A structure comprising a metallic surface, a layer of a polymeric material and a water soluble polymeric material located between the metallic surface and the layer of polymeric material, and process of fabricating such are provided. The structure exhibits enhanced adhesion between the metallic surface and the polymeric material.

The present invention relates to improving the adhesion of a polymer to an underlying substrate and especially to an underlying metallic substrate such as copper.
In the manufacture of printed circuit cards and boards, a dielectric sheet material is employed as the substrate. A conductive circuit pattern is provided on one or both of the major surfaces of the substrate.
A conductive pattern can be formed on the surface of the substrate using a variety of known techniques. These known techniques include the subtractive technique and the additive technique. In the subtractive technique, a blanket layer of copper on the substrate is selectively etched to form the desired circuit pattern. It is well known to etch a pattern in the metallic surface such as copper by applying to the surface a photoresist, exposing the photoresist through a pattern of actinic radiation, removing the exposed or unexposed portion of the resist depending upon the type of resist to expose the underlying metal, and then etching the exposed metal with a suitable etchant. In the additive process, typically the photoresist is applied to the surface of the substrate, followed by being exposed through a pattern to actinic radiation and removing the exposed or unexposed portions of the resist depending upon the type of resist employed to expose the underlying substrate and the desired circuitry to be subsequently provided. Next, the exposed substrate is typically coated with a metallic layer such as copper from an electroless plating bath followed by electroplating to achieve the desired line thickness.
However, the bond of the photoresist or photoactive layer to the metal surface has not always been adequate, especially for exposure to various plating baths and/or etching compositions. However, as can be appreciated, the adhesion of photoresists to the underlying metallic surface is critical not only in fine-line subtractive circuitization, but also in other photoresist-based manufacturing processes such as pattern electroplating and solder mask applications. In solder mask applications, a photoactive polymeric solder mask is applied and defined by photolithographic techniques to uncover those underlying portions whereby solder is to be deposited while protecting other areas from having the solder deposit.
In view of the adhesion problems between these polymers and underlying metallic surfaces, a number of surface texturing/screening processes have been suggested for enhancing such adhesion. Some examples include providing pumice on foil copper to roughen its surface in the case of subtractive circuitization, sulfuric acid pretreatment of additive copper surfaces in the case of Sn/Pb electroplating, copper oxide treatment of copper in the case of certain solder mask applications, and vapor blast treatment of gold in the case of certain solder mask applications to chip carriers.
However, despite the attempts to enhance adhesion, failures which in turn result in the scrapping of product still occur periodically. The adhesion existing between photoactive polymers and underlying metallic substrates remains borderline, at most, in many cases. For instance, it has been observed that the interface between additive copper and various photoresists is susceptible to separation during immersion tin and subsequent Sn/Pb electroplating due to increased immersion times, photoresist mis-registration, and rinse impurities that might be present in the sulfuric acid pre-clean prior to applying the resist.
Accordingly, the need remains for providing enhanced adhesion between photoactive polymers and metallic surfaces in order to yield more robust as well as potentially more cost-effective, photoactive-based processes.
The present invention provides for improved bonding of polymers to metallic surfaces. It has been found according to the present invention that polymers can be firmly and adherently bound to the desired metallic surface by employing a water soluble polymeric material, which prevents xe2x80x9ccurlingxe2x80x9d or lifting of the other polymer from the metallic surface and, consequently, prevents undercutting during etching in the case of photoactive polymers.
In particular, the adhesion between the polymer and metallic surface is enhanced by providing a layer of a water soluble polymeric material between the polymer and the metal surface. Specifically, the present invention is directed to a structure which comprises a metallic surface, a layer of a first polymeric material and a water soluble polymeric material located between the metallic surface and the layer of the first polymeric material.
The present invention is also directed to a process for fabricating the above structure which comprises the steps of providing a metallic surface, providing a water soluble polymeric material on the metallic surface and providing a layer of a polymeric material on the water soluble polymeric material.
In addition, the present invention relates to an electronic package that comprises a substrate, a metallic conductive layer on the substrate, a water soluble polymeric material on the metallic conductive layer and a polymeric layer located on the water soluble polymeric material wherein the polymeric layer has been developed to provide a pattern corresponding to desired circuitry.
The present invention also relates to a process for fabricating the above-defined electronic package which comprises providing a substrate and a metallic conductive layer on the substrate, providing a water soluble polymeric material located on the conductive layer, providing a photoactive polymeric film on the water soluble polymeric material, imagewise exposing the photoactive polymeric material to actinic light, and developing by removing photoactive film.
Still other objects and advantages of the present invention will become readily apparent by those skilled in the art from the following detailed description, wherein it is shown and described only the preferred embodiments of the invention, simply by way of illustration of the best mode contemplated of carrying out the invention. 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, without departing from the invention. Accordingly, the description is to be regarded as illustrative in nature and not as restrictive.
The present invention relates to improving the adhesion of polymeric materials and especially photoactive polymeric materials to a variety of metallic conductive surfaces. Examples of suitable metals include copper, gold, aluminum, silver, alloys of these metals and conductive metallic compounds such as metallic silicides and titanates. Other suitable metals include titanium, niobium, tantalum and tungsten. The preferred metal is copper and copper alloys such as copper aluminum alloys.
In a typical structure, the metallic conductive layer is present on an underlying substrate such as a dielectric substrate. Typical dielectric substrates employed in fabricating printed circuit cards and boards include thermoplastic and thermosetting resins. Typical thermosetting polymeric materials include epoxy, phenolic base materials and polyamides. The dielectric material may be molded articles of the polymers containing fillers and/or reinforcing agents such as glass filled epoxy or phenolic based materials. Examples of some suitable thermoplastic polymeric materials include polyolefins such as polypropylene, polysulfones, polycarbonates, nitrile rubbers and ABS polymers.
In accordance with the present invention, the metallic surface is treated or coated with a water soluble polymeric material. The water soluble polymers employed according to the present invention typically have weight average molecular weights of at least about 100,000 and more typically about 500,000 to about 1,000,000. The water soluble polymeric materials include both ionic polymeric materials and non-ionic polymeric materials. Examples of some suitable water soluble polymeric materials include polymers of acrylamides, amidoamines and acrylic acids. The polymers include homopolymers and copolymers. The cationic polyacrylamides typically include at least two active or available cationic functional moieties such as quaternary phosphonium and quaternary ammonium groups. Suitable cationic polyacrylamide is commercially available under the trade designation POLYTEC 7M from Polyset, Inc. Another cationic polymer commercially available is a cationic polyamidoamine under the trade designation CARTARETIN available from Sandoz Chemicals. A commercially available non-ionic polyacrylamide is available under the trade designation POLYTEC 31PX from Polytec, Inc.
The polymers are typically applied to the metallic surface as a dilute aqueous solution of about 0.005 to about 5% by weight and more typically about 0.03 to about 0.7% by weight of the polymer. The aqueous solution also typically contains an acid such as sulfuric acid or hydrochloric acid to provide a pH value of usually up to about 3, more usually up to about 2 and preferably about 0 to about 1. The low pH values are preferred in order to obtain a relatively low viscosity for the polymer solution to thereby facilitate applying it. The acid is generally present in amounts of about 0.001 N to about 1 N.
The treatment with the water soluble polymer generally requires about 1 to about 10 minutes and more typically about 2 to about 4 minutes. The water soluble polymeric material provides a more hydrophilic surface on the metallic surface. The water soluble polymeric material can be a monolayer or even less than a monolayer whereby the water soluble polymer does not coat the entire metallic surface but at least 25% of the surface.
A typical composition is employed at about 0.6 grams/liter of POLYTEC 7M in an aqueous sulfuric acid solution at a pH between 0 and 1.
The water soluble polymers are significantly more hydrophilic than the other polymers such as the photoactive polymeric materials which are not water soluble and enhances its hydrophilic nature whether the photoactive polymeric materials are hydrophobic or hydrophilic. The water soluble polymers in solid form have a contact angle with water of zero, whereas the photoactive polymers or other polymers employed have a contact angle with water greater than zero.
The photoactive polymeric material includes those used in photoresist based processes such as subtractive techniques, patterned electroplating, and solder mask applications. The photoactive polymers can be hydrophilic polymers and include acrylate and methacrylate based photoactive polymers including epoxy-acrylate and/or epoxy-methacrylate mixtures. Typically, these polymers are from polymethylmethacrylate along with a poly-functional hydrophilic acrylate ester. Suitable commercially available photoactive polymers include CFI, MI, Platemaster, T168, and Vacrel. Vacrel is an example of a dry film photoresist that finds especial utility as a solder mask. In a typical process, the photoactive material is subjected imagewise to a suitable actinic light pattern. Depending upon whether the photoactive material is a positive photoactive material or a negative active material, either the exposed or unexposed regions respectively will be removed with a suitable solvent for developing the desired pattern. After this, the pattern of the metallic conductive layer can then be provided either by subtractive or additive plating, depending upon the technique being employed. Subsequent to forming the desired conductive pattern, the remaining photoresist and water soluble polymer are then removed employing suitable solvents.
The following non-limiting examples are presented to further illustrate the present invention.

