable medicine, which may be used involving discharge into environment at a final stage, such as a fiber-treating agent, an inorganic pigment dispersant and a water treatment agent. When a builder is combined with a detergent, the chelating and dispersing effects of the builder increase detergency of the detergent. Preferable builders conventionally and widely used from viewpoints of performance, safety and price are condensed phosphates such as sodium tripolyphosphate and the like. However, since phosphorous compounds of these types are an origin of eutrophication for a river, lake, marsh and the like, their use has been limited in recent years and substitution of them is in rapid progress. At present, instead of the condensed phosphates such as sodium tripolyphosphate and the like, zeolite which is not problematic in the eutrophication and safety is used. However, the zeolite is not enough in builder performance and also, it is insoluble in water and, thence, its combination with a liquid type cleaner is not possible and precipitation with the washing may occur. On the other hand, instead of the above-described inorganic compounds, an organic compound, for example, a polyelectrolyte such as a polyacrylate and polymaleate has been used as a builder. The polyacrylate and polymaleate are superior in the builder performance, but there is a defect that they are poor in biodegradability. In Japanese Official Patent Provisional Publication, showa 54-52196, a polyacetal carboxylate has been proposed as a polymer type builder improved in biodegradability. The polyacetal carboxylate is not economical because of its high material cost and also, the process for producing the carboxylate is complicate and not of practical use. In Japanese Official Patent Provisional Publications, showa 63-305199 and 63-305200 and heisei 1-306411 and 2-36210, a water-soluble polymer made by polymerizing a monomer having at least two of an ethylenically unsaturated double bond has been proposed. A water-soluble polymer of this type, according to studies of the present inventors, is difficult in controlling the molecular structure and contains a considerable proportion of molecules not having a structure suitable to biodegradation, and therefore, there is a problem that this type polymer may contain an ingredient which does not undergo biodegradation at all or may require a long period of time for biodegradation. Graft polymers of polysaccharides with acrylic acid and the like in Japanese Official Patent Provisional Publication, showa 61-31497, and graft polymers of monosaccharides and/or oligosaccharides with acrylic acid and the like in Japanese Official Patent Provisional Publication, showa 61-31498, have been proposed. In the graft polymers of these types, only the parts of polysaccharides, monosaccharides and oligosaccharides undergo biodegradation, but the graft parts due to acrylic acid and the like have large molecular weights and do not undergo biodegradation. Like this, all of the forementioned polymers have defects and, therefore, any polymer satisfactory enough has not yet found. In the field of fiber-treating agents, a polyacrylate has been conventionally used by combining it with a chelating agent to elevate dispersing performance. In the field of inorganic pigment dispersants, a polyacrylate and a maleic acid-acrylic acid copolymer salt have been used to decrease the viscosity of a solution of dispersed slurry and to elevate the stability of viscosity. In the field of water treatment agents, a polymer such as polyacrylate, polymaleate and the like has been used instead of the conventional phosphine-based medicine as a scale suppressant of calcium carbonate. However, these polycarboxylic acid-based polymers show good performance in various kinds of use, but they have a defect, that is poor in biodegradability. SUMMARY OF THE INVENTION It is a first object of the present invention to provide a crosslinked polymer having chelating and dispersing effects, being excellent in dispersing performance into water, and being superior in biodegradability. A second object is to provide a process for producing such the crosslinked polymer with good efficiency or with a simple procedure and also, which is possible to practice industrially. A third object of this invention is to provide a builder which is able to increase detergency by combining with a detergent composition independent of this composition condition, and which can be decomposed by an organism such as a microorganism and the like, does not cause eutrophication when being excreted into a river, lake and marsh, does not accumulate in surplus, and is safe enough. Furthermore, a fourth object is to provide a detergent composition in which a builder of the above type is combined. Still further, a fifth object is to provide a biodegradable agent in use which involves discharge into environment at a final stage, for example, the use as a fiber-treating agent, an inorganic pigment dispersant, a water treatment agent or the like. The present inventors intensively studied about polymers having chelating and dispersing effects as well as hydrophilicity and excellent biodegradability. An important finding by us was that the chelating and dispersing effects are effectively afforded, if a water-soluble oligomer contains an ingredient having not the chelating and dispersing effects originally or having the effects slightly, but having a low molecular weight of a biodegradable grade in more than a certain extent and then, if a molecular weight increase is carried out by combining water-soluble oligomers of the above kind one another at positions on their main chains through bonds having the undermentioned biodegradable groups (II) and/or (III). This finding led to completion of this invention satisfactory for the forementioned requirements. Accordingly, the present invention provides a biodegradable hydrophilic crosslinked polymer; having a structure in which a bond having at least one of a group (II) represented by the chemical formula --CO--O-- and a group (III) represented by the chemical formula --CO--NH-- as a composition unit is formed among each of main chains, said main chains being made of a water-soluble oligomer which contains an ingredient having a molecular weight of 5,000 or less in 50% by weight or more and which has a functional group (I) represented by the general formula --COOM (herein, M denotes any one of a hydrogen atom, monovalent metal, divalent metal, trivalent metal, an ammonium group and organic amine group); showing a viscosity of 1,000 cP or less at 20° C. by a 20% by weight aqueous solution of said crosslinked polymer. The present invention provides a process for producing a biodegradable hydrophilic crosslinked polymer, of which 20% by weight aqueous solution shows a viscosity of 1,000 cP or less shown at 20° C., comprising a step of combining a water-soluble oligomer by a crosslinking agent: said water-soluble oligomer has an ingredient of 5,000 or less in molecular weight in 50% by weight or more and the functional group (I); and said crosslinking agent has either (not only) at least one of the groups (II) and (III), or (but also) is capable of forming at least one of the above-described groups (II) and (III). (hereinafter, this production process is sometimes referred to as "the later crosslinking process".) This later crosslinking process is a process, wherein the water-soluble oligomer is a water-soluble oligomer (A); which is made by polymerizing a monomer component, composed of 50 to 100 mole % of at least one monomer (a) selected from the group consisting of a monoethylenically unsaturated carboxylic acid of 3 to 6 in carbon number and salts of this acid, and a residual % of another monoethylenically unsaturated monomer (b) capable of copolymerizing with (a); and said water-soluble oligomer (A) comprises an ingredient having a molecular weight of 5,000 or less in 50% by weight or more and further, has the functional group (I); the crosslinking agent is a compound (B), which has at least two of the functional group (IV) capable of reacting with a functional group which the water-soluble oligomer (A) has, and which has either (not only) at least one of the groups (II) and (III) between said functional group (IV), or (but also) is capable of forming at least one of the groups (II) and (III) by a reaction of the functional group (IV) with the functional group which the water-soluble oligomer (A) has; the reaction of said water-soluble oligomer (A) with the compound (B) is carried out by using those in such amounts as the mole ratio between the functional group (IV) of the compound (B) to the functional group of the water-soluble oligomer (A) is shown by the equation; ##EQU1## The present invention also provides a builder being made by a biodegradable hydrophilic crosslinked polymer; having a structure in which a bond having at least one of a group (II) and a group (III) as a composition unit is formed among each of main chains, said main chains being made of a water-soluble oligomer which contains an ingredient having a molecular weight of 5,000 or less in 50% by weight or more and which has a functional group (I); showing a viscosity of 1,000 cp or less at 20° C. by a 20% by weight aqueous solution of said crosslinked polymer. This builder may be made by a hydrophilic crosslinked polymer produced by the forementioned crosslinking process. This invention further provides a detergent composition containing the above-described builder and a surfactant. This invention still further provides a fiber-treating agent, an inorganic pigment dispersant and a water treatment agent, which are made by containing the hydrophilic crosslinked polymer of this invention. The hydrophilic crosslinked polymer of this invention has a structure being crosslinked by a bond having at least one of the groups (II) and (III) as a composition unit. A main chain of this structure consists of only a carbon--carbon single bond or has a structure, of which main body is the carbon--carbon single bond. This main chain converts a water-soluble oligomer containing a molecular weight component, designed as described above, in a defined proportion by the crosslinked chain being cut. It is required that the water-soluble oligomer contains an ingredient having a molecular weight of 5,000 or less in 50% by weight or more. In a preferable case, the oligomer contains an ingredient having a molecular weight of from 300 to 5,000 in 50% by weight or more. If the ingredient having a molecular weight of 5,000 or less is less than 50% by weight, a portion not biodegradable may remain or the biodegradation takes a long period of time. Although, in a preferable case, the water-soluble oligomer contains an ingredient having a molecular weight of 300 to 5,000 in 50% by weight or more, if an ingredient having a molecular weight of 300 to 2,500 is contained in a major amount in the ingredient having a molecular weight of 300 to 5,000, the biodegradability is further favored. Each molecule of the water-soluble oligomers is required to have the functional group (I). This is because the functional group (I) reveals the chelating and dispersing effects. A content proportion of the functional group (I) in a crosslinked polymer is not especially specified, but a preferable content is 5 mmol per gram or more. If it is less than this, the chelating and dispersing effects may diminish. A bond having at least one of the groups (II) and (III) as a composition unit is a bond by which the group (II) or (III) directly combines with a carbon atom in a main chain, or a bond which comprises another intervening group between the group (II) or (III) and at least one carbon atom of the main chain. The here-described another intervening group may be of any kind and is not especially limited. A hydrophilic crosslinked polymer of this invention is required to have a viscosity of 1,000 cP or less at 20° C. by a 20% by weight aqueous solution of the crosslinked polymer, and a preferable viscosity is 500 cP or less. If the crosslinked polymer has a viscosity larger than 1,000 cP, the chelating and dispersing effects become unsatisfactory due to a decrease in dispersion performance and also, handling becomes hard. A hydrophilic crosslinked polymer of this invention is preferably obtained by the forementioned late crosslinking process, explained hereinafter. The water-soluble oligomer (A) is obtained by polymerizing monomer components, in which the monomer (a) is in a range of from 50 to 100 mol % and the monomer (b) is a residual part. If the monomer (a) is less than 50 mol %, in other words, if the monomer (b) is more than 50 mol %, the chelating and dispersing effects of an obtaining crosslinked polymer is unsatisfactory. To obtain the water-soluble oligomer (A) from the monomers (a) and (b), a polymerization reaction is carried out using a polymerization-initiator. The polymerization can be performed by a polymerization reaction in a solvent or a bulk polymerization process. The polymerization reaction in a solvent may be performed either by a batch operation or a continuous operation and, a preferable solvent using in this reaction is water; a lower alcohol such as methanol, ethanol, isopropanol and the like; an aromatic hydrocarbon such as benzene, toluene, xylene and the like; an alicyclic hydrocarbon such as cyclohexane and the like; an aliphatic hydrocarbon such as n-hexane and the like; ethyl acetate; a ketone such as acetone, methyl ethyl ketone and the like; dimethylformamide; and 1,4-dioxane and the like. When the polymerization reaction is performed in a water medium, a water-soluble polymerization-initiator such as ammonium persulfate and an alkali metal persulfate and hydrogen peroxide and the like is used. In this case, an accelerator such as sodium hydrogen sulfite and the like may be jointly used. On the other hand, in a polymerization reaction in which an organic solvent is used, there is used as an polymerization-initiator a peroxide such as benzoyl peroxide, lauroyl peroxide and the like; a hydroperoxide such as cumene hydroperoxide and the like; and an aliphatic azo compound such as azobis(isobutyronitrile) and the like. In this case, an accelerator such as an amine compound and the like may be jointly used. In a case where a mixture solvent of water and a lower alcohol is used, proper selection from the above-described various kinds of polymerization initiators and from combination of polymerization-initiators with accelerators is carried out for use. A polymerization temperature is properly set according to an using solvent and a polymerization-initiator and, in an usual case, it is in a range of from 0° to 120° C. The bulk polymerization reaction is carried out by using a polymerization-initiator such as used in the forementioned polymerization reaction in an organic solvent and in a temperature range of from 50° to 150° C. The polymerization may be carried out in the presence of a molecular weight regulator such as thioglycolic acid, mercaptoethanol, butanethiol and the like. A hydrophilic crosslinked polymer of this invention is obtained by a reaction of the formed water-soluble oligomer (A) with the compound (B). It is required to use the compound (B) in an amount so that a mole ratio between the functional group (IV) which B has, and the functional group (IV-A) having reactivity with the functional group (IV) of the compound (B) among the functional groups which A has, is satisfactory for the following equation; ##EQU2## Here, the functional group (IV-A) which A has is at least one of the functional group (I) and a functional group other than I. In a case where the compound (B) has not the group (II) or (III) as a composition unit, at least one of the groups (II) and (III) must be formed as a composition unit by a reaction of the functional group (IV-A) with the group (IV) which B has. If it is not so, that is, in a case where the compound (B) has at least one of the groups (II) and (III) as a composition unit, a composition unit other than the group (II) or (III) may be formed by a reaction of the functional group (IV-A) with the group (IV) which B has. A functional group other than the group (I) may be at least one kind of an amino group, a hydroxyl group, sulfonic acid group and the like, but it is not limited with these. The functional group (I) originates from the monomer (a) that is a monomer component, and a functional group other than I originates from the monomer (b). If the ratio of compound (B) is below the forementioned range, the water-soluble oligomer not crosslinked remains a lot and, if the ratio exceeds the range, the dispersing effect of an obtained crosslinked polymer is not unsatisfactory. A process of undergoing a reaction of the water-soluble oligomer (A) with the compound (B) is not especially limited and, for example, it is carried out in an aqueous solution, an organic solvent, or in a condition of no solvent. The reaction temperature is not especially limited as far as it is a temperature at which the reaction of the water-soluble oligomer (A) with the compound (B) proceeds, but a preferable temperature is in a range of from 50° to 200° C. In case of necessity, a catalyst may be used. To carry out the crosslinking reaction in a water system is preferred from viewpoints of resource saving, environmental problems and safety. More preferable is to subject a water-soluble oligomer and a substance reactive with this oligomer to thermal treatment at a temperature of 50° to 200° C. and to carry out a crosslinking reaction eliminating water. A preferable device for this treatment is a common drier for producing powder such as a drum drier, belt conveyor type hot air drier, belt conveyor type heat-conducting drier and the like. In this case, it is preferred to carry out reaction in a slurry condition and, by repeating drying and water-adding, a hydrophilic crosslinked polymer having a higher molecular weight can be obtained. The monomer (a) used in this invention is a monoethylenic unsaturated carboxylic acid having a carbon number of 3 to 6 and its salt and, for example, acrylic acid, methacrylic acid, 2-chloroacrylic acid, crotonic acid, maleic acid, fumaric acid, itaconic acid, citraconic acid, aconitic acid and salts of these acids (for example, a monovalent metal salt, divalent metal salt, trivalent metal salt, an ammonium salt and organic amine salt). In this invention, one kind or two kinds or more of these acids and salts can be used. Among these acids and salts, especially preferable ones are acrylic acid, methacrylic acid and maleic acid as well as a monovalent metal salt, divalent metal salt, trivalent metal salt, an ammonium salt and organic amine salt of these three acids. The monomer (b) used in this invention is another type monoethylenic unsaturated monomer capable of copolymerizing with the monomer (a) and, for example, various kinds of compounds are used in a range that the water-soluble oligomer (A) being made by copolymerizing with the monomer (a) is soluble in water. Preferable examples of the monomer (b) are, for example, α-olefins having a carbon number of 2 to 8 such as ethylene, propylene, isobutylene, m-butylene, isoamylene, diisobutylene and the like; alkyl esters of acrylic acid and methacrylic acid having a carbon number of 4 to 8 such as methyl (meth)acrylate, ethyl (meth)acrylate, isopropyl (meth)acrylate, n-propyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate and the like; hydroxyalkyl esters of acrylic acid and methacrylic acid having a carbon number of 5 to 8 such as hydroxyethyl (meth)acrylate, hydroxy-n-propyl (meth)acrylate, hydroxyisopropyl (meth)acrylate, hydroxy-n-butyl (meth)acrylate, hydroxy-isobutyl (meth)acrylate and the like; polyether mono(meth)acrylates having a carbon number of 6 to 104 such as polyethylene glycol mono(meth)acrylate, polypropylene glycol mono(meth)acrylate, polyethylene glycol polypropylene glycol mono(meth)acrylate and the like; sulfoalkyl (meth)acrylates having a carbon number of 4 to 10 such as 2-sulfoethyl (meth)acrylate, 2-sulfopropyl (meth)acrylate, 3-sulfopropyl (meth)acrylate, 1-sulfopropan-2-yl (meth)acrylate, 2-sulfobutyl (meth)acrylate, 3-sulfobutyl (meth)acrylate, 4-sulfobutyl (meth)acrylate, 1-sulfobutan-2-yl (meth)acrylate, 1-sulfobutan-3-yl (meth)acrylate, 2-sulfobutan-3-yl (meth)acrylate, 2-methyl-2-sulfopropyl (meth)acrylate, 1,1-dimethyl-2-sulfoethyl (meth)acrylate and the like; sulfoalkoxypolyalkylene glycol mono(meth)acrylates having a carbon number of 7 to 97 such as sulfoethoxypolyethylene glycol mono(meth)acrylate, sulfopropoxypolyethylene glycol mono(meth)acrylate, sulfobutoxypolyethylene glycol mono(meth)acrylate, sulfoethoxypolypropylene glycol mono(meth)acrylate, sulfopropoxypolypropylene glycol mono(meth)acrylate, sulfobutoxypolypropylene glycol mono(meth)acrylate and the like as well as monovalent metal salts, divalent metal salts, trivalent metal salts, an ammonium salts and organic amine salts of the above-described glycol mono(meth)acrylates; polyalkylene glycol mono(meth)allyl ethers having a carbon number of 5 to 104 such as polyethylene glycol monoallyl ether, polypropylene glycol monoallyl ether, polyethylene glycol polypropylene glycol monoallyl ether, polyethylene glycol monomethallyl ether, polypropylene glycol monomethallyl ether, polyethylene glycol polypropylene glycol monomethallyl ether and the like; alkenyl acetates having a carbon number of 4 to 7 such as vinyl acetate, propenyl acetate and the like (the alkenyl acetates, after polymerization, can be converted into vinyl alcohols by hydrolysis in part or wholly); aromatic vinyl compounds having a carbon number of 8 to 10 such as styrene, p-methylstyrene and the like; aminoethyl (meth)acrylates having a carbon number of 5 to 10 such as dimethylaminoethyl (meth)acrylate, diethylaminoethyl (meth)acrylate and the like; (meth)acrylamides having a carbon number of 3 to 12 such as (meth)acrylamide, dimethylaminopropyl(meth)acrylamide, diethylaminopropyl(meth)acrylamide and the like; monoethylenic unsaturated sulfonic acids having a carbon number of 2 to 4 such as 2-acrylamido-2-methylsulfonic acid, vinylsulfonic acid, allylsulfonic acid and the like; monoethylenic unsaturated phosphonic acids having a carbon number of 2 to 4 such as vinylphosphonic acid, allylphosphonic acid and the like; and (meth)acrylonitrile, acrolein, (meth)allyl alcohol, isoprenol and the like. All the compounds can be used alone or in combination of two or more kinds. In the above-described late crosslinking process, to use the following maleic acid-based polymer as the water-soluble oligomer (A) is preferred to elevate biodegradability of the hydrophilic crosslinked polymer of this invention. The maleic acid-based polymer is made by polymerizing in an aqueous solution a monomer component, which is composed of 50 to 100 mole % of the monomer (a) and of a residue mole % of the monomer (b); wherein a 20 to 100% by weight part of the monomer component (a+b) is at least one kind selected from maleic acid and its salt as the monomer (a), and a residual % part of the monomer component (a+b) is the monomer (a) excepting the maleic acid and its salt plus water-soluble ones of the monomer (b). This polymerization reaction in an aqueous solution is carried out in the presence of a metal ion of at least one or a plural kind selected from a group consisting of an iron ion, an vanadium atom containing ion and a copper ion in a weight ratio of from 0.5 to 300 ppm to said monomer component and using hydrogen peroxide as a polymerization catalyst in the proportion of 8 to 500 g per 1 mole of said monomer component. Preferable examples of a vanadium atom containing ion, an iron ion and a copper ion in this invention are, for example, V 2+ , V 3+ , VO 2+ , VO 3 2- , Fe 3+ , Fe 2+ , Cu 2+ and the like and, among those, VO 2+ , Fe 3+ and Cu 2+ are especially preferable. In order to elevate a polymerization character, VO 2+ is especially preferred. The condition for supplying these polyvalent metal ions into a polymerization system has no special limitation and, a polyvalent metal compound or a metal simple substance can be used as far as it undergoes ionization in a polymerization system. The compound (B) used in this invention has at least two of the functional group (IV) capable of reacting with the functional group which the water-soluble oligomer (A) or the maleic acid-based polymer has, and also, it is a compound having at least one of the forementioned groups (II) and (III) as a composition unit between said functional groups (IV) or a compound forming at least one of the groups (II) and (III) by a reaction of the functional group (IV) with the functional group which A or the maleic acid-based polymer has. Here, preferable examples of the functional group (IV) are, for example, a hydroxyl group, an amino group, epoxy group, isocyanate group and the like, and one kind or two kinds or more in combination among these groups are used. Practical examples of the compound (B) are, for example, polyhydric alcohols such as ethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, glycerin, polyglycerin, propylene glycol, polyoxypropylene, an oxyethylene-oxypropylene block copolymer, diethanolamine, triethanolamine, pentaerythritol, sorbitol, a sorbitane fatty acid ester, hydroxyacetic acid glycol monoester, lactic acid glycol monoester, hydroxypivalic acid neopentylene glycol ester, polyvinylalcol, a partially saponified product of polyvinyl acetate and the like; lactone polymers having hydroxyl groups at both terminal ends such as a poly-ε-caprolactone having hydroxyl groups at both the terminal ends and the like; polyglycidyl compounds such as ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, glycerol polyglycidyl ether, diglycerol polyglycidyl ether, polyglycerol polyglycidyl ether, sorbitol polyglycidyl ether, pentaerythritol polyglycidyl ether, propylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, resorcinol diglycidyl ether, 1,6-hexanediol diglycidyl ether, adipinic acid diglycidyl ester, o-phthalic acid diglycidyl ester, terephthalic acid diglycidyl ester, p-hydroxybennzoic acid glycidyl ester ether and the like; polyamine such as ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, polyethyleneimine, phenylenediamine and the like, polyaziridine such as 2,2-bish ydroxymethylbutanol-tris[3-(1-aziridinyl)propionate], 1,6-hexamethylenediethyleneurea, diphenylmethane-bis-4,4'-N,N'-diethyleneurea and the like; polyaldehyde such as glutaraldehyde, glyoxal and the like; and polyisocyanate such as tolylene 2,4-diisoccyanate, hexameth ylenediisocyanate and the like; compounds having both a carboxyl group and a hydroxyl group such as tartaric acid, citric acid, malic acid, lactic acid and the like; imino acids such as 2,2'-iminodisuccinic acid, 3-hydroxy-2,2'-iminodisuccinic acid and the like; and amino acids such as aspartic acid, β-alanine and the like. The compounds are used alone or in combination of two or more kinds. In a case where at least one composition unit of the groups (II) and (III) is formed by a reaction of the water-soluble oligomers (A) one another, a part of the water-soluble oligomer (A) can be made to the compound (B). That is, the compound (B) in this case is the same as the water-soluble oligomer (A). The hydrophilic crosslinked polymer of this invention is superior in chelating and dispersing effects, shows hydrophilicity (preferably, a water-soluble character) and excellent biodegradability. Because of this, the hydrophilic crosslinked polymer of this invention can be used as a builder of a cleaner. The builder of this invention consists of the hydrophilic crosslinked polymer of this invention and, by combining with a detergent composition, the detergency of this composition is elevated. The detergent composition of this invention contains a surfactant agent and the builder of this invention as essential components, and it can be used for a detergent in any condition of a powder, solid and liquid. Preferable surfactants are an anionic surfactant, a nonionic surfactant, an ampholytic surfactant and a cationic surfactant, and these surfactants are used alone or in combination of two or more kinds. The surfactant and the builder of this invention are used, for example, in a proportion of 0.5 to 100 parts by weight of the builder to 100 parts by weight of the surfactant, but it is not limited with the proportion. If the builder exceeds the proportion range, an economical disadvantage occurs and, if it is less, a merit by adding this builder is not practically expected. The builder of this invention can be used by combining it with a conventional builder, for example, a condensed phosphate, zeolite, citrate and the like. In this case, the proportion for use is properly set and not especially limited. Furthermore, in addition to the surfactant and builder, other ingredients which are conventionally used for a detergent composition may be combined with the detergent composition of this invention. Examples of the other ingredients are, for example, an alkali agent, inorganic electrolyte, a chelating agent, an agent to prevent recontamination, enzyme, a bleach, fluorescent agent, an antioxidant, a solubilizer, colorant, perfume and the like. An amount to be combined is, for example, an usual amount. The fiber-treating agent of this invention can be used for a purpose such as dispersion or removal of paste remaining on fiber, metal salt, metal oxide, and other pollutants in a process of scouring, dyeing, bleaching, soaping and the like. An applicable fiber is not especially limited, but preferable ones are, for example, cellulose-based fibers such as Nylon, a polyester and the like; animal fibers such as wool and silk ane the like; semisynthetic fibers such as rayon and the like; and textiles and mixed fabrics of these fibers. The fiber-treating agent may consist of only the hydrophilic crosslinked polymer of this invention, but in the case of application for a scouring process, it is preferred to combine an alkali agent and a surface-active agent with the hydrophilic crosslinked polymer of this invention, and in the case of application for a bleaching process, it is preferred to combine silicic acid-based chemicals such as sodium silicate and the like as a decomposition suppresant of an alkali-based bleaching agent with the hydrophilic crosslinked polymer of this invention. The inorganic pigment dispersant of this invention displays excellent performance as a dispersant of the inorganic pigment, which is, for example, a light type or heavy type of calcium carbonate using for paper-coating, clay and the like. The inorganic pigment dispersant of this invention may consist of only the hydrophilic crosslinked polymer of this invention, but polyphosphoric acid and its salt, phosphonic acid and its salt, polyvinyl alcohol and the like may be used as other kinds of combining agents in a range of not disturbing the effects of this invention. By adding a small amount of the inorganic pigment dispersant of this invention, instead of a conventional inorganic pigment dispersant, into such an inorganic pigment as described above (for example, in a ratio of 0.05 to 2.0 parts by weight to 100 parts by weight of an inorganic pigment) and, thereby, by dispersing the inorganic pigment into water, there can be produced inorganic pigment slurry of a high concentration, which shows low viscosity and high fluidity as well as excellence in stability with the passage of time of these performance (for example, calcium carbonate slurry of high concentration). Since the hydrophilic crosslinked polymer of this invention is excellent in biodegradability, an influence on environment can be minimized, when a paper comprising application of the inorganic pigment dispersant of this invention is dumped into ground as garbage. The water treatment agent of this invention is useful for scale inhibitor in a cooling water system, a boiler water system, a desalination plant, a pulp digestor, a black liquor evaporator and the like, and although it may be used alone as a water treatment agent, conversion into a composition combined with an anticorrosive such as a polyphosphate, a phosphonate and others, or with a slime-controlling agent, a chelating agent or the like is possible. Concerning the water treatment agent of this invention, even if discharged water containing the hydrophilic crosslinked polymer comes to the outside after use, because the biodegradability is excellent, the influence on environment is very little. The hydrophilic crosslinked polymer of this invention is easy in biodegradation at the parts of the groups (II) and (III) and, with this biodegradation, a water-soluble oligomer containing an ingredient of molecular weight 5,000 or less in 50% by weight or more is formed. A water-soluble oligomer of this type has a molecular weight too small to display the chelating and dispersing effects, but biodegradation of this is possible. That is, although the hydrophilic crosslinked polymer of this invention has a molecular weight too small to display the chelating and dispersing effects, its molecular weight increases up to such magnitude that the chelating and dispersing effects emerge, by combining one another of the main chains having a water-soluble oligomer structure of a molecular weight of biodegradable magnitude through a biodegradable group. Accordingly, compatibility of the biodegradability with the chelating and dispersing effects became possible. According to the forementioned late crosslinking process, since the water-soluble oligomers are crosslinked one another after they were once formed, the molecular weight of main chains are easy to set at proper magnitude. Since the builder of this invention consists of the above-described hydrophilic crosslinked polymer, dispersion into water is excellent and biodegradability is superior, and thence, detergency of a detergent can be enhanced. Since the fiber-treating agent, inorganic pigment dispersant and water treatment agent of this invention consist of comprising the hydrophilic crosslinked polymer of this invention as explained above, they are excellent in the dispersing and chelating performance and the biodegradability, and very useful for various kinds of use. DESCRIPTION OF THE PREFERRED EMBODIMENTS EXAMPLE The present invention is illustrated by the following Examples of some preferred embodiments in comparison with Comparative Examples not according to the invention. However, the invention is not limited with the Examples. Hereinafter, the "part" denotes "part by weight". EXAMPLE 1 Into a glass-made reaction vessel equipped with a thermometer, stirrer, distilling receiver and reflux condenser were placed and dissolved 45.6 parts of dimethylformamide, 28.8 parts of polyacrylic acid which contains an ingredient of molecular weight 300 to 2,500 in 68% by weight and an ingredient having a molecular weight in a range of from over 2,500 to 5,000 or less in 11% by weight, that in turn contains an ingredient of molecular weight 300 to 5,000 in 79% by weight. To the obtained mixture solution were added with stirring 4 parts of ethylene glycol and 0.3 parts of 95% sulfuric acid, and the thus-obtained mixture was heated up to 150° C. Eliminating distilled water from the distilling receiver, the reaction mixture was still maintained for 5 hours to complete reaction and then, cooled to ordinary temperature, diluted with 150 parts of water, and completely neutralized with a 10% aqueous sodium hydroxide solution. After neutralization, the reaction mixture was separated to two phases. The water phase was taken out and added into a large amount of methanol. A precipitate thus-formed was taken by filtration and dried at 60° C. under a reduced pressure, whereby 39 parts of a hydrophilic crosslinked polymer was obtained. By adding water to the obtained hydrophilic crosslinked polymer, a 20% by weight aqueous solution was prepared and measured at 20° C. by using a B type rotatory viscosimeter VISMETRON VG-A/1 model (made by Seiki kogyo kenkyusho) and a viscosity of 73 cP was found. A 10% by weight aqueous solution of the hydrophilic crosslinked polymer was prepared and, to this solution, a 48% by weight aqueous sodium hydroxide solution was added to adjust pH at 14, and the obtained solution was heated at reflux temperature for 4 hours for degradation. The degradated product was treated with gel permeation chromatography and the result indicated that molecular weight distribution of the polyacrylic acid part was the same as that of the precrosslinking polyacrylic acid. The conditions of gel permeation chromatography was as follows. Column: SHODEX OHpak KB-806, 804, 802.5, 802, 800P (made by Showa Denko Co., Ltd.). Eluent: a 0.2M potassium dihydrogen phosphate solution, which was adjusted at pH 6.9 by sodium hydroxide. Eluent volume: 0.5 ml per minute. Detector: a differential refractive index detector (Shodex RI SE-61, a product trade name of Showa Denko Co., Ltd.). EXAMPLE 2 Into a glass-made reaction vessel equipped with a thermometer, stirrer, distilling receiver and reflux condenser were placed and dissolved 45.6 parts of dimethylformamide, 33.1 parts of polyacrylic acid which contains an ingredient of molecular weight 300 to 2,500 in 36% by weight and an ingredient having a molecular weight of from over 2,500 to 5,000 or less in 28% by weight, that in turn contains an ingredient of molecular weight 300 to 5,000 in 64% by weight, and to the obtained mixture solution were added with stirring 1 part of ethylene glycol and 0.37 parts of 95% sulfuric acid, and the thus-obtained mixture was heated up to 150° C. Eliminating distilled water from the water measuring tube, the reaction mixture was still maintained for 5 hours to complete reaction and then, cooled to ordinary temperature, diluted with 200 parts of water, and completely neutralized with a 10% aqueous sodium hydroxide solution. After neutralization, the reaction mixture was separated to two phases. The water phase was taken out and added into a large amount of methanol. A precipitate thus-formed was taken by filtration and dried at 60° C. under a reduced pressure, whereby 43 parts of a hydrophilic crosslinked polymer was obtained. The viscosity determined for this hydrophilic crosslinked polymer similarly to the case of Example 1 was 150 cP. Molecular weight distribution of the polyacrylic acid part was the same as that of the precrosslinking polyacrylic acid, which was measured after degradation similarly to the case of Example 1. EXAMPLE 3 Into a glass-made reaction vessel equipped with a thermometer, stirrer, distilling receiver and reflux condenser were placed and dissolved 35.3 parts of dimethylformamide, 25.6 parts of polyacrylic acid which contains an ingredient of molecular weight 300 to 2,500 in 46% by weight and an ingredient having a molecular weight of from over 2,500 to 5,000 or less in 29% by weight, that in turn contains an ingredient of molecular weight 300 to 5,000 in 75% by weight. To the obtained mixture solution were added with stirring 3.88 parts of polyethylene glycol having an average molecular weight of 300 and 0.29 parts of 95% sulfuric acid, and the thus-obtained mixture was heated up to 142° C. Eliminating distilled water from the water measuring tube, the reaction mixture was still maintained for 4 hours to complete reaction and then, cooled to ordinary temperature, diluted with 200 parts of water, and completely neutralized with a 10% aqueous sodium hydroxide solution. After neutralization, the reaction mixture was separated to two phases. The water phase was taken out and added into a large amount of methanol. A precipitate thus-formed was taken by filtration and dried at 60° C. under a reduced pressure, whereby 36 parts of a hydrophilic crosslinked polymer was obtained. The viscosity determined for this hydrophilic crosslinked polymer similarly to the case of Example 1 was 85 cP. Molecular weight distribution of the polyacrylic acid part was the same as that of the precrosslinking polyacrylic acid, which was measured after degradation similarly to the case of Example 1. EXAMPLE 4 Into a glass-made reaction vessel equipped with a thermometer, stirrer, distilling receiver and reflux condenser were placed and dissolved 86.4 parts of dimethylformamide, 26.8 parts of polyacrylic acid which contains an ingredient of molecular weight 300 to 2,500 in 46% by weight and an ingredient having a molecular weight of from over 2,500 to 5,000 or less in 29% by weight, that in turn contains an ingredient of molecular weight 300 to 5,000 in 75% by weight. With stirring, 2.11 parts of tetraethylenepentamine was added to the above mixture, which was then warmed to 140° C. Eliminating distilled water from the water measuring tube, the reaction mixture was still maintained for 7 hours to complete reaction and then, cooled to ordinary temperature, diluted with 200 parts of water, and completely neutralized with a 10% aqueous sodium hydroxide solution. After neutralization, the reaction mixture was separated to two phases. The water phase was taken out and added into a large amount of methanol. A precipitate thus-formed was taken by filtration and dried at 60° C. under a reduced pressure, whereby 35 parts of a hydrophilic crosslinked polymer was obtained. The viscosity determined for this hydrophilic crosslinked polymer similarly to the case of Example 1 was 92 cP. Molecular weight distribution of the polyacrylic acid part was the same as that of the precrosslinking polyacrylic acid, which was measured after degradation similarly to the case of Example 1. EXAMPLE 5 Into a glass-made reaction vessel equipped with a thermometer, stirrer and reflux condenser were placed and dissolved 37.6 parts of dimethylformamide, 27.2 parts of polyacrylic acid which contains an ingredient of molecular weight 300 to 2,500 in 46% by weight and an ingredient having a molecular weight of from over 2,500 to 5,000 or less in 29% by weight, that in turn contains an ingredient of molecular weight 300 to 5,000 in 75% by weight. With stirring, 1.93 parts of terephthalic acid diglycidyl ester ("DENACOL EX-711", a product trade name by Nagase Kasei Co., Ltd.) was added to the above mixture, which was then warmed to 105° C. The mixture was maintained for 4 hours under these conditions to complete reaction and then, cooled to ordinary temperature, diluted with 200 parts of water, and completely neutralized with a 10% aqueous sodium hydroxide solution. After neutralization, the reaction mixture was separated to two phases. The water phase was taken out and added into 1,000 parts of methanol. A precipitate thus-formed was taken by filtration and dried at 60° C. under a reduced pressure, whereby 33 parts of a hydrophilic crosslinked polymer was obtained. The viscosity determined for this hydrophilic crosslinked polymer similarly to the case of Example 1 was 82 cP. Molecular weight distribution of the polyacrylic acid part was the same as that of the precrosslinking polyacrylic acid. EXAMPLE 6 Into a glass-made reaction vessel equipped with a thermometer, stirrer and reflux condenser were placed and dissolved 84 parts of water and 21 parts of a sodium acrylate-vinyl alcohol copolymer; which contains an ingredient of molecular weight 300 to 2,500 in 52% by weight and an ingredient having a molecular weight of from over 2,500 to 5,000 or less in 20% by weight, that in turn contains an ingredient of molecular weight 300 to 5,000 in 72% by weight; and wherein the mole ratio of sodium acrylate to vinyl alcohol was 8 to 2. With stirring, 1.2 parts of adipinic acid diglycidyl ester ("DENACOL EX-701", a product trade name by Nagase Kasei Co., Ltd.) was added to the above mixture, which was then warmed to 95° C. The mixture was maintained for 4 hours under these conditions to complete reaction and then, cooled to room temperature, and poured into 1,000 parts of methanol. A precipitate thus-formed was taken by filtration and dried at 60° C. under a reduced pressure, whereby 24 parts of a hydrophilic crosslinked polymer was obtained. The viscosity determined for this hydrophilic crosslinked polymer similarly to the case of example 1 was 80 cP. Molecular weight distribution of the acrylic acid-vinyl alcohol copolymer part was the same as that of the precrosslinking sodium acrylate-vinyl alcohol copolymer. EXAMPLE 7 Into a glass-made reaction vessel equipped with a thermometer, distilling receiver, stirrer and reflux condenser were placed and dissolved 76 parts of water and 20 parts of an acrylic acid-maleic acid copolymer; which contains an ingredient of molecular weight 300 to 2,500 in 41% by weight and an ingredient having a molecular weight of from over 2,500 to 5,000 or less in 27% by weight, that in turn contains an ingredient of molecular weight 300 to 5,000 in 68% by weight; and wherein the mole ratio of acrylic acid to maleic acid was 7 to 3. With stirring, 1.8 parts of adipinic acid diglycidyl ester ("DENACOL EX-701", a product trade name by Nagase Kasei Co., Ltd.) was added to the above mixture, which was then warmed to 95° C. The mixture was maintained for 5 hours under these conditions to complete reaction and then, cooled to room temperature, completely neutralized with an aqueous sodium hydroxide solution, and poured into 2,000 parts of methanol. A precipitate thus-formed was taken by filtration and dried at 60° C. under a reduced pressure, whereby 21 parts of a hydrophilic crosslinked polymer was obtained. The viscosity determined for this hydrophilic crosslinked polymer similarly to the case of example 1 was 320 cP. Molecular weight distribution of the acrylic acid-maleic acid copolymer part was the same as that of the precrosslinking acrylic acid-maleic acid copolymer. COMPARATIVE EXAMPLE 1 The polyacrylic acid, which was used in the example 1 and contained an ingredient of molecular weight 300 to 2,500 in 68% by weight and an ingredient having a molecular weight of from over 2,500 to 5,000 or less in 11% by weight, that in turn contained an ingredient of molecular weight 300 to 5,000 in 79% by weight, was converted into its sodium salt without crosslinking treatment and then, subjected to the following tests. COMPARATIVE EXAMPLE 2 Sodium polyacrylate, which contained an ingredient of molecular weight 300 to 2,500 in 1% by weight and an ingredient having a molecular weight of from over 2,500 to 5,000 or less in 5% by weight and an ingredient of molecular weight 5,000 to 50,000 in 65% by weight, that in turn contained an ingredient of molecular weight 300 to 5,000 in 6% by weight, was not crosslinked and, without any treatment, subjected to the following tests. Concerning the hydrophilic crosslinked polymers obtained from the above-described examples and the polymers obtained from the comparative examples, the content of functional group (I), whether or not the bonds formed between main chains of the polymers have the group (II) or (III), biodegradability, the chelating and dispersing effects were examined according to the following procedure. The content of functional group (I) was determined by taking an aqueous solution or a dispersed-in-water solution of the polymer, neutralizing this solution by titrating with a 0.1N aqueous sodium hydroxide solution using an automatic titration apparatus GT-01 model (made by Mitsubishi Kasei Kogyo Co., Ltd.), and counting an amount of the sodium hydroxide solution required for neutralization, and it was indicated by a mole number being contained in 1 g of the polymer. Whether or not the bonds formed between main chains of the polymers have the group (II) or (III) was examined by the presence or absence of ester or amide absorption bands on the infrared absorption spectra. The biodegradability was examined by adding activated sludge into a culture medium solution having the composition shown in Table 1, carrying out shaking culture at 30° C. for 30 days, treating with gel permeation chromatography, and looking at variation of the peak shape before and after the culture (decreasing percentage of the peak area), and the results were evaluated according to the following standards. ⊚: decrease of the peak area was 50% or more. ◯: decrease of the peak ares was in a range of from 10% up to 50%. Δ: decrease of the peak ares was less than 10%. X: almost no change of the peak area. TABLE 1______________________________________Composition of culture medium solution______________________________________crosslinked polymer or polymer 1 gammonium sulfate 1 gpotassium dihydrogen phosphate 0.5 gdipotassium hydrogen phosphate 0.5 gmagnesium sulfate 0.2 gsodium chloride 0.1 gyeast extract 0.1 gcalcium sulfate 2 mgferrous sulfate 2 mgmanganese sulfate 2 mgzinc sulfate 7 mgdistilled water 1000 ml______________________________________ The chelating effect was measured by taking 10 mg of a crosslinked polymer or a polymer as a sample into a 50 ml beaker, dissolving the sample in 50 ml of an aqueous solution which was prepared so as to have calcium chloride at a concentration of 1.0×10 -3 M and potassium chloride at a concentration of 0.08M, stirring the sample solution, determining the calcium ion concentration in the solution using a divalent cation electrode (MOdel 93-32, made by Orion Research Incorporated) and an ion analyzer (Model EA 920, made by Orion Research Incorporated), and converting an amount of the calcium ion chelated by 1 g of the crosslinked polymer or the polymer into mg of calcium carbonate. The dispersion effect was measured by preparing a slurry so as to have a 60:40 weight ratio of calcium carbonate (BRILLIANT 1500, a product trade name by Shiraishi Kyokgo Co., Ltd.) to water, adding into the slurry a crosslinked polymer or a polymer in 0.3% by weight of the calcium carbonate content in the slurry, then stirring for 3 minutes, and after standing the polymer-slurry mixture for 1 minute, measuring viscosity by a B type rotatory viscosimeter VISMETRON VG-A/1 model (made by Seiki Kyogyo Kenkyusho) to show the viscosity by a centipoise unit. Besides, when the crosslinked polymer or the polymer is not added, the slurry has almost no fluidity and the viscosity measurement was impossible. Results thus-obtained are shown in Table 2. TABLE 2__________________________________________________________________________ Comparative Example example 1 2 3 4 5 6 7 1 2__________________________________________________________________________Viscosity of polymer 73 150 85 92 82 80 320 5 80at 20° C. (cp)Amount of functional 6.3 7.2 7.3 6.2 7.6 7.4 7.3 9.8 10.2group (I) (mmol/g)Whether or not the bonds yes yes yes yes yes yes yes no noformed between main chainshave the group (II) or (III)Biodegradability ⊚ Δ ◯ ◯ ◯ ⊚ ◯ ⊚ XChelating effect 150 167 171 141 180 185 178 80 236(mg-CaCO.sub.3 /g)Dispersing effect (cp) 1000 320 700 900 370 850 1800 9000 400__________________________________________________________________________ As seen in Table 2, the crosslinked polymers of the examples were satisfactory for all the biodegradability and chelating and dispersing effects. In contrast, those of the comparative examples were satisfactory for the biodegradability, but not for the chelating and dispersing effects. Otherwise, those were satisfactory for the chelating and dispersing effects, but not satisfactory for the biodegradability. EXAMPLES 8 TO 14 AND COMPARATIVE EXAMPLES 3 AND 4 Using the crosslinked polymers of examples 1 to 7 and the compounds of comparative examples 1 and 2 as builders, detergent compositions were obtained with the following formulation. ______________________________________Sodium alkylbenzenesulfonate 25 partsBuilder 20 partsSodium silicate 5 partsAnhydrous sodium carbonate 3 partsCarboxymethylcellulose 0.5 partsAnhydrous sodium sulfate 40 partsWater residueTotal of detergent composition 100 parts______________________________________ Detergency of the detergent compositions obtained from the examples and comparative examples were examined and results are shown in Table 3. The detergency was tested by using each of the crosslinked polymers of the examples and the compounds of the comparative examples as a sample builder, preparing a detergent solution by dissolving the detergent composition obtained with the above-described formulation in tap water of hardness 3° DH (Japanese hardness) so as to have a 0.2% by weight concentration, immersing an artificially contaminated cotton cloth in a detergent solution of 25° C. (bath ratio: 30 times), and performing washing for 10 minutes at 100 rpm using a detergent device (Terg-O-Tometer, made by Ueshima Seisakusho) and then, performing rinsing for 5 minutes with tap water of 3° DH at 25° C. using the same device, and wind-drying. Contamination-free condition of the cloth treated by the washing and rinsing were evaluated by taking the compound of comparative example 2 as a standard builder and seeing by a naked eye in comparison with the standard, and the evaluation was given by the following standards. ⊚: excellent ◯: almost the same Δ: somewhat inferior X: considerably inferior TABLE 3______________________________________ Builder Detergency______________________________________Example 8 Example 1 ◯Example 9 Example 2 ◯Example 10 Example 3 ◯Example 11 Example 4 ◯Example 12 Example 5 ⊚Example 13 Example 6 ◯Example 14 Example 7 ◯Comparative example 3 Comparative example 1 XComparative example 4 Comparative example 2 --______________________________________ As seen in Table 3, the crosslinked polymers of the examples showed excellent detergency compared with the compounds of the comparative examples. Synthetic Example 1 Into a four-necked flask equipped with a thermometer, stirrer and reflux condenser were charged 196 parts of maleic anhydride (232 parts as maleic acid), 140 parts of deionized water and 0.0412 parts of iron (III) ammonium sulfate 12 hydrate (20 ppm as Fe 3+ in 1 part of the charged monomer component) and, by stirring this mixture, an aqueous solution was made, which was warmed up to the boiling temperature under ordinary pressure. Then, into this aqueous solution was added dropwise and continuously 777 parts of 35% aqueous hydrogen peroxide (in a ratio of 136 g of H 2 O 2 per 1 mole of the charged monomer component) during 5 hours to complete a polymerization reaction, whereby an aqueous solution of the water-soluble oligomer (1) (solid portion was 21%) was obtained. An acid value per the solid portion of this water-soluble oligomer (1) was determined by titration and then, a number of the carboxylic acid unit (an average value) per one molecule of the water-soluble oligomer and a content of the functional group (I) were obtained by calculation. Results are shown in Table 4. Synthetic Example 2 The polymerization procedure of synthetic example 1 was repeated except that, after the same materials as those in the synthetic example 1 were charged, 777 parts of 35% aqueous hydrogen peroxide and 180.25 parts of a 80% aqueous acrylic acid solution were added dropwise and continuously during 5 hours from respectively different dropping inlets to complete polymerization, whereby an aqueous solution of the water-soluble oligomer (2) (solid portion was 27%) was obtained. Analysis of this aqueous solution of water-soluble oligomer (2) was performed similarly to the case of the synthetic example 1 and results obtained are shown in Table 4. TABLE 4______________________________________ Synthetic ExampleProperties of obtained water-soluble oligomer 1 2______________________________________Numbering of aqueous solution of (1) (2)water-soluble oligomerCharacterMolecular weight 400 500Acid value (mgKOH/g) 850 600Content of functional group (I) (mmol/g) 15.2 10.7Number of carboxylic acid unit per molecule 4.5 5.4(average value) (piece)Percentage of an ingredient of molecular weight 70 8030 to 2500 (%)______________________________________ EXAMPLE 15 In a glass-made plate were placed 100 parts of the aqueous solution of water-soluble oligomer (1) obtained from the synthetic example 1, 50 parts of citric acid and 2 parts of 48% aqueous sodium hydroxide and, the mixture was made homogeneous with stirring and treated by heating eliminating water by blowing hot air at 150° C. for 2 hours, whereby the hydrophilic crosslinked polymer (15) was obtained. The molecular weight of obtained hydrophilic crosslinked polymer (15) was determined by gel permeation chromatography under the above-described conditions and the acid value was obtained by titration. Concerning the hydrophilic crosslinked polymer (15), viscosity, whether or not the bond formed between main chains has the group (II) or (III), biodegradability, chelating and dispersing effects were investigated by the same measurements as those in the examples 1 to 7. Results from these measurements are shown in Table 5. In using the hydrophilic crosslinked polymer (15) as a fiber-treating agent and a water treatment agent, its performance was evaluated according to the undermentioned method. Results obtained are shown in Table 6. In using the hydrophilic crosslinked polymer (15) as an inorganic pigment dispersant, its performance was evaluated, in addition to evaluation of the dispersing effect, by investigating the viscosity stability which was determined by viscosity measured after standing for 1 week at room temperature. Results obtained are shown in Table 6. In using the hydrophilic crosslinked polymer (15) as a cleaner, its performance was evaluated similarly to the cases of examples 8 to 14. Results obtained are shown in Table 6. Evaluation in using the hydrophilic crosslinked polymer as a fiber-treating agent 1. Dyeing-improving capability and dye-dispersing performance (evaluation in using as a dyeing assistant) A cotton twill fabric was dyed under the following conditions. As a dyeing improver, the hydrophilic crosslinked polymer obtained from the example 15 was used in a proportion of 1 g (in an amount converted into a solid portion) to 1 liter of water. dyeing conditions Hardness of water used --30° DH (German hardness) Dye (Kayaras Supra Blue 4BL) --1% by weight (a metal-containing direct type dye, made by Nihon Kayaku Co., Ltd.) Sodium sulfate --10% by weight Bath ratio --1:30 Temperature --95° C. Time --30 minutes After dyeing, the color of a cloth was measured by a SM color computer SM-3 model, made by Suga Shikenki Co., Ltd., and a hue value (a value on a Munsell hue ring) was determined. In the hue value, PB means a blue purple color between purple and blue, and a blue purple color closer to the blue is shown by a smaller value, which indicates superior dyeing performance. Partial color unevenness was observed by seeing by a naked eye. Furthermore, 300 g of a mixed solution of water used in the above-described dyeing, a dye (0.1%) and a hydrophilic crosslinked polymer (0.1%) was prepared, stood for 24 hours, and filtered using a 5C filter paper made by Toyo Roshi Co., Ltd. Then, the dye-dispersing performance was evaluated by the standards; no residue on filtrating by ◯, some residue on filtrating by Δ, and a large amount of residue by X. 2. Bleaching performance and sewing performance (evaluation in using as a bleaching assistant) A scoured indian cotton woven knitting was bleached under the following conditions. As a bleaching assistant, the hydrophilic crosslinked polymer obtained from the example 15 was used in a proportion of 1 g (in an amount converted into a solid portion) to 1 liter of water. Bleaching conditions Hardness of water used--35° DH Bath ratio--1:25 Temperature--85° C. Time--30 minutes Chemicals used Hydrogen peroxide--10 g/liter sodium hydroxide--2 g/liter sodium silicate (No. 3)--5 g/liter After bleaching, the feeling of a cloth is determined by a sensory test method, and a soft feeling is indicated by ◯, a somewhat hard feeling by Δ, and a considerably hard feeling by X. The whiteness W is determined by subjecting to colorimetry by a SM color computer SM-3 model (made by Sugashikenki Co., Ltd.) followed by calculating those by the following Lab type whiteness equation. W=100-[(100-L).sup.2 +a.sup.2 +b.sup.2 ].sup.1/2 here, L=measured lightness a=measured chromaticity index b=measured chromaticity index Furthermore, bleached clothes were folded to four layers and sewed 30 cm with no string by a sewing machine using No. 11S needle, and then, sewing performance was evaluated by examining positions where thread was cut. Evaluation in using the hydrophilic crosslinked polymer as a water treatment agent 1. Scale-suppresive percentage In a glass bottle of 225 ml volume was placed 170 g of water and, with this water, were mixed 10 g of a 1.56% aqueous calcium chloride dihydrate solution and 3 g of a 0.02% aqueous solution of the hydrophilic crosslinked polymer (3 ppm to a getting supersaturated aqueous solution) obtained from the example 15 as a scale suppresant and, furthermore, to the obtained mixture were added 10 g of a 3% aqueous sodium hydrogen carbonate and 7 g of water, so that the total volume became 200 g. An obtained supersaturated aqueous solution of 530 ppm of sodium carbonate was sealed with a stopper and treated by heating at 70° C. for 8 hours. After cooling, an obtained precipitate was taken out by filtration using a membrane filter of hole diameter 0.1 μm and then, a filtrate was analyzed according to JIS (Japanese Industrial Standard) K0101. By the following equation, the calcium carbonate scale-suppresive percentage (%) was obtained. scale-suppresive % =(C-B)/(A-B) here, A: a calcium concentration dissolved in the solution before testing. B: a calcium concentration in the solution, to which a scale inhibitor is not added. C: a calcium concentration in the filtrate after testing. EXAMPLES 16 to 21 The procedure of example 15 was repeated to obtain the hydrophilic crosslinked polymers 16 to 21 except that the kind and amount of a water-soluble oligomer and those of a crosslinking agent and an amount of 48% aqueous sodium hydroxide were as shown in Table 5. Concerning the obtained hydrophilic crosslinked polymers 16 to 21, performance evaluation was carried out similarly to the case of example 15. Results obtained are shown in Table 5. Also, when the obtained hydrophilic crosslinked polymers 16 to 21 were used as fiber-treating agents, water treatment agents, inorganic pigment dispersants and detergents, their evaluation was carried out similarly to the case of example 15. Results obtained are shown in Table 6. TABLE 5__________________________________________________________________________ Example 15 16 17 18 19 20 21__________________________________________________________________________Formulation of rawmaterials (part)Number and amount of aqueous (1) (1) (1) (1) (1) (2) (2)solution of a water-soluble 100 100 100 100 100 100 100oligomerKind and amount of a cross- 50 of 50 of 2.5 of 2.5 of 10 of 50 of 50 oflinking agent citric tartaric D- glycerin citric citric tataric acid acid sorbitol acid acid acid48% NaOH 2 2 2 2 2 2 2Numbering and propertiesof crosslinked polymerNumber (15) (16) (17) (18) (19) (20) (21)Weight-average molecular 1800 1600 1500 1200 1700 1800 1600weight (MW)Acid value (mgKOH/g) 420 400 200 500 450 400 420Viscosity of polymer at 3.8 3.5 2.0 2.5 2.8 3.7 3.520° C. (cp)Whether or not the bonds formed yes yes yes yes yes yes yesbetween main chains have thegroup (II) or (III)Biodegradability ⊚ ⊚ ⊚ ⊚ ⊚ ⊚ ⊚Chelating effect (mg-CaCO.sub.3 /g) 160 150 120 130 160 180 160Dispersing effect (cp) 520 600 700 680 630 400 520__________________________________________________________________________ TABLE 6__________________________________________________________________________ Example 15 16 17 18 19 20 21__________________________________________________________________________Fiber-treating agent Hydrophilic crosslinked polymer (15) (16) (17) (18) (19) (20) (21) Hue value 2.52 2.52 2.51 2.53 2.51 2.53 2.53 Partial color unevenness none none none none none none none Dye dispersion ◯ ◯ ◯ ◯ ◯ ◯ ◯ Feeling ◯ ◯ ◯ ◯ ◯ ◯ ◯ Whiteness 91 92 93 91 92 93 91 Sewing performance 46 45 47 48 47 48 47Inorganic pigment Viscosity of dispersed-in-waterdispersant solution (cps) immediately after production 520 600 700 680 630 400 520 after standing at room 590 630 750 730 720 500 580 temperature for 1 weekWater treatment Scale inhibitor percentage (%) 76 70 72 70 73 71 75agentDetergent Detergency ◯ ◯ ◯ ◯ ◯ ◯ ◯__________________________________________________________________________ Comparative Examples 5 to 8 Concerning the comparative agents described in Tables 7 and 8, whether or not the bond formed between main chains has the group (II) or (III), biodegradability, and chelating and dispersing effects were examined similarly to the case of example 15. Results obtained are shown in Table 7. Also, they were similarly evaluated in using as fiber-treating agents, water treatment agents, inorganic pigment dispersants and detergents. Results obtained are shown in Table 8. TABLE 7__________________________________________________________________________ Comparative example 5 6 7 8__________________________________________________________________________Comparative agent water-soluble water-soluble sodium citrate sodium oligomer (1) oligomer (2) tartarateWhether or not the bonds no no no noformed between main chainshave the group (II) or (III)Biodegradability ⊚ ⊚ ⊚ ⊚Chelating effect 100 120 170 150(mg-CaCO.sub.3 /g)Dispersing effect (cp) 5500 3200 15000 21000__________________________________________________________________________ TABLE 8__________________________________________________________________________ Comparative example 5 6 7 8__________________________________________________________________________Fiber-treating agent Comparative agent water-soluble water-soluble sodium citrate sodium oligomer (1) oligomer (2) tartarate Hue value 2.71 2.75 2.85 2.73 Partial color unevenness yes yes yes yes Dye dispersion X X X X Feeling X X X X Whiteness 82 81 81 82 Sewing performance 65 67 83 88Inorganic pigment Viscosity of dispersed-in-waterdispersant solution (cps) immediately after production 5500 3200 15000 21000 after standing at room 8500 7200 unmeasurable unmeasurable temperature for 1 weekWater treatment agent Scale inhibitor percentage (%) 42 53 41 37Detergent Detergency Δ Δ Δ X__________________________________________________________________________ The hydrophilic crosslinked polymers of this invention have chelating and dispersing effects and are excellent in dispersion into water as well as superior in biodegradability. The process for producing the hydrophilic crosslinked polymers of this invention can make efficiently such crosslinked polymers. When the hydrophilic crosslinked polymers of this invention are used as a detergent, they can elevate detergency by being combined with the detergent, and to degradate the polymers is possible by an organism such as a microorganism. Also, when a detergent combined with the crosslinked polymers is excreted into a river, lake or marsh, it does not cause eutrophication and, therefore, it is useful as a safe builder.
The invention provides biodegradable crosslinked polymers, which have a chelating effect and a dispersing effect to disperse an oily substance and an inorganic substance hardly soluble in water and are excellent in dispersion into water. The crosslinked polymers comprise; an ingredient of molecular weight 5,000 or less in 50% by weight, a bond having at least one of a group (II) represented by the chemical formula --CO--O-- and a group (III) represented by the chemical formula --CO--NH-- as a composition unit between main chains having a water-soluble oligomer structure having the functional group (I) represented by the general formula --COOM (here, M denotes anyone of a hydrogen atom, monovalent metal, divalent metal, trivalent metal, an ammonium group and organic amine group.), and showing a viscosity of 1,000 cP or less at 20° C. by a 20% by weight aqueous solution of the crosslinked polymer.
3
FIELD OF INVENTION The present invention relates generally to compositions for topical application to the skin which comprise 1-aroyl-N-(2-oxo-3-piperidinyl)-2-piperazine carboxamides and the use of such compositions to provide benefits to the skin. BACKGROUND OF THE INVENTION The desmogleins are a family of transmembrane proteins which play an important role in cell adhesion, ensuring that cells within tissue are bound together. In skin, they are major components in desmosomes. Desmosomes are cell-cell adhesion complex between epithelial and certain other cell types. They provide mechanical integrity to keratinocytes by linking to keratin intermediate filaments. Desmogleins form the glue that attaches adjacent skin cells, keeping the skin intact. Desmoglein 1 and 3 are both expressed in stratified squamous epithelia. Desmoglein 1 is dominantly expressed in the differentiated upper layer of epidermis, and Desmoglein 3 is mostly found in basal and suprabasal layers. The differential expression pattern of Desmogleins is important for regulating epidermal functions. Changes of Desmoglein 1 and 3 expression pattern in animal models disrupts keratinocyte proliferation and barrier function of skin. An anticipated benefit for the stimulation of Desmogleins would be an increase in anchoring and adhesion between keratinocytes leading to firmer skin and fewer wrinkles. Collagen is the body's major structural protein and is composed of three protein chains wound together in a tight triple helix. This unique structure gives collagen a greater tensile strength than steel. Approximately 33 percent of the protein in the body is collagen. This protein supports tissues and organs and connects these structures to bones. In fact, bones are also composed of collagen combined with certain minerals such as calcium and phosphorus. Collagen plays a key role in providing the structural scaffolding surrounding cells that helps to support cell shape and differentiation, similar to how steel rods reinforce a concrete block. The mesh-like collagen network binds cells together and provides the supportive framework or environment in which cells develop and function, and tissues and bones heal. Collagen is created by fibroblasts, which are specialized skin cells located in the dermis. Fibroblasts also produce other skin structural proteins such as elastin (a protein which gives the skin its ability to snap back) and glucosaminoglycans (GAGs). GAGs make up the ground substance that keeps the dermis hydrated. In order to signal or turn on the production of skin structural proteins, fibroblast cells have specially shaped receptors on their outside membranes that act as binding sites to which signal molecules with a matching shape can fit. When the receptors are bound by the correct combination of signal molecules (called fibroblast growth factors, or FGFs), the fibroblast begins the production of collagen. The stimulation of collagen gives the skin its strength, durability, and smooth, plump appearance. Dermatopontin is a protein component of the extracellular matrix which is located primarily on the surface of the collagen fibers in the skin. Dermatopontin is believed to play important roles in cell-matrix interactions and matrix assembly (collagen fibrillogenesis). Investigation of dermatopontin knockout mice confirm the involvement of dermatopontin in skin elasticity and collagen accumulation, as the elastic modulus of skin was reported to be 57% lower and collagen content was 40% lower in dermatopontin-null mice than in wild-type mice. Takeda et al., “Targeted disruption of dermatopontin causes abnormal collagen fibrillogenesis,” J. Invest. Dermatol., 2002 Sep;119(3):678-83. It is therefore an object of the invention to provide new compositions and methods for stimulating collagen 1, desmogleins, and/or dermatopontin production. It is a further object of the invention to improve the overall appearance of skin, including treating, reversing, and/or preventing signs of aging, such as skin wrinkles, by stimulating collagen I, desmogleins, and/or dermatopontin production with cosmetic compositions comprising effective amounts of 1-aroyl-N-(2-oxo-3-piperidinyl)-2-piperazine carboxamides. The foregoing discussion is presented solely to provide a better understanding of nature of the problems confronting the art and should not be construed in any way as an admission as to prior art nor should the citation of any reference herein be construed as an admission that such reference constitutes “prior art” to the instant application. SUMMARY OF THE INVENTION In accordance with the foregoing objectives and others, it has surprisingly been found that 1-aroyl-N-(2-oxo-3-piperidinyl)-2-piperazine carboxamides are potent stimulators of collagen I, desmogleins, and/or dermatopontin production and thus are beneficial agents against various signs of intrinsic aging and photo-aging of skin. In one aspect of the invention, cosmetic compositions are provided for improving the aesthetic appearance of skin comprising, in a cosmetically acceptable vehicle, an effective amount of a collagen I, desmogleins, and/or dermatopontin enhancing 1-aroyl-N-(2-oxo-3-piperidinyl)-2-piperazine carboxamide having the structure of formula 1: where R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , and R 7 are independently hydrogen or a group —R 9 -R 10 ; where R 9 represents, independently at each occurrence, a bond (i.e., R 9 is absent) or one of the following: (i) an aliphatic C 1 -C 20 hydrocarbon radical; (ii) a C 1 -C 20 aromatic hydrocarbon radical; (iii) a C 1 -C 20 heteroaryl radical; R 10 is selected independently at each occurrence from hydrogen; —F; —Cl; —Br; —I; —OH, —OR; —NH 2 ; —NHR; —N(R) 2 ; —N(R) 3 + ; —N(R)—OH; —N(→O)(R) 2 ; —O—N(R) 2 ; —N(R)—O—R; —N(R)—N(R) 2 ; —C═N—R; —N═C(R) 2 ; —C═N—N(R) 2 ; —C(═NR)—N(R) 2 ; —SH; —SR; —CN; —NC; —CHO; —CO 2 H; —CO 2 − ; —CO 2 R; —(C═O)—S—R; —O—(C═O)—H; —O—(C═O)—R; —S—(C═O)—R; —(C═O)—NH 2 ; —(C═O)—N(R) 2 ; —(C═O)—NHNH 2 ; —O—(C═O)—NHNH 2 ; —(C═S)—NH 2 ; —(C═S)—N(R) 2 ; —N(R)—CHO; —N(R)—(C═O)—R; —(C═NR)—O—R; —O—(C═NR)—R, —SCN; —NCS; —NSO; —SSR; —N(R)—C(═O)—N(R) 2 ; —N(R)—C(═S)—N(R) 2 ; —SO 2 —R; —O—S(═O) 2 —R; —S(═O) 2 —OR; —N(R)—SO 2 —R; —SO 2 —N(R) 2 ; —O—SO 3 − ; —O—S(═O) 2 —OR; —O—S(═O)—OR; —O—S(═O)—R; —S(═O)—OR; —S(═O)—R; —NO; —NO 2 ; —NO 3 ; —O—NO; —O—NO 2 ; —N 3 ; —N 2 ; —N(C 2 H 4 ); —Si(—R) 3 ; —CF 3 ; —O—CF 3 ; —(C═O)—R; —PR 2 ; —O—P(═O)(OR) 2 ; —P(═O)(OR) 2 ; ═O; ═S; ═NR; an aliphatic C 1 -C 20 hydrocarbon radical; a C 1 -C 20 aromatic hydrocarbon radical; or a C 1 -C 20 heteroaryl radical; where R is independently at each occurrence hydrogen or a saturated, partially saturated, or aromatic C 1 -C 20 hydrocarbon radical, including halo and perhalo derivatives thereof; and where any two adjacent groups R 1 , R 2 , R 3 R 4 , and R 5 may, together with the phenyl ring to which they are attached, form a five-membered or six-membered aliphatic or aromatic ring, optionally substituted with one or more groups R 10 and optionally including one or more heteroatoms selected from O, N, S in the ring. Also provided is a method of treating one or more signs of skin aging comprising topically applying to skin in need thereof a 1-aroyl-N-(2-oxo-3-piperidinyl)-2-piperazine carboxamide according to formula I in an amount effective to enhance collagen I, desmogleins, and/or dermatopontin. In another aspect of the invention, a method of treating, ameliorating, and/or preventing fine lines or wrinkles or sagging in human skin is provided, comprising topically applying to skin in need thereof, including applying directly to a wrinkle or fine line, a composition comprising a 1-aroyl-N-(2-oxo-3-piperidinyl)-2-piperazine carboxamide according to formula I in an amount effective to enhance collagen I, desmogleins, and/or dermatopontin. These and other aspects of the present invention will be better understood by reference to the following detailed description and accompanying figures. DETAILED DESCRIPTION All terms used herein are intended to have their ordinary meaning unless otherwise provided. The present invention provides compositions for topical application which comprise and effective amount of 1-aroyl-N-(2-oxo-3-piperidinyl)-2-piperazine carboxamides or a related compound to treat, reverse, ameliorate and/or prevent signs of skin aging. Such signs of skin aging include without limitation, the following: (a) treatment, reduction, and/or prevention of fine lines or wrinkles, (b) reduction of skin pore size, (c) improvement in skin thickness, plumpness, and/or tautness; (d) improvement in skin suppleness and/or softness; (e) improvement in skin tone, radiance, and/or clarity; (f) improvement in procollagen and/or collagen production; (g) improvement in maintenance and remodeling of elastin; (h) improvement in skin texture and/or promotion of retexturization; (i) improvement in skin barrier repair and/or function; (j) improvement in appearance of skin contours; (k) restoration of skin luster and/or brightness; (l) replenishment of essential nutrients and/or constituents in the skin; (m) decreased by aging and/or menopause; (n) improvement in skin moisturization; and/or (o) increase in skin elasticity and/or resiliency; (p) treatment, reduction, and/or prevention of skin sagging. In practice, the compositions of the invention are applied to skin in need of treatment. That is, skin which suffers from a deficiency or loss in any of the foregoing attributes or which would otherwise benefit from improvement in any of the foregoing skin attributes. In certain preferred embodiments the compositions and methods of the invention are directed to the prevention, treatment, and/or amelioration of fine lines and/or wrinkles in the skin. In this case, the compositions are applied to skin in need of treatment, by which is meant skin having wrinkles and/or fine lines. Preferably, the compositions are applied directly to the fine lines and/or wrinkles. The compositions and methods are suitable for treating fine lines and/or wrinkles on any surface of the skin, including without limitation, the skin of the face, neck, and/or hands. The cosmetic compositions for treating a skin condition associated with loss of collagen and/or elastin fiber comprise, in a cosmetically acceptable vehicle, an amount of a 1-aroyl-N-(2-oxo-3-piperidinyl)-2-piperazine carboxamides effective to enhance collagen I, desmogleins, and/or dermatopontin. These collagen I, desmogleins, and/or dermatopontin enhancing agents may have the structure of formula (I): In formula (I), R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , and R 7 are independently hydrogen or a group —R 9 -R 10 . In one embodiment, at least one of the substituents on the phenyl ring, R 1 , R 2 , R 3 , R 4 , and R 5 , will be a group —R 9 -R 10 while in other embodiments R 3 will be a group —R 9 -R 10 and R 1 , R 2 , R 4 , and R 5 are hydrogen, such that the phenyl ring is substituted in the para position, or R 1 will be a group —R 9 -R 10 and R 2 , R 2 , R 4 , and R 5 are hydrogen, such that the phenyl ring is substituted in the ortho position, or R 2 will be a group —R 9 -R 10 and R 1 , R 3 , R 4 , and R 5 are hydrogen, such that the phenyl ring is substituted in the meta position. In one embodiment, R 7 and/or R 8 represent hydrogen. In other embodiments, R 7 and R 8 independently represent hydrogen or a group —R 9 -R 10 , where R 9 is typically absent and where R 10 is preferably a lower alkyl group (e.g., methyl, ethyl, propyl, butyl, etc.), typically methyl. R 6 may be hydrogen, but will usually be a group —R 9 -R 10 . In some embodiments according to formula (I), at least one of R 6 , R 7 and R 8 represent a group —R 9 -R 10 while in other embodiments R 6 a group —R 9 -R 10 while R 7 and R 8 independently represent hydrogen or lower alkyl group (e.g., methyl, ethyl, propyl, butyl, etc.), typically methyl. In the compounds of formula (I), R 9 represents, independently at each occurrence, a bond (i.e., R 9 is absent) or one of the following: (i) an aliphatic C 1 -C 20 hydrocarbon radical; including an aliphatic C 1 -C 12 hydrocarbon radical, an aliphatic C 1 -C 8 hydrocarbon radical, or an aliphatic C 1 -C 6 hydrocarbon radical, as exemplified by substituted or unsubstituted branched, straight chain or cyclic, alkyl, alkenyl (e.g., vinyl, allyl, etc.), and alkynyl moieties; (ii) a C 6 -C 20 aromatic hydrocarbon radical, including a C 6 -C 12 aromatic hydrocarbon radical, a C 6 -C 10 aromatic hydrocarbon radical, or a C 6 aromatic hydrocarbon radical, as exemplified by substituted or unsubstituted aryl (e.g., phenyl), alkyl-aryl (e.g., benzyl), aryl-alkyl, and the like; (iii) a C 1 -C 20 heteroaryl radical including one or more heteroatoms selected from O, N, and S in the ring; including C 1 -C 12 heteroaromatic radicals, C 1 -C 8 heteroaromatic radicals, and C 1 -C 6 heteroaromatic radicals, as exemplified by heteroaryl, alkyl-heteroaryl, heteroaryl-alkyl and the like. In some embodiments, R 9 is absent at one or more occurrences, such that it represents a bond connecting R 10 directly to the phenyl group or nitrogen atoms of the 1-aroyl-N-(2-oxo-3-piperidinyl)-2-piperazine carboxamide. In other embodiments, R 9 represents, independently at each occurrence, a bond (i.e., R 9 is absent) or a group selected from linear alkyl moieties of the form —(CH 2 ) a — where “a” is an integer from 1 to 6, including, for example, —CH 2 — (methylene), —CH 2 CH 2 —, —CH 2 CH 2 CH 2 —, or —CH 2 CH 2 CH 2 CH 2 —; —C(CH 3 ) 2 —, —CH(CH 3 )CH 2 —, —C(CH 3 ) 2 CH 2 —, —C 6 H 5 —, —CH 2 —C 6 H 5 —; linear alkoxy moieties of the general form —(CH 2 ) a O— or —O(CH 2 ) a — where “a” is an integer from 1 to 6, including for example, —CH 2 O— or —OCH 2 —, —CH 2 CH 2 O— or —OCH 2 CH 2 —, —CH 2 CH 2 CH 2 O— or —OCH 2 CH 2 CH 2 —; —O(CH 2 ) a O— where “a” is as defined above; or a moiety of the form —(CH 2 ) b O(CH 2 ) c —, —(CH 2 ) b S(CH 2 ) c —, or —(CH 2 ) b NR(CH 2 ) c — wherein “b” and “c” are independently an integer from 0 (zero) to 6 and R is as defined above. In some embodiments, R 9 represents a bond, a carbonyl group —(C═O)—, or a methylene group —CH 2 —. R 10 is selected independently at each occurrence from hydrogen; —F; —Cl; —Br; —I; —OH, —OR; —NH 2 ; —NHR; —N(R) 2 ; —N(R) 3 + ; —N(R)—OH; —N(→O)(R) 2 ; —O—N(R) 2 ; —N(R)—O—R; —N(R)—N(R) 2 ; —C═N—R; —N═C(R) 2 ; —C═N—N(R) 2 ; —C(═NR)—N(R) 2 ; —SH; —SR; —CN; —NC; —CHO; —CO 2 H; —CO 2 − ; —CO 2 R; —(C═O)—S—R; —O—(C═O)—H; —O—(C═O)—R; —S—(C═O)—R; —(C═O)—NH 2 ; —(C═O)—N(R) 2 ; —(C═O)—NHNH 2 ; —O—(C═O)—NHNH 2 ; —(C═S)—NH 2 ; —(C═S)—N(R) 2 ; —N(R)—CHO; —N(R)—(C═O)—R; —(C═NR)—O—R; —O—(C═NR)—R, —SCN; —NCS; —NSO; —SSR; —N(R)—C(═O)—N(R) 2 ; —N(R)—C(═S)—N(R) 2 ; —SO 2 —R; —O—S(═O) 2 —R; —S(═O) 2 —OR; —N(R)—SO 2 —N(R) 2 ; —O—SO 3 − ; —O—S(═O) 2 —OR; —O—S(═O)—OR; —O—S(═O)—R; —S(═O)—OR; —S(═O)—R; —NO; —NO 2 ; —NO 3 ; —O—NO; —O—NO 2 ; —N 3 ; —N 2 ; —N(C 2 H 4 ); —Si(—R) 3 ; —CF 3 ; —O—CF 3 ; —(C═O)—R; —PR 2 ; —O—P(═O)(OR) 2 ; —P(═O)(OR) 2 ; ═O; ═S; ═NR; aliphatic C 1 -C 20 hydrocarbon radicals; including aliphatic C 1 -C 12 hydrocarbon radicals, aliphatic C 1 -C 8 hydrocarbon radicals, or an aliphatic C 1 -C 6 hydrocarbon radicals, as exemplified by substituted or unsubstituted branched, straight chain or cyclic, alkyl, alkenyl (e.g., vinyl, allyl, etc.), and alkynyl moieties; C 6 -C 20 aromatic hydrocarbon radicals, including C 6 -C 12 aromatic hydrocarbon radicals, C 6 -C 10 aromatic hydrocarbon radicals, or C 6 aromatic hydrocarbon radicals, as exemplified by substituted or unsubstituted aryl (e.g., phenyl), alkyl-aryl (e.g., benzyl), aryl-alkyl, and the like; or C 1 -C 20 heteroaryl radicals including one or more heteroatoms selected from O, N, and S in the ring; including C 1 -C 12 heteroaromatic radicals, C 1 -C 8 heteroaromatic radicals, and C 1 -C 6 heteroaromatic radicals, as exemplified by heteroaryl, alkyl-heteroaryl, heteroaryl-alkyl and the like. R is independently at each occurrence hydrogen or a saturated, partially saturated, or aromatic C 1 -C 20 hydrocarbon radical, C 1 -C 12 hydrocarbon radical, C 1 -C 8 hydrocarbon radical, or C 1 -C 6 hydrocarbon radical, each optionally including one or more heteroatoms, such as oxygen, sulfur, and nitrogen atoms. Preferably, R is selected from substituted or unsubstituted branched, straight chain or cyclic C 1 -C 20 alkyl, alkenyl, alkynyl, aryl, benzyl, heteroaryl, alkyl-aryl, aryl-alkyl, alkyl-heteroaryl, heteroaryl-alkyl, heteroaryl-aryl, bicyclic alkyl, aryl, or heteroaryl radicals, and combinations thereof; wherein the foregoing radicals may be substituted with any moiety, including, for example, hydroxyl, amino, cyano, halogen, oxo, carboxy, carboxamide, nitro, azo, alkoxyl, alkyl, alkylimino, alkylamino, dialkylamino, thioalkoxy and combinations thereof. R may be, for example, independently at each occurrence, hydrogen, methyl, ethyl, propyl, butyl, pentyl, hexyl, phenyl, benzyl, or the like, including halo and perhalo derivatives thereof. In some embodiments, R will be hydrogen, methyl, ethyl, phenyl or benzyl, most typically methyl or phenyl. In formula (I), it will be further understood that any two adjacent groups R 1 , R 2 , R 3 R 4 , and R 5 may, together with the phenyl ring to which they are attached, form a five-membered or six-membered aliphatic or aromatic ring, optionally substituted with one or more groups R 10 and optionally including one or more heteroatoms selected from O, N, S in the ring. In some embodiments, any two adjacent groups R 1 , R 2 , R 3 R 4 , and R 5 may, together with the phenyl ring to which they are attached, form a heterocyclic ring fused to the phenyl ring, which heterocyclic ring may be aromatic, partially saturated, or fully saturated, including, without limitation, four membered rings (azetidine, oxetane, thietane, etc.), five membered rings (pyrrole, pyrrolidine, furan, oxolane, thiophene, thiolane, pyrazole, imidazole, imidazolidine, oxazole, isoxazole, oxazolidine, thiazole, isothiazole, thiazolidine, dioxolane, dithiolane, 1,2,3-triazole, 1,2,4-triazole, dithiazole, tetrazole, etc.), and six membered rings (piperidine, pyridine, tetrahydropyran, pyran, thiane, thiine, piperazine, diazine, oxazine, thiazine, dithiane, dioxane, dioxin, morpholine, quinoline, etc.). Further, any nitrogen atom may be optionally oxidized to the N-oxide or can be quarternized, for example with loweralkyl halides, such as methyl, ethyl, propyl, and butyl chloride, bromides, and iodides; dialkyl sulfates like dimethyl, diethyl, dibutyl, and diamyl sulfates, long chain halides such as decyl, lauryl, myristyl and stearyl chlorides, bromides and iodides, aralkyl halides such as benzyl and phenethyl bromides, to name a few. In one embodiment according to formula (I), R 1 , R 2 , R 4 , R 5 , R 7 and R 8 represent hydrogen as shown in formula (Ia). where R 3 and R 6 are independently hydrogen or a group —R 9 -R 10 as defined above. In some embodiments, R 3 will be a group —OR (i.e., R 9 is absent and R 10 is —OR), where R represents hydrogen, methyl, ethyl, propyl, iso-propyl, butyl, iso-butyl, sec-butyl, tert-butyl, pentyl, hexyl, phenyl, or benzyl as well as halo and perhalo derivatives thereof, for example trifluoromethyl. In one embodiment, R 3 will be a group —OR where R represents methyl to define a methoxy group in the para position of the phenyl ring as shown in formula (Ib): where R 6 is hydrogen or a group —R 9 -R 10 as defined above. Preferably, R 6 is hydrogen or a group —R 9 -R 10 where R 9 is absent and where R 10 is selected from (i) acyl groups of the form —(C═O)—R, where R is as defined above, but is typically selected from methyl, ethyl, propyl, butyl, pentyl, hexyl, phenyl, toluyl, or benzyl, (preferably phenyl); and (ii) —SO 2 —R groups where R is as defined above, but is typically selected from methyl, ethyl, propyl, butyl, pentyl, hexyl, phenyl, toluyl, or benzyl, (preferably methyl). 1-aroyl-N-(2-oxo-3-piperidinyl)-2-piperazine carboxamide compounds according to formula (Ib) where R 6 is —(C═O)—(C 6 H 5 ) (i.e., benzoyl) or —SO 2 —CH 3 are commercially available from Analyticon GmbH (Berlin, Germany). In a particular embodiment, a cosmetic composition comprises, in a cosmetically acceptable vehicle, preferably a water-in-oil or oil-in-water emulsion, from about 0.0001% to about 90% by weight of a 1-aroyl-N-(2-oxo-3-piperidinyl)-2-piperazine carboxamide having the structure: or a cosmetically acceptable salt thereof. In another particular embodiment, a cosmetic composition comprises, in a cosmetically acceptable vehicle, preferably a water-in-oil or oil-in-water emulsion, from about 0.0001% to about 90% by weight of a 1-aroyl-N-(2-oxo-3-piperidinyl)-2-piperazine carboxamide having the structure: or a cosmetically acceptable salt thereof. The compounds of formula (I) comprise one stereocenter on the piperazine ring and one sterocenter on the lactam ring. Each of these sterocenters may be in the R or S configuration. Accordingly, the compounds according to formula (i) may exist as a pure (R,R), (R,S), (S,R), or (S,S) diastereomer with respect to these two chiral centers or may comprise a mixture of two or more diastereomer. By “pure” is meant that the particular diastereomer comprises at least 95% by weight of the total weight of formula (I) compound, and preferably at least 98% or at least 99% by weight. The invention embraces the use of cosmetically or pharmaceutically acceptable (e.g., non-toxic and/or non-irritating) salts. Examples of the salts of the compounds in the present invention include salts with alkali metals such as sodium and potassium; salts with alkaline-earth metals such as calcium and magnesium; salts with amines such as monoethanolamine; salts with inorganic acids such as hydrochloric acid and sulfuric acid; and salts with organic acids such as citric acid and acetic acid. Special mention may be made of hydrochloride salts. The cosmetic compositions according to the invention can be formulated in a variety of forms for topical application and will comprise from about 0.0001% to about 90% by weight of one or more compounds according to formula (I), and preferably will comprise from about 0.001% to about 25% by weight, and more preferably from about 0.01% to about 10% by weight. The compositions will comprise and effective amount of the 1-aroyl-N-(2-oxo-3-piperidinyl)-2-piperazine carboxamide compounds according to formula (I), by which is meant an amount sufficient to enhance collagen I, desmogleins, and/or dermatopontin in given area of skin when topically applied thereto. The composition may be formulated in a variety of product forms, such as, for example, a lotion, cream, serum, spray, aerosol, cake, ointment, essence, gel, paste, patch, pencil, towelette, mask, stick, foam, elixir, concentrate, and the like, particularly for topical administration. Preferably the composition is formulated as a lotion, cream, ointment, or gel. The compositions can include a cosmetically acceptable vehicle. Such vehicles may take the form of any known in the art suitable for application to skin and may include water; vegetable oils; mineral oils; esters such as octal palmitate, isopropyl myristate and isopropyl palmitate; ethers such as dicapryl ether and dimethyl isosorbide; alcohols such as ethanol and isopropanol; fatty alcohols such as cetyl alcohol, cetearyl alcohol, stearyl alcohol and biphenyl alcohol; isoparaffins such as isooctane, isododecane and is hexadecane; silicone oils such as cyclomethicone, dimethicone, dimethicone cross-polymer, polysiloxanes and their derivatives, preferably organomodified derivatives; hydrocarbon oils such as mineral oil, petrolatum, isoeicosane and polyisobutene; polyols such as propylene glycol, glycerin, butylene glycol, pentylene glycol and hexylene glycol; waxes such as beeswax and botanical waxes; or any combinations or mixtures of the foregoing. The vehicle may comprise an aqueous phase, an oil phase, an alcohol, a silicone phase or mixtures thereof. The cosmetically acceptable vehicle may also comprise an emulsion. Non-limiting examples of suitable emulsions include water-in-oil emulsions, oil-in-water emulsions, silicone-in-water emulsions, water-in-silicone emulsions, wax-in-water emulsions, water-oil-water triple emulsions or the like having the appearance of a cream, gel or microemulsions. The emulsion may include an emulsifier, such as a nonionic, anionic or amphoteric surfactant. The oil phase of the emulsion preferably has one or more organic compounds, including emollients; humectants (such as propylene glycol and glycerin); other water-dispersible or water-soluble components including thickeners such as veegum or hydroxyalkyl cellulose; gelling agents, such as high MW polyacrylic acid, i.e. CARBOPOL 934; and mixtures thereof. The emulsion may have one or more emulsifiers capable of emulsifying the various components present in the composition. The compounds suitable for use in the oil phase include without limitation, vegetable oils; esters such as octyl palmitate, isopropyl myristate and isopropyl palmitate; ethers such as dicapryl ether; fatty alcohols such as cetyl alcohol, stearyl alcohol and behenyl alcohol; isoparaffins such as isooctane, isododecane and isohexadecane; silicone oils such as dimethicones, cyclic silicones, and polysiloxanes; hydrocarbon oils such as mineral oil, petrolatum, isoeicosane and polyisobutene; natural or synthetic waxes; and the like. Suitable hydrophobic hydrocarbon oils may be saturated or unsaturated, have an aliphatic character and be straight or branched chained or contain alicyclic or aromatic rings. The oil-containing phase may be composed of a singular oil or mixtures of different oils. Hydrocarbon oils include those having 6-20 carbon atoms, more preferably 10-16 carbon atoms. Representative hydrocarbons include decane, dodecane, tetradecane, tridecane, and C 8-20 isoparaffins. Paraffinic hydrocarbons are available from Exxon under the ISOPARS trademark, and from the Permethyl Corporation. In addition, C 8-20 paraffinic hydrocarbons such as C12 isoparaffin (isododecane) manufactured by the Permethyl Corporation having the tradename Permethyl 99ATM are also contemplated to be suitable. Various commercially available C 16 isoparaffins, such as isohexadecane (having the tradename Permethyl RTM) are also suitable. Examples of preferred volatile hydrocarbons include polydecanes such as isododecane and isodecane, including for example, Permethyl-99A (Presperse Inc.) and the C 7 -C 8 through C 12 -C 15 isoparaffins such as the Isopar Series available from Exxon Chemicals. A representative hydrocarbon solvent is isododecane. The oil phase may comprise one or more waxes, including for example, rice bran wax, carnauba wax, ouricurry wax, candelilla wax, montan waxes, sugar cane waxes, ozokerite, polyethylene waxes, Fischer-Tropsch waxes, beeswax, microcrystaline wax, silicone waxes, fluorinated waxes, and any combination thereof. Non-limiting emulsifiers included emulsifying waxes, emulsifying polyhydric alcohols, polyether polyols, polyethers, mono- or di-ester of polyols, ethylene glycol mono-stearates, glycerin mono-stearates, glycerin di-stearates, silicone-containing emulsifiers, soya sterols, fatty alcohols such as cetyl alcohol, fatty acids such as stearic acid, fatty acid salts, and mixtures thereof. The preferred emulsifiers include soya sterol, cetyl alcohol, stearic acid, emulsifying wax, and mixtures thereof. Other specific emulsifiers that can be used in the composition of the present invention include, but are not limited to, one or more of the following: sorbitan esters; polyglyceryl-3-diisostearate; sorbitan monostearate, sorbitan tristearate, sorbitan sesquioleate, sorbitan monooleate; glycerol esters such as glycerol monostearate and glycerol monooleate; polyoxyethylene phenols such as polyoxyethylene octyl phenol and polyoxyethylene nonyl phenol; polyoxyethylene ethers such as polyoxyethylene cetyl ether and polyoxyethylene stearyl ether; polyoxyethylene glycol esters; polyoxyethylene sorbitan esters; dimethicone copolyols; polyglyceryl esters such as polyglyceryl-3-diisostearate; glyceryl laurate; Steareth-2, Steareth-10, and Steareth-20, to name a few. Additional emulsifiers are provided in the INCI Ingredient Dictionary and Handbook 11th Edition 2006, the disclosure of which is hereby incorporated by reference. These emulsifiers typically will be present in the composition in an amount from about 0.001% to about 10% by weight, in particular in an amount from about 0.01% to about 5% by weight, and more preferably, below 1% by weight. The oil phase may comprise one or more volatile and/or non-volatile silicone oils. Volatile silicones include cyclic and linear volatile dimethylsiloxane silicones. In one embodiment, the volatile silicones may include cyclodimethicones, including tetramer (D4), pentamer (D5), and hexamer (D6) cyclomethicones, or mixtures thereof. Particular mention may be made of the volatile cyclomethicone-hexamethyl cyclotrisiloxane, octamethyl-cyclotetrasiloxane, and decamethyl-cyclopentasiloxane. Suitable dimethicones are available from Dow Corning under the name Dow Corning 200® Fluid and have viscosities ranging from 0.65 to 600,000 centistokes or higher. Suitable non-polar, volatile liquid silicone oils are disclosed in U.S. Pat. No. 4,781,917, herein incorporated by reference in its entirety. Additional volatile silicones materials are described in Todd et al., “Volatile Silicone Fluids for Cosmetics”, Cosmetics and Toiletries, 91:27-32 (1976), herein incorporated by reference in its entirety. Linear volatile silicones generally have a viscosity of less than about 5 centistokes at 25° C., whereas the cyclic silicones have viscosities of less than about 10 centistokes at 25° C. Examples of volatile silicones of varying viscosities include Dow Corning 200, Dow Corning 244, Dow Corning 245, Dow Corning 344, and Dow Corning 345, (Dow Corning Corp.); SF-1204 and SF-1202 Silicone Fluids (G.E. Silicones), GE 7207 and 7158 (General Electric Co.); and SWS-03314 (SWS Silicones Corp.). Linear, volatile silicones include low molecular weight polydimethylsiloxane compounds such as hexamethyldisiloxane, octamethyltrisiloxane, decamethyltetrasiloxane, and dodecamethylpentasiloxane, to name a few. Non-volatile silicone oils will typically comprise polyalkylsiloxanes, polyarylsiloxanes; polyalkylarylsiloxanes, or mixtures thereof. Polydimethylsiloxanes are preferred non-volatile silicone oils. The non-volatile silicone oils will typically have a viscosity from about 10 to about 60,000 centistokes at 25° C., preferably between about 10 and about 10,000 centistokes, and more preferred still between about 10 and about 500 centistokes; and a boiling point greater than 250° C. at atmospheric pressure. Non limiting examples include dimethyl polysiloxane (dimethicone), phenyl trimethicone, and diphenyldimethicone. The volatile and non-volatile silicone oils may optionally be substituted will various functional groups such as alkyl, aryl, amine groups, vinyl, hydroxyl, haloalkyl groups, alkylaryl groups, and acrylate groups, to name a few. The water-in-silicone emulsion may be emulsified with a nonionic surfactant (emulsifier) such as, for example, polydiorganosiloxane-polyoxyalkylene block copolymers, including those described in U.S. Pat. No. 4,122,029, the disclosure of which is hereby incorporated by reference. These emulsifiers generally comprise a polydiorganosiloxane backbone, typically polydimethylsiloxane, having side chains comprising -(EO)m- and/or —(PO)n— groups, where EO is ethyleneoxy and PO is 1,2-propyleneoxy, the side chains being typically capped or terminated with hydrogen or lower alkyl groups (e.g., C 1-6 , typically C 1-3 ). Other suitable water-in-silicone emulsifiers are disclosed in U.S. Pat. No. 6,685,952, the disclosure of which is hereby incorporated by reference herein. Commercially available water-in-silicone emulsifiers include those available from Dow Corning under the trade designations 3225C and 5225C FORMULATION AID; SILICONE SF-1528 available from General Electric; ABIL EM 90 and EM 97, available from Goldschmidt Chemical Corporation (Hopewell, Va.); and the SILWET series of emulsifiers sold by OSI Specialties (Danbury, Conn.). Examples of water-in-silicone emulsifiers include, but are not limited to, dimethicone PEG 10/15 crosspolymer, dimethicone copolyol, cetyl dimethicone copolyol, PEG-15 lauryl dimethicone crosspolymer, laurylmethicone crosspolymer, cyclomethicone and dimethicone copolyol, dimethicone copolyol (and) caprylic/capric triglycerides, polyglyceryl-4 isostearate (and) cetyl dimethicone copolyol (and) hexyl laurate, and dimethicone copolyol (and) cyclopentasiloxane. Preferred examples of water-in-silicone emulsifiers include, without limitation, PEG/PPG-18/18 dimethicone (trade name 5225C, Dow Corning), PEG/PPG-19/19 dimethicone (trade name BY25-337, Dow Corning), Cetyl PEG/PPG-10/1 dimethicone (trade name Abil EM-90, Goldschmidt Chemical Corporation), PEG-12 dimethicone (trade name SF 1288, General Electric), lauryl PEG/PPG-18/18 methicone (trade name 5200 FORMULATION AID, Dow Corning), PEG-12 dimethicone crosspolymer (trade name 9010 and 9011 silicone elastomer blend, Dow Corning), PEG-10 dimethicone crosspolymer (trade name KSG-20, Shin-Etsu), and dimethicone PEG-10/15 crosspolymer (trade name KSG-210, Shin-Etsu). The water-in-silicone emulsifiers typically will be present in the composition in an amount from about 0.001% to about 10% by weight, in particular in an amount from about 0.01% to about 5% by weight, and more preferably, below 1% by weight. The aqueous phase of the emulsion may include one or more additional solvents, including lower alcohols, such as ethanol, isopropanol, and the like. The volatile solvent may also be a cosmetically acceptable ester such as butyl acetate or ethyl acetate; ketones such as acetone or ethyl methyl ketone; or the like. The oil-containing phase will typically comprise from about 10% to about 99%, preferably from about 20% to about 85%, and more preferably from about 30% to about 70% by weight, based on the total weight of the emulsion, and the aqueous phase will typically comprise from about 1% to about 90%, preferably from about 5% to about 70%, and more preferably from about 20% to about 60% by weight of the total emulsion. The aqueous phase will typically comprise from about 25% to about 100%, more typically from about 50% to about 95% by weight water. The compositions may include liposomes. The liposomes may comprise other additives or substances and/or may be modified to more specifically reach or remain at a site following administration. The composition may optionally comprise other cosmetic actives and excipients, obvious to those skilled in the art including, but not limited to, fillers, emulsifying agents, antioxidants, surfactants, film formers, chelating agents, gelling agents, thickeners, emollients, humectants, moisturizers, vitamins, minerals, viscosity and/or rheology modifiers, sunscreens, keratolytics, depigmenting agents, retinoids, hormonal compounds, alpha-hydroxy acids, alpha-keto acids, anti-mycobacterial agents, antifungal agents, antimicrobials, antivirals, analgesics, lipidic compounds, anti-allergenic agents, H1 or H2 antihistamines, anti-inflammatory agents, anti-irritants, antineoplastics, immune system boosting agents, immune system suppressing agents, anti-acne agents, anesthetics, antiseptics, insect repellents, skin cooling compounds, skin protectants, skin penetration enhancers, exfollients, lubricants, fragrances, colorants, depigmenting agents, hypopigmenting agents, preservatives, stabilizers, pharmaceutical agents, photostabilizing agents, sunscreens, and mixtures thereof. In addition to the foregoing, the cosmetic compositions of the invention may contain any other compound for the treatment of skin disorders. Colorants may include, for example, organic and inorganic pigments and pearlescent agents. Suitable inorganic pigments include, but are not limited to, titanium oxide, zirconium oxide and cerium oxide, as well as zinc oxide, iron oxide, chromium oxide and ferric blue. Suitable organic pigments include barium, strontium, calcium, and aluminium lakes and carbon black. Suitable pearlescent agents include mica coated with titanium oxide, with iron oxide, or with natural pigment. Various fillers and additional components may be added. Fillers are normally present in an amount of about 0 weight % to about 20 weight %, based on the total weight of the composition, preferably about 0.1 weight % to about 10 weight %. Suitable fillers include without limitation silica, treated silica, talc, zinc stearate, mica, kaolin, Nylon powders such as Orgasol™, polyethylene powder, Teflon™, starch, boron nitride, copolymer microspheres such as Expancel™ (Nobel Industries), Polytrap™ (Dow Corning) and silicone resin microbeads (Tospearl™ from Toshiba), and the like. In one embodiment of the invention, the compositions may include additional skin actives such as, but are not limited to, botanicals, keratolytic agents, desquamating agents, keratinocyte proliferation enhancers, collagenase inhibitors, elastase inhibitors, depigmenting agents, anti-inflammatory agents, steroids, anti-acne agents, antioxidants, salicylic acid or salicylates, thiodipropionic acid or esters thereof, and advanced glycation end-product (AGE) inhibitors. In a specific embodiment, the composition may comprise at least one additional botanical, such as, for example, a botanical extract, an essential oil, or the plant itself. Suitable botanicals include, without limitation, extracts from Abies pindrow, Acacia catechu, Anogeissus latifolia, Asmunda japonica, Azadirachta indica, Butea frondosa, Butea monosperma, Cedrus deodara, Emblica officinalis, Ficus benghalensis, Glycyrrhiza glabra, Ilex purpurea Hassk, Innula racemosa, Ligusticum chiangxiong, Ligusticum lucidum, Mallotus philippinensis, Mimusops elengi, Morinda citrifolia, Moringa oleifera, Naringi crenulata, Nerium indicum, Psoralea corylifolia, Stenoloma chusana, Terminalia bellerica , tomato glycolipid and mixtures thereof. The composition may comprise additional active ingredients having anti-aging benefits, as it is contemplated that synergistic improvements may be obtained with such combinations. Exemplary anti-aging components include, without limitation, botanicals (e.g., Butea Frondosa extract); thiodipropionic acid (TDPA) and esters thereof; retinoids (e.g., all-trans retinoic acid, 9-cis retinoic acid, phytanic acid and others); hydroxy acids (including alpha-hydroxyacids and beta-hydroxyacids), salicylic acid and salicylates; exfoliating agents (e.g., glycolic acid, 3,6,9-trioxaundecanedioic acid, etc.), estrogen synthetase stimulating compounds (e.g., caffeine and derivatives); compounds capable of inhibiting 5 alpha-reductase activity (e.g., linolenic acid, linoleic acid, finasteride, and mixtures thereof); barrier function enhancing agents (e.g., ceramides, glycerides, cholesterol and its esters, alpha-hydroxy and omega-hydroxy fatty acids and esters thereof, etc.); collagenase inhibitors; and elastase inhibitors; to name a few. Exemplary retinoids include, without limitation, retinoic acid (e.g., all-trans or 13-cis) and derivatives thereof, retinol (Vitamin A) and esters thereof, such as retinol palmitate, retinol acetate and retinol propionate, and salts thereof. In another embodiment, the topical compositions of the present invention may also include one or more of the following: a skin penetration enhancer, an emollient, a skin plumper, an optical diffuser, a sunscreen, an exfoliating agent, and an antioxidant. An emollient provides the functional benefits of enhancing skin smoothness and reducing the appearance of fine lines and coarse wrinkles. Examples include isopropyl myristate, petrolatum, isopropyl lanolate, silicones (e.g., methicone, dimethicone), oils, mineral oils, fatty acid esters, or any mixtures thereof. The emollient may be preferably present from about 0.1 wt % to about 50 wt % of the total weight of the composition. A skin plumper serves as a collagen enhancer to the skin. An example of a suitable, and preferred, skin plumper is palmitoyl oligopeptide. Other skin plumpers are collagen and/or other glycosaminoglycan (GAG) enhancing agents. When present, the skin plumper may comprise from about 0.1 wt % to about 20 wt % of the total weight of the composition. An optical diffuser is a particle that changes the surface optometrics of skin, resulting in a visual blurring and softening of, for example, lines and wrinkles. Examples of optical diffusers that can be used in the present invention include, but are not limited to, boron nitride, mica, nylon, polymethylmethacrylate (PMMA), polyurethane powder, sericite, silica, silicone powder, talc, Teflon, titanium dioxide, zinc oxide, or any mixtures thereof. When present, the optical diffuser may be present from about 0.01 wt % to about 20 wt % of the total weight of the composition. A sunscreen for protecting the skin from damaging ultraviolet rays may also be included. Preferred sunscreens are those with a broad range of UVB and UVA protection, such as octocrylene, avobenzone (Parsol 1789), octyl methoxycinnamate, octyl salicylate, oxybenzone, homosylate, benzophenone, camphor derivatives, zinc oxide, and titanium dioxide. When present, the sunscreen may comprise from about 0.01 wt % to about 70 wt % of the composition. Suitable exfoliating agents include, for example, alpha-hydroxyacids, beta-hydroxyacids, oxaacids, oxadiacids, and their derivatives such as esters, anhydrides and salts thereof. Suitable hydroxy acids include, for example, glycolic acid, lactic acid, malic acid, tartaric acid, citric acid, 2-hydroxyalkanoic acid, mandelic acid, salicylic acid and derivatives thereof. A preferred exfoliating agent is glycolic acid. When present, the exfoliating agent may comprise from about 0.1 wt % to about 80 wt % of the composition. An antioxidant functions, among other things, to scavenge free radicals from skin to protect the skin from environmental aggressors. Examples of antioxidants that may be used in the present compositions include compounds having phenolic hydroxy functions, such as ascorbic acid and its derivatives/esters; beta-carotene; catechins; curcumin; ferulic acid derivatives (e.g. ethyl ferulate, sodium ferulate); gallic acid derivatives (e.g., propyl gallate); lycopene; reductic acid; rosmarinic acid; tannic acid; tetrahydrocurcumin; tocopherol and its derivatives; uric acid; or any mixtures thereof. Other suitable antioxidants are those that have one or more thiol functions (—SH), in either reduced or non-reduced form, such as glutathione, lipoic acid, thioglycolic acid, and other sulfhydryl compounds. The antioxidant may be inorganic, such as bisulfites, metabisulfites, sulfites, or other inorganic salts and acids containing sulfur. Compositions of the present invention may comprise an antioxidant preferably from about 0.001 wt % to about 10 wt %, and more preferably from about 0.01 wt % to about 5 wt %, of the total weight of the composition. Other conventional additives include: vitamins, such as tocopherol and ascorbic acid; vitamin derivatives such as ascorbyl monopalmitate; thickeners such as hydroxyalkyl cellulose; gelling agents; structuring agents such as bentonite, smectite, magnesium aluminum silicate and lithium magnesium silicate; metal chelating agents such as EDTA; pigments such as zinc oxide and titanium dioxide; colorants; emollients; and humectants. It is preferred that the composition be essentially free of components having a strong oxidizing potential, including for example, organic or inorganic peroxides. By “essentially free of” these components is meant that the amounts present are insufficient to have a measurable impact on the collagen I, desmogleins, and/or dermatopontin enhancing activity of the 1-aroyl-N-(2-oxo-3-piperidinyl)-2-piperazine carboxamides. In some embodiments, this will be, on a molar basis in relation to the amount of 1-aroyl-N-(2-oxo-3-piperidinyl)-2-piperazine carboxamide, less than 1%. In one embodiment, the composition of the invention comprising a 1-aroyl-N-(2-oxo-3-piperidinyl)-2-piperazine carboxamide may have a pH between about 1 and about 8. In certain embodiments, the pH of the composition will be acidic, i.e., less than 7.0, and preferably will be between about 2 and about 7, more preferably between about 3.5 and about 5.5. The invention provides a method for treating aging skin by topically applying a composition comprising a 1-aroyl-N-(2-oxo-3-piperidinyl)-2-piperazine carboxamide, preferably in a cosmetically acceptable vehicle, over the affected area for a period of time sufficient to reduce, ameliorate, reverse or prevent dermatological signs of aging. This method is particularly useful for treating signs of skin photoaging and intrinsic aging. Generally, the improvement in the condition and/or aesthetic appearance is selected from the group consisting of: reducing dermatological signs of chronological aging, photo-aging, hormonal aging, and/or actinic aging; preventing and/or reducing the appearance of lines and/or wrinkles; reducing the noticeability of facial lines and wrinkles, facial wrinkles on the cheeks, forehead, perpendicular wrinkles between the eyes, horizontal wrinkles above the eyes, and around the mouth, marionette lines, and particularly deep wrinkles or creases; preventing, reducing, and/or diminishing the appearance and/or depth of lines and/or wrinkles; improving the appearance of suborbital lines and/or periorbital lines; reducing the appearance of crow's feet; rejuvenating and/or revitalizing skin, particularly aging skin; reducing skin fragility; preventing and/or reversing of loss of glycosaminoglycans and/or collagen; ameliorating the effects of estrogen imbalance; preventing skin atrophy; preventing, reducing, and/or treating hyperpigmentation; minimizing skin discoloration; improving skin tone, radiance, clarity and/or tautness; preventing, reducing, and/or ameliorating skin sagging; improving skin firmness, plumpness, suppleness and/or softness; improving procollagen and/or collagen production; improving skin texture and/or promoting retexturization; improving skin barrier repair and/or function; improving the appearance of skin contours; restoring skin luster and/or brightness; minimizing dermatological signs of fatigue and/or stress; resisting environmental stress; replenishing ingredients in the skin decreased by aging and/or menopause; improving communication among skin cells; increasing cell proliferation and/or multiplication; increasing skin cell metabolism decreased by aging and/or menopause; retarding cellular aging; improving skin moisturization; enhancing skin thickness; increasing skin elasticity and/or resiliency; enhancing exfoliation; improving microcirculation; decreasing and/or preventing cellulite formation; and any combinations thereof. Without wishing to be bound by any particular theory, it is believed that the compositions of the present invention enhance and improve the aesthetic appearance of skin by stimulation of collagen and/or by improving the cell-to-cell adhesion between keratinocytes through the stimulation of Desmogleins. The composition will typically be applied to the skin one, two, or three times daily for as long as is necessary to achieve desired anti-aging results. The treatment regiment may comprise daily application for at least one week, at least two weeks, at least four weeks, at least eight weeks, or at least twelve weeks. Chronic treatment regimens are also contemplated. The 1-aroyl-N-(2-oxo-3-piperidinyl)-2-piperazine carboxamide active component is topically applied to an “individual in need thereof,” by which is meant an individual that stands to benefits from reducing visible signs of skin damage or aging. In a specific embodiment, the 1-aroyl-N-(2-oxo-3-piperidinyl)-2-piperazine carboxamide component is provided in a pharmaceutically, physiologically, cosmetically, and dermatologically-acceptable vehicle, diluent, or carrier, where the composition is topically applied to an affected area of skin and left to remain on the affected area in an amount effective for improving the condition and aesthetic appearance of skin. In one embodiment, methods for treating fine lines and wrinkles comprise topically applying the inventive 1-aroyl-N-(2-oxo-3-piperidinyl)-2-piperazine carboxamide compositions to the skin of an individual in need thereof, e.g., topically application directly to the fine line and/or wrinkle in an amount and for a time sufficient to reduce the severity of the fine lines and/or wrinkles or to prevent or inhibit the formation of new fine lines and/or wrinkles. The effect of a composition on the formation or appearance of fine lines and wrinkles can be evaluated qualitatively, e.g., by visual inspection, or quantitatively, e.g., by microscopic or computer assisted measurements of wrinkle morphology (e.g., the number, depth, length, area, volume and/or width of wrinkles per unit area of skin). This embodiment includes treatment of wrinkles on the skin of the hands, arms, legs, neck, chest, and face, including the forehead, It is also contemplated that the compositions of the invention will be useful for treating thin skin by topically applying the composition to thin skin of an individual in need thereof. “Thin skin” is intended to include skin that is thinned due to chronological aging, menopause, or photo-damage. In some embodiments, the treatment is for thin skin in men, whereas other embodiments treat thin skin in women, pre-menopausal or post-menopausal, as it is believed that skin thins differently with age in men and women, and in particular in women at different stages of life. The method of the invention may be employed prophylactically to forestall aging including in patients that have not manifested signs of skin aging, most commonly in individuals under 25 years of age. The method may also reverse or treat signs of aging once manifested as is common in patients over 25 years of age. EXAMPLES 1. Example 1 Stimulation of Collagen I Human dermal fibroblasts (Cascade Biologics) were cultured in 96-well tissue culture plates in growth medium (DMEM, 5% FBS, 1% L-Glut, and 1% antibiotics) and incubated for 24 hours at 37° C. Cells were then treated with test active diluted in growth medium and incubated for 48 hours at 37° C., after which the culture media was collected and assayed for the presence of procollagen 1. Procollagen 1 levels were assayed using an ELISA kit from Takara (Procollagen Type-1 C-Peptide EIA Kit, Takara Bio Inc.) as per manufacturer's instructions. Fibroblasts treated with 5 μg/ml of 1-aroyl-N-(2-oxo-3-piperidinyl)-2-piperazine carboxamide showed a 75.4% increase in collagen synthesis compared to control. 2. Example 2 Stimulation of Desmogleins Normal human keratinocytes were cultured in 96 well tissue culture treated plates in Epilife medium with growth supplements (Cascade Biologics Inc.). Cells were treated with test material or a dimethylsulfoxide vehicle control diluted in growth medium for 24 hours in a humidified 37° C. incubator with 10% CO2. After incubation, growth medium from each plate was removed and 100 μl of lysis buffer was added to each of the wells and placed in the humidified 37° C. incubator with 10% CO 2 for 30 minutes. At the end of the incubation period, the cells were collected in freezer plates and placed in a −80° C. freezer, until analysis. Changes in mRNA for Desmoglein 3 (DSG3) after treatment were analysed using Panomics Quantigene multiplex assay that employs branched DNA technology. The increase (%) in mRNA for each endpoint was calculated by comparing the test results of the extract to the control. Keratinocytes treated with 1-aroyl-N-(2-oxo-3-piperidinyl)-2-piperazine carboxamide at a concentration of 0.0005% showed a 95% increase in Desmoglein 1 expression after 24 hours. The effect observed was an average of three samples assayed and was statistically significant at p<0.05. Treatment with 0.00005% of the test material did not show a statistically significant increase in Desmoglein 1 expression. 3. Example 3 Stimulation of Dermatopontin Production Normal human dermal fibroblasts were cultured in 96 well tissue culture treated plates, containing appropriate culture medium. Cells were treated with 1-aroyl-N-(2-oxo-3-piperidinyl)-2-piperazine carboxamide test material, diluted in growth medium, for 24 hours in a humidified 37° C. incubator with 10% CO 2 . After incubation, growth medium from each plate was removed and 100 μl of lysis buffer was added to the wells and placed in 37° C. incubator with 10% CO 2 for 30 minutes. At the end of incubation, the cells were collected in freezer plates and placed in −80° C. freezer, until analysis. Changes in mRNA for Dermatopontin after treatment were analysed using Panomics Quantigene multiplex assay that employs a branched DNA technology. Percent increase in mRNA for MT2A was calculated by comparing the test results to that of the vehicle control. Fibroblasts treated with 0.0005% or 0.00005% of 1-aroyl-N-(2-oxo-3-piperidinyl)-2-piperazine carboxamide showed a 62% and 43% stimulation in mRNA levels for Dermatopontin respectively. All results reported are statistically significant at p<0.05. 4. Example 4 Representative Formulations Representative formulations of skin care products comprising effective amounts of 1-aroyl-N-(2-oxo-3-piperidinyl)-2-piperazine carboxamide active agent are provided in Table 1. TABLE 1 Concentration (wt. %) Description Purpose Formula 1 Formula 2 Formula 3 Formula 4 Deionized water diluent qs 100% qs 100% qs 100% qs 100% Acrylates/C10-30 Alkyl Acrylate emulsifier 1 1 1 1 Crosspolymer Cetyl Ethylhexanoate emollient 10 10 10 10 C12-15 Alkyl Benzoate emollient 3.9 3.9 3.9 3.9 Isopropyl Isostearate emollient 3 3 3 3 Diisopropyl dimer dillinoleate emollient 0.1 0.1 0.1 0.1 Tocopheryl acetate antioxidant 0.5 0.5 0.5 0.5 Butylene glycol humectant 2 2 2 2 Propylene glycol humectant 1 1 1 1 Dimethicone PEG-7 isostearate co-emulsifier 0.5 0.5 0.5 0.5 Methyl gluceth-20 humectant 0.5 0.5 0.5 0.5 Triethanolamine neutralizer 1 1 1 1 Acrylates/acrylamide emulsifier 1.5 1.5 1.5 1.5 copolymer/mineral oil DMDM preservative 0.4 0.4 0.4 0.4 Hydantoin/Iodopropynylbutylcarbonate 1-aroyl-N-(2-oxo-3-piperidinyl)-2- active 0.3 0.03 0.01 0.005 piperazine carboxamide Formulas 1-4 are topically applied to skin, including skin of the face, to prevent, treat, and/or reduce signs of photo-aging and/or intrinsic aging, such as fine lines and wrinkles. The formulas are topically applied to the skin for an amount of time sufficient to provide a clinically measurable reduction in one or more signs of skin aging, which typically entails once, twice, or three-times daily treatment for one, two, or three weeks up to about eight weeks or more, including chronic treatment. All references including patent applications and publications cited herein are incorporated herein by reference in their entirety and for all purposes to the same extent as if each individual publication or patent or patent application was specifically and individually indicated to be incorporated by reference in its entirety for all purposes. Many modifications and variations of this invention can be made without departing from its spirit and scope, as will be apparent to those skilled in the art. The specific embodiments described herein are offered by way of example only, and the invention is to be limited only by the terms of the appended claims, along with the full scope of equivalents to which such claims are entitled.