Promoting adhesion between a polymer and a metallic substrate

International Business Machines Corporation


A roofing apparatus for forming round, square, and oval rooms utilizing channel beams and interlocking roof panels. A system and method for utilizing vinyl as a construction material for forming roofing system is taught along with the use of connecting spiders, connection blocks, and insulated and sheathed vinyl panels. The system teaches the use of a non-thermally conductive I-beam for forming a roof system for improved insulation and long-term longevity of building structures.

The present invention relates generally to roofing systems for buildings and sunroom additions to homes. More particularly, this invention pertains to a method and apparatus for constructing a roof from an extruded material for improved thermal characteristics and stability.
FIG. 1 of the drawings shows a prior art profile of a metal I-beam 10. The design utilizes a top planar member 12, a vertical planar member 14, and a bottom planar member 16. While the metal I-beam 10 design is well recognized in standard construction techniques and assemblies, This design is limited in its functionality and effective utilization of materials.
Prior art disclosures are found in a multitude of U.S. Pat. Nos. including 2,947,040 issued to Schultz on Aug. 2, 1960; 3,055,461 issued to Ridder on Sep. 25, 1962; 3,096,861 issued to Frick et al. on Jul. 9, 1963; 3,340,657 issued to Thomas on Sep. 12, 1967; 3,345,794 issued to Proud on Oct. 10, 1967; 3,562,992 issued to Kinsey on Feb. 16, 1971; 3,733,756 issued to Butler on May 22, 1973; 3,760,544 issued to Hawes et al. on Sep. 25, 1973; 3,805,470 issued to Brown on Apr. 23, 1974; 3,848,387 issued to Hafner on Nov. 19, 1974; 3,952,461 issued to Kinsey on Apr. 27, 1976; 3,978,629 issued to Echols, Sr. on Sep. 7, 1976; 4,040,219 issued to Budich on Aug. 9, 1977; 4,057,941 issued to Schwartz on Nov. 15, 1977; 4,069,627 issued to Pegg on Jan. 24, 1978; 4,110,942 issued to Slocomb, Jr. on Sep. 5, 1978; 4,167,838 issued to Metheny on Sep. 18, 1979; 4,583,333 issued to Minter on Apr. 22, 1986; 4,594,828 issued to Taylor on Jun. 17, 1986; 4,601,139 issued to Esposito on Jul. 22, 1986; 4,724,646 issued to Meyers on Feb. 16, 1988; 4,745,723 issued to Esposito on May 24, 1988; 4,765,102 issued to Kuchem on Aug. 23, 1988; 4,773,193 issued to Biebuyck et al. on Sep. 27, 1988; 4,796,395 issued to Israel on Jan. 10, 1989; 4,884,376 issued to DeBlock et al. on Dec. 5, 1989; 4,903,455 issued to Veazey on Feb. 27, 1990; 4,918,882 issued to Funk on Apr. 24, 1990; 5,003,733 issued to Strobl, Jr. et al. on Apr. 2, 1991; 5,007,215 issued to Minter on Apr. 16, 1991; 5,046,791 issued to Kooiman on Sep. 10, 1991; 5,090,164 issued to Mische on Feb. 25, 1992; 5,125,207 issued to Strobl, Jr. et al. on Jun. 30, 1992; 5,197,253 issued to Johnson on Mar. 30, 1993; 5,293,728 issued to Christopher et al. on Mar. 15, 1994; 5,325,647 issued to Forry et al. on Jul. 5, 1994; 5,363,615 issued to Christopher et al. on Nov. 15, 1994; 5,394,664 issued to Nowell on Mar. 7, 1995; 5,555,681 issued to Cawthon on Sep. 17, 1996; 5,560,155 issued to Back on Oct. 1, 1996; 5,568,707 issued to Ishikawa et al. on Oct. 29, 1996; 5,608,997 issued to Mahowich on Mar. 11, 1997; 5,771,640 issued to Back on Jun. 30, 1998; 5,783,286 issued to DiNicola on Jul. 21, 1998; 5,792,529 issued to May on Aug. 11, 1998; Design Patent Des. 327,744 issued to Francis on Jul. 7, 1992; and Swiss Patent No. 459 516. These patents are hereby incorporated by reference.
A representative number of these patents will be reviewed in the following discussion:
U.S. Pat. No. 3,760,544 issued to Hawes et al. on Sep. 25, 1973, discloses a SEALING GASKET WITH ELONGATED INTERNAL STIFFENER. This specification is directed towards an extruded plastic gasket which is constructed with a full length of strip or insert of a different material in the gasket. This inner material is utilized to strengthen the portion of the gasket in which it is located and reduce any creeping or other movement of the gasket after it has been installed.
U.S. Pat. No. 3,952,461 issued to Kinsey on Apr. 27, 1976, discloses MULTI-LAYER WALLS FOR FRAMELESS BUILDINGS FORMED FROM EXTRUDED ALUMINUM OR PLASTIC INTERLOCKING WALL ELEMENTS. FIG. 20 of this application describes the use of a sub-comb having upwardly facing, angularly disposed surfaces for engaging and supporting the upper ends of the metallic roof rafters. As noted by the remainder of the specification, the specification is directed towards a multi-layer wall structure which utilizes so extruded wall elements to interlock and form a frameless multi-story building complex.
U.S. Pat. No. 4,601,139 issued to Esposito on Jul. 22, 1986, discloses a METHOD AND FRAMEWORK FOR A GREENHOUSE OR THE LIKE INCLUDING A REVERSIBLE GABLE ADAPTER. As noted in FIG. 8 of the drawings, wedge-shaped adapters is utilized to join vertical bars with sloped bars. This adapter is inserted into a chamber using the prong of the adapter.
U.S. Pat. No. 5,046,791 issued to Kooiman on Sep. 10, 1991, discloses an Extrusion Frame and Components Therefor. This specification is directed towards the framing of cabinetry and the like which utilizes a connecting element for joining extrusion frame components.
U.S. Pat. No. 5,325,647 issued to Forry et al. on Jul. 5, 1994, discloses a Composite Ceiling Grid. This specification is directed towards ceiling grid runners and the associated method of assembly which utilizes metal reinforced thermal plastic compounds. This system utilizes the metal in strategically positioned areas to maximize the strength ratio of the plastic.
U.S. Pat. No. 5,555,681 issued to Cawthon on Sep. 17, 1996, discloses a Modular Building System. This specification is directed towards the construction of various light structures. An octagonal cap is described which may be separated to serve as an Apex for a quarter-end structure for a shed like addition. As shown in FIG. 13 of the drawings, a roof ridge member may be used to form the roof ridge or crest of a gabled structure.
U.S. Pat. No. 5,792,529 issued to May on Aug. 11, 1998, discloses a Reinforced Plastic Extrusion. This specification describes the use of three different extrusions in order to form a single configuration with increased components strength and stiffness. Thus, the desired profile is extruded which allows for the strategic placement within a profile to obtain optimum strength and stiffness.
Prior art aluminum roofing systems for additions or sunrooms are well known. These sunrooms pose certain problems during their life. Aluminum works as an excellent heat conductor as evidenced by its use in a variety of heat dissipation applications. However, this high thermal conductivity causes several problems in roofing systems. Aluminum roofing systems transfer cold from the outside of a structure to the interior environment. This heat transfer can lead to condensation on the interior roof of the structure, and the transfer of interior heat to the outside environment results in thermal inefficiencies. In addition, aluminum structures are rigid and may dent, scratch, or be punctured due to contact with normal everyday items such as lawn mower, foot traffic, or wind blown debris. Thus, the present art of aluminum roof construction has several disadvantages. can lead to condensation on the interior roof of the structure, and the transfer of interior heat to the outside environment results in thermal inefficiencies. In addition, aluminum structures are rigid and may dent, scratch, or be punctured due to contact with normal everyday items such as lawn mower, foot traffic, or wind blown debris. Thus, the present art of aluminum roof construction has several disadvantages.
Thus, the prior art patents teach limited structures which pose problems for temperature variations, normal wear and tear associated with buildings, and long term stability. What is needed, then, is an improved method and apparatus for constructing buildings with increased efficiency.
The present invention is directed towards a vinyl roofing system utilizing beams to inter-connect roof panels with a roof cap for providing a roof structure. The system may utilize a connecting spider for forming rounded roofing systems, and an upper and lower roof cap for connecting the roofing system together. The system may utilize channel beams with top and bottom plates with a plurality of vertical members to form a center aperture. This center aperture may be utilized with a beam filler, and may also be utilized as a raceway for electrical, water, or other connections within the structure. A further embodiment of the present invention utilizes channel V-beams to form a rounded roofing system for efficient roofing construction and methods. These beams may utilize end caps for completing the structural appearance and integrity of the building.
Different connecting blocks and means are taught for connecting the various rafters together. Different panels including vinyl sheathing panels, insulated and polycarbonate panels, as well as polycarbonate panels are taught in the present invention which may utilize fascia caps for protecting the ends of the panels, or the sheathing may wrap over edges to cover adjacent surfaces of the roofing panels.


A system for lifting a vehicle via multiple slings comprises a vehicle not engineered with structural facility to withstand lifting forces, including a frame which unmodified will deform in response to vertically imposed lifting forces, frame reinforcing elements affixed to the frame at selected locations which are subject to lifting deformation, at least two lifting members at spaced-apart forward frame locations, at least two lifting members at spaced-apart rearward frame locations, and a plurality of elongate slings extending respectively between each lifting member and a common lifting vertex. Each lifting member has an enlarged lower base portion rigidly affixed to the frame and an upper lifting portion. The frame reinforcing elements resist deformation of the frame in response to vertically imposed lifting forces. The enlarged base portions of the lifting members apply forces over a correspondingly enlarged area of the frame and the reinforcing elements without deforming the frame.

Military-specific automotive vehicles are often moved or transported from one location to another via a lifting system utilizing multiple elongate slings extending between a common lifting vertex and spaced apart connection points on the vehicle, e.g., for lifting vehicles by a crane to load and off-load vehicles from trucks, ships, railway cars, etc., or for more distant transport of a vehicle by a sling system suspended from a transport helicopter or other aircraft.
By contrast, however, most passenger and other commercially produced vehicles sold to the general public are not suitable for movement or transport via a sling lifting system. The frame components used in such vehicles are engineered in configurations designed to receive horizontally imposed forces as may occur in accidents with other horizontally moving vehicles, but otherwise the frame components in such commercially produced general purpose vehicles are typically relatively thin-walled and not suitable to withstand vertically applied forces on the order of forces as would occur during a sling lifting operation without deformation or damage to the vehicle frame.
Furthermore, as automotive safety technology applicable to passenger and other commercial vehicles has advanced in recent years, automotive engineers have learned that increased rigidity and strength of vehicle frame and body components does not necessarily promote or insure the safety of vehicle passengers and occupants, but to the contrary can be harmful to the extent that forces exerted on a vehicle in a crash or other accident can be transmitted unabated directly to occupants by a rigid vehicle structure. Accordingly, it has become commonplace for vehicle designs to include frame and body components designed to deform under forces generated in an accident, usually referred to as "crumple zones," intended to absorb such forces and thereby mitigate the forces imposed on vehicle occupants. However, such deformation or crumple zones exacerbate the inability of commercial vehicle frames to withstand vertical lifting forces exerted by sling lifting systems when moving and transporting vehicles as the forces exerted in lifting vehicles can be transmitted through the slings to cause deformation to the frame or body components in the regions of the crumple zones.
The sling lifting of military vehicles via military aircraft presents even greater concerns in avoiding potential frame damage to the vehicles. Hence, military specifications, e.g., U.S. Department of Defense Specifications MIL-STD-209, MIL-STD 913, and MIL-STD 1366, specify standardized requirements for sling lifting of military vehicles. Military vehicles are typically manufactured with reinforced structural frames that do not include crumple or deformation zones, and therefore are less subject to potential damage under the loading forces imposed during sling lifting operations. Various commercially produced general purpose vehicles could offer advantages if adapted for military use, but would almost certainly suffer frame or body damage or deformation under such sling loading forces.
Accordingly, a need exists for an improved system for sling lifting of vehicles providing greater resistance to loading forces to prevent damage to vehicle frame components, e.g., crumple zones in vehicle frames. In turn, such an improved lifting system could greatly expand the possibilities for military adaptation of vehicles not originally built for military purposes.

System for lifting, moving and transporting a vehicle via multiple slings connected to a common lifting vertex, and method of retrofitting a vehicle to facilitate lifting

Hendrick Motorsports Performance Group, LLC


Displacement machines for compressible media having single-threaded, twin screw rotors with continuously decreasing pitch to achieve an inner compression are known. The demand for compact pumps with rotors as short as possible, and the frequent, process-related demand for quick disassembly of the housing, set limits however for the wrapping angle or respectively for the variation of the end profiles, which, in turn, leads to extreme pitch ratios or to insufficient compression rates. The present invention uses screw rotors with an optimized, non-monotone pitch course and alternative end profile variation with constant diameters. Suction capability is improved with the same space requirement, and compression rates of 3.0 and more are achieved easily with only four wraps. Displacement machines equipped with such twin screw rotors provide optimal results with respect to energy requirement, temperature, construction space and servicing with application possibilities in chemistry and in semiconductor technology.