Cosmetic compositions comprising 1-aroyl-N-(2-oxo-3-piperidinyl)-2-piperazine carboxamides and methods of using such compositions to impart anti-aging benefits to the skin are disclosed. The 1-aroyl-N-(2-oxo-3-piperidinyl)-2-piperazine carboxamides are believed to have modulatory activity against one or more biochemical pathways implicated in skin aging.
0
BACKGROUND OF THE INVENTION [0001] Producers of metal strips are using cold roll processes for producing a metal strip with specified mechanical properties, surface properties and thickness. In the cold rolling process, the strip passes through a nip or roll gap existing between two counter-rotating rolls for reducing the thickness of the strip and providing the required surface quality. During the cold roll process a lot of heat is created in the nip due to the friction between the rolls and the strip and due to the deformation of the strip material. This heat has negative influences on the material and surface properties. [0002] In conventional cold rolling processes, liquids, such as oil, water or emulsions, are used as a cooling lubricant for reducing the friction and the heat in the roll gap. Often, these liquids remain on the surface after the cold rolling where they cause negative effects. E.g. water or aqueous emulsions on the surface of the metal strip lead to corrosion, i.e. rust formation. Further, oil residues on the surface have to be removed therefrom as far as possible prior to further processing of the metal strip. Both, the cleaning process and the rejects due to aqueous or oily residues on the surface of the metal strip cause high costs in rework and scrap. [0003] Accordingly, it is an object of the present invention to provide a process and a roll stand for cold rolling of a metal strip, wherein the above-mentioned problems arising from residues on the surface of the metal strip are eliminated to a large extent. According to a second aspect of the present invention a process and a roll stand for cold rolling of a metal strip is to be provided where the deposition of ice or water within the roll stand and/or on the surface of the metal strip to be processed is avoided to a large extent. BRIEF SUMMARY OF THE INVENTION [0004] According to the present invention there is provided a process for cold rolling of a metal strip, wherein the metal strip passes through a nip between two counter-rotating rolls, driven in counter-rotation substantially at room temperature, wherein a cold and/or liquefied gas, preferably an inert gas, is blown into the area of the nip or roll gap. A roll stand according to the present invention comprises two counter-rotating rolls forming a nip or rolling gap and nozzle means for blowing a cold and/or liquefied gas, preferably an inert gas, through at least one orifice of said nozzle means into the area of the roll nip. Preferably, the temperature of the cold and/or liquefied gas is appreciably lower than room temperature. The term “cold and/or liquefied gas” as used herein relates to a cold fluid in the gaseous or liquid phase or in a phase mixture of gas and liquid. [0005] According to the invention the gas acts and as a cooling agent for cooling the metal strip during the cold rolling process and apparently as a lubricant for reducing friction between the rolls and the metal strip. The cooling effect is stronger if the gas is applied as a liquefied gas due to the larger specific heat of a liquid. According to the invention, the cooling agent, i.e. the gas, vaporizes during and after the cold rolling process without residuals on the surface of the metal strip. Accordingly, the present invention has the advantage that the cooling agent does not have to be removed in a separate process step after the cold rolling process. According to the present invention the gas creates a protective layer between the strip and the rolls. Preferably, the gas is an inert gas thereby avoiding oxidation of the surface of the metal strip. [0006] Due to the better cooling and apparent lubrication effect according to the present invention the metal strip virtually is free of cracks and pores and also the surface quality is better and more uniform. In particular, matte areas that cover the surface of the processed metal strip more or less completely in the conventional cold rolling process using a liquid lubricant are avoided according to the present invention. [0007] The nozzle means according to the invention preferably comprises a plurality of nozzles or orifices for blowing the cold and/or liquefied gas into the region of the nip that are arranged at regular intervals over the width of the metal strip. Preferably, the nozzles or orifices are positioned upstream of the roll nip. The nozzles or orifices may be positioned above and/or below the metal strip. The cold and/or liquefied gas may be blown into the area of the roll nip perpendicular to the metal strip or substantially tangential to the surface of the rolls. [0008] The inventors have observed that two new different types of surface defects occur, when a very cold gas, e.g. liquefied nitrogen gas is used. Namely, oval long matte areas and small matte points have been observed on the surface of the metal strip after the cold rolling process. The inventors have found out that some of these defects can be attributed to the creation of frozen atmospheric water vapor around the nozzles as well as around the feed line to the nozzles and to the water resulting from condensed atmospheric water vapor. Some of the defects observed could also be attributed to drops of liquefied gas, e.g. of liquefied nitrogen gas, falling onto the surface of the metal strip to be processed. [0009] In order to avoid these problems, the process for cold rolling of a metal strip according to the present invention may further comprise a step of shrouding or shielding the nozzle means at least near the orifice of the nozzle means from the ambient atmosphere for preventing the creation of water or ice near the orifice of the nozzle means due to frozen or condensed atmospheric water vapor. Accordingly, the creation of matte areas on the surface of the metal strip can be avoided. [0010] According to a first embodiment of the present invention the jets of cold and/or liquefied gas and/or the orifices of the nozzle system are shrouded or shielded by a flow a dry gas around the jet and/or the orifices during the cold rolling process. Thus, it can be avoided that water vapor from the ambient atmosphere enters the cooled region, e.g. the roll nip with the metal strip there between and/or the orifices of the nozzle system. Thus, the condensation or crystallization of the water vapor is eliminated. [0011] In principle any pure gas, i.e. not containing agents that could condense or crystallize to thereby cause the above-mentioned matte areas or surface defects, can be used according to the present invention. Preferably, the dry gas should be an inert gas. The process and roll stand according to the present invention may be simplified further, if the flow of dry gas is branched off from the flow of cold and/or liquefied gas, which flows to the orifices of the nozzle means and is used for cooling. [0012] The dry gas may be applied as a curtain of dry gas surrounding the jets of cold and/or liquefied gas emitted from the orifices of the nozzle means. Preferably, this curtain of dry gas shrouds the entire area both of the orifices of the nozzle means and of the roll nip including the metal strip being cooled by the cold and/or liquefied gas. [0013] Preferably, each feed line of an orifice for supplying the orifice of the nozzle system with the cold and/or liquefied gas is surrounded by a tube or a box-shaped structure through which the dry gas is blown towards the metal strip. Thus, the flow of dry gas is guided to flow substantially in parallel to the jet of cold and/or liquefied gas. Thus, it can be avoided that condensed water vapor or ice crystals from the ambient atmosphere fall onto the surface of the metal strip, where they would cause defects. A further advantage is that the amount of dry gas required for shrouding the orifices and/or jets of gas may be reduced substantially. A further advantage is that due to the steady flow of dry gas around the orifices of the nozzle system any deposition of ice or water on the orifices can be prevented completely. [0014] Preferably, the jets of cold and/or liquefied gas are emitted from the orifices of the nozzle means in the shape of a cone with the center in the middle of the respective orifice. Thus, a uniform distribution of gas in the area of the roll nip can be ensured. For a better shrouding the orifice may be located within the tube or box-shaped structure at a distance to the front face of the tube or box-shaped structure so that the cone does not intersect the tube or box-shaped structure on its way towards the metal strip. [0015] If the liquefied gas is fed to the orifices of the nozzle means, a part of the liquefied gas normally vaporizes. The gas bubbles thus created in the feed line causes pressure differences at the orifices or nozzle outlets and thus a pulsation of the gas jet emitted and of the liquefied gas supply. This pulsation is even amplified further within the feed line, because the gas of the bubbles has a smaller specific heat resulting in a less efficient cooling at certain regions within the feed line for liquefied gas. The pulsation of gas causes a non-uniform cooling effect in the area of the roll nip and may also dislodge ice crystals near the orifices or the nozzle means. Furthermore, the pulsation of gas in the feed line might also cause mechanical vibrations of the feed line that might also dislodge ice crystals near the orifices or the nozzle means or on the surface of the feed line. The inventors have observed, that these pulsation contribute to long oval matte areas on the surface of a metal strip. [0016] For the purpose of eliminating these problems, the dry gas flowing through the tube or box-shaped structure surrounding every feed line of the nozzle means is preferably derived directly from the flow of cold and/or liquefied gas for cooling. Thus, the exterior of the feed line and the orifices of the nozzle means can be cooled efficiently thereby reducing the above-mentioned two-phase flow of gas in the feed line. [0017] Preferably, the flow of gas through the tube or box-shaped structure is regulated by a control valve in order to obtain a constant cooling rate and a constant shrouding effect. Preferably this control valve is used simultaneously as a throttling means for expanding the cold and/or liquefied gas to thereby reduce its temperature. [0018] Thus, the temperature of the gas flowing through the tube or box-shaped structure may be lowered below the temperature of the gas in the feed line to thereby further eliminate the above-mentioned two-phase flow. Thus sub-cooling of the feed line can be achieved in an efficient manner. [0019] In order to further avoid the condensation or crystallization of water vapor from the ambient atmosphere heat exchange means or other heating means may be provided, preferably at the front end of the nozzle means. The heat exchange means may surround the tube or box-shaped structure, preferably only at a front portion. The fluid may flow through the heat exchange means. [0020] According to a second embodiment of the present invention a shrouding at least near the orifices of the nozzle means from ambient atmosphere is provided by a suitable mechanical structure for preventing the creation of condensed water or ice stemming from atmospheric water vapor near the orifices or nozzle outlets. [0021] According to this second embodiment shrouding may be provided by any mechanical structure sufficiently shielding the orifices or the nozzle means and/or the feed lines from ambient atmosphere. Such a shrouding may be provided by a single box surrounding all orifices or nozzle outlets and at least a portion of their respective feed lines for supplying cold and/or liquefied gas. Preferably, such a box has a front cover with openings aligned with the respective orifices to allow the flow of cold and/or liquefied gas towards the metal strip. Instead of a single box also a plurality of boxes may be provided, each for a respective orifice of the nozzle means. As an alternative, a tube may surround each orifice or nozzle outlet and at least a portion of the associated feed line. Thus, the orifices can be shrouded in a simple and cost efficient manner. [0022] The second embodiment of the present invention may be preferred, if a cold and/or liquefied gas at a moderate temperature as compared to room temperature is used for cooling, because at moderate temperatures the condensation and crystallization of atmospheric water vapor is used. An example of a liquefied gas used according to this second embodiment is carbon dioxide gas. This may be sufficient, e.g. for roll stands not used in continuous operation or with a relatively low throughput. [0023] Hereinafter, specific examples of preferred embodiments according to the present invention will be described. When read with reference to the Figures, further advantages, features and objects of the present invention will become aware to the skilled artisian. BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS [0024] [0024]FIG. 1 is a perspective view of a nozzle means according to a first embodiment of the present invention with partial section; [0025] [0025]FIG. 2 shows the perspective view of FIG. 1 with feed lines and shrouding lines highlighted; [0026] [0026]FIG. 3 is a sectional view showing a nozzle and a shroud tube; [0027] [0027]FIG. 4 is a perspective view of a nozzle means according to the first embodiment of this invention including a heat exchanger at a front part thereof; [0028] [0028]FIG. 5 is a perspective view of a second embodiment of a nozzle means according to the present invention; and [0029] [0029]FIG. 6 shows a roll stand in perspective view including a nozzle means according to the second embodiment of the present application. [0030] In the Figures, like reference numerals relate to identical or equivalent means or elements. DETAILED DESCRIPTION OF THE INVENTION [0031] [0031]FIG. 1 shows in perspective view a nozzle means 1 according to a first embodiment of the present invention. The nozzle means 1 comprises five nozzles 3 including a circular orifice 4 in the middle. A cone-shaped extension may be provided at the front part of each nozzle for guiding the flow of cold and/or liquefied gas emitted from the nozzles into a cone-shaped jet of cold and/or liquefied gas, as schematically shown in FIG. 6 (reference numeral 14 ). The nozzles 3 communicate via feed lines 9 with an insulated main feed line 7 . The nozzles 3 and the feed lines 9 are housed in the box 2 . A heat insulator may be provided within the box 2 , e.g. a resin or a foam of plastics like PU foam. The box 2 comprises a front cover 6 with circular openings respectively aligned with an orifice 4 or nozzle 3 so that the jets of cold and/or liquefied gas can propagate without hindrance towards the metal sheet or strip. [0032] In operation of the nozzle means, the main feed line 7 is supplied with cold and/or liquefied gas (arrow A). Examples for the gas include but are not limited to nitrogen, noble gas and carbon dioxide. Preferably the gas is an inert gas to thereby avoid oxidation of the metal strip. The gas may be fed via the main line 7 as a liquefied gas, a gas or a mixture of liquefied gas and gas. [0033] As can be seen in the partial section in the left hand part of FIG. 1, each nozzle 3 and at least the front part of each feed line 9 is surrounded by a shroud tube 12 for shrouding or shielding the area near the orifice of the nozzle 3 . The interior of the shroud tube 12 communicates with the respective feed line 9 via feed line 10 respectively provided with a control valve 11 . The control valve 11 is used to control the flow of cold and/or liquefied gas through the shroud tube 12 . [0034] As an alternative (not shown) each shroud tube 12 may communicate via a feed line and a control valve with a source of dry gas so that a different type of gas may be used for shrouding the jet of cold and/or liquefied gas emitted from the nozzles 3 . [0035] The outer surface of feed line 9 and the inner surface of shroud tube 12 may be provided with a reflective cooling. [0036] In operation, a jet of gas, e.g. a cone-shaped jet, is emitted from each nozzle 3 . The jet is surrounded by a curtain of dry gas emitted from the shroud tube 12 . Thus, ambient water vapor cannot condense or crystallize in or near the jet of gas used for cooling the metal strip. The dry gas leaves the shroud tube 12 substantially in parallel with the respective jet of gas used for cooling. The flow rate through the shroud tube 12 may be substantially lower than the flow rate of gas through the feed line 9 and nozzle 3 so that the shape of the gas jet emitted from each nozzle 3 is not disturbed by the dry gas. [0037] As can be seen in the partial section in the left hand part of FIG. 2, the control valve 11 may act simultaneously as a throttling valve where the gas flowing through the control valve 11 expands. Due to the gas expansion the temperature of the gas within the shroud tube 12 is lower than the temperature of the gas in the feed line 9 . Thus, both the nozzle 3 near its orifice 4 and the feed line 9 at its front portion, which is surrounded by the shroud tube 12 , are cooled, thereby preventing or substantially reducing two-phase flow of gas in the feed line 9 . Thus, any pulsation of the gas used for cooling within the feed line 9 can be prevented or substantially reduced. This results in a more uniform distribution of the gas on the metal strip. [0038] [0038]FIG. 3 shows a sectional view of the front portion of the feed line 9 including a shroud tube 12 for shrouding the region near the orifice of the nozzle 3 . FIG. 3 shows the feed line 9 of the left most or right most nozzle 3 of the embodiment according to FIGS. 1 and 2. The shroud tube projects from the front face of the nozzle 3 by a distance d. The distance d is chosen in accordance with the opening angle of the cone-shaped jet 14 emitted from the nozzle 3 so that the gas does not impinge on the interior surface of the shroud tube 12 . [0039] The nozzle 3 is connected by a suitable connecting means 13 with the feed line 9 . The interior of the shroud tube 12 communicates via the orifice 15 , the control valve 11 , and the feed line 10 with the feed line 9 so that a part of the gas in the feed line 9 is branched off towards the shroud tube 12 . [0040] The length L of the shroud tube 12 is chosen in accordance with the extent of cooling and reducing two-phase flow of gas in the feed line 9 . [0041] The nozzle 3 may provide a hollow cone, a solid cone or a flat cone of gas. Preferably, a flat cone is used. The opening angle of the cone 14 emitted from the nozzle 3 may be in the range between 45° to 110°, preferably near 80°. The diameter of the feed line 9 may be in the range between 10 and 20 mm, preferably 15 mm. The inner diameter of the shroud tube may be in the range between 20 and 55 mm, preferably 35 mm. The distance d may be in the range between +10 mm and −10 mm (+projecting/−retracted position), preferably −5 mm. Liquefied nitrogen may be supplied at a pressure between 0.5 atm to 16 atm, preferably 6 atm. The flow rate of liquefied nitrogen through each nozzle may be in the range between 10 l/h to 300 l/h, preferably 100 l/h to 150 l/h, with a flow rate through the shroud tube 12 , preferably in the range between 10 to 30 l/h. The skilled person may easily become aware of different parameter ranges depending on the specifications of the roll stand to be provided. [0042] [0042]FIG. 4 shows a modification of the first embodiment according to the present invention. In this modification a heat exchanger 24 is provided at the front part of the nozzle means 1 for controlling the temperature so that neither ice is deposited nor water condenses from atmospheric water vapor at the front part. For this purpose, the front part of the box 2 is formed as separate chamber 24 with an inlet port 25 and an outlet port 26 so that a fluid for heat exchange may flow through the chamber 24 around the shroud tubes 12 . If no shroud tubes are provided, as it is the case in the second embodiment of the present invention, the fluid may directly flow around the feed lines 9 instead. The flow rate of the fluid C entering the heat exchanger 24 or the flow rate of fluid D leaving the heat exchanger 24 may be controlled, e.g. by a control valve, so that a stable temperature can be obtained at the front part of the nozzle means 1 . Suitably, a temperature well above the dew point of ambient water vapor is chosen. [0043] [0043]FIG. 5 shows a second embodiment of the nozzle means 1 according to the present invention. According to the second embodiment no curtain of dry gas is provided for shrouding the orifices 4 and/or the jet of gas used for cooling. Instead, according to the second embodiment, the plurality of nozzles 3 and at least the front portion of the associated feed line 9 is housed in a box 2 including a front cover 6 with a plurality of openings in alignment with the respective nozzle 3 . Instead of providing a box-shaped structure 2 a skilled person in this field may easily become aware of other suitable shrouding structures. The relatively small cross-sectional area of the openings in the front cover 6 ensures that virtually no ambient air or ambient water vapor can enter the interior of the box 2 . In particular, this is the case when gas continuously flows out of the nozzles 3 , because the jet of gas results in a roller-shaped flow of ambient air away from the front cover 6 of the box 2 . [0044] In order to prevent a condensation or crystallization of water vapor within the box 2 or near the orifices 4 , the following measures may be taken: a hygroscopic agent may be provided within the box 2 ; the interior of the box 2 may be filled completely with a heat insulating material, e.g. a plastic foam like PU foam; a heating means may be provided at the front portion of the nozzle means 1 , e.g. on the inner surface of the front cover 6 , to heat this region to a temperature above the dew point; a heat exchanger, comparable to the heat exchanger 24 according to FIG. 4, may be provided. [0045] [0045]FIG. 6 shows a modification of the second embodiment according to the present invention. As shown in FIG. 6, four nozzles 3 are arranged side by side, directly communicating with a lower transverse feed line 21 that is symmetrically fed by the main feed line 7 . Heat insulation tubes 8 , 22 , 23 , and 12 surrounding the feed lines are provided. The front end of each tube 12 comprises an opening in alignment with the orifice of the respective nozzle 3 . [0046] [0046]FIG. 6 schematically also shows a roll stand including a nozzle means 1 according to the second embodiment. Two counter-rotating rolls 16 , at least one of them being driven, are provided for cold rolling the metal strip 18 fed into the direction B. In the roll nip 17 the metal strip or sheet 18 is reduced in thickness. [0047] In order to cool the metal strip 18 in the area of the nip portion and to simultaneously reduce the friction between the rolls 16 and the metal strip 18 , cool and/or liquefied gas, preferably liquefied gas, is blown into the nip region 17 by the nozzle means 1 . The nozzle means 1 may be provided on one or both sides of the rolls 16 . Furthermore, the nozzle means 1 may be provided above the metal strip 18 , as shown, and/or below the metal strip 18 . The gas may be blown into the nip region 17 in a direction substantially perpendicular to the metal strip 18 or in any other suitable direction, e.g. substantially tangential to the rolls 16 . Suitable choice of the nozzles 3 and the distances between the nozzles 3 ensures a uniform distribution of the gas used for cooling. [0048] While specific examples have been shown above, various modifications can be performed without leaving the scope of this invention, as will become apparent to a skilled person.
A process is set forth for cold rolling of a metal strip, wherein the metal strip passes through a nip between two counter-rotating rolls, driven in counter-rotation substantially at room temperature, wherein a cold and/or liquefied gas, preferably an inert gas, is blown into the area of the nip or roll gap. A roll stand according to the present invention comprises two counter-rotating rolls forming a nip or rolling gap and nozzle means for blowing a cold and/or liquefied gas, preferably an inert gas, through at least one orifice of said nozzle means into the area of the roll nip. Preferably, the temperature of the cold and/or liquefied gas is appreciably lower than room temperature.
1
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel control apparatus for an engine capable of supplying fuel corresponding to a quantity of air by suction the engine to arrive at an appropriate air/fuel rate. 2. Discussion of Background The conventional fuel control device of an engine measures an air quantity sucked in one stroke of the engine, as a whole, and supplies fuel to the engine, the quantity of which is in correspondence with the measured suction air quantity. Since the above mentioned conventional fuel control apparatus for an engine, measures the air quantity sucked in one stroke of the engine, as a whole, when the engine is accelerating or decelerating and the suction air quantity is changing rapidly, considerable time is required to detect the change of the suction air quantity, and as the result, the responsiveness of the control device is poor. SUMMARY OF THE INVENTION It is an object of the present invention to provide a fuel control apparatus for an engine capable of supplying fuel in accordance with the suction air quantity of the engine. According to an aspect of the present invention, there is provided a fuel control apparatus for an engine which comprises means for measuring an air quantity sucked into the engine and means for supplying fuel into the engine in correspondence with the air quantity sucked to the engine, said means for measuring the air quantity sucked into the engine measuring a predetermined number of times in one stroke of the engine, and said means for supplying fuel to the engine, supplying a quantity of fuel based on a ratio of the change of the measured value of the air quantity. BRIEF DESCRIPTION OF THE DRAWINGS A more complete appreciation of the invention and many of the attendant advantages thereof will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, wherein: FIG. 1 is a construction diagram showing an embodiment of a system to which a fuel control apparatus of an engine is applied, according to the present invention; FIG. 2 is a block diagram of this apparatus; FIGS. 3A to 3E are timing charts of this apparatus; and FIG. 4 to 6 are a flow charts which explain the operation of the apparatus. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawings, explanation will be given on the present invention. FIG. 1 is a construction diagram showing an embodiment of a system to which a fuel control apparatus of an engine is applied, according to the present invention. In FIG. 1, a numeral 1 signifies a throttle butterfly valve which changes the suction air quantity of an engine, 2, a Karman-type air-flow sensor (hereinafter AFS) which generates pulse signal corresponding to the suction air quantity, 3, a control unit which calculates and controls a drive time of an electromagnetic valve, mentioned later, by a crank angle signal and AFS 2, mentioned later, 4, electromagnetic valve, and the notation N signifies a crank angle signal. FIG. 2 is a block diagram of the control unit 3. In FIG. 2, a numeral 31 signifies a CPU, 32, a ROM, and 33 to 35, I/F which put interface between the various parts and the CPU 31. FIGS. 3A to 3E are timing charts of the abovementioned various signals in one stroke of the engine 1. As shown in FIG. 3C, when the opening of the throttle butterfly valve 1 changes and the suction air quantity increases, as shown in FIG. 3B, AFS 2 generates pulse signals having frequency number which is proportional to the suction air quantity. When the suction air quantity is small, a frequency number of the output pulse of AFS 2 is low. When the suction air quantity is large, the frequency number of the output pulse becomes high. On the other hand, the crank angle signal N, as shown in FIG. 3A, is a signal generated in mesh with the one stroke of the engine. One cycle of the crank angle signal N corresponds to one stroke of the engine. FIG. 3D shows the output pulse number P of AFS2. FIG. 3E shows a time between edges of the crank angle signal, T A and T B , of AFS2. Next, explanation will be given to the operation of the control unit 3 in the above embodiment, based on the flow charts of FIGS. 4 to 6. First of all, explanation will be given to the flow chart in FIG. 4. The program based on the flow charts is performed upon the trailing edge of the output pulse of AFS2. In Step 50, after the output pulse signal of AFS2 arrives, at the point of the tailing edge, P←P+1, that is, the output pulse number P of AFS2 is counted, and the operation is finished. The program based on the flow chart in FIG. 6 is performed at every predetermined time. At every predetermined time, in Step 70, the operation of T←T+1, is performed. This time T is utilized to measure the time between edges of a crank angle signal, T A and T B , mentioned later. Next, explanation will be given to the flow chart in FIG. 5. The program based on this flow chart is performed at every leading edge and every tailing edge of the crank angle signal N. First of all, in Step 60, a judgment is made on whether this program is performed by the leading edge of the crank angle signal. When a judgment is made in which the program is initiated by the tailing edge, in Step 60, the judgment is N. In Step 61, the output pulse number P of AFS2 is replaced with P A , the output time T of AFS2 is replaced with T A , and these two values are memorized in a memory. The operation goes to Step 62, in which the output pulse number and the output time T of AFS2 are cleared, and the operation is finished. Accordingly, the time required from the leading edge to the tailing edge of the crank angle signal is T A , a pulse number outputted from AFS2 during time T A , is P A . When a judgment is made in which this program is initiated by the rise of the crank angle signal, in Step 60, the judgment is Y. The operation goes to Step 63, where the output pulse number P of AFS2 and the times are memorized in the memory as P B and T B , respectively. In this case, the time between the tailing edge and the leading edge of the crank angle signal is T B , and the pulse number outputted by AFS2 in the time T B , is P B . Next, in Step 64, the suction air quantity A in one stroke of the engine is calculated by following equation. A←{(P.sub.A +P.sub.B) * K * ((P.sub.B * T.sub.A)/(P.sub.A * T.sub.B)} * K.sub.PC where K is a reflecting constant of an excessive information (P B * T A )/(P A * T B ), and K PC is a conversion constant for converting the output pulse number of AFS2, to the suction air quantity. In Step 65, the drive time T inj of the electromagnetic valve 4, is calculated by the following equation. T.sub.ing ←A * G where G is a constant for converting the suction air quantity A to a drive time of the electromagnetic valve 4. As stated above, the drive time T inj of the electromagnetic valve 4 is calculated, in Step 62, the values of the output pulse number P of AFS2, and the time T are cleared, and the operation is finished. As explained above, the ratio of change (P B * T A )/(P A * T B ) of the suction air quantity during the time between the leading edge and the tailing edge (during T A ) of the crank angle signal, and the suction air quantity during the time between the tailing edge and the leading edge (during T B ) of the crank angle signal, is reflected to the suction air quantity A in one stroke of the engine. This ratio of change is also reflected to the quantity of fuel. Furthermore, in this embodiment, explanation is given to the case in which the engine is accelerating and the suction quantity of the air is increasing. However, the same effect is obtained in the case in which the engine is decelerating and the suction air quantity is decreasing, by performing the same treatment as in the accelerating case. As mentioned before, in this invention, the suction air quantity is measured by "n" time of the one stroke of the engine, and the ratio of change of the suction air quantity is reflected to the fuel quantity which is supplied to the engine. Therefore, the fuel control apparatus of an engine with high responsiveness, is composed accurately and economically. Obviously, numerous modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described herein.
A fuel control apparatus for an engine which comprises means for measuring an air quantity sucked to the engine and means for supplying fuel to the engine in correspondence with the air quantity sucked to the engine, said means for measuring the air quantity sucked to the engine, measuring n times in one stroke of the engine, said means for supplying fuel to the engine, supplying fuel to the engine of which quantity is based on a ratio of change of the measured value of the air quantity.
5
BACKGROUND OF THE INVENTION The present invention relates to a safety device for use in gas burners, which continues to supply the gas during the presence of flame of combustion. Widely employed safety devices for preventing any possible danger that would be caused by the emission of unburned gases were composed of a thermocouple heated by the pilot flame, and an electromagnetic means energized by the electromotive force of the thermocouple to safely shut off the flow of gas when the flame has been extinguished. According to the above mentioned conventional safety valve devices, the safety valve is maintained at an open position while there is the output from the thermocouple, and the safety valve is restored to the close position when the output has extinguished, providing increased safety performance, economy in manufacturing cost and extended life. The thermocouple, however, has a thermal capacity and continues to produce the output due to the residual heat. Therefore, some period of time was required before the electromagnetic device was sufficiently de-energized. The duration of this time is dependent upon the force for maintaining the safety valve at the open position and the resilient force of a spring or the like for restoring the safety valve to the close position. If the duration of time is long, the flowing amount of the live gas increases after the flame has been extinguished, and an extended period of time is required before the safety valve returns to the close position. A dangerous condition will be presented if the next operation is taken place neglecting the above mentioned period of time. For example, the safety valve starts from the completely close position and supplies the main burner fuel after having supplied the pilot burner fuel, after having ignited the pilot flame and after having confirmed the burn of the pilot flame; the safety is maintained by performing the operation in the order mentioned. However, in case the operation is started again before the safety valve is returned to the completely close position, the aforesaid order of operation is neglected. Accordingly, a variety of contrivances have been devised such that the safety valve is returned to the completely close position before the operation takes place again. Two such gas valves are shown in the U.S. Paul Dietiker Pat. No. 3,877,475 issued Apr. 15, 1975 and the U.S. Paul Dietiker et al Pat. No. 3,973,576 issued Aug. 10, 1976. SUMMARY OF THE INVENTION The present invention relates to an improvement in a safety device which is so constructed that the next operation is not permitted to be effected until the electromotive force of the thermocouple is sufficiently reduced by the extinction of flame, or in other words, so constructed that the passage of gas is not allowed to be opened before the safety valve is restored to the completely close position. BRIEF DESCRIPTION OF DRAWING The invention is illustrated below with reference to an embodiment in conjunction with the drawings. FIG. 1 is a cross-sectional view showing the device of the present invention, FIG. 2 is a cross-sectional view showing the relation between the rotating position of the cock and the position of the first pin, FIG. 3, FIG. 4 and FIG. 5 are cross-sectional views showing the relations between the second pin and the reset shaft, FIG. 6 is a cross-sectional view when the device is looked down from the line X--X' of FIG. 1, FIG. 7 is a cross-sectional view when the device is looked down from the line Y--Y' of FIG. 1, and FIG. 8 is a drawing for illustrating the operating conditions of the operation member. DESCRIPTION OF THE INVENTION Referring to FIG. 1, a cock 2 is rotatably located at the lower portion 1 of a casing. The cock or main valve 2 has an upper chamber 3 and a communication port 4 communicated to said upper chamber 3. Owing to the rotation of the cock 2, the communication port 4 is allowed to successively face a pilot port 5 and a main port 6 thereby to supply the gas to the pilot flame of a pilot burner 40 and the main burner flame of a main burner 41. At the initial position (completely close position) of the cock 2, the communication port 4 is faced to the closed wall surface in the middle portion 11 of the casing; the gas is not supplied from the communication port 4. As the cock 2 is turned and the communication port 4 is faced to the pilot port 5, the gas is supplied to the pilot flame only via the pilot port 5. As the cock 2 is further turned so that the communication port 4 is faced to the main port 6, the gas is supplied to both the pilot flame and the main burner flame. A safety valve 16 is provided below the cock 2, whereby the upper chamber 3 and a low chamber 22 is separated by the safety valve 16. When a valve disk 24 of the safety valve 16 is closed, i.e. when the communication between the upper chamber 3 and the lower chamber 22 is interrupted by the valve disk 24, no gas is allowed to flow from a gas inlet port 13 to the upper chamber 3. The cock 2 is manually turned by turning a spindle 7 connected to a knob 23. A pin 9 attached to the spindle 7 is inserted in a groove 26 formed between the upper portion 10 of the casing and the middle portion 11 of the casing. The spindle 7 is capable of rotating the cock 2 as well as pressing a reset shaft 12 against the resilient force of the spring 8 in an axial direction. When the reset shaft 12 is compressed, the safety valve 16 moves downwards, so that the valve disk 24 opens the passage of gas. At this moment, if an electromagnetic device 14 has been energized by the electromotive force of the thermocouple 42, the valve disk 24 is maintained at the open position. First, in the initial state, the cock 2 is at the completely close position, and the gas is supplied from the gas inlet port 13 to the lower chamber 22. The valve disk 24, however, is brought into pressed contact with a valve seat 18 due to the resilient force of the spring 15 to interrupt the gas from flowing into the upper chamber 3. The valve disk 24 is composed of a resilient member such as rubber, and supported by a support plate 27 which is supported by a rod 28 at an engaging portion 25. To the support plate 27 is integrally attached a valve head 17 having a central recess 30. Next, if the knob 23 is pushed against the resilient force of the coil spring 8, the reset shaft 12 is moved downward to press the safety valve head 17. At this moment, if the valve disk 24 is opened, the gas is admitted to flow from the inlet port 13 into the upper chamber 3 through the lower chamber 22. The second operation consists of turning the knob 23 by 90°. At this moment, the communication port 4 of the cock 2 is faced to the pilot port 5 to supply the gas to the pilot port. Here, if the pilot port is ignited, the electromagnetic device 14 is energized by the electromotive force of the thermocouple. When energized, the electromagnetic device 14 containing a pole piece and a coil for holding the safety valve 16 at the open position, locks the position of the rod 28. When the safety valve 16 is pushed by the reset shaft 12, the rod 28 moves downwards toward the interior of the electromagnetic device 14; the position of the rod 28, therefore, is locked by the energized electromagnetic device 14. The third operation consists of releasing the knob 23 from being pressed. The safety valve 16, at this moment, has been locked by the electromagnetic device 14 and is maintained in an open position. FIG. 2 shows positions for locking the pin 9 attached to the spindle 7. The diagram (a) shows the completely close position of the cock 2, i.e. the position of the pin 9 in the initial state. In the diagram (a), the pin 9 is allowed to move downward by a depth a. This movement is effected by pushing the knob 23; the pin 9 is downward moved by the depth a when the safety valve 16 acquires the open position. The second operation consists of turning the knob 23 by 90°. At this moment, the gas is supplied to the pilot flame. The third operation consists of releasing the knob 23 from being pressed when the safety valve 16 is maintained at the open position after the pilot flame has been established. At this moment, the pin 9 is returned upwards by a depth b to acquire a position shown in the diagram (b). In the fourth operation, the knob 23 is further turned by 90°, whereby the gas is supplied to the main burner flame, and the pin 9 is fitted to the groove 26 as shown in the diagram (c). Referring to FIG. 1, a second pin 19 is movably supported on an inclined surface 20 formed on the lower portion 1 of the casing and the upper surface 29 of valve 16. The pin 19 consists of a round rod and is allowed to move along the inclined surface 20 as shown in FIG. 3, FIG. 4 and FIG. 5. FIG. 3 shows a position of the pin 19 in the initial state. The pin 19 is held in place between the inclined surface 20 and the upper surface 29 of safety valve head 17. If the knob 23 is pushed in the first operation so that the reset shaft 12 pushes the safety valve head 17, the safety valve head 17 is driven downward and, instead, the reset shaft 12 comes into contact with the pin 19. The pin 19 at this moment is interposed between the reset shaft 12 and the inclined surface 22 and remains in the initial position. In the third operation, the knob 23 is released from the pressed state and the reset shaft 12 is allowed to return to the upper direction. At this moment, the lower end of the reset shaft 12 comes into contact with the pin 19 as shown in FIG. 4, and the pin 19 is located at a position sandwiched between the inclined surface 20 and the reset shaft 12. While the combustion is taking place with the safety valve 16 being opened, the pin 19 remains located at a position shown in FIG. 4. When the flame is extinguished by turning knob 23 to the initial position so pin 9 is as shown in FIG. 2(a), only the reset shaft 12 returns to the initial position. When the restoration operation of the safety valve 16 to the close position is delayed, the pin 19 falls from the inclined surface 20 onto the groove 21 as shown in FIG. 5. At this moment, even if the knob 23 is pushed, the movement of the reset shaft 12 toward the axial direction is interrupted by the pin 19; the reset shaft is not allowed to turn as pin 9 remains in groove or detent 33. To stop the combustion of the pilot flame and the main burner flame, the operation should be carried out in the following manner. That is, operate the knob 23 to turn the cock 2. At this moment, the pin 9 moves from the position of diagram (c) of FIG. 2 to the position of diagram (b) and comes into contact with the wall 31. The gas is interrupted from being supplied to the main burner flame but is supplied to the pilot flame only. The knob 23 is then turned while being pushed, and the pressing force is released from the knob 23 when it has come into contact with the wall 32 as shown in the diagram (a) of FIG. 2. The pilot flame is extinguished to acquire the initial state. To start the combustion, the knob should be operated from the close position to the open position via the pilot flame position as indicated by arrows in FIG. 8. To stop the combustion, the knob should be operated in reverse order as indicated by arrows of opposite direction as shown in FIG. 8. At the close position, the gas is supplied neither to the pilot flame nor to the main burner flame. At the pilot flame position, the gas is supplied to the pilot flame only, and at the open position, the gas is supplied to both the pilot flame and the main burner flame. The supply of gas must be quickly interrupted in case the flame is extinguished in either the pilot flame position or the open position. In this case, although the electromotive force of the thermocouple may diminish, the residual heat retards the closure of the safety valve 16 after the flame has been extinguished. When the resilient force of the return spring 15 has overcome the diminishing electromotive force of the thermocouple, the safety valve 16 is closed, and the valve disk 24 comes into pressed contact with the valve seat 18. If the flame is extinguished and the operation is effected again before the safety valve 16 is completely closed, the turn of the cock from the close position toward the pilot flame position or the open position permits the live gas to flow out. Such a repetitive operation could be prevented relying upon the discrimination of a person who operates or by observing the flame port. Such methods, however, lack reliability and, in addition, it often will be difficult to reliably observe the flame port. According to the present invention, the safety device is so constructed that if the safety valve is once operated, the next operation is never allowed to be carried out unless the safety valve is completely restored to the close position, thereby to enchance the safety performance. The features and functions of the device according to the present invention are mentioned below. DESCRIPTION OF THE OPERATION OF THE INVENTION Prior to starting the operation, the device of the invention acquires the position shown in FIG. 1. The first operation consists of pushing the knob 23 to depress the safety valve head 17 via the spindle 7 and the reset shaft 12, so that the valve disk 24 acquires the open position. The second operation consists of turning the knob 23 by 90° while it is being pushed, so that the cock 2 comes to the position of pilot port to supply the gas to the pilot port. The pilot port is then ignited, and when the electromagnetic device 14 is energized by the electromotive force of the thermocouple, the knob 23 is released from the pushed state. At this moment, the knob 23 is allowed to return upwards by a distance b. In FIG. 2, the position of the knob 23 is indicated by the position of the first pin 9 attached to the spindle 7. As the knob 23 is further turned by 90°, the cock 2 acquires the open position whereby the pilot flame and the main burner flame are allowed to burn. In the aforesaid operation, the second pin 19 remains in the initial position. If now the flame is extinguished, the electromagnetic device 14 is de-energized being delayed by some periods of time. The safety valve 16 remains open during this delay time, and at this time, the knob 23 is returned to the initial position, i.e. returned to the close position shown in the diagram (a) of FIG. 2. At this moment, as shown in FIG. 5, the second pin 19 of which right side is not supported by the reset shaft 12 is allowed to fall from the inclined surface 20 onto the groove 21. Therefore, even if the knob 23 is pushed, the downward motion of the reset shaft 12 is restricted by the pin 19, whereby the knob 23 is not allowed to be turned. Then, after the delay time has passed, the safety valve 16 returns to the close position whereby an inclined edge portion 29 (inclined in a direction opposite to the incline surface 20) of the safety valve head 17 so works that the second pin 19 is pushed up again onto the inclined surface 20; the second pin 19 returns to the initial position. This allows the operation to be effected again. That is, unless the safety valve 16 is restored to the close position, the reset shaft 12 comes into contact with the second pin 19 and is allowed to move no more in the axial direction. If illustrated with reference to the diagram (a) of FIG. 2, the first pin 9 cannot escape from the groove 33 whereby the spindle 7 and the knob 23 are prevented from being turned. As mentioned above, according to the device of the present invention for use in gas burners that will be operated in the order of from the close position to the open position, the second or subsequent operation from the close position is now allowed to be effected unless the safety valve is restored to the inoperative position (close position). The setup of the present invention comprises the operation member (knob 23, spindle 7, reset shaft 12) which moves in the axial direction and rotates with the axis as a center, a holder device (electromagnetic device 14) for holding the safety valve 16 in the operative position when it is moved to the operative position by the operation member, means (thermocouple device not diagrammatized) for energizing the holder device after having confirmed the presence of burning flame, and the cock 2 provided on the gas flow-out side of the safety valve 16 to turn in the same direction as the operation member when said operation member is turned, wherein in order to inhibit the operation from the close position toward the open position unless the safety valve 16 is restored to the inoperative position after the combustion flame has been extinguished, the movement of the operation member in the axial direction is prevented by pin 19 so that said operation member is not rotated but prevented by pin 9, so that the gas is prevented from flowing to the pilot flame or to the main burner flame.
A safety gas valve for gas burners for providing a "super safe" operation wherein upon the main valve being turned to an off position and the safety valve is held in an operative position by the residual heat of the thermocouple, means is provided for preventing the manual member for opening the main valve until the safety valve returns to the inoperative position.
5
BACKGROUND OF THE INVENTION The present invention relates to conveyor systems and, more particularly, to speed controlled infeed conveyor systems. In conveyor systems employing a conveyor belt that delivers a column of edge-stacked articles (for example, cookies or crackers) onto an infeed apron or chute of a product handling machine, a certain axial pressure is necessary within the column to hold the articles in the vertical on-edge position. The axial pressure is a function of the relationship between the speed of the conveyor and the rate at which the articles are removed from the apron or chute by the product handling device. When the conveyor is trying to deliver articles to its output end at a rate that exceeds the actual removal rate, the product pressure increases. As the pressure builds, the column of articles will arch upwardly. If the pressure continues to build, the arch eventually will collapse. Many product pieces will be strewn on the floor and others will fall back onto the conveying surface in random orientation and will jam the system. Where the edge-stacked articles are of uniform thickness and that thickness does not vary from batch to batch of the product, the product pressure can be held at a constant value simply by setting the conveyor speed to correspond to the speed of operation of the product handling device. However, in the manufacturing of crackers and cookies, the thickness does vary from batch to batch. Such variations are due to slight changes in the character of the ingredients, in the quantities used, or in the bake time or temperature. These changes are minute but when hundreds of crackers are stacked on edge, the cumulative effect becomes significant. The speed of the conveyor systems transporting the baked goods from the ovens to the packaging machines, is geared to that of the conveyor that carries the pieces through the oven. Whether the baked goods of a particular batch are thicker or thinner than normal, they flow out of the oven at the same rate. But a specific number of thick crackers produce a longer column than the same number of thin crackers, and thereby product pressure is effected. SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide an improved speed controlled infeed conveyor system which automatically adjusts the conveyor speed in response to changes in axial product pressure. The object of the invention is accomplished by providing a motor driven infeed conveyor feeding a column of articles onto a downwardly curved chute to an intermittent product receiving device, a photoelectric arrangement for producing an electrical signal proportioned to the displacement of the column from the curved chute in response to product pressure, and speed control apparatus responsive to the electrical signal for adjusting the speed of the input conveyor. BRIEF DESCRIPTION OF THE DRAWINGS A preferred embodiment of the invention has been chosen for purposes of illustration and description and are shown in the accompanying drawings, forming a part of the specification, wherein: FIG. 1 is a schematic side elevational view of a conveyor system according to the present invention showing the position of the product column under a low product pressure condition, FIG. 2 is a schematic view similar to FIG. 1 showing the position of the product column under a high product pressure condition, FIG. 3 is a schematic plan view of the system of FIGS. 1 and 2 showing the speed control apparatus for adjusting the speed of the input conveyor in response to changes in product pressure. DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawings in detail, there is shown a speed controlled infeed conveyor system according to the present invention in which an infeed conveyor 10 delivers a column of edge-stacked crackers P to a downwardly arcing chute 11. The crackers are intermittently removed from the bottom of the chute 11 by a package loading device 12. The loading device includes a reciprocating arm (not shown) which removes a number of crackers from the column on each stroke. The device 12 may be designed so that different numbers of crackers are removed on subsequent strokes. Loading devices of this general type are shown in U.S. Pat. Nos. 3,338,370 and 3,451,563. As seen in FIG. 1, when the axial product pressure is low, the edges of the crackers P are in engagement with the chute 11 throughout its length. As the axial product pressure increases, the column of crackers bows outwardly away from the chute as shown in FIG. 2. The chute is provided with side rails 14 to confine the column against lateral movement. A light source 15 directs a beam of light perpendicular to the direction of the bowing movement of the column so that the column of crackers progressively intercepts the column of light as it bows outwardly. A photoelectric device 16 is positioned to receive the light which is reflected from the bowing column. As the column progressively intercepts the beam of light, the amount of light reflected increases proportionately. The photoelectric device 16 produces an electrical signal which varies in amplitude in proportion to the light level it receives. Since the loading device 12 works in an intermittent manner and the input conveyor 10 operates continuously, the axial product pressure builds between product removing strokes and suddenly decreases when a group of articles is removed. The output of the amplifier 17 (E 1 ) has a jagged waveform representing the instantaneous changes in the product pressure. This signal is passed through a filter circuit 19 to average out the short term signal variations and produce an output that represents the relationship of the rate of product input to the average rate of product output. The filtered signal (E 2 ) is fed into a summing amplifier 20 where it is added to a feed back signal E 3 which varies with the speed of the conveyor 10. The summing amplifier compares the sum of E 2 and E 3 with a reference voltage E 4 and produces an error signal when E 2 +E 3 does not equal E 4 . This error signal is used to adjust a power amplifier 21 that controls an eddy current clutch 22 in the drive mechanism for the infeed conveyor 10. The conveyor 10 is driven by a roller 24 mounted on a shaft 25 that is connected to the output of the clutch 22. A constant speed motor 26 is connected to the input of the clutch 22 by a shaft 27. A tachometer 29 driven from the shaft 25 through gears 30 and 31 provides the feed back signal E 3 . The eddy current clutch consists of a circular plate 32 and a cup-shaped armature 34 which receives the plate 32. The armature is connected to the input shaft 27 and the plate is connected to the output shaft 25. The power amplifier 21 feeds a coil 35 in the clutch to generate a magnetic field. This field produces a magnetic circuit in the armature 34 which is completed by the plate 32. As the armature 34 rotates, the magnetic link between the plate and the armature produces a rotational force in the plate which varies in proportion to the output of the power amplifier 21. The amplifier 21 is biased so that, when there is no error signal generated by the summing amplifier, the clutch 22 drives the conveyor 10 at a speed which produces sufficient product pressure to lift the column of crackers on the chute 11 to a position partially intercepting the column of light from the source 15. A potentiometer 36 connected to the summing amplifier is used to set the value of E 4 to equal the sum of the feedback signal E 3 and the E 2 signal produced by that degree of bowing of the column. The system will now automatically respond to any further outward bowing of the column by producing a negative error signal to slow the conveyor 10. Likewise, any decrease in the bow of the column will product a positive error signal to speed up the conveyor. It will be seen from the foregoing that the present invention provides an improved speed controlled infeed conveyor system which automatically adjusts the conveyor speed in response to changes in axial product pressure.
A speed controlled conveyor system in which the motor driving an input conveyor is speed regulated to control the axial product pressure. This pressure is measured by the outward bowing of the column of articles as it moves along a downwardly curving chute connecting the conveyor and the loading device. A photocell arrangement measures the degree of displacement of the column and transmits a corrective electrical signal to a motor speed control device.
8
REFERENCE TO RELATED APPLICATIONS This application claims the benefit of U.S. Provisional Patent Application No. 60/199565 filed Apr. 25, 2000. FIELD OF THE INVENTION The present invention relates to a method for reducing the viscosity of crude oils and crude oil residuum by mineral acid enhanced thermal treatment of crude oil or crude oil residuum. The product from the combination of acid and thermal treatment process affords oil with a substantially lower viscosity than the starting oil or product oil derived from thermal treatment without acid addition. Thus, the instant process provides an improved visbreaking method and can be utilized as an upgrading process in pipeline transportation, or to reduce the viscosity of a water-in-oil emulsion used in enhanced oil recovery (EOR) operations. BACKGROUND OF THE INVENTION Technologies for viscosity reduction of heavy crude oils and resids are of importance to the upstream and downstream petroleum businesses respectively. In downstream refining operations, visbreaking and hydro-visbreaking (visbreaking with hydrogen addition) of resids are known in the art and practiced commercially. In the upstream production operations, crude oil dilution with gas condensate and emulsification technologies using caustic and water are some of the commonly practiced art in pipeline transportation of heavy oils e.g., bitumen. Moreover, viscosity reduction of heavy crude oils can play a role in new upstream technology related to recovering hydrocarbons from subterranean formations using enhanced oil recovery methods. There is a continuing need in the oil industry for technologies and technology improvements relating to viscosity reduction of crude oils and resids. The depletion of reserves containing high quality crude oil, and the accompanying rise in costs of high quality crude oil has producers and refiners of petroleum looking to heavy crude oil reserves as a source for petroleum. There are many untapped heavy crude oil reserves in a number of countries including Venezuela, Chad, Russia, the United States and elsewhere. However, these heavy crude oils, because of their high viscosity and poor flow properties, pose significant challenges to producers, transporters and refiners of oil. Heavy crude oils are often difficult if not impossible to extract from subterranean formations in an efficient and cost-effective manner. Further, even when the heavy crude is extracted, the poor flow characteristics of the crude oil present additional complications in pumping, transporting and refining the crude oil. Processes have been developed to aid in extracting the heavy crude from underground reservoirs. For instance, a new process has recently been developed which aids in extracting heavy crude oil from a subterranean formation, which uses solids-stabilized emulsions as a driver fluid or as a barrier fluid to help recover hydrocarbons from the subterranean formation. These methods are generally discussed in U.S. Pat. Nos. 5,927,404, 5,910,467, 5,855,243, and 6,068,054. U.S. Pat. No. 5,927,404 describes a method for using the novel solids-stabilized emulsion as a drive fluid to displace hydrocarbons for enhanced oil recovery. U.S. Pat. No. 5,855,243 claims a similar method for using a solids-stabilized emulsion, whose viscosity is reduced by the addition of a gas, as a drive fluid. U.S. Pat. No. 5,910,467 claims the novel solids-stabilized emulsion described in U.S. Pat. No. 5,855,243. U.S. Pat. No. 6,068,054 describes a method for using the novel solids-stabilized emulsion as a barrier for diverting the flow of fluids in the formation. In a solids-stabilized emulsion, the solid particles interact with the surface-active components in the water and crude oil to enhance the stability of the emulsion. The process is simple in that the emulsion is made by simply mixing oil, typically crude oil from the reservoir itself, with micron or sub-micron sized solid particles and mixing with water or brine until the emulsion is formed. The process is also cheap in that all of these materials should be readily available at the reservoir site. Solids-stabilized water-in-oil emulsions have a viscosity that is greater than that of the crude oil to be recovered, and as such, can serve as an effective drive fluid to displace the crude oil to be recovered, such as described in U.S. Pat. Nos. 5,927,404, and 5,855,243. The solids-stabilized water-in-oil emulsions can also be used as a barrier fluid, to fill in subterranean zones of high rock permeability, or “thief zones.” When drive fluid is injected into a reservoir, the injected drive fluid may channel through these zones to producing wells, leaving oil in other zones relatively unrecovered. A high viscosity barrier fluid, such as the solids-stabilized water-in-oil emulsion, can be used to fill these “thief zones” to divert pressure energy into displacing oil from adjacent lower-permeability zones. However, sometimes the solids-stabilized water-in-oil emulsion is too viscous to be injected or is too viscous to otherwise be efficiently used as a drive or barrier fluid. Therefore, there is a need to be able to reduce the viscosity of the emulsion to obtain the optimum rheological properties for the type of enhanced oil recovery method used and for the particular type and viscosity of crude oil to be recovered. Viscosity reduction of heavy oils is also important for downstream operations. Transporters and refiners of heavy crude oil have developed different techniques to reduce the viscosity of heavy crude oils to improve its pumpability. Commonly practiced methods include diluting the crude oil with gas condensate and emulsification with caustic and water. Thermally treating crude oil to reduce its viscosity is also well known in the art. Thermal techniques for visbreaking and hydro-visbreaking are practiced commercially. The prior art in the area of thermal treatment or additive enhanced visbreaking of hydrocarbons teach methods for improving the quality, or reducing the viscosity, of crude oils, crude oil distillates or residuum by several different methods. For example, several references teach the use of additives such as the use of free radical initiators (U.S. Pat. No. 4,298,455), thiol compounds and aromatic hydrogen donors (EP 175511), free radical acceptors (U.S. Pat. No 3,707,459), and hydrogen donor solvent (U.S. Pat. No 4,592,830). Other art teaches the use of specific catalysts such as low acidity zeolite catalysts (U.S. Pat. No. 4,411,770) and molybdenum catalysts, ammonium sulfide and water (U.S. Pat. No. 4659453). Other references teach upgrading of petroleum resids and heavy oils (Murray R. Gray, Marcel Dekker, 1994, pp.239-243) and thermal decomposition of naphthenic acids (U.S. Pat. No. 5,820,750). A common thread that knits the various methods previously described is a need to obtain optimum viscosity reduction in oil. SUMMARY OF THE INVENTION It is this aspect of enhancing viscosity reduction that this invention addresses. Provided is a method of reducing the viscosity of oil or a water-in-oil emulsion by an acid enhanced thermal treatment process. The product from the acid enhanced thermal treatment process has a substantially lower viscosity than the untreated oil or the untreated water-in-oil emulsion, respectively. An embodiment of the invention is directed to a method for decreasing the viscosity of crude oils and residuum comprising the steps of: (a) contacting the crude oil or residuum with an effective amount of an acid consisting essentially of acid, (b) heating said crude oil or crude oil residuum and said acid at a temperature and for a time and at a pressure sufficient to decrease the viscosity of said crude oil or residuum. As used herein, crude oil residuum is defined as residual crude oil obtained from atmospheric or vacuum distillation. As used herein, the process comprises, consists and consists essentially of the steps herein described. Another embodiment of the process is directed to a thermal visbreaking method for reducing the viscosity of crude oils and crude oil residuum by thermally treating the oils and residuum wherein the improvement comprises contacting the crude oil or residuum with an effective amount of an acid consisting essentially of or consisting of acid and heating said crude oil or residuum and said acid at a temperature and for a time and at a pressure sufficient to decrease the viscosity of said crude oil or residuum. The invention is also directed to a crude oil or crude residuum having decreased viscosity prepared by (a) contacting the crude oil or residuum with an effective amount of an acid consisting essentially of acid, (b) heating said crude oil or residuum and said acid at a temperature and for a time and at a pressure sufficient to decrease the viscosity of said crude oil or residuum. Another embodiment of the invention is directed to a method of preparing a water-in-oil emulsion with a decreased viscosity comprising the steps of: (a) contacting the oil with acid, (b) heating said oil and said acid at a temperature and for a time and at a pressure sufficient to decrease the viscosity of said oil, and (c) adding water and mixing until said water-in-oil emulsion is formed. A solids-stabilized emulsion having a reduced viscosity may also be made using this method by adding solid particles to the oil after the step of heating the acid treated oil (step b), but before emulsification by adding water and mixing (step c). BRIEF DESCRIPTION OF THE FIGURES FIGS. 1A and 1B are viscosity versus shear rate plots for the untreated and thermally treated T and K crude oils at 25° C. The X axis is Shear rate (sec −1 ) and the Y axis is viscosity (cP). The line with diamonds is the untreated crude oil. The line with squares is heat treatment alone. The line with triangles is the acidic heat treatment combination described herein. FIGS. 2A and 2B depict viscosity versus temperature plots for the untreated and thermally treated T and K crude oils. The X axis is temperature 1000/T(1/K) and the Y axis is viscosity (cp.) expressed as ln(vis)@0.204 sec −1 . The line with diamonds is the untreated crude oil. The line with squares is heat treatment alone. The line with triangles is the acidic heat treatment combination described herein. FIG. 3 depicts viscosity versus shear rate plots for a heavy vacuum resid at 60° C. The X axis is Shear rate (sec −1 ) and the Y axis is viscosity (cP). The line with diamonds is heat treatment alone. The line with squares is the acidic heat treatment combination described herein. FIG. 4 depicts viscosity versus temperature plots for a heavy vacuum resid. The X axis is temperature 1000/T(1/K) and the Y axis is viscosity (cP) expressed as ln(vis)@9.6 sec −1 . The line with diamonds is heat treatment alone. The line with squares is the acidic heat treatment combination described herein. DETAILED DESCRIPTION OF THE INVENTION According to the invention, there is provided an improved method for viscosity reduction of crude oils and crude oil residuum. An acid is added to the crude or residuum followed by thermal treatment at temperatures of about 250 to about 450° C. at about 30 to about 300 psi for about 0.25 to 6 hours in an inert environment. Typically, the amount of acid added will be about 10 to about 1000 ppm, preferably about 20 to 100 ppm, based on the amount of crude oil or crude oil residuum. Preferably, the acid utilized in the contacting step will not contain other components not inherent in the acid itself or not present in the acid as impurities. Thus, preferably, the acid will consist essentially of or consist of acid. In the instant invention, one skilled in the art can choose process conditions to retain or degrade naphthenic acids in addition to reducing the viscosity of the crude. For example, to degrade the naphthenic acids a purge gas is used as disclosed in U.S. Pat. No. 5,820,750. Any inert purge gas (a gas non-reactive in the process) may be used. For example nitrogen, argon, etc. Interestingly, the instant invention allows for acid addition to crude oils which are high in naphthenic acids to achieve viscosity reduction. Such an addition of acid to acidic crude oil is counter intuitive since refiners are continuously looking for methods which reduce the amount of acid in crude oils and residuum. The types of acids which can be utilized in the instant invention include mineral acids such as sulfuric acid, hydrochloric acid and perchloric acid. Organic acids like acetic, para-toluene sulfonic, alkyl toluene sulfonic acids, mono di and trialkyl phosphoric acids, organic mono or di carboxylic acids, formic, C3 to C16 organic carboxylic acids, succinic acid, & low molecular weight petroleum naphthenic acid are also effective in this invention. Mixtures of mineral acids, mixtures of organic acids or combinations of mineral and organic acids may be used to produce the same effect. The preferred mineral acid is sulfuric or hydrochloric acid. The preferred organic acid is acetic acid. Nitric acid should be avoided since it could potentially form an explosive mixture. Reaction time, temperature and pressure collectively define process severity. One ordinarily skilled in the art can choose process severity within the preferred ranges to produce the desired level of viscosity decrease. Though not wishing to be bound, applicants believe that the acid enhanced thermal treatment alters the molecular aggregation properties of associating chemical species. Viscosity Reduction of a Water-in-Oil Emulsion Using Acid Enhanced Thermal Treatment The previously described method for reducing the viscosity of oil can be used to make a water-in-oil emulsion or a solids-stabilized water-in-oil emulsion with a reduced viscosity. The viscosity of the oil is reduced by the method previously described, prior to using the oil to make the emulsion. Though any decrease in the viscosity of the oil can be beneficial, preferably the viscosity will be decreased by at least about 2 to 30 times that of the viscosity of the oil prior to the treatment described herein. To make a water-in-oil emulsion with a reduced viscosity using this method, water or brine is added to the acid enhanced thermally treated oil. The water or brine is added in small aliquots or continuously with mixing, preferably at a rate of about 500 to about 12000 rpm, for a time sufficient to disperse the water as small droplets in the continuous oil phase, thereby forming the emulsion. The amount of water in the emulsion water can range from 40 to 80 wt %, preferably 50 to 65 wt %, and more preferably 60 wt %. Preferably, formation water is used to make the emulsion, however, fresh water can also be used and the ion concentration adjusted as needed to help stabilize the emulsion under formation conditions. The resulting emulsion will have a substantially lower viscosity than an emulsion made with an untreated oil, or an oil subjected only to thermal treatment. A solids-stabilized water-in-oil emulsion with a reduced viscosity can also be made using the acid enhanced thermal treatment process described above. The solids particles may be added to the oil before or after the acid addition and thermal treatment step, but should be added before adding water and emulsifying. However note that if the solid particles are present during the thermal treatment step, the solid particles have the potential for fouling the process equipment, and this issue needs to be addressed to practice this embodiment. Accordingly, it is preferred to add the solids particles to the oil after the acid and thermal treatment steps. The solid particles preferably should be hydrophobic in nature. A hydrophobic silica, sold under the trade name Aerosil® R 972 (product of DeGussa Corp.) has been found to be an effective solid particulate material for a number of different oils. Other hydrophobic (or oleophilic) solids can also be used, for example, divided and oil-wetted bentonite clays, kaolinite clays, organophilic clays or carbonaceous asphaltenic solids. The individual solid particle size should be sufficiently small to provide adequate surface area coverage of the internal droplet phase. If the emulsion is to be used in a porous subterranean formation, the average particle size should be smaller than the average diameter of pore throats in the porous subterranean formation. The solid particles may be spherical in shape, or non-spherical in shape. If spherical in shape, the solid particles should preferably have an average size of about five microns or less in diameter, more preferably about two microns or less, even more preferably about one micron or less and most preferably, 100 nanometers or less. If the solid particles are non-spherical in shape, they should preferably have an average size of about 200 square micron total surface area, more preferably about twenty square microns or less, even more preferably about ten square microns or less and most preferably, one square micron or less. The solid particles must also remain undissolved in both the oil and water phase of the emulsion under the formation conditions. The preferred treat rate of solids is 0.05 to 0.25 wt % based upon the weight of oil. The resulting water-in-oil emulsion or solids-stabilized water-in-oil emulsion's pH can be adjusted by adding a calculated amount of weak aqueous base to the emulsion for a time sufficient to raise the pH to the desired level. If the pH of the emulsion is too low (less than 4), it may be desirable to adjust the emulsion's pH to the 5 to 7 range. Adjusting the pH is optional as in some cases it is desirable to inject an acidic emulsion and allow the reservoir formation to buffer the emulsion to the reservoir alkalinity. Ammonium hydroxide is the preferred base for pH adjustment. Stronger bases like sodium hydroxide, potassium hydroxide and calcium oxide have a negative effect on emulsion stability. One possible explanation for this effect is that strong bases tend to invert the emulsion, i.e. convert the water-in-oil emulsion to an oil-in-water emulsion. Such an inversion is undesirable for the purposes of this invention. The water-in-oil emulsion or the solids-stabilized water-in-oil emulsion can be used in a wide range of enhanced oil recovery applications. One typical application is using such an emulsion for displacing oil from a subterranean formation, i.e. using the emulsion as a drive fluid. The emulsion is prepared, as described above, and then injected into the subterranean formation, typically, but not necessarily through an injection well. The emulsion, which is injected under pressure, is used to displace the oil in the formation towards a well, typically a production well, for recovery. Another application is for using the emulsion as a barrier fluid to divert the flow of hydrocarbons in a subterranean formation. Again, the emulsion is prepared and then injected into the subterranean formation. The emulsion is used fill “thief zones” or to serve as a horizontal barrier to prevent coning of water or gas. As previously explained, “thief zones” and coning events will reduce the efficiency of enhanced oil recovery operations. The present invention has been described in connection with its preferred embodiments. However persons skilled in the art will recognize that many modifications, alterations, and variations to the invention are possible without departing from the true scope of the invention. Accordingly, all such modifications, alterations, and variations shall be deemed to be included in this invention, as defined by the appended claims. The following examples are included herein for illustrative purposes and are not meant to be limiting. EXAMPLES In a typical experiment 200 g of the crude oil was placed in a Parr autoclave and 10 to 50 ppm of sulfuric acid was added to the crude oil and mixed for 10 minutes at 25° C. The sulfuric acid treated crude oil was purged with an inert gas like nitrogen for 30 minutes, autoclave sealed under nitrogen and the contents heated to 360° C. for 2 to 6 hours at pressures ranging from 90 to 280 psi. It is to be noted that thermal treatment was conducted in the absence of a continuous sweep of inert gas. In the absence of an inert sweep gas, viscosity reduction without significant TAN reduction is expected. After completion of experiment, the treated crude was analyzed for a) total acid number (TAN) and molecular weight distribution of the naphthenic acids b) heptane insolubles c) toluene equivalence and viscosity determined at 20, 25, 30, 35 and 40° C. in a shear range of 0.1 to 2.5 sec −1 . Results Examples 1 and 2 Crude Oils Tables 1 & 2 summarize the effect of thermal treatment and sulfuric acid catalyzed thermal treatment on key properties of T and K crude oils respectively. As can be seen from the data no significant changes are observed in the total acid number, distribution of naphthenic acids, toluene equivalence and n-heptane insolubles between the thermally treated and sulfuric acid catalyzed thermally treated samples. These data indicate that the chemistry of the crude oil is not significantly altered as a result of sulfuric acid addition prior to thermal treatment. Viscosity as a function of shear rate plots for the untreated and thermally treated T and K crude oils are shown on FIGS. 1A and 1B. Data are plotted for the neat crude, thermally treated crude and thermally treated crude with prior sulfuric acid addition. A reduction in viscosity as a result of thermal treatment is expected. However, it is observed that sulfuric acid addition prior to thermal treatment results in further reduction in viscosity. Viscosity at 0.204 sec −1 as a function temperature plots for the untreated and thermally treated T and K crude oils are shown on FIGS. 2A and 2B. Data are plotted for the neat crude, thermally treated crude and thermally treated crude with prior sulfuric acid addition. From the slope of each plot the corresponding energy of activation was calculated. A decrease in energy of activation is observed for samples subjected to sulfuric acid addition and thermal treatment relative to thermal treatment without prior acid addition. This suggests that sulfuric acid catalyzed thermal treatment has altered fundamental aggregation properties of the chemical species responsible for high viscosities of respective heavy crude ails. Example-3 Vacuum Resid Corresponding data for Arab Heavy Vacuum Resid are shown on FIGS. 3 and 4. Results indicate that the mineral acid enhanced thermal process for resids produces product oil that is substantially decreased in viscosity compared to thermal treatment in absence of mineral acid. TABLE 1 Thermal Treatment of Crude Oil T Treatment Conditions (360° C./6 hrs/ 10 ppm 360° C./6 hrs/ 280 psi/N 2 ) 10 Property None H 2 SO 4 280 psi/N 2 ppm H 2 SO 4 Total Acid 6.1 6.1 3.9 4.1 Number (titration) Acid distribution (micromoles nap acid/g crude) 250MW 61.47 44.83 40.35 300MW 32.80 24.01 21.71 400MW 8.20 5.78 5.05 450MW 19.07 14.03 12.12 600MW 10.49 8.48 7.32 750MW 8.33 8.07 7.54 n-heptane Insolubles 2.6 2.7 2.7 2.7 % Toluene Equivalence 14 14 31 31 TABLE 2 Thermal Treatment of Crude Oil K Treatment Conditions (360° C/6 hrs/ 360° C./6 hrs/ 280 psi/N 2 ) Property None 280 psi/N 2 10 ppm H 2 SO 4 Total Acid 4.2 3.2 3.8 Number (titration) Acid distribution (micromoles nap acid/g crude) 250MW 16.55 13.99 14.27 300MW 15.75 11.33 13.73 400MW 4.12 2.85 3.56 450MW 25.02 17.72 21.78 600MW 23.06 18.42 21.09 750MW 22.96 18.85 20.94 n-heptane Insolubles % <0.1 <0.1 0.9 Toluene Equivalence 0 0 <5
The invention describes a method for decreasing the viscosity of crude oils and residuum utilizing a combination of thermal and acidic treatment. Further, the invention describes a method for making a water-in-oil emulsion, or a solids-stabilized water-in-oil emulsion with a reduced viscosity. The emulsion can be used in enhanced oil recovery methods, including using the emulsion as a drive fluid to displace hydrocarbons in a subterranean formation, and using the emulsion as a barrier fluid for diverting flow of fluids in the formation.
4
BACKGROUND OF THE INVENTION This invention relates to flatbed trailers used for the transport of cargo wherein the cargo is secured to the trailer using flexible cords or straps. In one aspect it relates to a winch crank assembly for rapidly rewinding the straps onto the winch when the straps are not in use. In a specific aspect it relates to a portable winch crank assembly wherein a single crank may be used to rewind the straps on a plurality of winches on a single trailer or on different trailers. Commercial cargo is frequently transported using tractor trailer rigs wherein the trailer is an open flatbed trailer. Numerous types of cargo are transported in this way including timber, lumber, metal stock, and machinery, to name but a few. The cargo is often secured to the trailer by long flexible straps which are placed over or around the cargo transverse the bed length and secured to both sides of the trailer. Woven nylon and/or canvas-type straps are widely used due to their strength, flexibility, and weather resistance. The straps are usually wound on the take-up drum of a winch which is located on one side of trailer. For securing the cargo a sufficient length of the strap is withdrawn from the winch, laid over the cargo, and connected to the opposite side of the trailer using a hook which is fixed to the end of the strap. Once the strap is so disposed, the slack in the strap is taken up by turning the winch until the tension in the strap is sufficient to hold the cargo in place. A problem in the above approach is encountered after the cargo has been removed and the securing strap needs to be rewound onto the winch for storage. For larger, cargo there may be a significant length of strap which needs to be rewound with from twenty to thirty feet not being uncommon. Additionally, for longer cargo, such as lumber, a plurality of individual straps and winches are spaced along the length of the trailer with as many as a dozen or more often employed. In this configuration each strap is rewound individually on its respective winch. In the past this has been done by manually turning the drum of the winch by gripping the drum and turning it in angular increments of about one half turn. By this procedure it is virtually impossible to continuously turn the take-up drum for rewinding the strap. This procedure is complicated by the fact that the winches are usually mounted under the bed of the trailer with very little clearance between the drum and the underside of the bed. Most importantly, for long straps and multiple winches this is a very time consuming process which may require anywhere from two to three minutes per strap depending on the user. Therefore, for rewinding the straps on a dozen winches, the total time required may be up to thirty minutes or more. In addition, the repeated gripping and regripping of the drum as it is turned to rewind the strap causes excessive wear of work gloves which over time can be a significant expense to replace. U.S. Pat. No. 4,884,928 discloses a winch having a crank for rotating the winch for tightening and loosening the strap of a winch used to secure cargo on a flatbed trailer. A problem associated with winches having a crank which is integral with the winch is that for trailers having a plurality of winches, each winch must be fitted with a crank. Also, drivers of tractor trailers and the like often change trailers in the course of delivering cargo. Thus the driver may at some time be using a trailer which is fitted with winches having crank means and at other times using a trailer with winches without crank means. The use of the portable crank of the present invention is designed to solve these problems. SUMMARY OF THE INVENTION The present invention provides a novel crank assembly for rapidly turning winches on flatbed trailers for rewinding the securing straps. The portable crank assembly comprises a rotatable handle that is sized to permit rapid and continuous rotation of the winch for rewinding the straps. The use of the present invention reduces the time required to wind the straps by tenfold or more. A single portable crank assembly may be used to rewind the straps on a plurality of winches on single flatbed trailer. Alternatively, a single portable crank may be conveniently carried by the user for use on different trailers. As explained in detail below, the present winch crank assembly is designed for use with winches which have a strap take-up or dispensing drum which is integral with a protruding hub that has a hollow cylindrical core. These types of winches are presently in widespread use in the trucking industry. The crank assembly comprises a handle having at one end a rotatable grip and at the other end a expandable compression member which may be inserted into the hollow core of the hub. Tightening means are provided whereby a compressive force may be selectively applied to the compression member whereby the member is expanded into compressive engagement with the inner walls of the hub. The frictional force induced between the compression member and the hub permit the continuous rotation of the crank and hub as a unit for rapidly rewinding the securing straps. After rewinding the strap, the tightening means may be loosened whereby the compression member resumes its original shape and thereby disengages from the winch hub. The crank assembly may then be withdrawn and used on a different winch. The utility of the present invention can be appreciated when considering that there are presently thousands of flatbed trailers with winches that have a structure compatible for use with the portable crank assembly of the present invention. The savings in man-hours spent rewinding the securing straps is potentially enormous. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side view of a flatbed trailer equipped with a plurality of winches whereon the present crank assembly may be adapted. FIG. 2 is a sectional view of the flatbed trailer taken along line 2--2 of FIG. 1. FIG. 3 is a frontal view of a winch equipped with the crank of the present invention shown substantially along line 3--3 of FIG. 2. FIG. 4 is a sectional view of the present crank assembly taken along line 4--4 of FIG. 2. DESCRIPTION OF THE PREFERRED EMBODIMENTS FIGS. 1 and 2 illustrate a typical flatbed trailer 10 consisting of bed 11 secured to frame 12 and having railings 13. Cargo 14 is secured on bed 11 for transport by a plurality of flexible straps 15 spaced along the length of the bed. Straps 15 extend transverse the bed length and have a loose end which is rolled onto the take-up drum of winches 16, and at the opposite end the straps are fixed to hook 17 which hooks around railing 13 to secure the strap to the truck bed. Straps 15 may be made of woven nylon fibers or canvas-type materials and hook 17 may be attached by stitching as at 18. Although three straps and winches are shown in FIG. 1, this is by way of illustration only and any number of straps and winches may be employed with up to a dozen or more often employed. The elements of trailer 10 are also by way of illustration and variations are possible without departing from the spirit of the invention. As best seen in FIG. 3, winch assembly 16 comprises frame 21 fixed to the underside of bed 11 using bolts 22, or other means such as welding. Alternatively winch 16 may be fixed to a portion of a frame 12. In either case the winch is mounted to one side of the trailer directly underneath bed 11. Drum 23 is rotatably disposed in frame 21 and serves as a dispensing roll for winding strap 15 thereon. Winch 16 further comprises ratchet mechanism 24 which may be manually engaged or disengaged with drum 23 by a lever (not shown). With ratchet 24 engaged, drum 23 may turn in the take-up direction only (i.e. the direction which winds strap 15 onto drum 23). With ratchet 24 disengaged, drum 23 may turn in either direction for winding or dispensing strap 15. Winch 16 further comprises protruding exposed hub 26 which is secured to or integral with drum 23 so that the hub rotates with the drum. Hub 26 has a hollow core 29 and has holes 27 formed therethrough for receiving a lever bar which is used to tension strap 15 with ratchet 24 engaged. Winch 16 is usually mounted under bed 11 for safety purposes as well as for protecting the winch. While the dimensions may vary from trailer to trailer the clearance distance (labeled "A" in FIG. 3) between the underside of the bed and the longitudinal axis of the drum is typically between 3 to 8 inches. With strap 15 completely rolled onto drum 23 of the winch, the radius of the roll measured from the drum longitudinal axis is greater than about one half the clearance distance "A" depending on the total length of the strap. Thus with strap 15 completely rolled onto drun 23 the clearance between the top of the roiled strap and the bottom of bed 11 is generally less than 1 to 2 inches. The dimension "A" should be as small as possible for safety purposes and to protect the winch from damage, but "A" must be large enough to permit strap 15 to be completely rolled onto drum 23 without the strap contacting the underside of bed 11. Referring to FIGS. 3 and 4, winch assembly 16 is provided with crank assembly 30 which is secured to hub 26 at one end as described below. Crank assembly 30 comprises bar member 31 extending substantially perpendicular to the longitudinal axis of drum 23. Bar 31 has inner end 53 and outer end 54 having secured thereto rotatable wheel-type grip element 32 secured to the bar by bolt 33. Bar 31 may be cut from flat metal bar stock and grip 32 may be cut from round bar stock of hard plastic or metal material. The use of plastics is preferred to reduce corrosion which would hinder the rotation of the grip on bolt 33. As illustrated in FIG. 3, bolt 33 passes through grip 32 and through bar 31. Nut 34 is threaded onto the bolt before inserting the bolt through the bar. Nuts 34 and 35 are counter-tightened onto opposite sides of bar 31 securing the bar thereto. The length of bolt 33 is sized to leave grip 32 rotatably disposed on the bolt in the space between nut 34 and the head of the bolt after nuts 34 and 35 have been tightened. The use of bolt 33 is preferred over pins or rivets because grip 32 may be easily removed and replaced if damaged. As best seen in FIG. 4, crank assembly 30 further comprises cylindrical flexible compression member 37 which is fixed to bar 31 by bolt or pin 38. Member 37 is preferably constructed from a resilient, semi-hard, rubber-like material which is deformable under stress and will return to its original shape when the stress is removed. Pin 38 extends outwardly through hole 39 in member 37 and passes through hole 41 of bar 31. Backup washer 42 acts as a compression plate and is disposed on the inside of compression member radial surface 55, and smaller washer 43 is disposed on the opposite side. Wing nut 44 is threaded onto bolt 38 for securing the compression member to bar 31. Lock washer 52 is provided between bar 31 and nut 44. In the undeformed, or radially relaxed, position the outer diameter of member 37 is sized to permit the member to be slidingly inserted into hollow core 29 of hub 26 thereby presenting exposed surface 47. After inserting the compression member wing nut 44 is tightened by hand which acts to draw washer 42 towards bar inner end 53 thereby creating a compressive stress in member 37. The compressive force causes the outer surface 48 of flexible member 37 to swell outward into a radially compressed position that forces the member against the inner walls of hub 26 as at wall 46. The compressive force creates sufficient friction between member 31 and wall 46 for hub 26 and assembly 30 to become locked together and thereby rotated as a unit without slippage by rotating bar 31 via grip 32. In addition to the compressive force between member 37 and wall 46, the expansion of member 37 causes the member to swell around small washer 43 and exposed surface 47 of the member thereby contacts the inner end of bar 31. Washer 43 is sized to permit a large contact area between member 37 and bar 31 whereby a significant friction force is established therebetween. The friction force eliminates any slippage between bar 31 and member 37 as the crank is turned for rewinding straps 15 onto drum 23. Member 37 generally does not contact bar 31 in the unstressed position. FIG. 4 illustrates member 37 as protruding slightly from hub 26 as at 49. It is equally effective for the member to be inserted entirely into the hub whereby the end of the hub will contact bar 31 as at 51. For removing crank assembly 30 for use on other winches, wing nut 44 is loosened by hand and washer 42 moves away from bar 31 thereby relieving the stress on member 37. Resilient compression member 37 returns to its original shape and size whereby it may be slidably withdrawn from hub 26. The overall length of crank 30 is not critical, however, it is preferably 1 to 2 inches shorter than dimension "A" to permit a continuous 360 degree rotation of the crank. The overall length of bar 31 is preferably between 2 to 6 inches so that the crank assembly may be conveniently carried by the user from winch to winch or from trailer to trailer. In this way it is not necessary for each winch and/or trailer to be fitted with a crank mechanism for deriving the rapid-wind advantage provided by the crank. The use of the present crank 30 reduces the time required to wind strap 15 onto drum 23 by tenfold over winches with no crank. In the latter case the most widely practiced method is to simply grip hub 26 and turn the hub by hand in small angular increments. Other means for selectively moving washer 42 to and away from bar 31 for applying and relieving the compressive stress in member 37, respectively, are possible without departing from the spirit of the present invention.
An improved winch crank assembly for use on typical flatbed trailers whereon cargo is secured using flexible straps is described. The present invention permits the rapid winding of the straps onto the winch and reduces the time required for winding the straps by tenfold or more. The present winch crank assembly comprises a portable crank assembly wherein a single crank can be used to wind the straps onto a plurality of winches on a single trailer. In addition, the portability allows the user to conveniently carry the crank for use on other truck trailers.
1
TECHNICAL FIELD [0001] The present invention relates to a seal ring and more particularly to a seal ring for use in hydraulic equipment such as automatic transmissions of automobiles. BACKGROUND ART [0002] In recent years, there is a demand for reducing the drive loss of automatic transmissions of automobiles in order to improve the fuel consumption of the automobiles. For the purpose of hydraulic sealing, a seal ring is attached to an automatic transmission. However, the friction loss of the seal ring leads to the drive loss of the automatic transmission. To reduce friction of the seal ring is therefore an important task. In addition, the capacity of an oil pump of the automatic transmission is a significant factor that causes the drive loss. There is therefore a demand for reducing the amount of oil leakage from the seal ring thereby reducing the capacity of the oil pump. To reduce the drive loss of the automatic transmission and improve the fuel consumption of the automobile, it is necessary that the seal ring should have low-friction characteristics and low-leakage characteristics. [0003] FIG. 1 shows the basic structure of a hydraulic circuit using a seal ring. The seal ring 1 is attached to a shaft groove (ring groove) 4 formed on the outer peripheral surface of a shaft 2 on each of axially opposite sides of a hydraulic passage 3 . Hydraulic oil supplied from the hydraulic passage 3 is received by a pressure-receiving side-surface 11 and an inner peripheral surface 12 of the seal ring. An outer peripheral surface 13 of the seal ring is in contact with the inner surface of a housing 5 , and a contact side-surface 14 of the seal ring is in contact with a side surface of the shaft groove 4 . The hydraulic pressure is thereby sealed. Generally, the shaft 2 is rotatable, and the housing 5 is stationary, or vice versa. [0004] A method generally used to reduce the friction (friction loss) of a seal ring is to reduce a pressurizing load that presses the contact side-surface of the seal ring serving as a principal sliding surface against the ring groove. More specifically, a seal ring having a cross-sectional shape that allows the pressure of supplied oil to act between the contact side-surface of the seal ring and the ring groove is used to reduce the pressurizing load by the action of a cancelling load. [0005] Patent Literature 1 discloses a method of reducing a pressurizing load by using a seal ring including side surfaces formed in a tapered shape in which an axial width decreases from an outer peripheral side toward an inner peripheral side whereby a cancelling load is generated between a ring groove and a side surface of the seal ring. The tapered shape formed by the side surfaces can significantly reduce the pressurizing load and is currently known as the shape of a seal ring that can minimize friction. [0006] Patent Literature 2 discloses a seal ring that includes circumferentially spaced recessed sections (pockets) 6 formed at least on the inner peripheral side of the contact side-surface, and pillar sections 7 disposed between the recessed sections 6 , as shown in FIG. 2A . As shown in FIGS. 2B and 2C , each of the recessed sections 6 includes a deepest inclined portion 51 formed such that the axial width (thickness) of the seal ring decreases in an inner circumferential direction, and converging portions 52 located on opposite circumferential sides of the deepest inclined portion 51 and converging toward the innermost peripheral points of adjacent pillar sections 7 . In this configuration, when the seal ring rotates, the oil that fills the recessed sections 6 is squeezed along the inclined surfaces of the converging portions 52 to cause lift 60 . In addition, hydraulic pressure acts on the recessed sections 6 on the contact side-surface to bring about a pressing load reduction effect (cancelling pressure 61 ). The friction is thus reduced. In the seal ring in Patent Literature 2, a side surface of the seal ring is in surface contact with the ring groove and slides thereon, as shown in FIG. 2D . Thus, no leakage passage is formed in a gap of the abutment joint of the seal ring, and low-leakage characteristics are thereby obtained. [0007] In the seal ring in Patent Literature 1, the sliding contact between a side surface of the seal ring and the ring groove is line contact, and the circular sliding line is located on the gap of the abutment joint of the seal ring. As a result, the oil leaks from the gap of the abutment joint. Although the use of the recessed sections in Patent Literature 2 reduces the friction, the degree of reduction is lower than that in the seal ring in Patent Literature 1. There is therefore a demand for further reducing the friction. CITATION LIST Patent Literature [0000] Patent Literature 1: Japanese Patent No. 3437312 Patent Literature 2: WO2004/090390 SUMMARY OF INVENTION Technical Problem [0010] The present invention is made in view of the foregoing circumstances, and an object of the present invention is to provide a seal ring that has low-friction characteristics and low-leakage characteristics, can reduce the drive loss of the automatic transmission of an automobile, and can contribute to improvement in fuel consumption of the automobile. Solution to Problem [0011] In view of the above object, the present inventors have made extensive studies and found that, in a seal ring including circumferentially spaced recessed sections formed on the inner peripheral side of a contact side-surface and pillar sections disposed between the recessed sections, the circumferential opposite ends of each of the recessed sections are formed as squeezing portions formed of curved surfaces convex toward the pillar sections, whereby lift generated by squeezing oil was increased and friction was reduced. The invention was thus completed. More specifically, the seal ring of the present invention is attached to a shaft groove formed on the outer peripheral surface of a shaft and includes a plurality of recessed sections on the inner peripheral side of the contact-side surface of the seal ring. The recessed sections are circumferentially spaced apart from each other with pillar sections interposed therebetween. The circumferential opposite ends of each of the recessed sections are formed as squeezing portions formed of curved surfaces convex toward the pillar sections. Advantageous Effects of Invention [0012] In the present invention, the recessed sections circumferentially spaced apart from each other with pillar sections interposed therebetween are provided on the inner peripheral side of the contact-side surface. The circumferential opposite ends of each of the recessed sections are formed as squeezing portions formed of curved surfaces convex toward the pillar sections. The pillar sections and the recessed sections are connected with each other through a gentle R shape, thereby improving the oil squeezing effect and increasing the lift. The friction can thus be effectively reduced. The seal ring of the present invention can also prevent oil leakage because the contact-side surface and the ring groove side surface are in surface contact. The seal ring of the present invention has both low friction characteristics and low leakage characteristics and therefore can effectively reduce the drive loss of the automatic transmission. BRIEF DESCRIPTION OF DRAWINGS [0013] FIG. 1 is a cross-sectional view illustrating a hydraulic circuit having a seal ring attached thereto. [0014] FIG. 2A is a plan view illustrating the structure of a seal ring described in Patent Literature 2, FIG. 2B is a perspective view thereof, FIG. 2C is a linear development view in a circumferential direction illustrating the shape of recessed sections as viewed from an inner peripheral surface, and FIG. 2D is a schematic diagram illustrating the seal ring described in Patent Literature 2, with the seal ring being attached to a ring groove. [0015] FIG. 3A is a perspective view illustrating an embodiment of the seal ring of the present invention, and FIG. 3B is a linear development view illustrating the shape of a recessed section of the seal ring shown in FIG. 3A as viewed from an inner peripheral surface. [0016] FIGS. 4A and 4B are perspective views illustrating other embodiments of the seal ring of the present invention, and FIG. 4C is a scan image of a contact side-surface of the seal ring in FIG. 4A . [0017] FIG. 5 is a perspective view showing an embodiment of an abutment joint of the seal ring of the present invention. [0018] FIG. 6 is a schematic diagram illustrating a friction measurement apparatus. [0019] FIG. 7 is a graph showing the relations between the depth of a deepest portion and friction of the seal rings in Examples 1 to 5 () and Examples 6 to 10 (▪). [0020] FIG. 8 is a graph showing the relations between the length of an inner wall and friction. DESCRIPTION OF EMBODIMENTS [0021] A seal ring of the present invention will be described in details below with reference to the figures. [0022] FIG. 3A shows a perspective view illustrating the seal ring of the present invention, and FIG. 3B shows a linear development view in a circumferential direction illustrating the seal ring in FIG. 3A as viewed from an inner peripheral surface. In the following description, the linear portion in the linear development view above is called a planar surface or a flat surface, and the curved portion is called a curved surface. In the present embodiment, as shown in FIG. 3B , the opposite ends of a recessed section 6 are formed as curved surfaces convex toward pillar sections 7 , that is, squeezing portions 20 which are formed of curved surfaces convex upward in the linear development view ( FIG. 3B ) in the circumferential direction as viewed from the inner peripheral surface and the squeezing portions 20 are connected with the pillar sections 7 . In this way, the pillar section 7 and the recessed section 6 are connected through a gently sloped curved surface, so that the squeezing effect is improved when compared with the shape of the recessed section 6 of the seal ring in Patent Literature 2. This increases the lift and reduces the friction. In the present embodiment, as shown in FIG. 3B , the recessed section 6 has a deepest portion 21 formed at the center of the recessed section 6 in parallel with the side surface, and curved surfaces convex toward the deepest portion 21 , that is, inclined surface portions 22 formed as curved surfaces convex downward in FIG. 3B to extend from the opposite ends of the deepest portion 21 toward the squeezing portions 20 . The inclined surface portions 22 and the squeezing portions 20 are also connected at their boundaries through gently curved surfaces. The inclined surface portions 22 having such a configuration can achieve a higher friction reduction effect. The inclined surface portions 22 in the seal ring of the present invention are not limited to the structure formed of these curved surfaces and may be formed of single flat surfaces or of flat surfaces and curved surfaces. [0023] Here, the depth “h” of the deepest portion 21 , that is, the axial width of the deepest portion 21 is preferably 2 to 17 and more preferably 5 to 10 when the axial width of the seal ring is 100. The depth “h” of the deepest portion 21 set in this range can achieve a higher friction reduction effect. [0024] In FIG. 3 , the deepest portion 21 is formed as a flat surface having a prescribed circumferential length and parallel to the side surface. The deepest portion 21 , however, may not be a flat surface. More specifically, the recessed section 6 may be configured such that the center of the recessed section 6 is formed of an inclined surface portion 22 including the deepest portion 21 and having a shape convex toward the deepest portion 21 , in other words, a single curved surface having a shape convex toward the deepest portion 21 , that is, as a single curved surface convex downward in FIG. 3B , and that the opposite ends of the inclined surface portion 22 and the pillar sections 7 are connected through squeezing portions 20 convex toward the pillar sections 7 , that is, formed of curved surfaces convex upward in FIG. 3B . To obtain a higher friction reduction effect, it is preferable to form the deepest portion 21 as a flat surface parallel to the side surface. In this case, the circumferential width “b” of the deepest portion is 2 to 20 and more preferably 8 to 16 when the circumferential width “a” of one recessed section 6 is 100. [0025] A droop length “c” of an R curved surface of the squeezing portion 20 , that is, the circumferential length from the top end of the recessed section 6 to the boundary between the squeezing portion 20 and the inclined surface portion 22 , is preferably 5 to 20 when the circumferential width of the inclined portion on one side of the recessed section 6 , that is, the sum (c+d) of the circumferential widths of squeezing portion 20 and the inclined surface portion 22 , is 100. The depth “e” of the squeezing portion 20 , that is, the amount of reduction in the axial direction at the boundary point between the squeezing portion 20 and the inclined surface portion 22 , is more than zero and equal to or smaller than 20% where the depth “h” (the amount of reduction in the axial direction) of the deepest portion of the recessed section 6 is 100. [0026] Although depending on the size of the seal ring, the number of recessed sections 6 (the number of recessed sections formed on one side surface of one seal ring) is preferably 4 to 16 and more preferably 6 to 10 when the seal ring has an outer diameter (nominal diameter) of about 20 to 70 mm. The circumferential width of the recessed section 6 is a factor that has a great effect on the friction reduction effect. A more significant friction reduction effect can appear when the recessed sections 6 with a large circumferential width are formed than when a large number of recessed sections 6 with a small circumferential width are formed. The circumferential width “a” of one recessed section 6 is preferably 3 to 25 and more preferably 5 to 15 when the outer peripheral length of the seal ring is 100. The circumferential width “a” of one recessed section 6 is preferably 5 to 20 times the circumferential width “f” of one pillar section 7 . [0027] The advantageous effects of the present invention are achieved by forming the recessed sections 6 on the contact side-surface of the seal ring. The shape of each of the recessed sections 6 in this embodiment is symmetric on opposite sides with respect to the center in the circumferential direction. In consideration of workability, it is therefore preferable to provide the recessed sections 6 on both the contact side-surface and the pressure-receiving side-surface of the seal ring such that each of these side surfaces is symmetric and not directional. [0028] FIGS. 4A and 4B show other embodiments of the seal ring of the present invention having an inner wall 8 on the inner peripheral end of the recessed section 6 . In the embodiment shown in FIG. 4A , the inner walls 8 extend from the circumferential opposite ends of the recessed section 6 toward the center of the recessed section 6 along the inner peripheral end portion, and an oil introduction opening 10 that opens toward the inner peripheral surface 12 is provided at the center of the recessed section 6 . The provision of the inner walls 8 on the inner peripheral side (end portion) of the recessed section 6 prevents the flow of squeezed oil from the wedge-like inclined surface (squeezing portion) to the inner peripheral surface 12 . The depth of the wedge-like cross section and the three-dimensional squeezing effect in the circumferential direction generate even larger lift. An oil film is therefore formed at the pillar section to cause the pillar section to float up and facilitate introduction of oil onto the annular seal surface located on the outer peripheral side of the recessed section 6 . The coefficient of friction is thus reduced. In addition, hydraulic pressure acts on the recessed sections 6 on the contact side-surface thereby reducing the pressing load. As a result of the synergetic effect of these, the friction is further reduced. In the seal ring of this embodiment, the pillar section 7 and the recessed section 6 are connected with a gently inclined R shape formed therebetween. The provision of the inner walls 8 therefore further improves the squeezing effect and increases the lift, thereby further reducing the friction. In this embodiment, the inner walls 8 are formed on the opposite sides of each of the recessed sections 6 , that is, on the opposite sides of each oil introduction opening 10 . In this case, the circumferential length of one inner wall 8 is preferably 20 to 45 when the circumferential length of one recessed section 6 is 100. The total length of the inner walls 8 on both sides is preferably 40 to 90 when the total circumferential length of one recessed section 6 is 100. In this range, a higher wedge shape effect is obtained, and the friction is further reduced. [0029] The advantageous effects of the present invention are achieved by forming the recessed sections 6 on the contact side-surface of the seal ring. The shape of each of the recessed sections 6 in this embodiment is symmetric on opposite sides with respect to the center in the circumferential direction. In consideration of workability, it is therefore preferable to provide the recessed sections 6 on both the contact side-surface and the pressure-receiving side-surface of the seal ring such that each of these side surfaces is symmetric and not directional. [0030] In FIG. 4A , the inner walls 8 are provided on opposite ends of the recessed section 6 . However, as shown in FIG. 4B , an inner wall 8 may be provided exclusively at the end portion of the inclined surface (squeezing portion 20 ) on the rear side in the rotation direction. In this configuration, the clockwise rotation of the seal ring causes the oil to be squeezed toward the edge of the squeezing portion 20 on the rear (left) side in the rotation direction, whereby lift is generated (the wedge shape effect). The wedge shape effect occurs in the squeezing portion 20 on the rear side in the rotation direction as described above, whereas an oil film is less likely to be formed and the lubrication state tends to be inhibited on the inclined surface on the front side in the rotation direction. In this embodiment in which the inner walls 8 are provided exclusively on the rear side in the rotation direction, therefore, the friction is further reduced. [0031] When the inner walls are provided exclusively on the rear side in the rotation direction, the circumferential length of each inner wall 8 is preferably 5 to 95 and more preferably 50 to 95 when the total circumferential length of the recessed section is 100. In this range, a higher wedge shape effect is obtained, and the friction is further reduced. [0032] FIG. 4C shows a scan image of the contact side-surface of the seal ring in FIG. 4A . Each inner wall 8 is inclined at an inclination angle of 4° such that its radial width increases from a position about 4 mm from one end of the recessed section 6 toward the one end of the recessed section, that is, such that the radial width of the recessed section decreases. In addition, a sealing surface on the outer peripheral side of the recessed section 6 is inclined at an inclination angle of 3° such that its radial width increases toward the one end of the recessed section 6 , that is, such that the radial width of the recessed section 6 decreases. In this embodiment, the seal ring includes recessed sections 6 each having a tapered shape in which its radial width decreases toward one end and the axial width (the depth) also decreases, so that the three-dimensional squeezing effect is further improved. This increases the lift and further reduces the friction. In this embodiment, the ends of each of the recessed sections 6 are formed as curved surfaces. [0033] In FIGS. 4A and 4B , the axial level of each inner wall 8 is set to be substantially the same as the level of the side surface of the seal ring, that is, such that the end surface of the inner wall 8 is flush with a portion of the side surface on which no recessed sections 6 are formed. By arranging the inner walls 8 discontinuously in the circumferential direction, oil introduction openings 10 that open toward the inner peripheral surface 12 are formed between the inner walls 8 and 8 in FIG. 4A or between the inner walls 8 and the pillar sections 7 in FIG. 4B . The configuration of the oil introduction openings 10 , however, is not limited to the above configurations. For example, an inner wall 8 may be formed over the entire circumference of each of the recessed sections 6 . In this case, an oil introduction opening 10 may be formed by setting the axial level of the inner wall 8 to be lower than the level of the side surface of the seal ring partially. [0034] In consideration of attachability, the seal ring of the present invention has an abutment joint. The shape of the abutment joint is not particularly limited. Examples thereof include a right-angle (straight) abutment joint, an inclined (angle) abutment joint, a stepped abutment joint, a double angle abutment joint, a double cut abutment joint, and a triple step abutment joint shown in FIG. 5 . To block the flow of oil into the gap of the abutment joint and improve the sealability, a double angle abutment joint, a double cut abutment joint, and a triple step abutment joint are preferred. [0035] Examples of the material of the seal ring of the present invention include polyether ether ketone (PEEK), polyphenylene sulfide (PPS), polyimide (PI), and fluorine-based resins such as polytetrafluoroethylene (PTFE), modified polytetrafluoroethylene, and ethylene tetrafluoroethylene (ETFE), although not particularly limited thereto. Generally, a material obtained by adding an additive such as carbon powder or carbon fibers to any of the above resins is used. [0036] A production method for the seal ring of the present invention is not particularly limited. When a thermoplastic resin such as PEEK, PPS, or PI is used as the material of the seal ring, injection molding is preferred. By using a mold for injection molding, a seal ring having a complicated structure can be readily produced. When a fluorocarbon resin is used, a seal ring can be produced by compression molding followed by machining. EXAMPLES [0037] Although the present invention will be described in more details with the following examples, the present invention is not limited to those examples. Example 1 [0038] A seal ring having a recessed section structure shown in FIG. 3A was produced by injection molding using a PEEK material including carbon fibers added thereto. Eight recessed sections each having a deepest portion of 0.22 mm in depth and a circumferential width of 24 mm were formed on each of the contact-side face and the pressure-receiving surface, where the curvature of the squeezing portion was R40. The outer diameter (nominal diameter) of the seal ring was 67 mm, the thickness (radial width) thereof was 2.3 mm, and the width (axial width) thereof was 2.32 mm. The abutment joint was a triple step abutment joint shown in FIG. 5 . The depth of the deepest portion was 9.5 where the axial width of the seal ring was 100. The circumferential width of the deepest portion was 16.9 where the circumferential length of one recessed section was 100. The droop length of the R curved surface of the squeezing portion was 13.9 where the sum of the circumferential widths of the squeezing portion and the inclined portion was 100. The depth of the squeezing portion was 15.0 where the depth of the deepest portion of the recessed section was 100. Comparative Example 1 [0039] A seal ring having a recessed section structure shown in FIG. 2B was produced by injection molding using a PEEK material including carbon fibers added thereto. The inclination angle θ of the recessed section was set to 16°, and the depth “h” of the deepest inclined portions 52 was set to 0.42 mm. Eight recessed sections were formed on each of the contact side-surface and the pressure-receiving side-surface. The outer diameter (nominal diameter) of the seal ring was 67 mm, the thickness (radial width) thereof was 2.3 mm, and the width (axial width) thereof was 2.32 mm. The abutment joint was a triple step abutment joint shown in FIG. 5 . Comparative Example 2 [0040] A seal ring having a trapezoidal cross-section with its opposite side surfaces being inclined at an inclination angle of 5° such that the axial width decreases from the outer peripheral side toward the inner peripheral side was produced by injection molding using a PEEK material including carbon fibers added thereto. The outer diameter (nominal diameter) of the seal ring was 67 mm, the thickness (radial width) thereof was 2.3 mm, and the width (axial width) thereof was 2.32 mm. The abutment joint was a triple step abutment joint shown in FIG. 5 . [0041] Measurement of Friction and Amount of Oil Leakage [0042] The seal rings in Example 1 and Comparative Examples 1 and 2 were each attached to a shaft groove formed on the outer peripheral surface of a stationary shaft (made of S45C) having a hydraulic circuit provided therein, as shown in FIG. 6 , and the stationary shaft was placed in a test apparatus. A housing (made of S45C) was then attached and rotated at 2000 rpm, and the loss of rotation torque was detected using a torque detector attached to the test apparatus. The amount of oil leakage was measured at the same time. The oil used was automatic transmission fluid (ATF). The temperature of the oil was set to 80° C., and the pressure of the oil was set to 0.8 MPa. [0043] The friction was reduced by 10% or more in the seal ring of Example 1 compared with the seal ring in Comparative Example 1. The reason for this may be as follows. In the seal ring in Example 1, the circumferential opposite ends of the recessed section are formed as the squeezing portions formed of curved surfaces convex toward the pillar sections, whereby lift generated by squeezing oil is increased. [0044] The amount of oil leakage in Example 1 was reduced to about two thirds of the amount of oil leakage in Comparative Example 2, as in Comparative Example 1. It was found that the seal ring of the present invention had superior leakage characteristics. Examples 2 to 5 [0045] Seal rings having a recessed section structure shown in FIG. 3A were produced by injection molding using a PEEK material including carbon fibers added thereto, in a similar manner as in Example 1. Here, the curvature of the squeezing portion was changed such that the depth “h” of the deepest portion was 0.03 mm (Example 2), 0.08 mm (Example 3), 0.12 mm (Example 4), and 0.41 mm (Example 5). The outer diameter (nominal diameter) of the seal ring was 67 mm, the thickness (radial width) thereof was 2.3 mm, and the width (axial width) thereof was 2.32 mm. The abutment joint was a triple step abutment joint shown in FIG. 5 . The depth of the deepest portion of Examples was 1.3 (Example 2), 3.4 (Example 3), 5.2 (Example 4), and 17.7 (Example 5) where the axial width of the seal ring was 100. The friction and the amount of oil leakage of the resultant seal rings were measured in a similar manner as in Example 1. [0046] The relations between the depth “h” of the deepest portion and friction of the seal rings in Examples 1 to 5 are plotted as shown in FIG. 7 (). Here, the ordinate represents the friction as a relative value where the friction of the seal ring in Comparative Example 1 is 100. The abscissa represents a relative value of the depth “h” of the deepest portion of each seal ring where the axial width of the seal ring is 100. [0047] It was found that the friction was reduced in Examples of the present invention in which the circumferential opposite ends of each of the recessed sections were formed as squeezing portions formed of curved surfaces convex toward the pillar sections, when compared with the conventional shape of the recessed sections. In particular, the friction was reduced when the depth “h” of the deepest portion was in the range from 2 to 17, and the friction was further reduced in the range of 5 to 10, where the axial width of the seal ring was 100. [0048] In Examples 1 to 5, although it was found that the amount of oil leakage in the seal ring had a tendency to slightly increase inversely with the reduction of friction, the amount of oil leakage was merely two thirds of the amount of oil leakage in Comparative Example 2, as in Comparative Example 1. It was thus confirmed that the seal ring of the present invention also had superior sealability. Examples 6 to 10 [0049] Seal rings having a recessed section structure shown in FIG. 4A were produced by injection molding using a PEEK material including carbon fibers added thereto. Inner walls having a width of 0.3 mm and a circumferential length of 10 mm for each side were provided from the opposite ends of each of the recessed sections toward the center along the inner peripheral end, and an oil introduction opening having a circumferential length of 4 mm was formed at the center. Here, the seal rings were produced with the curvature of the squeezing portion being changed such that the depth “h” of the deepest portion was 0.03 mm (Example 6), 0.08 mm (Example 7), 0.12 mm (Example 8), 0.22 mm (Example 9), and 0.41 mm (Example 10). The outer diameter (nominal diameter) of the seal ring was 67 mm, the thickness (radial width) thereof was 2.3 mm, and the width (axial width) thereof was 2.32 mm. The abutment joint was a triple step abutment joint shown in FIG. 5 . The friction and the amount of oil leakage of each seal ring were measured in a similar manner as in Example 1. [0050] The results of measurement of friction of the seal rings in Examples 6 to 10 are shown in FIG. 7 (▪). Here, the ordinate represents the friction as a relative value where the friction of the seal ring in Comparative Example 1 is 100. The abscissa represents the depth “h” of the deepest portion of each seal ring where the axial width of the seal ring is 100. As can be understood from FIG. 7 , the provision of the inner walls in the seal ring of the present invention can further reduce the friction. The reason for this may be as follows. In the seal ring of the present invention, the end portions of the recessed section are formed as curved surfaces convex toward the pillar sections, and the pillar sections and the recessed sections are connected with each other at a gentle inclination angle. Accordingly, the provision of the inner walls allows the oil to be squeezed to the end of the recessed section more effectively. This increases the lift, facilitates formation of an oil film at the pillar sections, and lubricates the seal surface, thereby reducing the coefficient of friction. Examples 11 to 14 [0051] As shown in FIG. 4B , seal rings having the same configuration as Example 1 were produced except that an inner wall having a circumferential length of 14.4 mm (Example 11), 10 mm (Example 12), 6.6 mm (Example 13), and 3.3 mm (Example 14) was provided exclusively on the rear side in the rotational direction. Here, as the circumferential length of the recessed section was 24 mm, the respective circumferential lengths of the inner walls of Examples 11, 12, 13, and 14 were equivalent to 60%, 42%, 28%, and 14% of the circumferential length of the recessed section, respectively. The friction and the amount of oil leakage of each seal ring were measured in a similar manner as in Example 1. [0052] The relations between the length of the inner wall and friction of the seal rings in Examples 11 to 14 are plotted in FIG. 8 . Here, the length of each inner wall is represented as a relative value where the circumferential length of the recessed section is 100. The friction in each Example is represented as a relative value where the friction in Example 1 without inner walls is 100. The value in Example 9 having inner walls on the opposite sides of the recessed section is also shown in FIG. 8 (▪). In all of Example 9 having inner walls on the opposite sides and Examples 11 to 14 having inner walls exclusively one side (the rear side in the rotational direction), the friction reduction effect was observed when compared with Example 1 without inner walls. Here, it was found that the friction was further reduced in Examples 11 to 14 having inner walls exclusively on the rear side in the rotational direction, when compared with Example 9 having inner walls on opposite sides of the recessed section. [0053] The reason for this may be assumed as follows. On the rear side in the rotation direction, the lift caused by the wedge shape is large. On the front side in the rotation direction, the lift generated by the wedge shape is small, an oil film is less likely to be formed on each inclined surface, and the lubrication state tends to be inhibited. Thus, when inner walls are provided exclusively on the rear side in the rotation direction and no inner walls are provided on the front side in the rotation direction, the sealing surface is lubricated. It was also found that, when the inner walls were provided exclusively on the rear side in the rotation direction, a higher friction reduction effect was obtained by setting the circumferential length of the inner wall to 5 to 95 and preferably 50 to 95 where the circumferential length of the recessed section was 100. [0054] Generally, the larger the cancelling area, that is, the area subjected to the oil pressure is, the larger the force that presses back as counterforce is. As a result, the pressurizing load is reduced, and the friction is thus reduced. In the seal ring of the present invention, however, a higher friction reduction effect can be achieved by increasing the length of the inner wall, that is, by reducing the cancelling area. This is presumably because the inner walls installed thereon prevent the flow of oil onto the inner peripheral surface and efficiently introduce the oil to the inclined surfaces of the squeezing portions. Thus, when the seal ring rotates, larger lift is generated to facilitate formation of an oil film on the pillar sections. The formation of the oil film on the pillar sections causes the inner peripheral side of the seal ring to float up and facilitates introduction of the oil onto the annular sealing surface located on the outer peripheral side of the recessed sections. This causes the sliding surface to be fluid-lubricated. The coefficient of friction is thus reduced, and a high friction reduction effect is obtained. In other words, the friction reduction effect in the seal ring of the present invention is largely dependent on the reduction of the coefficient of friction due to the lubrication of the sliding surface, rather than the reduction of the pressing load. In the seal ring of the present invention in which friction can be reduced with a smaller cancelling area as described above, critical characteristics can be improved and the amount of abrasion can be reduced when compared with the conventional seal ring that is largely dependent on the cancelling area. REFERENCE SIGNS LIST [0000] 1 seal ring 2 shaft 3 hydraulic passage 4 shaft groove 5 housing 6 recessed section (pocket) 7 pillar section 8 inner wall 10 oil introduction opening 11 pressure-receiving side-surface 12 inner peripheral surface 14 contact side-surface 20 squeezing portion 21 deepest portion 22 inclined surface portion 51 deepest inclined portion 52 converging portion 60 lift 61 cancelling pressure
Provided is a seal ring which has low-friction characteristics and low-leakage characteristics, reduces drive loss of the automatic transmission of an automobile, and contributes to improvement in fuel consumption of the automobile. The seal ring is attached to a shaft groove on the outer peripheral surface of a shaft. A plurality of recessed sections circumferentially spaced apart from each other with pillar sections interposed therebetween are formed at least on the inner peripheral side of a side surface of the seal ring in contact with the shaft groove. The circumferential opposite ends of each of the recessed sections are formed as squeezing portions formed of curved surfaces convex toward the pillar sections. The depth “h” of a deepest portion in which the axial width of the recessed section is the largest is set in the range of 2 to 17 where the axial width of the seal ring is 100.
5
CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application claims priority from U.S. Provisional Patent Application, Ser. No. 61/234,449, filed 17 Aug. 2009, incorporated by reference herein. STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT [0002] Not applicable REFERENCE TO A “MICROFICHE APPENDIX” [0003] Not applicable BACKGROUND OF THE INVENTION [0004] 1. Field of the Invention [0005] The present invention relates to fabric bulk bags. More particularly, the present invention relates to a novel bulk bag configuration wherein the bottom of the bag has an octagonal or other multi-sided shape which, when filled with product, is fully supported by the pallet without the bag needing to shift and lean. As a result, the side walls stay naturally in position. This bag is more attractive and much safer to stack upon. [0006] 2. General Background of the Invention [0007] In the art of making bulk bags, the historical designs have all been created from the point of view of manufacturing efficiency. The goals have been to eliminate waste and reduce manpower. [0008] Hence, almost all bulk bags have been made with square or rectangular bottoms with vertical walls rising up from the four sides. A good example of this would be the original designs of Peter Nattrass, one of the early inventors of the bulk bag concept. [0009] This concept eliminates any lost fabric and makes production quite efficient with straight sewing lines in all major seams. [0010] However, in usage, a bulk bag is simply a box shaped flexible fabric container. As loose product is poured into the bag, it applies equal pressure in all directions. Uncontained loose product when poured onto the ground forms a cone with a circular shaped bottom. When this natural action is applied to product entering into a fabric bag, the natural forces attempt to change the bag into a cylinder. [0011] In the lower portions of the bag, this cannot occur as the fabric that is directly attached to the square bottom is held to that configuration. But the further up the vertical walls of the bag from the bottom, the less control the bottom square has over the side wall fabric. Within the first 10 inches (25 cm) of the vertical sidewalls above the bottom square panel, the shape of the bag becomes cylindrical. The constraints of the square bottom no longer applies. The flexible bag forms a nearly perfect cylinder in the central portions of the filled bulk bag. [0012] The perimeter of the bag becomes the circumference of the cylinder. Bulk bags come in a variety of sizes. The most common are 34 inches (86 cm) square, 35 inches (89 cm) square, 36 inches (91 cm) square, 37 inches (94 cm) square and 38 inches (97 cm) square. [0013] For purposes of discussion we will use the 37 inch (94 cm) square bag for all the following discussions but it is clear that this new design can be applied to all sizes of bags by using the same thought processes described below. [0014] A bulk bag that is made 37 inches by 37 inches (94 cm by 94 cm) square has a perimeter of 37 inches (94 cm) times 4, or 148 inches (376 cm). A cylinder with a 148 inch (376 cm) perimeter has a diameter of 148/Pii (3.1416) or 47.1 inches (120 cm) in diameter. [0015] Therefore a filled bulk bag that started out as a 37 inch (94 cm) square bag has a square bottom of 37×37 inches (94 cm×94 cm) and an area of 1369 square inches (8832 square cm). Approximately 7 to 8 inches (18 to 20 cm) above the floor the bag has rounded out to a cylinder with a diameter of 47.1 inches (120 cm) and a cross sectional area of 1742 square inches (11,238 square cm). [0016] The resulting cylinder has an area that is greater than the base by 27.2%. This then leads to the conclusion that approximately 25% of the product within each standard bulk bag design is initially unsupported by the pallet or floor. This means that each side of the square bottom bag has unsupported columns of product that are greater than 6% of the total product. [0017] Since the bag has no supporting structure, the loose product outside the support area of the floor or pallet will shift downward during the vibration of handling. [0018] This movement will continue until the great majority of the product within the bag has reached a supported position. [0019] Since the diameter in this case is 10 inches (25 cm) larger than the cross section of the base, the only way for the product to reach support is to convert a portion of the bag sidewall into a floor. In other words, 5 inches (13 cm) of sidewall will be laid flat to gain the support for the product in the 25% of unsupported cylinder that was described above. [0020] If this happens evenly all around the bag, then the bag simply becomes approximately 5 inches (13 cm) shorter with a cylindrical shape from the floor or pallet to the top of the product area. [0021] However, with any inertia such as happens with transport, the product settles to the floor more quickly in one direction versus the other directions. In this case, the product will lay more than 5 inches (13 cm) horizontally to that one side to reach support. This natural action then results in causing the bag to lean in that same direction. One side is longer than the opposite side so the bag is forced to lean toward the newly shortened side. [0022] This is the basic cause of the instability that most bulk bags exhibit when being shipped or being stacked. [0023] The only known exceptions to this are bulk bag designs called baffle bags and some bulk bags that are made with a fully circular bottom. In the case of baffled design bags, the main body of the bag has interior walls that prevent the bag from reshaping itself into a cylinder. While this is an option, it is a fairly expensive option that requires extra fabrics and extra sewing seams. Further, it separates the interior of the bag into 5 separate chambers. The baffle bag essentially tries to overcome the natural forces of gravity by force. [0024] The proposed invention in this patent is attempting to work with the natural forces by providing a more natural rounding to the bag base. [0025] The other known prior art are bags that have a circular bottom, for example, from Japan. While this bag is very stable, it is difficult to place on a square pallet. It has no straight sides to help the operator line up the edges. Further, the 47 inch (119 cm) diameter bag would have to be on a minimum 47 inch (119 cm) square pallet for full support. Since export containers are only 92 inches (234 cm) wide, 2 pallets of this side cannot fit into the containers side by side. Therefore, the bag will have areas of non-support that droop down over the edge of the necessarily smaller pallet and be vulnerable to damage. The invention proposed here eliminates this particular issue with the fully circular bottom bag. [0026] However, after 30 years of International recognition, this design has not moved successfully into the rest of the world. This has been primarily because of the expense and difficulty of producing this design. [0027] In producing the same bag spoken about above, the perfect circle of 47.1 inch (120 cm) would have to be created from a minimum of a 51 inch (130 cm) square piece of fabric. The bottom panel on a bulk bag is a supporting panel and thus generally involves at least one fold of fabric to create two layers at all points of the seam. This means that the bottom requires a piece of fabric with an area of 2,601 square inches (16,781 square cm). [0028] The bottom for the same bag in standard square design is made from 42×42 inches (107×107 cm) fabric with an area of 1764 square inches (11,381 square cm) of fabric. Therefore, the circular bottom requires 47% more fabric than the bottom of the square bag. [0029] In a production situation, the sewing machines used in this industry are designed for straight line sewing. It is quite difficult for this type of machine to apply a seam in a circular manner. The operator must sew only an inch or two (3 to 5 cm) then stop and turn the fabric slightly. This happens approximately 74 times on this type of bag. This number of stops makes the cost of labor go up and the speed of production goes down. [0030] Therefore, there is a need in the industry to provide a bag which will be stable when filled, yet which will be easy to construct without creating wasted fabric or slows down production, as does round bags. The present invention, which is a bag having an octagonal bottom, solves those problems. By going to an octagonal bottom, we speed up the sewing, reduce the waste, fit pallets and provide an appearance that is not square but also not round, which provides a larger footprint when the bag is filled to avoid the side walls of the bag from making contact with the surface upon which the bag rests and causing the filled bag to sag and being unable to support filled bags stacked on top of it. BRIEF SUMMARY OF THE INVENTION [0031] The present invention solves the problems in the art in a simple and straightforward manner. What is provided is a fabric bulk bag and a method of constructing same, the bag including a continuous sidewall, which may or may not be constructed of panels of fabric sewn edge to edge to define the continuous sidewall, a top portion, and a bottom, all defining a bulk storage place therein; the bottom further comprising multiple sides, preferably eight sides, which define an octagonal shape, so that the bag wall is sewn to the bottom in less time than a round shape bag, and when filled the bag stands more upright to support other filled bags thereupon. In the method of producing the fabric bulk bag, the bag is constructed in less time than prior art round bags, uses less wall fabric than prior art square bags, and when constructed and filled, supports itself more stable on a floor or pallet; using the following steps of providing a continuous length of fabric sewn along a common edge to define a continuous wall portion of the bag; sewing a top to the upper edge of the continuous side wall portion of the bag; providing an octagonal shaped bottom of the bag; and sewing a straight seam between the lower edge of the side wall along each of the eight sides of the octagonal shaped bottom which results in quicker time to construct the bag and reduces or eliminates the bulging of the side walls when the bag is filled with bulk product. [0032] Therefore, it is a principal object of the present invention to provide a new design for a bulk bag having multiple sides, greater than four in number, and would have a shape other than the current square or round shape of conventional bulk bags, which results in a bag having a larger footprint for supporting itself upright when filled with product. [0033] It is a further principal object of the present invention to provide a new design for a bulk bag having an octagonal shape which results in a bag using less fabric than round bags for the bottom, less side wall fabric than square bags, and is faster to construct than a current round bottom bag. [0034] It is a further object of the present invention to provide a bulk bag having an octagonal shaped bottom which is not necessarily unilateral in shape, and can be adjusted to match any particular pallet size that the consumer wishes to match. [0035] It is a further object of the present invention to provide a bulk bag having an octagonal shaped bottom which rests securely on a pallet without leaning and maintains substantially straight sides when the bag is filled with bulk material. [0036] It is a further object of this invention to provide a new base design that will improve stability for the filled bulk bags that is also economical to produce. [0037] Further, in summary, the present invention provides a design for a bulk bag that eliminates the natural tendency for filled bags to lean while providing an efficient manner of production. This is accomplished by creating an octagonal shape for the bottom of the bag. [0038] In the preferred embodiment, the shape of at least the bag bottom is eight-sided, or octagonal shape. The top of the bag may also be octagonal but is not necessary for the invention. However, the term multi-sided bag may be used to describe that embodiment and any other embodiment which may include sides which number greater than four. [0039] For purposes of discussion, the continuous sidewall portion of the octagonal bag may be constructed of a one piece of fabric, or it may have a plurality of fabric panels sewn together at their edges to define the continuous sidewall as used herein. BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS [0040] For a further understanding of the nature, objects, and advantages of the present invention, reference should be had to the following detailed description, read in conjunction with the following drawings, wherein like reference numerals denote like elements and wherein: [0041] FIGS. 1A through 4C illustrate the current state of the prior art in square bottom and round bottom bulk bags; [0042] FIGS. 5A through 5C illustrate the steps involved in forming the octagonal bottom of the bag from a square sheet of fabric in a preferred embodiment of the octagonal bottom bag of the present invention; [0043] FIG. 6 illustrates a bottom view of the octagonal bottom bag, after it has been cut to the various dimensions of each of the eight sides of the bottom of a preferred embodiment of the present invention; [0044] FIG. 7 illustrates an additional embodiment of the multi-sided bulk bag illustrating the bag cut having a hexagonal configuration; [0045] FIG. 8 illustrates an overall view of an octagonal bottom bag filled with product set upon a conventional pallet; [0046] FIG. 9 illustrates two octagonal bottom bags filled with product set upon a pallet; [0047] FIG. 10 illustrates an underside view of a filled octagonal bottom bag filled with product set upon a conventional pallet; and [0048] FIG. 11 illustrates an overall view of one octagonal bottom bag filled with product being supported atop a second octagonal bottom bag filled with product. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT [0049] Prior to turning to the bulk bag of the present invention, reference is made to FIGS. 1A through 4C to discuss the prior state of the art in bulk bags in general. [0050] In FIG. 1A there is illustrated a bulk bag 10 of the type which is manufactured in a basic square shape, having four side walls 12 , a top 14 , and a floor portion 16 . This example illustrates the shape of the bag before it is filled with product. [0051] However, as illustrated in FIG. 1B , the bulk bag 10 is filled with product, the bulk material naturally piles up inside the bag in a conical shape with equal forces in all directions. This equal force reshapes the bag side walls 12 above the square bottom 16 into a cylindrical shaped bag 18 . This causes a transitional area 17 that starts from the bottom 16 and ends when the bag has reached full cylindrical shape 18 . As seen in FIG. 1B , the floor portion 16 is much smaller than the cylindrical portion 18 . [0052] In the example given of a 37 inch (94 cm) square prior art bag, the floor portion 16 is 37 inches (94 cm) square but the cylindrical portion 18 is 47.1 inches (120 cm) in diameter. Or a little over 10 inches (25 cm) wider than the square base 16 of the bag 10 . The results that occur because of this difference is illustrated in FIGS. 2A and 2B . [0053] As illustrated in FIGS. 2A and 2B , areas 20 along the length of the bag 10 represent the unsupported columns of product within the bag and not illustrated. These areas 20 represent approximately 25% of the product within the bag 10 . As a result of this much unsupported weight in the unsupported columns 20 of product, this product, through the force of gravity, will seek a base and sag downwards until it reaches the floor 22 . In this example, the portions of the cylinder 18 that is unsupported, is shown as unsupported columns 20 of product. In this example the width of the unsupported columns 20 of product is approximately 5 inches (13 cm) (Arrows 69 ). [0054] An additional problem with the Prior Art Bags is illustrated in FIG. 3A through 3C . These three figures together illustrate the issue that unsupported columns of product create. [0055] FIG. 3A shows the initial condition of bulk bag 10 immediately after filling. It shows the space 21 between the floor 22 and the unsupported columns 20 of product. It depicts the initial height 63 of a recently filled bulk bag. [0056] FIG. 3B shows the condition of bulk bag 10 when it is able to settle in a perfectly vertical manner. As illustrated, the sidewall 12 is now partially vertical and partially horizontal. As a result the bag height 63 has now been reduced and is lower than original bag height. The new height is illustrated as 62 . However, since, in FIG. 3B , this has happened evenly around the entire base of the bag 10 , the cylindrical portion 18 of the bag 10 is still standing very vertically. [0057] FIG. 3C shows the condition of bulk bag 10 when it has any inertial force 19 such as transportation causing the bag to settle more in one direction than another. Bag height 63 is basically the same but the bag is no longer standing vertically. Bag bottom 16 is no longer centered beneath the bag (Arrow 65 ) as one bag side 12 has a much bigger portion (Arrow 67 ) laid horizontally. Since one side is now vertically shorter, the bag and product have moved into a leaning position. In this figure, a filled bag 10 which is typical of the current art, has a 37 inch (94 cm) square bottom 16 . The bag above has rounded out to a 47 inch (119 cm) cylinder 18 . The cylinder 18 has leaned to the right until the unsupported columns 20 of product are resting on the floor 22 below. To do this, it has used or converted part of side wall 12 to the bottom 16 . Such a bag is not only unattractive, it is less stable and less safe when being stacked upon. [0058] FIGS. 4A and 4B illustrate that the fully circular bottom bag 40 is somewhat uneconomical. Due to the weight that a bag must carry, the edges of the bottom panel are folded over to create the needed strength. Therefore, a panel that will fit a 47 inch (119 cm) diameter circle 44 must start out as a minimum square of fabric 66 that is 51 inches (130 cm) square. This allows for a 1.5 inch (3.8 cm) fold of fabric 42 and a 0.5 inch (1.3 cm) sew line 46 to create a 47 inch (119 cm) diameter bottom 45 that fits a 47 inch (119 cm) diameter circular wall 43 . [0059] In FIG. 4C a group of conventional bags 40 are illustrated, each filled with product. As seen in the figure, what has occurred to the bags shown in the figure was the result of the dynamics which occur in the prior art bags, as was previously illustrated in FIG. 3C and discussed above. These bags in FIG. 4C show the condition of bulk bag 10 being acted upon by inertial forces, causing the bag to settle more in one direction than another. Bag height is basically the same but the bag is no longer standing vertically. The bags 10 have rounded out to a cylinder 18 , which has caused the bags 10 to lean and sag until unsupported columns 20 of product are resting on the floor 22 below. To do this, it has used or converted part of side wall 12 to the bottom 16 . Such a bag is not only unattractive, it is less stable and less safe when being stacked upon. [0060] Having to start with a larger square of fabric requires, in this case, nearly 300 square inches (1935 square cm) of extra fabric cost. Additionally, as shown in FIG. 4B , it is difficult and time consuming to sew a circular seam. The sewing machines that are used in this industry to apply heavy load bearing seams 46 are designed to sew and move in a straight line. Therefore, the circular seam 46 is actually accomplished by making a large number of small straight lines 49 . 49 is intended to be the seam between the bottom and sidewalls of a prior art cylindrically shaped bag. However for clarity, the sew line is illustrated beyond the actual edge of the prior art bag. After each straight line, the operator must stop the machine and adjust the direction of fabric through the machine. This results in a comparatively slow production system with many stops as opposed to the square bag and the present invention. [0061] Turning to the present invention, reference is made first to FIGS. 5A through 11 . In FIG. 5A , there is illustrated a view of the bottom panel 68 that will become the bottom of the present invention. In this example, the beginning fabric is cut 48 inches (122 cm) square (Arrows 71 ). [0062] FIG. 5B shows that four triangular pieces 73 , in phantom view, must be either removed by cutting or folded to make an octagonal shape bottom 75 , having eight octagonal sides 81 , the bottom 75 being 48 inches (122 cm) across the vertical and horizontal centerline. [0063] FIG. 5C illustrates the final octagonal bottom 72 for the octagonal bag 80 . This final shape is created by folding the second stage of octagonal panel 70 1.25 inches (3.18 cm) on all eight sides 81 . When this is sewn to the side walls 12 with a 0.5 inch (1.3 cm) seam 76 , the result is the final octagonal bottom 72 that is 44.5 inches (113 cm) across the center lines in both directions. (Arrows 77 ) [0064] FIGS. 5A through 5C further illustrate how to make a perfectly uniform octagonal bag for bags with a perimeter of 148 inches (376 cm). It is obvious that this shaping of the bottom can be done for any perimeter size of bulk bag and gain the benefits already spoken of. In reality, what defines the invention of the octagonal bag disclosed herein, is that the octagonal shape of the bag defines a larger footprint for a filled bulk bag, and in doing so, eliminates the problems of sagging of filled bags which results in sidewalls becoming part of the support surface of the filled bags. In the octagonal bag, the larger footprint eliminates this problem, for the reasons as will be discussed below. [0065] As illustrated by FIG. 6 , a perfect octagon is not always preferred. When making a circular woven bag, it speeds production up to use the markings that already exist on the fabrics to indicate to the sewing machine operator when to make the turn for the next of the eight octagonal sides 81 . In this example, those pre-existing marks are at 16 inches (41 cm) (Arrows 82 ) and 21 inches (53 cm) (Arrows 84 ) apart. Modifying the octagonal bottom 72 to take advantage of these marks does not notably deteriorate the performance of this bag therefore, it is anticipated that many manufacturers will manufacture in this manner. [0066] Although the octagonal shape is the preferred embodiment of the bag, reference is made to FIG. 7 which shows a bag bottom 90 cut in a hexagonal shape 92 . The multi-sided bag, having six sides 94 , would perform similarly to the octagonal shaped bag 80 , and in fact it is foreseen that a bulk bag having multiple sides greater than four would, in theory, perform better than a prior art four sided bag. [0067] Returning to the preferred embodiment of the bulk bag illustrated in FIGS. 5A through 6 , using the same previously mentioned size bag of 37×37 inch (94×94 cm) square, what follows is a discussion of the mathematics used in this invention. For this size bag we recommend a finished Octagonal bottom panel 72 having centerline lengths of 44.6 inches (113 cm). These dimensions can obviously be altered to larger or smaller bags and larger or smaller centerline dimensions, but these are preferred dimensions. [0068] In order to end up with 44.6 inch (113 cm) centerline dimensions in both directions, a 48 inch (122 cm) piece of fabric is the preferred starting material. This piece of fabric has 2304 square inches (14,864 square cm) of area. This is 15% less materials than is required by the round bottom bag and 30% more than the bottom for the square bag. [0069] When this 44.6 inch (113 cm) Octagonal bottom 72 is sewn to the side walls 12 of a 37 inch (94 cm) square bag, it would have eight (8) 18.5 inch (47 cm) sides which add up to 148 inches (376 cm) of perimeter. This is identically equal to the perimeter of a 37 inch (94 cm) square bulk bag or a 47 inch (119 cm) diameter cylinder. [0070] The resulting bottom will then have 1646 square inches (10,619 square cm) of area to support the 1742 square inches (11,239 square cm) of cylinder above it. This works out to 94.5% of the total area of the cylinder above, which defines the larger footprint of the bag. [0071] In practical terms, the bag will have a slight bulge at the centerline of each side 12 of the original square based bag. This bulge is now only 1.25 inches (3.18 cm) beyond the base of the bag or 1.3% of the total product is bulging out beyond the base on each side. [0072] The average bulk bag carries 2200 lbs (998 kg). In the original square bag, the amount of unsupported product is 25% of the 2200 lbs (998 kg) or a total weight of 550 lbs (249 kg). As experienced in the industry, this is more than enough unsupported weight to influence the reshaping of the bulk bag. [0073] In the present invention, only 5.5% or 121 lbs (54.9 kg) of product is unsupported and that is divided up into 8 parts by the octagon instead of 4 parts for the prior art. Therefore, the imbalances in the octagonal shaped bag 80 have an average of only 15.1 lbs (6.85 kg) in any direction. This represents a less than 1% influence on the stability of the present invention. [0074] As to the cost of this bag, since the prior art uses 5 inches (13 cm) of sidewall to allow the bag to get to full support position, then the present invention can be made 5 inches (13 cm) shorter and hold the same amount of product. In the example explained above, there is a saving 5 inches (13 cm) of fabric on each of 4 sides of the original square bag for a total savings of 740 Square inches (4774 square cm) of side wall fabric. [0075] As was discussed earlier, the octagonal bottom 72 required a piece of fabric with an area of 2304 square inches (14,864 square cm) as opposed to the square bag bottom which required only 1764. However, since the octagonal bottom 72 allows the drop in side wall height of 5 inches (13 cm), we can see that the present invention uses an almost identical amount of fabric. The present invention uses 2304 sq. inches (14,864 sq. cm) for the bottom but saves 740 square inches (4774 sq. cm) on the side walls. This presents a net usage of 1564 square inches (10,090 sq. cm) for the present invention versus 1764 square inches (11,380 sq. cm) for the prior art. [0076] On the labor side, the sewing machine operator is still sewing the same 148 inches (376 cm) of perimeter bottom but is making 8 stops and turns instead of 4 stops and turns. The effect of this is minimal and probably equal in value to the 200 square inches (1290 square cm) of fabric that the octagonal bag saves over the prior art. [0077] As can now be seen, the octagonal bag 80 has a cost roughly equal to the prior art but has a greatly improved stability. [0078] The shape of the octagonal bottom 72 can be altered to accomplish different objectives without substantially affecting the stability. In one design, as seen in FIG. 6 , the sides of octagonal corners are altered to 16 inch (41 cm) corners and 21 inch (53 cm) sides. This alteration matches the marker yarns on circular reinforced fabrics and provides an easy visual aid for the sewing machine operators to know when to make the eight turns on the bottom to create the Octagonal shaped bottom. This speeds up the process and eliminates the need for marking the fabrics to identify the turning points. The inventor has used this method and found no identifiable deterioration in bag performance. [0079] FIGS. 8 through 11 illustrate the octagonal bags 80 filled with product resting on a conventional pallet 60 . As illustrated first in FIG. 8 , the single bag 80 , set upon a pallet 60 , provides an upright filled bag, wherein because of the large footprint of the bottom 90 , the sidewalls 81 have not bulged outward, as with the prior art bag shown in FIG. 2B . This due to the fact that the larger footprint of the bag 80 provides a broad, stable base upon which the filled bag 80 is supported, and in that manner, the sidewalls 81 are not inclined to sag and become part of the area upon which the product within the bag 80 rests, as in prior art bags, as seen in FIG. 2A . As seen in FIG. 9 , a pair of filled bags 80 are positioned side by side, with the sidewalls 81 of both bags supported in a vertical position, on the pallet 60 , and which therefore, continue to define a flat, horizontal top able to receive and support filled bags 80 in an upright position as seen in FIG. 11 . [0080] FIG. 10 illustrates an underside view of a filled octagonal shaped bag 80 , resting on a pallet 60 . From a comparison of this view with the prior art view as seen in FIG. 2 , it is clear that the sidewalls 81 of the bag 80 in FIG. 11 , although bulging out very slight, are still well confined within the footprint of the base or bottom 90 of the bag. Therefore the sidewalls 81 are unlikely to force the bag to sag, unlike the bag in FIG. 2B , where the sidewalls 12 have bulged out a great deal which results in sagging of bags, as seen in the bags illustrated in FIG. 4C . [0081] Now one can see that the wider base improves stability through providing a greater support surface, or a greater footprint, as it could be defined. We can also see that in the stacking of these bags, a similar top would also be beneficial as it will provide a greater surface for the upper bag to rest securely upon as well. However, it is not necessary to apply this design to the top to get the benefits of a bag that will stand stably by itself. [0082] It is also noted that providing a larger base, or footprint, through the use of the octagonal shaped bottom is beneficial for stacking. Therefore, using this technology to provide a larger panel on the top of the bag will provide a wider stacking surface for any bags being stacked on bags with octagonally shaped tops. This will further improve the stacking safety and stability of such bulk bags. [0083] The following is a list of parts and materials suitable for use in the present invention: [0000] PARTS LIST Parts Number Description 10 prior art bulk bag 12 side walls 14 top 16 floor portion 17 transitional area 18 cylinder shaped shape of bag 19 Inertial force 20 areas of unsupported columns of product 21 distance between floor and Product 22 floor 40 prior art bag 42 folded fabric 43 circular wall 44 full circle 46 sew line 50 bulk bag 52 floor portion 54 sides 55 wall portion 56 octagonal shape 58 triangles 59 corners 60 pallet 62 initial height of bulk bag 63 final height of bulk bag 64 transportation force 65 Arrows 67 Arrows 66 51 inch (132 cm) Fabric square 68 beginning octagon bottom panel 70 second stage of octagon panel 71 Arrows 72 final octagon bottom panel 73 triangular portions 74 1.25 inch (3.18 cm) fabric fold 75 octagonal shape 76 seam 0.5 inches (1.3 cm) deep 77 Arrows 80 octagonal bag 81 sides 82 Arrows 84 Arrows 90 hexagonal bag bottom 92 hexagonal shape 94 sides [0084] All measurements disclosed herein are at standard temperature and pressure, at sea level on Earth, unless indicated otherwise. All materials used or intended to be used in a human being are biocompatible, unless indicated otherwise. [0085] The foregoing embodiments are presented by way of example only; the scope of the present invention is to be limited only by the following claims.
A fabric bulk bag and a method for constructing the same, the bag including a continuous sidewall, a top portion, and a bottom, all defining a bulk storage space therein; the bottom further comprising eight sides which define an octagonal shape having an enlarged footprint so that the bag wall is sewn to the bottom in less time than a round shaped bag, yet when filled stands more upright with less tendency to lean than the current square shaped bags thereby providing a safer more dependable stacking bulk bag. In the method of producing the fabric bulk bag, the bag is constructed in less time than the prior art round bottom bags, uses less wall fabric than prior art square bottomed bags and when constructed and filled, supports itself more stable on a floor or pallet because it provides substantially more base for the product to rest on. In other embodiments, the bag would be multi-sided with greater than four sides.
3
CROSS-REFERENCE TO RELATED APPLICATION [0001] This application is a Continuation of U.S. patent application Ser. No. 14/204,758 filed on Mar. 11, 2014, which claims priority to U.S. Provisional Patent Application No. 61/788,191, filed Mar. 15, 2013, wherein the contents of each of the foregoing is incorporated herein in its entirety by reference. BACKGROUND OF THE INVENTION [0002] Hoses, such as hydraulic hoses, are subject to pressure in use and may break if worn or the pressure is too high. When a hose breaks, high pressure fluid may erupt from the breakage site and travel at high speed in a continuous stream. This high pressure stream may have a large amount of kinetic energy across a small cross sectional area, which in turn may cause injury to people, equipment, and the environment. In some embodiments, sleeves of the present invention may be used to protect against injury from such breakages. SUMMARY OF THE INVENTION [0003] In one embodiment, the invention includes a burst protection sleeve having an inner sleeve and an outer sleeve. In addition, the inner sleeve and the outer sleeve are joined and the inner sleeve is disposed within the outer sleeve. [0004] In another embodiment, the present invention includes a burst protection system. The system includes a burst protection sleeve having an inner sleeve and an outer sleeve. In addition, the inner sleeve and the outer sleeve are joined and the inner sleeve is disposed within the outer sleeve. The system further includes a hose and the burst protection sleeve is positioned to surround at least a portion of the hose. [0005] In still another embodiment, the present invention includes a method for installing a burst protection sleeve. The method includes positioning a burst protection sleeve around a hose, wherein the burst protection sleeve includes an inner sleeve and an outer sleeve. In addition, the inner sleeve and the outer sleeve are joined and the inner sleeve is disposed within the outer sleeve. Furthermore, in this embodiment, the burst protection sleeve is positioned around the hose in a manner to leave a space between the hose and the inner sleeve. [0006] The following description illustrates one or more embodiments of the invention and serves to explain the principles and exemplary embodiment of the invention. BRIEF DESCRIPTION OF THE DRAWINGS [0007] These and other features, aspects, and advantages of the present invention are better understood when the following Detailed Description is read with reference to the accompanying drawings, wherein: [0008] FIG. 1 is a partial cutaway perspective view showing an embodiment of a sleeve of the present invention; [0009] FIG. 2 is an end view showing the embodiment of the sleeve of FIG. 1 ; and [0010] FIG. 3 is an end view showing the embodiment of the sleeve of FIG. 1 installed in an exemplary manner upon a hose. DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS [0011] Reference will now be made in detail to exemplary embodiments of the present invention, one or more examples of which are illustrated in the accompanying drawings. Each example is provided by way of explanation of the invention and not by limitation of the invention. It will be apparent to those skilled in the art that modifications and variations can be made in the present invention without departing from the scope or spirit thereof. For instance, features illustrated or described as part of one embodiment may be used on another embodiment to yield a still further embodiment. Thus, it is intended that the present invention covers such modifications and variations as come within the scope of the appended claims and their equivalents. [0012] In one embodiment, the present invention includes a burst protection sleeve. Hoses, including high pressure hoses, pose the risk of injury upon breakage or leaking. By way of example, a pinhole leak may create a fast-moving stream that may be capable of penetrating the human skin, causing serious injury or death. Sleeves of the current invention may be placed around or upon a hose and, upon breakage or leaking of the hose, the kinetic energy of the fluid in the hose is both absorbed by and deflected by the sleeve. In addition, sleeves of the present invention may channel fluid from the hose to a single location, thereby simplifying removal of the leaked fluid. Sleeves of the present invention also provide an abrasion resistance to an underlying hose. [0013] FIG. 1 depicts an exemplary embodiment of a sleeve of the present invention. As shown, sleeve 100 is shown as applied to an underlying hose (shown in broken lines). In the depicted embodiment, sleeve 100 includes inner sleeve 102 (shown by a partial cutaway), outer sleeve 104 , and hollow interior 106 . Hollow interior 106 is depicted in a generally circular or tubular shape, but other shapes are also within the scope of the present invention. Furthermore, in some embodiments, sleeve 100 may be flexible and capable of configuring to different shaped hoses. In addition, when not in use, sleeve 100 may be collapsible. In some embodiments, as shown in FIG. 1 , inner sleeve 102 and outer sleeve 104 may be joined, such as by seam 108 . Although two seams 108 are shown in the embodiment of FIG. 1 , other embodiments may have one seam and still other embodiments may have three seams, four seams, or greater than four or more seams. Furthermore, although only one inner sleeve 102 and one outer sleeve 104 are shown in the depicted embodiment, alternative embodiments may have additional sleeves disposed between and joined with inner sleeve 102 and outer sleeve 104 . Furthermore, as shown in FIG. 2 , seam 108 may form channel 110 in some embodiments of the present invention. [0014] The sleeves of the present invention may be made from any material or combination of materials suitable for a particular sleeve's intended purpose. In some embodiments, materials for sleeves may be selected to result in an inner sleeve or an outer sleeve with high tensile strength, high thermal resistance, high abrasion resistance, high fatigue resistance, and/or high chemical and heat stability. By way of example, and without limitation, inner sleeves and outer sleeves may be composed of any natural or synthetic material known in the art. In one embodiment, inner sleeves and/or outer sleeves may include fibers such as meta-, para-aramid fibers, para-aramid fibers, meta-aramid fibers, cotton, rayon, Teflon®-coated fibers, shaped fibers, glass fibers, basalt fibers, carbon fibers, high modulus polyethylene fibers, liquid crystal polymer fibers, hollow fibers, nylon, polyesters, polypropylene, polyethylene, polyphenylene sulfide, polyetheretherketone, polyolefins, amide polymers or copolymers, carbon fibers, polyvinyl alcohol fibers, or combinations thereof. In addition, inner sleeves and outer sleeves of the present invention may have the same or different compositions. In some embodiments, inner sleeves and/or outer sleeves may be comprised of materials that are generally impenetrable to fluids within the temperature and pressure ranges of fluids present in the underlying hoses or tubes used in conjunction with a sleeve. [0015] In some embodiments, inner sleeves and outer sleeves of the present invention may be comprised of yarn of any denier that is suitable to withstand the potential pressure exposure of a given application. In some embodiments, sleeves of the present invention may be prepared using warp yarn that is greater than 2700 denier. In some embodiments, warp yarn having about 2700 denier may be used. Some embodiments of the present invention may comprise warp yarn in the range of about 840 denier to about 2700 denier. In still other embodiments, sleeves of the present invention may comprise warp yarns in the range of about 2700 denier to about 5000 denier. By way of further example, some inner sleeves of the present invention comprise warp yarn of at least about 2000 denier, and some outer sleeves of the present invention comprise warp yarn of at least about 2500 denier. In some embodiments, yarns having less than 3000 denier may be used. In some embodiments, fill yarns may be used within the range of about 500 to about 1000 denier, including each intermittent value therein. [0016] In some embodiments, inner sleeves and outer sleeves of the present invention may comprise material that is woven, such as woven yarn, fibers, or other material suitable for the intended purpose of the sleeve. The term “woven”, as used herein, means interlacing individual fibers in a regular order. Any method of weaving known in the art may be utilized in connection with the present invention. Similarly, any weave pattern known in the art may be utilized in the webbing, including, but not limited to, a plain weave, a twill weave, a satin weave, a tabby weave, a taffeta weave, a matt weave, a basket weave, a rib weave, computer-generated interlacings, and combinations thereof. [0017] In addition, the fibers employed may have any configuration known in the art. For example, the fibers may be configured as circular, ovular, elliptical, or flat. In addition, in some embodiments, some or all material used to form an inner sleeve and/or an outer sleeve of the present invention may be twisted (i.e., the fiber is twisted about its central axis) prior to being woven into an inner sleeve or an outer sleeve. [0018] In one embodiment, an inner sleeve may have a tight plain weave, such as in the range of about 4.75 picks per inch to about 50 picks per inch, including each intermittent value therein. In some embodiments, an inner sleeve may have a pick count of at least about 17.5 picks per inch. An outer sleeve may have a plain weave of about 2.5 to about 7.5 picks per inch, including each intermittent value therein. In some embodiments, an outer sleeve may have a pick count of at least about 12.5 picks per inch. In some embodiments, an inner sleeve may have material woven using a plain weave and an outer sleeve may have material woven using either a twill weave or a plain weave. For reference, a plain weave may also be referred to as a basket weave. [0019] By way of example, in one exemplary embodiment of the present invention, a sleeve may have an inner woven tube comprised of twisted 1000 denier 2-ply polyester warp yarn and an outer woven sleeve comprised of 2700 denier bulk nylon warp with a pick count of 22.5 picks per inch, wherein 840 denier nylon is employed as fill yarn (also called weft). In some embodiments, suitable yarn may be woven to result in sleeves that may withstand a burst resulting in at least 20,000 pounds of pressure against the sleeve. [0020] Any suitable process may be employed to prepare embodiments of the present invention. In some embodiments, an inner sleeve and an outer sleeve may be joined together during a weaving process by using a latching needle to knit the fibers of the inner tube and the fibers of the outer tube together at one or more edges, such as to form a seam such as seam 108 shown in FIG. 2 . [0021] Embodiments of sleeves of the present invention may be made using materials that provide adequate strength to avoid bursting from a leak or breakage of the underlying hose or tube as well as providing for abrasion resistance properties to the sleeves. For certain embodiments, sleeves may also be comprised of materials that are resistant to degradation from fluids present in the hoses or tubes with which the sleeves are used. [0022] Sleeves of the present invention may optionally be secured to hoses or tubes using any suitable means, such as plastic ties, metal clamps, and the like. In some embodiments, such securing mechanisms may be configured or attached in a manner to enable any fluid to escape from the sleeve upon any release from an underlying hose or tube. In some embodiments, a sleeve may be used to house a single hose or tube. In other embodiments, a sleeve may be used to house a plurality of hoses or tubes. [0023] In some embodiments, a space or gap may be present between an inner sleeve of the present invention and an underlying hose or tube. The space may not be present or apparent when the sleeve is collapsed around a hose, but the space is present and exists such that it may be filled with fluid upon any leakage from the underlying hose. In this manner, sleeves of the present invention may be sized or applied to hoses in a manner such that a space remains between the inner sleeve and/or the outer sleeve and a sleeved hose, i.e., providing a sufficiently loose fit between the inner sleeve and the outer sleeve. In some embodiments, such a space may be at least about 0.25, 0.50, 0.75, or 1.0 inch, including each intermittent value therein. In some specific embodiments, the space between the inner sleeve and the underlying hose is at least 0.50 inches. In addition, channels may be present within sleeves of the present invention, such as channel 110 , to permit fluid escaping from a hose within the sleeve to flow. [0024] As indicated above, sleeves of the present invention may be used to deflect fluid upon release from an underlying hose or tube and may also channel such fluid in the direction of the sleeve. By way of example, upon a leak in an underlying tube, a sleeve of the present invention may block the escaping fluid and redirect that fluid in a direction parallel to the length of the sleeve. Such fluid may travel in any space between the inner sleeve and the underlying tube, between any space between the inner sleeve and the outer sleeve if the fluid penetrates through the inner sleeve, and/or along channel 108 formed by any seams in a sleeve. In some embodiments, an inner sleeve may be provided with a rib or a spacer. Such a rib may provide a space, or channel, between an underlying hose or tube and an inner sleeve such that any fluid escaping from the hose may be redirected to flow parallel with the length of the inner sleeve in such space formed by a rib. In addition, a seam may be configured in some embodiments to provide a space between an underlying hose and the inner sleeve. In still other embodiments, an inner sleeve having a sufficiently larger inner diameter as compared with the outer diameter of an underlying hose may be employed to ensure an adequate space or gap between the hose and inner sleeve. In some embodiments, the space or gap may be present around the entire underlying hose. In some embodiments, although an inner sleeve may rest against a hose during normal operation, the inner sleeve is sufficiently loose around the hose such that the sleeve may be displaced to form a space or gap upon a burst or leak in the underlying hose. [0025] In some embodiments, sleeves of the present invention may be configured to provide an indication of wear in the sleeve. By way of example, an outer sleeve and an inner sleeve of a particular sleeve may have different or visually-contrasting colors. In one embodiment, an outer sleeve may be black or another dark color and an inner sleeve may be a bright color, such as bright yellow. Upon wear of the outer sleeve, the bright color of the inner sleeve will be visible, thereby indicating to a user that the sleeve is damaged, thin, ripped, or torn. Such indicators enable a user to change the sleeve before further damage is incurred and before a sleeve becomes unsuitable for use. Sleeve Performance Testing [0026] Performance of an embodiment of a sleeve of the present invention was tested using the following procedures. The tested sleeve included an outer sleeve prepared from 2700-denier nylon yarn and an inner sleeve with twisted 1000-denier polyester yarn, both having 2×840-denier nylon fill yarn woven at 90 picks/inch. The loom used in the weaving process inserted fill yarn with a needle from one side of the machine and, when the needle reached the other side of the machine, the filling yarn was grabbed and knitted into the other side of the webbing. This technique actually weaves 2 filling ends for every pick woven. [0027] For the testing, the sleeve, having the additional parameters identified in Table 1 for each individual test, was clamped at each end upon a hose measuring two feet in length and having the parameters identified in Table 1 corresponding to the particular test. An end of each hose was plugged and the other end was connected to an air-over-water intensifier. Air was initially bled from the hose and then the pressure inside the hose was increased until the hose failed. Testing was conducted at an ambient temperature of approximately 70° F. and, after hose failure, the maximum pressure recorded by the process meter was recalled and recorded. Observations concerning the performance of the sleeve were also recorded. The results are set forth in Table 1, wherein size indicates the inner diameter of the hose in units of 1/16 inches, “OD” indicates outer diameter, “ID” represents inner diameter, “MSHA” indicates Mine Safety Health Administration standards, and references beginning with “100W” indicate standards of SAE International. [0028] Based upon the test results, it is believed that sleeve embodiments providing a space or gap between the outer surface of a sleeved hose and the inner face of an inner sleeve may provide advantageous performance in some embodiments. In this regard, some embodiments of the present invention provide a space or gap of at least 0.5 inches between an inner sleeve and a hose. [0029] These and other modifications and variations to the present invention may be practiced by those of ordinary skill in the art without departing from the spirit and scope of the present invention, which is more particularly set forth in the appended claims. In addition, it should be understood that aspects of the various embodiments may be interchanged in whole or in part. Furthermore, those of ordinary skill in the art will appreciate that the foregoing description is by way of example only, and it is not intended to limit the invention as further described in such appended claims. Therefore, the spirit and scope of the appended claims should not be limited to the exemplary description of the versions contained herein.
A sleeve, which may be used to protect against bursting from hydraulic or other pressurized hoses and tubes, is disclosed. A method of installing such sleeves and a burst protection system are also disclosed.
8
CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application is a continuation of co-pending PCT patent application No. PCT/DK2011/050241, filed Jun. 27, 2011, which claims the benefit of Danish patent application serial number PA 2010 70300, filed Jun. 29, 2010 and U.S. provisional patent application Ser. No. 61/359,629, filed Jun. 29, 2010. Each of the aforementioned related patent applications is herein incorporated by reference in its entirety. FIELD OF THE INVENTION [0002] This present invention relates to a permanent magnet (PM) generator inductance profile identification by using the stator flux or stator current vector control loop. BACKGROUND OF THE INVENTION [0003] PM generators, and in particular interior permanent magnet (IPM) generators, have the advantage of high power conversion efficiency and robust mechanical structure. [0004] Loading a PM generator with an electrical power of desired value and quality can have two issues: 1. The parameters of the generators could be inconsistent from the designed value and deviate from manufacturer to manufacturer, and 2. Parameters like machine inductances are heavily dependant on the machine loading conditions. [0007] In particular, load dependent machine inductances make it difficult to achieve optimized efficiency during operation. Moreover, system stability could be greatly affected if the generator parameter deviates too far away from its designed value. [0008] Thus, there is a need for an on-the-fly determination of the generator parameters, in particular an on-the-fly determination of machine inductance profiles. [0009] It may be seen as an object of embodiments of the present invention to provide a method for on-the-fly generator inductance profile identification by using the stator flux or stator current vector control loop. DESCRIPTION OF THE INVENTION [0010] The present invention relates to a new approach for PM generator inductance profile identification by using the stator flux or stator current vector control loop. [0011] The advantages of the proposed solution according to the present invention are: 1. The invention mitigates the risk of power control instability due to mismatched machine parameters from the nominal value given by the machine designers. 2. The invention effectively tracks the generator inductance for all operating conditions along the power curve. This makes the electrical power loading reliable irrespective of the generator type and independent of the operating condition. 3. The method according to the present invention can be used to evaluate the machine design and give valuable feedback to improve the generator design. 4. The method for stator inductance identification according to the present invention is general and can be applied for both surface mount permanent magnet (SPM) generator and interior permanent magnet (IPM) generator since the same flux observer and current measurement could be applied for both SPM and IPM. SPM can be treated as IPM machine with very small saliency ratio. 5. The method according to the present invention can be applied for both stator flux vector control system and stator current vector control system. For both control systems, a voltage mode stator flux observer is applied so that the effect of inaccurate stator inductance value used in control is eliminated in the identification process. 6. The proposed stator inductance profile identification method according to the present invention may be implemented as a software algorithm which can be easily integrated into the converter start-up process without extra hardware cost. 7. A simple and reliable sinusoidal response amplitude measurement method is proposed to avoid using FFT or complicated peak-detection algorithm. 8. The effect of stator inductance variation due to magnetic circuit saturation at high current can be eliminated by applying the identification results in control, which makes it possible to achieve stable and optimized control performance even for IPM with high saliency ratio. [0020] Accurate stator flux estimation is possible using current mode stator flux observer after stator inductance profile has been identified and applied. This makes it possible to apply stator flux control at extremely low speed in WTG direct drive application. [0021] Thus, in a first aspect the present invention relates to a method for determining an inductance of a PM machine during operation of said PM machine, the method comprising the steps of: a) operating a PM machine within a predetermined rotational speed window, b) ramping up a DC level of a first reference signal until a desired first current level has been reached, c) computing a DC level of a second reference signal using voltage limiting constraint to ensure sufficient field weakening current is provided in the process of the DC level ramping up of the first reference signal, d) adding a first time dependent AC test signal on the DC level of both the first reference signal and the second reference signal, e) computing a first self-saturation induced inductance value in response to the applied first time dependent AC test signal, and storing said first self-saturation induced inductance value in suitable memory means, f) computing a first cross-saturation induced inductance value in response to the applied first time dependent test signal, and storing said first cross-saturation induced inductance value in the memory means, g) removing the first time dependent AC test signal, h) repeating steps b)-g) until the self-saturation induced inductance and the cross-saturation induced inductance have been calculated and stored for a predetermined number of first current levels, and i) removing the first time dependent AC test signal, and ramping down the DC level of the first reference signal to zero. [0031] The method according to the first aspect may further comprise the steps of: a) ramping up the DC level of the first and second reference signals until desired current levels have been reached, b) adding a time dependent AC test signal on the DC level of both the first reference signal and the second reference signal, c) computing a second self-saturation induced inductance value in response to the applied second time dependent AC test signal, and storing said second self-saturation induced inductance value in the memory means, d) computing a second cross-saturation induced inductance value, in response to the applied second time dependent AC test signal, and storing said second cross-saturation induced inductance value in the memory means, e) removing the second time dependent AC test signal f) repeating steps c)-e) until the self-saturation induced inductance and the cross-saturation induced inductance have been calculated and stored for a predetermined number of second current levels, and g) removing the second time dependent AC test signal, and ramping down the DC reference signals to zero. [0039] The DC reference signals with AC signal added may be converted to stator flux reference signals using the nominal Ld and nominal Lq inductance when the method is applied to PM generator controlled by a stator flux controller. [0040] Alternatively, the DC reference signals with AC signal added may be stator current reference signals when the method is applied to a PM generator controlled by the stator current controller. [0041] The stator inductance identification may be implemented as part of the PM generator start-up process before a power control loop is closed. The same stator flux controller or the stator current controller may be operated in the normal power control mode after the stator inductance identification is completed. [0042] A voltage mode stator flux observer may be applied to obtain the stator flux signal in stator inductance identification process for both stator flux control system and stator current control system. [0043] The self-saturation induced q-axis (or d-axis) stator inductance value may be computed as the ratio of the AC response of q-axis (or d-axis) stator flux signal and the AC response of the corresponding q-axis (or d-axis) stator current signal at a predetermined number of DC levels of q-axis (or d-axis) current with d-axis (or q-axis) current DC level set closer to zero. [0044] Similarly, the cross-saturation induced q-axis (or d-axis) stator inductance value may be computed as the ratio of the AC response of q-axis (or d-axis) stator flux signal and the AC response of the corresponding q-axis (or d-axis) stator current signal at a predetermined number of DC levels of d-axis (or q-axis) current with q-axis (or d-axis) current DC level set closer to zero. [0045] In the stator inductance identification process, the corresponding stator currents may be driven from low current level to high current level by the corresponding DC reference signals so that the entire operation current range of PM generator may be covered in the inductance profile identification process. [0046] The stator inductance identification may be carried out in the predetermined rotational speed window. The speed should be chosen high enough to ensure the stator flux obtained from voltage mode stator flux observer is accurate and to allow large current applied in stator inductance identification process without exceeding the mechanical torque limit. The speed should be chosen to be lower than the field weakening operation speed of PM machine and in the mean while to allow large stator current applied in identification process without exceeding the power limit of generator control system. [0047] In an embodiment of the method according to the present invention, the time dependent AC test signal added to the DC reference signals is a sinusoidal signal of fixed frequency. However, other types of time dependent AC test signal like square signal or triangle signal of fixed frequency may be applied as excitation signal as well. The frequency of the AC test signal is chosen in the range from 30 Hz to 100 Hz to minimize undesired low frequency torque ripple induced in inductance identification process. For reliable computation of inductance value, the frequency of the AC testing signal should be set below the bandwidth of the corresponding stator flux controller or the stator current controller to ensure sufficient AC response on stator current and stator flux. The amplitude of the AC test signal is chosen so that the AC current response is around 10% to 20% of the rated current of the machine. [0048] In a embodiment, the AC response amplitudes of the stator flux and stator current may be computed from the orthogonal signal generated by the resonant filter at the injection frequency and a 900 phase shift filter. The DC component of stator flux and stator current may be removed by the resonant filter. However, other AC response amplitude measurement method can also be used for the same purpose. [0049] The predetermined numbers of first and second current levels may be decided by the desired resolution of stator inductance profile, the stator current range for inductance identification and time spending on stator inductance identification. Normally, 4 to 10 current level should be sufficient. [0050] The first desired current may correspond to q-axis stator current, and the second desired current may correspond to d-axis stator current. Accordingly, the first DC reference is corresponding to a q-axis stator current reference, and the second DC reference is corresponding to a d-axis stator current reference. Therefore, the first self-saturation inductance value stored is corresponding to a point in q-axis stator inductance “Lq” profile with respect to a DC level of q-axis current, and the second self-saturation inductance value stored is corresponding to a point in d-axis stator inductance “Ld” profile with respect to a DC level of d-axis current. Similarly, the first cross-saturation inductance value stored is corresponding to a point in d-axis stator inductance “Ld_CC” profile with respect to a DC level of q-axis current and the second self-saturation inductance value stored is corresponding to a point in q-axis stator inductance “Lq_CC” profile with respect to a DC level of d-axis current, [0051] Determined stator inductance profile data may be processed either on-line or off-line to obtain the stator inductance functions with respect to its self-saturation current and its cross-saturation current. The stator inductance functions thus obtained can be applied in the generator power control to optimize the control performance of PM machine for both stator flux control system and stator current control system. The stator inductance function can be applied to improve the accuracy of the current mode stator flux observer for the stator flux control system to improve its performance at low speed heavy load operation. [0052] In a second aspect the present invention relates to a computer program product for carrying out the method according to any of the preceding claims when said computer program product is run on a computer. BRIEF DESCRIPTION OF THE DRAWINGS [0053] The present invention will now be explained in further details with reference to the accompanying drawings. [0054] FIGS. 1A , 1 B, and 1 C illustrate inductance profile identification of a PM generator controlled applied to the stator flux vector feedback system. [0055] FIGS. 2A , 2 B, and 2 C illustrate inductance profile identification of a PM generator controlled applied to the stator current vector feedback system. [0056] FIG. 3 shows a sinusoidal response amplitude measurement method using a resonant filter and 900 phase shift filter for a fixed signal frequency. [0057] FIGS. 4A and 4B show a generalized procedure for stator inductance profile identification. [0058] FIG. 5 illustrates the measured stator current and estimated stator flux signal responses of an IPM machine in the stator inductance identification process. [0059] FIG. 6 illustrates the measured stator flux and stator current signal responses of an IPM machine in the process of identification of self-saturation induced “Lq” inductance value and cross-saturation induced “Ld” inductance value at a testing current level ISQ=ISQ_test and ISD≈0. [0060] FIG. 7 illustrates the measured stator flux and stator current signal responses of an IPM machine in the process of identification of self-saturation induced “Ld” inductance value and cross-saturation induced “Lq” inductance value at a testing current level ISD=ISD_test and ISQ≈0 [0061] While the invention is susceptible to various modifications and alternative forms, specific embodiments have been shown by way of examples in the drawings and will be described in detail herein. It should be understood, however, that the invention is not intended to be limited to the particular forms disclosed. Rather, the invention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims. The application of this invention is not limited to a wind turbine generator machine but extends to the low speed high torque applications like lifts and conveyors that employ PM machines which normally operate at motoring mode operation. DETAILED DESCRIPTION OF THE INVENTION [0062] An embodiment of the present invention describes a simple method for IPM machine inductance profile identification based on voltage mode stator flux observation which could be easily applied in wind turbine application for both stator flux vector feedback control system and current vector feedback control system. [0063] The foundation of the proposed method is the stator flux equation in rotor flux reference d-q frame as described using equation (1) and (2). [0000] ψ sd =L d ( i sd ,i sq )* i sd +ω r   (1) [0000] ψ sq =L q ( i sd ,i sq )* i sq   (2) [0064] The stator inductance due to self-saturation effect at d-axis stator current level (denoted as “ISD_Test”) and q-axis stator current level (denoted as “ISQ_Test”) can be obtained from equation (3) and equation (4). [0000] L d  ( i sd , i sq ≈ 0 ) = ∂ ψ sd ∂ i sd  isd = ISD_Test ( 3 ) L q  ( i sd ≈ 0 , i sq ) = ∂ ψ sq ∂ i sq  isq = ISQ_Test ( 4 ) [0065] Similarly, the stator inductance due to cross saturation effect can be obtained as: [0000] L d_CC  ( i sd ≈ 0 , i sq ) = ∂ ψ sd ∂ i sd  isq = ISQ_Test ( 5 ) L q_CC  ( i sd , i sq ≈ 0 ) = ∂ ψ sq ∂ i sq  isd = ISD_Test ( 6 ) [0066] FIGS. 1A-1C and FIGS. 2A-2C illustrate the PM generator stator inductance identification schemes for the stator flux vector feedback control and stator current vector feedback control system, respectively. [0067] Machine parameter identification method is independent of the control strategy employed. [0068] For both stator flux control system and the stator current feedback control system, the stator inductance profile identification is performed by using stator flux estimation results obtained from the voltage mode stator flux observer which is insensitive to stator inductance variation. The stator inductance profile identification is carried out in a proper speed window. The speed should be high enough to ensure reliable and accurate estimation of stator flux from voltage mode stator flux observer and to avoid exceeding the torque limit of the generator system when high current is applied in identification process. The speed should not be too high to allow sufficient high current to be applied in identification process without exceeding the maximum power limit of the generator system. If possible, the speed window should be set below the field weakening operation speed so that the q-axis stator current can be driven to sufficiently high level to test the saturation effect of the generator with d-axis stator current closer to zero. [0069] The stator inductance profile identification is primarily carried out in a high speed window with voltage mode stator flux observer applied. However, it has to be noted that, in normal power production control, the stator inductance identification results are applied to improve the control performance in both light and heavy loading conditions. In practice, on-line or off-line processing of the identified stator inductance profile is carried out so that the stator inductance can be represented as a function of the corresponding self-saturation current and cross-saturation current for this purpose. [0070] When the stator inductance identification is implemented in the stator flux control system as shown in FIGS. 1A-1C (which are logically connected through connections A 1 -A 6 and B 1 -B 9 ), the stator flux reference generation block and stator inductance computation block are activated together with the stator flux controller block. The generator power is directly controlled from the generated stator flux references. The current reference signals for magnet field power generation (denoted as “IS_FP_REF”) and demagnetization (denoted as “IS_MAG_REF”) with sinusoidal test signal injected are converted to the flux reference signals (denoted as “flux_FP_REF” and “flux_MAG_REF”) using nominal Ld and nominal Lq value. The resulting flux reference signals are fed into the voltage limiting based field weakening block. The sinusoidal stator flux reference signal is thus injected into stator flux control system of PM machine. The stator flux reference signals are then fed into the stator flux reference correction proportional-integral (PI) controller. The resulting stator flux references after correction control are then converted to stationary reference frame. The output of stator flux vector controller is voltage reference signals which is fed into the PWM modulator. The converter gating signal is generated by the PWM modulator. Finally, the stator flux vector feedback control loop is closed in stationary reference frame using the observed stator flux feedback signal. The stator inductance value is computed using the measured stator current signal and the observed stator flux signal in the stator inductance computation block. In this block, the stator flux signal and stator current signal are first transferred to the rotor flux d-q reference frame. Afterwards, the sinusoidal response amplitude of both stator flux signal and stator current signal are extracted. Lastly, the stator inductance is computed as the ratio the sinusoidal response amplitude of stator flux signal vs. stator current signal. The sinusoidal response amplitude of the stator current signal is limited to be above 1 uA to avoid divided-by-zero issue in the ratio computation. [0071] When the stator inductance identification is implemented in the stator current control system as shown in FIGS. 2A-2C (which are logically connected through connections C 1 -C 4 and D 1 -D 4 ), the stator current reference generation block and stator inductance computation block are activated together with the stator current controller. The generator power is directly controlled by the generated current references. The current reference signals with sinusoidal test signal injected are fed into the voltage limiting based field weakening block. The sinusoidal stator current reference signal is thus injected into stator current control system of PM machine. The stator current vector feedback control is closed with the measured stator current feedback signal in rotor flux reference d-q frame. The stator voltage signals are then converted into stationary reference frame and fed into PWM modulator. For the stator current control system, the voltage mode stator flux observer is implemented in the stator inductance computation block. The rest part of the stator inductance value computation is same as the stator flux control system. [0072] More detailed description of the station inductance identification method is given below. [0073] The method according to the present invention uses the flux/current closed loop control to ramp up/down the d-axis or q-axis stator current to the desired DC amplitude level by changing the stator flux/current reference signal while monitoring the measured corresponding d-axis or q-axis stator current. [0074] In the process of ramping up/down the q-axis stator current DC level, voltage limiting constraint is applied to avoid the PWM modulator working in non-linear modulation range by providing sufficient d-axis weakening field current if necessary at high speed in stator inductance identification process. For simplicity, in the process of ramping up/down the d-axis stator current level, the q-axis stator flux/current reference is set to zero since in this case the voltage limiting constraint is naturally satisfied. [0075] When the desired d-axis or q-axis stator current level is reached, a fixed frequency sinusoidal stator flux/current reference disturbance signal of small amplitude is injected into the stator flux/current control system. The corresponding d-axis or q-axis stator inductance including the self-saturation effect and cross-saturation effect is then computed using equation (7) to (10) from the sinusoidal response of the corresponding stator flux and stator current signals. [0000] L d  ( i sd , i sq ≈ 0 ) = FLUX_D  _AC  _AMP ISD_AC  _AMP  i sd = ISD_TEST ( 7 ) L q_CC  ( i sd , i sq ≈ 0 ) = FLUX_Q  _AC  _AMP ISQ_AC  _AMP  i ssd = ISD_TEST ( 8 ) L q  ( i sd ≈ 0 , i sq ) = FLUX_Q  _AC  _AMP ISQ_AC  _AMP  i sq = ISQ_TEST ( 9 ) L d_CC  ( i sd ≈ 0 , i sq ) = FLUX_D  _AC  _AMP ISD_AC  _AMP  i sq = ISQ_TEST ( 10 ) [0076] For both stator flux vector control and stator current vector control, the voltage mode stator flux observer is used for stator inductance estimation. The principle behind voltage mode stator flux observation is represented as equation (11) and (12) in stator stationary α/β reference frame. [0000] ψ sα =∫( U sα −Rs*i sα ) dt   (11) [0000] ψ sβ =∫( U sβ −Rs*i sβ ) dt   (12) [0077] To simplify the implementation, the stator voltage command signals U* sα ,U* sβ (PWM modulator input signals) could be used as stator voltage signals for voltage mode stator flux observation. [0078] Various known techniques could be used to eliminate the integration drifting due to DC offset of stator current measurement of voltage mode stator flux observer and to minimize the effect of the control quantization error. One possible approach that can achieve this purpose is the adaptive low pass filter based voltage mode flux observer given in equation (13) and (14), where, “V_VM” is a coefficient to shape the low pass filter magnitude response at low frequency range and ω em is the rotor electrical angular speed estimated from encoder position measurement. [0000] ψ s   α = ( u s   α * - Rs * i s   α ) + K_VM * ( u s   β * - Rs * i s   β ) s + ω em * K_VM ( 13 ) ψ s   β = ( u s   β * - Rs * i s   β ) - K_VM * ( u s   α * - Rs * i s   α ) s + ω em * K_VM ( 14 ) [0079] The output stator flux vector Ψ sα ,Ψ sβ from voltage mode stator flux observer is transferred to the rotor flux reference DQ reference using equation (15) and (16), where θ em is the electrical angle of rotor flux with respect to the α-axis of the stator stationary reference frame. [0000] ψ sd =ψ sα *cos θ em +ψ sβ *sin θ em   (11) [0000] ψ sq =ψ sα *sin θ em +ψ sβ *cos θ em   (12) [0080] For the stator flux vector control based control scheme, the stator flux reference vector is generated by applying the voltage limiting constraint described in equation (17), where “modu_max” is the maximum allowed PWM modulation index, “Udc” is the DC link voltage signal. The Input signal is the field power stator flux reference (denoted as FLUX_FP_REF) signal. The output signal is the stator magnetization flux reference (denoted as FLUX_MAG_REF). [0000] FLUX_MAG  _REF = min ( ψ r , ( mod   u_max * U dc 3 * ω em ) 2 - ( FLUX_FP  _REF ) 2 ) ( 17 ) [0081] For the stator current vector control based control scheme, the stator current reference vector is generated by applying the voltage limiting constraint described in equation (18), where “Ld_nom” and “Lq_nom” are the nominal d-axis and q-axis stator inductance value, Ψ r is magnetic rotor flux amplitude. The Input signal is the q-axis stator current reference (denoted as ISQ_REF) signal. The output signal is the stator d-axis current reference (denoted as ISD_REF). [0000] ISD_REF = min  ( 0 , - ψ r L d_nom + ( mod   u_max * U dc 3 * ω em * L d_nom ) 2 - ( L q_nom L d_nom * ISQ_REF ) 2 ) ( 18 ) [0082] FIG. 3 shows a simple and effective method for sinusoidal response amplitude measurement for the d-axis or q-axis stator flux/current signals. The injected sinusoidal disturbance signal has a frequency defined as f_Disturb, the angular frequency of injected signal is represented as ω o =2πf_Disturb. The d-axis or q-axis flux/current signal is fed into a resonant filter to remove the DC component and the frequency component other than the injected disturbance signal frequency. The resonant filter output signal is then phase shifted 90° using a phase shift filter. The sinusoidal response amplitude of the signal is computed from the orthogonal signals before and after 90° phase shift. [0083] The transfer function of the resonant filter is given by equation (19), where “x1” is resonant filter input signal, “y1” is resonant filter output signal, and “K” is the resonant band width adjustment coefficient. The transfer function of the 90° phase shift filter is given in equation (20), where “y1” is phase shift filter input signal and “y2” is phase shift filter output signal. The sine response amplitude of signal “x1” (denoted as “X1_AC_AMP”) is computed from equation (21). [0000] y   1 x   1 = K * ω 0 * s s 2 + K * ω 0 * s + ( ω 0 ) 2 ( 19 ) y   2 y   1 = s - ω 0 s + ω 0 ( 20 ) x   1  _AC  _AMP = ( y   2 ) 2 + ( y   1 ) 2 ( 21 ) [0084] FIGS. 4A and 4B (which are logically connected through connections E 1 and E 2 ) illustrate the general implementation procedure for stator inductance profile identification which is applicable for both stator flux vector control system and stator current vector control system. [0085] To simplify the implementation, the self-saturation “Lq” profile and cross-saturation “Ld” profile can be identified separately from the self-saturation “Ld” and cross-saturation “Lq” profile in two sequential stages as described below: [0086] The first stage is the process of the self-saturation induced “Lq” profile and cross saturation induced “Ld_CC” profile identification. In this stage, the q-axis stator flux/current reference level is adjusted so that the q-axis current is ramped to the desired testing q-axis current level (denoted as “ISQ_Test”). The d-axis flux/current reference is computed from the voltage limit constraint with minimum d-axis current applied sufficient to keep the PWM modulator working in linear modulation range when speed is high in identification process. When the desired q-axis test current level is reached, a sinusoidal disturbance signal of small amplitude is injected into the both d-axis and q-axis stator/flux current reference. A certain time delay is applied to wait for the system transition dynamic disappeared. Afterwards, the computed “Lq” is stored into the self-saturation “Lq” profile table and computed “Ld” is stored into the cross-saturation “Ld_CC” profile table. When inductance measurement on one ISQ_Test” level is obtained, the sinusoidal single disturbance injection is removed. Then, after the signal transition disappeared, the q-axis stator current (low pass filtering can be applied to removed measurement noise) is stored into ISQ table corresponding to the “Lq” and “Ld_CC” profile table. The stator flux/current references are ramped up/down to the next “ISQ_Test” current level and the process repeats till the inductance profile measurement at all ISQ test current level has been completed. Afterwards, the stator flux/current references are ramped down to zero and the first stage for stator inductance profile identification is thus completed. [0087] The second stage is the process of the self-saturation “Ld” profile and cross-saturation “Lq_CC” profile identification. In the second stage, the identification is performed in a similar way as the first stage identification process. The only difference is that q-axis stator flux/current reference is closer to zero during d-axis testing current (denoted as “ISD_Test”) ramp up/down process. [0088] The above stator inductance identification process is illustrated using the measurement data obtained in an IPM machine in the generator start-up process for a stator flux control system in FIG. 5 , FIG. 6 , and FIG. 7 . [0089] FIG. 5 shows the measured stator flux and stator current signals for the IPM machine from stage (1) to stage (2) of stator inductance identification process. The orthogonal sinusoidal signals for the corresponding stator current or stator flux signals after the resonant filter and the 90° phase shift filter are also given in FIG. 5 . [0090] FIG. 6 shows the zoom-in plot of FIG. 5 in inductance identification stage (1) at stator current level ISQ around 2800A and ISD around 100A. The self-saturation induced “Lq” inductance value and cross-saturation induced “Ld” inductance value at ISQ=2800A are thus identified and stored in to the corresponding “Lq” profile table and “Ld_CC” profile table. [0091] FIG. 7 shows the zoom-in plot of FIG. 5 in inductance identification stage (2) at stator current level ISQ around 500A and stator current ISD around 1700A. The self-saturation induced “Ld” inductance value and cross-saturation induced “Lq” inductance value at ISD=1700A are thus identified and stored in to the corresponding “Ld” profile table and “Lq_CC” profile table. NOMENCLATURE [0092] θ m rotor mechanical position θ em rotor electrical position estimated from encoder position measurement θ em rotor electrical angular speed estimated from encoder position measurement ψ r magnetic rotor flux amplitude Udc DC link voltage Rs stator resistance L d actual d-axis stator inductance L q actual q-axis stator inductance Ld_NOM nominal d-axis stator inductance Lq_NOM nominal q-axis stator inductance i* FP or IS_FP_REF field power stator current reference i* MAG or IS_MAG_REF magnetization current reference i* FP — AC or IS_FP_AC_REF field power stator current sinusoidal test reference signal i* mag — AC or IS_MAG_AC_REF magnetization current sinusoidal test reference signal i* FP — DC or IS_FP_DC_REF field power stator current reference signal magnitude level used in test i* mag — DC or IS_MAG_DC_magnetization current reference signal magnitude level used in test ψ* FP — 1 or FLUX_FP_REF — 1 field power stator flux reference before voltage limiting constraint applied ψ* MAG — 1 or FLUX_MAG_REF — 1 magnetization flux reference before voltage limiting constraint applied ψ* FP or FLUX_FP_REF field power stator flux reference after voltage limiting constraint applied ψ* MAG or FLUX_MAG_REF magnetization flux reference after voltage limiting constraint applied i* sd — AC (or ISD_AC_REF) sinusoidal D-axis stator current reference signal i* sq — AC (or ISD_AC_REF) sinusoidal Q-axis stator current reference signal i* sd — DC (or ISD_DC_REF) D-axis stator current reference amplitude level used in test i* sq — DC (or ISD_DC_REF) Q-axis stator current reference amplitude level used in test i* sd — 1 (or ISD_REF — 1) D-axis stator current reference signal before voltage limiting constraint applied i* sq — 1 (or ISQ_REF — 1) Q-axis stator current reference signal before voltage limiting constraint applied i* sd (or ISD_REF_) D-axis stator current reference signal after voltage limiting constraint applied i* sq (or ISQ_REF_) Q-axis stator current reference signal after voltage limiting constraint applied U* sα stator voltage reference α component U* sβ stator voltage reference β component U* sd stator voltage reference D-axis component U* sq stator voltage reference Q-axis component U sα stator voltage α component U sβ stator voltage β component i abc measured stator three phase current i sα measured stator current α component i sβ measured stator current β component i sd (or ISD) measured stator current D-axis component i sq (or ISQ) measured stator current Q-axis component ψ sα observed stator flux α component ψ sβ observed stator flux β component ψ sd observed stator flux D-axis component ψ sq observed stator flux Q-axis component FLUX_D_AC_AMP sinusoidal response amplitude of D-axis stator flux FLUX_Q_AC_AMP sinusoidal response amplitude of Q-axis stator flux ISD_AC_AMP sinusoidal response amplitude of D-axis stator current ISQ_AC_AMP sinusoidal response amplitude of Q-axis stator current
Parameters of PM machines, especially for IPM machine, are known to vary by significant amounts. This affects the controllability of such machines, which may lead to reduced power loading capability and increased losses. The present invention relates to a method for PM machine inductance profile identification based on voltage mode stator flux observation which could be easily integrated to the generator start-up process in wind turbine application for both stator flux vector feedback control system and current vector feedback control system.
7
This application is a National Stage completion of PCT/EP2007/059162 filed Sep. 3, 2007, which claims priority from German application serial no. 10 2006 044 109.5 filed Sep. 20, 2006. FIELD OF THE INVENTION The invention concerns a connection of a first to a second cylindrical component and a method for assembling the two components. BACKGROUND OF THE INVENTION Cylindrical components, especially hollow cylinders, stepped cylinders or pot-shaped cylinders, are used for example in automatic transmissions for motor vehicles. Such cylinders accommodate planetary gearsets and/or shift elements in the form of clutches or brakes, and can also comprise internal or external teeth for connection to other components such as inner or outer disks. A component of this type is disclosed in the older, not previously published utility-model application DE 20 2006011424.6 by the present applicant as a cylinder, for example configured as an inner disk carrier. In that case the cylinder encloses a planetary gearset on the input side and two shift elements. Such a cylinder is produced as a deep-drawn component made from a deep-drawing steel, so that the length of the cylinder is limited by production technology considerations. In modern transmission developments cylindrical components are needed, whose axial length is larger than can be produced by conventional deep drawing methods. In such cases components of that type can be made by pressure rolling, a process known for example from DE 43 13 648 C2 or EP 0 955 110 B1. However, cylindrical components produced by pressure rolling are more expensive to manufacture. SUMMARY OF THE INVENTION The purpose of the present invention is to provide a cylindrical component of the required length, which can be produced inexpensively. According to the invention a plug-in connection is provided between two cylindrical components which, together, form a component of longer axial length. The first component has locking elements arranged at its front end and the second component has corresponding windows into which the front-end locking elements can be plugged by axial movement. This produces a compact joint between two cylindrical components, which can transfer both circumferential forces and axial forces (in the compression direction). The two components form an overlap zone of larger wall thickness corresponding to the sum of the wall thicknesses of the two individual components. Compared with known connections, for example by interlocking teeth, the connection according to the invention is very small in the radial direction, i.e. it has advantages in relation to the radial space occupied. The front-end locking elements are preferably formed as tabs which stand out relative to the cylinder body and so form end or crown teeth. The corresponding windows with which the crown teeth are brought into engagement are positioned in the second component in a transition zone from a larger to a smaller inside diameter. This enables the front-end teeth to be pushed in the axial direction into the windows until the front edges of the crown teeth encounter the windows. During this insertion process the two components are pushed toward one another through the overlap zone in a telescopic manner. According to a preferred embodiment, in the overlap zone on the second component, i.e. the outer component, bracing tabs are cut free and on the first component, i.e. the component arranged on the inside, windows are cut out, in which the supporting tabs engage with interlock and thus transfer axial forces in the opposite direction (the tension direction). In this way the connection according to the invention can transfer axial forces in both directions, i.e. on the one hand by means of the end surfaces of the end teeth and on the other hand by means of the end surfaces of the bracing tabs. According to a preferred embodiment the bracing tabs have an initial shape which allows the inner component to be pushed into the outer component. By pressing from outside, for example by means of a device, the initial shape is brought to a final shape which is made possible by a type of snap effect, i.e. from a convex to a slightly concave shape. Alternatively, the bracing tabs can be made as springy tongues which, when the inner component is inserted, are first pushed outward and in the end position of the two components clip back into the windows in the manner of a catch connection. This variant allows assembly without any device that grips from the outside. The number of bracing tabs and front-end locking elements (crown teeth) is different: since the crown teeth also transfer circumferential forces while in contrast the bracing tabs do not, in a preferred embodiment about thirty crown teeth are provided, whereas for the bracing tabs only a smaller number are needed, which is matched to the axial forces to be transferred. In an advantageous embodiment the two components can be made from different materials, these respective materials being chosen in accordance with the different demands on the first and second component. In a preferred embodiment both components can be made as deep-drawn components. This has advantages in relation to production costs, especially compared with pressure rolling. The connection according to the invention can be used particularly advantageously in motor vehicle automatic transmissions, i.e. for a cylinder composed of two part-cylinders in an automatic transmission for accommodating planetary gearsets and/or shift elements. In this application it is advantageous to make the first component, i.e. the first part-cylinder from a non-magnetizable material, for example aluminium, an aluminium alloy or an austenitic steel. This brings the advantage that a speed sensor that works by the well-known Hall effect can be arranged in the area of the first component, which is not possible with ordinary deep-drawing steels that can be magnetized. Thus, the sensor can detect the rotation speed of a transmission component such as a carrier shaft of a planetary gearset. According to the method, the two components are orientated end-to-end and pushed one into the other until the front faces of the crown teeth encounter the windows of the other component. Then, locking takes place by the bracing tabs in the other, opposite axial direction. Here, two variants are possible: the first provides that the bracing tabs are pressed into the windows of the other component by means of a device which grips from the outside, and during this the bracing tabs snap from a convex initial shape to a concave final shape, thereby axially bracing the two components together. In a second, preferred variant the axial locking takes place automatically, i.e. the bracing tabs made as elastic tongues spring inward when the inner component has been inserted, and clip into the windows. No other device is needed for this. BRIEF DESCRIPTION OF THE DRAWINGS An example embodiment of the invention is illustrated in the drawing and will be described in greater detail below. The figures show: FIG. 1 : A cylinder, consisting of a first and a second part-cylinder, for an automatic transmission FIG. 2 a : Partial section through the first part-cylinder FIG. 2 b : Partial view of the first part-cylinder in the direction A FIG. 3 a : Partial section through the second part-cylinder FIG. 3 b : View of the second part-cylinder in the direction B FIG. 4 a : Connection of the two part-cylinders according to the invention, showing the detail X in FIG. 1 FIG. 4 b : Another view of the detail X. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an axial section through a cylinder 1 that can be used in an automatic transmission of a motor vehicle to accommodate a planetary gearset and shift elements (none of them shown). The cylinder 1 is composed of two part-cylinders, a first part-cylinder 2 and a second part-cylinder 3 , which are connected firmly to one another by a plug-in joint 4 . In the outer, end area of the part-cylinder 2 is arranged a guide disk 5 , which is connected to the first part-cylinder 2 by means of locking teeth 5 a , 2 a . The guide disk 5 is part of the planetary gearset (not shown). At the opposite end of the cylinder 1 a ring gear 6 is connected fixed to the part-cylinder 3 , i.e. by means of a weld seam 7 , although locking teeth would also be possible in place of the weld seam 7 . In the area of the first part-cylinder 2 is arranged a speed sensor 8 which consists of a static sensor component 8 a positioned outside the part-cylinder 2 and a rotating magnetic ring 8 b arranged inside the first part-cylinder 2 . The first part-cylinder 2 , which is therefore between the sensor component 8 a and the rotating magnetic ring 8 b , is made from a non-magnetic material, preferably aluminium, an aluminium alloy or an austenitic steel such as V4A. Thus the speed sensor 8 , which works according to the well-known Hall effect, is functional. The second part-cylinder 3 is made from an ordinary commercial deep-drawing steel and can therefore be welded to the ring gear 6 . Preferably, both part-cylinders 2 , 3 are deep-drawn components, i.e. made by deep drawing from a sheet blank. FIGS. 2 a and 2 b show, respectively, the first part-cylinder 2 in section and seen from above (in the direction A). At the front, i.e. in the area of the joint 4 ( FIG. 1 ) the first part-cylinder 2 has end- or crown-teeth 9 , consisting of tabs or teeth 9 a chamfered at the end, with gaps 9 b arranged between them. Furthermore, on the circumference of the part-cylinder 2 are arranged rectangular or square openings in the form of windows 10 , whose purpose will be explained below. FIGS. 3 a and 3 b show the part-cylinder 3 in section and seen from above (in the direction B). The second part-cylinder 3 has a front edge 3 a and, in its end area, an inside diameter D 1 which corresponds to the outside diameter of the first part-cylinder 2 , and a reduced inside diameter D 2 which corresponds to the inside diameter D 2 of the first part-cylinder 2 . The transition from the larger inside diameter D 1 to the smaller inside diameter D 2 is shown as a beveled section 11 . In the area of the beveled section 11 , distributed around the circumference, rectangular openings in the form of windows 12 are cut out of the cylinder surface of the second part-cylinder 3 , the width of these windows (in the circumferential direction) corresponding to the width of the teeth 9 a of the end tooth array 9 of the first part-cylinder 2 . In addition, in the cylinder surface of the second part-cylinder 3 tongues 13 , so-termed bracing tabs, are cut free, i.e. they are surrounded by an approximately U-shaped gap 14 . As can be seen in FIG. 3 a the bracing tabs, seen in cross-section, are convexly curved and project outward a little above the gap opening 14 . The form of the bracing tabs 13 illustrated is a so-termed initial shape, i.e. a shape before the two part-cylinders 2 , 3 are assembled together. This enables the first part-cylinder 2 to be pushed in the axial direction into the second part-cylinder 3 , so that the slightly chamfered teeth 9 a can engaged with the windows 12 . The windows 12 have abutment surfaces 12 a against which the ends 9 c of the teeth 9 come into contact. FIGS. 4 a and 4 b show the detail X from FIG. 1 , i.e. the connection 4 of the two part-cylinders 2 , 3 , on an enlarged scale. The same parts are given the same indexes. The front-end areas of the part-cylinders 2 , 3 pushed into one another form an overlap zone ü which extends from the front surfaces 9 c of the end teeth 9 as far as the front edge 3 a of the second part-cylinder 3 . The initial shape of the bracing tab 13 is here shown by broken lines. The bracing tab 13 is pressed inward by a device (not shown) to position 13 ′ (continuous line) so that its front surface 13 a presses against the corresponding contact surface 10 a of the window 10 , whereby the two part-cylinders 2 , 3 are axially braced. This joint by the bracing tabs 13 ′ of the second part-cylinder 3 can transfer axial tensile forces between the two part-cylinders 2 , 3 . Compression forces in the axial direction are transferred by the end teeth 9 . Circumferential forces between the two part-cylinders 2 , 3 are also transferred by the end teeth 9 , but via the lateral surfaces of the teeth 9 a which, in FIG. 4 a , are shown as a cross-hatched area F. As a variation from the example embodiment illustrated, the bracing tabs 13 can also be made as elastically springy tongues which, when the first part-cylinder is inserted into the second part-cylinder, are first pushed outward by the end surface of the first part-cylinder and—when the end faces 9 c have come up against the abutment surfaces 12 a —spring back into the windows 10 . Indexes 1 Cylinder 2 First part-cylinder 2 a Locking teeth 3 Second part-cylinder 3 a Front edge 4 Connection (between the first and second part-cylinders) 5 Guide disk 5 a Locking teeth 6 Ring gear 7 Weld seam 8 Speed sensor 8 a Sensor component 8 b Magnetic ring 9 End teeth 9 a Tooth 9 b Gap 9 c End surface 10 Window 11 Beveled section 12 Window 12 a Abutment surface 13 Bracing tab 13 ′ Bracing tab (final shape) 14 Gap D 1 Outside diameter (first part-cylinder) D 2 Inside diameter (first part-cylinder) F Force transfer area ü Overlap zone
A connection ( 4 ) of a first ( 2 ) to a second ( 3 ) cylindrical component for the transfer of circumferential and axial forces. The first component ( 2 ) has locking elements ( 9 a ) arranged on its circumference and at the end, the second component ( 3 ) has windows ( 12 ) associated with the locking elements ( 9 a ), and the first and second components ( 2, 3 ) can be plugged one into the other at the ends to form a positive interlock between the locking elements ( 9 a ) and the windows ( 12 ).