The invention relates to twin screw rotors for installation in displacement machines for compressible media, in particular pumps, which rotors are designed single-threaded with varying pitch and are intended to be in axis-parallel, opposed, outside engagement with wrapping angles of at least 720xc2x0, and to form in a housing an axial sequence of chambers without blow-hole connections, the end profile comprising a core arc of a circle, cycloidal hollow flank, an outer arc of a circle and a further flank.
The patent DE 87685 shows a machine called a screw wheel capsule mechanism, in which the screw rotors are designed with variable pitch. The machine can be used both as a motor and as a pump. In order to additionally increase the volume of the working chambers in the direction of the expanding medium, when operating as a motor, the rotors are alternatively constructed tapering.
Described in the patent DE 609405 is an air cooling machine with compressor and expander, which both have screw pairs with variable pitch and thread depth. The enveloping surfaces of the rotors are designed tapering.
Both of the aforementioned machines have the drawback that they require tapering cylinders, whereby the rotors can be put in and taken out on one side only. This increases the expenditure (of time and effort) during assembly and disassembly of the machines, which is very disadvantageous in particular during maintenance and repair work.
The patent application EP 0 697 523 concerns a screw-type displacement machine in which the rotors meshing with one another have unequal screw profiles, designated as xe2x80x9cmalexe2x80x9d and xe2x80x9cfemalexe2x80x9d, so-called S.R.M. profiles with continuous change of the pitch. The end profile is thereby varied in such a way that the angle of the tooth tip, or respectively the length of outer arc is a monotonically increasing function dependent upon the wrapping angle. Such profiles have the drawback that a good partitioning of the axial sequence of working cells is not possible owing to the remaining blow hole. The vacuum losses caused by the blow hole result in losses in degree of efficiency, so that with such a machine no good inner compression is possible at least at low and medium rotational speeds.
The published patent application DE 19530662 discloses a screw suction pump with outer combing screw elements, in which the pitch of the screw elements continuously decreases from their inlet end to their outlet end to cause the compression of the gas to be released. The shape of the teeth of the screw rotor has an epitrochoidal and/or Archimedean curve. This machine has the disadvantage that the achievable inner compression rate with the shown geometric proportions is mediocre. Moreover the lacking end profile variation sets the already not good compression ratio, and leads to an increased leak rate owing to the reduction in the depth of the gap between screw outer diameter and housing toward the screw end.
The published patent application DE 4445958 describes a screw compressor with opposite-running, rotating outer combing screw elements. The threading helices of the screw elements become continuously smaller from one axial end to the second axial end removed therefrom. Proposed as a profile is a rectangular or trapezoidal profile. A drawback of these kinds of geometry for the profile is that they work sufficiently loss-free only if the thread depth is minimal with respect to the diameter, as is explained in the said publication. Such a machine therefore has a large constructional volume and a great weight. It is a further drawback of such profile geometry that extremely high changes in pitch are necessary if a satisfactory inner compression rate is supposed to be achieved. As with the mentioned DE 19530662, the lacking end profile variation here too fixes this shortcoming, and this leads to a high leak rate owing to the reduction of the depth of the gap between screw outer diameter and housing toward the screw end.
Further publications, such as, for example, SE 85331, DE 2434782 and DE 2434784, concern inner-axial screw machines with non-constant pitch of the screws or varying end profiles. These machines all have the drawback that the construction cost is high, and that in each case dynamic seals are also required suction-side.
Furthermore there are some publications, for example DE 2934065, DE 2944714, DE 3332707 and AU 261792, which describe two-shaft compressors with screw-like rotors. There the rotors, and in some cases the housing too, are composed of profile disks of differing thickness and/or contour, disposed axially behind one another, and thus achieve inner compression. All machines with screw-like rotors have the drawback that their degree of efficiency is decreased compared to that of machines with screw-shaped rotors because detrimental spaces and whirl zones arise through the stepped construction. Furthermore problems with respect to shape consistency are to be expected with screw-like rotors since they heat up in operation.
Starting with this state of the art, the invention has as its object to propose a twin screw rotor which does not have the above-mentioned drawbacks.
These objects are attained, according to the invention, in that the pitch is not monotone and is defined as a variable dependent upon the wrapping angle, in that the pitch in a first section increases from the suction-side screw end, and reaches a maximal value after approximately one turn, in that the pitch in a second section, adjacent to the first section, decreases and reaches a minimal value at approximately one turn before the delivery side screw end, and in that the pitch in a third section, adjacent to the second section, remains substantially constant.
Special embodiments of the invention are described in the dependent claims.

Twin screw rotors for installation in displacement machines for compressible media


Structured surfaces are generated in a coil coating line operating at least at 60 m/min by a process comprising the step of passing the wet layer of paint under a roll having a raised pattern on its surface that imparts a structure to the wet layer before heating to form a coating having a structured surface. The paint has a viscosity of 30 to 200 s (DIN 4 cup; DIN 53211).

It is known in the art of coil coating that structured surfaces can be obtained by changing the chemical composition of the paint (see e.g. the papers by P. Kunze in Oberflaeche-JOT, 1991(7), pages 40, 42 and 43, and by L. Jandel presented at the Workshop Coil Coating of the BSHG AK Oberflachentechnik held on 30.06.94 at Giengen, Germany). Paint as used herein defines as well primers as topcoats or even tie coats.
The incorporation of large particles (i.e. of a size larger than the thickness of the dry paint layer) in the paint, in the form of inert or reactive pigments or fillers, gives a structured coating depending on the particle size.
The incorporation in the paint of an additive which provokes an incompatibility (whether in the paint or during the curing process) also gives a structured surface depending on the incompatibility.
EP-A-47508 to SCHRAMM Lacke discloses the use of a finely divided polyamide suspended in a thermosetting paint with a hydroxyl-functional binder and a blocked polyiscyanate.
EP-A-288294 to BASF Lacke+Farben discloses the use of 0.01 to 0.05 wt % of polyethylene wax having a softening point of 100-120.degree. C. and a particle size of 5-35 um in the primer of certain polyester systems to obtain a structured finish.
DE-A-4019318 to BASF Lacke+Farben discloses the use of certain siloxanes in one or two-coat polyester compositions to obtain a structured surface.
The state of the art technology has many drawbacks. The main drawback is that changing the pattern of the structure requires changing the composition of the paint. Also, raw materials variability makes it difficult to reproduce the same structure from batch to batch. In addition, the structure pattern can in many cases be different in the web direction and in the transverse direction. Further, the systems based on the creation of an incompatibility are inherently subject to storage stability problems.
Mechanical means for making structured surfaces have already been proposed.