8
BACKGROUND OF THE INVENTION The present invention relates to a rectifier arrangement, and, more particularly, to a rectifier arrangement for a three-phase generator for a motor vehicle. Rectifier arrangements for three-phase generators are known. If the three-phase generators are used, for example, to supply the electrical system in motor vehicles, the three-phase alternating current generated in the three-phase generators must be rectified because of the battery charging required in the motor vehicle. For this purpose, semiconductor power diodes are provided which are interconnected in a three-phase bridge connection. In this case, each half wave of each phase is assigned one diode, with the result that for full-wave rectification the three-phase bridge connection is formed from a total of six power diodes (see DE 40 18 710 A1, corresponding to U.S. Pat. No. 5,296,770). In this case, three positive diodes are connected for the positive side and three negative diodes for the negative side. It is known for the power diodes to be constructed as press-fit diodes, power diodes of like polarity respectively being pressed into one heat sink. The heat sinks are in this case sandwiched together, having an interposed insulating part which receives the electrical connections between the power diodes and the three-phase winding. A press-fit base of the press-fit diodes simultaneously undertakes in this case permanent thermal and electrical connection of the power diodes to the heat sink. However, it is possible to produce such a three-phase bridge connection comprising press-fit diodes only with a very high outlay. Furthermore, it is necessary there to have crimp connections welded or soldered to the terminals, in order to absorb thermal and mechanical stresses at the soldering or welding points. SUMMARY OF THE INVENTION According to the invention, the rectifier arrangement, especially for the three phase generator of a motor vehicle, includes at least one power diode of positive polarity and at least one power diode of negative polarity assigned to respective half-waves of each of three phases (U, V, W) of a three-phase current; a cooling arrangement for the power diodes including heat sinks, the power diodes of like polarity being arranged on respective heat sinks in an electrically and thermally conductive manner; at least one electrically insulating part assembled with the heat sinks and accommodating electrical connections between the at least one power diodes of positive and negative polarities and the three phases (U, V, W), and an electrically conductive connection of the at least one positive power diode and the at least one negative power diode of each of the three phases (U, V, W) which extends in the at least one electrically insulating part to one of the three phases (U, V, W) and includes spring elements making electrical contact with respective power diodes of positive and negative polarity outside the insulating part. The rectifier arrangement according to the invention renders it possible, by contrast, to produce the rectifier arrangement simply and cost effectively and largely to minimize fatigue phenomena of the thermally and electrically conductive terminal connections of the rectifier arrangement during operation. Because the power diodes are constructed as diode chips which are connected in a planar fashion to the heat sink, and that an electrically conductive connection is produced between the power diodes and the phases of the three-phase current via a spring element in each case, there is on the one hand a simple design of the overall rectifier arrangement, which can be produced with a reduced manufacturing outlay and thus in a cost effective fashion. In addition, the rectifier arrangement can be constructed very robustly, with the result that there is a high reliability against mechanical, thermal and chemical fatigue even in the event of high loading. In a preferred embodiment of the rectifier arrangement each of the spring elements is a meandering spring having a soft characteristic. Each of the phases (U, V, W) is advantageously assigned a pair of the meandering springs making electrical contact with respective positive and negative power diodes. The electrically conductive connection can be formed by a conductor track, the spring elements and the connected conductor track for each phase (U, V, W) can be each formed as part of a punched grid; and each punched grid can be sheathed, advantageously injection coated, with an insulating material except at regions of each of the punched grid including the spring elements and a terminal connection for each of the phases (U, V, W). The at least one electrically insulating part advantageously consists of the punched grid and the insulating material. In other preferred embodiments of the rectifier arrangement the at least one electrically insulating part is arranged between heat sinks so that in the region of the at least one power diodes of positive and negative polarity the at least one electrically insulating part is provided with respective cutouts forming respective cavities in which the respective meandering springs are arranged. Advantageously the at least one electrically insulating part has at least one slot connected via at least one channel in the heat sink to at least one of the cavities. A sealing compound can be provided in the slots and the cavities to reduce thermal, mechanical and chemical fatigue of the spring elements. The sealing compound can be provided with embedded elastic regions, including air-filled balloons and/or foam to improve their effectiveness. BRIEF DESCRIPTION OF THE DRAWING The objects, features and advantages of the present invention will now be illustrated in more detail by the following detailed description, reference being made to the accompanying drawing in which: FIG. 1 is an electric circuit diagram of a rectifier arrangement as a three-phase bridge connection; FIG. 2 is a cross-sectional view through a region of a finally assembled rectifier arrangement; FIG. 3 is a top view of a rectifier arrangement in accordance with FIG. 2; FIG. 4 is a cross-sectional view of a diode chip; FIG. 5 is a top view of a diode chip; FIG. 6 is a top view of a connection plate; FIG. 7 (a) is a top view of a positive heat sink; FIG. 7 (b) is a rear view of a positive heat sink; FIG. 8 (a) is a top view of a negative heat sink; FIG. 8 (b) is a rear view of a negative heat sink; and FIG. 9 is a view of a finally assembled rectifier arrangement in a see-through representation. DESCRIPTION OF THE PREFERRED EMBODIMENTS The electrical diagram of a rectifier arrangement for a three-phase generator is shown in FIG. 1. The phases U, V, W of the stator winding of the three-phase generator (not represented) are connected to a three-phase bridge connection 10, each phase being connected to a positive diode 12 and a negative diode 14. The anodes of the negative diodes 14 are connected to a supply terminal 16 and the cathodes of the positive diodes 12 are connected to a supply terminal 18. The supply terminals 16 and 18 are connected via counters (not represented here) to electric consumers in motor vehicles and to a motor vehicle battery (likewise not represented). Furthermore, each phase U, V, W is connected to an excitation diode 20 whose interconnected cathodes lead via sliprings to an excitation winding (not represented) in the rotor of the three-phase generator. Each of the positive diodes 12 and negative diodes 14 passes a half wave of the single-phase alternating current in the phase to which they are connected. The positive diodes 12 allow the positive half waves to pass and the negative diodes 14 the negative half waves. As a result, a lightly undulating direct current is produced by the three-phase alternating current of the three-phase generator. Lost heat which must be dissipated in a suitable way is produced in this case in the diodes 12 and 14 during operation of the generator. FIG. 2 shows a sectional representation through a subregion of a finally assembled rectifier arrangement, designated here in general by 22. The aim is to explain the basic idea of the present invention with the aid of FIG. 2. A negative diode 14 and a positive diode 12 of the three-phase bridge connection 10 are shown, the particular design of which is explained in more detail with the aid of FIGS. 4 and 5. The negative diode 14 is arranged in a thermally and electrically conductive fashion on a negative heat sink 24. The positive diode 12 is arranged in a likewise thermally and electrically conductive fashion on a positive heat sink 26. For this purpose, the heat sinks 24 and 26 have, for example, platform-like projections 28 on which the diodes 12 and 14, respectively are, for example, soldered. The projections 28 can be formed, for example, by appropriate depressions 29 in the heat sinks 24 and 26, respectively. As indicated in FIG. 2, in order to enlarge the effective cooling surface the heat sinks 24 and 26 can have cooling studs 30 on their outer surfaces. A connection plate 32 is arranged between heat sinks 24 and 26, thus resulting overall in a sandwich-type design of the rectifier arrangement 22, specifically composed of the negative heat sink 24, the connection plate 32 and the positive heat sink 26. The connection plate 32 has a punched grid 34 (still to be explained), which is sheathed by an insulating material 36 in part, i.e. with the exception of connection and spring regions. The insulating material 36 prevents an electrically conductive connection between the negative heat sink 24 and the positive heat sink 26, on the one hand, and between the punched grid 34 and the heat sinks 24 and 26, respectively, on the other hand. In the region of the negative diode 14, the connection plate 32 has a continuous cutout 38, with the result that a cavity 40 is produced here. In the region of the positive diode 12, the connection plate 32 has a further continuous cutout 42, with the result that a cavity 44 is produced here. Inside the cavities 40 and 44, the punched grid 34 forms in each case a meandering spring 46 and 48, respectively. The spring 46 is preloaded in this case in such a way that it contacts the negative diode 14, and the spring 48 is preloaded in such a way that it contacts the positive diode 12. The contact between the spring 46 or 48, respectively, and the diodes 14 and 12, respectively, can take place either exclusively by a spring force in accordance with the preloading of the springs 46 and 48, or the latter are additionally soldered or welded, for example, to the diodes 14 and 12, respectively. In addition to the springs 46 and 48, the punched grid 34 further forms conductor tracks 50 (FIG. 3) which are provided with a supply terminal 52 to which one of the phases U, V or W of the three-phase generator can be connected. The segment shown in FIG. 2 of the rectifier arrangement thus forms the arrangement for rectifying one of the phases of the three-phase alternating current of the three-phase generator. The entire rectifier arrangement 22 therefore has a total of three of the regions shown in FIG. 2 which are constructed in a fully analogous fashion. It becomes clear with the aid of FIG. 3 that the punched grid 34 for one phase respectively comprises the springs 46 and 48, at least one conductor track 50, a supply terminal 52 and the regions 54 connecting the springs 46 and 48 to one another. The punched grid 34 can, for example, be punched out of a plate-shaped material available in an appropriate size, with the result that the above-mentioned individual structures are produced. After punching has been performed, the springs 46 and 48, respectively, are correspondingly plastically deformed, thus producing preloading of the springs 46 and 48, respectively, in the direction of the negative diode 14 or the positive diode 12, respectively. The springs 46 and 48 respectively, have a characteristic which is as soft as possible, with the result that after the assembly of the connection plate 32 a continuous pressure is exerted on the diodes 14 and 12, respectively. The punched grids required for each phase U, V, W are sheathed with the insulating material 36 before assembly, thus producing the connection plate 32. Thus, overall the connection plate 32 has the punched grids 34 of the respective phases U, V and W. The punched grids 34 consist, for example, of pure copper or higher grade bronzes. In the region bordering the cavities 40 and 44, respectively, the connection plate 32 has at least one slot 56 which is respectively connected to the cavities 40 and 44 via at least one channel 58 in the heat sink 24 or 26. The regions 60 of the connection plate 32, which are respectively between the cavity 40 and one slot 56 and the cavity 44 and another slot 56 have a somewhat greater height than the entire connection plate 32. In this case, the regions 60 at least partially engage in local depressions 62 in the channels 58, around the projections 28, in the heat sinks 24 and 26, respectively. In the region of the cavity 44, the negative heat sink 24 has an assembly opening 64 which can be sealed by a cover 66. The procedure for assembling the rectifier arrangement 22 is as follows. The individual parts of the rectifier arrangement 22 are prepared separately. Thus, the negative heat sinks 24 and positive heat sinks 26 can be shaped as desired for example by pressure die-casting and, optionally, by subsequent machining. The negative heat sink 24 can in this case advantageously be simultaneously structured as a slipring end shield for the three-phase generator, with the result that it is possible to dispense with the additional arrangement of a negative heat sink. Furthermore, the punched grids 34 are punched out in accordance with the desired contour and injection coated to the connection plate 32. After production of the connection plate 32, the springs 46 and 48 are shaped in an appropriately plastic fashion in the region of the cutouts 40, 44. In a first assembly step, the negative diodes 14, constructed as diode chips, are fastened to the negative heat sink 24, for example by being soldered onto the above-mentioned projections 28. The positive diodes 12, likewise constructed as diode chips, are fastened in a similar way to the positive heat sink 26. The preproduced connection plate 32 is now fastened, for example riveted, to the negative heat sink 24 in a positionally oriented fashion. The positional orientation of the connection plate 32 is performed such that the regions 60 of the connection plate 32 engage at least partially in the depressions 62 of the negative heat sink 24. Because of the assembly of the connection plate 32, the spring 46 presses by virtue of its preloading against the negative diode 14, with the result that a sufficiently large contact pressure is produced in accordance with the selected preloading. The spring 46 can additionally be soldered or welded to the negative diodes 14. This can be performed, for example, by means of a laser. In the next step, the positive heat sink 26 is fastened, for example screwed, in a positionally oriented fashion to the assembly composed of the negative heat sink 24 and the connection plate 32. As a result, the positive diodes 12 come to be situated in the cavity 44 and press against the preloaded spring 48, thus producing a sufficiently high contact pressure between the positive diodes 12 and the springs 48. The springs 48 can likewise additionally be soldered to the positive diodes 12. This purpose is served by the assembly opening 64 in the negative heat sink 24, through which the spring 48 can make appropriate contact with the positive diode 12. After contact has been made, the assembly opening 64 is sealed in an airtight fashion by the cover 66. A continuous contact pressure is maintained on the diodes 14 and 12, respectively, during operation of the rectifier arrangement 22 by the preloading of the springs 46 and 48. In the next step, the remaining cavities 40 and 44 are sealed or packed with foam material. A sealing compound is, for example, pressed under pressure into the previously evacuated cavities and thereby reliably fills up the latter. As an alternative to this, the sealing compound or foam packing compound can also be filled into the cavities 40 and 44 before the cover 66 is placed on. The effect of this vacuum pressure die-casting is to avoid vibration of the springs 46 and 48, on the one hand, as well as to avoid the ingress of moisture to the diodes 14 and 12, respectively, or to their contact regions. The sealing compound likewise reaches the slots 56 via the channels 58. The result is to achieve a reliable force-closed joint between the heat sinks 24 and 26, respectively, and the connection plate 32. Because the regions 60 of the connection plate 32 engage in the depressions 62 of the heat sinks 24 and 26, respectively, it is guaranteed in the event of a particularly high loading of the rectifier arrangement 22, such as can occur, for example, during operation of a motor vehicle, and that the rectifier arrangement 22 is arranged directly on a three-phase generator of the motor vehicle, that the sealing compound is essentially subjected only to a shear stress, i.e. as seen at right angles to the connection plate 32. A peeling stress occurring horizontally relative to each connection plate 32 is thus largely avoided. Reliability of contact is thereby provided between the diodes 14 and 12, respectively, and the springs 46 and 48, respectively. For the purpose of further increasing the reliability of contact of the diodes 14 and 12, respectively, elastic regions, for example air-filled balloons, can be cast in the sealing compound. This renders it possible, first and foremost, to compensate for a thermal expansion response of the sealing compound because of the changing temperatures which occur during operation. If a soft sealing compound is used as the sealing compound, the former can be kept permanently under hydrostatic compressive stress such that a sufficiently strong adhesion of the sealing compound and the seal of the cavities is provided at any time even when relative changes in the positions of the heat sinks 24 and 26 and the connection plate 32 relative to one another occur during operation of the rectifier arrangement 22. FIG. 3 represents in a plan view the region of the rectifier arrangement 22 which is shown in FIG. 2, the negative heat sink 24 and the negative diode 14 as well as the slots 56 not being shown. It becomes clear, in particular, that the punched grid, which is represented here in a partially dashed fashion and cast into the connection plate 32, consists of the meandering springs 46 and 48, the conductor track 50, the supply terminal 52 and the connecting regions 54, which likewise serve as conductor track. Because of the meandering course of the springs 46 and 48, the latter having as soft a characteristic as possible, it is possible to achieve preloading of the springs 46 and 48 which is sufficient for the contact pressure inside the space available in the cavities 42 and 44, respectively. It is thus possible at the same time to preload the springs 46 and 48 in opposite directions in a region in which they are situated relatively close to one another. The design of the diodes 12 and 14 is illustrated in FIGS. 4 and 5. The negative diode 14 is designed in principle in the same way as the positive diode 12. Only the pn junction of the diodes 12 and 14, respectively, is arranged in an appropriately laterally inverted fashion. The diodes consist of a base 68 to which a diode chip 72 is applied via a solder 70. A head plate 76 is applied to the diode chip 72 via a further solder 74. Both the base 68 and the head plate 76 consist of an electrically conductive material. The base 68 serves to fasten the diode chip 72 to the heat sinks 24 and 26, respectively. The base 68 is soldered for this purpose to the heat sinks, for example. The diode chip 72 makes contact with the springs 46 and 48, respectively, via the head plate 76. The diode chip 72 is thus simultaneously protected against excess mechanical stress due to loading of the springs 46 and 48, respectively. FIG. 6 shows a plan view of a complete connection plate 32. It is clear that the connection plate 32 extends in an annular fashion and is thus adapted to the contour of a three-phase generator. The connection plate 32 has a total of three punched grids 34, respectively for the phases U, V and W of the three-phase generator. A further punched grid 34a can be used, for example, to rectify the current flowing via the star point Y of the phases U, V, W. The connection plate 32 thus consists overall of an insulating material 36 in which the punched grids 34 are embedded. The connection plate 32 has the above-mentioned cutouts 38 and 42, respectively, where the springs 46 and 48 are constructed. Furthermore, additional cutouts (not shown in the drawing) are provided in the connection plate 32 which are provided on the one hand for fastening means and on the other hand for tapping D+/V (controller terminal), B+ (generator terminal 18 to the consumer or to the battery), W (terminal for speed) or D (generator terminal 16) signals of the three-phase generator. The correspondingly desired connections can be provided by appropriate punchings of the punched grids 34 by appropriately different punching of the punched grids 34. The spring elements 46a and 48a, indicated here, for the additional diodes connected to the star point Y can subsequently be punched away in applications where they are not required. However, there is no intention to provide further details of the connection plate 32 in this description. The positive heat sink 26 is shown in a plan view in FIG. 7a and in a rear view in FIG. 7b. The positive heat sink 26 has the same shape as the connection plate 32, i.e. the heat sink likewise extends in an annular fashion in accordance with the contour of a three-phase generator. The depressions 29 in the positive heat sink 26 which lead to the formation of the platform-like projection 28 become clear in the plan view. The cooling studs 30, which are arranged over the entire positive heat sink 26 and lead to an enlargement of the cooling surface of the positive heat sink 26 are seen in the rear view of FIG. 7b. The positive heat sink 26 forms additional cutouts (not to be considered here in more detail) for connecting elements or bushings of terminals of the three-phase generator. The negative heat sink 24 is represented in a plan view in FIG. 8a and in a rear view in FIG. 8b. The negative heat sink 24 can serve simultaneously as a slipring end shield of a three-phase generator, and has a circular shape adapted to the shape of the three-phase generator. The depressions 29 and 62 which lead to the formation of the projection 28 are shown in the rear view. Indicated here in the depression 29 is the opening 64 which permits access for assembly to the cavity 44 of the connection plate 32. There is no intention to provide further details of the negative heat sink 24 or the slipring end shield in this description. Finally, FIG. 9 shows an entire rectifier arrangement 22 in a plan view, the aim being to illustrate the sandwich-type design of the rectifier arrangement 22 by means of a see-through representation. Identical parts are provided, as in the preceding figures, with identical reference symbols and are not explained again here in connection with FIG. 9. A designation is performed here only with reference to the phase U, the design at the other phases W and V and at the star point Y of the rectifier arrangement 22 being identical. It becomes clear from the enlarged representation shown here that it is possible to embed additional conductor tracks 78 in the connection plate 32, which are suitable, for example, for separately tapping the phase W or the phase V, or the signals B+ and D+. The conductor tracks 78 are also taken into account in this case in the corresponding punched grids 34, with the result that the required electrical conducting paths are provided. Because of the structure of the rectifier arrangement 22 according to the invention, specifically to its sandwich-like design, composed of the negative heat sink 24, the connection plate 32 and the positive heat sink 26, the arrangement can be designed simply and very robustly, with the result that the rectifier arrangement 22 can be operated reliably and economically over its entire expected lifetime or over the lifetime of the three-phase generator. Because of the meandering design of the springs 46 and 48, on the one hand compensation of any possible manufacturing tolerances during the production of the heat sinks 24 and 26, respectively, and of the connection plate 32 is guaranteed. Moreover, mechanical, thermal and chemical fatigue of the rectifier arrangement 22 can be counteracted by the springs 46 and 48, respectively, embedded in a sealing compound. While the invention has been illustrated and described as embodied in a rectifier arrangement, especially for a three-phase generator for a motor vehicle, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention. Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention. What is claimed is new and desired to be protected by Letters Patent is set forth in the appended claims.
The rectifier arrangement, preferably for a three-phase generator for a motor vehicle, has at least one power diode of positive polarity and at least one power diode of negative polarity assigned to respective half waves of each phase of the three-phase current and a cooling arrangement for the power diodes, the power diodes of like polarity being arranged on respective heat sinks in an electrically and thermally conductive fashion, and the heat sinks being sandwiched together with at least one electrically insulating part (32) which contains the electrical conductors between the diodes and the three-phase winding. The electrically conductive connections of the power diodes (12, 14) of positive and negative polarity to the phases (U, V, W) of the three-phase generator extend within the electrically insulating part (32) so that electrical contact is made with the power diodes (12, 14) of positive and negative polarities in respective cavities (40, 44) in the insulating part (32) via in each case one spring element. A punched grid (34) for each of the phases (U, V, W) extends in the cavities and includes conductor tracks (50) and spring elements (48, 49) for making electrical contact between pairs of power diodes of opposite polarity and each phase.
7
BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The disclosed embodiments of the present invention relate to an image system, and more particularly, to a de-noising method and a related image system. [0003] 2. Description of the Prior Art [0004] In the real-time digital image process, there are mainly two kinds of de-noising methods. The first kind of de-noising method is performed in a spatial domain, such as Gaussian filtering, median filtering, bilateral filtering, and non-local means (NLM) filtering with good effect. However, these spatial domain de-noising method needs a huge calculation amount to obtain a better effect, and there are side effects of image blur and details loss inevitably. [0005] The second kind of de-noising method is performed in a time domain, which considers a previous frame and a current frame at the same time with an appropriate weighted average in order to achieve the de-noising effect. Compared to the first kind of de-noising method, the top advantage is that it almost does not cause image blur or the detail loss, but the time domain de-noising method may easily increase the ghosting, or make the image not natural. Minimizing the side effects often requires very complex operation. [0006] In order to improve problems of the de-noising methods of time domain and space domain, it is also practical to merge the two kinds of methods, but a de-noising method using the time domain and the space domain at the same time will have three major problems: the first problem is a serious ghosting effect; the second problem is low image resolution; and the third problem is that when the noise is bigger, especially when the image capturing device is in a low light environment, or the image is affected by the lens shading around, the de-noising effect will be reduced. [0007] Thus, a de-noising method with low complexity and high efficiency is required in this field to improve the above problems. SUMMARY OF THE INVENTION [0008] It is therefore one of the objectives of the present invention to provide a de-noising method and a related image system, so as to solve the above-mentioned problem. [0009] In accordance with a first embodiment of the present invention, an exemplary de-noising method is disclosed. The de-noising method comprises: receiving a pixel of a current frame; deriving a de-noising coefficient according to a specific information corresponding to the pixel; and generating an output pixel by allocating a weight of the pixel and a weight of at least one pixel of a previous frame according to the de-noising coefficient, wherein the at least one pixel of the previous frame includes a co-located pixel. [0010] In accordance with a second embodiment of the present invention, an exemplary image system is disclosed. The image system comprises: a lens module, an image and signal processor, and a de-noising unit. The lens module is utilized for capturing an image information. The image and signal processor is coupled to the lens module, and utilized for converting the image information to a frame. The de-noising unit is coupled to the image and signal processor, and utilized for: receiving a pixel of the frame; deriving a de-noising coefficient according to a specific information corresponding to the pixel; and generating an output pixel by allocating a weight of the pixel and a weight of at least one pixel of a previous frame according to the de-noising coefficient, wherein the at least one pixel of the previous frame includes a co-located pixel. [0011] In accordance with a second embodiment of the present invention, an exemplary image system is disclosed. The image system comprises: a lens module, an image and signal processor, a brightness adjusting unit, and a de-noising unit. The lens module is utilized for capturing an image information. The image and signal processor is coupled to the lens module, and utilized for converting the image information to a frame. The brightness adjusting unit is coupled between the image and signal processor and the lens module, and utilized for generating an exposure control signal to the lens module according to an automatic exposure information and generating a frame rate information to a de-noising unit. The de-noising unit is utilized for: receiving a pixel of the frame; deriving a de-noising coefficient according to a specific information corresponding to the pixel; and generating an output pixel by allocating a weight of the pixel and a weight of at least one pixel of a previous frame according to the de-noising coefficient, wherein the at least one pixel of the previous frame includes a co-located pixel, and at least one pixel of the previous frame further comprises at least one pixel surround the co-located pixel. [0012] In accordance with a second embodiment of the present invention, an exemplary image system is disclosed. The image system comprises: a lens module, an image and signal processor, a brightness adjusting unit, and a de-noising unit. The lens module is utilized for capturing an image information. The image and signal processor is coupled to the lens module, and utilized for converting the image information to a frame. The brightness adjusting unit is coupled between the image and signal processor and the lens module, and utilized for generating an exposure control signal to the lens module according to an automatic exposure information and generating a frame rate information to a de-noising unit. The de-noising unit is utilized for performing a spatial domain de-noising process and a time domain de-noising process at least according to the frame rate information and a pixel of the frame, so as to generate an output pixel. [0013] Briefly summarized, the spirit of the present invention is using an adaptivity method to dynamically determine a ratio of the time domain de-noising, and further adding the spatial domain de-noising to achieve a real-time 3D de-noising method. [0014] These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings. BRIEF DESCRIPTION OF THE DRAWINGS [0015] FIG. 1 is a simplified schematic diagram illustrating a real-time adaptability 3D dynamic de-noising method according to the present invention. [0016] FIG. 2 is a diagram of a filtering function ƒ 2 in accordance with an embodiment of the present invention. [0017] FIG. 3 shows a flowchart of an exemplary real-time adaptability 3D dynamic de-noising method in accordance with a first embodiment of the present invention [0018] FIG. 4 is a relation diagram of the brightness and the Weber threshold value of the present invention. [0019] FIG. 5 is a relation diagram of the motion strength and the preposed de-noising coefficient of the present invention. [0020] FIG. 6 is a relation diagram of the distance from the center point of the frame and the adjusting coefficient in accordance with an embodiment of the present invention. [0021] FIG. 7 is a relation diagram of the distance from the center point of the frame and the adjusting coefficient in accordance with another embodiment of the present invention. [0022] FIG. 8 shows a flowchart of an exemplary real-time adaptability 3D dynamic de-noising method in accordance with a second embodiment of the present invention. [0023] FIG. 9 is a block diagram of an image system in accordance with an embodiment of the present invention. [0024] FIG. 10 shows a flowchart of an exemplary real-time adaptability 3D dynamic de-noising method in accordance with a third embodiment of the present invention. DETAILED DESCRIPTION [0025] Certain terms are used throughout the description and following claims to refer to particular components. As one skilled in the art will appreciate, manufacturers may refer to a component by different names. This document does not intend to distinguish between components that differ in name but not function. In the following description and in the claims, the terms “include” and “comprise” are used in an open-ended fashion, and thus should be interpreted to mean “include, but not limited to . . . ”. Also, the term “couple” is intended to mean either an indirect or direct electrical connection. Accordingly, if one device is coupled to another device, that connection may be through a direct electrical connection, or through an indirect electrical connection via other devices and connections. [0026] In general, in order to obtain a better de-noising effect, the characteristics of the noises have to be analyzed at first. There are two kinds of common static state image noises: salt and pepper noise and Gaussian noise. However, for the general image capturing devices, since the captured images are dynamic and the noises of each frame might be different, and the noises of each point are twinkling constantly for the vision (i.e. the whole frame is full of twinkling noises), the effect of using the spatial domain to perform the de-noising process will not be ideal in this condition, and it is more proper to use the time domain filter or use the time domain plus the spatial domain to perform the de-noising process. [0027] The spirit of the present invention is using an adaptivity method to dynamically determine a ratio of the time domain de-noising, and further adding the spatial domain de-noising to achieve a real-time 3D de-noising method. In the 3D de-noising method, the way of how to allocate the time domain de-noising strength (effect) will directly affect the user feeling. The present invention is suitable for all camera modules and shot environments. In a low light environment, for example, two different time points of captured frame are not only full of static noise, buy also contains dynamic twinkling noises. Therefore, the present invention can reduce the dynamic twinkling noise to enhance the visual perception in as far as possible under the condition of no loss of image details. In addition, the computational cost of the present invention is very low, and the present invention can be used in a variety of different ways of implementation, such as a hardware (such as a chip), a software (such as a driver, an application) or a firmware or a part or all of their combination. [0028] Please refer to FIG. 1 . FIG. 1 is a simplified schematic diagram illustrating a real-time adaptability 3D dynamic de-noising method according to the present invention. Equation (1) is the basic idea of the present invention, based on a current frame and a previous frame for a filter process. Please note that the previous frame is not limited to previous one frame. The filter process can be expressed as follows: [0000] P out =P in ×C denoising +ƒ 3 ( q )×(1− C denoising )  (1) [0029] P in is a value of a pixel in the current frame, and q is a value of another pixel in the corresponding position in the previous frame (co-located pixel), P out is a result generated by the filtering process (i.e. a new value of the pixel in the current frame). More specifically, an integrated de-noising coefficient C denoising is utilized here, and a dynamic determining method is utilized for determining an integrated de-noising coefficient C denoising which is most suitable for the pixel. As shown in the equation (1), when the integrated de-noising coefficient C denoising is larger, the output value is determined more by the value P in of the pixel in the current frame. When the integrated de-noising coefficient C denoising is smaller, the output value is determined more by the value q of the pixel in the corresponding position in the previous frame. In other words, when the integrated de-noising coefficient C denoising in FIG. 1 is larger, the effect and strength of the filtering process for the 3D time domain are weaker. When the integrated de-noising coefficient C denoising in FIG. 1 is smaller, the effect and strength of the filtering process for the 3D time domain are stronger. One of the key figure of the present invention is how to determine the integrated de-noising coefficient C denoising most suitable for each pixel in the current frame. About the filtering function ƒ 3 , it is utilized for processing another pixel in the corresponding position in the previous frame. For example, the filtering function ƒ 3 can be the conventional de-noising filtering method of spatial domain such as the median filtering method, the bilateral filtering method, and the non-local means (NLM) filtering method, and the present invention is not limited to these filtering methods. In a preferred embodiment, the filtering function ƒ 3 is belong to an edge protection filtering method to keep the details as far as possible. [0030] The above equation (1) can be further represented in equation (2) as follows. [0000] P out =P in ׃ 1 (ƒ 2 ( C 1 ,C 2 , . . . ,C n ))+ƒ 3 ( q )×(1−ƒ 1 (ƒ 2 ( C 1 ,C 2 , . . . ,C n ))  (2) [0031] The integrated de-noising coefficient C denoising in the equation (1) is represented by ƒ 1 (ƒ 2 (C 1 , C 2 , . . . , C n )). The filtering function ƒ 1 is a global mapping function, and this function can perform a whole adjustment for the de-noising coefficient. For example, it is practical to use the filtering function ƒ 1 to perform a global gain process for an input to directly change the input strength according to the characteristics of the lens and/or the light sensing element, and generate an output to obtain the stable effect and prevent from affected by different lens, and the present invention is not limited to this condition. If the output of the filtering function ƒ 1 is larger than the input, it means that the filtering function ƒ 1 increases the input strength. If the output of the filtering function ƒ 1 is smaller than the input, it means that the filtering function ƒ 1 decreases the input strength. [0032] FIG. 2 is a diagram of a filtering function ƒ 2 in accordance with an embodiment of the present invention, wherein an input of the filtering function ƒ 2 is a number n of individual de-noising coefficients corresponding to a number n of previous frames (i.e. frame m−1˜frame m-n) of a current frame m. The individual de-noising coefficient C 1 is derived according to the current frame m and the previous frame m−1. The individual de-noising coefficient C 2 is derived according to the current frame m and the previous frame m−2, and so on, where n is a positive integer greater than or equal to 1, and if n is 1, said only refer to the previous frame. The filtering function ƒ 2 is utilized for filtering each individual de-noising coefficient C 1 , C 2 , . . . , C n to obtain the integrated de-noising coefficient C denoising . The filtering method of the filtering function ƒ 2 can be different method, such as Gaussian filtering method or median filtering method. Or, the output of the filtering function ƒ 2 can be a maximum value of C 1 ˜C n , to reduce the strength of the de-noising effect of the time domain as far as possible, so as to reduce the probability of the occurrence of the ghosting. The output of the filtering function ƒ 2 also can be a mean value of C 1 ˜C n , to average use the individual de-noising coefficients of the current frame and the number n of previous frames, so as to reduce the probability of the occurrence of the error. However, the present invention is not limited to the embodiment in FIG. 2 , or the above example. In addition, please note that the equation (2) should be performed for each pixel in the current frame, and continue to repeat the calculation when information of a next frame is received. [0033] Please refer to FIG. 3 . FIG. 3 shows a flowchart of an exemplary real-time adaptability 3D dynamic de-noising method in accordance with a first embodiment of the present invention, comprising five main steps of skin recognition, Weber-Fechner Law, motion estimation, distance condition, and 3D de-noising. Provided that substantially the same result is achieved, the steps of the process flowchart do not have to be in the exact order shown in FIG. 3 and need not be contiguous, meaning that other steps can be intermediate. In addition, some steps in FIG. 3 can be omitted according to different embodiments or design requirements. [0034] In the step 302 in FIG. 3 , the main purpose is to determine the area of the skin color. The area of the skin color is probably the human body part (especially the human face), which tends to have a larger motion, and usually is most attention by the user's eyes. Thus, the skin recognition can be utilized for prevent the human face from generating un-natural image or ghosting. The step 302 can use the conventional human face identifying method, such as using whether the values of red (R), green (G) and blue (B) channels of the pixel fit R>G>B to determine the area of the skin color. A skin color threshold value thd skin is set, wherein when an area is closer to the skin color, skin color, the skin color threshold value thd skin will be lower. When an area is not closer to the skin color, the skin color threshold value thd skin will be higher. The skin color threshold value thd skin will be utilized in the motion estimation in the step 306 . [0035] In the step 304 , the motion adjustment is performed according to the brightness based on Weber-Fechner Law. Weber-Fechner Law applied to image processing can get the following conclusion: for a fixed size of noise, in the place of the higher brightness, the noise is harder to be paid attention by the human's eyes, and in the place of the lower brightness, the noise is easier to be paid attention by the human's eyes. Thus, according to the above conclusion, a dynamic Weber threshold value thd weber is designed in the step 304 , wherein thd weber — min ≦Weber threshold value thd weber ≦thd weber — max . FIG. 4 is a relation diagram of the brightness and the Weber threshold value of the present invention. As shown in FIG. 4 , when the brightness is higher, the Weber threshold value thd weber — min is higher, and when the brightness is lower, the Weber threshold value thd weber — min is lower. The Weber threshold value thd weber — min will be utilized in the motion estimation in the step 306 . [0036] In the step 306 , a motion strength Difference between the current frame and the previous k (k=1˜n) frame is calculated. When the motion strength Difference is larger, it means that the motion level is higher, and when the motion strength Difference is smaller, it means that the motion level is lower. The motion strength Difference is defined as follows: [0000] Differece =  [ p i , j ⋯ p i , j + k ⋮ ⋱ ⋮ p i + 1 , j ⋯ p i + 1 , j + k ] * [ a i , j ⋯ a i , j + k ⋮ ⋱ ⋮ a i + 1 , j ⋯ a i + 1 , j + k ] -   [ q i , j ⋯ q i , j + k ⋮ ⋱ ⋮ q i + 1 , j ⋯ q i + 1 , j + k ] * [ a i , j ⋯ a i , j + k ⋮ ⋱ ⋮ a i + 1 , j ⋯ a i + 1 , j + k ]  ( 3 ) [0037] *is a representative of the rotating calculation, and p i,j is a representative of a current pixel of coordinate position (i,j), and q i,j is a representative of a pixel of coordinate position (i,j) in a previous frame. [0000]   [ p i , j ⋯ p i , j + k ⋮ ⋱ ⋮ p i + 1 , j ⋯ p i + 1 , j + k ] [0000] is a representative of together with the surrounding pixels to process the pixels into calculation in order to reduce the error. [0000]   [ a i , j ⋯ a i , j + k ⋮ ⋱ ⋮ a i + 1 , j ⋯ a i + 1 , j + k ] [0000] is a representative of a specific process for together with the surrounding pixels to process the pixels. For example, when the Gauss coefficient is used, [0000] [ a i , j ⋯ a i , j + k ⋮ ⋱ ⋮ a i + 1 , j ⋯ a i + 1 , j + k ]   is  [ 1 2 1 2 4 2 1 2 1 ] . [0000] That is, higher weights are allocated for the pixels to process in the middle, and lower weights are allocated for the surrounding pixels. There are details about process of filling or image for the edge or corner pixels. The details are all well known to those of average skill in this art, and thus further explanation of the details and operations are omitted herein for the sake of brevity. [0038] As mentioned above, when the motion strength Difference is larger, it means that the motion level is higher, and it means that the pixel tends to not need filtering process in time domain to reduce the side effects of the ghosting, and thus the corresponding filtering coefficient is larger. When the motion strength Difference is smaller, the corresponding filtering coefficient is smaller. A first dynamic threshold value thd dynamic1 is obtained by adding the skin color threshold value thd skin , the Weber threshold value thd weber — min , and a first predetermined threshold value thd 1 , and a second dynamic threshold value thd dynamic1 is obtained by adding the skin color threshold value thd skin , the Weber threshold value thd weber — min , and a second predetermined threshold value thd 2 , as shown in equation (4) and equation (5). [0000] thd dynamic1 =thd 1+ thd skin +thd weber   (4) [0000] thd dynamic2 =thd 2+ thd skin +thd weber   (5) [0039] The first predetermined threshold value thd 1 and the second predetermined threshold value thd 2 can be optimal values adjusted are according to the use of the lens and/or light sensing element. Next, a preposed de-noising coefficient C pre — k is obtained according to the calculated motion strength Difference. Please note that for the current frame and the previous k (k=1˜n) frames, a number n of preposed de-noising coefficients C pre — k (k=1˜n) should be obtained, respectively. FIG. 5 is a relation diagram of the motion strength and the preposed de-noising coefficient of the present invention. [0040] In the step 308 , a distance between the pixel in the current frame and the center point of the frame is calculated (i.e. Distance Condition). The purpose of the step 308 is to adjust the coefficient obtained in the step 306 according to the distance between the pixel in the current frame and the center point of the frame. In general, if the pixel is farther from the center point of the frame, the pixel will be affected by the lens shading more seriously, and thus a bigger gain is required to amplify the pixel value, which results in the pixel farther from the center point of the frame has more serious noises than the center point of the frame. Thus, the pixel farther from the center point of the frame needs stronger filtering to improve the above noises. Since the pixel farther from the center point of the frame does not belong to the images of attention due to its position, the caused side effect of the ghosting effect is less easy to be detected. When the pixel is closer to the center point of the frame, the filtering strength is weaker. In this way, in the step 308 , the corresponding adjusting coefficient R is obtained according to the information of the distance from the center point of the frame, to adjust the preposed de-noising coefficients C pre — k (k=1˜n) calculated in the step 306 . FIG. 6 is a relation diagram of the distance from the center point of the frame and the adjusting coefficient in accordance with an embodiment of the present invention, wherein the distance is calculated by two norm, that is, the distance from the center point of the frame is calculated by using the Pythagorean theorem. [0000] Distance=√{square root over (( P x −C x ) 2 −( P y −C y ) 2 )}{square root over (( P x −C x ) 2 −( P y −C y ) 2 )}  (6) [0000] P x is X coordinate of the current pixel, and P y is Y coordinate of the current pixel, and C x is X coordinate of the current pixel, and C y is Y coordinate of the current pixel. As shown in FIG. 6 , if the calculated distance Distance is shorter than a first predetermined distance r, then the adjusting coefficient R will be set to a minimum adjusting coefficient R min . If the calculated distance Distance is longer than a second predetermined distance r+k, then the adjusting coefficient R will be set to a maximum adjusting coefficient R max . If the distance is between r and r+k, then the adjusting coefficient R can be obtained by the using linear interpolation. After the adjusting coefficient R is obtained, the individual de-noising coefficient C k can be obtained by adjusting the preposed de-noising coefficients C pre — k calculated in the step 306 according to the following equation (7). [0000] C k =C pre — k *R   (7) [0041] However, the lens shading compensation method utilized by the present invention is not limited to the embodiment in FIG. 6 . For example, FIG. 7 is a relation diagram of the distance from the center point of the frame and the adjusting coefficient in accordance with another embodiment of the present invention, wherein the distance is calculated by one norm, that is, the distance from the center point of the frame is calculated by using the quadrilateral way. In any case, various modifications and alterations of the compensation method should fall into the disclosed scope of the present invention as long as they are based on the lens shading compensation. [0042] In the step 310 , the individual de-noising coefficients C k (k=1˜n) are put in the equation (2) to obtain the result P out . Please refer to the above paragraphs for the details. [0043] Please refer to FIG. 8 . FIG. 8 shows a flowchart of an exemplary real-time adaptability 3D dynamic de-noising method in accordance with a second embodiment of the present invention. The flowchart comprises all the steps in the flowchart of the real-time adaptability 3D dynamic de-noising method in FIG. 3 , but the order is changed. Specifically, the difference of the flowchart in FIG. 8 and FIG. 3 is that the distance is calculated before the Weber-Fechner Law and the motion estimation. Therefore, the equation (4) and the equation (5) are changed to be the following equation (8) and equation (9). [0000] thd dynamic1 =thd 1+ thd skin +thd dist +thd weber   (8) [0000] thd dynamic2 =thd 2+ thd skin +thd dist +thd weber   (9) [0044] A distance threshold value thd dist calculated in the step 804 is increased. Thus, provided that substantially the same result is achieved, the steps of the real-time adaptability 3D dynamic de-noising method flowchart do not have to be in the specific order, and these are all fall within the scope of the present invention. [0045] In general, in a low brightness environment, the received the pixels will be multiplied by a bigger gain before processed by the real-time adaptability 3D dynamic de-noising method of the present invention, and thus the noises will be amplified synchronously and particularly apparent. Thus, the strength of noise filtering has to be relatively increased in this condition. On the contrary, if the environmental brightness is enough, the noise is not obvious, so in this case the strength of the noise filtering should be relatively reduced, otherwise it may affect the image clarity or cause other side effects. The present invention can make optimization of adjustment according to the ambient light and brightness. In another embodiment, the steps 802 , 804 , and 806 in FIG. 8 can be omitted, as shown in FIG. 10 . [0046] Please refer to FIG. 9 . FIG. 9 is a block diagram of an image system 900 in accordance with an embodiment of the present invention. The image system 900 comprises: a lens 902 , a sensor 904 , an image and signal processor (ISP) 906 , a de-noising unit 908 , and a brightness adjusting unit 910 . For example, the lens 902 and the sensor 904 can be a part or all of a lens module. After the light enters into the sensor 904 via the lens 902 , the sensor 904 will convert the captured image to an image signal I bayer of a specific image format, wherein the specific image format is a Bayer pattern in this embodiment, but this is not a limitation of the present invention. Next, the image signal I bayer is transmitted to the ISP 906 , and the ISP 906 converts the image signal I bayer to an image signal P in of another specific image format by some image processing procedures, wherein the specific image format is a YUV signal format in this embodiment, but this is not a limitation of the present invention. Meanwhile, the ISP 906 will also further generate an automatic exposure information C ae to the brightness adjusting unit 910 . The brightness adjusting unit 910 can perform related automatic exposure algorithm according to the automatic exposure information C ae , and generate a frame rate information C fps to the de-noising unit 908 , and further generate a gain control signal C gain and a exposure control signal C exp to the sensor 904 . Next, the de-noising unit 908 will perform the de-noising algorithm according to the received image signal P in and the frame rate information C fps , so as to generate an image output signal P new — out . In general, the brightness adjusting unit 910 can be realized by firmware, and the de-noising unit 908 can be realized by software, such as a software driver, but this is not a limitation of the present invention. [0047] For the de-noising unit 908 , in order to obtain the environment light source and the environment brightness to achieve the optimal de-noising effect, the frame rate information C fps can be utilized to derive the environment light source and the environment brightness. Specifically, when the environment brightness is brighter, the frame rate information C fps will be higher. When the environment brightness is darker, the brightness adjusting unit 910 will actively increase the exposure time of the sensor 904 to lower the frame rate information C fps . In other words, when the environment brightness is brighter, the frame rate information C fps is higher than that when the environment brightness is darker. [0048] The de-noising noise unit 908 can only use the real-time adaptability 3D dynamic de-noising method in FIG. 3 or FIG. 4 without using the frame rate information C fps as one of the factors, and directly use the generated real-time adaptability 3D dynamic de-noising image output P out as an output P new — out of the de-noising noise unit 908 . Besides, the de-noising noise unit 908 also can use the real-time adaptability 3D dynamic de-noising method in FIG. 3 or FIG. 4 to calculate the de-noising image output P out and obtain an optimal output P new — out according to the frame rate information C fps . [0000] P new — out =P in ×α+P out ×(1−α)  (8) [0000] α is between 0 and 1, and used to determine the strength of the de-noising effect. The calculation of α is as follows: [0000] α=ƒ 4 ( C fps )  (9) [0049] ƒ 4 is a monotone increasing function. When the frame rate information C fps is higher, a is bigger, and the optimal output P new — out is closer to P in . That is, when the environment light source is brighter, the de-noising effect will be lower, and when the environment light source is darker, the de-noising effect will be higher. In this embodiment, the environment light source is obtained by the frame rate information C fps , but this is not a limitation of the present invention. In addition, the de-noising noise unit 908 can also use other de-noising methods with the equation (8) and the equation (9) to obtain dynamic results considering the environment light source. Above all fall within the scope of the present invention. [0050] Those skilled in the art will readily observe that numerous modifications and alterations of the device and method may be made while retaining the teachings of the invention. Accordingly, the above disclosure should be construed as limited only by the metes and bounds of the appended claims.
A decryption engine includes an update circuit, a key generator, a decryption circuit and a detection circuit. The update circuit generates a first updating information based on a premise of that a currently received frame is encrypted, and generates a second updating information based on a premise of that the currently received frame is non-encrypted. The key generator produces a first key according to the first updating information, and produces a second key according to the second updating information. The decryption circuit generates a first decrypted frame according to the first key and the currently received frame, and generates a second decrypted frame according to the second key and the currently received frame. The detection circuit detects whether the currently received frame is decrypted according to the first decrypted frame and the second decrypted frame, to generate an encryption detection result.
7
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to electronically controlled transmissions and more particularly to such transmissions having a plurality of solenoid valves grouped as a unit. 2. Description of the Prior Art Automatic transmissions for use in vehicular applications are known in which multiple forward ratios from 3 to 5 speeds at the present time. Such systems can be mechanical and hydraulic controls that are load responsive to perform the drive and gear ratio selection. Such systems include one way clutches and various planetary gear sets along with clutches and brakes that are operated in response to the operation of grouped servo valves to execute shifts without interrupting the power flow from a power source to drive wheels of the vehicle. In order to further improve transmission performance electronic transmission controls have been developed that combine electronic processing of vehicle operation to establish output signals to selectively energize the various solenoid valves to control the gear selection and for adapting the pressures within the transmission in accordance with the torque flow of the drive train. Examples of such transmissions are set-forth in U.S. Pat. No. 4,750,384. It has been proposed that such electronically controlled transmissions have their solenoid valves operated so that the clutch apply and release sequences can be programmed in a manner to eliminate the need for one way clutch devices for smoothing gear shifts in the transmission. Theoretically, such electronic controls appear to be able to produce shift smoothing without one-way clutches. In practice this has not been the experience of transmission designers. The reason for a difference between theory and practice is in part due to the fact that the solenoid controlled valves are grouped in a valve housing on one part of the outer case of the transmission. In such arrangements each of the solenoid valves that are grouped in one location on the transmission must be separately calibrated against a master. Likewise, the various clutch and brake units within the transmission must be separately calibrated. Once the clutches/brakes are assembled within a clutch housings it in turn is assembled within an outer transmission case that includes suitable internal flow patterns to connect the operating pistons of the clutch/brakes to one or more individual valves in a grouped valve arrangement thereon including the separately calibrated solenoid operated control valves. Once assembled, variations in the separately calibrated components can produce unexpected lag between apply and release control steps at the clutch/brake components and as a consequence gear shift performance can be adversely affected. It is known to provide a single solenoid controller for a clutch pack as set-forth in U.S. Pat. No. 4,750,384. However, in this arrangement the solenoid controller is mounted on the outer case of the transmission and the clutch pack is in a separate clutch housing. There is no suggestion that the solenoid controller be directly integrated within the clutch housing so that the clutch housing and solenoid controller can be calibrated as a single unit prior to assembly such that the operation thereof can be precisely determined prior to assembly. Another problem with such arrangements is that the grouped solenoid operated control valves are located in a valve housing at a single location on the outer case of a transmission. This results in different length hydraulic flow paths to actuators located at radially and axially spaced locations with respect to a common centerline through the transmission. The pressure losses in such paths further add to the difficulty in properly calibrating the fluid and mechanical components of a transmission so as to be suitable for accurate electronic control without performance lag. As a consequence the ability to affect various smoothing controls is limited not by the monitoring and electronic processing but rather by lags caused by differences in the imposition of pressure changes due to inadequate calibration. SUMMARY OF THE INVENTION The present invention includes the integration of solenoid controlled valves and clutch housings for use in automatic electronically controlled multi-speed transmissions so that they can be calibrated as a unit so as to improve friction disc pack response to electronic control signals in an electronic transmission control. An object is to provide for such integration in a configuration that will reduce lag between solenoid controlled valve operation and imposition of hydraulic pressure on the actuator for a friction disc pack. A further object is to provide for such integration by including the solenoid controlled valve within a drop in housing for a friction disc pack for controlling gear sets within an automatic transmission. A feature of the invention is to provide such reduced lag arrangements wherein the transmission has a clutch housing for gear ratio control clutch or brake of the type having a friction disc pack. Such packs have a first plurality of discs connected to a first transmission component and a second plurality of disc connected to a second transmission component. A solenoid-controlled valve and valve tracking are directly integrated into the clutch housing and the solenoid-controlled valve is responsive to an output signal from a high-speed microprocessor. The valve tracking communicates a pressurized inlet plenum within the clutch housing to a piston for actuating the friction disc pack in a manner that reduces the hydraulic lag time so as to improve the response of the clutches to pressure changes directed thereto. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a fragmentary sectional view of an integrated clutch housing and solenoid controlled valve of the present invention. FIG. 2 is a diagrammatic view of a prior art multi-speed electronically controlled transmission. DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. 2 shows a electron transmission control 10 of the prior art including a selector lever and position switch 12 and a microprocessor 14 that receives a position switch signal from the selector lever and position switch 12 . Other monitors including a program switch 16 ; kick down switch 18 throttle valve angle sensor 20 ; output rpm sensor 22 ; engine torque 24 and engine rpm 26 ; all of which direct input signals to the microprocessor 14 for processing in a known manner and wherein the microprocessor 14 is programmed in a known manner to produce output signals for selectively actuating a plurality of solenoid controlled valves 30 that are grouped at one location on the underside of a transmission housing 32 . In the past the fluid pressure from a pump is directed through valves in the grouped solenoid controlled valves and then through a passage or external line to a point of use. As shown in FIG. 1, the transmission 40 of the present invention includes a plurality of friction couplings that are operated by a piston when a pressurized fluid is directed there against. One such friction coupling is shown in FIG. 2 . In order to avoid the lag problem of the prior art, the transmission 40 includes an outer case 42 and one or more drop in brake or clutch housings 44 for one or more friction disc packs 45 . In the illustrated arrangement the drop in housing 44 has a splined inner surface 46 that is connected to externally splined plates 48 . The plates 48 are interleaved with internally splined friction discs 50 , 56 coupled to a hub portion 52 of a gear shift gear set (not shown) of a known type. The drop in housing 44 is secured with respect to the outer case 42 by being slidably engaged with an internal rib 42 a on the interior surface thereof. In accordance with the invention the drop in housing 44 is integrated with a solenoid controlled valve assembly 54 . A solenoid coil housing 56 is connected by a bracket 58 to the outer end 60 of the housing 44 . In this embodiment, the outer end 60 is formed on an annular cover 62 closing a brake housing surface 64 that can have a plurality of suitable passages therein for feeding one or more brake units if desired. The cover 62 and housing 44 have a valve track bore 66 formed therethrough. The bore 66 has a suitable seal gland 68 at the outboard end thereof. It receives a valve track 70 therein with spaced shoulders 72 , 74 , 76 sealed against the bore 66 to form annular cavities 78 and 80 . The housing 44 includes an inlet passage 82 connected to a source of pressurized actuating fluid directed to cavity 78 . The cavity 80 connects to an outlet passage 84 in the housing 44 that is communicated with a piston bore 86 therein. The piston bore 86 receives an actuating piston 88 that will be acted upon by pressure from the inlet 88 to engage the friction disc pack 45 . When the actuation pressure is connected to an exhaust 90 in the controller 54 the piston 88 is biased by a return spring 92 so as to disengage the plates 48 and friction discs 50 of the pack 45 . The control of pressurized fluid within the controller 54 is by a valve element 92 of a known type with suitable lands thereon that seal against an internal bore 94 to control flow between the inlet passage 82 , the outlet passage 84 and the exhaust 90 via openings 96 , 98 in the valve track 70 and as is known by those skilled in the prior art. The solenoid operated control valve 54 is connected to a high speed microprocessor and because it is directly integrated on the housing 44 can be calibrated to accurately process outputs from such a microprocessor to produce a no lag response to brake engagement and release to produce a desired control of an associated gear set. The solenoid operated control valve 54 will respond to output signals to shift the valve element 92 connected thereto within the valve track 70 such that pressurized flow from the transmission pump will be directly applied to the brakes such that the speed range of the multi-speed gear set can be adjusted smoothly in response to a variety of desired operating programs. The invention has been described in an illustrative manner. It is to be understood that the terminology, which has been used, is intended to be in the nature of words of description rather than of limitation. Many modifications and variations of the invention are possible in light of the above teachings. Therefore, within the scope of the appended claims, the invention may be practiced other than as specifically described.
An electronically controlled transmission has microprocessor and a clutch housing including an integrated solenoid controlled valve; the clutch housing including a valve track operatively receiving a valve element connected for operation by the integrated solenoid controlled valve; and a friction disc pack within the clutch housing having a piston actuator pressurized by fluid flow regulated by operation of the integrated solenoid controlled valve in response to electronic control signals from the microprocessor.
5
BACKGROUND OF THE DISCLOSURE The present invention relates to a vehicle power window device for opening and closing of a vehicle window glass, and more particularly to an improved vehicle window regulator thereof. A conventional general vehicle power window device is a device composed of an electric motor acting as a driving source, a vehicle window regulator for opening and closing a window glass by means of transmission of a torque of the electric motor, and a switching circuit for operating the electric motor so as to open and close automatically the window glass of a vehicle or the like. Switches of the switching circuit are provided collectively in a driver's seat and in each passenger's seat so that each window glass can be opened to a given position. Accordingly, a driver and passengers can open and close the each window glass to a given position from a driver's seat and passengers' seats by means of operation of the driver's seat switches and the passengers' side switches. As an example of such a vehicle power window device, FIG. 2 illustrates the state that the window glass rises and closes completely in case that the vehicle power window device is assembled in the right door facing a vehicle-running direction. The vehicle window regulator uses an electric motor 1 as a driving source and the electric motor 1 is decelerated by a uniform velocity gear train using a sector gear provided in a regulator base 3 fixed inside a door, swinging a regulator arm 5 to open and close the window glass 7. A spiral spring 19 is also provided in the regulator base 3 so as to balance the weight of the window glass 7. The window glass 7 is supported by a front runway 9 and a rear runway 11 so as to be able to rise and fall. A movable rail 13 is fixedly attached to an lower part of the window glass 7. A sliding pin 5p which slides in a slit 13a of the movable rail 13 is fixedly attached to an end of the regulator arm 5. A sub-arm 15 is swingably supported almost at a center of the regulator arm 5. The sub-arm 15 is provided in order that the window glass 7 is prevented from leaning and actuates smoothly. A fixed rail side arm 15a and a movable rail side arm 15b are incorporated by means of a caulking or the like. A sliding pin 15p which slides in a slit 17a of a fixed rail 17 is fixedly attached to an end of the fixed rail side arm 15a by means of a caulking or the like, and a sliding pin 15q which slides in a slit 13b of a movable rail 13 is fixedly attached to an end of the movable rail side arm 15b by means of a caulking or the like. In case of a conventional vehicle power window device, the uniform velocity gear provided in the regulator base 3 decelerates at a fixed rate. In case of a conventional vehicle power window device as constructed above, because the uniform velocity gear train provided in the regulator base decelerates at a fixed rate, the regulator arm also swings at a fixed angular velocity, thus opening and closing a window glass completely at an invariable velocity. Accordingly, it is difficult to open the window glass only slightly from a complete-closed state and a switch operation must be repeated so as to close the window glass again when the window glass opens to excess. As a result thereof, a driver's attention is especially distracted by the above operation, which causes a possibility of negligent driving of the driver. One method which is considered for the purpose of avoiding those difficulties is to control electrically not only the opening and the closing of the window glass, but also the velocity of opening and closing by means of a switching circuit. However, the method involves a gain in weight and an increase in cost. SUMMARY OF THE INVENTION It is an object of the present invention to provide a vehicle window regulator which has a simple structure so as to avoid a gain in weight and an increase in cost. It is another object of the present invention to provide a vehicle window regulator which enables a window glass to open and close slowly from a complete-closed position. It is a further object of the present invention to provide a vehicle window regulator which enables a window glass to open and close fast besides a complete-closed position side of the window glass. The vehicle window regulator which is provided by the present invention is characterized by being so constructed as to open and close the window glass slowly enough on a complete-closed position side by using a non-uniform velocity rate gear train to transmit an intermediate shaft driven by the electric motor to a driving shaft of a regulator arm which opens and closes the window glass. In the vehicle window regulator of the present invention which is constructed as above, a non-uniform velocity rate gear train is used to transmit an intermediate shaft driven by an electric motor or a manual operation to a driving shaft of a regulator arm for opening and closing of a window glass, so that while the intermediate shaft is driven at a fixed angular velocity by the electric motor or the manual operation, an angular velocity of a swinging shaft of the regulator arm is so changed that the window glass opens and closes slowly enough on the complete-closed position side of the window glass. Further, the angular velocity of the swinging shaft of the regulator arm is so changed that the window glass opens and closes fast besides the complete-closed position side of the window glass, or a complete-open position side and a middle position. Other and further objects, features and advantages of the invention will become appear more fully from the following description. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1(a) is a front view illustrating a state that a window glass is about to close completely in a vehicle window regulator of an embodiment of the present invention. FIG. 1(b) is a front view illustrating a state that the window glass is about to open completely in said regulator. FIG. 2 is a perspective view illustrating a structure of a conventional general vehicle window regulator. FIG. 3(a) is a schematic front view illustrating a combination of an eccentric circular gear and a non-circular gear in a non-uniform velocity rate gear train of the present embodiment. FIG. 3(b) is a graph showing a relationship between a rotary angle θ 1 through which the eccentric circular gear makes one rotation at a fixed angular velocity ω 1 and an angular velocity ω 2 of said non-circular gear which rotates while meshing with the eccentric circular gear. FIG. 4(a) is a schematic front view illustrating a non-uniform velocity rate gear train of a second embodiment. FIG. 4(b) is a graph showing a relationship between a rotary angle of an intermediate shaft and an angular velocity of a driving shaft in the second embodiment. FIG. 5(a) is a schematic front view illustrating the non-uniform velocity rate gear train of a third embodiment. FIG. 5(b) is a graph showing a relationship between the rotary angle of the intermediate shaft and the angular velocity of the driving shaft in the third embodiment. FIG. 6(a) is a schematic front view illustrating the non-uniform velocity rate gear train of a fourth embodiment. FIG. 6(b) is a graph showing a relationship between the rotary angle of the driving shaft and the angular velocity of the driving shaft. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to FIGS. 1 to 3, there is shown therein an embodiment of the present invention. The present embodiment is a partly modified embodiment of a conventional gear train provided in a regulator base of a vehicle window regulator of the type illustrated in FIG. 2. In the present embodiment, each structure element and a position relation as illustrated in FIG. 2 are the same as conventional ones, therefore a structure of the present embodiment is explained referring to FIG. 1(a), FIG. 1(b) and FIG. 2. The vehicle window regulator of the present embodiment uses an electric motor 1 as a driving source and the electric motor 1 is decelerated by a gear train 23, 27, 29 and 31 provided in a regulator base 3 fixed inside a door, swinging a regulator arm 5 around a driving shaft 33 to open and close the window glass 7. A spiral spring 19 is provided between the regulator base 3 and a driving shaft 33 so as to balance the weight of the window glass 7. The window glass 7 is supported by a front runway 9 and a rear runway 11 so as to be able to rise and fall. A movable rail 13 is fixedly attached to an lower part of the window glass 7. A sliding pin 5p which slides in a slit 13a of the movable rail 13 is fixedly attached to an end of the regulator arm 5. A sub-arm 15 is swingably supported almost at a center of the regulator arm 5. The sub-arm 15 is provided in order that the window glass 7 is prevented from leaning and actuates smoothly. A fixed rail side arm 15a and a movable rail side arm 15b are incorporated by means of a caulking or the like. A sliding pin 15p which slides in a slit 17a of a fixed rail 17 is fixedly attached to an end of the fixed rail side arm 15a by means of a caulking or the like, and a sliding pin 15q which slides in a slit 13b of a movable rail 13 is fixedly attached to an end of the movable rail side arm 15b by means of a caulking or the like. In respect to construction of the vehicle window regulator as illustrated in FIG. 2, FIG. 1(a) illustrates a state wherein the window glass is about to close completely and FIG. 1(b) illustrates a state wherein the window glass is about to open completely. A worm wheel meshing with a worm (not illustrated) fixedly attached to an electric motor 1 and a pinion 23 are fixedly attached to a worm wheel shaft 21 by means of a caulking or the like. An intermediate gear 27 meshing with the pinion 23 and an eccentric circular gear 29 are fixedly attached to an intermediate shaft 25 by means of the caulking or the like. A non-circular gear 31 meshing with the eccentric circular gear 29 is fixedly attached to the driving shaft 33 in the regulator arm 5 fixedly attached to the regulator arm shaft 15s by means of the caulking or the like. The non-uniform velocity rate gear train using the non-circular gear is illustrated in FIG. 3(a). FIG. 3(a) illustrates a meshing state of the eccentric circular gear 29 fixedly attached to the intermediate shaft 25 and the non-circular gear 31 fixedly attached to the driving shaft 33. The eccentric circular gear 29 uses a portion of a spur gear 29a as an eccentric gear. The non-circular gear 31 meshing with the eccentric circular gear 29 uses a portion of a conjugated wheel 31a. FIG. 3(b) illustrates the change in angular velocity ω 2 at which the non-circular gear 31 rotates for a rotary angle θ 1 through which the eccentric circular gear 29 makes one counterclockwise rotation at a fixed angular velocity, starting from the state as illustrated in FIG. 3(a). The ratio of the angular velocity ω 1 to ω 2 is inversely proportional to r 2 /r 1 the ratio of the distances or radii r 1 and r 2 from each rotary center to meshing position and ω 2 α r 1 /r 2 is in proportion because of the fixed angular velocity ω 1 . As illustrated in FIGS. 3(a) and 3(b), when the rotary angle θ 1 of the eccentric circular gear 29 is 0°, the angular velocity ω 2 of the non-circular gear 31 reaches its minimum and when the rotary angle θ 1 is 180°, the angular velocity ω 2 reaches its maximum. In the present embodiment, the window glass closes completely when the rotary angle θ 1 of the eccentric circular gear 29 is 0° and the window glass opens completely when the rotary angle θ 1 of the eccentric circular gear 29 is about one hundred degrees. The rotary angles of 0° to about 100° suffices the meshing of the both gears, therefore the eccentric circular gear 29 and the non-circular gear 31, which are illustrated in FIG. 3(a) by solid lines, are used in a practical structure. While the angular velocity ω 1 of the eccentric circular gear 29 is invariable both near the complete-closed position of window glass as illustrated in FIG. 1(a) and near the complete-open position of window glass as illustrated in FIG. 1(b) because the decelerated rate of the motor is constant, the non-circular gear 31 and the regulator arm 5 have a fairly different angular velocity ω 2 from the angular velocity ω 1 , so that a movable rail 13 driven by the regulator arm 5 actuates so as to open and closes the window glass 7 slowly enough near the complete-closed side. (ACTUATION OF THE EMBODIMENT) According to the above construction, when a motor 1 rotates at a fixed velocity, a worm wheel shaft 21 also rotates at a fixed angular velocity. When the worm wheel shaft 21 rotates at a fixed velocity, a pinion 23 also rotates at a fixed velocity, thereby rotating an intermediate gear 27 which meshes with the pinion, an intermediate shaft 25 and an eccentric circular gear 29 at a fixed velocity. Just before a window glass 7 closes completely, the eccentric circular gear 29 rotates clockwise, as shown by an arrow A of a solid line in FIG. 1(a) and a non-circular gear 31 rotates counterclockwise on a driving shaft 33, as shown by an arrow B of a solid line. The angular velocity ω 2 of the non-circular gear 31 becomes slow, because θ 1 approaches 0°. When the non-circular gear 31 rotates counterclockwise on the driving shaft 33, a regulator arm 5 also rotates counterclockwise on the driving shaft 33, as shown by an arrow C of a solid line. A movable rail 13 and a window glass 7 are pushed up smoothly via a sliding pin 5p by the regulator arm 5, as shown by an arrow D of a solid line. The sliding pin 5p moves to left in FIG. 1(a) within a slit 13a of the movable rail 13, as shown by a solid-line arrow E. When the movable rail 13 rise, a sub-arm 15 rotates clockwise, moving a sliding pin 15q to right in FIG. 1(a) within a slit 13b and also a sliding pin 15p to left in FIG. 1(a) within a slit 17a of a fixed rail 17. In order to open the window glass 7, a motor 1 is energized in a reverse direction. The eccentric circular gear 29, the non-circular gear 31, the regulator arm 5 and the movable rail 13 move in a direction contrary to the direction described above, as shown by dotted-line arrows A, B, C and D. When the window glass opens from a complete-closed position, an angular velocity ω 2 of the non-circular gear 31 is so slow similiarly when θ 1 approaches 0°, that the window glass 7 falls slowly at first. Thus, the present invention enables the window glass 7 to open slightly from the complete-closed position. When the motor 1 continues to be energized in the reverse direction, the regulator arm 5 rotates clockwise, continuing to fall the movable rail 13, the movable rail 13 thus pass a position of the fixed rail 17 in a direction shown by the arrow D as illustrated in FIG. 1(a). As illustrated in FIG. 1(b), when the movable rail 13 reaches a lower end position, the window glass 7 opens completely. As illustrated in FIG. 3(b), the rotary angle θ 1 of the eccentric circular gear 29 widen gradually for 100° or an open side, and the angular velocity ω 2 of the non-circular gear 31 also widens, so that the window glass 7 opens and closes fast. Because the vehicle window regulator of the present embodiment substitutes the non-uniform velocity rate gear train for a part of the conventional uniform velocity gear train without the need of a circuit for controlling an opening and closing velocity of the window glass, the number of a part is the same as the conventional one, so that a cost for the part and the assembly can be prevented from increasing. Moreover, the vehicle window regulator can be rotated not only by a motor, but also by a manual operation. (OTHER EMBODIMENT) The present invention is not intended to be limited to details of the above embodiment, therefore an elliptic gear may or a logarithmic helical gear may be used as a non-circular gear employed to transmit an intermediate shaft driven by an electric motor or a manual operation to a driving shaft of a regulator arm for opening and closing a window glass. In a second embodiment as illustrated in FIG. 4(a), a non-uniform velocity rate gear train is composed of two elliptic gears 34 and 35 provided shafts 25 and 33 in each focal position. In the elliptic gears 34 and 35, unnecessary parts for meshing are eliminated. As shown in a velocity rate curve of the elliptic gears 36 and 35 as illustrated in FIG. 4(b), in the same manner as a first embodiment, a velocity rate ω 2 /ω 1 reaches its maximum when a rotary angle θ 1 of the elliptic gear 34 is 180°. According to the second embodiment, gears with common shapes can be used and the elliptic gears are comparatively easy to manufacture. In the third embodiment as illustrated in FIG. 5(a), the non-uniform velocity rate gear train is composed of the two elliptic gears 36 and 37 which provide an intermediate shaft 25 and a driving shaft 33 on a geometrical center. In the elliptic gears 36 and 37, unnecessary parts for meshing are eliminated. As shown in a velocity rate curve of the elliptic gears 36 and 37 as illustrated in FIG. 5(b), the velocity rate ω 2 /ω 1 reaches its maximum when the rotary angle θ 1 of the elliptic gear 35 is 90°. In a fourth embodiment as illustrated in FIG. 6(a), the non-uniform velocity rate gear train is composed of two logarithmic helical gears 38 and 39 which provide the intermediate shaft 25 and the driving shaft 33 on a logarithmic helical center. In the logarithmic helical gears 29 and 31, unnecessary parts for meshing (two-point chain line parts) are connected by a straight line like a solid line. In the fourth embodiment, gears with common shapes can be used and there are combinations for several functional relations. Although the invention has been described in its preferred form with a certain degree of particularlity, it is understood that the present disclosure of the preferred form has been changed in the details of construction and the combination and arrangement of parts may be resored to without departing from the spirit and the scope of the invention as hereinafter claimed.
A vehicle window regulator displaces a window at a faster speed when the window is near its fully closed position than when the window is near its fully open position. The speed is controlled by the meshing of the peripheries of two gears, each periphery defining a varying radius about its axis of rotation. The gear peripheries can be of different shapes, such as circular eccentric, elliptical and logarithmically helical. One of the gears is driven by a constant speed electric motor.
5
FIELD OF THE INVENTION The present invention relates to reciprocating pumps and more particularly, the present invention relates to an improved pump linkage including a break rod for a fail-safe operation. BACKGROUND OF THE INVENTION Reciprocating piston pumps such as triplex pumps are well known in the art. Such pumps commonly employ a linkage including a crankshaft attached at one end to a rotating drive wheel or gear and at the other end to a crosshead slideably engaged in a lateral guide for converting the rotary motion of a drive into reciprocal motion of the crosshead. The crosshead is then connected to a pump piston or plunger via appropriate smaller diameter connecting rods. As is well known, longitudinal alignment of the pump linkage is critical for extended operation of the pump since any misalignment imposes friction and flexure stresses particularly in the connecting rods. Over time even in closely aligned pumps, the linkage will eventually fail. It is hypothesized that stresses due to the constant reciprocation against pressure cause gradual hardening and embrittlement of the rods until one of them fails by breaking in two. While a periodic downtime for replacement of the broken rod is expected, the broken rod can sometimes result in damage to other components of the pump assembly. In addition, replacement of a broken rod can become difficult if substantial disassembly of the pump is required. Further, if the broken rod is an integral part of another component of the linkage (such as the crosshead), it may also be necessary to replace an expensive pump component which is otherwise in good condition. Thus, there is a need for a pump linkage adapted to fail predictably. The linkage upon failure should not damage other components and be easily repaired with minimum downtime. U.S. Pat. No. 4,566,370 to Hanifi discloses a reciprocating piston pump driven by a rotating drive via a crankshaft including a crosshead, a transfer rod and a piston. The connection between the transfer rod and the piston is said to ensure a certain lateral and angular moveability so as to avoid any distortion or twisting forces which could otherwise result in misalignment of the piston, crosshead and transfer rod. U.S. Pat. No. 1,037,840 to Wintzer discloses a reciprocating piston in a cylinder driven by a rotating driver via a crankshaft, crosshead and piston rod. U.S. Pat. No. 3,276,390 to Bloudoff et al. discloses a reciprocating pump driven by a rotating driver. A plunger is connected to a plunger mandrel by a bolt having a reduced cross section. The mandrel has a flange which is attached to a flange of an intermediate rod by a clamp wherein the intermediate rod is threadedly engaged to a crosshead. It is stated that under excessive loads breakage will occur at the bolt. Further damage which can occur on continued stroking is said to be limited to parts which are relatively inexpensive and easily replaceable. U.S. Pat. No. 1,557,222 to Warner discloses a reciprocal pump apparatus powered by a rotating drive wheel having an eccentrically attached crankshaft. The crankshaft is pivotably connected to a reciprocating crosshead which, in turn, is connected to a piston rod. The crosshead rides in a cross guide and a threaded end of the piston rod engages a threaded bore in the crosshead. SUMMARY OF THE INVENTION By installation of a break rod in a pump linkage, a reciprocal pump of the present invention can be adapted for fail safe operation. By fail-safe, it is meant that the failure will occur after an extended period of operation at a predetermined location in the linkage. Upon failure, the break rod can be easily replaced to reduce pump turn-around time. As one embodiment, the present invention provides a reciprocating pump linkage for mechanically connecting a piston rod of a pump unit to a crosshead member of a drive unit. The linkage comprises a crosshead extension rod having a proximal end removably secured the crosshead member and a distal end comprising a coaxial bore. A break rod having a proximal end received in the bore of the crosshead extension rod and a distal end for coupling the piston rod is provided for defining a fail-safe break point in the linkage. The proximal end of the break rod preferably has a smaller cross-sectional area than the distal end of the crosshead extension rod. Alternatively, the proximal end of the break rod comprises a weaker material of construction than the distal end of the crosshead extension rod. In a preferred embodiment, adjacent ends of the break rod and crosshead extension rod are threadably connected. The distal end of the break rod is releasably connected to the piston rod. Adjacent ends of the break rod and piston rod comprise matching flanges connected by a clamp. The proximal end of the crosshead extension rod includes a flange bolted to the crosshead at an axial distal surface. The proximal end of the break rod has a threaded portion having a greater number of threads than the bore of the crosshead extension rod. The threaded portion of the break rod has a tapped coaxial bore extending the threaded length thereof for decoupling a severed threaded portion from the bore in an event of a failure of the break rod. The distal end of the crosshead extension rod has a diameter portion adapted for engagement with a box wrench. In another embodiment, the present invention provides a method for repairing a reciprocal pump incorporating the inventive fail-safe break rod following an ordinary failure thereof. As a first step, a severed break rod threaded portion is decoupled from the crosshead extension rod bore. An associated severed break rod flanged portion is unclamped from connection with the piston rod. A new break rod is installed between the crosshead extension rod and the piston rod. The repaired linkage is suitably axially aligned to inhibit stress therein during pump operation. The break rod installing step includes threadably coupling the break rod threaded portion to the crosshead extension rod bore, and clamping the break rod flange to the piston rod flange. After failure, the decoupling step includes inserting an appropriate tool into the tapped coaxial bore in the severed break rod threaded portion. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic representation of a cross-sectional elevational view of a reciprocating pump incorporating the fail-safe linkage of the present invention. FIG. 2 is an schematic, partial cross-sectional view of the present invention of FIG. 1 showing the linkage crosshead extension rod and an associated break rod. FIG. 3 is a schematic top view detail of the crosshead extension rod and break rod of FIG. 2 in an unconnected state. DETAILED DESCRIPTION OF THE INVENTION A reciprocal pump is adapted for fail-safe operation by installation of a break rod in the pump linkage. Upon failure, the broken rod can be quickly replaced for reduced pump downtime and maintenance costs. Referring to FIGS. 1-3, a pump assembly shown generally as 10 comprises a drive unit A mechanically connected by a linkage B to a pump unit C. As is well known in the art, the drive A comprises a drive wheel 12 turned by rotary drive means such as an electric motor and reduction gears (not shown) enclosed in a housing 14. The housing 14 typically includes a flanged head 15 bolted thereto by bolts 17. To convert rotating action of the drive A into the reciprocating action of the pump C, the linkage B includes a crankshaft 16 connected at a one end to the drive wheel 12 by a first pin 18. At the other end, the crankshaft 16 is pivotably connected to a crosshead 20 by a second pin 22. The crosshead 20 slides reciprocally within parallel guides 24 integral with the housing 14. The crosshead 20 includes an outer distal surface 26 suitable for the connection of a crosshead extension rod 28. While any connecting means can be employed, the crosshead extension rod 28 is preferably connected to the crosshead 20 by flange 30 formed at a proximal end 31 thereof. The flange 30 is bolted at the crosshead surface 26 by bolts 32. The crosshead extension rod 28 includes a distal end 34 received in an opening 36 in the drive housing 14 and extending into the pump unit B. The opening 36 is preferably sealed by a bushing seal 37 to inhibit flow of lubrication fluid from the drive housing 14 to the pump unit B. The distal end 34 of the crosshead extension rod 28 is adapted for connection to a break rod 38. Thus, the extension rod 28 has an internal threaded bore 40 for connection to a complementary external threaded portion 41 at a proximal end 42 of the break rod 38. The threaded portion 41 preferably has a greater number of threads than the bore 40. The crosshead extension rod distal end 34 is preferably provided with a diameter section 43 having a square or hexagonal transverse cross-section adapted for engagement with a box wrench, for example, to facilitate threaded connection of the break rod 38. The distal end 44 of the break rod 38 includes a flange 46 for connection to a complementary flange 48 at a proximal end 50 of piston rod 52. A clamp 54 preferably secures the flanges 48, 52 to ensure the maintenance of proper alignment in the linkage B during the operation of the pump 10. Preferably, a gap between flanges 48, 52 when connected is on the order of about 0.001 inches or less. In accordance with the present invention, the break rod 38 is mechanically weaker than the other members of the linkage B preferably due to a smaller diameter. A juncture 55 at which the break rod 38 is connected to the crosshead extension rod 28 thus provides a point of predictable mechanical failure in the break rod 38. The break rod can also be made from a mechanically weaker material than other components of the linkage B. In a preferred embodiment, the break rod threaded portion 41 includes a tapped coaxial bore 56 extending the length thereof to facilitate removal of the threaded portion 41 from the threaded bore 40 of the crosshead extension rod 28 following failure of the break rod 38. As is conventional in the art, the pump unit C comprises a piston 58 connected at a distal end of the piston rod 52. The piston 58 is disposed in a cylinder 60 coaxial with the linkage B for slidable engagement therein. The cylinder 60 is generally mounted in a pump housing 62. In the practice of the present invention following failure of the break rod 38, the severed portions can be removed and a new rod can be installed without disassembly of the crosshead 20 and the cylinder 60. Specifically, following a fracture from the distal end 44 the threaded portion 41 is extracted from the bore 40 in the crosshead extension rod 28 by a conventional thread extraction tool inserted into the tapped bore 56. The distal end 44 including the flange 46 separated from the threaded portion 41 by the failure of the break rod 38 is unclamped from the piston rod 52. A new break rod is installed by initially threadably coupling the break rod threaded portion 41 to the extension rod bore 40 and clamping the new break rod flange 46 to the piston rod flange 48 so that the linkage B maintains the crosshead 20 and the piston 58 in close alignment along the pump axis. The foregoing description of the invention is illustrative and explanatory thereof. Various changes in the materials, apparatus, and particular parts employed will occur to those skilled in the art. It is intended that all such variations within the scope and spirit of the appended claims be embraced thereby.
Disclosed are a fail-safe linkage for a reciprocating pump and a method for repairing the pump following failure of the linkage. The pump linkage includes a break rod inserted between the crosshead and piston rod so that an inevitable failure of the linkage occurs predictably in the break rod. In such a manner, pump downtime can be reduced following failure since the break rod can be easily replaced without extensive disassembly of the pump.
5
BACKGROUND OF THE INVENTION [0001] This invention relates to a combustor, and more particularly to an integrated polymeric-ceramic membrane-based oxy-fuel combustor. [0002] Carbon capture is essential to continue the use of fossil fuels while reducing the emissions of CO 2 into the atmosphere. Oxy-fuel combustion is an emerging methodology for carbon capture in power and steam generation systems. In oxy-fuel combustion, the fuel is burned in a nitrogen-free environment (pure oxygen diluted with CO 2 and H 2 O) instead of air. Thus, the flue gas mainly consists of CO 2 and H 2 O that can be easily separated through condensation of H 2 O. In order to moderate the gas temperature in the absence of N 2 , part of the flue gases including CO 2 is recycled back to the combustion chamber. Among different methods for O 2 production, membrane separation is well suited for small-scale and oxygen-enriched air requirements [1, 2]. Membrane separation material options generally fall into one of two categories, polymeric or ceramic. These two membrane types provide very different performance and operating characteristics. The first, polymer membranes, operate at ambient temperatures. Polymer membranes [3] are usually considered for producing O 2 -enriched air. Polymer membranes and/or zeolites are good for oxygen separation. However, the purity of oxygen is not high, in particular not sufficiently high for oxyfuel combustion with efficient carbon capture. The second type is the high-temperature ceramic membrane or Ion Transport Membranes (ITM). Ceramic membranes produce very high purity oxygen, but they require high operating temperatures [4] and have higher material cost per productivity [5]. The permeability (oxygen flux rate) of ITMs depends on the partial pressure of O 2 in the oxygen-nitrogen mixture. Increasing the concentration of O 2 by using O 2 -enriched air rather than air improves the performance of the ITM. Combining polymeric with ceramic membranes can, thus, improve the overall efficiency of the system. SUMMARY OF THE INVENTION [0003] The invention disclosed herein is a combustor including a polymer membrane structure for receiving air at an input and for delivering oxygen-enriched air at an outlet. An oxygen transport reactor including a ceramic ion transport membrane receives the oxygen-enriched air from the polymer membrane structure to generate oxygen for combustion with a fuel introduced into the oxygen transport reactor. In a preferred embodiment, the oxygen-enriched air from the polymer member structure is compressed and heated before being received by the oxygen transport reactor. The oxygen transport reactor may include a cylindrical ion transport membrane with the oxygen-enriched air flowing along the outside of the ion transport reactor and with fuel flowing along the inside. In this embodiment, means are provided for introducing CO 2 along with fuel into the oxygen transport reactor. It is preferred that the oxygen-enriched air and fuel flow in opposite directions. [0004] In another embodiment, the energy for compressing and heating of the oxygen-enriched air comes from expansion of flue gases from the reactor in a turbine device. It is also contemplated to introduce nitrogen-enriched air that was separated from the oxygen-enriched air into a turbine for power production. In a particularly preferred embodiment, the polymer membrane structure and the oxygen transport reactor are integrated into a single unit. BRIEF DESCRIPTION OF THE DRAWING [0005] FIG. 1 is a schematic illustration showing air separation in a polymer membrane structure. [0006] FIG. 2 is a schematic illustration of a single oxygen transport reactor. [0007] FIG. 3 is schematic illustration of the combustor disclosed herein including a polymer membrane structure and oxygen transport reactors. [0008] FIG. 4 a is a cross-sectional view of the combustor according an embodiment of the invention. [0009] FIG. 4 b is a side view of the combustor shown in FIG. 4 a along the lines A-A. [0010] FIG. 5 is a schematic diagram of an experimental setup and sample for oxygen permeation measurement. [0011] FIG. 6 is a schematic diagram of an oxygen permeation membrane used in the experiments. [0012] FIG. 7 is an SEM image of the surface of a membrane at the feed side after permeation measurements. [0013] FIG. 8 is a graph of oxygen permeation flux against temperature showing experimental results for the influence of the partial pressure of oxygen in the feed side on the oxygen flux permeation across a membrane at different membrane temperatures. [0014] FIG. 9 is a graph showing experimental results and numerical results for the influence of the partial pressure of oxygen in the feed side on the oxygen flux permeation across a membrane. [0015] FIG. 10 is a schematic illustration of a hybrid polymer-ceramic free-carbon gas turbine unit according to an embodiment of the invention. DESCRIPTION OF THE PREFERRED EMBODIMENT [0016] Integrating polymeric and ceramic membranes with combustion systems such as gas turbine combustion chambers [6-9] can provide a high temperature environment and high oxygen flux rates. Fuel on the permeate side of the membrane reacts with any oxygen that is transported through the ITM resulting in very low oxygen concentration on the permeate side. Thus, large concentration gradients across the membrane are maintained achieving high fluxes of oxygen. Moreover, fuel oxidation converts chemical to thermal energy and maintains the high temperature required to activate the materials of the oxygen transport membrane. In order to improve the permeability of O 2 , O 2 -enriched air is used instead of air. The O 2 -enriched air is produced via polymer membranes. Thus, air is separated in the polymer membrane into O 2 -enriched air and N 2 -enriched air. Polymer membrane separators are combined in series with the oxygen transport reactors such that the polymer membrane is used to produce O 2 -enriched air, which is then fed to oxygen transport reactors. Alternatively, the polymer membranes can be integrated with the oxygen transport reactors such that the oxygen is enriched in the polymer membrane, separated in the ion transport membrane and burned with fuel all in one component. [0017] In the present invention, a highly efficient carbon-free combustor is disclosed. The combustor comprises two basic components as shown in FIGS. 1 and 2 . As shown in FIG. 1 the first component is a polymer membrane structure 10 that produces oxygen-enriched air. The second component is an ion transport membrane (ITM) 12 as shown in FIG. 2 and is used to produce high quality oxygen. The two components 10 and 12 efficiently provide high purity oxygen to burn with fuel thereby producing carbon dioxide and water vapor. The water vapor is separated following expansion and heat extraction and CO 2 is captured. Thus, the combustor is a hybrid polymer-ceramic carbon-free unit. [0018] With reference now to FIG. 3 , the combustor 14 includes a set of polymer membranes 10 and a set of oxygen transport reactors 12 . The polymer membranes 10 are used to produce O 2 -enriched air. In operation, compressed air is introduced into the polymer membranes 10 and is separated into oxygen-enriched air 16 and nitrogen-enriched air 18 . The objective is to produce air with a high concentration of O 2 . The oxygen-enriched air is compressed in a compressor 20 and heated in a heat exchanger 22 before being passed to the oxygen transport reactors 12 . The nitrogen-enriched air 18 leaves the polymer membrane 10 for use in other purposes such as for fertilizers or for firefighting applications. [0019] The oxygen transport reactor (OTR) 12 includes a cylindrical ion transport membrane (ITM) in which fuel flows inside the cylindrical membrane and O 2 -enriched air flows outside, surrounding the outer surface of the membrane. Oxygen-enriched air is obtained using the polymer membrane 10 as shown in FIG. 1 . [0020] The rate at which oxygen is separated depends on the partial pressure difference of O 2 across the membrane. Utilizing the polymer membrane 10 allows the production of oxygen-enriched air (around 80%) thereby increasing the partial pressure of O 2 on the outer side of the ITM by approximately four times. Thus, the flux of O 2 across the ion transport membrane (ITM) 12 is increased significantly. The continuous combustion of oxygen as it is transported through the membrane 12 thickness, with fuel, results in a continuous low oxygen partial pressure at the inside surface of the membrane 12 . Thus, the ratio of the partial pressures of the oxygen across the sides of the membrane remains high so as to ensure a high flux rate of oxygen separation. [0021] In the combustor disclosed herein, fuel is burned in high quality oxygen resulting from the separation of oxygen by the hybrid polymer and ceramic system. This configuration is expected to result in elevated temperatures of the exhaust gases at the exit of the combustor. In order to provide the ballasting effect that would have been provided by the absent nitrogen and to moderate the exhaust gas temperatures, part of the carbon dioxide in the flue gas 24 (CO 2 and H 2 O) is recycled in the combustion chamber and is mixed with the fuel. Recycling part of the flue gases and mixing them with the fuel provides preheating of the fuel and, thus, provides high temperature in the entrance region of the combustor. High temperature is required to enhance the oxygen flux across the membrane thickness at the entrance region in particular. High temperature is also essential for combustion stability in the entrance region of the combustor. This arrangement also serves to achieve constant temperature distribution along the ceramic membrane 12 and thereby minimizes the stress on the membrane 12 . The mixing of CO 2 with fuel enables purging of oxygen and ensures low oxygen concentration in the fuel side thereby enhancing the process of oxygen separation in the air side and increasing the oxygen flux rate in the region close to the inlet section of the fuel flow. [0022] Still referring to FIG. 3 , compressed oxygen-enriched air is circulated in a direction that is opposite to that of the fuel flow. Thus, air is heated from the combustion gases as they flow from inlet of the combustor toward the combustor outlet and the oxygen-enriched air is heated to provide high temperature of the membrane at the inlet of the combustor thereby enhancing the rate of oxygen flux in the region. The opposite flow arrangement also serves to achieve constant temperature distribution along the ceramic membrane to minimize stress on the membranes. [0023] The oxygen-enriched air produced by the polymer membrane 10 is compressed in the compressor 20 before being passed to the oxygen transport reactor 12 . In order to enhance overall system efficiency, the compressed oxygen-enriched air is heated in the heat exchanger 22 . The energy required is obtained from the expansion of the flue gases containing CO 2 and H 2 O in a turbine. The nitrogen-enriched air 18 that is left after oxygen separation from air is removed at the inlet of the combustor. The nitrogen which is at high pressure is used to drive a turbine for power production as those of skill in the art will appreciate. The output work of this turbine compensates for the work required for compression of the oxygen-enriched air and is expected to improve overall system efficiency. [0024] The importance of the polymer membrane 10 is to produce high partial pressure on the outer surface of the ITM thereby achieving high O 2 flux through the ITM membrane. The compression of oxygen-enriched air consumes less power in comparison to a similar case of an ITM using air. Thus, the pumping work required for the compression of air at the inlet of the polymer membrane 10 and the oxygen-enriched air (having small volume due to the absence of most of the nitrogen) is expected to be reduced. [0025] Two possible arrangements of the polymer membrane 10 and the ceramic membrane 12 are disclosed herein. In the first arrangement as shown in FIG. 3 , the O 2 -enriched air is produced in the polymer membrane 10 and is then utilized in the oxygen transport membrane 12 (a type of series action). It is also preferred to combine both the polymer membrane 10 and the ion transport membrane 12 to provide onsite separation and combustion as shown in FIG. 4 . [0026] Utilizing oxygen-enriched air in the ceramic membranes 12 results in a reduced pressure drop in these membranes. See Table 1. The reduction in pressure drop leads to less variation in pressure along the membranes and ensures high stability of the ceramic membranes 12 . Utilizing oxygen-enriched air in the ceramic membranes 12 results in reduced volume/surface of the ceramic membranes and reduces the volume requiring high temperature levels. This also leads to a significantly lower cost of the air separation unit. This result is attributed to the significant reduction in volume and the low material cost per productivity for the polymer membranes 12 . [0000] TABLE 1 Improvements due to hybrid polymer ceramic membrane % Reduction % Reduction in % Point Increase System Considered in Volume Pressure Drop in Efficiency Base Counter-Current 70.8% 68.6% — Separation-Only [11] Base Co-Current 46.0% 45.0% — Reactive [11] MCRI [13] 22.7% — — AZEP100H [12] 54.5% 36.0% 1.10% AZEP100 [12] 64.7% 62.0% 0.20% EXAMPLE [0027] It is well-known that the flux of oxygen through a ceramic membrane at a given temperature increases with increasing partial pressure difference of oxygen across the membrane (chemical potential difference). To quantify the effect for the ceramic membranes, of interest, experiments and numerical calculations were conducted varying the partial pressure of oxygen in the feed side on the oxygen flux permeation across the membrane. The oxygen permeation flux was measured with the setup shown in FIG. 5 . [0028] Borosilicate glass rings, whose inner diameter were 13 and 16 mm, were used as the sealant to seal the sample between dense alumina tubes. Silver paste was painted on the area where the sample membrane may contact with borosilicate glass rings to prevent the membrane from reacting with the borosilicate glass. Additionally 1 μm Ag film was sputtered with RF sputtering on the surface of both sides of the membrane as shown in FIG. 6 . The Ag film agglomerates into isolated islands after the permeation measurements, which is confirmed by SEM image in FIG. 7 . The oxygen permeation flux measurement was performed between 550 and 700° C. The gas mixture of oxygen and argon was introduced into the upper chamber (feed side) as the feed gas, while helium was fed to the lower chamber (permeate side) as the sweep gas. The total inlet gas flow rate on the feed side was fixed at 100 ml min −1 and the permeate side was 30 ml min −1 . The flow rates were controlled by mass flow controllers (MKS instruments Inc., Model M100B). The gas exiting from the permeate side was analyzed with a gas chromatograph (Agilent Technology, 3000A micro GC) equipped with a 30 m molecular sieve column and a TCD detector. Helium gas was used as the carrier gas. Leakages from pores in membranes and connection between borosilicate glass and membranes were checked with the concentration of argon gas at the permeate side. Also, leakage from connection between borosilicate glass and alumina tubes was checked with the concentration of nitrogen gas at the permeate side. No leakage was detected during measurements. [0029] The oxygen permeation flux J O2 is then calculated as follows [0000] J O2 =c O2 F/S [0000] in which c O2 is the oxygen concentration at the permeate side detected by the gas chromatograph, F the flow rate of the sweep gas and S the area of the membrane. The experimental data were fitted to the equation [0000] J O2 =A exp (− B/T ) [( P O2 ′) n −( P O2 ″) n ] [0000] with A, B and n being the parameters for fitting, P O2 ′ and P O2 ″ the oxygen partial pressure at the feed and permeate sides. The fitting was performed via minimizing the least square error between measurements and model prediction using a global optimization solver (BARON) which ensures that the best possible fit is obtained. Most data points are matched very accurately with maximal discrepancy between model and experiment in the order of 20%. [0030] The oxygen permeation fluxes were found to increase with increasing PO2 (having a PO2 dependence of 0.4) for a range of temperature, as shown in FIG. 8 . Additionally, fitting was performed using only A and B as adjustable parameters and fixing n=0.5; the model-experiment discrepancy is slightly higher, but the fit is again very good. This observation suggests that the oxygen permeation flux is limited by the surface oxygen exchange kinetics for the feed side. In addition, the oxygen permeation fluxes obtained experimentally from 550 to 700° C. have similar activation energies in this temperature range. [0031] FIG. 9 quantifies the enhancement of the oxygen permeation as a result of the rise in the oxygen concentration in the feed side considering the ITM reactor on its own. Additionally, preliminary system level simulations for oxy-fuel power cycles with ITM were performed using a semi-detailed ITM model [10-11]. The cycles consider both separation-only ITMs as well as reactive systems, including novel proposals [12-13]. To quantify the potential of the hybrid ceramic/polymeric system, pre-enriched air (80% O 2 , 20% N 2 by mol) was used. Two caveats should be noticed, namely i) the simulation does not consider the penalty and volume associated with the polymeric membrane and ii) the kinetic model used for the ITM [10-11] was fitted to data that did not include high partial pressures of oxygen. In comparison to the base case (79% N 2 , 21% O 2 by mol), the results (Table 1) of O 2 pre-enriched air (80% O 2 and 20% N 2 ) indicate a noticeable decrease in pressure drop and a significant decrease in surface area/volume required for the ceramic membrane. This indicates a potential to reduce the capital cost substantially. Moreover, the results indicate a slight increase in efficiency. [0032] The combustor disclosed herein can be used in real gas turbine engines ( FIG. 10 ) to replace the conventional fuel air combustor, thus, the proposed gas turbine combustion chamber consists of a number of combustors distributed on the perimeter outside the compressor-turbine shaft as in the conventional gas turbine unit. The technology is also suitable for other fossil fuel combustors such as fire and water tube boilers. [0033] The focus of this disclosure is integrated separation and combustion; however, the invention of combining polymeric and ceramic membranes can be used also for separation of oxygen from air without reaction in a combustor. [0034] The numbers in brackets refer to the references listed herein the contents of which are incorporated herein by reference. [0035] It is recognized that modifications and variations of the invention disclosed herein will be apparent to those of ordinary skill in the art and it is intended that all such modifications and variations be included within the scope of the appended claims. References [0036] [1] Scott-Coombe, H. and Nieh, S., 2007, Polymer membrane air separation performance for portable oxygen enriched combustion applications, Energy Conversion and Management, Vol. 48, pp. 1499-1505. [0037] [2] Bernardo, P., Drioli, E. and Golemme, G., 2009, Membrane gas Separation: A review/state of the Art, Ind. Eng. Chem, Res., Vol. 48, pp. 4638-4663. [0038] [3] Phair, J. W. and Badwal, S. P. S., 2006, Materials for separation membranes in hydrogen and oxygen production and future power generation, Science and Technology of Advanced Materials, Vol. 7, pp. 792-805. [0039] [4] Tan, X., Li, K., Thursfield, A., and Metcalfe, I. S., 2008, Oxyfuel combustion using a catalytic ceramic membrane reactor, Catalysis Today 131, 292-304. [0040] [5] World oil, ceramic membranes for produced water treatment, Vol. 230, No. 4, April 2009. [0041] [6] Ericsson, S., 2005, Development of methane oxidation catalysts for different gas turbine combustor concepts, Ph. D. Thesis, The Royal Institute of Technology, Stockholm, Sweden. [0042] [7] Kvamsdal, H. M., 2005. Power generation with CO 2 management our activities, Gas Technology Center, NTNU-SINTEF. [0043] [8] Wall, T. F., 2007, Combustion processes for carbon capture, Proceedings of the Combustion Institute 31 (2007) 31-47. [0044] [9] Buhre, B. J. P., Elliott, L. K., Sheng, C. D., Gupta, R. P. and Wall, T. F., 2005, Oxy-fuel combustion technology for coal-fired power generation, Progress in Energy and Combustion Science 31, 283-307. [0045] [10] Mancini, N. D. and Mitsos, A. Ion Transport Membranes for Oxy-combustion Power Cycle Applications: I Intermediate Fidelity Modeling. Energy, (2011), 36(8):4701-4720, 2011. [0046] [11] Mancini, N. D. and Mitsos, A. Ion Transport Membranes for Oxy-combustion Power Cycle Applications: Analysis & Comparison of Alternatives, Energy, 36(8):4721-4739, 2011. [0047] [12] Mancini N. D. and Mitsos, Conceptual Design and Analysis of ITM Oxy-combustion Power Cycles, Physical Chemistry Chemical Physics, 13:21351-21361, 2011. [0048] [13] Mancini, N. D. and Mitsos, A Multiple Compartment Ion Transport Membrane Reactive Oxygen Separator, Submitted: Industrial & Engineering Chemistry Research
Integrated polymeric-ceramic membrane-based oxy-fuel combustor. The combustor includes a polymer membrane structure for receiving air at an input and for delivering oxygen-enriched air at an outlet. An oxygen transport reactor including a ceramic ion transport membrane receives the oxygen-enriched air from the polymer membrane structure to generate oxygen for combustion with a fuel introduced into the oxygen transport reactor.
8
BACKGROUND OF THE INVENTION The present invention relates to the generation of ions, and more particularly to the generation of ions with increased output currents over a prolonged period. Ions can be generated in a wide variety of ways. Common techniques include the use of air gap breakdown, corona discharges, and spark discharges. Other techniques employ triboelectricity, radiation (alpha, beta, and gamma as well as x-rays and ultraviolet light), and microwave breakdown. When utilized for the formation of latent electrostatic image, all of the above techniques suffer certain limitations in ion output currents and charge image integrity. A further approach which offers significant improvement in this regard is described in U.S. Pat. No. 4,155,093 and the improvement patent U.S. Pat. No. 4,160,257. These patents disclose method and apparatus for ion generating involving what the inventors term "glow discharge". This is accomplished through the application of a high voltage time-varying potential between two electrodes separated by a solid dielectric member. As disclosed in U.S. Pat. No. 4,155,093, the varying potential causes the formation of a pool of positive and negative ions in an air region adjacent an edge surface of one of the electrodes, which ions may be extracted to form a latent electrostatic image. U.S. Pat. No. 4,160,257 discloses the use of an additional electrode to screen the extraction of ions, providing an electrostatic lensing action and preventing accidental image erasure. In the preferred embodiment of the ion generation apparatus discussed above, the solid dielectic member comprises a sheet of mica. An advantageous method for fabricating such devices is disclosed in U.S. Pat. No. 4,381,327. A mica sheet is bonded to metal foils using pressure sensitive adhesive, and the metal foils etched in a desired electrode pattern. This fabrication provides excellent ion output currents and reasonable service life. Such devices, however, are commonly exposed to atmospheric environmental substances and byproducts of the ion generation process, which contributes to corrosion thereof. This apparatus also suffers the tendency to accumulate contaminants at the ion generation sites. Such contaminant buildup and corrosion seriously reduce the service life of these devices. Accordingly, it is a primary object of the invention to provide improved ion generation using a glow discharge ion generator. A related object is to achieve a method which is compatible with a glow discharge ion generator incorporating a mica dielectric. Another object of the invention is to attain enhanced ion current outputs. A related object is the formation of latent electrostatic images at higher speeds and with lower drive voltage requirements. A further object of the invention is the achievement of prolonged service life in ion generators of the glow discharge type. A related object is the reduction of contaminant buildup during ion generation. Yet another related object is diminished corrosion of such devices. SUMMARY OF THE INVENTION In fulfilling the above and additional objects of the invention, an ion generator of the glow discharge type is subjected to extrinsic heating to provide increased ion currents with improved image integrity. An ion generator consisting of a plurality of electrodes at opposite sides of a solid dielectric is subjected to high voltage varying potentials in order to create glow discharges, while simultaneously heating the device to a prescribed temperature. In the preferred embodiment, the solid dielectric member is comprised of mica. In accordance with one aspect of the invention, the glow discharge device is heated during the operation of the device. The device is preferably pretreated by operation at an elevated temperature prior to regular operation of the device. The ion generator may be heated over an extended period to provide continuing improvements in ion current output and service life. Another aspect of the invention is seen in the regulation of the elevated temperature in order to provide a calibrated heating of the ion generator. In the preferred embodiment, the glow discharge device is heated to a temperature in the range 130° F.-270° F., most advantageously around 150° F. The use of elevated temperatures in the operation of glow discharge devices has been observed to lead to significantly higher output currents, even when the external heat source is subsequently removed. This technique also achieves marked reductions in contaminant buildup, and in the formation of corrosive substances adjacent the glow discharge device. BRIEF DESCRIPTION OF THE DRAWINGS The above and additional aspects of the invention are illustrated in the detailed description of the invention which follows, taken in conjunction with the drawings in which: FIG. 1 is a sectional schematic view of extrinsically heated ion generation apparatus in accordance with the preferred embodiment; FIG. 2 is a cutaway perspective view of a dot matrix imaging device of the type illustrated in FIG. 1; and FIG. 3 is a plot of ion current output as a function of operating time for ion generators of the type shown in FIG. 2. DETAILED DESCRIPTION In the preferred embodiment of the invention, ion generation apparatus of the type disclosed in U.S. Pat. No. 4,160,257 is modified by the incorporation of thermal control apparatus. During the normal operation of the apparatus disclosed in this patent, such devices generate internal heat due to the imposition of high voltage, high frequency alternating potentials between electrodes on opposite sides of a solid dielectric. With typical operating parameters such as those described below in Example 2, the ion generator will be naturally heated to a temperature on the order of 120° F. In the ion generating method of the invention, this heating effect is supplemented by exposing the ion generator to an additional heat source. Advantageously, the ion generator is heated to a temperature in the range 130° F.-270° F., most preferably around 150° F. To be effective in accomplishing the advantages discussed below, such heating should be effected during the generation of glow discharges through the use of high voltage time-varying potentials. FIG. 1 shows in section an illustrative ion generator 10 of the type disclosed in U.S. Pat. No. 4,160,257, including thermal control apparatus in accordance with the present invention. The ion generator 10 includes a driver electrode 12 and a control electrode 13, separated by a solid dielectric layer 11. The preferred dielectric material is mica, which may be fabricated in sufficiently thin films to avoid undue demands on the driving electronics, and which is less vulnerable to deterioration due to byproducts of the ion generation process. Especially preferred is Muscovite mica, H 2 KAl 3 (SiO 4 ) 3 . A source 15 of alternating potential between electrodes 12 and 13 induces an air gap breakdown in the aperture 14, generating a pool of ions of both polarities. A third, screen electrode 17 is separated from the control electrode by a second dielectric layer 16. Advantageously, the second dielectric layer 16 defines an air space 18 which is substantially larger than the aperture 14 in the control electrode. This is necessary to avoid wall charging effects. The screen electrode 17 contains an aperture 19 which is at least partially positioned under the aperture 14. Ions are extracted from the air gap breakdown in aperture 14 using the control potential V C to control electrode 13. A screen potential V S is applied to screen electrode 17 to regulate this extraction of ions. Optionally, the ion generator 10 further includes a mounting block 20 adjacent the driver electrode 12 to control heat buildup in ion generator 10. In the illustrated embodiment, the mounting block 20 consists of a metal such as aluminum or stainless steel with a flat mounting surface. In this instance, the ion generator laminate 10 further includes a thin, electrically insulative layer 21 to electrically isolate the driver electrode 12 from mounting block 20. The ion generator 10 incorporates an electric heater 40 in order to heat the various structures. This heating may be controlled through the use of a thermocouple 30, which monitors local temperature variances and acts as a thermostat for heater 40. It is not essential, however, to monitor temperatures when utilizing a reasonably accurate heating element 40. In the illustrated embodiment, the electric heater 40 is placed adjacent mounting block 20, and transmits heat to the core structures through this block and through electrically insulative layer 21. This placement may be modified for convenience of construction; the power requirements of heater 40 will depend on its location. The heater may even be located in a separate structure, with a thermally conductive connection to generator 10. As depicted in FIG. 1, the thermocouple 30 is appended to control electrode 13. This location provides precise monitoring of the pertinent temperature. The positioning of thermocouple 30 may be modified for engineering convenience, with some sacrifice in accuracy if this device is remote from the ion generation sites. In a preferred version of the ion generating apparatus 10, such apparatus is configured as a multiplexible dot matrix imaging device 10' as shown in the cutaway view of FIG. 2. The ion generator 10' comprises a series of finger electrodes 13 and a cross series of selector bars 12 with an intervening dielectric layer 11. Ions are generated at apertures 14 in the finger electrodes at matrix crossover points; the extraction of these ions is controlled by screen electrode 17 with screen apertures 19. The ion generator 10' is mounted to metallic block 20. The imaging device 10' of FIG. 2 is advantageously incorporated in an electrostatic transfer printer of the type disclosed in U.S. Pat. No. 4,267,556. Ions extracted from the apertures 14 are screened through apertures 19 to form an electrostatic image on the dielectric surface of an imaging cylinder. The ion generating apparatus 10 provides a number of significant advantages over the prior art. The primary advantage is that of a marked increase in ion output currents; typically, these currents increase by a factor of 2-3 or more. This effect is enhanced by the continued operation of the apparatus at elevated temperatures. Such increases occur after a period of operation at elevated temperatures even when the temperature is later reduced; i.e. the output current will be significantly higher than that encountered in apparatus continually operated at the reduced temperature. See Example 2. For best results, the ion generator of the invention is pretreated by operation at elevated temperatures for a period. The increased output currents attributable to the invention allow the use of lower driving voltages, and permit significant improvements in the speed of operation of electrostatic imaging devices embodying the invention, such as apparatus of the type disclosed in U.S. Pat. No. 4,267,556. A second result of this technique is an inhibited formation of contaminant substances at or near the ion generation sites. Prominent among these substances is ammonium nitrate, which tends to form as imperfect white crystals. With further reference to FIG. 1, in ion generator 10, contaminants will tend to accumulate in and around control aperture 14 and screen aperture 19. In the case of dot matrix apparatus such as that shown in FIG. 2, the contaminant formation if unchecked will cause spurious dots in the electrostatic image, as well as nonuniformities in the image. In the embodiment in which such an ion generator is used to form a latent electrostatic image on a contiguous dielectric imaging member, as in U.S. Pat. No. 4,267,556, there is the additional danger of contaminent buildup on the imaging member. In such instances, it may be advisable to include additional heaters adjacent the dielectric imaging member. A third characteristic of the invention is a significant reduction in the incidence of corrosive substances formed during the ion generation process. Such substances typically include nitric acid and oxalic acid. The invention is further illustrated in the following nonlimiting examples: EXAMPLE 1 An ion generator 10' as illustrated in FIG. 2 was fabricated as follows: a sheet of mica having a thickness of about 25 microns was cleaned using lint-free tissues and methyl ethyl ketone (MEK). After drying, the mica sheet was suspended from a dipping fixture and lowered into a bath of pressure sensitive adhesive consisting of a silicon-based pressure adhesive formulation until all but two millimeters was submerged. The mica was then withdrawn from the adhesive bath at the speed of two centimeters per minute, providing a layer of adhesive approximately three microns in thickness. The coated mica was stored in a dust-free jar and placed in a 150° C. oven for five minutes in order to cure the pressure sensitive adhesive. Two sheets of stainless steel 25 microns thick were cut to the desired dimensions and cleaned using MEK and lint-free tissues. One of the sheets was placed in a registration fixture, followed by the coated mica and the second foil sheet. Bonding was effected by application of light finger pressure from the middle out to the edges, followed by moderate pressure using a rubber roller. Any adhesive remaining on exposed mica surfaces was removed using MEK and lint-free tissues. The edges of the lamination were then covered with a 0.6 millimeter coated Kapton tape coated with the pressure sensitive adhesive formulation. The foil layers were respectively etched in the patterns of electrodes 12 and 13 (FIG. 2) using a positive photoresist. The laminate was returned to the registration fixture, which was then placed in a screen printer having a pattern corresponding to finger electrodes 13 of FIG. 2. The screen printer was employed to create a pattern of glass dielectric spacers 16. A continuous stainless steel foil 17 was then inserted in the registration fixture and its apertures 19 aligned with the apertures 14 using a microscope. The laminate was then set aside for a number of hours to cure. A thermocouple was mounted to screen electrode 17 with pressure sensitive tape. The laminate was inverted, and a 100 micron layer of G-10 engineering thermoplastic applied to its drive electrode face. This structure was in turn bonded to an aluminum mounting block using pressure sensitive adhesive. A 100 watt heating plate 40 was affixed to the aluminum mounting block. The thermocouple monitored temperatures of the active region of the head to regulate the operation of heating plate 40. EXAMPLE 2 An ion generator was constructed as described in Example 1. The complete print head consisted of an array of 16 drive lines 12 and 96 control electrodes 13 which formed a total of 1536 crossover locations. Corresponding to each crossover location was a 0.006" etched hole in the screen electrode. Bias potentials of the various electrodes were as follows: ______________________________________Screen Potential V.sub.S -600 voltsControl Electrode Potential V.sub.C -300 volts(during the application of a -400 volt extraction pulse thisvoltage becomes -700 volts)Driver Electrode Bias +300 voltswith respect to screen potential______________________________________ The DC extraction voltage was supplied by a pulse generator with a print pulse duration of 10 microseconds. Charge image formation occured only when there was simultaneously a pulse of -400 volts to the finger electrodes 13, and an alternating potential of two kilovolts peak-to-peak at a frequency of 1 MHz supplied by the finger electrodes 13 and drive lines 12. The ion generation was maintained at a spacing of 8 mils from a dielectric cylinder in apparatus of the type disclosed in U.S. Pat. No. 4,267,556. Heaters were installed adjacent the dielectric cylinder to maintain the cylinder at 105° C. This printer was run over an extended period, while monitoring the ion current to the screen electrode 17. Periodically, developed print samples produced by this printing apparatus were examined for image integrity. FIG. 3 gives a plot of the current measured at the screen electrode over time. Curve 100 represents the values measured for an ion generator heated to 150° F. Curve 110 represents the values measured for an ion generator heated to 140° F. In the latter case, the temperature was briefly reduced to 120° F. at around 90 hours, at which point the current fell to 450 microamperes. For purposes of comparison, curve 120 represents values measured for an ion generator with no extrinsic heating. Print samples produced by the ion generator heated to 140° F. and 150° F. remained uniform with clean background at 100 hours. It was observed that acceptable print quality was achieved even when lowering the control voltage to -250 volt pulses. Print samples produced from the unheated ion generator showed weak and missing dots, and background streaks. EXAMPLE 3 An ion generator was constructed as described in Example 1. The ion generator was placed for 1 hour in an oven heated to 212° F., with no potentials applied. The print quality and ion current were compared before and after heating and were virtually unaffected. While various aspects of the invention have been set forth by the drawings and the specification, it is to be understood that the foregoing detailed description is for illustration only and that various changes in parts, as well as the substitution of equivalent constituents for those shown and described, may be made without departing from the spirit and scope of the invention as set forth in the appended claims.