U.S. Pat. No. 5,565,260 discloses a method for applying polymer resin having a solids content of at least about 50 wt vol % with a coating roll having grooves in its surface.
U.S. Pat. No. 3,207,617 discloses a method for painting an embossed pattern on individual sheets of plywood, hardboard and the like, comprising applying a coat of liquid paint, mixing sand with said paint, and rolling a grooved roller to provide an embossed pattern.
FR-A-2,289,353 discloses a process for making an embossed coating on a substrate, wherein means for embossing are applied on a coating of a composition having a viscosity of 20 to 1,000 poises (dPa.s) whilst said coating in drying.
GB-1,512,967 discloses a process for making a decorative relief finish on a substrate such as a wall, using a pressing roll made of polyvinyl alcohol or polyvinyl acetal. The materials used to form the coatings are conventionally used in the building art to form thick films; exemplified materials have viscosities of 150 and 480 poise (dPa.s).
EP-A-79,759 discloses a method for providing surface replication in a coating on a sheet of material, wherein the coated sheet is at least partially set while it is pressed against a replicative surface. Such a process could not be adapted to coil coating because the continuous sheet must pass horizontally in the ovens
These mechanical means have one or more of the following drawbacks:
they demand the use of highly viscous coating compositions, which could not be used in coil coating; PA1 they cannot be used continuously, or where they can they have a low speed that cannot compare with the high speed of coil coating; and/or PA1 the structure has to be imparted during the drying step, what is obviously impossible in a coil coating oven. PA1 (a) applying a wet layer of a paint on a substrate, the paint having a viscosity of 30 to 200 s (as measured with a DIN 4 cup using DIN 53211 standard-method) and the substrate moving at a speed of at least 60 m/min; PA1 (b) passing the wet layer of paint under a roll having a raised pattern on its surface that imparts a structure to the wet layer; then PA1 (c) heating the thus coated and rolled substrate to form the structured surface.
There is thus a need in the art for a process for generating structured surfaces in coil coating which would not suffer from those drawbacks.
It is thus an object of the invention to provide a process for generating structured surfaces in coil coating that allows to change the structure pattern without having to change the paint composition.
It is another object of the invention to provide a process for generating structured surfaces in coil coating that will be essentially independent from the usual raw materials variability.
A further object of the invention is to provide a process for generating structured surfaces in coil coating that will not create paint storage stability problems.
These and other objects can be achieved by the process of the invention.
The process of the invention for generating a structured surface in coil coating comprises the successive steps of:
Coil coating is a continuous coating process of metal coils. The metal is generally steel, galvanised steel or aluminium. The coating is applied continuously on the metal moving at high speed, using roller or spraying applications and dried or cured by passing in a heated oven. The process involves metal pretreatment (such as degreasing, brushing, rinsing and chemical treatment, as may be required or desired) followed by the application and heating of two layers of coating (generally a primer and a topcoat). The coated metal can then be cut and given its final shape. Description of the coil coating process can be found in many textbooks, e.g. in "Organic Coatings: Science and Technology", vol.II, pages 290-5, Wicks et al., eds., Wiley, 1994.
The process of the invention can be applied to the primer and/or to the topcoat (or to any intermediate coat). When a primer is structured, it is known that it can be overcoated with a topcoat which essentially retains the structure imparted to the primer coat.
The wet layer of paint can be applied by any means used or useable in coil coating, such as bar coating, roller coating, curtain coating or extrusion. The wet film usually has a thickness of from 5 to 60 .mu.m; for primers the wet film thickness is preferably of about 20 .mu.m, while for topcoats it is preferably of about 50 .mu.m.
The invention is applicable to any type of paint that can be used in coil coating, be it of the heat curing or of the heat drying type. As examples of binders, there can be cited epoxy resins, polyesters, polyurethanes, polyesterurethanes, silicone-polyesters, PVC plastisols and organosols, polyvinylidene fluoride (PVdF) homo- or copolymers, and hybrid formulations as well as mixtures. Paint formulation in coil coating is known in the art and need not be described herein.
As in any other coil coating process, the paint properties (such as the thixotropy, the viscosity, the curing reaction) need to be adapted to the specific operating conditions. The viscosity of the paint is typically in the range of 30 to 200 s (as measured with a DIN 4 cup; DIN 53211 standard method), preferably 50 to 150 s, more preferably 60 to 120 s.
The heating step of the coated substrate to cure the paint is well known in the art; more particularly, one of ordinary skill in the art knows how to adapt the heating conditions.
The wet layer of paint is passed under a roll having a raised pattern on its surface in order to impart a structure to the wet layer before heating it to cure the paint. The roll may be made of any material, such as steel, stainless steel, brass, rubber, or it may even comprise a rubber coating on a metal roll. The diameter of the roll is easily adapted to the linear speed of the coil; the diameter is typically of from 10 to 2000 mm.
The raised pattern may be regular or irregular, any pattern design may be used. Typical dimensions are in the range of from 0.2 to 100 mm for the pattern unit and independently from 0.1 to 50 mm for each of the raised and hollow parts of the pattern. One of the advantages of the invention over the prior art is that it allows to obtain patterns of practically any unit size, whereas the prior art only provides small unit sizes (lower than 1 mm).
The depth of the pattern can be of from 0.01 to 10 mm, depending on the desired structure.
The distance between the surface of the raised pattern and the adjacent surface of the substrate is adapted to the desired depth of the structure, with the usual accuracy required in coil coating.
The structure created in the wet layer of paint is fixed by the curing process in the heating step. Said heating step must follow within a short period of time, which essentially depends on the viscosity and thixotropy of the wet paint; the speed of the coil in the process of the invention being of at least 60 m/min, preferably at least 80 m/min, there is no difficulty in placing the roll sufficiently close to the location where the paint will be cured, so that the paint viscosities and thixotropies usual in coil coating can be used.
The invention is thus suitable for all standard primer, intermediate and top coating compositions that can be used in coil coating.
The process of the invention provides a coil coating system which is simple to use and does not require any modification of the composition of the paints. In addition, the pattern of the structure can be varied practically at will and without interfering with the properties of the coating, what is impossible when varying the composition of the paints
A coil coating apparatus essentially comprises the following elements, in that order: a decoiler, a stitching or welding unit, an entry accumulator, a pretreatment zone, a first coating unit followed by an oven, a second coating unit followed by an oven, an exit accumulator, and a recoiling or shearing and stacking equipment.
The present invention also provides a coil coating apparatus characterised in that it comprises, between a coating unit and the oven following it, a roll having a raised pattern on its surface that is adapted to impart a structure to the wet layer of coating before it is heated.
This invention provides the first opportunity to adjust in a coil coating process the general image of the structure pattern, the dimension of the unit of a repeated motive and the slope of each single motive.

Process for generating structured surfaces in coil coating

Sigma Coatings Farben- und Lackwerke GmbH


A digital image of the object is captured and the object is recognized from plurality of objects in a database. An information address corresponding to the object is then used to access information and initiate communication pertinent to the object.

There is a need to provide hyperlink functionality in known objects without modification to the objects, through reliably detecting and identifying the objects based only on the appearance of the object, and then locating and supplying information pertinent to the object or initiating communications pertinent to the object by supplying an information address, such as a Uniform Resource Locator (URL), pertinent to the object.
There is a need to determine the position and orientation of known objects based only on imagery of the objects.
The detection, identification, determination of position and orientation, and subsequent information provision and communication must occur without modification or disfigurement of the object, without the need for any marks, symbols, codes, barcodes, or characters on the object, without the need to touch or disturb the object, without the need for special lighting other than that required for normal human vision, without the need for any communication device (radio frequency, infrared, etc.) to be attached to or nearby the object, and without human assistance in the identification process. The objects to be detected and identified may be 3-dimensional objects, 2-dimensional images (e.g., on paper), or 2-dimensional images of 3-dimensional objects, or human beings.
There is a need to provide such identification and hyperlink services to persons using mobile computing devices, such as Personal Digital Assistants (PDAs) and cellular telephones.
There is a need to provide such identification and hyperlink services to machines, such as factory robots and spacecraft.
Examples include:
identifying pictures or other art in a museum, where it is desired to provide additional information about such art objects to museum visitors via mobile wireless devices;
provision of content (information, text, graphics, music, video, etc.), communications, and transaction mechanisms between companies and individuals, via networks (wireless or otherwise) initiated by the individuals "pointing and clicking" with camera-equipped mobile devices on magazine advertisements, posters, billboards, consumer products, music or video disks or tapes, buildings, vehicles, etc.;
establishment of a communications link with a machine, such a vending machine or information kiosk, by "pointing and clicking" on the machine with a camera-equipped mobile wireless device and then execution of communications or transactions between the mobile wireless device and the machine;
identification of objects or parts in a factory, such as on an assembly line, by capturing an image of the objects or parts, and then providing information pertinent to the identified objects or parts;
identification of apart of a machine, such as an aircraft part, by a technician "pointing and clicking" on the part with a camera-equipped mobile wireless device, and then supplying pertinent content to the technician, such maintenance instructions or history for the identified part;
identification or screening of individual(s) by a security officer "pointing and clicking" a camera-equipped mobile wireless device at the individual(s) and then receiving identification information pertinent to the individuals after the individuals have been identified by face recognition software;
identification, screening, or validation of documents, such as passports, by a security officer "pointing and clicking" a camera-equipped device at the document and receiving a response from a remote computer;
determination of the position and orientation of an object in space by a spacecraft nearby the object, based an imagery of the object, so that the spacecraft can maneuver relative to the object or execute a rendezvous with the object;
identification of objects from aircraft or spacecraft by capturing imagery of the objects and then identifying the objects via image recognition performed on a local or remote computer;
watching movie previews streamed to a camera-equipped wireless device by "pointing, and clicking" with such a device on a movie theatre sign or poster, or on a digital video disc box or videotape box;
listening to audio recording samples streamed to a camera-equipped wireless device by "pointing and clicking" with such a device on a compact disk (CD) box, videotape box, or print media advertisement;
purchasing movie, concert, or sporting event tickets by "pointing and clicking" on a theater, advertisement, or other object with a camera-equipped wireless device;
purchasing an item by "pointing and clicking" on the object with a camera-equipped wireless device and thus initiating a transaction;
interacting with television programming by "pointing and clicking" at the television screen with a camera-equipped device, thus capturing an image of the screen content and having that image sent to a remote computer and identified, thus initiating interaction based on the screen content received (an example is purchasing an item on the television screen by "pointing and clicking" at the screen when the item is on the screen);
interacting with a computer-system based game and with other players of the game by "pointing and clicking" on objects in the physical environment that are considered to be part of the game;
paying a bus fare by "pointing and clicking" with a mobile wireless camera-equipped device, on a fare machine in a bus, and thus establishing a communications link between the device and the flue machine and enabling the fare payment transaction;
establishment of a communication between a mobile wireless camera-equipped device and a computer with an Internet connection by "pointing and clicking" with the device on the computer and thus providing to the mobile device an Internet address at which it can communicate with the computer, thus establishing communications with the computer despite the absence of a local network or any direct communication between the device and the computer;
use of a mobile wireless camera-equipped device as a point-of-sale terminal by, for example, "pointing and clicking" on an item to be purchased, thus identifying the item and initiating a transaction.

This patent is subject to a terminal disclaimer.