Method and apparatus for ion generation with enhanced performance through operation at elevation temperatures. A glow discharge ion generator is subjected to extrinsic heating, both preliminarily and during continued operation, thereby providing increased ion current outputs. Such thermal control additionally prolongs the life of the ion generator by reducing corrosion and contaminant buildup.
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CROSS-REFERENCE TO RELATED APPLICATIONS This application is a Continuation-In-Part of U.S. application Ser. No. 13/108,541 filed May 16, 2011, which issued as U.S. Pat. No. 8,336,787 on Dec. 25, 2012, which is a Continuation of U.S. application Ser. No. 11/842,567 filed Aug. 21, 2007, which issued as U.S. Pat. No. 7,975,928 on Jul. 12, 2011, which claims priority to U.S. Provisional Application No. 60/897,278 filed Jan. 25, 2007 and U.S. Provisional Application No. 60/839,331 filed Aug. 22, 2006. All recited applications are incorporated herein by reference in their entirety and priority is claimed under all these applications. TECHNICAL FIELD The invention relates generally to a method for supplementing the information available in a print medium by providing access to multi-media. More particularly, the invention relates to a system which uses color coded zones in a printed surface to provide a portal to sound, video, web-based or other media. Even more particularly, the invention relates to the use of a system employing both invisible and visible printed inks and specific wavelengths of light to activate sound signals, video, and/or web-based media. BACKGROUND OF THE INVENTION Most printed surfaces are silent and static, i.e., they do not emit sounds or display visual information relating to the objects depicted on the surface. Examples of such surfaces include the pages of books, magazines, newspapers, board games and displays. Audiotapes, compact discs and other media can provide an audible version of the content of books. Computer systems and programs are known to provide that content on a display. Some computer programs highlight words as they are read as well as provide an audio version of the content being highlighted. Other computer systems and programs allow a user to click on a word or image to provide additional audio and visual information relating to the content. These conventional systems, however, are not part of the actual print medium and they lack the look and feel of the print medium. Conventional systems also exist that use a scanner or stylus to scan a printed surface imprinted with a conventional two dimensional proprietary pattern (i.e. bar code) or applied medallion. These systems, however, are not ideal for printed surfaces because they involve distracting or unattractive extraneous indicia imprinted in the printed surface. Systems that employ optical readers or other types of detectors to detect images, symbols, and barcodes in printed materials are disclosed in U.S. Pat. No. 6,722,569. The '569 patent discloses an optical reader that determines whether a captured image on printed material is a color or photographic image or a symbol. U.S. Pat. No. 6,375,075 discloses a symbol image sensor that includes one or more filters which remove or reduce certain wavelengths of light reflected from the symbol to create color separations at the image sensor. In the '075 patent, a comparator, such as a microprocessor, programmed general purpose computer, or digital logic circuit can determine the position and color of the various elements of the symbol based on the decoded image data produced by the sensor. Systems have also been developed in which sound data have been encoded into a printed surface and can be extracted using readers that decode the encoded information. It is sometimes desirable to encode data, including sound data, onto a reflective print having an image, symbol or barcode. The sound data, which may be optically readable, provides information relating to the image. The sound data may be encoded onto the print so that it overlays the image, or alternatively, is encoded in a margin surrounding the image on the print. A reader is typically provided which reads the encoded data and emits sound corresponding to that data. U.S. Pat. No. 5,502,304 discloses systems wherein sound data is imprinted in the form of a machine readable code, such as a barcode, onto a still form reflection print, or, invisible ink is used to form a scanable barcode encoding sound information. U.S. Pat. No. 6,561,429 discloses an adjustable reader and a method of reading encoded indicia on an object. The reader includes a detector for detecting the indicia and an emitter coupled to the detector for emitting a signal encoded by the indicia. The indicia of the prior art, which can be a sound indicia is formed out of an invisible dye. The sound indicia of the prior art is preferably a dye having special absorption in the infrared region or ultraviolet region of the radiation spectrum. Such a dye is selected so that the dye does not absorb or fluoresce light in the human visible spectrum, but which is visible to optical reading devices capable of illuminating the indicia with infrared or ultraviolet light. For this purpose, the dye of the prior art may be 4,4″-bis(triazin-2-ylamino)stilbene-2,2′-disulfonic acids; 2-(stilben-4-y)naphthotriasoles; or 2-(4-phenylstelben-4-yl)benzoxazoles, or other suitable dye. Other systems which use detectors to detect and trigger the expression of encoded multimedia content, including sounds, from printed material include those disclosed in U.S. Pat. No. 6,556,690. The '690 patent discloses a system where data is encoded in an image field on a photographic print and can be reproduced as sound information. U.S. Pat. No. 6,094,279 discloses a system and process that uses infrared dyes to integrate data, in a visually imperceptible form, into a printed color image. This system allows for encoding of voice or sound data into a still print and uses an optical reader. Still other systems employ areas called “active colors” on the print. Active colors are colored areas that can be recognized by a detector and decoded. U.S. Pat. No. 5,869,828 discloses a color coding system for encoding information on products and other substrates where the color code is printed using single intensity colors in specific shapes that can be easily read. U.S. Pat. No. 6,141,441 discloses a technique for decoding message data that has been encoded into a printed color image made up of small color regions called signal cells that carry the encoded message. Printed surfaces can provide more valuable sources of information if the images can be expressed in audio, visual or other form in addition to the static image on the surface. For example, children and adults who are learning how to read could benefit from books and other print media that provide information relating to the visual images in sound and/or video form. Users who are visually impaired or have a learning disability could similarly benefit from such a system. Readers who are trying to learn a foreign language could benefit from a system that provides audio output of the print content. The art has heretofore not provided systems which can express the visual content of the printed medium in audio, video or web-based form. A simple yet comprehensive and unobtrusive system is needed for providing audio, visual and/or other expressions corresponding to the print content. OBJECTS OF THE INVENTION It is a primary object of the present invention to provide a surface having visible images thereon with indicia coding for an output presentation in audio, visual or other media format and means for reading those indicia to trigger the presentations. It is a related object of the invention to provide a user-friendly, educational or entertainment tool employing light as a means of triggering an audio presentation, web-based streaming video or flash media presentation, or other media presentations from a printed surface to enhance the educational or entertainment value thereof. It is a further object of the invention to provide a simple, user-friendly system for detecting and triggering media presentation in audio, web-based streaming video, or flash media format using a portable handheld device to trigger discrete coded zones encoded in different portions of the surface. SUMMARY OF THE INVENTION The present invention provides a media asset system which comprises a surface containing a discrete coded zone within a visual image corresponding to a predetermined output presentation; a handheld reader with a sensor enabled to detect the discrete coded zone, wherein the reader is capable of producing an output signal corresponding to the discrete coded zone; and an audio output device for presenting the output signal corresponding to the discrete coded zone. In another embodiment, the system further comprises a video output device for presenting the predetermined output presentation. In a preferred embodiment, the sensor is enabled to receive a light signal from a source, and the system further comprises a memory having a plurality of files, a processor in communication with the sensor, the memory, and the output device, wherein the processor selects from the plurality of files, where a file corresponds to a discrete coded zone and initiates some predetermined output presentation as prescribed by the file. Preferably this source contains the discrete coded zone. It is further preferred that the sensor is enclosed within a sensor housing configured to displace the sensor from the surface so that the sensor effectively reads light from the surface and curtains off extraneous light. Preferably, the sensor housing comprises an opening of sufficient size to read the discrete coded zone. This system further comprises an outer sensing around the sensor housing. This outer housing is preferably transparent. One or more light sources may be located in a space between the sensor housing and outer housing. The memory may be removable from the system. The discrete coded zone is preferred to be substantially imperceptible to the human eye. The discrete coded zone may contain a substance that is essentially invisible to the human eye, and becomes additionally perceptible by the sensor when illuminated by one or more wavelengths of light. In another embodiment, the handheld reader and audio output device are encompassed in a housing. The audio output device may be external to the handheld reader. The system may further comprise a charger cradle or cable for recharging the handheld reader. The system may also comprise a download cradle or cable configured to download files for the handheld reader. In another embodiment, the discrete coded zone corresponds to an internet address, and the handheld reader is capable of sending to a receiver a wireless signal containing data enabling the internet address to be accessed and the predetermined output presentation to be presented. Alternatively, the discrete coded zone may contain textual words or images and the predetermined output presentation corresponds to the textual words or images. The present invention also provides a media asset method for presenting a predetermined output presentation comprising the steps of directing a beam of light at a discrete coded zone, causing the discrete coded zone to become additionally perceptible to a sensor of a handheld reader; detecting the discrete coded zone using the sensor; selecting a predetermined output presentation corresponding to the discrete coded zone, wherein the predetermined output presentation is stored in a memory; and presenting the predetermined output presentation through an audio output device in response to the handheld reader's detection of the discrete coded zone. This method may further comprise the step of presenting the predetermined output presentation through a video output device in response to the detection of the discrete coded zone. The discrete coded zone may also contain textual words or images and the predetermined output presentation corresponds to the textual words or said images. Furthermore, the invention presents a surface including one or more visible images and one or more discrete coded zones corresponding to a particular medium of expression, wherein one or more discrete coded zones are capable of reflecting light within the visible spectrum in response to a beam of light directed by a handheld reader, and one or more of the discrete coded zones are within one or more of the visual images. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1A is a printed page of a children's book using the present invention depicting visual information and discrete coded zones encoding for an audio presentation. FIG. 1B depicts a visually colored circle from the printed page surrounding a discrete coded zone. FIG. 1C depicts a close-up of a hinged flap from the printed page of a children's book using the present invention. FIG. 2A is an exploded view of a handheld, flashlight-type reader of the present invention, for use in triggering output presentations from discrete coded zones on the printed page. FIG. 2B is an assembled view of the same handheld flashlight-type reader. FIGS. 3A-F show a further embodiment of the handheld reader depicting a stylus detector for use in triggering an output presentation from a discrete coded zone within a visual image on the printed page. FIG. 3A is partial view of the handheld reader, showing only the top portion. FIGS. 3B-F show the whole handheld reader in an isometric view, front view, side view, bottom view, and top view, respectively. FIG. 4 is an exploded view of a download station of the present invention, used in downloading files to the handheld reader of the present invention with a computer. The subject matter which is regarded as the invention is particularly pointed out and distinctly claimed in the concluding portion of the specification. The aforementioned figures share constituent elements with other figures. Therefore, shared constituent elements will be referred to using the same reference numerals, and an explanation thereof will be omitted. The invention, however, both as to organization and method of practice, together with the further objects and advantages thereof, may best be understood by reference to the following description taken in connection with the accompanying drawings in which: DETAILED DESCRIPTION The present invention is a system for activating audio, web-based streaming video, flash animation or other media presentations from a visible surface, e.g., a printed surface. The surface includes one or more visible images and one or more discrete coded zones which encode for a particular audio, video or other media presentation. As used herein the term “visual surface” may include any surface which includes one or more visual representations. Visual surfaces include, without limitation, the pages of print media, game boards, packaging, signs, exhibits or three-dimensional objects. In an alternative embodiment of the invention, the printed surface contains a plurality of visual images and includes one or more discrete coded zones which encode for a particular sound. Each of those zones are surrounded by or overlaid with an essentially invisible substance, e.g., an invisible ink, which becomes additionally perceptible when light is shone upon it. The ink is invisible to the user but can be detected when light of a certain wavelength causes it to fluoresce and the fluorescent light is detected. The system includes a handheld reader for triggering the presentation which comprises a light source and a sensor for detecting light reflected from one or more discrete coded zones which code for the presentation. One preferred embodiment of this system includes a sound player which plays a sound when light is reflected from a discrete coded zone and is detected by the sensor. In an alternative embodiment of this system, the reader detects a discrete coded zone in the printed surface that corresponds to an internet address. The handheld reader sends a wireless signal to a receiver, such as a computer, to access a predetermined output presentation, such as a particular webpage, flash media, or streaming video content. In addition to flash media, the system can employ various types of web based media, including, but not limited to, HTML, XML, databases, JAVA and JAVA applets, Flash and other vector based graphics, rastor graphics, audio, image types including .jpeg and .gif image types, video, documents including .doc and .pdf document types, and hypertext markup languages. The handheld reader may comprise a flashlight-like reader capable of directing a first beam of violet light, followed by a second beam of white light, within the visible spectrum. The first beam serves to determine whether or not invisible ink is present on the printed surface. In a preferred embodiment, the first beam generates violet light of 405 nm which causes the invisible ink to fluoresce and that fluorescent light is detected. The second beam serves to establish the color value of the visible ink printed on the surface. While described for convenience as a “flashlight,” the reader of the invention includes any convenient, handheld housing which contains the several components of the triggering device. The handheld reader includes a light sensor for detecting light of different wavelengths within the visible spectrum. A light sensor functions like a color measuring chip, as it detects light fluorescing from the invisible ink when that ink is contacted by the beam on the violet edge of the visible spectrum and it detects light within the visible spectrum reflected from the discrete coded zones. The handheld reader includes a switch activated by the light sensor when light is detected. If invisible ink is detected on the surface to be measured, a switch activates a processor which causes the flashlight to emit the second beam of white light. When visible light reflected from the colored zone is detected, a sound player is activated which plays a particular audible message encoded in the discrete coded zone. An inner, opaque, sensor housing curtains off ambient light and contains the light sensor and sources of light. The sensor housing desirably makes even contact with the surface of the printed medium. An outer housing is positioned around the sensor housing to permit the flashlight to be centered on a discrete coded zone. The outer housing desirably has a circumference such that both the visual image and the discrete coded zone, if any, are encompassed by the outer housing. This arrangement shields the sensor from outside light and avoids a variation or fluctuation in color measurement by the sensor. The forward part of the flashlight has a first light emitting diode for emitting a first beam of violet light, a second light emitting diode for emitting a second beam of white light and a light detector for detecting wavelengths of light reflected from the discrete coded zone. The forward part of the flashlight comprises an inner, sensor housing surrounding the first light emitting diode, the second light emitting diode and the light detector. The length of the sensor housing is set to space the light detector at a predetermined distance from the discrete coded zones so that it can accurately measure light reflected from those zones. Desirably the configuration of the opening of the housing matches that of the discrete coded zone so the light detector can detect essentially all of the light reflected by the discrete coded zone at which it is directed. The forward part of the flashlight has an outer housing circumferentially surrounding the sensor housing. The diameter of the outer housing is set so that the outer cone, and the flashlight itself, can be centered on, i.e. registered on a visual image and so that the visual image and the discrete coded zone contained within that image, if any, are both encompassed by the outer housing. In a preferred embodiment of the invention, the outer housing may be transparent. This will permit the user to view a message, such as a printed word, written with invisible ink within the coded zone. The user can then see and read the information displayed between the inside of the transparent outer housing and the outer edge of the opaque sensor housing. To illuminate these otherwise invisible characters, the forward part of the flashlight may have third and fourth light emitting diodes which emit violet light. These are located between the inner sensor housing and the outer housing. The central part of the flashlight houses a first switch activated by a user. The first switch activates the first or the first, third and fourth light emitting diodes. The sensor housing has a second switch activated by the sensor when light emanates from the invisible ink and is detected. The switch causes the second light emitting diode to emit white light. The back part of the flashlight has a speaker which plays a sound coded for by the discrete coded zone when light of a particular wavelength reflected from the discrete coded zone is detected. FIG. 1A depicts a page of a book for children. The page shown is printed with several images and several colored circles. The colored circles encode sounds associated with the images. These sounds are triggered by the triggering device. Page 100 includes an image of a truck or other artwork 102 , text 110 and visible colored circles 104 printed by a traditional four color (CMYK) process. FIG. 1B depicts a colored circle 104 surrounding an annular invisible zone 106 which is printed with invisible ink. A hinged flap 108 is also present, as shown in FIG. 1C . When the invisible ink is detected, the system for detecting and triggering a sound from visible circle 104 is activated. A hidden word may be printed in invisible ink within the annular invisible zone 106 . As shown in FIG. 1C , it contains the printed word “ENGINE”. The visual images containing the discrete coded zones may be in irregular shapes rather than circles, rectangles or ellipses. All colored zones are identified as either active or inactive by the presence of absence of the invisible ink. The absence of invisible ink will prevent the sensor from detecting incidental artwork as active colors which encode a presentation. The primary function of the invisible ink is error prevention but it also performs the function of adding hidden messages in the system. The hidden messages are illuminated by the violet LEDs. FIGS. 2A-B illustrate a flashlight detector for use in reading educational materials in an exploded view and a side view, respectively. Flashlight 200 includes an outer housing with an outer case 202 and 204 and a clear plastic cone 206 . It includes battery compartment 208 , battery cover 210 , battery cover screw 212 and batteries 214 . Flashlight 200 includes an onboard circuit with software to measure the color values of the colored areas enclosed in embedded memory module 216 inserted into memory module slot 218 . Module 216 contains stored audio files, memory module contacts 220 , an onboard speaker 222 to play a specific, pre-loaded audio file. Speaker 222 is activated by FM transmitter 224 and is covered by speaker cap 226 . An LED power switch 228 is activated by the sensor when violet light from the invisible medium, is detected by optical color sensor 230 within inner sensor housing 232 . The sensor is preferably a Taos 230 color sensor, which is a RGB sensor, although an equivalent RGB or CMYK sensor could also be used. LED power switch 228 causes the flashlight to emit light within the visible spectrum from white LED 234 and violet LED 236 . The system plays a sound coded for by a discrete coded zone in the visually colored area of FIG. 1B . The sound signal is triggered when a particular wavelength of light, reflected from the visually colored area, is detected and activates switch 228 . Flashlight 200 also includes headphone jack 233 for headphones so that the reader can hear the audio signals without disturbing or distracting others. The device contains USB jack 240 . FIGS. 3A-F illustrate a further embodiment of the invention including a stylus detector 300 for use with printed or other materials of the invention, from different viewpoints. Stylus detector 300 contains LED screen 302 where an image can be presented. The stylus contains several buttons which allow the user to direct the detector, including a next chapter button 304 , a previous chapter button 306 , a next track button 308 , a previous track button 310 and a play/pause button 312 . Stylus 300 can emit and detect light of various wavelengths. It emits light through white LED 314 and violet LED 316 . It detects light in sensor 318 and sensor housing 320 . The stylus detector can be connected to headphones via headphone jack 322 . The device is encased in contoured housing 324 made of plastic or other flexible material. FIG. 4 illustrates an exploded view of a download station 500 used in synchronizing the reader with a computer (not shown). The system depicted can detect colors on printed material that correspond to an internet address containing a predetermined output presentation, such as streaming flash animation on a web browser. Download cradle base 502 contains a well 504 for insertion of the reader or stylus. A USB cable 506 connects the base to the USB port of a computer. The system also employs a PCB 508 and a bluetooth wireless receiver 510 for detecting the signal sent from the reader or stylus after it encodes the hyperlink through wireless transmission. A processor 512 processes the hyperlink. The download cradle includes power conditioner 514 and charging pin 516 . While the configuration shown in FIG. 4 depicts a download station with a cradle base designed for insertion of the handheld read, the download system can alternatively be a cable which connects directly to the handheld reader. Embodiments of the invention can be used for educational and entertainment purposes. One embodiment is a book for children 2-8 years old which assists in reading or learning a language. The system will enable the user to hear associated sounds and hidden messages encoded in the printed material that are detected by the reader. The printed pages contain a layer of invisible ink on and/or surrounding colored zones on the pages which code for sounds and/or reveal hidden messages, such as the hidden word illustrated in FIG. 1C . The books may include discrete circles of solid visible colors on the pages and behind various flaps built into the pages. The circles are printed in a uniform, solid color, but each circle differs from the others in color value, and will include a layer of invisible ink on and/or surrounding the circle. In a preferred embodiment, the layers of invisible ink are printed in circles that are approximately one half of the diameter of the visible circles. These smaller invisible ink circles are centered within the colored circles. Hidden messages can also be printed on the visible circles using invisible ink. These are printed between the outer edge of the invisible circle and the outer edge of the visible colored circle, as depicted in FIG. 1B . The invisible ink cannot be seen by the user without the reader but is detectable with the reader. If the reader detects the presence of invisible ink on and/or surrounding a visible colored circle, when the sensor of the reader is placed over the circle, the device will measure the color value of the visible colored circle. After measuring the color value of the visible circle, the reader will play a corresponding audio file associated with the color that has been measured. All audio files are stored on the flash memory chip installed in the reader prior to operation. Different flash memory chips can be provided that correspond to the various audio files contained in a particular book. In one embodiment, when playing the sound file, the device will activate the additional 405 nm violet LEDs outside the inner tube. This violet light illuminates the hidden word or text message printed on the colored circles. As shown in FIG. 1C , this word may correspond to the visible artwork on the page, as well as to the sounds that the device plays after measuring the color value. When using the device, the user first opens the book and looks at the page. The user identifies a colored circle printed on the page. The user then places the reader onto the center of the circle so that the inner sensor housing is placed in direct contact with the colored circle. A manually operated switch built into the face of the reader activates a 405 nm violet LED in the sensor. If invisible ink is present on the surface at which the reader is directed, the invisible ink will fluoresce and light from that fluorescence will be detected by the light detector. A switch activated by the light detector will turn off the 405 nm violet LED inside the sensor and turn on the white LED inside the sensor. The violet LEDs outside the sensor and inside the outer tube will also be turned on. The color sensor then measures the visible color value of the circle. The detector and an associated processor then plays the corresponding sound file through the onboard speaker, onboard headphone jack, or external FM radio via the onboard FM transmitter, as shown in FIGS. 2A-B . The two violet LEDs activated outside the sensor housing illuminate the hidden word written in the invisible ink. Once the device has detected the discrete coded zone, the device will play the sound to completion without interruption, even if the user removes the reader and sensor to break contact with the surface of the printed material. However, the reader will release the pressure switch built into the face of the reader if the user moves the reader to another colored circle and the presence of another discrete coded zone is detected. The device will cease playing the audio file and will commence playing a new audio file corresponding to the new coded zone. If no discrete coded zone is detected in the new position, the device will continue to play the first audio file to completion without interruption. In another embodiment, the invention can be used by students and adults in a modified form, as indicated in FIGS. 3A-F . The modified student/adult reader shown in FIGS. 3A-F does not include a light cone for revealing hidden messages. However, this reader includes a multipurpose USB computer station, as shown in FIG. 4 . The student/adult reader additionally includes a wireless internet hyperlinking transmitter that communicates between the device and computer station. This station, shown in FIG. 4 , performs three functions. First, it serves to recharge the rechargeable battery inside the reader. Secondly, the download station depicted in FIG. 4 allows for wireless reception of internet hyperlink triggers from the reader and communicates those hyperlink triggers to a computer connected to the internet via USB cable or an equivalent. Finally, the station serves to download new internet-based audio files into the device in a manner similar to many MP3 players known in the art. The student/adult reader, like the child reader, detects colors printed onto the pages of text books or other printed surfaces by detecting colors of different wavelengths printed on the page. Active colors may be printed in small (¼″.times.⅝″) rectangles or ellipses. The shapes for these zones may be used to designate the types of medium to which it links, e.g., rectangles may play sounds, ellipses may hyperlink to web-based media, etc. The rectangles or ellipses can be covered by a layer of invisible ink to enable the device to recognize the colors as active and/or may be surrounded by a zone of invisible ink. The invisible ink may completely or partially overlay the colored zone. The adult/child reader pulses a 405 nm violet light at the target. If invisible ink is detected, the reader measures the visible light associated with the particular coded zone printed on the page. The coded zones may be circles, rectangles or ellipses separated from the images on the page or may be printed in smaller color patches or included in the artwork or the text. The light cone depicted in FIGS. 2A-B is included with the children's embodiment. The outer housing permits the child to register the reader on the coded zone. The student/adult reader does not include an outer housing. It can read a coded zone of any shape but the opening in the sensor housing must be large enough and configured so that it can effectively read the coded zone at which it is directed. In another embodiment, the invention can be used for entertainment purposes such as a board game. The board games are printed in a manner similar to books, and can employ either the children's or student/adult version of the reader. The board games are used like the books and are printed with both invisible and visible inks that can be detected and measured. Hidden messages in a children's version, audio messages and computer hyperlinked media in a student/adult version will direct and inform the user of the board game. Another embodiment of the invention includes multimedia printed exhibits. The exhibits may be designed in concert with either of the two readers described. As with the board games, the exhibit is printed in advance with visible and invisible colors corresponding to specific audio or web based media. Another embodiment of the invention includes additional means whereby the discrete coded zone becomes additionally perceptible. This can be accomplished by using different substances for the discrete coded zone which produce different reactions when illuminated by one or more wavelength of light. These means include, but are not limited to, fluorescence, color shifting, and infrared ink.
A media asset system and method is provided comprising a handheld reader having a sensor enabled to detect a discrete coded zone within a visual image, with the reader capable of producing an output signal corresponding to the discrete coded zone. An output device responds to the output signal with an audio output presentation corresponding to the discrete coded zone. Output is responsive to the reader's selection of output action, and may also be provided for in a video presentation.
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RELATED APPLICATION [0001] This application is a Divisional Application relating to and claiming the benefit of U.S. Non-provisional patent application Ser. No. 13/670,600 filed Nov. 7, 2012, which is based on and claiming the benefit of U.S. Provisional Patent Application Ser. No. 61/556,857 filed Nov. 8, 2011. BACKGROUND [0002] This invention relates to optical fiber telecommunications interconnection systems. As used herein, the term telecommunications includes voice, data, audio and video communications. The telecommunications industry has begun employing optical fibers as a means for signal transmissions, including voice, video and data. The primary advantage of optical fibers over copper wire is substantially increased broadband. However, like copper wire systems, optical fiber systems require patching or interconnection between incoming land line optical cables and distribution cables which connect to various devices in a building. Typical optical fiber patching systems are shown in U.S. Pat. Nos. 7,672,561 and 6,363,198. These patching systems are usually housed in a panel which is mounted on frames and racks which, in turn, are typically located in a communications closet or a data room. Examples of optical fiber distribution frames and racks are disclosed in U.S. Pat. Nos. 5,497,444 and 5,758,003. [0003] It is important that these panels are readily accessible by a technician and, in addition, it is important that the interconnections are easy to make. Also, because of the large number of cables which are being interconnected within a panel, it is important that the cables be managed in such a way that when the technician handles the cables, excess bending of the cables does not occur and the cable remains organized. SUMMARY OF THE INVENTION [0004] In accordance with one form of this invention, there is provided a telecommunications patching system, including a panel. At least one cassette is provided and is adapted to be movably received in the panel. The cassette receives a plurality of telecommunication connector jacks. Each jack has a front cavity adapted to receive a patch cord plug having a patch cord cable extending therefrom. The cassette has first and second ends. A tab extends from and is attached to the first end of the cassette such that the cassette may readily be moved to different positions in the panel. The tab includes a first cable guide. BRIEF DESCRIPTION OF THE DRAWINGS [0005] FIG. 1 is a perspective view of a panel in accordance with the teachings of this invention. [0006] FIG. 2 is a perspective view of three of the panels shown in FIG. 1 stacked and mounted on rack uprights. [0007] FIG. 2A is a perspective view showing the bracket shown in FIG. 2 . [0008] FIG. 2B is an exploded view of the bracket of FIG. 2A . [0009] FIG. 3 is a perspective view of the rack of FIG. 1 with top covers removed illustrating the cassettes. [0010] FIG. 4 is a perspective view of a cassette of FIG. 3 . [0011] FIG. 5 is a perspective view of a cassette of FIG. 3 showing patch cord cables extending from the cassette. [0012] FIG. 6 is a more detailed view of a portion of FIG. 3 but at a different angle. [0013] FIG. 7 is a perspective view of a cable management clip shown in FIG. 3 . [0014] FIG. 8 is a side elevational view of the clip of FIG. 7 . [0015] FIG. 9 is a perspective view of the panel of FIG. 1 with the rear cover removed. [0016] FIG. 10 is a more detailed perspective view of the trunk cable capture mechanism shown in FIG. 9 . [0017] FIG. 11 is a side elevational view of the top portion of the trunk cable capture mechanism of FIG. 10 . [0018] FIG. 12 is an exploded perspective view showing the bottom and top portion of the trunk cable capture mechanism of FIG. 10 . [0019] FIG. 13 is a detailed view showing a portion of the bottom of the trunk cable capture mechanism of FIG. 10 . DESCRIPTION OF THE PREFERRED EMBODIMENT [0020] There is provided an improved high density telecommunications patching system including an improved panel and an improved cassette which is received within the panel which contains telecommunication connector jacks, preferably fiber optic jacks. As used herein, the term “jack(s)” includes any female connector(s) such as optical couplers and electrical jacks and the term “panel” includes enclosures and their panels which house cassettes. [0021] FIG. 1 shows patching system 10 including panel 12 having top portions 14 and 16 which are readily removable for easy access by a technician and top portion 18 which is less readily removable. Panel 12 also includes front cover 20 mounted to hinges 22 and 24 . Brackets 26 and 28 are respectively connected to rack uprights 34 and 36 , shown in FIG. 2 , which engage with the sides 30 and 32 of panel 12 . Brackets 26 and 28 enable panel 12 to be slidably mounted to the rack. As further illustrated in FIG. 2 , a plurality of panels, such as panels 12 and 12 A, are adapted to be mounted on uprights 34 and 36 . Again, as illustrated in FIG. 2 , panels 12 and 12 A are mounted horizontally and may be offset from one another since the panels may be slid on brackets 26 and 28 . Since brackets 26 and 28 are identical, only bracket 26 will be described below. [0022] FIG. 2A shows “L” shaped bracket 26 having holes 27 and 20 which align with the holes 31 on upright 34 for adjusting the vertical position of panel 12 . Screws are received in holes 27 , 29 and 31 and are secured by bolts (not shown). Bracket 26 includes elongated rail 33 which interfaces with channel 35 on side 30 of panel 12 , as shown in FIG. 2 , enabling the panel 12 to be slid to various positions. Channel 35 includes aperture 35 A receiving spring clip 37 . Spring clip 37 is attached to L-shaped support 39 . Spring clip 37 is bowed outwardly. Channel 35 on side 30 of panel 12 includes pocket 41 which captures bowed out portion of spring clip 37 to hold the panel in a predetermined but movable position. Thus, panels 12 and 12 A may be offset from one another within the rack to enable a technician to more easily access the panels. [0023] FIG. 3 shows panel 12 with top portions 14 and 16 removed and with the front 20 in its open position, allowing access to the interior of panel 12 by a technician. Panel 12 receives four rows 38 of cassettes 40 which are better illustrated in reference to FIG. 4 . Each row 38 includes three, preferably identical, cassettes 40 which are stacked adjacent to one another. The cassettes 40 are slidably received within panel 12 . With tops 14 and 16 removable, a technician can easily access the cassettes by sliding them forward or backward from their normal positions under top 18 . [0024] Referring now more particularly to FIG. 4 , cassette 40 includes top 41 , sides 44 and 46 , front 48 and rear 50 . Front 48 preferably receives up to six telecommunication connector jacks 52 which may be electrical but are preferably optical. In the embodiment shown in FIGS. 4 and 5 , each jack 52 includes two cavities for receiving two plugs 65 . Rear 50 preferably includes three optical fiber jacks 54 . Alternatively, jacks 54 may be omitted and cable connections may be made directly to jacks 52 . The optical fiber jacks 52 on the front 48 of the cassette 40 are adapted to be connected to optical fiber cable which is to be distributed to various devices and outlets in a building. Optical fiber jacks 54 on the rear 50 of cassette 40 are adapted to be connected to optical fiber trunk cable corning from outside of the building, such as from a telephone company central office or data center. Jacks 52 and 54 are connected together within cassette 40 by known optical fiber interconnection techniques. Elongated tab 56 is attached to and preferably made integral with the front 48 of cassette 40 . Tab 56 includes cable guides in the form of channels 58 and 60 . Cassettes 40 may also be reversed from the direction show in FIG. 3 . That is, front 48 of cassette 40 could face the rear of panel 12 . [0025] As illustrated in FIG. 5 , cable guide 58 receives, holds, guides and organizes patch cord cables 62 attached to the right six plugs 63 which are adapted to be connected to the right three jacks of cassette 40 and cable guide 60 receives, holds, guides and organizes patch cord cables 64 attached to the left six plugs 65 which are adapted to be connected to the left three of the jacks 52 . Tab 56 not only guides and organizes cables 62 and 64 , but also serves as a handle so that cassette 40 can be easily pulled out of and pushed back into position in panel. Tab 56 , which includes gripping region 67 , therefore enables the technician to easily move the cassette 40 within panel 12 without touching the cables. Thus, tab 56 performs a dual function. [0026] Referring now to FIG. 4 , cassette 40 includes two bow clips 66 connected to sides 44 and 46 . Bow clips 66 function as springs, Cassette 40 includes rails 68 projecting from sides 44 and 46 . Rails 68 are received in grooves 70 in plate 72 , situated between top 18 and bottom 42 of panel 12 as shown in FIG. 6 and between both sides of cassette 40 . The grooves 70 include pockets 74 which are adapted to receive bow clip 66 to help hold the cassette in place. It should be noted, however, that these cassettes 40 are not locked in place by the bow clips 66 and the pockets 74 . The bow clip 66 provides a resistance to movement. However, a technician may readily move the cassette using tab 56 with minimal effort. The positioning of the bow clips and pockets ray be reversed, i.e. the bow clips may be attached within the panel and the pockets may be formed on the sides of the cassettes. [0027] As can be seen in FIG. 3 , panel 12 includes forward side exit cable management devices in the form of multi-channel clips 76 and 78 located on opposing sides at the intersection of the front and sides of panel 12 . Multi-channel clips 76 and 78 are identical and, thus, only multi-channel clip 76 will be further described herein. The channels on clip 76 provide management to the stack of three cassettes on the left side of the panel. [0028] FIG. 7 is a perspective view of multi-channel clip 76 . FIG. 8 is a side elevational view of multi-channel clip 76 . Multi-channel clip 76 includes top channel 80 preferably for receiving cables connected to each of the four top cassettes 40 in the four rows 38 . Middle channel 82 preferably receives cables from the four middle cassettes 40 located in the four rows 38 . Lower channel 84 preferably receives cables from the four lower cassettes 40 in the four rows 38 . By using the three channels 80 , 82 and 84 , cables from the cassettes are appropriately segregated and managed. Multiple channel clip 76 receives cable from the left two rows of cassettes and clip 78 receives cable from the right two rows of cassettes. Multi-channel clip 78 further includes curved guides 86 and 88 which ease cable strain around the perimeter of the side exit. Guide 86 is provided for cable traveling upwardly and guide 88 is provided for cable traveling downwardly and guides the cable in those directions. The multi-channel clips 76 and 78 are held in place at the front side exit of the panel by means of affixing, such as screwing, the multi-channel clips to ears which protrude outwardly from the sides of panel 12 . [0029] As shown in FIG. 8 , the multi-channel clip 76 includes slots 90 and 92 which receive a strap (not shown), such as a cable tie or a strap, to secure the cable when the installation is completed. [0030] FIG. 9 shows panel 12 with readily removable top 14 having been removed. Cable capture mechansms 94 and 96 are provided adjacent to cable exit openings 98 and 100 on the rear portion of the panel 12 . Since both cable capture mechanisms 94 and 96 are identical, only cable capture mechanism 94 will be described in detail herein. [0031] FIG. 10 shows a fully assembled cable capture mechanism 94 . Cable capture mechanism 94 includes a ribbed pad 102 , preferably made of a sot but resilient material such as rubber. Cable capture mechanism 94 also includes removable top plate 104 and ribbed pad mounting plate 106 . Cable capture mechanism 94 is held in place adjacent to opening 98 by bolts 108 and 110 . [0032] As can be seen from FIG. 11 , a second pad 112 is attached to the bottom of removable top plate 104 . Pad 112 includes a plurality of lands 114 . The bottom/top combination of pad 102 and pad 112 captures cable 120 firmly but does not apply excessive force to the fiber in the cable. [0033] As can be seen from FIG. 12 , pad 102 is mounted on plate 106 , Two rows of ribs 116 project upwardly along the edges of pad 102 . Adjacent ribs 116 form grooves 118 for receiving cable 120 . Pad 112 is received between the two rows of ribs 116 when the cable capture mechanism is fully assembled and lands 114 are in register with grooves 118 . [0034] As shown in FIG. 13 , each rib 116 includes projection 122 on either side. Projection 122 helps hold the cable 120 in place within the groove 118 and enables the panel 12 to be used with various diameter cables. Cable capture mechanism 94 provides strain relief for the cables which are received at the rear side of cassette 40 after installation. It also provides for additional cable management. In addition, during cable installation, the individual cables are held in place in grooves 118 so that there is little strain or excess force exerted on the cable during installation and/or service. Also, since the cassettes are slidable within the panel, the installer will leave excess cable between the cable capture mechanism 94 and the cassettes 40 . Since the cable capture mechanism 94 holds the cable in place, strain on the connections of the cable at or in cassette 40 is reduced. [0035] While the preferred embodiment of the invention has been described in reference to optical fiber cables and connectors, it is also applicable to electrical cables and connectors. [0036] From the foregoing descriptions of the embodiments of the invention, it will be apparent that many modifications may be made therein. It will be understood that these embodiments of the invention are exemplifications of the invention only and that the invention is not limited thereto.
A telecommunications patching system is provided having a panel and at least one cassette movably received in the panel. The cassette receives a plurality of telecommunication connector jacks. Each jack has a front cavity adapted to receive a patch cord plug having a patch cord cable extending therefrom. The cassette has first and second ends. A tab extends from and is attached to the first end of the cassette such that the cassette may readily be moved to different positions in the panel. The tab includes a first cable guide.
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CROSS REFERENCE TO RELATED APPLICATIONS [0001] This application relates to and claims priority from JPCT/JP2013/052541 filed Feb. 5, 2013, the entire contents of which are incorporated herein by reference. FIGURE SELECTED FOR PUBLICATION [0002] FIG. 2 BACKGROUND OF THE INVENTION [0003] 1. Field of the Invention [0004] The present invention relates to a pressure control valve applied in the fluid pressure circuit used in an industrial vehicle and a control valve system including a pressure control valve as a constituent element. [0005] 2. Description of the Related Art [0006] Conventionally, referring now to FIG. 5 and as set forth below, a balance piston type valve is known as a pressure control valve and is used in a fluid pressure circuit used for industrial vehicles. This type of pressure control valve V is installed between an input port a 1 c receiving an operation fluid and a tank port a 1 d continuously connected to a tank for storing operation fluid and valve V comprises a main valve element a 6 and a valve seat a 7 a in which the main valve element a 6 can seat and also a main valve unit a 4 formed by utilizing a valve storage body a 7 having a pilot chamber a 7 b in which the main valve element a 6 is slidably stored, the pilot valve element a 8 , and a pilot valve unit a 5 formed by utilizing a pilot valve seat member a 9 having a pilot valve seat a 9 a in which the pilot valve element a 8 can seat and fixedly installed in the main valve unit a 4 . Both the main valve element a 6 and the pilot valve element a 8 are biased by a biasing means a 101 , a 102 (such as a spring) to seat respectively in the main valve seat a 7 a and the pilot valve seat a 9 a . Then, when both the main valve unit a 4 and the pilot valve unit a 5 are in the closed valve state, fluid pressure inside the input port a 1 c is operative to the pilot valve element a 8 through the inside of the pilot chamber a 7 a. [0007] Then, when the inside pressure of the input port a 1 c becomes higher than the predetermined pressure, fluid pressure operative to the pilot valve element a 8 is stronger than the biasing force by the biasing means a 102 and the pilot valve element a 8 separates from the pilot valve seat a 9 a and the pilot valve unit a 5 will be in the open valve state. Then, as the inside of pilot chamber a 7 b continuously connects to the tank port aid, the differential pressure between the inside of input port a 1 c and the inside of pilot chamber a 7 b is generated and the force due to the differential pressure is stronger than the biasing force by the biasing means a 101 so that the main valve element a 6 leaves from the main valve seat a 7 a and the main valve unit a 4 will also be in the open valve state. [0008] Accordingly, while the pilot valve unit a 5 is in the open valve state and the main valve unit a 4 is in the closed valve state, operation fluid flows through the gap between the pilot valve seat a 9 a and the pilot valve element a 8 of the pilot valve seat member a 9 , but unfortunately the central axis of the pilot valve seat a 9 a and the central axis of the pilot valve element a 8 may not be always coaxial and also the back-and-forth direction of the pilot valve element a 8 may not be the same as the extending direction of the central axis of the pilot valve element a 5 . Therefore, in the case of these situations the pilot valve element a 8 is eccentric relative to the pilot valve seat a 9 a and operation fluid flows through the gap, the problem takes place, wherein as a result the pilot valve element a 8 can vibrate due to the fluid pressure of fluid and collides with the pilot valve seat member a 9 to make abnormal noise, causing premature wear, leakage and other defects. [0009] One construction in an effort to solve such problems is disclosed in which a guide to keep slidably the pilot valve element is installed to make the back-and-forth direction of the pilot valve element as the same as the extending direction of the central axis of the pilot valve element (e.g., Patent Document 1, the entire contents of which are incorporated by reference). [0010] However, unfortunately according to the constitution disclosed in Patent Document 1, since the guide member must be additionally installed and modified, the number of parts and assembly processes increase so that an increase of the production cost can be raised as another problem. PRIOR ART DOCUMENTS Patent Document 1: JP Patent Published H11-311349 ASPECTS AND SUMMARY OF THE INVENTION Problems to be Solved by the Invention [0011] The purpose of the present invention, focusing on the above points, is to prevent or suppress an occurrence of the defect making an abnormal noise without increasing the number of parts and assembly processes, which takes place when the pilot valve unit is in the open valve state and the pilot valve element vibrates because of receiving fluid pressure and collides with the pilot valve seat member. Means for Solving the Problem [0012] A pressure control valve of the present invention has the following construction. Specifically, the pressure control valve of the present invention is the pressure control valve including: a main valve element and a main valve seat in which the main valve element can seat and also a main valve unit including a valve storage body having a pilot chamber in which the main valve element is slidably stored; a pilot valve seat member including a pilot valve element and a pilot valve seat in which the pilot valve element can seat; and a pilot valve unit that will open as the pilot valve element separates from the pilot valve seat when the pressure of the inside of the pilot chamber becomes higher than the predetermined pressure of the spring urging force, wherein a concave part forming the flow passage for the operation fluid in between the pilot valve element when said pilot valve unit is in the open valve state is separated from each other with the same angle and formed at more than three places in the pilot valve seat member, and also each concave part has the identical shape. [0013] Further, the control valve of the present invention includes at least a casing in which an input port receiving the operation fluid and an open tank port continuously connecting to an external storage tank (not shown), and the control valve installed between the input port and the tank port inside the casing. [0014] Accordingly, during a use the present invention pilot valve element receives the fluid pressure from the operation fluid flowing through each flow passage but a perpendicular component, relative to the back-and-forth direction of the composition of fluid pressures from the operation fluid flowing through each flow passage, is erased because each adjacent flow passage separates (or estranges) with the same relative angle and each concave part has the identical shape. As a result, a member guides the back-and-forth direction of the pilot valve element installed so that the defect making an abnormal noises is prevented or suppressed without increasing the number of parts and assembly processes, which takes place when the pilot valve element takes the open valve position, and also prevents the pilot valve element vibrating because of receiving the fluid pressure that collides with the pilot valve seat member. Effects of the Invention [0015] According to the present invention and construction thereof, the occurrence of the defect making an abnormal noise is prevented or suppressed without increasing the number of parts and assembly processes, which takes place when the pilot valve unit is open, and it is now recognized that the pilot valve element vibrates because of receiving fluid pressure and in response collides with the pilot valve seat member. [0016] According to the present invention, a pressure control valve includes a main valve unit provided with a main valve element and a valve housing body having a main valve seat capable of seating the main valve element and having a pilot chamber for slidably housing the main valve element. A pilot valve unit is provided with a pilot valve element and a pilot valve seat member has a pilot valve seat capable of seating the pilot valve element and separating the pilot valve element from the pilot valve seat and opening when a pressure in the pilot chamber exceeds a predetermined pressure. The pressure control valve is configured with recessed parts that form hydraulic fluid channels between the pilot valve seat member and the pilot valve element when the pilot valve unit is in an open state at three or more locations so as to be separated by equal angles. Each of the recessed parts has the same shape. [0017] The above and other aspects, features and advantages of the present invention will become apparent from the following description read in conjunction with the accompanying drawings, in which like reference numerals designate the same elements. BRIEF DESCRIPTION OF THE DRAWINGS [0018] FIG. 1 is a schematic diagram illustrating a control valve of the present invention. [0019] FIG. 2 is a schematic diagram illustrating a pressure control valve of the invention. [0020] FIG. 3A is a front view illustrating a control valve seat member of the invention. [0021] FIG. 3B is a cross-sectional side view along line 3 B- 3 B in FIG. 3A . [0022] FIG. 4 is an explanatory drawing illustrating the behavior of the pressure control valve of the present invention in a movement position. [0023] FIG. 5 is a schematic diagram illustrating a conventional pressure control. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [0024] Reference will now be made in detail to embodiments of the invention. Wherever possible, same or similar reference numerals are used in the drawings and the description to refer to the same or like parts or steps. The drawings are in simplified form and are not to precise scale. The word ‘couple’ and similar terms do not necessarily denote direct and immediate connections, but also include connections through intermediate elements or devices. For purposes of convenience and clarity only, directional (up/down, etc.) or motional (forward/back, etc.) terms may be used with respect to the drawings. These and similar directional terms should not be construed to limit the scope in any manner. It will also be understood that other embodiments may be utilized without departing from the scope of the present invention, and that the detailed description is not to be taken in a limiting sense, and that elements may be differently positioned, or otherwise noted as in the appended claims without requirements of the written description being required thereto. [0025] Various operations may be described as multiple discrete operations in turn, in a manner that may be helpful in understanding embodiments of the present invention; however, the order of description should not be construed to imply that these operations are order dependent. [0026] Hereafter, the inventor sets forth the first Embodiment of the present invention referring FIG. 1-FIG . 4 . [0027] Referring to FIG. 1 , the control valve C of the present invention is used in a fluid pressure system applied for the industrial vehicles and includes at least a casing 1 , a flow dividing valve 2 mountable to the casing 1 , and a pressure control valve 3 operably mountable to casing 1 . A pressured oil input port 1 a operates as an input port receiving an operation fluid (fluid not shown), a steering passage 1 b is provided to operably discharge the operation fluid to the fluid pressure system, not shown in FIG., to control the steering of a vehicle (not shown) during a use. A loading and unloading passage 1 c is provided to discharge the operation fluid to the fluid pressure system (complete system not shown), to control a loading and unloading equipment of a vehicle. A low pressure passage 1 d is positioned as the tank port continuously connecting to the tank (not shown) to store the operation fluid in an operable manner in casing 1 . Flow dividing valve 2 is installed inside a flow dividing valve storage hole 1 e continuously connected to pressured oil input port 1 a , steering passage 1 b and loading and unloading passage 1 c is operative to inlet a part of the operation fluid input from pressured oil input port 1 a via the continuous passage installed in the inside thereof to the steering passage 1 b and also to inlet the remaining operation fluid input from the pressured oil input port 1 a by operably changing the opening level corresponding to an inside pressure of the pressured oil input port 1 a to the loading and unloading passage 1 c. [0028] Pressure control valve 3 , installed between the loading and unloading passage 1 c and the low pressure passage 1 d , includes a main valve unit 4 and a pilot valve unit 5 , as shown. [0029] Here, as will be understood from study of the provided disclosure, the operation fluid input from pressured oil input port 1 a to control valve C, as set forth above, is divided into steering passage 1 b and loading and unloading passage 1 c via flow dividing valve 2 during a use thereof. Accordingly, when, during a use, the fluid pressure of the operation fluid divided into the loading and unloading passage 1 c becomes higher than the permitted predetermined pressure; firstly the pilot valve unit 5 of the pressure control valve 3 will open and then the main valve unit 4 will open. At that time, upon such opening, the operation fluid flows out from the loading and unloading passage 1 c to the low pressure passage 1 d. [0030] Specifically, the pressure control valve 3 functions to control the pressure inside the loading and unloading passage 1 c so as to not be higher than the predetermined pressure (e.g., a release pressure). [0031] Hereafter, the inventor sets forth the specific constitution of the pressure control valve 3 . [0032] Referring additionally to FIG. 2 , pressure control valve 3 includes a main valve element 6 and a main valve seat 7 a in which main valve element 6 can seat during a use, and also a main valve unit a 4 formed by utilizing a valve storage body 7 having a pilot chamber 7 b in which the main valve element 6 is slidably stored, a pilot valve element 8 , and a pilot valve unit 5 formed by utilizing a pilot valve seat member 9 having a pilot valve seat 9 a in which the pilot valve element 8 can seat fixedly installed in the main valve unit 4 during a use. Further, as set forth above, the pressure control valve 3 is installed between the loading and unloading passage 1 and the low pressure passage 1 d , by which during a use when the pilot valve unit 5 and the main valve unit 4 are open, the loading and unloading passage 1 c and the low pressure passage 1 d are continuously connected and in other cases, in-between of the loading and unloading passage 1 c and the low pressure passage 1 d is blocked. [0033] Main valve unit 4 is formed by utilizing the main valve element 6 and the valve storage body 7 having the main valve seat 7 a in which the main valve element 6 can seat. The main valve element 6 that is a bottomed cylindrical member having internal space 6 a open in the opposite direction to the direction toward the main valve seat 7 a comprises an orifice continuously connecting the internal space 6 a and the loading and unloading passage 1 c . On the other hand, the valve storage body 7 comprises the first sleeve 71 arranged in the side of the loading and unloading passage 1 c and the second sleeve 72 which stores a part of first sleeve 71 in the one end and of which the other end is mounted to casing 1 . First sleeve 71 is the cylindrical member having the operation fluid input port 71 a continuously connecting to the loading and unloading passage 1 c at the end of the side toward loading and unloading passage c and also having a first operation fluid discharge port 71 b continuously connecting to the low pressure passage 1 d in the side surface and is formed as pilot chamber 7 b inside which the main valve element 6 is slidable. Main valve seat 7 a is formed at the upstream side edge of pilot chamber 7 b . Second sleeve 72 is connected to the opposite side edge of the operation fluid input port 71 a of the first sleeve 71 with a screw (not shown, or other connection mechanism) and stores the pilot valve element 8 of the pilot valve unit 5 in the inside thereof. Second sleeve 72 includes the second operation fluid discharge port 72 a continuously connecting the internal space and low pressure passage 1 d . During a use, main valve unit 4 selects either a closed-valve-state in which main valve element 6 seats in main valve seat 7 a or the open-valve-state in which main valve element 6 separates (estranges) from main valve seat 7 a . Further specifically, a spring 101 is operative as a biasing mechanism or means and in use biases main valve element 6 toward main valve seat 7 a between the bottom of the internal space 6 a of main valve element 6 and the bottom of pilot valve seat member 9 ; and when a differential pressure between the inside of the pilot chamber 7 b and the loading and unloading passage 1 c takes place because the pilot valve unit 5 is in the open-valve-state, the operative force due to the differential pressure for main valve element 6 is stronger than the biasing force of spring 101 and main valve unit 4 will advance and move to the open-valve-state. [0034] As set forth above and referring to FIG. 2 , the pilot valve unit 5 is formed by utilizing pilot valve element 8 that is movable back-and-forth in the inside of second sleeve 72 of valve storage body 7 of main valve unit 4 ; and, pilot valve seat member 9 having pilot valve seat 9 a in the inside thereof in which pilot valve element 8 can seat, and fixedly installed in between first sleeve 71 of valve storage body 7 of main valve unit 4 and second sleeve 72 . [0035] Pilot valve element 8 includes valve element main body 81 having approximately conical shape in which the diameter thereof is getting smaller in the direction toward loading and unloading passage c (as shown) and guide unit 82 extends to the opposite direction away from loading and unloading passage 1 c and slides and moves inside second sleeve 72 . [0036] On the other hand, referring additionally to FIG. 3 , pilot valve seat member 9 includes a flange part 91 installed between first sleeve 71 and second sleeve 72 , a mounting part 92 extending from flange part 91 to loading and unloading passage 1 a and installed inside sleeve 71 , and pilot valve seat 9 a at the end of the opposite direction to the direction toward the loading and unloading passage 1 c . During a use, pilot valve unit 5 selects either the closed-valve-state in which pilot valve element 8 seats in main valve seat 9 a or the open-valve-state in which pilot valve element 8 estranges from main valve seat 7 a. [0037] Further specifically, a spring 102 is operable as a biasing mechanism or means and is operable to bias pilot valve element 8 toward pilot valve seat 9 a and is installed between a rear anchor of guide 82 and second sleeve 72 (as noted in FIG. 2 ), and when the fluid pressure induced from loading and unloading passage 1 c into the inside of pilot chamber 7 b via an orifice 6 b of the main valve element is higher than the predetermined pressure (from the spring force of spring 102 ), the operative force due to the fluid pressure for pilot valve element 8 is stronger than the biasing force of the spring 102 and pilot valve unit 5 will be in the open-valve-state. [0038] As noted directly in FIG. 3 , a plurality of concave parts 9 x are formed in the flow passage along seat 9 a for the operation fluid in between pilot valve element 8 , when pilot valve element 8 is in the open-valve-state (is separated) and formed at three and more places in pilot valve seat member 9 each with the same angle. All concave parts 9 x have the identical shape and the bottomed ditch drilled toward outside of pilot valve seat 9 a . Further, each concave part 9 x has an approximately arc shape in the rear view thereof. In addition, the shape of each concave part 9 x can be set as any shape that is operative for the function of concave parts 9 x as discussed herein. [0039] Then, during further operation when the fluid pressure inside the loading and unloading passage 1 c is higher than the predetermine pressure, firstly, the force due to the fluid pressure operative to the pilot valve element 8 becomes stronger than the biasing force operative to the pilot valve element 8 (by spring 102 ); and pilot valve element 8 leaves from pilot valve seat 9 a and pilot valve unit 5 will be in the open-valve-state referring to FIG. 4 . At this time, a gap S is generated between pilot valve element 8 and pilot valve seat member 9 . The width of gap S where concave parts 9 x is installed is larger than other parts and consequently the operation fluid flows mainly inside concave part 9 x . Then, the force due to the fluid pressure of the operation fluid flowing inside the concave part 9 x and operative to the pilot valve element 8 has a component in the leaving direction from pilot valve seat 9 a along with the center of axis of pilot valve element 8 and in the direction toward the center of axis of pilot valve element 8 . However, the concave parts 9 x are estranged (separated) from each other with the same angle and all of them have the identical shape so that all components of the force due to the fluid pressure of the operation fluid and operative to pilot valve element 8 in the direction toward the center of axis have the same severity and the forces are therefore compensated and erased each other. Accordingly, when pilot valve element 8 is in the open-valve-state, the force due to flow of the operation fluid has only the component in the aligned leaving direction from pilot valve seat 9 a along with the center of axis of pilot valve element 8 . Then, the operation fluid inside pilot chamber 7 b is discharged to low pressure passage 1 d via second operation fluid discharge port 72 a and the differential pressure between loading and unloading passage 1 d and pilot chamber 7 b so that the force due to the differential pressure can be stronger than the biasing force of spring 101 operative to main valve element 6 leaves (separates) from main valve seat 7 a and then main valve unit 4 will be in the open-valve-state. [0040] Specifically, according to the present invention, it will be understood that concave parts 9 x having identical shape are estranged (separated) from each other with the same angle, in the same shape, and are installed at the equally spaced three places in pilot valve seat member 9 (as shown in FIG. 3A ), and when pilot valve element 8 is in the open-valve-state, the operation fluid flows between concave parts 9 x and pilot valve element 8 so that the force due to flow of the operation fluid, as set forth above, has only the force component in the leaving (separation) direction from pilot valve seat 9 a along the center of axis of pilot valve element 8 . Accordingly, the present invention prevents an occurrence of a defect making an abnormal noise occurring when a conventional pilot valve element 8 in the open-valve-state and vibration because of receiving fluid vector pressures colliding with the pilot valve seat member 9 are prevented without increasing the number of parts and assembly processes. [0041] Further, according to the present Embodiment, concave parts 9 x are installed at the three places (in the preferred embodiment) so that a minimum number of processes can bring the realization of the constitution of pilot valve seat member 9 , by which the above effects can be obtained, and also pilot valve element 8 can be pressed along the same axis mechanically and most stably by the operation fluid flowing inside the concave part 9 x. [0042] Further, it will be understood that the present invention is not limited to the embodiment discussed above. For example, the concave part portions (shown as 9 x ) installed in the pilot valve seat member is not limited to the three places (as shown) and may be installed at more than four places so that the effective impact of the fluid forces also provide co-axial affects and produce no vibration or noise. Also, the present concepts may not only be applied as the constituent element of the control valve used in the industrial vehicles, but also the pressure control valve relative to the present invention may be applied alone as a relief valve opened when the high pressure port fluid pressure in e.g., the fluid pressure circuit is higher than the predetermined fluid pressure. [0043] Further the present invention can be modified within the scope and spirit of the present disclosure in a variety of aspects unless otherwise departing from the spirit of the present invention. INDUSTRIAL APPLICABILITY [0044] The present invention provides industrial applicability since the proposed invention minimizes the abnormal noises and vibration that take place because the present inventive system addresses the vibration caused by the receiving fluid pressure collides with the pilot valve seat, and minimizes the impact thereof without increasing the number of parts and assembly processes. [0045] Having described at least one of the preferred embodiments of the present invention with reference to the accompanying drawings, it will be apparent to those skills that the invention is not limited to those precise embodiments, and that various modifications and variations can be made in the presently disclosed system without departing from the scope or spirit of the invention. Thus, it is intended that the present disclosure cover modifications and variations of this disclosure provided they come within the scope of the appended claims and their equivalents. EXPLANATION OF REFERENCES [0000] C Control valve 1 Casing 3 Pressure control valve 4 Main valve unit 5 Pilot valve unit 6 Main valve element 7 Valve storage body 8 Pilot valve element 9 Pilot valve seat member 9 x Concave parts
A pressure control valve includes a main valve unit provided with a main valve element and a valve housing body having a main valve seat capable of seating the main valve element and having a pilot chamber for slidably housing the main valve element. A pilot valve unit is provided with a pilot valve element and a pilot valve seat member has a pilot valve seat capable of seating the pilot valve element and separating the pilot valve element from the pilot valve seat and opening when a pressure in the pilot chamber exceeds a predetermined pressure. The pressure control valve is configured with recessed (concaved) parts that form hydraulic fluid channels between the pilot valve seat member and the pilot valve element when the pilot valve unit is in an open-valve-state at three or more locations so as to be separated by equal angles. Each recess has the same shape.
5
CROSS REFERENCE TO RELATED APPLICATIONS [0001] This application is a divisional of 11/664,742 filed Apr. 5, 2007, which is the US National Stage of International Application No. PCT/EP2005/054277, filed Aug. 31, 2005 and claims the benefit thereof. The International Application claims the benefits of European application No. 04023702.6 filed Oct. 5, 2004, both of the applications are incorporated by reference herein in their entirety. FIELD OF INVENTION [0002] The present invention relates to a material composition for producing a coating for a component, in particular for a component of a gas turbine installation, such as for example a compressor blade or vane, which is made from a metallic base material. The present invention also comprises a coated metallic component. The invention is suitable, for example, for use in gas turbine installations, in particular for use in compressors of gas turbine installations. BACKGROUND OF THE INVENTION [0003] In its simplest form, a gas turbine installation comprises a compressor, a combustion chamber and a turbine. Intake air is compressed in the compressor, and fuel is then added to it. This is followed by combustion of this mixture in the combustion chamber, with the combustion exhaust gases being fed to the turbine, where their thermal energy is withdrawn and converted into mechanical energy. The compressor is generally driven by the turbine and comprises a multiplicity of compressor blades or vanes. [0004] During compression of the air in the compressor, water may be formed, which under certain circumstances combines with other elements contained in the air to form an electrolyte which can lead to corrosion and erosion at the compressor blades or vanes. To prevent this corrosion and/or erosion, therefore, compressor blades or vanes are generally provided with coatings. Coatings which are particularly suitable in this context are those which comprise a for example phosphate-bonded base matrix with metal particles, such as for example aluminum particles, dispersibly distributed therein. The protective effect of a coating of this type is that the metal particles embedded in the base coating, together with the (more noble) metal of the compressor blade or vane and the electrolyte, from a galvanic cell, in which the metal particles form what are known as sacrificial anodes. The oxidation or corrosion then takes place in the sacrificial anodes, i.e. in the metal particles, and not in the metal of the compressor blade or vane. [0005] The phosphate-bonded base matrix has glass-ceramic properties, is thermally stable, is likewise resistant to the corrosion, and also provides protection against mechanical effects, such as abrasion and erosion. [0006] In addition to the metal particles, the coating may contain further particles as fillers. By way of example, mention may be made at this point of dye particles. [0007] Other types of coatings may be considered as well as phosphate-bonded coatings. EP 0 142 418 B1, EP 0 905 279 A1 and EP 0 995 816 A1 describe chromate/phosphate-based coatings. EP 1 096 040 A2 describes a phosphate/borate-based coating, and EP 0 933 446 B1 describes a phosphate/permanganate-based coating. The coatings described use particle additions with particle sizes of >1 μm Therefore, the coatings have layer structures with grain sizes of over 1 μm. To obtain a smooth blade or vane outer surface, therefore, a particularly suitable outer coating, known as the top coat, is applied above a primer layer, known as the base coat, of this type. SUMMARY OF INVENTION [0008] It is an object of the present invention to provide a material composition which is advantageous compared to the prior art for the production of a coating of a component made from a metallic base material, in particular a turbine component, more particularly a compressor blade or vane or a turbine blade or vane. [0009] A further object of the present invention is to provide an advantageous coated metallic component, in particular a turbine component, and more particularly a compressor blade or vane or turbine blade or vane. [0010] The first object is achieved by the process as claimed in the claims, and the second object is achieved by the coated component as claimed in the claims. The dependent claims contain advantageous configurations of the invention and can be combined with one another in any desired way. [0011] A material composition according to the invention for the production of a coating for a component, in particular for a turbine component which is made from a metallic base material, i.e. from a metal or a metal alloy comprises a matrix material to form a base matrix of the coating, and at least one filler material for setting desired coating properties and/or coating features. The matrix material may in particular have glass-ceramic base properties. The material composition according to the invention is distinguished by the fact that the matrix material and/or the filler material comprise(s) nanoparticles with particle sizes of less than 1 μm. It is preferable for the particle sizes of the nanoparticles to be in the range from 50 μm to 200 μm. [0012] The use of nanoparticles serves, inter alia, to set an ultrafine layer microstructure. It is in this way possible to improve properties which are dependent on grain size, for example fracture toughness, strength, resistance to thermal shocks, etc., of the layer microstructure. On account of their high surface energy, materials with a grain size in the nanometer range have an extremely high sintering activity. The high number of interfacial atoms and the short diffusion paths in the nanoparticles mean that sintering of the material composition is possible at a temperature which is approx. 20% to 40% lower than the melting temperature of the volume-forming material. This in turn is beneficial to the grain growth in the material. [0013] Moreover, it has been found that nanostructured materials used to protect against corrosion are more resistant to corrosive media than the coarse-grained coatings of the prior art. The improved corrosion protection for metals is caused by the presence of a greater number of uniformly finely distributed defects in the passive film, which are located primarily at the grain boundaries. The ultrafine distribution of the defects prevents a high local accumulation of harmful anions (for example chloride, sulphate, etc.). As a result, a greater force is required for anion accumulation and subsequent acidification, with the result that a higher anodic potential is required for stable hole growth. [0014] The material composition with nanoparticles also has other properties which differ greatly from those of coarse-grained material compositions, i.e. compositions with particle sizes of over For example, the typical hardness of metals with particle sizes of approx. 10 μm is higher by a factor of 2 to 7 than the same metal with particle sizes of approx. 1 μm. Moreover, the hard-soft phenomenon of nanostructured materials occurs: hard material becomes more ductile, soft material becomes harder. On account of this hard-soft phenomenon, the material composition according to the invention can produce coatings of reduced brittleness. [0015] In one configuration of the invention, solid constituents of the matrix material are in the form of nanoparticles. Forming the solid constituents of the matrix material as nanoparticles increases the thermal stability, the corrosion resistance as well as the resistance to mechanical effects of a coating produced from the material composition. Moreover, the use of nanoparticles in the matrix material, in particular in conjunction with the use of nanoparticles in the filler material, allows the production of smoother coatings than with the coarse-grained material compositions of the prior art. There is then no longer any need for a top coat. The costs and time required to coat a component can be reduced as a result of elimination of the process steps for production of the top coat. [0016] Suitable nanoparticles for the matrix material are in particular—although not exclusively—materials comprising aluminum (Al), chromium trioxide (CrO 3 ), magnesium oxide (MgO), aluminum oxide (Al 2 O 3 ) and/or boric acid (H 3 BO 3 ). [0017] In a further configuration of the present invention, the filler material comprises metal or metal alloy particles as nanoparticles. As a function of the metallic base material, these particles can be selected in such a manner as to provide a sacrificial anode effect. In other words, the metal or metal alloy of the nanoparticles can be less noble than the metal or metal alloy of the metal base material. [0018] Depending on the metallic base material, the metal or metal alloy particles may comprise at least one of the following metals: aluminum (Al), magnesium (Mg), Iron (Fe), nickel (Ni), cobalt (Co), titanium (Ti) and zinc (Zn). The metals listed are particularly suitable for the coating of blades or vanes which are made from iron-base, nickel-base or cobalt-base superalloy. Alloys of this type typically comprise chromium, titanium, tantalum, aluminum, tungsten and further elements with excellent resistance to high temperatures combined, at the same time, with a high strength. Iron-based base alloys are used in particular to produce compressor blades or vanes, whereas nickel-based or cobalt-based base alloys are used in particular to produce the turbine blades or vanes. An example of a gas turbine blade or vane produced from a superalloy is given in U.S. Pat. No. 5,611,670. Therefore, reference is explicitly made to the disclosure of said document with regard to the composition of possible superalloys for turbine blades or vanes. [0019] Since, on account of their small size, the metal or metal alloy particles have a particularly high reactivity, it is advantageous for them to be deactivated. The deactivation can be realized, for example, by the metal or metal alloy particles comprising an oxide layer, a phosphate layer or a deactivation layer which is compatible with the matrix material and/or further fillers, for example chromate, borate, etc. The deactivation layer can be produced in situ during production of the nanoparticles. This may take place, for example, by controlled addition of precursor compounds or gases. The deactivation of metallic nanoparticles is described, for example, in US 2003/0108459 A1 and in WO 01/58625 A1. Therefore, reference is made to the disclosure of these documents with regard to the deactivation of the metal or metal alloy particles. [0020] In a further configuration of the present invention, the filler material comprises hard-material particles as nanoparticles. The hard-material particles may in particular comprise at least one of the following materials: diamond, silicon carbide (SiC), cubic boron nitride (BN), corundum, etc. The nanoscale hard-material particles can be used to increase the resistance of a coating produced using the material composition according to the invention to mechanical effects. [0021] In yet another configuration of the present invention, the filler material comprises thermally stable particles as nanoparticles. Suitable thermally stable nanoparticles are in particular zirconium oxide (ZrO 2 ), silicon oxide (SiO 2 ), aluminum oxide (Al 2 O 3 ), aluminum-silicon oxide (Al x Si y )O z , etc. The nanoscale thermally stable particles can be used to increase the ability of a coating produced using the material composition according to the invention to withstand thermal stresses. [0022] Moreover, in a further configuration of the material composition according to the invention, the filler material may comprise dry lubricants as nanoparticles. Example of suitable dry lubricants include graphite, molybdenum sulfide MoS 2 , tungsten sulfide WS 2 , ZrO x N y , etc. The dry lubricants can be used to increase the ware resistance of a coating produced using the material composition according to the invention. [0023] Finally, in yet another configuration of the material composition according to the invention, the filler material may comprise colored pigments of at least one pigment type as nanoparticles. The colored pigments can be used to realize a decorative or informative coloring of a coated component. Furthermore, the colored pigments can also contribute to improving the corrosion protection, the thermal stability and the ware resistance of the coated component. [0024] The filler material may also comprise a mixture of various pigment types as nanoparticles, so that a large number of different colors can be realized. [0025] A further aspect of the present invention provides a coated metallic component having a coating which has been produced from the material composition according to the invention. [0026] In one particular configuration of the coated component, its coating has at least two layers, which contain different nanoscale pigment types. It is in this way possible, for example during maintenance or repair work carried out on the component, to use the color to recognize whether or not the top layer of the coating is present. This makes it possible to recognize to what extent the coating is still providing protection, and therefore obviates the need for unnecessary recoating. [0027] The coated metallic component according to the invention may be configured, for example as a component of a turbine installation, in particular as a compressor blade or vane or as a turbine blade or vane. BRIEF DESCRIPTION OF THE DRAWINGS [0028] Further features, properties and advantages of the present invention will emerge from the following description of exemplary embodiments with reference to the accompanying figures, in which: [0029] FIG. 1 shows an exert from a diagrammatic illustration of a coated compressor blade or vane. [0030] FIG. 2 shows an exert from a diagrammatic illustration of a coated compressor blade or vane. [0031] FIG. 3 shows a partial longitudinal section through an example of a gas turbine. [0032] FIG. 4 shows a perspective view of a rotor blade or guide vane of a turbomachine. DETAILED DESCRIPTION OF INVENTION [0033] FIG. 1 diagrammatically depicts an excerpt from a compressor blade or vane 1 as used in a compressor of a gas turbine installation. The base material 3 and a coating 5 applied to the base material 3 can be recognized. [0034] The base material 3 of the compressor blade or vane 1 may be produced, for example, from a superalloy. Superalloys are alloys based on iron, nickel or cobalt, which typically comprise chromium, titanium, tantalum, aluminum, tungsten and further elements with an excellent resistance to high temperatures combined, at the same time, with a high strength. An example of a gas turbine blade or vane produced from a superalloy is disclosed, for example, in U.S. Pat. No. 5,611,670. Therefore, reference is made to said document with regard to the composition of suitable superalloys. In the present exemplary embodiment, the base material is an iron-based alloy. [0035] The coating 5 is an inorganic coating to protect the compressor blade or vane 1 against corrosion and wear. It comprises an inorganic binder made from chromate/phosphate compounds and metal particles, for example spheroid aluminum particles, dispersively distributed in the binder, as a pigment. [0036] The coating can be effected, for example, by spraying on the following material composition: 7% by weight chromium trioxide (CrO 3 ), 25% by weight phosphoric acid (H 3 PO 4 ), 6% by weight magnesium oxide (MgO) and 62% by weight water (H 2 O) as binder and aluminum particles with a mean diameter in the range from 90 to 110 μm as pigment. The production of aluminum particles of this type is described, for example, in WO 01/58625 A1. Therefore, reference is made to the disclosure of said document with regard to the production of the nanoscale aluminum particles. The composition of the binder and of further suitable chromate/phosphate-based binders are described in EP 0 142 418 B1. Furthermore, further possible coating compositions based on chromate/phosphate are described in EP 0 905 279 A1 and in EP 0 995 816 A1. Therefore, reference is made to said documents with regard to the chemical composition of chromate/phosphate-based coatings. [0037] Unlike in the coating compositions mentioned therein, however, in the coating composition according to the invention described with reference to FIG. 1 , the pigment is realized in the form of nanoscale particles. In the documents mentioned, by contrast, the diameters of the filler particles are in the μm-range. [0038] The nanoscale metal particles or metal alloy particles added are used in particular as sacrificial anodes of the coating. Therefore, as a function of the composition of the base material, the metal should be selected in such a way that it is less noble than the base alloy, in order to ensure the sacrificial anode action. It is therefore preferable to use aluminum. [0039] After the coating composition described has been sprayed onto the base material 3 of the compressor blade or vane 1 , the composition is allowed to dry out, so that the binder then forms the layer matrix in which the nanoscale aluminum particles are embedded. [0040] In a modification of the exemplary embodiment described, instead of the aluminum particles or in addition to the aluminum particles, it is also possible for the solid constituents of the binder, i.e. in the present exemplary embodiment for example the chromium trioxide and the magnesium oxide, to be in the form of nanoscale particles. [0041] In general, the use of nanoscale particles serves to set an ultrafine layer microstructure. It is in this way possible to produce particularly smooth coatings, with the result that in the exemplary embodiment illustrated in FIG. 1 a top coat is not required. [0042] As an alternative or in addition to the nanoscale pigments and/or aluminum particles, it is also possible for nanoscale hard-material particles, for example diamond, silicon carbide (SiC), etc. to be added to the coating described, in order to increase the resistance to mechanical effects, for example abrasion or erosion. It is also possible to add temperature-resistant nanoscale compounds, such as for example zirconium oxide (ZrO 2 ), silicon oxide (SiO 2 ), etc., in order to increase the ability of the coating to withstand thermal stresses. Finally, it is also possible to add nanoscale dry lubricants, for example graphite, molybdenum sulphide (MoS 2 ), etc., in order to set the coating wear resistance. [0043] FIG. 2 shows an excerpt from a coated compressor blade or vane 10 as a second exemplary embodiment of the present invention. The figure illustrates the base material 13 , which can be of the same structure as the base material 3 of the first exemplary embodiment, as well as a coating 15 applied to the base material 13 . In the second exemplary embodiment, the coating comprises a first layer 17 and a second layer 19 applied above the first layer 17 . The chemical composition of both the first layer 17 and the second layer 19 of the coating 15 corresponds to the coating 5 of the first exemplary embodiment. [0044] Unlike in the coating 5 of the first exemplary embodiment, suitable colored pigments in the form of nanoscale colored pigment particles have additionally been added to the coating 15 of the second exemplary embodiment. Colored pigments are described, for example, in EP 0 905 279 A1, or are known as “color index” pigments (The Society of Dyers and Colorists). The desired coloring of the coating which is to be achieved through the addition of the colored pigments can be achieved by mixing various types of colored pigments. Unlike the known colored pigments, the colored pigments in the material composition according to the invention are added in the form of nanoscale particles. [0045] In the present exemplary embodiment, a different type of colored pigment is added to the first layer 17 of the coating 5 from the type of colored pigment added to the second layer 19 . It is in this way possible, when inspecting a blade or vane which has already been in operation, to use the color to ascertain the extent to which the coating has worn away. As soon as the second layer 19 has worn away, the color of the coating changes. It is in this way possible to demonstrate the need to refurbish the compressor blade or vane. Of course, it is also possible to use more than two differently colored layers. [0046] The coating compositions described thus far have contained chromate/phosphate-based binders. However, alternative coating compositions may also comprise binders based on phosphate/borate or phosphate/permanganate. [0047] By way of example, a suitable phosphate/borate-based binder may include the following constituents: water, phosphoric acid, boron oxide, zinc oxide and aluminum hydroxide. In a binder of this type too, the solid constituents may be in the form of nanoscale particles. It is in turn possible for nanoparticles, for example aluminum particles or other metal particles with nanoscale dimensions, i.e. with dimensions of less than 75 nm, preferably between 50 nm and 75 nm or preferably between 20 nm and 75 nm, in particular between 20 nm and 50 nm, to be added to the binder. As an alternative or in addition, it is possible for the nanoscale hard-material particles which have already been mentioned above and/or the abovementioned temperature-resistant particles and/or the abovementioned dry lubricants and/or the abovementioned nanoscale colored pigments to be added. Suitable compositions of phosphate/borate-based binders are described, for example, in EP 1 096 040 A2. Therefore, reference is made to the disclosure of said document with regard to the composition of possible binders for the coating composition according to the invention. [0048] A suitable phosphate/permanganate-based binder may, for example, comprise the following constituents: 67% by weight water, 2% by weight magnesium permanganate, 23% by weight of 85% strength phosphoric acid and 8% by weight aluminum hydroxide. As in the other coatings described, the solid constituents of the binder composition may be in the form of nanoscale particles. Moreover, all the additions which have been mentioned in connection with the other exemplary embodiments in the form of nanoscale particles can also be added. Other possible chemical compositions for coatings based on phosphate/permanganate are described in EP 0 933 446 B1. Therefore, reference is made to the disclosure of said document with regard to suitable chemical compositions of possible binders for the coating composition according to the invention. [0049] In the exemplary embodiments, the solids of the binders are in the form of nanoscale particles. However, it is also possible for the solids of the binder not to be in the form of nanoscale particles. In this case, one or more of the abovementioned additives are present, with at least one of the additives being in the form of nanoscale particles. [0050] FIG. 3 shows, by way of example, a partial longitudinal section through a gas turbine 100 . In the interior, the gas turbine 100 has a rotor 103 which is mounted such that it can rotate about an axis of rotation 102 and is also referred to as the turbine rotor. An intake housing 104 , a compressor 105 , a, for example, toroidal combustion chamber 110 , in particular an annular combustion chamber 106 , with a plurality of coaxially arranged burners 107 , a turbine 108 and the exhaust-gas housing 109 follow one another along the rotor 103 . [0051] The annular combustion chamber 106 is in communication with a, for example, annular hot-gas passage 111 , where, by way of example, four successive turbine stages 112 form the turbine 108 . [0052] Each turbine stage 112 is formed, for example, from two blade or vane rings. As seen in the direction of flow of a working medium 113 , in the hot-gas passage 111 a row of guide vanes 115 is followed by a row 125 formed from rotor blades 120 . [0053] The guide vanes 130 are secured to an inner housing 138 of a stator 143 , whereas the rotor blades 120 of a row 125 are fitted to the rotor 103 for example by means of a turbine disk 133 . [0054] A generator (not shown) is coupled to the rotor 103 . [0055] While the gas turbine 100 is operating, the compressor 105 sucks in air 135 through the intake housing 104 and compresses it. The compressed air provided at the turbine-side end of the compressor 105 is passed to the burners 107 , where it is mixed with a fuel. The mix is then burnt in the combustion chamber 110 , forming the working medium 113 . From there, the working medium 113 flows along the hot-gas passage 111 past the guide vanes 130 and the rotor blades 120 . The working medium 113 is expanded at the rotor blades 120 , transferring its momentum, so that the rotor blades 120 drive the rotor 103 and the latter in turn drives the generator coupled to it. [0056] While the gas turbine 100 is operating, the components which are exposed to the hot working medium 113 are subject to thermal stresses. The guide vanes 130 and rotor blades 120 of the first turbine stage 112 , as seen in the direction of flow of the working medium 113 , together with the heat shield bricks which line the annular combustion chamber 106 , are subject to the highest thermal stresses. [0057] To be able to withstand the temperatures which prevail there, they can be cooled by means of a coolant. [0058] Substrates of the components may likewise have a directional structure, i.e. they are in single-crystal form (SX structure) or have only longitudinally oriented grains (DS structure). [0059] By way of example, iron-base, nickel-base or cobalt-base superalloys are used as material for the components, in particular for the turbine blade or vane 120 , 130 and components of the combustion chamber 110 . Superalloys of this type are known, for example, from EP 1 204 776 B1, EP 1 306 454, EP 1 319 729 A1, WO 99/67435 or WO 00/44949; these documents form part of the disclosure. [0060] The blades or vanes 120 , 130 may also have coatings which protect against corrosion (MCrAlX; M is at least one element selected from the group consisting of iron (Fe), cobalt (Co), nickel (Ni), X is an active element and represents yttrium (Y) and/or silicon and/or at least one rare earth element or hafnium). Alloys of this type are known from EP 0 486 489 B1, EP 0 786 017 B1, EP 0 412 397 B1 or EP 1 306 454 A1, which are intended to form part of the present disclosure. [0061] A thermal barrier coating, consisting for example of ZrO 2 , Y 2 O 4 -ZrO 2 , i.e. unstabilized, partially stabilized or completely stabilized by yttrium oxide and/or calcium oxide and/or magnesium oxide, may also be present on the MCrAlX. Columnar grains are produced in the thermal barrier coating by suitable coating processes, such as for example electron beam physical vapor deposition (EB-PVD). [0062] The guide vane 130 has a guide vane root (not shown here), which faces the inner housing 138 of the turbine 108 , and a guide vane head which is at the opposite end from the guide vane root. The guide vane head faces the rotor 103 and is fixed to a securing ring 140 of the stator 143 . [0063] FIG. 4 shows a perspective view of a rotor blade 120 or guide vane 130 of a turbomachine, which extends along a longitudinal axis 121 . [0064] The turbomachine may be a gas turbine of an aircraft or of a power plant for generating electricity, a steam turbine or a compressor. [0065] The blade or vane 120 , 130 has, in succession along the longitudinal axis 121 , a securing region 400 , an adjoining blade or vane platform 403 and a main blade or vane part 406 . As a guide vane 130 , the vane 130 may have a further platform (not shown) at its vane tip 415 . [0066] A blade or vane root 183 , which is used to secure the rotor blades 120 , 130 to a shaft or a disk (not shown), is formed in the securing region 400 . [0067] The blade or vane root 183 is designed, for example, in hammerhead form. Other configurations, such as a fir-tree or dovetail root, are possible. [0068] The blade or vane 120 , 130 has a leading edge 409 and a trailing edge 412 for a medium which flows past the main blade or vane part 406 . [0069] In the case of conventional blades or vanes 120 , 130 , by way of example solid metallic materials, in particular superalloys, are used in all regions 400 , 403 , 406 of the blade or vane 120 , 130 . Superalloys of this type are known, for example, from EP 1 204 776 B1, EP 1 306 454, EP 1 319 729 A1, WO 99/67435 or WO 00/44949; these documents form part of the disclosure. The blade or vane 120 , 130 may in this case be produced by a casting process, also by means of directional solidification, by a forging process, by a milling process or combinations thereof. [0070] Workpieces with a single-crystal structure or structures are used as components for machines which, in operation, are exposed to high mechanical, thermal and/or chemical stresses. Single-crystal workpieces of this type are produced, for example, by directional solidification from the melt. This involves casting processes in which the liquid metallic alloy solidifies to form the single-crystal structure, i.e. the single-crystal workpiece, or solidifies directionally. In this case, dendritic crystals are oriented along the direction of heat flow and form either a columnar crystalline grain structure (i.e. grains which run over the entire length of the workpiece and are referred to here, in accordance with the language customarily used, as directionally solidified) or a single-crystal structure, i.e. the entire workpiece consists of one single crystal. In these processes, a transition to globular (polycrystalline) solidification needs to be avoided, since non-directional growth inevitably forms transverse and longitudinal grain boundaries, which negate the favorable properties of the directionally solidified or single-crystal component. [0071] Where the text refers in general terms to directionally solidified microstructures, this is to be understood as meaning both single crystals, which do not have any grain boundaries or at most have small-angle grain boundaries, and columnar crystal structures, which do have grain boundaries running in the longitudinal direction but do not have any transverse grain boundaries. This second form of crystalline structures is also described as directionally solidified microstructures (directionally solidified structures). Processes of this type are known from U.S. Pat. No. 6,024,792 and EP 0 892 090 A1; these documents form part of the disclosure. [0072] The blades or vanes 120 , 130 may likewise have layers protecting against corrosion or oxidation (MCrAlX; M is at least one element selected from the group consisting of iron (Fe), cobalt (Co), nickel (Ni), X is an active element and represents yttrium (Y) and/or silicon and/or at least one rare earth element, or hafnium (Hf)). Alloys of this type are known from EP 0 486 489 B1, EP 0 786 017 B1, EP 0 412 397 B1 or EP 1 306 454 A1, which are intended to form part of the present disclosure. [0073] It is also possible for a thermal barrier coating, consisting for example of ZrO 2 , Y 2 O 4 -ZrO 2 , i.e. unstabilized, partially stabilized or completely stabilized by yttrium oxide and/or calcium oxide and/or magnesium oxide, to be present on the MCrAlX. Columnar grains are produced in the thermal barrier coating by means of suitable coating processes, such as for example electron beam physical vapor deposition (EB-PVD). [0074] Refurbishment means that after they have been used, protective layers may have to be removed from components 120 , 130 (e.g. by sand-blasting). Then, the corrosion and/or oxidation layers and products are removed. If appropriate, cracks in the component 120 , 130 are also repaired. This is followed by recoating of the component 120 , 130 , after which the component 120 , 130 can be reused. [0075] The blade or vane 120 , 130 may be hollow or solid in form. If the blade or vane 120 , 130 is to be cooled, it is hollow and may also have film-cooling holes 418 (indicated by dashed lines).
The invention relates to a material composition that is used for producing a coating for a component, especially a turbine component, which is made of a metallic basic material, i.e. a metal or a metal alloy. Said material composition comprises a matrix material for forming a basic coating matrix and at least one filler for adjusting desired coating proportions or coating characteristics. The matrix material can be provided especially with basic glass ceramic properties. The inventive material composition is characterized in that the matrix material and/or the filler contains nanoparticles
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CROSS-REFERENCE TO RELATED APPLICATIONS This application is a continuation-in-part of U.S. patent application Ser. No. 09/345,929, filed Jul. 1, 1999, in now U.S. Pat. No. 6,351,021, and a conversion of U.S. Ser. No. 60/155,027 filed Sep. 20, 1999. BACKGROUND OF THE INVENTION Advanced wireless communications products demand integrated circuit technologies with high performance, high levels of system integration, low power and low cost. For wireless applications up to several GHz, silicon BiCMOS technology is uniquely suited to meet these requirements. Of critical important to RF design is the availability of high quality passive components. In particular, it is desirable to have implanted thin film resistors that have a low temperature coefficient of resistance. Unfortunately, existing techniques for polysilicon thin film resistors generally result in thin film resistors with relatively large temperature coefficients of resistance. SUMMARY The invention comprises a polysilicon thin film low temperature coefficient resistor and a method for the resistor's fabrication that overcome the coefficient of resistance problem of the prior art, while at the same time eliminating steps from the BiCMOS fabrication process, optimizing bipolar design tradeoffs, and improving passive device isolation. The low temperature coefficient of resistance resistor (TCRL) is formed on a layer of insulation, typically silicon dioxide or silicon nitride. The layer comprises polysilicon that has a relatively high concentration of dopants of one or more species, and has a substantial amount of unannealed implant damage. Contrary to prior art methods, the implanted resistor is annealed less than typical prior art implanted resistors in order to leave some planned unannealed damage in the resistor. The planned damage gives the TCRL a higher resistance without increasing its temperature coefficient. Thus, even though the temperature may increase, the relative value of the resistance remains the same. As such, the resistor is more precise than others produced with current methods, and may be used where precision requirements for high quality RF devices apply. A process for fabrication of the resistor is used which combines separate spacer oxide depositions, provides buried layers having different diffusion coefficients, incorporates dual dielectric trench sidewalls that double as a polish stop, supplies a spacer structure that controls precisely the emitter-base dimension, and integrates bipolar and CMOS devices with negligible compromise to the features of either type. DESCRIPTION OF THE DRAWINGS In order to highlight features of the invention while showing them in their proper context, the proportions shown in the figures are not to scale. FIGS. 1-19 show sequential process steps in the formation of a TCRL in a BiCMOS process FIGS. 20-25 show experimental results for the TCRL. FIG. 26 shows a more-detailed cross-section of the NPN bipolar device formed in the invention's BiCMOS process. FIG. 27 shows one embodiment of the present invention that includes two bipolar devices. DETAILED DESCRIPTION OF THE INVENTION All figures show the lateral division of the regions of the substrate into CMOS regions 100 , bipolar NPN regions 200 , and transition regions 150 between the CMOS and bipolar regions. The regional divisions are shown by dotted lines. Refer first to FIG. 1. A P-type substrate has its upper surface covered with a suitable ion implantation mask such as deposited oxide, thermally-grown oxide or photoresist. Openings are made in the resist mask to define the N+buried layer regions 12 . 1 and 12 . 2 . Those regions are implanted with a first N-type dopant such as Arsenic. The implantation mask is then stripped. The substrate is then covered with a second suitable ion implantation mask such as deposited oxide, thermally-grown oxide or photoresist. Openings are made in the mask to define other buried layer regions 12 . 3 , into which are implanted a second N-type dopant with a significantly different diffusion coefficient than the first. An example of another buried layer region 12 . 3 is illustrated in FIG. 27 . The two different buried layer dopants enable the fabrication of transistors with varying collector profiles, which can be tailored to address speed versus breakdown voltage tradeoffs in the RF devices. Two different collector profiles, coupled with the use of the selectively implanted collector, provide for an integrated circuit with four NPN devices. N+buried layers 12 . 1 and 12 . 2 are driven in with a suitable annealing operation and an N-type epitaxial layer 11 is grown on top of the substrate 10 . As a result, the substrate 10 is patterned into CMOS regions 100 that are separated from bipolar NPN regions 200 by transition regions 150 . The N-type buried layers 12 . 1 and 12 . 2 are formed beneath regions that will receive P-type wells. No buried layer is required for the N-type wells. The initial trench formation step is shown in FIG. 2 . Isolation trenches are formed between transition region 150 and the NPN transistor region as well as in other locations as needed for improved lateral isolation. A trench photoresist mask 20 is uniformly deposited and patterned on the substrate 10 . The photoresist is developed to expose the trench regions 21 . A suitable wet or dry etch operation etches the trenches 21 down to a level below the N+buried layers 12 . 1 and 12 . 2 . The bottoms of the trenches are then implanted with a suitable P+channel stop 22 . As shown in FIG. 3, the next step includes stripping the photoresist 20 , performing thermal oxidation on the trench sidewalls and depositing and patterning a sidewall dielectric layer 23 such as an nitride layer. Oxidation layer 23 is densified, providing a polish stop for planarization. Nitride in this layer has the feature of closely matching the thermal characteristics of silicon. The layer is formed at a thickness which is thin enough to prevent any overhang of the trench cavity, thereby allowing complete trench fill during subsequent deposition steps. Oxidation layer 23 also provides a pad oxide for LOCOS at a later stage. The combination of thermal oxidation, oxide deposition and oxide densification allows the trench sidewall to match the thermal expansion rate of the silicon substrate. An alternate embodiment would be to deposit the sidewall dielectric layer in such away that would cause subsequent trench fill to form a void in the trench which is below the surface of the silicon substrate. This feature provides stress relief and eliminates silicon defect generation in the silicon adjacent the trench. The substrate 10 is then subjected to a polysilicon deposition step that deposits a polysilicon layer 24 over the substrate 10 and epitaxial layer It and fills the trenches 21 . The undoped polysilicon fill is a semi-insulating material, which provides a favorable electrical characteristic for RF parasitic capacitances. FIG. 4 shows completion of the trenches. The substrate 10 and epitaxial layer 11 are planarized to remove the layers of polysilicon 24 and the thermal oxide 23 from the surface of the substrate 10 and epitaxial layer 11 in all areas except above the trenches. Such planarization is accomplished with a conventional chemical mechanical polishing operation. The nitride underneath the polysilicon serves as a hard stop during the polish operation and protects the underlying oxide and silicon from damage. The thinness of the oxide nitride sandwich also assures the precise match of the polished trench polysilicon surface to the original silicon surface. It is important both to protect the trenches 21 and to cover the NPN region 200 during formation of the CMOS devices. Likewise, it is a goal of this process to combine as many of the CMOS and bipolar processing steps as possible. Accordingly, turning to FIG. 5, the trenches are initially protected from the subsequent CMOS processing steps. This protection includes forming a pad oxide layer 51 over the trenches. Pad oxide layer 51 is followed by an N+sinker photoresist deposition, patterning, and implantation step to form the N+sinker 52 for the future collector of the NPN transistors 200 . Next, a layer of silicon nitride 54 is deposited over the pad oxide 51 on the surface of the substrate 10 and epitaxial layer 11 . The silicon nitride is initially patterned to expose local oxidation (LOCOS) regions 50 . Following LOCOS patterning, a conventional LOCOS operation fabricates LOCOS regions 50 that provide surface lateral isolation of the NMOS and PMOS devices 100 and separate the sinker diffusion 52 from the rest of the NPN transistor 200 . The silicon nitride is stripped from the rest of the surface of the substrate 10 and epitaxial layer 11 except for regions above the trenches 21 . During the LOCOS operation, a ‘skin’ layer of silicon dioxide forms on the surface of the nitride oxidation mask. This skin layer is patterned using conventional photoresist and wet etch, leaving the skin layer over the trench regions. After photoresist removal, the nitride is removed in a suitable wet etch chemistry except for regions above the trenches 21 The use of this oxide layer allows simultaneous protection of the trench areas and removal of the nitride in a manner completely benign to the underlying pad ox and silicon substrate regions. Protection of these regions from further stress-generating thermal oxidation is important to the successful fabrication of shallow transistor structures, which follows as taught in U.S. Pat. No. 5,892,264. The pad oxide is then removed from the surface of substrate 10 and epitaxial layer 11 to expose the surface for further fabrication. Refer now to FIG. 6 . In the next step, a sacrificial oxidation is performed on the surface of epitaxial layer 11 . The oxidation is atypical first step in the formation of N-wells and P-wells for the CMOS devices 100 . Suitable photoresist masks and implants 62 provide the N-wells and P-wells for the CMOS devices. A heavier P-type implant 64 provides junction isolation to separate PMOS and NMOS devices. Following removal of the sacrificial oxide, a gate oxide layer 65 , typically a thermal oxide, is grown on the surface of epitaxial layer 11 . That step is followed by uniform deposition of a layer of polysilicon which is subsequently patterned and doped to form polysilicon gates 66 . The next stage in the fabrication of the CMOS transistors is shown in FIG. 7 . Next, the NMOS and PMOS drains receive a typical lightly-doped drain implant 72 (N) or (P) respectively (the P-type implant is not shown here) for forming the N-type lightly-doped drain regions and the P-type lightly-doped drain regions. An annealing step drives the lightly doped drains slightly under the sidewall of the gates. The lightly doped drain regions use the sidewalls of the gate as masks. These regions are self-aligned in a conventional manner using the gate as masks followed by suitable P-type and N-type implants. Following that step, in a region not shown in the figure, a typical P+resistor is formed in the N-type epitaxial region 11 using a suitable photoresist and implant. Next, an NPN protection spacer oxide layer 78 is uniformly deposited over epitaxial layer 11 . The spacer oxide 78 covers the transition region 150 and NPN region 200 of layer 11 . Without this spacer oxide coverage, subsequent CMOS processing steps would interfere with the formation of the NPN transistor. The spacer oxide layer over the gate 66 is patterned and removed to leave sidewall spacers 70 . 1 , 70 . 2 at the edges of the gate 66 . The spacer oxide layer 78 not only provides the sidewall spacers for the CMOS devices but also provides a hard mask and surface isolation for the active elements of the NPN transistor. Performing this deposition step early in the process saves one or more deposition and masking steps later in the process. As a result, the spacer oxide layer 78 forms the mask for the self aligned sources and drains of the CMOS devices and the mask for the collector and emitter openings 126 , 127 , respectively. See FIG. 12 for these later process effects The next CMOS processing step is shown in FIG. 8. A screen oxide layer 80 is deposited and patterned to cover the lightly doped source and drain regions of the CMOS device. Those regions are then suitably implanted with either P+or N+ions to form sources 81 and drains 82 . The respective P-type and N-type sources and drains are then subjected to an annealing operation where the diffusion time is set to adjust the depth of the sources and drains. While the figures show only one MOS device, those skilled in the art understand that the process disclosed herein can be used to form multiple transistors including pluralities of NMOS, PMOS and bipolar devices (see FIG. 27 ). Having completed the formation of the CMOS transistors, the process protects the CMOS transistors while fabricating the NPN transistors. As a first step, a CMOS nitride etch stop protection layer 90 , as shown in FIG. 9, is uniformly deposited over epitaxial layer 11 . On top of the nitride protection layer, there is deposited a CMOS oxide protection layer 92 . Since the two protection layers can be selectively etched with respect to each other, the combination of deposited layers in two sequential steps saves a substantial number of future process steps by using the two layers as different etch stops. A photoresist layer 94 is deposited and patterned to cover the CMOS devices and at least part of the LOCOS region that extends from the transition region 150 into the CMOS region 100 . The CMOS oxide protection layer 92 and nitride protection layer 90 are stripped from the exposed NPN region 200 using suitable wet etchings. As a result of sequential etching operations, the spacer oxide layer 78 is exposed as shown in FIG. 10 . Turning to FIG. 11, a, photoresist layer 110 is uniformly deposited over spacer oxide layer 78 and patterned to have openings 112 and 114 in the NPN section 200 . With the photoresist 110 in place, the spacer oxide in exposed regions 112 and 114 is removed in order to expose the surface of the sinker diffusion 52 and the surface of the subsequent NPN transistor 200 . In the formation of the NPN transistor, the process forms the extrinsic base first, then the intrinsic base, and finally the emitter. The extrinsic base comprises a stack of layers that are deposited on the epitaxial layer 11 Turning to FIG. 12, these layers include a doped polysilicon layer 120 , a tungsten suicide layer 121 , a polysilicon cap layer 122 , an inter-poly oxide layer 123 and a titanium nitride anti-reflective coating 124 . The polysilicon layer 120 , WSi layer 121 and polysilicon cap layer 122 are deposited followed by an implant of boron that will form the doping for the extrinsic base 222 . The polysilicon cap layer is included to prevent the boron doping from segregating heavily at the top of the poly/WSi layer and not adequately diffusing into the silicon to create the extrinsic base. It also prevents unwanted sputtering of the WSi layer during the boron implant, which could potentially contaminate the implant tool with heavy metallics. The stack is suitably patterned to form the emitter opening 127 . As a result of thermal processing, dopants from layer 120 form the extrinsic base 222 . A further boron implant through the emitter opening forms the intrinsic base 220 . With the patterning mask for the stack still in place, a SIC (Selectively Implanted Collector) implant 224 is also made through the intrinsic base 220 and the emitter hole 127 . The stack pattern mask helps mask the high energy SIC implant and creates a perfect self-alignment of the SIC to the transistor. The SIC implant 224 contacts the N+buried layer 12 . 2 . The SIC implant 224 is annealed, the emitter surface is oxidized and a P-type implant completes the intrinsic base 220 . Turning to FIG. 13, a layer of base spacer oxide 130 is deposited to mask the base region. A nitride spacer layer 131 is deposited and etched to open the emitter region. The base spacer oxide is etched with suitable hydrofluoric acid. The structure of the composite spacer allows the emitter-to-extrinsic-base spacing, and hence, speed-versus-breakdown device tradeoffs, to be varied easily by changing the nitride spacer deposition thickness, the base spacer oxide etch time, or both. Next, an emitter polysilicon layer 132 is deposited and patterned to form the emitter contact 134 and the collector contact 133 . In a subsequent annealing operation (see FIG. 17 ), the N-type dopants from the emitter poly layer 132 diffuse into the surface of the epitaxial layer 11 in order to form the collector surface contact and the emitter of the NPN transistors 200 . FIGS. 14 and 15 show the formation of the polysilicon resistor with a relatively low temperature coefficient of resistance (TCRL) resistor 141 . As a first step, a protective oxide 140 is deposited over the emitter polysilicon layer 132 . This layer protects any exposed emitter polysilicon layer 132 from etching when the TCRL regions are defined. A polysilicon layer 142 is deposited in the opening. Next, the polysilicon layer is implanted with a BF 2 implant 143 Finally, the TCRL 141 is covered with a photoresist and etched to its suitable size As shown in FIG. 15, the TCRL layer 141 is then covered with a protective oxide 144 The oxide is suitably patterned and masked to protect the underlying portion of the TCRL 141 , while uncovering the contact regions of the resistor. It will be noted that the TCRL poly layer is deposited late in the process. As such, it is possible to deposit an amorphous silicon film and then adjust its resistivity by adding dopants. This process of the invention forms a TCRL resistor 141 that has a resistance of 750 ohms per square and a temperature coefficient of resistance that is less than 100 parts per million (ppm). The resistor is formed using a non-selective BF 2 implant to dope the polysilicon layer. A 900° C. rapid thermal annealing (RTA) step activates the resistor implant and sets the final doping profiles for the bipolar and MOS devices 200 , 100 . It will be noted that a TCRL poly layer is deposited late in the process. The invention's process deposits an amorphous silicon film and then adjusts its resistivity by adding dopants. A non-selective BF 2 implant is used to dope the film. A mask is used to clear oxide from all contact areas and a 900° C. RTA step activates resistor implants to set the final doping. Resistor contacts are consequently silicided before final back end processing. The TCRL resistor 141 separates the resistance from temperature sensitivity. In the prior art, it was assumed that high resistivity resulted in a greater temperature sensitivity. Antecedents to the inventive process attempted to separate those two characteristics by providing a relatively thin film with dopings adjusted to set the resistivity to 750 ohms per square. As BF 2 implants approach a high level, an unanticipated and counter-intuitive increase in resistance was observed. This behavior was not observed when only boron was used to dope this film. Normal expectations were that higher implant levels would decrease resistance, not increase it It appears that the heavier ion (BF 2 ) in high doses creates a large amount of damage in the polysilicon film and that this damage cannot be annealed at a relatively low temperature (900° C.) with short thermal annealing (RTA) to activate the implants. The implant damage apparently creates additional trapping sites for carriers resulting in increased resistance at higher implant doses. It is believed that co-implantation of other ions could produce similar results making it possible to use the same high dose boron implant to produce even higher value resistors as well as emitters for PNP's or low resistivity extrinsic bases for NPN's or the sources and drains of MOS devices. In our preferred embodiment, the polysilicon layer 142 has a thickness of 70 nm and may be in a range of from 65 nm to 75 nm. The implant concentration of boron ions 142 is 1.3×10 16 and may be in a range from 9×10 15 to 1.5×10 16 . Early in the invention's development, three film thicknesses with a medium boron dose were chosen for evaluation. As shown in table 1, the thinnest film came the closest to the objective of 750 ohms per square. However, the TCRs of all cells were above the goal of 100 ppm. A second set of tests left the film thickness at the thin setting and varied the implant dose over more than one decade with the expectation that the higher doses would result in lower sheet resistances and lower TCRs. TABLE 1 TCR/RS vs. Poly Thickness Poly Th. Rs TCR Thin 650 228 Med. 532 238 Thick 431 292 At first, as indicated in FIG. 20, there was very little change in sheet resistance and TCR with increasing doses. However, as the implant levels started to approach the highest levels, an unanticipated increase in resistance was observed while the TCRs experienced a sharp decline until they became negative at the highest dose. Yamaguchi, et al. [Yamaguchi, et al., “ Process and Device Characterization for a 30 -GHz ft Submicrometer Double Poly-Si Bipolar Technology Using BF 2 -Implanted Base with Rapid Thermal Process ”, IEEE TED, August 1993.] observed the same relationship between TCR and sheet resistance. In this study, TCRs of boron-doped P-type polysilicon resistors fabricated with a 150 nm amorphous layer approach zero at sheet resistances of 600-800 ohms per square. However, within the range of doses in the cited investigation, resistance declines with increasing boron doses. In a parallel experiment aimed at lowering TCR, boron and boron plus another species (BF 2 ) were implanted into a medium thickness film. The implant energies were adjusted to compensate for the different ranges of the species The results, once again, were quite unexpected: the average resistance of the boron by itself was 200 ohms per square with a TCR of 445 ppm while the values for the BF 2 resistors were 525 and 221 respectively Based on these results, it is believed that the heavier ion and the extremely high doses create a large amount of damage in the polysilicon film which cannot be annealed by the relatively short 900° C. RTA. This damage creates additional trapping sites for the carriers resulting in increased resistance at higher implant doses. Therefore, it is believed that co-implantation of other ions could produce similar results thus making it possible to use the same high dose boron implant to produce high value resistors as well as the emitters for PNPs or low resistivity extrinsic bases for NPNs or the sources and drains of MOS devices Table 2 shows the effects of RTA temperature on sheet resistance and TCR as a function of implant dose. Once again, the higher sheet resistances obtained with the lower temperature yield reduced TCRs except at the lower dose where a resistance of 763 results in a TCR of 168 . This lends support to the theory that damage is a major part of the previously observed TCR behavior. The lower RTA temperature leads to suppressed carrier activation and higher sheets. Concurrently, there is less annealing of the implant damage. However, at the low dose, there is insufficient implant damage to degrade carrier mobility to the point where it becomes less sensitive to the temperature variations. TABLE 2 TCR/RS vs. RTA Temp Dose Rs TCR RTA Low 637 293 900 C. Low 763 168 800 C. Med. 628 271 900 C. Med. 849 76 800 C. High 726 90 900 C. High 832 22 800 C. Characterization Results FIG. 21 is a scatter plot of a 30×30 micron resistor showing the relationship of TCR to sheet resistance at 50° C. was chosen as the lowest measurement point The TCR is calculated by fitting a line to values measured from 50-125° C. at 25° intervals The dashed lines denote the objectives that were set for this development project. Parts from two different runs were packaged and measured from −50 to 150° C. FIG. 22 shows average changes in sheet resistance for nine parts measured over this temperature range while FIG. 23 is a plot of the calculated TCRs for this set of measurements. The solid line represents a linear fit while the dashed line is a polynomial fit. The upward “hook” observed at lower temperature is typical to that of diffused resistors. Since matching is of particular interest to analog and mixed signal designers, FIG. 24 shows the percent mismatch as a function of length for a fixed width resistor and FIG. 25 represents the same parameter as a function of width with a fixed length. The data, as expected, show improved matching with increasing dimensions. The feasibility of fabricating a high value polysilicon resistor with low TCR has been demonstrated. The investigation has uncovered a relationship between ion species, sheet resistance and TCR which can result in reduced process complexity. Since 800° C. RTA is a benign temperature for present bipolar processes, it is possible if desired to de-couplet he resistor activation step from the RTA used to set the device electrical parameters. With the Bipolar and TCRL components processed to this point, it is now appropriate to remove the protection layers from the CMOS portions of the wafer so that the remaining metalization operations can be performed on all devices. Turning next to FIG. 16, the TCRL resistor 141 and the NPN transistor regions 200 are protected with a layer of photoresist 160 . The photoresist is patterned to open a region above the CMOS devices 100 . Next, the protective oxide 92 (FIG. 15) is removed. Now refer to FIG. 17 . The photoresist layer 160 is removed, followed by removal of the nitride protect layer 90 . At this time, the emitter 170 and the resistor 141 are subjected to an RTA step. The step is carried out at approximately 900° C. for 0.5 minutes, and completes the fabrication of the emitter first prepared in the steps shown previously in FIG. 13 The screen oxide layer 80 over the lightly doped source and drain regions of the CMOS device is then removed. As shown in FIG. 18, the exposed polysilicon regions of the resistor 141 , the gate 66 , the source and drain regions, and the collector and emitter contacts 133 , 134 are silicided with platinum 180 to form a platinum silicide layer on the exposed polysilicon. As shown in FIG. 19, a sidewall spacer oxide 190 is applied to the sidewalls of the emitter contact 134 and the collector contact 133 The rest of the spacer oxide is etched and removed. Thereafter, the substrate is subjected to suitable metallization layers, including the formation of three metal layers separated from each other by suitable insulating layers and separate layers being selectively interconnected, one to the other, by the formation of vias that are filled with conductive material. After metallization the entire device is covered with a passivation layer, typically silicon nitride, and a substrate including the integrated circuits and devices made thereon are then further processed for testing and assembly. Having thus disclosed preferred embodiments of the invention, those skilled in the art will appreciate that further modifications, changes, additions and deletions may be made to that embodiment without departing from the spirit and scope of the appended claims.