Image capture and identification system and process


A method, system, and apparatus, including a program encoded on computer-readable medium, for transmitting data to a server. A wireless communication connection is established between a first computing device and a second computing device. Data transmitted from the first computing device to the second computing device is received over the wireless communication connection and stored on the second computing device for uploading to a server on an IP based network. The wireless communication connection is disconnected. An IP communication connection is established between the second computing device and the server on the IP based network, and at least a portion of the stored data is transmitted from the second computing device to the server on the IP based network over the IP communication connection after the wireless communication connection between the first computing device and the second computing device is disconnected.

Currently, there is a growing number of WiFi public hot-spots (or Access Points—"AP"). These APs allow WiFi-enabled devices (which we refer to as STA) that are in their coverage area to Connect to the internet.
Some of the APs are operated as a business, service, or as part of a community, either with or without a charge to the STA's owner. Other APs are placed by individuals in their premises, but are not "locked", i.e., they are "open", allowing bypassing STAs to 4utilize them. Other APs placed by individuals are "locked" (or "closed"), thus not allowing passing STAs to utilize them.
As APs are being deployed in growing numbers, many individuals lock their APs for fear of unfair use of their network resources, and due to security concerns. For instance, there have been cases where a person places an open AP, and his neighbor uses this AP as its internet connection on a full-time basis without the consent of the first person, thus abusing and degrading the service of the first individual, in other cases, the neighbor hacked into the computer of the first person through the network. Thus, as time passes, most APs are either locked, or a payment is required to use them. Although the total number of APs and their area of coverage is growing fast, a larger percent of the APs are becoming locked and inaccessible to roaming STAs.
A prior art approach for allowing roaming customers to access the Internet is taken by Fon (www.fon.com), it allows individuals to download a new software into their APs, which makes their APs a pay-for-use APs for STAs that roam in their vicinity, and in addition, they receive a username and password for free access to other APs which are operated by Fon or utilize their software. It also allows users to enjoy part of some of the payments made by other users to use the network. However, roaming STAs are forced either to find an open AP, find an AP for which they have an account or pay for access in case there is a pay-for AP.
It is an aim of the current disclosure to provide a system and a method for deployment of APs for the purpose of connecting STAs to the Internet,
Roaming customers that connect to an AP are often far from the AP and have borderline reception conditions. As a result, the connection quality is very poor, and the user may experience a slow service or no service at all. It is another aim of the current disclosure to provide a system and a method for improving the connection quality for roaming STAs.
Another aspect of this invention refers to systems and methods for fast handovers in wireless networks such as 802.11 networks, specifically in un-managed wireless networks, and more particularly such systems and methods which allow extremely fast handovers in these networks without any changes to existing 802.11 base stations. The invention also concerns efficient performance with regards to power consumption, coverage, security, installation, capacity and availability of wireless networks such as 802.11.
The invention can achieve these goals without any change to the WiFi access point.
Currently, there is a growing number of WiFi public hot-spots (or Access Points—"AP"). These APs allow WiFi enabled devices (which we refer to as STA) that are in their coverage area to connect to the internet.
Some of the APs are operated as a business, service, or as part of a community, either with or without a charge to the STA's owner. Other APs are placed by individuals in their premises, but are not "locked", i.e., they allow bypassing STAs to utilize them. The cumulative connectivity provided by the APs is enormous and growing fast, thus, it is tempting to use this cumulative connectivity to compete with other wireless technologies. For example, it would be tempting to have a STA that looks like a cellular handset (i.e., a WiFi Handset, or WiFi Phone), where the WiFi handset uses the free connectivity to provide a "free" service that competes with or complements the cellular service.
One of the major difficulties of achieving this vision is that the coverage of a single WiFi AP is very small (about a few hundreds to a few thousands of square meters). When a user goes out of this area, his connectivity is lost. A natural naive approach to solve this problem is performing a handover (sometimes also called handoff) to another AP with a better radio connection to the user. Another approach is to have a handset which supports both WiFi and Cellular, and handover the conversation from WiFi to Cellular [See: WO 2004/0367701], this way, WiFi extends the coverage of cellular, and conversation is handed over from WiFi to cellular, when there is no WiFi coverage. However, the problem of performing handover between one WiFi AP to another WiFi AP remains when appropriate cellular coverage is not available (or there is no cooperation from the cellular company). The same idea applies when cellular is replaced by other access technology, such as satellite communications.
The concept of handover is taken from cellular networks. Handovers usually work well in managed networks, such as cellular networks, campuses, or office environment, where the entire network is usually owned by the same operator.
The network operator in many cases chooses to add cells where coverage or capacity are needed. In managed networks, the APs (or the cellular cells) are synchronized and communicate with each other through a backbone, and are usually controlled by some other network entity (e.g., BSC—base station controller in cellular systems). For example, the APs can communicate with each other, for example using the IEEE 802.11F protocol—the Inter-AP protocol, which involves a RADIUS (Remote Authentication Dial In User Service, see RFC 2138, 2865, and 2866) server.
The APs can also employ a radio resource management such as IEEE 802.11K, or fast roaming using IEEE 802.11R, etc. However, in unmanaged networks, the APs can be deployed by many unrelated entities, such as by private individuals.
There is usually no entity that synchronizes the APs. The APs can be manufactured by various manufacturers, use various security mechanisms etc. In unmanaged networks, the handovers are typically very slow, as in the process of handover, it takes time for the STA to re-connect to the internet in the new AP (and it must disconnect from the previous AP). In such a handover in an unmanaged network, the IP address often changes. Therefore, a mechanism such as mobile IP must be used (as described later). This mechanism is limited with respect to the frequency in which the IP address can change, and a large latency (disconnection time) may result during the handover process. During the latency, the STA cannot receive any incoming messages.
A handover process is typically composed of the station STA connecting to a new AP, and disconnecting from the old AP. If STA is connected in parallel to both AP the handover is called soft-handover, and if STA first abandons the old AP and then connects to the new AP, the handover is called a hard-handover. Soft handovers require the ability of STA to communicate in parallel with at least two APs.
The process of connecting to a new AP is usually composed of the following steps:
1. STA performs a scanning process to discover neighboring APs.
2. STA chooses a new AP, and performs authentication with the AP, in which the AP verifies that STA is allowed to access the AP.
3. If the authentication is successful, STA performs an association process, in which the AP acknowledges that STA is connected to it (association requires the AP to allocate resources to the STA, and the 802.11 standard allows up to 2007 STAs to be associated with an AP).
4. Once STA is associated with the AP, the STA makes sure that it has all the information that it requires to communicate over the internet, for example, it must have an IP address, and it must update servers that govern its location (such as Mobile IP, as discussed later). In some cases, the user should go through a second authentication procedure (usually with a RADIUS server). Many times, this procedure is performed over a web interface, which is called a Captive Portal.
When a captive portal is used by the AP, the user needs to surf into the captive portal and perform a log-in to connect his IP address to the Internet. In some implementations, the user's web browser is forwarded to the captive portal regardless of the internet site that it tries to surf into. Some APs allow the STA to surf in some limited number of Internet sites before they complete the second authentication procedure (for example, if the AP is in an hotel, it might allow surfing into the hotel's website, or affiliated news web sites).
The procedure at the captive portal typically includes authentication, payment or agreeing to terms of usage. Once the authentication is completed, the IP address of the STA is connected to the Internet (usually by reconfiguring the firewall that controls the communications of the AP). Each sub-process takes time to complete, resulting in a total delay of over several seconds to complete the entire process.
In managed networks, Step 4 can be performed once in a certain amount or time (or for a certain area), as moving between APs of the managed network does not necessarily change the parameters of the STA such as IP address etc. However, in un-managed networks (and sometimes also in managed networks), the STA must gain a new IP address and other parameters, usually through DHCP (Dynamic Host Configuration Protocol, see RFC 1541). Completing the DHCP protocol can take up to several seconds. Sometimes, obtaining an IP is not enough, and a second authentication is needed. In other cases, a proxy server or a Socks server should be set for the communication. The entire process can consume a few seconds, which are intolerable in a streaming two-way application such as a voice conversation.
Many protocols that are used in the Internet require that the IP address of the STA would remain fixed during communications (for example, TCP—Transport Control Protocol, see RFC 793). However, a handover might result in the change of the IP address. This change of IP address causes a break in the communication as the communication needs to be restarted.
One solution to this problem is provided by the Mobile IP standard (see RFC 2002): in this solution the STA updates a server with its current IP address, every time that the IP address changes. As a preparation for roaming, the server allocates to the STA (in addition to the STA's current IP address) an IP address that remains fixed, even when the real IP address of the STA changes. This fixed IP address is also known as a "care of" address. From this moment on, the STA keeps the server posted of the real IP address of the STA, and the STA can use (in its communications with the rest of the Internet) the "care of" address (or its home address) as if it was its own fixed address.
Any IP data packet that is sent to the care-of IP address is tunneled by the Mobile-IP server to the current IP address of the STA. For packets originating from the STA to the Internet, the STA can tunnel the packets to the Mobile-IP server, which replaces the IP address with the care-of address. However, many times the STA can simply write its care-of IP address as the source address of the IP data packet, as many times, the source address of IP packets is not checked what-so-ever in the course of routing the IP data packet in the Internet.
The Mobile-IP solution can be applied as long as the handovers are not performed too often. However, it incurs the punishment of routing all incoming packets through a server, causing both an increased travel time for the data packets, as well as latency (or disconnection) for the time that the real IP address changed, but the server is not informed yet. If the round-trip-time of the packets between the STA and the server is longer than the time a STA stays with the same IP, this method fails, as by the time packets reach the reported location of the STA, the STA is already in another location,
For many applications, such as voice, it is of utmost importance to minimize the time spent on the handover process. The time consumed by the handover process is usually dominated by the scanning step (Step 1 as mentioned above), and by Step 4 (specifically in case of an unmanaged network). There are many solutions that address fast handovers in cellular networks, and a few solutions that address fast handovers in managed WiFi networks (for example, see: WO2004/054283, which reduces Step 1 (mentioned above) by selective scanning but requires modifying the AP). None of these solutions deal with the delay due to Step 4.
It is an object of this invention to provide very fast handovers even in unmanaged networks.
Another barrier for wireless applications is that WiFi coverage might exists, and security policy might allow the STA to connect, but the AP might be out of resources (for example, there are 2007 associated STAs, and therefore it has no resources left, or that it has a limited IP address space which was already allocated through DHCP, and it has no IP address to allocate). It is an object of this invention to provide a system and method that allows STAs to use the services of the AP even when some of its resources are exhausted.
Another barrier for many wireless applications is the complex configuration of wireless parameters of STA, especially the security parameters. A user that purchases a new STA and has an existing AP, might wish to configure his new STA to work with his AP. This configuration includes entering into the STA the encryption key and authentication key that would allow it to use the AP. Existing solutions require a change in the AP and STA, such that a special key can be pressed simultaneously at both ends to perform automatic configuration (like Buffalo INC's AirStation OneTouch Secure System—AOSS, or Broadrom's SecureEasySetup). Without such a solution, the user is usually forced to punch into his STA the security codes (which are typically long). The problem worsens when the STA moves between APs that use different security settings.
It is an object of this invention to provide for easy configuration on both levels: at the initial setup and while roaming.
Another barrier for many wireless applications is that WiFi coverage might exist, but it is locked and unavailable for use for the STA. It is an object of this invention to provide a solution for (legally) accessing locked APs.
Another problem with WiFi is that the WiFi protocol is not optimized for low battery consumption (compared to cellular protocols such as GSM). In current solutions, if the STA moves between APs and changes its IP, it must use mobile IP and inform an entity (server) in the network of its current IP (we refer to this process as "location update", as the STA updates the network entity of its location). Frequent location updates exhaust the STA's battery. Another problem with frequent location updates is that they create a heavy load on the network and on the network entities that manage and keep track of the STA's location.
The situation in WiFi is very different from the situation in cellular networks in two ways. Both of the ways cause an increase in the number of location updates in WiFi. First, in cellular network, the cells are typically much larger than a "cell" that is created by a WiFi AP. Therefore, in cellular networks, there are fewer transitions between cells, and hence less location updates. Second, cellular protocols allow defining a "location area" that encompasses several cells, and the STA is required to perform location update only when moving between location areas, and thus reducing the number of location updates. Current WiFi protocols are not built to support location areas.
It is an object of this invention to provide a method that reduces the number of location updates required for STAs while moving between APs.
It is an object of the current invention to provide solutions to the above mentioned problems, using both a centralized (server based) approach, and also by providing a method for performing the solutions using a distributed peer-to-peer network. Therefore, no huge servers and no large investments are required.