A low temperature coefficient resistor (TCRL) has some unrepaired ion implant damage. The damaged portion raises the resistance and renders the resistor less sensitive to operating temperature fluctuations A polysilicon thin film low temperature coefficient resistor and a method for the resistor's fabrication overcomes the coefficient of resistance problem of the prior art, while at the same time eliminating steps from the BiCMOS fabrication process, optimizing bipolar design tradeoffs, and improving passive device isolation. A low temperature coefficient of resistance resistor (TCRL) is formed on a layer of insulation, typically silicon dioxide or silicon nitride, the layer comprising polysilicon having a relatively high concentration of dopants of one or more species. An annealing process is used for the implanted resistor which is shorter than that for typical prior art implanted resistors, leaving some intentional unannealed damage in the resistor. The planned damage gives the TCRL a higher resistance without increasing its temperature coefficient. A process for fabrication of the resistor is used which combines separate spacer oxide depositions, provides buried layers having different diffusion coefficients, incorporates dual dielectric trench sidewalls that double as a polish stop, supplies a spacer structure that controls precisely the emitter-base dimension, and integrates bipolar and CMOS devices with negligible compromise to the features of either type.
7
FIELD OF THE INVENTION The invention refers to an analogue amplifier to increase circuit testability by featuring additional multiplexing capability. DESCRIPTION OF PRIOR ART Any procedure carried out upon an integrated circuit intended to establish its quality, performance or reliability is commonly called testing. Testing can be carried out at different stages during the development of an integrated circuit; different procedures are followed, according to particular goals and circuit type, for each development stage. The degree to which an integrated circuit facilitates the establishment of test criteria and the performance of tests to determine whether those criteria have been met is commonly referred as testability. According to existing literature, integrated circuits testability can be quantified by means of existing capacity to control and or to observe voltages on relevant nodes in the integrated circuit. These magnitudes are commonly referred as controllability and observability. The twin requirements of high precision and accuracy in signal measurement are superimposed to those basic requirements of controllability and observability to establish proper test criteria for modern high-speed communication circuits. On the other hand, new technologies make more and more defects to be non-visible, new failure mechanisms emerge and a relevant number of circuit features are unsimulatable. As a consequence, test cost and complexity increases, but also a higher risk exist to produce delays in bringing products to market or just to suffer from yield detractors that lead to higher manufacturing cost. Setting up design procedures that include some constrains to increase circuit testability is a common approach to address that problem. Testability can be improved either by increasing the controllability or the observability of some internal nodes. Identifying a testability issue, and therefore choosing proper nodes upon which to act in order to improve their observability or their controllability is most of the times an ad hoc issue. Conventional approach to raise up internal nodes controllability or observability uses multiplexors to provide alternative signal paths. However, because of the ad-hoc nature of the task, top level floor plan layout constrains may lead to situations where it is not possible to include new multiplexor blocks in the original design without severe impact upon schedule because of the re-design effort due. FIG. 1 shows a not accessible node in the signal path which is driven by an analogue amplifier. To test such a not accessible node a design for test solution according to the state of the art is shown in FIG. 2 . For access to the node a multiplexor is provided so that a test signal can be applied directly to the node (e.g. from an external signal generator). The multiplexor is controlled by a mode control signal which switches between a test signal T and the amplified normal signals S of the signal path. All signals are differential signals. The drawback of a multiplexor-based solution is that the load capacitance is increased. Further providing a multiplexor increases the necessary area on the chip such increasing production costs. A further drawback is that because of the additional multiplexor the power consumption is increased. SUMMARY OF THE INVENTION Accordingly it is the object of the present invention to provide means which allow a better testability by increasing internal controllability. Further advantages of the present invention are that the redesign effort is minimal, that the silicon area overhead is minimal and that the increase of the power supply current consumption is minimal. The basic idea of the present invention is that in the main signal propagation path of analogue integrated circuits a number of amplifiers are provided to drive proper internal nodes in order and to guarantee the required signal to noise ratio. Whenever a controllability issue is detected the design of some amplifier is modified to include multiplexing capabilities that allow injecting test signals within the main signal propagation path with minimal redesign effort and minimal impact upon normal operation mode of the required amplification function. In accordance with one aspect, the invention provides an analogue amplifier with multiplexing capability comprising an input port, a test input port, an output port, a control input to switch the amplifier between a normal amplifying mode and a test mode, wherein a analogue signal introduced to the input port is amplified to the output port in normal mode, and a test signal on the test port is routed to the output port when the amplifier is in test mode. The test signal is generated in a first embodiment by a built in test pattern generator. The test signal is applied in an alternative embodiment via a pad from an external test pattern generator. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows the signal path in an analogue circuit according to the state of the art; FIG. 2 shows a conventional approach to increase the controllability of an internal node non accessible from any primary input/output of the circuit under test. FIG. 3 shows a pll circuit with added multiplexor according to the state of the art to increase controllability by bypassing the amplified VCO output. FIG. 4 shows a fully differential amplifier, tail current and bias generation according to the state of the art; FIG. 5 shows an arrangement comprising an amplifier according to the present invention in order to increase the controllability of the circuit node driven by said amplifier; FIG. 6 shows a preferred embodiment of the analogue amplifier according to the present invention; FIG. 7 b shows a differential output voltage from an amplifier according to the state of the art as shown in FIG. 4 and FIG. 7 a shows a differential output voltage from an ADfT-analogue amplifier according to the present invention as shown in FIG. 6 ; FIG. 8 shows the spectral content of the output voltages of a conventional amplifier and of the analogue amplifier according to the present invention; FIG. 9 shows noise figure curves of a conventional amplifier and of the analogue amplifier according to the present invention; FIG. 10 shows the 1 dB compression point of the conventional amplifier according to the state of the art; FIG. 11 shows the 1 dB compression point of the analogue amplifier according to the present invention; FIG. 12 shows the IP3 (3 rd order intersection point) for the conventional amplifier; FIG. 13 shows the IP3 for the amplifier according to the present invention. DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 3 shows a conventional approach for testing a phase locked loop, (pLL), circuit within mixed signal circuits. A phase locked loop is a system with induced feedback to maintain an output signal in a specific phase relationship with a reference signal. The pll-circuit shown in FIG. 3 comprises of phase frequency detector PFD controlling a charge pump CP which supplies a deviation signal to the low pass filter LP. The filtered signal is supplied to a voltage controlled oscillator VCO. The voltage controlled oscillator VCO is a circuit that produces an AC-output signal whose frequency is proportional to the input control voltage. The VCO output signal is amplified by a conventional amplifier as shown in FIG. 4 . For test purposes a multiplexor is provided at the output of the amplifier in the conventional approach as shown in FIG. 3 . In the feedback loop a division circuit is provided which produces an output signal whose frequency is an integer division of the input signal frequency. The VCO signal is fed back within the pLL-circuit through a high speed 1/N frequency divider. The proper operation of these frequency divider is essential to guarantee a good pLL-performance. By providing a multiplexor to the output of amplifier A the load capacitance, the area overhead and the power supply consumption are increased. FIG. 4 shows a conventional state of the art differential amplifier A. The amplifier A is connected to a biasing circuit. The conventional amplifier A as shown in FIG. 4 comprises two input terminals and two output terminals. The input terminals are connected to the gate terminals of amplifying MOS-transistors T a . The source nodes of the amplifying transistors T a are connected at a common node to a tail current sink implemented by transistor T b having a gate which is biased by a reference voltage. The drain terminals of the amplifying transistors T a are connected via resistors to a positive supply voltage VDD. According to the present invention the design of the conventional amplifier A as drawn in FIG. 4 is modified to increase the controllability of an internal node driven by said amplifier. Thus the testability of the circuit under test including said amplifier is increased too. FIG. 5 shows a block diagram of an analogue amplifier 1 according to the present invention. The analogue amplifier 1 according to the present invention as shown in FIG. 5 can be switched via a control mode signal between a first normal amplifying mode and a second test mode. A control mode signal is used to switch between both modes. The signal generator can be located externally or be built in. The function of the amplifier 1 in the normal mode can be described as: Z ( S,T )= K 1 ×S+K 2 ×T wherein S is the signal of the signal path, T is the test signal and K 1 , K 2 are constants. Since the function of the conventional amplifier to be modified can be described as: Z ( S )= K 1 ×S the first constant K 1 of the modified amplifier according to the invention is as close as possible to the original amplifying constant K 1 of the conventional amplifier. In the normal test node the constant K 2 of the analogue amplifier 1 according to the present invention is as small as possible (K 2 →0). When the analogue amplifier 1 according to the present invention is switched to the test mode its operation can be described as: Z ( S,T )= K 3 ×S+K 4 ×T In an ideal implementation of the differential amplifier 1 according to the present invention, the constant K 3 is zero to isolate the signal S of the signal path from the injected test signal T. The constant K 4 is close to or lower than one in an ideal implementation (K 3 =0; K 4 ≦1). FIG. 6 shows a circuit diagram of a preferred embodiment of a differential analogue amplifier 1 according to the present invention. The analogue amplifier 1 is fully differential. The differential analogue amplifier 1 comprises an input port 2 - 1 , 2 - 2 for receiving an analogue signal S. The amplifier 1 further comprises a test input port 3 - 1 , 3 - 2 for receiving a test signal T. Further a control input port 4 is provided for receiving a test control signal switching the amplifier 1 between a normal amplifying mode and a test mode. In the normal amplifying mode the amplifier 1 as shown in FIG. 6 amplifies the analogue signal S and transmits the amplified signal via an output port 5 - 1 , 5 - 2 to an internal node within the integrated circuit. In the test mode the test signal T is transmitted to that internal node. The amplifier 1 comprises an amplifying transistor 6 - 1 , 6 - 2 having a gate terminal 7 - 1 , 7 - 2 , a source terminal 8 - 1 , 8 - 2 and a drain terminal 9 - 1 , 9 - 2 . The gate terminals 7 - 1 , 7 - 2 of the amplifying transistors 6 - 1 , 6 - 2 are connected via lines 10 - 1 , 10 - 2 and first switches 11 - 1 , 11 - 2 to the signal input terminals 2 - 1 , 2 - 2 . The drain terminals 9 - 1 , 9 - 2 of the amplifying transistors 6 - 1 , 6 - 2 are connected via lines 13 - 1 , 13 - 2 to the output port 5 - 1 , 5 - 2 of the amplifier 1 . Connected to lines 13 - 1 , 13 - 2 are resistors 14 - 1 , 14 - 2 . The source terminals 8 - 1 , 8 - 2 of the amplifying transistors 6 - 1 , 6 - 2 are connected via a line 15 to a drain terminal 16 of a tail current sink comprising a transistor 17 having a source terminal 18 connected to a second negative supply voltage V ss . The current tail transistor 17 comprises a gate 20 connected via a line 21 and via a second switch 22 to a biasing reference voltage supplied to a terminal 23 of the amplifier 1 . Line 21 further connects gate 20 of current tail transistor 17 to a drain terminal of a switching transistor 24 .The gate 20 of the tail current transistor 17 can be switched by the third switch 24 to the negative supply voltage V SS . The load devices 14 - 1 , 14 - 2 connected to the amplifying transistor 6 - 1 , 6 - 2 are connected via lines 26 - 1 , 26 - 2 and fourth switches 27 - 1 , 27 - 2 to a positive supply voltage. The load devices 14 - 1 , 14 - 2 a further connected via fifth switches 28 - 1 , 28 - 2 to the test signal input port. All switches 11 - 1 , 11 - 2 , 22 , 24 , 27 - 1 , 27 - 2 , 28 - 1 , 28 - 2 of the amplifier 1 are controlled by a test control mode signal applied to the amplifier by terminal 4 . Two inverter circuits 29 - 1 , 29 - 2 invert the test control mode signal, wherein the inverter circuit 29 - 1 supplies the signal not (T-CTRL) to switches 28 - 1 , 28 - 2 , and to switch 22 , and wherein inverter circuit 29 - 2 supplies the signal T-CTRL to switches 11 - 1 , 11 - 2 , switch 24 and switches 27 - 1 and 27 - 2 . The following table shows the states of the switches within the amplifier 1 drawn in FIG. 6 according to the present invention. switch test mode normal mode S 28-1 , S 28-2 On Off S 27-1 , S 27-2 Off On S 11-1 , S 11-2 Off On S 22 Off On S 24 On off In the normal amplifying mode switch 24 and switch 28 - 1 , 28 - 2 are switched off and switches 27 - 1 , 27 - 2 , 11 - 1 , 11 - 2 , 22 are switched on. By means of the switch 28 - 1 , 28 - 2 the test signal is cut off from the output terminal 5 of the amplifier 1 . The gate 7 - 1 , 7 - 2 of the amplifying transistor 6 - 1 , 6 - 2 receives the analogue signal via a switch 11 - 11 , 11 - 2 and transmits the amplified signals to output port 5 - 1 , 5 - 2 of the amplifier 1 . In the normal amplifying mode the gate 20 of the tail current transistor 17 receives the biasing reference voltage via closed switch 22 . Since switch 27 is also closed in the normal amplifying mode the amplifying transistor 6 receives the positive supply voltage V DD via the loading resistors 14 - 1 , 14 - 2 . When switched to the test mode switches 28 - 1 and 28 - 2 , and switch 24 are closed. At the same time switches 27 - 1 , 27 - 2 , 11 - 1 , 11 - 2 and 22 are opened. While switching off switch 27 the amplifying transistor 6 is disconnected from the positive supply voltage V DD and cut off. By opening switch 11 - 1 , 11 - 2 no input signal is supplied to the gate 7 - 1 , 7 - 2 of the amplifying transistor 6 - 1 , 6 - 2 . By isolating gates of the amplifying transistors 6 - 1 , 6 - 2 from the input signal via switches 11 - 1 , 11 - 2 the signal S is isolated from the output port 5 - 1 , 5 - 2 . This ensures that the test signal T supplied to the output port 5 - 1 , 5 - 2 via the load resistors 14 - 1 , 14 - 2 is not affected by spurious signals coming from the input terminals 2 - 1 , 2 - 2 . By switching off switch 22 the transistor 17 does not get a biasing reference voltage. Furthermore its gate 20 is switched to the negative supply voltage V SS by closing switch 24 . In this manner the transistor 17 is cut off completely and the tail current going to ground is nullified. The amplifier design as shown in FIG. 6 focus on the tail current sink and loads of the amplifier 1 which are modified by the switches to reconfigure the operation of the amplifier. The design of a conventional amplifier is modified by adding switches that disconnect the amplifying transistor from the incoming signal and the tail current sink transistor from the bias circuitry. The design is modified in such a way that the injection of the test signal T in the signal path has a minimal impact upon the circuit normal operation. FIGS. 7–12 come from simulation analysis carried out at the operational frequency of 1.6 GHz. FIG. 7 a , 7 b show the differential output wave forms of an original differential amplifier as shown in FIG. 4 in comparison to the differential output of the amplifier 1 according to the present invention as shown in FIG. 6 . The input signal used is a monotonic sinusoidal at 1,562 GHz. FIG. 8 shows the spectral content of the output voltages of the conventional amplifier (a) shown in FIG. 4 and the amplifier (b) according to the present invention as shown in FIG. 6 . The increase of the noise figure at the operation frequency is due mainly to the drop in conversion gain related to the attenuation effect of transistors 11 - 1 and 11 - 2 . The second largest contribution to the relative increase in the noise figure at the operation frequency is coming from transistor switches 27 - 1 , 27 - 2 accounting to less than a quarter of the contribution of transistor switches 11 - 1 , 11 - 2 . FIG. 9 shows the plot of noise figures with a measurement mark at a operating frequency (conventional amplifier a; amplifier according to the present invention b). FIGS. 10 to 13 show different plots of measuring inter-modulation distortion products. The performance of the amplifier according to the present invention it is about 1.5 to 2 dBm better than the original amplifier according to the state of the art. Parasitic capacitance to ground together with the on resistance in transistors 11 - 1 , 11 - 2 implement a low past filter at the inputs 2 - 1 , 2 - 2 of the differential amplifier in the modified circuit. The attenuation provided by this filter at the operating frequency which accounts for the gain drop depicted in FIG. 7 is also responsible for the improvement observed in the circuit linearity. Since the filter attenuation reduces the input power to the differential amplifier it behaves better in terms of intermodulation distortion. Area overhead due to the amplifier design according to the invention accounts for about 9% of the original area due to the original amplifier design. This figure expressed in terms of a total pLL-area, where the amplifier is located, represents about only 0.023% since the amplifier itself takes only about 0.25% of the total pLL-area. In the test mode a low impedance propagation path exist between the test port 3 - 1 , 3 - 2 and the corresponding circuit output nodes 5 - 1 , 5 - 2 , respectively. Transistors 28 - 1 , 28 - 2 used to disconnect the test ports 3 - 1 , 3 - 2 are dimensioned according to the impedance requirements. These elements are placed in series with the loading resistors. According to the present invention a device under test can be reconfigured and its outputs multiplexed to inject test signals. Consequently it is possible to increase the controllability of relevant nodes of the circuit under test, and therefore is testability is also enhanced. The present invention can be adapted to different operating frequencies, ranging from DC to frequencies in the order of tens of GHZ typically used in optical communication circuits. The present invention is applicable to any analogue circuit whose controllability is to be increased. The modification of the design of a conventional amplifier makes possible to inject a test signal (T) with a minimum impact upon the circuit performances. Further the area overhead due to the circuit modification remains below 10% of that of the differential amplifier. While this invention has been described in terms of several preferred embodiments, there are alterations, permutations, and equivalents which fall within the scope of this invention. It should also be noted that there are many alternative ways of implementing the methods and compositions of the present invention. It is therefore intended that the following appended claims be interpreted as including all such alterations, permutations, and equivalents as fall within the true spirit and scope of the present invention.
An analogue amplifier with multiplexing capability, without the need to incorporate a multiplexor, comprising an input port, a test input port, an output port, a control input to switch the amplifier between a normal amplifying mode and a test mode, wherein a analogue signal introduced to the input port is amplified to the output port in normal mode, and a test signal on the test port is routed to the output port when the amplifier is in test mode.
7
BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to an electronic toll collection system (an ETC system) for a toll road. 2. Description of the Related Art In an ETC system for a toll road, when every ETC vehicle passes through a tollgate, an accounting machine in the tollgate and the ETC vehicle communicate with each other by wireless to automatically implement an accounting process. Accordingly, it is unnecessary for the ETC vehicle to pause at the tollgate to pay toll. The ETC vehicle means a vehicle designed for the ETC system. The ETC system can not automatically implement an accounting process with respect to a non-ETC vehicle. The non-ETC vehicle means a vehicle not adapted to the ETC system. It is necessary for the tollgate in the ETC system to discriminate non-ETC vehicles from ETC vehicles, and to guide the non-ETC vehicles to a booth where toll can be manually paid. It is desirable to provide a high accuracy of discrimination of non-ETC vehicles from ETC vehicles. SUMMARY OF THE INVENTION It is an object of this invention to provide an electronic toll collection system (an ETC system) for a toll road which is able to accurately discriminate non-ETC vehicles from ETC vehicles. A first aspect of this invention provides an ETC system comprising an antenna having a predetermined directivity for providing a limited radio-communication service zone; a vehicle sensor for detecting a vehicle which reaches a predetermined position in the limited radio-communication service zone; first means for transmitting a radio signal via the antenna; second means for deciding whether or not a radio response to the radio signal is received via the antenna; third means for, in cases where the second means decides that a radio response to the radio signal is received, judging that there is an ETC vehicle incoming; and fourth means for, in cases where the vehicle sensor detects a vehicle while the second means decides that a radio response to the radio signal is not received, judging that there is a non-ETC vehicle incoming. A second aspect of this invention is based on the first aspect thereof, and provides an ETC system wherein the first means comprises means for continuously transmitting the radio signal via the antenna. A third aspect of this invention is based on the first aspect thereof, and provides an ETC system wherein the limited radio-communication service zone has a length greater than a length of a standard vehicle and smaller than twice the length of the standard vehicle. A fourth aspect of this invention is based on the first aspect thereof, and provides an ETC system wherein the limited radio-communication service zone has a length of about 6.5 m along a lane. A fifth aspect of this invention is based on the first aspect thereof, and provides an ETC system wherein the vehicle sensor is only one in the ETC system. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a tollgate in a background-art ETC system for a toll road which is not prior art against this invention. FIG. 2 is a diagrammatic side view of the tollgate in FIG. 1 . FIG. 3 is a plan view of the tollgate in FIG. 1 . FIG. 4 is a block diagram of an electronic portion of the background-art ETC system in FIG. 1 . FIG. 5 is a diagrammatic side view of a tollgate in an ETC system according to an embodiment of this invention. FIG. 6 is a plan view of the tollgate in FIG. 5 . FIG. 7 is a block diagram of an electronic portion of the ETC system in FIG. 5 . FIG. 8 is a plan view of an antenna in FIG. 5 . FIG. 9 is a flowchart of a segment of a control program for a computer in FIG. 7 . DESCRIPTION OF THE PREFERRED EMBODIMENT A background-art ETC system for a toll road will be explained below for a better understanding of this invention. FIGS. 1 , 2 , and 3 show a tollgate in a background-art ETC system for a toll road which is not prior art against this invention. As shown in FIGS. 1 , 2 , and 3 , the tollgate includes a first vehicle sensor 91 composed of a photo-transmitter 91 A and a photo-receiver 91 B, and a second vehicle sensor 92 composed of a photo-transmitter 92 A and a photo-receiver 92 B. The photo-transmitter 91 A and the photo-receiver 91 B in the first vehicle sensor 91 are located at the opposite sides of a lane, respectively. The photo-transmitter 91 A emits a light beam toward the photo-receiver 91 B along an optical path perpendicular to the lane. The light beam does not reach the photo-receiver 91 B when a vehicle 95 blocks the optical path. The light beam reaches the photo-receiver 91 B in the absence of a vehicle 95 from the optical path. The photo-receiver 91 B converts the presence and the absence of the received light beam into an electric signal representing whether or not a vehicle 95 is in a lane position corresponding to the position of the first vehicle sensor 91 . The photo-receiver 91 B outputs the electric signal as an output signal of the first vehicle sensor 91 . Similarly, the photo-transmitter 92 A and the photo-receiver 92 B in the second vehicle sensor 92 are located at the opposite sides of the lane, respectively. The second vehicle sensor 92 generates and outputs an electric signal representing whether or not a vehicle 95 is in a lane position corresponding to the position of the second vehicle sensor 92 . The position of the second vehicle sensor 92 relative to the lane precedes the position of the first vehicle sensor 91 by an interval of about 4 m. As shown in FIGS. 1 , 2 , and 3 , the tollgate in the background-art ETC system includes an antenna 93 located above the lane. The tollgate also includes a machine box 94 located at one side of the lane. As shown in FIG. 4 , the background-art ETC system has a computer 94 A contained in the machine box 94 (see FIG. 1 ). The computer 94 A is electrically connected to the first vehicle sensor 91 and the second vehicle sensor 92 . In addition, the computer 94 A is connected to a radio transceiver 93 A. The radio transceiver 93 A is connected to the antenna 93 . The computer 94 A includes a combination of an input/output port, a CPU, a ROM, and a RAM. The computer 94 A operates in accordance with a control program stored in the ROM. The radio transceiver 93 A is controlled by the computer 94 A, feeding a radio signal to the antenna 93 . The antenna 93 radiates the radio signal toward the lane as a downward radio signal. Every ETC vehicle has an on-vehicle machine including a combination of an antenna and a radio transceiver. The on-vehicle machine can receive the downward radio signal. The on-vehicle machine can transmit an upward radio signal. The upward radio signal is received by the antenna 93 . The received radio signal is fed from the antenna 93 to the radio transceiver 93 A. The control program for the computer 94 A has a segment which is executed for every incoming vehicle. Specifically, a step “ 1 ” in the program segment decides whether or not a vehicle reaches the lane position of the first vehicle sensor 91 by referring to the output signal therefrom. When a vehicle reaches the lane position of the first vehicle sensor 91 , the program advances from the step “ 1 ” to a step “ 2 ”. Otherwise, the step “ 1 ” is repeated. The step “ 2 ” controls the radio transceiver 93 A to start radio communication with the incoming vehicle. Specifically, the radio transceiver 93 A outputs a radio signal to the antenna 93 . The radio signal is radiated from the antenna 93 as a downward radio signal. In the case where the incoming vehicle is an ETC vehicle, the on-vehicle machine of the incoming vehicle receives the downward radio signal and transmits an upward radio signal in response to the received downward radio signal. The upward radio signal is a response to the downward radio signal. The upward radio signal contains ID (identification) information, departure-place information, and information of places through which the vehicle passed. The upward radio signal is received by the antenna 93 . The received radio signal is fed from the antenna 93 to the radio transceiver 93 A. The radio transceiver 93 A extracts the information from the received radio signal. The radio transceiver 93 A outputs the extracted information to the computer 94 A. In this case, the computer 94 A is notified that a response to the downward radio signal has successfully come from the incoming vehicle. On the other hand, in the case where the incoming vehicle is a non-ETC vehicle, any upward radio signal is not received by the antenna 93 and hence the radio transceiver 93 A informs the computer 94 A that a response to the downward radio signal has failed to come from the incoming vehicle. A step “ 3 ” following the step “ 2 ” decides whether or not a response to the downward radio signal has successfully come from the incoming vehicle by referring to the information given by the radio transceiver 93 A. When a response to the downward radio signal has successfully come from the incoming vehicle, the computer 94 A judges the incoming vehicle to be an ETC vehicle. In this case, the program advances from the step “ 3 ” to a step “ 4 ”. When a response to the downward radio signal has failed to come from the incoming vehicle, the computer 94 A judges the incoming vehicle to be a non-ETC vehicle. In this case, the program advances from the step “ 3 ” to a step “ 6 ”. The step “ 4 ” implements an accounting process related to the incoming vehicle. A step “ 5 ” following the step “ 4 ” decides whether or not the incoming vehicle reaches the lane position of the second vehicle sensor 92 by referring to the output signal therefrom. When the incoming vehicle reaches the lane position of the second vehicle sensor 92 , the program advances from the step “ 5 ” to a step “ 8 ”. Otherwise, the step “ 5 ” is repeated. Similarly, the step “ 6 ” decides whether or not the incoming vehicle reaches the lane position of the second vehicle sensor 92 by referring to the output signal therefrom. When the incoming vehicle reaches the lane position of the second vehicle sensor 92 , the program advances from the step “ 6 ” to a step “ 7 ”. Otherwise, the step “ 6 ” is repeated. The step “ 7 ” controls a suitable apparatus (not shown) to guide the incoming vehicle to a tollbooth and to instruct the incoming vehicle to pause at the tollbooth for manually paying toll. After the step “ 7 ”, the program advances to the step “ 8 ”. The step “ 8 ” controls the radio transceiver 93 A to terminate radio communication with the incoming vehicle. After the step “ 8 ”, the program returns to the step “ 1 ”. As best shown in FIG. 2 , the tollgate of the background-art ETC system has a predetermined radio-communication service zone 97 spreading from the antenna 93 to the surface of the lane. Within the predetermined service zone 97 , the intensity of a downward radio signal which has been radiated from the antenna 93 is equal to or greater than a rating level, for example, −60 dBm. When an ETC vehicle is in the predetermined service zone 97 , radio access thereto (radio communication therewith) can be executed. The predetermined service zone 97 is designed to just cover the region of the lane between the position of the first vehicle sensor 91 and the position of the second vehicle sensor 92 . Specifically, the predetermined service zone 97 extends from a place following the position of the first vehicle sensor 91 by an interval of 2 m to a place substantially coincident with the position of the second vehicle sensor 92 . The predetermined service zone 97 is surrounded by a zone 98 forming a pseudo service zone. Within the pseudo service zone 98 , the intensity of a downward radio signal is equal to or greater than a certain level, for example, −70 dBm at which radio communication with an ETC vehicle may be established. For example, the pseudo service zone 98 extends from a place following the position of the first vehicle sensor 91 by an interval of 5 m to a place preceding the position of the second vehicle sensor 92 by an interval of 1 m. The background-art ETC system tends to erroneously judge a non-ETC vehicle to be an ETC vehicle in conditions mentioned below. When a non-ETC vehicle (a first incoming vehicle) immediately followed by an ETC vehicle (a second incoming vehicle) reaches the lane position of the first vehicle sensor 91 , a downward radio signal is radiated from the antenna 93 . In the case where the ETC vehicle (the second incoming vehicle) has already reached the pseudo service zone 98 at this moment, the ETC vehicle may respond to the downward radio signal while the non-ETC vehicle (the first incoming vehicle) does not respond thereto. The computer 94 A is caused by the response from the second incoming vehicle to erroneously judge the first incoming vehicle to be an ETC vehicle. EMBODIMENT FIGS. 5 and 6 show a tollgate in an ETC system for a toll road according to an embodiment of this invention. As shown in FIGS. 5 and 6 , the tollgate includes a vehicle sensor 11 of an optical type. The vehicle sensor 11 is composed of a photo-transmitter 11 A and a photo-receiver 11 B. The photo-transmitter 11 A and the photo-receiver 11 B are located at the opposite sides of a lane, respectively. The photo-transmitter 11 A emits a light beam toward the photo-receiver 11 B along an optical path perpendicular to the lane. The light beam does not reach the photo-receiver 11 B when a vehicle 14 blocks the optical path. The light beam reaches the photo-receiver 11 B in the absence of a vehicle 14 from the optical path. The photo-receiver 11 B converts the presence and the absence of the received light beam into an electric signal representing whether or not a vehicle 14 is in a lane position corresponding to the position of the vehicle sensor 11 . The photo-receiver 11 B outputs the electric signal as an output signal of the vehicle sensor 11 . As shown in FIGS. 5 and 6 , the tollgate includes an antenna 13 located above the lane. Specifically, the antenna 13 is directly above a position on the lane which precedes the position of the vehicle sensor 11 by a predetermined interval, for example, about 1 m. The tollgate also includes a machine box 12 located at one side of the lane. As shown in FIG. 7 , the ETC system has a computer 12 A contained in the machine box 12 (see FIG. 5 ). The computer 12 A is electrically connected to the vehicle sensor 11 . In addition, the computer 12 A is connected to a radio transceiver 13 A. The radio transceiver 13 A is connected to the antenna 13 . The computer 12 A is connected to a suitable apparatus (a guiding apparatus) 19 designed to guide an incoming vehicle to a tollbooth and to instruct the incoming vehicle to pause at the tollbooth for manually paying toll. The computer 12 A includes a combination of an input/output port, a CPU, a ROM, and a RAM. The computer 12 A operates in accordance with a control program stored in the ROM. The radio transceiver 13 A is controlled by the computer 12 A, feeding a radio signal to the antenna 13 . The antenna 13 radiates the radio signal toward the lane as a downward radio signal. Every ETC vehicle has an on-vehicle machine including a combination of an antenna and a radio transceiver. The on-vehicle machine can receive the downward radio signal. The on-vehicle machine can transmit an upward radio signal. The upward radio signal is received by the antenna 13 . The received radio signal is fed from the antenna 13 to the radio transceiver 13 A. As shown in FIG. 5 , the tollgate of the ETC system has a predetermined radio-communication service zone 17 spreading from the antenna 13 to the surface of the lane. Within the predetermined service zone 17 , the intensity of a downward radio signal which has been radiated from the antenna 13 is equal to or greater than a rating level, for example, −60 dBm. When an ETC vehicle is in the predetermined service zone 17 , radio access thereto (radio communication therewith) can be executed. The predetermined service zone 17 is designed to extend in a given region of the lane which contains the position of the vehicle sensor 11 , and which has a length greater than the length of a standard vehicle and smaller than twice the length of the standard vehicle. For example, the predetermined service zone 17 has a length of about 4 m along the lane. For example, the position of the vehicle sensor 11 is rearward separate from the front edge of the predetermined service zone 17 by an interval of about 1 m. The predetermined service zone 17 is surrounded by a zone 18 forming a pseudo service zone. Within the pseudo service zone 18 , the intensity of a downward radio signal is equal to or greater than a certain level, for example, −70 dBm at which radio communication with an ETC vehicle may be established. The antenna 13 is designed to feature a predetermined directivity which causes the pseudo service zone 18 to be relatively narrow. For example, on the surface of the lane, the pseudo service zone 18 extends from a place following the rear edge of the predetermined service zone 17 by an interval of about 1.5 m to a place preceding the front edge of the predetermined service zone 17 by an interval of about 1 m. Preferably, the whole service zone equal to the combination of the predetermined service zone 17 and the pseudo service zone 18 has a length along the lane which is greater than the length of a standard vehicle and smaller than twice the length of the standard vehicle. For example, the length of the whole service zone is equal to about 6.5 m. As shown in FIG. 8 , the antenna 13 includes an insulating base board (an insulating substrate) 51 , patch antenna elements 52 , and feeder lines 53 . The patch antenna elements 52 are formed on the insulating base board 51 . The patch antenna elements 52 are arranged in a suitable array, for example, a two-dimensional matrix array. Each of the patch antenna elements 52 has a rectangular electrically-conductive plate. The feeder lines 53 are formed on the insulating base board 51 . The feeder lines 53 are connected to the patch antenna elements 52 , respectively. Radio power can be fed from the radio transceiver 13 A (see FIG. 7 ) to the patch antenna elements 52 via the feeder lines 53 . The number of the patch antenna elements 52 and the array of the patch antenna elements 52 are designed to provide the previously-mentioned predetermined directivity. The control program for the computer 12 A is designed to continuously activate the radio transceiver 13 A. Accordingly, the radio transceiver 13 A continuously outputs a radio signal to the antenna 13 , and the antenna 13 continuously radiates the radio signal as a downward radio signal. In the case where an ETC vehicle comes in, the on-vehicle machine of the ETC vehicle receives the downward radio signal and transmits an upward radio signal in response to the received downward radio signal. The upward radio signal is a response to the downward radio signal. The upward radio signal contains ID (identification) information, departure-place information, and information of places through which the vehicle passed. The upward radio signal is received by the antenna 13 . The received radio signal is fed from the antenna 13 to the radio transceiver 13 A. The radio transceiver 13 A extracts the information from the received radio signal. The radio transceiver 13 A outputs the extracted information to the computer 12 A. In this case, the computer 12 A is notified that a response to the downward radio signal has come from an incoming vehicle. On the other hand, in the case where a non-ETC vehicle comes in, any upward radio signal is not received by the antenna 13 and hence the radio transceiver 13 A continues to inform the computer 12 A that any response to the downward radio signal does not come. FIG. 9 shows a segment of the control program for the computer 12 A which is iterated, and which is executed for every incoming vehicle. As shown in FIG. 9 , a first step S 1 of the program segment decides whether or not a response to the downward radio signal is received by referring to the information given by the radio transceiver 13 A. When a response to the downward radio signal is received, the computer 12 A judges that there is an ETC vehicle incoming. In this case, the program advances from the step S 1 to a step S 2 . When a response to the downward radio signal is not received, the program advances from the step S 1 to a step S 3 . The step S 2 implements an accounting process related to the incoming ETC vehicle. A step S 4 following the step S 2 decides whether or not the incoming ETC vehicle reaches the lane position of the vehicle sensor 11 by referring to the output signal therefrom. When the incoming ETC vehicle reaches the lane position of the vehicle sensor 11 , the program exists from the step S 4 and then the current execution cycle of the program segment ends. The step S 3 decides whether or not an incoming vehicle reaches the lane position of the vehicle sensor 11 by referring to the output signal therefrom. When an incoming vehicle reaches the lane position of the vehicle sensor 11 , the computer 12 A judges that there is a non-ETC vehicle incoming. In this case, the program advances from the step S 3 to a step S 5 . When any incoming vehicle does not reach the lane position of the vehicle sensor 11 , the program returns from the step S 3 to the step S 1 . The step S 5 controls the guiding apparatus 19 to guide the incoming non-ETC vehicle to a tollbooth and to instruct the incoming non-ETC vehicle to pause at the tollbooth for manually paying toll. After the step S 5 , the current execution cycle of the program segment ends. As previously mentioned, the downward radio signal is continuously radiated from the antenna 13 . When a response to the downward radio signal is received, the computer 12 A judges that there is an ETC vehicle incoming. In the case where an incoming vehicle is detected by the vehicle sensor 11 while any response to the downward radio signal is not received, the computer 12 A judges that there is a non-ETC vehicle incoming. Since only one standard vehicle can be contained in the whole radio-communication service zone (the predetermined service zone 17 plus the pseudo service zone 18 ), an incoming non-ETC vehicle can be correctly detected even when the incoming non-ETC vehicle is immediately followed by an ETC vehicle. The ETC-system tollgate in FIGS. 5 and 6 has only one vehicle sensor 11 . Therefore, the ETC-system tollgate is relatively inexpensive. The antenna 13 may be replaced by another directional antenna. The vehicle sensor 11 may be of a type different from the optical type.
An ETC (electronic toll collection) system includes an antenna having a predetermined directivity for providing a limited radio-communication service zone. A vehicle sensor operates for detecting a vehicle which reaches a predetermined position in the limited radio-communication service zone. A radio signal is transmitted via the antenna. A decision is made as to whether or not a radio response to the radio signal is received via the antenna. In cases where a radio response to the radio signal is received, it is judged that there is an ETC vehicle incoming. In cases where the vehicle sensor detects a vehicle while a radio response to the radio signal is not received, it is judged that there is a non-ETC vehicle incoming.
6
BACKGROUND OF THE INVENTION The present invention relates generally to hermetic compressors of the type commonly installed in appliances, such as refrigerators, freezers, air conditioners, dehumidifiers, etc. More particularly, the invention pertains to a mounting apparatus for mounting such a compressor in an upright manner to a horizontal support surface associated with an appliance frame, enclosure, or cabinet. In a hermetic compressor of the type to which the present invention pertains, a motor compressor unit is operably disposed within a hermetically sealed outer housing. A hermetic electrical terminal and refrigeration fluid conduits extend through the sidewall of the housing and provide external access to the motor compressor unit contained therein. Accordingly, the hermetic compressor is easily incorporated into an appliance by simply mounting the compressor to the appliance cabinet and making the necessary electrical and refrigeration fluid connections. Because it is well known that hermetic compressors generate undesired noise and vibration, it is desired to mount the compressor to the appliance cabinet in such a manner as to suppress the noise and vibration and to absorb shock. Several methods are known for mounting a hermetic compressor in an appliance cabinet and, more specifically, for mounting the compressor to a horizontal support surface in an upright position. For example, it is known to weld a base plate to the bottom of the compressor housing, wherein the base plate is provided with a plurality of holes into which grommets are forcibly fit. Each grommet includes an aperture which houses a sleeve through which a nut and bolt assembly is received to secure the compressor and plate to the appliance. Similarly, it is known to weld a plurality of supporting legs to the compressor housing, which are then placed upon posts with resilient means interposed between the legs and the horizontal support surface. Each of the aforementioned prior art mounting methods requires that mounting apparatus be welded onto the compressor housing. The required mounting hardware and welding operation not only increases manufacturing cost of the compressor, but also subjects the housing to extreme heat which may result in undesired deformation of the housing. Also, the provision of a mounting plate and legs projecting from the housing could make assembly and shipping of the compressor more difficult. In other prior art mounting methods, the bottom of the compressor rests on resilient means interposed between the bottom of the compressor and the supporting base. For example, resilient grommets may be adhesively bonded within indentations on the bottom of a compressor housing, wherein the grommets are then mounted onto projections on the mounting base. In another mounting system of this type, the compressor rests upon a resilient member comprising a plurality of hollow spring cylinders engaging locations on the bottom of the compressor housing. In this latter mounting system, the compressor must be supported at its top end to insure vertical stability. This typically requires that a mounting stud be welded to the compressor housing and that additional support structure be provided, thereby adding to the cost and complexity of the mounting system. While various and several methods of mounting a compressor to an appliance cabinet or the like are known, it is desired to provide an improved mounting system, wherein both vibration imparted to the supporting base and noise radiating from the compressor housing are minimized. The problem of noise radiating from the compressor housing is particularly pronounced in the case of a compressor housing wherein an end plate of the compressor mechanism within the housing forms one end of the compressor housing. In such an arrangement, particularly where the end plate is adjacent the cylinder block of a rotary vane compressor mechanism, noises tend to radiate from the end plate. Accordingly, it is desired to provide an improved mounting apparatus for mounting a hermetic compressor to a horizontal support surface in an upright position, wherein additional mounting hardware on the compressor housing is not required and vibration and noise radiating from the compressor housing is suppressed. SUMMARY OF THE INVENTION The present invention provides a mounting apparatus for mounting a hermetic compressor to a horizontal support surface in an upright position, wherein a resilient member engages the bottom end of the compressor outer housing so as to substantially cover the housing bottom end, thereby isolating compressor vibration and suppressing noise radiating from the bottom end of the housing. In general, the invention provides a resilient cup-shaped body member having a bottom surface attachable to a horizontal support surface and a top surface including a receptacle to receive the bottom end of the compressor housing. The receptacle includes an opening on the top surface and a downwardly extending sidewall. When the compressor is received into the receptacle, the sidewall frictionally engages the compressor housing to ensure vertical stability. In one aspect of the invention, the receptacle includes a bottom wall, which is spaced from the bottom of the compressor housing when the compressor is received in the receptacle, whereby the compressor housing and receptacle define a substantially enclosed chamber for suppressing noise radiating from the bottom of the housing. More specifically, the invention provides, in one form thereof, a resilient cup-shaped body member including a generally cylindrical wall portion having a diameter less than the diameter of the generally cylindrical sidewall of the compressor housing. Accordingly, when the bottom end of the compressor housing is force-fittedly introduced into the body member, the sidewall is resiliently biased against the compressor housing to retain the bottom end of the compressor within the body member. In one aspect of the invention according to this form thereof, the bottom end of the compressor housing includes a radially extending flange portion, which causes a circumjacent portion of the sidewall to be stretched radially outwardly so as to envelope the flange portion, thereby restricting vertical movement of the compressor. In accordance with this aspect of the invention, the location of engagement of the flange portion with the sidewall is spaced from the intersection between the sidewall and a bottom wall of the cup-shaped body member. An advantage of the mounting boot of the present invention is that a compressor may be mounted to a support base without the need for hardware welded to the outside of the compressor housing. Another advantage of the mounting boot of the present invention is that sound radiating from the bottom of the compressor housing is suppressed. A further advantage of the mounting boot of the present invention is that suppression of vibration and sound from a compressor mounted within an appliance cabinet is simply and economically achieved. Another advantage of the mounting boot of the present invention is that the particular frictional engagement of the boot with the compressor housing is maintained despite vibratory and shock forces that might otherwise cause disengagement. A still further advantage of the mounting boot of the present invention, in one form thereof, is that mounting of a compressor to a support base is accomplished with a single part, i.e., a resilient body member, thereby simplifying installation. Another advantage of the mounting boot of the present invention, in one form thereof, is the versatility in mounting the boot to any horizontal support base, due to the provision of integrally formed, radially extending mounting feet. Yet another advantage of the mounting boot of the present invention is that refrigeration fluid conduits present on the mounting end of the compressor housing may be accommodated by the provision of passages formed in the mounting boot. The invention, in one form thereof, provides a vertically upright hermetic compressor for mounting to a horizontal support surface. The compressor includes a housing having a motor compressor unit operably disposed therein. A mounting apparatus is removably attached to the bottom end of the housing, whereby the compressor may be mounted to the horizontal support surface. The mounting apparatus comprises a resilient body member engaged with the housing to substantially cover the housing bottom end. The invention further provides, in one form thereof, a mounting apparatus for mounting a hermetic compressor to a horizontal support surface in a vertically upright manner. The mounting apparatus comprises a resilient body member including a bottom surface and a top surface. The bottom surface is attachable to the horizontal support surface, while the top surface includes a receptacle for receiving a bottom portion of the compressor. The receptacle comprises an opening on the body member top surface, and a sidewall adapted to frictionally engage the compressor. The invention still further provides, in one form thereof, a vertically upright hermetic compressor for mounting to a horizontal support surface. The compressor comprises an outer housing having operably disposed therein a motor compressor unit. The housing includes a top end, a generally cylindrical central portion, and a bottom end. The housing also includes a radially outwardly extending flange portion adjacent the bottom end. In one aspect of the invention, the housing bottom end comprises a plate member constituting a part of the motor compressor unit. The compressor also includes a cup-shaped body member, attachable to the horizontal support surface, for mounting the compressor to the horizontal support surface in a vertically upright manner. The body member includes a resilient upwardly extending wall portion having a generally cylindrical inner wall with which the flange portion operably engages. The inner wall has a diameter less than the diameter of the flange portion, whereby the wall portion is resiliently biased against the flange portion. In another aspect of the present invention according to this form, the body member includes a bottom wall generally intersecting at its perimeter with the cylindrical inner wall of the wall portion. In such an arrangement, a spacer is provided for spacing the location of engagement of the compressor with the inner wall from the intersection between the bottom wall and the inner wall when the compressor is operably mounted within the mounting apparatus. Alternatively, the body member may include a bottom wall having a peripheral planar portion against which the compressor bottom end abuts. In this arrangement, the planar portion has an annular channel formed therein adjacent the wall portion to axially extend the cylindrical inner wall below the planar portion. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side sectional view of a hermetic compressor and mounting boot assembly in accordance with the present invention; FIG. 2 is a bottom view of the hermetic compressor and mounting boot assembly of FIG. 1, particularly showing the suction inlet tube of the compressor; FIG. 3 is a top view of the mounting boot of FIG. 1; and FIG. 4 is a sectional view of the mounting boot of FIG. 1, taken along the line 4--4 in FIG. 3 and viewed in the direction of the arrows. DESCRIPTION OF THE PREFERRED EMBODIMENT In an exemplary embodiment of the invention as shown in the drawings, and in particular by referring to FIG. 1, a vertical axis hermetic compressor 10 is shown having a housing generally designated at 12. Housing 12 comprises a top portion 14, a generally cylindrical central portion 16, and a bottom end plate 18. The three housing portions are hermetically secured together as by welding or brazing. Disposed within housing 12 is a motor compressor unit comprising an electric motor generally designated at 20 and a rotary vane compressor mechanism generally designated at 22. Motor 20 comprises a stator 24 having windings 26, and a rotor 28. Stator 24 is secured to housing 12 by an interference fit, such as by shrink fitting. Rotor 28 has a central aperture 30 provided therein into which is secured a rotatable crankshaft 32, such as by an interference fit. Crankshaft 32 includes an eccentric portion 33 drivingly connected to compressor mechanism 22, which compresses refrigerant for discharge into the interior of housing 12. A refrigerant discharge tube 34 is sealingly connected to top portion 14 of the housing as by soldering. Likewise, a hermetic electric terminal 36 is also secured to top portion 14, wherein a connector 38 connects to terminal 36 on the interior of housing 12 to supply electric power to motor 20. As previously described, compressor mechanism 22 of the illustrated embodiment is a rotary vane compressor mechanism substantially the same as that shown and described in U.S. Pat. No. 4,730,994, issued to Maertens and assigned to the same assignee as the present invention, the disclosure of which is hereby incorporated herein by reference. A brief description of compressor mechanism 22 is provided herein to aid in the understanding of the present invention. Accordingly, compressor mechanism 22 includes a main bearing 40 in which crankshaft 32 is rotatably journalled, end plate 18, and a compressor cylinder block 42 disposed intermediate main bearing 40 and end plate 18. As illustrated in FIG. 1, end plate 18 is secured to main bearing 40 by means of a plurality of bolts 44. Cylinder block 42 defines an axial bore 46 which, together with main bearing 40 and end plate 18, defines a compression chamber 48. A roller 50 surrounds crankshaft eccentric 33 in compression chamber 48, and cooperates with a sliding vane 52 in a conventional manner for compressing a refrigerant fluid in compression chamber 48. Furthermore, a vane spring 54 provides a bias force to the back of the sliding vane 52. Compressor mechanism 22 also includes a lubrication system, more fully described in U.S. Pat. No. 4,730,994, including helical passageways 56 formed in crankshaft 32, axial passage 58 formed in cylinder block 42, and radial passage 60 formed in end plate 18. In operation of compressor 10, gas refrigerant enters compressor mechanism 22 through a suction inlet tube 62 mounted to a suction aperture 64 provided in end plate 18, as shown in FIG. 2. Gas refrigerant flowing into aperture 64 enters compression chamber 48 and is compressed by operation of roller 50 and sliding vane 52 as crankshaft 32 is rotatingly driven by rotor 28 of motor 20. Thereafter, the compressed refrigerant is discharged through a discharge valve (not shown) into the interior of housing 12 through a discharge muffler 66, and then through discharge tube 34 to the condenser of a refrigeration circuit as known in the art. End plate 18, as previously described, constitutes a part of compressor mechanism 22, while at the same time serves as the bottom end of housing 12. More specifically, end plate 18 is a circular-shaped plate member having a top surface 68 and a bottom surface 70. At the periphery of end plate 18, an annular groove 72 is formed in top surface 68, into which central portion 16 is received and secured to end plate 18 by means of weldment 74. As illustrated in FIG. 1, end plate 18 includes a flange portion 76 having greater diameter than central portion 16 and, hence, extending radially outwardly therefrom. Flange portion 76 includes a radially outwardly facing surface 78. FIG. 1 also illustrates that end plate bottom surface 70 generally comprises a radially outermost annular support surface 80, a radially innermost circular area 82, and a radially intermediate annular recess 84, wherein surface 80 is located in a plane axially between planar area 82 and the planar bottom of recess 84. In accordance with the principles of the present invention, a resilient, cup-shaped mounting boot 86 is removably attached to the bottom end of compressor 10 so as to mount compressor 10 in an upright position on a horizontal support surface (not shown). In accordance with a preferred embodiment, mounting boot 86 is a unitary body member, molded from Santoprene thermoplastic rubber material available from Monsanto Corporation of St. Louis, Mo. However, it will be appreciated that other suitable resilient rubber-like materials may be used. FIGS. 1 and 2 illustrate mounting boot 86 operably engaged with compressor 10, while FIGS. 3 and 4 illustrate specific structural features of mounting boot 86 more fully described hereinafter. Referring now to FIGS. 2-4, mounting boot 86 comprises a cup-shaped body member including a top surface 88 and a substantially horizontal bottom surface 90. Top surface 88 includes an opening 92, an upwardly extending wall portion 94 having an inwardly facing sidewall 96, and a bottom wall 98, which together define a receptacle 100 into which the bottom end of compressor 10 is received through opening 92. Sidewall 96 extends downwardly so as to generally intersect with bottom wall 98 at a perimeter 102 thereof. Bottom wall 98 includes a central recess 104, an annular platform 106 circumjacent recess 104, and an annular channel 108 circumjacent platform 106. As illustrated, recess 104 and channel 108 represent areas of bottom wall 98 having a reduced axial thickness. An annular bevelled shoulder 110 is provided on the outside of wall portion 94 adjacent top surface 88. In accordance with one embodiment of the present invention, mounting boot 86 has integrally formed therewith a plurality of radially extending foot portions 112 for mounting the boot to a horizontal support surface within an appliance frame, enclosure, or cabinet. Each foot portion 112 includes an aperture 114 extending axially therethrough, which may house a sleeve through which a nut and bolt assembly is received to secure mounting boot 86 to the support surface. Each foot portion 112 also includes a spacer portion 116, whereby spacer portions 116 contact with the horizontal support surface while maintaining bottom surface 90 spaced therefrom. Alternatively, mounting boot 86 may be attached to a horizontal support surface without foot portions 112. For example, bottom surface 90 could directly contact the support surface and the attached thereto with an adhesive or the like. Referring to FIGS. 2 and 3, suction inlet tube 62 extends from bottom surface 70 of compressor 10, and passes through a passage 118 formed in bottom wall 98 of boot 86. More specifically, passage 118 extends radially outwardly to an opening 120 on the outer periphery of boot 86, whereby suction inlet tube extends axially downwardly from bottom surface 70, makes a right-angled turn, and extends radially outwardly from the mounting boot, as shown in FIG. 2. Referring once again to FIG. 1, the engagement of mounting boot 86 with compressor housing 12, in accordance with a preferred embodiment of the invention, will now be more fully described. Generally, the compressor housing is frictionally engaged by the mounting boot, whereby the bottom end of the compressor housing is substantially covered by the mounting boot and the compressor is prevented from moving vertically out of its mounted position without the requirement of additional mounting hardware. More specifically, outwardly facing surface 78 of flange portion 76 engages sidewall 96 of boot 86. The outside diameter of flange 76 is slightly larger than the inside diameter of sidewall 96, whereby the sidewall is resiliently biased against the flange portion when the compressor is operably mounted. For example, in one embodiment of the invention, the outside diameter of flange 76 is approximately 4.905 inches, while the inside diameter of sidewall 96 is approximately 4.830 inches. As illustrated in FIG. 4, cylindrical wall portion 94 is substantially vertical in the absence of compressor 10 being engaged with boot 86. However, as illustrated in FIG. 1, when the bottom end of compressor 10 is inserted into receptacle 100, the aforementioned difference in diameters causes a bowing out of wall 94 centered at a point of contact 122 of flange 76 with wall 94, whereat radially outward force is exerted on sidewall 96. More specifically, an uppermost portion 124 of wall 94 tends to curl radially inwardly over the point of contact 122 or, in other words, the sidewall is stretched radially outwardly so as to envelope the flange portion. This bowing or enveloping action restrains the compressor against vertical movement caused by vibratory and/or shock forces. Another important aspect of the present invention is that the location of engagement of flange 76 with wall 94, i.e., point of contact 122, is spaced from the intersection between sidewall 96 and bottom wall 98 at perimeter 102. If the point of contact 122 were permitted to approach the intersection between the bottom and side walls, wall 96 would no longer be able to envelope the flange portion just below the point of contact. Accordingly, the radially outward force on wall 96 would become leveraged so as to cause bottom wall 98 to bow upwardly at the center thereof, and wall 94 to open in conical fashion, thereby reducing the restraint of the compressor in the vertical direction. To insure that point of contact 122 remains axially spaced from the point of intersection at perimeter 102, annular channel 102 and platform 106 cooperate so that annular support surface 80 abuts against platform 106, whereby annular channel 108 effectively permits sidewall 96 to extend below the planar top surface of platform 106, as illustrated in FIG. 1. Accordingly, when compressor 10 is inserted into receptacle 100 so that support surface 80 abuts the top surface of platform 106, flange 76 exerts a radially outward force on wall 94 at a point of contact 122 spaced from the intersection between the side and bottom walls of boot 86 at perimeter 102. This spacing permits wall 96 to surround or envelope flange 76 for vertical stability of compressor 10. Finally, the previously described abutment of annular support surface 80 with the top surface of annular platform 106 is designed such that bottom surface 70 remains spaced from bottom wall 98, particularly central recess 104, whereby a substantially enclosed chamber 126 is defined to suppress noise radiated from end plate 18 during compressor operation. Where end plate 18 constitutes a component of a rotary vane compressor mechanism which helps define the compression chamber, the noise radiated from end plate 18 can be especially pronounced. Accordingly, in the preferred embodiment of the present invention described herein, the provision of chamber 126 for suppression of noise radiated from the bottom end of the compressor housing is particularly advantageous. It will be appreciated that the foregoing is presented by way of illustration only, and not by way of any limitation, and that various alternatives and modification may be made to the illustrated embodiment without departing from the spirit and scope of the invention.
A mounting boot for mounting a vertical hermetic compressor to a horizontal base, includes a resilient cup-shaped member to receive the bottom end of the compressor housing. A cylindrical inner wall surface of the cup-shaped member frictionally engages the sidewall of the compressor. The bottom end of the compressor housing comprises a plate member having a radially extending flange portion resiliently enveloped by the inner wall surface of the cup-shaped member. The bottom end of the compressor housing is spaced from the bottom wall of the mounting boot, thereby defining an enclosed muffling chamber to suppress noises radiated from the compressor bottom end. The mounting boot is formed with radially extending mounting feet, and passages through which compressor inlet and outlet tubes may extend.
8
FIELD OF THE INVENTION [0001] The present invention generally relates to security devices, and specifically to lockable devices of the type comprising a lock-body arrestable against a dedicated slot formed in a side-wall of the protected object, such as a portable computer, and a cable connected at one end to the lock-body whereas the other end is adapted to be tied to an immovable object such as a table leg. BACKGROUND OF THE INVENTION [0002] Locks of the type above referred to are widely used. The most popular models are known in commerce as “KENSINGTON” locks (see for example U.S. Pat. Nos. 7,100,403, 7,111,479, and many others). [0003] Rapid advances in technology continuously contribute to development of smaller computers, including smaller portable computers such as laptops and notebooks. As external dimensions are reduced in the portable computers, so is generally an area of a side-wall of the computer in which is formed the dedicated slot adapted to accommodate the lock-body. In some cases, the area is reduced to such an extent that the dedicated slot cannot be formed in the side-wall. Such is the case, for example, with the Apple MacBook Air portable computer. Consequently, the locking technique of the type above referred to is not pacticable. Computers of this type shall be herein referred to as “Flat Computers”. [0004] It is therefore the prime object of the invention to offer a solution to this problem. [0005] It is a further object of the invention to provide a novel locking arrangement that will eliminate the need for a dedicated slot to be formed on a side wall of the protected object. SUMMARY OF THE INVENTION [0006] According to one aspect of the invention there is provided a method of arresting a portable object having a housing with an underside housing cover by a cable adapted to be tied to an immovable object. The cable is provided with a key-operated locking device comprising a tip insertible into a dedicated slot associated with the portable object and turned by the key by an angle less than 180° thereby preventing the withdrawal of the tip from the dedicated slot. The method comprises the steps of providing an auxiliary base-plates formed with at-least one dependent wall portion comprising said dedicated slot; attaching the auxiliary base-plate to the underside housing cover of the portable object; and arresting the auxiliary base-plate to an immovable object by said locking device. [0007] According to another aspect of the invention, the auxiliary base-plate is configured to fit against the underside housing cover and comprising at-least one dependent wall portion formed with said dedicated slot, and means for securing the base-plate to the underside housing cover. BRIEF DESCRIPTION OF THE DRAWINGS [0008] These and additional constructional features and advantages of the invention will become more clearly understood in the light of the following description of several preferred embodiments thereof given by way of example only, with reference to the attached drawings, wherein— [0009] FIG. 1 is a schematic front-side view of a typical flat computer housing; [0010] FIG. 2 is a cross-sectional view II-II of the computer housing of FIG. 1 ; [0011] FIG. 3 is a schematic first side view of an auxiliary base-plate designed according to the principles of the present invention; [0012] FIG. 4 is a schematic second side view of the base-plate of FIG. 3 ; [0013] FIG. 5 is a schematic side view of the base-plate opposite to that of FIG. 4 ; [0014] FIG. 6 is a schematic top view of the base-plate of FIG. 3 ; [0015] FIG. 7 is a schematic sectional view taken along line VII-VII of FIG. 6 including a cross-sectional view of a first lock-body, according to a first preferred embodiment of the present invention; [0016] FIG. 8 illustrates a position prior to mounting the first lock-body to the base-plate; [0017] FIG. 9 shows a different view of FIG. 8 ; [0018] FIG. 10 illustrates the locking position of the first lock-body in the base-plate; [0019] FIG. 11 is a schematic sectional view taken along line XI-XI of FIG. 6 including a cross-sectional view of a second lock-body, according to another embodiment of the present invention; [0020] FIG. 12 illustrates a position prior to mounting the second lock-body to the base-plate; [0021] FIG. 13 shows the second lock-body mounted on the base-plate prior to locking; and [0022] FIG. 14 illustrates the locking position of the second lock-body to the base-plate. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [0023] In FIGS. 1 and 2 , a portable object which may be, for example, a flat computer housing generally designated 10 , is shown in a front view and a cross-sectional view II-II, respectively. Cross-sectional view II-II cuts through three screw holes 12 positioned on an underside housing cover 13 of flat computer 10 , in each screw hole inserted a screw 11 . On an opposing side of underside housing cover 13 are additional three screw holes 12 and inserted screws 11 . Screws 11 may be used soley to secure underside housing cover 13 of computer 10 , and/or to secure parts and components (not shown) inside the computer. Optionally, screw holes 12 and screws 11 may be used to attach an object or a device to underside 13 . Optionally, the quantity and/or location of screws holes 12 and screws 11 on underside 13 may differ from one model of flat computer to another. [0024] In FIGS. 3 , 4 , 5 and 6 , an auxiliary base-plate 20 for securing computer 10 to an immovable object (not shown) is shown in a front view, left side view, right side view, and top view, respectively. Base-plate 20 is configured in various respect to fit the underside housing cover 13 . Hence, it may include a plurality of utility openings adapted to allow access to compartments, openings, and connectors of computer 10 ; it may include ventilation openings 32 which may align with ventilation openings in computer 10 ; it may include a port connector opening 29 A through which devices and accessories may be connected to computer 10 ; Additionally or alternatively, it may include a power connector opening 29 B through which a power cord may be inserted and connected to computer 10 ; it may further comprise recesses such as, for example recess 24 , for facilitating user access while opening the computer; and it may include one or more holes 27 through which screws may be inserted for attaching the auxiliary base-plate 20 to underside 13 of computer 10 . [0025] Attachment of the base-plate 20 to underside housing cover 13 is typically done by first placing the flat computer 10 in right-side-down position (underside 13 is facing upwards) which allows for removing screws 11 from screw holes 12 . Following removal of screws 11 , base-plate 20 is onto underside 13 such that the one or more holes 27 thereof are aligned with screw holes 12 on the underside housing cover 13 . Additionally, utility openings such as, for example port connector opening 29 A, power connector opening 29 B, and ventilation openings 32 , are properly positioned relative to underside 13 . Once aligned, replacement (longer), screws 11 ′ are inserted through holes 27 into screw holes 12 , and tightened. Following attachment of base-plate 20 to underside 13 , computer 10 , together with the attached plate, may be placed in a right-is side up position (underside 13 is facing downwards) and set to rest on a flat surface on supports 23 included in the base-plate. [0026] Base-plate 20 further comprises a first dedicated slot 22 A which may be formed in a dependent wall 22 C of a first lock chamber 22 . First lock chamber 22 , which may be integrally formed as a part of auxiliary base-plate 20 , comprises a housing with an internal cavity (designated 22 B in FIG. 7 ) to allow for a lock tip (designated 43 in FIG. 7 below) to be inserted through first dedicated slot 22 A in a locking operation. Optionally, first lock chamber 22 may be separately attached to plate 20 by fastening means such as, for example, a screw, a bolt, or the like. First dedicated slot 22 A, which may be triangular as shown, may optionally have other shapes compatible with the shape of the lock tip (see below). [0027] As shown in FIGS. 7 and 8 , first dedicated slot 22 A is adapted to become selectively locked against, and unlocked from, a first lock-body 40 . First lock-body 40 comprises a housing 44 , for example a cylindrical housing, accommodating a locking mechanism which may be of the push-button type, operable by key 41 . Affixed to housing 44 is one end of a security cable 46 , for example a metal cable, including a looped end 46 A by which the cable may be tied around a fixed object such as a table leg 45 . [0028] As shown in greater detail in FIGS. 9 and 10 , locking of first lock-body 40 to depended wall 22 C of first lock chamber 22 , and thereby to the back-plate 20 , is achieved by inserting a pair of triangular overlapping lock tips 42 and 43 that fit respectively into and through first dedicated slot 22 A. The tip 42 is fixed to lock body 44 . A mechanism in housing 44 , operated by key 41 , is adapted to rotate tip 43 in either direction, for example by 60°, to complete the locking operation as shown in FIG. 10 . [0029] Auxiliary lock-plate 20 may additionally comprise, say, for extra safety, a second dedicated slot 21 A which may be formed in a dependent wall 21 C of a second lock chamber 21 . Second lock chamber 21 , which may be integrally formed as a part of the plate, comprises a housing with an internal cavity (designated 21 B in FIG. 11 ) to allow for a lock tip 52 to be inserted through second dedicated slot 21 A in a locking operation. Optionally, second lock chamber 21 may be separately attached to lock-plate 20 by fastening means such as, for example, a screw, a bolt, or the like. Second dedicated slot 21 A, which may be of an oblong rectangular shape as shown, may optionally have other shapes compatible with the shape of the lock tip. [0030] As shown in FIGS. 11 and 12 , second dedicated slot 21 A is adapted to become selectively locked against, and unlocked from, a second lock-body 50 . Second lock-body 50 comprises a housing 54 , for example a cylindrical housing, accommodating a locking mechanism which may be of the push-button type, operable by a key 51 . Affixed to housing 54 is one end of a security cable 56 , for example a metal cable, including a looped end 56 A by which it can be tied around table leg 45 . [0031] As shown in greater detail in FIGS. 13 and 14 , locking of second lock-body 50 to dependent wall 21 C of second lock chamber 21 , and thereby to back-plate 20 , is achieved by inserting a lock tip 52 that fits into and through second dedicated slot 21 A. A mechanism in housing 54 , operated by key 51 , is adapted to rotate tip 52 in either direction, for example by 90°, to complete the locking operation as shown in FIG. 14 . [0032] Those skilled in the art to which this invention pertains will readily appreciate that numerous changes, variations and modifications can effectuated without departing from the scope of the invention as defined in and by the appendent claims.
For use in arresting a portable object such as flat laptop computers ( 10 ) having a housing with an underside housing cover ( 13 ) by a cable ( 46 ) adapted to be tied to an immovable object ( 45 ), the cable being provided with a key-operated locking device ( 44 ) comprising a tip ( 43 ) insertable into a dedicated slot ( 22 A) associated with the portable object and turned by the key ( 41 ) by an angle less than 180 thereby preventing the withdrawal of the tip from the dedicated slot, an auxiliary base-plate ( 20 ) configured to fit against the underside housing cover ( 13 ) and comprising at-least one dependent wall portion ( 22 C) formed with the dedicated slot ( 22 A), and means ( 11 ′) for securing the base-plate to the underside housing cover.
4
FIELD OF THE INVENTION This invention relates generally to communications systems and, in particular such communications in a wireless local area network (LAN). Specifically, the invention is directed to assignment of network resources in communication systems using shared multiple access communication media, such as, for instance, frequency hopping patterns, in a multicell radio LAN based on slow frequency hopping spread spectrum signaling. BACKGROUND OF THE INVENTION In a wireless LAN network various configuration parameters or network resources have to be maintained and distributed as base stations and remote stations enter or leave the network. A typical wireless LAN topology is divided into cells. Associated with each cell is a base station connected to a backbone network which acts as an access point and relay for remote stations. To become part of the network, remote stations have to register with one of the base stations. All communications between the remote station and other entities are subsequently handled by the base station with which the remote station has registered. For instance a multicell radio LAN installation based on slow frequency hopping spread spectrum signaling may consist of a set of base stations with overlapping coverage areas. In a frequency hopping (FH) system, the carrier frequency of the transmitter changes at intervals of time, remaining constant between those instants. The period of constant frequency is called a hop and messages may be exchanged during these hops. Efficient methods for controlling and minimizing radio interference between overlapping cells are essential to the reliability and performance of such radio LAN installations. The transmission and reception of messages in a cell of a multicell network of the type that employs identical communication frequencies in different cells, requires control of interference between users. This interference may occur from several sources including transmission from remote stations that lie in overlapping areas between adjacent cells and transmissions from base stations if these overlapping cell areas contain one or more remote users. Assigning different frequency hopping sequences or patterns to base stations with overlapping coverage areas allows control and limit interferences. The following U.S. Patents and European Patent applications teach various aspects of mobile communications using wireless transmission media. U.S. Pat. No. 5,239,673 teaches a scheduling method for efficient frequency reuse in a multi-cell wireless network served by a wired local area network. One method of the invention circulates a high priority token among a plurality of header stations connected to the wired network. Reception of the token causes the receiving header station to perform wireless communications. when finished, the header station forwards the token to another header station. The following two U.S. Patents show communication systems having overlapping coverage areas: U.S. Pat. No. 4,597,105, Jun. 24, 1986, entitled "Data Communications System having Overlapping Receiver coverage Zones" to Freeburg and U.S. Pat. No. 4,881,271 issued Nov. 14, 1989, entitled "Portable Wireless Communication Systems" to Yamauchi et al. provide for a hand-off of a subscriber station from one base station to another by the base station continually monitoring the signal strength of the subscriber station. The following U.S. Patents teach various aspects of wireless communication networks. In U.S. Pat. No. 4,792,942, issued Dec. 20, 1988 entitled "Wireless Local Area Network for Use in Neighborhoods" S. Mayo describes a local area network that includes transceiver stations serially coupled in a loop. In U.S. Pat. No. 4,730,310 issued Mar. 8, 1988 entitled "Terrestrial Communications Systems" Acampora et al. describe a communications system that employs spot beams, TDMA and frequency reuse to provide communication between a base station and remote stations. In U.S. Pat. No. 4,639,914, issued Jan. 27, 1987 entitled "Wireless PBX/LAN System with Optimum Combining" Winters discloses a wireless LAN system that employs adaptive signal processing to dynamically reassign a user from one channel to another. In U.S. Pat. No. 4,926,495, issued May 15, 1990 entitled "Computer Aided Dispatch System" Comroe et al. disclose a computer aided dispatch system that includes a master file node and a plurality of user nodes. The master file node maintains a record for each subscriber and automatically transmits an updated record to each dispatcher attached to a subgroup in which the subscriber operates. In U.S. Pat. No. 4,456,793, issued Jun. 26, 1984 W. E. Baker et al. describe a cordless telephone system having infrared wireless links between handsets and transponders. The transponders are wired to subsystem controllers that are in turn wired to a system controller. The central controller polls the cordless stations every 100 milliseconds to detect cordless station locations and to identify "missing" cordless stations. In U.S. Pat. No. 4,807,222, issued Feb. 21, 1989 N. Amitay described a LAN in which users communicate with RF or IR signals with an assigned Regional Bus Interface Unit (RBIU). Protocols such as CSMA/CD and slotted ALOHA are employed in communicating with the RBIUs. In U.S. Pat. No. 4,402,090 issued Aug. 30, 1983, F. Gfeller et al. describe an infrared communication system that operates between a plurality of satellite stations and a plurality of terminal stations. A host computer communicates with the terminal stations via a cluster controller and the satellite stations, which may be ceiling mounted. Communication with the terminal stations is not interrupted even during movement of the terminal stations. In IBM Technical Disclosure Bulletin, vol. 24, No 8, page 4043, January 1982 F. Gfeller describes general control principles of an infrared wireless network incorporating multiple ceiling mounted transponders that couple a host/controller to multiple terminal stations. Access to the uplink channel is controlled by a Carrier Sense Multiple Access/Collision Detection (CSMA/CD) method. What is not taught in the prior art is a method for reusing frequency hopping patterns thus allowing operation of frequency hopping wireless LAN's with a number of base stations greater than the number of existing frequency hopping patterns. More generally such method applies to the allocation of other kinds of network resources, such as a limited pool of remote stations addresses. In addition the method of the invention applies as well to wireless systems using different signalling techniques such as for instance direct sequence spread system radio frequency signalling or infrared and more generally to any communication system using a multiple access shared communication medium. SUMMARY OF THE INVENTION The invention as defined is to provide a method for reusing a limited number of network resources in a communication system using a multiple access shared communication medium such as a wireless radio frequency (RF) or infrared (IR) communication network coupled to a local area network connected to a plurality of base stations. Each base station has a geographic area, defined as a cell, within which remote stations are within reception range. Remote stations select one base station as home base station. Home base stations are capable of performing bidirectional communication with one or more remote stations under control of a controller connected to said local area network, the method of the invention comprises the steps of: (a) requesting by a given base station assignment by said controller of one of said network resources; and (b) selecting and assigning by said controller one of said network resources; This method allows selecting and assigning one of the network resources already assigned to one or more other base stations. Selection is based on the computation by the controller of a distance index between the given base station and the other base stations. The resource assigned to the given base station is the one already assigned to one of the other base stations with the highest distance index to the given base station. In a wireless communication system using frequency hopping RF communication, this method is particularly suited to reuse frequency hopping patterns when the number of active base stations exceeds the number of available frequency hopping patterns. Assigning a frequency hopping pattern already in use by a base station with the highest distance index reduces the risk of interference between two base stations using the same frequency hopping pattern. Another aspect of the invention is to compute distance index based on data representative of base stations cells overlaps. Such cells overlap occurs at locations where a remote station is within RF or IR reception range of several active base stations. Cells overlaps information is used by the controller to reuse a network resource to assign it to a requesting base station. The method used to compute a distance index between the requesting base station and the other active base stations comprises the following steps: (a) setting the distance index of the other base stations to an initial maximum value; (b) setting the distance index to 1 for first level neighbor base stations, first level neighbors being defined as base stations whose cell overlaps with the requesting base station cell; and (c) starting with n=1, performing a number of iterations consisting in setting the distance index to n+1 for (n+1)-th level neighbor base stations, (n+1)-th level neighbors being defined as base stations whose cell overlaps with the cell of a n-th level neighbor base station. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a pictorial diagram showing an indoor radio digital communications system of the type in which the invention is implemented. FIG. 1A is a block diagram of the system shown in FIG. 1 illustrating the basic components of a remote station and a base station. FIG. 2 is a block diagram of the radio system used in the implementation of a preferred embodiment of the invention. FIG. 3 is a data framing diagram showing one medium access central protocol which may be implemented in a preferred embodiment of the invention. FIG. 3A is a data framing diagram showing a modification of the basic protocol illustrated in FIG. 3. FIG. 4 is a block diagram of a single cell wireless LAN system showing a possible option for wireless network controller and wireless control agent functions placement. FIG. 5 is a block diagram of a multiple cell wireless LAN system in which the wireless network controller and wireless control agents are located in different physical units. FIG. 6 is a flow chart providing an overview of frequency hopping patterns management in a multiple cell wireless LAN system. FIG. 7 is an illustration of a superframe structure used in a frequency hopping wireless LAN system. FIG. 8 is a set of radio frequency channels from which frequency hopping patterns can be selected. FIG. 9 shows the general structure of a frequency hopping pattern request packet. FIG. 10 is a flow chart of the process performed by the wireless network controller to assign a frequency hopping pattern to a base station. FIG. 11 shows the general structure of the response packet to a frequency hopping pattern request. FIG. 12 shows the contents and the structure of the wireless network control database used by the wireless network controller. FIG. 13 and 13A are flow diagrams of the process performed by the wireless network controller to reuse already assigned frequency hopping patterns. FIG. 14 and 14A are flow diagrams of the process performed by the wireless network controller to reuse already assigned base stations identifiers. DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings, and more particularly to FIG. 1, there is shown an indoor radio system allowing communication between a plurality of remote stations 10, 12, 14, and 16 and applications and data residing in a computing system. It is to be appreciated that other systems may be utilized in the practice of the invention. The computing system typically includes a Wireless Network Controller (WNC) 18, with attached monitor 20 and keyboard 22, of a local area network (LAN), generally indicated by reference numeral 24, having a plurality of attached workstations or personal computers (not shown for simplicity). Also attached to the LAN are one or more gateways 26 and 28 with which the remote stations 10, 12, 14, and 16 communicate. These gateways, referred to as base stations, are augmented according to the invention to provide certain radio system management functions which coordinate the remote stations' access to the common radio channel. Communications between remote stations is supported via relay through the base stations 26 and 28. As shown in more detail in FIG. 1A, a base station 26 or 28, which may be a conventional microcomputer, has a LAN adapter 30 inserted in a bus slot and connected to LAN cabling 32. The WNC 18, typically also a conventional microcomputer and including one or more direct access storage devices (DASDs) such as hard disks (not shown) , also has a LAN adapter 34 inserted in a bus slot and connected to LAN cabling 32. The LAN adapters 30 and 34 and the LAN cabling 32 together with LAN software constitute the LAN 24. The LAN 24 is of conventional design and does not form part of the invention. The base station 26 or 28 also has an RF transceiver adapter 36 implemented as a printed circuit card which is inserted in a bus slot of the base station. The transceiver adapter 36 includes a spread spectrum transceiver of conventional design. The transceiver adapter 36 has an antenna 38 by which a radio link 40 is established with one or more remote stations, 10, 12, 14, or 16. The remote station may itself be a hand held or lap top computer of conventional design and, like the base station, it is provided with an antenna 42 and a transceiver adapter 44, which may also be implemented as a printed circuit card which is inserted in a bus slot of the computer. The transceiver adapter 44, like transceiver adapter 36, includes a spread spectrum transceiver of similar design. The base station and the remote stations are further provided with software, generally indicated by reference numerals 46 and 48, respectively, which support their respective transceiver adapters. FIG. 2 shows the radio system common to both the remote stations and the base stations of FIG. 1. The radio system includes a transceiver adapter 44 connected to the computer 50 via the computer's bus interface 52. The transceiver section is itself divided into an RF transceiver 54, which may be a commercially available spread spectrum transceiver, and a dedicated microprocessor system 56 which controls the transceiver via an interface 58. The microprocessor system 56 further includes a system interface 60 which interfaces the transceiver section to the computer section 50. The microprocessor system includes a dedicated microprocessor 62 containing high-resolution time interval determination hardware or "timers" typical of real-time microprocessor systems. Microprocessor 62 is connected by a memory bus 64 to program storage 66 and data storage 68 as well as to interfaces 60 and 58 providing attachment to bus interface 52 and RF transceiver 54, respectively. Program storage 66 is typically read only memory (ROM) , while data storage 68 is static or dynamic random access memory (SRAM or DRAM). Packets received or to be sent are held in data storage 68 and communicated to or from the RF transceiver 54 via interface 58 under control of serial channels and a direct memory access (DMA) controller (not shown) which is part of the microprocessor 62. The function of these serial channels is to encapsulate data and control information in an HDLC (high-level data link control) packet structure and provide the packet in serial form to the RF transceiver 54. For more information on the HDLC packet structure, see for example, Mischa Schwartz, Telecommunication Networks: Protocols, Modeling and Analysis, Addison-Wesley (1988). When a packet is received through the RF transceiver 54, the serial channels check the packet destination address, check for errors, and deserialize the packet to data storage 68. The serial channels must have the capability to recognize a specific adaptor address as well as a broadcast address. Specific microprocessors with appropriate serial channel and timer facilities include the Motorola 68302 and the National HPC46400E microprocessors. The computer 50 runs an operating system 70 which supports one or more user application programs 72. Operating system 70 may include a communications manager 74, or the communications manager 74 may itself be an application program installed on the computer. In either case, the communications manager 74 controls a device driver 76 via the operating system 70. The device driver 76, in turn, communicates with the transceiver adapter 36 or 44 via bus interface 52. FIG. 3 shows one protocol which may be used in the preferred embodiment of the invention. It is to be appreciated that other protocols may be utilized in the practice of the invention. While the protocol is equally applicable to radio frequency (RF), infrared (IR), or wired transmission systems with broadcast capability, and to either conventional or spread-spectrum modulation techniques, slow-frequency hopped spread spectrum radio systems have a natural affinity for the protocol since those systems share a structure to time with the protocol. With reference to FIG. 3, there are five intervals defining a "hop". The first (and last) interval, G, is the interval during which the transmitter carrier frequency is changing. Note that the G interval is needed only for frequency hopping systems. The interval, X1, is the interval during which the base station broadcasts a special message to all the remote stations identifying the beginning of the following, or B, interval. The B interval is the interval during which, by convention, only the base station may initiate transmission and remote stations may respond only when required by the message protocol. For example, the remote station may acknowledge a message outbound from the base or may respond when polled. The B interval has a duration T1. The B interval is followed, in turn, by the X2 interval which is the interval during which the base station broadcasts a special message to all the remote stations identifying the end of the B interval and, by implication, the beginning of the C interval. The message also conveys the length of the C interval and, optionally, the length of the B interval as well. The X2 broadcast message is not strictly necessary. Information about the entire hop structure can be conveyed in the X1 interval. The X2 message is included to support operation of simplified remote stations capable of only contention-mode operation. These stations wait for the X2 message and contend subsequently. The C interval is the interval during which any station, including (or optionally excluding) the base station, may contend for the channel and transmit a message without the consent of the base station. For example, a CSMA/CA (carrier sense multiple access with collision avoidance) protocol may be used in this interval. The C interval duration is T2. If a remote station sends a message and receives an acknowledgement, it can assume the message has been received correctly. If not, it will contend again. There is a guard interval at the end of the C interval during which a remote station with a particular message may not transmit. If Tmsg is the time to transmit a particular message and Tack is the time to transmit an acknowledgement and Turnaround is the time between the end of a transmission of a message and the initiation of the transmission of an acknowledgement, then the guard interval is Tmsg+Tack+Turnaround. Note that because Tmsg is a function of the length of the message to be transmitted, the guard interval may be different for different remote stations having a message to send. The guard interval is not wasted; rather, messages and acknowledgements are sent and received right up to the end of the C interval. By varying the time T2, the base station can expand or contract the contention interval. If the system is very lightly loaded and most of the traffic is inbound to the base station, it is advantageous to remote response time to lengthen the time period T2. Conversely, if the system is heavily loaded and most of the traffic is outbound, the time period T2 should be minimized. The time period T2 should not be reduced to zero, however, as it is the only mechanism by which a newly activated remote station can register itself to the base station. Additionally, a further subdivision of the B interval, in which remote-to-base traffic is carried in allocated times lots, may be made as shown in FIG. 3A. In FIG. 3A, the B interval is subdivided into B1 and B2 subintervals, and the B2 subinterval is, in turn, subdivided into a plurality of time slots, each time slot being allocated to a specific remote station. Requests for an allocated slot may be made by a remote station in response to a poll during the B1 subinterval, or the requests may be made during the C interval. Once confirmed by a message from the base station, slot allocation guarantees that the remote station can transmit to the base station during its allocated time slot. By varying the boundary between the B2 subinterval and the C interval, the suitability of the system to different types of traffic can be adjusted. As the traffic load for steady, predictable traffic (e.g., real-time audio and video) increases, the boundary can be moved to lengthen the B2 subinterval and shorten the C interval, thereby increasing the number of allocatable time slots. Conversely, as the traffic becomes less predictable, the boundary can be moved to lengthen the C interval, providing greater bandwidth for contention-based traffic. From FIG. 3, it will be appreciated that the "hop" is divided into two subdivisions, one of which supports a controlled access scheme and the other of which supports a random access scheme. The invention may operate in any one of three modes: one in which only the X1 message is sent, one in which only the X2 message is sent, and one in which both are sent. In the case where only the X1 message is sent, the X1 message constitutes the header section of a frame. It identifies the start of the information frame, carries a unique identification of the base station, identifies the frequency hopping pattern, and defines the length of the B and C intervals. Optionally the Xl message also carries general broadcasting and system control information. In operation, each remote station waits for the X1 message. When received, a remote station sets an internal timer for T1 and for T1+T2 so that it knows when the contention interval begins and when to schedule its next frequency change. Broadcast reception of messages is not guaranteed, only likely. Radio conditions may be such that a particular remote station does not hear the broadcast message X1. Because a remote station cannot transmit autonomously without first hearing the X1 message and letting T1 elapse, it will remain quiet for the entire frame. Alternatively, if the remote station is polled by the base station during interval B, it may respond, but in no case can it contend in the C interval. It must remember T1+T2 from the last frame so that it knows when to hop, and it will listen in the next frame for the X1 message. If no X1 message is heard for a number of consecutive frames, the remote station must assume that it has lost hop synchronization with the rest of the system and enter a synchronization acquisition mode. Each frame time period of length T=T1+T2 can also be a frequency hopping period for implementation under FCC regulation part 15. A fixed length of time T is recommended but not necessary. A fixed length of time T is especially useful in the following cases: 1) When several frequency hopping patterns are used in overlapped operation in a multicell radio system, a fixed length of time T makes interference separation much more feasible. In this case, the frequency hopping pattern information in the header section can be used to identify the hopping sequence for a remote terminal to follow. 2) If all radios in a system are hopping with the same pattern, a fixed length of time T permits different cells to hop in synchronism but at different phases of the hopping pattern. This eliminates interference between cells. A tradeoff needs to be made in selecting the length of time T. A large time T makes the system overhead smaller, and a small time T makes the system response time smaller. Instead of the X1 message, the system can transmit the X2 message only. The content of the X2 message can be similar to that of the X1 message except that remote stations receiving the X2 message can immediately begin contention. This may be an advantage in some applications. For the case of transmitting the X2 message only, suppose the base station polls a remote station near the end of the B interval, and the remote station responds with a lengthy message. Generally, the protocol must prohibit these responses from being too lengthy. It may be that the response is active even as the period T1 expires. With only X1 messages, this may be a problem, but with X2 messages, the base station can then originate the X2 message as soon as the response is complete, making sure to include a shortened T2 period in the X2 message. The effect will be to diminish the contention interval for one hop's duration. In the third mode of operation, both X1 and X2 messages can be used to simplify the implementation of the remote station and to provide redundancy. The X1 message would then signal the beginning of the B interval, and the X2 message would signal the beginning of the C interval. Frequency Management This embodiment of the invention relates to methods and techniques for interference control in wireless LANs based on Slow Frequency Hopping Spread Spectrum communication. Specifically, interference control includes methods for accomplishing the following key steps in such a system. 1. FH Pattern Acquisition 2. FH Pattern Monitoring before Hopping 3. FH Pattern Revision Interference between adjacent cells in the system must be minimized, and preferably avoided altogether, by suitable FH pattern generation and assignment methods. In a multicell wireless LAN communications system, wireless cells are grouped into logical LANs, each logical LAN being controlled by a Wireless Network Controller 18 in FIG. 1A (WNC). The FH component of the Wireless Network Controller performs FH pattern management and control functions in a Logical LAN, for that purpose it is in communication with a wireless control agent (WCA) located in each base station. Each distinct Logical LAN is considered an autonomous network and carries a unique network identifier (NETWORK-ID). Two autonomous networks are distinct and independent entities that do not explicitly coordinate with each other. Two Logical LAN's or networks are collocated if radio coverage of one or more of the cells of one logical LAN can interfere with one or more of the cells of the other logical LAN. In this embodiment of the invention, each logical LAN includes a WNC and one or more Wireless Control Agents (WCA). Where the WNC and WCAs are physically situated, is a function of the type of the system. In a single cell wireless LAN system 80, such as shown in FIG. 4, a base station 82 includes both a WNC 84 and a WCA 88. The WNC is connected to a monitor 86 and the WCA 88. The WNC 84 and WCA 88 are together responsible for the distribution and maintenance of hopping patterns. The WNC 84 is a centralized managing station operating in a specified station, in this instance, base station 82. The WCA 88 is located in every base station in a logical LAN. In this instance since there is only one base station 82, it is in the same station as the WNC 84. As discussed below, this is not so in a multiple cell network. The WCA 88 is connected to a wireless adapter 90, which includes a radio control transceiver 92 for communicating with a plurality of remote stations. A remote station 94 includes a radio control transceiver 96 for communicating with radio control transceiver 92 in the wireless adapter 90 of base station 82. Remote stations 98 and 102 communicate in a like manner via radio control transceivers 100 and 104, respectively. FIG. 5 illustrates a multiple cell network 106 in which the WNC and WCA are in different physical units. In this instance, the WNC is a centralized managing entity operating in a specific station. The WNC may be in any terminal or station on a backbone LAN, whether it is a base station or not. For multi-segment LANS, there is a unique WNC for the whole network. This is true even for heterogeneous LANs including for instance token-ring and Ethernet segments as long as the network identifier is unique. The WCA is located in each base station linked to a backbone LAN, and acts as a representative of the WNC. The WCA functions as a cell controller and is responsible for opening the base station adapter for communication. As previously stated, the WNC and the WCA are responsible for the distribution and maintenance of the hopping patterns. The multiple cell network 106 of FIG. 5 includes a network station 108 which includes the WNC 110 which communicates with a monitor 112 and a backbone adapter 114 which is connected to a backbone LAN 116. The WNC 110 has access to a network control database 109 comprising network topology and frequency management information. It is seen that the network station 108 does not include a WCA. A plurality of base stations, each of which includes a WCA, is connected to the LAN 116. For example, base stations 118 and 120 are connected to the LAN 116. When two base stations have overlapping geographical coverage areas they are called neighbors. This means that in these overlap areas, a given remote station can receive signal from both neighbor base stations. Base station 118 includes a WCA 122 which communicates with the WNC 110 of network station 108 via LAN 116, and with wireless adapter 124 which includes a radio control transceiver 126. The transceiver 126 communicates with a plurality of remote stations 128, 132 and 136 which include radio control transceivers 130, 134 and 138, respectively. Base station 120 includes a WCA 138 which communicates with the WNC 110 of network station 108 via LAN 116, and with wireless adapter 140 which includes a radio control transceiver 142. The transceiver 142 communicates with a plurality of remote stations 144, 148 and 152 which include radio control transceivers 146, 150 and 154, respectively. How FH pattern acquisition; monitoring before hopping; and pattern revision is accomplished in a given logical network such as those set forth in FIGS. 4 and 5 is set forth below. FIG. 6 is a flow chart which provides an overview of Frequency Hopping operation in a single Logical LAN. When a base station is powered on at block 160 it must first acquire a FH pattern to use in the cell as shown at block 162. This is accomplished by sending a request and then receiving a FH pattern in response from the Wireless Network Controller. The base monitors its radio environment at block 164 to ensure that no other base within its radio vicinity is using the same FH pattern. Then it starts frequency hopping at block 166. It also communicates the FH pattern to remote stations within its range. Remote stations perform monitoring of interference on the hops in a FH pattern. The base station monitors interference on the FH pattern at block 168. At block 170, it is determined if FH pattern revision is necessary. If revision is necessary as determined at block 172, a return is made to block 164. If revision is not necessary, hopping is continued with the same pattern at block 174, and a return is made to block 168. Details of the various steps are described below. Only frequency-hopping pattern management within a single Logical LAN is considered. The base stations in a Logical LAN operate in an "unsynchronized" manner. Each base station follows a cyclic frequency hopping pattern. One period of this cyclic hopping pattern structure is called a "superframe". Superframes of adjacent base stations satisfy the following conditions. 1. All the hops within a superframe have the same length. 2. All the base stations have the same number of hops within a superframe. 3. Superframes of adjacent base stations are not synchronized. FIG. 7 illustrates a superframe comprised of M Hops. There are M used hops at any given time, and N-M unused hops, where M is an integer which is less than the total number of available hopping frequencies N (M<N). How a hopping pattern is acquired by a base station is explained below. FIG. 8 illustrates an example of a frequency band (83 MHZ wide) divided into 83 available channels each 1 MHZ wide. A subset of the channels can be chosen to form a FH pattern. Each hop is one megahertz (1 MHZ) wide, and the frequencies entered from 2.400 gigahertz (GHZ) to 2.482 (GHZ). It is to be appreciated that a different frequency band may be utilized in the practice of the invention. In practice, different countries have different rules governing the frequency bands that may be utilized. As is known in the art, data is modulated on the carrier frequencies (hopping frequencies) for transmission between base stations and remote stations. Frequency Hopping Pattern Acquisition The overall logic for Frequency-Hopping operation in a logical LAN was described relative to FIG. 6. An outline of the acquisition of FH patterns by a base station is as follows. Consider a Logical LAN with multiple base stations. When a requesting base station is powered on, it sends a Hopping Pattern Request (HPR) packet to the Wireless Network Controller. FIG. 9 shows the structure of a HPR packet the first field carries a predetermined code indicating that it is a frequency hopping pattern request, the next field carries the identifier assigned to the base station requesting a FH pattern and the last field carries the identifier of the logical network the requesting base station wants to register in. According to the present invention, on receipt of a Hopping Pattern Request packet, the Wireless Network Controller executes the following steps as shown in FIG. 10. A determination is made at block 180 if all FH patterns from the set of possible patterns have already been assigned to active base stations belonging to the same logical network as the requesting base station. If so the process jumps to block 181 to reuse a FH pattern according to a method further explained below in relation with FIG. 13. If not, the process randomly selects a FH pattern from the set (FHPSET) of patterns at block 182 among those which have not been assigned. The Wireless Network Controller keeps track of FH patterns that are being used by the base stations belonging to the logical network it controls as shown in block 183. At block 184 the process communicates to the base station the resulting FH pattern. This communication occurs via the backbone communication network . The FH pattern information is contained in response to a hopping pattern request (HPR) message as shown in FIG. 11, the first field carries a predetermined code indicating that it is response to a hopping pattern request, the next field carries the identifier of the Wireless Network Manager answering the hopping pattern request and the last field carries the FH pattern assigned to the requesting base station. On receipt of the message, the requesting base station immediately starts hopping with its newly assigned FH pattern. The same steps (176 to 184, FIG. 10) are performed upon request from a base station which detects that another base is using the same FH pattern as shown in step 164 FIG. 6. Frequency Hopping Pattern Reuse Referring now to block 181, it is performed by the Wireless Network Controller when all existing patterns have already been assigned to active base stations belonging to the same logical network as the requesting base station. One object of the invention is to provide a method for reusing frequency hopping patterns when all possible patterns have already been assigned to active base stations as will be describe in detail in reference to FIG. 13. Such a method involves information gathered by the Wireless Network Controller 110 (FIG. 5) in the centralized network control data base 109 whose structure is going to be described hereafter. Referring now to FIG. 12 it shows the contents and structure of the wireless LAN control database 109 (FIG. 5) used in this embodiment of the invention. The network resident data table 210 (FIG. 12) holds the network attributes common to all the stations of a given logical LAN. The NETWORK -- ID parameter identifies a given logical wireless LAN among other collocated logical LANs. The country code identifies the nation in which the system operates and is necessary to conform with the regulations set in each country to control the operation of mobile systems and more particularly RF systems. Some kind of security key information is also necessary to prevent that unauthorized users may join the network or monitor the data traffic. Other network options such as access control type also has to be stored in the network resident data table and shared with all the stations. Frequency management information is provided in the frequency hopping patterns table 250. The frequency hopping patterns table 250 lists all the frequency hopping patterns available in the country where the system operates. In the example provided in FIG. 12 there are 78 patterns (FHP1 to FHP78) each pattern consisting in a unique sequence of the M used frequencies of FIG. 7 (HOP1 . . . HOPM). For instance frequency hopping pattern FHPk consists in the sequence of M frequencies f(k,1) . . . f(k,M) which is a unique sequence of the M used frequencies HOP1. . . HOPM. Each entry in the frequency hopping patterns table comprises a first field carrying frequency hopping patterns identifiers (FHP1 to FHP78) followed by the sequence of M frequencies constituting the frequency hopping pattern, for instance f(k,1) to f(k,M) is the sequence corresponding to FHPk. Each entry also comprise an additional field (not shown in FIG. 12) indicating whether the corresponding FH pattern is assigned to an active base station, this information is used by the network controller when looking for a free FH pattern at step 10 of FIG. 10. These patterns are not static, they are updated each time a new interference situation is faced and the new information is automatically provided to all the active base stations of the logical wireless LAN network. If single frequency channels are used, the frequency management information would consist in a list of frequencies. If direct sequence spread spectrum is used the frequency management information contains the list of all available chip codes. The network topology directory table 230 lists all the base stations which form the logical LAN and carries a list of parameters assigned to each base station. It also keeps track of information representative of the radio topology of the wireless LAN system and more specifically it holds a list of direct neighbor base stations for each base station belonging to the logical wireless LAN. There is one entry for each base station defined in the logical wireless LAN system, each entry comprises: n: table direct access index. BS -- NAME(n): the base station name, typically a unique string of characters. BS -- NETWORK -- ADDRESS(n): the base station network address, which is used to establish the connection between the base station and the wireless network station 108 over the LAN backbone, 116 in FIG. 5. BASE -- ID(n): identifier assigned by the wireless network controller to the base station, it is used by the remote stations to identify the different base stations. CELL -- FHP(n): frequency hopping pattern used by the base station. EMITTED -- POWER(n): base station emitted power, provided at network setup time by the operator and adjusted subsequently according to traffic load. BASE -- STATUS(n): indicates whether the base is active or inactive. BASE-ID(1), 1: list of base stations which are direct neighbors of BASE -- ID(n) comprising their identifiers BASE -- ID(l) along with the direct access index 1 pointing to the corresponding entry in the network topology directory. In the example shown in FIG. 12 it is assumed that the frequency hopping pattern CELL -- FHP(n) assigned to the base station BASE -- ID(n) is FHPk and similarly FHPj is used by BASE -- ID(n+1). In order to be allowed to register in a given logical wireless LAN system, a base station must be defined in the network topology directory 230 with its network address on the LAN backbone. This is defined by the network operator at network set-up time. At network set-up time, the network operator also provides for each base station the list of other neighboring base stations, based on the physical set-up of the system and taking into account interference measurements performed as part of the network planning and installation procedure. Defining a new base adds an entry in the network topology directory. At start-up time the base station requests its operating parameters from the wireless network controller 110 through the LAN backbone 116. The operating parameters include the network identifier (NETWORK -- ID), the country code, the network options, the base station identifier (BASE -- ID), the frequency hopping pattern assigned to the base station (CELL -- FHP) and the base station emitted power. The network identifier, the country code, the network options and the base station emitted power are those provided at network setup time by the operator. The base station identifier and the frequency hopping pattern may be assigned in different manners. A first approach is to simply keep track of the base station identifiers and frequency hopping patterns that have been already assigned and to select randomly among those which are still available. Such a method limits the number of base stations in a given wireless LAN system to the maximum number of base station identifiers or to the maximum number of frequency hopping patterns available in the country where the system operates. In the system carrying out this embodiment of the invention the maximum number of base stations identifiers is 64 and the maximum number of frequency hopping patterns vary from around 60 to 80 depending on the various country regulations. One object of this invention is to overcome these limits by reusing already assigned frequency hopping patterns. The method of the invention uses information about neighboring stations from the network topology database to derive an indication of radio cell distance between the various base stations as described in detail below. Referring now to FIG. 13, it shows a flow diagram of the method used for reusing frequency hopping patterns. In step 310 the wireless network controller looks-up in the frequency hopping patterns table 250 for a free FH pattern. If it finds one the process jumps directly to step 360 FIG. 13A as shown by connector B and the available FH pattern is returned to the requesting base station. If all FH patterns have already been assigned the process prepares at step 315 a distance table with a first column consisting in the list of all existing FH patterns identifiers (FHP1 to FHP78), a second column for storing the identifier of the base station using the FH pattern of the first column and a third column for storing an integer value D representative of the distance between the requesting base station and the base station of the second column. The initial value of D is set to a maximum value MAX for all entries of the distance table. At step 320 the process looks up in the network topology table 230 for the entry corresponding to the requesting base station identified by its BASE -- ID. Based on the list of neighbor base stations and the direct access index of the corresponding entry in the network topology table the process retrieves the assigned FH pattern and the status of each neighbor base station. For those neighbor base stations whose status is active, the process updates the entry in the distance table corresponding to their assigned FH with the neighbor base station identifier BASE -- ID and sets the value D of the corresponding distance to 1. As a result of step 320, all the direct neighbors of the requesting base station are included in the distance table and the value of the distance D between the requesting base station and its direct neighbors is set to 1. Step 325 is similar to step 320, the process updates distance table entries corresponding to FH patterns assigned to those second level neighbors whose status is active. Second level neighbors are direct neighbors of the requesting base station's direct neighbors. Each entry carries the FH pattern assigned to the corresponding second level neighbor and the second level neighbor base station identifier. For these entries, the value of the distance D is set to 2. It should be noted that a second level neighbor may have already been identified as a direct neighbor, in such a case it is not processed as a second level neighbor and the value of the distance D is kept to 1. The same processing as step 325 is repeated in step 330 for third level neighbors, i.e. direct neighbors of second level neighbors. As a result of step 330, the distance table entries corresponding to the direct, second level and third level neighbors FH patterns carry the neighbor base stations identifiers and the value of the distance D has been set respectively to 1, 2 and 3 for those table entries. Assuming that a frequency hopping pattern has been requested by the base station BASE -- ID(m) and using the tables of FIG. 12, the distance table will, as a result of step 330, look as follows: TABLE 1______________________________________FH pattern Base stationidentifier identifier Distance value D______________________________________FHP1 MAX. . . . . . . . .FHPk BASE.sub.-- ID(n) 1. . . . . . . . .FHPj BASE.sub.-- ID(n + 1) 2. . . . . . . . .FHPi BASE-ID(q) 3. . . . . . . . .FHP78 BASE.sub.-- ID(p) 3______________________________________ This table assumes that BASE -- ID(n) is a direct neighbor of BASE -- ID(m) therefore the entry corresponding to its FH pattern FHPk is assigned a distance value D of 1. BASE -- ID(n+1) is a direct neighbor of BASE -- ID(n) and a second level neighbor of BASE -- ID(m) , the entry corresponding to its FH pattern FHPj is assigned a distance value D of 2. BASE -- ID(p) and BASE -- ID(q) are direct neighbors of BASE -- ID(n+1) and third level neighbors of BASE -- ID(m), the entries corresponding their FH patterns (supposedly FHPi and FHP78) are assigned a distance value of 3. This table assumes that FHP1 is not assigned to any direct, second or third level neighbor of BASE -- ID(m), therefore the corresponding distance value D is kept to MAX. The process goes on with step 335 in FIG. 13A as shown by connector A. The process looks up in the distance table for an entry whose distance value D is MAX which means that the corresponding FH pattern is not used by either a direct, a second level or a third level neighbor. If there are such entries, the process goes on with step 340 similar to step 325, to include 4th level neighbors in the distance table and set their distance D to 4. If all FH patterns have been assigned a distance value D of either 1, 2 or 3, the process selects in step 355 one of the FH patterns with a distance D of 3 and returns it to the requesting base station in step 360. In step 345 the process looks up again in the distance table for an entry with a distance D of MAX. If there are remaining FH patterns with a distance of MAX the process selects one of them in step 350 and returns it to the requesting base station in step 360. If all FH patterns have been assigned a distance value D of 4 or less the process selects in step 355 one of the FH patterns with a distance D of 4 and returns it to the requesting base in step 360. It should be noted that the method described in the flow diagrams of FIG. 13 and 13A are merely illustrative of the invention. The man skilled in the art can easily adapt this method to fit particular performance requirements or interference situations. One alternative is for instance to perform the processing of steps 325, 330 and 340 for 5th level neighbors and above until all direct and indirect neighbors are found and to select either one of the remaining FH patterns with a distance of MAX or, if no such remaining FH pattern is left, one of the FH patterns with the greatest distance value D. Intercell Interference Learning The topology information provided by the network operator at network set-up time about neighboring relationships between base stations is subject to change through time. Such changes may come from various reasons: base stations may be physically moved, their emitted power may be modified thus changing the size of the wireless LAN cells, or radio frequency propagation conditions may change due for instance to modifications made to the building where the wireless LAN is installed. One aspect of the invention is to provide a method for dynamically updating base stations neighboring relationships information. Information about cells overlaps is gathered by remote stations when they register with a given logical LAN and is sent to the corresponding WNC for update of the network topology table. In the system used in the preferred embodiment of the invention there is no synchronization between the base stations of a given logical LAN. Each base simply maintains a fixed length superframe structure and operates independently of other bases. In the preferred embodiment a superframe consists of 75 frequency hops, each hop corresponding to a 50 milliseconds frame. As a result a superframe lasts for 3.75 seconds. At the beginning of each frame each base station sends the X1 message. The X1 message constitutes the header section of a frame, it identifies the start of the information frame, it carries a unique identification of the base station comprising the base station identifier BASE -- ID and the logical LAN identifier NETWORK -- ID. When a remote station is powered on it does not know who are the surrounding base stations and which frequency hopping patterns they use. It only knows the frame and superframe durations and the set of all possible frequencies used by the base stations. To register with a target logical LAN, the remote station starts by randomly selecting a frequency and listening for X1 messages from neighboring base stations. After a fixed period of time, it switches to another frequency and keeps listening for X1 messages. Upon receipt of a X1 message carrying the NETWORK -- ID of the target logical LAN, the remote station records in a base station selection table, the identifier of the emitting base station BASE -- ID, its HDLC address and an indicator representing the strength of the signal received from the emitting base station. A number of frequencies is scanned for selecting a home base station belonging to the selected logical LAN, as a result of this scanning process the remote station builds a base station selection table from which it selects the base station with the strongest signal. Such selection may further involve listening to a given base station's signal at various frequencies to compute an average signal strength indicator taking into account frequency dependent fading conditions. The registering remote station sends a registration request packet to the selected base station carrying the list of the base station identifiers recorded in its selection table. This list is transmitted to the wireless network controller (WNC) by the wireless control agent (WCA) of the selected base station and is added to the list of neighbor base stations in the network topology directory entries corresponding to each one of the base station identifiers recorded in the selection table. Thus the network topology table is periodically updated by neighboring information provided by registering remote stations. Gathering such information relative to base stations overlaps can also be performed by active remote stations on a periodic basis and reported to the wireless network controller in a way similar to what has been described for registering base stations. While the preferred embodiment of the invention relates to frequency hopping patterns assignment and more specifically frequency hopping patterns reuse. The method of the invention is applicable to reuse and assign to a requesting base station other network resources such as for instance base stations identifiers. When utilized for reusing base stations identifiers BASE -- ID the method of the invention comprises building a distance table of the form: TABLE 2______________________________________Base stationidentifier Base Station name Distance value D______________________________________BASE.sub.-- ID1 BASE.sub.-- NAME(i) MAX. . . . . . . . .BASE.sub.-- ID2 BASE.sub.-- NAME(j) 3. . . . . . . . .BASE.sub.-- ID3 BASE.sub.-- NAME(k) 1. . . . . . . . .BASE.sub.-- IDm BASE.sub.-- NAME(l) MAX. . . . . . . . .BASE.sub.-- IDn BASE.sub.-- ID(p) 2______________________________________ The first column of this distance table lists all the base stations identifiers used in the logical LAN, BASE -- ID1 to BASE -- IDn, the next column carries a unique base station identifier, in this particular example the base station name BASE -- NAME() is assumed to provide such a unique base station identifier, the third column carries the distance value D. Assuming that this distance table carries distances to a requesting base station whose name is BASE -- NAME(m), the first line in this table indicates that BASE -- NAME(i) is not a direct nor indirect neighbor of BASE -- NAME(m) and that BASE -- NAME(i) has been assigned BASE -- ID1 as base station identifier BASE -- ID()in the network topology table 230. Therefore BASE -- ID1 can be reused by BASE -- NAME (m). Similarly, the next line indicates that BASE -- ID2 has been assigned to BASE -- NAME(j) and that BASE NAME(j) is a third level neighbor of BASE -- ID(m). The method used to build this distance table follows the same logic flow as the method described above in relation to FIG. 13 and 13A wherein base stations identifiers (BASE -- ID) are substituted to frequency hopping patterns and base station names (BASE -- NAME) are substituted to base stations identifiers as shown in FIG. 14 and 14A. In step 410 the network controller looks for a free BASE -- ID. If there is no free FHP it prepares in step 415 the distance table of Table 2 and sets all values of distance D to a maximum value MAX. In step 420 the process updates distance table entries corresponding to first level neighbors of the requesting base station. For those first level neighbor base stations whose status is active, the process updates the entry in the distance table corresponding to their assigned BASE -- ID with the first level neighbor unique name BASE -- NAME and sets the value of D to 1. Step 425 is similar to step 420, the network controller updates distance table entries corresponding to the base stations identifiers BASE -- ID assigned to second level neighbors with the second level neighbor BASE -- NAME and set the corresponding distance D to 2. Step 430 updates the distance table for third level neighbors. In step 435 (FIG. 13A) the network controller looks up in the distance table for entries with a distance value of MAX. If all entries have distance values of 1, 2 or 3 the process selects in step 455 a BASE -- ID associated with an entry with a distance of 3. It there are remaining entries with a distance of MAX the network controller updates in step 440 table entries corresponding to fourth level neighbors. Steps 445, 450, 455 and 460 perform the same processing as steps 345, 350, 355 and 360 in FIG. 13A wherein BASE -- ID's are substituted to FH patterns. While the system carrying out the preferred embodiment of the invention uses frequency hopping radio signaling, the method of the invention can be practiced on other kinds of wireless communication systems such as infrared (IR) systems.
In a wireless communication system (106), base stations (118, 120) are connected to a backbone network (116) such as a wired LAN and act as access points and relays for remote stations (128, 132, 136). A remote station registers and performs bidirectional communication with one of the base stations designated as its home base station. Base stations have overlapping coverage areas where a remote station is within reception range of several base stations. Such communication system may for instance be a multicell radioLAN using frequency hopping signaling. The method allows reuse of a limited number of network resources such as frequency hopping patterns and assign the same resource to several active base stations. Upon request from a base station, a network controller (110) connected to the backbone network computes a distance index between the requesting base station and the other active base stations and assigns to the requesting base station the same network resource as the one assigned to another base station with the highest distance index. Information about cells overlaps is centralized in a control database (109) and used by the network controller to compute distance indexes.
7
BACKGROUND OF THE INVENTION 1. Technical Field The present invention relates to a fiber composite twisted cable and, more specifically, to a twisted cable in which carbon fibers and thermosetting resin as a matrix are combined. 2. Description of the Related Art Among high-strength low ductility fibers, carbon fibers have characteristics such as light weight, high corrosion resistivity, non-magnetic property, high coefficient of thermal conductivity, ultralow coefficient of thermal expansion, high tensile strength, and high tension modulus. In order to make full use of such characteristics, a fiber composite twisted cable having carbon fibers and thermosetting resin as a matrix combined to each other is known. The fiber composite twisted cable is manufactured generally by forming strands by twisting bundles of carbon fibers impregnated with thermosetting resin, twisting a plurality of such strands, and then curing the thermosetting resin by heat treatment. However, there is a problem such that air or residual solvent contained in thermosetting resin remains in the interior of a cable as gaps between a process of impregnating with the thermosetting resin and a process of forming a cable by twisting the plurality of strands, whereby mechanical characteristics such as the tensile strength per cross-sectional area of the cable, which is important characteristics as the fiber composite twisted cable is lowered. Accordingly, in JP-A-2-127583, a fiber composite twisted cable formed by winding a fiber yarn on an outer periphery of a strand impregnated with thermosetting resin at an angle close to a right angle with respect to the axial direction of the strand in high density, then twisting a plurality of the strands, and then curing the thermosetting resin by heat treatment is proposed. According to the related art, the fiber bundles are prevented from being unlaid by winding the fiber yarn, and an effect of expelling the air or the residual solvent contained in the interior of the cable is expected by a winding pressure of the fiber yarn. However, when twisting the plurality of strands impregnated with the thermosetting resin, liquid-state thermosetting resin in an uncured state is squeezed out from between the wound fiber yarns, so that the resins from adjacent side strands moisten with respect to each other, and flows into a gap between a core strand and the side strands and stays therein. Therefore, when the thermosetting resin is cured in a last process, the adjacent strands are adhered and integrated with each other (the core strand and the side strands, and the side strands and the side strands), so that the entire cable becomes cured like a hard rod. Therefore, bending rigidity of the fiber composite twisted cables in the related art is very high and, consequently, flexibility that the cable should have under normal circumstances by having a twisted wire structure is impaired, and hence a large reel provided with a large-diameter winding barrel is required. Consequently, when applying the fiber composite twisted cable to a reinforcing member for an overhead transmission line and performing a wiring work in a mountain range for example, problems in transport such that a large vehicle for loading the large reel is required and, road works for moving the large vehicle in turn are required are inevitable. Furthermore, when winding the fiber composite twisted cable on the reel, partial separation of the thermosetting resin which bonds the strands with respect to each other occurs by bending, so that bonded portions and separated portions exist together between the adjacent strands in the longitudinal direction of the cable. Consequently, there arises a problem such that bending occurs when the cable is withdrawn from the reel when using the cable and hence linearity of the cable is impaired. SUMMARY OF THE INVENTION In order to solve the above-described problems as described above, the fiber composite twisted table in the related art is improved, and it is an object of the invention to provide a fiber composite twisted cable having preferable flexibility and being superior in transportability and workability suitable for being used as a reinforcing member for a high-voltage transmission line or a tensile strength reinforcing member for concrete structures such as a bridge girder. In order to achieve the above described object, a fiber composite twisted cable according to an embodiment of the invention is a cable having 1×n structure which is formed by impregnating bundles of carbon fibers with thermosetting resin, then twisting a plurality of strands each formed by covering an outer periphery of the bundle with a fiber, and then curing the thermosetting resin by heat treatment, and is characterized in that a core strand and side strands surrounding the same, which constitute the 1×n structure, are in contact with each other separately and independently without being bonded to each other so as to allow the respective strands to perform independent behaviors when the cable is bent at a right angle with respect to the longitudinal direction. With the fiber composite twisted cable according to the invention, the respective strands which constitute the cable are separately and independently in contact with each other without being bonded to each other, and minute gaps for allowing the independent behaviors when the cable is bent in the direction at a right angle with respect to the longitudinal direction thereof are formed between the core strand and the side strands surrounding the same. Therefore, a constraining force is suitably alleviated by a slipping effect between the adjacent strands, whereby the flexibility required for the cable is improved. Since deformation of the strands due to a bending stress applied to the cable is facilitated by the gaps surrounded by the side strands and the core strand secured therein, the flexibility is further improved. Therefore, according to the embodiment of the invention, since the flexibility of the cable is improved, winding of the cable around the reel, which is inevitable when manufacturing a long cable or transporting the cable as a product, can be performed without problem, and the barrel diameter of the reel can also be reduced. Therefore, when it is used as the reinforcing member for the high-voltage transmission line or the tensile strength reinforcing member for the concrete structure such as a bridge girder, transport of the cable to the mountain range or the mountain area is facilitated, and a transport cost can be reduced. Since the cable can be wound around the reel without problem, generation of abnormal residual stress on the cable is avoided, and formation of curl is avoided even when the cable is withdrawn from the reel when using the same. The cable withdrawn from the reel is easy to handle, allows measurement of the cable length with high degree of accuracy on site, and allows easy terminal process. Therefore, the workability is improved. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1A is a perspective view showing a first embodiment of a fiber composite twisted cable according to the invention; FIG. 1B is a vertical cross-sectional front view of the first embodiment; FIG. 1C is a partial enlarged view of FIG. 1B ; FIG. 2A is a perspective view showing a state in which the fiber composite twisted cable according to the first embodiment is about to be put asunder; FIG. 2B is a perspective view of the fiber composite twisted cable shown in FIG. 2A after having put asunder; FIG. 3 is an explanatory drawing showing a process of manufacturing a prepreg by impregnating a multifilament formed of carbon fibers with thermosetting resin; FIG. 4 is an explanatory drawing showing a process of manufacturing a covered composite strand; FIG. 5 is an explanatory drawing showing a process of manufacturing a composite twisted cable in a semi-cured or uncured state by twisting the covered composite strands; FIG. 6 is an explanatory drawing showing a heat treatment process; FIG. 7A is a perspective view showing a fiber composite twisted cable after having finished the heat treatment; FIG. 7B is a cross-sectional view of the fiber composite twisted cable after having finished the heat treatment; FIG. 7C is a partial enlarged view of FIG. 7B ; FIG. 8A is a side view showing an apparatus and a process of separating the strands of the fiber composite twisted cable; FIG. 8B is a cross-sectional view taken along the line X-X in FIG. 8A ; FIG. 9A is a perspective view showing a second embodiment of a fiber composite twisted cable according to the invention; FIG. 9B is a cross-sectional view showing a state before strand separation according to the second embodiment; FIG. 10A is a perspective view showing a third embodiment of a fiber composite twisted cable according to the invention; FIG. 10B is a cross-sectional view showing a state before strand separation according to the third embodiment; FIG. 11A is a drawing of a state in which power cables are strung showing an example in which the fiber composite twisted cable according to the embodiment of the invention is applied to a reinforcing member of the a high-voltage transmission line; FIG. 11B is a partially cut-out side view of the power cable shown in FIG. 11A ; FIG. 11C is a cross-sectional view of the power cable shown in FIG. 11B ; FIG. 12A is a perspective view of a bottom of a bridge showing an example in which the fiber composite twisted cables according to the embodiment of the invention are applied to tensile strength reinforcing members of a concrete bridge girder; and FIG. 12B is a bottom view of the bridge girder in a tensed state. DETAILED DESCRIPTION OF THE INVENTION Referring now to the attached drawings, an embodiment of the present invention will be described. FIG. 1A to FIG. 2B show a fiber composite twisted cable having 1×7 structure according to an embodiment of the invention. Reference numeral 1 designates an entire fiber composite twisted cable (hereinafter, referred to simply as “cable”), having a diameter of 12 mm, for example. Reference numerals 21 , 22 are strands which constitute the cable 1 . The cable 1 includes seven strands having the same thickness. Six side strands 22 are arranged around a single core strand 21 , and these strands are twisted together. The core strand 21 and the side strands 22 are formed by binding or twisting a plurality of prepregs 2 ′, which are formed by impregnating respective bundles of PAN (polyacrylonitrile) carbon fibers 2 with thermosetting resin 3 as shown in FIG. 1C . Also, the outer periphery of the each strand is covered with a fiber yarn 4 wound therearound at an angle close to a right angle with respect to the axial direction of the strand in the high density. The “yarn” here is a concept including a tape. The core strand 21 and the six side strands 22 are covered with the fibers, and are twisted with the thermosetting resin contained therein uncured and hence are formed into the uncured fiber composite twisted cable. Then, the uncured fiber composite twisted cable is subjected to heat treatment so that the thermosetting resin is cured. However, in the embodiment of the invention, the adjacent side strands 22 and 22 are not bonded to each other, and the side strands 22 and the core strand 21 are not bonded to each other, that is, the respective strands are separated and independent and are only in contact with each other in the longitudinal direction. Therefore, five gaps 5 in substantially a triangle shape, where the thermosetting resin is not present, are formed in a portion surrounded by the core strand 21 and the two side strands 22 and 22 in the embodiment as shown in FIG. 1B , and the gaps 5 function as spaces for allowing independent behaviors of the strands when the cable is bent in the direction at a right angle with respect to the longitudinal direction. FIGS. 2A and 2B show the fiber composite twisted cable being put asunder. The single core strand 21 at the center and the six side strands 22 positioned therearound exist separately and independently respectively at a regular helical pitch. The separate and independent relationship between the core strand 21 an the side strands 22 is realized by performing a separation process which forcedly releases a bonded state of the respective strands after the heat treatment, that is, after having cured the thermosetting resin. More specifically, in a manufacturing process, the core strand 21 and the six side strands 22 are twisted in the state in which the thermosetting resin contained therein is uncured or semi-cured. The thermosetting resin is extruded out from between the fiber yarns 4 on the outer peripheries of the respective strands by a pressure applied by this twisting action, and wets the adjacent side strands 22 with respect to each other. It also wets the periphery of the core strand 21 , so that the gaps around the side strands 22 and the core strand 21 are filled with the thermosetting resin. In this state, heat is applied and the thermosetting resin is cured, so that the adjacent side strands 22 and 22 are integrally bonded to each other and the side strands 22 and 22 and the core strand 21 are also bonded to each other. Normally, the fiber composite twisted cable is considered to be a finished product in the state described above. However, according to the embodiment of the invention, the integrally bonded side strands 22 and 22 , and the side strands 22 and 22 and the core strand 21 are separated after the heat treatment into independent individual strands and, in this state, these strands are twisted again into the original state. The separating process is performed after the thermosetting resin is cured and stabilized. Therefore, the adjacent side strands 22 and 22 and the core strand 21 are never bonded to each other again. Since the core strand 21 and the side strands 22 are separated and independent, when a bending stress is applied to the cable 1 , the side strands 22 can be moved in their own about the core strand 21 . Therefore, bending rigidity is smaller than that of a bar (rod) having the same diameter, so that higher flexibility is resulted. Since the substantially triangle gap 5 per unit, which is surrounded by the core strand 21 and the two side strands 22 and 22 allow the side strands 22 to run off on the tensed side and the compressed side when being bent. Therefore, the cable 1 can easily be bent and the residual stress is also alleviated. Subsequently, the manufacturing process of the fiber composite twisted cable 1 according to an embodiment of the invention will be described in detail. FIG. 3 shows a process for obtaining the strand. A multifilament 30 including 12000 carbon fibers having a diameter of 7 μm, for example, and being aligned in parallel are wound around a reel 31 . The multifilament 30 is withdrawn from the reel 31 , is guided to a resin bath 35 via a guide roll 32 , and is allowed to submerge through the thermosetting resin 3 , for example, modified epoxy resin, stored therein, and the multifilament 30 is impregnated with the modified epoxy resin. The multifilament 30 impregnated with the modified epoxy resin is introduced into a dice 33 , and excessive modified epoxy resin is pressed and removed, and is formed into a circular shape in cross-section. Then, the multifilament 30 is passed through a drying furnace 36 to semi-cure the thermosetting resin to form a prepreg (element wire) 38 , which is wound around a reel 39 . The prepreg may be kept in uncured state by omitting or stopping operation of the drying furnace 36 . Subsequently, a number of, for example, fifteen prepregs 38 manufactured in the previous process, not shown, are bundled and twisted at a large pitch, for example, 90 mm, so that a composite element strand is obtained. In this process, for example, fifteen reels 39 having the prepreg 38 wound therearound are arranged on a stand, the fifteen prepregs are withdrawn and bundled into the composite element strand and are twisted by turning the reel in the direction at a right angle with respect to a movement path while winding the same together on a reel. The modified epoxy resin is used when the heat resistance on the order of 130° is required. When the heat resistance as high as 240° is required, Bismaleimide resin is used. FIG. 4 shows a formation of the strand and a covering process, in which reference sign b designates a covering device. A reel 40 having a composite element strand 381 manufactured in the previous process wound therearound is mounted on a supporting shaft 401 of the covering device b. The covering device b is provided with a winding machine 45 around the movement path of the composite element strand, and the fiber yarn 4 is wound around the winding machine 45 . Multifilament yarn formed of multipurpose fiber such as polyester fiber is suitable as the fiber yarn and, for example, that having 8 yarns of 1000 denier is exemplified. The composite element strand 381 is wound by a strand reel 49 via a guide roll 42 , and the winding machine 45 is turned around the composite element strand 381 in the course of movement to wind the fiber yarn 4 on an outer periphery of the composite element strand 381 to cover the outer periphery at an angle close to a right angle with respect to the axial direction, for example, at 60 to 85 degrees in the high density. Consequently, a covered composite strand 50 is manufactured. The purpose for covering the periphery of the strand with the fiber is to bundle the composite element strand 381 and prevent the same from being deformed or unlaid at the time of twisting. Another purpose is to discharge and remove the excessive thermosetting resin or solvent which the strands are impregnated with, or air bubbles which may cause the strength of the cable to be lowered or the like by a winding pressure. Subsequently, the seven strand reels on which the covered composite strands 50 are wound are mounted on a twisting device c shown in FIG. 5 . The twisting device c includes one strand reel 491 on which a strand which becomes the core strand is wound, and six strand reels 492 on which strands which become the side strands arranged therearound. The six strand reels 492 for the side strands are rotated around the single composite strand 50 which becomes the core strand, the six covered composite strands 50 ′ which become the side strands are twisted and are passed through a voice 51 while being pulled by a capstan 52 , so that the thermosetting resin is wound around a reel 59 as a composite twisted cable 60 in the state in which the thermosetting resin is semi-cured or uncured. Subsequently, the reel 59 on which the uncured composite twisted cable 60 is wound is arranged in a heat treatment device d shown in FIG. 6 , and the uncured composite twisted cable 60 is passed through a heater 65 under the conditions of, for example, 130° C. and 90 minutes, the semi-cured or uncured thermosetting resin is completely cured, and a cured composite twisted cable 90 is wound around a reel 69 . A semi-cured or uncured thermosetting resin 300 contained in the composite strand of the cured composite twisted cable 90 is exuded from the gaps between the fiber yarns in the initial stage of heating. The respective gaps surrounded by a core strand 91 and side strands 92 , 92 is filled with the exuded thermosetting resin 300 and the thermosetting resin 300 filled in the respective gaps is cured in the latter half of the heating period. Therefore, as shown in FIG. 7A to FIG. 7C , the core strand 91 and the side strands 92 are integrally bonded. Since the troughs between the adjacent side strands 92 , 92 are also filled with the thermosetting resin 300 , the side strands 92 , 92 are also bonded to each other. The form as described above is unavoidable in the fiber composite twisted cable in the related art. The inventors thought of applying the heat treatment on the composite strands 50 , 50 ′ manufactured in the process shown in FIG. 4 , forming the strands whose thermosetting resin contained therein is cured, and twisting these hard covered strands into a cable as a measure for improving the flexibility. However, since the hard covered strands are already in the state of hard rods, it is very difficult to bundle seven such hard strands and twist the same into the helical shape. In addition, since the thermosetting resin in the strands is separated during twisting and hence the function as the matrix is impaired, it is not suitable. Accordingly, in the invention, the core strand 91 and the side strands 92 , which are bonded and cured with the thermosetting resin exuded into the gaps surrounded by the core strand 91 and the side strands 92 , 92 are separated (unstuck) from each other using specific means and process. The bonding between the side strands 92 is also separated (unstuck) from each other. FIG. 8A and FIG. 8B show the process and the device therefor. A strand separating device e includes a rotatable separation plate 70 , and a separation voice 75 and the binding voice 76 are positioned on the downstream side and the upstream side of the separation plate 70 , respectively. The separation plate 70 is formed of a circular metallic plate and includes a core strand insertion hole 73 for insertion of the core strand 91 of the cured composite twisted cable 90 at the center thereof and a plurality of side strand insertion holes 74 arranged radially from the core strand insertion hole 73 apart from each other uniformly. In this example, there are provided the six side strand insertion holes 74 . The separation of the core strand 91 and the side strands 92 are performed as follows. In other words, the cured composite twisted cable 90 wound around the reel 69 is inserted through the separation voice 75 , a terminal end of the inserted cured composite twisted cable 90 is unlaid into individual strands. The core strand 91 is inserted through the core strand insertion hole 73 of the separation plate 70 , and the six side strands 92 are inserted respectively through the side strand insertion holes 74 . Then, the strands 91 and 92 passed through the separation plate 70 are introduced into the binding voice 76 , and are guided to a reel 80 via a capstan 79 . At this time, the separation plate 70 is rotated in the direction opposite from the direction of twisting of the cured composite twisted cable 90 in conjunction with a speed of pulling out the cured composite twisted cable 90 . With this process, the core strand 91 and the side strands 92 of the cured composite twisted cable 90 are separated and the side strands are separated from each other, and hence the bonded state is released. Therefore, the unstuck independent strands are restored to “1×7” twisted relationship in the binding voice 76 , and hence is withdrawn as the fiber composite twisted cable 1 according to the embodiment of the invention in FIG. 1 and is wound around the reel 80 . The fiber composite twisted cable 1 is improved in flexibility because the gaps, which allow the independent behaviors of the respective strands 21 , 22 when the cable is bent, are formed between the core strand 21 and the side strands 22 surrounding the same, which constitute the cable, as shown in FIG. 1 and FIG. 2 , so that the reel 80 may be downsized in diameter of the barrel and the flange in comparison with the reel for winding the cured fiber composite twisted cable 90 in the related art. Therefore, the style of packaging is downsized and the weight is reduced, so that easy transport is achieved. Referring now to the attached drawings, a second embodiment of the invention will be described. FIG. 9A shows a fiber composite twisted cable 100 having a structure of 1×19 including nineteen strands, and having a diameter of 18 mm according to the second embodiment of the invention. The composite twisted cable 100 is configured as described in the first embodiment, and the strands are separated and independent without being bonded to each other so that gaps for allowing independent behaviors of the respective strands when the cable is bent are formed between a core strand and side strands surrounding the same. The composite twisted cable 100 includes a single core strand 111 and six first layer strands 112 twisted so as to surround the core strand 111 , and also includes twelve second layer strands 113 twisted on an outer periphery thereof. The respective strands 111 , 112 and 113 have a configuration including a plurality of twisted prepregs, which are formed of bundles of PAN carbon fiber impregnated with thermosetting resin as in the first embodiment, and outer peripheries of the strands are covered with a fiber yarn 400 wound therearound at an angle close to a right angle with respect to the axial direction of the strand in the high density. Reference numerals 500 designate five substantially triangle shaped gaps surrounded by the core strand 111 and the first layer strands 112 and 112 . By the existence of the gaps, the first layer strands 112 and 112 , and the core strand 111 are separated and independent and are only in contact with each other in the longitudinal direction without being bonded to each other. The adjacent first layer strands 112 and 112 are also separated and independent in the longitudinal direction without being bonded to each other. Reference numerals 501 designate six substantially crescent-shaped gaps surrounded by the first layer strands 112 and the second layer strands 113 , and the first layer strands 112 and the second layer strands 113 are separated and independent and are only in contact with each other in the longitudinal direction without being bonded to each other. The adjacent second layer strands 113 and 113 are also separated and independent and are only in contact with each other in the longitudinal direction without being bonded to each other. The gaps 500 , 501 function as spaces which allow independent behaviors of the strands when the cable is bent in the direction at a right angle with respect to the longitudinal direction of the cable. The manufacturing process will be described, the core strand 111 , the first layer strands 112 , and the second layer strands 113 after having covered with the fiber yarns are twisted into an uncured fiber composite twisted cable in a state in which the thermosetting resin contained therein is not cured, and the thermosetting resin is cured by applying the heat treatment on the uncured fiber composite twisted cable, whereby a semi-finished product as shown in FIG. 9B is obtained. At this time, as in the case of the first embodiment, the core strand 111 and the first layer strands 112 are integrally bonded with the exuded liquid-state thermosetting resin 300 , and the first layer strands 112 and the second layer strands 113 surrounding the same are integrally bonded with the exuded liquid-state thermosetting resin 300 . In order to obtain the above-described composite twisted cable 100 , as in the case of the first embodiment, it is forcedly unstuck using a separating device to release the bonded state. Other points are the same as described in the first embodiment. Referring now to the attached drawings, a third embodiment of the invention will be described. FIG. 10A shows a fiber composite twisted cable 200 having a structure of 1×37 including thirty seven strands, and having a diameter of 28 mm according to a third embodiment of the invention. The cable 200 includes a single core strand 211 and six first layer strands 212 twisted so as to surround the core strand 211 , includes twelve second layer strands 213 twisted on an outer periphery thereof, and further includes eighteen third layer strands 214 twisted on the outer periphery thereof. Reference numerals 500 designate five substantially triangle shaped gaps surrounded by the core strand 211 and the first layer strands 212 and 212 . By the existence of the gaps, the first layer strands 212 and 212 , and the core strand 211 are separated and independent and are only in contact with each other in the longitudinal direction without being bonded to each other. Reference numerals 501 designate six substantially crescent-shaped gaps surrounded by the first layer strands 212 and the second layer strands 213 , and the first layer strands 212 and the second layer strands 213 are separated and independent and are only in contact with each other in the longitudinal direction without being bonded to each other. The adjacent second layer strands 213 and 213 are also separated and independent without being bonded to each other and are in contact with each other in the longitudinal direction. Reference numerals 502 designate a number of diamond-shaped gaps surrounded by the second layer strands 213 and the third layer strands 214 . With these gaps, the second layer strands 213 and the third layer strands 214 are separated and independent and are in contact with each other in the longitudinal direction without being bonded to each other. The adjacent third layer strands 214 and 214 are also separated and independent without being bonded to each other and are in contact with each other in the longitudinal direction. The gaps 500 , 501 and 502 function as spaces which allow independent behaviors of the strands when the cable is bent in the direction at a right angle with respect to the longitudinal direction of the cable. The core strand 211 , the first layer strands 212 , the second layer strands 213 and the third strands 214 after having covered with the fiber yarns are twisted into an uncured fiber composite twisted cable in a state in which the thermosetting resin contained therein is not cured, and the thermosetting resin is cured by applying the heat treatment on the uncured fiber composite twisted cable, whereby a semi-finished product as shown in FIG. 10B is obtained. At this time, as in the case of the first embodiment, the core strand 211 and the first layer strands 212 are integrally bonded with the exuded liquid-state thermosetting resin 300 , and the first layer strands 212 and the second layer strands 213 surrounding the same, and the second layer strands 213 and the third layer strands 214 surrounding the same are integrally bonded with the exuded liquid-state thermosetting resin 300 . In order to obtain the above-described composite twisted cable 200 , as in the first embodiment described above, it is forcedly unstuck using the separating device to release the bonded state of the strands with respect to each other. Other points are the same as described in first embodiment. FIGS. 11A , 11 B and 11 C show examples in which the fiber composite twisted cable according to the embodiment of the invention is used as a reinforcing member for an overhead transmission line. High-voltage transmission lines B extended between steel towers A in FIG. 11A have a structure as shown in FIG. 11B and FIG. 11C . In other words, the fiber composite twisted cable 1 in the first embodiment is used as a core member, and aluminum lines or heat-proof aluminum alloy wires 900 are arranged in two layers and twisted on the periphery thereof. FIGS. 12A and 12B show examples in which the fiber composite twisted cable according to the embodiment of the invention is applied to a reinforcing member of a concrete structure. In order to reinforce a bridge girder C, the fiber composite twisted cables 1 , 100 , or 200 according to any one of the first to the third embodiments are extended between the bridge girders C provided at both ends in the longitudinal direction, and a tonicity is applied thereto using a fixing member. The fiber composite twisted cable according to the embodiments of the invention is applied also to cables for a suspension bridge or ground anchors.
The invention relates to a composite twisted cable formed by impregnating carbon fibers with thermoplastic resin, and provides a fiber composite twisted cable which allows downsizing of a reel by being easy to be bent, can be transported to mountain areas which is normally hard to achieve a transport with a large vehicle, is hard to be curled, and is superior in workability. It is a cable having 1×n structure which is formed by impregnating bundles of carbon fibers with thermosetting resin, then twisting a plurality of strands each formed by covering an outer periphery of the bundle with a fiber, and then curing the thermosetting resin by applying the heat treatment, and a core strand and side strands which constitute the cable are separated and independent without being bonded so as to allow independent behavior of the respective strands when the cable is bent.
3
This is a continuation-in-part of copending application Ser. No. 07/914,671, filed on Jul. 16, 1992, now abandoned. BACKGROUND OF THE INVENTION This invention relates to packing elements for use in chemical process equipment. It relates specifically to random packing elements of a novel and advantageous design useful in mass transfer applications. "Mass transfer" has been defined as the transfer of one or more components from one immiscible phase to another. This "component" may be a chemical or it may be heat. In the case in which the component is heat this may be combustion heat or reaction heat that needs to be removed from a reaction stream before further processing, or from a hot stream of fluid before it can be collected or used. The component can also be a chemical such as a gas component to be removed from a gas stream by absorption, or a component of a liquid mixture to be treated by a distillation or separation process. For such applications and a plurality of other applications involving mass transfer, it is conventional to pass the fluid to be treated through a column containing randomly disposed packing elements. These elements are hereinafter referred to as mass transfer elements for simplicity, regardless of the actual process in connection with which they are actually designed to be used. Clearly the most efficient mass transfer elements are those that present the largest surface area to the fluid for contact. There have therefore been many attempts to design random packing elements with this surface area feature maximized. It is found however in practice that other characteristics are also extremely desirable. For example, it is also valuable if the elements do not nest together when in the column because this reduces the effective surface area exposure. It is also important that the elements do not pack so tightly as to restrict the fluid flow and generate a large pressure drop between the entrance and exit of the column. The balancing of these often competing requirements to produce an effective mass transfer element is a matter of considerable skill and involves compromises to achieve the optimum combination of properties. DESCRIPTION OF THE INVENTION A new design for a random packing mass transfer element has now been discovered that produces a very advantageous balance of desirable properties. The mass transfer element of the invention comprises a generally tubular structure in which the tube wall has been inwardly deformed at opposed ends of mutually perpendicular diameters to provide a cross-section with four external lobes. The inward deformations at opposite ends of each diameter are preferably of uniform amounts such that the convexity of the internal wall surface of each deformation has the same radius of curvature. The inward deformations at opposed ends of the perpendicular diameter are also equal in the radius of curvature of the inside wall surface but, in one preferred embodiment, preferably have a different radius of curvature from those of the depressions at the ends of the other diameter such that the four external lobes give the element cross-section the appearance of a bow-tie. The ratio of the two radii of curvature in this preferred embodiment may vary widely but is preferably from about 1:1 to about 4:1, and most frequently from about 2:1 to about 3:1. In an alternative form the radii of curvature of the two sets of internal convexities are the same but the angle subtended by the extremes of the convexity is greater for one opposed pair than for the other. In practical terms this means that the intrusion of the larger pair of convexities into the internal space of the element is greater than for the others. In an extreme form of this embodiment, the intrusion of the two larger opposed convexities is such that the opposed internal surfaces touch and the axial passage through the element is effectively divided into two. In a second preferred embodiment, the radii of curvature of all inside surfaces of the four deformations are equal and the internal intrusions of all four are the same, so as to form an internal axial passage of essentially cruciform cross-section. The axial length of the element can be any convenient amount but usually this is from about 0.5 cm to about 3 cm and preferably from about 1 cm to about 2 cm. The greatest cross-sectional dimension is usually greater than the axial length and often from about 2 to about 6 times greater. Most frequently the greatest cross-sectional dimension is from about 2 to about 4 times the axial length. The outer surface of the element comprises four convex lobes and these may be separated by concave surfaces corresponding to the convexities on the internal surfaces or by linking surfaces of little or no curvature in either direction. In general this latter type of connecting surface is preferred with elements having four lobes of equal size. Where the lobes are separated by concave surfaces, these concavities may be provided with ribs extending axially along the length of the element. In a preferred construction there are from about 2 to about 6, and more preferably, from 3 to 4 ribs in each concavity and most preferably in only the concavities with the greater radius of curvature. In addition, especially with the "bow-tie" configuration described above, it is often advantageous to provide that an interior strengthening strut be formed between, and along the length of the interior convex surfaces at their point of closest approach. This makes the elements stronger and less likely to fracture if accidentally dropped. The strut is conveniently formed in the same extrusion operation forming the basic shape. While the shape of the elements of the invention has been described as cylindrical, it is anticipated that the cross-sectional shape may vary along the length of the cylinder without departing from the essential concept of the invention. Thus the cylinder may be slightly tapered or be formed with a "waist" with the greatest cross-sectional dimension having a minimum at about the midpoint of the length. It should be recalled however that such departures may increase the pressure drop from one end of the bed to the other and perhaps alter the packing of the elements in the bed. Such deviations are therefore tolerable only to the extent that they do not significantly diminish the effectiveness of the element for its primary purpose. The ends of the element along the axis can be formed with the wall ends shaped to conform to theoretical curved surfaces that are convex or, more preferably, concave. Thus, in preferred embodiments, the ends of the elements are hollowed such that the axial length is less than the length at the periphery. The extent of the hollowing is can be such the axial length along the axis is from about 60% to about 90%, and more usually about 75%, of the axial length at the periphery. The material from which the cylinder is made may be any of those typically used for such purposes. Thus the preferred material is a ceramic or fired clay material though other materials such as a glass or metal could be used in certain applications. Generally the material should be inert to the fluid to which it will be exposed. Where heat transfer uses are involved, it should also be capable of absorbing heat in the amounts required by the process. It should also be capable of withstanding both thermal and physical shock during loading and use. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a first element according to the invention. FIG. 2 shows a perspective view of a second embodiment. FIG. 3 shows a perspective view of a third embodiment. FIG. 4 shows a perspective view of a fourth embodiment. DESCRIPTION OF PREFERRED EMBODIMENTS The invention is now described with reference to the drawings which are for the purpose of illustration only and are intended to imply no essential limitation on the scope of the invention claimed particularly in the matter of dimensions. In FIG. 1 of the Drawings, the cylindrical element has four equal sized external lobes. The internal surface has four equally spaced convexities. The greatest cross-sectional outside diameter of the element is 3.33 cm and the greatest length is 2.54 cm. At each end of the cylinder, the surfaces of the element are shaped to form part of a theoretical concave surface such that the opposed theoretical surfaces are separated by 1.91 cm at their closest approach on the axis of the element. The radius of curvature of the external lobes is 0.64 cm and that of the internal convexities is 0.60 cm. The external lobes are connected by convex surfaces with a radius of curvature of 1.03 cm and the internal lobes are connected by concave surfaces with a radius of curvature of 0.95 cm. FIG. 2 illustrates an embodiment in which the thickness of the wall of the cylindrical element remains essentially constant and in which the internal surface is provided with convexities of different radii of curvature with one opposed pair, at opposite ends of a first diameter, having the same, (greater), convexity and the other opposed pair at the ends of a second diameter at right angles to the first, having a lesser degree of convexity. The outer surfaces of the greater internal convexities are each provided with four equally spaced axially extending ribs. The radii of curvature of the greater of the internal convexities are 2.31 cm and the radii of curvature of the lesser convexities are 1.17 cm. The axial length of the element is 1.42 cm, the wall thickness is 0.28 cm and the greatest separation between the outside surfaces of adjacent lobes is 5.31 cm. FIG. 3 shows a structure similar to that of FIG. 2 but with more pronounced external lobes and with internal convexities that are not quite so different. The structure also lacks the external axial ribs. The two larger opposed internal convexities have radii of curvature of 1.25 cm, (0.89 cm is the radius of curvature of the opposed concave surface), and the smaller have radii of curvature of 0.89 cm, (0.53 cm is the radius of curvature of the opposed concave surface). The wall thickness is 0.36 cm and the axial length is 1.42 cm. The greatest separation between outside surfaces of adjacent lobes is 4.37 cm. FIG. 4 is like the embodiment of FIG. 3 except that the greater internal convexities are so large that they meet at the element axis. In this embodiment the radii of curvature of all the external surfaces corresponding to the internal convexities are 1.91 cm however one opposed pair are so pronounced that the internal surfaces meet. The axial length of the element is 1.91 cm and the wall thickness is 0.95 cm.
Mass transfer elements with an essentially four-lobed cylindrical configuration are particularly effective random dumped packing elements for mass transfer towers, providing a combination of high surface area and low pressure drop.
8
RELATED APPLICATION [0001] This application is co-pending with and includes the same inventor as pending Provisional Application No. 61/229,402 filed on Jul. 29, 2009 and entitled: “Metadata as Comments for Problem Determination;” and the present application is a non-provisional of that Provisional Application and claims priority thereto and incorporates by reference the entirety of that Provisional Application herein. BACKGROUND [0002] One of the major reasons why applications exhibit poor performance is due to runaway queries. If Hibernate or other Object Relation Mapping (ORM) framework is not mapped correctly, it can produce a behavior known as N+1 Select where in a many-to-one relationship the one row in the table generates many (N) unnecessary Select statements. [0003] Thus, improved mechanisms for identifying poor performing queries are needed. SUMMARY [0004] In various embodiments, techniques for using metadata as comments for search problem determination and analysis are presented. According to an embodiment, a method for using metadata with search queries for analysis is provided. Specifically, An action against a search query is detected. Contextual information is gathered for the search query in response to the action. The contextual information is retained as metadata that is carried as comments with the search query when the action is performed on the search query. BRIEF DESCRIPTION OF THE DRAWINGS [0005] FIG. 1 is a diagram of a method for using metadata with search queries for analysis, according to an example embodiment. [0006] FIG. 2 is a diagram of another method for using metadata with search queries for analysis, according to an example embodiment. [0007] FIG. 3 is a diagram of a metadata search query analysis system, according to an example embodiment. DETAILED DESCRIPTION [0008] FIG. 1 is a diagram of another method 100 for using metadata with search queries for analysis, according to an example embodiment. The method 100 (hereinafter “query analysis service”) is implemented as instructions within a computer-readable storage medium that execute on one or more processors, the processors are specifically configured to execute the query analysis service. The query analysis service is operational over a network; the network is wired, wireless, or a combination of wired and wireless. [0009] In an embodiment, the search query language is structured query language (SQL). It is noted that the teachings presented herein are not so limited to any particular query language and others can be used. SQL is presented for purposes of illustration and comprehension and other query languages can be used as well. [0010] At 110 , the query analysis service detects an action against a search query. Actions can include a variety of processing, such as a save operation and query execute operation, and the like. [0011] According to an embodiment, at 111 , the query analysis service identifies the action as a save operation that a user initiates to save the search query within a query interface tool. [0012] In another case, at 112 , the query analysis service identifies the action as an execute query operation initiated to execute the query against a database. [0013] It is also noted that the actor performing the action does not have to be a user. That is, some actors can be automated applications that other indirect actions performed by a user can cause to be initiated. So, the action may be associated with an automated actor. [0014] At 120 , the query analysis service gathers contextual information for the query in response to the action. Contextual information can include a variety of types of information that is automatically gathered by the query analysis service. [0015] For example, at 121 , the query analysis service identifies the contextual information as one or more of the following: a server identifier for a service where the action was initiated (such as query interface tool, customer relationship manager (CRM) tool, and the like); a user identifier for a user that is performing the action (this can be an actor identifier for automated actors as discussed above); an action identifier for identifying the action being taken (save, execute, and the like); and/or date and time information for when the action was taken. [0016] In another case, at 122 , the query analysis service inspects environmental variables within a processing environment where the actions are taken on the processor to gather at least some of the contextual information. That is, environmental settings for the processing environment can be interrogated by the query analysis service to gather some of the contextual information. [0017] In yet another situation, at 123 , the query analysis service identifies a session identifier having the user identifier for a user as part of the contextual information when the action is taken. So, a communication session established between the user and a search tool can be interrogated to acquire details about the session and used as part of the automated contextual information obtained by the query analysis service. [0018] At 130 , the query analysis service retains the contextual information as metadata that is then carried as comments within the search query when the action is subsequently performed on the query. That is, the metadata (contextual information) is appended to the search query as a comment that the query language ignores and carries with the search query. [0019] So, according to an embodiment, at 131 , the query analysis service appends a comment syntax recognized by the query language of the search query at the end of the search query. Following the comment syntax, the query analysis service appends the metadata to ensure that the subsequent action taken on the search query retains the comments but does not interfere with processing the action in a normal manner. [0020] In another situation, at 132 , the query analysis service appends the comments within memory having the query to ensure that when the action is taken the comments are present with the query. An example of doing this is provided below within the context of a JAVA® Thread Object. Here, should the query be submitted as an execute operation, the comment can be appending in memory with that call to ensure the comment is present when the query is executed. [0021] At 140 , the query analysis service logs the search query and the comment in a log database for subsequent database mining and analysis. That is, the comment and other previous comments can be indexed and stored in multiple database tables and subsequently evaluated via normal database mining operations to identify problems with particular queries, problems with queries particular users execute, and the like. [0022] FIG. 2 is a diagram of another method 200 for using metadata with search queries for analysis, according to an example embodiment. The method 200 (hereinafter “metadata service”) is implemented as instruction within a computer-readable storage medium that execute on a plurality of processors, the processors specifically configured to execute the metadata service. The metadata service is operational over a network; the network is wired, wireless, or a combination of wired and wireless. [0023] The metadata service represents processing occurring when a search query having an existing comment is executed. The processing discussed above with respect to the method 100 of the FIG. 1 represents processing that occurs when the comments are initially gathered and carried with a search query. [0024] At 210 , the metadata service retains comments that are embedded within a query. So, comment syntax that can be carried in a query language with a query and that are typically ignored by the service executing a query are detected and stripped and retained by the metadata service. [0025] According to an embodiment, at 211 , the metadata service parses the query for comment syntax and copies out the comments following the comment syntax from the query. This is a mechanism for initially recognizing the presence of the comments and retaining them. [0026] In yet another scenario, at 212 , the metadata service augments the original comments with additional contextual information present in a processing environment where the query is being executed. Here, where the comments were originally carried with the query may be an entirely different environment from where the query is actually executed. So, the metadata service can gather additional details that may be relevant to the processing environment of where the query is being executed, such as processor load of the processor, other services processing, and the like. [0027] At 220 , the metadata service logs the comments (and any additional dynamically gathered contextual information at run time of the query) for subsequent analysis and data mining. [0028] In an embodiment, at 221 , the metadata service indexes the comments into a database table based on user identification or user action. So, the relevant information in the comments are capable of being mined and analyzed in view of a particular user or a particular action being taken on the query. [0029] In a related situation, at 222 , the metadata service stores the comments into multiple database tables based on identifiers parsed from the comments. This permits multiple associations or relationships to be associated with the query and the comments. The identifiers can include a variety of information, such as but not limited to, a user identifier, a source tool identifier where the query was initiated, an action identifier for an action taken on the query, a database table identifier for a database table being searched using the query, and/or a query identifier that uniquely identifies the query. [0030] In an embodiment, at 240 , the metadata service returns results to a requesting user of the query after the query is executed and provides a link with the query results that identifies for the user the comments that were logged. So, the users can see the metadata captured as comments. [0031] FIG. 3 is a diagram of a metadata search query analysis system 300 , according to an example embodiment. The metadata search query analysis system 300 is implemented within and resides within a computer-readable storage medium and executes on one or more processors specifically configured to execute the components of the metadata search query analysis system 300 . Moreover, the metadata search query analysis system 300 is operational over a network and the network is wired, wireless, or a combination of wired and wireless. [0032] The metadata search query analysis system 300 implements, inter alia, the method 100 of the FIG. 1 and the method 200 of the FIG. 2 . [0033] The metadata search query analysis system 300 includes a comment gathering service 301 and a comment logger service 302 . Each of these and their interactions with one another will now be discussed in turn. [0034] The comment gathering service 301 is implemented in a computer-readable storage medium and executes on a processor. Example aspects of the comment gathering service 301 were provided in detail above with reference to the method 100 of the FIG. 1 . [0035] The comment gathering service 301 is configured to collect contextual information when an action is initiated on a search query and configured to add the contextual information as metadata represented via comments of the search query. [0036] In an embodiment, the comment gathering service 301 is also configured to identify types of contextual information to collect based on policy that is dynamically evaluated and used to configure the comment gathering service 301 for initial processing. [0037] In yet another case, the comment gathering service 301 is configured to pass the search query to a search query processor to perform user-directed actions on the search query once the metadata is acquired and integrated as the comments into the search query. [0038] The comment logger service 302 is implemented in a computer-readable storage medium and executes on a processor. Example aspects of the comment logger service 302 were provided above in detail with reference to the methods 100 and 200 of the FIGS. 1 and 2 , respectively. [0039] The comment logger service 302 is configured to strip the comments from the search query when the search query is executed against a database and log the comments for subsequent analysis. [0040] According to an embodiment, the comment logger service 302 is configured to store the comments in multiple database tables based on information parsed from the comments. [0041] In another situation, the comment logger service 302 is configured to gather additional contextual information to augment the comments. The additional contextual information also logged with the comments. This scenario was discussed above with reference to the method 200 of the FIG. 2 . [0042] Some sample scenarios and illustrations are now presented for further comprehension of the invention. These are not intended to limit the teachings presented herein to any particular implementation or scenario. [0043] SQL comments are made use of to add query metadata that accompanies the query, for example: [0044] select*from Orders-- userId:Ray [0000] Raichura,time:1225205869734,dispatch:editObjectFromFinder,ver:06.00.02. 03,url: trm/finderChooseExisting.do,thread:http-sor25; [0045] All characters after the “--” comment marker are ignored but retained by the SQL parser. The full SQL statement is sent to the database for execution and is also logged by a Database Query Logger or Log Script (DBQL). [0046] A DBQL provides a series of predefined tables that can store historical records of queries and their duration, performance, and target activity. DBQL caches and eventually stores query information in multiple Data Dictionary tables as the queries are executed. [0047] Consider a few entries for Queries with comments in a DBQL as follows: [0048] 1) Select t, “Update_DTTM”,t,“MESSAGE_ID”,t,“Update_USER” from ex-message as t where MESSAGE_ID=‘TMSGA0000050’—url:/trm/communication.do,ver:6.0,3.0,83349.branches/stable/dispatch:ajaxSubmitEntity,usi d:jack [0049] 2) Select t, “Update_DTTM”,t,“STEP ID”,t,“Update_USER” from ex-step as t where STEP ID=‘BBBBWNWNBBBX’—url:/trm/communication.do,ver:6.0,3.0,83349.branches/stable/dispatch:ajaxSubmitEntity,use rid:perf [0050] The metadata information is captured at the very beginning of a user action i.e. Clicking Save. The information is stored in Java's ThreadLocal object which allows transportation of data within the same thread. At the end of the user action and right before the query is sent to the database for execution, the data stored in ThreadLocal object is retrieved and appended to the query as comments. [0051] One way to figure out the submitter of a query is by looking at Username column in DQBL. This lists the name of the logged-in user under whom the query was issued. Unfortunately this is not always accurate as Connection Pooling defeats it. Connection Pooling opens up multiple connections to the database (at application start-up) under one generic user. So DBQL will show that all queries were issued by this one generic user. [0052] The solution allows one to map each query to a user and their activities. Without the appended metadata as comments, there is no way to accurately determine the origination of a query. In addition, macros group the data by user, screen, and action. From these macros, one is able to figure out: [0053] How many queries were issued by the user during a certain time period. [0054] How many queries were issued by a certain action such as clicking Save. [0055] Number of queries issued by screen showing usage pattern. [0056] The above description is illustrative, and not restrictive. Many other embodiments will be apparent to those of skill in the art upon reviewing the above description. The scope of embodiments should therefore be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled.
Techniques for using metadata as comments to assist with search problem determination and analysis are provided. Before an action is taken on a search, contextual information is gathered as metadata about the action and actor requesting the action. The metadata is embedded in the search as comments and the comments are subsequently logged when the action is performed on the search. The comments combine with other comments previously recorded to permit subsequent analysis on searches.
6
CROSS REFERENCE TO RELATED APPLICATIONS The present invention is a divisional of, claims priority from, and incorporates by reference the entirety of U.S. patent application Ser. No. 09/347,360, which was filed on Jul. 6, 1999 now U.S. Pat. No. 6,602,369. BACKGROUND OF THE INVENTION The present invention relates to a process for producing a laminated sheet comprising an alumina fiber precursor spun out from a spinning solution containing an aluminum compound. More particularly, it relates to a process for producing a laminated sheet comprising an alumina fiber precursor having a uniform basis weight throughout. Alumina fiber sheet obtained by calcining the said laminated sheet has excellent refractory and heat insulating properties as well as high mechanical strength and chemical stability even under high temperatures and are used as a high-temperature refractory/heat insulator, high-temperature cushioning medium and such. It is known to produce alumina fiber by first forming an alumina fiber precursor by spinning from a spinning solution, and then calcining the said precursor. This method is especially suited for producing alumina fiber whose alumina content exceeds 65% by weight, such the production that the conventional melt fiber-forming method is inapplicable. The spinning solution used in this method is principally comprising an aluminum compound and contains small amounts of various adjuvants. The adjuvants include those which become the structural elements of the finally produced alumina fiber, such as metal compounds, and those which serve for adjusting the properties of the spinning solution, such as water-soluble polymeric compounds. For example, a spinning solution prepared by adding silica sol and polyvinyl alcohol to a basic aluminum chloride solution formed by dissolving aluminum in hydrochloric acid is used. Blowing method and spindle method utilizing centrifugal force are known for spinning out an alumina fiber precursor from a spinning solution, but usually blowing method is used. According to this blowing method, the spinning solution is supplied into a high-speed spinning air stream from a nozzle, the-supplied spinning solution being drawn out in the spinning air stream, deprived of moisture and solidified to form an alumina fiber precursor. The thus formed alumina fiber precursor is amassed to form an alumina fiber precursor sheet having a specified basis weight, i.e., a specified weight per unit area. Although the constituent alumina fiber precursor has flexibility, the precursor sheet itself is low in fiber strength and also unstable as it contains structural water and/or additives in fiber, so that usually this precursor sheet, can not be offered as a commercial product in the form as it is. Therefore, it is necessary to calcine the alumina fiber precursor sheet to form an alumina fiber sheet having high crystallinity while maintaining a stable oxide state. It is also possible to obtain an alumina fiber sheet with even higher mechanical strength by needling the precursor sheet before calcining. (See U.S. Pat. Nos. 4,752,515, 4,931,239 and 5,104,713). As means for producing an alumina fiber precursor sheet having a specified basis weight (fiber weight per unit area or basis area weight) by amassing the alumina fiber precursor, a method is known in which the alumina fiber precursor in the spinning air stream is fallen and stacked on an accumulator until a sheet with a specified basis weight is formed. For example, the alumina fiber precursor is fallen and stacked on a rotating endless belt, and the alumina fiber precursor sheet formed by stacking the said precursor is successively tugged out from the endless belt. A method is also known in which the alumina fiber precursor carried in the spinning air stream is fallen and stacked on an accumulator to form a thin lamina sheet which is far smaller in thickness than the sheet to be formed having a specified basis weight, and this lamina sheet, in the next step, is wound round a number of times until forming the sheet with a specified basis weight. In a typical example of this method, a spinning air stream containing the alumina fiber precursor is let impinge almost at right angles against a rotating endless belt of the type which allows easy passage of air, such as a belt made of (metal) wire mesh (net). The spinning air stream is allowed to pass through the endless belt, but the alumina fiber precursor is caught and amassed on the endless belt to form a lamina sheet. This lamina sheet of alumina fiber precursor is pulled apart from the endless belt and wound around a rotator in whatever layers until forming a sheet having a specified basis weight. Then the roll of the laminated sheet on the rotator is cut into sections, and subjected to the ensuing steps such as calcining. According to the above method, although capture and amassing of the alumina fiber precursor from the spinning air stream is easy, the sheet forming operations are complicated as they are batch type, and further, since the length of the sheet that can be treated depends on the circumferential length of the rotator, it is impossible to obtain sheets of all required lengths. A further problem of the said conventional method is that the formed alumina fiber precursor sheet is non-uniform in basis weight along the width thereof, the basis weight being particularly small at both end portions of the sheet. This is for the reason that when the alumina fiber precursor is fallen from the spinning air stream and stacked on an accumulator, the precursor does not stack uniformly along the whole width of the accumulator, and most remarkably the stacking at both ends in the width direction is relatively small. That the basis weight of the alumina fiber precursor sheet is non-uniform along the width thereof, particularly small at both ends, signifies corresponding variation of the basis weight of the calcined alumina fiber sheet in its width direction. An alumina fiber sheet as a commercial product is required to be uniform in basis weight in its entirety, so that both end portions in the width direction where the basis weight is smaller than the specified value must be cut out rather overly, which results in a reduced yield of the alumina fiber sheet. Also, even if both end portions are cut out, the sheet would have to be disposed off as a substandard product if there still exists a portion where the basis weight is outside the specified range. In recent years, attention is focused on application of alumina fiber sheets to such areas as holding means for exhaust gas cleaning systems, heat-resistant filters and the like, and in such uses, higher precision of sheet thickness than in the conventional uses is required. For example, in the internal combustion engines, as a measure for disposal of exhaust gas, a cleaning system having a honeycomb catalyst housed in a casing is provided in the exhaust gas passage. For securely holding such honeycomb catalyst in the catalyst casing, it is necessary to wind a holding mat for catalyst holding member around the honeycomb catalyst to as much a uniform thickness as possible and house this catalyst in the casing so that it will be closely secured to the inside wall of the casing by the restoring force of the holding member. Such a holding member is preferably a fiber sheet which is proof against fiber deterioration and capable of maintaining an appropriate surface pressure even under high temperatures. Japanese Patent Application Laid-Open (KOKAI) No. 7-286514, for instance, teaches that among alumina fiber sheets, the one produced by laminating alumina fiber having a composition of Al 2 O 3 :SiO 2 =70-74:30-26 (by weight) and needling the laminate is especially preferred. As a result of the present inventors' earnest studies to solve the above problem, it has been found that by folding the thin lamina sheet of alumina fiber precursor by a predetermined width while stacking the folded sheet and continuously moving the stacking sheet in the direction orthogonal to the folding direction, the obtained alumina fiber precursor sheet has uniform basis weight along the full width thereof. The present invention has been attained on the basis of the above finding. SUMMARY OF THE INVENTION An object of the present invention is to provide a process for producing an alumina fiber precursor sheet which is uniform in basis weight along the full width thereof. To attain the above aim, in the first aspect of the present invention, there is provided a process for producing a laminated sheet comprising an alumina fiber precursor, which process comprises spinning out an alumina fiber precursor from a solution mainly comprising an aluminum compound, falling and stacking said alumina fiber precursor on the surface of an accumulator to form a thin lamina sheet of alumina fiber precursor, continuously pulling out said lamina sheet from the accumulator, transferring the resultant lamina sheet to a folding device, and folding the sheet by a predetermined width while stacking the folded sheet and continuously moving the stacking sheet in the direction orthogonal to the folding direction. In the second aspect of the present invention, there is provided a process for producing an alumina fiber sheet which comprises calcining a laminated sheet of alumina fiber precursor obtained from a process according to the first aspect. In the third aspect of the present invention, there is provided a holding mat for catalyst holding member, which comprises an alumina fiber sheet produced by needling and calcining a laminated sheet of alumina fiber precursor obtained from a process comprising spinning out an alumina fiber precursor from a solution mainly comprising an aluminum compound, falling and stacking said alumina fiber precursor on the surface of an accumulator to form a thin lamina sheet of alumina fiber precursor, continuously pulling out said lamina sheet from the accumulator, transferring the resultant lamina sheet to a folding device, and folding the sheet by a predetermined width while stacking the folded sheet and continuously moving the stacking sheet in the direction orthogonal to the folding direction. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic flow sheet illustrating an embodiment of the present invention. FIG. 2 is a schematic illustration of a folder system usable in carrying out the present invention. DETAILED DESCRIPTION OF THE INVENTION The present invention is described in detail below. In the present invention, preparation of the spinning solution and formation of the alumina fiber precursor can be accomplished according to the conventional methods. For example, the spinning solution can be prepared by forming a basic aluminum chloride solution by dissolving aluminum in hydrochloric acid, and adding silica sol to the solution so that the finally obtained alumina fiber will have a composition of Al 2 O 3 :SiO 2 =preferably 65˜98:35˜2, more preferably 70˜97:35˜3 (by weight). When the silicon content increases excessively, although it becomes easy to form fibers, heat resistance lowers excessively, while a too small silicon content make the fibers fragile. In order to improve spinnable properties, it is preferable to add a water-soluble organic polymer such as polyvinyl alcohol, polyethylene glycol, starch, cellulose derivatives or the like. In some cases, the solution is properly concentrated to adjust the viscosity usually to 10 to 100 poise. Blowing method, in which the spinning solution is supplied into a high-speed spinning air stream, is preferably used for forming alumina fiber precursor from the spinning solution. The nozzles usable in the blowing method include two types: in one type, a spinning solution nozzle is provided in an air stream nozzle which generates a spinning air stream; in the other type, a spinning solution nozzle is provided so as to supply the spinning solution externally to the spinning air stream. Both types can be used in the present invention. In case where spinning is carried out according to the said blowing method, preferably an endless belt made of metal gauze is set substantially at right angles against the spinning air stream, and the spinning air stream containing the formed alumina fiber precursor is let impinge against the rotating belt. The alumina fiber precursor formed by the said spinning is usually about several micrometers (μm) in diameter and several ten to several hundred mm in length. The thin lamina sheet of alumina fiber precursor formed on the accumulator is successively pulled out from the accumulator and transferred to a folder by which the sheet is folded to a predetermined width and amassed, and the amassed sheet is continuously moved in the direction orthogonal to the folding direction. In other words, the lamina sheet is successively pulled apart from the accumulator, folded and stacked in the advancing direction of the sheet, and continuously moved transversely to the folding direction. Therefore, the folded sheet width becomes equal to the width of the laminated sheet to be formed. Thereby both end portions in the width direction of the lamina sheet are dispersed in the formed laminated sheet, so that the basis weight of the laminated sheet becomes uniform throughout the sheet. The basis weight of the lamina sheet should at least be enough to form a thinnest allowable sheet; it is usually 10 to 200 g/m 2 , preferably 30 to 100 g/m 2 . This thin lamina sheet is not necessarily uniform in both of its crosswise and longitudinal directions, so that the laminated sheet is formed by laminating the lamina sheet in at least 5 layers, preferably 8 or more layers, more preferably 10 to 80 layers. By this lamination, local non-uniformity of the lamina sheet is countervailed, so that it is possible to obtain a laminated sheet having a uniform basis weight throughout. The number of laminations is not specifically limited, but it is to be noted that a too large thickness of the sheet may make it unable to obtain preferred improvement of peel strength in the thickness direction by needling normally conducted in a later step, or may cause a reduction of sheet productivity. For forming the laminated sheet, the lamina sheet is delivered out continuously from the accumulator and transferred to a folder whereby the sheet is folded to a predetermined width, stacked and continuously moved in the direction orthogonal to the folding direction. For example, in the accumulator, alumina fiber precursor is stacked on a metal gauze-like rotating endless belt to form a thin lamina sheet, and this sheet is separated from the endless belt and forwarded to the folder. In this folder, the sheet is folded to a predetermined width and piled up on an endless belt rotating in the direction substantially orthogonal to the folding direction. The number of laminations of the laminated sheet depends on the moving speed of the endless belt. Slow speed increases the number of laminations, while fast speed decreases the number of laminations. FIG. 1 is a schematic flow sheet illustrating an embodiment of the present invention. In this embodiment, there is used a folding system 3 comprising an endless belt 1 for carrying the lamina sheet 2 , another endless belt 5 for carrying the laminated sheet, said endless belt 5 being disposed at a position lower than the endless belt 1 and in the direction transverse thereto, and a folding means by which the lamina sheet hanging from the rear end of the endless belt 1 is folded and stacked on the endless belt 5 . In this folding system 3 , the folding means is arranged movable laterally, and the width of the laminated sheet is decided by the range of travel of the folding means. Use of such folding system makes it possible to continuously produce a laminated sheet 4 of any optional width from the continuously transferred thin lamina sheet. The folding system usable in the present invention is not limited to the structure illustrated in FIG. 1 ; it is possible to use a vertical folding system such as illustrated in FIG. 2 . The thus produced laminated sheet of alumina fiber precursor is then calcined by a conventional method and thereby made into an alumina fiber sheet. Calcining is carried out usually at a temperature not lower than 500° C., preferably 1,000 to 1,300° C. When the laminated sheet is subjected to needling before calcining, it is possible to obtain an alumina fiber sheet with high mechanical strength in which the alumina fibers are also oriented in the thickness direction. Needling is conducted usually at a rate of 1 to 50 stitches/cm 2 . Generally, the higher the needling rate is, the higher become the bulk density and peel strength of the obtained alumina fiber sheet. According to the present invention, it is possible to produce a laminated sheet of alumina fiber precursor having a uniform basis weight throughout. By calcining this laminated sheet by a conventional method after needling, if necessary, there can be obtained an alumina fiber sheet having a uniform basis weight throughout. Further, the present invention enables continuous production of alumina fiber sheet of any optional length with ease and can remarkably improve production efficiency over the conventional methods. EXAMPLES The present invention is described in further detail by showing the examples thereof, which examples however are merely intended to be illustrative and not to be construed as limiting the scope of the invention. Example 1 To an aqueous solution of basic aluminum chloride (aluminum content: 70 g/1, Al/Cl=1.8 (atomic ratio)) was added silica sol so that the finally obtained alumina fibers would have a composition of Al 2 O 3 :SiO 2 =72:28 (by weight). After further adding polyvinyl alcohol, the mixed solution was concentrated to prepare a spinning solution having a viscosity of 40 poises and an alumina/silica content of about 30% by weight, and spinning thereof was carried out with this spinning solution according to the blowing method. A spinning air stream carrying the thus formed alumina fiber precursor was let impinge against a metal gauze-made endless belt, thereby capturing and amassing the alumina fiber precursor to obtain a 1,050 mm wide thin sheet thereof with a basis weight of 40 g/m 2 , which was relatively non-uniform and had the alumina fiber precursor arranged randomly in the plane. This thin sheet of alumina fiber precursor was folded and stacked using a folding device of a structure shown in FIG. 1 to produce a continuous 950 mm wide laminated sheet of alumina fiber precursor comprising 63 layers of folded lamina sheet. This laminated sheet was calcined by first placing it under 300° C. for 2 hours, then successively raising the temperature to 300˜550° C. at a rate of 2° C./min and then to 550˜1,250° C. at a rate of 5° C./min, and finally leaving it under 1,250° C. for 30 minutes to make a continuous alumina fiber sheet measuring about 25 mm in thickness and about 650 mm in width. This alumina fiber sheet was cut to a width of 600 mm and both end portions comprising the turnups were removed. A 2,000 mm portion of this alumina fiber sheet was divided into 6 equal sections in the width direction and into 20 equal sections in the longitudinal direction, and the basis weight of each section was measured. The mean value of basis weight in the width direction of the longitudinally eicosasected sections and the tripled value (3σ/mean value of basis weight×100; %) of its standard deviation were determined. The scatter determined by averaging the determinations in the longitudinal direction (n=20) was 7.7%. Comparative Example 1 A thin lamina sheet obtained according to the same procedure as in Example 1 was wound around a round rotator to produce a 1,050 mm wide laminated sheet of alumina fiber precursor comprising 63 layers of the lamina sheet, and this laminated sheet was calcined to obtain an approximately 40 mm thick and approximately 740 mm width alumina fiber sheet. This alumina fiber sheet was cut to a width of 600 mm and subjected to the same test as said above. The scatter determined in the same way as in Example 1 was 17.4%. Example 2 A thin lamina sheet with a basis weight of 40 g/m 2 and a width of 1,050 mm obtained in the same way as in Example 1 was folded, stacked and separated at a higher rate than in Example 1 to produce a 950 mm wide continuous laminated sheet of alumina fiber precursor comprising 30 layers of the lamina sheet. To this laminated sheet was sprayed 30 ml/kg of a 10 wt % higher fatty acid ester/mineral oil solution as a lubricant, after which the sheet was subjected to needling at a rate of 5 stitches/cm 2 and then calcined in the same way as in Example 1 to make a continuous alumina fiber sheet having a thickness of about 10 mm and a width of 650 mm. Evaluations of this alumina fiber sheet by the same method as used in Example 1 showed a scatter of 6.7%. In order to evaluate suitability of the obtained alumina fiber sheet for use as a holder for exhaust gas cleaning systems, five 50 mm×50 mm square test pieces were collected from the sheet by cutting it in the width direction at equal intervals, and each test piece was subjected to 5-time repetition of a compression/release operation which comprised compressing the test piece to a thickness of 4 mm at room temperature by a compression tester, measuring the surface pressure and then releasing the compression. Each test piece was also subjected to 5-time repetition of a compression/release operation which comprised compressing the test piece to a thickness of 3 mm, measuring the surface pressure and releasing the compression. The results of the above evaluation tests are shown in Table 1. Comparative Example 2 A thin lamina sheet obtained in the same way as in Comparative Example 1 was wound around a round rotator to produce a 1,050 mm wide laminated sheet of alumina fiber precursor comprising 30 layers of the said lamina sheet, and this laminated sheet was needled and calcined as in Example 1 to obtain an alumina fiber sheet having a thickness of about 10 mm and a width of about 740 mm. The scatter of this alumina fiber sheet as determined in the same way as described above was 16.8%. Suitability of the obtained alumina fiber sheet for use as a holder for exhaust gas cleaning systems was evaluated in the same way as in Example 2, the results are shown in Table 1. Comparing Example 2 and Comparative Example 2, both are high in surface pressure, which is little reduced even if thickness alteration is repeated, and both are also high in restorative force of fibers and suited for use as a holder. However, it is remarkable that Example 2 is small in scatter of surface pressure properties between the sheets than Comparative Example 2, and particularly suited for use as a holder material. TABLE 1 Example 2 Comp. Example 2 Compression thickness 4 mm 3 mm 4 mm 3 mm Surface pressure (after 1st/5th application of compression, kg/cm 2 ) Test piece 1 1.5/1.3 3.9/3.8 1.0/1.0 2.8/2.8 Test piece 2 1.4/1.3 3.7/3.7 1.6/1.5 3.9/3.8 Test piece 3 1.6/1.5 4.0/3.9 1.1/1.0 2.9/2.8 Test piece 4 1.5/1.4 3.8/3.7 1.7/1.5 4.3/4.1 Test piece 5 1.6/1.5 4.1/4.0 2.5/2.1 5.2/4.7
The present invention relates to a process for producing a laminated sheet comprising an alumina fiber precursor, which process comprises spinning out an alumina fiber precursor from a solution mainly comprising an aluminum compound, falling and stacking said alumina fiber precursor on the surface of an accumulator to form a thin lamina sheet of alumina fiber precursor, continuously pulling out said lamina sheet from the accumulator, transferring the resultant lamina sheet to a folding device, and folding the sheet by a predetermined width while stacking the folded sheet and continuously moving the stacking sheet in the direction orthogonal to the folding direction.
3
BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a manually operated pencil sharpener and particularly to a mechanical pencil sharpener having a slidably rotatable cutter assembly which is activated by the manual force associated with the insertion of a pencil therein. 2. Description of the Prior Art Manually operated pencil sharpeners are well known. For example, there are the simple blade types or those where a cutter assembly is rotated via gearing, a crank or handle. In order to sharpen a pencil in these types of devices, the operator must hold the pencil in one hand and crank the handle of the pencil sharpener with the other hand or the operator manually rotates the pencil (or sharpener) about its longitudinal axis within a cutter assembly. In general, these types of sharpeners must by clamped, bolted or otherwise affixed to a stable substrate (making them a permanent, non-portable fixture). Other types of manually operated pencil sharpeners having rotatable cutting assemblies are shown in U.S. Pat. Nos. 1,182,327 and 2,470,387. For example, U.S. Pat. No. 1,182,327 teaches a pencil sharpener having two symmetrical knife carrying frames with helically bent cutting blades mounted to a spirally threaded stem. A thumb-nut is threaded on the stem which, when forced down the stem by the action of fingers, forcibly rotates the stem and the cutting frames of the pencil sharpener. Motor-driven sharpeners with separate starting switches are also well known. These motor-driven pencil sharpeners operate on live current or are battery powered. However, they require costly electrical energy and have unattractive cords which are potentially hazardous. The cordless type, such as battery-powered sharpeners, have the disadvantage of requiring frequent changes of batteries. SUMMARY OF THE INVENTION 1. Purposes of the Invention It is an object of this invention to provide a manually operated pencil sharpener having both the convenience of operation associated with an electric pencil sharpener and the economy of a mechanically driven pencil sharpener. Another object of this invention is to provide a manually operated pencil sharpener which is portable, i.e., it need not be fixedly secured or anchored to the surface of a substrate in order to operate it. Still another object of the invention is to provide a pencil sharpener which combines simplicity of construction with efficiency in operation. It is also an object of this invention to provide a pencil sharpener which, because of its simple and elegant design, can be incorporated into a variety of housings therefor. An object of this invention is to provide a pencil sharpener which utilizes the natural insertion motion of a pencil into a cutting assembly to cause rotation of the cutting assembly. A further object of this invention is to provide a pencil sharpener which sharpens a pencil upon insertion of the pencil within the cutting assembly without further manipulation or cranking of a handle. A still further object of this invention is to provide a pencil sharpener which has one or more clutches or coupling assemblies in combination with biasing means such as a spring for sharpening a pencil only when the pencil is inserted into or withdrawn from the cutter assembly. An object of this invention is to provide a pencil sharpener wherein sharpening of a pencil is a one-hand operation. Another object of this invention is to provide a pencil sharpener having a cutter assembly wherein a plurality of insertions and withdrawals of a pencil into and out of the cutting assembly repositions the pencil inside the cutting assembly a sufficient number of times to effect a substantially equal distribution of cutting forces on the pointed end of the pencil. Another object of this invention is to provide a pencil sharpener whereby a pencil is sharpened while the pencil remains inside the cutter assembly during the insertion and withdrawal strokes of the pencil into and out of the cutter assembly. A still further object of this invention is to provide for a cleaner or finished pencil point by removing the remaining loose pencil shavings with light strokes of the cutter assembly. These and other objects and advantages of the present invention will become evident from the description which follows. 2. Brief Description of the Invention This invention relates to a mechanical pencil sharpener which is actuated by the manual force associated with the insertion of a pencil thereinto. Fundamentally, a pencil is inserted into a cutter assembly having a longitudinal axis and which is rotatably and slidably mounted within the pencil sharpener. As the pencil is pushed into the cutter assembly along its longitudinal axis, the cutter assembly axially moves in the direction of insertion. A conversion means is provided for converting the axial movement of the cutter assembly into rotational movement thereof. A coupling means is provided for selectively actuating the converting means when the pencil is inserted into the cutter assembly or withdrawn therefrom, or both. A spring means is employed to automatically return the cutter assembly to its initial position when the pencil is withdrawn therefrom. The rotational movement of the cutter assembly relative to the rotational stationary pencil (held by fingers) operates to sharpen the forward end of the pencil inserted into the cutter assembly. A pencil may be sharpened in the pencil sharpener of this invention by employing one continuous axial insertion stroke with sufficient penetration into the pencil sharpener to sharpen the pencil, or the axial strokes of a pencil in a reciprocating manner (in and out of the sharpener) may be repeated until the pencil is sharpened. Moreover, actual sharpening of the pencil may occur selectively according to the particular coupling assembly employed as discussed more fully subsequently herein. Actual sharpening may thus occur only in one direction of axial movement of a pencil within the sharpener or in both directions (in and out) of such axial movement. The repetitious or reciprocating motion of a pencil being inserted and withdrawn from the cutter assembly provides an opportunity to inspect the degree to which the pencil has been sharpened. Moreover, the slight repositioning of the pencil in the cutter assembly of the pencil sharpener allows for a more perfectly conical point and a more compact pencil sharpener. Various mechanical converting means and coupling assemblies are disclosed in combination with a spring, cutter assembly, rod and other elements according to the present invention. In its broadest aspect, this invention relates to a mechanical pencil sharpener actuated by insertion of a pencil thereinto which sharpener comprises: a frame, a cutter assembly, a rod, a conversion means, a spring and a coupling means. The frame or housing of the pencil sharpener of applicant's invention can assume any number of shapes, such as rectangular, cylindrical, octagonal, prismatic, or even familiar decorative items such as vases, statutes or the like with very little modification. The frame or housing also includes a hollow compartment or chamber for receiving pencil shavings. Generally, the housing has a base which is substantially linear which allows it to be placed upon a table, desk or the like. Also, the surface of the base should hold the housing stationary when used. Consequently, it may be of a material which adheres by friction forces or have means for adhering to a surface on which it is placed, e.g., small rubber pads mounted to the base. The cutter assembly has a longitudinal axis and is rotatably and slidably mounted within the frame. A pencil inserted into the cutter assembly is forced against a portion thereof to cause slidable movement of the cutter assembly in the direction of movement of the pencil, from an initial position to a displaced position. A rod which may contain a helical groove on its external surface or which may be hollow and contain a helical groove on its internal surface or which contains no grooves therein rotates the cutter assembly to sharpen the pencil. The rod has an elongated longitudinal axis, depends from the cutter assembly and is coaxially aligned therewith. Also, the cutter assembly and rod are kinematically unitary, i.e., the rod is fixed to the cutter assembly for slidable movement and rotation in unison therewith. A motion alignment means such as inner and outer telescoping sleeves encasing the cutter assembly and rod is preferably rotatably attached to the cutter assembly and rod for aligning their slidable movement so that such slidable movement is substantially rectilinear. Although the cutter assembly and rod would operate satisfactorily without a motion alignment means, the motion alignment means provides for a more efficient and precise mechanical movement. Another function of the telescopic sleeves 32 and 34 is to act as a dust cover to protect the mechanical parts of the motion converting means and spring. Protective sleeve 34 also provides for a rotatably stationary reference base for those cutter assemblies that require it, i.e., planetary geared cutter assemblies where the geared cutter cylinders rotate and revolve within a rotatably stationary outer gear. This can be accomplished on sleeves 32 and 34 by a longitudinal slidably grooved configuration that would allow the sleeves 32 and 34 to move longitudinally but prevent them from rotating relative to each other. In such an arrangement, sleeve 32 would always be rotatably and slidably stationary. A conversion means, for example, a cylindrical, helical-groove, engaging sleeve (when a helical groove containing rod is used) rotatably mounted within the frame and meshing with the helical groove of the rod, translates the sliding rectilinear movement of the rod and cutter assembly into simultaneous rotational movement thereof. When a helical-groove containing rod is employed, the engaging sleeve is axially coincident with the rod and concentrically disposed external thereto (when the helical groove is external of the rod) or internal thereto (when the helical groove is internal of the rod). A spring is fixedly mounted within the frame, one end to the cutter assembly and the other end to the conversion means. The spring is so arranged that sliding rectilinear movement of the cutter assembly pushes against the spring to compress it when a pencil is inserted in the cutter assembly. Moreover, when a pencil is withdrawn, or when the inserting force is released, the spring returns to its initial position which, in turn, returns the cutter assembly to its initial position. In the embodiments of applicant's invention wherein cleaning or finishing of the pencil point occurs during the withdrawal of the pencil from the cutter assembly, it is the uncoiling axial force of the spring which imparts the rotational movement to the cutter assembly via the conversion means. A coupling means comprised of two halves is employed, a first half being slidable and rotatable with the rod and the second half being slidable and rotationally stationary. Each of the halves have claws which can be engaged or disengaged. When the two coupling halves are connected or engaged, the coupling halves become kinematically unitary. When the two coupling halves are disconnected or disengaged, the coupling halves are kinematically separate. The claws permit locking of the two coupling halves in one sense of rotational movement only. In the opposite sense of rotational movement, there is slipping but not locking of the two coupling halves. One half of the coupling means is mounted for slidable and rotatable movement with the rod and the other half is mounted for rotational movement only or no movement at all within the frame, i.e., in one embodiment, one coupling half is rotatably and slidable stationary. The two halves of the coupling means becomes connected as the spring is compressed and disconnect when the spring returns to its initial position. This invention accordingly consists of the features of construction, combination of elements, and arrangement of parts which will be exemplified in the preferred embodiments of the pencil sharpener hereinafter described and of which the scope of application will be indicated in the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS In the accompanying drawings in which are shown several of the various possible embodiments of the invention: FIG. 1 is a perspective view of a pencil sharpener in accordance with the present invention. FIG. 2 is a sectional elevation view of the pencil sharpener of FIG. 1 along lines 2--2 with a pencil inserted therein. FIG. 3a is a perspective view of the helically grooved rod designated by the numeral 36 in FIG. 2. FIG. 3b is a sectional elevation view of the helically grooved rod 36 of FIG. 3a taken along lines b--b. FIG. 3c is a plan view of the helically grooved rod 36 of FIGS. 3a and 3b taken along lines c--c. FIG. 4a is a perspective view of the engaging member designated by the numeral 38 in FIG. 2. FIG. 4b is a sectional elevation view of the engaging member 38 of FIG. 4a taken along lines b--b. FIG. 4c is a plan view of the engaging member 38 of FIGS. 4a and 4b taken along lines C--C. FIG. 5 is an enlarged perspective view partially in sectional elevation of the internals of the pencil sharpener of FIGS. 1 and 2. FIG. 6 is a perspective view partially in sectional elevation of the pencil sharpener in another embodiment of this invention. FIG. 7 is an enlarged view partially in sectional elevation of a portion of a double criss-crossing helically grooved rod 236 and double coupling members of the pencil sharpener in still another embodiment. FIG. 8 is an enlarged view in perspective of the upper engaging member of FIG. 7 threaded onto a portion of the double criss-crossing helically grooved rod 236. FIG. 9 is an enlarged view in sectional elevation of the lower engaging member in perspective threaded onto a portion of the double criss-crossing helically grooved rod 236 of FIG. 7. FIG. 10 is a perspective view partially in sectional elevation of the lower engaging member 238b. FIG. 11a is a perspective view partially in sectional elevation of the pencil sharpener in a further embodiment of this invention with sleeve 332 internally grooved helically. FIG. 11b is an enlarged perspective view of the rod and coupling members in FIG. 11a. FIG. 11c is an enlarged sectional elevation view of the rod and coupling members of FIGS. 11a and 11b. FIGS. 12a, 12b and 12c are perspective views of the internals of three alternate embodiments of a pencil sharpener according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to FIGS. 1, 2 and 5, a pencil sharpener 10 is shown comprised of hollow cylindrical housing 12. A lower portion of housing 12 designated by the numeral 14 defines a hollow, preferably transparent chamber 16 for receiving pencil shavings. An upper portion of housing 12 designated by the numeral 18 has an inner, hollow, cylindrical sleeve 20 integrally mounted thereto, sleeve 20 and housing 12 being coaxially aligned and axially coincident. The space between sleeve 20 and housing portion 18 is for holding pencils that are to be sharpened. A hollow, cylindrical sleeve 22 is coaxially aligned with sleeve 20. The outer surface of sleeve 22 at its lower end is shown slidably mounted to the inner surface of sleeve 20 at its upper end (when both sleeves are in a vertical orientation). A hollow, cylindrical pencil alignment sleeve 24 is coaxially mounted within sleeve 22 and fixed in position via annular ring 25 mounted by means of screw threads or the like around sleeve 24 at the top of sleeve 22. Ring 25 holds sleeve 22 in position in the assembly and keeps sleeve 24 freely rotatable within sleeve 22. The outer pair of telescoping sleeves 20 and 22 define the core of the pencil sharpener. Situated within the core are cutter assembly 30, an inner pair of telescoping sleeves, inner and outer protective sleeves 32 and 34, respectively, a helically grooved rod 36, a helical groove engaging member 38, coupling members 40a and 40b and a spring 42. Cutter assembly 30 extends from pencil alignment sleeve 24. Outer protective sleeve 34 is rotatably mounted to and depends from cutter assembly 30. Protective sleeve 34 is also coaxially aligned with cutter assembly 30. Also depending from cutter assembly 30 is the helically grooved rod 36 which is situated within outer protective sleeve 34 and extends into inner protective sleeve 32. The rod 36 and cutter assembly 30 are both mounted so as to be kinematically unitary within outer protective sleeve 34. The rod 36 and the inner and outer protective sleeves 32 and 34 are all coaxially aligned. Inner and outer protective sleeves 32 and 34 are slidable telescopically with respect to each other. The helically grooved rod 36 has threaded thereon helical groove engaging member 38, the lower portion of which is integrally formed with a claw coupling member 40a comprising the upper half of coupling assembly. The claw coupling member 40a is slidably and rotatably held stationary within sleeve 32 by engagement with claw coupling member 40b, which is fixedly mounted within inner protective sleeve 32 to the inner walls thereof. Spring 42 is shown fixed in position and concentrically wound about rod 36 (with sufficient clearance between them) within outer protective sleeve 34. One end of spring 42 is fixedly connected to the inner top of sleeve 34 and the other end of spring 42 is fixedly connected to the top of sleeve 32 (which holds sleeve 32 in position within the assembly). At the lower end of helically grooved rod 36 is fixedly attached a screw 41 or the like with a head larger than the opening where the helically grooved rod 36 passes through coupling member 40a and ring 39 so as to prevent the assembly from being dismantled due to the spring's expansive force. To the base of the inner protective sleeve 32 is fixedly attached support struts 43 which are also fixedly attached to the lower inner portion of outer sleeve 20. These support struts 43 or support legs should have enough clearance from telescopic sleeve 22 so as not to obstruct the movement of telescopic sleeve 22 and prevent the full movement of helically grooved rod 36 through the engaging member 38. At the base of the cylindrical housing 12 (14) there are one or more gripping pads 44 such as rubber pads to hold the pencil sharpener 10 stationary by friction forces when placed on top of a surface. When a pencil 4 is inserted into the sharpener 10 of FIGS. 1, 2 and 5, it is aligned within the cutter assembly 30 via alignment sleeve 24. The downward insertion force of the pencil 4 forces the cutter assembly 30 and rod 36 to slidably move in a substantially vertically downward direction. As the rod 36 moves in such direction, the coupling members 40a and 40b lockably connect and arrest rotational and slidable movement of engaging member 38 thereby forcing the rod 36 to rotate via action of engaging member 38 in a counter-clockwise rotation along its helical groove. This, in turn, causes the cutter assembly 30 to simultaneously rotate in a counter-clockwise rotation. As the cutter assembly 30 rotates in a counter-clockwise rotation, a blade means 31 situated therein spins about one end of the longitudinal sheath of pencil 4 sharpening such end into a conically shaped point. The pencil shavings fall out of cutter assembly 30 down between the inner wall of sleeve 22 and outer wall of protective alignment sleeve 34 and pass between the inner wall of sleeve 20 and outer wall of alignment sleeve 32 and pass the support struts 43 and into the hollow transparent chamber 16 of lower portion of housing 12. As can be easily visualized from FIGS. 3a, 3b, 3c, 4a, 4b and 4c, helically grooved rod 36 and engaging member 38 can be meshed together by means of complementary fitted sections of the rod 36 and engaging member 38 which typically thread together. The cross-section of rod 36 (see FIG. 3c) meshes within a mating cross-sectional opening in engaging member 38. A set of two complementary grooves are used for torsional balance. Referring to FIGS. 4a and 4b, it can be seen that one end of engaging member 38 (the lower end in this embodiment) may be formed so that it terminates in a claw-type coupling member 40a. During rotation and slidable movement of outer protective sleeve 34 downward relative to stationary inner protective sleeve 32, spring 42 is compressed. As the pencil 4 is withdrawn from the cutter assembly 30, spring 42 is allowed to expand and substantially return to its initial position. Expansion of the spring, in turn, causes the cutter assembly 30 to return to it initial position. While the cutter assembly 30 is being returned to its original position, coupling member 40a rides upward on the upward moving rod 36. This is due to the upward vertical force transmitted to the helically grooved coupling member 40a by the slope of the helical grooves of helically grooved rod 36. Consequently, coupling member 40a disconnects from slidably stationary coupling member 40b. Rotation of cutter assembly 30 and rod 36 (and sharpening of the pencil 4) are thus arrested during reverse movement of the cutter assembly 30 and rod 36 to their initial positions in this embodiment Referring now to FIG. 6, there are shown upper and lower claw-type coupling members 150a and 150b, respectively. When coupling member 150a and coupling member 150b are connected, they form a kinematically unitary coupling assembly. Upper coupling member 150a is fixedly mounted to ring 137. Both coupling member 150a and ring 137 have cross-sectional central openings therein sufficiently large to permit passage of rod 136 therethrough. Ring 137 is fixedly mounted to inner protective sleeve 132 with its plane transverse to the longitudinal axis of sleeve 132. The helical grooves of the helically grooved rod 136 in this embodiment are in an opposite direction to that of the helically grooved rod 36 in FIG. 5 and the engaging member 138 of this embodiment (FIG. 6) threads the oppositely directed helical grooves. Lower coupling member 150b is formed at the upper end of engaging member 138 which has a cross-sectional opening that meshes with rod 136 as described previously herein for rod 36 and coupling member 38. Coupling member 150b and engaging member 138 form a unitary piece which is slidably and rotatably mounted within inner protective sleeve 132 that is telescopible into sleeve 134. Ordinarily, the pitch of the helical groove on the rod 136 will allow for facile meshing and engaging member 150b will, by force of gravity, spiral down until stopped and supportably held by ring 139. Ring 139 also has a cross-sectional opening therein sufficiently large to permit passage of rod 136 therethrough and is fixedly mounted to inner protective sleeve 132 with its plane transverse to the longitudinal axis of sleeve 132. When the pencil 4 is inserted into pencil alignment sleeve 124 and cutter assembly 130, rod 136 and cutter assembly 130 do not rotate since the one-way coupling assembly slips but does not connect in the direction of pencil insertion. Since engaging member 138 is not held rotatably stationary with respect to rod 136, rod 136 is not forced to rotate. Sleeve 132 is secured to support struts 143. When the pencil is withdrawn from the cutter assembly 130 or the downward force released, the expansion of spring 142 forces the rod 136 and cutter assembly 130 backward to their respective initial positions. Engaging member 138 rides along with rod 136 until coupling member 150b connects with slidably and rotatably stationary coupling member 150a so that the two become kinetically unitary. The rectilinear slidable movement of rod 136 returning to its initial position relative to the rotatably stationary engaging member 138 forces the rod 136 and cutter assembly 130 to rotate. The rotation of cutter assembly 130 does not sharpen the pencil effectively because the expansive force of spring 142 is not sufficient to do this. However, it does cause the cutter blade 131 to lightly strike the pencil point and remove any remaining loose pencil shavings, thereby providing for a cleaner or finished pencil point. Referring to FIG. 7, there is shown still another embodiment of applicant's invention which is similar in construction and operation to the embodiments shown in FIGS. 1-5 and 6 except that two separate one-way coupling assemblies are employed and a combination of function is the result. A first coupling assembly comprised of coupling members 240a and 240b lockably connects when a pencil is inserted into the cutter assembly 230. These coupling members 240a and 240b are the same as the coupling members 40a and 40b previously described herein. As the pencil is inserted, engaging member 238a and claw-like coupling member 240a are forced down onto lower coupling member 240b which is fixedly mounted within inner protective sleeve 232 on the plane of ring 267, which plane is transverse to the longitudinal axis of the inner protective sleeve 232. The outer periphery of ring 267 is fixedly mounted to the inner wall of sleeve 232. Once the coupling assembly is connected, rotation of the rod 236 and cutter assembly 230 occur in a kinetically unitary counter-clockwise rotation as previously described herein. In a like manner, coupling members 250a and 250b form the coupling assembly which lockably connects when the pencil is withdrawn from the pencil sharpener. The latter coupling assembly operates as described with respect to the coupling assembly shown for FIG. 6. When one coupling assembly of the double coupling assembly shown in FIG. 7 is engaged, the other one is always disengaged and vice versa. Also, when a double coupling assembly is employed, the rod 236 has two criss-crossed symmetrically disposed helically shaped grooves thereon, one set of helically parallel grooves for each of the engaging members 238a and 238b. Engaging member 238a rides in one set of the two helical grooves and engaging member 238b rides in the other and the threads of each engaging member are sufficiently long so that they remain in only one helical groove and never cross into the other helical groove. Referring to FIG. 8, there is shown engaging member 238a which when fixed in position within the inner protective sleeve 232 by locking connection of coupling members 240a and 240b causes the rod 236 to rotate counter-clockwise slidably moving in a substantially vertically downwards direction; engaging member 238a remains meshed with one set of the two helical grooves of rod 236. Similarly, referring to FIG. 9, there is shown a second engaging member 238b meshed with the other set of the two helical grooves of rod 236. When fixed in position relative to the slidably moving rod 236 via the locking connection of the second set of coupling members 250a and 250b, engaging member 238b causes rod 236 to rotate counter-clockwise while slidably moving in a substantially vertically upwards direction; engaging member 238b also remains meshed with the other of the helical grooves of rod 236. FIG. 10 illustrates the elongated transverse helical "teeth" 235 of one of the engaging members 238b. The elongated "teeth" ensure that engaging member 238b remains meshed with the one of the helical grooves in rod 236 with which it is already meshed. Referring now to FIGS. 11a, 11b and 11c, still another embodiment of the present invention is illustrated wherein rod 366 (comprised of rod portions 366a and 366b) is not helically grooved. Instead, rod element 366b has an engaging means 368 having an outer helical groove. Inner protective alignment sleeve 332 has a helical groove on its inner channel which meshes with engaging means 368. Engaging means 368 is concentrically mounted and axially coincident external to rod 366b. Claw-type clutch halves 370a and 370b are employed to transmit rotational movement of rod element 366a to rod element 366b. When clutch members 370a and 370b are connected, rod 366 is kinetically unitary. When clutch members 370a and 370b are disconnected, a reduced diameter segment 366c (guide pin) of rod element 366a is rotatably stationary but axially slidable within outer protective sleeve 334 and rod element 366b is rotatable within inner protective sleeve 332. When a pencil is inserted into cutter assembly 330, the cutter assembly 330 and rod 366a do not rotate immediately within the outer protective sleeve 334 but slidably move vertically downward until coupling members 370a and 370b are connected with one another. When coupling members 370a and 370b are rotatably unitary, the rotational movement of rod element 366b is transmitted to rod element 366a via clutch members 370a and 370b. Spring 342 operates as discussed previously herein to disconnect clutch members 370a and 370b when a pencil is withdrawn from cutter assembly 330 or when a downward force is released. The same two criss-crossing grooves can be incorporated in alignment sleeve 332 of this embodiment with a correspondently threaded engaging means 368. In FIGS. 12a, 12b and 12c, cutter assembly 430 is fixedly held by a slidable upright carriage 75. The carriage 75 is slidably mounted within a channel 77 along the base of horizontal support member (frame) 80 having an upright arm 82. Guide pin 86 is coaxially aligned with cutter assembly 430 and fixedly mounted thereto. Clutch members 270a and 470b are also coaxially aligned with guide pin 86 and concentrically disposed external thereto. Spring 442 is fixedly mounted between one end of guide pin 86 and the upright arm member 82. Referring to FIG. 12a, there is shown a circularly shaped gear 88 having helical grooves about its perimeter which are meshed with corresponding diagonal grooves 89 on the upper surface of horizontal track means 90 mounted transverse to gear 88 on the support member 80. As a pencil is inserted into cutter assembly 430, the carriage 75 slides along channel 77 within the support member 80 in the direction of insertion and coupling means 470a engages coupling means 470b. The teeth of the circular gear 88 mesh with the diagonal grooves 89 to turn the gear 88 which is concentrically mounted and externally disposed on clutch member 470b. When rotating clutch member 70b rotates clutch member 470a which is fixedly mounted to cutter assembly 430, cutter assembly 430 rotates. When the pencil is withdrawn, spring 442 causes rotatable clutch member 470a to return to its initial position but it is disengaged from rotating clutch member 470b so cutter assembly 430 does not rotate. Referring to FIG. 12b, there is shown an embodiment similar to that of FIG. 12a, except that a circular bevel gear 94 drives a second smaller bevel gear 92 threaded therewith. Bevel gear 94 is rotatably mounted to carriage 75. Bevel gear 92 is fixedly mounted to coupling member 470b and is rotatably mounted to carriage 75 holding coupling members 470a and 470b. Thus, rotation of the bevel gear 92 causes rotation of the coupling member 470b. The sliding part of this embodiment is the cutter assembly 430 itself. When a pencil is inserted into the cutter assembly 430, the cutter assembly 430 moves in the direction of insertion along with the guiding pin 86 affixed thereto and coaxially aligned therewith. When the two clutch members 470a and 470b are engaged, the turning of the bigger bevel gear 94 drives the smaller bevel gear 92 which, in turn, causes the cutter assembly 430 to rotate. Friction gears can be used in this embodiment whereas tooth gears must be used in the FIG. 12a embodiment. The bigger bevel gear 94 is caused to rotate by the same principles described with respect to the circular gear of FIG. 12a. When the pencil is withdrawn, spring 442 pushes the carriage 75 back to its initial position via the guiding pin 86 as the clutch members 470a and 470b disengage. Referring now to FIG. 12c, there is shown an embodiment similar to that shown in FIG. 12b, except that a cable 95 is attached to a circular gear 96, a rack and pinion type gear. The rack 97 is mounted on the track means 90. The clutch members 470a and 470b operate as described previously with respect to FIG. 12b, except that coupling member 470a is rotatably nonslidably connected to guiding arm 99 and spring 442 is mounted between upright arm 82 and guiding arm 99 which extends slidably through carriage 75. When the coupling members 470a and 470b are forced to engage, as the pencil is inserted into the cutter assembly, arm 99 compresses spring 442 and carriage 75 is moved in the direction of pencil insertion, and the teeth of the pinion gear 96 engage the grooves 97 within the rack 90 rotating the pinion gear 96 and cable 95 attached thereto. The cable 95, in turn, causes the rotatable clutch member 470b to rotate and simultaneously rotate coupling member 470a. The rotation of the cable 95 is transformed into corresponding rotation of the cutter assembly 430 which sharpens the pencil. When the pencil is withdrawn, spring 442 causes the carriage 75 to return to its initial position wherein the clutch members 470a (FIGS. 12a, 12b, 12c) and 470b are disengaged. In the three embodiments shown in FIGS. 12a, 12b and 12c, the support members must be fixed to a stable substrate in order to operate. The spring 442 returns all of the gears to their initial position when the pencil is withdrawn. When constructing the various embodiments of the present invention, suitable materials should be employed keeping in mind their strength and low coefficient of friction. Preferably plastics such as nylons and acetals can be used for mechanical moving parts, and polystyrene, acrylonitrile-butadrene-styrene and acrylics can be used for the housing for economical reasons; they are relatively inexpensive materials. Metals such as aluminum and steel can also be used. The helical slopes of the helical grooves should be at an angle for efficient use of the axial forces associated with the pencil sharpener of this invention. Steeper slopes will increase the axial distance that has to be traveled for a desired rotation. This will reduce the force required to operate the pencil sharpener but increase the number of axial movements required to sharpen a pencil. Slopes which are not steep enough will require greater axial force for operation but there will be more rotations of the cutter assembly per axial distance traveled. The mechanical advantage, however, would shift to the pencil sharpener and away from the user. In addition to the steepness of the helical slope, the diameter of the helix also influences the efficiency of the pencil sharpener. Wider diameters require more force to operate the sharpener. Smaller diameter helices are preferred provided structural strength is not sacrificed. Also, extreme insertion forces could jam the pencil in the cutter assembly and damage the pencil and possible the cutter assembly as well. Although the rotating direction of the helically grooved rod 36 has been herein described as being counter-clockwise, it should be kept in mind that the construction of this invention should be such that the rod 36 rotates in a direction that would drive the cutter assembly functionally. The tension of spring 42 should be just enough to return the pencil sharpener to its initial position prior to insertion. A high tension spring, therefore, should not be used. Various types of cutter assemblies may be used providing that they operate in a rotating movement in order to sharpen a pencil. A simple blade cutter assembly is used in the embodiments herein described. However, within the scope of this invention several such blades or a milling or abrading cutter assembly may be used. In the rotatable contact parts shown in FIGS. 1-5, such as between pencil alignment sleeve 24 and sleeve 22, a washer or ball bearing or the like may be used to reduce friction. This friction reducing device can be placed between ring 25 and the cutter assembly 30. The same can be done between the rotating contacts of helically grooved rod 36 and protective alignment sleeve 34 and also between the rotating contacts of rod 36 and engaging sleeve 38. The same comments apply to the corresponding parts of the other embodiments. Due to this invention's compact and simple construction, a variety of housing designs can be incorporated. Also, due to the fact that it has no externally protruding wires, cranks or clamps, all that is needed in these housing designs is that they have an opening to insert the pencil. In some designs, telescopic means can be employed, as previously described herein, while in other designs, the pencil can be inserted deeply into the pencil sharpener housing (with a non-movable telescopic housing design) and the inner working parts move with the pencil and sharpen it. For example, a vase can have an opening on its top end for the pencil to be inserted. The pencil is inserted in the opening which is also the opening of the cutter assembly and, as the insertion continues, the pencil with the cutter assembly, sinks into the vase and sharpens the pencil. It thus will be seen that there is provided a pencil sharpener which achieves the various objects of the invention and which is well adapted to meet the conditions of practical use. As various possible embodiments might be made of the above invention, and as various changes might be made in the embodiments set forth, it is to be understood that all matter herein described or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense. Thus, it will be understood by those skilled in the art that although preferred and alternate embodiments have been shown and described in accordance with the Patent Statutes, the invention is not limited thereto or thereby.