Barkan Wireless Access Technologies, L.P.


The shower heated by solar energy comprises a platform (2), to a base (2a) of which is connected a piping (3) containing a water supply. A tubular body (4) is connected superiorly to the platform (2), bearing a shower head (5) at a top thereof. The platform (2) internally exhibits a plurality of conduits (7) for retaining water, which plurality of conduits (7) is exposed to solar rays.

The prior art teaches various types of showers.
The most widely found on the commercial market exhibit a head in hydraulic connection, generally via a tap valve, with a double piping for dispensing cold and hot water, the hot water coming from a boiler.
These types of showers are generally preferred for domestic environments and require installation by specialists.
The use of these showers is not preferred in open environments for obvious economic reasons.
For example, in bathing establishments or open-air swimming pools it is preferable to use showers which, once the summer season is over, can easily be removed, so that they are not subject to winter weather conditions or, even worse, to the attention of vandals.
By using portable showers, it becomes necessary to attached thereto a heating source, in place of the boiler, which heats up the water exiting from the head.
An example from the prior art includes use of a bag, located superiorly of the head and containing a quantity of water.
Externally the bag is of a dark colour so as to absorb the solar rays and consequently to heat up the water contained therein.
This type of shower has the disadvantage of having a small containing capacity for the hot water, which is linked to the size of the bag.
To obviate this drawback, Italian patent application BO2002U000067 illustrates a type of shower exhibiting a base platform from which a pipe develops vertically, which pipe terminates superiorly in the head.
The pipe is of a dark colour, and is externally enveloped by a casing, preferably trunco-cylindrical, made of a translucent material.
In this type of shower the heating of the water is obtained thanks to the sun's rays which strike the pipe and at the same time, thanks to the air jacket interpositioned between the pipe and the casing, heat loss is reduced.
This type of shower has a first disadvantage of having a small amount of surface exposed to the solar rays, which is correlated to the external diameter of the pipe.
Also, this type of shower, although provided with a greater capacity than other known types on the market, is still not up to market needs in terms of autonomy.
The conformation of this type of shower has the further drawback of being unwieldy, which is connected with the difficulty of dismounting it into its constituent parts.
In addition to this, the above-summarised portable showers do not enable cold water to be dispensed from the head in alternation with hot water.
The main aim of the present invention is to provide a sun-heated heated shower having a large surface exposed to the sun's rays and a large water reservoir.
A further aim of the present device is to provide a sun-heated shower which can provide both hot and cold water through the head.
A further aim of the present device is to provide a sun-heated hot shower which is flexible and easy to dismount, being thus small enough to store easily.
An additional aim of the present device is to provide a shower for outside use which is statically stable on the ground, even when not installed on perfectly flat terrain, or when subject to gusts of wind.
This aim and further advantages are all attained by the present invention, as it is characterised in the accompanying claims.
With reference to the figures of the drawings, 1 denotes in its entirety a solar-ray heated shower, object of the present invention.
The shower 1 exhibits a platform 2, exhibiting a base 2a and a top 2b, and a water pipe 3 connecting at the base 2a.
The platform 2 is in hydraulic communication, preferably at the top 2b thereof, with a tubular body 4 which bears at an end thereof a shower head 5.
The platform 2 exhibits, as illustrated in the figures of the drawings, a lateral perimeter and a substantially truncoconical shape, with the base 2a facing towards the ground.
At the base 2a of the platform 2 there is a pair of handles 16, 16′ for use in moving the shower 1.
The platform 2 internally exhibits a plurality of conduits 7 which collect water which is then exposed to the sun's rays.
The plurality of conduits 7 is superiorly enclosed by a preferably translucent cover 11.
The plurality of conduits 7 and the cover 11 together define means for absorbing solar energy 17.
The plurality of conduits 7 is defined by a substantially vertical first tract 8 which is destined to supply cold water and axially crosses the base 2 platform, and by a substantially spiral-developing second tract 9 destined to supply hot water which goes from the base 2a to the top 2b of the platform 2.
As shown in FIG. 2, a cold water conduit extends from adjacent the perimeter of the platform and beneath the plurality of conduits to a first location beneath the top of the platform.
The second tract 9, which is dark and preferably opaque, exhibits a plurality of circular pipes 10, 10′, 10″, 10n.
The plurality of circular pipes 10, 10′, 10″, 10n, preferably concentric, exhibit a decreasing radius in a direction going from the base 2a up to the top 2b.
Each lower circular pipe is in communication with a corresponding higher pipe via a respective lower opening 12, 12′, 12″, . . . , 12n−1 .
The plurality of openings 12, 12′, 12″, . . . , 12n−1 are in alternated arrangement either side of a separating wall 13 transversally crossing the plurality of pipes 10, 10′, 10″, 10n.
The plurality of openings, in collaboration with the separating wall 13, cause a circulation of the water, denoted in FIG. 3 by the letter V, which circulation is spiral and concentric in alternating directions.
The tubular body 4, at the lower tract communicating with the platform 2, is sub-divided into a first chamber 14 and a second chamber 14′.
The first chamber 14 is in hydraulic communication with the first tract 8.
Similarly the second chamber 14′ is in hydraulic communication with the second tract 9, preferably with the final pipe 10n located at the top 2b of the platform.
A safety valve 18 is located opposite the final pipe 10n, i.e. at the first pipe 10, preferably in the lower region thereof; the safety valve 18 is for safeguarding the tank from pressure peaks.
The tubular body 4 exhibits a mixer tap valve 6 inserted in the middle part thereof, for regulating the flow and temperature of the water issuing from the head 5.
The tap valve 6, which is of known type, enables regulation of the water jet exiting from the head 5, partially and/or alternatively by-passing the water flow crossing the first tract 8 and/or the second tract 9.
The pipe 3 supplies both the first tract 8 and the second tract 9.
The device operates as follows.
Once the shower 1 is positioned on the ground, the hydraulic connection of the pipe 3 on the first and second tracts 8, 9 of the conduits is set up.
Then, by acting on the mixer tap valve 6, in the case of a by-passing of the second tract 9 cold water is obtained from the head 5 through the first tract 8, and in the case of a by-passing of the first tract 8, the plurality of pipes 10, 10′, 10″, . . . , 10n is filled up.
After having filled up the pipes 10, 10′, 10″, . . . , 10n the tap valve 6 is closed.
When the shower 1 is left in the position it has been located in, the solar rays begin their action, heating up the water accumulated in the plurality of circular pipes 10, 10′, 10″, . . . , 10n.
By newly acting on the tap valve 6, hot water will issue from the head 5, heated internally of the second tract 9.
The tracts 9 are rather large, so as to be able to provide an adequate volume of hot water.
This also leads to a particularly good stability of the shower, without any need for applying ballast, thanks to the weight of the water which fills the conduits at the base 2.


An assembly for accessing data bits in storage locations on a succession of radially separated tracks on a rotating multilayer MSR disc comprising a storage layer and a readout layer in combination with a slider flyable over a surface of the disc with the slider supporting at least one optical element coupled to the assembly, the optical element directing light to a region of the disc including one or more storage locations, with the optical element comprising an optical fiber and a micro-machined mirror supported on the slider and adapted to direct the light to storage locations on the recording layer of the disc, a conductive coil is coupled to and supported on the assembly, a passage of current through the conductor coil is sufficient to establish a magnetic field which is coupled to the disc and in cooperation with the light stores information at one of the storage locations on the storage layer, and a magneto-resistive element is coupled to the assembly, the magneto-resistive element cooperates with the light which illuminates and heats a plurality of the storage regions of the disc along one track of the disc, the magneto-resistive element senses one of the bits from the readout layer at the storage location.

Magneto-resistive elements are well known in the art for use in magnetic disk drives. Recent advances in magnetic recording technology have provided magnetic heads using giant magneto-resistive (GMR) technology; see, for example, "Giant Magnetoresistance: A Primer," by Robert White, IEEE Transactions On Magnetics, Vol. 28, No. 5, September 1992, incorporated herein by reference. GMR heads may be manufactured to be about 5 times as sensitive to magnetic fields as conventional magneto resistive heads. GMR technology has also been incorporated with Spin-Valve structures that are well known in the art.
Magneto-optical (MO) media includes data bits written as up or down magnetic domains perpendicular to the surface of the media. In prior art MO disk drives, data is read as a clockwise or counter-clockwise rotation imposed on a reflected polarized laser light by the up or down orientations of the domains. The polarization rotation information requires an optical readout means for detection of the rotated polarized light. In the prior art, the means for readout includes a plurality of bulky and complex optical elements located on a magneto-optical head (U.S. Pat. No. 5,295,122). In the prior art, the optical elements typically degrade the signal to noise ratio (SNR) of the information conveyed by the polarization rotation before readout as an electronic signal. The prior art optical elements also contribute to the mass of the magneto-optical head and to the complexity of the alignment between the optical elements.
What is needed therefore is an apparatus that provides improved SNR readout for data stored with MO media and reduced mass and size of the associated magneto-optical head.


A form fitting nursing tank top/undershirt made with a stretch fabric includes an invisible build in nursing bra. The invisible nursing bra is partly internal and partly external. The external portion of the build in nursing bra is the left and right shoulder straps which from outside appearances form an integral part of the tank top/undershirt. The internal portion of the built in nursing bra is formed by a soft cup frame attached at the bottom to an elastic chest band and attached at the top to the front of the shoulder straps. In the back of the garment, the elastic chest band is attached to an internal back piece of fabric on the inside of the tank top. The internal back piece of fabric extends upward from the elastic chest band to the shoulder straps at the back, which shoulder straps each include an adjustable length section. Internal nursing flaps are attached at the bottom to the soft cup frame and at the top to the tank top body which forms external nursing flaps. The tank top/undershirt includes a continuous stretch body extending upward from the torso and forming the external nursing flaps which are attached to the internal nursing flaps and to the shoulder straps, to give a smooth single piece garment appearance.

A nursing bra typically includes features that permit a nursing mother to conveniently and comfortably access the breast in order to breast feed her baby.
For example, U.S. Pat. No. 6,083,079 shows a brassiere with a folding cup which is released by opening a closure at the top of the cup and folding the cup downward to access the breast. Another example is shown in U.S. Pat. No. 4,878,879 in which a specialized closure device fastens a folding cup to a nursing bra. All nursing brassieres are worn beneath an outer garment, which also must be moved aside to gain access to the folding cup of the nursing bra. U.S. Pat. No. 4,648,404 shows pair of separate but coordinated nursing undergarments, i.e., a complete bra and a complete slip that work together. An outer garment is still required. Specialized nursing clothing used as outer garments have odd-looking slits and openings and are typically available in enormous sizes.
U.S. Pat. No. 5,461,725 is typical of a specialized outer garment intended for a nursing mother. While nursing garment provides access to the mother's breast for feeding purposes, the garment fails to provide the important breast support needed by a nursing mother. As a consequence, nursing bras are often still required to be worn underneath the typical nursing outer garment.
Yet, for economy, flexibility and style, many women would prefer to wear normal everyday clothing with a nursing bra underneath. However, many common articles of clothing such as a woman's shirt or top are awkward to use with a typical nursing bra. For example, unbuttoning a blouse in public or semi-public settings is an awkward movement. Indecorous motions that attract attention often accompany accessing the nursing undergarment through regular clothing. As another example, lifting a shirt or sweater at the bottom edge of the garment to reach the nursing bra awkwardly exposes skin in the midsection or stomach area.

Stretchable nursing tank top with invisible breast support