A mechanical pencil sharpener including a housing with a cutter assembly adapted to receive the end of a pencil along its longitudinal axis. The manual force associated with inserting a pencil into the cutter assembly causes the cutter assembly to slidably move along its longitudinal axis within the housing. Engaging means responsive to the axial slidable movement of the cutter assembly translates such slidable movement into simultaneous rotational movement of the cutter assembly. A spring is used to return the cutter assembly to its initial position when the pencil is withdrawn therefrom. A coupling means responsive to axial slidable movement of the cutter assembly in a forward or backward direction or both is employed to selectively actuate the engaging means.
8
CROSS-REFERENCE TO RELATED APPLICATIONS This application is a continuation of U.S. patent application Ser. No. 14/202,779 filed Mar. 10, 2014, which claims the benefit of U.S. Provisional Application No. 61/775,737 filed Mar. 11, 2013. All of the foregoing are incorporated by reference in their entireties. FIELD OF THE INVENTION Embodiment disclosed herein relate to systems using near field communication (NFC) technology for digital devices connected to a local network. BACKGROUND Near Field Communication Technology, known by the acronym “NFC”, is a wireless, high frequency communication technology having a range of a few centimeters intended to exchange information between several peripherals. This technology results from a combination of a contactless chip card interface and a reader in a single device. An NFC peripheral can communicate with other NFC peripherals as well as with other devices meeting ISO 14443 standards such as e.g., contactless chip cards. The NFC standards covering communication protocols and data exchange formats are based on existing radio frequency identification standards (RFID) such as ISO/IEC 14443, FeliCa and ISO/IEC 18092. They include the standards defined by the “NFC Forum” founded in 2004 by Nokia, Philips and Sony comprising today more than 180 members. NFC technology is an extension of RFID technology, allowing bidirectional communications between two peripherals, while previous systems, such as contactless chip cards, allowed only unidirectional communication. NFC technology is usable only over a short distance of about a few centimeters, which implies a voluntary process from the user by preventing a usage without his knowledge. NFC devices may be passive or active. A passive device such as a tag, chip card or a single chip integrated in an object contains information accessible in a read only mode by other NFC compatible devices. The passive device is powered by the electromagnetic field emitted by the reader (active device) so that it does not need its own power supply. On the other hand, an active device generates the electromagnetic field for communicating with a passive device or for establishing a communication channel between two active devices. The fact that a device like a smartphone has a power supply does not necessarily mean that it will work in active mode only. A smartphone, or any other portable device like a PDA (Personal Digital Assistant) or a digital tablet, may process its NFC interface in a passive or active mode. In a passive mode, the smartphone emulates a chip card and stores, in a secure memory, the information usually stored in the chip card. Thus, when the smartphone detects the electromagnetic field, it will access the secure memory and answer in a passive NFC mode with the information read from this secure memory. The following are examples of known applications that use NFC technology: Payment using a contactless bank card or a mobile device (e.g., smartphone, portable computer, digital tablet, PDA, etc.) on a contactless payment terminal; Parking payment on a terminal accepting contactless payment carried out with a portable phone; Buying and contactlessly validating a ticket for transportation or a show with the smartphone or other mobile device; Managing discount vouchers in a shop, couponing by traders, etc; Accessing and starting a vehicle with a portable phone or other mobile device; Reading product information (e.g., price, composition, usage, etc.) in a shop; Controlling physical access to reserved places (e.g., meeting rooms, company, class rooms, etc.) Exchanging profiles between two users of a social network or game by bringing phones close together (e.g., user peer-to-peer communications); Reading electronic business cards with a mobile terminal or PDA; Synchronizing Internet bookmarks and contacts between a PDA and a portable phone; Retrieving a key or code to a WiFi access point by approaching an NFC mobile terminal to the emitting hotspot; and Accessing different automation functionalities of a building (e.g., home automation) NFC systems are designed to enable communication between devices that are positioned close to each other. However, sometimes this may be cumbersome within e.g., a home or a home network in which users wish to access additional functions offered through an NFC link, even if the distance between the devices is greater than the usual NFC communication distance. SUMMARY An object of the embodiments disclosed herein is to extend NFC communications between an NFC device and an NFC mobile device beyond the range defined by the NFC standards. This object is achieved by a system comprising: at least two repeater devices, each repeater device comprising a first communication interface configured to exchange information within a local communication network and a second communication interface locally connected to the first communication interface, the second communication interface comprising an NFC transceiver configured to exchange digital data intended to be transferred to the local communication network via the first communication interface; a stand alone device associated with a first repeater device, the stand alone device comprising an NFC communication interface coupled with the NFC transceiver of said first repeater device; and a mobile device comprising an NFC communication interface configured to exchange digital data with an NFC transceiver of a second repeater device, said second repeater device being configured to forward, to the local communication network, the digital data received from the mobile device via the NFC communication interface, said digital data being transmitted to the stand alone device via the first repeater device, said first repeater device being at a distance from the second repeater device exceeding a standard range for NFC communications. The data read by the second repeater device through the NFC communication interface of the mobile device is thus transferred to the stand alone device due to the local communication network to which the first repeater device is connected to. The stand alone device may thus be located a long distance away from the NFC featured mobile device and still receive data in a manner similar to the manner offered by direct NFC communications (i.e., as if the mobile device was located only a very small distance away from the stand alone device). This solution uses bi-directional NFC repeater devices connected to the local communication network, each being provided with NFC communication capabilities. For example, a home or a household is equipped with several repeater devices; each repeater device comprises a mechanism for communicating with at least one other repeater device, such that all of the repeater devices of the home network are connected together. The communication can be made through several means such as e.g., WiFi, Internet, radio frequency, power lines (PLC Power Line Carrier) or any other technology with a longer communication range than the NFC standard range. Each repeater device comprises NFC capabilities such that the digital data comprising commands or instructions from an NFC mobile device can be read by at least one repeater device if the NFC mobile device is placed close to the repeater device. The repeater device receiving command data from an NFC mobile device forwards said command data to any other repeater device of the home network through the home network. Thus, a single NFC mobile device can be used to communicate with other devices (e.g., stand alone devices) of the home network even if the NFC mobile device is located a distance away from the stand alone devices. BRIEF DESCRIPTION OF THE DRAWINGS The embodiments disclosed herein and their advantages will be better understood with reference to the enclosed drawings and the following detailed description, in which: FIG. 1 shows a block diagram of a repeater device comprising a LAN and NFC communication interfaces FIG. 2 shows a block diagram of a system according to a disclosed embodiment comprising a plurality of repeater devices connected to a local network allowing the transfer of data from an NFC mobile device to a distant device via repeater devices placed respectively close to the mobile device and to the distant device. FIG. 3 shows a block diagram of an embodiment of the system disclosed herein comprising a gateway configured to forward information from one repeater device to another. DETAILED DESCRIPTION A repeater device R is schematically illustrated in FIG. 1 as comprising a first communication interface CI 1 able to exchange data with a local network LAN and a second communication interface CI 2 able to communicate with an NFC device via an NFC transceiver. The first and the second communication interfaces are locally connected together so that data received from the second communication interface CI 2 or NFC interface are transferred to the first communication interface CH or LAN interface and vice-versa. In addition, the LAN interface may transmit data coming from the local network back to the NFC interface. According to a desired configuration, repeater devices R 1 , R 2 , R 3 , R 4 are connected to each other in a bidirectional local network LAN via their first communication interface CI 1 as illustrated by FIG. 2 . The system of the invention comprises a set of repeater devices each associated with a stand alone device and a set of repeater devices configured to communicate with a mobile NFC device. In the example of FIG. 2 , the system comprises repeater devices R 1 , R 2 , R 3 , R 4 , . . . whose second communication interface CI 2 or NFC interface may be linked either to at least one NFC mobile device P or at least one stand alone device D 1 , D 2 having NFC capabilities. The local network LAN is preferably wireless using a standardized radio frequency connection such as defined in Wi-Fi standard, but it may also be wired using a standard cable connection such as e.g., Ethernet links, or hybrid using a combination of wireless and wired connections. The mobile NFC device P may comprise a smart card of a passive or active type, smartphone, PDA, tablet, remote control or any other potable or hand held device adapted to transmit data to a repeater device R 1 , R 2 , R 3 , R 4 , . . . of the LAN network. An active smartcard as described in e.g., U.S. Pat. No. 7,128,274 is provided with an internal power source that generates an electromagnetic field for communicating with the repeater device R 1 , R 2 , R 3 , R 4 , . . . . A passive smart card acts as an RFID device powered by an electromagnetic field generated by the repeater device. The other mobile NFC devices (e.g., smartphone, tablet, PDA, etc.) may be set to either the passive or active mode. The stand alone devices D 1 , D 2 may comprise a fixed appliance provided with an NFC communication interface placed near a repeater device R 1 , R 2 , R 3 , R 4 , . . . at a distance within the NFC range (e.g., up to 10 cm). A connection between the stand alone device D 1 , D 2 and the LAN network communication interface is thus facilitated since communication is possible via the repeater device. For example, in a home network, devices such as a television set, decoder or set top box, DVD and/or HD (hard disc) reader/writer, media player, personal computer, security alarm, heat controller, air conditioner, etc. may be activated/deactivated or controlled with via an NFC connection with a repeater device R 1 , R 2 , R 3 , R 4 , . . . . In the system represented by FIG. 2 , a portable NFC device P sends, via the NFC link of repeater device R 2 , digital data in form of a command addressed to stand alone device D 1 associated with repeater device R 1 and/or to stand alone device D 2 associated with the repeater device R 4 . The following transmission modes may be used to forward the command: a) Broadcast mode: all repeater devices R 2 , R 3 , R 4 receive the same command without a specific identifier of a repeater device or of a stand alone device D 1 , D 2 . In this case, the NFC transceiver of the repeater device sends an interrogation signal to test a presence of a stand alone device within the NFC range. If such a device is present, its NFC communication interface replies to the interrogation signal with a response signal informing the repeater device that the stand alone device is ready to receive the command. The broadcasting mode thus allows activating several stand alone devices D 1 , D 2 at a same time, with a portable NFC device P, if they are placed near a repeater device R 1 , R 4 of the LAN network and their NFC interface is powered on. The broadcast mode allows using an NFC featured smart card in a passive mode, which may be read by any repeater device in the network to automatically send a command to one or more other repeater devices R 1 , R 4 , and to their associated stand alone devices D 1 , D 2 . b) Push mode: a command is addressed to a specific stand alone device while the other stand alone devices ignore the command even if they are placed within the NFC range and have an NFC interface powered on. In this case, the command comprises a device identifier and/or an identifier of the repeater device to which a stand alone device is associated with. After checking the identifier of the command, the NFC transceiver of the repeater device forwards the command to the stand alone device only when a match is found with the identifier of the repeater device or the identifier of the stand alone device. The push mode requires a user interface on the mobile NFC device allowing the selection of a specific stand alone device to be controlled with a command. For example, in a system setup phase all repeater devices and associated stand alone devices may be registered with their particular parameters in an application. A user can thus create and address specific commands to a specific stand alone device. The NFC interface of the mobile device is preferably used in active mode. According to an embodiment, the application on the mobile device may also be allowed to create predefined groups of stand alone devices to which a same command can be addressed. c) Pull mode: the mobile NFC device P interrogates a repeater device to detect active stand alone devices associated with the other repeater devices of the network. Once one or more active devices are detected, commands may be sent to these devices either in broadcast mode or, individually, in push mode. In this case, a first repeater device of the network is requested by the mobile device to explore the network and discover each active repeater device, which are requested in their respective turn to send an interrogation signal to an associated stand alone device, if any. The responses of the stand alone devices received by the repeater devices are forwarded to the network and read by the mobile NFC device in contact with the first repeater device. An application of the mobile device identifies each discovered stand alone device and creates a list allowing the selecting and activating, deactivating or controlling of a stand alone device by a specific command addressed to one device or a common command addressed to all or a group of devices. According to a further embodiment, the mobile NFC device P may be provided with an application allowing it to send commands to the stand alone devices either in broadcast, push, or pull mode, or a combination of these modes, depending on a mode selection made on the user interface. According to a further embodiment illustrated in FIG. 3 , each repeater device R 1 , R 2 , R 3 , R 4 may be connected to a gateway G server in charge of managing the bidirectional communications between the repeater devices of e.g., a local network LAN. The connection between the repeater devices and the gateway G may be wireless, wired or mixed as in the network configuration of FIG. 2 . The above discussed transmission modes are also operable in this embodiment since they do not depend on the configuration of the local network. According to a further embodiment, an acknowledgement message may be returned to the mobile NFC device when the command has been received and/or executed successfully by one or more stand alone devices associated with their respective repeater device. As the NFC communication technology has a short range of up to 10 cm, the repeater device and the mobile NFC device or the stand alone device must be close to one another so that encryption of the transmission is in general not necessary. However, for high security purposes, the transmission may be encrypted using a pairing mechanism between the concerned devices. The pairing may be applied as described for example in the European document EP1078524B1. The command transmitted from the repeater device to the stand alone device is encrypted by a unique pairing key known by the repeater device and the stand alone device. The latter verifies the pairing with the repeater device preferably at each reception of a command. If the pairing verification is successful, the command is executed by the stand alone device. An advantage of this pairing feature is that it prevents associating an unauthorized stand alone device to a repeater device. A similar pairing mechanism may also be applied between the mobile NFC device and each repeater device of the network. In this case, the mobile NFC device stores all of the necessary pairing keys in order to be able to communicate with any repeater device of the local LAN network. An advantage of this pairing feature is that it prevents communications between a repeater device and an unauthorized mobile device. In order to save power, an NFC communication between a repeater device R 1 , R 4 and an associated stand alone device D 1 , D 2 , as well as the communication between the mobile NFC device and a repeater device, is deactivated after successful transmission of the command. In the case of an unsuccessful transmission, the NFC communication is deactivated after a predetermined time. It should be appreciated that a stand alone device can also receive a command directly from the NFC mobile device when it is placed close to the NFC interface.
A system for a local network, the system being configured to extend a near field communication (NFC) between an NFC device and an NFC mobile device beyond the range defined by the NFC standards.
7
BACKGROUND OF THE INVENTION This invention relates to a method for commercially cleaning area rugs such as throw rungs and oriental rugs. There are known methods, systems and apparatuses for commercially cleaning area rugs, but none that teach the effectiveness, convenience, rug protection and low cost made possible by this invention. An example of a different method and an apparatus is described in U.S. Pat. No. 4,453,386, issued to Wilkins on Jun. 12, 1984. With the Wilkins system, rugs are positioned upside down on a conveyor belt and sprayed angularly upward into carpet fiber and downward onto carpet backing with cleaning fluid from a plurality of diversely directed nozzles for dirt removal, rinsing and drying while the rugs are being conveyed across a top of a plurality of successively washing and drying portions of a rectangular tank. Wilkins taught a general-purpose rug-washing system that does not allow sufficient flexibility of professional cleaning techniques required for different types of rugs. Nor does it provide sufficient dry particle removal, washing action, deodorizing, dry cleaning and fabric conditioning for most types of rugs. It has limited effectiveness for some types of rugs and is damaging to others. SUMMARY OF THE INVENTION Objects of patentable novelty and utility taught by this invention are to provide a rug-cleaning method which: provides for application of required select professional knowledge for cleaning all types of rugs by commercial rug cleaners; removes all types of dirt, odors and stains effectively from all portions of all types of rugs; protects rug nap, backing and fringes; and reconditions rug materials. This invention accomplishes these and other objectives with a rug-cleaning method having steps of first removing dry particles with a pressurized angular blower that removes forms and concentrations of particulate which can be removed most effectively dry than wet and which would deter effective cleaning with liquid cleaning agents first. Second is immersion shampooing in a tank of shampoo solution that is agitated, strained, circulated, flushed and replaced repeatedly as appropriate to remove a major portion of dissolved and undissolved dirt that is removable without scrubbing or rubbing. Third, while the rug is still wet and soaked from the shampoo, is scrub washing rotationally while deodorizing with a detergent solution that is selected from classes and types of cleaning agents for removal of relatively adherent contaminants such as urine, food stains, rust, oils and other common dirt that may be detected in particular rugs. Fourth is water rinsing top, bottom and any fringe. Fifth is vacuuming top, bottom and any fringe with an extractor. Sixth is drying at approximately 70 to 75 degrees Fahrenheit. Seventh is spray dry cleaning with a water-miscible solvent. Eighth is conditioning with an acid-based dry-cleaning catalyst. Finally, a ninth step is rubbing with a rotating cloth pad before the dry-cleaning catalyst is fully dry. The above and other objects, features and advantages of the present invention should become even more readily apparent to those skilled in the art upon a reading of the following detailed description in conjunction with the drawings wherein there is shown and described illustrative embodiments of the invention. BRIEF DESCRIPTION OF DRAWINGS This invention is described by appended claims in relation to description of a preferred embodiment with reference to the following drawings which are described briefly as follows: FIG. 1 is a flow diagram of the method with schematic representations of steps of the method; FIG. 2 is a side elevation view of a manual nozzle tube showing nozzle orifices for direction of air spray at angles to verticality of rug nap; FIG. 3 is a front elevation view of a nozzle tube with wheels for either manual or automated machinery for a dry-extractible step of the method; FIG. 4 is a partially cutaway end view of the FIG. 3 illustration; FIG. 5 is a partially cutaway end view of an immersion-shampoo tank with features for both manual and automated application of this method; FIG. 6 is a side view of a schematic representation of an automated application of this area-rug cleaning method; FIG. 7 is a partially cutaway side view of a section of a rug-conveyance system for the automated application of this area-rug cleaning method; and FIG. 8 is a partially cutaway top view of the rug-conveyance system of the FIG. 7 illustration. DESCRIPTION OF PREFERRED EMBODIMENT Listed numerically below with reference to the drawings are terms used to describe features of this invention. These terms and numbers designate the same features throughout this description. 1. Air spray 33. Tank rack 2. Rug 34. Air-spray section 3. Nap 35. Automated nozzle tubes 4. Backing 36. Vacuum hood 5. Fringes 37. Shampoo section 6. Sprays of air 38. Immersion tank 7. Nozzles 39. Shampoo wringer 8. Nozzle tube 40. Scrub-wash section 9. Immersion shampoo 41. Automated scrubbers 10. Shampoo tank 42. Vacuum section 11. Shampoo-liquid line 43. Automated vacuum 12. Inlet conveyance 44. Water-rinse section 13. Circulator 45. Automated rinse tank 14. Agitator tube 46. Water-rinse wringer 15. Drain conveyance 47. Cool-dry section 16. Scrub wash 48. Automated blow dryer 17. Rotary scrubbing brush 49. Blow-dryer hood 18. Vacuum extract 50. Dry-clean section 19. Extractor vacuum 51. Automated dry cleaner 20. Water rinse 52. Acid-condition section 21. Rinse tank 53. Conditioner tank 22. Rinse-water conveyance 54. Conditioning wringer 23. Cool dry 55. Pad-rub section 24. Dry clean 56. Automated rubbing machine 25. Acid condition 57. Top roller 26. Pad rub 58. Roller fingers 27. Cloth pad 59. Bottom roller 28. Rotational rubbing machine 60. Elongate spaces 29. Roundness orifices 61. Support belts 30. Flatness orifices 62. Strainer 31. Slanted handle 32. Nozzle-tube wheels Referring first to the flow diagram with schematic representation of this rug-cleaning method in FIG. 1, a first step is designated as air spray 1 for removing dry-extractible dirt from a rug 2 having nap 3 on backing 4 and generally fringes 5 . Sprays of air 6 are shown as being directed at approximately forty-five degrees from verticality of the nap 3 from nozzles 7 at optionally both sides of a nozzle tube 8 , but can be directed from only one side of nozzle tubes 8 for some applications. Unique advantages of air spray 1 as the first step include removal of particulate contamination that could spread to other parts of a rug and to other rugs if wet before being removed. In addition, dry particulate contamination consumes additional cleaning fluid and requires different types of cleaning agents for effectiveness than for dirt that can not be removed readily in dry form. The sprays of air 6 are directed from the nozzles 7 at approximately thirty-to-fifty degrees from verticality of the nap 3 in order to best reach under dry dirt and to protect the backing 4 from damage with a more direct angle. Pressure of air from the nozzles 7 is ninety to one hundred forty psi, as appropriate for structure of particular predetermined area rugs 2 . The sprays of air 6 are directed from at least two opposite sides of the nap 3 in order to remove dirt from all around separate strands of nap 3 . This can be accomplished by directing the sprays of air 6 from a single side of a nozzle tube 8 that is rotated approximately ninety degrees between a first and a second orientation angle of the nozzles 7 . Optionally, the nozzle tubes 8 can have nozzles 7 at both sides for being moved over the nap 3 for angular spraying oppositely from-side-to-side of the nap 3 . A second step is designated immersion shampoo 9 for removing immersion-extractible dirt with immersion-shampooing. For immersion-shampooing, the rug 2 is immersed in a shampoo tank 10 below a shampoo-liquid line 11 where shampoo liquid is added with an inlet conveyance 12 , circulated with a circulator 13 , agitated with shampoo jets from an agitator tube 14 and drained for replacement by a drain conveyance 15 and strained by a strainer 62 as appropriate for predetermined area rugs 2 . Immersion-shampooing avoids physical contact of objects such as scrubbers with the nap 3 and the backing 4 . The fringes 5 , however, can be scrubbed or otherwise washed aggressively as appropriate for the predetermined area rugs 2 in relation to the immersion-shampooing. A third step is designated scrub wash 16 for aggressively scrubbing the nap 3 and the fringes 5 as appropriate for removing adhered dirt such as stains, odors, urine and oil after removal of cleaning obstruction by dry-removable and immersion-removable contaminants. Then, cleaning agents that are particularly designed for absorbed and adhered dirt can be used effectively with scrubbing equipment such as a rotary scrubbing brush 17 . A fourth step is designated vacuum extract 18 for removing wash fluid, foam and dirt with preferably an extractor vacuum 19 . A fifth step is designated water rinse 20 for water rinsing of the rug 2 with preferably clean water in a rinse tank 21 having a rinse-water conveyance 22 . A spray or hose rinse can be used as an option. A sixth step is designated cool dry 23 for cool drying at approximately 70 to 75 degrees Fahrenheit. Cool drying can be hanging on racks for a curing period or blow drying with high volumes of air and dehumidification similar to spraying with air as described in relation to air spray 1 . A seventh step is designated dry clean 24 for dry cleaning to remove types of adhered dirt, stains and odors that are not removable fully with washing. Spray dry cleaning is preferred. Immersion dry cleaning is optional. An eighth step is designated acid condition 25 for conditioning with an catalyst to counteract or neutralize any residue of base substances in washing and dry-cleaning agents. This also can be accomplished optionally by spraying or immersion. A ninth step is designated pad rub 26 for rubbing the nap 3 with preferably a cloth pad 27 treated in an acid-based catalyst on a rotational rubbing machine 28 . Referring to FIGS. 1-4, the nozzles 7 are preferably a mix of roundness orifices 29 for controlled concentration of the sprays of air 6 and flatness orifices 30 for controlled flat sprays of air 6 from nozzle tubes 8 that can be supported by a slanted handle 31 as shown in FIG. 2 and/or that can be supported by nozzle-tube wheels 32 as shown in FIGS. 3-4. The nozzles 7 can be positioned on both sides of the nozzle tube 8 as shown in FIG. 4 or on one side as shown in FIG. 2 . Referring to FIGS. 1 and 5, the shampoo tank 10 can have a tank rack 33 on which to suspend rugs 2 below the shampoo-liquid line 11 while being immersion-shampooed as described in relation to FIG. 1 . Referring to FIGS. 1-8, this area-rug cleaning method can be applied with relatively manual equipment or relatively automated machinery, neither of which are intended to be described in detail for purposes of being claimed in this document. FIGS. 2 and 5 illustrate relatively manual equipment. FIGS. 3-4 and 6 - 8 illustrate relatively automated machinery that is implied also in the description in relation to FIG. 1 . Relatively automated machinery can include sections for cleaning of rugs 2 progressively with this area-rug cleaning method. The air spray 1 can be accomplished in an air-spray section 34 having automated nozzle tubes 35 that can extend lengths or widths of the air-spray section 34 and be provided with a vacuum hood 36 for removing dirt blown away by air from the nozzles 7 . The immersion shampoo 9 can be accomplished in a shampoo section 37 having conveyance of part or full lengths of rugs 2 progressively through an automated immersion tank 38 with the same shampooing features as described for FIGS. 1 and 5 and having a shampoo wringer 39 at a terminal end. The scrub wash 16 can be accomplished in a scrub-wash section 40 having conveyance of rugs 2 under automated scrubbers 41 that are preferably rotational as described for FIG. 1 . The vacuum extract 18 can be accomplished in a vacuum section 42 having conveyance of rugs 2 under an automated vacuum 43 . The water rinse 20 can be accomplished in a water-rinse section 44 having conveyance of rugs 2 through an automated rinse tank 45 , followed by a water-rinse wringer 46 . The cool dry 23 can be accomplished in a cool-dry section 47 having conveyance of rugs 2 under and/or through an automated blow-dryer 48 using high volume of air provided by air movers as used for drying. The dry clean 24 can be accomplished in a dry-clean section 50 having conveyance of rugs 2 under and/or through an automated dry cleaner 51 which can have either a sprayer or an immersion tank. The acid condition 25 can be accomplished in an acid-condition section 52 having conveyance of rugs 2 through an automated conditioner tank 53 which can be followed by a conditioning wringer 54 . The pad rub 26 can be accomplished in an pad-rub section 55 having conveyance of rugs 2 under an automated rubbing machine 56 onto which cloth pads 27 are positioned for rotational rubbing. Shown in FIGS. 7-8 for rug conveyance are recommended components which include a top roller 57 having roller fingers 58 with predetermined resilience and softness in combination with a bottom roller 59 having roller fingers 58 . The top roller 57 and the bottom roller 59 rotate in opposite directions with the roller fingers 58 having predetermined extension through elongate spaces 60 between rug-support belts 61 that can travel linearly to convey area rugs 2 in cooperation with the rollers 57 and 59 . Appropriate positioning, sizing, and shaping of these components can be provided for the sections of the relatively automated machinery shown in FIG. 6 . A new and useful area-rug cleaning method having been described, all such foreseeable modifications, adaptations, substitutions of equivalents, mathematical possibilities of combinations of parts, pluralities of parts, applications and forms thereof as described by the following claims and not precluded by prior art are included in this invention.
An area-rug cleaning method has steps of air spray ( 1 ) for removing dry-extractible dirt with angularly directed air pressure; immersion shampoo ( 9 ) for removing immersion-extractible dirt with immersion-shampooing that does not molest rug fibers; scrub wash ( 16 ) for removing adhered dirt such as stains, odors and urine with rotational scrub washing; vacuum extract ( 18 ) for removing wash fluid with dry vacuum extraction; water rinse ( 20 ); cool dry ( 23 ); dry clean ( 24 ) for removing wash-resistant dirt; acid condition ( 25 ) for neutralizing base cleaning agents with an acid-based catalyst; and pad rub ( 26 ) for rubbing nap of the area rugs with a cloth pad to provide a shine finish.
3
FIELD OF THE INVENTION This invention relates to the field of measurement of the quantity of particulate matter contained in a stack or flue gas stream. More particularly, the invention relates to improvements in the accuracy of methods presently used according to Environmental Protection Agency specifications to measure particulates in stack gas. BACKGROUND OF THE INVENTION As part of the continuing effort to improve the environmental quality, the Environmental Protection Agency has set certain standards for the quantity of particulates which can be emitted to the air from various industrial processes. The EPA has similarly specified the way in which compliance with their standards is to be measured. One such test for particulates is performed by weighing a filter paper of predetermined size, inserting it into a stack gas stream for a predetermined period and weighing it afterwards and calculating from the difference and the relative area of the filter and stack the total number of pounds of particulates emitted per hour. There are several difficulties with the EPA test as presently defined. One is that the stack gas stream typically contains materials such as H 2 S0 4 which are gaseous S0 3 at higher temperatures, e.g., above about 400° F., but tend to react with water vapor and to condense as acid when the stack gas temperature is below the dew point, which varies between about 225° and 400° F. depending on the concentration. Present EPA tests specify the temperature of the stack gas at which the sample is to be taken as being well below the dew point. Hence, liquified H 2 S0 4 tends to collect on the filter, interfering with measurements of the particulates, which are of different compositions. The test could therefore be improved as to accuracy by performing it in a region of the stack where the gases are well above the dew point, allowing the S0 3 gases to pass through the filter, and not interfering with the accuracy of the measurement. A second difficulty in the measurement of particulates in stack gas streams is that the filters, even when of very high quality quartz or borosilicate glass fiber filter materials, contain certain metallic impurities which tend to react with some of the components of the gas stream. Hence, some chemical species which would otherwise pass through the filter instead are attracted to the filter for chemical reaction and are bound up, thus again increasing the weight of the filter to a value higher than that which it would have had had only particulates physically trapped in the mesh of the filter been captured. OBJECTS OF THE INVENTION It is therefore an object of the invention to provide an improved method of measuring the amount of particulates in a flue gas stream. A further object of the invention is to provide a method whereby only particulates physically entrapped within the fibers of the filter are captured for weighing. Still another object of the invention is to provide a method for avoiding the capture of non-particulate matter on filter papers by chemical action. SUMMARY OF THE INVENTION The above needs of the art and objects of the invention are satisfied by the present invention according to which filter papers used for capturing particulates in flue gas streams containing S0 3 ions and the like are pretreated prior to use, in particular prior to weighing to establish a tare weight, by treatment with e.g., sulfuric acid whereby the metallic elements present in the filter material are prereacted so that no free sites for reaction with chemical elements contained in the flue gas stream remain present. BRIEF DESCRIPTION OF THE DRAWINGS The invention will be better understood if reference is made to the accompanying drawings in which: FIG. 1 shows an overall view of a system for refinement of crude oil comprising means for regeneration and recovery of catalysts used in the "cracking" of heavy hydrocarbons to lighter components in which the present invention plays an important part; and FIG. 2 is a schematic drawing showing the manner in which the filter may be conveniently inserted into and removed from the flue gas stack. DESCRIPTION OF THE PREFERRED EMBODIMENTS As noted above, the present invention relates to improved accuracy of measurement of particulates in flue gas streams. It will be appreciated that this invention will have applicability in many sorts of systems wherein a filter or other desirably inert structure tends to react with a substance which must be accurately measured. The broad concept of the invention, i.e., prereacting all possible impurities in the filter or other inert member to render it truly inert thus has wide utility. The present invention was made, however, in the course of developing better test methods for measurement of particulate emissions from catalyst recovery systems in oil refining operations and it is with respect to this application of the invention that its preferred embodiment will now be described. The broad overview of a petroleum refining plant is shown in FIG. 1. Gas is supplied to the base of the reactor unit 10, which is characterized as a fluidized catalytic cracking unit using zeolitic cracking catalysts. Such units are well-known and their details do not relate to the present invention. The cracked products are passed to a conventional main fractionating column 11 where they are separated into the various constituent parts as listed. The zeolitic catalysts used in cracking the gas are then regenerated in a regenerator 12. In the catalytic regenerator 12, coke is burned off the talcum powder-like catalyst in order to rejuvenate the catalyst. There are three devices which prevent the emission of the catalyst particles entrained in the hot exhaust system to the atmosphere. These devices are an inertial separator 14, a two-stage cyclone system indicated generally at 16 and an electrostatic precipitator 20. The coked catalyst particles enter the regenerator 12 in a combustion section. In this section the coke-laden catalyst is contacted concurrently with air supplied at the bottom of the regenerator, and the coke is burned to C0 2 , CO and H 2 0. The mixture of the now rejuvenated catalytic particles in the flue gas leaves the combustor section at about 4 ft/sec. Without control apparatus, this total amount of catalyst particles in the size range between zero and 100 microns would enter the atmosphere as particulates. The amount of potential emissions has been calculated for data collected in a particular example of such a system on Apr. 21, 1981; on that day, the total potential particulate emissions were 2,711,449 lbs/hr. The flue gas plus entrained particles travel up the regenerator at a velocity of about 2.5 ft/sec to the next control apparatus, the two-stage cyclone separator system 16. The mixture is accelerated to approximately 70 ft/sec as it enters the first stage of cyclone separation. Heavier particles are thrown to the wall by means of centrifugal force and after disengagment from the flue gas, fall by gravity down to the regenerator bed. The finer particles plus the flue gas pass out the top of the cyclone and into the second stage cyclone separator. Here smaller particles are similarly disengaged. At this point, the flue gas stream contains approximately 200 lbs/hr. of catalyst fines. The two-stage cyclone separator 16 has an overall efficiency of 99.95%, with the first stage 99.0% efficient and the second stage 98.5% efficient. The flue gas plus particles next enters the electrostatic precipitator 20. Here the particles are charged in an electric field and are attracted to an oppositely charged electrode where they are held until they are dislodged by mechanically "rapping" the cells. The gas stream leaving the electrostatic precipitator 20 contains 6 lbs/hr. of solid particulate matter. The individual efficiency of the electrostatic precipitator is thus 97%. The overall efficiency of the system including the inertial separator, the two-stage cyclone system and the electrostatic precipitator is 99.9998% reducing the potential particulate emissions of some 2,700,000 lbs/hr. to 6 lbs/hr. actual emissions. It is this last figure of 6 lbs/hr which must be met by the stack gas output from the refinery. Clearly accuracy of measurement is very important in a system where the overall efficiency need vary only slightly to greatly change the results of the test. In the presently defined EPA test, a filter of a corrosion and heat resistant material such as quartz, titanium or borosilicate glass fiber, perhaps with a paper backing is exposed to the flue gas in the stack 22. A schematic diagram of how this might be accomplished is shown in FIG. 2. The filter 24 is carried within a typically circular holder 26, which is inserted through an orifice in the wall 28 of the stack 22. The filter paper may be 5.5 cm in diameter when used with a 71/2 ft. diameter stack. Typically 40 cu. ft. of stack gas will pass through the filter in about an hour, out of roughly 70,000 total cu. ft. released. A suitable filter is sold by the Whatman Ltd. Company of England under Model No. 934-AH. Other EPA-approved methods will more typically be used; for example, the filter can be carried in a box external to the stack, as well understood by those skilled in the art. Suitable equipment for the purpose is sold by Joy Manufacturing Co., under the trade name "Emission Parameter Analyzer". However, as discussed above, even a high quality filter paper contains some metallic impurities which can react with chemicals in the stack gas which would otherwise pass therethrough, thus adding an erroneous additional weight to the filter which will show up in the weighing of the filter and provide a misleading result to the testing. Table 1 below shows typical filter papers of the quartz, titania and borosilicate types analyzed for the presence of metals which can form sulfates with, e.g., S0 3 in the stack gas stream. TABLE 1______________________________________Compositions of Filter Papers(Only Extractable Metals Which Can Form Sulfates)Metal Quartz Titania Borosilicate______________________________________Aluminum 0.24% 5.5% 2.5%Barium 0.016% 0.063% 0.023%Calcium 0.35% 8.5% 4.0%Potassium 0.068% .04% 0.5%Magnesium 0.13% 1.6% 1.5%Sodium 0.7% 1.0% 9.0%Zinc 0.012% 0.024% 0.0045%______________________________________ As discussed above, the present inventors have found that in order that the trace metals present in the filter paper are prevented from reacting with the S0 3 /H 2 S0 4 in the flue gas, it is desirable to pretreat the papers thus tying up the alkaline sites and trace metals in the paper and reducing its reactability to S0 3 /H 2 S0 4 so as to give more accurate stack testing results. In particular, simply exposing the filter papers to sulfuric acid for a period of on the order of an hour by soaking them, is sufficient to prereact these alkaline sites and trace metals. When the paper is thereafter dried, weighed to establish a tare weight, exposed to the flue gas, dried to eliminate any water and condensed H 2 S0 4 , and reweighed to establish an amount of particulates collected, the difference figure will not include any chemically bonded elements found in the flue gas. In particular, metal sulfates and their many hydrates (MS0 4 . nH 2 O) will no longer be formed during the testing process. It will be appreciated, of course, by those skilled in the art that the broad concept of the invention is to prereact the alkali metals and trace elements, and that it would not be necessary to use the same chemicals present in the process stream for prereaction; any other chemical which would prereact with the same components of the filter could be used thus rendering the filter chemically inert. While a preferred embodiment of the invention has been described, it should be appreciated that the method of the invention has broader applicability than that specifically described. In particular, the method of pretreating filters comprising trace elements which are reactive with components of a process stream can be applied to process streams not containing sulfates but containing other sorts of materials which would otherwise be bound up chemically to the filter papers, thus rendering the filtration operation more accurate. Moreover, of course, the invention has applicability to chemical processes far different from hydrocarbon refining operations as described above. Therefore, the above description of the invention should not be considered as a limitation on its scope, but merely as exemplary thereof; the scope of the invention is more properly defined by the following claims.
Method for measuring particulates in flue gas streams containing chemicals reactive with trace elements in the filters is disclosed which features pretreating the filters with chemicals comparable to those in the process stream whereby the reactions are completed prior to the measurement step, in particular, prior to establishment of the tare weight of said filter.
8
PRIOR APPLICATION This application is a division of Ser. No. 08/195,429 filed Feb. 14, 1994, now U.S. Pat. No. 5,531,063; which is a continuation-in-part of Ser. No. 08/022,207 filed Feb. 25, 1993 (abandoned) which is a continuation-in-part of Ser. No. 07/603,504 filed Oct. 26, 1990 (abandoned) and which is a continuation-in-part of Ser. No. 07/366,702 filed Jun. 15, 1989 now U.S. Pat. No. 4,976,096. FIELD OF THE INVENTION The present invention relates to the production of textile yarn and more specifically relates to the production of core/wrap yarn. PRIOR ART It is known that core/wrap yarn or wrapped core yarns may be produced by wrapping a fibrous sheath around a continuous filament core. Alternatively, a continuous filament may be wrapped around a staple fiber core. Still further, both the core and wrapping or sheathing may consist of staple fibrous materials, or both may be continuous filament materials. To date, in the production of ring-spun core/wrap yarn with staple fibrous materials, the wrapping step has been carried out prior to ring spinning, i.e., during the formation of roving from sliver, thereby producing a core/wrap roving, which subsequently must be spun into yarn in a ring spinning step; or during the drawing process, thereby producing a concentrically cored sliver, which subsequently must be roved into roving and spun into yarn in a ring spinning step. To date, no practical system has been developed to directly produce core/wrap yarn in a ring-spinning frame from a plurality of unwrapped roving strands. The following definitions apply to several terms that appear in the specification and claims: Carding--the use of a carding machine to align, clean, and straighten fibers, and to remove very short fibers as well as fine trash, to produce sliver. Drawing--the making parallel and straightening of sliver fibers to improve the uniformity of linear density, usually accomplished in 1, 2, or 3 passages through drawing equipment known as a draw frame or drafting frame. In each passage through a draw frame, several sliver strands are combined into a single sliver strand. Drafting--the process whereby a fiber bundle such as a sliver or roving is extended in length in order to reduce the linear density of the bundle and to increase the parallelization of the fibers. Various forms of drafting are employed in carding, drawing, roving, and ring-spinning. Sliver--the product produced by carding or drawing, i.e., a very coarse strand of fibers having essentially no twist. Roving process--conversion of sliver by drafting into a thinner strand called a roving in which a small amount of twist (normally 1-2 turns per inch) is imparted to the strand. This step is performed only in conjunction with subsequent ring spinning. No other type of spinning presently requires roving prior to spinning. Ring-spinning process--As used herein, an operation for converting roving into yarn by drafting a roving and imparting twist through use of a ring and a moving traveler on a ring-spinning frame. A small percentage of ring-spinning machines do not require prior formation of roving, but instead convert sliver directly into yarn except that the sliver is passed through additional drafting apparatus on the ring frame immediately prior to passage through the ordinary draft rolls/aprons associated with ring spinning. SUMMARY A new system is provided for producing a new product by directly producing core/wrap yarn from a plurality of unwrapped rovings. Broadly, the process comprises feeding a core strand and at least one separate wrap strand from the nip of a pair of draft rollers directly to a stationary strand support immediately downstream from the nip. The wrap strand(s) converge with the core strand in an open channel on the support means, and wrap around the core strand, so as to form core/wrap yarn. The product achieves a degree of wrap coverage never before attainable. Over 99% of the core is covered, i.e., less than 1% of the core is uncovered, whereas prior art core/wrap yarns achieve no better than 90% coverage, i.e., 10% of the core is uncovered. The support means provides an outwardly, downwardly curved support surface for the core and wrap strands. The curved surface includes an open channel which extends along the outwardly, downwardly curved support surface. The convergence and wrapping of the strands takes place in the channel. The wrapped yarn then is passed to an ordinary ring traveler and wind-up spindle of a ring-spinning assembly. In this manner, unwrapped roving is converted to core/wrap yarn in a continuous process. It is an object of the present invention to produce a new core/wrap yarn having the following advantages and distinctions over previous yarn products. It is practically is totally covered compared to much lesser covering percentage of previous core/wrap products. The core fibers are oriented along the length of the yarn and are positioned in the middle of the cross-section. Due to unique interlacing of the cover fibers (effected by two strands of drafted rovings, one on each side of the core material), the yarn sheath does not strip from the core at all. Furthermore, the strip resistance is equally good in both directions along the yarn. The staple-core/cotton-wrap yarn produced with a high tenacity staple fiber is significantly stronger than an equivalent 100% cotton yarn or an equivalent, regular intimate-blend yarn. The device is capable of producing relatively fine yarns (e.g., yarns of up to 40/1 cotton count or finer). Both the core as well as cover fibers contribute to the mechanical properties of the yarn produced by the present system; and mechanical properties, such as tear strength, tensile strength and abrasion resistance, of the fabrics produced from such yarns have exhibited significant improvements. The staple-core-spun yarns of the present invention are economical compared to existing filament-core yarns, mainly because of the lower cost of the staple fibers, compared to filament yarns. Inferior quality cotton, wool, manmade fiber, or any other fiber can be used in the core, and the premium fiber can be utilized in the cover to produce a premium-looking product. Many types of novelty yarns and fabrics, such as crepe-like, denim-like fabrics, and differential dye effects, can be produced by the spinning technique of the present invention. It is much easier to piece-up the ends during spinning, when compared to earlier reported spinning techniques. The staple-core yarns are highly useful for producing textile products where high strength and cotton surface are both desirable and/or critical, such as strong, easy-to-care-for and comfortable apparel of predominantly cotton, certain military fabrics, such as tentage, chambray shirting, work uniforms, strong sewing threads with heat-insulation cotton cover, and strong pill-resistant fabrics. Other objects and advantages of the present invention will be obvious from the following detailed description, in conjunction with the drawings in which: FIG. 1 is a perspective view of the overall system of the present invention. FIG. 2 is a partial perspective view of bar 20 of FIG. 1. FIG. 2a is an alternative embodiment of FIG. 1. FIG. 3 is a side view of part of the apparatus of FIG. 1. FIG. 3a is a side view of an alternative embodiment. FIG. 4 generally shows the use of bar 20 in conjunction with a plurality of side-by-side spinning systems mounted on the same frame. FIG. 5 is a photograph of a cross-section of the product of the present invention. FIG. 6 is a schematic of an apparatus for testing strip resistance of core/wrap yarns. FIG. 7 is a perspective view of a further embodiment of the present invention configured in an operational position. FIG. 8 is a perspective view of the further embodiment of the present invention configured in a second position for piecing-up. DETAILED DESCRIPTION Components of ordinary ring spinning equipment may be employed in the practice of the present invention. These are illustrated in FIG. 1 as rear draft rollers 1, drafting aprons 2, front draft rollers 3, pigtail guide 4, ring 5 and yarn bobbin 6. Hereinafter, this combination of elements is referred to as a single spinning system. In addition, there are three bobbins upstream of rear draft rollers 1. Two of these bobbins feed wrap roving 9 and 10 such as cotton roving to rear rollers 1, while the other bobbin feeds core roving 12 such as polyester roving thereto. Starting materials for the practice of the present invention, such as cotton and polyester rovings, may be prepared in a conventional manner. A conventional roving condenser 14 is disposed between the bobbins and rear rollers 1 in order to maintain a space between rovings. In addition, another condenser 15 is positioned between rollers 1 and aprons 2 so as to provide unconventional spacing between strands that emerge from the nip of front rollers 3. That is, this latter condenser is dimensioned to provide unequal spacing from the core strand to each wrap strand at the point of emergence of the strands from the nip of front rollers 3. In other words, the space between wrap strand 9 and core 12 is not the same as the space between wrap strand 10 and core 12 at the point of emergence of these strands from the nip of the front rollers 3. More specifically, the spacing between strand 9 and 12 is slightly less than the spacing between strands 10 and 12 in the case of a "Z" twist at yarn formation (FIG. 2), and vice-versa in the case of "S" twist (FIG. 2a). Generally, the lesser spacing is about 70-80% of the greater spacing between centerlines of respective strands. Referring to the lesser spacing between wrap and core, this will depend upon the fiber length being processed, and consequently on the size of the spinning equipment (i.e., short-, mid-, or long-staple spinning system). For a conventional cotton (short-staple) spinning system, the lesser space between wrap and core strands may be about 3/32" to 5/32". For long staple fibers such as wool, this dimension may vary from abut 1/4" to 5/8". Referring again to FIG. 1, disposed between pigtail guide 4 and front rollers 3 is a cylindrically-shaped, hollow or solid bar 20. The bar provides an outwardly, downwardly directed support surface for the core and wrap strands. The bar acts as a support for the strands and as the point at which wrapped yarn formation occurs. As can be seen in FIG. 2 or 2a, a groove 21 is present in bar 20 which constitutes the necessary open channel in the support surface through which the core strand passes, and in which the wrap strands envelop the core strand. Groove 21, which lies in a plane which is perpendicular to the plane of the front roller nip, is positioned such that core strand 12 passes directly from the nip into the groove, while wrap strands 9 and 10 first pass in contact with the surface of bar 20 adjacent groove 21 before entering the groove. Bar 20 and the wall of groove 21 most preferably are polished at least where these elements directly contact the wrap and core strands. The diameter of bar 20 depends upon fiber length, especially of the wrap fiber length. For a typical 1.5" long polyester-staple-core and 1" long cotton-wrap fibers, the diameter of the bar may be about 3/8" to 3/4". For a 3" long staple fiber, the bar may be as much as 2" in diameter. The fibrous strands emerging from the front roller nip are weak due to absence of twist. Only the inter-fiber cohesion and the support of bar 20 keep the materials intact and continuously flowing without breakage or interruption. The distance between bar 20 and the front roller nip should be such that there is essentially no drafting of the core strand between these two points. Thus, the distance between the yarn wrapping zone on bar 20 and the front roller nip, measured along the core strand, is less than the length of most of the fibers in the core strand. By avoiding drafting, the full yarn tension is maintained in the core strand upstream of bar 20. The loss of this tension otherwise would allow excessive "twist" upstream of bar 20 and would result in barber poling and less than subsequent full coverage of the core strand by the wrap strand. In addition, the distance of bar 20 from the front roller nip should be such that there is no drafting of the longest fibers (i.e., for cotton, the so-called "2.5% span length" fibers) in the wrap strands, but there is drafting of some of the shorter fibers therein. In other words, the distance along each wrap strand from the point of emergence of each wrap strand at the front roller nip to the yarn formation point on bar 20 is greater than the shortest fiber length therein but about 50-80% of the "staple" length. In the case of cotton-wrap fibers, the distance along the wrap strands measured from front roller nip to yarn formation typically is about 1/2" to 7/8". Thus, in the practice of the present invention, the fibers, after emerging from the nip of the front rollers, are loose with no twist to hold them together except for the slight twist imparted to the core-strand-fibers during passage from nip to bar. The bar acts as a guide for transportation of fibers from the nip to the yarn formation point on the bar. With further regard to positioning the bar, its longitudinal axis generally may be approximately equidistant from and parallel to the axes of the two front rollers, as shown in FIG. 3. The exact position should be set to provide the appropriate fiber path, as set forth above, from the nip of the front rolls to the point of contact with the bar, while still allowing clearance between the bar and each of the front rolls. The clearance between the bar and the top front roll should be sufficiently large that even the thickest segments of drafted strands cannot be gripped between these surfaces, which would otherwise have the undesirable effect that the lateral movements of the wrapper fibers would be restricted and the flow of fibers would be interrupted. The clearance between the bar and the bottom front roll should be sufficiently large so that the bar does not interfere with the scavenging of fibers by the spinning system's vacuum system in case of yarn breakage. The use of a bar having a half-circle rather than full circle cross-sectional shape permits the bar to be positioned closer to the nip and bottom roll, as shown in FIG. 3a. Taking the above factors into account, a typical spacing between the front roller nip and the closest surface of the bar is about 1/4" to 7/16" in the case of cotton/polyester wrap/core, and about 1" to 2" with regard to wool/polyester wrap/core. Referring again to FIG. 2 or 2a, groove 21 in bar 20 may be "v" shaped, rectangular, oval, circular, or any concave shape. Its width preferably should be slightly wider than the core strand diameter, i.e., about 11/2 to 2 times the core strand diameter. The depth of the groove is about the same as the width, preferably about 75-150% of the groove width, depending upon groove shape. A flat (rectangular) groove may have a depth less than the width, while a "v" shaped groove may have a maximum depth greater than its maximum width. Immediately after emergence from the front roller nip, the core and wrap strands tend to be flattened. However, the core strand tends to become cylindrical in cross-section as a result of being pulled into the groove 21 and as a result of some twist and tension being imparted thereto from downstream forces. These overall forces tend to condense and aggregate the core strand into a circular or oval cross-sectional shape. As the strands emerge from the nip they are merged into a so-called sandwich in groove 21 with the core strand in the middle. One wrap strand lies below the core strand, and the other wrap roving lies above the core strand in the wrapping zone, as illustrated in the alternative embodiments of FIGS. 2 and 2a. The two wrap strands thereafter spirally wind around the core strand. As shown in FIGS. 1-3, an "L" shaped yarn control guide 25, immediately downstream from and closely adjacent to bar 20, is screwed or otherwise attached to the bar. Guide 25 functions to prevent excessive yarn twist from flowing upstream past the guide. In addition, guide 25 stabilizes the zone of contact between the fibers and has 20. More specifically, as can be seen in FIG. 1a or 1b, the initial points of contact between the core strand and each of the two wrap strands do not coincide with one another. The wrap strand which initially contacts the core on the underside of the core ordinarily is the first contact point between strands, which is designated as point C in FIG. 3, while the other wrap strand "overwraps" at a second downstream contact point D. The art CD is the wrap zone. Prior to initial contact between any of the fibers, all three strands first should come into contact with the surface of the bar 20 along a common line upstream from point C, so that wrapping takes place on the bar 20, and not between the bar 20 and the front roller nip. This common line of contact, viewed on end as "A" in FIG. 3, is determined by the plane tangent to the upper roll of the front rollers 3 and the bar 20. Point B in FIG. 3 is the point of final contact of the wrapped yarn with the bar. This point is determined by the tangent from bar 20 to the surface of guide 25. Arc AB in FIG. 3 defines the zone of direct contact between the fibrous strands and the bar. In operation, the wrapping zone CD should be stable and finite, and within AB, despite normal fluctuations in the overall nature or the contact between the fibrous strands and bar 20 during the dynamics of the spinning operation. Otherwise, there will be less than maximum coverage of the core strand by the wrap strands. In this context, about 30°-90° of arc measured along the core strand should remain in contact with bar 20 during operation. Some factors which are taken into consideration in the positioning of guide 25 are as follows: As the pigtail guide 4 moves up and down with the ring rail 5 during winding of the product yarn, a positive deflection angle (FIG. 3, reference numeral 40) of the yarn from bar 20 around guide 25 to pigtail guide 4 (not shown in FIG. 3) should be maintained at all times. This deflection, however, should be as little as possible so as to avoid "trapping" too much twist, i.e., to avoid the situation where not enough twist flows upstream to maintain the integrity of the yarn or to perform the wrapping operation within the arc AB. This can be achieved by setting guide 25 so that it slightly deflects the path of the yarn from bar 20 to pigtail guide 4 when the pigtail and ring rail are at their lowest point in the package-building motion. For a typical cotton spinning frame a minimum deflection angle of about 10° to 15° is sufficient. The maximum deflection angle will occur when the pigtail guide and ring rail are at the maximum upward position, and typically will be about 9° greater than the initial (minimum) setting. A simple way to provide for positioning of guide 25 is to fixedly secure it to bar 20 as by means of screws, and to mount the ends of bar 20 on the spinning frame in such a manner as to provide for rotational adjustment of the bar about its own axis (i.e., the bar is screwed at its axis to a bracket which in turn is fixed to the frame of the spinning system). In this arrangement, whenever the position of the bar is changed by loosening its axial screws and rotating the bar, guide 25 likewise is repositioned in a clockwise or counterclockwise direction around the bar. During the spinning operation, if too much twist begins to flow back upstream so that, for instance, wrap zone CD migrates upstream of line A resulting in a barber-pole yarn, then the guide 25 can be repositioned (clockwise around bar 20 in FIG. 3) to increase the minimum deflection angle and thereby increase frictional drag, trap more twist, and re-adjust the position of the wrap zone back within arc AB on bar 20. This adjustment can be performed conveniently during the spinning operation, if the guide 25 is attached to the bar 20 as described above, by rotating the bar slightly while observing the wrap zone CD, so as to cause CD to center well within arc AB. It also is desirable to minimize the change in deflection as the pigtail guide moves. Thus, guide 25 should be as close to bar 20 as possible to minimize this variation. On the other hand, there should be sufficient clearance to permit easy piecing up. Generally, a distance of about 1/2" to 3/4", between guide 25 and bar 20 will be sufficient for both these purposes. In an alternative embodiment, guide 25 may be spring-loaded against the surface of bar 20 so as to lightly grip the yarn passing between bar and guide. In the preferred practice of the present invention, one continuous bar may accommodate several side-by-side spinning systems, as illustrated in FIG. 4, so that there is a single open channel or groove 21 adjacent each front roller pair in each of the spinning systems. The ends of the bar may be screwed into brackets 30 at the axis of the bar, which brackets in turn are secured to the overall frame 35 of the spinning systems. With regard to the operational speeds of the system of the present invention, spindle speed may be the same as that employed to spin yarn of a given linear density and twist multiple, in the ordinary manner, from a roving having the same overall blend composition and combined linear density as the three rovings (two wrapper plus core). In this case, the same twist gear and draft gear ratio would be used, and the same linear density yarn produced. The three rovings creeled per position in the present invention would each have to be prepared with linear densities, on the average, 1/3 of the linear density of the conventional roving. Alternatively, a separate approach would be to use three rovings, each having the same linear density as the comparable conventional single roving. In this case, however, the draft gear would be selected to increase the draft by a factor of three because three times as much roving (three rovings versus one roving) is pieced into the drafting zone. The same twist gear and spindle speed would produce the same yarn linear density and twist multiple as in the conventional single-roving case. A third approach combines a change in linear density of the rovings with a change in draft gearing. One combination would be to reduce the roving linear densities by a factor of two, and increase the draft by a factor of 1.5. For instance, if a 1-hank roving is normally used with a draft of 28 to produce Ne 28 yarn in the conventional way, then three 2-hank rovings (one core and two wrapper rovings of different composition) may be used with a draft of 42 to produce Ne 28 core/wrap yarn by the present invention. Once again, the spindle speed and twist gear ratio of the machine would be the same, as would the resultant twist multiple of the yarn produced. It will be obvious to those skilled in the art that many other practical combinations as to operational parameters exist. Variations in twist multiple, production rate, and yarn count may be accomplished by purely conventional manipulation of the textile relationships between the variables of roving linear density, spindle speed, twist and draft gearing, traveler weight, and so forth. In addition, basic ring spinning rules are to be considered. For instance, in cotton ring spinning, it is generally desirable to keep the draft below 50, and the roving count below three hank. The following are general spinning parameters for a 28-tex, 67% cotton/33% polyester-staple-core yarn produced by the system of the present invention: polyester roving (1)=2-hank (1.5"; 1.2 denier; and 6 g/denier cotton roving (2)=2-hank (11/16" staple; Acala) each; combined hank of roving=0.67 total draft=42 spindle speed (rpm)=9.100 twist multiple=4.00 traveller=#6 (1.6 grains) relative humidity=51 temperature (C)=20 The present invention may be employed to wrap fibrous materials around continuous filament core material such as continuous filament polyester, as well as around staple core material. When such continuous filament material is employed as the core strand, instead of being introduced into the drafting system through the back rolls, the filament core is fed into the drafting system immediately behind the front rollers and in alignment with groove 21 in bar 20. The operational speeds of the drafting zone and spindle are the same as for a similar system employing staple core material of the same linear density. The resulting product made from continuous polyester filament core strand and cotton wrap quite surprisingly has the same excellent strip resistance as core/wrap yarn having a staple core strand. The present invention is able to produce a degree of wrap or sheath coverage never before attainable in the prior art. In this regard, the prior art procedure is best exemplified by U.S. Pat. No. 4,541,231. Fabrics made from continuous filament core/wrap yarn produced by said prior art procedure and other prior art procedures exhibit "glittering", which means that the core color is "showing through", because there are a substantial number of uncovered-core spots. In comparison, a visual inspection of the yarn of the present invention, and fabrics made therefrom, exhibit no such "glittering," and the core essentially is totally covered by the sheath. Computer image analysis tests on random samples of continuous filament core/wrap yarns produced by the present invention and the best prior art, each sample having 10 centimeters of yarn, show that the yarn of the present invention provides over 99% sheath coverage (i.e., less than 1% of the core is uncovered or exposed), compared to no more than about 90% coverage or 10% exposed filament in the prior art. Thus, the present invention is able to provide less than 1/10 of the exposed filament attainable by the prior art. The type of coverage achieved by the present invention significantly reduces, and may essentially eliminate, sheath strippage ("skin-back") during subsequent processing, e.g., weaving, knitting, or handling of the yarn, thereby enhancing yarn processability and quality of end product. Another advantage achieved by the unusually high degree of sheath coverage is that, in the case of fiberglass continuous filament core/cotton wrap yarn, it significantly reduces fiber breakage (due to abrasion of exposed core material) and, consequently, shedding of the broken glass fragments. This helps to eliminate the problem of itching caused by the broken fragments and/or any broken individual filaments (in the exposed filament) in fabrics produced from prior art fiberglass continuous filament core/wrap yarns. Still another advantage of the present invention is that it provides a greater degree of color control and more suitability for chemical finishing for the finished fabric, because the unwanted presence of the continuous filament core on the yarn/fabric face, which most usually possesses a different degree of dyeability and chemical affinity or compatibility than the staple sheath, essentially is eliminated from the final fabric product. Also, the practically perfect core coverage provided by the invention in some cases will permit only dyeing of the wrap or sheath component, thus giving a significant cost advantage over the prior art wherein efforts must be made to dye both sheath and core. In addition, the unusually high degree of sheath coverage achieved by the present invention can eliminate the type of snagging, pilling, or other similar defects occasionally caused by exposed or broken core filament. The core coverage achieved by the present invention also can provide significantly improved protection of the core from heat, in the case of sewing threads, protection from light in the case of light-sensitive core materials, and protection from electricity and chemical imbalance in the case of yarns used in special applications. FIG. 5 is a photograph of a cross-section of the product of the present invention, in which the continuous filament core is polyester (individual strands are white circles in cross-section), and the sheath or wrap is cotton (individual strands are "amoeba-like" or dark blotches in cross-section). The total coverage of the wrap is quite evident. The product of the present invention exhibits such total coverage in cross-section essentially throughout the full length of the yarn. The continuous filament core material used in the present invention ordinarily has an extension or elongation capacity of less than 20% without rupture, whether the material be fiberglass, polyester, polyethylene, nylon, and the like. If the core material is highly stretchable (elastomeric) such that it can be extended or elongated at least 60% without breakage, then it is very important that the core be wrapped while it is in a partially stretched state. For example, if a particular core material has a rupture point at about 250-300% or even 300-500% elongation or extension, it is important that the core be stretched to at least 100% elongation at the point of wrapping. There will be partial contraction of the core material after wrapping, but the wrapped product nonetheless will remain in a substantially stretched state, after wrapping, during the entire processing and/or usage of the yarn. In other words, the wrapping prevents the core from returning to its completely unstretched state even in the absence of external tension on the wrapped yarn. Thus, in the practice of the present invention, any core material that is able to be stretched to, for example, 60% elongation without rupture, will be wrapped while it is in a stretched condition, and will remain in a substantially stretched condition, e.g., 20% or more elongation, when in its intended wrapped state. As indicated above, the core/wrap product produced by the apparatus of the present invention possesses a strip resistance never before attainable with prior art core/wrap yarns. In the prior art, while it has been thought desirable to impart the desirable properties of staple fiber to stronger but less desirable continuous filament, strip-resistance of the resultant staple fiber wrap always has been a serious problem with the yarns. None of the prior art continuous filament core/staple fiber wrap yarns are strip resistant. Stripping and fuzz generation problems of the staple fiber wrap inherently occur during processing, e.g., winding, warping, knitting or weaving, of such prior art yarns. The continuous filament core/staple fiber wrap yarns of the present invention are able to withstand the intensity of the severe strip resistance test hereinafter described. None of the prior art yarns of comparable linear density of this type of yarn are able to do so. FIG. 6 illustrates the apparatus used in the test. The device is a Rothschild yarn friction tester that has been modified with a suitable knitting needle mounted in the path of the yarn. Reference numeral 100 designates yarn emanating from bobbin 102. The yarn passes around guide and tension device 104 to a second tension device 106, then to a tension sensor 108, through the eye of knitting needle 110, to a second tension sensor 112, to a take-up drum 114, and finally to a take-up reel 116. Speed of the yarn is controlled by a yarn speed device 120 that controls the speed of take-up drum 114. The angle X formed by the yarn entering and exiting the eye of the knitting needle is about 10°. The knitting needle may range in size from 18 gauge to 54 gauge, in order to simulate the type of knitting needles ordinarily used in yarn processing. The needle is held stationary by means of a clamping device 122. The device is operated at a speed and tension to simulate the speed, tension and abrasion typically encountered in yarn processing such as knitting or weaving. The yarns of the present invention are able to be passed through this machine at a speed of 300 meters per minute, at a tension of 0.5 grams per den (denier) linear density, and yet not exhibit any stripping or fuzz formation. In addition, despite the abrasion, the core of the resultant yarn remains essentially completely covered, i.e., over 99% staple fiber coverage, and thereby there are no "bare spots" of core. On the other hand, a polyester-core/cotton-wrap yarn, 265 denier linear density, produced in the conventional way (e.g., by the apparatus of the present invention absent elements 20 and 25, while employing a single wrap roving), exhibited much minor stripping of the staple fiber wrap resulting in a fuzzy appearance after passing through the apparatus of FIG. 6 at the same operating conditions as above. In another test, fiberglass-core/cotton-wrap yarn, 265 denier, produced conventionally, exhibited a major strip on the staple fiber wrap resulting in yarn breakage, and many minor strips resulting in a fuzzy appearance after passing through the machine of FIG. 6 at speed of 200 meters per minutes and tension of 60 grams. In still another test, fiberglass-core/cotton-wrap yarn, 265 denier, produced conventionally, exhibited many minor strips of the staple fiber wrap resulting in a fuzzy appearance after passing through the machine of FIG. 6 at a speed of 120 meters per minute and tension of 40 grams. In both latter tests, the stripping was severe enough to cause difficulty in mechanical processing and to produce an inferior, unsatisfactory product. The following yarn linear densities and corresponding knitting needle sizes illustrate the densities of core/staple fiber wrap yarns of the present invention that are able to be tested with such needles as part of the above described test (FIG. 6), without causing strips or fuzz formation on the yarn, and without causing visible (to the naked eye) spots of core material to appear on the yarn: 1500-500 den yarn, 18-gage needle; 1000-300 den, 24-gage needle; 850-250 den, 36-gage needle; 550-150 den, 46-gage needle; 400-100 den, 54-gage needle. No prior art core/staple fiber wrap yarns of the same linear densities and corresponding needle sizes are able to survive such a test without causing strips or fuzz formation. In other words, referring for example to the linear density range 1500-500 den: any prior art core/wrap yarns having such a linear density will have noticeable strips and fuzz if tested with an 18-gage needle at the parameters set forth above. In addition, the test usually will create discernible visible spots of core material on the prior are yarn. A further embodiment of the present invention is shown in FIGS. 7 and 8. In the system according to this embodiment, an end portion 138 of the bar 220 is mounted to a first end of a bar 140 and the other end of the bar 220 includes a conical tip 142. The bar 220 is tapered so that the diameter of the portion 138 of the bar 220 is greater than the diameter of a portion 146 of the bar 220 which is adjacent to the groove 21. The tapered portion 146 is preferably 1/4 of an inch to 1/16 of an inch wide. In addition, the diameter of a portion 144 of the bar 220 which is adjacent to the conical tip 142 is greater than the diameter of the portion 146 of the bar 220. The diameter of the portions 138 and 144 of the bar 220 are preferably at least 1/4 inch greater than the diameter of the portion 146 of the bar 220. Those skilled in the art will recognize that the cross-section of the bar 220 of this embodiment may also be semi-circular in order to achieve the proper clearance between the bar 220 and the draft rollers 3. The yarn control guide 25 is movably coupled within a slot 152 formed in an intermediate portion of the bar 140 by means of a pin 154 and a second end of the bar 140 is rotatably coupled to a frame 148 of the spinning machine via a bolt 150. Thus the yarn guide 25 may be rotated about the bar 20 by moving the pin 154 within the slot 152. The operative position of the bar 140 as shown in FIG. 7 and, consequently, the operative position of the bar 20 and yarn guide 25, is limited by a stop pin 156 which projects from the frame 148 and prevents rotation of the bar 140 beyond the desired operative position. A spring 160 coupled between the bar 140 and the frame 148, is biased to maintain the bar 140 in the operative position abutting the stop pin 156. In the operative position, the bar 220 and the yarn guide 25 are preferably positioned as described in regard to the previous embodiments. The yarn guide 25 may be moved within the slot 152 so that a desired angular orientation, with respect to the bar 220, may be obtained. In operation, the spinning machine according to this embodiment functions substantially similarly to the spinning machines of the previously described embodiments except that, as the wrap roving 9 and 10 and the core roving 12 leave the front draft rollers 3, they contact the bar 220 along the tapered surface and are drawn into the groove 21. The spinning machine according to this embodiment also improves the piecing-up operation. When the yarn breaks, the operator swings the bar 140 and, consequently, the bar 220 and the yarn guide 25 out of the operative position into the piecing-up position shown in FIG. 8. Those skilled in the art will understand that the apparatus can include any known means for locking the bar 140 in the piecing-up position while the piecing-up operation is performed. This allows the operator to perform a "conventional" piecing-up operation. Specifically, while the bar 140 is in the piecing-up position and the bar 220 and the yarn guide 25 are out of the vicinity of the forward rollers 3, the piecing-up operation may be carried out in front of the rollers allowing a fiber overlap of 1/4 inch or less. When the piecing-up operation is complete, the operator removes the bar 140 from the piecing-up position and allows the bias of the spring 160 to it to return it to the operative position. As the bar 20 approaches the yarn, the conical tip 142 moves beneath the yarn and the yarn slides across the surface of the conical tip 142 and down the tapered surface of the bar 220 into the groove 21. Those skilled in the art will recognize that any properly angled surface will allow the forward end of the bar 220 to pass beneath the yarn so that the yarn is smoothly guided to the groove 21 and that this tip need not be conical. In contrast, the proximity of the bar 220 to the forward roller in the previous embodiments required the operator to piece-up by feeding the yarn from behind the forward rollers. This technique results in a fiber overlap of 2 inches or more and is slightly more time consuming than the "conventional" operation. Those skilled in the art will understood that the geometry of the groove 21 may be configured in the system according to this embodiment as described in regard to the previous embodiments. In addition, the bar 20 according to this embodiment may be longitudinally cut in half to form a semicircular cross-section as described in regard to the previous embodiments. Thus, in summary, prior art core/staple fiber wrap yarns of 1500-100 den are unable to pass the above test with such needles.
A method is provided for manufacturing a new core wrap yarn which is strip resistant to the degree that it is able to be passed through a knitting needle at an entrance-exit angle of about 10°, at a tension of 100 grams and a speed of 100 meters per minute, without any apparent stripping or fuzz generation, wherein the method allows for convenient piecing-up operations.
3
FIELD OF THE INVENTION The present invention relates to a chemically bonding material that forms a thin coating film on a surface of glass, plastic, metal or the like and to a method for manufacturing the same. BACKGROUND OF THE INVENTION It is well known to process the surface of a substrate such as glass by using silane-based, germanium-based, tin-based, titanium-based or zirconium-based molecules, for example, in the case of manufacturing a glass fiber reinforced plastic (FRP) by improving the adhesiveness between the glass fibers and the plastics. The conventional methods will be explained employing examples using silane-based molecules as follows. The conventional methods using germanium-based, tin-based, titanium-based or zirconium-based molecules may use the same method as in the example using silane-based molecules explained below. Silane-based molecules used in a first conventional example are chlorosilane-based molecules. Other halosilane molecules such as bromine silane-based molecules or the like have the same functions as chlorosilane-based molecules. A solution is prepared by dissolving in alcohol silane-based molecules having monochlorosilane groups, dichlorosilane groups or trichlorosilane groups as a material for forming a coating film. A method of dipping a substrate into the solution, a method of applying the solution to a substrate, a method of spraying the solution on a substrate or the like is used as a method for forming a coating film on a substrate using the solution. A coating film made up of chlorosilane-based molecules is formed using any one of such methods, although there are differences in thickness and in uniformity of the film in each method. Next, a second conventional example will be explained as follows. Molecules used here are alkoxysilane-based molecules. Isocyanate-based molecules have the same functions as the alkoxysilane-based molecules. A solution is prepared by dissolving silane-based molecules having monoalkoxysilane groups, dialkoxysilane groups or trialkoxysilane groups as a material for forming a coating film in hydrocarbon molecules. A method of dipping a substrate into the solution, a method of applying the solution to a substrate, a method of spraying the solution on a substrate or the like is used as a method for forming a coating film on a substrate using the solution. A coating film made up of alkoxysilane-based molecules is formed using any one of such methods, although there are differences in thickness and in uniformity of the film in each method. Then, the substrate on which a film has been formed is fired, wherein a temperature of 100° C. and a time period of one hour usually are employed as standard conditions. As a result, a siloxane bond is formed by a dehydration reaction, a dealcoholization reaction or the like between alkoxy groups of the alkoxysilane-based molecules and hydroxyl groups of the alkoxysilane-based molecules already hydrolyzed, between alkoxy groups of the alkoxysilane-based molecules, between hydroxyl groups of the alkoxysilane-based molecules already hydrolyzed, between hydroxyl groups on the surface of the substrate and alkoxy groups of the alkoxysilane-based molecules, or between hydroxyl groups on the surface of the substrate and hydroxyl groups of the alkoxysilane-based molecules already hydrolyzed, thus forming a coating film. As a third conventional example, a solution is prepared by dissolving chlorosilane-based molecules in a silicone oil. The solution prepared here is applied to a substrate by using the same method as in the first example, and thus forming a coating film. However, in the case of using the method for forming a coating film in the first conventional example mentioned above, the chlorosilane groups of the chlorosilane-based molecules react with the alcohol in which the chlorosilane groups dissolve, and alkoxysilane groups are formed. The alkoxysilane groups are changed to silane groups having high reactivity, and the chlorosilane-based molecules, alkoxy-based molecules changed from the chlorosilane-based molecules, silanol-based molecules changed further from the alkoxy-based molecules and the like react with each other. As a result, a thick coating film having a non-uniform thickness is formed. Furthermore, a tight chemically bonded film should be inherently formed by the reaction between hydroxyl groups on the surface of the substrate such as glass or the like and the chlorosilane groups or the alkoxy groups. However, the film formed here is not tightly bonded to the substrate, since the number of reactive chlorosilane groups, alkoxysilane groups and silanol groups which are included in the material molecules is overwhelmingly more than the number of the hydroxyl groups exposed on the surface of the substrate, and the great majority of the molecules therefore react with each other. Similarly, in the second conventional example, a coating film similar to that of the first conventional example is formed, since a reaction occurs between the alkoxysilane-based molecules and the silanol-based molecules changed from the alkoxysilane-based molecules. In the third conventional example, the chlorosilane-based molecules are not changed to silanol-based molecules, since the solution is composed of silicone oil and oils, which does not include water. However, the atmosphere in the dissolving process is not a dry atmosphere, so that a little water content comes to be included during the dissolving process. The water molecules are changed to silanol-based molecules by reacting gradually with the chlorosilane-based molecules, thus forming an oligomer. As a result, as a storage time of the material becomes longer, a coating film formed becomes similar to that of the first and second conventional examples. In the first, second and third conventional examples, the atmosphere is not controlled so as to be a dry atmosphere during the production of a chemically bonding material, the preparation of the material into a coating solution composition and the storage of the composition. Therefore, the method according to the first, second and third conventional examples mentioned above is disadvantageous in that the silane-based molecules are deactivated and do not react with the surface of a substrate such as glass or the like. SUMMARY OF THE INVENTION In order to solve the problems mentioned above in the prior art, it is an object of the present invention to provide a method improved so as to enable a chemically bonding material for forming a thin coating film whose thickness is less than a micrometer and is uniform to be produced without being deactivated, to be prepared into a coating solution composition and to be stored. A method for manufacturing a chemically bonding material and a chemically bonding material according to the present invention are characterized in that a compound expressed by the following general formula 1 (Formula 1), wherein A shows a group including carbon, B indicates Si, Ge, Sn, Ti or Zr, X is a hydrolyzable group and n indicates 1, 2 or 3, and at least one kind of compound not including active hydrogen groups are mixed, kneaded or dissolved in a dry atmosphere having a water vapor density of 0.0076 kg/m 3 or less. (Formula 1) ABX.sub.n In manufacturing a chemically bonding material composed of molecules expressed by Formula 1 and at least two kinds of molecules not including active hydrogen groups, the at least two kinds of molecules not including active hydrogen groups are pre-mixed, pre-kneaded or pre-dissolved in an atmosphere having a water vapor density of 0.011 kg/m 3 or less. Then, a mixture, a kneaded material or a dissolved material composed of at least the two kinds of molecules not including active hydrogen groups and the molecules expressed by Formula 1 is prepared by, for example, mixing, kneading or dissolving in an atmosphere having a water vapor density of 0.0076 kg/m 3 or less, In the situation mentioned above, the molecules not including active hydrogen groups are preferably non proton-based molecules, hydrocarbon molecules, siloxane molecules, carbon tetrachloride, chloroform or dichloroethane. The molecules not including active hydrogen groups are preferably stored in an atmosphere having a water vapor density of 0.0076 kg/m 3 or less before being mixed with, kneaded with or dissolved in the molecules expressed by Formula 1 in an atmosphere having a water vapor density of 0.0076 kg/m 3 or less. Furthermore, the molecules expressed by Formula 1 are preferably stored in an atmosphere having a water vapor density of 0.0076 kg/m 3 or less before being mixed with, kneaded with or dissolved in the molecules not including active hydrogen groups in an atmosphere having a water vapor density of 0.0076 kg/m 3 or less. Materials further added other than the molecules expressed by Formula 1 and the molecules not including active hydrogen groups which are included in the chemically bonding material are also preferably stored in an atmosphere having a water vapor density of 0.0076 kg/m 3 or less before being mixed, kneaded or dissolved in an atmosphere having a water vapor density of 0.0076 kg/m 3 or less. Moreover, the material further added is preferably an inorganic substance, an inorganic oxide or a mineral salt. The material further added may be any one of, for example, a silica gel, calcium sulfate anhydride, calcium oxide, magnesium oxide or the like, which is generally used for a desiccating agent or a dehumidifying agent. DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be explained in more detail as follows. According to the present invention, in the process of mixing, kneading or dissolving at least molecules expressed by Formula 1 and molecules not including active hydrogen groups, the water content included in the material that has been mixed, kneaded or dissolved can be restrained by controlling the water vapor density, based on the measurement by a hygrometer, so as to be 0.0076 kg/m 3 or less. As a result, the performance of a coating film manufactured using the material can be maintained. The molecules expressed by Formula 1 and the molecules not including active hydrogen groups both are preferably stored in an atmosphere having a water vapor density of 0.0076 kg/m 3 or less before being mixed, kneaded or dissolved together. When there are molecules added other than the two kinds of molecules mentioned above, the molecules added are preferably stored also in an atmosphere having a water vapor density of 0.0076 kg/m 3 or less. Furthermore, in measuring humidity using a hygrometer, the lower limit of humidity cannot be provided, since the lower limit is changed according to the storage condition (high temperature storage, low temperature storage) and the length of the storage time of the chemically bonding material of the present invention. Generally, a material constitution that is endurable against high temperature storage and long term storage can be obtained as the value of the humidity measured using a hygrometer approaches 0%. However, in the case of preparing a chemically bonding material in an atmosphere having a water vapor density over 0.0076 kg/m 3 , the material deteriorates between the time when the material is manufactured and the time when the material is actually used by a user, excepting the case of use right after the preparation of the material, since the reaction between the materials is accelerated. According to the present invention, a molecular film having a thickness in the range from about 0.1 nm to about 1 μm can be formed on a substrate by forming siloxane bonds between the substrate and silane-based compounds. It is preferable that the silane-based compound be a compound comprising an alkyl group or a fluoroalkyl group. A specific example of the compound comprising a fluoroalkyl group includes a fluoroalkylsilane compound expressed by a general formula C n F 2n+1 (CH 2 ) 2 SiCl 3 (n=a positive integer of 1 to 30), such as heptadecafluoro1,1,2,2,tetrahydrodecyltrichlorosilane or the like. As a solvent for dissolving the chlorosilane-based compound, any solvent can be used, as long as it does not contain active hydrogen atoms that react with the chlorosilane-based compound. For example, a hydrocarbon-based solvent, a hydrocarbon halide-based solvent, an alkylsiloxane-based solvent, or a silicone oil-based solvent can be used for the fluoroalkylsilane compound. Specific examples of the hydrocarbon-based solvent include a solvent of oils expressed by a general formula C n H 2n+2 (n=a positive integer) such as a turpentine oil or the like, or expressed by a general formula C n H 2n . Specific examples of the hydrocarbon halide-based solvent include a solvent expressed by a general formula C n H 2n-m+2 X m (n=a positive integer, m=a positive integer, and X=halogen) such as octadecafluorooctane or the like. Specific examples of the alkylsiloxane-based solvent include a linear silicone solvent expressed by a general formula R 1 (R 2 R 3 SiO) n R 4 (n=a positive integer, R 1 , R 2 , R 3 , and R 4 =alkyl groups) such as hexamethyldisiloxane or the like, or a cyclic silicone solvent expressed by a general formula (R 1 R 2 SiO) n (n=a positive integer, R 1 and R 2 =alkyl groups) such as octamethylsiloxane, or a mixture thereof. Examples of a chemically bonding material that can be used in the present invention are listed below: CH.sub.3 (CH.sub.2).sub.r SiX.sub.p Cl.sub.3-p ( 1) CH.sub.3 (CH.sub.2).sub.s O(CH.sub.2).sub.t SiX.sub.p Cl.sub.3-p ( 2) CH.sub.3 (CH.sub.2).sub.u --Si(CH.sub.3).sub.2 (CH.sub.2).sub.v --SiX.sub.p Cl.sub.3-p ( 3) CF.sub.3 COO(CH.sub.2).sub.w SiX.sub.p Cl.sub.3-p ( 4) (where p is an integer of 0 to 2, r is an integer of 1 to 25, s is an integer of 0 to 12, t is an integer of 1 to 20, u is an integer of 0 to 12, v is an integer of 1 to 20, and w is an integer of 1 to 25. X is hydrogen, an alkyl group, an alkoxyl group, a fluorine containing alkyl group, or a fluorine containing alkoxyl group.) Furthermore, specific examples of the bonding material are the following compounds: CH.sub.3 CH.sub.2 O(CH.sub.2).sub.15 SiCl.sub.3 ( 5) CH.sub.3 (CH.sub.2).sub.2 Si(CH.sub.3).sub.2 (CH.sub.2).sub.15 SiCl.sub.3 ( 6) CH.sub.3 (CH.sub.2).sub.6 Si(CH.sub.3).sub.2 (CH.sub.2).sub.9 SiCl.sub.3 ( 7) CH.sub.3 COO(CH.sub.2).sub.15 SiCl.sub.3 ( 8) CF.sub.3 (CF.sub.2).sub.7 --(CH.sub.2).sub.2 --SiCl.sub.3 ( 9) CF.sub.3 (CF.sub.2).sub.5 --(CH.sub.2).sub.2 --SiCl.sub.3 ( 10) CF.sub.3 (CF.sub.2).sub.7 --C.sub.6 H.sub.4 --SiCl.sub.3 ( 11) Furthermore, instead of the chlorosilane-based chemically bonding material as described above, an isocyanate-based chemically bonding material obtained by substituting all of the chlorosilyl groups with isocyanate groups can be used. Examples thereof are as follows: CH.sub.3 --(CH.sub.2).sub.r SiX.sub.p (NCO).sub.3-p ( 12) CF.sub.3 --(CH.sub.2).sub.r SiX.sub.p (NCO).sub.3-p ( 13) CH.sub.3 (CH.sub.2).sub.s O(CH.sub.2).sub.t SiX.sub.p (NCO).sub.3-p ( 14) CH.sub.3 (CH.sub.2).sub.u --Si(CH.sub.3).sub.2 (CH.sub.2).sub.v --SiX.sub.p (NCO).sub.3-p ( 15) CF.sub.3 COO(CH.sub.2).sub.w SiX.sub.p (NCO).sub.3-p ( 16) (where, p, r, s, t, u, v, w and X are the same as above.) Instead of the above-mentioned bonding materials, the bonding material compounds specifically listed below can be used. CH.sub.3 CH.sub.2 O(CH.sub.2).sub.15 Si(NCO).sub.3 ( 17) CH.sub.3 (CH.sub.2).sub.2 Si(CH.sub.3).sub.2 (CH.sub.2).sub.15 Si(NCO).sub.3 ( 18) CH.sub.3 (CH.sub.2).sub.6 Si(CH.sub.3).sub.2 (CH.sub.2).sub.9 Si(NCO).sub.3 ( 19) CH.sub.3 COO(CH.sub.2).sub.15 Si(NCO).sub.3 ( 20) CF.sub.3 (CF.sub.2).sub.7 --(CH.sub.2).sub.2 --Si(NCO).sub.3 ( 21) CF.sub.3 (CF.sub.2).sub.5 --(CH.sub.2).sub.2 --Si(NCO).sub.3 ( 22) CF.sub.3 (CF.sub.2).sub.7 --C.sub.6 H.sub.4 --Si(NCO).sub.3 ( 23) Furthermore, as the chemically bonding material, in general, a substance expressed by a formula SiX k (OA) 4-k (X is the same as above, A is an alkyl group, and k is 0, 1, 2, or 3) can be used. In particular, when a substance expressed by CF 3 --(CF 2 ) n --(R) q --SiX p (OA) 3-p (n is a positive integer of 1 or more, preferably an integer of 1 to 22, R is an alkyl group, a vinyl group, an ethynyl group, an aryl group, silicon or substituent containing an oxygen atom, q is 0 or 1, and X, A, and p are the same as above) is used, a film having a more excellent antifouling property can be used. However, it is not limited thereto. Other examples are CH 3 --(C H 2 ) r --SiX p (OA) 3-p and CH 3 --(CH 2 ) s --O--(CH 2 ) t --SiX p (O A) 3-p , CH 3 --(CH 2 ) u --Si(CH 3 ) 2 --(CH 2 ) v --SiX p (OA) 3-p , C F 3 COO--(CH 2 ) w --SiX p (OA) 3-p (where, p, r, s, t, u, v, w, X and A are the same as above.) Furthermore, more specific examples of the chemically bonding material are as follows: CH.sub.3 CH.sub.2 O(CH.sub.2).sub.15 Si(OCH.sub.3).sub.3 ( 24) CF.sub.3 CH.sub.2 O(CH.sub.2).sub.15 Si(OCH.sub.3).sub.3 ( 25) CH.sub.3 (CH.sub.2).sub.2 Si(CH.sub.3).sub.2 (CH.sub.2).sub.15 Si(OCH.sub.3).sub.3 ( 26) CH.sub.3 (CH.sub.2).sub.6 Si(CH.sub.3).sub.2 (CH.sub.2).sub.9 Si(OCH.sub.3).sub.3 ( 27) CH.sub.3 COO(CH.sub.2).sub.15 Si(OCH.sub.3).sub.3 ( 28) CF.sub.3 (CF.sub.2).sub.5 (CH.sub.2).sub.2 Si(OCH.sub.3).sub.3 ( 29) CF.sub.3 (CF.sub.2).sub.7 --C.sub.6 H.sub.4 --Si(OCH.sub.3).sub.3 ( 30) CH.sub.3 CH.sub.2 O(CH.sub.2).sub.15 Si(OC.sub.2 H.sub.5).sub.3 ( 31) CH.sub.3 (CH.sub.2).sub.2 Si(CH.sub.3).sub.2 (CH.sub.2).sub.15 Si(OC.sub.2 H.sub.5).sub.3 ( 32) CH.sub.3 (CH.sub.2).sub.6 Si(CH.sub.3).sub.2 (CH.sub.2).sub.9 Si(OC.sub.2 H.sub.5).sub.3 ( 33) CF.sub.3 (CH.sub.2).sub.6 Si(CH.sub.3).sub.2 (CH.sub.2).sub.9 Si(OC.sub.2 H.sub.5).sub.3 ( 34) CH.sub.3 COO(CH.sub.2).sub.15 Si(OC.sub.2 H.sub.5).sub.3 ( 35) CF.sub.3 COO(CH.sub.2).sub.15 Si(OC.sub.2 H.sub.5).sub.3 ( 36) CF.sub.3 COO(CH.sub.2).sub.15 Si(OCH.sub.3).sub.3 ( 37) CF.sub.3 (CF.sub.2).sub.9 (CH.sub.2).sub.2 Si(OC.sub.2 H.sub.5).sub.3 ( 38) CF.sub.3 (CF.sub.2).sub.7 (CH.sub.2).sub.2 Si(OC.sub.2 H.sub.5).sub.3 ( 39) CF.sub.3 (CF.sub.2).sub.5 (CH.sub.2).sub.2 Si(OC.sub.2 H.sub.5).sub.3 ( 40) CF.sub.3 (CF.sub.2).sub.7 C.sub.6 H.sub.4 Si(OC.sub.2 H.sub.5).sub.3 ( 41) CF.sub.3 (CF.sub.2).sub.9 (CH.sub.2).sub.2 Si(OCH.sub.3).sub.3 ( 42) CF.sub.3 (CF.sub.2).sub.5 (CH.sub.2).sub.2 Si(OCH.sub.3).sub.3 ( 43) CF.sub.3 (CF.sub.2).sub.7 (CH.sub.2).sub.2 SiCH.sub.3 (OC.sub.2 H.sub.5).sub.2 ( 44) CF.sub.3 (CF.sub.2).sub.7 (CH.sub.2).sub.2 SiCH.sub.3 (OCH.sub.3).sub.2 ( 45) CF.sub.3 (CF.sub.2).sub.7 (CH.sub.2).sub.2 Si(CH.sub.3).sub.2 OC.sub.2 H.sub.5 ( 46) CF.sub.3 (CF.sub.2).sub.7 (CH.sub.2).sub.2 Si(CH.sub.3).sub.2 OCH.sub.3 ( 47) EXAMPLES A method of manufacturing a chemically bonding material according to the present invention and a chemically bonding material formed by using the same method will be explained in more detail as follows. However, the present invention is not limited to the examples mentioned below. Example 1 Using a constant humidity bath having a relative humidity based on the measurement by a hygrometer of 30% (a water vapor density of 0.0060 kg/m 3 ) and a temperature of 22° C., 8 g of 1,1,2,2-tetrahydroheptadecafluorooctyltrichlorosilane (C 8 F 17 (CH 2 ) 2 SiCl 3 ) as a chemically bonding material and 40 g of octamethyltetrasiloxane as a solvent were mixed by stirring in an Erlenmeyer flask for 15 minutes, thus preparing a solution. The solution was transferred to a vessel in the constant humidity bath, and then a square glass plate of 30 mm×30 mm was immediately dipped into the solution in the vessel for 30 minutes. As a next step, the solution was put into two glass tubes in the constant humidity bath, and each of the glass tubes was closed with a cover made of plastic. One of the two glass tubes was left in a constant temperature bath maintaining the temperature at 70° C. for five days and the other glass tube was left in a constant temperature bath maintaining the temperature at 100° C. for five days. Then, as in the operation mentioned above, a solution left in a constant humidity bath having a relative humidity of 30% (a water vapor density of 0.0060 kg/m 3 ) and a temperature of 22° C. was put into a vessel, and a square glass plate of 30 mm×30 mm was dipped into the solution for 30 minutes. A dehydrochlorination reaction occurred due to the presence of hydroxyl groups (--OH) on the surface of the glass plate. As a result, a coating film made of 1,1,2,2-tetrahydroheptadecafluorooctyltrichlorosilane was formed (Formula 2). Next, the glass plate was taken out from the solution and the solution remaining on the surface of the glass plate was blown away. When the glass plate was put in the air, hydrolysis and dehydration reactions proceeded as shown in the following Formulas 3 and 4 due to the reaction between water components in the air and the chlorosilane. A water droplet was dropped onto the surface of the three types of glass plates mentioned above, and the angle formed by the water droplet and the surface of the glass plate (a contact angle) was measured. The results are shown in Table 1. ##STR1## Example 2 In a constant temperature bath having a relative humidity based on the measurement by a hygrometer of 48% (a water vapor density of 0.0096 kg/m 3 ) and a temperature of 22° C., 20 g of a hydrocarbon mixture (for example, paraffin (manufactured by Wako Pure Chemical Industries, Ltd.) or paraffin wax (Aldrich Chemical Co. Ink.))having a fusing point at around 70° C. was put into a beaker. The hydrocarbon mixture was heated to 90° C. and melted. Then, 40 g of octamethyltetrasiloxane was further added therein and mixed by stirring for 30 minutes. The solution was transferred into a glove box having a relative humidity based on the measurement by a hygrometer of 5% or less (a water vapor density of 0.0010 kg/m 3 or less) (lower than the measuring limit by a hygrometer), and 8 g of 1,1,2,2-tetrahydroheptadecafluorooctyltrichlorosilane was added to the solution and dissolved by stirring for 15 minutes. This solution was put onto a cloth in the same glove box and was immediately applied to a square glass plate of 30 mm×30 mm. Then, extra solution remaining on the glass plate was wiped off with another cloth. As a result, a coating film made of 1,1,2,2-tetrahydroheptadecafluorooctyltrichlorosilane was formed on the surface of the glass plate. Next, the solution was put into two glass tubes in the same glove box mentioned above, and each of the glass tubes was closed with a cover made of plastic. One of the two glass tubes was left in a constant temperature bath maintaining the temperature at 70° C. for five days and another glass tube was left in a constant temperature bath maintaining the temperature at 100° C. for five days. After that, the solution was put onto a cloth and was applied to a glass plate. Then, extra solution remaining on the glass plate was wiped off with another cloth. As a result, a coating film made of 1,1,2,2-tetrahydroheptadecafluorooctyltrichlorosilane was formed on the surface of the glass plate. A water droplet was dropped onto the surface of the three types of glass plates mentioned above, and the contact angles were measured. The results are shown in Table 1. Comparative Example 1 In a constant humidity bath having a relative humidity based on the measurement by a hygrometer of 69% (a water vapor density of over 0.0137 kg/m 3 ), 8 g of 1,1,2,2-tetrahydroheptadecafluorooctyltrichlorosilane and 40 g of octamethyltetrasiloxane were mixed by stirring in an Erlenmeyer flask for 15 minutes, thus preparing a solution. The solution was transferred to a constant humidity bath having a relative humidity based on the measurement by a hygrometer of 5% or less (a water vapor density of 0.0010 kg/m 3 or less) and was put into a vessel. A square glass plate of 30 mm×30 mm was immediately dipped into the solution. As a result, a coating film made of 1,1,2,2-tetrahydroheptadecafluorooctyltrichlorosilane was formed on the surface of the glass plate. Next, the solution was put into two glass tubes in the same constant humidity bath having a relative humidity of 5% or less (a water vapor density of 0.0010 kg/m 3 or less), and each of the glass tube was closed with a cover made of plastic. One of the two glass tubes was left in a constant temperature bath maintaining the temperature at 70° C. for five days and another glass tube was left in a constant temperature bath maintaining the temperature at 100° C. for five days. After that, in the same constant humidity bath mentioned above having a relative humidity of 5% or less (a water vapor density of 0.0010 kg/m 3 or less), the solution was put into a vessel, and a square glass plate of 30 mm×30 mm was dipped into the solution for 30 minutes. As a result, a coating film made of 1,1,2,2-tetrahydroheptadecafluorooctyltrichlorosilane was formed on the surface of the glass plate. A water droplet was dropped onto the surface of the three types of glass plates mentioned above, and the contact angles were measured. The results are shown in Table 1. Comparative Example 2 In a constant temperature bath having a relative humidity based on the measurement by a hygrometer of 61% (a water vapor density of over 0.0121 kg/m 3 ), 20 g of a hydrocarbon mixture having a fusing point at around 70° C. was put into a beaker. The hydrocarbon mixture was heated to 90° C. and melted. Then, 40 g of octamethyltetrasiloxane was further added therein and mixed by stirring for 30 minutes. The solution was transferred into a glove box having a relative humidity based on the measurement by a hygrometer of 5% or less (a water vapor density of 0.0010 kg/m 3 or less) (lower than the measuring limit by a hygrometer), and 8 g of 1,1,2,2-tetrahydroheptadecafluorooctyltrichlorosilane was added futher to the solution and dissolved by stirring for 15 minutes. This solution was put onto a cloth in the same glove box and was immediately applied to a square glass plate of 30 mm×30 mm. Then, extra solution remaining on the glass plate was wiped off with another cloth. Next, the solution was put into two glass tubes in the same glove box having a relative humidity of 5% or less (a water vapor density of 0.0010 kg/m 3 or less), and each of the glass tubes was closed with a cover made of plastic. One of the two glass tubes was left in a constant temperature bath maintaining the temperature at 70° C. for five days and another glass tube was left in a constant temperature bath maintaining the temperature at 100° C. for five days. After that, the solution was put onto a cloth and was applied to a glass plate in the same glove box having a relative humidity of 5% or less (a water vapor density of 0.0010 kg/m 3 or less). Then, extra solution remaining on the glass plate was wiped off with another cloth. As a result, a coating film made of 1,1,2,2-tetrahydroheptadecafluorooctyltrichlorosilane was formed on the surface of the glass plate. A water droplet was dropped onto the surface of the three types of glass plates mentioned above, and the contact angles were measured. The results are shown in Table 1. TABLE 1______________________________________ Contact Angle (°) Right after After stored After stored Production at 70° C. at 100° C.______________________________________Example 1 111 110 112Example 2 108 108 108Comparative 79 64 52Example 1Comparative 109 92 80Example 2______________________________________ Example 3 In a material in which chlorosilane-based molecules and molecules not having active hydrogen groups are mixed in an environment having high humidity, a hydrogen chloride gas is generated by the reaction between the active hydrogen and the chlorosilane-based molecules that are included in the material. Then, a material in which fine powder of calcium carbonate as a third material was further kneaded with the material was prepared, wherein calcium chloride, carbon dioxide and water molecules were generated due to the reaction between the hydrogen chloride gas and calcium carbonate. The water molecules further react with unreacted chlorosilane-based molecules, so that a hydrogen chloride gas was newly generated. In the case not including active hydrogen groups, neither a hydrogen chloride gas nor carbon dioxide is generated. Therefore, the presence and the amount of the molecules having active hydrogen groups can be known by measuring the amount of carbon dioxide generated. Then, the material in which the three kinds of molecules mentioned above have been mixed was put into a hermetically sealed enclosure, and was stored in a constant temperature bath maintaining the temperature at 70° C. for 40 hours. After that, the amount of carbon dioxide in the hermetically sealed enclosure was measured. As a pre-kneading process, 4 g of hydrocarbon mixture having a fusing point at around 70° C. was put into a beaker. The solution was heated to 90° C. and dissolved. Then, 8 g of octamethyltetrasiloxane and 8 g of calcium carbonate were further added therein and the solution was kneaded by stirring for 30 minutes. The pre-kneading was carried out under two conditions, i.e. in a constant humidity bath having a relative humidity based on the measurement by a hygrometer of 40% (a water vapor density of 0.0080 kg/m 3 ) and in a constant humidity bath having a relative humidity based on the measurement by a hygrometer of 69% (a water vapor density of over 0.0137 kg/m 3 ). In addition, 1.5 g of 1,1,2,2-tetrahydroheptadecafluorooctyltrichlorosilane and the kneaded material mentioned above were mixed by stirring for 15 minutes. The step of mixing by stirring was carried out under two conditions, i.e. in a glove box having a relative humidity based on the measurement by a hygrometer of 5% or less (a water vapor density of 0.0010 kg/m 3 or less) (lower than the measuring limit by a hygrometer) and in a constant humidity bath having a relative humidity based on the measurement by a hygrometer of 69% (a water vapor density of over 0.0137 kg/m 3 ). The mixed material prepared by the steps mentioned above was put into a container in which a volume expansion can be measured, and was stored in a constant temperature bath having a temperature of 70° C. for 40 hours. After that, the amount of carbon dioxide was determined from the results of the density of the carbon dioxide measured by using a gas detecting tube and the degree of volume expansion in the container. The results are shown in Table 2. TABLE 2______________________________________Relative Humidity 40% 69% 40% 69%at Pre-kneadingRelative Humidity at mixing of <5% <5% 69% 69%Chlorosilane-based MoleculeAmount of Carbon Dioxide after ˜0 ml 0.2 ml 0.2 ml 0.4 mlStorage at 70° C.______________________________________ In the case where pre-mixing was carried out in an environment having a vapor density of 0.011 kg/m 3 or more, which condition was further worse than that of Comparative Example 2, and the pre-mixed molecules not having active hydrogen groups were mixed with chlorosilane-based molecules in an environment having a vapor density of 0.0076 kg/m 3 or more, the results obtained were further worth than the results of Comparative Examples 1 and 2. As shown in Table 1, in the case of mixing chlorosilane-based molecules and molecules not having active hydrogen groups in the environment having a vapor density of 0.0076 kg/m 3 or more, it can be found that the deterioration has proceeded compared to the time when the film was manufactured, since the contact angle is 80° or less, which should normally be about 110°. In the case of storing the mixture at a constant temperature, the deterioration further proceeds. In the case where the pre-kneading was carried out in an environment having a vapor density of 0.011 kg/m 3 or more, the pre-kneaded material was deteriorated after being stored at a high temperature, even if the mixing with chlorosilane-based molecules was carried out in an environment having a vapor density of 0.0076 kg/m 3 or less as a next step. The solution of Example 1 was transparent, but the solution of Comparative Example 1 was cloudy and a lot of white suspended matter was observed in the solution. The comparison of the state in Example 2 and in Comparative Example 2 by visual observations was not possible as in Example 1 and in Comparative Example 1, since a white hydrocarbon compound has been kneaded in Example 2 and in Comparative Example 2. As shown in Table 2, in the case where the pre-kneading was carried out in an environment having a vapor density of 0.011 kg/m 3 or more and in the case where the mixing of the chlorosilane-based molecules and the pre-kneaded material mentioned above was carried out in an environment having a vapor density of 0.0076 kg/m 3 or more, the most carbon dioxide was generated when both were handled under high humidity, and the generation of carbon dioxide was observed also when any one of them was handled under high humidity. However, the generation of carbon dioxide was not observed when the both manipulations were handled while controlling the humidity below a specified value. Thus, it was confirmed that controlling humidity is very important for the method for manufacturing the chemically bonding material and the chemically bonding material according to the present invention. Moreover, the same results can be obtained also using other halosilane-based molecules having high reactivity instead of using chlorosilane-based molecules. Since alkoxysilane-based molecules become silanol-based molecules having high reactivity due to the presence of water molecules, the reaction among molecules occurs, which hinder the formation of a coating film. Accordingly, the same results as in the Examples and in the Comparative Examples mentioned herein are obtained. The same results as mentioned above can be obtained also in the case of using germanium-based, tin-based, titanium-based or zirconium-based molecules, which have an equivalent activity to or more activity than silicon-based molecules. Furthermore, the state of forming a coating film in the Examples and in the Comparative Examples was judged by measuring the contact angles. The judgement enables the density of the tricarbonfluoride group and the exposure of dicarbonfluoride other than tricarbonfluoride, which is inferior in water repelling, to be detected by differences in the density and in the orientation of the molecules, since the tricarbonfluoride group of the chlorosilane-based molecules used is exposed on the surface of the coating film. Thus, the state of a coating film can be detected easily by measuring a contact angle. The results obtained herein can apply to chlorosilane-based molecules composed only of hydrocarbon groups not having carbonfluoride groups. As described above, the present invention enables a thin coating film having a high molecular density for forming a film and uniformity in thickness to be formed, which was not possible in a conventional technique, by the following steps: producing a chemically bonding material for forming a thin coating film whose thickness is less than a micrometer and is uniform without deactivating; preparing the material into a coating solution composition; and storing it. The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The embodiments disclosed in this application are to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are intended to be embraced therein.
A method for manufacturing a chemically bonding material comprising the steps of: mixing a compound expressed by a general formula ABX n (Formula 1), wherein A shows a group including carbon, B indicates Si, Ge, Sn, Ti or Zr, X is a hydrolyzable group and n indicates 1, 2 or 3, and at least one kind of compound not including active hydrogen groups in a dry atmosphere having a water vapor density of 0.0076 kg/m 3 or less; and storing the same in a dry atmosphere having a water vapor density of 0.0076 kg/m 3 or less. A coating solution including compounds that are easily hydrolyzed is stored in a dry state so that the material is not deactivated before reacting with a substrate.
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